blob: 489e15bde5c1d248ba4914da2aa4839f1084f5b7 [file] [log] [blame]
Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001// SPDX-License-Identifier: GPL-2.0
Thomas Grafbfa83a92005-11-10 02:25:51 +01002/*
3 * NETLINK Netlink attributes
4 *
5 * Authors: Thomas Graf <tgraf@suug.ch>
6 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
7 */
8
Paul Gortmaker8bc3bcc2011-11-16 21:29:17 -05009#include <linux/export.h>
Thomas Grafbfa83a92005-11-10 02:25:51 +010010#include <linux/kernel.h>
11#include <linux/errno.h>
12#include <linux/jiffies.h>
Eric Dumazetf09504022023-01-19 11:01:50 +000013#include <linux/nospec.h>
Thomas Grafbfa83a92005-11-10 02:25:51 +010014#include <linux/skbuff.h>
15#include <linux/string.h>
16#include <linux/types.h>
17#include <net/netlink.h>
18
David Ahern6e237d02017-12-06 20:09:12 -080019/* For these data types, attribute length should be exactly the given
20 * size. However, to maintain compatibility with broken commands, if the
21 * attribute length does not match the expected size a warning is emitted
22 * to the user that the command is sending invalid data and needs to be fixed.
23 */
David Ahern28033ae2017-11-07 21:59:40 -080024static const u8 nla_attr_len[NLA_TYPE_MAX+1] = {
Thomas Grafbfa83a92005-11-10 02:25:51 +010025 [NLA_U8] = sizeof(u8),
26 [NLA_U16] = sizeof(u16),
27 [NLA_U32] = sizeof(u32),
28 [NLA_U64] = sizeof(u64),
Julian Anastasov9eca2eb2012-08-25 22:47:57 +000029 [NLA_S8] = sizeof(s8),
30 [NLA_S16] = sizeof(s16),
31 [NLA_S32] = sizeof(s32),
32 [NLA_S64] = sizeof(s64),
Thomas Grafbfa83a92005-11-10 02:25:51 +010033};
34
David Ahern28033ae2017-11-07 21:59:40 -080035static const u8 nla_attr_minlen[NLA_TYPE_MAX+1] = {
David Ahern6e237d02017-12-06 20:09:12 -080036 [NLA_U8] = sizeof(u8),
37 [NLA_U16] = sizeof(u16),
38 [NLA_U32] = sizeof(u32),
39 [NLA_U64] = sizeof(u64),
David Ahern28033ae2017-11-07 21:59:40 -080040 [NLA_MSECS] = sizeof(u64),
41 [NLA_NESTED] = NLA_HDRLEN,
David Ahern6e237d02017-12-06 20:09:12 -080042 [NLA_S8] = sizeof(s8),
43 [NLA_S16] = sizeof(s16),
44 [NLA_S32] = sizeof(s32),
45 [NLA_S64] = sizeof(s64),
David Ahern28033ae2017-11-07 21:59:40 -080046};
47
Johannes Berg7690aa12020-04-30 22:13:06 +020048/*
49 * Nested policies might refer back to the original
50 * policy in some cases, and userspace could try to
51 * abuse that and recurse by nesting in the right
52 * ways. Limit recursion to avoid this problem.
53 */
54#define MAX_POLICY_RECURSION_DEPTH 10
55
56static int __nla_validate_parse(const struct nlattr *head, int len, int maxtype,
57 const struct nla_policy *policy,
58 unsigned int validate,
59 struct netlink_ext_ack *extack,
60 struct nlattr **tb, unsigned int depth);
61
Jamal Hadi Salim64c83d82017-07-30 13:24:49 -040062static int validate_nla_bitfield32(const struct nlattr *nla,
Johannes Berg47a14942020-04-30 22:13:05 +020063 const u32 valid_flags_mask)
Jamal Hadi Salim64c83d82017-07-30 13:24:49 -040064{
65 const struct nla_bitfield32 *bf = nla_data(nla);
Jamal Hadi Salim64c83d82017-07-30 13:24:49 -040066
Johannes Berg48fde902018-09-26 11:15:31 +020067 if (!valid_flags_mask)
Jamal Hadi Salim64c83d82017-07-30 13:24:49 -040068 return -EINVAL;
69
70 /*disallow invalid bit selector */
Johannes Berg47a14942020-04-30 22:13:05 +020071 if (bf->selector & ~valid_flags_mask)
Jamal Hadi Salim64c83d82017-07-30 13:24:49 -040072 return -EINVAL;
73
74 /*disallow invalid bit values */
Johannes Berg47a14942020-04-30 22:13:05 +020075 if (bf->value & ~valid_flags_mask)
Jamal Hadi Salim64c83d82017-07-30 13:24:49 -040076 return -EINVAL;
77
78 /*disallow valid bit values that are not selected*/
