1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef __NET_NETLINK_H |
3 | #define __NET_NETLINK_H |
4 | |
5 | #include <linux/types.h> |
6 | #include <linux/netlink.h> |
7 | #include <linux/jiffies.h> |
8 | #include <linux/in6.h> |
9 | |
10 | /* ======================================================================== |
11 | * Netlink Messages and Attributes Interface (As Seen On TV) |
12 | * ------------------------------------------------------------------------ |
13 | * Messages Interface |
14 | * ------------------------------------------------------------------------ |
15 | * |
16 | * Message Format: |
17 | * <--- nlmsg_total_size(payload) ---> |
18 | * <-- nlmsg_msg_size(payload) -> |
19 | * +----------+- - -+-------------+- - -+-------- - - |
20 | * | nlmsghdr | Pad | Payload | Pad | nlmsghdr |
21 | * +----------+- - -+-------------+- - -+-------- - - |
22 | * nlmsg_data(nlh)---^ ^ |
23 | * nlmsg_next(nlh)-----------------------+ |
24 | * |
25 | * Payload Format: |
26 | * <---------------------- nlmsg_len(nlh) ---------------------> |
27 | * <------ hdrlen ------> <- nlmsg_attrlen(nlh, hdrlen) -> |
28 | * +----------------------+- - -+--------------------------------+ |
29 | * | Family Header | Pad | Attributes | |
30 | * +----------------------+- - -+--------------------------------+ |
31 | * nlmsg_attrdata(nlh, hdrlen)---^ |
32 | * |
33 | * Data Structures: |
34 | * struct nlmsghdr netlink message header |
35 | * |
36 | * Message Construction: |
37 | * nlmsg_new() create a new netlink message |
38 | * nlmsg_put() add a netlink message to an skb |
39 | * nlmsg_put_answer() callback based nlmsg_put() |
40 | * nlmsg_end() finalize netlink message |
41 | * nlmsg_get_pos() return current position in message |
42 | * nlmsg_trim() trim part of message |
43 | * nlmsg_cancel() cancel message construction |
44 | * nlmsg_free() free a netlink message |
45 | * |
46 | * Message Sending: |
47 | * nlmsg_multicast() multicast message to several groups |
48 | * nlmsg_unicast() unicast a message to a single socket |
49 | * nlmsg_notify() send notification message |
50 | * |
51 | * Message Length Calculations: |
52 | * nlmsg_msg_size(payload) length of message w/o padding |
53 | * nlmsg_total_size(payload) length of message w/ padding |
54 | * nlmsg_padlen(payload) length of padding at tail |
55 | * |
56 | * Message Payload Access: |
57 | * nlmsg_data(nlh) head of message payload |
58 | * nlmsg_len(nlh) length of message payload |
59 | * nlmsg_attrdata(nlh, hdrlen) head of attributes data |
60 | * nlmsg_attrlen(nlh, hdrlen) length of attributes data |
61 | * |
62 | * Message Parsing: |
63 | * nlmsg_ok(nlh, remaining) does nlh fit into remaining bytes? |
64 | * nlmsg_next(nlh, remaining) get next netlink message |
65 | * nlmsg_parse() parse attributes of a message |
66 | * nlmsg_find_attr() find an attribute in a message |
67 | * nlmsg_for_each_msg() loop over all messages |
68 | * nlmsg_validate() validate netlink message incl. attrs |
69 | * nlmsg_for_each_attr() loop over all attributes |
70 | * |
71 | * Misc: |
72 | * nlmsg_report() report back to application? |
73 | * |
74 | * ------------------------------------------------------------------------ |
75 | * Attributes Interface |
76 | * ------------------------------------------------------------------------ |
77 | * |
78 | * Attribute Format: |
79 | * <------- nla_total_size(payload) -------> |
80 | * <---- nla_attr_size(payload) -----> |
81 | * +----------+- - -+- - - - - - - - - +- - -+-------- - - |
82 | * | Header | Pad | Payload | Pad | Header |
83 | * +----------+- - -+- - - - - - - - - +- - -+-------- - - |
84 | * <- nla_len(nla) -> ^ |
85 | * nla_data(nla)----^ | |
86 | * nla_next(nla)-----------------------------' |
87 | * |
88 | * Data Structures: |
89 | * struct nlattr netlink attribute header |
90 | * |
91 | * Attribute Construction: |
92 | * nla_reserve(skb, type, len) reserve room for an attribute |
93 | * nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr |
94 | * nla_put(skb, type, len, data) add attribute to skb |
95 | * nla_put_nohdr(skb, len, data) add attribute w/o hdr |
96 | * nla_append(skb, len, data) append data to skb |
97 | * |
98 | * Attribute Construction for Basic Types: |
99 | * nla_put_u8(skb, type, value) add u8 attribute to skb |
100 | * nla_put_u16(skb, type, value) add u16 attribute to skb |
101 | * nla_put_u32(skb, type, value) add u32 attribute to skb |
102 | * nla_put_u64_64bit(skb, type, |
103 | * value, padattr) add u64 attribute to skb |
104 | * nla_put_s8(skb, type, value) add s8 attribute to skb |
105 | * nla_put_s16(skb, type, value) add s16 attribute to skb |
106 | * nla_put_s32(skb, type, value) add s32 attribute to skb |
107 | * nla_put_s64(skb, type, value, |
108 | * padattr) add s64 attribute to skb |
109 | * nla_put_string(skb, type, str) add string attribute to skb |
110 | * nla_put_flag(skb, type) add flag attribute to skb |
111 | * nla_put_msecs(skb, type, jiffies, |
112 | * padattr) add msecs attribute to skb |
113 | * nla_put_in_addr(skb, type, addr) add IPv4 address attribute to skb |
114 | * nla_put_in6_addr(skb, type, addr) add IPv6 address attribute to skb |
115 | * |
116 | * Nested Attributes Construction: |
117 | * nla_nest_start(skb, type) start a nested attribute |
118 | * nla_nest_end(skb, nla) finalize a nested attribute |
119 | * nla_nest_cancel(skb, nla) cancel nested attribute construction |
120 | * |
121 | * Attribute Length Calculations: |
122 | * nla_attr_size(payload) length of attribute w/o padding |
123 | * nla_total_size(payload) length of attribute w/ padding |
124 | * nla_padlen(payload) length of padding |
125 | * |
126 | * Attribute Payload Access: |
127 | * nla_data(nla) head of attribute payload |
128 | * nla_len(nla) length of attribute payload |
129 | * |
130 | * Attribute Payload Access for Basic Types: |
131 | * nla_get_uint(nla) get payload for a uint attribute |
132 | * nla_get_sint(nla) get payload for a sint attribute |
133 | * nla_get_u8(nla) get payload for a u8 attribute |
134 | * nla_get_u16(nla) get payload for a u16 attribute |
135 | * nla_get_u32(nla) get payload for a u32 attribute |
136 | * nla_get_u64(nla) get payload for a u64 attribute |
137 | * nla_get_s8(nla) get payload for a s8 attribute |
138 | * nla_get_s16(nla) get payload for a s16 attribute |
139 | * nla_get_s32(nla) get payload for a s32 attribute |
140 | * nla_get_s64(nla) get payload for a s64 attribute |
141 | * nla_get_flag(nla) return 1 if flag is true |
142 | * nla_get_msecs(nla) get payload for a msecs attribute |
143 | * |
144 | * Attribute Misc: |
145 | * nla_memcpy(dest, nla, count) copy attribute into memory |
146 | * nla_memcmp(nla, data, size) compare attribute with memory area |
147 | * nla_strscpy(dst, nla, size) copy attribute to a sized string |
148 | * nla_strcmp(nla, str) compare attribute with string |
149 | * |
150 | * Attribute Parsing: |
151 | * nla_ok(nla, remaining) does nla fit into remaining bytes? |
152 | * nla_next(nla, remaining) get next netlink attribute |
153 | * nla_validate() validate a stream of attributes |
154 | * nla_validate_nested() validate a stream of nested attributes |
155 | * nla_find() find attribute in stream of attributes |
156 | * nla_find_nested() find attribute in nested attributes |
157 | * nla_parse() parse and validate stream of attrs |
158 | * nla_parse_nested() parse nested attributes |
159 | * nla_for_each_attr() loop over all attributes |
160 | * nla_for_each_nested() loop over the nested attributes |
161 | *========================================================================= |
162 | */ |
163 | |
164 | /** |
165 | * Standard attribute types to specify validation policy |
166 | */ |
167 | enum { |
168 | NLA_UNSPEC, |
169 | NLA_U8, |
170 | NLA_U16, |
171 | NLA_U32, |
172 | NLA_U64, |
173 | NLA_STRING, |
174 | NLA_FLAG, |
175 | NLA_MSECS, |
176 | NLA_NESTED, |
177 | NLA_NESTED_ARRAY, |
178 | NLA_NUL_STRING, |
179 | NLA_BINARY, |
180 | NLA_S8, |
181 | NLA_S16, |
182 | NLA_S32, |
183 | NLA_S64, |
184 | NLA_BITFIELD32, |
185 | NLA_REJECT, |
186 | NLA_BE16, |
187 | NLA_BE32, |
188 | NLA_SINT, |
189 | NLA_UINT, |
190 | __NLA_TYPE_MAX, |
191 | }; |
192 | |
193 | #define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1) |
194 | |
195 | struct netlink_range_validation { |
196 | u64 min, max; |
197 | }; |
198 | |
199 | struct netlink_range_validation_signed { |
200 | s64 min, max; |
201 | }; |
202 | |
203 | enum nla_policy_validation { |
204 | NLA_VALIDATE_NONE, |
205 | NLA_VALIDATE_RANGE, |
206 | NLA_VALIDATE_RANGE_WARN_TOO_LONG, |
207 | NLA_VALIDATE_MIN, |
208 | NLA_VALIDATE_MAX, |
209 | NLA_VALIDATE_MASK, |
210 | NLA_VALIDATE_RANGE_PTR, |
211 | NLA_VALIDATE_FUNCTION, |
212 | }; |
213 | |
214 | /** |
215 | * struct nla_policy - attribute validation policy |
216 | * @type: Type of attribute or NLA_UNSPEC |
217 | * @validation_type: type of attribute validation done in addition to |
218 | * type-specific validation (e.g. range, function call), see |
219 | * &enum nla_policy_validation |
220 | * @len: Type specific length of payload |
221 | * |
222 | * Policies are defined as arrays of this struct, the array must be |
223 | * accessible by attribute type up to the highest identifier to be expected. |
224 | * |
225 | * Meaning of `len' field: |
226 | * NLA_STRING Maximum length of string |
227 | * NLA_NUL_STRING Maximum length of string (excluding NUL) |
228 | * NLA_FLAG Unused |
229 | * NLA_BINARY Maximum length of attribute payload |
230 | * (but see also below with the validation type) |
231 | * NLA_NESTED, |
232 | * NLA_NESTED_ARRAY Length verification is done by checking len of |
233 | * nested header (or empty); len field is used if |
234 | * nested_policy is also used, for the max attr |
235 | * number in the nested policy. |
236 | * NLA_SINT, NLA_UINT, |
237 | * NLA_U8, NLA_U16, |
238 | * NLA_U32, NLA_U64, |
239 | * NLA_S8, NLA_S16, |
240 | * NLA_S32, NLA_S64, |
241 | * NLA_BE16, NLA_BE32, |
