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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
bfa83a9e TG |
2 | /* |
3 | * NETLINK Netlink attributes | |
4 | * | |
5 | * Authors: Thomas Graf <tgraf@suug.ch> | |
6 | * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> | |
7 | */ | |
8 | ||
8bc3bcc9 | 9 | #include <linux/export.h> |
bfa83a9e TG |
10 | #include <linux/kernel.h> |
11 | #include <linux/errno.h> | |
12 | #include <linux/jiffies.h> | |
bfa83a9e TG |
13 | #include <linux/skbuff.h> |
14 | #include <linux/string.h> | |
15 | #include <linux/types.h> | |
16 | #include <net/netlink.h> | |
17 | ||
6e237d09 DA |
18 | /* For these data types, attribute length should be exactly the given |
19 | * size. However, to maintain compatibility with broken commands, if the | |
20 | * attribute length does not match the expected size a warning is emitted | |
21 | * to the user that the command is sending invalid data and needs to be fixed. | |
22 | */ | |
28033ae4 | 23 | static const u8 nla_attr_len[NLA_TYPE_MAX+1] = { |
bfa83a9e TG |
24 | [NLA_U8] = sizeof(u8), |
25 | [NLA_U16] = sizeof(u16), | |
26 | [NLA_U32] = sizeof(u32), | |
27 | [NLA_U64] = sizeof(u64), | |
9eca2eb9 JA |
28 | [NLA_S8] = sizeof(s8), |
29 | [NLA_S16] = sizeof(s16), | |
30 | [NLA_S32] = sizeof(s32), | |
31 | [NLA_S64] = sizeof(s64), | |
bfa83a9e TG |
32 | }; |
33 | ||
28033ae4 | 34 | static const u8 nla_attr_minlen[NLA_TYPE_MAX+1] = { |
6e237d09 DA |
35 | [NLA_U8] = sizeof(u8), |
36 | [NLA_U16] = sizeof(u16), | |
37 | [NLA_U32] = sizeof(u32), | |
38 | [NLA_U64] = sizeof(u64), | |
28033ae4 DA |
39 | [NLA_MSECS] = sizeof(u64), |
40 | [NLA_NESTED] = NLA_HDRLEN, | |
6e237d09 DA |
41 | [NLA_S8] = sizeof(s8), |
42 | [NLA_S16] = sizeof(s16), | |
43 | [NLA_S32] = sizeof(s32), | |
44 | [NLA_S64] = sizeof(s64), | |
28033ae4 DA |
45 | }; |
46 | ||
64c83d83 | 47 | static int validate_nla_bitfield32(const struct nlattr *nla, |
48fde90a | 48 | const u32 *valid_flags_mask) |
64c83d83 JHS |
49 | { |
50 | const struct nla_bitfield32 *bf = nla_data(nla); | |
64c83d83 | 51 | |
48fde90a | 52 | if (!valid_flags_mask) |
64c83d83 JHS |
53 | return -EINVAL; |
54 | ||
55 | /*disallow invalid bit selector */ | |
56 | if (bf->selector & ~*valid_flags_mask) | |
57 | return -EINVAL; | |
58 | ||
59 | /*disallow invalid bit values */ | |
60 | if (bf->value & ~*valid_flags_mask) | |
61 | return -EINVAL; | |
62 | ||
63 | /*disallow valid bit values that are not selected*/ | |
64 | if (bf->value & ~bf->selector) | |
65 | return -EINVAL; | |
66 | ||
67 | return 0; | |
68 | } | |
69 | ||
1501d135 JB |
70 | static int nla_validate_array(const struct nlattr *head, int len, int maxtype, |
71 | const struct nla_policy *policy, | |
72 | struct netlink_ext_ack *extack) | |
73 | { | |
74 | const struct nlattr *entry; | |
75 | int rem; | |
76 | ||
77 | nla_for_each_attr(entry, head, len, rem) { | |
78 | int ret; | |
79 | ||
80 | if (nla_len(entry) == 0) | |
81 | continue; | |
82 | ||
83 | if (nla_len(entry) < NLA_HDRLEN) { | |
84 | NL_SET_ERR_MSG_ATTR(extack, entry, | |
85 | "Array element too short"); | |
86 | return -ERANGE; | |
87 | } | |
88 | ||
89 | ret = nla_validate(nla_data(entry), nla_len(entry), | |
90 | maxtype, policy, extack); | |
91 | if (ret < 0) | |
92 | return ret; | |
93 | } | |
94 | ||
95 | return 0; | |
96 | } | |
97 | ||
3654654f | 98 | static int validate_nla(const struct nlattr *nla, int maxtype, |
568b742a | 99 | const struct nla_policy *policy, |
c29f1845 | 100 | struct netlink_ext_ack *extack) |
bfa83a9e | 101 | { |