79 if (bf->value & ~bf->selector)
80 return -EINVAL;
81
82 return 0;
83}
84
Johannes Berg1501d132018-09-26 11:15:34 +020085static int nla_validate_array(const struct nlattr *head, int len, int maxtype,
86 const struct nla_policy *policy,
Johannes Berg8cb08172019-04-26 14:07:28 +020087 struct netlink_ext_ack *extack,
Johannes Berg7690aa12020-04-30 22:13:06 +020088 unsigned int validate, unsigned int depth)
Johannes Berg1501d132018-09-26 11:15:34 +020089{
90 const struct nlattr *entry;
91 int rem;
92
93 nla_for_each_attr(entry, head, len, rem) {
94 int ret;
95
96 if (nla_len(entry) == 0)
97 continue;
98
99 if (nla_len(entry) < NLA_HDRLEN) {
Johannes Berg44f36252020-10-08 12:45:17 +0200100 NL_SET_ERR_MSG_ATTR_POL(extack, entry, policy,
101 "Array element too short");
Johannes Berg1501d132018-09-26 11:15:34 +0200102 return -ERANGE;
103 }
104
Johannes Berg7690aa12020-04-30 22:13:06 +0200105 ret = __nla_validate_parse(nla_data(entry), nla_len(entry),
106 maxtype, policy, validate, extack,
107 NULL, depth + 1);
Johannes Berg1501d132018-09-26 11:15:34 +0200108 if (ret < 0)
109 return ret;
110 }
111
112 return 0;
113}
114
Johannes Berg2c28ae42020-04-30 22:13:11 +0200115void nla_get_range_unsigned(const struct nla_policy *pt,
116 struct netlink_range_validation *range)
Johannes Berg3e48be02018-09-27 11:28:35 +0200117{
Johannes Bergd06a09b2020-04-30 22:13:08 +0200118 WARN_ON_ONCE(pt->validation_type != NLA_VALIDATE_RANGE_PTR &&
119 (pt->min < 0 || pt->max < 0));
120
Johannes Berg2c28ae42020-04-30 22:13:11 +0200121 range->min = 0;
122
123 switch (pt->type) {
124 case NLA_U8:
125 range->max = U8_MAX;
126 break;
127 case NLA_U16:
Florian Westphalecaf75f2022-10-31 13:34:07 +0100128 case NLA_BE16:
Johannes Berg8aa26c52020-08-18 10:17:33 +0200129 case NLA_BINARY:
Johannes Berg2c28ae42020-04-30 22:13:11 +0200130 range->max = U16_MAX;
131 break;
132 case NLA_U32:
Florian Westphalecaf75f2022-10-31 13:34:07 +0100133 case NLA_BE32:
Johannes Berg2c28ae42020-04-30 22:13:11 +0200134 range->max = U32_MAX;
135 break;
136 case NLA_U64:
137 case NLA_MSECS:
138 range->max = U64_MAX;
139 break;
140 default:
141 WARN_ON_ONCE(1);
142 return;
143 }
144
Johannes Bergd06a09b2020-04-30 22:13:08 +0200145 switch (pt->validation_type) {
146 case NLA_VALIDATE_RANGE:
Johannes Berg8aa26c52020-08-18 10:17:33 +0200147 case NLA_VALIDATE_RANGE_WARN_TOO_LONG:
Johannes Bergd06a09b2020-04-30 22:13:08 +0200148 range->min = pt->min;
149 range->max = pt->max;
150 break;
151 case NLA_VALIDATE_RANGE_PTR:
Johannes Berg2c28ae42020-04-30 22:13:11 +0200152 *range = *pt->range;
Johannes Bergd06a09b2020-04-30 22:13:08 +0200153 break;
154 case NLA_VALIDATE_MIN:
155 range->min = pt->min;
156 break;
157 case NLA_VALIDATE_MAX:
158 range->max = pt->max;
159 break;
Johannes Berg2c28ae42020-04-30 22:13:11 +0200160 default:
161 break;
Johannes Bergd06a09b2020-04-30 22:13:08 +0200162 }
Johannes Berg2c28ae42020-04-30 22:13:11 +0200163}
164
Johannes Berg8aa26c52020-08-18 10:17:33 +0200165static int nla_validate_range_unsigned(const struct nla_policy *pt,
166 const struct nlattr *nla,
167 struct netlink_ext_ack *extack,
168 unsigned int validate)
Johannes Berg2c28ae42020-04-30 22:13:11 +0200169{
170 struct netlink_range_validation range;
171 u64 value;
Johannes Berg3e48be02018-09-27 11:28:35 +0200172
173 switch (pt->type) {
174 case NLA_U8:
175 value = nla_get_u8(nla);
176 break;
177 case NLA_U16:
Florian Westphalecaf75f2022-10-31 13:34:07 +0100178 value = nla_get_u16(nla);
179 break;
Johannes Berg3e48be02018-09-27 11:28:35 +0200180 case NLA_U32:
