1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * AppArmor security module |
4 | * |
5 | * This file contains AppArmor LSM hooks. |
6 | * |
7 | * Copyright (C) 1998-2008 Novell/SUSE |
8 | * Copyright 2009-2010 Canonical Ltd. |
9 | */ |
10 | |
11 | #include <linux/lsm_hooks.h> |
12 | #include <linux/moduleparam.h> |
13 | #include <linux/mm.h> |
14 | #include <linux/mman.h> |
15 | #include <linux/mount.h> |
16 | #include <linux/namei.h> |
17 | #include <linux/ptrace.h> |
18 | #include <linux/ctype.h> |
19 | #include <linux/sysctl.h> |
20 | #include <linux/audit.h> |
21 | #include <linux/user_namespace.h> |
22 | #include <linux/netfilter_ipv4.h> |
23 | #include <linux/netfilter_ipv6.h> |
24 | #include <linux/zstd.h> |
25 | #include <net/sock.h> |
26 | #include <uapi/linux/mount.h> |
27 | #include <uapi/linux/lsm.h> |
28 | |
29 | #include "include/apparmor.h" |
30 | #include "include/apparmorfs.h" |
31 | #include "include/audit.h" |
32 | #include "include/capability.h" |
33 | #include "include/cred.h" |
34 | #include "include/file.h" |
35 | #include "include/ipc.h" |
36 | #include "include/net.h" |
37 | #include "include/path.h" |
38 | #include "include/label.h" |
39 | #include "include/policy.h" |
40 | #include "include/policy_ns.h" |
41 | #include "include/procattr.h" |
42 | #include "include/mount.h" |
43 | #include "include/secid.h" |
44 | |
45 | /* Flag indicating whether initialization completed */ |
46 | int apparmor_initialized; |
47 | |
48 | union aa_buffer { |
49 | struct list_head list; |
50 | DECLARE_FLEX_ARRAY(char, buffer); |
51 | }; |
52 | |
53 | struct aa_local_cache { |
54 | unsigned int hold; |
55 | unsigned int count; |
56 | struct list_head head; |
57 | }; |
58 | |
59 | #define RESERVE_COUNT 2 |
60 | static int reserve_count = RESERVE_COUNT; |
61 | static int buffer_count; |
62 | |
63 | static LIST_HEAD(aa_global_buffers); |
64 | static DEFINE_SPINLOCK(aa_buffers_lock); |
65 | static DEFINE_PER_CPU(struct aa_local_cache, aa_local_buffers); |
66 | |
67 | /* |
68 | * LSM hook functions |
69 | */ |
70 | |
71 | /* |
72 | * put the associated labels |
73 | */ |
74 | static void apparmor_cred_free(struct cred *cred) |
75 | { |
76 | aa_put_label(l: cred_label(cred)); |
77 | set_cred_label(cred, NULL); |
78 | } |
79 | |
80 | /* |
81 | * allocate the apparmor part of blank credentials |
82 | */ |
83 | static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp) |
84 | { |
85 | set_cred_label(cred, NULL); |
86 | return 0; |
87 | } |
88 | |
89 | /* |
90 | * prepare new cred label for modification by prepare_cred block |
91 | */ |
92 | static int apparmor_cred_prepare(struct cred *new, const struct cred *old, |
93 | gfp_t gfp) |
94 | { |
95 | set_cred_label(cred: new, label: aa_get_newest_label(l: cred_label(cred: old))); |
96 | return 0; |
97 | } |
98 | |
99 | /* |
100 | * transfer the apparmor data to a blank set of creds |
101 | */ |
102 | static void apparmor_cred_transfer(struct cred *new, const struct cred *old) |
103 | { |
104 | set_cred_label(cred: new, label: aa_get_newest_label(l: cred_label(cred: old))); |
105 | } |
106 | |
107 | static void apparmor_task_free(struct task_struct *task) |
108 | { |
109 | |
110 | aa_free_task_ctx(ctx: task_ctx(task)); |
111 | } |
112 | |
113 | static int apparmor_task_alloc(struct task_struct *task, |
114 | unsigned long clone_flags) |
115 | { |
116 | struct aa_task_ctx *new = task_ctx(task); |
117 | |
118 | aa_dup_task_ctx(new, old: task_ctx(current)); |
119 | |
120 | return 0; |
121 | } |
122 | |
123 | static int apparmor_ptrace_access_check(struct task_struct *child, |
124 | unsigned int mode) |
125 | { |
126 | struct aa_label *tracer, *tracee; |
127 | const struct cred *cred; |
128 | int error; |
129 | |
130 | cred = get_task_cred(child); |
131 | tracee = cred_label(cred); /* ref count on cred */ |
132 | tracer = __begin_current_label_crit_section(); |
133 | error = aa_may_ptrace(current_cred(), tracer, tracee_cred: cred, tracee, |
134 | request: (mode & PTRACE_MODE_READ) ? AA_PTRACE_READ |
135 | : AA_PTRACE_TRACE); |
136 | __end_current_label_crit_section(tracer); |
137 | put_cred(cred); |
138 | |
139 | return error; |
140 | } |
141 | |
142 | static int apparmor_ptrace_traceme(struct task_struct *parent) |
143 | { |
144 | struct aa_label *tracer, *tracee; |
145 | const struct cred *cred; |
146 | int error; |
147 | |
148 | tracee = __begin_current_label_crit_section(); |
149 | cred = get_task_cred(parent); |
150 | tracer = cred_label(cred); /* ref count on cred */ |
151 | error = aa_may_ptrace(tracer_cred: cred, tracer, current_cred(), tracee, |
152 | AA_PTRACE_TRACE); |
153 | put_cred(cred); |
154 | __end_current_label_crit_section(tracee); |
155 | |
156 | return error; |
157 | } |
158 | |
159 | /* Derived from security/commoncap.c:cap_capget */ |
160 | static int apparmor_capget(const struct task_struct *target, kernel_cap_t *effective, |
161 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
162 | { |
163 | struct aa_label *label; |
164 | const struct cred *cred; |
165 | |
166 | rcu_read_lock(); |
167 | cred = __task_cred(target); |
168 | label = aa_get_newest_cred_label(cred); |
169 | |
170 | /* |
171 | * cap_capget is stacked ahead of this and will |
172 | * initialize effective and permitted. |
173 | */ |
174 | if (!unconfined(label)) { |
175 | struct aa_profile *profile; |
176 | struct label_it i; |
177 | |
178 | label_for_each_confined(i, label, profile) { |
179 | struct aa_ruleset *rules; |
180 | if (COMPLAIN_MODE(profile)) |
181 | continue; |
182 | rules = list_first_entry(&profile->rules, |
183 | typeof(*rules), list); |
184 | *effective = cap_intersect(a: *effective, |
185 | b: rules->caps.allow); |
186 | *permitted = cap_intersect(a: *permitted, |
187 | b: rules->caps.allow); |
188 | } |
189 | } |
190 | rcu_read_unlock(); |
191 | aa_put_label(l: label); |
192 | |
193 | return 0; |
194 | } |
195 | |
196 | static int apparmor_capable(const struct cred *cred, struct user_namespace *ns, |
197 | int cap, unsigned int opts) |
198 | { |
199 | struct aa_label *label; |
200 | int error = 0; |
201 | |
202 | label = aa_get_newest_cred_label(cred); |
203 | if (!unconfined(label)) |
204 | error = aa_capable(subj_cred: cred, label, cap, opts); |
205 | aa_put_label(l: label); |
206 | |
207 | return error; |
208 | } |
209 | |
210 | /** |
211 | * common_perm - basic common permission check wrapper fn for paths |
212 | * @op: operation being checked |
213 | * @path: path to check permission of (NOT NULL) |
214 | * @mask: requested permissions mask |
215 | * @cond: conditional info for the permission request (NOT NULL) |
216 | * |
217 | * Returns: %0 else error code if error or permission denied |
218 | */ |
219 | static int common_perm(const char *op, const struct path *path, u32 mask, |
220 | struct path_cond *cond) |
221 | { |
222 | struct aa_label *label; |
223 | int error = 0; |
224 | |
225 | label = __begin_current_label_crit_section(); |
226 | if (!unconfined(label)) |
227 | error = aa_path_perm(op, current_cred(), label, path, flags: 0, request: mask, |
228 | cond); |
229 | __end_current_label_crit_section(label); |
230 | |
231 | return error; |
232 | } |
233 | |
234 | /** |
235 | * common_perm_cond - common permission wrapper around inode cond |
236 | * @op: operation being checked |
237 | * @path: location to check (NOT NULL) |
238 | * @mask: requested permissions mask |
239 | * |
240 | * Returns: %0 else error code if error or permission denied |
241 | */ |
242 | static int common_perm_cond(const char *op, const struct path *path, u32 mask) |
243 | { |
244 | vfsuid_t vfsuid = i_uid_into_vfsuid(idmap: mnt_idmap(mnt: path->mnt), |
245 | inode: d_backing_inode(upper: path->dentry)); |
246 | struct path_cond cond = { |
247 | vfsuid_into_kuid(vfsuid), |
248 | d_backing_inode(upper: path->dentry)->i_mode |
249 | }; |
250 | |
251 | if (!path_mediated_fs(dentry: path->dentry)) |
252 | return 0; |
253 | |
254 | return common_perm(op, path, mask, cond: &cond); |
255 | } |
256 | |
257 | /** |
258 | * common_perm_dir_dentry - common permission wrapper when path is dir, dentry |
259 | * @op: operation being checked |
260 | * @dir: directory of the dentry (NOT NULL) |
261 | * @dentry: dentry to check (NOT NULL) |
262 | * @mask: requested permissions mask |
263 | * @cond: conditional info for the permission request (NOT NULL) |
264 | * |
265 | * Returns: %0 else error code if error or permission denied |
266 | */ |
267 | static int common_perm_dir_dentry(const char *op, const struct path *dir, |
268 | struct dentry *dentry, u32 mask, |
269 | struct path_cond *cond) |
270 | { |
271 | struct path path = { .mnt = dir->mnt, .dentry = dentry }; |
272 | |
273 | return common_perm(op, path: &path, mask, cond); |
274 | } |
275 | |
276 | /** |
277 | * common_perm_rm - common permission wrapper for operations doing rm |
278 | * @op: operation being checked |
279 | * @dir: directory that the dentry is in (NOT NULL) |
280 | * @dentry: dentry being rm'd (NOT NULL) |
281 | * @mask: requested permission mask |
282 | * |
283 | * Returns: %0 else error code if error or permission denied |
284 | */ |
285 | static int common_perm_rm(const char *op, const struct path *dir, |
286 | struct dentry *dentry, u32 mask) |
287 | { |
288 | struct inode *inode = d_backing_inode(upper: dentry); |
289 | struct path_cond cond = { }; |
290 | vfsuid_t vfsuid; |
291 | |
292 | if (!inode || !path_mediated_fs(dentry)) |
293 | return 0; |
294 | |
295 | vfsuid = i_uid_into_vfsuid(idmap: mnt_idmap(mnt: dir->mnt), inode); |
296 | cond.uid = vfsuid_into_kuid(vfsuid); |
297 | cond.mode = inode->i_mode; |
298 | |
299 | return common_perm_dir_dentry(op, dir, dentry, mask, cond: &cond); |
300 | } |
301 | |
302 | /** |
303 | * common_perm_create - common permission wrapper for operations doing create |