ef7c79ed | 102 | const struct nla_policy *pt; |
8f4c1f9b | 103 | int minlen = 0, attrlen = nla_len(nla), type = nla_type(nla); |
c29f1845 | 104 | int err = -ERANGE; |
bfa83a9e | 105 | |
8f4c1f9b | 106 | if (type <= 0 || type > maxtype) |
bfa83a9e TG |
107 | return 0; |
108 | ||
8f4c1f9b | 109 | pt = &policy[type]; |
bfa83a9e TG |
110 | |
111 | BUG_ON(pt->type > NLA_TYPE_MAX); | |
112 | ||
b60b87fc JB |
113 | if ((nla_attr_len[pt->type] && attrlen != nla_attr_len[pt->type]) || |
114 | (pt->type == NLA_EXACT_LEN_WARN && attrlen != pt->len)) { | |
6e237d09 DA |
115 | pr_warn_ratelimited("netlink: '%s': attribute type %d has an invalid length.\n", |
116 | current->comm, type); | |
28033ae4 DA |
117 | } |
118 | ||
a5531a5d | 119 | switch (pt->type) { |
b60b87fc JB |
120 | case NLA_EXACT_LEN: |
121 | if (attrlen != pt->len) | |
c29f1845 | 122 | goto out_err; |
b60b87fc JB |
123 | break; |
124 | ||
568b742a | 125 | case NLA_REJECT: |
c29f1845 JB |
126 | if (extack && pt->validation_data) { |
127 | NL_SET_BAD_ATTR(extack, nla); | |
128 | extack->_msg = pt->validation_data; | |
129 | return -EINVAL; | |
130 | } | |
131 | err = -EINVAL; | |
132 | goto out_err; | |
568b742a | 133 | |
a5531a5d TG |
134 | case NLA_FLAG: |
135 | if (attrlen > 0) | |
c29f1845 | 136 | goto out_err; |
a5531a5d | 137 | break; |
bfa83a9e | 138 | |
64c83d83 JHS |
139 | case NLA_BITFIELD32: |
140 | if (attrlen != sizeof(struct nla_bitfield32)) | |
c29f1845 | 141 | goto out_err; |
64c83d83 | 142 | |
c29f1845 JB |
143 | err = validate_nla_bitfield32(nla, pt->validation_data); |
144 | if (err) | |
145 | goto out_err; | |
146 | break; | |
64c83d83 | 147 | |
a5531a5d TG |
148 | case NLA_NUL_STRING: |
149 | if (pt->len) | |
150 | minlen = min_t(int, attrlen, pt->len + 1); | |
151 | else | |
152 | minlen = attrlen; | |
bfa83a9e | 153 | |
c29f1845 JB |
154 | if (!minlen || memchr(nla_data(nla), '\0', minlen) == NULL) { |
155 | err = -EINVAL; | |
156 | goto out_err; | |
157 | } | |
a5531a5d TG |
158 | /* fall through */ |
159 | ||
160 | case NLA_STRING: | |
161 | if (attrlen < 1) | |
c29f1845 | 162 | goto out_err; |
a5531a5d TG |
163 | |
164 | if (pt->len) { | |
165 | char *buf = nla_data(nla); | |
166 | ||
167 | if (buf[attrlen - 1] == '\0') | |
168 | attrlen--; | |
169 | ||
170 | if (attrlen > pt->len) | |
c29f1845 | 171 | goto out_err; |
a5531a5d TG |
172 | } |
173 | break; | |
174 | ||
d30045a0 JB |
175 | case NLA_BINARY: |
176 | if (pt->len && attrlen > pt->len) | |
c29f1845 | 177 | goto out_err; |
d30045a0 JB |
178 | break; |
179 | ||
ea5693cc PM |
180 | case NLA_NESTED: |
181 | /* a nested attributes is allowed to be empty; if its not, | |
182 | * it must have a size of at least NLA_HDRLEN. | |
183 | */ | |
184 | if (attrlen == 0) | |
185 | break; | |
9a659a35 JB |
186 | if (attrlen < NLA_HDRLEN) |
187 | goto out_err; | |
188 | if (pt->validation_data) { | |
189 | err = nla_validate(nla_data(nla), nla_len(nla), pt->len, | |
190 | pt->validation_data, extack); | |
191 | if (err < 0) { | |
192 | /* | |
193 | * return directly to preserve the inner | |
194 | * error message/attribute pointer | |
195 | */ | |
196 | return err; | |
197 | } | |
198 | } | |
199 | break; | |
1501d135 JB |
200 | case NLA_NESTED_ARRAY: |
201 | /* a nested array attribute is allowed to be empty; if its not, | |
202 | * it must have a size of at least NLA_HDRLEN. | |
203 | */ | |
204 | if (attrlen == 0) | |
205 | break; | |
206 | if (attrlen < NLA_HDRLEN) | |
207 | goto out_err; | |
208 | if (pt->validation_data) { | |
209 | int err; | |
210 | ||