242 | * NLA_MSECS Leaving the length field zero will verify the |
243 | * given type fits, using it verifies minimum length |
244 | * just like "All other" |
245 | * NLA_BITFIELD32 Unused |
246 | * NLA_REJECT Unused |
247 | * All other Minimum length of attribute payload |
248 | * |
249 | * Meaning of validation union: |
250 | * NLA_BITFIELD32 This is a 32-bit bitmap/bitselector attribute and |
251 | * `bitfield32_valid' is the u32 value of valid flags |
252 | * NLA_REJECT This attribute is always rejected and `reject_message' |
253 | * may point to a string to report as the error instead |
254 | * of the generic one in extended ACK. |
255 | * NLA_NESTED `nested_policy' to a nested policy to validate, must |
256 | * also set `len' to the max attribute number. Use the |
257 | * provided NLA_POLICY_NESTED() macro. |
258 | * Note that nla_parse() will validate, but of course not |
259 | * parse, the nested sub-policies. |
260 | * NLA_NESTED_ARRAY `nested_policy' points to a nested policy to validate, |
261 | * must also set `len' to the max attribute number. Use |
262 | * the provided NLA_POLICY_NESTED_ARRAY() macro. |
263 | * The difference to NLA_NESTED is the structure: |
264 | * NLA_NESTED has the nested attributes directly inside |
265 | * while an array has the nested attributes at another |
266 | * level down and the attribute types directly in the |
267 | * nesting don't matter. |
268 | * NLA_UINT, |
269 | * NLA_U8, |
270 | * NLA_U16, |
271 | * NLA_U32, |
272 | * NLA_U64, |
273 | * NLA_BE16, |
274 | * NLA_BE32, |
275 | * NLA_SINT, |
276 | * NLA_S8, |
277 | * NLA_S16, |
278 | * NLA_S32, |
279 | * NLA_S64 The `min' and `max' fields are used depending on the |
280 | * validation_type field, if that is min/max/range then |
281 | * the min, max or both are used (respectively) to check |
282 | * the value of the integer attribute. |
283 | * Note that in the interest of code simplicity and |
284 | * struct size both limits are s16, so you cannot |
285 | * enforce a range that doesn't fall within the range |
286 | * of s16 - do that using the NLA_POLICY_FULL_RANGE() |
287 | * or NLA_POLICY_FULL_RANGE_SIGNED() macros instead. |
288 | * Use the NLA_POLICY_MIN(), NLA_POLICY_MAX() and |
289 | * NLA_POLICY_RANGE() macros. |
290 | * NLA_UINT, |
291 | * NLA_U8, |
292 | * NLA_U16, |
293 | * NLA_U32, |
294 | * NLA_U64 If the validation_type field instead is set to |
295 | * NLA_VALIDATE_RANGE_PTR, `range' must be a pointer |
296 | * to a struct netlink_range_validation that indicates |
297 | * the min/max values. |
298 | * Use NLA_POLICY_FULL_RANGE(). |
299 | * NLA_SINT, |
300 | * NLA_S8, |
301 | * NLA_S16, |
302 | * NLA_S32, |
303 | * NLA_S64 If the validation_type field instead is set to |
304 | * NLA_VALIDATE_RANGE_PTR, `range_signed' must be a |
305 | * pointer to a struct netlink_range_validation_signed |
306 | * that indicates the min/max values. |
307 | * Use NLA_POLICY_FULL_RANGE_SIGNED(). |
308 | * |
309 | * NLA_BINARY If the validation type is like the ones for integers |
310 | * above, then the min/max length (not value like for |
311 | * integers) of the attribute is enforced. |
312 | * |
313 | * All other Unused - but note that it's a union |
314 | * |
315 | * Meaning of `validate' field, use via NLA_POLICY_VALIDATE_FN: |
316 | * NLA_BINARY Validation function called for the attribute. |
317 | * All other Unused - but note that it's a union |
318 | * |
319 | * Example: |
320 | * |
321 | * static const u32 myvalidflags = 0xff231023; |
322 | * |
323 | * static const struct nla_policy my_policy[ATTR_MAX+1] = { |
324 | * [ATTR_FOO] = { .type = NLA_U16 }, |
325 | * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ }, |
326 | * [ATTR_BAZ] = NLA_POLICY_EXACT_LEN(sizeof(struct mystruct)), |
327 | * [ATTR_GOO] = NLA_POLICY_BITFIELD32(myvalidflags), |
328 | * }; |
329 | */ |
330 | struct nla_policy { |
331 | u8 type; |
332 | u8 validation_type; |
333 | u16 len; |
334 | union { |
335 | /** |
336 | * @strict_start_type: first attribute to validate strictly |
337 | * |
338 | * This entry is special, and used for the attribute at index 0 |
339 | * only, and specifies special data about the policy, namely it |
340 | * specifies the "boundary type" where strict length validation |
341 | * starts for any attribute types >= this value, also, strict |
342 | * nesting validation starts here. |
343 | * |
344 | * Additionally, it means that NLA_UNSPEC is actually NLA_REJECT |
345 | * for any types >= this, so need to use NLA_POLICY_MIN_LEN() to |
346 | * get the previous pure { .len = xyz } behaviour. The advantage |
347 | * of this is that types not specified in the policy will be |
348 | * rejected. |
349 | * |
350 | * For completely new families it should be set to 1 so that the |
351 | * validation is enforced for all attributes. For existing ones |
352 | * it should be set at least when new attributes are added to |
353 | * the enum used by the policy, and be set to the new value that |
354 | * was added to enforce strict validation from thereon. |
355 | */ |
356 | u16 strict_start_type; |
357 | |
358 | /* private: use NLA_POLICY_*() to set */ |
359 | const u32 bitfield32_valid; |
360 | const u32 mask; |
361 | const char *reject_message; |
362 | const struct nla_policy *nested_policy; |
363 | const struct netlink_range_validation *range; |
364 | const struct netlink_range_validation_signed *range_signed; |
365 | struct { |
366 | s16 min, max; |
367 | }; |
368 | int (*validate)(const struct nlattr *attr, |
369 | struct netlink_ext_ack *extack); |
370 | }; |
371 | }; |
372 | |
373 | #define NLA_POLICY_ETH_ADDR NLA_POLICY_EXACT_LEN(ETH_ALEN) |
374 | #define NLA_POLICY_ETH_ADDR_COMPAT NLA_POLICY_EXACT_LEN_WARN(ETH_ALEN) |
375 | |
376 | #define _NLA_POLICY_NESTED(maxattr, policy) \ |
377 | { .type = NLA_NESTED, .nested_policy = policy, .len = maxattr } |
378 | #define _NLA_POLICY_NESTED_ARRAY(maxattr, policy) \ |
379 | { .type = NLA_NESTED_ARRAY, .nested_policy = policy, .len = maxattr } |
380 | #define NLA_POLICY_NESTED(policy) \ |
381 | _NLA_POLICY_NESTED(ARRAY_SIZE(policy) - 1, policy) |
382 | #define NLA_POLICY_NESTED_ARRAY(policy) \ |
383 | _NLA_POLICY_NESTED_ARRAY(ARRAY_SIZE(policy) - 1, policy) |
384 | #define NLA_POLICY_BITFIELD32(valid) \ |
385 | { .type = NLA_BITFIELD32, .bitfield32_valid = valid } |
386 | |
387 | #define __NLA_IS_UINT_TYPE(tp) \ |
388 | (tp == NLA_U8 || tp == NLA_U16 || tp == NLA_U32 || \ |
389 | tp == NLA_U64 || tp == NLA_UINT || \ |
390 | tp == NLA_BE16 || tp == NLA_BE32) |
391 | #define __NLA_IS_SINT_TYPE(tp) \ |
392 | (tp == NLA_S8 || tp == NLA_S16 || tp == NLA_S32 || tp == NLA_S64 || \ |
393 | tp == NLA_SINT) |
394 | |
395 | #define __NLA_ENSURE(condition) BUILD_BUG_ON_ZERO(!(condition)) |
396 | #define NLA_ENSURE_UINT_TYPE(tp) \ |
397 | (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp)) + tp) |
398 | #define NLA_ENSURE_UINT_OR_BINARY_TYPE(tp) \ |
399 | (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp) || \ |
400 | tp == NLA_MSECS || \ |
401 | tp == NLA_BINARY) + tp) |
402 | #define NLA_ENSURE_SINT_TYPE(tp) \ |
403 | (__NLA_ENSURE(__NLA_IS_SINT_TYPE(tp)) + tp) |
404 | #define NLA_ENSURE_INT_OR_BINARY_TYPE(tp) \ |
405 | (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp) || \ |
406 | __NLA_IS_SINT_TYPE(tp) || \ |
407 | tp == NLA_MSECS || \ |
408 | tp == NLA_BINARY) + tp) |
409 | #define NLA_ENSURE_NO_VALIDATION_PTR(tp) \ |
410 | (__NLA_ENSURE(tp != NLA_BITFIELD32 && \ |
411 | tp != NLA_REJECT && \ |
412 | tp != NLA_NESTED && \ |
413 | tp != NLA_NESTED_ARRAY) + tp) |
414 | |
415 | #define NLA_POLICY_RANGE(tp, _min, _max) { \ |
416 | .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \ |
417 | .validation_type = NLA_VALIDATE_RANGE, \ |
418 | .min = _min, \ |
419 | .max = _max \ |
420 | } |
421 | |
422 | #define NLA_POLICY_FULL_RANGE(tp, _range) { \ |
423 | .type = NLA_ENSURE_UINT_OR_BINARY_TYPE(tp), \ |
424 | .validation_type = NLA_VALIDATE_RANGE_PTR, \ |
425 | .range = _range, \ |
426 | } |
427 | |
428 | #define NLA_POLICY_FULL_RANGE_SIGNED(tp, _range) { \ |
429 | .type = NLA_ENSURE_SINT_TYPE(tp), \ |
430 | .validation_type = NLA_VALIDATE_RANGE_PTR, \ |
431 | .range_signed = _range, \ |
432 | } |
433 | |
434 | #define NLA_POLICY_MIN(tp, _min) { \ |
435 | .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \ |
436 | .validation_type = NLA_VALIDATE_MIN, \ |
437 | .min = _min, \ |
438 | } |
439 | |
440 | #define NLA_POLICY_MAX(tp, _max) { \ |
441 | .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \ |
442 | .validation_type = NLA_VALIDATE_MAX, \ |
443 | .max = _max, \ |
444 | } |
445 | |
446 | #define NLA_POLICY_MASK(tp, _mask) { \ |
447 | .type = NLA_ENSURE_UINT_TYPE(tp), \ |
448 | .validation_type = NLA_VALIDATE_MASK, \ |
449 | .mask = _mask, \ |
450 | } |
451 | |
452 | #define NLA_POLICY_VALIDATE_FN(tp, fn, ...) { \ |
453 | .type = NLA_ENSURE_NO_VALIDATION_PTR(tp), \ |
454 | .validation_type = NLA_VALIDATE_FUNCTION, \ |
455 | .validate = fn, \ |
456 | .len = __VA_ARGS__ + 0, \ |
457 | } |
458 | |
459 | #define NLA_POLICY_EXACT_LEN(_len) NLA_POLICY_RANGE(NLA_BINARY, _len, _len) |
460 | #define NLA_POLICY_EXACT_LEN_WARN(_len) { \ |
461 | .type = NLA_BINARY, \ |
462 | .validation_type = NLA_VALIDATE_RANGE_WARN_TOO_LONG, \ |
463 | .min = _len, \ |
464 | .max = _len \ |
465 | } |
466 | #define NLA_POLICY_MIN_LEN(_len) NLA_POLICY_MIN(NLA_BINARY, _len) |
467 | |
468 | /** |
469 | * struct nl_info - netlink source information |
470 | * @nlh: Netlink message header of original request |
471 | * @nl_net: Network namespace |
472 | * @portid: Netlink PORTID of requesting application |
473 | * @skip_notify: Skip netlink notifications to user space |
474 | * @skip_notify_kernel: Skip selected in-kernel notifications |
475 | */ |
476 | struct nl_info { |
477 | struct nlmsghdr *nlh; |
478 | struct net *nl_net; |
479 | u32 portid; |
480 | u8 skip_notify:1, |
481 | skip_notify_kernel:1; |
482 | }; |
483 | |
484 | /** |
485 | * enum netlink_validation - netlink message/attribute validation levels |