Florian Westphalecaf75f2022-10-31 13:34:07 +0100181 value = nla_get_u32(nla);
182 break;
Johannes Bergd06a09b2020-04-30 22:13:08 +0200183 case NLA_U64:
Florian Westphalecaf75f2022-10-31 13:34:07 +0100184 value = nla_get_u64(nla);
Florian Westphal08724ef2022-09-05 12:09:36 +0200185 break;
Johannes Bergda4063b2020-04-30 22:13:09 +0200186 case NLA_MSECS:
Johannes Bergd06a09b2020-04-30 22:13:08 +0200187 value = nla_get_u64(nla);
188 break;
Johannes Berg8aa26c52020-08-18 10:17:33 +0200189 case NLA_BINARY:
190 value = nla_len(nla);
191 break;
Florian Westphalecaf75f2022-10-31 13:34:07 +0100192 case NLA_BE16:
193 value = ntohs(nla_get_be16(nla));
194 break;
195 case NLA_BE32:
196 value = ntohl(nla_get_be32(nla));
197 break;
Johannes Bergd06a09b2020-04-30 22:13:08 +0200198 default:
199 return -EINVAL;
200 }
201
Johannes Berg2c28ae42020-04-30 22:13:11 +0200202 nla_get_range_unsigned(pt, &range);
203
Johannes Berg8aa26c52020-08-18 10:17:33 +0200204 if (pt->validation_type == NLA_VALIDATE_RANGE_WARN_TOO_LONG &&
205 pt->type == NLA_BINARY && value > range.max) {
206 pr_warn_ratelimited("netlink: '%s': attribute type %d has an invalid length.\n",
207 current->comm, pt->type);
208 if (validate & NL_VALIDATE_STRICT_ATTRS) {
Johannes Berg44f36252020-10-08 12:45:17 +0200209 NL_SET_ERR_MSG_ATTR_POL(extack, nla, pt,
210 "invalid attribute length");
Johannes Berg8aa26c52020-08-18 10:17:33 +0200211 return -EINVAL;
212 }
213
214 /* this assumes min <= max (don't validate against min) */
215 return 0;
216 }
217
Johannes Berg2c28ae42020-04-30 22:13:11 +0200218 if (value < range.min || value > range.max) {
Johannes Berg8aa26c52020-08-18 10:17:33 +0200219 bool binary = pt->type == NLA_BINARY;
220
221 if (binary)
Johannes Berg44f36252020-10-08 12:45:17 +0200222 NL_SET_ERR_MSG_ATTR_POL(extack, nla, pt,
223 "binary attribute size out of range");
Johannes Berg8aa26c52020-08-18 10:17:33 +0200224 else
Johannes Berg44f36252020-10-08 12:45:17 +0200225 NL_SET_ERR_MSG_ATTR_POL(extack, nla, pt,
226 "integer out of range");
Johannes Berg8aa26c52020-08-18 10:17:33 +0200227
Johannes Bergd06a09b2020-04-30 22:13:08 +0200228 return -ERANGE;
229 }
230
231 return 0;
232}
233
Johannes Berg2c28ae42020-04-30 22:13:11 +0200234void nla_get_range_signed(const struct nla_policy *pt,
235 struct netlink_range_validation_signed *range)
Johannes Bergd06a09b2020-04-30 22:13:08 +0200236{
Johannes Berg2c28ae42020-04-30 22:13:11 +0200237 switch (pt->type) {
238 case NLA_S8:
239 range->min = S8_MIN;
240 range->max = S8_MAX;
241 break;
242 case NLA_S16:
243 range->min = S16_MIN;
244 range->max = S16_MAX;
245 break;
246 case NLA_S32:
247 range->min = S32_MIN;
248 range->max = S32_MAX;
249 break;
250 case NLA_S64:
251 range->min = S64_MIN;
252 range->max = S64_MAX;
253 break;
254 default:
255 WARN_ON_ONCE(1);
256 return;
257 }
Johannes Bergd06a09b2020-04-30 22:13:08 +0200258
259 switch (pt->validation_type) {
260 case NLA_VALIDATE_RANGE:
261 range->min = pt->min;
262 range->max = pt->max;
263 break;
264 case NLA_VALIDATE_RANGE_PTR:
Johannes Berg2c28ae42020-04-30 22:13:11 +0200265 *range = *pt->range_signed;
Johannes Bergd06a09b2020-04-30 22:13:08 +0200266 break;
267 case NLA_VALIDATE_MIN:
268 range->min = pt->min;
269 break;
270 case NLA_VALIDATE_MAX:
271 range->max = pt->max;
272 break;
Johannes Berg2c28ae42020-04-30 22:13:11 +0200273 default:
274 break;
Johannes Bergd06a09b2020-04-30 22:13:08 +0200275 }
Johannes Berg2c28ae42020-04-30 22:13:11 +0200276}
277
278static int nla_validate_int_range_signed(const struct nla_policy *pt,
279 const struct nlattr *nla,
