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1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of version 2 of the GNU General Public
6 * License as published by the Free Software Foundation.
7 */
8#ifndef _UAPI__LINUX_BPF_H__
9#define _UAPI__LINUX_BPF_H__
10
11#include <linux/types.h>
12#include <linux/bpf_common.h>
13
14/* Extended instruction set based on top of classic BPF */
15
16/* instruction classes */
17#define BPF_JMP32 0x06 /* jmp mode in word width */
18#define BPF_ALU64 0x07 /* alu mode in double word width */
19
20/* ld/ldx fields */
21#define BPF_DW 0x18 /* double word (64-bit) */
22#define BPF_MEMSX 0x80 /* load with sign extension */
23#define BPF_ATOMIC 0xc0 /* atomic memory ops - op type in immediate */
24#define BPF_XADD 0xc0 /* exclusive add - legacy name */
25
26/* alu/jmp fields */
27#define BPF_MOV 0xb0 /* mov reg to reg */
28#define BPF_ARSH 0xc0 /* sign extending arithmetic shift right */
29
30/* change endianness of a register */
31#define BPF_END 0xd0 /* flags for endianness conversion: */
32#define BPF_TO_LE 0x00 /* convert to little-endian */
33#define BPF_TO_BE 0x08 /* convert to big-endian */
34#define BPF_FROM_LE BPF_TO_LE
35#define BPF_FROM_BE BPF_TO_BE
36
37/* jmp encodings */
38#define BPF_JNE 0x50 /* jump != */
39#define BPF_JLT 0xa0 /* LT is unsigned, '<' */
40#define BPF_JLE 0xb0 /* LE is unsigned, '<=' */
41#define BPF_JSGT 0x60 /* SGT is signed '>', GT in x86 */
42#define BPF_JSGE 0x70 /* SGE is signed '>=', GE in x86 */
43#define BPF_JSLT 0xc0 /* SLT is signed, '<' */
44#define BPF_JSLE 0xd0 /* SLE is signed, '<=' */
45#define BPF_JCOND 0xe0 /* conditional pseudo jumps: may_goto, goto_or_nop */
46#define BPF_CALL 0x80 /* function call */
47#define BPF_EXIT 0x90 /* function return */
48
49/* atomic op type fields (stored in immediate) */
50#define BPF_FETCH 0x01 /* not an opcode on its own, used to build others */
51#define BPF_XCHG (0xe0 | BPF_FETCH) /* atomic exchange */
52#define BPF_CMPXCHG (0xf0 | BPF_FETCH) /* atomic compare-and-write */
53
54enum bpf_cond_pseudo_jmp {
55 BPF_MAY_GOTO = 0,
56};
57
58/* Register numbers */
59enum {
60 BPF_REG_0 = 0,
61 BPF_REG_1,
62 BPF_REG_2,
63 BPF_REG_3,
64 BPF_REG_4,
65 BPF_REG_5,
66 BPF_REG_6,
67 BPF_REG_7,
68 BPF_REG_8,
69 BPF_REG_9,
70 BPF_REG_10,
71 __MAX_BPF_REG,
72};
73
74/* BPF has 10 general purpose 64-bit registers and stack frame. */
75#define MAX_BPF_REG __MAX_BPF_REG
76
77struct bpf_insn {
78 __u8 code; /* opcode */
79 __u8 dst_reg:4; /* dest register */
80 __u8 src_reg:4; /* source register */
81 __s16 off; /* signed offset */
82 __s32 imm; /* signed immediate constant */
83};
84
85/* Deprecated: use struct bpf_lpm_trie_key_u8 (when the "data" member is needed for
86 * byte access) or struct bpf_lpm_trie_key_hdr (when using an alternative type for
87 * the trailing flexible array member) instead.
88 */
89struct bpf_lpm_trie_key {
90 __u32 prefixlen; /* up to 32 for AF_INET, 128 for AF_INET6 */
91 __u8 data[0]; /* Arbitrary size */
92};
93
94/* Header for bpf_lpm_trie_key structs */
95struct bpf_lpm_trie_key_hdr {
96 __u32 prefixlen;
97};
98
99/* Key of an a BPF_MAP_TYPE_LPM_TRIE entry, with trailing byte array. */
100struct bpf_lpm_trie_key_u8 {
101 union {
102 struct bpf_lpm_trie_key_hdr hdr;
103 __u32 prefixlen;
104 };
105 __u8 data[]; /* Arbitrary size */
106};
107
108struct bpf_cgroup_storage_key {
109 __u64 cgroup_inode_id; /* cgroup inode id */
110 __u32 attach_type; /* program attach type (enum bpf_attach_type) */
111};
112
113enum bpf_cgroup_iter_order {
114 BPF_CGROUP_ITER_ORDER_UNSPEC = 0,
115 BPF_CGROUP_ITER_SELF_ONLY, /* process only a single object. */
116 BPF_CGROUP_ITER_DESCENDANTS_PRE, /* walk descendants in pre-order. */
117 BPF_CGROUP_ITER_DESCENDANTS_POST, /* walk descendants in post-order. */
118 BPF_CGROUP_ITER_ANCESTORS_UP, /* walk ancestors upward. */
119};
120
121union bpf_iter_link_info {
122 struct {
123 __u32 map_fd;
124 } map;
125 struct {
126 enum bpf_cgroup_iter_order order;
127
128 /* At most one of cgroup_fd and cgroup_id can be non-zero. If
129 * both are zero, the walk starts from the default cgroup v2
130 * root. For walking v1 hierarchy, one should always explicitly
131 * specify cgroup_fd.
132 */
133 __u32 cgroup_fd;
134 __u64 cgroup_id;
135 } cgroup;
136 /* Parameters of task iterators. */
137 struct {
138 __u32 tid;
139 __u32 pid;
140 __u32 pid_fd;
141 } task;
142};
143
144/* BPF syscall commands, see bpf(2) man-page for more details. */
145/**
146 * DOC: eBPF Syscall Preamble
147 *
148 * The operation to be performed by the **bpf**\ () system call is determined
149 * by the *cmd* argument. Each operation takes an accompanying argument,
150 * provided via *attr*, which is a pointer to a union of type *bpf_attr* (see
151 * below). The size argument is the size of the union pointed to by *attr*.
152 */
153/**
154 * DOC: eBPF Syscall Commands
155 *
156 * BPF_MAP_CREATE
157 * Description
158 * Create a map and return a file descriptor that refers to the
159 * map. The close-on-exec file descriptor flag (see **fcntl**\ (2))
160 * is automatically enabled for the new file descriptor.
161 *
162 * Applying **close**\ (2) to the file descriptor returned by
163 * **BPF_MAP_CREATE** will delete the map (but see NOTES).
164 *
165 * Return
166 * A new file descriptor (a nonnegative integer), or -1 if an
167 * error occurred (in which case, *errno* is set appropriately).
168 *
169 * BPF_MAP_LOOKUP_ELEM
170 * Description
171 * Look up an element with a given *key* in the map referred to
172 * by the file descriptor *map_fd*.
173 *
174 * The *flags* argument may be specified as one of the
175 * following:
176 *
177 * **BPF_F_LOCK**
178 * Look up the value of a spin-locked map without
179 * returning the lock. This must be specified if the
180 * elements contain a spinlock.
181 *
182 * Return
183 * Returns zero on success. On error, -1 is returned and *errno*
184 * is set appropriately.
185 *
186 * BPF_MAP_UPDATE_ELEM
187 * Description
188 * Create or update an element (key/value pair) in a specified map.
189 *
190 * The *flags* argument should be specified as one of the
191 * following:
192 *
193 * **BPF_ANY**
194 * Create a new element or update an existing element.
195 * **BPF_NOEXIST**
196 * Create a new element only if it did not exist.
197 * **BPF_EXIST**
198 * Update an existing element.
199 * **BPF_F_LOCK**
200 * Update a spin_lock-ed map element.
201 *
202 * Return
203 * Returns zero on success. On error, -1 is returned and *errno*
204 * is set appropriately.
205 *
206 * May set *errno* to **EINVAL**, **EPERM**, **ENOMEM**,
207 * **E2BIG**, **EEXIST**, or **ENOENT**.
208 *
209 * **E2BIG**
210 * The number of elements in the map reached the
211 * *max_entries* limit specified at map creation time.
212 * **EEXIST**
213 * If *flags* specifies **BPF_NOEXIST** and the element
214 * with *key* already exists in the map.
215 * **ENOENT**
216 * If *flags* specifies **BPF_EXIST** and the element with
217 * *key* does not exist in the map.
218 *
219 * BPF_MAP_DELETE_ELEM
220 * Description
221 * Look up and delete an element by key in a specified map.
222 *
223 * Return
224 * Returns zero on success. On error, -1 is returned and *errno*
225 * is set appropriately.
226 *
227 * BPF_MAP_GET_NEXT_KEY
228 * Description
229 * Look up an element by key in a specified map and return the key
230 * of the next element. Can be used to iterate over all elements
231 * in the map.
232 *
233 * Return
234 * Returns zero on success. On error, -1 is returned and *errno*
235 * is set appropriately.
236 *
237 * The following cases can be used to iterate over all elements of
238 * the map:
239 *
240 * * If *key* is not found, the operation returns zero and sets
241 * the *next_key* pointer to the key of the first element.
242 * * If *key* is found, the operation returns zero and sets the
243 * *next_key* pointer to the key of the next element.
244 * * If *key* is the last element, returns -1 and *errno* is set
245 * to **ENOENT**.
246 *
247 * May set *errno* to **ENOMEM**, **EFAULT**, **EPERM**, or
248 * **EINVAL** on error.
249 *
250 * BPF_PROG_LOAD
251 * Description
252 * Verify and load an eBPF program, returning a new file
253 * descriptor associated with the program.
254 *
255 * Applying **close**\ (2) to the file descriptor returned by
256 * **BPF_PROG_LOAD** will unload the eBPF program (but see NOTES).
257 *
258 * The close-on-exec file descriptor flag (see **fcntl**\ (2)) is
259 * automatically enabled for the new file descriptor.
260 *
261 * Return
262 * A new file descriptor (a nonnegative integer), or -1 if an
263 * error occurred (in which case, *errno* is set appropriately).
264 *
265 * BPF_OBJ_PIN
266 * Description
267 * Pin an eBPF program or map referred by the specified *bpf_fd*
268 * to the provided *pathname* on the filesystem.
269 *
270 * The *pathname* argument must not contain a dot (".").
271 *
272 * On success, *pathname* retains a reference to the eBPF object,
273 * preventing deallocation of the object when the original
274 * *bpf_fd* is closed. This allow the eBPF object to live beyond
275 * **close**\ (\ *bpf_fd*\ ), and hence the lifetime of the parent
276 * process.
277 *
278 * Applying **unlink**\ (2) or similar calls to the *pathname*
279 * unpins the object from the filesystem, removing the reference.
280 * If no other file descriptors or filesystem nodes refer to the
281 * same object, it will be deallocated (see NOTES).
282 *
283 * The filesystem type for the parent directory of *pathname* must
284 * be **BPF_FS_MAGIC**.
285 *
286 * Return
287 * Returns zero on success. On error, -1 is returned and *errno*
288 * is set appropriately.
289 *
290 * BPF_OBJ_GET
291 * Description
292 * Open a file descriptor for the eBPF object pinned to the
293 * specified *pathname*.
294 *
295 * Return
296 * A new file descriptor (a nonnegative integer), or -1 if an
297 * error occurred (in which case, *errno* is set appropriately).
298 *
299 * BPF_PROG_ATTACH
300 * Description
301 * Attach an eBPF program to a *target_fd* at the specified
302 * *attach_type* hook.
303 *
304 * The *attach_type* specifies the eBPF attachment point to
305 * attach the program to, and must be one of *bpf_attach_type*
306 * (see below).
307 *
308 * The *attach_bpf_fd* must be a valid file descriptor for a
309 * loaded eBPF program of a cgroup, flow dissector, LIRC, sockmap
310 * or sock_ops type corresponding to the specified *attach_type*.
311 *
312 * The *target_fd* must be a valid file descriptor for a kernel
313 * object which depends on the attach type of *attach_bpf_fd*:
314 *
315 * **BPF_PROG_TYPE_CGROUP_DEVICE**,
316 * **BPF_PROG_TYPE_CGROUP_SKB**,
317 * **BPF_PROG_TYPE_CGROUP_SOCK**,
318 * **BPF_PROG_TYPE_CGROUP_SOCK_ADDR**,
319 * **BPF_PROG_TYPE_CGROUP_SOCKOPT**,
320 * **BPF_PROG_TYPE_CGROUP_SYSCTL**,
321 * **BPF_PROG_TYPE_SOCK_OPS**
322 *
323 * Control Group v2 hierarchy with the eBPF controller
324 * enabled. Requires the kernel to be compiled with
325 * **CONFIG_CGROUP_BPF**.
326 *
327 * **BPF_PROG_TYPE_FLOW_DISSECTOR**
328 *
329 * Network namespace (eg /proc/self/ns/net).
330 *
331 * **BPF_PROG_TYPE_LIRC_MODE2**
332 *
333 * LIRC device path (eg /dev/lircN). Requires the kernel
334 * to be compiled with **CONFIG_BPF_LIRC_MODE2**.
335 *
336 * **BPF_PROG_TYPE_SK_SKB**,
337 * **BPF_PROG_TYPE_SK_MSG**
338 *
339 * eBPF map of socket type (eg **BPF_MAP_TYPE_SOCKHASH**).
340 *
341 * Return
342 * Returns zero on success. On error, -1 is returned and *errno*
343 * is set appropriately.
344 *
345 * BPF_PROG_DETACH
346 * Description
347 * Detach the eBPF program associated with the *target_fd* at the
348 * hook specified by *attach_type*. The program must have been
349 * previously attached using **BPF_PROG_ATTACH**.
350 *
351 * Return
352 * Returns zero on success. On error, -1 is returned and *errno*
353 * is set appropriately.
354 *
355 * BPF_PROG_TEST_RUN
356 * Description
357 * Run the eBPF program associated with the *prog_fd* a *repeat*
358 * number of times against a provided program context *ctx_in* and
359 * data *data_in*, and return the modified program context
360 * *ctx_out*, *data_out* (for example, packet data), result of the
361 * execution *retval*, and *duration* of the test run.
362 *
363 * The sizes of the buffers provided as input and output
364 * parameters *ctx_in*, *ctx_out*, *data_in*, and *data_out* must
365 * be provided in the corresponding variables *ctx_size_in*,
366 * *ctx_size_out*, *data_size_in*, and/or *data_size_out*. If any
367 * of these parameters are not provided (ie set to NULL), the
368 * corresponding size field must be zero.
369 *
370 * Some program types have particular requirements:
371 *
372 * **BPF_PROG_TYPE_SK_LOOKUP**
373 * *data_in* and *data_out* must be NULL.
374 *
375 * **BPF_PROG_TYPE_RAW_TRACEPOINT**,
376 * **BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE**
377 *
378 * *ctx_out*, *data_in* and *data_out* must be NULL.
379 * *repeat* must be zero.
380 *
381 * BPF_PROG_RUN is an alias for BPF_PROG_TEST_RUN.
382 *
383 * Return
384 * Returns zero on success. On error, -1 is returned and *errno*
385 * is set appropriately.
386 *
387 * **ENOSPC**
388 * Either *data_size_out* or *ctx_size_out* is too small.
389 * **ENOTSUPP**
390 * This command is not supported by the program type of
391 * the program referred to by *prog_fd*.
392 *
393 * BPF_PROG_GET_NEXT_ID
394 * Description
395 * Fetch the next eBPF program currently loaded into the kernel.
396 *
397 * Looks for the eBPF program with an id greater than *start_id*
398 * and updates *next_id* on success. If no other eBPF programs
399 * remain with ids higher than *start_id*, returns -1 and sets
400 * *errno* to **ENOENT**.
401 *
402 * Return
403 * Returns zero on success. On error, or when no id remains, -1
404 * is returned and *errno* is set appropriately.
405 *
406 * BPF_MAP_GET_NEXT_ID
407 * Description
408 * Fetch the next eBPF map currently loaded into the kernel.
409 *
410 * Looks for the eBPF map with an id greater than *start_id*
411 * and updates *next_id* on success. If no other eBPF maps
412 * remain with ids higher than *start_id*, returns -1 and sets
413 * *errno* to **ENOENT**.
414 *
415 * Return
416 * Returns zero on success. On error, or when no id remains, -1
417 * is returned and *errno* is set appropriately.
418 *
419 * BPF_PROG_GET_FD_BY_ID
420 * Description
421 * Open a file descriptor for the eBPF program corresponding to
422 * *prog_id*.
423 *
424 * Return
425 * A new file descriptor (a nonnegative integer), or -1 if an
426 * error occurred (in which case, *errno* is set appropriately).
427 *
428 * BPF_MAP_GET_FD_BY_ID
429 * Description
430 * Open a file descriptor for the eBPF map corresponding to
431 * *map_id*.
432 *
433 * Return
434 * A new file descriptor (a nonnegative integer), or -1 if an
435 * error occurred (in which case, *errno* is set appropriately).
436 *
437 * BPF_OBJ_GET_INFO_BY_FD
438 * Description
439 * Obtain information about the eBPF object corresponding to
440 * *bpf_fd*.
441 *
442 * Populates up to *info_len* bytes of *info*, which will be in
443 * one of the following formats depending on the eBPF object type
444 * of *bpf_fd*:
445 *
446 * * **struct bpf_prog_info**
447 * * **struct bpf_map_info**
448 * * **struct bpf_btf_info**
449 * * **struct bpf_link_info**
450 *
451 * Return
452 * Returns zero on success. On error, -1 is returned and *errno*
453 * is set appropriately.
454 *
455 * BPF_PROG_QUERY
456 * Description
457 * Obtain information about eBPF programs associated with the
458 * specified *attach_type* hook.
459 *
460 * The *target_fd* must be a valid file descriptor for a kernel
461 * object which depends on the attach type of *attach_bpf_fd*:
462 *
463 * **BPF_PROG_TYPE_CGROUP_DEVICE**,
464 * **BPF_PROG_TYPE_CGROUP_SKB**,
465 * **BPF_PROG_TYPE_CGROUP_SOCK**,
466 * **BPF_PROG_TYPE_CGROUP_SOCK_ADDR**,
467 * **BPF_PROG_TYPE_CGROUP_SOCKOPT**,
468 * **BPF_PROG_TYPE_CGROUP_SYSCTL**,
469 * **BPF_PROG_TYPE_SOCK_OPS**
470 *
471 * Control Group v2 hierarchy with the eBPF controller
472 * enabled. Requires the kernel to be compiled with
473 * **CONFIG_CGROUP_BPF**.
474 *
475 * **BPF_PROG_TYPE_FLOW_DISSECTOR**
476 *
477 * Network namespace (eg /proc/self/ns/net).
478 *
479 * **BPF_PROG_TYPE_LIRC_MODE2**
480 *
481 * LIRC device path (eg /dev/lircN). Requires the kernel
482 * to be compiled with **CONFIG_BPF_LIRC_MODE2**.
483 *
484 * **BPF_PROG_QUERY** always fetches the number of programs
485 * attached and the *attach_flags* which were used to attach those
486 * programs. Additionally, if *prog_ids* is nonzero and the number
487 * of attached programs is less than *prog_cnt*, populates
488 * *prog_ids* with the eBPF program ids of the programs attached
489 * at *target_fd*.
490 *
491 * The following flags may alter the result:
492 *
493 * **BPF_F_QUERY_EFFECTIVE**
494 * Only return information regarding programs which are
495 * currently effective at the specified *target_fd*.
496 *
497 * Return
498 * Returns zero on success. On error, -1 is returned and *errno*
499 * is set appropriately.
500 *
501 * BPF_RAW_TRACEPOINT_OPEN
502 * Description
503 * Attach an eBPF program to a tracepoint *name* to access kernel
504 * internal arguments of the tracepoint in their raw form.
505 *
506 * The *prog_fd* must be a valid file descriptor associated with
507 * a loaded eBPF program of type **BPF_PROG_TYPE_RAW_TRACEPOINT**.
508 *
509 * No ABI guarantees are made about the content of tracepoint
510 * arguments exposed to the corresponding eBPF program.
511 *
512 * Applying **close**\ (2) to the file descriptor returned by
513 * **BPF_RAW_TRACEPOINT_OPEN** will delete the map (but see NOTES).
514 *
515 * Return
516 * A new file descriptor (a nonnegative integer), or -1 if an
517 * error occurred (in which case, *errno* is set appropriately).
518 *
519 * BPF_BTF_LOAD
520 * Description
521 * Verify and load BPF Type Format (BTF) metadata into the kernel,
522 * returning a new file descriptor associated with the metadata.
523 * BTF is described in more detail at
524 * https://www.kernel.org/doc/html/latest/bpf/btf.html.
525 *
526 * The *btf* parameter must point to valid memory providing
527 * *btf_size* bytes of BTF binary metadata.
528 *
529 * The returned file descriptor can be passed to other **bpf**\ ()
530 * subcommands such as **BPF_PROG_LOAD** or **BPF_MAP_CREATE** to
531 * associate the BTF with those objects.
532 *
533 * Similar to **BPF_PROG_LOAD**, **BPF_BTF_LOAD** has optional
534 * parameters to specify a *btf_log_buf*, *btf_log_size* and
535 * *btf_log_level* which allow the kernel to return freeform log
536 * output regarding the BTF verification process.
537 *
538 * Return
539 * A new file descriptor (a nonnegative integer), or -1 if an
540 * error occurred (in which case, *errno* is set appropriately).
541 *
542 * BPF_BTF_GET_FD_BY_ID
543 * Description
544 * Open a file descriptor for the BPF Type Format (BTF)
545 * corresponding to *btf_id*.
546 *
547 * Return
548 * A new file descriptor (a nonnegative integer), or -1 if an
549 * error occurred (in which case, *errno* is set appropriately).
550 *
551 * BPF_TASK_FD_QUERY
552 * Description
553 * Obtain information about eBPF programs associated with the
554 * target process identified by *pid* and *fd*.
555 *
556 * If the *pid* and *fd* are associated with a tracepoint, kprobe
557 * or uprobe perf event, then the *prog_id* and *fd_type* will
558 * be populated with the eBPF program id and file descriptor type
559 * of type **bpf_task_fd_type**. If associated with a kprobe or
560 * uprobe, the *probe_offset* and *probe_addr* will also be
561 * populated. Optionally, if *buf* is provided, then up to
562 * *buf_len* bytes of *buf* will be populated with the name of
563 * the tracepoint, kprobe or uprobe.
564 *
565 * The resulting *prog_id* may be introspected in deeper detail
566 * using **BPF_PROG_GET_FD_BY_ID** and **BPF_OBJ_GET_INFO_BY_FD**.
567 *
568 * Return
569 * Returns zero on success. On error, -1 is returned and *errno*
570 * is set appropriately.
571 *
572 * BPF_MAP_LOOKUP_AND_DELETE_ELEM
573 * Description
574 * Look up an element with the given *key* in the map referred to
575 * by the file descriptor *fd*, and if found, delete the element.
576 *
577 * For **BPF_MAP_TYPE_QUEUE** and **BPF_MAP_TYPE_STACK** map
578 * types, the *flags* argument needs to be set to 0, but for other
579 * map types, it may be specified as:
580 *
581 * **BPF_F_LOCK**
582 * Look up and delete the value of a spin-locked map
583 * without returning the lock. This must be specified if
584 * the elements contain a spinlock.
585 *
586 * The **BPF_MAP_TYPE_QUEUE** and **BPF_MAP_TYPE_STACK** map types
587 * implement this command as a "pop" operation, deleting the top
588 * element rather than one corresponding to *key*.
589 * The *key* and *key_len* parameters should be zeroed when
590 * issuing this operation for these map types.
591 *
592 * This command is only valid for the following map types:
593 * * **BPF_MAP_TYPE_QUEUE**
594 * * **BPF_MAP_TYPE_STACK**
595 * * **BPF_MAP_TYPE_HASH**
596 * * **BPF_MAP_TYPE_PERCPU_HASH**
597 * * **BPF_MAP_TYPE_LRU_HASH**
598 * * **BPF_MAP_TYPE_LRU_PERCPU_HASH**
599 *
600 * Return
601 * Returns zero on success. On error, -1 is returned and *errno*
602 * is set appropriately.
603 *
604 * BPF_MAP_FREEZE
605 * Description
606 * Freeze the permissions of the specified map.
607 *
608 * Write permissions may be frozen by passing zero *flags*.
609 * Upon success, no future syscall invocations may alter the
610 * map state of *map_fd*. Write operations from eBPF programs
611 * are still possible for a frozen map.
612 *
613 * Not supported for maps of type **BPF_MAP_TYPE_STRUCT_OPS**.
614 *
615 * Return
616 * Returns zero on success. On error, -1 is returned and *errno*
617 * is set appropriately.
618 *
619 * BPF_BTF_GET_NEXT_ID
620 * Description
621 * Fetch the next BPF Type Format (BTF) object currently loaded
622 * into the kernel.
623 *
624 * Looks for the BTF object with an id greater than *start_id*
625 * and updates *next_id* on success. If no other BTF objects
626 * remain with ids higher than *start_id*, returns -1 and sets
627 * *errno* to **ENOENT**.
628 *
629 * Return
630 * Returns zero on success. On error, or when no id remains, -1
631 * is returned and *errno* is set appropriately.
632 *
633 * BPF_MAP_LOOKUP_BATCH
634 * Description
635 * Iterate and fetch multiple elements in a map.
636 *
637 * Two opaque values are used to manage batch operations,
638 * *in_batch* and *out_batch*. Initially, *in_batch* must be set
639 * to NULL to begin the batched operation. After each subsequent
640 * **BPF_MAP_LOOKUP_BATCH**, the caller should pass the resultant
641 * *out_batch* as the *in_batch* for the next operation to
642 * continue iteration from the current point. Both *in_batch* and
643 * *out_batch* must point to memory large enough to hold a key,
644 * except for maps of type **BPF_MAP_TYPE_{HASH, PERCPU_HASH,
645 * LRU_HASH, LRU_PERCPU_HASH}**, for which batch parameters
646 * must be at least 4 bytes wide regardless of key size.
647 *
648 * The *keys* and *values* are output parameters which must point
649 * to memory large enough to hold *count* items based on the key
650 * and value size of the map *map_fd*. The *keys* buffer must be
651 * of *key_size* * *count*. The *values* buffer must be of
652 * *value_size* * *count*.
653 *
654 * The *elem_flags* argument may be specified as one of the
655 * following:
656 *
657 * **BPF_F_LOCK**
658 * Look up the value of a spin-locked map without
659 * returning the lock. This must be specified if the
660 * elements contain a spinlock.
661 *
662 * On success, *count* elements from the map are copied into the
663 * user buffer, with the keys copied into *keys* and the values
664 * copied into the corresponding indices in *values*.
665 *
666 * If an error is returned and *errno* is not **EFAULT**, *count*
667 * is set to the number of successfully processed elements.
668 *
669 * Return
670 * Returns zero on success. On error, -1 is returned and *errno*
671 * is set appropriately.
672 *
673 * May set *errno* to **ENOSPC** to indicate that *keys* or
674 * *values* is too small to dump an entire bucket during
675 * iteration of a hash-based map type.
676 *
677 * BPF_MAP_LOOKUP_AND_DELETE_BATCH
678 * Description
679 * Iterate and delete all elements in a map.
680 *
681 * This operation has the same behavior as
682 * **BPF_MAP_LOOKUP_BATCH** with two exceptions:
683 *
684 * * Every element that is successfully returned is also deleted
685 * from the map. This is at least *count* elements. Note that
686 * *count* is both an input and an output parameter.
687 * * Upon returning with *errno* set to **EFAULT**, up to
688 * *count* elements may be deleted without returning the keys
689 * and values of the deleted elements.
690 *
691 * Return
692 * Returns zero on success. On error, -1 is returned and *errno*
693 * is set appropriately.
694 *
695 * BPF_MAP_UPDATE_BATCH
696 * Description
697 * Update multiple elements in a map by *key*.
698 *
699 * The *keys* and *values* are input parameters which must point
700 * to memory large enough to hold *count* items based on the key
701 * and value size of the map *map_fd*. The *keys* buffer must be
702 * of *key_size* * *count*. The *values* buffer must be of
703 * *value_size* * *count*.
704 *
705 * Each element specified in *keys* is sequentially updated to the
706 * value in the corresponding index in *values*. The *in_batch*
707 * and *out_batch* parameters are ignored and should be zeroed.
708 *
709 * The *elem_flags* argument should be specified as one of the
710 * following:
711 *
712 * **BPF_ANY**
713 * Create new elements or update a existing elements.
714 * **BPF_NOEXIST**
715 * Create new elements only if they do not exist.
716 * **BPF_EXIST**
717 * Update existing elements.
718 * **BPF_F_LOCK**
719 * Update spin_lock-ed map elements. This must be
720 * specified if the map value contains a spinlock.
721 *
722 * On success, *count* elements from the map are updated.
723 *
724 * If an error is returned and *errno* is not **EFAULT**, *count*
725 * is set to the number of successfully processed elements.
726 *
727 * Return
728 * Returns zero on success. On error, -1 is returned and *errno*
729 * is set appropriately.
730 *
731 * May set *errno* to **EINVAL**, **EPERM**, **ENOMEM**, or
732 * **E2BIG**. **E2BIG** indicates that the number of elements in
733 * the map reached the *max_entries* limit specified at map
734 * creation time.
735 *
736 * May set *errno* to one of the following error codes under
737 * specific circumstances:
738 *
739 * **EEXIST**
740 * If *flags* specifies **BPF_NOEXIST** and the element
741 * with *key* already exists in the map.
742 * **ENOENT**
743 * If *flags* specifies **BPF_EXIST** and the element with
744 * *key* does not exist in the map.
745 *
746 * BPF_MAP_DELETE_BATCH
747 * Description
748 * Delete multiple elements in a map by *key*.
749 *
750 * The *keys* parameter is an input parameter which must point
751 * to memory large enough to hold *count* items based on the key
752 * size of the map *map_fd*, that is, *key_size* * *count*.
753 *
754 * Each element specified in *keys* is sequentially deleted. The
755 * *in_batch*, *out_batch*, and *values* parameters are ignored
756 * and should be zeroed.
757 *
758 * The *elem_flags* argument may be specified as one of the
759 * following:
760 *
761 * **BPF_F_LOCK**
762 * Look up the value of a spin-locked map without
763 * returning the lock. This must be specified if the
764 * elements contain a spinlock.
765 *
766 * On success, *count* elements from the map are updated.
767 *
768 * If an error is returned and *errno* is not **EFAULT**, *count*
769 * is set to the number of successfully processed elements. If
770 * *errno* is **EFAULT**, up to *count* elements may be been
771 * deleted.
772 *
773 * Return
774 * Returns zero on success. On error, -1 is returned and *errno*
775 * is set appropriately.
776 *
777 * BPF_LINK_CREATE
778 * Description
779 * Attach an eBPF program to a *target_fd* at the specified
780 * *attach_type* hook and return a file descriptor handle for
781 * managing the link.
782 *
783 * Return
784 * A new file descriptor (a nonnegative integer), or -1 if an
785 * error occurred (in which case, *errno* is set appropriately).
786 *
787 * BPF_LINK_UPDATE
788 * Description
789 * Update the eBPF program in the specified *link_fd* to
790 * *new_prog_fd*.
791 *
792 * Return
793 * Returns zero on success. On error, -1 is returned and *errno*
794 * is set appropriately.
795 *
796 * BPF_LINK_GET_FD_BY_ID
797 * Description
798 * Open a file descriptor for the eBPF Link corresponding to
799 * *link_id*.
800 *
801 * Return
802 * A new file descriptor (a nonnegative integer), or -1 if an
803 * error occurred (in which case, *errno* is set appropriately).
804 *
805 * BPF_LINK_GET_NEXT_ID
806 * Description
807 * Fetch the next eBPF link currently loaded into the kernel.
808 *
809 * Looks for the eBPF link with an id greater than *start_id*
810 * and updates *next_id* on success. If no other eBPF links
811 * remain with ids higher than *start_id*, returns -1 and sets
812 * *errno* to **ENOENT**.
813 *
814 * Return
815 * Returns zero on success. On error, or when no id remains, -1
816 * is returned and *errno* is set appropriately.
817 *
818 * BPF_ENABLE_STATS
819 * Description
820 * Enable eBPF runtime statistics gathering.
821 *
822 * Runtime statistics gathering for the eBPF runtime is disabled
823 * by default to minimize the corresponding performance overhead.
824 * This command enables statistics globally.
825 *
826 * Multiple programs may independently enable statistics.
827 * After gathering the desired statistics, eBPF runtime statistics
828 * may be disabled again by calling **close**\ (2) for the file
829 * descriptor returned by this function. Statistics will only be
830 * disabled system-wide when all outstanding file descriptors
831 * returned by prior calls for this subcommand are closed.
832 *
833 * Return
834 * A new file descriptor (a nonnegative integer), or -1 if an
835 * error occurred (in which case, *errno* is set appropriately).
836 *
837 * BPF_ITER_CREATE
838 * Description
839 * Create an iterator on top of the specified *link_fd* (as
840 * previously created using **BPF_LINK_CREATE**) and return a
841 * file descriptor that can be used to trigger the iteration.
842 *
843 * If the resulting file descriptor is pinned to the filesystem
844 * using **BPF_OBJ_PIN**, then subsequent **read**\ (2) syscalls
845 * for that path will trigger the iterator to read kernel state
846 * using the eBPF program attached to *link_fd*.
847 *
848 * Return
849 * A new file descriptor (a nonnegative integer), or -1 if an
850 * error occurred (in which case, *errno* is set appropriately).
851 *
852 * BPF_LINK_DETACH
853 * Description
854 * Forcefully detach the specified *link_fd* from its
855 * corresponding attachment point.
856 *
857 * Return
858 * Returns zero on success. On error, -1 is returned and *errno*
859 * is set appropriately.
860 *
861 * BPF_PROG_BIND_MAP
862 * Description
863 * Bind a map to the lifetime of an eBPF program.
864 *
865 * The map identified by *map_fd* is bound to the program
866 * identified by *prog_fd* and only released when *prog_fd* is
867 * released. This may be used in cases where metadata should be
868 * associated with a program which otherwise does not contain any
869 * references to the map (for example, embedded in the eBPF
870 * program instructions).
871 *
872 * Return
873 * Returns zero on success. On error, -1 is returned and *errno*
874 * is set appropriately.
875 *
876 * BPF_TOKEN_CREATE
877 * Description
878 * Create BPF token with embedded information about what
879 * BPF-related functionality it allows:
880 * - a set of allowed bpf() syscall commands;
881 * - a set of allowed BPF map types to be created with
882 * BPF_MAP_CREATE command, if BPF_MAP_CREATE itself is allowed;
883 * - a set of allowed BPF program types and BPF program attach
884 * types to be loaded with BPF_PROG_LOAD command, if
885 * BPF_PROG_LOAD itself is allowed.
886 *
887 * BPF token is created (derived) from an instance of BPF FS,
888 * assuming it has necessary delegation mount options specified.
889 * This BPF token can be passed as an extra parameter to various
890 * bpf() syscall commands to grant BPF subsystem functionality to
891 * unprivileged processes.
892 *
893 * When created, BPF token is "associated" with the owning
894 * user namespace of BPF FS instance (super block) that it was
895 * derived from, and subsequent BPF operations performed with
896 * BPF token would be performing capabilities checks (i.e.,
897 * CAP_BPF, CAP_PERFMON, CAP_NET_ADMIN, CAP_SYS_ADMIN) within
898 * that user namespace. Without BPF token, such capabilities
899 * have to be granted in init user namespace, making bpf()
900 * syscall incompatible with user namespace, for the most part.
901 *
902 * Return
903 * A new file descriptor (a nonnegative integer), or -1 if an
904 * error occurred (in which case, *errno* is set appropriately).
905 *
906 * NOTES
907 * eBPF objects (maps and programs) can be shared between processes.
908 *
909 * * After **fork**\ (2), the child inherits file descriptors
910 * referring to the same eBPF objects.
911 * * File descriptors referring to eBPF objects can be transferred over
912 * **unix**\ (7) domain sockets.
913 * * File descriptors referring to eBPF objects can be duplicated in the
914 * usual way, using **dup**\ (2) and similar calls.
915 * * File descriptors referring to eBPF objects can be pinned to the
916 * filesystem using the **BPF_OBJ_PIN** command of **bpf**\ (2).
917 *
918 * An eBPF object is deallocated only after all file descriptors referring
919 * to the object have been closed and no references remain pinned to the
920 * filesystem or attached (for example, bound to a program or device).
921 */
922enum bpf_cmd {
923 BPF_MAP_CREATE,
924 BPF_MAP_LOOKUP_ELEM,
925 BPF_MAP_UPDATE_ELEM,
926 BPF_MAP_DELETE_ELEM,
927 BPF_MAP_GET_NEXT_KEY,
928 BPF_PROG_LOAD,
929 BPF_OBJ_PIN,
930 BPF_OBJ_GET,
931 BPF_PROG_ATTACH,
932 BPF_PROG_DETACH,
933 BPF_PROG_TEST_RUN,
934 BPF_PROG_RUN = BPF_PROG_TEST_RUN,
935 BPF_PROG_GET_NEXT_ID,
936 BPF_MAP_GET_NEXT_ID,
937 BPF_PROG_GET_FD_BY_ID,
938 BPF_MAP_GET_FD_BY_ID,
939 BPF_OBJ_GET_INFO_BY_FD,
940 BPF_PROG_QUERY,
941 BPF_RAW_TRACEPOINT_OPEN,
942 BPF_BTF_LOAD,
943 BPF_BTF_GET_FD_BY_ID,
944 BPF_TASK_FD_QUERY,
945 BPF_MAP_LOOKUP_AND_DELETE_ELEM,
946 BPF_MAP_FREEZE,
947 BPF_BTF_GET_NEXT_ID,
948 BPF_MAP_LOOKUP_BATCH,
949 BPF_MAP_LOOKUP_AND_DELETE_BATCH,
950 BPF_MAP_UPDATE_BATCH,
951 BPF_MAP_DELETE_BATCH,
952 BPF_LINK_CREATE,
953 BPF_LINK_UPDATE,
954 BPF_LINK_GET_FD_BY_ID,
955 BPF_LINK_GET_NEXT_ID,
956 BPF_ENABLE_STATS,
957 BPF_ITER_CREATE,
958 BPF_LINK_DETACH,
959 BPF_PROG_BIND_MAP,
960 BPF_TOKEN_CREATE,
961 __MAX_BPF_CMD,
962};
963
964enum bpf_map_type {
965 BPF_MAP_TYPE_UNSPEC,
966 BPF_MAP_TYPE_HASH,
967 BPF_MAP_TYPE_ARRAY,
968 BPF_MAP_TYPE_PROG_ARRAY,
969 BPF_MAP_TYPE_PERF_EVENT_ARRAY,
970 BPF_MAP_TYPE_PERCPU_HASH,
971 BPF_MAP_TYPE_PERCPU_ARRAY,
972 BPF_MAP_TYPE_STACK_TRACE,
973 BPF_MAP_TYPE_CGROUP_ARRAY,
974 BPF_MAP_TYPE_LRU_HASH,
975 BPF_MAP_TYPE_LRU_PERCPU_HASH,
976 BPF_MAP_TYPE_LPM_TRIE,
977 BPF_MAP_TYPE_ARRAY_OF_MAPS,
978 BPF_MAP_TYPE_HASH_OF_MAPS,
979 BPF_MAP_TYPE_DEVMAP,
980 BPF_MAP_TYPE_SOCKMAP,
981 BPF_MAP_TYPE_CPUMAP,
982 BPF_MAP_TYPE_XSKMAP,
983 BPF_MAP_TYPE_SOCKHASH,
984 BPF_MAP_TYPE_CGROUP_STORAGE_DEPRECATED,
985 /* BPF_MAP_TYPE_CGROUP_STORAGE is available to bpf programs attaching
986 * to a cgroup. The newer BPF_MAP_TYPE_CGRP_STORAGE is available to
987 * both cgroup-attached and other progs and supports all functionality
988 * provided by BPF_MAP_TYPE_CGROUP_STORAGE. So mark
989 * BPF_MAP_TYPE_CGROUP_STORAGE deprecated.
990 */
991 BPF_MAP_TYPE_CGROUP_STORAGE = BPF_MAP_TYPE_CGROUP_STORAGE_DEPRECATED,
992 BPF_MAP_TYPE_REUSEPORT_SOCKARRAY,
993 BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE_DEPRECATED,
994 /* BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE is available to bpf programs
995 * attaching to a cgroup. The new mechanism (BPF_MAP_TYPE_CGRP_STORAGE +
996 * local percpu kptr) supports all BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE
997 * functionality and more. So mark * BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE
998 * deprecated.
999 */
1000 BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE = BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE_DEPRECATED,
1001 BPF_MAP_TYPE_QUEUE,
1002 BPF_MAP_TYPE_STACK,
1003 BPF_MAP_TYPE_SK_STORAGE,
1004 BPF_MAP_TYPE_DEVMAP_HASH,
1005 BPF_MAP_TYPE_STRUCT_OPS,
1006 BPF_MAP_TYPE_RINGBUF,
1007 BPF_MAP_TYPE_INODE_STORAGE,
1008 BPF_MAP_TYPE_TASK_STORAGE,
1009 BPF_MAP_TYPE_BLOOM_FILTER,
1010 BPF_MAP_TYPE_USER_RINGBUF,
1011 BPF_MAP_TYPE_CGRP_STORAGE,
1012 BPF_MAP_TYPE_ARENA,
1013 __MAX_BPF_MAP_TYPE
1014};
1015
1016/* Note that tracing related programs such as
1017 * BPF_PROG_TYPE_{KPROBE,TRACEPOINT,PERF_EVENT,RAW_TRACEPOINT}
1018 * are not subject to a stable API since kernel internal data
1019 * structures can change from release to release and may
1020 * therefore break existing tracing BPF programs. Tracing BPF
1021 * programs correspond to /a/ specific kernel which is to be
1022 * analyzed, and not /a/ specific kernel /and/ all future ones.