211 | err = nla_validate_array(nla_data(nla), nla_len(nla), | |
212 | pt->len, pt->validation_data, | |
213 | extack); | |
214 | if (err < 0) { | |
215 | /* | |
216 | * return directly to preserve the inner | |
217 | * error message/attribute pointer | |
218 | */ | |
219 | return err; | |
220 | } | |
221 | } | |
222 | break; | |
a5531a5d TG |
223 | default: |
224 | if (pt->len) | |
225 | minlen = pt->len; | |
226 | else if (pt->type != NLA_UNSPEC) | |
227 | minlen = nla_attr_minlen[pt->type]; | |
228 | ||
229 | if (attrlen < minlen) | |
c29f1845 | 230 | goto out_err; |
a5531a5d | 231 | } |
bfa83a9e TG |
232 | |
233 | return 0; | |
c29f1845 JB |
234 | out_err: |
235 | NL_SET_ERR_MSG_ATTR(extack, nla, "Attribute failed policy validation"); | |
236 | return err; | |
bfa83a9e TG |
237 | } |
238 | ||
239 | /** | |
240 | * nla_validate - Validate a stream of attributes | |
241 | * @head: head of attribute stream | |
242 | * @len: length of attribute stream | |
243 | * @maxtype: maximum attribute type to be expected | |
244 | * @policy: validation policy | |
fceb6435 | 245 | * @extack: extended ACK report struct |
bfa83a9e TG |
246 | * |
247 | * Validates all attributes in the specified attribute stream against the | |
248 | * specified policy. Attributes with a type exceeding maxtype will be | |
249 | * ignored. See documenation of struct nla_policy for more details. | |
250 | * | |
251 | * Returns 0 on success or a negative error code. | |
252 | */ | |
3654654f | 253 | int nla_validate(const struct nlattr *head, int len, int maxtype, |
fceb6435 JB |
254 | const struct nla_policy *policy, |
255 | struct netlink_ext_ack *extack) | |
bfa83a9e | 256 | { |
3654654f | 257 | const struct nlattr *nla; |
fceb6435 | 258 | int rem; |
bfa83a9e TG |
259 | |
260 | nla_for_each_attr(nla, head, len, rem) { | |
c29f1845 | 261 | int err = validate_nla(nla, maxtype, policy, extack); |
fceb6435 | 262 | |
c29f1845 | 263 | if (err < 0) |
fceb6435 | 264 | return err; |
bfa83a9e TG |
265 | } |
266 | ||
fceb6435 | 267 | return 0; |
bfa83a9e | 268 | } |
6d6a138f | 269 | EXPORT_SYMBOL(nla_validate); |
bfa83a9e | 270 | |
e487eb99 HE |
271 | /** |
272 | * nla_policy_len - Determin the max. length of a policy | |
273 | * @policy: policy to use | |
274 | * @n: number of policies | |
275 | * | |
276 | * Determines the max. length of the policy. It is currently used | |
277 | * to allocated Netlink buffers roughly the size of the actual | |
278 | * message. | |
279 | * | |
280 | * Returns 0 on success or a negative error code. | |
281 | */ | |
282 | int | |
283 | nla_policy_len(const struct nla_policy *p, int n) | |
284 | { | |
285 | int i, len = 0; | |
286 | ||
e3fa3aff | 287 | for (i = 0; i < n; i++, p++) { |
e487eb99 HE |
288 | if (p->len) |
289 | len += nla_total_size(p->len); | |
28033ae4 DA |
290 | else if (nla_attr_len[p->type]) |
291 | len += nla_total_size(nla_attr_len[p->type]); | |
e487eb99 HE |
292 | else if (nla_attr_minlen[p->type]) |
293 | len += nla_total_size(nla_attr_minlen[p->type]); | |
294 | } | |
295 | ||
296 | return len; | |
297 | } | |
6d6a138f | 298 | EXPORT_SYMBOL(nla_policy_len); |
e487eb99 | 299 | |
bfa83a9e TG |
300 | /** |
301 | * nla_parse - Parse a stream of attributes into a tb buffer | |
302 | * @tb: destination array with maxtype+1 elements | |
303 | * @maxtype: maximum attribute type to be expected | |
304 | * @head: head of attribute stream | |
305 | * @len: length of attribute stream | |
10b595af | 306 | * @policy: validation policy |
bfa83a9e TG |
307 | * |