280 struct netlink_ext_ack *extack)
281{
282 struct netlink_range_validation_signed range;
283 s64 value;
Johannes Bergd06a09b2020-04-30 22:13:08 +0200284
285 switch (pt->type) {
Johannes Berg3e48be02018-09-27 11:28:35 +0200286 case NLA_S8:
287 value = nla_get_s8(nla);
288 break;
289 case NLA_S16:
290 value = nla_get_s16(nla);
291 break;
292 case NLA_S32:
293 value = nla_get_s32(nla);
294 break;
295 case NLA_S64:
296 value = nla_get_s64(nla);
297 break;
Johannes Berg3e48be02018-09-27 11:28:35 +0200298 default:
Johannes Berg3e48be02018-09-27 11:28:35 +0200299 return -EINVAL;
300 }
301
Johannes Berg2c28ae42020-04-30 22:13:11 +0200302 nla_get_range_signed(pt, &range);
303
304 if (value < range.min || value > range.max) {
Johannes Berg44f36252020-10-08 12:45:17 +0200305 NL_SET_ERR_MSG_ATTR_POL(extack, nla, pt,
306 "integer out of range");
Johannes Berg3e48be02018-09-27 11:28:35 +0200307 return -ERANGE;
308 }
309
310 return 0;
311}
312
Johannes Bergd06a09b2020-04-30 22:13:08 +0200313static int nla_validate_int_range(const struct nla_policy *pt,
314 const struct nlattr *nla,
Johannes Berg8aa26c52020-08-18 10:17:33 +0200315 struct netlink_ext_ack *extack,
316 unsigned int validate)
Johannes Bergd06a09b2020-04-30 22:13:08 +0200317{
318 switch (pt->type) {
319 case NLA_U8:
320 case NLA_U16:
321 case NLA_U32:
322 case NLA_U64:
Johannes Bergda4063b2020-04-30 22:13:09 +0200323 case NLA_MSECS:
Johannes Berg8aa26c52020-08-18 10:17:33 +0200324 case NLA_BINARY:
Florian Westphalecaf75f2022-10-31 13:34:07 +0100325 case NLA_BE16:
326 case NLA_BE32:
Johannes Berg8aa26c52020-08-18 10:17:33 +0200327 return nla_validate_range_unsigned(pt, nla, extack, validate);
Johannes Bergd06a09b2020-04-30 22:13:08 +0200328 case NLA_S8:
329 case NLA_S16:
330 case NLA_S32:
331 case NLA_S64:
332 return nla_validate_int_range_signed(pt, nla, extack);
333 default:
334 WARN_ON(1);
335 return -EINVAL;
336 }
337}
338
Jakub Kicinskibdbb4e22020-10-05 15:07:38 -0700339static int nla_validate_mask(const struct nla_policy *pt,
340 const struct nlattr *nla,
341 struct netlink_ext_ack *extack)
342{
343 u64 value;
344
345 switch (pt->type) {
346 case NLA_U8:
347 value = nla_get_u8(nla);
348 break;
349 case NLA_U16:
350 value = nla_get_u16(nla);
351 break;
352 case NLA_U32:
353 value = nla_get_u32(nla);
354 break;
355 case NLA_U64:
356 value = nla_get_u64(nla);
357 break;
358 default:
359 return -EINVAL;
360 }
361
362 if (value & ~(u64)pt->mask) {
363 NL_SET_ERR_MSG_ATTR(extack, nla, "reserved bit set");
364 return -EINVAL;
365 }
366
367 return 0;
368}
369
Jan Engelhardt36546542010-11-16 09:52:32 -0800370static int validate_nla(const struct nlattr *nla, int maxtype,
Johannes Berg8cb08172019-04-26 14:07:28 +0200371 const struct nla_policy *policy, unsigned int validate,
Johannes Berg7690aa12020-04-30 22:13:06 +0200372 struct netlink_ext_ack *extack, unsigned int depth)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100373{
Johannes Berg56738f42019-04-26 14:07:30 +0200374 u16 strict_start_type = policy[0].strict_start_type;
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700375 const struct nla_policy *pt;
Thomas Graf8f4c1f92007-09-12 14:44:36 +0200376 int minlen = 0, attrlen = nla_len(nla), type = nla_type(nla);
Johannes Bergc29f1842018-09-26 11:15:32 +0200377 int err = -ERANGE;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100378
Johannes Berg56738f42019-04-26 14:07:30 +0200379 if (strict_start_type && type >= strict_start_type)
380 validate |= NL_VALIDATE_STRICT;
381
Thomas Graf8f4c1f92007-09-12 14:44:36 +0200382 if (type <= 0 || type > maxtype)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100383 return 0;