1023 */
1024enum bpf_prog_type {
1025 BPF_PROG_TYPE_UNSPEC,
1026 BPF_PROG_TYPE_SOCKET_FILTER,
1027 BPF_PROG_TYPE_KPROBE,
1028 BPF_PROG_TYPE_SCHED_CLS,
1029 BPF_PROG_TYPE_SCHED_ACT,
1030 BPF_PROG_TYPE_TRACEPOINT,
1031 BPF_PROG_TYPE_XDP,
1032 BPF_PROG_TYPE_PERF_EVENT,
1033 BPF_PROG_TYPE_CGROUP_SKB,
1034 BPF_PROG_TYPE_CGROUP_SOCK,
1035 BPF_PROG_TYPE_LWT_IN,
1036 BPF_PROG_TYPE_LWT_OUT,
1037 BPF_PROG_TYPE_LWT_XMIT,
1038 BPF_PROG_TYPE_SOCK_OPS,
1039 BPF_PROG_TYPE_SK_SKB,
1040 BPF_PROG_TYPE_CGROUP_DEVICE,
1041 BPF_PROG_TYPE_SK_MSG,
1042 BPF_PROG_TYPE_RAW_TRACEPOINT,
1043 BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
1044 BPF_PROG_TYPE_LWT_SEG6LOCAL,
1045 BPF_PROG_TYPE_LIRC_MODE2,
1046 BPF_PROG_TYPE_SK_REUSEPORT,
1047 BPF_PROG_TYPE_FLOW_DISSECTOR,
1048 BPF_PROG_TYPE_CGROUP_SYSCTL,
1049 BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
1050 BPF_PROG_TYPE_CGROUP_SOCKOPT,
1051 BPF_PROG_TYPE_TRACING,
1052 BPF_PROG_TYPE_STRUCT_OPS,
1053 BPF_PROG_TYPE_EXT,
1054 BPF_PROG_TYPE_LSM,
1055 BPF_PROG_TYPE_SK_LOOKUP,
1056 BPF_PROG_TYPE_SYSCALL, /* a program that can execute syscalls */
1057 BPF_PROG_TYPE_NETFILTER,
1058 __MAX_BPF_PROG_TYPE
1059};
1060
1061enum bpf_attach_type {
1062 BPF_CGROUP_INET_INGRESS,
1063 BPF_CGROUP_INET_EGRESS,
1064 BPF_CGROUP_INET_SOCK_CREATE,
1065 BPF_CGROUP_SOCK_OPS,
1066 BPF_SK_SKB_STREAM_PARSER,
1067 BPF_SK_SKB_STREAM_VERDICT,
1068 BPF_CGROUP_DEVICE,
1069 BPF_SK_MSG_VERDICT,
1070 BPF_CGROUP_INET4_BIND,
1071 BPF_CGROUP_INET6_BIND,
1072 BPF_CGROUP_INET4_CONNECT,
1073 BPF_CGROUP_INET6_CONNECT,
1074 BPF_CGROUP_INET4_POST_BIND,
1075 BPF_CGROUP_INET6_POST_BIND,
1076 BPF_CGROUP_UDP4_SENDMSG,
1077 BPF_CGROUP_UDP6_SENDMSG,
1078 BPF_LIRC_MODE2,
1079 BPF_FLOW_DISSECTOR,
1080 BPF_CGROUP_SYSCTL,
1081 BPF_CGROUP_UDP4_RECVMSG,
1082 BPF_CGROUP_UDP6_RECVMSG,
1083 BPF_CGROUP_GETSOCKOPT,
1084 BPF_CGROUP_SETSOCKOPT,
1085 BPF_TRACE_RAW_TP,
1086 BPF_TRACE_FENTRY,
1087 BPF_TRACE_FEXIT,
1088 BPF_MODIFY_RETURN,
1089 BPF_LSM_MAC,
1090 BPF_TRACE_ITER,
1091 BPF_CGROUP_INET4_GETPEERNAME,
1092 BPF_CGROUP_INET6_GETPEERNAME,
1093 BPF_CGROUP_INET4_GETSOCKNAME,
1094 BPF_CGROUP_INET6_GETSOCKNAME,
1095 BPF_XDP_DEVMAP,
1096 BPF_CGROUP_INET_SOCK_RELEASE,
1097 BPF_XDP_CPUMAP,
1098 BPF_SK_LOOKUP,
1099 BPF_XDP,
1100 BPF_SK_SKB_VERDICT,
1101 BPF_SK_REUSEPORT_SELECT,
1102 BPF_SK_REUSEPORT_SELECT_OR_MIGRATE,
1103 BPF_PERF_EVENT,
1104 BPF_TRACE_KPROBE_MULTI,
1105 BPF_LSM_CGROUP,
1106 BPF_STRUCT_OPS,
1107 BPF_NETFILTER,
1108 BPF_TCX_INGRESS,
1109 BPF_TCX_EGRESS,
1110 BPF_TRACE_UPROBE_MULTI,
1111 BPF_CGROUP_UNIX_CONNECT,
1112 BPF_CGROUP_UNIX_SENDMSG,
1113 BPF_CGROUP_UNIX_RECVMSG,
1114 BPF_CGROUP_UNIX_GETPEERNAME,
1115 BPF_CGROUP_UNIX_GETSOCKNAME,
1116 BPF_NETKIT_PRIMARY,
1117 BPF_NETKIT_PEER,
1118 __MAX_BPF_ATTACH_TYPE
1119};
1120
1121#define MAX_BPF_ATTACH_TYPE __MAX_BPF_ATTACH_TYPE
1122
1123enum bpf_link_type {
1124 BPF_LINK_TYPE_UNSPEC = 0,
1125 BPF_LINK_TYPE_RAW_TRACEPOINT = 1,
1126 BPF_LINK_TYPE_TRACING = 2,
1127 BPF_LINK_TYPE_CGROUP = 3,
1128 BPF_LINK_TYPE_ITER = 4,
1129 BPF_LINK_TYPE_NETNS = 5,
1130 BPF_LINK_TYPE_XDP = 6,
1131 BPF_LINK_TYPE_PERF_EVENT = 7,
1132 BPF_LINK_TYPE_KPROBE_MULTI = 8,
1133 BPF_LINK_TYPE_STRUCT_OPS = 9,
1134 BPF_LINK_TYPE_NETFILTER = 10,
1135 BPF_LINK_TYPE_TCX = 11,
1136 BPF_LINK_TYPE_UPROBE_MULTI = 12,
1137 BPF_LINK_TYPE_NETKIT = 13,
1138 __MAX_BPF_LINK_TYPE,
1139};
1140
1141#define MAX_BPF_LINK_TYPE __MAX_BPF_LINK_TYPE
1142
1143enum bpf_perf_event_type {
1144 BPF_PERF_EVENT_UNSPEC = 0,
1145 BPF_PERF_EVENT_UPROBE = 1,
1146 BPF_PERF_EVENT_URETPROBE = 2,
1147 BPF_PERF_EVENT_KPROBE = 3,
1148 BPF_PERF_EVENT_KRETPROBE = 4,
1149 BPF_PERF_EVENT_TRACEPOINT = 5,
1150 BPF_PERF_EVENT_EVENT = 6,
1151};
1152
1153/* cgroup-bpf attach flags used in BPF_PROG_ATTACH command
1154 *
1155 * NONE(default): No further bpf programs allowed in the subtree.
1156 *
1157 * BPF_F_ALLOW_OVERRIDE: If a sub-cgroup installs some bpf program,
1158 * the program in this cgroup yields to sub-cgroup program.
1159 *
1160 * BPF_F_ALLOW_MULTI: If a sub-cgroup installs some bpf program,
1161 * that cgroup program gets run in addition to the program in this cgroup.
1162 *
1163 * Only one program is allowed to be attached to a cgroup with
1164 * NONE or BPF_F_ALLOW_OVERRIDE flag.
1165 * Attaching another program on top of NONE or BPF_F_ALLOW_OVERRIDE will
1166 * release old program and attach the new one. Attach flags has to match.
1167 *
1168 * Multiple programs are allowed to be attached to a cgroup with
1169 * BPF_F_ALLOW_MULTI flag. They are executed in FIFO order
1170 * (those that were attached first, run first)
1171 * The programs of sub-cgroup are executed first, then programs of
1172 * this cgroup and then programs of parent cgroup.
1173 * When children program makes decision (like picking TCP CA or sock bind)
1174 * parent program has a chance to override it.
1175 *
1176 * With BPF_F_ALLOW_MULTI a new program is added to the end of the list of
1177 * programs for a cgroup. Though it's possible to replace an old program at
1178 * any position by also specifying BPF_F_REPLACE flag and position itself in
1179 * replace_bpf_fd attribute. Old program at this position will be released.
1180 *
1181 * A cgroup with MULTI or OVERRIDE flag allows any attach flags in sub-cgroups.
1182 * A cgroup with NONE doesn't allow any programs in sub-cgroups.
1183 * Ex1:
1184 * cgrp1 (MULTI progs A, B) ->
1185 * cgrp2 (OVERRIDE prog C) ->
1186 * cgrp3 (MULTI prog D) ->
1187 * cgrp4 (OVERRIDE prog E) ->
1188 * cgrp5 (NONE prog F)
1189 * the event in cgrp5 triggers execution of F,D,A,B in that order.
1190 * if prog F is detached, the execution is E,D,A,B
1191 * if prog F and D are detached, the execution is E,A,B
1192 * if prog F, E and D are detached, the execution is C,A,B
1193 *
1194 * All eligible programs are executed regardless of return code from
1195 * earlier programs.
1196 */
1197#define BPF_F_ALLOW_OVERRIDE (1U << 0)
1198#define BPF_F_ALLOW_MULTI (1U << 1)
1199/* Generic attachment flags. */
1200#define BPF_F_REPLACE (1U << 2)
1201#define BPF_F_BEFORE (1U << 3)
1202#define BPF_F_AFTER (1U << 4)
1203#define BPF_F_ID (1U << 5)
1204#define BPF_F_LINK BPF_F_LINK /* 1 << 13 */
1205
1206/* If BPF_F_STRICT_ALIGNMENT is used in BPF_PROG_LOAD command, the
1207 * verifier will perform strict alignment checking as if the kernel
1208 * has been built with CONFIG_EFFICIENT_UNALIGNED_ACCESS not set,
1209 * and NET_IP_ALIGN defined to 2.
1210 */
1211#define BPF_F_STRICT_ALIGNMENT (1U << 0)
1212
1213/* If BPF_F_ANY_ALIGNMENT is used in BPF_PROG_LOAD command, the
1214 * verifier will allow any alignment whatsoever. On platforms
1215 * with strict alignment requirements for loads ands stores (such
1216 * as sparc and mips) the verifier validates that all loads and
1217 * stores provably follow this requirement. This flag turns that
1218 * checking and enforcement off.
1219 *
1220 * It is mostly used for testing when we want to validate the
1221 * context and memory access aspects of the verifier, but because
1222 * of an unaligned access the alignment check would trigger before
1223 * the one we are interested in.
1224 */
1225#define BPF_F_ANY_ALIGNMENT (1U << 1)
1226
1227/* BPF_F_TEST_RND_HI32 is used in BPF_PROG_LOAD command for testing purpose.
1228 * Verifier does sub-register def/use analysis and identifies instructions whose
1229 * def only matters for low 32-bit, high 32-bit is never referenced later
1230 * through implicit zero extension. Therefore verifier notifies JIT back-ends
1231 * that it is safe to ignore clearing high 32-bit for these instructions. This
1232 * saves some back-ends a lot of code-gen. However such optimization is not
1233 * necessary on some arches, for example x86_64, arm64 etc, whose JIT back-ends
1234 * hence hasn't used verifier's analysis result. But, we really want to have a
1235 * way to be able to verify the correctness of the described optimization on
1236 * x86_64 on which testsuites are frequently exercised.
1237 *
1238 * So, this flag is introduced. Once it is set, verifier will randomize high
1239 * 32-bit for those instructions who has been identified as safe to ignore them.
1240 * Then, if verifier is not doing correct analysis, such randomization will
1241 * regress tests to expose bugs.
1242 */
1243#define BPF_F_TEST_RND_HI32 (1U << 2)
1244
1245/* The verifier internal test flag. Behavior is undefined */
1246#define BPF_F_TEST_STATE_FREQ (1U << 3)
1247
1248/* If BPF_F_SLEEPABLE is used in BPF_PROG_LOAD command, the verifier will
1249 * restrict map and helper usage for such programs. Sleepable BPF programs can
1250 * only be attached to hooks where kernel execution context allows sleeping.
1251 * Such programs are allowed to use helpers that may sleep like
1252 * bpf_copy_from_user().
1253 */
1254#define BPF_F_SLEEPABLE (1U << 4)
1255
1256/* If BPF_F_XDP_HAS_FRAGS is used in BPF_PROG_LOAD command, the loaded program
1257 * fully support xdp frags.
1258 */
1259#define BPF_F_XDP_HAS_FRAGS (1U << 5)
1260
1261/* If BPF_F_XDP_DEV_BOUND_ONLY is used in BPF_PROG_LOAD command, the loaded
1262 * program becomes device-bound but can access XDP metadata.
1263 */
1264#define BPF_F_XDP_DEV_BOUND_ONLY (1U << 6)
1265
1266/* The verifier internal test flag. Behavior is undefined */
1267#define BPF_F_TEST_REG_INVARIANTS (1U << 7)
1268
1269/* link_create.kprobe_multi.flags used in LINK_CREATE command for
1270 * BPF_TRACE_KPROBE_MULTI attach type to create return probe.
1271 */
1272enum {
1273 BPF_F_KPROBE_MULTI_RETURN = (1U << 0)
1274};
1275
1276/* link_create.uprobe_multi.flags used in LINK_CREATE command for
1277 * BPF_TRACE_UPROBE_MULTI attach type to create return probe.
1278 */
1279enum {
1280 BPF_F_UPROBE_MULTI_RETURN = (1U << 0)
1281};
1282
1283/* link_create.netfilter.flags used in LINK_CREATE command for
1284 * BPF_PROG_TYPE_NETFILTER to enable IP packet defragmentation.
1285 */
1286#define BPF_F_NETFILTER_IP_DEFRAG (1U << 0)
1287
1288/* When BPF ldimm64's insn[0].src_reg != 0 then this can have
1289 * the following extensions:
1290 *
1291 * insn[0].src_reg: BPF_PSEUDO_MAP_[FD|IDX]
1292 * insn[0].imm: map fd or fd_idx
1293 * insn[1].imm: 0
1294 * insn[0].off: 0
1295 * insn[1].off: 0
1296 * ldimm64 rewrite: address of map
1297 * verifier type: CONST_PTR_TO_MAP
1298 */
1299#define BPF_PSEUDO_MAP_FD 1
1300#define BPF_PSEUDO_MAP_IDX 5
1301
1302/* insn[0].src_reg: BPF_PSEUDO_MAP_[IDX_]VALUE
1303 * insn[0].imm: map fd or fd_idx
1304 * insn[1].imm: offset into value
1305 * insn[0].off: 0
1306 * insn[1].off: 0
1307 * ldimm64 rewrite: address of map[0]+offset
1308 * verifier type: PTR_TO_MAP_VALUE
1309 */
1310#define BPF_PSEUDO_MAP_VALUE 2
1311#define BPF_PSEUDO_MAP_IDX_VALUE 6
1312
1313/* insn[0].src_reg: BPF_PSEUDO_BTF_ID
1314 * insn[0].imm: kernel btd id of VAR
1315 * insn[1].imm: 0
1316 * insn[0].off: 0
1317 * insn[1].off: 0
1318 * ldimm64 rewrite: address of the kernel variable
1319 * verifier type: PTR_TO_BTF_ID or PTR_TO_MEM, depending on whether the var
1320 * is struct/union.
1321 */
1322#define BPF_PSEUDO_BTF_ID 3
1323/* insn[0].src_reg: BPF_PSEUDO_FUNC
1324 * insn[0].imm: insn offset to the func
1325 * insn[1].imm: 0
1326 * insn[0].off: 0
1327 * insn[1].off: 0
1328 * ldimm64 rewrite: address of the function
1329 * verifier type: PTR_TO_FUNC.
1330 */
1331#define BPF_PSEUDO_FUNC 4
1332
1333/* when bpf_call->src_reg == BPF_PSEUDO_CALL, bpf_call->imm == pc-relative
1334 * offset to another bpf function
1335 */
1336#define BPF_PSEUDO_CALL 1
1337/* when bpf_call->src_reg == BPF_PSEUDO_KFUNC_CALL,
1338 * bpf_call->imm == btf_id of a BTF_KIND_FUNC in the running kernel
1339 */
1340#define BPF_PSEUDO_KFUNC_CALL 2
1341
1342enum bpf_addr_space_cast {
1343 BPF_ADDR_SPACE_CAST = 1,
1344};
1345
1346/* flags for BPF_MAP_UPDATE_ELEM command */
1347enum {
1348 BPF_ANY = 0, /* create new element or update existing */
1349 BPF_NOEXIST = 1, /* create new element if it didn't exist */
1350 BPF_EXIST = 2, /* update existing element */
1351 BPF_F_LOCK = 4, /* spin_lock-ed map_lookup/map_update */
1352};
1353
1354/* flags for BPF_MAP_CREATE command */
1355enum {
1356 BPF_F_NO_PREALLOC = (1U << 0),
1357/* Instead of having one common LRU list in the
1358 * BPF_MAP_TYPE_LRU_[PERCPU_]HASH map, use a percpu LRU list
1359 * which can scale and perform better.
1360 * Note, the LRU nodes (including free nodes) cannot be moved
1361 * across different LRU lists.
1362 */
1363 BPF_F_NO_COMMON_LRU = (1U << 1),
1364/* Specify numa node during map creation */
1365 BPF_F_NUMA_NODE = (1U << 2),
1366
1367/* Flags for accessing BPF object from syscall side. */
1368 BPF_F_RDONLY = (1U << 3),
1369 BPF_F_WRONLY = (1U << 4),
1370
1371/* Flag for stack_map, store build_id+offset instead of pointer */
1372 BPF_F_STACK_BUILD_ID = (1U << 5),
1373
1374/* Zero-initialize hash function seed. This should only be used for testing. */
1375 BPF_F_ZERO_SEED = (1U << 6),
1376
1377/* Flags for accessing BPF object from program side. */
1378 BPF_F_RDONLY_PROG = (1U << 7),
1379 BPF_F_WRONLY_PROG = (1U << 8),
1380
1381/* Clone map from listener for newly accepted socket */
1382 BPF_F_CLONE = (1U << 9),
1383
1384/* Enable memory-mapping BPF map */
1385 BPF_F_MMAPABLE = (1U << 10),
1386
1387/* Share perf_event among processes */
1388 BPF_F_PRESERVE_ELEMS = (1U << 11),
1389
1390/* Create a map that is suitable to be an inner map with dynamic max entries */
1391 BPF_F_INNER_MAP = (1U << 12),
1392
1393/* Create a map that will be registered/unregesitered by the backed bpf_link */
1394 BPF_F_LINK = (1U << 13),
1395
1396/* Get path from provided FD in BPF_OBJ_PIN/BPF_OBJ_GET commands */
1397 BPF_F_PATH_FD = (1U << 14),
1398
1399/* Flag for value_type_btf_obj_fd, the fd is available */
1400 BPF_F_VTYPE_BTF_OBJ_FD = (1U << 15),
1401
1402/* BPF token FD is passed in a corresponding command's token_fd field */
1403 BPF_F_TOKEN_FD = (1U << 16),
1404
1405/* When user space page faults in bpf_arena send SIGSEGV instead of inserting new page */
1406 BPF_F_SEGV_ON_FAULT = (1U << 17),
1407
1408/* Do not translate kernel bpf_arena pointers to user pointers */
1409 BPF_F_NO_USER_CONV = (1U << 18),
1410};
1411
1412/* Flags for BPF_PROG_QUERY. */
1413
1414/* Query effective (directly attached + inherited from ancestor cgroups)
1415 * programs that will be executed for events within a cgroup.
1416 * attach_flags with this flag are always returned 0.
1417 */
1418#define BPF_F_QUERY_EFFECTIVE (1U << 0)
1419
1420/* Flags for BPF_PROG_TEST_RUN */
1421
1422/* If set, run the test on the cpu specified by bpf_attr.test.cpu */
1423#define BPF_F_TEST_RUN_ON_CPU (1U << 0)
1424/* If set, XDP frames will be transmitted after processing */
1425#define BPF_F_TEST_XDP_LIVE_FRAMES (1U << 1)
1426
1427/* type for BPF_ENABLE_STATS */
1428enum bpf_stats_type {
1429 /* enabled run_time_ns and run_cnt */
1430 BPF_STATS_RUN_TIME = 0,
1431};
1432
1433enum bpf_stack_build_id_status {
1434 /* user space need an empty entry to identify end of a trace */
1435 BPF_STACK_BUILD_ID_EMPTY = 0,
1436 /* with valid build_id and offset */
1437 BPF_STACK_BUILD_ID_VALID = 1,
1438 /* couldn't get build_id, fallback to ip */
1439 BPF_STACK_BUILD_ID_IP = 2,
1440};
1441
1442#define BPF_BUILD_ID_SIZE 20
1443struct bpf_stack_build_id {
1444 __s32 status;
1445 unsigned char build_id[BPF_BUILD_ID_SIZE];
1446 union {
1447 __u64 offset;
1448 __u64 ip;
1449 };
1450};
1451
1452#define BPF_OBJ_NAME_LEN 16U
1453
1454union bpf_attr {
1455 struct { /* anonymous struct used by BPF_MAP_CREATE command */
1456 __u32 map_type; /* one of enum bpf_map_type */
1457 __u32 key_size; /* size of key in bytes */
1458 __u32 value_size; /* size of value in bytes */
1459 __u32 max_entries; /* max number of entries in a map */
1460 __u32 map_flags; /* BPF_MAP_CREATE related
1461 * flags defined above.
1462 */
1463 __u32 inner_map_fd; /* fd pointing to the inner map */
1464 __u32 numa_node; /* numa node (effective only if
1465 * BPF_F_NUMA_NODE is set).
1466 */
1467 char map_name[BPF_OBJ_NAME_LEN];
1468 __u32 map_ifindex; /* ifindex of netdev to create on */
1469 __u32 btf_fd; /* fd pointing to a BTF type data */
1470 __u32 btf_key_type_id; /* BTF type_id of the key */
1471 __u32 btf_value_type_id; /* BTF type_id of the value */
1472 __u32 btf_vmlinux_value_type_id;/* BTF type_id of a kernel-
1473 * struct stored as the
1474 * map value
1475 */
1476 /* Any per-map-type extra fields
1477 *
1478 * BPF_MAP_TYPE_BLOOM_FILTER - the lowest 4 bits indicate the
1479 * number of hash functions (if 0, the bloom filter will default
1480 * to using 5 hash functions).
1481 *
1482 * BPF_MAP_TYPE_ARENA - contains the address where user space
1483 * is going to mmap() the arena. It has to be page aligned.
1484 */
1485 __u64 map_extra;
1486
1487 __s32 value_type_btf_obj_fd; /* fd pointing to a BTF
1488 * type data for
1489 * btf_vmlinux_value_type_id.
1490 */
1491 /* BPF token FD to use with BPF_MAP_CREATE operation.
1492 * If provided, map_flags should have BPF_F_TOKEN_FD flag set.
1493 */
1494 __s32 map_token_fd;
1495 };
1496
1497 struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */
1498 __u32 map_fd;
1499 __aligned_u64 key;
1500 union {
1501 __aligned_u64 value;
1502 __aligned_u64 next_key;
1503 };
1504 __u64 flags;
1505 };
1506
1507 struct { /* struct used by BPF_MAP_*_BATCH commands */
1508 __aligned_u64 in_batch; /* start batch,
1509 * NULL to start from beginning
1510 */
1511 __aligned_u64 out_batch; /* output: next start batch */
1512 __aligned_u64 keys;
1513 __aligned_u64 values;
1514 __u32 count; /* input/output:
1515 * input: # of key/value
1516 * elements
1517 * output: # of filled elements
1518 */
1519 __u32 map_fd;
1520 __u64 elem_flags;
1521 __u64 flags;
1522 } batch;
1523
1524 struct { /* anonymous struct used by BPF_PROG_LOAD command */
1525 __u32 prog_type; /* one of enum bpf_prog_type */
1526 __u32 insn_cnt;
1527 __aligned_u64 insns;
1528 __aligned_u64 license;
1529 __u32 log_level; /* verbosity level of verifier */
1530 __u32 log_size; /* size of user buffer */
1531 __aligned_u64 log_buf; /* user supplied buffer */
1532 __u32 kern_version; /* not used */
1533 __u32 prog_flags;
1534 char prog_name[BPF_OBJ_NAME_LEN];
1535 __u32 prog_ifindex; /* ifindex of netdev to prep for */
1536 /* For some prog types expected attach type must be known at
1537 * load time to verify attach type specific parts of prog
1538 * (context accesses, allowed helpers, etc).
1539 */
1540 __u32 expected_attach_type;
1541 __u32 prog_btf_fd; /* fd pointing to BTF type data */
1542 __u32 func_info_rec_size; /* userspace bpf_func_info size */
1543 __aligned_u64 func_info; /* func info */
1544 __u32 func_info_cnt; /* number of bpf_func_info records */
1545 __u32 line_info_rec_size; /* userspace bpf_line_info size */
1546 __aligned_u64 line_info; /* line info */
1547 __u32 line_info_cnt; /* number of bpf_line_info records */
1548 __u32 attach_btf_id; /* in-kernel BTF type id to attach to */
1549 union {
1550 /* valid prog_fd to attach to bpf prog */
1551 __u32 attach_prog_fd;
1552 /* or valid module BTF object fd or 0 to attach to vmlinux */
1553 __u32 attach_btf_obj_fd;
1554 };
1555 __u32 core_relo_cnt; /* number of bpf_core_relo */
1556 __aligned_u64 fd_array; /* array of FDs */
1557 __aligned_u64 core_relos;
1558 __u32 core_relo_rec_size; /* sizeof(struct bpf_core_relo) */
1559 /* output: actual total log contents size (including termintaing zero).
1560 * It could be both larger than original log_size (if log was
1561 * truncated), or smaller (if log buffer wasn't filled completely).
1562 */
1563 __u32 log_true_size;
1564 /* BPF token FD to use with BPF_PROG_LOAD operation.
1565 * If provided, prog_flags should have BPF_F_TOKEN_FD flag set.
1566 */
1567 __s32 prog_token_fd;
1568 };
1569
1570 struct { /* anonymous struct used by BPF_OBJ_* commands */
1571 __aligned_u64 pathname;
1572 __u32 bpf_fd;
1573 __u32 file_flags;
1574 /* Same as dirfd in openat() syscall; see openat(2)
1575 * manpage for details of path FD and pathname semantics;
1576 * path_fd should accompanied by BPF_F_PATH_FD flag set in
1577 * file_flags field, otherwise it should be set to zero;
1578 * if BPF_F_PATH_FD flag is not set, AT_FDCWD is assumed.
1579 */
1580 __s32 path_fd;
1581 };
1582
1583 struct { /* anonymous struct used by BPF_PROG_ATTACH/DETACH commands */
1584 union {
1585 __u32 target_fd; /* target object to attach to or ... */
1586 __u32 target_ifindex; /* target ifindex */
1587 };
1588 __u32 attach_bpf_fd;
1589 __u32 attach_type;
1590 __u32 attach_flags;
1591 __u32 replace_bpf_fd;
1592 union {
1593 __u32 relative_fd;
1594 __u32 relative_id;
1595 };
1596 __u64 expected_revision;
1597 };
1598
1599 struct { /* anonymous struct used by BPF_PROG_TEST_RUN command */
1600 __u32 prog_fd;
1601 __u32 retval;
1602 __u32 data_size_in; /* input: len of data_in */
1603 __u32 data_size_out; /* input/output: len of data_out
1604 * returns ENOSPC if data_out
1605 * is too small.
1606 */
1607 __aligned_u64 data_in;
1608 __aligned_u64 data_out;
1609 __u32 repeat;
1610 __u32 duration;
1611 __u32 ctx_size_in; /* input: len of ctx_in */
1612 __u32 ctx_size_out; /* input/output: len of ctx_out
1613 * returns ENOSPC if ctx_out
1614 * is too small.
1615 */
1616 __aligned_u64 ctx_in;
1617 __aligned_u64 ctx_out;
1618 __u32 flags;
1619 __u32 cpu;
1620 __u32 batch_size;
1621 } test;
1622
1623 struct { /* anonymous struct used by BPF_*_GET_*_ID */
1624 union {
1625 __u32 start_id;
1626 __u32 prog_id;
1627 __u32 map_id;
1628 __u32 btf_id;
1629 __u32 link_id;
1630 };
1631 __u32 next_id;
1632 __u32 open_flags;
1633 };
1634
1635 struct { /* anonymous struct used by BPF_OBJ_GET_INFO_BY_FD */
1636 __u32 bpf_fd;
1637 __u32 info_len;
1638 __aligned_u64 info;
1639 } info;
1640
1641 struct { /* anonymous struct used by BPF_PROG_QUERY command */
1642 union {
1643 __u32 target_fd; /* target object to query or ... */
1644 __u32 target_ifindex; /* target ifindex */
1645 };
1646 __u32 attach_type;
1647 __u32 query_flags;
1648 __u32 attach_flags;
1649 __aligned_u64 prog_ids;
1650 union {
1651 __u32 prog_cnt;
1652 __u32 count;
1653 };
1654 __u32 :32;
1655 /* output: per-program attach_flags.
1656 * not allowed to be set during effective query.
1657 */
1658 __aligned_u64 prog_attach_flags;
1659 __aligned_u64 link_ids;
1660 __aligned_u64 link_attach_flags;
1661 __u64 revision;
1662 } query;
1663
1664 struct { /* anonymous struct used by BPF_RAW_TRACEPOINT_OPEN command */
1665 __u64 name;
1666 __u32 prog_fd;
1667 } raw_tracepoint;
1668
1669 struct { /* anonymous struct for BPF_BTF_LOAD */
1670 __aligned_u64 btf;
1671 __aligned_u64 btf_log_buf;
1672 __u32 btf_size;
1673 __u32 btf_log_size;
1674 __u32 btf_log_level;
1675 /* output: actual total log contents size (including termintaing zero).
1676 * It could be both larger than original log_size (if log was
1677 * truncated), or smaller (if log buffer wasn't filled completely).
1678 */
1679 __u32 btf_log_true_size;
1680 __u32 btf_flags;
1681 /* BPF token FD to use with BPF_BTF_LOAD operation.
1682 * If provided, btf_flags should have BPF_F_TOKEN_FD flag set.
1683 */
1684 __s32 btf_token_fd;
1685 };
1686
1687 struct {
1688 __u32 pid; /* input: pid */
1689 __u32 fd; /* input: fd */
1690 __u32 flags; /* input: flags */
1691 __u32 buf_len; /* input/output: buf len */
1692 __aligned_u64 buf; /* input/output:
1693 * tp_name for tracepoint
1694 * symbol for kprobe
1695 * filename for uprobe
1696 */
1697 __u32 prog_id; /* output: prod_id */
1698 __u32 fd_type; /* output: BPF_FD_TYPE_* */
1699 __u64 probe_offset; /* output: probe_offset */
1700 __u64 probe_addr; /* output: probe_addr */
1701 } task_fd_query;
1702
1703 struct { /* struct used by BPF_LINK_CREATE command */
1704 union {
1705 __u32 prog_fd; /* eBPF program to attach */
1706 __u32 map_fd; /* struct_ops to attach */
1707 };
1708 union {
1709 __u32 target_fd; /* target object to attach to or ... */
1710 __u32 target_ifindex; /* target ifindex */
1711 };
1712 __u32 attach_type; /* attach type */
1713 __u32 flags; /* extra flags */
1714 union {
1715 __u32 target_btf_id; /* btf_id of target to attach to */
1716 struct {
1717 __aligned_u64 iter_info; /* extra bpf_iter_link_info */
1718 __u32 iter_info_len; /* iter_info length */
1719 };
1720 struct {
1721 /* black box user-provided value passed through
1722 * to BPF program at the execution time and
1723 * accessible through bpf_get_attach_cookie() BPF helper
1724 */
1725 __u64 bpf_cookie;
1726 } perf_event;
1727 struct {
1728 __u32 flags;
1729 __u32 cnt;
1730 __aligned_u64 syms;
1731 __aligned_u64 addrs;
1732 __aligned_u64 cookies;
1733 } kprobe_multi;
1734 struct {
1735 /* this is overlaid with the target_btf_id above. */
1736 __u32 target_btf_id;
1737 /* black box user-provided value passed through
1738 * to BPF program at the execution time and
1739 * accessible through bpf_get_attach_cookie() BPF helper
1740 */
1741 __u64 cookie;
1742 } tracing;
1743 struct {
1744 __u32 pf;
1745 __u32 hooknum;
1746 __s32 priority;
1747 __u32 flags;
1748 } netfilter;
1749 struct {
1750 union {
1751 __u32 relative_fd;
1752 __u32 relative_id;
1753 };
1754 __u64 expected_revision;
1755 } tcx;
1756 struct {
1757 __aligned_u64 path;
1758 __aligned_u64 offsets;
1759 __aligned_u64 ref_ctr_offsets;
1760 __aligned_u64 cookies;
1761 __u32 cnt;
1762 __u32 flags;
1763 __u32 pid;
1764 } uprobe_multi;
1765 struct {
1766 union {
1767 __u32 relative_fd;
1768 __u32 relative_id;
1769 };
1770 __u64 expected_revision;
1771 } netkit;
1772 };
1773 } link_create;
1774
1775 struct { /* struct used by BPF_LINK_UPDATE command */
1776 __u32 link_fd; /* link fd */
1777 union {
1778 /* new program fd to update link with */
1779 __u32 new_prog_fd;
1780 /* new struct_ops map fd to update link with */
1781 __u32 new_map_fd;
1782 };
1783 __u32 flags; /* extra flags */
1784 union {
1785 /* expected link's program fd; is specified only if
1786 * BPF_F_REPLACE flag is set in flags.
1787 */
1788 __u32 old_prog_fd;
1789 /* expected link's map fd; is specified only
1790 * if BPF_F_REPLACE flag is set.
1791 */
1792 __u32 old_map_fd;
1793 };
1794 } link_update;
1795
1796 struct {
1797 __u32 link_fd;
1798 } link_detach;
1799
1800 struct { /* struct used by BPF_ENABLE_STATS command */
1801 __u32 type;
1802 } enable_stats;
1803
1804 struct { /* struct used by BPF_ITER_CREATE command */
1805 __u32 link_fd;
1806 __u32 flags;
1807 } iter_create;
1808
1809 struct { /* struct used by BPF_PROG_BIND_MAP command */
1810 __u32 prog_fd;
1811 __u32 map_fd;
1812 __u32 flags; /* extra flags */
1813 } prog_bind_map;
1814
1815 struct { /* struct used by BPF_TOKEN_CREATE command */
1816 __u32 flags;
1817 __u32 bpffs_fd;
1818 } token_create;
1819
1820} __attribute__((aligned(8)));
1821
1822/* The description below is an attempt at providing documentation to eBPF
1823 * developers about the multiple available eBPF helper functions. It can be
1824 * parsed and used to produce a manual page. The workflow is the following,
1825 * and requires the rst2man utility:
1826 *
1827 * $ ./scripts/bpf_doc.py \
1828 * --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst
1829 * $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7
1830 * $ man /tmp/bpf-helpers.7
1831 *
1832 * Note that in order to produce this external documentation, some RST
1833 * formatting is used in the descriptions to get "bold" and "italics" in
1834 * manual pages. Also note that the few trailing white spaces are
1835 * intentional, removing them would break paragraphs for rst2man.
1836 *
1837 * Start of BPF helper function descriptions:
1838 *
1839 * void *bpf_map_lookup_elem(struct bpf_map *map, const void *key)
1840 * Description
1841 * Perform a lookup in *map* for an entry associated to *key*.
1842 * Return
1843 * Map value associated to *key*, or **NULL** if no entry was
1844 * found.
1845 *
1846 * long bpf_map_update_elem(struct bpf_map *map, const void *key, const void *value, u64 flags)
1847 * Description
1848 * Add or update the value of the entry associated to *key* in
1849 * *map* with *value*. *flags* is one of:
1850 *
1851 * **BPF_NOEXIST**
1852 * The entry for *key* must not exist in the map.
1853 * **BPF_EXIST**
1854 * The entry for *key* must already exist in the map.
1855 * **BPF_ANY**
1856 * No condition on the existence of the entry for *key*.
1857 *
1858 * Flag value **BPF_NOEXIST** cannot be used for maps of types
1859 * **BPF_MAP_TYPE_ARRAY** or **BPF_MAP_TYPE_PERCPU_ARRAY** (all
1860 * elements always exist), the helper would return an error.
1861 * Return
1862 * 0 on success, or a negative error in case of failure.
1863 *
1864 * long bpf_map_delete_elem(struct bpf_map *map, const void *key)
1865 * Description
1866 * Delete entry with *key* from *map*.
1867 * Return
1868 * 0 on success, or a negative error in case of failure.
1869 *
1870 * long bpf_probe_read(void *dst, u32 size, const void *unsafe_ptr)
1871 * Description
1872 * For tracing programs, safely attempt to read *size* bytes from
1873 * kernel space address *unsafe_ptr* and store the data in *dst*.
1874 *
1875 * Generally, use **bpf_probe_read_user**\ () or
1876 * **bpf_probe_read_kernel**\ () instead.
1877 * Return
1878 * 0 on success, or a negative error in case of failure.
1879 *
1880 * u64 bpf_ktime_get_ns(void)
1881 * Description
1882 * Return the time elapsed since system boot, in nanoseconds.
1883 * Does not include time the system was suspended.
1884 * See: **clock_gettime**\ (**CLOCK_MONOTONIC**)
1885 * Return
1886 * Current *ktime*.
1887 *
1888 * long bpf_trace_printk(const char *fmt, u32 fmt_size, ...)
1889 * Description
1890 * This helper is a "printk()-like" facility for debugging. It
1891 * prints a message defined by format *fmt* (of size *fmt_size*)
1892 * to file *\/sys/kernel/tracing/trace* from TraceFS, if
1893 * available. It can take up to three additional **u64**
1894 * arguments (as an eBPF helpers, the total number of arguments is
1895 * limited to five).
1896 *
1897 * Each time the helper is called, it appends a line to the trace.
1898 * Lines are discarded while *\/sys/kernel/tracing/trace* is
1899 * open, use *\/sys/kernel/tracing/trace_pipe* to avoid this.
1900 * The format of the trace is customizable, and the exact output
1901 * one will get depends on the options set in
1902 * *\/sys/kernel/tracing/trace_options* (see also the
1903 * *README* file under the same directory). However, it usually
1904 * defaults to something like:
1905 *
1906 * ::
1907 *
1908 * telnet-470 [001] .N.. 419421.045894: 0x00000001: <formatted msg>
1909 *
1910 * In the above:
1911 *
1912 * * ``telnet`` is the name of the current task.
1913 * * ``470`` is the PID of the current task.
1914 * * ``001`` is the CPU number on which the task is
1915 * running.
1916 * * In ``.N..``, each character refers to a set of
1917 * options (whether irqs are enabled, scheduling
1918 * options, whether hard/softirqs are running, level of
1919 * preempt_disabled respectively). **N** means that
1920 * **TIF_NEED_RESCHED** and **PREEMPT_NEED_RESCHED**
1921 * are set.
1922 * * ``419421.045894`` is a timestamp.
1923 * * ``0x00000001`` is a fake value used by BPF for the
1924 * instruction pointer register.
1925 * * ``<formatted msg>`` is the message formatted with
1926 * *fmt*.
1927 *
1928 * The conversion specifiers supported by *fmt* are similar, but
1929 * more limited than for printk(). They are **%d**, **%i**,
1930 * **%u**, **%x**, **%ld**, **%li**, **%lu**, **%lx**, **%lld**,
1931 * **%lli**, **%llu**, **%llx**, **%p**, **%s**. No modifier (size
1932 * of field, padding with zeroes, etc.) is available, and the
1933 * helper will return **-EINVAL** (but print nothing) if it
1934 * encounters an unknown specifier.
1935 *
1936 * Also, note that **bpf_trace_printk**\ () is slow, and should
1937 * only be used for debugging purposes. For this reason, a notice
1938 * block (spanning several lines) is printed to kernel logs and
1939 * states that the helper should not be used "for production use"
1940 * the first time this helper is used (or more precisely, when
1941 * **trace_printk**\ () buffers are allocated). For passing values
1942 * to user space, perf events should be preferred.
1943 * Return
1944 * The number of bytes written to the buffer, or a negative error
1945 * in case of failure.
1946 *
1947 * u32 bpf_get_prandom_u32(void)
1948 * Description
1949 * Get a pseudo-random number.
1950 *
1951 * From a security point of view, this helper uses its own
1952 * pseudo-random internal state, and cannot be used to infer the
1953 * seed of other random functions in the kernel. However, it is
1954 * essential to note that the generator used by the helper is not
1955 * cryptographically secure.
1956 * Return
1957 * A random 32-bit unsigned value.
1958 *
1959 * u32 bpf_get_smp_processor_id(void)
1960 * Description
1961 * Get the SMP (symmetric multiprocessing) processor id. Note that
1962 * all programs run with migration disabled, which means that the
1963 * SMP processor id is stable during all the execution of the
1964 * program.
1965 * Return
1966 * The SMP id of the processor running the program.
1967 *
1968 * long bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len, u64 flags)
1969 * Description
1970 * Store *len* bytes from address *from* into the packet
1971 * associated to *skb*, at *offset*. *flags* are a combination of
1972 * **BPF_F_RECOMPUTE_CSUM** (automatically recompute the
1973 * checksum for the packet after storing the bytes) and
1974 * **BPF_F_INVALIDATE_HASH** (set *skb*\ **->hash**, *skb*\
1975 * **->swhash** and *skb*\ **->l4hash** to 0).