486 | * @NL_VALIDATE_LIBERAL: Old-style "be liberal" validation, not caring about |
487 | * extra data at the end of the message, attributes being longer than |
488 | * they should be, or unknown attributes being present. |
489 | * @NL_VALIDATE_TRAILING: Reject junk data encountered after attribute parsing. |
490 | * @NL_VALIDATE_MAXTYPE: Reject attributes > max type; Together with _TRAILING |
491 | * this is equivalent to the old nla_parse_strict()/nlmsg_parse_strict(). |
492 | * @NL_VALIDATE_UNSPEC: Reject attributes with NLA_UNSPEC in the policy. |
493 | * This can safely be set by the kernel when the given policy has no |
494 | * NLA_UNSPEC anymore, and can thus be used to ensure policy entries |
495 | * are enforced going forward. |
496 | * @NL_VALIDATE_STRICT_ATTRS: strict attribute policy parsing (e.g. |
497 | * U8, U16, U32 must have exact size, etc.) |
498 | * @NL_VALIDATE_NESTED: Check that NLA_F_NESTED is set for NLA_NESTED(_ARRAY) |
499 | * and unset for other policies. |
500 | */ |
501 | enum netlink_validation { |
502 | NL_VALIDATE_LIBERAL = 0, |
503 | NL_VALIDATE_TRAILING = BIT(0), |
504 | NL_VALIDATE_MAXTYPE = BIT(1), |
505 | NL_VALIDATE_UNSPEC = BIT(2), |
506 | NL_VALIDATE_STRICT_ATTRS = BIT(3), |
507 | NL_VALIDATE_NESTED = BIT(4), |
508 | }; |
509 | |
510 | #define NL_VALIDATE_DEPRECATED_STRICT (NL_VALIDATE_TRAILING |\ |
511 | NL_VALIDATE_MAXTYPE) |
512 | #define NL_VALIDATE_STRICT (NL_VALIDATE_TRAILING |\ |
513 | NL_VALIDATE_MAXTYPE |\ |
514 | NL_VALIDATE_UNSPEC |\ |
515 | NL_VALIDATE_STRICT_ATTRS |\ |
516 | NL_VALIDATE_NESTED) |
517 | |
518 | int netlink_rcv_skb(struct sk_buff *skb, |
519 | int (*cb)(struct sk_buff *, struct nlmsghdr *, |
520 | struct netlink_ext_ack *)); |
521 | int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid, |
522 | unsigned int group, int report, gfp_t flags); |
523 | |
524 | int __nla_validate(const struct nlattr *head, int len, int maxtype, |
525 | const struct nla_policy *policy, unsigned int validate, |
526 | struct netlink_ext_ack *extack); |
527 | int __nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, |
528 | int len, const struct nla_policy *policy, unsigned int validate, |
529 | struct netlink_ext_ack *extack); |
530 | int nla_policy_len(const struct nla_policy *, int); |
531 | struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype); |
532 | ssize_t nla_strscpy(char *dst, const struct nlattr *nla, size_t dstsize); |
533 | char *nla_strdup(const struct nlattr *nla, gfp_t flags); |
534 | int nla_memcpy(void *dest, const struct nlattr *src, int count); |
535 | int nla_memcmp(const struct nlattr *nla, const void *data, size_t size); |
536 | int nla_strcmp(const struct nlattr *nla, const char *str); |
537 | struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen); |
538 | struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype, |
539 | int attrlen, int padattr); |
540 | void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen); |
541 | struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen); |
542 | struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype, |
543 | int attrlen, int padattr); |
544 | void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen); |
545 | void __nla_put(struct sk_buff *skb, int attrtype, int attrlen, |
546 | const void *data); |
547 | void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen, |
548 | const void *data, int padattr); |
549 | void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data); |
550 | int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data); |
551 | int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen, |
552 | const void *data, int padattr); |
553 | int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data); |
554 | int nla_append(struct sk_buff *skb, int attrlen, const void *data); |
555 | |
556 | /************************************************************************** |
557 | * Netlink Messages |
558 | **************************************************************************/ |
559 | |
560 | /** |
561 | * nlmsg_msg_size - length of netlink message not including padding |
562 | * @payload: length of message payload |
563 | */ |
564 | static inline int nlmsg_msg_size(int payload) |
565 | { |
566 | return NLMSG_HDRLEN + payload; |
567 | } |
568 | |
569 | /** |
570 | * nlmsg_total_size - length of netlink message including padding |
571 | * @payload: length of message payload |
572 | */ |
573 | static inline int nlmsg_total_size(int payload) |
574 | { |
575 | return NLMSG_ALIGN(nlmsg_msg_size(payload)); |
576 | } |
577 | |
578 | /** |
579 | * nlmsg_padlen - length of padding at the message's tail |
580 | * @payload: length of message payload |
581 | */ |
582 | static inline int nlmsg_padlen(int payload) |
583 | { |
584 | return nlmsg_total_size(payload) - nlmsg_msg_size(payload); |
585 | } |
586 | |
587 | /** |
588 | * nlmsg_data - head of message payload |
589 | * @nlh: netlink message header |
590 | */ |
591 | static inline void *nlmsg_data(const struct nlmsghdr *nlh) |
592 | { |
593 | return (unsigned char *) nlh + NLMSG_HDRLEN; |
594 | } |
595 | |
596 | /** |
597 | * nlmsg_len - length of message payload |
598 | * @nlh: netlink message header |
599 | */ |
600 | static inline int nlmsg_len(const struct nlmsghdr *nlh) |
601 | { |
602 | return nlh->nlmsg_len - NLMSG_HDRLEN; |
603 | } |
604 | |
605 | /** |
606 | * nlmsg_attrdata - head of attributes data |
607 | * @nlh: netlink message header |
608 | * @hdrlen: length of family specific header |
609 | */ |
610 | static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh, |
611 | int hdrlen) |
612 | { |
613 | unsigned char *data = nlmsg_data(nlh); |
614 | return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen)); |
615 | } |
616 | |
617 | /** |
618 | * nlmsg_attrlen - length of attributes data |
619 | * @nlh: netlink message header |
620 | * @hdrlen: length of family specific header |
621 | */ |
622 | static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen) |
623 | { |
624 | return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen); |
625 | } |
626 | |
627 | /** |
628 | * nlmsg_ok - check if the netlink message fits into the remaining bytes |
629 | * @nlh: netlink message header |
630 | * @remaining: number of bytes remaining in message stream |
631 | */ |
632 | static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining) |
633 | { |
634 | return (remaining >= (int) sizeof(struct nlmsghdr) && |
635 | nlh->nlmsg_len >= sizeof(struct nlmsghdr) && |
636 | nlh->nlmsg_len <= remaining); |
637 | } |
638 | |
639 | /** |
640 | * nlmsg_next - next netlink message in message stream |
641 | * @nlh: netlink message header |
642 | * @remaining: number of bytes remaining in message stream |
643 | * |
644 | * Returns the next netlink message in the message stream and |
645 | * decrements remaining by the size of the current message. |
646 | */ |
647 | static inline struct nlmsghdr * |
648 | nlmsg_next(const struct nlmsghdr *nlh, int *remaining) |
649 | { |
650 | int totlen = NLMSG_ALIGN(nlh->nlmsg_len); |
651 | |
652 | *remaining -= totlen; |
653 | |
654 | return (struct nlmsghdr *) ((unsigned char *) nlh + totlen); |
655 | } |
656 | |
657 | /** |
658 | * nla_parse - Parse a stream of attributes into a tb buffer |
659 | * @tb: destination array with maxtype+1 elements |
660 | * @maxtype: maximum attribute type to be expected |
661 | * @head: head of attribute stream |
662 | * @len: length of attribute stream |
663 | * @policy: validation policy |
664 | * @extack: extended ACK pointer |
665 | * |
666 | * Parses a stream of attributes and stores a pointer to each attribute in |
667 | * the tb array accessible via the attribute type. Attributes with a type |
668 | * exceeding maxtype will be rejected, policy must be specified, attributes |
669 | * will be validated in the strictest way possible. |
670 | * |
671 | * Returns 0 on success or a negative error code. |
672 | */ |
673 | static inline int nla_parse(struct nlattr **tb, int maxtype, |
674 | const struct nlattr *head, int len, |
675 | const struct nla_policy *policy, |
676 | struct netlink_ext_ack *extack) |
677 | { |
678 | return __nla_parse(tb, maxtype, head, len, policy, |
679 | NL_VALIDATE_STRICT, extack); |
680 | } |
681 | |
682 | /** |
683 | * nla_parse_deprecated - Parse a stream of attributes into a tb buffer |
684 | * @tb: destination array with maxtype+1 elements |
685 | * @maxtype: maximum attribute type to be expected |
686 | * @head: head of attribute stream |
687 | * @len: length of attribute stream |
688 | * @policy: validation policy |
689 | * @extack: extended ACK pointer |
690 | * |
691 | * Parses a stream of attributes and stores a pointer to each attribute in |
692 | * the tb array accessible via the attribute type. Attributes with a type |
693 | * exceeding maxtype will be ignored and attributes from the policy are not |
694 | * always strictly validated (only for new attributes). |
695 | * |
696 | * Returns 0 on success or a negative error code. |
697 | */ |
698 | static inline int nla_parse_deprecated(struct nlattr **tb, int maxtype, |
699 | const struct nlattr *head, int len, |
700 | const struct nla_policy *policy, |
701 | struct netlink_ext_ack *extack) |
702 | { |
703 | return __nla_parse(tb, maxtype, head, len, policy, |
704 | validate: NL_VALIDATE_LIBERAL, extack); |
705 | } |
706 | |
707 | /** |
708 | * nla_parse_deprecated_strict - Parse a stream of attributes into a tb buffer |
709 | * @tb: destination array with maxtype+1 elements |
710 | * @maxtype: maximum attribute type to be expected |
711 | * @head: head of attribute stream |
712 | * @len: length of attribute stream |
713 | * @policy: validation policy |
714 | * @extack: extended ACK pointer |
715 | * |
716 | * Parses a stream of attributes and stores a pointer to each attribute in |
717 | * the tb array accessible via the attribute type. Attributes with a type |
718 | * exceeding maxtype will be rejected as well as trailing data, but the |