308 | * Parses a stream of attributes and stores a pointer to each attribute in | |
b595076a | 309 | * the tb array accessible via the attribute type. Attributes with a type |
bfa83a9e TG |
310 | * exceeding maxtype will be silently ignored for backwards compatibility |
311 | * reasons. policy may be set to NULL if no validation is required. | |
312 | * | |
313 | * Returns 0 on success or a negative error code. | |
314 | */ | |
3654654f | 315 | int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, |
fceb6435 JB |
316 | int len, const struct nla_policy *policy, |
317 | struct netlink_ext_ack *extack) | |
bfa83a9e | 318 | { |
3654654f | 319 | const struct nlattr *nla; |
c29f1845 | 320 | int rem; |
bfa83a9e TG |
321 | |
322 | memset(tb, 0, sizeof(struct nlattr *) * (maxtype + 1)); | |
323 | ||
324 | nla_for_each_attr(nla, head, len, rem) { | |
8f4c1f9b | 325 | u16 type = nla_type(nla); |
bfa83a9e TG |
326 | |
327 | if (type > 0 && type <= maxtype) { | |
328 | if (policy) { | |
c29f1845 JB |
329 | int err = validate_nla(nla, maxtype, policy, |
330 | extack); | |
331 | ||
332 | if (err < 0) | |
333 | return err; | |
bfa83a9e TG |
334 | } |
335 | ||
3654654f | 336 | tb[type] = (struct nlattr *)nla; |
bfa83a9e TG |
337 | } |
338 | } | |
339 | ||
340 | if (unlikely(rem > 0)) | |
bfc5184b MS |
341 | pr_warn_ratelimited("netlink: %d bytes leftover after parsing attributes in process `%s'.\n", |
342 | rem, current->comm); | |
bfa83a9e | 343 | |
c29f1845 | 344 | return 0; |
bfa83a9e | 345 | } |
6d6a138f | 346 | EXPORT_SYMBOL(nla_parse); |
bfa83a9e TG |
347 | |
348 | /** | |
349 | * nla_find - Find a specific attribute in a stream of attributes | |
350 | * @head: head of attribute stream | |
351 | * @len: length of attribute stream | |
352 | * @attrtype: type of attribute to look for | |
353 | * | |
354 | * Returns the first attribute in the stream matching the specified type. | |
355 | */ | |
3654654f | 356 | struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype) |
bfa83a9e | 357 | { |
3654654f | 358 | const struct nlattr *nla; |
bfa83a9e TG |
359 | int rem; |
360 | ||
361 | nla_for_each_attr(nla, head, len, rem) | |
8f4c1f9b | 362 | if (nla_type(nla) == attrtype) |
3654654f | 363 | return (struct nlattr *)nla; |
bfa83a9e TG |
364 | |
365 | return NULL; | |
366 | } | |
6d6a138f | 367 | EXPORT_SYMBOL(nla_find); |
bfa83a9e TG |
368 | |
369 | /** | |
370 | * nla_strlcpy - Copy string attribute payload into a sized buffer | |
371 | * @dst: where to copy the string to | |
10b595af | 372 | * @nla: attribute to copy the string from |
bfa83a9e TG |
373 | * @dstsize: size of destination buffer |
374 | * | |
375 | * Copies at most dstsize - 1 bytes into the destination buffer. | |
376 | * The result is always a valid NUL-terminated string. Unlike | |
377 | * strlcpy the destination buffer is always padded out. | |
378 | * | |
379 | * Returns the length of the source buffer. | |
380 | */ | |
381 | size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize) | |
382 | { | |
383 | size_t srclen = nla_len(nla); | |
384 | char *src = nla_data(nla); | |
385 | ||
386 | if (srclen > 0 && src[srclen - 1] == '\0') | |
387 | srclen--; | |
388 | ||
389 | if (dstsize > 0) { | |
390 | size_t len = (srclen >= dstsize) ? dstsize - 1 : srclen; | |
391 | ||
392 | memset(dst, 0, dstsize); | |
393 | memcpy(dst, src, len); | |
394 | } | |
395 | ||
396 | return srclen; | |
397 | } | |
6d6a138f | 398 | EXPORT_SYMBOL(nla_strlcpy); |
bfa83a9e | 399 | |
2cf0c8b3 PS |
400 | /** |
401 | * nla_strdup - Copy string attribute payload into a newly allocated buffer | |