1976 *
1977 * A call to this helper is susceptible to change the underlying
1978 * packet buffer. Therefore, at load time, all checks on pointers
1979 * previously done by the verifier are invalidated and must be
1980 * performed again, if the helper is used in combination with
1981 * direct packet access.
1982 * Return
1983 * 0 on success, or a negative error in case of failure.
1984 *
1985 * long bpf_l3_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 size)
1986 * Description
1987 * Recompute the layer 3 (e.g. IP) checksum for the packet
1988 * associated to *skb*. Computation is incremental, so the helper
1989 * must know the former value of the header field that was
1990 * modified (*from*), the new value of this field (*to*), and the
1991 * number of bytes (2 or 4) for this field, stored in *size*.
1992 * Alternatively, it is possible to store the difference between
1993 * the previous and the new values of the header field in *to*, by
1994 * setting *from* and *size* to 0. For both methods, *offset*
1995 * indicates the location of the IP checksum within the packet.
1996 *
1997 * This helper works in combination with **bpf_csum_diff**\ (),
1998 * which does not update the checksum in-place, but offers more
1999 * flexibility and can handle sizes larger than 2 or 4 for the
2000 * checksum to update.
2001 *
2002 * A call to this helper is susceptible to change the underlying
2003 * packet buffer. Therefore, at load time, all checks on pointers
2004 * previously done by the verifier are invalidated and must be
2005 * performed again, if the helper is used in combination with
2006 * direct packet access.
2007 * Return
2008 * 0 on success, or a negative error in case of failure.
2009 *
2010 * long bpf_l4_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 flags)
2011 * Description
2012 * Recompute the layer 4 (e.g. TCP, UDP or ICMP) checksum for the
2013 * packet associated to *skb*. Computation is incremental, so the
2014 * helper must know the former value of the header field that was
2015 * modified (*from*), the new value of this field (*to*), and the
2016 * number of bytes (2 or 4) for this field, stored on the lowest
2017 * four bits of *flags*. Alternatively, it is possible to store
2018 * the difference between the previous and the new values of the
2019 * header field in *to*, by setting *from* and the four lowest
2020 * bits of *flags* to 0. For both methods, *offset* indicates the
2021 * location of the IP checksum within the packet. In addition to
2022 * the size of the field, *flags* can be added (bitwise OR) actual
2023 * flags. With **BPF_F_MARK_MANGLED_0**, a null checksum is left
2024 * untouched (unless **BPF_F_MARK_ENFORCE** is added as well), and
2025 * for updates resulting in a null checksum the value is set to
2026 * **CSUM_MANGLED_0** instead. Flag **BPF_F_PSEUDO_HDR** indicates
2027 * the checksum is to be computed against a pseudo-header.
2028 *
2029 * This helper works in combination with **bpf_csum_diff**\ (),
2030 * which does not update the checksum in-place, but offers more
2031 * flexibility and can handle sizes larger than 2 or 4 for the
2032 * checksum to update.
2033 *
2034 * A call to this helper is susceptible to change the underlying
2035 * packet buffer. Therefore, at load time, all checks on pointers
2036 * previously done by the verifier are invalidated and must be
2037 * performed again, if the helper is used in combination with
2038 * direct packet access.
2039 * Return
2040 * 0 on success, or a negative error in case of failure.
2041 *
2042 * long bpf_tail_call(void *ctx, struct bpf_map *prog_array_map, u32 index)
2043 * Description
2044 * This special helper is used to trigger a "tail call", or in
2045 * other words, to jump into another eBPF program. The same stack
2046 * frame is used (but values on stack and in registers for the
2047 * caller are not accessible to the callee). This mechanism allows
2048 * for program chaining, either for raising the maximum number of
2049 * available eBPF instructions, or to execute given programs in
2050 * conditional blocks. For security reasons, there is an upper
2051 * limit to the number of successive tail calls that can be
2052 * performed.
2053 *
2054 * Upon call of this helper, the program attempts to jump into a
2055 * program referenced at index *index* in *prog_array_map*, a
2056 * special map of type **BPF_MAP_TYPE_PROG_ARRAY**, and passes
2057 * *ctx*, a pointer to the context.
2058 *
2059 * If the call succeeds, the kernel immediately runs the first
2060 * instruction of the new program. This is not a function call,
2061 * and it never returns to the previous program. If the call
2062 * fails, then the helper has no effect, and the caller continues
2063 * to run its subsequent instructions. A call can fail if the
2064 * destination program for the jump does not exist (i.e. *index*
2065 * is superior to the number of entries in *prog_array_map*), or
2066 * if the maximum number of tail calls has been reached for this
2067 * chain of programs. This limit is defined in the kernel by the
2068 * macro **MAX_TAIL_CALL_CNT** (not accessible to user space),
2069 * which is currently set to 33.
2070 * Return
2071 * 0 on success, or a negative error in case of failure.
2072 *
2073 * long bpf_clone_redirect(struct sk_buff *skb, u32 ifindex, u64 flags)
2074 * Description
2075 * Clone and redirect the packet associated to *skb* to another
2076 * net device of index *ifindex*. Both ingress and egress
2077 * interfaces can be used for redirection. The **BPF_F_INGRESS**
2078 * value in *flags* is used to make the distinction (ingress path
2079 * is selected if the flag is present, egress path otherwise).
2080 * This is the only flag supported for now.
2081 *
2082 * In comparison with **bpf_redirect**\ () helper,
2083 * **bpf_clone_redirect**\ () has the associated cost of
2084 * duplicating the packet buffer, but this can be executed out of
2085 * the eBPF program. Conversely, **bpf_redirect**\ () is more
2086 * efficient, but it is handled through an action code where the
2087 * redirection happens only after the eBPF program has returned.
2088 *
2089 * A call to this helper is susceptible to change the underlying
2090 * packet buffer. Therefore, at load time, all checks on pointers
2091 * previously done by the verifier are invalidated and must be
2092 * performed again, if the helper is used in combination with
2093 * direct packet access.
2094 * Return
2095 * 0 on success, or a negative error in case of failure. Positive
2096 * error indicates a potential drop or congestion in the target
2097 * device. The particular positive error codes are not defined.
2098 *
2099 * u64 bpf_get_current_pid_tgid(void)
2100 * Description
2101 * Get the current pid and tgid.
2102 * Return
2103 * A 64-bit integer containing the current tgid and pid, and
2104 * created as such:
2105 * *current_task*\ **->tgid << 32 \|**
2106 * *current_task*\ **->pid**.
2107 *
2108 * u64 bpf_get_current_uid_gid(void)
2109 * Description
2110 * Get the current uid and gid.
2111 * Return
2112 * A 64-bit integer containing the current GID and UID, and
2113 * created as such: *current_gid* **<< 32 \|** *current_uid*.
2114 *
2115 * long bpf_get_current_comm(void *buf, u32 size_of_buf)
2116 * Description
2117 * Copy the **comm** attribute of the current task into *buf* of
2118 * *size_of_buf*. The **comm** attribute contains the name of
2119 * the executable (excluding the path) for the current task. The
2120 * *size_of_buf* must be strictly positive. On success, the
2121 * helper makes sure that the *buf* is NUL-terminated. On failure,
2122 * it is filled with zeroes.
2123 * Return
2124 * 0 on success, or a negative error in case of failure.
2125 *
2126 * u32 bpf_get_cgroup_classid(struct sk_buff *skb)
2127 * Description
2128 * Retrieve the classid for the current task, i.e. for the net_cls
2129 * cgroup to which *skb* belongs.
2130 *
2131 * This helper can be used on TC egress path, but not on ingress.
2132 *
2133 * The net_cls cgroup provides an interface to tag network packets
2134 * based on a user-provided identifier for all traffic coming from
2135 * the tasks belonging to the related cgroup. See also the related
2136 * kernel documentation, available from the Linux sources in file
2137 * *Documentation/admin-guide/cgroup-v1/net_cls.rst*.
2138 *
2139 * The Linux kernel has two versions for cgroups: there are
2140 * cgroups v1 and cgroups v2. Both are available to users, who can
2141 * use a mixture of them, but note that the net_cls cgroup is for
2142 * cgroup v1 only. This makes it incompatible with BPF programs
2143 * run on cgroups, which is a cgroup-v2-only feature (a socket can
2144 * only hold data for one version of cgroups at a time).
2145 *
2146 * This helper is only available is the kernel was compiled with
2147 * the **CONFIG_CGROUP_NET_CLASSID** configuration option set to
2148 * "**y**" or to "**m**".
2149 * Return
2150 * The classid, or 0 for the default unconfigured classid.
2151 *
2152 * long bpf_skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci)
2153 * Description
2154 * Push a *vlan_tci* (VLAN tag control information) of protocol
2155 * *vlan_proto* to the packet associated to *skb*, then update
2156 * the checksum. Note that if *vlan_proto* is different from
2157 * **ETH_P_8021Q** and **ETH_P_8021AD**, it is considered to
2158 * be **ETH_P_8021Q**.
2159 *
2160 * A call to this helper is susceptible to change the underlying
2161 * packet buffer. Therefore, at load time, all checks on pointers
2162 * previously done by the verifier are invalidated and must be
2163 * performed again, if the helper is used in combination with
2164 * direct packet access.
2165 * Return
2166 * 0 on success, or a negative error in case of failure.
2167 *
2168 * long bpf_skb_vlan_pop(struct sk_buff *skb)
2169 * Description
2170 * Pop a VLAN header from the packet associated to *skb*.
2171 *
2172 * A call to this helper is susceptible to change the underlying
2173 * packet buffer. Therefore, at load time, all checks on pointers
2174 * previously done by the verifier are invalidated and must be
2175 * performed again, if the helper is used in combination with
2176 * direct packet access.
2177 * Return
2178 * 0 on success, or a negative error in case of failure.
2179 *
2180 * long bpf_skb_get_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags)
2181 * Description
2182 * Get tunnel metadata. This helper takes a pointer *key* to an
2183 * empty **struct bpf_tunnel_key** of **size**, that will be
2184 * filled with tunnel metadata for the packet associated to *skb*.
2185 * The *flags* can be set to **BPF_F_TUNINFO_IPV6**, which
2186 * indicates that the tunnel is based on IPv6 protocol instead of
2187 * IPv4.
2188 *
2189 * The **struct bpf_tunnel_key** is an object that generalizes the
2190 * principal parameters used by various tunneling protocols into a
2191 * single struct. This way, it can be used to easily make a
2192 * decision based on the contents of the encapsulation header,
2193 * "summarized" in this struct. In particular, it holds the IP
2194 * address of the remote end (IPv4 or IPv6, depending on the case)
2195 * in *key*\ **->remote_ipv4** or *key*\ **->remote_ipv6**. Also,
2196 * this struct exposes the *key*\ **->tunnel_id**, which is
2197 * generally mapped to a VNI (Virtual Network Identifier), making
2198 * it programmable together with the **bpf_skb_set_tunnel_key**\
2199 * () helper.
2200 *
2201 * Let's imagine that the following code is part of a program
2202 * attached to the TC ingress interface, on one end of a GRE
2203 * tunnel, and is supposed to filter out all messages coming from
2204 * remote ends with IPv4 address other than 10.0.0.1:
2205 *
2206 * ::
2207 *
2208 * int ret;
2209 * struct bpf_tunnel_key key = {};
2210 *
2211 * ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
2212 * if (ret < 0)
2213 * return TC_ACT_SHOT; // drop packet
2214 *
2215 * if (key.remote_ipv4 != 0x0a000001)
2216 * return TC_ACT_SHOT; // drop packet
2217 *
2218 * return TC_ACT_OK; // accept packet
2219 *
2220 * This interface can also be used with all encapsulation devices
2221 * that can operate in "collect metadata" mode: instead of having
2222 * one network device per specific configuration, the "collect
2223 * metadata" mode only requires a single device where the
2224 * configuration can be extracted from this helper.
2225 *
2226 * This can be used together with various tunnels such as VXLan,
2227 * Geneve, GRE or IP in IP (IPIP).
2228 * Return
2229 * 0 on success, or a negative error in case of failure.
2230 *
2231 * long bpf_skb_set_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags)
2232 * Description
2233 * Populate tunnel metadata for packet associated to *skb.* The
2234 * tunnel metadata is set to the contents of *key*, of *size*. The
2235 * *flags* can be set to a combination of the following values:
2236 *
2237 * **BPF_F_TUNINFO_IPV6**
2238 * Indicate that the tunnel is based on IPv6 protocol
2239 * instead of IPv4.
2240 * **BPF_F_ZERO_CSUM_TX**
2241 * For IPv4 packets, add a flag to tunnel metadata
2242 * indicating that checksum computation should be skipped
2243 * and checksum set to zeroes.
2244 * **BPF_F_DONT_FRAGMENT**
2245 * Add a flag to tunnel metadata indicating that the
2246 * packet should not be fragmented.
2247 * **BPF_F_SEQ_NUMBER**
2248 * Add a flag to tunnel metadata indicating that a
2249 * sequence number should be added to tunnel header before
2250 * sending the packet. This flag was added for GRE
2251 * encapsulation, but might be used with other protocols
2252 * as well in the future.
2253 * **BPF_F_NO_TUNNEL_KEY**
2254 * Add a flag to tunnel metadata indicating that no tunnel
2255 * key should be set in the resulting tunnel header.
2256 *
2257 * Here is a typical usage on the transmit path:
2258 *
2259 * ::
2260 *
2261 * struct bpf_tunnel_key key;
2262 * populate key ...
2263 * bpf_skb_set_tunnel_key(skb, &key, sizeof(key), 0);
2264 * bpf_clone_redirect(skb, vxlan_dev_ifindex, 0);
2265 *
2266 * See also the description of the **bpf_skb_get_tunnel_key**\ ()
2267 * helper for additional information.
2268 * Return
2269 * 0 on success, or a negative error in case of failure.
2270 *
2271 * u64 bpf_perf_event_read(struct bpf_map *map, u64 flags)
2272 * Description
2273 * Read the value of a perf event counter. This helper relies on a
2274 * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of
2275 * the perf event counter is selected when *map* is updated with
2276 * perf event file descriptors. The *map* is an array whose size
2277 * is the number of available CPUs, and each cell contains a value
2278 * relative to one CPU. The value to retrieve is indicated by
2279 * *flags*, that contains the index of the CPU to look up, masked
2280 * with **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to
2281 * **BPF_F_CURRENT_CPU** to indicate that the value for the
2282 * current CPU should be retrieved.
2283 *
2284 * Note that before Linux 4.13, only hardware perf event can be
2285 * retrieved.
2286 *
2287 * Also, be aware that the newer helper
2288 * **bpf_perf_event_read_value**\ () is recommended over
2289 * **bpf_perf_event_read**\ () in general. The latter has some ABI
2290 * quirks where error and counter value are used as a return code
2291 * (which is wrong to do since ranges may overlap). This issue is
2292 * fixed with **bpf_perf_event_read_value**\ (), which at the same
2293 * time provides more features over the **bpf_perf_event_read**\
2294 * () interface. Please refer to the description of
2295 * **bpf_perf_event_read_value**\ () for details.
2296 * Return
2297 * The value of the perf event counter read from the map, or a
2298 * negative error code in case of failure.
2299 *
2300 * long bpf_redirect(u32 ifindex, u64 flags)
2301 * Description
2302 * Redirect the packet to another net device of index *ifindex*.
2303 * This helper is somewhat similar to **bpf_clone_redirect**\
2304 * (), except that the packet is not cloned, which provides
2305 * increased performance.
2306 *
2307 * Except for XDP, both ingress and egress interfaces can be used
2308 * for redirection. The **BPF_F_INGRESS** value in *flags* is used
2309 * to make the distinction (ingress path is selected if the flag
2310 * is present, egress path otherwise). Currently, XDP only
2311 * supports redirection to the egress interface, and accepts no
2312 * flag at all.
2313 *
2314 * The same effect can also be attained with the more generic
2315 * **bpf_redirect_map**\ (), which uses a BPF map to store the
2316 * redirect target instead of providing it directly to the helper.
2317 * Return
2318 * For XDP, the helper returns **XDP_REDIRECT** on success or
2319 * **XDP_ABORTED** on error. For other program types, the values
2320 * are **TC_ACT_REDIRECT** on success or **TC_ACT_SHOT** on
2321 * error.
2322 *
2323 * u32 bpf_get_route_realm(struct sk_buff *skb)
2324 * Description
2325 * Retrieve the realm or the route, that is to say the
2326 * **tclassid** field of the destination for the *skb*. The
2327 * identifier retrieved is a user-provided tag, similar to the
2328 * one used with the net_cls cgroup (see description for
2329 * **bpf_get_cgroup_classid**\ () helper), but here this tag is
2330 * held by a route (a destination entry), not by a task.
2331 *
2332 * Retrieving this identifier works with the clsact TC egress hook
2333 * (see also **tc-bpf(8)**), or alternatively on conventional
2334 * classful egress qdiscs, but not on TC ingress path. In case of
2335 * clsact TC egress hook, this has the advantage that, internally,
2336 * the destination entry has not been dropped yet in the transmit
2337 * path. Therefore, the destination entry does not need to be
2338 * artificially held via **netif_keep_dst**\ () for a classful
2339 * qdisc until the *skb* is freed.
2340 *
2341 * This helper is available only if the kernel was compiled with
2342 * **CONFIG_IP_ROUTE_CLASSID** configuration option.
2343 * Return
2344 * The realm of the route for the packet associated to *skb*, or 0
2345 * if none was found.
2346 *
2347 * long bpf_perf_event_output(void *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
2348 * Description
2349 * Write raw *data* blob into a special BPF perf event held by
2350 * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf
2351 * event must have the following attributes: **PERF_SAMPLE_RAW**
2352 * as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and
2353 * **PERF_COUNT_SW_BPF_OUTPUT** as **config**.
2354 *
2355 * The *flags* are used to indicate the index in *map* for which
2356 * the value must be put, masked with **BPF_F_INDEX_MASK**.
2357 * Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU**
2358 * to indicate that the index of the current CPU core should be
2359 * used.
2360 *
2361 * The value to write, of *size*, is passed through eBPF stack and
2362 * pointed by *data*.
2363 *
2364 * The context of the program *ctx* needs also be passed to the
2365 * helper.
2366 *
2367 * On user space, a program willing to read the values needs to
2368 * call **perf_event_open**\ () on the perf event (either for
2369 * one or for all CPUs) and to store the file descriptor into the
2370 * *map*. This must be done before the eBPF program can send data
2371 * into it. An example is available in file
2372 * *samples/bpf/trace_output_user.c* in the Linux kernel source
2373 * tree (the eBPF program counterpart is in
2374 * *samples/bpf/trace_output_kern.c*).
2375 *
2376 * **bpf_perf_event_output**\ () achieves better performance
2377 * than **bpf_trace_printk**\ () for sharing data with user
2378 * space, and is much better suitable for streaming data from eBPF
2379 * programs.
2380 *
2381 * Note that this helper is not restricted to tracing use cases
2382 * and can be used with programs attached to TC or XDP as well,
2383 * where it allows for passing data to user space listeners. Data
2384 * can be:
2385 *
2386 * * Only custom structs,
2387 * * Only the packet payload, or
2388 * * A combination of both.
2389 * Return
2390 * 0 on success, or a negative error in case of failure.
2391 *
2392 * long bpf_skb_load_bytes(const void *skb, u32 offset, void *to, u32 len)
2393 * Description
2394 * This helper was provided as an easy way to load data from a
2395 * packet. It can be used to load *len* bytes from *offset* from
2396 * the packet associated to *skb*, into the buffer pointed by
2397 * *to*.
2398 *
2399 * Since Linux 4.7, usage of this helper has mostly been replaced
2400 * by "direct packet access", enabling packet data to be
2401 * manipulated with *skb*\ **->data** and *skb*\ **->data_end**
2402 * pointing respectively to the first byte of packet data and to
2403 * the byte after the last byte of packet data. However, it
2404 * remains useful if one wishes to read large quantities of data
2405 * at once from a packet into the eBPF stack.
2406 * Return
2407 * 0 on success, or a negative error in case of failure.
2408 *
2409 * long bpf_get_stackid(void *ctx, struct bpf_map *map, u64 flags)
2410 * Description
2411 * Walk a user or a kernel stack and return its id. To achieve
2412 * this, the helper needs *ctx*, which is a pointer to the context
2413 * on which the tracing program is executed, and a pointer to a
2414 * *map* of type **BPF_MAP_TYPE_STACK_TRACE**.
2415 *
2416 * The last argument, *flags*, holds the number of stack frames to
2417 * skip (from 0 to 255), masked with
2418 * **BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set
2419 * a combination of the following flags:
2420 *
2421 * **BPF_F_USER_STACK**
2422 * Collect a user space stack instead of a kernel stack.
2423 * **BPF_F_FAST_STACK_CMP**
2424 * Compare stacks by hash only.
2425 * **BPF_F_REUSE_STACKID**
2426 * If two different stacks hash into the same *stackid*,
2427 * discard the old one.
2428 *
2429 * The stack id retrieved is a 32 bit long integer handle which
2430 * can be further combined with other data (including other stack
2431 * ids) and used as a key into maps. This can be useful for
2432 * generating a variety of graphs (such as flame graphs or off-cpu
2433 * graphs).
2434 *
2435 * For walking a stack, this helper is an improvement over
2436 * **bpf_probe_read**\ (), which can be used with unrolled loops
2437 * but is not efficient and consumes a lot of eBPF instructions.
2438 * Instead, **bpf_get_stackid**\ () can collect up to
2439 * **PERF_MAX_STACK_DEPTH** both kernel and user frames. Note that
2440 * this limit can be controlled with the **sysctl** program, and
2441 * that it should be manually increased in order to profile long
2442 * user stacks (such as stacks for Java programs). To do so, use:
2443 *
2444 * ::
2445 *
2446 * # sysctl kernel.perf_event_max_stack=<new value>
2447 * Return
2448 * The positive or null stack id on success, or a negative error
2449 * in case of failure.
2450 *
2451 * s64 bpf_csum_diff(__be32 *from, u32 from_size, __be32 *to, u32 to_size, __wsum seed)
2452 * Description
2453 * Compute a checksum difference, from the raw buffer pointed by
2454 * *from*, of length *from_size* (that must be a multiple of 4),
2455 * towards the raw buffer pointed by *to*, of size *to_size*
2456 * (same remark). An optional *seed* can be added to the value
2457 * (this can be cascaded, the seed may come from a previous call
2458 * to the helper).
2459 *
2460 * This is flexible enough to be used in several ways:
2461 *
2462 * * With *from_size* == 0, *to_size* > 0 and *seed* set to
2463 * checksum, it can be used when pushing new data.
2464 * * With *from_size* > 0, *to_size* == 0 and *seed* set to
2465 * checksum, it can be used when removing data from a packet.
2466 * * With *from_size* > 0, *to_size* > 0 and *seed* set to 0, it
2467 * can be used to compute a diff. Note that *from_size* and
2468 * *to_size* do not need to be equal.
2469 *
2470 * This helper can be used in combination with
2471 * **bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\ (), to
2472 * which one can feed in the difference computed with
2473 * **bpf_csum_diff**\ ().
2474 * Return
2475 * The checksum result, or a negative error code in case of
2476 * failure.
2477 *
2478 * long bpf_skb_get_tunnel_opt(struct sk_buff *skb, void *opt, u32 size)
2479 * Description
2480 * Retrieve tunnel options metadata for the packet associated to
2481 * *skb*, and store the raw tunnel option data to the buffer *opt*
2482 * of *size*.
2483 *
2484 * This helper can be used with encapsulation devices that can
2485 * operate in "collect metadata" mode (please refer to the related
2486 * note in the description of **bpf_skb_get_tunnel_key**\ () for
2487 * more details). A particular example where this can be used is
2488 * in combination with the Geneve encapsulation protocol, where it
2489 * allows for pushing (with **bpf_skb_get_tunnel_opt**\ () helper)
2490 * and retrieving arbitrary TLVs (Type-Length-Value headers) from
2491 * the eBPF program. This allows for full customization of these
2492 * headers.
2493 * Return
2494 * The size of the option data retrieved.
2495 *
2496 * long bpf_skb_set_tunnel_opt(struct sk_buff *skb, void *opt, u32 size)
2497 * Description
2498 * Set tunnel options metadata for the packet associated to *skb*
2499 * to the option data contained in the raw buffer *opt* of *size*.
2500 *
2501 * See also the description of the **bpf_skb_get_tunnel_opt**\ ()
2502 * helper for additional information.
2503 * Return
2504 * 0 on success, or a negative error in case of failure.
2505 *
2506 * long bpf_skb_change_proto(struct sk_buff *skb, __be16 proto, u64 flags)
2507 * Description
2508 * Change the protocol of the *skb* to *proto*. Currently
2509 * supported are transition from IPv4 to IPv6, and from IPv6 to
2510 * IPv4. The helper takes care of the groundwork for the
2511 * transition, including resizing the socket buffer. The eBPF
2512 * program is expected to fill the new headers, if any, via
2513 * **skb_store_bytes**\ () and to recompute the checksums with
2514 * **bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\
2515 * (). The main case for this helper is to perform NAT64
2516 * operations out of an eBPF program.
2517 *
2518 * Internally, the GSO type is marked as dodgy so that headers are
2519 * checked and segments are recalculated by the GSO/GRO engine.
2520 * The size for GSO target is adapted as well.
2521 *
2522 * All values for *flags* are reserved for future usage, and must
2523 * be left at zero.
2524 *
2525 * A call to this helper is susceptible to change the underlying
2526 * packet buffer. Therefore, at load time, all checks on pointers
2527 * previously done by the verifier are invalidated and must be
2528 * performed again, if the helper is used in combination with
2529 * direct packet access.
2530 * Return
2531 * 0 on success, or a negative error in case of failure.
2532 *
2533 * long bpf_skb_change_type(struct sk_buff *skb, u32 type)
2534 * Description
2535 * Change the packet type for the packet associated to *skb*. This
2536 * comes down to setting *skb*\ **->pkt_type** to *type*, except
2537 * the eBPF program does not have a write access to *skb*\
2538 * **->pkt_type** beside this helper. Using a helper here allows
2539 * for graceful handling of errors.
2540 *
2541 * The major use case is to change incoming *skb*s to
2542 * **PACKET_HOST** in a programmatic way instead of having to
2543 * recirculate via **redirect**\ (..., **BPF_F_INGRESS**), for
2544 * example.
2545 *
2546 * Note that *type* only allows certain values. At this time, they
2547 * are:
2548 *
2549 * **PACKET_HOST**
2550 * Packet is for us.
2551 * **PACKET_BROADCAST**
2552 * Send packet to all.
2553 * **PACKET_MULTICAST**
2554 * Send packet to group.
2555 * **PACKET_OTHERHOST**
2556 * Send packet to someone else.
2557 * Return
2558 * 0 on success, or a negative error in case of failure.
2559 *
2560 * long bpf_skb_under_cgroup(struct sk_buff *skb, struct bpf_map *map, u32 index)
2561 * Description
2562 * Check whether *skb* is a descendant of the cgroup2 held by
2563 * *map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*.
2564 * Return
2565 * The return value depends on the result of the test, and can be:
2566 *
2567 * * 0, if the *skb* failed the cgroup2 descendant test.
2568 * * 1, if the *skb* succeeded the cgroup2 descendant test.
2569 * * A negative error code, if an error occurred.
2570 *
2571 * u32 bpf_get_hash_recalc(struct sk_buff *skb)
2572 * Description
2573 * Retrieve the hash of the packet, *skb*\ **->hash**. If it is
2574 * not set, in particular if the hash was cleared due to mangling,
2575 * recompute this hash. Later accesses to the hash can be done
2576 * directly with *skb*\ **->hash**.
2577 *
2578 * Calling **bpf_set_hash_invalid**\ (), changing a packet
2579 * prototype with **bpf_skb_change_proto**\ (), or calling
2580 * **bpf_skb_store_bytes**\ () with the
2581 * **BPF_F_INVALIDATE_HASH** are actions susceptible to clear
2582 * the hash and to trigger a new computation for the next call to
2583 * **bpf_get_hash_recalc**\ ().
2584 * Return
2585 * The 32-bit hash.
2586 *
2587 * u64 bpf_get_current_task(void)
2588 * Description
2589 * Get the current task.
2590 * Return
2591 * A pointer to the current task struct.
2592 *
2593 * long bpf_probe_write_user(void *dst, const void *src, u32 len)
2594 * Description
2595 * Attempt in a safe way to write *len* bytes from the buffer
2596 * *src* to *dst* in memory. It only works for threads that are in
2597 * user context, and *dst* must be a valid user space address.
2598 *
2599 * This helper should not be used to implement any kind of
2600 * security mechanism because of TOC-TOU attacks, but rather to
2601 * debug, divert, and manipulate execution of semi-cooperative
2602 * processes.
2603 *
2604 * Keep in mind that this feature is meant for experiments, and it
2605 * has a risk of crashing the system and running programs.
2606 * Therefore, when an eBPF program using this helper is attached,
2607 * a warning including PID and process name is printed to kernel
2608 * logs.
2609 * Return
2610 * 0 on success, or a negative error in case of failure.
2611 *
2612 * long bpf_current_task_under_cgroup(struct bpf_map *map, u32 index)
2613 * Description
2614 * Check whether the probe is being run is the context of a given
2615 * subset of the cgroup2 hierarchy. The cgroup2 to test is held by
2616 * *map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*.
2617 * Return
2618 * The return value depends on the result of the test, and can be:
2619 *
2620 * * 1, if current task belongs to the cgroup2.
2621 * * 0, if current task does not belong to the cgroup2.
2622 * * A negative error code, if an error occurred.
2623 *
2624 * long bpf_skb_change_tail(struct sk_buff *skb, u32 len, u64 flags)
2625 * Description
2626 * Resize (trim or grow) the packet associated to *skb* to the
2627 * new *len*. The *flags* are reserved for future usage, and must
2628 * be left at zero.
2629 *
2630 * The basic idea is that the helper performs the needed work to
2631 * change the size of the packet, then the eBPF program rewrites
2632 * the rest via helpers like **bpf_skb_store_bytes**\ (),
2633 * **bpf_l3_csum_replace**\ (), **bpf_l3_csum_replace**\ ()
2634 * and others. This helper is a slow path utility intended for
2635 * replies with control messages. And because it is targeted for
2636 * slow path, the helper itself can afford to be slow: it
2637 * implicitly linearizes, unclones and drops offloads from the
2638 * *skb*.
2639 *
2640 * A call to this helper is susceptible to change the underlying
2641 * packet buffer. Therefore, at load time, all checks on pointers
2642 * previously done by the verifier are invalidated and must be
2643 * performed again, if the helper is used in combination with
2644 * direct packet access.
2645 * Return
2646 * 0 on success, or a negative error in case of failure.
2647 *
2648 * long bpf_skb_pull_data(struct sk_buff *skb, u32 len)
2649 * Description
2650 * Pull in non-linear data in case the *skb* is non-linear and not
2651 * all of *len* are part of the linear section. Make *len* bytes
2652 * from *skb* readable and writable. If a zero value is passed for
2653 * *len*, then all bytes in the linear part of *skb* will be made
2654 * readable and writable.
2655 *
2656 * This helper is only needed for reading and writing with direct
2657 * packet access.
2658 *
2659 * For direct packet access, testing that offsets to access
2660 * are within packet boundaries (test on *skb*\ **->data_end**) is
2661 * susceptible to fail if offsets are invalid, or if the requested
2662 * data is in non-linear parts of the *skb*. On failure the
2663 * program can just bail out, or in the case of a non-linear
2664 * buffer, use a helper to make the data available. The
2665 * **bpf_skb_load_bytes**\ () helper is a first solution to access
2666 * the data. Another one consists in using **bpf_skb_pull_data**
2667 * to pull in once the non-linear parts, then retesting and
2668 * eventually access the data.
2669 *
2670 * At the same time, this also makes sure the *skb* is uncloned,
2671 * which is a necessary condition for direct write. As this needs
2672 * to be an invariant for the write part only, the verifier
2673 * detects writes and adds a prologue that is calling
2674 * **bpf_skb_pull_data()** to effectively unclone the *skb* from
2675 * the very beginning in case it is indeed cloned.
2676 *
2677 * A call to this helper is susceptible to change the underlying
2678 * packet buffer. Therefore, at load time, all checks on pointers
2679 * previously done by the verifier are invalidated and must be
2680 * performed again, if the helper is used in combination with
2681 * direct packet access.
2682 * Return
2683 * 0 on success, or a negative error in case of failure.
2684 *
2685 * s64 bpf_csum_update(struct sk_buff *skb, __wsum csum)
2686 * Description
2687 * Add the checksum *csum* into *skb*\ **->csum** in case the
2688 * driver has supplied a checksum for the entire packet into that
2689 * field. Return an error otherwise. This helper is intended to be
2690 * used in combination with **bpf_csum_diff**\ (), in particular
2691 * when the checksum needs to be updated after data has been
2692 * written into the packet through direct packet access.
2693 * Return
2694 * The checksum on success, or a negative error code in case of
2695 * failure.
2696 *
2697 * void bpf_set_hash_invalid(struct sk_buff *skb)
2698 * Description
2699 * Invalidate the current *skb*\ **->hash**. It can be used after
2700 * mangling on headers through direct packet access, in order to
2701 * indicate that the hash is outdated and to trigger a
2702 * recalculation the next time the kernel tries to access this
2703 * hash or when the **bpf_get_hash_recalc**\ () helper is called.
2704 * Return
2705 * void.
2706 *
2707 * long bpf_get_numa_node_id(void)
2708 * Description
2709 * Return the id of the current NUMA node. The primary use case
2710 * for this helper is the selection of sockets for the local NUMA
2711 * node, when the program is attached to sockets using the
2712 * **SO_ATTACH_REUSEPORT_EBPF** option (see also **socket(7)**),
2713 * but the helper is also available to other eBPF program types,
2714 * similarly to **bpf_get_smp_processor_id**\ ().
2715 * Return
2716 * The id of current NUMA node.
2717 *
2718 * long bpf_skb_change_head(struct sk_buff *skb, u32 len, u64 flags)
2719 * Description
2720 * Grows headroom of packet associated to *skb* and adjusts the
2721 * offset of the MAC header accordingly, adding *len* bytes of
2722 * space. It automatically extends and reallocates memory as
2723 * required.
2724 *
2725 * This helper can be used on a layer 3 *skb* to push a MAC header
2726 * for redirection into a layer 2 device.
2727 *
2728 * All values for *flags* are reserved for future usage, and must
2729 * be left at zero.
2730 *
2731 * A call to this helper is susceptible to change the underlying
2732 * packet buffer. Therefore, at load time, all checks on pointers
2733 * previously done by the verifier are invalidated and must be
2734 * performed again, if the helper is used in combination with
2735 * direct packet access.
2736 * Return
2737 * 0 on success, or a negative error in case of failure.
2738 *
2739 * long bpf_xdp_adjust_head(struct xdp_buff *xdp_md, int delta)
2740 * Description
2741 * Adjust (move) *xdp_md*\ **->data** by *delta* bytes. Note that
2742 * it is possible to use a negative value for *delta*. This helper
2743 * can be used to prepare the packet for pushing or popping
2744 * headers.
2745 *
2746 * A call to this helper is susceptible to change the underlying
2747 * packet buffer. Therefore, at load time, all checks on pointers
2748 * previously done by the verifier are invalidated and must be
2749 * performed again, if the helper is used in combination with
2750 * direct packet access.
2751 * Return
2752 * 0 on success, or a negative error in case of failure.
2753 *
2754 * long bpf_probe_read_str(void *dst, u32 size, const void *unsafe_ptr)
2755 * Description
2756 * Copy a NUL terminated string from an unsafe kernel address
2757 * *unsafe_ptr* to *dst*. See **bpf_probe_read_kernel_str**\ () for
2758 * more details.
2759 *
2760 * Generally, use **bpf_probe_read_user_str**\ () or
2761 * **bpf_probe_read_kernel_str**\ () instead.
2762 * Return
2763 * On success, the strictly positive length of the string,
2764 * including the trailing NUL character. On error, a negative
2765 * value.
2766 *
2767 * u64 bpf_get_socket_cookie(struct sk_buff *skb)
2768 * Description
2769 * If the **struct sk_buff** pointed by *skb* has a known socket,
2770 * retrieve the cookie (generated by the kernel) of this socket.
2771 * If no cookie has been set yet, generate a new cookie. Once
2772 * generated, the socket cookie remains stable for the life of the
2773 * socket. This helper can be useful for monitoring per socket
2774 * networking traffic statistics as it provides a global socket
2775 * identifier that can be assumed unique.
2776 * Return
2777 * A 8-byte long unique number on success, or 0 if the socket
2778 * field is missing inside *skb*.
2779 *
2780 * u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx)
2781 * Description
2782 * Equivalent to bpf_get_socket_cookie() helper that accepts
2783 * *skb*, but gets socket from **struct bpf_sock_addr** context.
2784 * Return
2785 * A 8-byte long unique number.
2786 *
2787 * u64 bpf_get_socket_cookie(struct bpf_sock_ops *ctx)
2788 * Description
2789 * Equivalent to **bpf_get_socket_cookie**\ () helper that accepts
2790 * *skb*, but gets socket from **struct bpf_sock_ops** context.
2791 * Return
2792 * A 8-byte long unique number.
2793 *
2794 * u64 bpf_get_socket_cookie(struct sock *sk)
2795 * Description
2796 * Equivalent to **bpf_get_socket_cookie**\ () helper that accepts
2797 * *sk*, but gets socket from a BTF **struct sock**. This helper
2798 * also works for sleepable programs.
2799 * Return
2800 * A 8-byte long unique number or 0 if *sk* is NULL.
2801 *
2802 * u32 bpf_get_socket_uid(struct sk_buff *skb)
2803 * Description
2804 * Get the owner UID of the socked associated to *skb*.
2805 * Return
2806 * The owner UID of the socket associated to *skb*. If the socket
2807 * is **NULL**, or if it is not a full socket (i.e. if it is a
2808 * time-wait or a request socket instead), **overflowuid** value
2809 * is returned (note that **overflowuid** might also be the actual
2810 * UID value for the socket).
2811 *
2812 * long bpf_set_hash(struct sk_buff *skb, u32 hash)
2813 * Description
2814 * Set the full hash for *skb* (set the field *skb*\ **->hash**)
2815 * to value *hash*.
2816 * Return
2817 * 0
2818 *
2819 * long bpf_setsockopt(void *bpf_socket, int level, int optname, void *optval, int optlen)
2820 * Description
2821 * Emulate a call to **setsockopt()** on the socket associated to
2822 * *bpf_socket*, which must be a full socket. The *level* at
2823 * which the option resides and the name *optname* of the option
2824 * must be specified, see **setsockopt(2)** for more information.
2825 * The option value of length *optlen* is pointed by *optval*.
2826 *
2827 * *bpf_socket* should be one of the following:
2828 *
2829 * * **struct bpf_sock_ops** for **BPF_PROG_TYPE_SOCK_OPS**.
2830 * * **struct bpf_sock_addr** for **BPF_CGROUP_INET4_CONNECT**,
2831 * **BPF_CGROUP_INET6_CONNECT** and **BPF_CGROUP_UNIX_CONNECT**.
2832 *
2833 * This helper actually implements a subset of **setsockopt()**.
2834 * It supports the following *level*\ s:
2835 *
2836 * * **SOL_SOCKET**, which supports the following *optname*\ s:
2837 * **SO_RCVBUF**, **SO_SNDBUF**, **SO_MAX_PACING_RATE**,
2838 * **SO_PRIORITY**, **SO_RCVLOWAT**, **SO_MARK**,
2839 * **SO_BINDTODEVICE**, **SO_KEEPALIVE**, **SO_REUSEADDR**,
2840 * **SO_REUSEPORT**, **SO_BINDTOIFINDEX**, **SO_TXREHASH**.
2841 * * **IPPROTO_TCP**, which supports the following *optname*\ s:
2842 * **TCP_CONGESTION**, **TCP_BPF_IW**,
2843 * **TCP_BPF_SNDCWND_CLAMP**, **TCP_SAVE_SYN**,
2844 * **TCP_KEEPIDLE**, **TCP_KEEPINTVL**, **TCP_KEEPCNT**,
2845 * **TCP_SYNCNT**, **TCP_USER_TIMEOUT**, **TCP_NOTSENT_LOWAT**,
2846 * **TCP_NODELAY**, **TCP_MAXSEG**, **TCP_WINDOW_CLAMP**,
2847 * **TCP_THIN_LINEAR_TIMEOUTS**, **TCP_BPF_DELACK_MAX**,
2848 * **TCP_BPF_RTO_MIN**.
2849 * * **IPPROTO_IP**, which supports *optname* **IP_TOS**.
2850 * * **IPPROTO_IPV6**, which supports the following *optname*\ s:
2851 * **IPV6_TCLASS**, **IPV6_AUTOFLOWLABEL**.
2852 * Return
2853 * 0 on success, or a negative error in case of failure.
2854 *
2855 * long bpf_skb_adjust_room(struct sk_buff *skb, s32 len_diff, u32 mode, u64 flags)
2856 * Description
2857 * Grow or shrink the room for data in the packet associated to
2858 * *skb* by *len_diff*, and according to the selected *mode*.
2859 *
2860 * By default, the helper will reset any offloaded checksum
2861 * indicator of the skb to CHECKSUM_NONE. This can be avoided
2862 * by the following flag:
2863 *
2864 * * **BPF_F_ADJ_ROOM_NO_CSUM_RESET**: Do not reset offloaded
2865 * checksum data of the skb to CHECKSUM_NONE.
2866 *
2867 * There are two supported modes at this time:
2868 *
2869 * * **BPF_ADJ_ROOM_MAC**: Adjust room at the mac layer
2870 * (room space is added or removed between the layer 2 and
2871 * layer 3 headers).