719 | * policy is not completely strictly validated (only for new attributes). |
720 | * |
721 | * Returns 0 on success or a negative error code. |
722 | */ |
723 | static inline int nla_parse_deprecated_strict(struct nlattr **tb, int maxtype, |
724 | const struct nlattr *head, |
725 | int len, |
726 | const struct nla_policy *policy, |
727 | struct netlink_ext_ack *extack) |
728 | { |
729 | return __nla_parse(tb, maxtype, head, len, policy, |
730 | NL_VALIDATE_DEPRECATED_STRICT, extack); |
731 | } |
732 | |
733 | /** |
734 | * __nlmsg_parse - parse attributes of a netlink message |
735 | * @nlh: netlink message header |
736 | * @hdrlen: length of family specific header |
737 | * @tb: destination array with maxtype+1 elements |
738 | * @maxtype: maximum attribute type to be expected |
739 | * @policy: validation policy |
740 | * @validate: validation strictness |
741 | * @extack: extended ACK report struct |
742 | * |
743 | * See nla_parse() |
744 | */ |
745 | static inline int __nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, |
746 | struct nlattr *tb[], int maxtype, |
747 | const struct nla_policy *policy, |
748 | unsigned int validate, |
749 | struct netlink_ext_ack *extack) |
750 | { |
751 | if (nlh->nlmsg_len < nlmsg_msg_size(payload: hdrlen)) { |
752 | NL_SET_ERR_MSG(extack, "Invalid header length" ); |
753 | return -EINVAL; |
754 | } |
755 | |
756 | return __nla_parse(tb, maxtype, head: nlmsg_attrdata(nlh, hdrlen), |
757 | len: nlmsg_attrlen(nlh, hdrlen), policy, validate, |
758 | extack); |
759 | } |
760 | |
761 | /** |
762 | * nlmsg_parse - parse attributes of a netlink message |
763 | * @nlh: netlink message header |
764 | * @hdrlen: length of family specific header |
765 | * @tb: destination array with maxtype+1 elements |
766 | * @maxtype: maximum attribute type to be expected |
767 | * @policy: validation policy |
768 | * @extack: extended ACK report struct |
769 | * |
770 | * See nla_parse() |
771 | */ |
772 | static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, |
773 | struct nlattr *tb[], int maxtype, |
774 | const struct nla_policy *policy, |
775 | struct netlink_ext_ack *extack) |
776 | { |
777 | return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy, |
778 | NL_VALIDATE_STRICT, extack); |
779 | } |
780 | |
781 | /** |
782 | * nlmsg_parse_deprecated - parse attributes of a netlink message |
783 | * @nlh: netlink message header |
784 | * @hdrlen: length of family specific header |
785 | * @tb: destination array with maxtype+1 elements |
786 | * @maxtype: maximum attribute type to be expected |
787 | * @policy: validation policy |
788 | * @extack: extended ACK report struct |
789 | * |
790 | * See nla_parse_deprecated() |
791 | */ |
792 | static inline int nlmsg_parse_deprecated(const struct nlmsghdr *nlh, int hdrlen, |
793 | struct nlattr *tb[], int maxtype, |
794 | const struct nla_policy *policy, |
795 | struct netlink_ext_ack *extack) |
796 | { |
797 | return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy, |
798 | validate: NL_VALIDATE_LIBERAL, extack); |
799 | } |
800 | |
801 | /** |
802 | * nlmsg_parse_deprecated_strict - parse attributes of a netlink message |
803 | * @nlh: netlink message header |
804 | * @hdrlen: length of family specific header |
805 | * @tb: destination array with maxtype+1 elements |
806 | * @maxtype: maximum attribute type to be expected |
807 | * @policy: validation policy |
808 | * @extack: extended ACK report struct |
809 | * |
810 | * See nla_parse_deprecated_strict() |
811 | */ |
812 | static inline int |
813 | nlmsg_parse_deprecated_strict(const struct nlmsghdr *nlh, int hdrlen, |
814 | struct nlattr *tb[], int maxtype, |
815 | const struct nla_policy *policy, |
816 | struct netlink_ext_ack *extack) |
817 | { |
818 | return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy, |
819 | NL_VALIDATE_DEPRECATED_STRICT, extack); |
820 | } |
821 | |
822 | /** |
823 | * nlmsg_find_attr - find a specific attribute in a netlink message |
824 | * @nlh: netlink message header |
825 | * @hdrlen: length of familiy specific header |
826 | * @attrtype: type of attribute to look for |
827 | * |
828 | * Returns the first attribute which matches the specified type. |
829 | */ |
830 | static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh, |
831 | int hdrlen, int attrtype) |
832 | { |
833 | return nla_find(head: nlmsg_attrdata(nlh, hdrlen), |
834 | len: nlmsg_attrlen(nlh, hdrlen), attrtype); |
835 | } |
836 | |
837 | /** |
838 | * nla_validate_deprecated - Validate a stream of attributes |
839 | * @head: head of attribute stream |
840 | * @len: length of attribute stream |
841 | * @maxtype: maximum attribute type to be expected |
842 | * @policy: validation policy |
843 | * @extack: extended ACK report struct |
844 | * |
845 | * Validates all attributes in the specified attribute stream against the |
846 | * specified policy. Validation is done in liberal mode. |
847 | * See documenation of struct nla_policy for more details. |
848 | * |
849 | * Returns 0 on success or a negative error code. |
850 | */ |
851 | static inline int nla_validate_deprecated(const struct nlattr *head, int len, |
852 | int maxtype, |
853 | const struct nla_policy *policy, |
854 | struct netlink_ext_ack *extack) |
855 | { |
856 | return __nla_validate(head, len, maxtype, policy, validate: NL_VALIDATE_LIBERAL, |
857 | extack); |
858 | } |
859 | |
860 | /** |
861 | * nla_validate - Validate a stream of attributes |
862 | * @head: head of attribute stream |
863 | * @len: length of attribute stream |
864 | * @maxtype: maximum attribute type to be expected |
865 | * @policy: validation policy |
866 | * @extack: extended ACK report struct |
867 | * |
868 | * Validates all attributes in the specified attribute stream against the |
869 | * specified policy. Validation is done in strict mode. |
870 | * See documenation of struct nla_policy for more details. |
871 | * |
872 | * Returns 0 on success or a negative error code. |
873 | */ |
874 | static inline int nla_validate(const struct nlattr *head, int len, int maxtype, |
875 | const struct nla_policy *policy, |
876 | struct netlink_ext_ack *extack) |
877 | { |
878 | return __nla_validate(head, len, maxtype, policy, NL_VALIDATE_STRICT, |
879 | extack); |
880 | } |
881 | |
882 | /** |
883 | * nlmsg_validate_deprecated - validate a netlink message including attributes |
884 | * @nlh: netlinket message header |
885 | * @hdrlen: length of familiy specific header |
886 | * @maxtype: maximum attribute type to be expected |
887 | * @policy: validation policy |
888 | * @extack: extended ACK report struct |
889 | */ |
890 | static inline int nlmsg_validate_deprecated(const struct nlmsghdr *nlh, |
891 | int hdrlen, int maxtype, |
892 | const struct nla_policy *policy, |
893 | struct netlink_ext_ack *extack) |
894 | { |
895 | if (nlh->nlmsg_len < nlmsg_msg_size(payload: hdrlen)) |
896 | return -EINVAL; |
897 | |
898 | return __nla_validate(head: nlmsg_attrdata(nlh, hdrlen), |
899 | len: nlmsg_attrlen(nlh, hdrlen), maxtype, |
900 | policy, validate: NL_VALIDATE_LIBERAL, extack); |
901 | } |
902 | |
903 | |
904 | |
905 | /** |
906 | * nlmsg_report - need to report back to application? |
907 | * @nlh: netlink message header |
908 | * |
909 | * Returns 1 if a report back to the application is requested. |
910 | */ |
911 | static inline int nlmsg_report(const struct nlmsghdr *nlh) |
912 | { |
913 | return nlh ? !!(nlh->nlmsg_flags & NLM_F_ECHO) : 0; |
914 | } |
915 | |
916 | /** |
917 | * nlmsg_seq - return the seq number of netlink message |
918 | * @nlh: netlink message header |
919 | * |
920 | * Returns 0 if netlink message is NULL |
921 | */ |
922 | static inline u32 nlmsg_seq(const struct nlmsghdr *nlh) |
923 | { |
924 | return nlh ? nlh->nlmsg_seq : 0; |
925 | } |
926 | |
927 | /** |
928 | * nlmsg_for_each_attr - iterate over a stream of attributes |
929 | * @pos: loop counter, set to current attribute |
930 | * @nlh: netlink message header |
931 | * @hdrlen: length of familiy specific header |
932 | * @rem: initialized to len, holds bytes currently remaining in stream |
933 | */ |
934 | #define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \ |
935 | nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \ |
936 | nlmsg_attrlen(nlh, hdrlen), rem) |
937 | |
938 | /** |
939 | * nlmsg_put - Add a new netlink message to an skb |
940 | * @skb: socket buffer to store message in |
941 | * @portid: netlink PORTID of requesting application |
942 | * @seq: sequence number of message |
943 | * @type: message type |
944 | * @payload: length of message payload |
945 | * @flags: message flags |
946 | * |
947 | * Returns NULL if the tailroom of the skb is insufficient to store |
948 | * the message header and payload. |
949 | */ |
950 | static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, |
951 | int type, int payload, int flags) |
952 | { |
953 | if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload))) |
954 | return NULL; |
955 | |
956 | return __nlmsg_put(skb, portid, seq, type, len: payload, flags); |
957 | } |
958 | |
959 | /** |
960 | * nlmsg_append - Add more data to a nlmsg in a skb |
961 | * @skb: socket buffer to store message in |
962 | * @size: length of message payload |
963 | * |
964 | * Append data to an existing nlmsg, used when constructing a message |
965 | * with multiple fixed-format headers (which is rare). |
966 | * Returns NULL if the tailroom of the skb is insufficient to store |
967 | * the extra payload. |
968 | */ |
969 | static inline void *nlmsg_append(struct sk_buff *skb, u32 size) |
970 | { |
971 | if (unlikely(skb_tailroom(skb) < NLMSG_ALIGN(size))) |
972 | return NULL; |
973 | |
974 | if (NLMSG_ALIGN(size) - size) |
975 | memset(skb_tail_pointer(skb) + size, 0, |
976 | NLMSG_ALIGN(size) - size); |
977 | return __skb_put(skb, NLMSG_ALIGN(size)); |
978 | } |
979 | |
980 | /** |
981 | * nlmsg_put_answer - Add a new callback based netlink message to an skb |
982 | * @skb: socket buffer to store message in |