402 | * @nla: attribute to copy the string from | |
403 | * @flags: the type of memory to allocate (see kmalloc). | |
404 | * | |
405 | * Returns a pointer to the allocated buffer or NULL on error. | |
406 | */ | |
407 | char *nla_strdup(const struct nlattr *nla, gfp_t flags) | |
408 | { | |
409 | size_t srclen = nla_len(nla); | |
410 | char *src = nla_data(nla), *dst; | |
411 | ||
412 | if (srclen > 0 && src[srclen - 1] == '\0') | |
413 | srclen--; | |
414 | ||
415 | dst = kmalloc(srclen + 1, flags); | |
416 | if (dst != NULL) { | |
417 | memcpy(dst, src, srclen); | |
418 | dst[srclen] = '\0'; | |
419 | } | |
420 | return dst; | |
421 | } | |
422 | EXPORT_SYMBOL(nla_strdup); | |
423 | ||
bfa83a9e TG |
424 | /** |
425 | * nla_memcpy - Copy a netlink attribute into another memory area | |
426 | * @dest: where to copy to memcpy | |
427 | * @src: netlink attribute to copy from | |
428 | * @count: size of the destination area | |
429 | * | |
430 | * Note: The number of bytes copied is limited by the length of | |
431 | * attribute's payload. memcpy | |
432 | * | |
433 | * Returns the number of bytes copied. | |
434 | */ | |
b057efd4 | 435 | int nla_memcpy(void *dest, const struct nlattr *src, int count) |
bfa83a9e TG |
436 | { |
437 | int minlen = min_t(int, count, nla_len(src)); | |
438 | ||
439 | memcpy(dest, nla_data(src), minlen); | |
5899f047 JB |
440 | if (count > minlen) |
441 | memset(dest + minlen, 0, count - minlen); | |
bfa83a9e TG |
442 | |
443 | return minlen; | |
444 | } | |
6d6a138f | 445 | EXPORT_SYMBOL(nla_memcpy); |
bfa83a9e TG |
446 | |
447 | /** | |
448 | * nla_memcmp - Compare an attribute with sized memory area | |
449 | * @nla: netlink attribute | |
450 | * @data: memory area | |
451 | * @size: size of memory area | |
452 | */ | |
453 | int nla_memcmp(const struct nlattr *nla, const void *data, | |
454 | size_t size) | |
455 | { | |
456 | int d = nla_len(nla) - size; | |
457 | ||
458 | if (d == 0) | |
459 | d = memcmp(nla_data(nla), data, size); | |
460 | ||
461 | return d; | |
462 | } | |
6d6a138f | 463 | EXPORT_SYMBOL(nla_memcmp); |
bfa83a9e TG |
464 | |
465 | /** | |
466 | * nla_strcmp - Compare a string attribute against a string | |
467 | * @nla: netlink string attribute | |
468 | * @str: another string | |
469 | */ | |
470 | int nla_strcmp(const struct nlattr *nla, const char *str) | |
471 | { | |
8b7b9324 PN |
472 | int len = strlen(str); |
473 | char *buf = nla_data(nla); | |
474 | int attrlen = nla_len(nla); | |
475 | int d; | |
bfa83a9e | 476 | |
8b7b9324 PN |
477 | if (attrlen > 0 && buf[attrlen - 1] == '\0') |
478 | attrlen--; | |
479 | ||
480 | d = attrlen - len; | |
bfa83a9e TG |
481 | if (d == 0) |
482 | d = memcmp(nla_data(nla), str, len); | |
483 | ||
484 | return d; | |
485 | } | |
6d6a138f | 486 | EXPORT_SYMBOL(nla_strcmp); |
bfa83a9e | 487 | |
90800216 | 488 | #ifdef CONFIG_NET |
bfa83a9e TG |
489 | /** |
490 | * __nla_reserve - reserve room for attribute on the skb | |
491 | * @skb: socket buffer to reserve room on | |
492 | * @attrtype: attribute type | |
493 | * @attrlen: length of attribute payload | |
494 | * | |
495 | * Adds a netlink attribute header to a socket buffer and reserves | |
496 | * room for the payload but does not copy it. | |
497 | * | |
498 | * The caller is responsible to ensure that the skb provides enough | |
499 | * tailroom for the attribute header and payload. | |
500 | */ | |
501 | struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen) | |
502 | { | |
503 | struct nlattr *nla; | |
504 | ||