384
Eric Dumazetf09504022023-01-19 11:01:50 +0000385 type = array_index_nospec(type, maxtype + 1);
Thomas Graf8f4c1f92007-09-12 14:44:36 +0200386 pt = &policy[type];
Thomas Grafbfa83a92005-11-10 02:25:51 +0100387
388 BUG_ON(pt->type > NLA_TYPE_MAX);
389
Johannes Berg8aa26c52020-08-18 10:17:33 +0200390 if (nla_attr_len[pt->type] && attrlen != nla_attr_len[pt->type]) {
David Ahern6e237d02017-12-06 20:09:12 -0800391 pr_warn_ratelimited("netlink: '%s': attribute type %d has an invalid length.\n",
392 current->comm, type);
Johannes Berg8cb08172019-04-26 14:07:28 +0200393 if (validate & NL_VALIDATE_STRICT_ATTRS) {
Johannes Berg44f36252020-10-08 12:45:17 +0200394 NL_SET_ERR_MSG_ATTR_POL(extack, nla, pt,
395 "invalid attribute length");
Johannes Berg8cb08172019-04-26 14:07:28 +0200396 return -EINVAL;
397 }
David Ahern28033ae2017-11-07 21:59:40 -0800398 }
399
Michal Kubecekb424e432019-05-02 16:15:10 +0200400 if (validate & NL_VALIDATE_NESTED) {
401 if ((pt->type == NLA_NESTED || pt->type == NLA_NESTED_ARRAY) &&
402 !(nla->nla_type & NLA_F_NESTED)) {
Johannes Berg44f36252020-10-08 12:45:17 +0200403 NL_SET_ERR_MSG_ATTR_POL(extack, nla, pt,
404 "NLA_F_NESTED is missing");
Michal Kubecekb424e432019-05-02 16:15:10 +0200405 return -EINVAL;
406 }
407 if (pt->type != NLA_NESTED && pt->type != NLA_NESTED_ARRAY &&
408 pt->type != NLA_UNSPEC && (nla->nla_type & NLA_F_NESTED)) {
Johannes Berg44f36252020-10-08 12:45:17 +0200409 NL_SET_ERR_MSG_ATTR_POL(extack, nla, pt,
410 "NLA_F_NESTED not expected");
Michal Kubecekb424e432019-05-02 16:15:10 +0200411 return -EINVAL;
412 }
413 }
414
Thomas Grafa5531a52006-08-26 20:11:47 -0700415 switch (pt->type) {
Johannes Berg568b7422018-09-17 11:57:28 +0200416 case NLA_REJECT:
Johannes Berg47a14942020-04-30 22:13:05 +0200417 if (extack && pt->reject_message) {
Johannes Bergc29f1842018-09-26 11:15:32 +0200418 NL_SET_BAD_ATTR(extack, nla);
Johannes Berg47a14942020-04-30 22:13:05 +0200419 extack->_msg = pt->reject_message;
Johannes Bergc29f1842018-09-26 11:15:32 +0200420 return -EINVAL;
421 }
422 err = -EINVAL;
423 goto out_err;
Johannes Berg568b7422018-09-17 11:57:28 +0200424
Thomas Grafa5531a52006-08-26 20:11:47 -0700425 case NLA_FLAG:
426 if (attrlen > 0)
Johannes Bergc29f1842018-09-26 11:15:32 +0200427 goto out_err;
Thomas Grafa5531a52006-08-26 20:11:47 -0700428 break;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100429
Jamal Hadi Salim64c83d82017-07-30 13:24:49 -0400430 case NLA_BITFIELD32:
431 if (attrlen != sizeof(struct nla_bitfield32))
Johannes Bergc29f1842018-09-26 11:15:32 +0200432 goto out_err;
Jamal Hadi Salim64c83d82017-07-30 13:24:49 -0400433
Johannes Berg47a14942020-04-30 22:13:05 +0200434 err = validate_nla_bitfield32(nla, pt->bitfield32_valid);
Johannes Bergc29f1842018-09-26 11:15:32 +0200435 if (err)
436 goto out_err;
437 break;
Jamal Hadi Salim64c83d82017-07-30 13:24:49 -0400438
Thomas Grafa5531a52006-08-26 20:11:47 -0700439 case NLA_NUL_STRING:
440 if (pt->len)
441 minlen = min_t(int, attrlen, pt->len + 1);
442 else
443 minlen = attrlen;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100444
Johannes Bergc29f1842018-09-26 11:15:32 +0200445 if (!minlen || memchr(nla_data(nla), '\0', minlen) == NULL) {
446 err = -EINVAL;
447 goto out_err;
448 }
Gustavo A. R. Silva36f9ff92020-11-19 07:11:44 -0600449 fallthrough;
Thomas Grafa5531a52006-08-26 20:11:47 -0700450
451 case NLA_STRING:
452 if (attrlen < 1)
Johannes Bergc29f1842018-09-26 11:15:32 +0200453 goto out_err;
Thomas Grafa5531a52006-08-26 20:11:47 -0700454