2872 *
2873 * * **BPF_ADJ_ROOM_NET**: Adjust room at the network layer
2874 * (room space is added or removed between the layer 3 and
2875 * layer 4 headers).
2876 *
2877 * The following flags are supported at this time:
2878 *
2879 * * **BPF_F_ADJ_ROOM_FIXED_GSO**: Do not adjust gso_size.
2880 * Adjusting mss in this way is not allowed for datagrams.
2881 *
2882 * * **BPF_F_ADJ_ROOM_ENCAP_L3_IPV4**,
2883 * **BPF_F_ADJ_ROOM_ENCAP_L3_IPV6**:
2884 * Any new space is reserved to hold a tunnel header.
2885 * Configure skb offsets and other fields accordingly.
2886 *
2887 * * **BPF_F_ADJ_ROOM_ENCAP_L4_GRE**,
2888 * **BPF_F_ADJ_ROOM_ENCAP_L4_UDP**:
2889 * Use with ENCAP_L3 flags to further specify the tunnel type.
2890 *
2891 * * **BPF_F_ADJ_ROOM_ENCAP_L2**\ (*len*):
2892 * Use with ENCAP_L3/L4 flags to further specify the tunnel
2893 * type; *len* is the length of the inner MAC header.
2894 *
2895 * * **BPF_F_ADJ_ROOM_ENCAP_L2_ETH**:
2896 * Use with BPF_F_ADJ_ROOM_ENCAP_L2 flag to further specify the
2897 * L2 type as Ethernet.
2898 *
2899 * * **BPF_F_ADJ_ROOM_DECAP_L3_IPV4**,
2900 * **BPF_F_ADJ_ROOM_DECAP_L3_IPV6**:
2901 * Indicate the new IP header version after decapsulating the outer
2902 * IP header. Used when the inner and outer IP versions are different.
2903 *
2904 * A call to this helper is susceptible to change the underlying
2905 * packet buffer. Therefore, at load time, all checks on pointers
2906 * previously done by the verifier are invalidated and must be
2907 * performed again, if the helper is used in combination with
2908 * direct packet access.
2909 * Return
2910 * 0 on success, or a negative error in case of failure.
2911 *
2912 * long bpf_redirect_map(struct bpf_map *map, u64 key, u64 flags)
2913 * Description
2914 * Redirect the packet to the endpoint referenced by *map* at
2915 * index *key*. Depending on its type, this *map* can contain
2916 * references to net devices (for forwarding packets through other
2917 * ports), or to CPUs (for redirecting XDP frames to another CPU;
2918 * but this is only implemented for native XDP (with driver
2919 * support) as of this writing).
2920 *
2921 * The lower two bits of *flags* are used as the return code if
2922 * the map lookup fails. This is so that the return value can be
2923 * one of the XDP program return codes up to **XDP_TX**, as chosen
2924 * by the caller. The higher bits of *flags* can be set to
2925 * BPF_F_BROADCAST or BPF_F_EXCLUDE_INGRESS as defined below.
2926 *
2927 * With BPF_F_BROADCAST the packet will be broadcasted to all the
2928 * interfaces in the map, with BPF_F_EXCLUDE_INGRESS the ingress
2929 * interface will be excluded when do broadcasting.
2930 *
2931 * See also **bpf_redirect**\ (), which only supports redirecting
2932 * to an ifindex, but doesn't require a map to do so.
2933 * Return
2934 * **XDP_REDIRECT** on success, or the value of the two lower bits
2935 * of the *flags* argument on error.
2936 *
2937 * long bpf_sk_redirect_map(struct sk_buff *skb, struct bpf_map *map, u32 key, u64 flags)
2938 * Description
2939 * Redirect the packet to the socket referenced by *map* (of type
2940 * **BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
2941 * egress interfaces can be used for redirection. The
2942 * **BPF_F_INGRESS** value in *flags* is used to make the
2943 * distinction (ingress path is selected if the flag is present,
2944 * egress path otherwise). This is the only flag supported for now.
2945 * Return
2946 * **SK_PASS** on success, or **SK_DROP** on error.
2947 *
2948 * long bpf_sock_map_update(struct bpf_sock_ops *skops, struct bpf_map *map, void *key, u64 flags)
2949 * Description
2950 * Add an entry to, or update a *map* referencing sockets. The
2951 * *skops* is used as a new value for the entry associated to
2952 * *key*. *flags* is one of:
2953 *
2954 * **BPF_NOEXIST**
2955 * The entry for *key* must not exist in the map.
2956 * **BPF_EXIST**
2957 * The entry for *key* must already exist in the map.
2958 * **BPF_ANY**
2959 * No condition on the existence of the entry for *key*.
2960 *
2961 * If the *map* has eBPF programs (parser and verdict), those will
2962 * be inherited by the socket being added. If the socket is
2963 * already attached to eBPF programs, this results in an error.
2964 * Return
2965 * 0 on success, or a negative error in case of failure.
2966 *
2967 * long bpf_xdp_adjust_meta(struct xdp_buff *xdp_md, int delta)
2968 * Description
2969 * Adjust the address pointed by *xdp_md*\ **->data_meta** by
2970 * *delta* (which can be positive or negative). Note that this
2971 * operation modifies the address stored in *xdp_md*\ **->data**,
2972 * so the latter must be loaded only after the helper has been
2973 * called.
2974 *
2975 * The use of *xdp_md*\ **->data_meta** is optional and programs
2976 * are not required to use it. The rationale is that when the
2977 * packet is processed with XDP (e.g. as DoS filter), it is
2978 * possible to push further meta data along with it before passing
2979 * to the stack, and to give the guarantee that an ingress eBPF
2980 * program attached as a TC classifier on the same device can pick
2981 * this up for further post-processing. Since TC works with socket
2982 * buffers, it remains possible to set from XDP the **mark** or
2983 * **priority** pointers, or other pointers for the socket buffer.
2984 * Having this scratch space generic and programmable allows for
2985 * more flexibility as the user is free to store whatever meta
2986 * data they need.
2987 *
2988 * A call to this helper is susceptible to change the underlying
2989 * packet buffer. Therefore, at load time, all checks on pointers
2990 * previously done by the verifier are invalidated and must be
2991 * performed again, if the helper is used in combination with
2992 * direct packet access.
2993 * Return
2994 * 0 on success, or a negative error in case of failure.
2995 *
2996 * long bpf_perf_event_read_value(struct bpf_map *map, u64 flags, struct bpf_perf_event_value *buf, u32 buf_size)
2997 * Description
2998 * Read the value of a perf event counter, and store it into *buf*
2999 * of size *buf_size*. This helper relies on a *map* of type
3000 * **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of the perf event
3001 * counter is selected when *map* is updated with perf event file
3002 * descriptors. The *map* is an array whose size is the number of
3003 * available CPUs, and each cell contains a value relative to one
3004 * CPU. The value to retrieve is indicated by *flags*, that
3005 * contains the index of the CPU to look up, masked with
3006 * **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to
3007 * **BPF_F_CURRENT_CPU** to indicate that the value for the
3008 * current CPU should be retrieved.
3009 *
3010 * This helper behaves in a way close to
3011 * **bpf_perf_event_read**\ () helper, save that instead of
3012 * just returning the value observed, it fills the *buf*
3013 * structure. This allows for additional data to be retrieved: in
3014 * particular, the enabled and running times (in *buf*\
3015 * **->enabled** and *buf*\ **->running**, respectively) are
3016 * copied. In general, **bpf_perf_event_read_value**\ () is
3017 * recommended over **bpf_perf_event_read**\ (), which has some
3018 * ABI issues and provides fewer functionalities.
3019 *
3020 * These values are interesting, because hardware PMU (Performance
3021 * Monitoring Unit) counters are limited resources. When there are
3022 * more PMU based perf events opened than available counters,
3023 * kernel will multiplex these events so each event gets certain
3024 * percentage (but not all) of the PMU time. In case that
3025 * multiplexing happens, the number of samples or counter value
3026 * will not reflect the case compared to when no multiplexing
3027 * occurs. This makes comparison between different runs difficult.
3028 * Typically, the counter value should be normalized before
3029 * comparing to other experiments. The usual normalization is done
3030 * as follows.
3031 *
3032 * ::
3033 *
3034 * normalized_counter = counter * t_enabled / t_running
3035 *
3036 * Where t_enabled is the time enabled for event and t_running is
3037 * the time running for event since last normalization. The
3038 * enabled and running times are accumulated since the perf event
3039 * open. To achieve scaling factor between two invocations of an
3040 * eBPF program, users can use CPU id as the key (which is
3041 * typical for perf array usage model) to remember the previous
3042 * value and do the calculation inside the eBPF program.
3043 * Return
3044 * 0 on success, or a negative error in case of failure.
3045 *
3046 * long bpf_perf_prog_read_value(struct bpf_perf_event_data *ctx, struct bpf_perf_event_value *buf, u32 buf_size)
3047 * Description
3048 * For an eBPF program attached to a perf event, retrieve the
3049 * value of the event counter associated to *ctx* and store it in
3050 * the structure pointed by *buf* and of size *buf_size*. Enabled
3051 * and running times are also stored in the structure (see
3052 * description of helper **bpf_perf_event_read_value**\ () for
3053 * more details).
3054 * Return
3055 * 0 on success, or a negative error in case of failure.
3056 *
3057 * long bpf_getsockopt(void *bpf_socket, int level, int optname, void *optval, int optlen)
3058 * Description
3059 * Emulate a call to **getsockopt()** on the socket associated to
3060 * *bpf_socket*, which must be a full socket. The *level* at
3061 * which the option resides and the name *optname* of the option
3062 * must be specified, see **getsockopt(2)** for more information.
3063 * The retrieved value is stored in the structure pointed by
3064 * *opval* and of length *optlen*.
3065 *
3066 * *bpf_socket* should be one of the following:
3067 *
3068 * * **struct bpf_sock_ops** for **BPF_PROG_TYPE_SOCK_OPS**.
3069 * * **struct bpf_sock_addr** for **BPF_CGROUP_INET4_CONNECT**,
3070 * **BPF_CGROUP_INET6_CONNECT** and **BPF_CGROUP_UNIX_CONNECT**.
3071 *
3072 * This helper actually implements a subset of **getsockopt()**.
3073 * It supports the same set of *optname*\ s that is supported by
3074 * the **bpf_setsockopt**\ () helper. The exceptions are
3075 * **TCP_BPF_*** is **bpf_setsockopt**\ () only and
3076 * **TCP_SAVED_SYN** is **bpf_getsockopt**\ () only.
3077 * Return
3078 * 0 on success, or a negative error in case of failure.
3079 *
3080 * long bpf_override_return(struct pt_regs *regs, u64 rc)
3081 * Description
3082 * Used for error injection, this helper uses kprobes to override
3083 * the return value of the probed function, and to set it to *rc*.
3084 * The first argument is the context *regs* on which the kprobe
3085 * works.
3086 *
3087 * This helper works by setting the PC (program counter)
3088 * to an override function which is run in place of the original
3089 * probed function. This means the probed function is not run at
3090 * all. The replacement function just returns with the required
3091 * value.
3092 *
3093 * This helper has security implications, and thus is subject to
3094 * restrictions. It is only available if the kernel was compiled
3095 * with the **CONFIG_BPF_KPROBE_OVERRIDE** configuration
3096 * option, and in this case it only works on functions tagged with
3097 * **ALLOW_ERROR_INJECTION** in the kernel code.
3098 *
3099 * Also, the helper is only available for the architectures having
3100 * the CONFIG_FUNCTION_ERROR_INJECTION option. As of this writing,
3101 * x86 architecture is the only one to support this feature.
3102 * Return
3103 * 0
3104 *
3105 * long bpf_sock_ops_cb_flags_set(struct bpf_sock_ops *bpf_sock, int argval)
3106 * Description
3107 * Attempt to set the value of the **bpf_sock_ops_cb_flags** field
3108 * for the full TCP socket associated to *bpf_sock_ops* to
3109 * *argval*.
3110 *
3111 * The primary use of this field is to determine if there should
3112 * be calls to eBPF programs of type
3113 * **BPF_PROG_TYPE_SOCK_OPS** at various points in the TCP
3114 * code. A program of the same type can change its value, per
3115 * connection and as necessary, when the connection is
3116 * established. This field is directly accessible for reading, but
3117 * this helper must be used for updates in order to return an
3118 * error if an eBPF program tries to set a callback that is not
3119 * supported in the current kernel.
3120 *
3121 * *argval* is a flag array which can combine these flags:
3122 *
3123 * * **BPF_SOCK_OPS_RTO_CB_FLAG** (retransmission time out)
3124 * * **BPF_SOCK_OPS_RETRANS_CB_FLAG** (retransmission)
3125 * * **BPF_SOCK_OPS_STATE_CB_FLAG** (TCP state change)
3126 * * **BPF_SOCK_OPS_RTT_CB_FLAG** (every RTT)
3127 *
3128 * Therefore, this function can be used to clear a callback flag by
3129 * setting the appropriate bit to zero. e.g. to disable the RTO
3130 * callback:
3131 *
3132 * **bpf_sock_ops_cb_flags_set(bpf_sock,**
3133 * **bpf_sock->bpf_sock_ops_cb_flags & ~BPF_SOCK_OPS_RTO_CB_FLAG)**
3134 *
3135 * Here are some examples of where one could call such eBPF
3136 * program:
3137 *
3138 * * When RTO fires.
3139 * * When a packet is retransmitted.
3140 * * When the connection terminates.
3141 * * When a packet is sent.
3142 * * When a packet is received.
3143 * Return
3144 * Code **-EINVAL** if the socket is not a full TCP socket;
3145 * otherwise, a positive number containing the bits that could not
3146 * be set is returned (which comes down to 0 if all bits were set
3147 * as required).
3148 *
3149 * long bpf_msg_redirect_map(struct sk_msg_buff *msg, struct bpf_map *map, u32 key, u64 flags)
3150 * Description
3151 * This helper is used in programs implementing policies at the
3152 * socket level. If the message *msg* is allowed to pass (i.e. if
3153 * the verdict eBPF program returns **SK_PASS**), redirect it to
3154 * the socket referenced by *map* (of type
3155 * **BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
3156 * egress interfaces can be used for redirection. The
3157 * **BPF_F_INGRESS** value in *flags* is used to make the
3158 * distinction (ingress path is selected if the flag is present,
3159 * egress path otherwise). This is the only flag supported for now.
3160 * Return
3161 * **SK_PASS** on success, or **SK_DROP** on error.
3162 *
3163 * long bpf_msg_apply_bytes(struct sk_msg_buff *msg, u32 bytes)
3164 * Description
3165 * For socket policies, apply the verdict of the eBPF program to
3166 * the next *bytes* (number of bytes) of message *msg*.
3167 *
3168 * For example, this helper can be used in the following cases:
3169 *
3170 * * A single **sendmsg**\ () or **sendfile**\ () system call
3171 * contains multiple logical messages that the eBPF program is
3172 * supposed to read and for which it should apply a verdict.
3173 * * An eBPF program only cares to read the first *bytes* of a
3174 * *msg*. If the message has a large payload, then setting up
3175 * and calling the eBPF program repeatedly for all bytes, even
3176 * though the verdict is already known, would create unnecessary
3177 * overhead.
3178 *
3179 * When called from within an eBPF program, the helper sets a
3180 * counter internal to the BPF infrastructure, that is used to
3181 * apply the last verdict to the next *bytes*. If *bytes* is
3182 * smaller than the current data being processed from a
3183 * **sendmsg**\ () or **sendfile**\ () system call, the first
3184 * *bytes* will be sent and the eBPF program will be re-run with
3185 * the pointer for start of data pointing to byte number *bytes*
3186 * **+ 1**. If *bytes* is larger than the current data being
3187 * processed, then the eBPF verdict will be applied to multiple
3188 * **sendmsg**\ () or **sendfile**\ () calls until *bytes* are
3189 * consumed.
3190 *
3191 * Note that if a socket closes with the internal counter holding
3192 * a non-zero value, this is not a problem because data is not
3193 * being buffered for *bytes* and is sent as it is received.
3194 * Return
3195 * 0
3196 *
3197 * long bpf_msg_cork_bytes(struct sk_msg_buff *msg, u32 bytes)
3198 * Description
3199 * For socket policies, prevent the execution of the verdict eBPF
3200 * program for message *msg* until *bytes* (byte number) have been
3201 * accumulated.
3202 *
3203 * This can be used when one needs a specific number of bytes
3204 * before a verdict can be assigned, even if the data spans
3205 * multiple **sendmsg**\ () or **sendfile**\ () calls. The extreme
3206 * case would be a user calling **sendmsg**\ () repeatedly with
3207 * 1-byte long message segments. Obviously, this is bad for
3208 * performance, but it is still valid. If the eBPF program needs
3209 * *bytes* bytes to validate a header, this helper can be used to
3210 * prevent the eBPF program to be called again until *bytes* have
3211 * been accumulated.
3212 * Return
3213 * 0
3214 *
3215 * long bpf_msg_pull_data(struct sk_msg_buff *msg, u32 start, u32 end, u64 flags)
3216 * Description
3217 * For socket policies, pull in non-linear data from user space
3218 * for *msg* and set pointers *msg*\ **->data** and *msg*\
3219 * **->data_end** to *start* and *end* bytes offsets into *msg*,
3220 * respectively.
3221 *
3222 * If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a
3223 * *msg* it can only parse data that the (**data**, **data_end**)
3224 * pointers have already consumed. For **sendmsg**\ () hooks this
3225 * is likely the first scatterlist element. But for calls relying
3226 * on the **sendpage** handler (e.g. **sendfile**\ ()) this will
3227 * be the range (**0**, **0**) because the data is shared with
3228 * user space and by default the objective is to avoid allowing
3229 * user space to modify data while (or after) eBPF verdict is
3230 * being decided. This helper can be used to pull in data and to
3231 * set the start and end pointer to given values. Data will be
3232 * copied if necessary (i.e. if data was not linear and if start
3233 * and end pointers do not point to the same chunk).
3234 *
3235 * A call to this helper is susceptible to change the underlying
3236 * packet buffer. Therefore, at load time, all checks on pointers
3237 * previously done by the verifier are invalidated and must be
3238 * performed again, if the helper is used in combination with
3239 * direct packet access.
3240 *
3241 * All values for *flags* are reserved for future usage, and must
3242 * be left at zero.
3243 * Return
3244 * 0 on success, or a negative error in case of failure.
3245 *
3246 * long bpf_bind(struct bpf_sock_addr *ctx, struct sockaddr *addr, int addr_len)
3247 * Description
3248 * Bind the socket associated to *ctx* to the address pointed by
3249 * *addr*, of length *addr_len*. This allows for making outgoing
3250 * connection from the desired IP address, which can be useful for
3251 * example when all processes inside a cgroup should use one
3252 * single IP address on a host that has multiple IP configured.
3253 *
3254 * This helper works for IPv4 and IPv6, TCP and UDP sockets. The
3255 * domain (*addr*\ **->sa_family**) must be **AF_INET** (or
3256 * **AF_INET6**). It's advised to pass zero port (**sin_port**
3257 * or **sin6_port**) which triggers IP_BIND_ADDRESS_NO_PORT-like
3258 * behavior and lets the kernel efficiently pick up an unused
3259 * port as long as 4-tuple is unique. Passing non-zero port might
3260 * lead to degraded performance.
3261 * Return
3262 * 0 on success, or a negative error in case of failure.
3263 *
3264 * long bpf_xdp_adjust_tail(struct xdp_buff *xdp_md, int delta)
3265 * Description
3266 * Adjust (move) *xdp_md*\ **->data_end** by *delta* bytes. It is
3267 * possible to both shrink and grow the packet tail.
3268 * Shrink done via *delta* being a negative integer.
3269 *
3270 * A call to this helper is susceptible to change the underlying
3271 * packet buffer. Therefore, at load time, all checks on pointers
3272 * previously done by the verifier are invalidated and must be
3273 * performed again, if the helper is used in combination with
3274 * direct packet access.
3275 * Return
3276 * 0 on success, or a negative error in case of failure.
3277 *
3278 * long bpf_skb_get_xfrm_state(struct sk_buff *skb, u32 index, struct bpf_xfrm_state *xfrm_state, u32 size, u64 flags)
3279 * Description
3280 * Retrieve the XFRM state (IP transform framework, see also
3281 * **ip-xfrm(8)**) at *index* in XFRM "security path" for *skb*.
3282 *
3283 * The retrieved value is stored in the **struct bpf_xfrm_state**
3284 * pointed by *xfrm_state* and of length *size*.
3285 *
3286 * All values for *flags* are reserved for future usage, and must
3287 * be left at zero.
3288 *
3289 * This helper is available only if the kernel was compiled with
3290 * **CONFIG_XFRM** configuration option.
3291 * Return
3292 * 0 on success, or a negative error in case of failure.
3293 *
3294 * long bpf_get_stack(void *ctx, void *buf, u32 size, u64 flags)
3295 * Description
3296 * Return a user or a kernel stack in bpf program provided buffer.
3297 * To achieve this, the helper needs *ctx*, which is a pointer
3298 * to the context on which the tracing program is executed.
3299 * To store the stacktrace, the bpf program provides *buf* with
3300 * a nonnegative *size*.
3301 *
3302 * The last argument, *flags*, holds the number of stack frames to
3303 * skip (from 0 to 255), masked with
3304 * **BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set
3305 * the following flags:
3306 *
3307 * **BPF_F_USER_STACK**
3308 * Collect a user space stack instead of a kernel stack.
3309 * **BPF_F_USER_BUILD_ID**
3310 * Collect (build_id, file_offset) instead of ips for user
3311 * stack, only valid if **BPF_F_USER_STACK** is also
3312 * specified.
3313 *
3314 * *file_offset* is an offset relative to the beginning
3315 * of the executable or shared object file backing the vma
3316 * which the *ip* falls in. It is *not* an offset relative
3317 * to that object's base address. Accordingly, it must be
3318 * adjusted by adding (sh_addr - sh_offset), where
3319 * sh_{addr,offset} correspond to the executable section
3320 * containing *file_offset* in the object, for comparisons
3321 * to symbols' st_value to be valid.
3322 *
3323 * **bpf_get_stack**\ () can collect up to
3324 * **PERF_MAX_STACK_DEPTH** both kernel and user frames, subject
3325 * to sufficient large buffer size. Note that
3326 * this limit can be controlled with the **sysctl** program, and
3327 * that it should be manually increased in order to profile long
3328 * user stacks (such as stacks for Java programs). To do so, use:
3329 *
3330 * ::
3331 *
3332 * # sysctl kernel.perf_event_max_stack=<new value>
3333 * Return
3334 * The non-negative copied *buf* length equal to or less than
3335 * *size* on success, or a negative error in case of failure.
3336 *
3337 * long bpf_skb_load_bytes_relative(const void *skb, u32 offset, void *to, u32 len, u32 start_header)
3338 * Description
3339 * This helper is similar to **bpf_skb_load_bytes**\ () in that
3340 * it provides an easy way to load *len* bytes from *offset*
3341 * from the packet associated to *skb*, into the buffer pointed
3342 * by *to*. The difference to **bpf_skb_load_bytes**\ () is that
3343 * a fifth argument *start_header* exists in order to select a
3344 * base offset to start from. *start_header* can be one of:
3345 *
3346 * **BPF_HDR_START_MAC**
3347 * Base offset to load data from is *skb*'s mac header.
3348 * **BPF_HDR_START_NET**
3349 * Base offset to load data from is *skb*'s network header.
3350 *
3351 * In general, "direct packet access" is the preferred method to
3352 * access packet data, however, this helper is in particular useful
3353 * in socket filters where *skb*\ **->data** does not always point
3354 * to the start of the mac header and where "direct packet access"
3355 * is not available.
3356 * Return
3357 * 0 on success, or a negative error in case of failure.
3358 *
3359 * long bpf_fib_lookup(void *ctx, struct bpf_fib_lookup *params, int plen, u32 flags)
3360 * Description
3361 * Do FIB lookup in kernel tables using parameters in *params*.
3362 * If lookup is successful and result shows packet is to be
3363 * forwarded, the neighbor tables are searched for the nexthop.
3364 * If successful (ie., FIB lookup shows forwarding and nexthop
3365 * is resolved), the nexthop address is returned in ipv4_dst
3366 * or ipv6_dst based on family, smac is set to mac address of
3367 * egress device, dmac is set to nexthop mac address, rt_metric
3368 * is set to metric from route (IPv4/IPv6 only), and ifindex
3369 * is set to the device index of the nexthop from the FIB lookup.
3370 *
3371 * *plen* argument is the size of the passed in struct.
3372 * *flags* argument can be a combination of one or more of the
3373 * following values:
3374 *
3375 * **BPF_FIB_LOOKUP_DIRECT**
3376 * Do a direct table lookup vs full lookup using FIB
3377 * rules.
3378 * **BPF_FIB_LOOKUP_TBID**
3379 * Used with BPF_FIB_LOOKUP_DIRECT.
3380 * Use the routing table ID present in *params*->tbid
3381 * for the fib lookup.
3382 * **BPF_FIB_LOOKUP_OUTPUT**
3383 * Perform lookup from an egress perspective (default is
3384 * ingress).
3385 * **BPF_FIB_LOOKUP_SKIP_NEIGH**
3386 * Skip the neighbour table lookup. *params*->dmac
3387 * and *params*->smac will not be set as output. A common
3388 * use case is to call **bpf_redirect_neigh**\ () after
3389 * doing **bpf_fib_lookup**\ ().
3390 * **BPF_FIB_LOOKUP_SRC**
3391 * Derive and set source IP addr in *params*->ipv{4,6}_src
3392 * for the nexthop. If the src addr cannot be derived,
3393 * **BPF_FIB_LKUP_RET_NO_SRC_ADDR** is returned. In this
3394 * case, *params*->dmac and *params*->smac are not set either.
3395 *
3396 * *ctx* is either **struct xdp_md** for XDP programs or
3397 * **struct sk_buff** tc cls_act programs.
3398 * Return
3399 * * < 0 if any input argument is invalid
3400 * * 0 on success (packet is forwarded, nexthop neighbor exists)
3401 * * > 0 one of **BPF_FIB_LKUP_RET_** codes explaining why the
3402 * packet is not forwarded or needs assist from full stack
3403 *
3404 * If lookup fails with BPF_FIB_LKUP_RET_FRAG_NEEDED, then the MTU
3405 * was exceeded and output params->mtu_result contains the MTU.
3406 *
3407 * long bpf_sock_hash_update(struct bpf_sock_ops *skops, struct bpf_map *map, void *key, u64 flags)
3408 * Description
3409 * Add an entry to, or update a sockhash *map* referencing sockets.
3410 * The *skops* is used as a new value for the entry associated to
3411 * *key*. *flags* is one of:
3412 *
3413 * **BPF_NOEXIST**
3414 * The entry for *key* must not exist in the map.
3415 * **BPF_EXIST**
3416 * The entry for *key* must already exist in the map.
3417 * **BPF_ANY**
3418 * No condition on the existence of the entry for *key*.
3419 *
3420 * If the *map* has eBPF programs (parser and verdict), those will
3421 * be inherited by the socket being added. If the socket is
3422 * already attached to eBPF programs, this results in an error.
3423 * Return
3424 * 0 on success, or a negative error in case of failure.
3425 *
3426 * long bpf_msg_redirect_hash(struct sk_msg_buff *msg, struct bpf_map *map, void *key, u64 flags)
3427 * Description
3428 * This helper is used in programs implementing policies at the
3429 * socket level. If the message *msg* is allowed to pass (i.e. if
3430 * the verdict eBPF program returns **SK_PASS**), redirect it to
3431 * the socket referenced by *map* (of type
3432 * **BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and
3433 * egress interfaces can be used for redirection. The
3434 * **BPF_F_INGRESS** value in *flags* is used to make the
3435 * distinction (ingress path is selected if the flag is present,
3436 * egress path otherwise). This is the only flag supported for now.
3437 * Return
3438 * **SK_PASS** on success, or **SK_DROP** on error.
3439 *
3440 * long bpf_sk_redirect_hash(struct sk_buff *skb, struct bpf_map *map, void *key, u64 flags)
3441 * Description
3442 * This helper is used in programs implementing policies at the
3443 * skb socket level. If the sk_buff *skb* is allowed to pass (i.e.
3444 * if the verdict eBPF program returns **SK_PASS**), redirect it
3445 * to the socket referenced by *map* (of type
3446 * **BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and
3447 * egress interfaces can be used for redirection. The
3448 * **BPF_F_INGRESS** value in *flags* is used to make the
3449 * distinction (ingress path is selected if the flag is present,
3450 * egress otherwise). This is the only flag supported for now.
3451 * Return
3452 * **SK_PASS** on success, or **SK_DROP** on error.
3453 *
3454 * long bpf_lwt_push_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
3455 * Description
3456 * Encapsulate the packet associated to *skb* within a Layer 3
3457 * protocol header. This header is provided in the buffer at
3458 * address *hdr*, with *len* its size in bytes. *type* indicates
3459 * the protocol of the header and can be one of:
3460 *
3461 * **BPF_LWT_ENCAP_SEG6**
3462 * IPv6 encapsulation with Segment Routing Header
3463 * (**struct ipv6_sr_hdr**). *hdr* only contains the SRH,
3464 * the IPv6 header is computed by the kernel.
3465 * **BPF_LWT_ENCAP_SEG6_INLINE**
3466 * Only works if *skb* contains an IPv6 packet. Insert a
3467 * Segment Routing Header (**struct ipv6_sr_hdr**) inside
3468 * the IPv6 header.
3469 * **BPF_LWT_ENCAP_IP**
3470 * IP encapsulation (GRE/GUE/IPIP/etc). The outer header
3471 * must be IPv4 or IPv6, followed by zero or more
3472 * additional headers, up to **LWT_BPF_MAX_HEADROOM**
3473 * total bytes in all prepended headers. Please note that
3474 * if **skb_is_gso**\ (*skb*) is true, no more than two
3475 * headers can be prepended, and the inner header, if
3476 * present, should be either GRE or UDP/GUE.
3477 *
3478 * **BPF_LWT_ENCAP_SEG6**\ \* types can be called by BPF programs
3479 * of type **BPF_PROG_TYPE_LWT_IN**; **BPF_LWT_ENCAP_IP** type can
3480 * be called by bpf programs of types **BPF_PROG_TYPE_LWT_IN** and
3481 * **BPF_PROG_TYPE_LWT_XMIT**.
3482 *
3483 * A call to this helper is susceptible to change the underlying
3484 * packet buffer. Therefore, at load time, all checks on pointers
3485 * previously done by the verifier are invalidated and must be
3486 * performed again, if the helper is used in combination with
3487 * direct packet access.
3488 * Return
3489 * 0 on success, or a negative error in case of failure.
3490 *
3491 * long bpf_lwt_seg6_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len)
3492 * Description
3493 * Store *len* bytes from address *from* into the packet
3494 * associated to *skb*, at *offset*. Only the flags, tag and TLVs
3495 * inside the outermost IPv6 Segment Routing Header can be
3496 * modified through this helper.
3497 *
3498 * A call to this helper is susceptible to change the underlying
3499 * packet buffer. Therefore, at load time, all checks on pointers
3500 * previously done by the verifier are invalidated and must be
3501 * performed again, if the helper is used in combination with
3502 * direct packet access.
3503 * Return
3504 * 0 on success, or a negative error in case of failure.
3505 *
3506 * long bpf_lwt_seg6_adjust_srh(struct sk_buff *skb, u32 offset, s32 delta)
3507 * Description
3508 * Adjust the size allocated to TLVs in the outermost IPv6
3509 * Segment Routing Header contained in the packet associated to
3510 * *skb*, at position *offset* by *delta* bytes. Only offsets
3511 * after the segments are accepted. *delta* can be as well
3512 * positive (growing) as negative (shrinking).
3513 *
3514 * A call to this helper is susceptible to change the underlying
3515 * packet buffer. Therefore, at load time, all checks on pointers
3516 * previously done by the verifier are invalidated and must be
3517 * performed again, if the helper is used in combination with
3518 * direct packet access.
3519 * Return
3520 * 0 on success, or a negative error in case of failure.
3521 *
3522 * long bpf_lwt_seg6_action(struct sk_buff *skb, u32 action, void *param, u32 param_len)
3523 * Description
3524 * Apply an IPv6 Segment Routing action of type *action* to the
3525 * packet associated to *skb*. Each action takes a parameter
3526 * contained at address *param*, and of length *param_len* bytes.
3527 * *action* can be one of:
3528 *
3529 * **SEG6_LOCAL_ACTION_END_X**
3530 * End.X action: Endpoint with Layer-3 cross-connect.
3531 * Type of *param*: **struct in6_addr**.
3532 * **SEG6_LOCAL_ACTION_END_T**
3533 * End.T action: Endpoint with specific IPv6 table lookup.
3534 * Type of *param*: **int**.
3535 * **SEG6_LOCAL_ACTION_END_B6**
3536 * End.B6 action: Endpoint bound to an SRv6 policy.
3537 * Type of *param*: **struct ipv6_sr_hdr**.
3538 * **SEG6_LOCAL_ACTION_END_B6_ENCAP**
3539 * End.B6.Encap action: Endpoint bound to an SRv6
3540 * encapsulation policy.
3541 * Type of *param*: **struct ipv6_sr_hdr**.
3542 *
3543 * A call to this helper is susceptible to change the underlying
3544 * packet buffer. Therefore, at load time, all checks on pointers
3545 * previously done by the verifier are invalidated and must be
3546 * performed again, if the helper is used in combination with
3547 * direct packet access.
3548 * Return
3549 * 0 on success, or a negative error in case of failure.
3550 *
3551 * long bpf_rc_repeat(void *ctx)
3552 * Description
3553 * This helper is used in programs implementing IR decoding, to
3554 * report a successfully decoded repeat key message. This delays
3555 * the generation of a key up event for previously generated
3556 * key down event.
3557 *
3558 * Some IR protocols like NEC have a special IR message for
3559 * repeating last button, for when a button is held down.
3560 *
3561 * The *ctx* should point to the lirc sample as passed into
3562 * the program.
3563 *
3564 * This helper is only available is the kernel was compiled with
3565 * the **CONFIG_BPF_LIRC_MODE2** configuration option set to
3566 * "**y**".
3567 * Return
3568 * 0
3569 *
3570 * long bpf_rc_keydown(void *ctx, u32 protocol, u64 scancode, u32 toggle)
3571 * Description
3572 * This helper is used in programs implementing IR decoding, to
3573 * report a successfully decoded key press with *scancode*,
3574 * *toggle* value in the given *protocol*. The scancode will be
3575 * translated to a keycode using the rc keymap, and reported as
3576 * an input key down event. After a period a key up event is
3577 * generated. This period can be extended by calling either
3578 * **bpf_rc_keydown**\ () again with the same values, or calling
3579 * **bpf_rc_repeat**\ ().
3580 *
3581 * Some protocols include a toggle bit, in case the button was
3582 * released and pressed again between consecutive scancodes.
3583 *
3584 * The *ctx* should point to the lirc sample as passed into
3585 * the program.
3586 *
3587 * The *protocol* is the decoded protocol number (see
3588 * **enum rc_proto** for some predefined values).
3589 *
3590 * This helper is only available is the kernel was compiled with
3591 * the **CONFIG_BPF_LIRC_MODE2** configuration option set to
3592 * "**y**".
3593 * Return
3594 * 0
3595 *
3596 * u64 bpf_skb_cgroup_id(struct sk_buff *skb)
3597 * Description
3598 * Return the cgroup v2 id of the socket associated with the *skb*.
3599 * This is roughly similar to the **bpf_get_cgroup_classid**\ ()
3600 * helper for cgroup v1 by providing a tag resp. identifier that
3601 * can be matched on or used for map lookups e.g. to implement
3602 * policy. The cgroup v2 id of a given path in the hierarchy is
3603 * exposed in user space through the f_handle API in order to get
3604 * to the same 64-bit id.
3605 *
3606 * This helper can be used on TC egress path, but not on ingress,
3607 * and is available only if the kernel was compiled with the
3608 * **CONFIG_SOCK_CGROUP_DATA** configuration option.
3609 * Return
3610 * The id is returned or 0 in case the id could not be retrieved.
3611 *
3612 * u64 bpf_get_current_cgroup_id(void)
3613 * Description
3614 * Get the current cgroup id based on the cgroup within which
3615 * the current task is running.
3616 * Return
3617 * A 64-bit integer containing the current cgroup id based
3618 * on the cgroup within which the current task is running.
3619 *
3620 * void *bpf_get_local_storage(void *map, u64 flags)
3621 * Description
3622 * Get the pointer to the local storage area.
3623 * The type and the size of the local storage is defined
3624 * by the *map* argument.
3625 * The *flags* meaning is specific for each map type,
3626 * and has to be 0 for cgroup local storage.
3627 *
3628 * Depending on the BPF program type, a local storage area
3629 * can be shared between multiple instances of the BPF program,
3630 * running simultaneously.
3631 *
3632 * A user should care about the synchronization by himself.
3633 * For example, by using the **BPF_ATOMIC** instructions to alter
3634 * the shared data.
3635 * Return
3636 * A pointer to the local storage area.
3637 *
3638 * long bpf_sk_select_reuseport(struct sk_reuseport_md *reuse, struct bpf_map *map, void *key, u64 flags)
3639 * Description
3640 * Select a **SO_REUSEPORT** socket from a
3641 * **BPF_MAP_TYPE_REUSEPORT_SOCKARRAY** *map*.
3642 * It checks the selected socket is matching the incoming
3643 * request in the socket buffer.
3644 * Return
3645 * 0 on success, or a negative error in case of failure.
3646 *
3647 * u64 bpf_skb_ancestor_cgroup_id(struct sk_buff *skb, int ancestor_level)
3648 * Description
3649 * Return id of cgroup v2 that is ancestor of cgroup associated
3650 * with the *skb* at the *ancestor_level*. The root cgroup is at
3651 * *ancestor_level* zero and each step down the hierarchy
3652 * increments the level. If *ancestor_level* == level of cgroup
3653 * associated with *skb*, then return value will be same as that
3654 * of **bpf_skb_cgroup_id**\ ().
3655 *
3656 * The helper is useful to implement policies based on cgroups
3657 * that are upper in hierarchy than immediate cgroup associated
3658 * with *skb*.
3659 *
3660 * The format of returned id and helper limitations are same as in
3661 * **bpf_skb_cgroup_id**\ ().
3662 * Return
3663 * The id is returned or 0 in case the id could not be retrieved.
3664 *
3665 * struct bpf_sock *bpf_sk_lookup_tcp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
3666 * Description
3667 * Look for TCP socket matching *tuple*, optionally in a child
3668 * network namespace *netns*. The return value must be checked,
3669 * and if non-**NULL**, released via **bpf_sk_release**\ ().
3670 *
3671 * The *ctx* should point to the context of the program, such as
3672 * the skb or socket (depending on the hook in use). This is used
3673 * to determine the base network namespace for the lookup.
3674 *
3675 * *tuple_size* must be one of:
3676 *
3677 * **sizeof**\ (*tuple*\ **->ipv4**)
3678 * Look for an IPv4 socket.
3679 * **sizeof**\ (*tuple*\ **->ipv6**)
3680 * Look for an IPv6 socket.
3681 *
3682 * If the *netns* is a negative signed 32-bit integer, then the
3683 * socket lookup table in the netns associated with the *ctx*
3684 * will be used. For the TC hooks, this is the netns of the device
3685 * in the skb. For socket hooks, this is the netns of the socket.
3686 * If *netns* is any other signed 32-bit value greater than or
3687 * equal to zero then it specifies the ID of the netns relative to
3688 * the netns associated with the *ctx*. *netns* values beyond the
3689 * range of 32-bit integers are reserved for future use.
3690 *
3691 * All values for *flags* are reserved for future usage, and must
3692 * be left at zero.
3693 *
3694 * This helper is available only if the kernel was compiled with
3695 * **CONFIG_NET** configuration option.
3696 * Return
3697 * Pointer to **struct bpf_sock**, or **NULL** in case of failure.
3698 * For sockets with reuseport option, the **struct bpf_sock**
3699 * result is from *reuse*\ **->socks**\ [] using the hash of the
3700 * tuple.
3701 *
3702 * struct bpf_sock *bpf_sk_lookup_udp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
3703 * Description
3704 * Look for UDP socket matching *tuple*, optionally in a child
3705 * network namespace *netns*. The return value must be checked,
3706 * and if non-**NULL**, released via **bpf_sk_release**\ ().
3707 *
3708 * The *ctx* should point to the context of the program, such as
3709 * the skb or socket (depending on the hook in use). This is used
3710 * to determine the base network namespace for the lookup.
3711 *
3712 * *tuple_size* must be one of:
3713 *
3714 * **sizeof**\ (*tuple*\ **->ipv4**)
3715 * Look for an IPv4 socket.
3716 * **sizeof**\ (*tuple*\ **->ipv6**)
3717 * Look for an IPv6 socket.
3718 *
3719 * If the *netns* is a negative signed 32-bit integer, then the
3720 * socket lookup table in the netns associated with the *ctx*
3721 * will be used. For the TC hooks, this is the netns of the device
3722 * in the skb. For socket hooks, this is the netns of the socket.
3723 * If *netns* is any other signed 32-bit value greater than or
3724 * equal to zero then it specifies the ID of the netns relative to
3725 * the netns associated with the *ctx*. *netns* values beyond the
3726 * range of 32-bit integers are reserved for future use.
3727 *
3728 * All values for *flags* are reserved for future usage, and must
3729 * be left at zero.
3730 *
3731 * This helper is available only if the kernel was compiled with
3732 * **CONFIG_NET** configuration option.
3733 * Return
3734 * Pointer to **struct bpf_sock**, or **NULL** in case of failure.
3735 * For sockets with reuseport option, the **struct bpf_sock**
3736 * result is from *reuse*\ **->socks**\ [] using the hash of the
3737 * tuple.
3738 *
3739 * long bpf_sk_release(void *sock)
3740 * Description
3741 * Release the reference held by *sock*. *sock* must be a
3742 * non-**NULL** pointer that was returned from
3743 * **bpf_sk_lookup_xxx**\ ().