4df864c1 | 505 | nla = skb_put(skb, nla_total_size(attrlen)); |
bfa83a9e TG |
506 | nla->nla_type = attrtype; |
507 | nla->nla_len = nla_attr_size(attrlen); | |
508 | ||
509 | memset((unsigned char *) nla + nla->nla_len, 0, nla_padlen(attrlen)); | |
510 | ||
511 | return nla; | |
512 | } | |
90800216 | 513 | EXPORT_SYMBOL(__nla_reserve); |
bfa83a9e | 514 | |
089bf1a6 ND |
515 | /** |
516 | * __nla_reserve_64bit - reserve room for attribute on the skb and align it | |
517 | * @skb: socket buffer to reserve room on | |
518 | * @attrtype: attribute type | |
519 | * @attrlen: length of attribute payload | |
11a99573 | 520 | * @padattr: attribute type for the padding |
089bf1a6 ND |
521 | * |
522 | * Adds a netlink attribute header to a socket buffer and reserves | |
523 | * room for the payload but does not copy it. It also ensure that this | |
11a99573 | 524 | * attribute will have a 64-bit aligned nla_data() area. |
089bf1a6 ND |
525 | * |
526 | * The caller is responsible to ensure that the skb provides enough | |
527 | * tailroom for the attribute header and payload. | |
528 | */ | |
529 | struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype, | |
530 | int attrlen, int padattr) | |
531 | { | |
532 | if (nla_need_padding_for_64bit(skb)) | |
533 | nla_align_64bit(skb, padattr); | |
534 | ||
535 | return __nla_reserve(skb, attrtype, attrlen); | |
536 | } | |
537 | EXPORT_SYMBOL(__nla_reserve_64bit); | |
538 | ||
fe4944e5 TG |
539 | /** |
540 | * __nla_reserve_nohdr - reserve room for attribute without header | |
541 | * @skb: socket buffer to reserve room on | |
542 | * @attrlen: length of attribute payload | |
543 | * | |
544 | * Reserves room for attribute payload without a header. | |
545 | * | |
546 | * The caller is responsible to ensure that the skb provides enough | |
547 | * tailroom for the payload. | |
548 | */ | |
549 | void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen) | |
550 | { | |
b952f4df | 551 | return skb_put_zero(skb, NLA_ALIGN(attrlen)); |
fe4944e5 | 552 | } |
90800216 | 553 | EXPORT_SYMBOL(__nla_reserve_nohdr); |
fe4944e5 | 554 | |
bfa83a9e TG |
555 | /** |
556 | * nla_reserve - reserve room for attribute on the skb | |
557 | * @skb: socket buffer to reserve room on | |
558 | * @attrtype: attribute type | |
559 | * @attrlen: length of attribute payload | |
560 | * | |
561 | * Adds a netlink attribute header to a socket buffer and reserves | |
562 | * room for the payload but does not copy it. | |
563 | * | |
564 | * Returns NULL if the tailroom of the skb is insufficient to store | |
565 | * the attribute header and payload. | |
566 | */ | |
567 | struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen) | |
568 | { | |
569 | if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen))) | |
570 | return NULL; | |
571 | ||
572 | return __nla_reserve(skb, attrtype, attrlen); | |
573 | } | |
90800216 | 574 | EXPORT_SYMBOL(nla_reserve); |
bfa83a9e | 575 | |
089bf1a6 ND |
576 | /** |
577 | * nla_reserve_64bit - reserve room for attribute on the skb and align it | |
578 | * @skb: socket buffer to reserve room on | |
579 | * @attrtype: attribute type | |
580 | * @attrlen: length of attribute payload | |
11a99573 | 581 | * @padattr: attribute type for the padding |
089bf1a6 ND |
582 | * |
583 | * Adds a netlink attribute header to a socket buffer and reserves | |
584 | * room for the payload but does not copy it. It also ensure that this | |
11a99573 | 585 | * attribute will have a 64-bit aligned nla_data() area. |
089bf1a6 ND |
586 | * |