455 if (pt->len) {
456 char *buf = nla_data(nla);
457
458 if (buf[attrlen - 1] == '\0')
459 attrlen--;
460
461 if (attrlen > pt->len)
Johannes Bergc29f1842018-09-26 11:15:32 +0200462 goto out_err;
Thomas Grafa5531a52006-08-26 20:11:47 -0700463 }
464 break;
465
Johannes Bergd30045a2007-03-23 11:37:48 -0700466 case NLA_BINARY:
467 if (pt->len && attrlen > pt->len)
Johannes Bergc29f1842018-09-26 11:15:32 +0200468 goto out_err;
Johannes Bergd30045a2007-03-23 11:37:48 -0700469 break;
470
Patrick McHardyea5693c2008-11-28 03:05:19 -0800471 case NLA_NESTED:
472 /* a nested attributes is allowed to be empty; if its not,
473 * it must have a size of at least NLA_HDRLEN.
474 */
475 if (attrlen == 0)
476 break;
Johannes Berg9a659a352018-09-26 11:15:33 +0200477 if (attrlen < NLA_HDRLEN)
478 goto out_err;
Johannes Berg47a14942020-04-30 22:13:05 +0200479 if (pt->nested_policy) {
Johannes Berg7690aa12020-04-30 22:13:06 +0200480 err = __nla_validate_parse(nla_data(nla), nla_len(nla),
481 pt->len, pt->nested_policy,
482 validate, extack, NULL,
483 depth + 1);
Johannes Berg9a659a352018-09-26 11:15:33 +0200484 if (err < 0) {
485 /*
486 * return directly to preserve the inner
487 * error message/attribute pointer
488 */
489 return err;
490 }
491 }
492 break;
Johannes Berg1501d132018-09-26 11:15:34 +0200493 case NLA_NESTED_ARRAY:
494 /* a nested array attribute is allowed to be empty; if its not,
495 * it must have a size of at least NLA_HDRLEN.
496 */
497 if (attrlen == 0)
498 break;
499 if (attrlen < NLA_HDRLEN)
500 goto out_err;
Johannes Berg47a14942020-04-30 22:13:05 +0200501 if (pt->nested_policy) {
Johannes Berg1501d132018-09-26 11:15:34 +0200502 int err;
503
504 err = nla_validate_array(nla_data(nla), nla_len(nla),
Johannes Berg47a14942020-04-30 22:13:05 +0200505 pt->len, pt->nested_policy,
Johannes Berg7690aa12020-04-30 22:13:06 +0200506 extack, validate, depth);
Johannes Berg1501d132018-09-26 11:15:34 +0200507 if (err < 0) {
508 /*
509 * return directly to preserve the inner
510 * error message/attribute pointer
511 */
512 return err;
513 }
514 }
515 break;
Johannes Berg6f455f52019-04-26 14:07:27 +0200516
517 case NLA_UNSPEC:
Johannes Berg8cb08172019-04-26 14:07:28 +0200518 if (validate & NL_VALIDATE_UNSPEC) {
519 NL_SET_ERR_MSG_ATTR(extack, nla,
520 "Unsupported attribute");
521 return -EINVAL;
522 }
Johannes Berg6f455f52019-04-26 14:07:27 +0200523 if (attrlen < pt->len)
524 goto out_err;
525 break;
526
Thomas Grafa5531a52006-08-26 20:11:47 -0700527 default:
528 if (pt->len)
529 minlen = pt->len;
Johannes Berg6f455f52019-04-26 14:07:27 +0200530 else
Thomas Grafa5531a52006-08-26 20:11:47 -0700531 minlen = nla_attr_minlen[pt->type];
532
533 if (attrlen < minlen)
Johannes Bergc29f1842018-09-26 11:15:32 +0200534 goto out_err;
Thomas Grafa5531a52006-08-26 20:11:47 -0700535 }
Thomas Grafbfa83a92005-11-10 02:25:51 +0100536
Johannes Berg3e48be02018-09-27 11:28:35 +0200537 /* further validation */
538 switch (pt->validation_type) {
539 case NLA_VALIDATE_NONE:
540 /* nothing to do */
541 break;
Johannes Bergd06a09b2020-04-30 22:13:08 +0200542 case NLA_VALIDATE_RANGE_PTR:
Johannes Berg3e48be02018-09-27 11:28:35 +0200543 case NLA_VALIDATE_RANGE:
Johannes Berg8aa26c52020-08-18 10:17:33 +0200544 case NLA_VALIDATE_RANGE_WARN_TOO_LONG:
Johannes Berg3e48be02018-09-27 11:28:35 +0200545 case NLA_VALIDATE_MIN:
546 case NLA_VALIDATE_MAX:
Johannes Berg8aa26c52020-08-18 10:17:33 +0200547 err = nla_validate_int_range(pt, nla, extack, validate);
Johannes Berg3e48be02018-09-27 11:28:35 +0200548 if (err)
549 return err;
550 break;