3744 * Return
3745 * 0 on success, or a negative error in case of failure.
3746 *
3747 * long bpf_map_push_elem(struct bpf_map *map, const void *value, u64 flags)
3748 * Description
3749 * Push an element *value* in *map*. *flags* is one of:
3750 *
3751 * **BPF_EXIST**
3752 * If the queue/stack is full, the oldest element is
3753 * removed to make room for this.
3754 * Return
3755 * 0 on success, or a negative error in case of failure.
3756 *
3757 * long bpf_map_pop_elem(struct bpf_map *map, void *value)
3758 * Description
3759 * Pop an element from *map*.
3760 * Return
3761 * 0 on success, or a negative error in case of failure.
3762 *
3763 * long bpf_map_peek_elem(struct bpf_map *map, void *value)
3764 * Description
3765 * Get an element from *map* without removing it.
3766 * Return
3767 * 0 on success, or a negative error in case of failure.
3768 *
3769 * long bpf_msg_push_data(struct sk_msg_buff *msg, u32 start, u32 len, u64 flags)
3770 * Description
3771 * For socket policies, insert *len* bytes into *msg* at offset
3772 * *start*.
3773 *
3774 * If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a
3775 * *msg* it may want to insert metadata or options into the *msg*.
3776 * This can later be read and used by any of the lower layer BPF
3777 * hooks.
3778 *
3779 * This helper may fail if under memory pressure (a malloc
3780 * fails) in these cases BPF programs will get an appropriate
3781 * error and BPF programs will need to handle them.
3782 * Return
3783 * 0 on success, or a negative error in case of failure.
3784 *
3785 * long bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 len, u64 flags)
3786 * Description
3787 * Will remove *len* bytes from a *msg* starting at byte *start*.
3788 * This may result in **ENOMEM** errors under certain situations if
3789 * an allocation and copy are required due to a full ring buffer.
3790 * However, the helper will try to avoid doing the allocation
3791 * if possible. Other errors can occur if input parameters are
3792 * invalid either due to *start* byte not being valid part of *msg*
3793 * payload and/or *pop* value being to large.
3794 * Return
3795 * 0 on success, or a negative error in case of failure.
3796 *
3797 * long bpf_rc_pointer_rel(void *ctx, s32 rel_x, s32 rel_y)
3798 * Description
3799 * This helper is used in programs implementing IR decoding, to
3800 * report a successfully decoded pointer movement.
3801 *
3802 * The *ctx* should point to the lirc sample as passed into
3803 * the program.
3804 *
3805 * This helper is only available is the kernel was compiled with
3806 * the **CONFIG_BPF_LIRC_MODE2** configuration option set to
3807 * "**y**".
3808 * Return
3809 * 0
3810 *
3811 * long bpf_spin_lock(struct bpf_spin_lock *lock)
3812 * Description
3813 * Acquire a spinlock represented by the pointer *lock*, which is
3814 * stored as part of a value of a map. Taking the lock allows to
3815 * safely update the rest of the fields in that value. The
3816 * spinlock can (and must) later be released with a call to
3817 * **bpf_spin_unlock**\ (\ *lock*\ ).
3818 *
3819 * Spinlocks in BPF programs come with a number of restrictions
3820 * and constraints:
3821 *
3822 * * **bpf_spin_lock** objects are only allowed inside maps of
3823 * types **BPF_MAP_TYPE_HASH** and **BPF_MAP_TYPE_ARRAY** (this
3824 * list could be extended in the future).
3825 * * BTF description of the map is mandatory.
3826 * * The BPF program can take ONE lock at a time, since taking two
3827 * or more could cause dead locks.
3828 * * Only one **struct bpf_spin_lock** is allowed per map element.
3829 * * When the lock is taken, calls (either BPF to BPF or helpers)
3830 * are not allowed.
3831 * * The **BPF_LD_ABS** and **BPF_LD_IND** instructions are not
3832 * allowed inside a spinlock-ed region.
3833 * * The BPF program MUST call **bpf_spin_unlock**\ () to release
3834 * the lock, on all execution paths, before it returns.
3835 * * The BPF program can access **struct bpf_spin_lock** only via
3836 * the **bpf_spin_lock**\ () and **bpf_spin_unlock**\ ()
3837 * helpers. Loading or storing data into the **struct
3838 * bpf_spin_lock** *lock*\ **;** field of a map is not allowed.
3839 * * To use the **bpf_spin_lock**\ () helper, the BTF description
3840 * of the map value must be a struct and have **struct
3841 * bpf_spin_lock** *anyname*\ **;** field at the top level.
3842 * Nested lock inside another struct is not allowed.
3843 * * The **struct bpf_spin_lock** *lock* field in a map value must
3844 * be aligned on a multiple of 4 bytes in that value.
3845 * * Syscall with command **BPF_MAP_LOOKUP_ELEM** does not copy
3846 * the **bpf_spin_lock** field to user space.
3847 * * Syscall with command **BPF_MAP_UPDATE_ELEM**, or update from
3848 * a BPF program, do not update the **bpf_spin_lock** field.
3849 * * **bpf_spin_lock** cannot be on the stack or inside a
3850 * networking packet (it can only be inside of a map values).
3851 * * **bpf_spin_lock** is available to root only.
3852 * * Tracing programs and socket filter programs cannot use
3853 * **bpf_spin_lock**\ () due to insufficient preemption checks
3854 * (but this may change in the future).
3855 * * **bpf_spin_lock** is not allowed in inner maps of map-in-map.
3856 * Return
3857 * 0
3858 *
3859 * long bpf_spin_unlock(struct bpf_spin_lock *lock)
3860 * Description
3861 * Release the *lock* previously locked by a call to
3862 * **bpf_spin_lock**\ (\ *lock*\ ).
3863 * Return
3864 * 0
3865 *
3866 * struct bpf_sock *bpf_sk_fullsock(struct bpf_sock *sk)
3867 * Description
3868 * This helper gets a **struct bpf_sock** pointer such
3869 * that all the fields in this **bpf_sock** can be accessed.
3870 * Return
3871 * A **struct bpf_sock** pointer on success, or **NULL** in
3872 * case of failure.
3873 *
3874 * struct bpf_tcp_sock *bpf_tcp_sock(struct bpf_sock *sk)
3875 * Description
3876 * This helper gets a **struct bpf_tcp_sock** pointer from a
3877 * **struct bpf_sock** pointer.
3878 * Return
3879 * A **struct bpf_tcp_sock** pointer on success, or **NULL** in
3880 * case of failure.
3881 *
3882 * long bpf_skb_ecn_set_ce(struct sk_buff *skb)
3883 * Description
3884 * Set ECN (Explicit Congestion Notification) field of IP header
3885 * to **CE** (Congestion Encountered) if current value is **ECT**
3886 * (ECN Capable Transport). Otherwise, do nothing. Works with IPv6
3887 * and IPv4.
3888 * Return
3889 * 1 if the **CE** flag is set (either by the current helper call
3890 * or because it was already present), 0 if it is not set.
3891 *
3892 * struct bpf_sock *bpf_get_listener_sock(struct bpf_sock *sk)
3893 * Description
3894 * Return a **struct bpf_sock** pointer in **TCP_LISTEN** state.
3895 * **bpf_sk_release**\ () is unnecessary and not allowed.
3896 * Return
3897 * A **struct bpf_sock** pointer on success, or **NULL** in
3898 * case of failure.
3899 *
3900 * struct bpf_sock *bpf_skc_lookup_tcp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
3901 * Description
3902 * Look for TCP socket matching *tuple*, optionally in a child
3903 * network namespace *netns*. The return value must be checked,
3904 * and if non-**NULL**, released via **bpf_sk_release**\ ().
3905 *
3906 * This function is identical to **bpf_sk_lookup_tcp**\ (), except
3907 * that it also returns timewait or request sockets. Use
3908 * **bpf_sk_fullsock**\ () or **bpf_tcp_sock**\ () to access the
3909 * full structure.
3910 *
3911 * This helper is available only if the kernel was compiled with
3912 * **CONFIG_NET** configuration option.
3913 * Return
3914 * Pointer to **struct bpf_sock**, or **NULL** in case of failure.
3915 * For sockets with reuseport option, the **struct bpf_sock**
3916 * result is from *reuse*\ **->socks**\ [] using the hash of the
3917 * tuple.
3918 *
3919 * long bpf_tcp_check_syncookie(void *sk, void *iph, u32 iph_len, struct tcphdr *th, u32 th_len)
3920 * Description
3921 * Check whether *iph* and *th* contain a valid SYN cookie ACK for
3922 * the listening socket in *sk*.
3923 *
3924 * *iph* points to the start of the IPv4 or IPv6 header, while
3925 * *iph_len* contains **sizeof**\ (**struct iphdr**) or
3926 * **sizeof**\ (**struct ipv6hdr**).
3927 *
3928 * *th* points to the start of the TCP header, while *th_len*
3929 * contains the length of the TCP header (at least
3930 * **sizeof**\ (**struct tcphdr**)).
3931 * Return
3932 * 0 if *iph* and *th* are a valid SYN cookie ACK, or a negative
3933 * error otherwise.
3934 *
3935 * long bpf_sysctl_get_name(struct bpf_sysctl *ctx, char *buf, size_t buf_len, u64 flags)
3936 * Description
3937 * Get name of sysctl in /proc/sys/ and copy it into provided by
3938 * program buffer *buf* of size *buf_len*.
3939 *
3940 * The buffer is always NUL terminated, unless it's zero-sized.
3941 *
3942 * If *flags* is zero, full name (e.g. "net/ipv4/tcp_mem") is
3943 * copied. Use **BPF_F_SYSCTL_BASE_NAME** flag to copy base name
3944 * only (e.g. "tcp_mem").
3945 * Return
3946 * Number of character copied (not including the trailing NUL).
3947 *
3948 * **-E2BIG** if the buffer wasn't big enough (*buf* will contain
3949 * truncated name in this case).
3950 *
3951 * long bpf_sysctl_get_current_value(struct bpf_sysctl *ctx, char *buf, size_t buf_len)
3952 * Description
3953 * Get current value of sysctl as it is presented in /proc/sys
3954 * (incl. newline, etc), and copy it as a string into provided
3955 * by program buffer *buf* of size *buf_len*.
3956 *
3957 * The whole value is copied, no matter what file position user
3958 * space issued e.g. sys_read at.
3959 *
3960 * The buffer is always NUL terminated, unless it's zero-sized.
3961 * Return
3962 * Number of character copied (not including the trailing NUL).
3963 *
3964 * **-E2BIG** if the buffer wasn't big enough (*buf* will contain
3965 * truncated name in this case).
3966 *
3967 * **-EINVAL** if current value was unavailable, e.g. because
3968 * sysctl is uninitialized and read returns -EIO for it.
3969 *
3970 * long bpf_sysctl_get_new_value(struct bpf_sysctl *ctx, char *buf, size_t buf_len)
3971 * Description
3972 * Get new value being written by user space to sysctl (before
3973 * the actual write happens) and copy it as a string into
3974 * provided by program buffer *buf* of size *buf_len*.
3975 *
3976 * User space may write new value at file position > 0.
3977 *
3978 * The buffer is always NUL terminated, unless it's zero-sized.
3979 * Return
3980 * Number of character copied (not including the trailing NUL).
3981 *
3982 * **-E2BIG** if the buffer wasn't big enough (*buf* will contain
3983 * truncated name in this case).
3984 *
3985 * **-EINVAL** if sysctl is being read.
3986 *
3987 * long bpf_sysctl_set_new_value(struct bpf_sysctl *ctx, const char *buf, size_t buf_len)
3988 * Description
3989 * Override new value being written by user space to sysctl with
3990 * value provided by program in buffer *buf* of size *buf_len*.
3991 *
3992 * *buf* should contain a string in same form as provided by user
3993 * space on sysctl write.
3994 *
3995 * User space may write new value at file position > 0. To override
3996 * the whole sysctl value file position should be set to zero.
3997 * Return
3998 * 0 on success.
3999 *
4000 * **-E2BIG** if the *buf_len* is too big.
4001 *
4002 * **-EINVAL** if sysctl is being read.
4003 *
4004 * long bpf_strtol(const char *buf, size_t buf_len, u64 flags, long *res)
4005 * Description
4006 * Convert the initial part of the string from buffer *buf* of
4007 * size *buf_len* to a long integer according to the given base
4008 * and save the result in *res*.
4009 *
4010 * The string may begin with an arbitrary amount of white space
4011 * (as determined by **isspace**\ (3)) followed by a single
4012 * optional '**-**' sign.
4013 *
4014 * Five least significant bits of *flags* encode base, other bits
4015 * are currently unused.
4016 *
4017 * Base must be either 8, 10, 16 or 0 to detect it automatically
4018 * similar to user space **strtol**\ (3).
4019 * Return
4020 * Number of characters consumed on success. Must be positive but
4021 * no more than *buf_len*.
4022 *
4023 * **-EINVAL** if no valid digits were found or unsupported base
4024 * was provided.
4025 *
4026 * **-ERANGE** if resulting value was out of range.
4027 *
4028 * long bpf_strtoul(const char *buf, size_t buf_len, u64 flags, unsigned long *res)
4029 * Description
4030 * Convert the initial part of the string from buffer *buf* of
4031 * size *buf_len* to an unsigned long integer according to the
4032 * given base and save the result in *res*.
4033 *
4034 * The string may begin with an arbitrary amount of white space
4035 * (as determined by **isspace**\ (3)).
4036 *
4037 * Five least significant bits of *flags* encode base, other bits
4038 * are currently unused.
4039 *
4040 * Base must be either 8, 10, 16 or 0 to detect it automatically
4041 * similar to user space **strtoul**\ (3).
4042 * Return
4043 * Number of characters consumed on success. Must be positive but
4044 * no more than *buf_len*.
4045 *
4046 * **-EINVAL** if no valid digits were found or unsupported base
4047 * was provided.
4048 *
4049 * **-ERANGE** if resulting value was out of range.
4050 *
4051 * void *bpf_sk_storage_get(struct bpf_map *map, void *sk, void *value, u64 flags)
4052 * Description
4053 * Get a bpf-local-storage from a *sk*.
4054 *
4055 * Logically, it could be thought of getting the value from
4056 * a *map* with *sk* as the **key**. From this
4057 * perspective, the usage is not much different from
4058 * **bpf_map_lookup_elem**\ (*map*, **&**\ *sk*) except this
4059 * helper enforces the key must be a full socket and the map must
4060 * be a **BPF_MAP_TYPE_SK_STORAGE** also.
4061 *
4062 * Underneath, the value is stored locally at *sk* instead of
4063 * the *map*. The *map* is used as the bpf-local-storage
4064 * "type". The bpf-local-storage "type" (i.e. the *map*) is
4065 * searched against all bpf-local-storages residing at *sk*.
4066 *
4067 * *sk* is a kernel **struct sock** pointer for LSM program.
4068 * *sk* is a **struct bpf_sock** pointer for other program types.
4069 *
4070 * An optional *flags* (**BPF_SK_STORAGE_GET_F_CREATE**) can be
4071 * used such that a new bpf-local-storage will be
4072 * created if one does not exist. *value* can be used
4073 * together with **BPF_SK_STORAGE_GET_F_CREATE** to specify
4074 * the initial value of a bpf-local-storage. If *value* is
4075 * **NULL**, the new bpf-local-storage will be zero initialized.
4076 * Return
4077 * A bpf-local-storage pointer is returned on success.
4078 *
4079 * **NULL** if not found or there was an error in adding
4080 * a new bpf-local-storage.
4081 *
4082 * long bpf_sk_storage_delete(struct bpf_map *map, void *sk)
4083 * Description
4084 * Delete a bpf-local-storage from a *sk*.
4085 * Return
4086 * 0 on success.
4087 *
4088 * **-ENOENT** if the bpf-local-storage cannot be found.
4089 * **-EINVAL** if sk is not a fullsock (e.g. a request_sock).
4090 *
4091 * long bpf_send_signal(u32 sig)
4092 * Description
4093 * Send signal *sig* to the process of the current task.
4094 * The signal may be delivered to any of this process's threads.
4095 * Return
4096 * 0 on success or successfully queued.
4097 *
4098 * **-EBUSY** if work queue under nmi is full.
4099 *
4100 * **-EINVAL** if *sig* is invalid.
4101 *
4102 * **-EPERM** if no permission to send the *sig*.
4103 *
4104 * **-EAGAIN** if bpf program can try again.
4105 *
4106 * s64 bpf_tcp_gen_syncookie(void *sk, void *iph, u32 iph_len, struct tcphdr *th, u32 th_len)
4107 * Description
4108 * Try to issue a SYN cookie for the packet with corresponding
4109 * IP/TCP headers, *iph* and *th*, on the listening socket in *sk*.
4110 *
4111 * *iph* points to the start of the IPv4 or IPv6 header, while
4112 * *iph_len* contains **sizeof**\ (**struct iphdr**) or
4113 * **sizeof**\ (**struct ipv6hdr**).
4114 *
4115 * *th* points to the start of the TCP header, while *th_len*
4116 * contains the length of the TCP header with options (at least
4117 * **sizeof**\ (**struct tcphdr**)).
4118 * Return
4119 * On success, lower 32 bits hold the generated SYN cookie in
4120 * followed by 16 bits which hold the MSS value for that cookie,
4121 * and the top 16 bits are unused.
4122 *
4123 * On failure, the returned value is one of the following:
4124 *
4125 * **-EINVAL** SYN cookie cannot be issued due to error
4126 *
4127 * **-ENOENT** SYN cookie should not be issued (no SYN flood)
4128 *
4129 * **-EOPNOTSUPP** kernel configuration does not enable SYN cookies
4130 *
4131 * **-EPROTONOSUPPORT** IP packet version is not 4 or 6
4132 *
4133 * long bpf_skb_output(void *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
4134 * Description
4135 * Write raw *data* blob into a special BPF perf event held by
4136 * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf
4137 * event must have the following attributes: **PERF_SAMPLE_RAW**
4138 * as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and
4139 * **PERF_COUNT_SW_BPF_OUTPUT** as **config**.
4140 *
4141 * The *flags* are used to indicate the index in *map* for which
4142 * the value must be put, masked with **BPF_F_INDEX_MASK**.
4143 * Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU**
4144 * to indicate that the index of the current CPU core should be
4145 * used.
4146 *
4147 * The value to write, of *size*, is passed through eBPF stack and
4148 * pointed by *data*.
4149 *
4150 * *ctx* is a pointer to in-kernel struct sk_buff.
4151 *
4152 * This helper is similar to **bpf_perf_event_output**\ () but
4153 * restricted to raw_tracepoint bpf programs.
4154 * Return
4155 * 0 on success, or a negative error in case of failure.
4156 *
4157 * long bpf_probe_read_user(void *dst, u32 size, const void *unsafe_ptr)
4158 * Description
4159 * Safely attempt to read *size* bytes from user space address
4160 * *unsafe_ptr* and store the data in *dst*.
4161 * Return
4162 * 0 on success, or a negative error in case of failure.
4163 *
4164 * long bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr)
4165 * Description
4166 * Safely attempt to read *size* bytes from kernel space address
4167 * *unsafe_ptr* and store the data in *dst*.
4168 * Return
4169 * 0 on success, or a negative error in case of failure.
4170 *
4171 * long bpf_probe_read_user_str(void *dst, u32 size, const void *unsafe_ptr)
4172 * Description
4173 * Copy a NUL terminated string from an unsafe user address
4174 * *unsafe_ptr* to *dst*. The *size* should include the
4175 * terminating NUL byte. In case the string length is smaller than
4176 * *size*, the target is not padded with further NUL bytes. If the
4177 * string length is larger than *size*, just *size*-1 bytes are
4178 * copied and the last byte is set to NUL.
4179 *
4180 * On success, returns the number of bytes that were written,
4181 * including the terminal NUL. This makes this helper useful in
4182 * tracing programs for reading strings, and more importantly to
4183 * get its length at runtime. See the following snippet:
4184 *
4185 * ::
4186 *
4187 * SEC("kprobe/sys_open")
4188 * void bpf_sys_open(struct pt_regs *ctx)
4189 * {
4190 * char buf[PATHLEN]; // PATHLEN is defined to 256
4191 * int res = bpf_probe_read_user_str(buf, sizeof(buf),
4192 * ctx->di);
4193 *
4194 * // Consume buf, for example push it to
4195 * // userspace via bpf_perf_event_output(); we
4196 * // can use res (the string length) as event
4197 * // size, after checking its boundaries.
4198 * }
4199 *
4200 * In comparison, using **bpf_probe_read_user**\ () helper here
4201 * instead to read the string would require to estimate the length
4202 * at compile time, and would often result in copying more memory
4203 * than necessary.
4204 *
4205 * Another useful use case is when parsing individual process
4206 * arguments or individual environment variables navigating
4207 * *current*\ **->mm->arg_start** and *current*\
4208 * **->mm->env_start**: using this helper and the return value,
4209 * one can quickly iterate at the right offset of the memory area.
4210 * Return
4211 * On success, the strictly positive length of the output string,
4212 * including the trailing NUL character. On error, a negative
4213 * value.
4214 *
4215 * long bpf_probe_read_kernel_str(void *dst, u32 size, const void *unsafe_ptr)
4216 * Description
4217 * Copy a NUL terminated string from an unsafe kernel address *unsafe_ptr*
4218 * to *dst*. Same semantics as with **bpf_probe_read_user_str**\ () apply.
4219 * Return
4220 * On success, the strictly positive length of the string, including
4221 * the trailing NUL character. On error, a negative value.
4222 *
4223 * long bpf_tcp_send_ack(void *tp, u32 rcv_nxt)
4224 * Description
4225 * Send out a tcp-ack. *tp* is the in-kernel struct **tcp_sock**.
4226 * *rcv_nxt* is the ack_seq to be sent out.
4227 * Return
4228 * 0 on success, or a negative error in case of failure.
4229 *
4230 * long bpf_send_signal_thread(u32 sig)
4231 * Description
4232 * Send signal *sig* to the thread corresponding to the current task.
4233 * Return
4234 * 0 on success or successfully queued.
4235 *
4236 * **-EBUSY** if work queue under nmi is full.
4237 *
4238 * **-EINVAL** if *sig* is invalid.
4239 *
4240 * **-EPERM** if no permission to send the *sig*.
4241 *
4242 * **-EAGAIN** if bpf program can try again.
4243 *
4244 * u64 bpf_jiffies64(void)
4245 * Description
4246 * Obtain the 64bit jiffies
4247 * Return
4248 * The 64 bit jiffies
4249 *
4250 * long bpf_read_branch_records(struct bpf_perf_event_data *ctx, void *buf, u32 size, u64 flags)
4251 * Description
4252 * For an eBPF program attached to a perf event, retrieve the
4253 * branch records (**struct perf_branch_entry**) associated to *ctx*
4254 * and store it in the buffer pointed by *buf* up to size
4255 * *size* bytes.
4256 * Return
4257 * On success, number of bytes written to *buf*. On error, a
4258 * negative value.
4259 *
4260 * The *flags* can be set to **BPF_F_GET_BRANCH_RECORDS_SIZE** to
4261 * instead return the number of bytes required to store all the
4262 * branch entries. If this flag is set, *buf* may be NULL.
4263 *
4264 * **-EINVAL** if arguments invalid or **size** not a multiple
4265 * of **sizeof**\ (**struct perf_branch_entry**\ ).
4266 *
4267 * **-ENOENT** if architecture does not support branch records.
4268 *
4269 * long bpf_get_ns_current_pid_tgid(u64 dev, u64 ino, struct bpf_pidns_info *nsdata, u32 size)
4270 * Description
4271 * Returns 0 on success, values for *pid* and *tgid* as seen from the current
4272 * *namespace* will be returned in *nsdata*.
4273 * Return
4274 * 0 on success, or one of the following in case of failure:
4275 *
4276 * **-EINVAL** if dev and inum supplied don't match dev_t and inode number
4277 * with nsfs of current task, or if dev conversion to dev_t lost high bits.
4278 *
4279 * **-ENOENT** if pidns does not exists for the current task.
4280 *
4281 * long bpf_xdp_output(void *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
4282 * Description
4283 * Write raw *data* blob into a special BPF perf event held by
4284 * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf
4285 * event must have the following attributes: **PERF_SAMPLE_RAW**
4286 * as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and
4287 * **PERF_COUNT_SW_BPF_OUTPUT** as **config**.
4288 *
4289 * The *flags* are used to indicate the index in *map* for which
4290 * the value must be put, masked with **BPF_F_INDEX_MASK**.
4291 * Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU**
4292 * to indicate that the index of the current CPU core should be
4293 * used.
4294 *
4295 * The value to write, of *size*, is passed through eBPF stack and
4296 * pointed by *data*.
4297 *
4298 * *ctx* is a pointer to in-kernel struct xdp_buff.
4299 *
4300 * This helper is similar to **bpf_perf_eventoutput**\ () but
4301 * restricted to raw_tracepoint bpf programs.
4302 * Return
4303 * 0 on success, or a negative error in case of failure.
4304 *
4305 * u64 bpf_get_netns_cookie(void *ctx)
4306 * Description
4307 * Retrieve the cookie (generated by the kernel) of the network
4308 * namespace the input *ctx* is associated with. The network
4309 * namespace cookie remains stable for its lifetime and provides
4310 * a global identifier that can be assumed unique. If *ctx* is
4311 * NULL, then the helper returns the cookie for the initial
4312 * network namespace. The cookie itself is very similar to that
4313 * of **bpf_get_socket_cookie**\ () helper, but for network
4314 * namespaces instead of sockets.
4315 * Return
4316 * A 8-byte long opaque number.
4317 *
4318 * u64 bpf_get_current_ancestor_cgroup_id(int ancestor_level)
4319 * Description
4320 * Return id of cgroup v2 that is ancestor of the cgroup associated
4321 * with the current task at the *ancestor_level*. The root cgroup
4322 * is at *ancestor_level* zero and each step down the hierarchy
4323 * increments the level. If *ancestor_level* == level of cgroup
4324 * associated with the current task, then return value will be the
4325 * same as that of **bpf_get_current_cgroup_id**\ ().
4326 *
4327 * The helper is useful to implement policies based on cgroups
4328 * that are upper in hierarchy than immediate cgroup associated
4329 * with the current task.
4330 *
4331 * The format of returned id and helper limitations are same as in
4332 * **bpf_get_current_cgroup_id**\ ().
4333 * Return
4334 * The id is returned or 0 in case the id could not be retrieved.
4335 *
4336 * long bpf_sk_assign(struct sk_buff *skb, void *sk, u64 flags)
4337 * Description
4338 * Helper is overloaded depending on BPF program type. This
4339 * description applies to **BPF_PROG_TYPE_SCHED_CLS** and
4340 * **BPF_PROG_TYPE_SCHED_ACT** programs.
4341 *
4342 * Assign the *sk* to the *skb*. When combined with appropriate
4343 * routing configuration to receive the packet towards the socket,
4344 * will cause *skb* to be delivered to the specified socket.
4345 * Subsequent redirection of *skb* via **bpf_redirect**\ (),
4346 * **bpf_clone_redirect**\ () or other methods outside of BPF may
4347 * interfere with successful delivery to the socket.
4348 *
4349 * This operation is only valid from TC ingress path.
4350 *
4351 * The *flags* argument must be zero.
4352 * Return
4353 * 0 on success, or a negative error in case of failure:
4354 *
4355 * **-EINVAL** if specified *flags* are not supported.
4356 *
4357 * **-ENOENT** if the socket is unavailable for assignment.
4358 *
4359 * **-ENETUNREACH** if the socket is unreachable (wrong netns).
4360 *
4361 * **-EOPNOTSUPP** if the operation is not supported, for example
4362 * a call from outside of TC ingress.
4363 *
4364 * long bpf_sk_assign(struct bpf_sk_lookup *ctx, struct bpf_sock *sk, u64 flags)
4365 * Description
4366 * Helper is overloaded depending on BPF program type. This
4367 * description applies to **BPF_PROG_TYPE_SK_LOOKUP** programs.
4368 *
4369 * Select the *sk* as a result of a socket lookup.
4370 *
4371 * For the operation to succeed passed socket must be compatible
4372 * with the packet description provided by the *ctx* object.
4373 *
4374 * L4 protocol (**IPPROTO_TCP** or **IPPROTO_UDP**) must
4375 * be an exact match. While IP family (**AF_INET** or
4376 * **AF_INET6**) must be compatible, that is IPv6 sockets
4377 * that are not v6-only can be selected for IPv4 packets.
4378 *
4379 * Only TCP listeners and UDP unconnected sockets can be
4380 * selected. *sk* can also be NULL to reset any previous
4381 * selection.
4382 *
4383 * *flags* argument can combination of following values:
4384 *
4385 * * **BPF_SK_LOOKUP_F_REPLACE** to override the previous
4386 * socket selection, potentially done by a BPF program
4387 * that ran before us.
4388 *
4389 * * **BPF_SK_LOOKUP_F_NO_REUSEPORT** to skip
4390 * load-balancing within reuseport group for the socket
4391 * being selected.
4392 *
4393 * On success *ctx->sk* will point to the selected socket.
4394 *
4395 * Return
4396 * 0 on success, or a negative errno in case of failure.
4397 *
4398 * * **-EAFNOSUPPORT** if socket family (*sk->family*) is
4399 * not compatible with packet family (*ctx->family*).
4400 *
4401 * * **-EEXIST** if socket has been already selected,
4402 * potentially by another program, and
4403 * **BPF_SK_LOOKUP_F_REPLACE** flag was not specified.
4404 *
4405 * * **-EINVAL** if unsupported flags were specified.
4406 *
4407 * * **-EPROTOTYPE** if socket L4 protocol
4408 * (*sk->protocol*) doesn't match packet protocol
4409 * (*ctx->protocol*).
4410 *
4411 * * **-ESOCKTNOSUPPORT** if socket is not in allowed
4412 * state (TCP listening or UDP unconnected).
4413 *
4414 * u64 bpf_ktime_get_boot_ns(void)
4415 * Description
4416 * Return the time elapsed since system boot, in nanoseconds.
4417 * Does include the time the system was suspended.
4418 * See: **clock_gettime**\ (**CLOCK_BOOTTIME**)
4419 * Return
4420 * Current *ktime*.
4421 *
4422 * long bpf_seq_printf(struct seq_file *m, const char *fmt, u32 fmt_size, const void *data, u32 data_len)
4423 * Description
4424 * **bpf_seq_printf**\ () uses seq_file **seq_printf**\ () to print
4425 * out the format string.
4426 * The *m* represents the seq_file. The *fmt* and *fmt_size* are for
4427 * the format string itself. The *data* and *data_len* are format string
4428 * arguments. The *data* are a **u64** array and corresponding format string
4429 * values are stored in the array. For strings and pointers where pointees
4430 * are accessed, only the pointer values are stored in the *data* array.
4431 * The *data_len* is the size of *data* in bytes - must be a multiple of 8.
4432 *
4433 * Formats **%s**, **%p{i,I}{4,6}** requires to read kernel memory.
4434 * Reading kernel memory may fail due to either invalid address or
4435 * valid address but requiring a major memory fault. If reading kernel memory
4436 * fails, the string for **%s** will be an empty string, and the ip
4437 * address for **%p{i,I}{4,6}** will be 0. Not returning error to
4438 * bpf program is consistent with what **bpf_trace_printk**\ () does for now.
4439 * Return
4440 * 0 on success, or a negative error in case of failure:
4441 *
4442 * **-EBUSY** if per-CPU memory copy buffer is busy, can try again
4443 * by returning 1 from bpf program.
4444 *
4445 * **-EINVAL** if arguments are invalid, or if *fmt* is invalid/unsupported.
4446 *
4447 * **-E2BIG** if *fmt* contains too many format specifiers.
4448 *
4449 * **-EOVERFLOW** if an overflow happened: The same object will be tried again.
4450 *
4451 * long bpf_seq_write(struct seq_file *m, const void *data, u32 len)
4452 * Description
4453 * **bpf_seq_write**\ () uses seq_file **seq_write**\ () to write the data.
4454 * The *m* represents the seq_file. The *data* and *len* represent the
4455 * data to write in bytes.
4456 * Return
4457 * 0 on success, or a negative error in case of failure:
4458 *
4459 * **-EOVERFLOW** if an overflow happened: The same object will be tried again.
4460 *
4461 * u64 bpf_sk_cgroup_id(void *sk)
4462 * Description
4463 * Return the cgroup v2 id of the socket *sk*.
4464 *
4465 * *sk* must be a non-**NULL** pointer to a socket, e.g. one
4466 * returned from **bpf_sk_lookup_xxx**\ (),
4467 * **bpf_sk_fullsock**\ (), etc. The format of returned id is
4468 * same as in **bpf_skb_cgroup_id**\ ().
4469 *
4470 * This helper is available only if the kernel was compiled with
4471 * the **CONFIG_SOCK_CGROUP_DATA** configuration option.
4472 * Return
4473 * The id is returned or 0 in case the id could not be retrieved.
4474 *
4475 * u64 bpf_sk_ancestor_cgroup_id(void *sk, int ancestor_level)
4476 * Description
4477 * Return id of cgroup v2 that is ancestor of cgroup associated
4478 * with the *sk* at the *ancestor_level*. The root cgroup is at
4479 * *ancestor_level* zero and each step down the hierarchy
4480 * increments the level. If *ancestor_level* == level of cgroup
4481 * associated with *sk*, then return value will be same as that
4482 * of **bpf_sk_cgroup_id**\ ().
4483 *
4484 * The helper is useful to implement policies based on cgroups
4485 * that are upper in hierarchy than immediate cgroup associated
4486 * with *sk*.
4487 *
4488 * The format of returned id and helper limitations are same as in
4489 * **bpf_sk_cgroup_id**\ ().
4490 * Return
4491 * The id is returned or 0 in case the id could not be retrieved.
4492 *
4493 * long bpf_ringbuf_output(void *ringbuf, void *data, u64 size, u64 flags)
4494 * Description
4495 * Copy *size* bytes from *data* into a ring buffer *ringbuf*.
4496 * If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
4497 * of new data availability is sent.
4498 * If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
4499 * of new data availability is sent unconditionally.
4500 * If **0** is specified in *flags*, an adaptive notification
4501 * of new data availability is sent.
4502 *
4503 * An adaptive notification is a notification sent whenever the user-space
4504 * process has caught up and consumed all available payloads. In case the user-space
4505 * process is still processing a previous payload, then no notification is needed
4506 * as it will process the newly added payload automatically.
4507 * Return
4508 * 0 on success, or a negative error in case of failure.
4509 *
4510 * void *bpf_ringbuf_reserve(void *ringbuf, u64 size, u64 flags)
4511 * Description
4512 * Reserve *size* bytes of payload in a ring buffer *ringbuf*.
4513 * *flags* must be 0.
4514 * Return
4515 * Valid pointer with *size* bytes of memory available; NULL,
4516 * otherwise.
4517 *
4518 * void bpf_ringbuf_submit(void *data, u64 flags)
4519 * Description
4520 * Submit reserved ring buffer sample, pointed to by *data*.
4521 * If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
4522 * of new data availability is sent.
4523 * If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
4524 * of new data availability is sent unconditionally.
4525 * If **0** is specified in *flags*, an adaptive notification
4526 * of new data availability is sent.
4527 *
4528 * See 'bpf_ringbuf_output()' for the definition of adaptive notification.
4529 * Return
4530 * Nothing. Always succeeds.
4531 *
4532 * void bpf_ringbuf_discard(void *data, u64 flags)
4533 * Description
4534 * Discard reserved ring buffer sample, pointed to by *data*.
4535 * If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
4536 * of new data availability is sent.
4537 * If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
4538 * of new data availability is sent unconditionally.
4539 * If **0** is specified in *flags*, an adaptive notification
4540 * of new data availability is sent.
4541 *
4542 * See 'bpf_ringbuf_output()' for the definition of adaptive notification.
4543 * Return
4544 * Nothing. Always succeeds.
4545 *
4546 * u64 bpf_ringbuf_query(void *ringbuf, u64 flags)
4547 * Description
4548 * Query various characteristics of provided ring buffer. What
4549 * exactly is queries is determined by *flags*:
4550 *
4551 * * **BPF_RB_AVAIL_DATA**: Amount of data not yet consumed.
4552 * * **BPF_RB_RING_SIZE**: The size of ring buffer.
4553 * * **BPF_RB_CONS_POS**: Consumer position (can wrap around).
4554 * * **BPF_RB_PROD_POS**: Producer(s) position (can wrap around).
4555 *
4556 * Data returned is just a momentary snapshot of actual values
4557 * and could be inaccurate, so this facility should be used to
4558 * power heuristics and for reporting, not to make 100% correct
4559 * calculation.
4560 * Return
4561 * Requested value, or 0, if *flags* are not recognized.
4562 *
4563 * long bpf_csum_level(struct sk_buff *skb, u64 level)
4564 * Description
4565 * Change the skbs checksum level by one layer up or down, or
4566 * reset it entirely to none in order to have the stack perform
4567 * checksum validation. The level is applicable to the following
4568 * protocols: TCP, UDP, GRE, SCTP, FCOE. For example, a decap of
4569 * | ETH | IP | UDP | GUE | IP | TCP | into | ETH | IP | TCP |
4570 * through **bpf_skb_adjust_room**\ () helper with passing in
4571 * **BPF_F_ADJ_ROOM_NO_CSUM_RESET** flag would require one call
4572 * to **bpf_csum_level**\ () with **BPF_CSUM_LEVEL_DEC** since
4573 * the UDP header is removed. Similarly, an encap of the latter
4574 * into the former could be accompanied by a helper call to
4575 * **bpf_csum_level**\ () with **BPF_CSUM_LEVEL_INC** if the
4576 * skb is still intended to be processed in higher layers of the
4577 * stack instead of just egressing at tc.
4578 *
4579 * There are three supported level settings at this time:
4580 *
4581 * * **BPF_CSUM_LEVEL_INC**: Increases skb->csum_level for skbs
4582 * with CHECKSUM_UNNECESSARY.
4583 * * **BPF_CSUM_LEVEL_DEC**: Decreases skb->csum_level for skbs
4584 * with CHECKSUM_UNNECESSARY.
4585 * * **BPF_CSUM_LEVEL_RESET**: Resets skb->csum_level to 0 and
4586 * sets CHECKSUM_NONE to force checksum validation by the stack.
4587 * * **BPF_CSUM_LEVEL_QUERY**: No-op, returns the current
4588 * skb->csum_level.
4589 * Return
4590 * 0 on success, or a negative error in case of failure. In the
4591 * case of **BPF_CSUM_LEVEL_QUERY**, the current skb->csum_level
4592 * is returned or the error code -EACCES in case the skb is not
4593 * subject to CHECKSUM_UNNECESSARY.
4594 *
4595 * struct tcp6_sock *bpf_skc_to_tcp6_sock(void *sk)
4596 * Description
4597 * Dynamically cast a *sk* pointer to a *tcp6_sock* pointer.
4598 * Return
4599 * *sk* if casting is valid, or **NULL** otherwise.
4600 *
4601 * struct tcp_sock *bpf_skc_to_tcp_sock(void *sk)
4602 * Description
4603 * Dynamically cast a *sk* pointer to a *tcp_sock* pointer.
4604 * Return
4605 * *sk* if casting is valid, or **NULL** otherwise.
4606 *
4607 * struct tcp_timewait_sock *bpf_skc_to_tcp_timewait_sock(void *sk)
4608 * Description
4609 * Dynamically cast a *sk* pointer to a *tcp_timewait_sock* pointer.
4610 * Return
4611 * *sk* if casting is valid, or **NULL** otherwise.
4612 *
4613 * struct tcp_request_sock *bpf_skc_to_tcp_request_sock(void *sk)
4614 * Description
4615 * Dynamically cast a *sk* pointer to a *tcp_request_sock* pointer.
4616 * Return
4617 * *sk* if casting is valid, or **NULL** otherwise.
4618 *
4619 * struct udp6_sock *bpf_skc_to_udp6_sock(void *sk)
4620 * Description
4621 * Dynamically cast a *sk* pointer to a *udp6_sock* pointer.
4622 * Return
4623 * *sk* if casting is valid, or **NULL** otherwise.
4624 *
4625 * long bpf_get_task_stack(struct task_struct *task, void *buf, u32 size, u64 flags)
4626 * Description
4627 * Return a user or a kernel stack in bpf program provided buffer.
4628 * Note: the user stack will only be populated if the *task* is
4629 * the current task; all other tasks will return -EOPNOTSUPP.
4630 * To achieve this, the helper needs *task*, which is a valid
4631 * pointer to **struct task_struct**. To store the stacktrace, the
4632 * bpf program provides *buf* with a nonnegative *size*.
4633 *
4634 * The last argument, *flags*, holds the number of stack frames to
4635 * skip (from 0 to 255), masked with
4636 * **BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set
4637 * the following flags:
4638 *
4639 * **BPF_F_USER_STACK**
4640 * Collect a user space stack instead of a kernel stack.
4641 * The *task* must be the current task.
4642 * **BPF_F_USER_BUILD_ID**
4643 * Collect buildid+offset instead of ips for user stack,
4644 * only valid if **BPF_F_USER_STACK** is also specified.
4645 *
4646 * **bpf_get_task_stack**\ () can collect up to
4647 * **PERF_MAX_STACK_DEPTH** both kernel and user frames, subject
4648 * to sufficient large buffer size. Note that
4649 * this limit can be controlled with the **sysctl** program, and
4650 * that it should be manually increased in order to profile long
4651 * user stacks (such as stacks for Java programs). To do so, use:
4652 *
4653 * ::
4654 *
4655 * # sysctl kernel.perf_event_max_stack=<new value>
4656 * Return
4657 * The non-negative copied *buf* length equal to or less than
4658 * *size* on success, or a negative error in case of failure.
4659 *
4660 * long bpf_load_hdr_opt(struct bpf_sock_ops *skops, void *searchby_res, u32 len, u64 flags)
4661 * Description
4662 * Load header option. Support reading a particular TCP header
4663 * option for bpf program (**BPF_PROG_TYPE_SOCK_OPS**).