587 | * Returns NULL if the tailroom of the skb is insufficient to store | |
588 | * the attribute header and payload. | |
589 | */ | |
590 | struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype, int attrlen, | |
591 | int padattr) | |
592 | { | |
593 | size_t len; | |
594 | ||
595 | if (nla_need_padding_for_64bit(skb)) | |
596 | len = nla_total_size_64bit(attrlen); | |
597 | else | |
598 | len = nla_total_size(attrlen); | |
599 | if (unlikely(skb_tailroom(skb) < len)) | |
600 | return NULL; | |
601 | ||
602 | return __nla_reserve_64bit(skb, attrtype, attrlen, padattr); | |
603 | } | |
604 | EXPORT_SYMBOL(nla_reserve_64bit); | |
605 | ||
fe4944e5 | 606 | /** |
10b595af | 607 | * nla_reserve_nohdr - reserve room for attribute without header |
fe4944e5 | 608 | * @skb: socket buffer to reserve room on |
10b595af | 609 | * @attrlen: length of attribute payload |
fe4944e5 TG |
610 | * |
611 | * Reserves room for attribute payload without a header. | |
612 | * | |
613 | * Returns NULL if the tailroom of the skb is insufficient to store | |
614 | * the attribute payload. | |
615 | */ | |
616 | void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen) | |
617 | { | |
618 | if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen))) | |
619 | return NULL; | |
620 | ||
621 | return __nla_reserve_nohdr(skb, attrlen); | |
622 | } | |
90800216 | 623 | EXPORT_SYMBOL(nla_reserve_nohdr); |
fe4944e5 | 624 | |
bfa83a9e TG |
625 | /** |
626 | * __nla_put - Add a netlink attribute to a socket buffer | |
627 | * @skb: socket buffer to add attribute to | |
628 | * @attrtype: attribute type | |
629 | * @attrlen: length of attribute payload | |
630 | * @data: head of attribute payload | |
631 | * | |
632 | * The caller is responsible to ensure that the skb provides enough | |
633 | * tailroom for the attribute header and payload. | |
634 | */ | |
635 | void __nla_put(struct sk_buff *skb, int attrtype, int attrlen, | |
636 | const void *data) | |
637 | { | |
638 | struct nlattr *nla; | |
639 | ||
640 | nla = __nla_reserve(skb, attrtype, attrlen); | |
641 | memcpy(nla_data(nla), data, attrlen); | |
642 | } | |
90800216 | 643 | EXPORT_SYMBOL(__nla_put); |
bfa83a9e | 644 | |
089bf1a6 ND |
645 | /** |
646 | * __nla_put_64bit - Add a netlink attribute to a socket buffer and align it | |
647 | * @skb: socket buffer to add attribute to | |
648 | * @attrtype: attribute type | |
649 | * @attrlen: length of attribute payload | |
650 | * @data: head of attribute payload | |
11a99573 | 651 | * @padattr: attribute type for the padding |
089bf1a6 ND |
652 | * |
653 | * The caller is responsible to ensure that the skb provides enough | |
654 | * tailroom for the attribute header and payload. | |
655 | */ | |
656 | void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen, | |
657 | const void *data, int padattr) | |
658 | { | |
659 | struct nlattr *nla; | |
660 | ||
661 | nla = __nla_reserve_64bit(skb, attrtype, attrlen, padattr); | |
662 | memcpy(nla_data(nla), data, attrlen); | |
663 | } | |
664 | EXPORT_SYMBOL(__nla_put_64bit); | |
665 | ||
fe4944e5 TG |
666 | /** |
667 | * __nla_put_nohdr - Add a netlink attribute without header | |
668 | * @skb: socket buffer to add attribute to | |
669 | * @attrlen: length of attribute payload | |
670 | * @data: head of attribute payload | |
671 | * | |
672 | * The caller is responsible to ensure that the skb provides enough | |
673 | * tailroom for the attribute payload. | |
674 | */ | |
675 | void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data) | |
676 | { | |
677 | void *start; | |