304 | * @op: operation being checked |
305 | * @dir: directory that dentry will be created in (NOT NULL) |
306 | * @dentry: dentry to create (NOT NULL) |
307 | * @mask: request permission mask |
308 | * @mode: created file mode |
309 | * |
310 | * Returns: %0 else error code if error or permission denied |
311 | */ |
312 | static int common_perm_create(const char *op, const struct path *dir, |
313 | struct dentry *dentry, u32 mask, umode_t mode) |
314 | { |
315 | struct path_cond cond = { current_fsuid(), mode }; |
316 | |
317 | if (!path_mediated_fs(dentry: dir->dentry)) |
318 | return 0; |
319 | |
320 | return common_perm_dir_dentry(op, dir, dentry, mask, cond: &cond); |
321 | } |
322 | |
323 | static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry) |
324 | { |
325 | return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE); |
326 | } |
327 | |
328 | static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry, |
329 | umode_t mode) |
330 | { |
331 | return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE, |
332 | S_IFDIR); |
333 | } |
334 | |
335 | static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry) |
336 | { |
337 | return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE); |
338 | } |
339 | |
340 | static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry, |
341 | umode_t mode, unsigned int dev) |
342 | { |
343 | return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode); |
344 | } |
345 | |
346 | static int apparmor_path_truncate(const struct path *path) |
347 | { |
348 | return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR); |
349 | } |
350 | |
351 | static int apparmor_file_truncate(struct file *file) |
352 | { |
353 | return apparmor_path_truncate(path: &file->f_path); |
354 | } |
355 | |
356 | static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry, |
357 | const char *old_name) |
358 | { |
359 | return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE, |
360 | S_IFLNK); |
361 | } |
362 | |
363 | static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir, |
364 | struct dentry *new_dentry) |
365 | { |
366 | struct aa_label *label; |
367 | int error = 0; |
368 | |
369 | if (!path_mediated_fs(dentry: old_dentry)) |
370 | return 0; |
371 | |
372 | label = begin_current_label_crit_section(); |
373 | if (!unconfined(label)) |
374 | error = aa_path_link(current_cred(), label, old_dentry, new_dir, |
375 | new_dentry); |
376 | end_current_label_crit_section(label); |
377 | |
378 | return error; |
379 | } |
380 | |
381 | static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry, |
382 | const struct path *new_dir, struct dentry *new_dentry, |
383 | const unsigned int flags) |
384 | { |
385 | struct aa_label *label; |
386 | int error = 0; |
387 | |
388 | if (!path_mediated_fs(dentry: old_dentry)) |
389 | return 0; |
390 | if ((flags & RENAME_EXCHANGE) && !path_mediated_fs(dentry: new_dentry)) |
391 | return 0; |
392 | |
393 | label = begin_current_label_crit_section(); |
394 | if (!unconfined(label)) { |
395 | struct mnt_idmap *idmap = mnt_idmap(mnt: old_dir->mnt); |
396 | vfsuid_t vfsuid; |
397 | struct path old_path = { .mnt = old_dir->mnt, |
398 | .dentry = old_dentry }; |
399 | struct path new_path = { .mnt = new_dir->mnt, |
400 | .dentry = new_dentry }; |
401 | struct path_cond cond = { |
402 | .mode = d_backing_inode(upper: old_dentry)->i_mode |
403 | }; |
404 | vfsuid = i_uid_into_vfsuid(idmap, inode: d_backing_inode(upper: old_dentry)); |
405 | cond.uid = vfsuid_into_kuid(vfsuid); |
406 | |
407 | if (flags & RENAME_EXCHANGE) { |
408 | struct path_cond cond_exchange = { |
409 | .mode = d_backing_inode(upper: new_dentry)->i_mode, |
410 | }; |
411 | vfsuid = i_uid_into_vfsuid(idmap, inode: d_backing_inode(upper: old_dentry)); |
412 | cond_exchange.uid = vfsuid_into_kuid(vfsuid); |
413 | |
414 | error = aa_path_perm(OP_RENAME_SRC, current_cred(), |
415 | label, path: &new_path, flags: 0, |
416 | MAY_READ | AA_MAY_GETATTR | MAY_WRITE | |
417 | AA_MAY_SETATTR | AA_MAY_DELETE, |
418 | cond: &cond_exchange); |
419 | if (!error) |
420 | error = aa_path_perm(OP_RENAME_DEST, current_cred(), |
421 | label, path: &old_path, |
422 | flags: 0, MAY_WRITE | AA_MAY_SETATTR | |
423 | AA_MAY_CREATE, cond: &cond_exchange); |
424 | } |
425 | |
426 | if (!error) |
427 | error = aa_path_perm(OP_RENAME_SRC, current_cred(), |
428 | label, path: &old_path, flags: 0, |
429 | MAY_READ | AA_MAY_GETATTR | MAY_WRITE | |
430 | AA_MAY_SETATTR | AA_MAY_DELETE, |
431 | cond: &cond); |
432 | if (!error) |
433 | error = aa_path_perm(OP_RENAME_DEST, current_cred(), |
434 | label, path: &new_path, |
435 | flags: 0, MAY_WRITE | AA_MAY_SETATTR | |
436 | AA_MAY_CREATE, cond: &cond); |
437 | |
438 | } |
439 | end_current_label_crit_section(label); |
440 | |
441 | return error; |
442 | } |
443 | |
444 | static int apparmor_path_chmod(const struct path *path, umode_t mode) |
445 | { |
446 | return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD); |
447 | } |
448 | |
449 | static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid) |
450 | { |
451 | return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN); |
452 | } |
453 | |
454 | static int apparmor_inode_getattr(const struct path *path) |
455 | { |
456 | return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR); |
457 | } |
458 | |
459 | static int apparmor_file_open(struct file *file) |
460 | { |
461 | struct aa_file_ctx *fctx = file_ctx(file); |
462 | struct aa_label *label; |
463 | int error = 0; |
464 | |
465 | if (!path_mediated_fs(dentry: file->f_path.dentry)) |
466 | return 0; |
467 | |
468 | /* If in exec, permission is handled by bprm hooks. |
469 | * Cache permissions granted by the previous exec check, with |
470 | * implicit read and executable mmap which are required to |
471 | * actually execute the image. |
472 | * |
473 | * Illogically, FMODE_EXEC is in f_flags, not f_mode. |
474 | */ |
475 | if (file->f_flags & __FMODE_EXEC) { |
476 | fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP; |
477 | return 0; |
478 | } |
479 | |
480 | label = aa_get_newest_cred_label(cred: file->f_cred); |
481 | if (!unconfined(label)) { |
482 | struct mnt_idmap *idmap = file_mnt_idmap(file); |
483 | struct inode *inode = file_inode(f: file); |
484 | vfsuid_t vfsuid; |
485 | struct path_cond cond = { |
486 | .mode = inode->i_mode, |
487 | }; |
488 | vfsuid = i_uid_into_vfsuid(idmap, inode); |
489 | cond.uid = vfsuid_into_kuid(vfsuid); |
490 | |
491 | error = aa_path_perm(OP_OPEN, subj_cred: file->f_cred, |
492 | label, path: &file->f_path, flags: 0, |
493 | request: aa_map_file_to_perms(file), cond: &cond); |
494 | /* todo cache full allowed permissions set and state */ |
495 | fctx->allow = aa_map_file_to_perms(file); |
496 | } |
497 | aa_put_label(l: label); |
498 | |
499 | return error; |
500 | } |
501 | |
502 | static int apparmor_file_alloc_security(struct file *file) |
503 | { |
504 | struct aa_file_ctx *ctx = file_ctx(file); |
505 | struct aa_label *label = begin_current_label_crit_section(); |
506 | |
507 | spin_lock_init(&ctx->lock); |
508 | rcu_assign_pointer(ctx->label, aa_get_label(label)); |
509 | end_current_label_crit_section(label); |
510 | return 0; |
511 | } |
512 | |
513 | static void apparmor_file_free_security(struct file *file) |
514 | { |
515 | struct aa_file_ctx *ctx = file_ctx(file); |
516 | |
517 | if (ctx) |
518 | aa_put_label(rcu_access_pointer(ctx->label)); |
519 | } |
520 | |
521 | static int common_file_perm(const char *op, struct file *file, u32 mask, |
522 | bool in_atomic) |
523 | { |
524 | struct aa_label *label; |
525 | int error = 0; |
526 | |
527 | /* don't reaudit files closed during inheritance */ |
528 | if (file->f_path.dentry == aa_null.dentry) |
529 | return -EACCES; |
530 | |
531 | label = __begin_current_label_crit_section(); |
532 | error = aa_file_perm(op, current_cred(), label, file, request: mask, in_atomic); |
533 | __end_current_label_crit_section(label); |
534 | |
535 | return error; |
536 | } |
537 | |
538 | static int apparmor_file_receive(struct file *file) |
539 | { |
540 | return common_file_perm(OP_FRECEIVE, file, mask: aa_map_file_to_perms(file), |
541 | in_atomic: false); |
542 | } |
543 | |
544 | static int apparmor_file_permission(struct file *file, int mask) |
545 | { |
546 | return common_file_perm(OP_FPERM, file, mask, in_atomic: false); |
547 | } |
548 | |
549 | static int apparmor_file_lock(struct file *file, unsigned int cmd) |
550 | { |
551 | u32 mask = AA_MAY_LOCK; |
552 | |
553 | if (cmd == F_WRLCK) |
554 | mask |= MAY_WRITE; |
555 | |
556 | return common_file_perm(OP_FLOCK, file, mask, in_atomic: false); |
557 | } |
558 | |
559 | static int common_mmap(const char *op, struct file *file, unsigned long prot, |
560 | unsigned long flags, bool in_atomic) |
561 | { |
562 | int mask = 0; |
563 | |
564 | if (!file || !file_ctx(file)) |
565 | return 0; |
566 | |
567 | if (prot & PROT_READ) |
568 | mask |= MAY_READ; |
569 | /* |
570 | * Private mappings don't require write perms since they don't |
571 | * write back to the files |
572 | */ |
573 | if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE)) |
574 | mask |= MAY_WRITE; |
575 | if (prot & PROT_EXEC) |
576 | mask |= AA_EXEC_MMAP; |
577 | |
578 | return common_file_perm(op, file, mask, in_atomic); |
579 | } |
580 | |
581 | static int apparmor_mmap_file(struct file *file, unsigned long reqprot, |
582 | unsigned long prot, unsigned long flags) |
583 | { |
584 | return common_mmap(OP_FMMAP, file, prot, flags, GFP_ATOMIC); |
585 | } |
586 | |
587 | static int apparmor_file_mprotect(struct vm_area_struct *vma, |
588 | unsigned long reqprot, unsigned long prot) |
589 | { |
590 | return common_mmap(OP_FMPROT, file: vma->vm_file, prot, |