4664 *
4665 * If *flags* is 0, it will search the option from the
4666 * *skops*\ **->skb_data**. The comment in **struct bpf_sock_ops**
4667 * has details on what skb_data contains under different
4668 * *skops*\ **->op**.
4669 *
4670 * The first byte of the *searchby_res* specifies the
4671 * kind that it wants to search.
4672 *
4673 * If the searching kind is an experimental kind
4674 * (i.e. 253 or 254 according to RFC6994). It also
4675 * needs to specify the "magic" which is either
4676 * 2 bytes or 4 bytes. It then also needs to
4677 * specify the size of the magic by using
4678 * the 2nd byte which is "kind-length" of a TCP
4679 * header option and the "kind-length" also
4680 * includes the first 2 bytes "kind" and "kind-length"
4681 * itself as a normal TCP header option also does.
4682 *
4683 * For example, to search experimental kind 254 with
4684 * 2 byte magic 0xeB9F, the searchby_res should be
4685 * [ 254, 4, 0xeB, 0x9F, 0, 0, .... 0 ].
4686 *
4687 * To search for the standard window scale option (3),
4688 * the *searchby_res* should be [ 3, 0, 0, .... 0 ].
4689 * Note, kind-length must be 0 for regular option.
4690 *
4691 * Searching for No-Op (0) and End-of-Option-List (1) are
4692 * not supported.
4693 *
4694 * *len* must be at least 2 bytes which is the minimal size
4695 * of a header option.
4696 *
4697 * Supported flags:
4698 *
4699 * * **BPF_LOAD_HDR_OPT_TCP_SYN** to search from the
4700 * saved_syn packet or the just-received syn packet.
4701 *
4702 * Return
4703 * > 0 when found, the header option is copied to *searchby_res*.
4704 * The return value is the total length copied. On failure, a
4705 * negative error code is returned:
4706 *
4707 * **-EINVAL** if a parameter is invalid.
4708 *
4709 * **-ENOMSG** if the option is not found.
4710 *
4711 * **-ENOENT** if no syn packet is available when
4712 * **BPF_LOAD_HDR_OPT_TCP_SYN** is used.
4713 *
4714 * **-ENOSPC** if there is not enough space. Only *len* number of
4715 * bytes are copied.
4716 *
4717 * **-EFAULT** on failure to parse the header options in the
4718 * packet.
4719 *
4720 * **-EPERM** if the helper cannot be used under the current
4721 * *skops*\ **->op**.
4722 *
4723 * long bpf_store_hdr_opt(struct bpf_sock_ops *skops, const void *from, u32 len, u64 flags)
4724 * Description
4725 * Store header option. The data will be copied
4726 * from buffer *from* with length *len* to the TCP header.
4727 *
4728 * The buffer *from* should have the whole option that
4729 * includes the kind, kind-length, and the actual
4730 * option data. The *len* must be at least kind-length
4731 * long. The kind-length does not have to be 4 byte
4732 * aligned. The kernel will take care of the padding
4733 * and setting the 4 bytes aligned value to th->doff.
4734 *
4735 * This helper will check for duplicated option
4736 * by searching the same option in the outgoing skb.
4737 *
4738 * This helper can only be called during
4739 * **BPF_SOCK_OPS_WRITE_HDR_OPT_CB**.
4740 *
4741 * Return
4742 * 0 on success, or negative error in case of failure:
4743 *
4744 * **-EINVAL** If param is invalid.
4745 *
4746 * **-ENOSPC** if there is not enough space in the header.
4747 * Nothing has been written
4748 *
4749 * **-EEXIST** if the option already exists.
4750 *
4751 * **-EFAULT** on failure to parse the existing header options.
4752 *
4753 * **-EPERM** if the helper cannot be used under the current
4754 * *skops*\ **->op**.
4755 *
4756 * long bpf_reserve_hdr_opt(struct bpf_sock_ops *skops, u32 len, u64 flags)
4757 * Description
4758 * Reserve *len* bytes for the bpf header option. The
4759 * space will be used by **bpf_store_hdr_opt**\ () later in
4760 * **BPF_SOCK_OPS_WRITE_HDR_OPT_CB**.
4761 *
4762 * If **bpf_reserve_hdr_opt**\ () is called multiple times,
4763 * the total number of bytes will be reserved.
4764 *
4765 * This helper can only be called during
4766 * **BPF_SOCK_OPS_HDR_OPT_LEN_CB**.
4767 *
4768 * Return
4769 * 0 on success, or negative error in case of failure:
4770 *
4771 * **-EINVAL** if a parameter is invalid.
4772 *
4773 * **-ENOSPC** if there is not enough space in the header.
4774 *
4775 * **-EPERM** if the helper cannot be used under the current
4776 * *skops*\ **->op**.
4777 *
4778 * void *bpf_inode_storage_get(struct bpf_map *map, void *inode, void *value, u64 flags)
4779 * Description
4780 * Get a bpf_local_storage from an *inode*.
4781 *
4782 * Logically, it could be thought of as getting the value from
4783 * a *map* with *inode* as the **key**. From this
4784 * perspective, the usage is not much different from
4785 * **bpf_map_lookup_elem**\ (*map*, **&**\ *inode*) except this
4786 * helper enforces the key must be an inode and the map must also
4787 * be a **BPF_MAP_TYPE_INODE_STORAGE**.
4788 *
4789 * Underneath, the value is stored locally at *inode* instead of
4790 * the *map*. The *map* is used as the bpf-local-storage
4791 * "type". The bpf-local-storage "type" (i.e. the *map*) is
4792 * searched against all bpf_local_storage residing at *inode*.
4793 *
4794 * An optional *flags* (**BPF_LOCAL_STORAGE_GET_F_CREATE**) can be
4795 * used such that a new bpf_local_storage will be
4796 * created if one does not exist. *value* can be used
4797 * together with **BPF_LOCAL_STORAGE_GET_F_CREATE** to specify
4798 * the initial value of a bpf_local_storage. If *value* is
4799 * **NULL**, the new bpf_local_storage will be zero initialized.
4800 * Return
4801 * A bpf_local_storage pointer is returned on success.
4802 *
4803 * **NULL** if not found or there was an error in adding
4804 * a new bpf_local_storage.
4805 *
4806 * int bpf_inode_storage_delete(struct bpf_map *map, void *inode)
4807 * Description
4808 * Delete a bpf_local_storage from an *inode*.
4809 * Return
4810 * 0 on success.
4811 *
4812 * **-ENOENT** if the bpf_local_storage cannot be found.
4813 *
4814 * long bpf_d_path(struct path *path, char *buf, u32 sz)
4815 * Description
4816 * Return full path for given **struct path** object, which
4817 * needs to be the kernel BTF *path* object. The path is
4818 * returned in the provided buffer *buf* of size *sz* and
4819 * is zero terminated.
4820 *
4821 * Return
4822 * On success, the strictly positive length of the string,
4823 * including the trailing NUL character. On error, a negative
4824 * value.
4825 *
4826 * long bpf_copy_from_user(void *dst, u32 size, const void *user_ptr)
4827 * Description
4828 * Read *size* bytes from user space address *user_ptr* and store
4829 * the data in *dst*. This is a wrapper of **copy_from_user**\ ().
4830 * Return
4831 * 0 on success, or a negative error in case of failure.
4832 *
4833 * long bpf_snprintf_btf(char *str, u32 str_size, struct btf_ptr *ptr, u32 btf_ptr_size, u64 flags)
4834 * Description
4835 * Use BTF to store a string representation of *ptr*->ptr in *str*,
4836 * using *ptr*->type_id. This value should specify the type
4837 * that *ptr*->ptr points to. LLVM __builtin_btf_type_id(type, 1)
4838 * can be used to look up vmlinux BTF type ids. Traversing the
4839 * data structure using BTF, the type information and values are
4840 * stored in the first *str_size* - 1 bytes of *str*. Safe copy of
4841 * the pointer data is carried out to avoid kernel crashes during
4842 * operation. Smaller types can use string space on the stack;
4843 * larger programs can use map data to store the string
4844 * representation.
4845 *
4846 * The string can be subsequently shared with userspace via
4847 * bpf_perf_event_output() or ring buffer interfaces.
4848 * bpf_trace_printk() is to be avoided as it places too small
4849 * a limit on string size to be useful.
4850 *
4851 * *flags* is a combination of
4852 *
4853 * **BTF_F_COMPACT**
4854 * no formatting around type information
4855 * **BTF_F_NONAME**
4856 * no struct/union member names/types
4857 * **BTF_F_PTR_RAW**
4858 * show raw (unobfuscated) pointer values;
4859 * equivalent to printk specifier %px.
4860 * **BTF_F_ZERO**
4861 * show zero-valued struct/union members; they
4862 * are not displayed by default
4863 *
4864 * Return
4865 * The number of bytes that were written (or would have been
4866 * written if output had to be truncated due to string size),
4867 * or a negative error in cases of failure.
4868 *
4869 * long bpf_seq_printf_btf(struct seq_file *m, struct btf_ptr *ptr, u32 ptr_size, u64 flags)
4870 * Description
4871 * Use BTF to write to seq_write a string representation of
4872 * *ptr*->ptr, using *ptr*->type_id as per bpf_snprintf_btf().
4873 * *flags* are identical to those used for bpf_snprintf_btf.
4874 * Return
4875 * 0 on success or a negative error in case of failure.
4876 *
4877 * u64 bpf_skb_cgroup_classid(struct sk_buff *skb)
4878 * Description
4879 * See **bpf_get_cgroup_classid**\ () for the main description.
4880 * This helper differs from **bpf_get_cgroup_classid**\ () in that
4881 * the cgroup v1 net_cls class is retrieved only from the *skb*'s
4882 * associated socket instead of the current process.
4883 * Return
4884 * The id is returned or 0 in case the id could not be retrieved.
4885 *
4886 * long bpf_redirect_neigh(u32 ifindex, struct bpf_redir_neigh *params, int plen, u64 flags)
4887 * Description
4888 * Redirect the packet to another net device of index *ifindex*
4889 * and fill in L2 addresses from neighboring subsystem. This helper
4890 * is somewhat similar to **bpf_redirect**\ (), except that it
4891 * populates L2 addresses as well, meaning, internally, the helper
4892 * relies on the neighbor lookup for the L2 address of the nexthop.
4893 *
4894 * The helper will perform a FIB lookup based on the skb's
4895 * networking header to get the address of the next hop, unless
4896 * this is supplied by the caller in the *params* argument. The
4897 * *plen* argument indicates the len of *params* and should be set
4898 * to 0 if *params* is NULL.
4899 *
4900 * The *flags* argument is reserved and must be 0. The helper is
4901 * currently only supported for tc BPF program types, and enabled
4902 * for IPv4 and IPv6 protocols.
4903 * Return
4904 * The helper returns **TC_ACT_REDIRECT** on success or
4905 * **TC_ACT_SHOT** on error.
4906 *
4907 * void *bpf_per_cpu_ptr(const void *percpu_ptr, u32 cpu)
4908 * Description
4909 * Take a pointer to a percpu ksym, *percpu_ptr*, and return a
4910 * pointer to the percpu kernel variable on *cpu*. A ksym is an
4911 * extern variable decorated with '__ksym'. For ksym, there is a
4912 * global var (either static or global) defined of the same name
4913 * in the kernel. The ksym is percpu if the global var is percpu.
4914 * The returned pointer points to the global percpu var on *cpu*.
4915 *
4916 * bpf_per_cpu_ptr() has the same semantic as per_cpu_ptr() in the
4917 * kernel, except that bpf_per_cpu_ptr() may return NULL. This
4918 * happens if *cpu* is larger than nr_cpu_ids. The caller of
4919 * bpf_per_cpu_ptr() must check the returned value.
4920 * Return
4921 * A pointer pointing to the kernel percpu variable on *cpu*, or
4922 * NULL, if *cpu* is invalid.
4923 *
4924 * void *bpf_this_cpu_ptr(const void *percpu_ptr)
4925 * Description
4926 * Take a pointer to a percpu ksym, *percpu_ptr*, and return a
4927 * pointer to the percpu kernel variable on this cpu. See the
4928 * description of 'ksym' in **bpf_per_cpu_ptr**\ ().
4929 *
4930 * bpf_this_cpu_ptr() has the same semantic as this_cpu_ptr() in
4931 * the kernel. Different from **bpf_per_cpu_ptr**\ (), it would
4932 * never return NULL.
4933 * Return
4934 * A pointer pointing to the kernel percpu variable on this cpu.
4935 *
4936 * long bpf_redirect_peer(u32 ifindex, u64 flags)
4937 * Description
4938 * Redirect the packet to another net device of index *ifindex*.
4939 * This helper is somewhat similar to **bpf_redirect**\ (), except
4940 * that the redirection happens to the *ifindex*' peer device and
4941 * the netns switch takes place from ingress to ingress without
4942 * going through the CPU's backlog queue.
4943 *
4944 * The *flags* argument is reserved and must be 0. The helper is
4945 * currently only supported for tc BPF program types at the
4946 * ingress hook and for veth and netkit target device types. The
4947 * peer device must reside in a different network namespace.
4948 * Return
4949 * The helper returns **TC_ACT_REDIRECT** on success or
4950 * **TC_ACT_SHOT** on error.
4951 *
4952 * void *bpf_task_storage_get(struct bpf_map *map, struct task_struct *task, void *value, u64 flags)
4953 * Description
4954 * Get a bpf_local_storage from the *task*.
4955 *
4956 * Logically, it could be thought of as getting the value from
4957 * a *map* with *task* as the **key**. From this
4958 * perspective, the usage is not much different from
4959 * **bpf_map_lookup_elem**\ (*map*, **&**\ *task*) except this
4960 * helper enforces the key must be a task_struct and the map must also
4961 * be a **BPF_MAP_TYPE_TASK_STORAGE**.
4962 *
4963 * Underneath, the value is stored locally at *task* instead of
4964 * the *map*. The *map* is used as the bpf-local-storage
4965 * "type". The bpf-local-storage "type" (i.e. the *map*) is
4966 * searched against all bpf_local_storage residing at *task*.
4967 *
4968 * An optional *flags* (**BPF_LOCAL_STORAGE_GET_F_CREATE**) can be
4969 * used such that a new bpf_local_storage will be
4970 * created if one does not exist. *value* can be used
4971 * together with **BPF_LOCAL_STORAGE_GET_F_CREATE** to specify
4972 * the initial value of a bpf_local_storage. If *value* is
4973 * **NULL**, the new bpf_local_storage will be zero initialized.
4974 * Return
4975 * A bpf_local_storage pointer is returned on success.
4976 *
4977 * **NULL** if not found or there was an error in adding
4978 * a new bpf_local_storage.
4979 *
4980 * long bpf_task_storage_delete(struct bpf_map *map, struct task_struct *task)
4981 * Description
4982 * Delete a bpf_local_storage from a *task*.
4983 * Return
4984 * 0 on success.
4985 *
4986 * **-ENOENT** if the bpf_local_storage cannot be found.
4987 *
4988 * struct task_struct *bpf_get_current_task_btf(void)
4989 * Description
4990 * Return a BTF pointer to the "current" task.
4991 * This pointer can also be used in helpers that accept an
4992 * *ARG_PTR_TO_BTF_ID* of type *task_struct*.
4993 * Return
4994 * Pointer to the current task.
4995 *
4996 * long bpf_bprm_opts_set(struct linux_binprm *bprm, u64 flags)
4997 * Description
4998 * Set or clear certain options on *bprm*:
4999 *
5000 * **BPF_F_BPRM_SECUREEXEC** Set the secureexec bit
5001 * which sets the **AT_SECURE** auxv for glibc. The bit
5002 * is cleared if the flag is not specified.
5003 * Return
5004 * **-EINVAL** if invalid *flags* are passed, zero otherwise.
5005 *
5006 * u64 bpf_ktime_get_coarse_ns(void)
5007 * Description
5008 * Return a coarse-grained version of the time elapsed since
5009 * system boot, in nanoseconds. Does not include time the system
5010 * was suspended.
5011 *
5012 * See: **clock_gettime**\ (**CLOCK_MONOTONIC_COARSE**)
5013 * Return
5014 * Current *ktime*.
5015 *
5016 * long bpf_ima_inode_hash(struct inode *inode, void *dst, u32 size)
5017 * Description
5018 * Returns the stored IMA hash of the *inode* (if it's available).
5019 * If the hash is larger than *size*, then only *size*
5020 * bytes will be copied to *dst*
5021 * Return
5022 * The **hash_algo** is returned on success,
5023 * **-EOPNOTSUP** if IMA is disabled or **-EINVAL** if
5024 * invalid arguments are passed.
5025 *
5026 * struct socket *bpf_sock_from_file(struct file *file)
5027 * Description
5028 * If the given file represents a socket, returns the associated
5029 * socket.
5030 * Return
5031 * A pointer to a struct socket on success or NULL if the file is
5032 * not a socket.
5033 *
5034 * long bpf_check_mtu(void *ctx, u32 ifindex, u32 *mtu_len, s32 len_diff, u64 flags)
5035 * Description
5036 * Check packet size against exceeding MTU of net device (based
5037 * on *ifindex*). This helper will likely be used in combination
5038 * with helpers that adjust/change the packet size.
5039 *
5040 * The argument *len_diff* can be used for querying with a planned
5041 * size change. This allows to check MTU prior to changing packet
5042 * ctx. Providing a *len_diff* adjustment that is larger than the
5043 * actual packet size (resulting in negative packet size) will in
5044 * principle not exceed the MTU, which is why it is not considered
5045 * a failure. Other BPF helpers are needed for performing the
5046 * planned size change; therefore the responsibility for catching
5047 * a negative packet size belongs in those helpers.
5048 *
5049 * Specifying *ifindex* zero means the MTU check is performed
5050 * against the current net device. This is practical if this isn't
5051 * used prior to redirect.
5052 *
5053 * On input *mtu_len* must be a valid pointer, else verifier will
5054 * reject BPF program. If the value *mtu_len* is initialized to
5055 * zero then the ctx packet size is use. When value *mtu_len* is
5056 * provided as input this specify the L3 length that the MTU check
5057 * is done against. Remember XDP and TC length operate at L2, but
5058 * this value is L3 as this correlate to MTU and IP-header tot_len
5059 * values which are L3 (similar behavior as bpf_fib_lookup).
5060 *
5061 * The Linux kernel route table can configure MTUs on a more
5062 * specific per route level, which is not provided by this helper.
5063 * For route level MTU checks use the **bpf_fib_lookup**\ ()
5064 * helper.
5065 *
5066 * *ctx* is either **struct xdp_md** for XDP programs or
5067 * **struct sk_buff** for tc cls_act programs.
5068 *
5069 * The *flags* argument can be a combination of one or more of the
5070 * following values:
5071 *
5072 * **BPF_MTU_CHK_SEGS**
5073 * This flag will only works for *ctx* **struct sk_buff**.
5074 * If packet context contains extra packet segment buffers
5075 * (often knows as GSO skb), then MTU check is harder to
5076 * check at this point, because in transmit path it is
5077 * possible for the skb packet to get re-segmented
5078 * (depending on net device features). This could still be
5079 * a MTU violation, so this flag enables performing MTU
5080 * check against segments, with a different violation
5081 * return code to tell it apart. Check cannot use len_diff.
5082 *
5083 * On return *mtu_len* pointer contains the MTU value of the net
5084 * device. Remember the net device configured MTU is the L3 size,
5085 * which is returned here and XDP and TC length operate at L2.
5086 * Helper take this into account for you, but remember when using
5087 * MTU value in your BPF-code.
5088 *
5089 * Return
5090 * * 0 on success, and populate MTU value in *mtu_len* pointer.
5091 *
5092 * * < 0 if any input argument is invalid (*mtu_len* not updated)
5093 *
5094 * MTU violations return positive values, but also populate MTU
5095 * value in *mtu_len* pointer, as this can be needed for
5096 * implementing PMTU handing:
5097 *
5098 * * **BPF_MTU_CHK_RET_FRAG_NEEDED**
5099 * * **BPF_MTU_CHK_RET_SEGS_TOOBIG**
5100 *
5101 * long bpf_for_each_map_elem(struct bpf_map *map, void *callback_fn, void *callback_ctx, u64 flags)
5102 * Description
5103 * For each element in **map**, call **callback_fn** function with
5104 * **map**, **callback_ctx** and other map-specific parameters.
5105 * The **callback_fn** should be a static function and
5106 * the **callback_ctx** should be a pointer to the stack.
5107 * The **flags** is used to control certain aspects of the helper.
5108 * Currently, the **flags** must be 0.
5109 *
5110 * The following are a list of supported map types and their
5111 * respective expected callback signatures:
5112 *
5113 * BPF_MAP_TYPE_HASH, BPF_MAP_TYPE_PERCPU_HASH,
5114 * BPF_MAP_TYPE_LRU_HASH, BPF_MAP_TYPE_LRU_PERCPU_HASH,
5115 * BPF_MAP_TYPE_ARRAY, BPF_MAP_TYPE_PERCPU_ARRAY
5116 *
5117 * long (\*callback_fn)(struct bpf_map \*map, const void \*key, void \*value, void \*ctx);
5118 *
5119 * For per_cpu maps, the map_value is the value on the cpu where the
5120 * bpf_prog is running.
5121 *
5122 * If **callback_fn** return 0, the helper will continue to the next
5123 * element. If return value is 1, the helper will skip the rest of
5124 * elements and return. Other return values are not used now.
5125 *
5126 * Return
5127 * The number of traversed map elements for success, **-EINVAL** for
5128 * invalid **flags**.
5129 *
5130 * long bpf_snprintf(char *str, u32 str_size, const char *fmt, u64 *data, u32 data_len)
5131 * Description
5132 * Outputs a string into the **str** buffer of size **str_size**
5133 * based on a format string stored in a read-only map pointed by
5134 * **fmt**.
5135 *
5136 * Each format specifier in **fmt** corresponds to one u64 element
5137 * in the **data** array. For strings and pointers where pointees
5138 * are accessed, only the pointer values are stored in the *data*
5139 * array. The *data_len* is the size of *data* in bytes - must be
5140 * a multiple of 8.
5141 *
5142 * Formats **%s** and **%p{i,I}{4,6}** require to read kernel
5143 * memory. Reading kernel memory may fail due to either invalid
5144 * address or valid address but requiring a major memory fault. If
5145 * reading kernel memory fails, the string for **%s** will be an
5146 * empty string, and the ip address for **%p{i,I}{4,6}** will be 0.
5147 * Not returning error to bpf program is consistent with what
5148 * **bpf_trace_printk**\ () does for now.
5149 *
5150 * Return
5151 * The strictly positive length of the formatted string, including
5152 * the trailing zero character. If the return value is greater than
5153 * **str_size**, **str** contains a truncated string, guaranteed to
5154 * be zero-terminated except when **str_size** is 0.
5155 *
5156 * Or **-EBUSY** if the per-CPU memory copy buffer is busy.
5157 *
5158 * long bpf_sys_bpf(u32 cmd, void *attr, u32 attr_size)
5159 * Description
5160 * Execute bpf syscall with given arguments.
5161 * Return
5162 * A syscall result.
5163 *
5164 * long bpf_btf_find_by_name_kind(char *name, int name_sz, u32 kind, int flags)
5165 * Description
5166 * Find BTF type with given name and kind in vmlinux BTF or in module's BTFs.
5167 * Return
5168 * Returns btf_id and btf_obj_fd in lower and upper 32 bits.
5169 *
5170 * long bpf_sys_close(u32 fd)
5171 * Description
5172 * Execute close syscall for given FD.
5173 * Return
5174 * A syscall result.
5175 *
5176 * long bpf_timer_init(struct bpf_timer *timer, struct bpf_map *map, u64 flags)
5177 * Description
5178 * Initialize the timer.
5179 * First 4 bits of *flags* specify clockid.
5180 * Only CLOCK_MONOTONIC, CLOCK_REALTIME, CLOCK_BOOTTIME are allowed.
5181 * All other bits of *flags* are reserved.
5182 * The verifier will reject the program if *timer* is not from
5183 * the same *map*.
5184 * Return
5185 * 0 on success.
5186 * **-EBUSY** if *timer* is already initialized.
5187 * **-EINVAL** if invalid *flags* are passed.
5188 * **-EPERM** if *timer* is in a map that doesn't have any user references.
5189 * The user space should either hold a file descriptor to a map with timers
5190 * or pin such map in bpffs. When map is unpinned or file descriptor is
5191 * closed all timers in the map will be cancelled and freed.
5192 *
5193 * long bpf_timer_set_callback(struct bpf_timer *timer, void *callback_fn)
5194 * Description
5195 * Configure the timer to call *callback_fn* static function.
5196 * Return
5197 * 0 on success.
5198 * **-EINVAL** if *timer* was not initialized with bpf_timer_init() earlier.
5199 * **-EPERM** if *timer* is in a map that doesn't have any user references.
5200 * The user space should either hold a file descriptor to a map with timers
5201 * or pin such map in bpffs. When map is unpinned or file descriptor is
5202 * closed all timers in the map will be cancelled and freed.
5203 *
5204 * long bpf_timer_start(struct bpf_timer *timer, u64 nsecs, u64 flags)
5205 * Description
5206 * Set timer expiration N nanoseconds from the current time. The
5207 * configured callback will be invoked in soft irq context on some cpu
5208 * and will not repeat unless another bpf_timer_start() is made.
5209 * In such case the next invocation can migrate to a different cpu.
5210 * Since struct bpf_timer is a field inside map element the map
5211 * owns the timer. The bpf_timer_set_callback() will increment refcnt
5212 * of BPF program to make sure that callback_fn code stays valid.
5213 * When user space reference to a map reaches zero all timers
5214 * in a map are cancelled and corresponding program's refcnts are
5215 * decremented. This is done to make sure that Ctrl-C of a user
5216 * process doesn't leave any timers running. If map is pinned in
5217 * bpffs the callback_fn can re-arm itself indefinitely.
5218 * bpf_map_update/delete_elem() helpers and user space sys_bpf commands
5219 * cancel and free the timer in the given map element.
5220 * The map can contain timers that invoke callback_fn-s from different
5221 * programs. The same callback_fn can serve different timers from
5222 * different maps if key/value layout matches across maps.
5223 * Every bpf_timer_set_callback() can have different callback_fn.
5224 *
5225 * *flags* can be one of:
5226 *
5227 * **BPF_F_TIMER_ABS**
5228 * Start the timer in absolute expire value instead of the
5229 * default relative one.
5230 * **BPF_F_TIMER_CPU_PIN**
5231 * Timer will be pinned to the CPU of the caller.
5232 *
5233 * Return
5234 * 0 on success.
5235 * **-EINVAL** if *timer* was not initialized with bpf_timer_init() earlier
5236 * or invalid *flags* are passed.
5237 *
5238 * long bpf_timer_cancel(struct bpf_timer *timer)
5239 * Description
5240 * Cancel the timer and wait for callback_fn to finish if it was running.
5241 * Return
5242 * 0 if the timer was not active.
5243 * 1 if the timer was active.
5244 * **-EINVAL** if *timer* was not initialized with bpf_timer_init() earlier.
5245 * **-EDEADLK** if callback_fn tried to call bpf_timer_cancel() on its
5246 * own timer which would have led to a deadlock otherwise.
5247 *
5248 * u64 bpf_get_func_ip(void *ctx)
5249 * Description
5250 * Get address of the traced function (for tracing and kprobe programs).
5251 *
5252 * When called for kprobe program attached as uprobe it returns
5253 * probe address for both entry and return uprobe.
5254 *
5255 * Return
5256 * Address of the traced function for kprobe.
5257 * 0 for kprobes placed within the function (not at the entry).
5258 * Address of the probe for uprobe and return uprobe.
5259 *
5260 * u64 bpf_get_attach_cookie(void *ctx)
5261 * Description
5262 * Get bpf_cookie value provided (optionally) during the program
5263 * attachment. It might be different for each individual
5264 * attachment, even if BPF program itself is the same.
5265 * Expects BPF program context *ctx* as a first argument.
5266 *
5267 * Supported for the following program types:
5268 * - kprobe/uprobe;
5269 * - tracepoint;
5270 * - perf_event.
5271 * Return
5272 * Value specified by user at BPF link creation/attachment time
5273 * or 0, if it was not specified.
5274 *
5275 * long bpf_task_pt_regs(struct task_struct *task)
5276 * Description
5277 * Get the struct pt_regs associated with **task**.
5278 * Return
5279 * A pointer to struct pt_regs.
5280 *
5281 * long bpf_get_branch_snapshot(void *entries, u32 size, u64 flags)
5282 * Description
5283 * Get branch trace from hardware engines like Intel LBR. The
5284 * hardware engine is stopped shortly after the helper is
5285 * called. Therefore, the user need to filter branch entries
5286 * based on the actual use case. To capture branch trace
5287 * before the trigger point of the BPF program, the helper
5288 * should be called at the beginning of the BPF program.
5289 *
5290 * The data is stored as struct perf_branch_entry into output
5291 * buffer *entries*. *size* is the size of *entries* in bytes.
5292 * *flags* is reserved for now and must be zero.
5293 *
5294 * Return
5295 * On success, number of bytes written to *buf*. On error, a
5296 * negative value.
5297 *
5298 * **-EINVAL** if *flags* is not zero.
5299 *
5300 * **-ENOENT** if architecture does not support branch records.
5301 *
5302 * long bpf_trace_vprintk(const char *fmt, u32 fmt_size, const void *data, u32 data_len)
5303 * Description
5304 * Behaves like **bpf_trace_printk**\ () helper, but takes an array of u64
5305 * to format and can handle more format args as a result.
5306 *
5307 * Arguments are to be used as in **bpf_seq_printf**\ () helper.
5308 * Return
5309 * The number of bytes written to the buffer, or a negative error
5310 * in case of failure.
5311 *
5312 * struct unix_sock *bpf_skc_to_unix_sock(void *sk)
5313 * Description
5314 * Dynamically cast a *sk* pointer to a *unix_sock* pointer.
5315 * Return
5316 * *sk* if casting is valid, or **NULL** otherwise.
5317 *
5318 * long bpf_kallsyms_lookup_name(const char *name, int name_sz, int flags, u64 *res)
5319 * Description
5320 * Get the address of a kernel symbol, returned in *res*. *res* is
5321 * set to 0 if the symbol is not found.
5322 * Return
5323 * On success, zero. On error, a negative value.
5324 *
5325 * **-EINVAL** if *flags* is not zero.
5326 *
5327 * **-EINVAL** if string *name* is not the same size as *name_sz*.
5328 *
5329 * **-ENOENT** if symbol is not found.
5330 *
5331 * **-EPERM** if caller does not have permission to obtain kernel address.
5332 *
5333 * long bpf_find_vma(struct task_struct *task, u64 addr, void *callback_fn, void *callback_ctx, u64 flags)
5334 * Description
5335 * Find vma of *task* that contains *addr*, call *callback_fn*
5336 * function with *task*, *vma*, and *callback_ctx*.
5337 * The *callback_fn* should be a static function and
5338 * the *callback_ctx* should be a pointer to the stack.
5339 * The *flags* is used to control certain aspects of the helper.
5340 * Currently, the *flags* must be 0.
5341 *
5342 * The expected callback signature is
5343 *
5344 * long (\*callback_fn)(struct task_struct \*task, struct vm_area_struct \*vma, void \*callback_ctx);
5345 *
5346 * Return
5347 * 0 on success.
5348 * **-ENOENT** if *task->mm* is NULL, or no vma contains *addr*.
5349 * **-EBUSY** if failed to try lock mmap_lock.
5350 * **-EINVAL** for invalid **flags**.
5351 *
5352 * long bpf_loop(u32 nr_loops, void *callback_fn, void *callback_ctx, u64 flags)
5353 * Description
5354 * For **nr_loops**, call **callback_fn** function
5355 * with **callback_ctx** as the context parameter.
5356 * The **callback_fn** should be a static function and
5357 * the **callback_ctx** should be a pointer to the stack.
5358 * The **flags** is used to control certain aspects of the helper.
5359 * Currently, the **flags** must be 0. Currently, nr_loops is
5360 * limited to 1 << 23 (~8 million) loops.
5361 *
5362 * long (\*callback_fn)(u32 index, void \*ctx);
5363 *
5364 * where **index** is the current index in the loop. The index
5365 * is zero-indexed.
5366 *
5367 * If **callback_fn** returns 0, the helper will continue to the next
5368 * loop. If return value is 1, the helper will skip the rest of
5369 * the loops and return. Other return values are not used now,
5370 * and will be rejected by the verifier.
5371 *
5372 * Return
5373 * The number of loops performed, **-EINVAL** for invalid **flags**,
5374 * **-E2BIG** if **nr_loops** exceeds the maximum number of loops.
5375 *
5376 * long bpf_strncmp(const char *s1, u32 s1_sz, const char *s2)
5377 * Description
5378 * Do strncmp() between **s1** and **s2**. **s1** doesn't need
5379 * to be null-terminated and **s1_sz** is the maximum storage
5380 * size of **s1**. **s2** must be a read-only string.
5381 * Return
5382 * An integer less than, equal to, or greater than zero
5383 * if the first **s1_sz** bytes of **s1** is found to be
5384 * less than, to match, or be greater than **s2**.
5385 *
5386 * long bpf_get_func_arg(void *ctx, u32 n, u64 *value)
5387 * Description
5388 * Get **n**-th argument register (zero based) of the traced function (for tracing programs)
5389 * returned in **value**.
5390 *
5391 * Return
5392 * 0 on success.
5393 * **-EINVAL** if n >= argument register count of traced function.
5394 *
5395 * long bpf_get_func_ret(void *ctx, u64 *value)
5396 * Description
5397 * Get return value of the traced function (for tracing programs)
5398 * in **value**.
5399 *
5400 * Return
5401 * 0 on success.
5402 * **-EOPNOTSUPP** for tracing programs other than BPF_TRACE_FEXIT or BPF_MODIFY_RETURN.
5403 *
5404 * long bpf_get_func_arg_cnt(void *ctx)
5405 * Description
5406 * Get number of registers of the traced function (for tracing programs) where
5407 * function arguments are stored in these registers.
5408 *
5409 * Return
5410 * The number of argument registers of the traced function.
5411 *
5412 * int bpf_get_retval(void)
5413 * Description
5414 * Get the BPF program's return value that will be returned to the upper layers.
5415 *
5416 * This helper is currently supported by cgroup programs and only by the hooks
5417 * where BPF program's return value is returned to the userspace via errno.
5418 * Return
5419 * The BPF program's return value.
5420 *
5421 * int bpf_set_retval(int retval)
5422 * Description
5423 * Set the BPF program's return value that will be returned to the upper layers.
5424 *
5425 * This helper is currently supported by cgroup programs and only by the hooks
5426 * where BPF program's return value is returned to the userspace via errno.
5427 *
5428 * Note that there is the following corner case where the program exports an error
5429 * via bpf_set_retval but signals success via 'return 1':
5430 *
5431 * bpf_set_retval(-EPERM);
5432 * return 1;
5433 *
5434 * In this case, the BPF program's return value will use helper's -EPERM. This
5435 * still holds true for cgroup/bind{4,6} which supports extra 'return 3' success case.
5436 *
5437 * Return
5438 * 0 on success, or a negative error in case of failure.
5439 *
5440 * u64 bpf_xdp_get_buff_len(struct xdp_buff *xdp_md)
5441 * Description
5442 * Get the total size of a given xdp buff (linear and paged area)
5443 * Return
5444 * The total size of a given xdp buffer.
5445 *
5446 * long bpf_xdp_load_bytes(struct xdp_buff *xdp_md, u32 offset, void *buf, u32 len)
5447 * Description
5448 * This helper is provided as an easy way to load data from a
5449 * xdp buffer. It can be used to load *len* bytes from *offset* from
5450 * the frame associated to *xdp_md*, into the buffer pointed by
5451 * *buf*.
5452 * Return
5453 * 0 on success, or a negative error in case of failure.
5454 *
5455 * long bpf_xdp_store_bytes(struct xdp_buff *xdp_md, u32 offset, void *buf, u32 len)
5456 * Description
5457 * Store *len* bytes from buffer *buf* into the frame
5458 * associated to *xdp_md*, at *offset*.
5459 * Return
5460 * 0 on success, or a negative error in case of failure.
5461 *
5462 * long bpf_copy_from_user_task(void *dst, u32 size, const void *user_ptr, struct task_struct *tsk, u64 flags)
5463 * Description
5464 * Read *size* bytes from user space address *user_ptr* in *tsk*'s
5465 * address space, and stores the data in *dst*. *flags* is not
5466 * used yet and is provided for future extensibility. This helper
5467 * can only be used by sleepable programs.
5468 * Return
5469 * 0 on success, or a negative error in case of failure. On error
5470 * *dst* buffer is zeroed out.
5471 *
5472 * long bpf_skb_set_tstamp(struct sk_buff *skb, u64 tstamp, u32 tstamp_type)
5473 * Description
5474 * Change the __sk_buff->tstamp_type to *tstamp_type*
5475 * and set *tstamp* to the __sk_buff->tstamp together.
5476 *
5477 * If there is no need to change the __sk_buff->tstamp_type,
5478 * the tstamp value can be directly written to __sk_buff->tstamp
5479 * instead.
5480 *
5481 * BPF_SKB_TSTAMP_DELIVERY_MONO is the only tstamp that
5482 * will be kept during bpf_redirect_*(). A non zero
5483 * *tstamp* must be used with the BPF_SKB_TSTAMP_DELIVERY_MONO
5484 * *tstamp_type*.
5485 *
5486 * A BPF_SKB_TSTAMP_UNSPEC *tstamp_type* can only be used
5487 * with a zero *tstamp*.
5488 *
5489 * Only IPv4 and IPv6 skb->protocol are supported.
5490 *
5491 * This function is most useful when it needs to set a
5492 * mono delivery time to __sk_buff->tstamp and then
5493 * bpf_redirect_*() to the egress of an iface. For example,
5494 * changing the (rcv) timestamp in __sk_buff->tstamp at
5495 * ingress to a mono delivery time and then bpf_redirect_*()
5496 * to sch_fq@phy-dev.
5497 * Return
5498 * 0 on success.
5499 * **-EINVAL** for invalid input
5500 * **-EOPNOTSUPP** for unsupported protocol
5501 *
5502 * long bpf_ima_file_hash(struct file *file, void *dst, u32 size)
5503 * Description
5504 * Returns a calculated IMA hash of the *file*.
5505 * If the hash is larger than *size*, then only *size*
5506 * bytes will be copied to *dst*
5507 * Return
5508 * The **hash_algo** is returned on success,
5509 * **-EOPNOTSUP** if the hash calculation failed or **-EINVAL** if
5510 * invalid arguments are passed.
5511 *
5512 * void *bpf_kptr_xchg(void *map_value, void *ptr)
5513 * Description
5514 * Exchange kptr at pointer *map_value* with *ptr*, and return the
5515 * old value. *ptr* can be NULL, otherwise it must be a referenced
5516 * pointer which will be released when this helper is called.
5517 * Return
5518 * The old value of kptr (which can be NULL). The returned pointer
5519 * if not NULL, is a reference which must be released using its
5520 * corresponding release function, or moved into a BPF map before
5521 * program exit.
5522 *
5523 * void *bpf_map_lookup_percpu_elem(struct bpf_map *map, const void *key, u32 cpu)
5524 * Description
5525 * Perform a lookup in *percpu map* for an entry associated to
5526 * *key* on *cpu*.
5527 * Return
5528 * Map value associated to *key* on *cpu*, or **NULL** if no entry
5529 * was found or *cpu* is invalid.
5530 *
5531 * struct mptcp_sock *bpf_skc_to_mptcp_sock(void *sk)
5532 * Description
5533 * Dynamically cast a *sk* pointer to a *mptcp_sock* pointer.
5534 * Return
5535 * *sk* if casting is valid, or **NULL** otherwise.
5536 *
5537 * long bpf_dynptr_from_mem(void *data, u32 size, u64 flags, struct bpf_dynptr *ptr)
5538 * Description
5539 * Get a dynptr to local memory *data*.
5540 *
5541 * *data* must be a ptr to a map value.
5542 * The maximum *size* supported is DYNPTR_MAX_SIZE.
5543 * *flags* is currently unused.
5544 * Return
5545 * 0 on success, -E2BIG if the size exceeds DYNPTR_MAX_SIZE,
5546 * -EINVAL if flags is not 0.
5547 *
5548 * long bpf_ringbuf_reserve_dynptr(void *ringbuf, u32 size, u64 flags, struct bpf_dynptr *ptr)
5549 * Description
5550 * Reserve *size* bytes of payload in a ring buffer *ringbuf*
5551 * through the dynptr interface. *flags* must be 0.
5552 *
5553 * Please note that a corresponding bpf_ringbuf_submit_dynptr or
5554 * bpf_ringbuf_discard_dynptr must be called on *ptr*, even if the
5555 * reservation fails. This is enforced by the verifier.
5556 * Return
5557 * 0 on success, or a negative error in case of failure.
5558 *
5559 * void bpf_ringbuf_submit_dynptr(struct bpf_dynptr *ptr, u64 flags)
5560 * Description
5561 * Submit reserved ring buffer sample, pointed to by *data*,
5562 * through the dynptr interface. This is a no-op if the dynptr is
5563 * invalid/null.
5564 *
5565 * For more information on *flags*, please see
5566 * 'bpf_ringbuf_submit'.
5567 * Return
5568 * Nothing. Always succeeds.
5569 *
5570 * void bpf_ringbuf_discard_dynptr(struct bpf_dynptr *ptr, u64 flags)
5571 * Description
5572 * Discard reserved ring buffer sample through the dynptr
5573 * interface. This is a no-op if the dynptr is invalid/null.
5574 *
5575 * For more information on *flags*, please see
5576 * 'bpf_ringbuf_discard'.
5577 * Return
5578 * Nothing. Always succeeds.