983 | * @cb: netlink callback |
984 | * @type: message type |
985 | * @payload: length of message payload |
986 | * @flags: message flags |
987 | * |
988 | * Returns NULL if the tailroom of the skb is insufficient to store |
989 | * the message header and payload. |
990 | */ |
991 | static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb, |
992 | struct netlink_callback *cb, |
993 | int type, int payload, |
994 | int flags) |
995 | { |
996 | return nlmsg_put(skb, NETLINK_CB(cb->skb).portid, seq: cb->nlh->nlmsg_seq, |
997 | type, payload, flags); |
998 | } |
999 | |
1000 | /** |
1001 | * nlmsg_new - Allocate a new netlink message |
1002 | * @payload: size of the message payload |
1003 | * @flags: the type of memory to allocate. |
1004 | * |
1005 | * Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known |
1006 | * and a good default is needed. |
1007 | */ |
1008 | static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags) |
1009 | { |
1010 | return alloc_skb(size: nlmsg_total_size(payload), priority: flags); |
1011 | } |
1012 | |
1013 | /** |
1014 | * nlmsg_new_large - Allocate a new netlink message with non-contiguous |
1015 | * physical memory |
1016 | * @payload: size of the message payload |
1017 | * |
1018 | * The allocated skb is unable to have frag page for shinfo->frags*, |
1019 | * as the NULL setting for skb->head in netlink_skb_destructor() will |
1020 | * bypass most of the handling in skb_release_data() |
1021 | */ |
1022 | static inline struct sk_buff *nlmsg_new_large(size_t payload) |
1023 | { |
1024 | return netlink_alloc_large_skb(size: nlmsg_total_size(payload), broadcast: 0); |
1025 | } |
1026 | |
1027 | /** |
1028 | * nlmsg_end - Finalize a netlink message |
1029 | * @skb: socket buffer the message is stored in |
1030 | * @nlh: netlink message header |
1031 | * |
1032 | * Corrects the netlink message header to include the appeneded |
1033 | * attributes. Only necessary if attributes have been added to |
1034 | * the message. |
1035 | */ |
1036 | static inline void nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh) |
1037 | { |
1038 | nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh; |
1039 | } |
1040 | |
1041 | /** |
1042 | * nlmsg_get_pos - return current position in netlink message |
1043 | * @skb: socket buffer the message is stored in |
1044 | * |
1045 | * Returns a pointer to the current tail of the message. |
1046 | */ |
1047 | static inline void *nlmsg_get_pos(struct sk_buff *skb) |
1048 | { |
1049 | return skb_tail_pointer(skb); |
1050 | } |
1051 | |
1052 | /** |
1053 | * nlmsg_trim - Trim message to a mark |
1054 | * @skb: socket buffer the message is stored in |
1055 | * @mark: mark to trim to |
1056 | * |
1057 | * Trims the message to the provided mark. |
1058 | */ |
1059 | static inline void nlmsg_trim(struct sk_buff *skb, const void *mark) |
1060 | { |
1061 | if (mark) { |
1062 | WARN_ON((unsigned char *) mark < skb->data); |
1063 | skb_trim(skb, len: (unsigned char *) mark - skb->data); |
1064 | } |
1065 | } |
1066 | |
1067 | /** |
1068 | * nlmsg_cancel - Cancel construction of a netlink message |
1069 | * @skb: socket buffer the message is stored in |
1070 | * @nlh: netlink message header |
1071 | * |
1072 | * Removes the complete netlink message including all |
1073 | * attributes from the socket buffer again. |
1074 | */ |
1075 | static inline void nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh) |
1076 | { |
1077 | nlmsg_trim(skb, mark: nlh); |
1078 | } |
1079 | |
1080 | /** |
1081 | * nlmsg_free - free a netlink message |
1082 | * @skb: socket buffer of netlink message |
1083 | */ |
1084 | static inline void nlmsg_free(struct sk_buff *skb) |
1085 | { |
1086 | kfree_skb(skb); |
1087 | } |
1088 | |
1089 | /** |
1090 | * nlmsg_multicast_filtered - multicast a netlink message with filter function |
1091 | * @sk: netlink socket to spread messages to |
1092 | * @skb: netlink message as socket buffer |
1093 | * @portid: own netlink portid to avoid sending to yourself |
1094 | * @group: multicast group id |
1095 | * @flags: allocation flags |
1096 | * @filter: filter function |
1097 | * @filter_data: filter function private data |
1098 | * |
1099 | * Return: 0 on success, negative error code for failure. |
1100 | */ |
1101 | static inline int nlmsg_multicast_filtered(struct sock *sk, struct sk_buff *skb, |
1102 | u32 portid, unsigned int group, |
1103 | gfp_t flags, |
1104 | netlink_filter_fn filter, |
1105 | void *filter_data) |
1106 | { |
1107 | int err; |
1108 | |
1109 | NETLINK_CB(skb).dst_group = group; |
1110 | |
1111 | err = netlink_broadcast_filtered(ssk: sk, skb, portid, group, allocation: flags, |
1112 | filter, filter_data); |
1113 | if (err > 0) |
1114 | err = 0; |
1115 | |
1116 | return err; |
1117 | } |
1118 | |
1119 | /** |
1120 | * nlmsg_multicast - multicast a netlink message |
1121 | * @sk: netlink socket to spread messages to |
1122 | * @skb: netlink message as socket buffer |
1123 | * @portid: own netlink portid to avoid sending to yourself |
1124 | * @group: multicast group id |
1125 | * @flags: allocation flags |
1126 | */ |
1127 | static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb, |
1128 | u32 portid, unsigned int group, gfp_t flags) |
1129 | { |
1130 | return nlmsg_multicast_filtered(sk, skb, portid, group, flags, |
1131 | NULL, NULL); |
1132 | } |
1133 | |
1134 | /** |
1135 | * nlmsg_unicast - unicast a netlink message |
1136 | * @sk: netlink socket to spread message to |
1137 | * @skb: netlink message as socket buffer |
1138 | * @portid: netlink portid of the destination socket |
1139 | */ |
1140 | static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 portid) |
1141 | { |
1142 | int err; |
1143 | |
1144 | err = netlink_unicast(ssk: sk, skb, portid, MSG_DONTWAIT); |
1145 | if (err > 0) |
1146 | err = 0; |
1147 | |
1148 | return err; |
1149 | } |
1150 | |
1151 | /** |
1152 | * nlmsg_for_each_msg - iterate over a stream of messages |
1153 | * @pos: loop counter, set to current message |
1154 | * @head: head of message stream |
1155 | * @len: length of message stream |
1156 | * @rem: initialized to len, holds bytes currently remaining in stream |
1157 | */ |
1158 | #define nlmsg_for_each_msg(pos, head, len, rem) \ |
1159 | for (pos = head, rem = len; \ |
1160 | nlmsg_ok(pos, rem); \ |
1161 | pos = nlmsg_next(pos, &(rem))) |
1162 | |
1163 | /** |
1164 | * nl_dump_check_consistent - check if sequence is consistent and advertise if not |
1165 | * @cb: netlink callback structure that stores the sequence number |
1166 | * @nlh: netlink message header to write the flag to |
1167 | * |
1168 | * This function checks if the sequence (generation) number changed during dump |
1169 | * and if it did, advertises it in the netlink message header. |
1170 | * |
1171 | * The correct way to use it is to set cb->seq to the generation counter when |
1172 | * all locks for dumping have been acquired, and then call this function for |
1173 | * each message that is generated. |
1174 | * |
1175 | * Note that due to initialisation concerns, 0 is an invalid sequence number |
1176 | * and must not be used by code that uses this functionality. |
1177 | */ |
1178 | static inline void |
1179 | nl_dump_check_consistent(struct netlink_callback *cb, |
1180 | struct nlmsghdr *nlh) |
1181 | { |
1182 | if (cb->prev_seq && cb->seq != cb->prev_seq) |
1183 | nlh->nlmsg_flags |= NLM_F_DUMP_INTR; |
1184 | cb->prev_seq = cb->seq; |
1185 | } |
1186 | |
1187 | /************************************************************************** |
1188 | * Netlink Attributes |
1189 | **************************************************************************/ |
1190 | |
1191 | /** |
1192 | * nla_attr_size - length of attribute not including padding |
1193 | * @payload: length of payload |
1194 | */ |
1195 | static inline int nla_attr_size(int payload) |
1196 | { |
1197 | return NLA_HDRLEN + payload; |
1198 | } |
1199 | |
1200 | /** |
1201 | * nla_total_size - total length of attribute including padding |
1202 | * @payload: length of payload |
1203 | */ |
1204 | static inline int nla_total_size(int payload) |
1205 | { |
1206 | return NLA_ALIGN(nla_attr_size(payload)); |
1207 | } |
1208 | |
1209 | /** |
1210 | * nla_padlen - length of padding at the tail of attribute |
1211 | * @payload: length of payload |
1212 | */ |
1213 | static inline int nla_padlen(int payload) |
1214 | { |
1215 | return nla_total_size(payload) - nla_attr_size(payload); |
1216 | } |
1217 | |
1218 | /** |
1219 | * nla_type - attribute type |
1220 | * @nla: netlink attribute |
1221 | */ |
1222 | static inline int nla_type(const struct nlattr *nla) |
1223 | { |
1224 | return nla->nla_type & NLA_TYPE_MASK; |
1225 | } |
1226 | |
1227 | /** |
1228 | * nla_data - head of payload |
1229 | * @nla: netlink attribute |
1230 | */ |
1231 | static inline void *nla_data(const struct nlattr *nla) |
1232 | { |
1233 | return (char *) nla + NLA_HDRLEN; |
1234 | } |
1235 | |
1236 | /** |
1237 | * nla_len - length of payload |
1238 | * @nla: netlink attribute |
1239 | */ |
1240 | static inline u16 nla_len(const struct nlattr *nla) |
1241 | { |
1242 | return nla->nla_len - NLA_HDRLEN; |
1243 | } |
1244 | |
1245 | /** |
1246 | * nla_ok - check if the netlink attribute fits into the remaining bytes |
1247 | * @nla: netlink attribute |
1248 | * @remaining: number of bytes remaining in attribute stream |
1249 | */ |
1250 | static inline int nla_ok(const struct nlattr *nla, int remaining) |
1251 | { |
1252 | return remaining >= (int) sizeof(*nla) && |
1253 | nla->nla_len >= sizeof(*nla) && |
1254 | nla->nla_len <= remaining; |
1255 | } |
1256 | |
1257 | /** |
1258 | * nla_next - next netlink attribute in attribute stream |
1259 | * @nla: netlink attribute |
1260 | * @remaining: number of bytes remaining in attribute stream |
1261 | * |
1262 | * Returns the next netlink attribute in the attribute stream and |
1263 | * decrements remaining by the size of the current attribute. |
1264 | */ |