Jakub Kicinskibdbb4e22020-10-05 15:07:38 -0700551 case NLA_VALIDATE_MASK:
552 err = nla_validate_mask(pt, nla, extack);
553 if (err)
554 return err;
555 break;
Johannes Berg33188bd2018-09-27 11:28:36 +0200556 case NLA_VALIDATE_FUNCTION:
557 if (pt->validate) {
558 err = pt->validate(nla, extack);
559 if (err)
560 return err;
561 }
562 break;
Johannes Berg3e48be02018-09-27 11:28:35 +0200563 }
564
Thomas Grafbfa83a92005-11-10 02:25:51 +0100565 return 0;
Johannes Bergc29f1842018-09-26 11:15:32 +0200566out_err:
Johannes Berg44f36252020-10-08 12:45:17 +0200567 NL_SET_ERR_MSG_ATTR_POL(extack, nla, pt,
568 "Attribute failed policy validation");
Johannes Bergc29f1842018-09-26 11:15:32 +0200569 return err;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100570}
571
Johannes Berg8cb08172019-04-26 14:07:28 +0200572static int __nla_validate_parse(const struct nlattr *head, int len, int maxtype,
573 const struct nla_policy *policy,
574 unsigned int validate,
575 struct netlink_ext_ack *extack,
Johannes Berg7690aa12020-04-30 22:13:06 +0200576 struct nlattr **tb, unsigned int depth)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100577{
Jan Engelhardt36546542010-11-16 09:52:32 -0800578 const struct nlattr *nla;
Johannes Bergfceb6432017-04-12 14:34:07 +0200579 int rem;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100580
Johannes Berg7690aa12020-04-30 22:13:06 +0200581 if (depth >= MAX_POLICY_RECURSION_DEPTH) {
582 NL_SET_ERR_MSG(extack,
583 "allowed policy recursion depth exceeded");
584 return -EINVAL;
585 }
586
Johannes Berg8cb08172019-04-26 14:07:28 +0200587 if (tb)
588 memset(tb, 0, sizeof(struct nlattr *) * (maxtype + 1));
Johannes Bergfceb6432017-04-12 14:34:07 +0200589
Johannes Berg8cb08172019-04-26 14:07:28 +0200590 nla_for_each_attr(nla, head, len, rem) {
591 u16 type = nla_type(nla);
592
593 if (type == 0 || type > maxtype) {
594 if (validate & NL_VALIDATE_MAXTYPE) {
Michal Kubecekd54a16b2019-05-02 16:15:10 +0200595 NL_SET_ERR_MSG_ATTR(extack, nla,
596 "Unknown attribute type");
Johannes Berg8cb08172019-04-26 14:07:28 +0200597 return -EINVAL;
598 }
599 continue;
600 }
Eric Dumazetf09504022023-01-19 11:01:50 +0000601 type = array_index_nospec(type, maxtype + 1);
Johannes Berg8cb08172019-04-26 14:07:28 +0200602 if (policy) {
603 int err = validate_nla(nla, maxtype, policy,
Johannes Berg7690aa12020-04-30 22:13:06 +0200604 validate, extack, depth);
Johannes Berg8cb08172019-04-26 14:07:28 +0200605
606 if (err < 0)
607 return err;
608 }
609
610 if (tb)
611 tb[type] = (struct nlattr *)nla;
612 }
613
614 if (unlikely(rem > 0)) {
615 pr_warn_ratelimited("netlink: %d bytes leftover after parsing attributes in process `%s'.\n",
616 rem, current->comm);
617 NL_SET_ERR_MSG(extack, "bytes leftover after parsing attributes");
618 if (validate & NL_VALIDATE_TRAILING)
619 return -EINVAL;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100620 }
621
Johannes Bergfceb6432017-04-12 14:34:07 +0200622 return 0;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100623}
Johannes Berg8cb08172019-04-26 14:07:28 +0200624
625/**
626 * __nla_validate - Validate a stream of attributes
627 * @head: head of attribute stream
628 * @len: length of attribute stream
629 * @maxtype: maximum attribute type to be expected
630 * @policy: validation policy
631 * @validate: validation strictness
632 * @extack: extended ACK report struct
633 *
634 * Validates all attributes in the specified attribute stream against the
635 * specified policy. Validation depends on the validate flags passed, see
636 * &enum netlink_validation for more details on that.