5579 *
5580 * long bpf_dynptr_read(void *dst, u32 len, const struct bpf_dynptr *src, u32 offset, u64 flags)
5581 * Description
5582 * Read *len* bytes from *src* into *dst*, starting from *offset*
5583 * into *src*.
5584 * *flags* is currently unused.
5585 * Return
5586 * 0 on success, -E2BIG if *offset* + *len* exceeds the length
5587 * of *src*'s data, -EINVAL if *src* is an invalid dynptr or if
5588 * *flags* is not 0.
5589 *
5590 * long bpf_dynptr_write(const struct bpf_dynptr *dst, u32 offset, void *src, u32 len, u64 flags)
5591 * Description
5592 * Write *len* bytes from *src* into *dst*, starting from *offset*
5593 * into *dst*.
5594 *
5595 * *flags* must be 0 except for skb-type dynptrs.
5596 *
5597 * For skb-type dynptrs:
5598 * * All data slices of the dynptr are automatically
5599 * invalidated after **bpf_dynptr_write**\ (). This is
5600 * because writing may pull the skb and change the
5601 * underlying packet buffer.
5602 *
5603 * * For *flags*, please see the flags accepted by
5604 * **bpf_skb_store_bytes**\ ().
5605 * Return
5606 * 0 on success, -E2BIG if *offset* + *len* exceeds the length
5607 * of *dst*'s data, -EINVAL if *dst* is an invalid dynptr or if *dst*
5608 * is a read-only dynptr or if *flags* is not correct. For skb-type dynptrs,
5609 * other errors correspond to errors returned by **bpf_skb_store_bytes**\ ().
5610 *
5611 * void *bpf_dynptr_data(const struct bpf_dynptr *ptr, u32 offset, u32 len)
5612 * Description
5613 * Get a pointer to the underlying dynptr data.
5614 *
5615 * *len* must be a statically known value. The returned data slice
5616 * is invalidated whenever the dynptr is invalidated.
5617 *
5618 * skb and xdp type dynptrs may not use bpf_dynptr_data. They should
5619 * instead use bpf_dynptr_slice and bpf_dynptr_slice_rdwr.
5620 * Return
5621 * Pointer to the underlying dynptr data, NULL if the dynptr is
5622 * read-only, if the dynptr is invalid, or if the offset and length
5623 * is out of bounds.
5624 *
5625 * s64 bpf_tcp_raw_gen_syncookie_ipv4(struct iphdr *iph, struct tcphdr *th, u32 th_len)
5626 * Description
5627 * Try to issue a SYN cookie for the packet with corresponding
5628 * IPv4/TCP headers, *iph* and *th*, without depending on a
5629 * listening socket.
5630 *
5631 * *iph* points to the IPv4 header.
5632 *
5633 * *th* points to the start of the TCP header, while *th_len*
5634 * contains the length of the TCP header (at least
5635 * **sizeof**\ (**struct tcphdr**)).
5636 * Return
5637 * On success, lower 32 bits hold the generated SYN cookie in
5638 * followed by 16 bits which hold the MSS value for that cookie,
5639 * and the top 16 bits are unused.
5640 *
5641 * On failure, the returned value is one of the following:
5642 *
5643 * **-EINVAL** if *th_len* is invalid.
5644 *
5645 * s64 bpf_tcp_raw_gen_syncookie_ipv6(struct ipv6hdr *iph, struct tcphdr *th, u32 th_len)
5646 * Description
5647 * Try to issue a SYN cookie for the packet with corresponding
5648 * IPv6/TCP headers, *iph* and *th*, without depending on a
5649 * listening socket.
5650 *
5651 * *iph* points to the IPv6 header.
5652 *
5653 * *th* points to the start of the TCP header, while *th_len*
5654 * contains the length of the TCP header (at least
5655 * **sizeof**\ (**struct tcphdr**)).
5656 * Return
5657 * On success, lower 32 bits hold the generated SYN cookie in
5658 * followed by 16 bits which hold the MSS value for that cookie,
5659 * and the top 16 bits are unused.
5660 *
5661 * On failure, the returned value is one of the following:
5662 *
5663 * **-EINVAL** if *th_len* is invalid.
5664 *
5665 * **-EPROTONOSUPPORT** if CONFIG_IPV6 is not builtin.
5666 *
5667 * long bpf_tcp_raw_check_syncookie_ipv4(struct iphdr *iph, struct tcphdr *th)
5668 * Description
5669 * Check whether *iph* and *th* contain a valid SYN cookie ACK
5670 * without depending on a listening socket.
5671 *
5672 * *iph* points to the IPv4 header.
5673 *
5674 * *th* points to the TCP header.
5675 * Return
5676 * 0 if *iph* and *th* are a valid SYN cookie ACK.
5677 *
5678 * On failure, the returned value is one of the following:
5679 *
5680 * **-EACCES** if the SYN cookie is not valid.
5681 *
5682 * long bpf_tcp_raw_check_syncookie_ipv6(struct ipv6hdr *iph, struct tcphdr *th)
5683 * Description
5684 * Check whether *iph* and *th* contain a valid SYN cookie ACK
5685 * without depending on a listening socket.
5686 *
5687 * *iph* points to the IPv6 header.
5688 *
5689 * *th* points to the TCP header.
5690 * Return
5691 * 0 if *iph* and *th* are a valid SYN cookie ACK.
5692 *
5693 * On failure, the returned value is one of the following:
5694 *
5695 * **-EACCES** if the SYN cookie is not valid.
5696 *
5697 * **-EPROTONOSUPPORT** if CONFIG_IPV6 is not builtin.
5698 *
5699 * u64 bpf_ktime_get_tai_ns(void)
5700 * Description
5701 * A nonsettable system-wide clock derived from wall-clock time but
5702 * ignoring leap seconds. This clock does not experience
5703 * discontinuities and backwards jumps caused by NTP inserting leap
5704 * seconds as CLOCK_REALTIME does.
5705 *
5706 * See: **clock_gettime**\ (**CLOCK_TAI**)
5707 * Return
5708 * Current *ktime*.
5709 *
5710 * long bpf_user_ringbuf_drain(struct bpf_map *map, void *callback_fn, void *ctx, u64 flags)
5711 * Description
5712 * Drain samples from the specified user ring buffer, and invoke
5713 * the provided callback for each such sample:
5714 *
5715 * long (\*callback_fn)(const struct bpf_dynptr \*dynptr, void \*ctx);
5716 *
5717 * If **callback_fn** returns 0, the helper will continue to try
5718 * and drain the next sample, up to a maximum of
5719 * BPF_MAX_USER_RINGBUF_SAMPLES samples. If the return value is 1,
5720 * the helper will skip the rest of the samples and return. Other
5721 * return values are not used now, and will be rejected by the
5722 * verifier.
5723 * Return
5724 * The number of drained samples if no error was encountered while
5725 * draining samples, or 0 if no samples were present in the ring
5726 * buffer. If a user-space producer was epoll-waiting on this map,
5727 * and at least one sample was drained, they will receive an event
5728 * notification notifying them of available space in the ring
5729 * buffer. If the BPF_RB_NO_WAKEUP flag is passed to this
5730 * function, no wakeup notification will be sent. If the
5731 * BPF_RB_FORCE_WAKEUP flag is passed, a wakeup notification will
5732 * be sent even if no sample was drained.
5733 *
5734 * On failure, the returned value is one of the following:
5735 *
5736 * **-EBUSY** if the ring buffer is contended, and another calling
5737 * context was concurrently draining the ring buffer.
5738 *
5739 * **-EINVAL** if user-space is not properly tracking the ring
5740 * buffer due to the producer position not being aligned to 8
5741 * bytes, a sample not being aligned to 8 bytes, or the producer
5742 * position not matching the advertised length of a sample.
5743 *
5744 * **-E2BIG** if user-space has tried to publish a sample which is
5745 * larger than the size of the ring buffer, or which cannot fit
5746 * within a struct bpf_dynptr.
5747 *
5748 * void *bpf_cgrp_storage_get(struct bpf_map *map, struct cgroup *cgroup, void *value, u64 flags)
5749 * Description
5750 * Get a bpf_local_storage from the *cgroup*.
5751 *
5752 * Logically, it could be thought of as getting the value from
5753 * a *map* with *cgroup* as the **key**. From this
5754 * perspective, the usage is not much different from
5755 * **bpf_map_lookup_elem**\ (*map*, **&**\ *cgroup*) except this
5756 * helper enforces the key must be a cgroup struct and the map must also
5757 * be a **BPF_MAP_TYPE_CGRP_STORAGE**.
5758 *
5759 * In reality, the local-storage value is embedded directly inside of the
5760 * *cgroup* object itself, rather than being located in the
5761 * **BPF_MAP_TYPE_CGRP_STORAGE** map. When the local-storage value is
5762 * queried for some *map* on a *cgroup* object, the kernel will perform an
5763 * O(n) iteration over all of the live local-storage values for that
5764 * *cgroup* object until the local-storage value for the *map* is found.
5765 *
5766 * An optional *flags* (**BPF_LOCAL_STORAGE_GET_F_CREATE**) can be
5767 * used such that a new bpf_local_storage will be
5768 * created if one does not exist. *value* can be used
5769 * together with **BPF_LOCAL_STORAGE_GET_F_CREATE** to specify
5770 * the initial value of a bpf_local_storage. If *value* is
5771 * **NULL**, the new bpf_local_storage will be zero initialized.
5772 * Return
5773 * A bpf_local_storage pointer is returned on success.
5774 *
5775 * **NULL** if not found or there was an error in adding
5776 * a new bpf_local_storage.
5777 *
5778 * long bpf_cgrp_storage_delete(struct bpf_map *map, struct cgroup *cgroup)
5779 * Description
5780 * Delete a bpf_local_storage from a *cgroup*.
5781 * Return
5782 * 0 on success.
5783 *
5784 * **-ENOENT** if the bpf_local_storage cannot be found.
5785 */
5786#define ___BPF_FUNC_MAPPER(FN, ctx...) \
5787 FN(unspec, 0, ##ctx) \
5788 FN(map_lookup_elem, 1, ##ctx) \
5789 FN(map_update_elem, 2, ##ctx) \
5790 FN(map_delete_elem, 3, ##ctx) \
5791 FN(probe_read, 4, ##ctx) \
5792 FN(ktime_get_ns, 5, ##ctx) \
5793 FN(trace_printk, 6, ##ctx) \
5794 FN(get_prandom_u32, 7, ##ctx) \
5795 FN(get_smp_processor_id, 8, ##ctx) \
5796 FN(skb_store_bytes, 9, ##ctx) \
5797 FN(l3_csum_replace, 10, ##ctx) \
5798 FN(l4_csum_replace, 11, ##ctx) \
5799 FN(tail_call, 12, ##ctx) \
5800 FN(clone_redirect, 13, ##ctx) \
5801 FN(get_current_pid_tgid, 14, ##ctx) \
5802 FN(get_current_uid_gid, 15, ##ctx) \
5803 FN(get_current_comm, 16, ##ctx) \
5804 FN(get_cgroup_classid, 17, ##ctx) \
5805 FN(skb_vlan_push, 18, ##ctx) \
5806 FN(skb_vlan_pop, 19, ##ctx) \
5807 FN(skb_get_tunnel_key, 20, ##ctx) \
5808 FN(skb_set_tunnel_key, 21, ##ctx) \
5809 FN(perf_event_read, 22, ##ctx) \
5810 FN(redirect, 23, ##ctx) \
5811 FN(get_route_realm, 24, ##ctx) \
5812 FN(perf_event_output, 25, ##ctx) \
5813 FN(skb_load_bytes, 26, ##ctx) \
5814 FN(get_stackid, 27, ##ctx) \
5815 FN(csum_diff, 28, ##ctx) \
5816 FN(skb_get_tunnel_opt, 29, ##ctx) \
5817 FN(skb_set_tunnel_opt, 30, ##ctx) \
5818 FN(skb_change_proto, 31, ##ctx) \
5819 FN(skb_change_type, 32, ##ctx) \
5820 FN(skb_under_cgroup, 33, ##ctx) \
5821 FN(get_hash_recalc, 34, ##ctx) \
5822 FN(get_current_task, 35, ##ctx) \
5823 FN(probe_write_user, 36, ##ctx) \
5824 FN(current_task_under_cgroup, 37, ##ctx) \
5825 FN(skb_change_tail, 38, ##ctx) \
5826 FN(skb_pull_data, 39, ##ctx) \
5827 FN(csum_update, 40, ##ctx) \
5828 FN(set_hash_invalid, 41, ##ctx) \
5829 FN(get_numa_node_id, 42, ##ctx) \
5830 FN(skb_change_head, 43, ##ctx) \
5831 FN(xdp_adjust_head, 44, ##ctx) \
5832 FN(probe_read_str, 45, ##ctx) \
5833 FN(get_socket_cookie, 46, ##ctx) \
5834 FN(get_socket_uid, 47, ##ctx) \
5835 FN(set_hash, 48, ##ctx) \
5836 FN(setsockopt, 49, ##ctx) \
5837 FN(skb_adjust_room, 50, ##ctx) \
5838 FN(redirect_map, 51, ##ctx) \
5839 FN(sk_redirect_map, 52, ##ctx) \
5840 FN(sock_map_update, 53, ##ctx) \
5841 FN(xdp_adjust_meta, 54, ##ctx) \
5842 FN(perf_event_read_value, 55, ##ctx) \
5843 FN(perf_prog_read_value, 56, ##ctx) \
5844 FN(getsockopt, 57, ##ctx) \
5845 FN(override_return, 58, ##ctx) \
5846 FN(sock_ops_cb_flags_set, 59, ##ctx) \
5847 FN(msg_redirect_map, 60, ##ctx) \
5848 FN(msg_apply_bytes, 61, ##ctx) \
5849 FN(msg_cork_bytes, 62, ##ctx) \
5850 FN(msg_pull_data, 63, ##ctx) \
5851 FN(bind, 64, ##ctx) \
5852 FN(xdp_adjust_tail, 65, ##ctx) \
5853 FN(skb_get_xfrm_state, 66, ##ctx) \
5854 FN(get_stack, 67, ##ctx) \
5855 FN(skb_load_bytes_relative, 68, ##ctx) \
5856 FN(fib_lookup, 69, ##ctx) \
5857 FN(sock_hash_update, 70, ##ctx) \
5858 FN(msg_redirect_hash, 71, ##ctx) \
5859 FN(sk_redirect_hash, 72, ##ctx) \
5860 FN(lwt_push_encap, 73, ##ctx) \
5861 FN(lwt_seg6_store_bytes, 74, ##ctx) \
5862 FN(lwt_seg6_adjust_srh, 75, ##ctx) \
5863 FN(lwt_seg6_action, 76, ##ctx) \
5864 FN(rc_repeat, 77, ##ctx) \
5865 FN(rc_keydown, 78, ##ctx) \
5866 FN(skb_cgroup_id, 79, ##ctx) \
5867 FN(get_current_cgroup_id, 80, ##ctx) \
5868 FN(get_local_storage, 81, ##ctx) \
5869 FN(sk_select_reuseport, 82, ##ctx) \
5870 FN(skb_ancestor_cgroup_id, 83, ##ctx) \
5871 FN(sk_lookup_tcp, 84, ##ctx) \
5872 FN(sk_lookup_udp, 85, ##ctx) \
5873 FN(sk_release, 86, ##ctx) \
5874 FN(map_push_elem, 87, ##ctx) \
5875 FN(map_pop_elem, 88, ##ctx) \
5876 FN(map_peek_elem, 89, ##ctx) \
5877 FN(msg_push_data, 90, ##ctx) \
5878 FN(msg_pop_data, 91, ##ctx) \
5879 FN(rc_pointer_rel, 92, ##ctx) \
5880 FN(spin_lock, 93, ##ctx) \
5881 FN(spin_unlock, 94, ##ctx) \
5882 FN(sk_fullsock, 95, ##ctx) \
5883 FN(tcp_sock, 96, ##ctx) \
5884 FN(skb_ecn_set_ce, 97, ##ctx) \
5885 FN(get_listener_sock, 98, ##ctx) \
5886 FN(skc_lookup_tcp, 99, ##ctx) \
5887 FN(tcp_check_syncookie, 100, ##ctx) \
5888 FN(sysctl_get_name, 101, ##ctx) \
5889 FN(sysctl_get_current_value, 102, ##ctx) \
5890 FN(sysctl_get_new_value, 103, ##ctx) \
5891 FN(sysctl_set_new_value, 104, ##ctx) \
5892 FN(strtol, 105, ##ctx) \
5893 FN(strtoul, 106, ##ctx) \
5894 FN(sk_storage_get, 107, ##ctx) \
5895 FN(sk_storage_delete, 108, ##ctx) \
5896 FN(send_signal, 109, ##ctx) \
5897 FN(tcp_gen_syncookie, 110, ##ctx) \
5898 FN(skb_output, 111, ##ctx) \
5899 FN(probe_read_user, 112, ##ctx) \
5900 FN(probe_read_kernel, 113, ##ctx) \
5901 FN(probe_read_user_str, 114, ##ctx) \
5902 FN(probe_read_kernel_str, 115, ##ctx) \
5903 FN(tcp_send_ack, 116, ##ctx) \
5904 FN(send_signal_thread, 117, ##ctx) \
5905 FN(jiffies64, 118, ##ctx) \
5906 FN(read_branch_records, 119, ##ctx) \
5907 FN(get_ns_current_pid_tgid, 120, ##ctx) \
5908 FN(xdp_output, 121, ##ctx) \
5909 FN(get_netns_cookie, 122, ##ctx) \
5910 FN(get_current_ancestor_cgroup_id, 123, ##ctx) \
5911 FN(sk_assign, 124, ##ctx) \
5912 FN(ktime_get_boot_ns, 125, ##ctx) \
5913 FN(seq_printf, 126, ##ctx) \
5914 FN(seq_write, 127, ##ctx) \
5915 FN(sk_cgroup_id, 128, ##ctx) \
5916 FN(sk_ancestor_cgroup_id, 129, ##ctx) \
5917 FN(ringbuf_output, 130, ##ctx) \
5918 FN(ringbuf_reserve, 131, ##ctx) \
5919 FN(ringbuf_submit, 132, ##ctx) \
5920 FN(ringbuf_discard, 133, ##ctx) \
5921 FN(ringbuf_query, 134, ##ctx) \
5922 FN(csum_level, 135, ##ctx) \
5923 FN(skc_to_tcp6_sock, 136, ##ctx) \
5924 FN(skc_to_tcp_sock, 137, ##ctx) \
5925 FN(skc_to_tcp_timewait_sock, 138, ##ctx) \
5926 FN(skc_to_tcp_request_sock, 139, ##ctx) \
5927 FN(skc_to_udp6_sock, 140, ##ctx) \
5928 FN(get_task_stack, 141, ##ctx) \
5929 FN(load_hdr_opt, 142, ##ctx) \
5930 FN(store_hdr_opt, 143, ##ctx) \
5931 FN(reserve_hdr_opt, 144, ##ctx) \
5932 FN(inode_storage_get, 145, ##ctx) \
5933 FN(inode_storage_delete, 146, ##ctx) \
5934 FN(d_path, 147, ##ctx) \
5935 FN(copy_from_user, 148, ##ctx) \
5936 FN(snprintf_btf, 149, ##ctx) \
5937 FN(seq_printf_btf, 150, ##ctx) \
5938 FN(skb_cgroup_classid, 151, ##ctx) \
5939 FN(redirect_neigh, 152, ##ctx) \
5940 FN(per_cpu_ptr, 153, ##ctx) \
5941 FN(this_cpu_ptr, 154, ##ctx) \
5942 FN(redirect_peer, 155, ##ctx) \
5943 FN(task_storage_get, 156, ##ctx) \
5944 FN(task_storage_delete, 157, ##ctx) \
5945 FN(get_current_task_btf, 158, ##ctx) \
5946 FN(bprm_opts_set, 159, ##ctx) \
5947 FN(ktime_get_coarse_ns, 160, ##ctx) \
5948 FN(ima_inode_hash, 161, ##ctx) \
5949 FN(sock_from_file, 162, ##ctx) \
5950 FN(check_mtu, 163, ##ctx) \
5951 FN(for_each_map_elem, 164, ##ctx) \
5952 FN(snprintf, 165, ##ctx) \
5953 FN(sys_bpf, 166, ##ctx) \
5954 FN(btf_find_by_name_kind, 167, ##ctx) \
5955 FN(sys_close, 168, ##ctx) \
5956 FN(timer_init, 169, ##ctx) \
5957 FN(timer_set_callback, 170, ##ctx) \
5958 FN(timer_start, 171, ##ctx) \
5959 FN(timer_cancel, 172, ##ctx) \
5960 FN(get_func_ip, 173, ##ctx) \
5961 FN(get_attach_cookie, 174, ##ctx) \
5962 FN(task_pt_regs, 175, ##ctx) \
5963 FN(get_branch_snapshot, 176, ##ctx) \
5964 FN(trace_vprintk, 177, ##ctx) \
5965 FN(skc_to_unix_sock, 178, ##ctx) \
5966 FN(kallsyms_lookup_name, 179, ##ctx) \
5967 FN(find_vma, 180, ##ctx) \
5968 FN(loop, 181, ##ctx) \
5969 FN(strncmp, 182, ##ctx) \
5970 FN(get_func_arg, 183, ##ctx) \
5971 FN(get_func_ret, 184, ##ctx) \
5972 FN(get_func_arg_cnt, 185, ##ctx) \
5973 FN(get_retval, 186, ##ctx) \
5974 FN(set_retval, 187, ##ctx) \
5975 FN(xdp_get_buff_len, 188, ##ctx) \
5976 FN(xdp_load_bytes, 189, ##ctx) \
5977 FN(xdp_store_bytes, 190, ##ctx) \
5978 FN(copy_from_user_task, 191, ##ctx) \
5979 FN(skb_set_tstamp, 192, ##ctx) \
5980 FN(ima_file_hash, 193, ##ctx) \
5981 FN(kptr_xchg, 194, ##ctx) \
5982 FN(map_lookup_percpu_elem, 195, ##ctx) \
5983 FN(skc_to_mptcp_sock, 196, ##ctx) \
5984 FN(dynptr_from_mem, 197, ##ctx) \
5985 FN(ringbuf_reserve_dynptr, 198, ##ctx) \
5986 FN(ringbuf_submit_dynptr, 199, ##ctx) \
5987 FN(ringbuf_discard_dynptr, 200, ##ctx) \
5988 FN(dynptr_read, 201, ##ctx) \
5989 FN(dynptr_write, 202, ##ctx) \
5990 FN(dynptr_data, 203, ##ctx) \
5991 FN(tcp_raw_gen_syncookie_ipv4, 204, ##ctx) \
5992 FN(tcp_raw_gen_syncookie_ipv6, 205, ##ctx) \
5993 FN(tcp_raw_check_syncookie_ipv4, 206, ##ctx) \
5994 FN(tcp_raw_check_syncookie_ipv6, 207, ##ctx) \
5995 FN(ktime_get_tai_ns, 208, ##ctx) \
5996 FN(user_ringbuf_drain, 209, ##ctx) \
5997 FN(cgrp_storage_get, 210, ##ctx) \
5998 FN(cgrp_storage_delete, 211, ##ctx) \
5999 /* */
6000
6001/* backwards-compatibility macros for users of __BPF_FUNC_MAPPER that don't
6002 * know or care about integer value that is now passed as second argument
6003 */
6004#define __BPF_FUNC_MAPPER_APPLY(name, value, FN) FN(name),
6005#define __BPF_FUNC_MAPPER(FN) ___BPF_FUNC_MAPPER(__BPF_FUNC_MAPPER_APPLY, FN)
6006
6007/* integer value in 'imm' field of BPF_CALL instruction selects which helper
6008 * function eBPF program intends to call
6009 */
6010#define __BPF_ENUM_FN(x, y) BPF_FUNC_ ## x = y,
6011enum bpf_func_id {
6012 ___BPF_FUNC_MAPPER(__BPF_ENUM_FN)
6013 __BPF_FUNC_MAX_ID,
6014};
6015#undef __BPF_ENUM_FN
6016
6017/* All flags used by eBPF helper functions, placed here. */
6018
6019/* BPF_FUNC_skb_store_bytes flags. */
6020enum {
6021 BPF_F_RECOMPUTE_CSUM = (1ULL << 0),
6022 BPF_F_INVALIDATE_HASH = (1ULL << 1),
6023};
6024
6025/* BPF_FUNC_l3_csum_replace and BPF_FUNC_l4_csum_replace flags.
6026 * First 4 bits are for passing the header field size.
6027 */
6028enum {
6029 BPF_F_HDR_FIELD_MASK = 0xfULL,
6030};
6031
6032/* BPF_FUNC_l4_csum_replace flags. */
6033enum {
6034 BPF_F_PSEUDO_HDR = (1ULL << 4),
6035 BPF_F_MARK_MANGLED_0 = (1ULL << 5),
6036 BPF_F_MARK_ENFORCE = (1ULL << 6),
6037};
6038
6039/* BPF_FUNC_clone_redirect and BPF_FUNC_redirect flags. */
6040enum {
6041 BPF_F_INGRESS = (1ULL << 0),
6042};
6043
6044/* BPF_FUNC_skb_set_tunnel_key and BPF_FUNC_skb_get_tunnel_key flags. */
6045enum {
6046 BPF_F_TUNINFO_IPV6 = (1ULL << 0),
6047};
6048
6049/* flags for both BPF_FUNC_get_stackid and BPF_FUNC_get_stack. */
6050enum {
6051 BPF_F_SKIP_FIELD_MASK = 0xffULL,
6052 BPF_F_USER_STACK = (1ULL << 8),
6053/* flags used by BPF_FUNC_get_stackid only. */
6054 BPF_F_FAST_STACK_CMP = (1ULL << 9),
6055 BPF_F_REUSE_STACKID = (1ULL << 10),
6056/* flags used by BPF_FUNC_get_stack only. */
6057 BPF_F_USER_BUILD_ID = (1ULL << 11),
6058};
6059
6060/* BPF_FUNC_skb_set_tunnel_key flags. */
6061enum {
6062 BPF_F_ZERO_CSUM_TX = (1ULL << 1),
6063 BPF_F_DONT_FRAGMENT = (1ULL << 2),
6064 BPF_F_SEQ_NUMBER = (1ULL << 3),
6065 BPF_F_NO_TUNNEL_KEY = (1ULL << 4),
6066};
6067
6068/* BPF_FUNC_skb_get_tunnel_key flags. */
6069enum {
6070 BPF_F_TUNINFO_FLAGS = (1ULL << 4),
6071};
6072
6073/* BPF_FUNC_perf_event_output, BPF_FUNC_perf_event_read and
6074 * BPF_FUNC_perf_event_read_value flags.
6075 */
6076enum {
6077 BPF_F_INDEX_MASK = 0xffffffffULL,
6078 BPF_F_CURRENT_CPU = BPF_F_INDEX_MASK,
6079/* BPF_FUNC_perf_event_output for sk_buff input context. */
6080 BPF_F_CTXLEN_MASK = (0xfffffULL << 32),
6081};
6082
6083/* Current network namespace */
6084enum {
6085 BPF_F_CURRENT_NETNS = (-1L),
6086};
6087
6088/* BPF_FUNC_csum_level level values. */
6089enum {
6090 BPF_CSUM_LEVEL_QUERY,
6091 BPF_CSUM_LEVEL_INC,
6092 BPF_CSUM_LEVEL_DEC,
6093 BPF_CSUM_LEVEL_RESET,
6094};
6095
6096/* BPF_FUNC_skb_adjust_room flags. */
6097enum {
6098 BPF_F_ADJ_ROOM_FIXED_GSO = (1ULL << 0),
6099 BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 = (1ULL << 1),
6100 BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 = (1ULL << 2),
6101 BPF_F_ADJ_ROOM_ENCAP_L4_GRE = (1ULL << 3),
6102 BPF_F_ADJ_ROOM_ENCAP_L4_UDP = (1ULL << 4),
6103 BPF_F_ADJ_ROOM_NO_CSUM_RESET = (1ULL << 5),
6104 BPF_F_ADJ_ROOM_ENCAP_L2_ETH = (1ULL << 6),
6105 BPF_F_ADJ_ROOM_DECAP_L3_IPV4 = (1ULL << 7),
6106 BPF_F_ADJ_ROOM_DECAP_L3_IPV6 = (1ULL << 8),
6107};
6108
6109enum {
6110 BPF_ADJ_ROOM_ENCAP_L2_MASK = 0xff,
6111 BPF_ADJ_ROOM_ENCAP_L2_SHIFT = 56,
6112};
6113
6114#define BPF_F_ADJ_ROOM_ENCAP_L2(len) (((__u64)len & \
6115 BPF_ADJ_ROOM_ENCAP_L2_MASK) \
6116 << BPF_ADJ_ROOM_ENCAP_L2_SHIFT)
6117
6118/* BPF_FUNC_sysctl_get_name flags. */
6119enum {
6120 BPF_F_SYSCTL_BASE_NAME = (1ULL << 0),
6121};
6122
6123/* BPF_FUNC_<kernel_obj>_storage_get flags */
6124enum {
6125 BPF_LOCAL_STORAGE_GET_F_CREATE = (1ULL << 0),
6126 /* BPF_SK_STORAGE_GET_F_CREATE is only kept for backward compatibility
6127 * and BPF_LOCAL_STORAGE_GET_F_CREATE must be used instead.
6128 */
6129 BPF_SK_STORAGE_GET_F_CREATE = BPF_LOCAL_STORAGE_GET_F_CREATE,
6130};
6131
6132/* BPF_FUNC_read_branch_records flags. */
6133enum {
6134 BPF_F_GET_BRANCH_RECORDS_SIZE = (1ULL << 0),
6135};
6136
6137/* BPF_FUNC_bpf_ringbuf_commit, BPF_FUNC_bpf_ringbuf_discard, and
6138 * BPF_FUNC_bpf_ringbuf_output flags.
6139 */
6140enum {
6141 BPF_RB_NO_WAKEUP = (1ULL << 0),
6142 BPF_RB_FORCE_WAKEUP = (1ULL << 1),
6143};
6144
6145/* BPF_FUNC_bpf_ringbuf_query flags */
6146enum {
6147 BPF_RB_AVAIL_DATA = 0,
6148 BPF_RB_RING_SIZE = 1,
6149 BPF_RB_CONS_POS = 2,
6150 BPF_RB_PROD_POS = 3,
6151};
6152
6153/* BPF ring buffer constants */
6154enum {
6155 BPF_RINGBUF_BUSY_BIT = (1U << 31),
6156 BPF_RINGBUF_DISCARD_BIT = (1U << 30),
6157 BPF_RINGBUF_HDR_SZ = 8,
6158};
6159
6160/* BPF_FUNC_sk_assign flags in bpf_sk_lookup context. */
6161enum {
6162 BPF_SK_LOOKUP_F_REPLACE = (1ULL << 0),
6163 BPF_SK_LOOKUP_F_NO_REUSEPORT = (1ULL << 1),
6164};
6165
6166/* Mode for BPF_FUNC_skb_adjust_room helper. */
6167enum bpf_adj_room_mode {
6168 BPF_ADJ_ROOM_NET,
6169 BPF_ADJ_ROOM_MAC,
6170};
6171
6172/* Mode for BPF_FUNC_skb_load_bytes_relative helper. */
6173enum bpf_hdr_start_off {
6174 BPF_HDR_START_MAC,
6175 BPF_HDR_START_NET,
6176};
6177
6178/* Encapsulation type for BPF_FUNC_lwt_push_encap helper. */
6179enum bpf_lwt_encap_mode {
6180 BPF_LWT_ENCAP_SEG6,
6181 BPF_LWT_ENCAP_SEG6_INLINE,
6182 BPF_LWT_ENCAP_IP,
6183};
6184
6185/* Flags for bpf_bprm_opts_set helper */
6186enum {
6187 BPF_F_BPRM_SECUREEXEC = (1ULL << 0),
6188};
6189
6190/* Flags for bpf_redirect_map helper */
6191enum {
6192 BPF_F_BROADCAST = (1ULL << 3),
6193 BPF_F_EXCLUDE_INGRESS = (1ULL << 4),
6194};
6195
6196#define __bpf_md_ptr(type, name) \
6197union { \
6198 type name; \
6199 __u64 :64; \
6200} __attribute__((aligned(8)))
6201
6202enum {
6203 BPF_SKB_TSTAMP_UNSPEC,
6204 BPF_SKB_TSTAMP_DELIVERY_MONO, /* tstamp has mono delivery time */
6205 /* For any BPF_SKB_TSTAMP_* that the bpf prog cannot handle,
6206 * the bpf prog should handle it like BPF_SKB_TSTAMP_UNSPEC
6207 * and try to deduce it by ingress, egress or skb->sk->sk_clockid.
6208 */
6209};
6210
6211/* user accessible mirror of in-kernel sk_buff.
6212 * new fields can only be added to the end of this structure
6213 */
6214struct __sk_buff {
6215 __u32 len;
6216 __u32 pkt_type;
6217 __u32 mark;
6218 __u32 queue_mapping;
6219 __u32 protocol;
6220 __u32 vlan_present;
6221 __u32 vlan_tci;
6222 __u32 vlan_proto;
6223 __u32 priority;
6224 __u32 ingress_ifindex;
6225 __u32 ifindex;
6226 __u32 tc_index;
6227 __u32 cb[5];
6228 __u32 hash;
6229 __u32 tc_classid;
6230 __u32 data;
6231 __u32 data_end;
6232 __u32 napi_id;
6233
6234 /* Accessed by BPF_PROG_TYPE_sk_skb types from here to ... */
6235 __u32 family;
6236 __u32 remote_ip4; /* Stored in network byte order */
6237 __u32 local_ip4; /* Stored in network byte order */
6238 __u32 remote_ip6[4]; /* Stored in network byte order */
6239 __u32 local_ip6[4]; /* Stored in network byte order */
6240 __u32 remote_port; /* Stored in network byte order */
6241 __u32 local_port; /* stored in host byte order */
6242 /* ... here. */
6243
6244 __u32 data_meta;
6245 __bpf_md_ptr(struct bpf_flow_keys *, flow_keys);
6246 __u64 tstamp;
6247 __u32 wire_len;
6248 __u32 gso_segs;
6249 __bpf_md_ptr(struct bpf_sock *, sk);
6250 __u32 gso_size;
6251 __u8 tstamp_type;
6252 __u32 :24; /* Padding, future use. */
6253 __u64 hwtstamp;
6254};
6255
6256struct bpf_tunnel_key {
6257 __u32 tunnel_id;
6258 union {
6259 __u32 remote_ipv4;
6260 __u32 remote_ipv6[4];
6261 };
6262 __u8 tunnel_tos;
6263 __u8 tunnel_ttl;
6264 union {
6265 __u16 tunnel_ext; /* compat */
6266 __be16 tunnel_flags;
6267 };
6268 __u32 tunnel_label;
6269 union {
6270 __u32 local_ipv4;
6271 __u32 local_ipv6[4];
6272 };
6273};
6274
6275/* user accessible mirror of in-kernel xfrm_state.
6276 * new fields can only be added to the end of this structure
6277 */
6278struct bpf_xfrm_state {
6279 __u32 reqid;
6280 __u32 spi; /* Stored in network byte order */
6281 __u16 family;
6282 __u16 ext; /* Padding, future use. */
6283 union {
6284 __u32 remote_ipv4; /* Stored in network byte order */
6285 __u32 remote_ipv6[4]; /* Stored in network byte order */
6286 };
6287};
6288
6289/* Generic BPF return codes which all BPF program types may support.
6290 * The values are binary compatible with their TC_ACT_* counter-part to
6291 * provide backwards compatibility with existing SCHED_CLS and SCHED_ACT
6292 * programs.
6293 *
6294 * XDP is handled seprately, see XDP_*.
6295 */
6296enum bpf_ret_code {
6297 BPF_OK = 0,
6298 /* 1 reserved */
6299 BPF_DROP = 2,
6300 /* 3-6 reserved */
6301 BPF_REDIRECT = 7,
6302 /* >127 are reserved for prog type specific return codes.
6303 *
6304 * BPF_LWT_REROUTE: used by BPF_PROG_TYPE_LWT_IN and
6305 * BPF_PROG_TYPE_LWT_XMIT to indicate that skb had been
6306 * changed and should be routed based on its new L3 header.
6307 * (This is an L3 redirect, as opposed to L2 redirect
6308 * represented by BPF_REDIRECT above).
6309 */
6310 BPF_LWT_REROUTE = 128,
6311 /* BPF_FLOW_DISSECTOR_CONTINUE: used by BPF_PROG_TYPE_FLOW_DISSECTOR
6312 * to indicate that no custom dissection was performed, and
6313 * fallback to standard dissector is requested.
6314 */
6315 BPF_FLOW_DISSECTOR_CONTINUE = 129,
6316};
6317
6318struct bpf_sock {
6319 __u32 bound_dev_if;
6320 __u32 family;
6321 __u32 type;
6322 __u32 protocol;
6323 __u32 mark;
6324 __u32 priority;
6325 /* IP address also allows 1 and 2 bytes access */
6326 __u32 src_ip4;
6327 __u32 src_ip6[4];
6328 __u32 src_port; /* host byte order */
6329 __be16 dst_port; /* network byte order */
6330 __u16 :16; /* zero padding */
6331 __u32 dst_ip4;
6332 __u32 dst_ip6[4];
6333 __u32 state;
6334 __s32 rx_queue_mapping;
6335};
6336
6337struct bpf_tcp_sock {
6338 __u32 snd_cwnd; /* Sending congestion window */
6339 __u32 srtt_us; /* smoothed round trip time << 3 in usecs */
6340 __u32 rtt_min;
6341 __u32 snd_ssthresh; /* Slow start size threshold */
6342 __u32 rcv_nxt; /* What we want to receive next */
6343 __u32 snd_nxt; /* Next sequence we send */
6344 __u32 snd_una; /* First byte we want an ack for */
6345 __u32 mss_cache; /* Cached effective mss, not including SACKS */
6346 __u32 ecn_flags; /* ECN status bits. */
6347 __u32 rate_delivered; /* saved rate sample: packets delivered */
6348 __u32 rate_interval_us; /* saved rate sample: time elapsed */
6349 __u32 packets_out; /* Packets which are "in flight" */
6350 __u32 retrans_out; /* Retransmitted packets out */
6351 __u32 total_retrans; /* Total retransmits for entire connection */
6352 __u32 segs_in; /* RFC4898 tcpEStatsPerfSegsIn
6353 * total number of segments in.
6354 */
6355 __u32 data_segs_in; /* RFC4898 tcpEStatsPerfDataSegsIn
6356 * total number of data segments in.
6357 */
6358 __u32 segs_out; /* RFC4898 tcpEStatsPerfSegsOut
6359 * The total number of segments sent.
6360 */
6361 __u32 data_segs_out; /* RFC4898 tcpEStatsPerfDataSegsOut
6362 * total number of data segments sent.
6363 */
6364 __u32 lost_out; /* Lost packets */
6365 __u32 sacked_out; /* SACK'd packets */
6366 __u64 bytes_received; /* RFC4898 tcpEStatsAppHCThruOctetsReceived
6367 * sum(delta(rcv_nxt)), or how many bytes
6368 * were acked.
6369 */
6370 __u64 bytes_acked; /* RFC4898 tcpEStatsAppHCThruOctetsAcked
6371 * sum(delta(snd_una)), or how many bytes
6372 * were acked.
6373 */
6374 __u32 dsack_dups; /* RFC4898 tcpEStatsStackDSACKDups
6375 * total number of DSACK blocks received
6376 */
6377 __u32 delivered; /* Total data packets delivered incl. rexmits */
6378 __u32 delivered_ce; /* Like the above but only ECE marked packets */
6379 __u32 icsk_retransmits; /* Number of unrecovered [RTO] timeouts */
6380};
6381
6382struct bpf_sock_tuple {
6383 union {
6384 struct {
6385 __be32 saddr;
6386 __be32 daddr;
6387 __be16 sport;
6388 __be16 dport;
6389 } ipv4;
6390 struct {
6391 __be32 saddr[4];
6392 __be32 daddr[4];
6393 __be16 sport;
6394 __be16 dport;
6395 } ipv6;
6396 };
6397};
6398
6399/* (Simplified) user return codes for tcx prog type.
6400 * A valid tcx program must return one of these defined values. All other
6401 * return codes are reserved for future use. Must remain compatible with
6402 * their TC_ACT_* counter-parts. For compatibility in behavior, unknown
6403 * return codes are mapped to TCX_NEXT.
6404 */
6405enum tcx_action_base {
6406 TCX_NEXT = -1,
6407 TCX_PASS = 0,
6408 TCX_DROP = 2,
6409 TCX_REDIRECT = 7,
6410};
6411
6412struct bpf_xdp_sock {
6413 __u32 queue_id;
6414};
6415
6416#define XDP_PACKET_HEADROOM 256
6417
6418/* User return codes for XDP prog type.
6419 * A valid XDP program must return one of these defined values. All other
6420 * return codes are reserved for future use. Unknown return codes will
6421 * result in packet drops and a warning via bpf_warn_invalid_xdp_action().
6422 */
6423enum xdp_action {
6424 XDP_ABORTED = 0,
6425 XDP_DROP,
6426 XDP_PASS,
6427 XDP_TX,
6428 XDP_REDIRECT,
6429};
6430
6431/* user accessible metadata for XDP packet hook
6432 * new fields must be added to the end of this structure
6433 */
6434struct xdp_md {
6435 __u32 data;
6436 __u32 data_end;
6437 __u32 data_meta;
6438 /* Below access go through struct xdp_rxq_info */
6439 __u32 ingress_ifindex; /* rxq->dev->ifindex */
6440 __u32 rx_queue_index; /* rxq->queue_index */
6441
6442 __u32 egress_ifindex; /* txq->dev->ifindex */
6443};
6444
6445/* DEVMAP map-value layout
6446 *
6447 * The struct data-layout of map-value is a configuration interface.
6448 * New members can only be added to the end of this structure.