591 | flags: !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0, |
592 | in_atomic: false); |
593 | } |
594 | |
595 | #ifdef CONFIG_IO_URING |
596 | static const char *audit_uring_mask(u32 mask) |
597 | { |
598 | if (mask & AA_MAY_CREATE_SQPOLL) |
599 | return "sqpoll" ; |
600 | if (mask & AA_MAY_OVERRIDE_CRED) |
601 | return "override_creds" ; |
602 | return "" ; |
603 | } |
604 | |
605 | static void audit_uring_cb(struct audit_buffer *ab, void *va) |
606 | { |
607 | struct apparmor_audit_data *ad = aad_of_va(va); |
608 | |
609 | if (ad->request & AA_URING_PERM_MASK) { |
610 | audit_log_format(ab, fmt: " requested=\"%s\"" , |
611 | audit_uring_mask(mask: ad->request)); |
612 | if (ad->denied & AA_URING_PERM_MASK) { |
613 | audit_log_format(ab, fmt: " denied=\"%s\"" , |
614 | audit_uring_mask(mask: ad->denied)); |
615 | } |
616 | } |
617 | if (ad->uring.target) { |
618 | audit_log_format(ab, fmt: " tcontext=" ); |
619 | aa_label_xaudit(ab, labels_ns(ad->subj_label), |
620 | label: ad->uring.target, |
621 | FLAGS_NONE, GFP_ATOMIC); |
622 | } |
623 | } |
624 | |
625 | static int profile_uring(struct aa_profile *profile, u32 request, |
626 | struct aa_label *new, int cap, |
627 | struct apparmor_audit_data *ad) |
628 | { |
629 | unsigned int state; |
630 | struct aa_ruleset *rules; |
631 | int error = 0; |
632 | |
633 | AA_BUG(!profile); |
634 | |
635 | rules = list_first_entry(&profile->rules, typeof(*rules), list); |
636 | state = RULE_MEDIATES(rules, AA_CLASS_IO_URING); |
637 | if (state) { |
638 | struct aa_perms perms = { }; |
639 | |
640 | if (new) { |
641 | aa_label_match(profile, rules, label: new, state, |
642 | subns: false, request, perms: &perms); |
643 | } else { |
644 | perms = *aa_lookup_perms(policy: rules->policy, state); |
645 | } |
646 | aa_apply_modes_to_perms(profile, perms: &perms); |
647 | error = aa_check_perms(profile, perms: &perms, request, ad, |
648 | cb: audit_uring_cb); |
649 | } |
650 | |
651 | return error; |
652 | } |
653 | |
654 | /** |
655 | * apparmor_uring_override_creds - check the requested cred override |
656 | * @new: the target creds |
657 | * |
658 | * Check to see if the current task is allowed to override it's credentials |
659 | * to service an io_uring operation. |
660 | */ |
661 | static int apparmor_uring_override_creds(const struct cred *new) |
662 | { |
663 | struct aa_profile *profile; |
664 | struct aa_label *label; |
665 | int error; |
666 | DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_IO_URING, |
667 | OP_URING_OVERRIDE); |
668 | |
669 | ad.uring.target = cred_label(cred: new); |
670 | label = __begin_current_label_crit_section(); |
671 | error = fn_for_each(label, profile, |
672 | profile_uring(profile, AA_MAY_OVERRIDE_CRED, |
673 | cred_label(new), CAP_SYS_ADMIN, &ad)); |
674 | __end_current_label_crit_section(label); |
675 | |
676 | return error; |
677 | } |
678 | |
679 | /** |
680 | * apparmor_uring_sqpoll - check if a io_uring polling thread can be created |
681 | * |
682 | * Check to see if the current task is allowed to create a new io_uring |
683 | * kernel polling thread. |
684 | */ |
685 | static int apparmor_uring_sqpoll(void) |
686 | { |
687 | struct aa_profile *profile; |
688 | struct aa_label *label; |
689 | int error; |
690 | DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_IO_URING, |
691 | OP_URING_SQPOLL); |
692 | |
693 | label = __begin_current_label_crit_section(); |
694 | error = fn_for_each(label, profile, |
695 | profile_uring(profile, AA_MAY_CREATE_SQPOLL, |
696 | NULL, CAP_SYS_ADMIN, &ad)); |
697 | __end_current_label_crit_section(label); |
698 | |
699 | return error; |
700 | } |
701 | #endif /* CONFIG_IO_URING */ |
702 | |
703 | static int apparmor_sb_mount(const char *dev_name, const struct path *path, |
704 | const char *type, unsigned long flags, void *data) |
705 | { |
706 | struct aa_label *label; |
707 | int error = 0; |
708 | |
709 | /* Discard magic */ |
710 | if ((flags & MS_MGC_MSK) == MS_MGC_VAL) |
711 | flags &= ~MS_MGC_MSK; |
712 | |
713 | flags &= ~AA_MS_IGNORE_MASK; |
714 | |
715 | label = __begin_current_label_crit_section(); |
716 | if (!unconfined(label)) { |
717 | if (flags & MS_REMOUNT) |
718 | error = aa_remount(current_cred(), label, path, flags, |
719 | data); |
720 | else if (flags & MS_BIND) |
721 | error = aa_bind_mount(current_cred(), label, path, |
722 | old_name: dev_name, flags); |
723 | else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE | |
724 | MS_UNBINDABLE)) |
725 | error = aa_mount_change_type(current_cred(), label, |
726 | path, flags); |
727 | else if (flags & MS_MOVE) |
728 | error = aa_move_mount_old(current_cred(), label, path, |
729 | old_name: dev_name); |
730 | else |
731 | error = aa_new_mount(current_cred(), label, dev_name, |
732 | path, type, flags, data); |
733 | } |
734 | __end_current_label_crit_section(label); |
735 | |
736 | return error; |
737 | } |
738 | |
739 | static int apparmor_move_mount(const struct path *from_path, |
740 | const struct path *to_path) |
741 | { |
742 | struct aa_label *label; |
743 | int error = 0; |
744 | |
745 | label = __begin_current_label_crit_section(); |
746 | if (!unconfined(label)) |
747 | error = aa_move_mount(current_cred(), label, from_path, |
748 | to_path); |
749 | __end_current_label_crit_section(label); |
750 | |
751 | return error; |
752 | } |
753 | |
754 | static int apparmor_sb_umount(struct vfsmount *mnt, int flags) |
755 | { |
756 | struct aa_label *label; |
757 | int error = 0; |
758 | |
759 | label = __begin_current_label_crit_section(); |
760 | if (!unconfined(label)) |
761 | error = aa_umount(current_cred(), label, mnt, flags); |
762 | __end_current_label_crit_section(label); |
763 | |
764 | return error; |
765 | } |
766 | |
767 | static int apparmor_sb_pivotroot(const struct path *old_path, |
768 | const struct path *new_path) |
769 | { |
770 | struct aa_label *label; |
771 | int error = 0; |
772 | |
773 | label = aa_get_current_label(); |
774 | if (!unconfined(label)) |
775 | error = aa_pivotroot(current_cred(), label, old_path, new_path); |
776 | aa_put_label(l: label); |
777 | |
778 | return error; |
779 | } |
780 | |
781 | static int apparmor_getselfattr(unsigned int attr, struct lsm_ctx __user *lx, |
782 | u32 *size, u32 flags) |
783 | { |
784 | int error = -ENOENT; |
785 | struct aa_task_ctx *ctx = task_ctx(current); |
786 | struct aa_label *label = NULL; |
787 | char *value = NULL; |
788 | |
789 | switch (attr) { |
790 | case LSM_ATTR_CURRENT: |
791 | label = aa_get_newest_label(l: cred_label(current_cred())); |
792 | break; |
793 | case LSM_ATTR_PREV: |
794 | if (ctx->previous) |
795 | label = aa_get_newest_label(l: ctx->previous); |
796 | break; |
797 | case LSM_ATTR_EXEC: |
798 | if (ctx->onexec) |
799 | label = aa_get_newest_label(l: ctx->onexec); |
800 | break; |
801 | default: |
802 | error = -EOPNOTSUPP; |
803 | break; |
804 | } |
805 | |
806 | if (label) { |
807 | error = aa_getprocattr(label, string: &value, newline: false); |
808 | if (error > 0) |
809 | error = lsm_fill_user_ctx(uctx: lx, uctx_len: size, val: value, val_len: error, |
810 | LSM_ID_APPARMOR, flags: 0); |
811 | kfree(objp: value); |
812 | } |
813 | |
814 | aa_put_label(l: label); |
815 | |
816 | if (error < 0) |
817 | return error; |
818 | return 1; |
819 | } |
820 | |
821 | static int apparmor_getprocattr(struct task_struct *task, const char *name, |
822 | char **value) |
823 | { |
824 | int error = -ENOENT; |
825 | /* released below */ |
826 | const struct cred *cred = get_task_cred(task); |
827 | struct aa_task_ctx *ctx = task_ctx(current); |
828 | struct aa_label *label = NULL; |
829 | |
830 | if (strcmp(name, "current" ) == 0) |
831 | label = aa_get_newest_label(l: cred_label(cred)); |
832 | else if (strcmp(name, "prev" ) == 0 && ctx->previous) |
833 | label = aa_get_newest_label(l: ctx->previous); |
834 | else if (strcmp(name, "exec" ) == 0 && ctx->onexec) |
835 | label = aa_get_newest_label(l: ctx->onexec); |
836 | else |
837 | error = -EINVAL; |
838 | |
839 | if (label) |
840 | error = aa_getprocattr(label, string: value, newline: true); |
841 | |
842 | aa_put_label(l: label); |
843 | put_cred(cred); |
844 | |
845 | return error; |
846 | } |
847 | |
848 | static int do_setattr(u64 attr, void *value, size_t size) |
849 | { |
850 | char *command, *largs = NULL, *args = value; |
851 | size_t arg_size; |
852 | int error; |
853 | DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE, |
854 | OP_SETPROCATTR); |
855 | |
856 | if (size == 0) |
857 | return -EINVAL; |
858 | |
859 | /* AppArmor requires that the buffer must be null terminated atm */ |
860 | if (args[size - 1] != '\0') { |
861 | /* null terminate */ |
862 | largs = args = kmalloc(size: size + 1, GFP_KERNEL); |
863 | if (!args) |
864 | return -ENOMEM; |
865 | memcpy(args, value, size); |
866 | args[size] = '\0'; |
867 | } |
868 | |
869 | error = -EINVAL; |
870 | args = strim(args); |
871 | command = strsep(&args, " " ); |
872 | if (!args) |
873 | goto out; |
874 | args = skip_spaces(args); |
875 | if (!*args) |
876 | goto out; |
877 | |
878 | arg_size = size - (args - (largs ? largs : (char *) value)); |
879 | if (attr == LSM_ATTR_CURRENT) { |
880 | if (strcmp(command, "changehat" ) == 0) { |
881 | error = aa_setprocattr_changehat(args, size: arg_size, |
882 | AA_CHANGE_NOFLAGS); |
883 | } else if (strcmp(command, "permhat" ) == 0) { |
884 | error = aa_setprocattr_changehat(args, size: arg_size, |
885 | AA_CHANGE_TEST); |
886 | } else if (strcmp(command, "changeprofile" ) == 0) { |
887 | error = aa_change_profile(fqname: args, AA_CHANGE_NOFLAGS); |
888 | } else if (strcmp(command, "permprofile" ) == 0) { |
889 | error = aa_change_profile(fqname: args, AA_CHANGE_TEST); |
890 | } else if (strcmp(command, "stack" ) == 0) { |