1265 | static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining) |
1266 | { |
1267 | unsigned int totlen = NLA_ALIGN(nla->nla_len); |
1268 | |
1269 | *remaining -= totlen; |
1270 | return (struct nlattr *) ((char *) nla + totlen); |
1271 | } |
1272 | |
1273 | /** |
1274 | * nla_find_nested - find attribute in a set of nested attributes |
1275 | * @nla: attribute containing the nested attributes |
1276 | * @attrtype: type of attribute to look for |
1277 | * |
1278 | * Returns the first attribute which matches the specified type. |
1279 | */ |
1280 | static inline struct nlattr * |
1281 | nla_find_nested(const struct nlattr *nla, int attrtype) |
1282 | { |
1283 | return nla_find(head: nla_data(nla), len: nla_len(nla), attrtype); |
1284 | } |
1285 | |
1286 | /** |
1287 | * nla_parse_nested - parse nested attributes |
1288 | * @tb: destination array with maxtype+1 elements |
1289 | * @maxtype: maximum attribute type to be expected |
1290 | * @nla: attribute containing the nested attributes |
1291 | * @policy: validation policy |
1292 | * @extack: extended ACK report struct |
1293 | * |
1294 | * See nla_parse() |
1295 | */ |
1296 | static inline int nla_parse_nested(struct nlattr *tb[], int maxtype, |
1297 | const struct nlattr *nla, |
1298 | const struct nla_policy *policy, |
1299 | struct netlink_ext_ack *extack) |
1300 | { |
1301 | if (!(nla->nla_type & NLA_F_NESTED)) { |
1302 | NL_SET_ERR_MSG_ATTR(extack, nla, "NLA_F_NESTED is missing" ); |
1303 | return -EINVAL; |
1304 | } |
1305 | |
1306 | return __nla_parse(tb, maxtype, head: nla_data(nla), len: nla_len(nla), policy, |
1307 | NL_VALIDATE_STRICT, extack); |
1308 | } |
1309 | |
1310 | /** |
1311 | * nla_parse_nested_deprecated - parse nested attributes |
1312 | * @tb: destination array with maxtype+1 elements |
1313 | * @maxtype: maximum attribute type to be expected |
1314 | * @nla: attribute containing the nested attributes |
1315 | * @policy: validation policy |
1316 | * @extack: extended ACK report struct |
1317 | * |
1318 | * See nla_parse_deprecated() |
1319 | */ |
1320 | static inline int nla_parse_nested_deprecated(struct nlattr *tb[], int maxtype, |
1321 | const struct nlattr *nla, |
1322 | const struct nla_policy *policy, |
1323 | struct netlink_ext_ack *extack) |
1324 | { |
1325 | return __nla_parse(tb, maxtype, head: nla_data(nla), len: nla_len(nla), policy, |
1326 | validate: NL_VALIDATE_LIBERAL, extack); |
1327 | } |
1328 | |
1329 | /** |
1330 | * nla_put_u8 - Add a u8 netlink attribute to a socket buffer |
1331 | * @skb: socket buffer to add attribute to |
1332 | * @attrtype: attribute type |
1333 | * @value: numeric value |
1334 | */ |
1335 | static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value) |
1336 | { |
1337 | /* temporary variables to work around GCC PR81715 with asan-stack=1 */ |
1338 | u8 tmp = value; |
1339 | |
1340 | return nla_put(skb, attrtype, attrlen: sizeof(u8), data: &tmp); |
1341 | } |
1342 | |
1343 | /** |
1344 | * nla_put_u16 - Add a u16 netlink attribute to a socket buffer |
1345 | * @skb: socket buffer to add attribute to |
1346 | * @attrtype: attribute type |
1347 | * @value: numeric value |
1348 | */ |
1349 | static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value) |
1350 | { |
1351 | u16 tmp = value; |
1352 | |
1353 | return nla_put(skb, attrtype, attrlen: sizeof(u16), data: &tmp); |
1354 | } |
1355 | |
1356 | /** |
1357 | * nla_put_be16 - Add a __be16 netlink attribute to a socket buffer |
1358 | * @skb: socket buffer to add attribute to |
1359 | * @attrtype: attribute type |
1360 | * @value: numeric value |
1361 | */ |
1362 | static inline int nla_put_be16(struct sk_buff *skb, int attrtype, __be16 value) |
1363 | { |
1364 | __be16 tmp = value; |
1365 | |
1366 | return nla_put(skb, attrtype, attrlen: sizeof(__be16), data: &tmp); |
1367 | } |
1368 | |
1369 | /** |
1370 | * nla_put_net16 - Add 16-bit network byte order netlink attribute to a socket buffer |
1371 | * @skb: socket buffer to add attribute to |
1372 | * @attrtype: attribute type |
1373 | * @value: numeric value |
1374 | */ |
1375 | static inline int nla_put_net16(struct sk_buff *skb, int attrtype, __be16 value) |
1376 | { |
1377 | __be16 tmp = value; |
1378 | |
1379 | return nla_put_be16(skb, attrtype: attrtype | NLA_F_NET_BYTEORDER, value: tmp); |
1380 | } |
1381 | |
1382 | /** |
1383 | * nla_put_le16 - Add a __le16 netlink attribute to a socket buffer |
1384 | * @skb: socket buffer to add attribute to |
1385 | * @attrtype: attribute type |
1386 | * @value: numeric value |
1387 | */ |
1388 | static inline int nla_put_le16(struct sk_buff *skb, int attrtype, __le16 value) |
1389 | { |
1390 | __le16 tmp = value; |
1391 | |
1392 | return nla_put(skb, attrtype, attrlen: sizeof(__le16), data: &tmp); |
1393 | } |
1394 | |
1395 | /** |
1396 | * nla_put_u32 - Add a u32 netlink attribute to a socket buffer |
1397 | * @skb: socket buffer to add attribute to |
1398 | * @attrtype: attribute type |
1399 | * @value: numeric value |
1400 | */ |
1401 | static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value) |
1402 | { |
1403 | u32 tmp = value; |
1404 | |
1405 | return nla_put(skb, attrtype, attrlen: sizeof(u32), data: &tmp); |
1406 | } |
1407 | |
1408 | /** |
1409 | * nla_put_uint - Add a variable-size unsigned int to a socket buffer |
1410 | * @skb: socket buffer to add attribute to |
1411 | * @attrtype: attribute type |
1412 | * @value: numeric value |
1413 | */ |
1414 | static inline int nla_put_uint(struct sk_buff *skb, int attrtype, u64 value) |
1415 | { |
1416 | u64 tmp64 = value; |
1417 | u32 tmp32 = value; |
1418 | |
1419 | if (tmp64 == tmp32) |
1420 | return nla_put_u32(skb, attrtype, value: tmp32); |
1421 | return nla_put(skb, attrtype, attrlen: sizeof(u64), data: &tmp64); |
1422 | } |
1423 | |
1424 | /** |
1425 | * nla_put_be32 - Add a __be32 netlink attribute to a socket buffer |
1426 | * @skb: socket buffer to add attribute to |
1427 | * @attrtype: attribute type |
1428 | * @value: numeric value |
1429 | */ |
1430 | static inline int nla_put_be32(struct sk_buff *skb, int attrtype, __be32 value) |
1431 | { |
1432 | __be32 tmp = value; |
1433 | |
1434 | return nla_put(skb, attrtype, attrlen: sizeof(__be32), data: &tmp); |
1435 | } |
1436 | |
1437 | /** |
1438 | * nla_put_net32 - Add 32-bit network byte order netlink attribute to a socket buffer |
1439 | * @skb: socket buffer to add attribute to |
1440 | * @attrtype: attribute type |
1441 | * @value: numeric value |
1442 | */ |
1443 | static inline int nla_put_net32(struct sk_buff *skb, int attrtype, __be32 value) |
1444 | { |
1445 | __be32 tmp = value; |
1446 | |
1447 | return nla_put_be32(skb, attrtype: attrtype | NLA_F_NET_BYTEORDER, value: tmp); |
1448 | } |
1449 | |
1450 | /** |
1451 | * nla_put_le32 - Add a __le32 netlink attribute to a socket buffer |
1452 | * @skb: socket buffer to add attribute to |
1453 | * @attrtype: attribute type |
1454 | * @value: numeric value |
1455 | */ |
1456 | static inline int nla_put_le32(struct sk_buff *skb, int attrtype, __le32 value) |
1457 | { |
1458 | __le32 tmp = value; |
1459 | |
1460 | return nla_put(skb, attrtype, attrlen: sizeof(__le32), data: &tmp); |
1461 | } |
1462 | |
1463 | /** |
1464 | * nla_put_u64_64bit - Add a u64 netlink attribute to a skb and align it |
1465 | * @skb: socket buffer to add attribute to |
1466 | * @attrtype: attribute type |
1467 | * @value: numeric value |
1468 | * @padattr: attribute type for the padding |
1469 | */ |
1470 | static inline int nla_put_u64_64bit(struct sk_buff *skb, int attrtype, |
1471 | u64 value, int padattr) |
1472 | { |
1473 | u64 tmp = value; |
1474 | |
1475 | return nla_put_64bit(skb, attrtype, attrlen: sizeof(u64), data: &tmp, padattr); |
1476 | } |
1477 | |
1478 | /** |
1479 | * nla_put_be64 - Add a __be64 netlink attribute to a socket buffer and align it |
1480 | * @skb: socket buffer to add attribute to |
1481 | * @attrtype: attribute type |
1482 | * @value: numeric value |
1483 | * @padattr: attribute type for the padding |
1484 | */ |
1485 | static inline int nla_put_be64(struct sk_buff *skb, int attrtype, __be64 value, |
1486 | int padattr) |
1487 | { |
1488 | __be64 tmp = value; |
1489 | |
1490 | return nla_put_64bit(skb, attrtype, attrlen: sizeof(__be64), data: &tmp, padattr); |
1491 | } |
1492 | |
1493 | /** |
1494 | * nla_put_net64 - Add 64-bit network byte order nlattr to a skb and align it |
1495 | * @skb: socket buffer to add attribute to |
1496 | * @attrtype: attribute type |
1497 | * @value: numeric value |
1498 | * @padattr: attribute type for the padding |
1499 | */ |
1500 | static inline int nla_put_net64(struct sk_buff *skb, int attrtype, __be64 value, |
1501 | int padattr) |
1502 | { |
1503 | __be64 tmp = value; |
1504 | |
1505 | return nla_put_be64(skb, attrtype: attrtype | NLA_F_NET_BYTEORDER, value: tmp, |
1506 | padattr); |
1507 | } |
1508 | |
1509 | /** |
1510 | * nla_put_le64 - Add a __le64 netlink attribute to a socket buffer and align it |
1511 | * @skb: socket buffer to add attribute to |
1512 | * @attrtype: attribute type |
1513 | * @value: numeric value |
1514 | * @padattr: attribute type for the padding |
1515 | */ |
1516 | static inline int nla_put_le64(struct sk_buff *skb, int attrtype, __le64 value, |
1517 | int padattr) |
1518 | { |
1519 | __le64 tmp = value; |
1520 | |
1521 | return nla_put_64bit(skb, attrtype, attrlen: sizeof(__le64), data: &tmp, padattr); |
1522 | } |
1523 | |
1524 | /** |
1525 | * nla_put_s8 - Add a s8 netlink attribute to a socket buffer |
1526 | * @skb: socket buffer to add attribute to |
1527 | * @attrtype: attribute type |
1528 | * @value: numeric value |
1529 | */ |
1530 | static inline int nla_put_s8(struct sk_buff *skb, int attrtype, s8 value) |
1531 | { |
1532 | s8 tmp = value; |
1533 | |
1534 | return nla_put(skb, attrtype, attrlen: sizeof(s8), data: &tmp); |
1535 | } |
1536 | |
1537 | /** |
1538 | * nla_put_s16 - Add a s16 netlink attribute to a socket buffer |
1539 | * @skb: socket buffer to add attribute to |