6449 */
6450struct bpf_devmap_val {
6451 __u32 ifindex; /* device index */
6452 union {
6453 int fd; /* prog fd on map write */
6454 __u32 id; /* prog id on map read */
6455 } bpf_prog;
6456};
6457
6458/* CPUMAP map-value layout
6459 *
6460 * The struct data-layout of map-value is a configuration interface.
6461 * New members can only be added to the end of this structure.
6462 */
6463struct bpf_cpumap_val {
6464 __u32 qsize; /* queue size to remote target CPU */
6465 union {
6466 int fd; /* prog fd on map write */
6467 __u32 id; /* prog id on map read */
6468 } bpf_prog;
6469};
6470
6471enum sk_action {
6472 SK_DROP = 0,
6473 SK_PASS,
6474};
6475
6476/* user accessible metadata for SK_MSG packet hook, new fields must
6477 * be added to the end of this structure
6478 */
6479struct sk_msg_md {
6480 __bpf_md_ptr(void *, data);
6481 __bpf_md_ptr(void *, data_end);
6482
6483 __u32 family;
6484 __u32 remote_ip4; /* Stored in network byte order */
6485 __u32 local_ip4; /* Stored in network byte order */
6486 __u32 remote_ip6[4]; /* Stored in network byte order */
6487 __u32 local_ip6[4]; /* Stored in network byte order */
6488 __u32 remote_port; /* Stored in network byte order */
6489 __u32 local_port; /* stored in host byte order */
6490 __u32 size; /* Total size of sk_msg */
6491
6492 __bpf_md_ptr(struct bpf_sock *, sk); /* current socket */
6493};
6494
6495struct sk_reuseport_md {
6496 /*
6497 * Start of directly accessible data. It begins from
6498 * the tcp/udp header.
6499 */
6500 __bpf_md_ptr(void *, data);
6501 /* End of directly accessible data */
6502 __bpf_md_ptr(void *, data_end);
6503 /*
6504 * Total length of packet (starting from the tcp/udp header).
6505 * Note that the directly accessible bytes (data_end - data)
6506 * could be less than this "len". Those bytes could be
6507 * indirectly read by a helper "bpf_skb_load_bytes()".
6508 */
6509 __u32 len;
6510 /*
6511 * Eth protocol in the mac header (network byte order). e.g.
6512 * ETH_P_IP(0x0800) and ETH_P_IPV6(0x86DD)
6513 */
6514 __u32 eth_protocol;
6515 __u32 ip_protocol; /* IP protocol. e.g. IPPROTO_TCP, IPPROTO_UDP */
6516 __u32 bind_inany; /* Is sock bound to an INANY address? */
6517 __u32 hash; /* A hash of the packet 4 tuples */
6518 /* When reuse->migrating_sk is NULL, it is selecting a sk for the
6519 * new incoming connection request (e.g. selecting a listen sk for
6520 * the received SYN in the TCP case). reuse->sk is one of the sk
6521 * in the reuseport group. The bpf prog can use reuse->sk to learn
6522 * the local listening ip/port without looking into the skb.
6523 *
6524 * When reuse->migrating_sk is not NULL, reuse->sk is closed and
6525 * reuse->migrating_sk is the socket that needs to be migrated
6526 * to another listening socket. migrating_sk could be a fullsock
6527 * sk that is fully established or a reqsk that is in-the-middle
6528 * of 3-way handshake.
6529 */
6530 __bpf_md_ptr(struct bpf_sock *, sk);
6531 __bpf_md_ptr(struct bpf_sock *, migrating_sk);
6532};
6533
6534#define BPF_TAG_SIZE 8
6535
6536struct bpf_prog_info {
6537 __u32 type;
6538 __u32 id;
6539 __u8 tag[BPF_TAG_SIZE];
6540 __u32 jited_prog_len;
6541 __u32 xlated_prog_len;
6542 __aligned_u64 jited_prog_insns;
6543 __aligned_u64 xlated_prog_insns;
6544 __u64 load_time; /* ns since boottime */
6545 __u32 created_by_uid;
6546 __u32 nr_map_ids;
6547 __aligned_u64 map_ids;
6548 char name[BPF_OBJ_NAME_LEN];
6549 __u32 ifindex;
6550 __u32 gpl_compatible:1;
6551 __u32 :31; /* alignment pad */
6552 __u64 netns_dev;
6553 __u64 netns_ino;
6554 __u32 nr_jited_ksyms;
6555 __u32 nr_jited_func_lens;
6556 __aligned_u64 jited_ksyms;
6557 __aligned_u64 jited_func_lens;
6558 __u32 btf_id;
6559 __u32 func_info_rec_size;
6560 __aligned_u64 func_info;
6561 __u32 nr_func_info;
6562 __u32 nr_line_info;
6563 __aligned_u64 line_info;
6564 __aligned_u64 jited_line_info;
6565 __u32 nr_jited_line_info;
6566 __u32 line_info_rec_size;
6567 __u32 jited_line_info_rec_size;
6568 __u32 nr_prog_tags;
6569 __aligned_u64 prog_tags;
6570 __u64 run_time_ns;
6571 __u64 run_cnt;
6572 __u64 recursion_misses;
6573 __u32 verified_insns;
6574 __u32 attach_btf_obj_id;
6575 __u32 attach_btf_id;
6576} __attribute__((aligned(8)));
6577
6578struct bpf_map_info {
6579 __u32 type;
6580 __u32 id;
6581 __u32 key_size;
6582 __u32 value_size;
6583 __u32 max_entries;
6584 __u32 map_flags;
6585 char name[BPF_OBJ_NAME_LEN];
6586 __u32 ifindex;
6587 __u32 btf_vmlinux_value_type_id;
6588 __u64 netns_dev;
6589 __u64 netns_ino;
6590 __u32 btf_id;
6591 __u32 btf_key_type_id;
6592 __u32 btf_value_type_id;
6593 __u32 btf_vmlinux_id;
6594 __u64 map_extra;
6595} __attribute__((aligned(8)));
6596
6597struct bpf_btf_info {
6598 __aligned_u64 btf;
6599 __u32 btf_size;
6600 __u32 id;
6601 __aligned_u64 name;
6602 __u32 name_len;
6603 __u32 kernel_btf;
6604} __attribute__((aligned(8)));
6605
6606struct bpf_link_info {
6607 __u32 type;
6608 __u32 id;
6609 __u32 prog_id;
6610 union {
6611 struct {
6612 __aligned_u64 tp_name; /* in/out: tp_name buffer ptr */
6613 __u32 tp_name_len; /* in/out: tp_name buffer len */
6614 } raw_tracepoint;
6615 struct {
6616 __u32 attach_type;
6617 __u32 target_obj_id; /* prog_id for PROG_EXT, otherwise btf object id */
6618 __u32 target_btf_id; /* BTF type id inside the object */
6619 } tracing;
6620 struct {
6621 __u64 cgroup_id;
6622 __u32 attach_type;
6623 } cgroup;
6624 struct {
6625 __aligned_u64 target_name; /* in/out: target_name buffer ptr */
6626 __u32 target_name_len; /* in/out: target_name buffer len */
6627
6628 /* If the iter specific field is 32 bits, it can be put
6629 * in the first or second union. Otherwise it should be
6630 * put in the second union.
6631 */
6632 union {
6633 struct {
6634 __u32 map_id;
6635 } map;
6636 };
6637 union {
6638 struct {
6639 __u64 cgroup_id;
6640 __u32 order;
6641 } cgroup;
6642 struct {
6643 __u32 tid;
6644 __u32 pid;
6645 } task;
6646 };
6647 } iter;
6648 struct {
6649 __u32 netns_ino;
6650 __u32 attach_type;
6651 } netns;
6652 struct {
6653 __u32 ifindex;
6654 } xdp;
6655 struct {
6656 __u32 map_id;
6657 } struct_ops;
6658 struct {
6659 __u32 pf;
6660 __u32 hooknum;
6661 __s32 priority;
6662 __u32 flags;
6663 } netfilter;
6664 struct {
6665 __aligned_u64 addrs;
6666 __u32 count; /* in/out: kprobe_multi function count */
6667 __u32 flags;
6668 __u64 missed;
6669 __aligned_u64 cookies;
6670 } kprobe_multi;
6671 struct {
6672 __aligned_u64 path;
6673 __aligned_u64 offsets;
6674 __aligned_u64 ref_ctr_offsets;
6675 __aligned_u64 cookies;
6676 __u32 path_size; /* in/out: real path size on success, including zero byte */
6677 __u32 count; /* in/out: uprobe_multi offsets/ref_ctr_offsets/cookies count */
6678 __u32 flags;
6679 __u32 pid;
6680 } uprobe_multi;
6681 struct {
6682 __u32 type; /* enum bpf_perf_event_type */
6683 __u32 :32;
6684 union {
6685 struct {
6686 __aligned_u64 file_name; /* in/out */
6687 __u32 name_len;
6688 __u32 offset; /* offset from file_name */
6689 __u64 cookie;
6690 } uprobe; /* BPF_PERF_EVENT_UPROBE, BPF_PERF_EVENT_URETPROBE */
6691 struct {
6692 __aligned_u64 func_name; /* in/out */
6693 __u32 name_len;
6694 __u32 offset; /* offset from func_name */
6695 __u64 addr;
6696 __u64 missed;
6697 __u64 cookie;
6698 } kprobe; /* BPF_PERF_EVENT_KPROBE, BPF_PERF_EVENT_KRETPROBE */
6699 struct {
6700 __aligned_u64 tp_name; /* in/out */
6701 __u32 name_len;
6702 __u32 :32;
6703 __u64 cookie;
6704 } tracepoint; /* BPF_PERF_EVENT_TRACEPOINT */
6705 struct {
6706 __u64 config;
6707 __u32 type;
6708 __u32 :32;
6709 __u64 cookie;
6710 } event; /* BPF_PERF_EVENT_EVENT */
6711 };
6712 } perf_event;
6713 struct {
6714 __u32 ifindex;
6715 __u32 attach_type;
6716 } tcx;
6717 struct {
6718 __u32 ifindex;
6719 __u32 attach_type;
6720 } netkit;
6721 };
6722} __attribute__((aligned(8)));
6723
6724/* User bpf_sock_addr struct to access socket fields and sockaddr struct passed
6725 * by user and intended to be used by socket (e.g. to bind to, depends on
6726 * attach type).
6727 */
6728struct bpf_sock_addr {
6729 __u32 user_family; /* Allows 4-byte read, but no write. */
6730 __u32 user_ip4; /* Allows 1,2,4-byte read and 4-byte write.
6731 * Stored in network byte order.
6732 */
6733 __u32 user_ip6[4]; /* Allows 1,2,4,8-byte read and 4,8-byte write.
6734 * Stored in network byte order.
6735 */
6736 __u32 user_port; /* Allows 1,2,4-byte read and 4-byte write.
6737 * Stored in network byte order
6738 */
6739 __u32 family; /* Allows 4-byte read, but no write */
6740 __u32 type; /* Allows 4-byte read, but no write */
6741 __u32 protocol; /* Allows 4-byte read, but no write */
6742 __u32 msg_src_ip4; /* Allows 1,2,4-byte read and 4-byte write.
6743 * Stored in network byte order.
6744 */
6745 __u32 msg_src_ip6[4]; /* Allows 1,2,4,8-byte read and 4,8-byte write.
6746 * Stored in network byte order.
6747 */
6748 __bpf_md_ptr(struct bpf_sock *, sk);
6749};
6750
6751/* User bpf_sock_ops struct to access socket values and specify request ops
6752 * and their replies.
6753 * Some of this fields are in network (bigendian) byte order and may need
6754 * to be converted before use (bpf_ntohl() defined in samples/bpf/bpf_endian.h).
6755 * New fields can only be added at the end of this structure
6756 */
6757struct bpf_sock_ops {
6758 __u32 op;
6759 union {
6760 __u32 args[4]; /* Optionally passed to bpf program */
6761 __u32 reply; /* Returned by bpf program */
6762 __u32 replylong[4]; /* Optionally returned by bpf prog */
6763 };
6764 __u32 family;
6765 __u32 remote_ip4; /* Stored in network byte order */
6766 __u32 local_ip4; /* Stored in network byte order */
6767 __u32 remote_ip6[4]; /* Stored in network byte order */
6768 __u32 local_ip6[4]; /* Stored in network byte order */
6769 __u32 remote_port; /* Stored in network byte order */
6770 __u32 local_port; /* stored in host byte order */
6771 __u32 is_fullsock; /* Some TCP fields are only valid if
6772 * there is a full socket. If not, the
6773 * fields read as zero.
6774 */
6775 __u32 snd_cwnd;
6776 __u32 srtt_us; /* Averaged RTT << 3 in usecs */
6777 __u32 bpf_sock_ops_cb_flags; /* flags defined in uapi/linux/tcp.h */
6778 __u32 state;
6779 __u32 rtt_min;
6780 __u32 snd_ssthresh;
6781 __u32 rcv_nxt;
6782 __u32 snd_nxt;
6783 __u32 snd_una;
6784 __u32 mss_cache;
6785 __u32 ecn_flags;
6786 __u32 rate_delivered;
6787 __u32 rate_interval_us;
6788 __u32 packets_out;
6789 __u32 retrans_out;
6790 __u32 total_retrans;
6791 __u32 segs_in;
6792 __u32 data_segs_in;
6793 __u32 segs_out;
6794 __u32 data_segs_out;
6795 __u32 lost_out;
6796 __u32 sacked_out;
6797 __u32 sk_txhash;
6798 __u64 bytes_received;
6799 __u64 bytes_acked;
6800 __bpf_md_ptr(struct bpf_sock *, sk);
6801 /* [skb_data, skb_data_end) covers the whole TCP header.
6802 *
6803 * BPF_SOCK_OPS_PARSE_HDR_OPT_CB: The packet received
6804 * BPF_SOCK_OPS_HDR_OPT_LEN_CB: Not useful because the
6805 * header has not been written.
6806 * BPF_SOCK_OPS_WRITE_HDR_OPT_CB: The header and options have
6807 * been written so far.
6808 * BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB: The SYNACK that concludes
6809 * the 3WHS.
6810 * BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB: The ACK that concludes
6811 * the 3WHS.
6812 *
6813 * bpf_load_hdr_opt() can also be used to read a particular option.
6814 */
6815 __bpf_md_ptr(void *, skb_data);
6816 __bpf_md_ptr(void *, skb_data_end);
6817 __u32 skb_len; /* The total length of a packet.
6818 * It includes the header, options,
6819 * and payload.
6820 */
6821 __u32 skb_tcp_flags; /* tcp_flags of the header. It provides
6822 * an easy way to check for tcp_flags
6823 * without parsing skb_data.
6824 *
6825 * In particular, the skb_tcp_flags
6826 * will still be available in
6827 * BPF_SOCK_OPS_HDR_OPT_LEN even though
6828 * the outgoing header has not
6829 * been written yet.
6830 */
6831 __u64 skb_hwtstamp;
6832};
6833
6834/* Definitions for bpf_sock_ops_cb_flags */
6835enum {
6836 BPF_SOCK_OPS_RTO_CB_FLAG = (1<<0),
6837 BPF_SOCK_OPS_RETRANS_CB_FLAG = (1<<1),
6838 BPF_SOCK_OPS_STATE_CB_FLAG = (1<<2),
6839 BPF_SOCK_OPS_RTT_CB_FLAG = (1<<3),
6840 /* Call bpf for all received TCP headers. The bpf prog will be
6841 * called under sock_ops->op == BPF_SOCK_OPS_PARSE_HDR_OPT_CB
6842 *
6843 * Please refer to the comment in BPF_SOCK_OPS_PARSE_HDR_OPT_CB
6844 * for the header option related helpers that will be useful
6845 * to the bpf programs.
6846 *
6847 * It could be used at the client/active side (i.e. connect() side)
6848 * when the server told it that the server was in syncookie
6849 * mode and required the active side to resend the bpf-written
6850 * options. The active side can keep writing the bpf-options until
6851 * it received a valid packet from the server side to confirm
6852 * the earlier packet (and options) has been received. The later
6853 * example patch is using it like this at the active side when the
6854 * server is in syncookie mode.
6855 *
6856 * The bpf prog will usually turn this off in the common cases.
6857 */
6858 BPF_SOCK_OPS_PARSE_ALL_HDR_OPT_CB_FLAG = (1<<4),
6859 /* Call bpf when kernel has received a header option that
6860 * the kernel cannot handle. The bpf prog will be called under
6861 * sock_ops->op == BPF_SOCK_OPS_PARSE_HDR_OPT_CB.
6862 *
6863 * Please refer to the comment in BPF_SOCK_OPS_PARSE_HDR_OPT_CB
6864 * for the header option related helpers that will be useful
6865 * to the bpf programs.
6866 */
6867 BPF_SOCK_OPS_PARSE_UNKNOWN_HDR_OPT_CB_FLAG = (1<<5),
6868 /* Call bpf when the kernel is writing header options for the
6869 * outgoing packet. The bpf prog will first be called
6870 * to reserve space in a skb under
6871 * sock_ops->op == BPF_SOCK_OPS_HDR_OPT_LEN_CB. Then
6872 * the bpf prog will be called to write the header option(s)
6873 * under sock_ops->op == BPF_SOCK_OPS_WRITE_HDR_OPT_CB.
6874 *
6875 * Please refer to the comment in BPF_SOCK_OPS_HDR_OPT_LEN_CB
6876 * and BPF_SOCK_OPS_WRITE_HDR_OPT_CB for the header option
6877 * related helpers that will be useful to the bpf programs.
6878 *
6879 * The kernel gets its chance to reserve space and write
6880 * options first before the BPF program does.
6881 */
6882 BPF_SOCK_OPS_WRITE_HDR_OPT_CB_FLAG = (1<<6),
6883/* Mask of all currently supported cb flags */
6884 BPF_SOCK_OPS_ALL_CB_FLAGS = 0x7F,
6885};
6886
6887/* List of known BPF sock_ops operators.
6888 * New entries can only be added at the end
6889 */
6890enum {
6891 BPF_SOCK_OPS_VOID,
6892 BPF_SOCK_OPS_TIMEOUT_INIT, /* Should return SYN-RTO value to use or
6893 * -1 if default value should be used
6894 */
6895 BPF_SOCK_OPS_RWND_INIT, /* Should return initial advertized
6896 * window (in packets) or -1 if default
6897 * value should be used
6898 */
6899 BPF_SOCK_OPS_TCP_CONNECT_CB, /* Calls BPF program right before an
6900 * active connection is initialized
6901 */
6902 BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB, /* Calls BPF program when an
6903 * active connection is
6904 * established
6905 */
6906 BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB, /* Calls BPF program when a
6907 * passive connection is
6908 * established
6909 */
6910 BPF_SOCK_OPS_NEEDS_ECN, /* If connection's congestion control
6911 * needs ECN
6912 */
6913 BPF_SOCK_OPS_BASE_RTT, /* Get base RTT. The correct value is
6914 * based on the path and may be
6915 * dependent on the congestion control
6916 * algorithm. In general it indicates
6917 * a congestion threshold. RTTs above
6918 * this indicate congestion
6919 */
6920 BPF_SOCK_OPS_RTO_CB, /* Called when an RTO has triggered.
6921 * Arg1: value of icsk_retransmits
6922 * Arg2: value of icsk_rto
6923 * Arg3: whether RTO has expired
6924 */
6925 BPF_SOCK_OPS_RETRANS_CB, /* Called when skb is retransmitted.
6926 * Arg1: sequence number of 1st byte
6927 * Arg2: # segments
6928 * Arg3: return value of
6929 * tcp_transmit_skb (0 => success)
6930 */
6931 BPF_SOCK_OPS_STATE_CB, /* Called when TCP changes state.
6932 * Arg1: old_state
6933 * Arg2: new_state
6934 */
6935 BPF_SOCK_OPS_TCP_LISTEN_CB, /* Called on listen(2), right after
6936 * socket transition to LISTEN state.
6937 */
6938 BPF_SOCK_OPS_RTT_CB, /* Called on every RTT.
6939 */
6940 BPF_SOCK_OPS_PARSE_HDR_OPT_CB, /* Parse the header option.
6941 * It will be called to handle
6942 * the packets received at
6943 * an already established
6944 * connection.
6945 *
6946 * sock_ops->skb_data:
6947 * Referring to the received skb.
6948 * It covers the TCP header only.
6949 *
6950 * bpf_load_hdr_opt() can also
6951 * be used to search for a
6952 * particular option.
6953 */
6954 BPF_SOCK_OPS_HDR_OPT_LEN_CB, /* Reserve space for writing the
6955 * header option later in
6956 * BPF_SOCK_OPS_WRITE_HDR_OPT_CB.
6957 * Arg1: bool want_cookie. (in
6958 * writing SYNACK only)
6959 *
6960 * sock_ops->skb_data:
6961 * Not available because no header has
6962 * been written yet.
6963 *
6964 * sock_ops->skb_tcp_flags:
6965 * The tcp_flags of the
6966 * outgoing skb. (e.g. SYN, ACK, FIN).
6967 *
6968 * bpf_reserve_hdr_opt() should
6969 * be used to reserve space.
6970 */
6971 BPF_SOCK_OPS_WRITE_HDR_OPT_CB, /* Write the header options
6972 * Arg1: bool want_cookie. (in
6973 * writing SYNACK only)
6974 *
6975 * sock_ops->skb_data:
6976 * Referring to the outgoing skb.
6977 * It covers the TCP header
6978 * that has already been written
6979 * by the kernel and the
6980 * earlier bpf-progs.
6981 *
6982 * sock_ops->skb_tcp_flags:
6983 * The tcp_flags of the outgoing
6984 * skb. (e.g. SYN, ACK, FIN).
6985 *
6986 * bpf_store_hdr_opt() should
6987 * be used to write the
6988 * option.
6989 *
6990 * bpf_load_hdr_opt() can also
6991 * be used to search for a
6992 * particular option that
6993 * has already been written
6994 * by the kernel or the
6995 * earlier bpf-progs.
6996 */
6997};
6998
6999/* List of TCP states. There is a build check in net/ipv4/tcp.c to detect
7000 * changes between the TCP and BPF versions. Ideally this should never happen.
7001 * If it does, we need to add code to convert them before calling
7002 * the BPF sock_ops function.
7003 */
7004enum {
7005 BPF_TCP_ESTABLISHED = 1,
7006 BPF_TCP_SYN_SENT,
7007 BPF_TCP_SYN_RECV,
7008 BPF_TCP_FIN_WAIT1,
7009 BPF_TCP_FIN_WAIT2,
7010 BPF_TCP_TIME_WAIT,
7011 BPF_TCP_CLOSE,
7012 BPF_TCP_CLOSE_WAIT,
7013 BPF_TCP_LAST_ACK,
7014 BPF_TCP_LISTEN,
7015 BPF_TCP_CLOSING, /* Now a valid state */
7016 BPF_TCP_NEW_SYN_RECV,
7017 BPF_TCP_BOUND_INACTIVE,
7018
7019 BPF_TCP_MAX_STATES /* Leave at the end! */
7020};
7021
7022enum {
7023 TCP_BPF_IW = 1001, /* Set TCP initial congestion window */
7024 TCP_BPF_SNDCWND_CLAMP = 1002, /* Set sndcwnd_clamp */
7025 TCP_BPF_DELACK_MAX = 1003, /* Max delay ack in usecs */
7026 TCP_BPF_RTO_MIN = 1004, /* Min delay ack in usecs */
7027 /* Copy the SYN pkt to optval
7028 *
7029 * BPF_PROG_TYPE_SOCK_OPS only. It is similar to the
7030 * bpf_getsockopt(TCP_SAVED_SYN) but it does not limit
7031 * to only getting from the saved_syn. It can either get the
7032 * syn packet from:
7033 *
7034 * 1. the just-received SYN packet (only available when writing the
7035 * SYNACK). It will be useful when it is not necessary to
7036 * save the SYN packet for latter use. It is also the only way
7037 * to get the SYN during syncookie mode because the syn
7038 * packet cannot be saved during syncookie.
7039 *
7040 * OR
7041 *
7042 * 2. the earlier saved syn which was done by
7043 * bpf_setsockopt(TCP_SAVE_SYN).
7044 *
7045 * The bpf_getsockopt(TCP_BPF_SYN*) option will hide where the
7046 * SYN packet is obtained.
7047 *
7048 * If the bpf-prog does not need the IP[46] header, the
7049 * bpf-prog can avoid parsing the IP header by using
7050 * TCP_BPF_SYN. Otherwise, the bpf-prog can get both
7051 * IP[46] and TCP header by using TCP_BPF_SYN_IP.
7052 *
7053 * >0: Total number of bytes copied
7054 * -ENOSPC: Not enough space in optval. Only optlen number of
7055 * bytes is copied.
7056 * -ENOENT: The SYN skb is not available now and the earlier SYN pkt
7057 * is not saved by setsockopt(TCP_SAVE_SYN).
7058 */
7059 TCP_BPF_SYN = 1005, /* Copy the TCP header */
7060 TCP_BPF_SYN_IP = 1006, /* Copy the IP[46] and TCP header */
7061 TCP_BPF_SYN_MAC = 1007, /* Copy the MAC, IP[46], and TCP header */
7062};
7063
7064enum {
7065 BPF_LOAD_HDR_OPT_TCP_SYN = (1ULL << 0),
7066};
7067
7068/* args[0] value during BPF_SOCK_OPS_HDR_OPT_LEN_CB and
7069 * BPF_SOCK_OPS_WRITE_HDR_OPT_CB.
7070 */
7071enum {
7072 BPF_WRITE_HDR_TCP_CURRENT_MSS = 1, /* Kernel is finding the
7073 * total option spaces
7074 * required for an established
7075 * sk in order to calculate the
7076 * MSS. No skb is actually
7077 * sent.
7078 */
7079 BPF_WRITE_HDR_TCP_SYNACK_COOKIE = 2, /* Kernel is in syncookie mode
7080 * when sending a SYN.
7081 */
7082};
7083
7084struct bpf_perf_event_value {
7085 __u64 counter;
7086 __u64 enabled;
7087 __u64 running;
7088};
7089
7090enum {
7091 BPF_DEVCG_ACC_MKNOD = (1ULL << 0),
7092 BPF_DEVCG_ACC_READ = (1ULL << 1),
7093 BPF_DEVCG_ACC_WRITE = (1ULL << 2),
7094};
7095
7096enum {
7097 BPF_DEVCG_DEV_BLOCK = (1ULL << 0),
7098 BPF_DEVCG_DEV_CHAR = (1ULL << 1),
7099};
7100
7101struct bpf_cgroup_dev_ctx {
7102 /* access_type encoded as (BPF_DEVCG_ACC_* << 16) | BPF_DEVCG_DEV_* */
7103 __u32 access_type;
7104 __u32 major;
7105 __u32 minor;
7106};
7107
7108struct bpf_raw_tracepoint_args {
7109 __u64 args[0];
7110};
7111
7112/* DIRECT: Skip the FIB rules and go to FIB table associated with device
7113 * OUTPUT: Do lookup from egress perspective; default is ingress
7114 */
7115enum {
7116 BPF_FIB_LOOKUP_DIRECT = (1U << 0),
7117 BPF_FIB_LOOKUP_OUTPUT = (1U << 1),
7118 BPF_FIB_LOOKUP_SKIP_NEIGH = (1U << 2),
7119 BPF_FIB_LOOKUP_TBID = (1U << 3),
7120 BPF_FIB_LOOKUP_SRC = (1U << 4),
7121};
7122
7123enum {
7124 BPF_FIB_LKUP_RET_SUCCESS, /* lookup successful */
7125 BPF_FIB_LKUP_RET_BLACKHOLE, /* dest is blackholed; can be dropped */
7126 BPF_FIB_LKUP_RET_UNREACHABLE, /* dest is unreachable; can be dropped */
7127 BPF_FIB_LKUP_RET_PROHIBIT, /* dest not allowed; can be dropped */
7128 BPF_FIB_LKUP_RET_NOT_FWDED, /* packet is not forwarded */
7129 BPF_FIB_LKUP_RET_FWD_DISABLED, /* fwding is not enabled on ingress */
7130 BPF_FIB_LKUP_RET_UNSUPP_LWT, /* fwd requires encapsulation */
7131 BPF_FIB_LKUP_RET_NO_NEIGH, /* no neighbor entry for nh */
7132 BPF_FIB_LKUP_RET_FRAG_NEEDED, /* fragmentation required to fwd */
7133 BPF_FIB_LKUP_RET_NO_SRC_ADDR, /* failed to derive IP src addr */
7134};
7135
7136struct bpf_fib_lookup {
7137 /* input: network family for lookup (AF_INET, AF_INET6)
7138 * output: network family of egress nexthop
7139 */
7140 __u8 family;
7141
7142 /* set if lookup is to consider L4 data - e.g., FIB rules */
7143 __u8 l4_protocol;
7144 __be16 sport;
7145 __be16 dport;
7146
7147 union { /* used for MTU check */
7148 /* input to lookup */
7149 __u16 tot_len; /* L3 length from network hdr (iph->tot_len) */
7150
7151 /* output: MTU value */
7152 __u16 mtu_result;
7153 };
7154 /* input: L3 device index for lookup
7155 * output: device index from FIB lookup
7156 */
7157 __u32 ifindex;
7158
7159 union {
7160 /* inputs to lookup */
7161 __u8 tos; /* AF_INET */
7162 __be32 flowinfo; /* AF_INET6, flow_label + priority */
7163
7164 /* output: metric of fib result (IPv4/IPv6 only) */
7165 __u32 rt_metric;
7166 };
7167
7168 /* input: source address to consider for lookup
7169 * output: source address result from lookup
7170 */
7171 union {
7172 __be32 ipv4_src;
7173 __u32 ipv6_src[4]; /* in6_addr; network order */
7174 };
7175
7176 /* input to bpf_fib_lookup, ipv{4,6}_dst is destination address in
7177 * network header. output: bpf_fib_lookup sets to gateway address
7178 * if FIB lookup returns gateway route
7179 */
7180 union {
7181 __be32 ipv4_dst;
7182 __u32 ipv6_dst[4]; /* in6_addr; network order */
7183 };
7184
7185 union {
7186 struct {
7187 /* output */
7188 __be16 h_vlan_proto;
7189 __be16 h_vlan_TCI;
7190 };
7191 /* input: when accompanied with the
7192 * 'BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_TBID` flags, a
7193 * specific routing table to use for the fib lookup.
7194 */
7195 __u32 tbid;
7196 };
7197
7198 __u8 smac[6]; /* ETH_ALEN */
7199 __u8 dmac[6]; /* ETH_ALEN */
7200};
7201
7202struct bpf_redir_neigh {
7203 /* network family for lookup (AF_INET, AF_INET6) */
7204 __u32 nh_family;
7205 /* network address of nexthop; skips fib lookup to find gateway */
7206 union {
7207 __be32 ipv4_nh;
7208 __u32 ipv6_nh[4]; /* in6_addr; network order */
7209 };
7210};
7211
7212/* bpf_check_mtu flags*/
7213enum bpf_check_mtu_flags {
7214 BPF_MTU_CHK_SEGS = (1U << 0),
7215};
7216
7217enum bpf_check_mtu_ret {
7218 BPF_MTU_CHK_RET_SUCCESS, /* check and lookup successful */
7219 BPF_MTU_CHK_RET_FRAG_NEEDED, /* fragmentation required to fwd */
7220 BPF_MTU_CHK_RET_SEGS_TOOBIG, /* GSO re-segmentation needed to fwd */
7221};
7222
7223enum bpf_task_fd_type {
7224 BPF_FD_TYPE_RAW_TRACEPOINT, /* tp name */
7225 BPF_FD_TYPE_TRACEPOINT, /* tp name */
7226 BPF_FD_TYPE_KPROBE, /* (symbol + offset) or addr */
7227 BPF_FD_TYPE_KRETPROBE, /* (symbol + offset) or addr */
7228 BPF_FD_TYPE_UPROBE, /* filename + offset */
7229 BPF_FD_TYPE_URETPROBE, /* filename + offset */
7230};
7231
7232enum {
7233 BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG = (1U << 0),
7234 BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL = (1U << 1),
7235 BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP = (1U << 2),
7236};
7237
7238struct bpf_flow_keys {
7239 __u16 nhoff;
7240 __u16 thoff;
7241 __u16 addr_proto; /* ETH_P_* of valid addrs */
7242 __u8 is_frag;
7243 __u8 is_first_frag;
7244 __u8 is_encap;
7245 __u8 ip_proto;
7246 __be16 n_proto;
7247 __be16 sport;
7248 __be16 dport;
7249 union {
7250 struct {
7251 __be32 ipv4_src;
7252 __be32 ipv4_dst;
7253 };
7254 struct {
7255 __u32 ipv6_src[4]; /* in6_addr; network order */
7256 __u32 ipv6_dst[4]; /* in6_addr; network order */
7257 };
7258 };
7259 __u32 flags;
7260 __be32 flow_label;
7261};
7262
7263struct bpf_func_info {
7264 __u32 insn_off;
7265 __u32 type_id;
7266};
7267
7268#define BPF_LINE_INFO_LINE_NUM(line_col) ((line_col) >> 10)
7269#define BPF_LINE_INFO_LINE_COL(line_col) ((line_col) & 0x3ff)
7270
7271struct bpf_line_info {
7272 __u32 insn_off;
7273 __u32 file_name_off;
7274 __u32 line_off;
7275 __u32 line_col;
7276};
7277
7278struct bpf_spin_lock {
7279 __u32 val;
7280};
7281
7282struct bpf_timer {
7283 __u64 __opaque[2];
7284} __attribute__((aligned(8)));
7285
7286struct bpf_dynptr {
7287 __u64 __opaque[2];
7288} __attribute__((aligned(8)));
7289
7290struct bpf_list_head {
7291 __u64 __opaque[2];
7292} __attribute__((aligned(8)));
7293
7294struct bpf_list_node {
7295 __u64 __opaque[3];
7296} __attribute__((aligned(8)));
7297
7298struct bpf_rb_root {
7299 __u64 __opaque[2];
7300} __attribute__((aligned(8)));
7301
7302struct bpf_rb_node {
7303 __u64 __opaque[4];
7304} __attribute__((aligned(8)));
7305
7306struct bpf_refcount {
7307 __u32 __opaque[1];
7308} __attribute__((aligned(4)));
7309
7310struct bpf_sysctl {
7311 __u32 write; /* Sysctl is being read (= 0) or written (= 1).
7312 * Allows 1,2,4-byte read, but no write.
7313 */
7314 __u32 file_pos; /* Sysctl file position to read from, write to.
7315 * Allows 1,2,4-byte read an 4-byte write.
7316 */
7317};
7318
7319struct bpf_sockopt {
7320 __bpf_md_ptr(struct bpf_sock *, sk);
7321 __bpf_md_ptr(void *, optval);
7322 __bpf_md_ptr(void *, optval_end);
7323
7324 __s32 level;
7325 __s32 optname;
7326 __s32 optlen;
7327 __s32 retval;
7328};
7329
7330struct bpf_pidns_info {
7331 __u32 pid;
7332 __u32 tgid;
7333};
7334
7335/* User accessible data for SK_LOOKUP programs. Add new fields at the end. */
7336struct bpf_sk_lookup {
7337 union {
7338 __bpf_md_ptr(struct bpf_sock *, sk); /* Selected socket */
7339 __u64 cookie; /* Non-zero if socket was selected in PROG_TEST_RUN */
7340 };
7341
7342 __u32 family; /* Protocol family (AF_INET, AF_INET6) */
7343 __u32 protocol; /* IP protocol (IPPROTO_TCP, IPPROTO_UDP) */
7344 __u32 remote_ip4; /* Network byte order */
7345 __u32 remote_ip6[4]; /* Network byte order */
7346 __be16 remote_port; /* Network byte order */
7347 __u16 :16; /* Zero padding */
7348 __u32 local_ip4; /* Network byte order */
7349 __u32 local_ip6[4]; /* Network byte order */
7350 __u32 local_port; /* Host byte order */
7351 __u32 ingress_ifindex; /* The arriving interface. Determined by inet_iif. */
7352};
7353
7354/*
7355 * struct btf_ptr is used for typed pointer representation; the
7356 * type id is used to render the pointer data as the appropriate type
7357 * via the bpf_snprintf_btf() helper described above. A flags field -
7358 * potentially to specify additional details about the BTF pointer
7359 * (rather than its mode of display) - is included for future use.
7360 * Display flags - BTF_F_* - are passed to bpf_snprintf_btf separately.
7361 */
7362struct btf_ptr {
7363 void *ptr;
7364 __u32 type_id;
7365 __u32 flags; /* BTF ptr flags; unused at present. */
7366};
7367
7368/*
7369 * Flags to control bpf_snprintf_btf() behaviour.
7370 * - BTF_F_COMPACT: no formatting around type information
7371 * - BTF_F_NONAME: no struct/union member names/types
7372 * - BTF_F_PTR_RAW: show raw (unobfuscated) pointer values;
7373 * equivalent to %px.
7374 * - BTF_F_ZERO: show zero-valued struct/union members; they
7375 * are not displayed by default
7376 */
7377enum {
7378 BTF_F_COMPACT = (1ULL << 0),
7379 BTF_F_NONAME = (1ULL << 1),
7380 BTF_F_PTR_RAW = (1ULL << 2),
7381 BTF_F_ZERO = (1ULL << 3),
7382};
7383
7384/* bpf_core_relo_kind encodes which aspect of captured field/type/enum value
7385 * has to be adjusted by relocations. It is emitted by llvm and passed to
7386 * libbpf and later to the kernel.
7387 */
7388enum bpf_core_relo_kind {
7389 BPF_CORE_FIELD_BYTE_OFFSET = 0, /* field byte offset */
7390 BPF_CORE_FIELD_BYTE_SIZE = 1, /* field size in bytes */
7391 BPF_CORE_FIELD_EXISTS = 2, /* field existence in target kernel */
7392 BPF_CORE_FIELD_SIGNED = 3, /* field signedness (0 - unsigned, 1 - signed) */
7393 BPF_CORE_FIELD_LSHIFT_U64 = 4, /* bitfield-specific left bitshift */
7394 BPF_CORE_FIELD_RSHIFT_U64 = 5, /* bitfield-specific right bitshift */
7395 BPF_CORE_TYPE_ID_LOCAL = 6, /* type ID in local BPF object */
7396 BPF_CORE_TYPE_ID_TARGET = 7, /* type ID in target kernel */
7397 BPF_CORE_TYPE_EXISTS = 8, /* type existence in target kernel */
7398 BPF_CORE_TYPE_SIZE = 9, /* type size in bytes */
7399 BPF_CORE_ENUMVAL_EXISTS = 10, /* enum value existence in target kernel */
7400 BPF_CORE_ENUMVAL_VALUE = 11, /* enum value integer value */
7401 BPF_CORE_TYPE_MATCHES = 12, /* type match in target kernel */
7402};
7403
7404/*
7405 * "struct bpf_core_relo" is used to pass relocation data form LLVM to libbpf
7406 * and from libbpf to the kernel.
7407 *
7408 * CO-RE relocation captures the following data:
7409 * - insn_off - instruction offset (in bytes) within a BPF program that needs
7410 * its insn->imm field to be relocated with actual field info;
7411 * - type_id - BTF type ID of the "root" (containing) entity of a relocatable
7412 * type or field;
7413 * - access_str_off - offset into corresponding .BTF string section. String
7414 * interpretation depends on specific relocation kind:
7415 * - for field-based relocations, string encodes an accessed field using
7416 * a sequence of field and array indices, separated by colon (:). It's
7417 * conceptually very close to LLVM's getelementptr ([0]) instruction's
7418 * arguments for identifying offset to a field.
7419 * - for type-based relocations, strings is expected to be just "0";
7420 * - for enum value-based relocations, string contains an index of enum
7421 * value within its enum type;
7422 * - kind - one of enum bpf_core_relo_kind;
7423 *
7424 * Example:
7425 * struct sample {
7426 * int a;
7427 * struct {
7428 * int b[10];
7429 * };
7430 * };
7431 *
7432 * struct sample *s = ...;
7433 * int *x = &s->a; // encoded as "0:0" (a is field #0)
7434 * int *y = &s->b[5]; // encoded as "0:1:0:5" (anon struct is field #1,
7435 * // b is field #0 inside anon struct, accessing elem #5)
7436 * int *z = &s[10]->b; // encoded as "10:1" (ptr is used as an array)
7437 *
7438 * type_id for all relocs in this example will capture BTF type id of
7439 * `struct sample`.
7440 *
7441 * Such relocation is emitted when using __builtin_preserve_access_index()
7442 * Clang built-in, passing expression that captures field address, e.g.:
7443 *
7444 * bpf_probe_read(&dst, sizeof(dst),
7445 * __builtin_preserve_access_index(&src->a.b.c));
7446 *
7447 * In this case Clang will emit field relocation recording necessary data to
7448 * be able to find offset of embedded `a.b.c` field within `src` struct.
7449 *
7450 * [0] https://llvm.org/docs/LangRef.html#getelementptr-instruction
7451 */
7452struct bpf_core_relo {
7453 __u32 insn_off;
7454 __u32 type_id;
7455 __u32 access_str_off;
7456 enum bpf_core_relo_kind kind;
7457};
7458
7459/*
7460 * Flags to control bpf_timer_start() behaviour.
7461 * - BPF_F_TIMER_ABS: Timeout passed is absolute time, by default it is
7462 * relative to current time.
7463 * - BPF_F_TIMER_CPU_PIN: Timer will be pinned to the CPU of the caller.
7464 */
7465enum {
7466 BPF_F_TIMER_ABS = (1ULL << 0),
7467 BPF_F_TIMER_CPU_PIN = (1ULL << 1),
7468};
7469
7470/* BPF numbers iterator state */
7471struct bpf_iter_num {
7472 /* opaque iterator state; having __u64 here allows to preserve correct
7473 * alignment requirements in vmlinux.h, generated from BTF
7474 */
7475 __u64 __opaque[1];
7476} __attribute__((aligned(8)));
7477
7478#endif /* _UAPI__LINUX_BPF_H__ */
7479

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source code of linux/tools/include/uapi/linux/bpf.h