891 | error = aa_change_profile(fqname: args, AA_CHANGE_STACK); |
892 | } else |
893 | goto fail; |
894 | } else if (attr == LSM_ATTR_EXEC) { |
895 | if (strcmp(command, "exec" ) == 0) |
896 | error = aa_change_profile(fqname: args, AA_CHANGE_ONEXEC); |
897 | else if (strcmp(command, "stack" ) == 0) |
898 | error = aa_change_profile(fqname: args, flags: (AA_CHANGE_ONEXEC | |
899 | AA_CHANGE_STACK)); |
900 | else |
901 | goto fail; |
902 | } else |
903 | /* only support the "current" and "exec" process attributes */ |
904 | goto fail; |
905 | |
906 | if (!error) |
907 | error = size; |
908 | out: |
909 | kfree(objp: largs); |
910 | return error; |
911 | |
912 | fail: |
913 | ad.subj_label = begin_current_label_crit_section(); |
914 | if (attr == LSM_ATTR_CURRENT) |
915 | ad.info = "current" ; |
916 | else if (attr == LSM_ATTR_EXEC) |
917 | ad.info = "exec" ; |
918 | else |
919 | ad.info = "invalid" ; |
920 | ad.error = error = -EINVAL; |
921 | aa_audit_msg(type: AUDIT_APPARMOR_DENIED, ad: &ad, NULL); |
922 | end_current_label_crit_section(label: ad.subj_label); |
923 | goto out; |
924 | } |
925 | |
926 | static int apparmor_setselfattr(unsigned int attr, struct lsm_ctx *ctx, |
927 | u32 size, u32 flags) |
928 | { |
929 | int rc; |
930 | |
931 | if (attr != LSM_ATTR_CURRENT && attr != LSM_ATTR_EXEC) |
932 | return -EOPNOTSUPP; |
933 | |
934 | rc = do_setattr(attr, value: ctx->ctx, size: ctx->ctx_len); |
935 | if (rc > 0) |
936 | return 0; |
937 | return rc; |
938 | } |
939 | |
940 | static int apparmor_setprocattr(const char *name, void *value, |
941 | size_t size) |
942 | { |
943 | int attr = lsm_name_to_attr(name); |
944 | |
945 | if (attr) |
946 | return do_setattr(attr, value, size); |
947 | return -EINVAL; |
948 | } |
949 | |
950 | /** |
951 | * apparmor_bprm_committing_creds - do task cleanup on committing new creds |
952 | * @bprm: binprm for the exec (NOT NULL) |
953 | */ |
954 | static void apparmor_bprm_committing_creds(const struct linux_binprm *bprm) |
955 | { |
956 | struct aa_label *label = aa_current_raw_label(); |
957 | struct aa_label *new_label = cred_label(cred: bprm->cred); |
958 | |
959 | /* bail out if unconfined or not changing profile */ |
960 | if ((new_label->proxy == label->proxy) || |
961 | (unconfined(new_label))) |
962 | return; |
963 | |
964 | aa_inherit_files(cred: bprm->cred, current->files); |
965 | |
966 | current->pdeath_signal = 0; |
967 | |
968 | /* reset soft limits and set hard limits for the new label */ |
969 | __aa_transition_rlimits(old: label, new: new_label); |
970 | } |
971 | |
972 | /** |
973 | * apparmor_bprm_committed_creds() - do cleanup after new creds committed |
974 | * @bprm: binprm for the exec (NOT NULL) |
975 | */ |
976 | static void apparmor_bprm_committed_creds(const struct linux_binprm *bprm) |
977 | { |
978 | /* clear out temporary/transitional state from the context */ |
979 | aa_clear_task_ctx_trans(ctx: task_ctx(current)); |
980 | |
981 | return; |
982 | } |
983 | |
984 | static void apparmor_current_getsecid_subj(u32 *secid) |
985 | { |
986 | struct aa_label *label = __begin_current_label_crit_section(); |
987 | *secid = label->secid; |
988 | __end_current_label_crit_section(label); |
989 | } |
990 | |
991 | static void apparmor_task_getsecid_obj(struct task_struct *p, u32 *secid) |
992 | { |
993 | struct aa_label *label = aa_get_task_label(task: p); |
994 | *secid = label->secid; |
995 | aa_put_label(l: label); |
996 | } |
997 | |
998 | static int apparmor_task_setrlimit(struct task_struct *task, |
999 | unsigned int resource, struct rlimit *new_rlim) |
1000 | { |
1001 | struct aa_label *label = __begin_current_label_crit_section(); |
1002 | int error = 0; |
1003 | |
1004 | if (!unconfined(label)) |
1005 | error = aa_task_setrlimit(current_cred(), label, task, |
1006 | resource, new_rlim); |
1007 | __end_current_label_crit_section(label); |
1008 | |
1009 | return error; |
1010 | } |
1011 | |
1012 | static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo *info, |
1013 | int sig, const struct cred *cred) |
1014 | { |
1015 | const struct cred *tc; |
1016 | struct aa_label *cl, *tl; |
1017 | int error; |
1018 | |
1019 | tc = get_task_cred(target); |
1020 | tl = aa_get_newest_cred_label(cred: tc); |
1021 | if (cred) { |
1022 | /* |
1023 | * Dealing with USB IO specific behavior |
1024 | */ |
1025 | cl = aa_get_newest_cred_label(cred); |
1026 | error = aa_may_signal(subj_cred: cred, sender: cl, target_cred: tc, target: tl, sig); |
1027 | aa_put_label(l: cl); |
1028 | } else { |
1029 | cl = __begin_current_label_crit_section(); |
1030 | error = aa_may_signal(current_cred(), sender: cl, target_cred: tc, target: tl, sig); |
1031 | __end_current_label_crit_section(cl); |
1032 | } |
1033 | aa_put_label(l: tl); |
1034 | put_cred(cred: tc); |
1035 | |
1036 | return error; |
1037 | } |
1038 | |
1039 | static int apparmor_userns_create(const struct cred *cred) |
1040 | { |
1041 | struct aa_label *label; |
1042 | struct aa_profile *profile; |
1043 | int error = 0; |
1044 | DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_TASK, AA_CLASS_NS, |
1045 | OP_USERNS_CREATE); |
1046 | |
1047 | ad.subj_cred = current_cred(); |
1048 | |
1049 | label = begin_current_label_crit_section(); |
1050 | if (!unconfined(label)) { |
1051 | error = fn_for_each(label, profile, |
1052 | aa_profile_ns_perm(profile, &ad, |
1053 | AA_USERNS_CREATE)); |
1054 | } |
1055 | end_current_label_crit_section(label); |
1056 | |
1057 | return error; |
1058 | } |
1059 | |
1060 | static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags) |
1061 | { |
1062 | struct aa_sk_ctx *ctx; |
1063 | |
1064 | ctx = kzalloc(size: sizeof(*ctx), flags); |
1065 | if (!ctx) |
1066 | return -ENOMEM; |
1067 | |
1068 | sk->sk_security = ctx; |
1069 | |
1070 | return 0; |
1071 | } |
1072 | |
1073 | static void apparmor_sk_free_security(struct sock *sk) |
1074 | { |
1075 | struct aa_sk_ctx *ctx = aa_sock(sk); |
1076 | |
1077 | sk->sk_security = NULL; |
1078 | aa_put_label(l: ctx->label); |
1079 | aa_put_label(l: ctx->peer); |
1080 | kfree(objp: ctx); |
1081 | } |
1082 | |
1083 | /** |
1084 | * apparmor_sk_clone_security - clone the sk_security field |
1085 | * @sk: sock to have security cloned |
1086 | * @newsk: sock getting clone |
1087 | */ |
1088 | static void apparmor_sk_clone_security(const struct sock *sk, |
1089 | struct sock *newsk) |
1090 | { |
1091 | struct aa_sk_ctx *ctx = aa_sock(sk); |
1092 | struct aa_sk_ctx *new = aa_sock(sk: newsk); |
1093 | |
1094 | if (new->label) |
1095 | aa_put_label(l: new->label); |
1096 | new->label = aa_get_label(l: ctx->label); |
1097 | |
1098 | if (new->peer) |
1099 | aa_put_label(l: new->peer); |
1100 | new->peer = aa_get_label(l: ctx->peer); |
1101 | } |
1102 | |
1103 | static int apparmor_socket_create(int family, int type, int protocol, int kern) |
1104 | { |
1105 | struct aa_label *label; |
1106 | int error = 0; |
1107 | |
1108 | AA_BUG(in_interrupt()); |
1109 | |
1110 | label = begin_current_label_crit_section(); |
1111 | if (!(kern || unconfined(label))) |
1112 | error = af_select(family, |
1113 | create_perm(label, family, type, protocol), |
1114 | aa_af_perm(current_cred(), label, |
1115 | OP_CREATE, AA_MAY_CREATE, |
1116 | family, type, protocol)); |
1117 | end_current_label_crit_section(label); |
1118 | |
1119 | return error; |
1120 | } |
1121 | |
1122 | /** |
1123 | * apparmor_socket_post_create - setup the per-socket security struct |
1124 | * @sock: socket that is being setup |
1125 | * @family: family of socket being created |
1126 | * @type: type of the socket |
1127 | * @ptotocol: protocol of the socket |
1128 | * @kern: socket is a special kernel socket |
1129 | * |
1130 | * Note: |
1131 | * - kernel sockets labeled kernel_t used to use unconfined |
1132 | * - socket may not have sk here if created with sock_create_lite or |
1133 | * sock_alloc. These should be accept cases which will be handled in |
1134 | * sock_graft. |
1135 | */ |
1136 | static int apparmor_socket_post_create(struct socket *sock, int family, |
1137 | int type, int protocol, int kern) |
1138 | { |
1139 | struct aa_label *label; |
1140 | |
1141 | if (kern) { |
1142 | label = aa_get_label(l: kernel_t); |
1143 | } else |
1144 | label = aa_get_current_label(); |
1145 | |
1146 | if (sock->sk) { |
1147 | struct aa_sk_ctx *ctx = aa_sock(sk: sock->sk); |
1148 | |
1149 | aa_put_label(l: ctx->label); |
1150 | ctx->label = aa_get_label(l: label); |
1151 | } |
1152 | aa_put_label(l: label); |
1153 | |
1154 | return 0; |
1155 | } |
1156 | |
1157 | static int apparmor_socket_bind(struct socket *sock, |
1158 | struct sockaddr *address, int addrlen) |
1159 | { |
1160 | AA_BUG(!sock); |
1161 | AA_BUG(!sock->sk); |
1162 | AA_BUG(!address); |
1163 | AA_BUG(in_interrupt()); |
1164 | |
1165 | return af_select(sock->sk->sk_family, |
1166 | bind_perm(sock, address, addrlen), |
1167 | aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk)); |
1168 | } |
1169 | |
1170 | static int apparmor_socket_connect(struct socket *sock, |
1171 | struct sockaddr *address, int addrlen) |
1172 | { |
1173 | AA_BUG(!sock); |
1174 | AA_BUG(!sock->sk); |
1175 | AA_BUG(!address); |
1176 | AA_BUG(in_interrupt()); |
1177 | |
1178 | return af_select(sock->sk->sk_family, |
1179 | connect_perm(sock, address, addrlen), |
1180 | aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk)); |
1181 | } |
1182 | |
1183 | static int apparmor_socket_listen(struct socket *sock, int backlog) |
1184 | { |
1185 | AA_BUG(!sock); |
1186 | AA_BUG(!sock->sk); |
1187 | AA_BUG(in_interrupt()); |
1188 | |
1189 | return af_select(sock->sk->sk_family, |
1190 | listen_perm(sock, backlog), |
1191 | aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk)); |
1192 | } |
1193 | |
1194 | /* |
1195 | * Note: while @newsock is created and has some information, the accept |