1540 | * @attrtype: attribute type |
1541 | * @value: numeric value |
1542 | */ |
1543 | static inline int nla_put_s16(struct sk_buff *skb, int attrtype, s16 value) |
1544 | { |
1545 | s16 tmp = value; |
1546 | |
1547 | return nla_put(skb, attrtype, attrlen: sizeof(s16), data: &tmp); |
1548 | } |
1549 | |
1550 | /** |
1551 | * nla_put_s32 - Add a s32 netlink attribute to a socket buffer |
1552 | * @skb: socket buffer to add attribute to |
1553 | * @attrtype: attribute type |
1554 | * @value: numeric value |
1555 | */ |
1556 | static inline int nla_put_s32(struct sk_buff *skb, int attrtype, s32 value) |
1557 | { |
1558 | s32 tmp = value; |
1559 | |
1560 | return nla_put(skb, attrtype, attrlen: sizeof(s32), data: &tmp); |
1561 | } |
1562 | |
1563 | /** |
1564 | * nla_put_s64 - Add a s64 netlink attribute to a socket buffer and align it |
1565 | * @skb: socket buffer to add attribute to |
1566 | * @attrtype: attribute type |
1567 | * @value: numeric value |
1568 | * @padattr: attribute type for the padding |
1569 | */ |
1570 | static inline int nla_put_s64(struct sk_buff *skb, int attrtype, s64 value, |
1571 | int padattr) |
1572 | { |
1573 | s64 tmp = value; |
1574 | |
1575 | return nla_put_64bit(skb, attrtype, attrlen: sizeof(s64), data: &tmp, padattr); |
1576 | } |
1577 | |
1578 | /** |
1579 | * nla_put_sint - Add a variable-size signed int to a socket buffer |
1580 | * @skb: socket buffer to add attribute to |
1581 | * @attrtype: attribute type |
1582 | * @value: numeric value |
1583 | */ |
1584 | static inline int nla_put_sint(struct sk_buff *skb, int attrtype, s64 value) |
1585 | { |
1586 | s64 tmp64 = value; |
1587 | s32 tmp32 = value; |
1588 | |
1589 | if (tmp64 == tmp32) |
1590 | return nla_put_s32(skb, attrtype, value: tmp32); |
1591 | return nla_put(skb, attrtype, attrlen: sizeof(s64), data: &tmp64); |
1592 | } |
1593 | |
1594 | /** |
1595 | * nla_put_string - Add a string netlink attribute to a socket buffer |
1596 | * @skb: socket buffer to add attribute to |
1597 | * @attrtype: attribute type |
1598 | * @str: NUL terminated string |
1599 | */ |
1600 | static inline int nla_put_string(struct sk_buff *skb, int attrtype, |
1601 | const char *str) |
1602 | { |
1603 | return nla_put(skb, attrtype, strlen(str) + 1, data: str); |
1604 | } |
1605 | |
1606 | /** |
1607 | * nla_put_flag - Add a flag netlink attribute to a socket buffer |
1608 | * @skb: socket buffer to add attribute to |
1609 | * @attrtype: attribute type |
1610 | */ |
1611 | static inline int nla_put_flag(struct sk_buff *skb, int attrtype) |
1612 | { |
1613 | return nla_put(skb, attrtype, attrlen: 0, NULL); |
1614 | } |
1615 | |
1616 | /** |
1617 | * nla_put_msecs - Add a msecs netlink attribute to a skb and align it |
1618 | * @skb: socket buffer to add attribute to |
1619 | * @attrtype: attribute type |
1620 | * @njiffies: number of jiffies to convert to msecs |
1621 | * @padattr: attribute type for the padding |
1622 | */ |
1623 | static inline int nla_put_msecs(struct sk_buff *skb, int attrtype, |
1624 | unsigned long njiffies, int padattr) |
1625 | { |
1626 | u64 tmp = jiffies_to_msecs(j: njiffies); |
1627 | |
1628 | return nla_put_64bit(skb, attrtype, attrlen: sizeof(u64), data: &tmp, padattr); |
1629 | } |
1630 | |
1631 | /** |
1632 | * nla_put_in_addr - Add an IPv4 address netlink attribute to a socket |
1633 | * buffer |
1634 | * @skb: socket buffer to add attribute to |
1635 | * @attrtype: attribute type |
1636 | * @addr: IPv4 address |
1637 | */ |
1638 | static inline int nla_put_in_addr(struct sk_buff *skb, int attrtype, |
1639 | __be32 addr) |
1640 | { |
1641 | __be32 tmp = addr; |
1642 | |
1643 | return nla_put_be32(skb, attrtype, value: tmp); |
1644 | } |
1645 | |
1646 | /** |
1647 | * nla_put_in6_addr - Add an IPv6 address netlink attribute to a socket |
1648 | * buffer |
1649 | * @skb: socket buffer to add attribute to |
1650 | * @attrtype: attribute type |
1651 | * @addr: IPv6 address |
1652 | */ |
1653 | static inline int nla_put_in6_addr(struct sk_buff *skb, int attrtype, |
1654 | const struct in6_addr *addr) |
1655 | { |
1656 | return nla_put(skb, attrtype, attrlen: sizeof(*addr), data: addr); |
1657 | } |
1658 | |
1659 | /** |
1660 | * nla_put_bitfield32 - Add a bitfield32 netlink attribute to a socket buffer |
1661 | * @skb: socket buffer to add attribute to |
1662 | * @attrtype: attribute type |
1663 | * @value: value carrying bits |
1664 | * @selector: selector of valid bits |
1665 | */ |
1666 | static inline int nla_put_bitfield32(struct sk_buff *skb, int attrtype, |
1667 | __u32 value, __u32 selector) |
1668 | { |
1669 | struct nla_bitfield32 tmp = { value, selector, }; |
1670 | |
1671 | return nla_put(skb, attrtype, attrlen: sizeof(tmp), data: &tmp); |
1672 | } |
1673 | |
1674 | /** |
1675 | * nla_get_u32 - return payload of u32 attribute |
1676 | * @nla: u32 netlink attribute |
1677 | */ |
1678 | static inline u32 nla_get_u32(const struct nlattr *nla) |
1679 | { |
1680 | return *(u32 *) nla_data(nla); |
1681 | } |
1682 | |
1683 | /** |
1684 | * nla_get_be32 - return payload of __be32 attribute |
1685 | * @nla: __be32 netlink attribute |
1686 | */ |
1687 | static inline __be32 nla_get_be32(const struct nlattr *nla) |
1688 | { |
1689 | return *(__be32 *) nla_data(nla); |
1690 | } |
1691 | |
1692 | /** |
1693 | * nla_get_le32 - return payload of __le32 attribute |
1694 | * @nla: __le32 netlink attribute |
1695 | */ |
1696 | static inline __le32 nla_get_le32(const struct nlattr *nla) |
1697 | { |
1698 | return *(__le32 *) nla_data(nla); |
1699 | } |
1700 | |
1701 | /** |
1702 | * nla_get_u16 - return payload of u16 attribute |
1703 | * @nla: u16 netlink attribute |
1704 | */ |
1705 | static inline u16 nla_get_u16(const struct nlattr *nla) |
1706 | { |
1707 | return *(u16 *) nla_data(nla); |
1708 | } |
1709 | |
1710 | /** |
1711 | * nla_get_be16 - return payload of __be16 attribute |
1712 | * @nla: __be16 netlink attribute |
1713 | */ |
1714 | static inline __be16 nla_get_be16(const struct nlattr *nla) |
1715 | { |
1716 | return *(__be16 *) nla_data(nla); |
1717 | } |
1718 | |
1719 | /** |
1720 | * nla_get_le16 - return payload of __le16 attribute |
1721 | * @nla: __le16 netlink attribute |
1722 | */ |
1723 | static inline __le16 nla_get_le16(const struct nlattr *nla) |
1724 | { |
1725 | return *(__le16 *) nla_data(nla); |
1726 | } |
1727 | |
1728 | /** |
1729 | * nla_get_u8 - return payload of u8 attribute |
1730 | * @nla: u8 netlink attribute |
1731 | */ |
1732 | static inline u8 nla_get_u8(const struct nlattr *nla) |
1733 | { |
1734 | return *(u8 *) nla_data(nla); |
1735 | } |
1736 | |
1737 | /** |
1738 | * nla_get_u64 - return payload of u64 attribute |
1739 | * @nla: u64 netlink attribute |
1740 | */ |
1741 | static inline u64 nla_get_u64(const struct nlattr *nla) |
1742 | { |
1743 | u64 tmp; |
1744 | |
1745 | nla_memcpy(dest: &tmp, src: nla, count: sizeof(tmp)); |
1746 | |
1747 | return tmp; |
1748 | } |
1749 | |
1750 | /** |
1751 | * nla_get_uint - return payload of uint attribute |
1752 | * @nla: uint netlink attribute |
1753 | */ |
1754 | static inline u64 nla_get_uint(const struct nlattr *nla) |
1755 | { |
1756 | if (nla_len(nla) == sizeof(u32)) |
1757 | return nla_get_u32(nla); |
1758 | return nla_get_u64(nla); |
1759 | } |
1760 | |
1761 | /** |
1762 | * nla_get_be64 - return payload of __be64 attribute |
1763 | * @nla: __be64 netlink attribute |
1764 | */ |
1765 | static inline __be64 nla_get_be64(const struct nlattr *nla) |
1766 | { |
1767 | __be64 tmp; |
1768 | |
1769 | nla_memcpy(dest: &tmp, src: nla, count: sizeof(tmp)); |
1770 | |
1771 | return tmp; |
1772 | } |
1773 | |
1774 | /** |
1775 | * nla_get_le64 - return payload of __le64 attribute |
1776 | * @nla: __le64 netlink attribute |
1777 | */ |
1778 | static inline __le64 nla_get_le64(const struct nlattr *nla) |
1779 | { |
1780 | return *(__le64 *) nla_data(nla); |
1781 | } |
1782 | |
1783 | /** |
1784 | * nla_get_s32 - return payload of s32 attribute |
1785 | * @nla: s32 netlink attribute |
1786 | */ |
1787 | static inline s32 nla_get_s32(const struct nlattr *nla) |
1788 | { |
1789 | return *(s32 *) nla_data(nla); |
1790 | } |
1791 | |
1792 | /** |
1793 | * nla_get_s16 - return payload of s16 attribute |
1794 | * @nla: s16 netlink attribute |
1795 | */ |
1796 | static inline s16 nla_get_s16(const struct nlattr *nla) |
1797 | { |
1798 | return *(s16 *) nla_data(nla); |
1799 | } |
1800 | |
1801 | /** |
1802 | * nla_get_s8 - return payload of s8 attribute |
1803 | * @nla: s8 netlink attribute |
1804 | */ |
1805 | static inline s8 nla_get_s8(const struct nlattr *nla) |
1806 | { |
1807 | return *(s8 *) nla_data(nla); |
1808 | } |
1809 | |
1810 | /** |
1811 | * nla_get_s64 - return payload of s64 attribute |
1812 | * @nla: s64 netlink attribute |
1813 | */ |
1814 | static inline s64 nla_get_s64(const struct nlattr *nla) |
1815 | { |
1816 | s64 tmp; |
1817 | |
1818 | nla_memcpy(dest: &tmp, src: nla, count: sizeof(tmp)); |
1819 | |
1820 | return tmp; |
1821 | } |
1822 | |
1823 | /** |
1824 | * nla_get_sint - return payload of uint attribute |
1825 | * @nla: uint netlink attribute |
1826 | */ |
1827 | static inline s64 nla_get_sint(const struct nlattr *nla) |
1828 | { |
1829 | if (nla_len(nla) == sizeof(s32)) |
1830 | return nla_get_s32(nla); |
1831 | return nla_get_s64(nla); |
1832 | } |
1833 | |
1834 | /** |
1835 | * nla_get_flag - return payload of flag attribute |
1836 | * @nla: flag netlink attribute |
1837 | */ |
1838 | static inline int nla_get_flag(const struct nlattr *nla) |
1839 | { |
1840 | return !!nla; |
1841 | } |
1842 | |
1843 | /** |
1844 | * nla_get_msecs - return payload of msecs attribute |
1845 | * @nla: msecs netlink attribute |
1846 | * |
1847 | * Returns the number of milliseconds in jiffies. |
1848 | */ |
1849 | static inline unsigned long nla_get_msecs(const struct nlattr *nla) |
1850 | { |
1851 | u64 msecs = nla_get_u64(nla); |
1852 | |
1853 | return msecs_to_jiffies(m: (unsigned long) msecs); |
1854 | } |