678 | ||
679 | start = __nla_reserve_nohdr(skb, attrlen); | |
680 | memcpy(start, data, attrlen); | |
681 | } | |
90800216 | 682 | EXPORT_SYMBOL(__nla_put_nohdr); |
bfa83a9e TG |
683 | |
684 | /** | |
685 | * nla_put - Add a netlink attribute to a socket buffer | |
686 | * @skb: socket buffer to add attribute to | |
687 | * @attrtype: attribute type | |
688 | * @attrlen: length of attribute payload | |
689 | * @data: head of attribute payload | |
690 | * | |
bc3ed28c | 691 | * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store |
bfa83a9e TG |
692 | * the attribute header and payload. |
693 | */ | |
694 | int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data) | |
695 | { | |
696 | if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen))) | |
bc3ed28c | 697 | return -EMSGSIZE; |
bfa83a9e TG |
698 | |
699 | __nla_put(skb, attrtype, attrlen, data); | |
700 | return 0; | |
701 | } | |
90800216 | 702 | EXPORT_SYMBOL(nla_put); |
bfa83a9e | 703 | |
089bf1a6 ND |
704 | /** |
705 | * nla_put_64bit - Add a netlink attribute to a socket buffer and align it | |
706 | * @skb: socket buffer to add attribute to | |
707 | * @attrtype: attribute type | |
708 | * @attrlen: length of attribute payload | |
709 | * @data: head of attribute payload | |
11a99573 | 710 | * @padattr: attribute type for the padding |
089bf1a6 ND |
711 | * |
712 | * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store | |
713 | * the attribute header and payload. | |
714 | */ | |
715 | int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen, | |
716 | const void *data, int padattr) | |
717 | { | |
718 | size_t len; | |
719 | ||
720 | if (nla_need_padding_for_64bit(skb)) | |
721 | len = nla_total_size_64bit(attrlen); | |
722 | else | |
723 | len = nla_total_size(attrlen); | |
724 | if (unlikely(skb_tailroom(skb) < len)) | |
725 | return -EMSGSIZE; | |
726 | ||
727 | __nla_put_64bit(skb, attrtype, attrlen, data, padattr); | |
728 | return 0; | |
729 | } | |
730 | EXPORT_SYMBOL(nla_put_64bit); | |
731 | ||
fe4944e5 TG |
732 | /** |
733 | * nla_put_nohdr - Add a netlink attribute without header | |
734 | * @skb: socket buffer to add attribute to | |
735 | * @attrlen: length of attribute payload | |
736 | * @data: head of attribute payload | |
737 | * | |
bc3ed28c | 738 | * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store |
fe4944e5 TG |
739 | * the attribute payload. |
740 | */ | |
741 | int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data) | |
742 | { | |
743 | if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen))) | |
bc3ed28c | 744 | return -EMSGSIZE; |
fe4944e5 TG |
745 | |
746 | __nla_put_nohdr(skb, attrlen, data); | |
747 | return 0; | |
748 | } | |
90800216 | 749 | EXPORT_SYMBOL(nla_put_nohdr); |
bfa83a9e | 750 | |
01480e1c PM |
751 | /** |
752 | * nla_append - Add a netlink attribute without header or padding | |
753 | * @skb: socket buffer to add attribute to | |
754 | * @attrlen: length of attribute payload | |
755 | * @data: head of attribute payload | |
756 | * | |
bc3ed28c | 757 | * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store |
01480e1c PM |
758 | * the attribute payload. |
759 | */ | |
760 | int nla_append(struct sk_buff *skb, int attrlen, const void *data) | |
761 | { | |
762 | if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen))) | |
bc3ed28c | 763 | return -EMSGSIZE; |
01480e1c | 764 | |
59ae1d12 | 765 | skb_put_data(skb, data, attrlen); |
01480e1c PM |
766 | return 0; |
767 | } | |
90800216 HX |
768 | EXPORT_SYMBOL(nla_append); |
769 | #endif |