1196 | * has not been done. |
1197 | */ |
1198 | static int apparmor_socket_accept(struct socket *sock, struct socket *newsock) |
1199 | { |
1200 | AA_BUG(!sock); |
1201 | AA_BUG(!sock->sk); |
1202 | AA_BUG(!newsock); |
1203 | AA_BUG(in_interrupt()); |
1204 | |
1205 | return af_select(sock->sk->sk_family, |
1206 | accept_perm(sock, newsock), |
1207 | aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk)); |
1208 | } |
1209 | |
1210 | static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock, |
1211 | struct msghdr *msg, int size) |
1212 | { |
1213 | AA_BUG(!sock); |
1214 | AA_BUG(!sock->sk); |
1215 | AA_BUG(!msg); |
1216 | AA_BUG(in_interrupt()); |
1217 | |
1218 | return af_select(sock->sk->sk_family, |
1219 | msg_perm(op, request, sock, msg, size), |
1220 | aa_sk_perm(op, request, sock->sk)); |
1221 | } |
1222 | |
1223 | static int apparmor_socket_sendmsg(struct socket *sock, |
1224 | struct msghdr *msg, int size) |
1225 | { |
1226 | return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size); |
1227 | } |
1228 | |
1229 | static int apparmor_socket_recvmsg(struct socket *sock, |
1230 | struct msghdr *msg, int size, int flags) |
1231 | { |
1232 | return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size); |
1233 | } |
1234 | |
1235 | /* revaliation, get/set attr, shutdown */ |
1236 | static int aa_sock_perm(const char *op, u32 request, struct socket *sock) |
1237 | { |
1238 | AA_BUG(!sock); |
1239 | AA_BUG(!sock->sk); |
1240 | AA_BUG(in_interrupt()); |
1241 | |
1242 | return af_select(sock->sk->sk_family, |
1243 | sock_perm(op, request, sock), |
1244 | aa_sk_perm(op, request, sock->sk)); |
1245 | } |
1246 | |
1247 | static int apparmor_socket_getsockname(struct socket *sock) |
1248 | { |
1249 | return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock); |
1250 | } |
1251 | |
1252 | static int apparmor_socket_getpeername(struct socket *sock) |
1253 | { |
1254 | return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock); |
1255 | } |
1256 | |
1257 | /* revaliation, get/set attr, opt */ |
1258 | static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock, |
1259 | int level, int optname) |
1260 | { |
1261 | AA_BUG(!sock); |
1262 | AA_BUG(!sock->sk); |
1263 | AA_BUG(in_interrupt()); |
1264 | |
1265 | return af_select(sock->sk->sk_family, |
1266 | opt_perm(op, request, sock, level, optname), |
1267 | aa_sk_perm(op, request, sock->sk)); |
1268 | } |
1269 | |
1270 | static int apparmor_socket_getsockopt(struct socket *sock, int level, |
1271 | int optname) |
1272 | { |
1273 | return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock, |
1274 | level, optname); |
1275 | } |
1276 | |
1277 | static int apparmor_socket_setsockopt(struct socket *sock, int level, |
1278 | int optname) |
1279 | { |
1280 | return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock, |
1281 | level, optname); |
1282 | } |
1283 | |
1284 | static int apparmor_socket_shutdown(struct socket *sock, int how) |
1285 | { |
1286 | return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock); |
1287 | } |
1288 | |
1289 | #ifdef CONFIG_NETWORK_SECMARK |
1290 | /** |
1291 | * apparmor_socket_sock_rcv_skb - check perms before associating skb to sk |
1292 | * @sk: sk to associate @skb with |
1293 | * @skb: skb to check for perms |
1294 | * |
1295 | * Note: can not sleep may be called with locks held |
1296 | * |
1297 | * dont want protocol specific in __skb_recv_datagram() |
1298 | * to deny an incoming connection socket_sock_rcv_skb() |
1299 | */ |
1300 | static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) |
1301 | { |
1302 | struct aa_sk_ctx *ctx = aa_sock(sk); |
1303 | |
1304 | if (!skb->secmark) |
1305 | return 0; |
1306 | |
1307 | return apparmor_secmark_check(label: ctx->label, OP_RECVMSG, AA_MAY_RECEIVE, |
1308 | secid: skb->secmark, sk); |
1309 | } |
1310 | #endif |
1311 | |
1312 | |
1313 | static struct aa_label *sk_peer_label(struct sock *sk) |
1314 | { |
1315 | struct aa_sk_ctx *ctx = aa_sock(sk); |
1316 | |
1317 | if (ctx->peer) |
1318 | return ctx->peer; |
1319 | |
1320 | return ERR_PTR(error: -ENOPROTOOPT); |
1321 | } |
1322 | |
1323 | /** |
1324 | * apparmor_socket_getpeersec_stream - get security context of peer |
1325 | * @sock: socket that we are trying to get the peer context of |
1326 | * @optval: output - buffer to copy peer name to |
1327 | * @optlen: output - size of copied name in @optval |
1328 | * @len: size of @optval buffer |
1329 | * Returns: 0 on success, -errno of failure |
1330 | * |
1331 | * Note: for tcp only valid if using ipsec or cipso on lan |
1332 | */ |
1333 | static int apparmor_socket_getpeersec_stream(struct socket *sock, |
1334 | sockptr_t optval, sockptr_t optlen, |
1335 | unsigned int len) |
1336 | { |
1337 | char *name = NULL; |
1338 | int slen, error = 0; |
1339 | struct aa_label *label; |
1340 | struct aa_label *peer; |
1341 | |
1342 | label = begin_current_label_crit_section(); |
1343 | peer = sk_peer_label(sk: sock->sk); |
1344 | if (IS_ERR(ptr: peer)) { |
1345 | error = PTR_ERR(ptr: peer); |
1346 | goto done; |
1347 | } |
1348 | slen = aa_label_asxprint(strp: &name, labels_ns(label), label: peer, |
1349 | FLAG_SHOW_MODE | FLAG_VIEW_SUBNS | |
1350 | FLAG_HIDDEN_UNCONFINED, GFP_KERNEL); |
1351 | /* don't include terminating \0 in slen, it breaks some apps */ |
1352 | if (slen < 0) { |
1353 | error = -ENOMEM; |
1354 | goto done; |
1355 | } |
1356 | if (slen > len) { |
1357 | error = -ERANGE; |
1358 | goto done_len; |
1359 | } |
1360 | |
1361 | if (copy_to_sockptr(dst: optval, src: name, size: slen)) |
1362 | error = -EFAULT; |
1363 | done_len: |
1364 | if (copy_to_sockptr(dst: optlen, src: &slen, size: sizeof(slen))) |
1365 | error = -EFAULT; |
1366 | done: |
1367 | end_current_label_crit_section(label); |
1368 | kfree(objp: name); |
1369 | return error; |
1370 | } |
1371 | |
1372 | /** |
1373 | * apparmor_socket_getpeersec_dgram - get security label of packet |
1374 | * @sock: the peer socket |
1375 | * @skb: packet data |
1376 | * @secid: pointer to where to put the secid of the packet |
1377 | * |
1378 | * Sets the netlabel socket state on sk from parent |
1379 | */ |
1380 | static int apparmor_socket_getpeersec_dgram(struct socket *sock, |
1381 | struct sk_buff *skb, u32 *secid) |
1382 | |
1383 | { |
1384 | /* TODO: requires secid support */ |
1385 | return -ENOPROTOOPT; |
1386 | } |
1387 | |
1388 | /** |
1389 | * apparmor_sock_graft - Initialize newly created socket |
1390 | * @sk: child sock |
1391 | * @parent: parent socket |
1392 | * |
1393 | * Note: could set off of SOCK_CTX(parent) but need to track inode and we can |
1394 | * just set sk security information off of current creating process label |
1395 | * Labeling of sk for accept case - probably should be sock based |
1396 | * instead of task, because of the case where an implicitly labeled |
1397 | * socket is shared by different tasks. |
1398 | */ |
1399 | static void apparmor_sock_graft(struct sock *sk, struct socket *parent) |
1400 | { |
1401 | struct aa_sk_ctx *ctx = aa_sock(sk); |
1402 | |
1403 | if (!ctx->label) |
1404 | ctx->label = aa_get_current_label(); |
1405 | } |
1406 | |
1407 | #ifdef CONFIG_NETWORK_SECMARK |
1408 | static int apparmor_inet_conn_request(const struct sock *sk, struct sk_buff *skb, |
1409 | struct request_sock *req) |
1410 | { |
1411 | struct aa_sk_ctx *ctx = aa_sock(sk); |
1412 | |
1413 | if (!skb->secmark) |
1414 | return 0; |
1415 | |
1416 | return apparmor_secmark_check(label: ctx->label, OP_CONNECT, AA_MAY_CONNECT, |
1417 | secid: skb->secmark, sk); |
1418 | } |
1419 | #endif |
1420 | |
1421 | /* |
1422 | * The cred blob is a pointer to, not an instance of, an aa_label. |
1423 | */ |
1424 | struct lsm_blob_sizes apparmor_blob_sizes __ro_after_init = { |
1425 | .lbs_cred = sizeof(struct aa_label *), |
1426 | .lbs_file = sizeof(struct aa_file_ctx), |
1427 | .lbs_task = sizeof(struct aa_task_ctx), |
1428 | }; |
1429 | |
1430 | static const struct lsm_id apparmor_lsmid = { |
1431 | .name = "apparmor" , |
1432 | .id = LSM_ID_APPARMOR, |
1433 | }; |
1434 | |
1435 | static struct security_hook_list apparmor_hooks[] __ro_after_init = { |
1436 | LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check), |
1437 | LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme), |
1438 | LSM_HOOK_INIT(capget, apparmor_capget), |
1439 | LSM_HOOK_INIT(capable, apparmor_capable), |
1440 | |
1441 | LSM_HOOK_INIT(move_mount, apparmor_move_mount), |
1442 | LSM_HOOK_INIT(sb_mount, apparmor_sb_mount), |
1443 | LSM_HOOK_INIT(sb_umount, apparmor_sb_umount), |
1444 | LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot), |
1445 | |
1446 | LSM_HOOK_INIT(path_link, apparmor_path_link), |
1447 | LSM_HOOK_INIT(path_unlink, apparmor_path_unlink), |
1448 | LSM_HOOK_INIT(path_symlink, apparmor_path_symlink), |
1449 | LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir), |
1450 | LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir), |
1451 | LSM_HOOK_INIT(path_mknod, apparmor_path_mknod), |
1452 | LSM_HOOK_INIT(path_rename, apparmor_path_rename), |
1453 | LSM_HOOK_INIT(path_chmod, apparmor_path_chmod), |
1454 | LSM_HOOK_INIT(path_chown, apparmor_path_chown), |
1455 | LSM_HOOK_INIT(path_truncate, apparmor_path_truncate), |
1456 | LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr), |
1457 | |
1458 | LSM_HOOK_INIT(file_open, apparmor_file_open), |
1459 | LSM_HOOK_INIT(file_receive, apparmor_file_receive), |
1460 | LSM_HOOK_INIT(file_permission, apparmor_file_permission), |
1461 | LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security), |
1462 | LSM_HOOK_INIT(file_free_security, apparmor_file_free_security), |
1463 | LSM_HOOK_INIT(mmap_file, apparmor_mmap_file), |
1464 | LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect), |