1855 | |
1856 | /** |
1857 | * nla_get_in_addr - return payload of IPv4 address attribute |
1858 | * @nla: IPv4 address netlink attribute |
1859 | */ |
1860 | static inline __be32 nla_get_in_addr(const struct nlattr *nla) |
1861 | { |
1862 | return *(__be32 *) nla_data(nla); |
1863 | } |
1864 | |
1865 | /** |
1866 | * nla_get_in6_addr - return payload of IPv6 address attribute |
1867 | * @nla: IPv6 address netlink attribute |
1868 | */ |
1869 | static inline struct in6_addr nla_get_in6_addr(const struct nlattr *nla) |
1870 | { |
1871 | struct in6_addr tmp; |
1872 | |
1873 | nla_memcpy(dest: &tmp, src: nla, count: sizeof(tmp)); |
1874 | return tmp; |
1875 | } |
1876 | |
1877 | /** |
1878 | * nla_get_bitfield32 - return payload of 32 bitfield attribute |
1879 | * @nla: nla_bitfield32 attribute |
1880 | */ |
1881 | static inline struct nla_bitfield32 nla_get_bitfield32(const struct nlattr *nla) |
1882 | { |
1883 | struct nla_bitfield32 tmp; |
1884 | |
1885 | nla_memcpy(dest: &tmp, src: nla, count: sizeof(tmp)); |
1886 | return tmp; |
1887 | } |
1888 | |
1889 | /** |
1890 | * nla_memdup - duplicate attribute memory (kmemdup) |
1891 | * @src: netlink attribute to duplicate from |
1892 | * @gfp: GFP mask |
1893 | */ |
1894 | static inline void *nla_memdup(const struct nlattr *src, gfp_t gfp) |
1895 | { |
1896 | return kmemdup(p: nla_data(nla: src), size: nla_len(nla: src), gfp); |
1897 | } |
1898 | |
1899 | /** |
1900 | * nla_nest_start_noflag - Start a new level of nested attributes |
1901 | * @skb: socket buffer to add attributes to |
1902 | * @attrtype: attribute type of container |
1903 | * |
1904 | * This function exists for backward compatibility to use in APIs which never |
1905 | * marked their nest attributes with NLA_F_NESTED flag. New APIs should use |
1906 | * nla_nest_start() which sets the flag. |
1907 | * |
1908 | * Returns the container attribute or NULL on error |
1909 | */ |
1910 | static inline struct nlattr *nla_nest_start_noflag(struct sk_buff *skb, |
1911 | int attrtype) |
1912 | { |
1913 | struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb); |
1914 | |
1915 | if (nla_put(skb, attrtype, attrlen: 0, NULL) < 0) |
1916 | return NULL; |
1917 | |
1918 | return start; |
1919 | } |
1920 | |
1921 | /** |
1922 | * nla_nest_start - Start a new level of nested attributes, with NLA_F_NESTED |
1923 | * @skb: socket buffer to add attributes to |
1924 | * @attrtype: attribute type of container |
1925 | * |
1926 | * Unlike nla_nest_start_noflag(), mark the nest attribute with NLA_F_NESTED |
1927 | * flag. This is the preferred function to use in new code. |
1928 | * |
1929 | * Returns the container attribute or NULL on error |
1930 | */ |
1931 | static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype) |
1932 | { |
1933 | return nla_nest_start_noflag(skb, attrtype: attrtype | NLA_F_NESTED); |
1934 | } |
1935 | |
1936 | /** |
1937 | * nla_nest_end - Finalize nesting of attributes |
1938 | * @skb: socket buffer the attributes are stored in |
1939 | * @start: container attribute |
1940 | * |
1941 | * Corrects the container attribute header to include the all |
1942 | * appeneded attributes. |
1943 | * |
1944 | * Returns the total data length of the skb. |
1945 | */ |
1946 | static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start) |
1947 | { |
1948 | start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start; |
1949 | return skb->len; |
1950 | } |
1951 | |
1952 | /** |
1953 | * nla_nest_cancel - Cancel nesting of attributes |
1954 | * @skb: socket buffer the message is stored in |
1955 | * @start: container attribute |
1956 | * |
1957 | * Removes the container attribute and including all nested |
1958 | * attributes. Returns -EMSGSIZE |
1959 | */ |
1960 | static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) |
1961 | { |
1962 | nlmsg_trim(skb, mark: start); |
1963 | } |
1964 | |
1965 | /** |
1966 | * __nla_validate_nested - Validate a stream of nested attributes |
1967 | * @start: container attribute |
1968 | * @maxtype: maximum attribute type to be expected |
1969 | * @policy: validation policy |
1970 | * @validate: validation strictness |
1971 | * @extack: extended ACK report struct |
1972 | * |
1973 | * Validates all attributes in the nested attribute stream against the |
1974 | * specified policy. Attributes with a type exceeding maxtype will be |
1975 | * ignored. See documenation of struct nla_policy for more details. |
1976 | * |
1977 | * Returns 0 on success or a negative error code. |
1978 | */ |
1979 | static inline int __nla_validate_nested(const struct nlattr *start, int maxtype, |
1980 | const struct nla_policy *policy, |
1981 | unsigned int validate, |
1982 | struct netlink_ext_ack *extack) |
1983 | { |
1984 | return __nla_validate(head: nla_data(nla: start), len: nla_len(nla: start), maxtype, policy, |
1985 | validate, extack); |
1986 | } |
1987 | |
1988 | static inline int |
1989 | nla_validate_nested(const struct nlattr *start, int maxtype, |
1990 | const struct nla_policy *policy, |
1991 | struct netlink_ext_ack *extack) |
1992 | { |
1993 | return __nla_validate_nested(start, maxtype, policy, |
1994 | NL_VALIDATE_STRICT, extack); |
1995 | } |
1996 | |
1997 | static inline int |
1998 | nla_validate_nested_deprecated(const struct nlattr *start, int maxtype, |
1999 | const struct nla_policy *policy, |
2000 | struct netlink_ext_ack *extack) |
2001 | { |
2002 | return __nla_validate_nested(start, maxtype, policy, |
2003 | validate: NL_VALIDATE_LIBERAL, extack); |
2004 | } |
2005 | |
2006 | /** |
2007 | * nla_need_padding_for_64bit - test 64-bit alignment of the next attribute |
2008 | * @skb: socket buffer the message is stored in |
2009 | * |
2010 | * Return true if padding is needed to align the next attribute (nla_data()) to |
2011 | * a 64-bit aligned area. |
2012 | */ |
2013 | static inline bool nla_need_padding_for_64bit(struct sk_buff *skb) |
2014 | { |
2015 | #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS |
2016 | /* The nlattr header is 4 bytes in size, that's why we test |
2017 | * if the skb->data _is_ aligned. A NOP attribute, plus |
2018 | * nlattr header for next attribute, will make nla_data() |
2019 | * 8-byte aligned. |
2020 | */ |
2021 | if (IS_ALIGNED((unsigned long)skb_tail_pointer(skb), 8)) |
2022 | return true; |
2023 | #endif |
2024 | return false; |
2025 | } |
2026 | |
2027 | /** |
2028 | * nla_align_64bit - 64-bit align the nla_data() of next attribute |
2029 | * @skb: socket buffer the message is stored in |
2030 | * @padattr: attribute type for the padding |
2031 | * |
2032 | * Conditionally emit a padding netlink attribute in order to make |
2033 | * the next attribute we emit have a 64-bit aligned nla_data() area. |
2034 | * This will only be done in architectures which do not have |
2035 | * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS defined. |
2036 | * |
2037 | * Returns zero on success or a negative error code. |
2038 | */ |
2039 | static inline int nla_align_64bit(struct sk_buff *skb, int padattr) |
2040 | { |
2041 | if (nla_need_padding_for_64bit(skb) && |
2042 | !nla_reserve(skb, attrtype: padattr, attrlen: 0)) |
2043 | return -EMSGSIZE; |
2044 | |
2045 | return 0; |
2046 | } |
2047 | |
2048 | /** |
2049 | * nla_total_size_64bit - total length of attribute including padding |
2050 | * @payload: length of payload |
2051 | */ |
2052 | static inline int nla_total_size_64bit(int payload) |
2053 | { |
2054 | return NLA_ALIGN(nla_attr_size(payload)) |
2055 | #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS |
2056 | + NLA_ALIGN(nla_attr_size(0)) |
2057 | #endif |
2058 | ; |
2059 | } |
2060 | |
2061 | /** |
2062 | * nla_for_each_attr - iterate over a stream of attributes |
2063 | * @pos: loop counter, set to current attribute |
2064 | * @head: head of attribute stream |
2065 | * @len: length of attribute stream |
2066 | * @rem: initialized to len, holds bytes currently remaining in stream |
2067 | */ |
2068 | #define nla_for_each_attr(pos, head, len, rem) \ |
2069 | for (pos = head, rem = len; \ |
2070 | nla_ok(pos, rem); \ |
2071 | pos = nla_next(pos, &(rem))) |
2072 | |
2073 | /** |
2074 | * nla_for_each_nested - iterate over nested attributes |
2075 | * @pos: loop counter, set to current attribute |
2076 | * @nla: attribute containing the nested attributes |
2077 | * @rem: initialized to len, holds bytes currently remaining in stream |
2078 | */ |
2079 | #define nla_for_each_nested(pos, nla, rem) \ |
2080 | nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem) |
2081 | |
2082 | /** |
2083 | * nla_is_last - Test if attribute is last in stream |
2084 | * @nla: attribute to test |
2085 | * @rem: bytes remaining in stream |
2086 | */ |
2087 | static inline bool nla_is_last(const struct nlattr *nla, int rem) |
2088 | { |
2089 | return nla->nla_len == rem; |
2090 | } |
2091 | |
2092 | void nla_get_range_unsigned(const struct nla_policy *pt, |
2093 | struct netlink_range_validation *range); |
2094 | void nla_get_range_signed(const struct nla_policy *pt, |
2095 | struct netlink_range_validation_signed *range); |
2096 | |
2097 | struct netlink_policy_dump_state; |
2098 | |
2099 | int netlink_policy_dump_add_policy(struct netlink_policy_dump_state **pstate, |
2100 | const struct nla_policy *policy, |
2101 | unsigned int maxtype); |
2102 | int netlink_policy_dump_get_policy_idx(struct netlink_policy_dump_state *state, |
2103 | const struct nla_policy *policy, |
2104 | unsigned int maxtype); |
2105 | bool netlink_policy_dump_loop(struct netlink_policy_dump_state *state); |
2106 | int netlink_policy_dump_write(struct sk_buff *skb, |
2107 | struct netlink_policy_dump_state *state); |
2108 | int netlink_policy_dump_attr_size_estimate(const struct nla_policy *pt); |
2109 | int netlink_policy_dump_write_attr(struct sk_buff *skb, |
2110 | const struct nla_policy *pt, |
2111 | int nestattr); |
2112 | void netlink_policy_dump_free(struct netlink_policy_dump_state *state); |
2113 | |
2114 | #endif |
2115 | |