1465 | LSM_HOOK_INIT(file_lock, apparmor_file_lock), |
1466 | LSM_HOOK_INIT(file_truncate, apparmor_file_truncate), |
1467 | |
1468 | LSM_HOOK_INIT(getselfattr, apparmor_getselfattr), |
1469 | LSM_HOOK_INIT(setselfattr, apparmor_setselfattr), |
1470 | LSM_HOOK_INIT(getprocattr, apparmor_getprocattr), |
1471 | LSM_HOOK_INIT(setprocattr, apparmor_setprocattr), |
1472 | |
1473 | LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security), |
1474 | LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security), |
1475 | LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security), |
1476 | |
1477 | LSM_HOOK_INIT(socket_create, apparmor_socket_create), |
1478 | LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create), |
1479 | LSM_HOOK_INIT(socket_bind, apparmor_socket_bind), |
1480 | LSM_HOOK_INIT(socket_connect, apparmor_socket_connect), |
1481 | LSM_HOOK_INIT(socket_listen, apparmor_socket_listen), |
1482 | LSM_HOOK_INIT(socket_accept, apparmor_socket_accept), |
1483 | LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg), |
1484 | LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg), |
1485 | LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname), |
1486 | LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername), |
1487 | LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt), |
1488 | LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt), |
1489 | LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown), |
1490 | #ifdef CONFIG_NETWORK_SECMARK |
1491 | LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb), |
1492 | #endif |
1493 | LSM_HOOK_INIT(socket_getpeersec_stream, |
1494 | apparmor_socket_getpeersec_stream), |
1495 | LSM_HOOK_INIT(socket_getpeersec_dgram, |
1496 | apparmor_socket_getpeersec_dgram), |
1497 | LSM_HOOK_INIT(sock_graft, apparmor_sock_graft), |
1498 | #ifdef CONFIG_NETWORK_SECMARK |
1499 | LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request), |
1500 | #endif |
1501 | |
1502 | LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank), |
1503 | LSM_HOOK_INIT(cred_free, apparmor_cred_free), |
1504 | LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare), |
1505 | LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer), |
1506 | |
1507 | LSM_HOOK_INIT(bprm_creds_for_exec, apparmor_bprm_creds_for_exec), |
1508 | LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds), |
1509 | LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds), |
1510 | |
1511 | LSM_HOOK_INIT(task_free, apparmor_task_free), |
1512 | LSM_HOOK_INIT(task_alloc, apparmor_task_alloc), |
1513 | LSM_HOOK_INIT(current_getsecid_subj, apparmor_current_getsecid_subj), |
1514 | LSM_HOOK_INIT(task_getsecid_obj, apparmor_task_getsecid_obj), |
1515 | LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit), |
1516 | LSM_HOOK_INIT(task_kill, apparmor_task_kill), |
1517 | LSM_HOOK_INIT(userns_create, apparmor_userns_create), |
1518 | |
1519 | #ifdef CONFIG_AUDIT |
1520 | LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init), |
1521 | LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known), |
1522 | LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match), |
1523 | LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free), |
1524 | #endif |
1525 | |
1526 | LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx), |
1527 | LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid), |
1528 | LSM_HOOK_INIT(release_secctx, apparmor_release_secctx), |
1529 | |
1530 | #ifdef CONFIG_IO_URING |
1531 | LSM_HOOK_INIT(uring_override_creds, apparmor_uring_override_creds), |
1532 | LSM_HOOK_INIT(uring_sqpoll, apparmor_uring_sqpoll), |
1533 | #endif |
1534 | }; |
1535 | |
1536 | /* |
1537 | * AppArmor sysfs module parameters |
1538 | */ |
1539 | |
1540 | static int param_set_aabool(const char *val, const struct kernel_param *kp); |
1541 | static int param_get_aabool(char *buffer, const struct kernel_param *kp); |
1542 | #define param_check_aabool param_check_bool |
1543 | static const struct kernel_param_ops param_ops_aabool = { |
1544 | .flags = KERNEL_PARAM_OPS_FL_NOARG, |
1545 | .set = param_set_aabool, |
1546 | .get = param_get_aabool |
1547 | }; |
1548 | |
1549 | static int param_set_aauint(const char *val, const struct kernel_param *kp); |
1550 | static int param_get_aauint(char *buffer, const struct kernel_param *kp); |
1551 | #define param_check_aauint param_check_uint |
1552 | static const struct kernel_param_ops param_ops_aauint = { |
1553 | .set = param_set_aauint, |
1554 | .get = param_get_aauint |
1555 | }; |
1556 | |
1557 | static int param_set_aacompressionlevel(const char *val, |
1558 | const struct kernel_param *kp); |
1559 | static int param_get_aacompressionlevel(char *buffer, |
1560 | const struct kernel_param *kp); |
1561 | #define param_check_aacompressionlevel param_check_int |
1562 | static const struct kernel_param_ops param_ops_aacompressionlevel = { |
1563 | .set = param_set_aacompressionlevel, |
1564 | .get = param_get_aacompressionlevel |
1565 | }; |
1566 | |
1567 | static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp); |
1568 | static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp); |
1569 | #define param_check_aalockpolicy param_check_bool |
1570 | static const struct kernel_param_ops param_ops_aalockpolicy = { |
1571 | .flags = KERNEL_PARAM_OPS_FL_NOARG, |
1572 | .set = param_set_aalockpolicy, |
1573 | .get = param_get_aalockpolicy |
1574 | }; |
1575 | |
1576 | static int param_set_audit(const char *val, const struct kernel_param *kp); |
1577 | static int param_get_audit(char *buffer, const struct kernel_param *kp); |
1578 | |
1579 | static int param_set_mode(const char *val, const struct kernel_param *kp); |
1580 | static int param_get_mode(char *buffer, const struct kernel_param *kp); |
1581 | |
1582 | /* Flag values, also controllable via /sys/module/apparmor/parameters |
1583 | * We define special types as we want to do additional mediation. |
1584 | */ |
1585 | |
1586 | /* AppArmor global enforcement switch - complain, enforce, kill */ |
1587 | enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE; |
1588 | module_param_call(mode, param_set_mode, param_get_mode, |
1589 | &aa_g_profile_mode, S_IRUSR | S_IWUSR); |
1590 | |
1591 | /* whether policy verification hashing is enabled */ |
1592 | bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT); |
1593 | #ifdef CONFIG_SECURITY_APPARMOR_HASH |
1594 | module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR); |
1595 | #endif |
1596 | |
1597 | /* whether policy exactly as loaded is retained for debug and checkpointing */ |
1598 | bool aa_g_export_binary = IS_ENABLED(CONFIG_SECURITY_APPARMOR_EXPORT_BINARY); |
1599 | #ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY |
1600 | module_param_named(export_binary, aa_g_export_binary, aabool, 0600); |
1601 | #endif |
1602 | |
1603 | /* policy loaddata compression level */ |
1604 | int aa_g_rawdata_compression_level = AA_DEFAULT_CLEVEL; |
1605 | module_param_named(rawdata_compression_level, aa_g_rawdata_compression_level, |
1606 | aacompressionlevel, 0400); |
1607 | |
1608 | /* Debug mode */ |
1609 | bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES); |
1610 | module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR); |
1611 | |
1612 | /* Audit mode */ |
1613 | enum audit_mode aa_g_audit; |
1614 | module_param_call(audit, param_set_audit, param_get_audit, |
1615 | &aa_g_audit, S_IRUSR | S_IWUSR); |
1616 | |
1617 | /* Determines if audit header is included in audited messages. This |
1618 | * provides more context if the audit daemon is not running |
1619 | */ |
1620 | bool = true; |
1621 | module_param_named(audit_header, aa_g_audit_header, aabool, |
1622 | S_IRUSR | S_IWUSR); |
1623 | |
1624 | /* lock out loading/removal of policy |
1625 | * TODO: add in at boot loading of policy, which is the only way to |
1626 | * load policy, if lock_policy is set |
1627 | */ |
1628 | bool aa_g_lock_policy; |
1629 | module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy, |
1630 | S_IRUSR | S_IWUSR); |
1631 | |
1632 | /* Syscall logging mode */ |
1633 | bool aa_g_logsyscall; |
1634 | module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR); |
1635 | |
1636 | /* Maximum pathname length before accesses will start getting rejected */ |
1637 | unsigned int aa_g_path_max = 2 * PATH_MAX; |
1638 | module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR); |
1639 | |
1640 | /* Determines how paranoid loading of policy is and how much verification |
1641 | * on the loaded policy is done. |
1642 | * DEPRECATED: read only as strict checking of load is always done now |
1643 | * that none root users (user namespaces) can load policy. |
1644 | */ |
1645 | bool aa_g_paranoid_load = IS_ENABLED(CONFIG_SECURITY_APPARMOR_PARANOID_LOAD); |
1646 | module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO); |
1647 | |
1648 | static int param_get_aaintbool(char *buffer, const struct kernel_param *kp); |
1649 | static int param_set_aaintbool(const char *val, const struct kernel_param *kp); |
1650 | #define param_check_aaintbool param_check_int |
1651 | static const struct kernel_param_ops param_ops_aaintbool = { |
1652 | .set = param_set_aaintbool, |
1653 | .get = param_get_aaintbool |
1654 | }; |
1655 | /* Boot time disable flag */ |
1656 | static int apparmor_enabled __ro_after_init = 1; |
1657 | module_param_named(enabled, apparmor_enabled, aaintbool, 0444); |
1658 | |
1659 | static int __init apparmor_enabled_setup(char *str) |
1660 | { |
1661 | unsigned long enabled; |
1662 | int error = kstrtoul(s: str, base: 0, res: &enabled); |
1663 | if (!error) |
1664 | apparmor_enabled = enabled ? 1 : 0; |
1665 | return 1; |
1666 | } |
1667 | |
1668 | __setup("apparmor=" , apparmor_enabled_setup); |
1669 | |
1670 | /* set global flag turning off the ability to load policy */ |
1671 | static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp) |
1672 | { |
1673 | if (!apparmor_enabled) |
1674 | return -EINVAL; |
1675 | if (apparmor_initialized && !aa_current_policy_admin_capable(NULL)) |
1676 | return -EPERM; |
1677 | return param_set_bool(val, kp); |
1678 | } |
1679 | |
1680 | static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp) |
1681 | { |
1682 | if (!apparmor_enabled) |
1683 | return -EINVAL; |
1684 | if (apparmor_initialized && !aa_current_policy_view_capable(NULL)) |
1685 | return -EPERM; |
1686 | return param_get_bool(buffer, kp); |
1687 | } |
1688 | |
1689 | static int param_set_aabool(const char *val, const struct kernel_param *kp) |
1690 | { |
1691 | if (!apparmor_enabled) |
1692 | return -EINVAL; |
1693 | if (apparmor_initialized && !aa_current_policy_admin_capable(NULL)) |
1694 | return -EPERM; |
1695 | return param_set_bool(val, kp); |
1696 | } |
1697 | |
1698 | static int param_get_aabool(char *buffer, const struct kernel_param *kp) |
1699 | { |
1700 | if (!apparmor_enabled) |
1701 | return -EINVAL; |
1702 | if (apparmor_initialized && !aa_current_policy_view_capable(NULL)) |
1703 | return -EPERM; |
1704 | return param_get_bool(buffer, kp); |
1705 | } |
1706 | |
1707 | static int param_set_aauint(const char *val, const struct kernel_param *kp) |
1708 | { |
1709 | int error; |
1710 | |
1711 | if (!apparmor_enabled) |
1712 | return -EINVAL; |
1713 | /* file is ro but enforce 2nd line check */ |
1714 | if (apparmor_initialized) |
1715 | return -EPERM; |
1716 | |
1717 | error = param_set_uint(val, kp); |
1718 | aa_g_path_max = max_t(uint32_t, aa_g_path_max, sizeof(union aa_buffer)); |
1719 | pr_info("AppArmor: buffer size set to %d bytes\n" , aa_g_path_max); |
1720 | |
1721 | return error; |
1722 | } |
1723 | |
1724 | static int param_get_aauint(char *buffer, const struct kernel_param *kp) |
1725 | { |
1726 | if (!apparmor_enabled) |
1727 | return -EINVAL; |
1728 | if (apparmor_initialized && !aa_current_policy_view_capable(NULL)) |
1729 | return -EPERM; |
1730 | return param_get_uint(buffer, kp); |
1731 | } |
1732 | |
1733 | /* Can only be set before AppArmor is initialized (i.e. on boot cmdline). */ |
1734 | static int param_set_aaintbool(const char *val, const struct kernel_param *kp) |
1735 | { |
1736 | struct kernel_param kp_local; |
1737 | bool value; |
1738 | int error; |
1739 | |
1740 | if (apparmor_initialized) |
1741 | return -EPERM; |
1742 | |
1743 | /* Create local copy, with arg pointing to bool type. */ |
1744 | value = !!*((int *)kp->arg); |
1745 | memcpy(&kp_local, kp, sizeof(kp_local)); |
1746 | kp_local.arg = &value; |
1747 | |
1748 | error = param_set_bool(val, kp: &kp_local); |
1749 | if (!error) |
1750 | *((int *)kp->arg) = *((bool *)kp_local.arg); |
1751 | return error; |
1752 | } |
1753 | |
1754 | /* |
1755 | * To avoid changing /sys/module/apparmor/parameters/enabled from Y/N to |
1756 | * 1/0, this converts the "int that is actually bool" back to bool for |
1757 | * display in the /sys filesystem, while keeping it "int" for the LSM |
1758 | * infrastructure. |
1759 | */ |
1760 | static int param_get_aaintbool(char *buffer, const struct kernel_param *kp) |
1761 | { |
1762 | struct kernel_param kp_local; |
1763 | bool value; |
1764 | |
1765 | /* Create local copy, with arg pointing to bool type. */ |
1766 | value = !!*((int *)kp->arg); |
1767 | memcpy(&kp_local, kp, sizeof(kp_local)); |
1768 | kp_local.arg = &value; |
1769 | |
1770 | return param_get_bool(buffer, kp: &kp_local); |
1771 | } |
1772 | |
1773 | static int param_set_aacompressionlevel(const char *val, |
1774 | const struct kernel_param *kp) |
1775 | { |
1776 | int error; |
1777 | |
1778 | if (!apparmor_enabled) |
1779 | return -EINVAL; |
1780 | if (apparmor_initialized) |
1781 | return -EPERM; |
1782 | |
1783 | error = param_set_int(val, kp); |
1784 | |
1785 | aa_g_rawdata_compression_level = clamp(aa_g_rawdata_compression_level, |
1786 | AA_MIN_CLEVEL, AA_MAX_CLEVEL); |
1787 | pr_info("AppArmor: policy rawdata compression level set to %d\n" , |
1788 | aa_g_rawdata_compression_level); |
1789 | |
1790 | return error; |
1791 | } |
1792 | |
1793 | static int param_get_aacompressionlevel(char *buffer, |
1794 | const struct kernel_param *kp) |
1795 | { |
1796 | if (!apparmor_enabled) |
1797 | return -EINVAL; |
1798 | if (apparmor_initialized && !aa_current_policy_view_capable(NULL)) |
1799 | return -EPERM; |
1800 | return param_get_int(buffer, kp); |
1801 | } |
1802 | |
1803 | static int param_get_audit(char *buffer, const struct kernel_param *kp) |
1804 | { |
1805 | if (!apparmor_enabled) |
1806 | return -EINVAL; |
1807 | if (apparmor_initialized && !aa_current_policy_view_capable(NULL)) |
1808 | return -EPERM; |
1809 | return sprintf(buf: buffer, fmt: "%s" , audit_mode_names[aa_g_audit]); |
1810 | } |
1811 | |
1812 | static int param_set_audit(const char *val, const struct kernel_param *kp) |
1813 | { |
1814 | int i; |
1815 | |
1816 | if (!apparmor_enabled) |
1817 | return -EINVAL; |
1818 | if (!val) |
1819 | return -EINVAL; |
1820 | if (apparmor_initialized && !aa_current_policy_admin_capable(NULL)) |
1821 | return -EPERM; |
1822 | |
1823 | i = match_string(array: audit_mode_names, AUDIT_MAX_INDEX, string: val); |
1824 | if (i < 0) |
1825 | return -EINVAL; |
1826 | |
1827 | aa_g_audit = i; |
1828 | return 0; |
1829 | } |
1830 | |
1831 | static int param_get_mode(char *buffer, const struct kernel_param *kp) |
1832 | { |
1833 | if (!apparmor_enabled) |
1834 | return -EINVAL; |
1835 | if (apparmor_initialized && !aa_current_policy_view_capable(NULL)) |
1836 | return -EPERM; |
1837 | |
1838 | return sprintf(buf: buffer, fmt: "%s" , aa_profile_mode_names[aa_g_profile_mode]); |
1839 | } |
1840 | |
1841 | static int param_set_mode(const char *val, const struct kernel_param *kp) |
1842 | { |
1843 | int i; |
1844 | |
1845 | if (!apparmor_enabled) |
1846 | return -EINVAL; |
1847 | if (!val) |
1848 | return -EINVAL; |
1849 | if (apparmor_initialized && !aa_current_policy_admin_capable(NULL)) |
1850 | return -EPERM; |
1851 | |
1852 | i = match_string(array: aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX, |
1853 | string: val); |
1854 | if (i < 0) |
1855 | return -EINVAL; |
1856 | |
1857 | aa_g_profile_mode = i; |
1858 | return 0; |
1859 | } |
1860 | |
1861 | char *aa_get_buffer(bool in_atomic) |
1862 | { |
1863 | union aa_buffer *aa_buf; |
1864 | struct aa_local_cache *cache; |
1865 | bool try_again = true; |
1866 | gfp_t flags = (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN); |
1867 | |
1868 | /* use per cpu cached buffers first */ |
1869 | cache = get_cpu_ptr(&aa_local_buffers); |
1870 | if (!list_empty(head: &cache->head)) { |
1871 | aa_buf = list_first_entry(&cache->head, union aa_buffer, list); |
1872 | list_del(entry: &aa_buf->list); |
1873 | cache->hold--; |
1874 | cache->count--; |
1875 | put_cpu_ptr(&aa_local_buffers); |
1876 | return &aa_buf->buffer[0]; |
1877 | } |
1878 | put_cpu_ptr(&aa_local_buffers); |
1879 | |
1880 | if (!spin_trylock(lock: &aa_buffers_lock)) { |
1881 | cache = get_cpu_ptr(&aa_local_buffers); |
1882 | cache->hold += 1; |
1883 | put_cpu_ptr(&aa_local_buffers); |
1884 | spin_lock(lock: &aa_buffers_lock); |
1885 | } else { |
1886 | cache = get_cpu_ptr(&aa_local_buffers); |
1887 | put_cpu_ptr(&aa_local_buffers); |
1888 | } |
1889 | retry: |
1890 | if (buffer_count > reserve_count || |
1891 | (in_atomic && !list_empty(head: &aa_global_buffers))) { |
1892 | aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer, |
1893 | list); |
1894 | list_del(entry: &aa_buf->list); |
1895 | buffer_count--; |
1896 | spin_unlock(lock: &aa_buffers_lock); |
1897 | return aa_buf->buffer; |
1898 | } |
1899 | if (in_atomic) { |
1900 | /* |
1901 | * out of reserve buffers and in atomic context so increase |
1902 | * how many buffers to keep in reserve |
1903 | */ |
1904 | reserve_count++; |
1905 | flags = GFP_ATOMIC; |
1906 | } |
1907 | spin_unlock(lock: &aa_buffers_lock); |
1908 | |
1909 | if (!in_atomic) |
1910 | might_sleep(); |
1911 | aa_buf = kmalloc(size: aa_g_path_max, flags); |
1912 | if (!aa_buf) { |
1913 | if (try_again) { |
1914 | try_again = false; |
1915 | spin_lock(lock: &aa_buffers_lock); |
1916 | goto retry; |
1917 | } |
1918 | pr_warn_once("AppArmor: Failed to allocate a memory buffer.\n" ); |
1919 | return NULL; |
1920 | } |
1921 | return aa_buf->buffer; |
1922 | } |
1923 | |
1924 | void aa_put_buffer(char *buf) |
1925 | { |
1926 | union aa_buffer *aa_buf; |
1927 | struct aa_local_cache *cache; |
1928 | |
1929 | if (!buf) |
1930 | return; |
1931 | aa_buf = container_of(buf, union aa_buffer, buffer[0]); |
1932 | |
1933 | cache = get_cpu_ptr(&aa_local_buffers); |
1934 | if (!cache->hold) { |
1935 | put_cpu_ptr(&aa_local_buffers); |
1936 | |
1937 | if (spin_trylock(lock: &aa_buffers_lock)) { |
1938 | /* put back on global list */ |
1939 | list_add(new: &aa_buf->list, head: &aa_global_buffers); |
1940 | buffer_count++; |
1941 | spin_unlock(lock: &aa_buffers_lock); |
1942 | cache = get_cpu_ptr(&aa_local_buffers); |
1943 | put_cpu_ptr(&aa_local_buffers); |
1944 | return; |
1945 | } |
1946 | /* contention on global list, fallback to percpu */ |
1947 | cache = get_cpu_ptr(&aa_local_buffers); |
1948 | cache->hold += 1; |
1949 | } |
1950 | |
1951 | /* cache in percpu list */ |
1952 | list_add(new: &aa_buf->list, head: &cache->head); |
1953 | cache->count++; |
1954 | put_cpu_ptr(&aa_local_buffers); |
1955 | } |
1956 | |
1957 | /* |
1958 | * AppArmor init functions |
1959 | */ |
1960 | |
1961 | /** |
1962 | * set_init_ctx - set a task context and profile on the first task. |
1963 | * |
1964 | * TODO: allow setting an alternate profile than unconfined |
1965 | */ |
1966 | static int __init set_init_ctx(void) |
1967 | { |
1968 | struct cred *cred = (__force struct cred *)current->real_cred; |
1969 | |
1970 | set_cred_label(cred, label: aa_get_label(ns_unconfined(root_ns))); |
1971 | |
1972 | return 0; |
1973 | } |
1974 | |
1975 | static void destroy_buffers(void) |
1976 | { |
1977 | union aa_buffer *aa_buf; |
1978 | |
1979 | spin_lock(lock: &aa_buffers_lock); |
1980 | while (!list_empty(head: &aa_global_buffers)) { |
1981 | aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer, |
1982 | list); |
1983 | list_del(entry: &aa_buf->list); |
1984 | spin_unlock(lock: &aa_buffers_lock); |
1985 | kfree(objp: aa_buf); |
1986 | spin_lock(lock: &aa_buffers_lock); |
1987 | } |
1988 | spin_unlock(lock: &aa_buffers_lock); |
1989 | } |
1990 | |
1991 | static int __init alloc_buffers(void) |
1992 | { |
1993 | union aa_buffer *aa_buf; |
1994 | int i, num; |
1995 | |
1996 | /* |
1997 | * per cpu set of cached allocated buffers used to help reduce |
1998 | * lock contention |
1999 | */ |
2000 | for_each_possible_cpu(i) { |
2001 | per_cpu(aa_local_buffers, i).hold = 0; |
2002 | per_cpu(aa_local_buffers, i).count = 0; |
2003 | INIT_LIST_HEAD(list: &per_cpu(aa_local_buffers, i).head); |
2004 | } |
2005 | /* |
2006 | * A function may require two buffers at once. Usually the buffers are |
2007 | * used for a short period of time and are shared. On UP kernel buffers |
2008 | * two should be enough, with more CPUs it is possible that more |
2009 | * buffers will be used simultaneously. The preallocated pool may grow. |
2010 | * This preallocation has also the side-effect that AppArmor will be |
2011 | * disabled early at boot if aa_g_path_max is extremly high. |
2012 | */ |
2013 | if (num_online_cpus() > 1) |
2014 | num = 4 + RESERVE_COUNT; |
2015 | else |
2016 | num = 2 + RESERVE_COUNT; |
2017 | |
2018 | for (i = 0; i < num; i++) { |
2019 | |
2020 | aa_buf = kmalloc(size: aa_g_path_max, GFP_KERNEL | |
2021 | __GFP_RETRY_MAYFAIL | __GFP_NOWARN); |
2022 | if (!aa_buf) { |
2023 | destroy_buffers(); |
2024 | return -ENOMEM; |
2025 | } |
2026 | aa_put_buffer(buf: aa_buf->buffer); |
2027 | } |
2028 | return 0; |
2029 | } |
2030 | |
2031 | #ifdef CONFIG_SYSCTL |
2032 | static int apparmor_dointvec(struct ctl_table *table, int write, |
2033 | void *buffer, size_t *lenp, loff_t *ppos) |
2034 | { |
2035 | if (!aa_current_policy_admin_capable(NULL)) |
2036 | return -EPERM; |
2037 | if (!apparmor_enabled) |
2038 | return -EINVAL; |
2039 | |
2040 | return proc_dointvec(table, write, buffer, lenp, ppos); |
2041 | } |
2042 | |
2043 | static struct ctl_table apparmor_sysctl_table[] = { |
2044 | #ifdef CONFIG_USER_NS |
2045 | { |
2046 | .procname = "unprivileged_userns_apparmor_policy" , |
2047 | .data = &unprivileged_userns_apparmor_policy, |
2048 | .maxlen = sizeof(int), |
2049 | .mode = 0600, |
2050 | .proc_handler = apparmor_dointvec, |
2051 | }, |
2052 | #endif /* CONFIG_USER_NS */ |
2053 | { |
2054 | .procname = "apparmor_display_secid_mode" , |
2055 | .data = &apparmor_display_secid_mode, |
2056 | .maxlen = sizeof(int), |
2057 | .mode = 0600, |
2058 | .proc_handler = apparmor_dointvec, |
2059 | }, |
2060 | { |
2061 | .procname = "apparmor_restrict_unprivileged_unconfined" , |
2062 | .data = &aa_unprivileged_unconfined_restricted, |
2063 | .maxlen = sizeof(int), |
2064 | .mode = 0600, |
2065 | .proc_handler = apparmor_dointvec, |
2066 | }, |
2067 | { } |
2068 | }; |
2069 | |
2070 | static int __init apparmor_init_sysctl(void) |
2071 | { |
2072 | return register_sysctl("kernel" , apparmor_sysctl_table) ? 0 : -ENOMEM; |
2073 | } |
2074 | #else |
2075 | static inline int apparmor_init_sysctl(void) |
2076 | { |
2077 | return 0; |
2078 | } |
2079 | #endif /* CONFIG_SYSCTL */ |
2080 | |
2081 | #if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK) |
2082 | static unsigned int apparmor_ip_postroute(void *priv, |
2083 | struct sk_buff *skb, |
2084 | const struct nf_hook_state *state) |
2085 | { |
2086 | struct aa_sk_ctx *ctx; |
2087 | struct sock *sk; |
2088 | |
2089 | if (!skb->secmark) |
2090 | return NF_ACCEPT; |
2091 | |
2092 | sk = skb_to_full_sk(skb); |
2093 | if (sk == NULL) |
2094 | return NF_ACCEPT; |
2095 | |
2096 | ctx = aa_sock(sk); |
2097 | if (!apparmor_secmark_check(label: ctx->label, OP_SENDMSG, AA_MAY_SEND, |
2098 | secid: skb->secmark, sk)) |
2099 | return NF_ACCEPT; |
2100 | |
2101 | return NF_DROP_ERR(-ECONNREFUSED); |
2102 | |
2103 | } |
2104 | |
2105 | static const struct nf_hook_ops apparmor_nf_ops[] = { |
2106 | { |
2107 | .hook = apparmor_ip_postroute, |
2108 | .pf = NFPROTO_IPV4, |
2109 | .hooknum = NF_INET_POST_ROUTING, |
2110 | .priority = NF_IP_PRI_SELINUX_FIRST, |
2111 | }, |
2112 | #if IS_ENABLED(CONFIG_IPV6) |
2113 | { |
2114 | .hook = apparmor_ip_postroute, |
2115 | .pf = NFPROTO_IPV6, |
2116 | .hooknum = NF_INET_POST_ROUTING, |
2117 | .priority = NF_IP6_PRI_SELINUX_FIRST, |
2118 | }, |
2119 | #endif |
2120 | }; |
2121 | |
2122 | static int __net_init apparmor_nf_register(struct net *net) |
2123 | { |
2124 | return nf_register_net_hooks(net, reg: apparmor_nf_ops, |
2125 | ARRAY_SIZE(apparmor_nf_ops)); |
2126 | } |
2127 | |
2128 | static void __net_exit apparmor_nf_unregister(struct net *net) |
2129 | { |
2130 | nf_unregister_net_hooks(net, reg: apparmor_nf_ops, |
2131 | ARRAY_SIZE(apparmor_nf_ops)); |
2132 | } |
2133 | |
2134 | static struct pernet_operations apparmor_net_ops = { |
2135 | .init = apparmor_nf_register, |
2136 | .exit = apparmor_nf_unregister, |
2137 | }; |
2138 | |
2139 | static int __init apparmor_nf_ip_init(void) |
2140 | { |
2141 | int err; |
2142 | |
2143 | if (!apparmor_enabled) |
2144 | return 0; |
2145 | |
2146 | err = register_pernet_subsys(&apparmor_net_ops); |
2147 | if (err) |
2148 | panic(fmt: "Apparmor: register_pernet_subsys: error %d\n" , err); |
2149 | |
2150 | return 0; |
2151 | } |
2152 | __initcall(apparmor_nf_ip_init); |
2153 | #endif |
2154 | |
2155 | static char nulldfa_src[] = { |
2156 | #include "nulldfa.in" |
2157 | }; |
2158 | static struct aa_dfa *nulldfa; |
2159 | |
2160 | static char stacksplitdfa_src[] = { |
2161 | #include "stacksplitdfa.in" |
2162 | }; |
2163 | struct aa_dfa *stacksplitdfa; |
2164 | struct aa_policydb *nullpdb; |
2165 | |
2166 | static int __init aa_setup_dfa_engine(void) |
2167 | { |
2168 | int error = -ENOMEM; |
2169 | |
2170 | nullpdb = aa_alloc_pdb(GFP_KERNEL); |
2171 | if (!nullpdb) |
2172 | return -ENOMEM; |
2173 | |
2174 | nulldfa = aa_dfa_unpack(blob: nulldfa_src, size: sizeof(nulldfa_src), |
2175 | TO_ACCEPT1_FLAG(YYTD_DATA32) | |
2176 | TO_ACCEPT2_FLAG(YYTD_DATA32)); |
2177 | if (IS_ERR(ptr: nulldfa)) { |
2178 | error = PTR_ERR(ptr: nulldfa); |
2179 | goto fail; |
2180 | } |
2181 | nullpdb->dfa = aa_get_dfa(dfa: nulldfa); |
2182 | nullpdb->perms = kcalloc(n: 2, size: sizeof(struct aa_perms), GFP_KERNEL); |
2183 | if (!nullpdb->perms) |
2184 | goto fail; |
2185 | nullpdb->size = 2; |
2186 | |
2187 | stacksplitdfa = aa_dfa_unpack(blob: stacksplitdfa_src, |
2188 | size: sizeof(stacksplitdfa_src), |
2189 | TO_ACCEPT1_FLAG(YYTD_DATA32) | |
2190 | TO_ACCEPT2_FLAG(YYTD_DATA32)); |
2191 | if (IS_ERR(ptr: stacksplitdfa)) { |
2192 | error = PTR_ERR(ptr: stacksplitdfa); |
2193 | goto fail; |
2194 | } |
2195 | |
2196 | return 0; |
2197 | |
2198 | fail: |
2199 | aa_put_pdb(pdb: nullpdb); |
2200 | aa_put_dfa(dfa: nulldfa); |
2201 | nullpdb = NULL; |
2202 | nulldfa = NULL; |
2203 | stacksplitdfa = NULL; |
2204 | |
2205 | return error; |
2206 | } |
2207 | |
2208 | static void __init aa_teardown_dfa_engine(void) |
2209 | { |
2210 | aa_put_dfa(dfa: stacksplitdfa); |
2211 | aa_put_dfa(dfa: nulldfa); |
2212 | aa_put_pdb(pdb: nullpdb); |
2213 | nullpdb = NULL; |
2214 | stacksplitdfa = NULL; |
2215 | nulldfa = NULL; |
2216 | } |
2217 | |
2218 | static int __init apparmor_init(void) |
2219 | { |
2220 | int error; |
2221 | |
2222 | error = aa_setup_dfa_engine(); |
2223 | if (error) { |
2224 | AA_ERROR("Unable to setup dfa engine\n" ); |
2225 | goto alloc_out; |
2226 | } |
2227 | |
2228 | error = aa_alloc_root_ns(); |
2229 | if (error) { |
2230 | AA_ERROR("Unable to allocate default profile namespace\n" ); |
2231 | goto alloc_out; |
2232 | } |
2233 | |
2234 | error = apparmor_init_sysctl(); |
2235 | if (error) { |
2236 | AA_ERROR("Unable to register sysctls\n" ); |
2237 | goto alloc_out; |
2238 | |
2239 | } |
2240 | |
2241 | error = alloc_buffers(); |
2242 | if (error) { |
2243 | AA_ERROR("Unable to allocate work buffers\n" ); |
2244 | goto alloc_out; |
2245 | } |
2246 | |
2247 | error = set_init_ctx(); |
2248 | if (error) { |
2249 | AA_ERROR("Failed to set context on init task\n" ); |
2250 | aa_free_root_ns(); |
2251 | goto buffers_out; |
2252 | } |
2253 | security_add_hooks(hooks: apparmor_hooks, ARRAY_SIZE(apparmor_hooks), |
2254 | lsmid: &apparmor_lsmid); |
2255 | |
2256 | /* Report that AppArmor successfully initialized */ |
2257 | apparmor_initialized = 1; |
2258 | if (aa_g_profile_mode == APPARMOR_COMPLAIN) |
2259 | aa_info_message(str: "AppArmor initialized: complain mode enabled" ); |
2260 | else if (aa_g_profile_mode == APPARMOR_KILL) |
2261 | aa_info_message(str: "AppArmor initialized: kill mode enabled" ); |
2262 | else |
2263 | aa_info_message(str: "AppArmor initialized" ); |
2264 | |
2265 | return error; |
2266 | |
2267 | buffers_out: |
2268 | destroy_buffers(); |
2269 | alloc_out: |
2270 | aa_destroy_aafs(); |
2271 | aa_teardown_dfa_engine(); |
2272 | |
2273 | apparmor_enabled = false; |
2274 | return error; |
2275 | } |
2276 | |
2277 | DEFINE_LSM(apparmor) = { |
2278 | .name = "apparmor" , |
2279 | .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, |
2280 | .enabled = &apparmor_enabled, |
2281 | .blobs = &apparmor_blob_sizes, |
2282 | .init = apparmor_init, |
2283 | }; |
2284 | |