Zhen Lei9dbbc3b2021-07-07 18:07:31 -0700637 * See documentation of struct nla_policy for more details.
Johannes Berg8cb08172019-04-26 14:07:28 +0200638 *
639 * Returns 0 on success or a negative error code.
640 */
641int __nla_validate(const struct nlattr *head, int len, int maxtype,
642 const struct nla_policy *policy, unsigned int validate,
643 struct netlink_ext_ack *extack)
644{
645 return __nla_validate_parse(head, len, maxtype, policy, validate,
Johannes Berg7690aa12020-04-30 22:13:06 +0200646 extack, NULL, 0);
Johannes Berg8cb08172019-04-26 14:07:28 +0200647}
648EXPORT_SYMBOL(__nla_validate);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100649
650/**
Zhen Lei9dbbc3b2021-07-07 18:07:31 -0700651 * nla_policy_len - Determine the max. length of a policy
Yang Li8e18be72022-11-07 14:26:23 +0800652 * @p: policy to use
Holger Eitzenbergere487eb992009-03-25 18:26:30 +0100653 * @n: number of policies
654 *
655 * Determines the max. length of the policy. It is currently used
656 * to allocated Netlink buffers roughly the size of the actual
657 * message.
658 *
659 * Returns 0 on success or a negative error code.
660 */
661int
662nla_policy_len(const struct nla_policy *p, int n)
663{
664 int i, len = 0;
665
Lars Ellenberge3fa3af2011-02-28 12:38:25 -0800666 for (i = 0; i < n; i++, p++) {
Holger Eitzenbergere487eb992009-03-25 18:26:30 +0100667 if (p->len)
668 len += nla_total_size(p->len);
David Ahern28033ae2017-11-07 21:59:40 -0800669 else if (nla_attr_len[p->type])
670 len += nla_total_size(nla_attr_len[p->type]);
Holger Eitzenbergere487eb992009-03-25 18:26:30 +0100671 else if (nla_attr_minlen[p->type])
672 len += nla_total_size(nla_attr_minlen[p->type]);
673 }
674
675 return len;
676}
Fabian Frederick6d6a1382014-06-04 16:11:57 -0700677EXPORT_SYMBOL(nla_policy_len);
Holger Eitzenbergere487eb992009-03-25 18:26:30 +0100678
679/**
Johannes Berg8cb08172019-04-26 14:07:28 +0200680 * __nla_parse - Parse a stream of attributes into a tb buffer
Thomas Grafbfa83a92005-11-10 02:25:51 +0100681 * @tb: destination array with maxtype+1 elements
682 * @maxtype: maximum attribute type to be expected
683 * @head: head of attribute stream
684 * @len: length of attribute stream
Julius Volz10b595a2008-06-27 20:02:14 -0700685 * @policy: validation policy
Johannes Berg8cb08172019-04-26 14:07:28 +0200686 * @validate: validation strictness
687 * @extack: extended ACK pointer
Thomas Grafbfa83a92005-11-10 02:25:51 +0100688 *
689 * Parses a stream of attributes and stores a pointer to each attribute in
Johannes Berg8cb08172019-04-26 14:07:28 +0200690 * the tb array accessible via the attribute type.
691 * Validation is controlled by the @validate parameter.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100692 *
693 * Returns 0 on success or a negative error code.
694 */
Johannes Berg8cb08172019-04-26 14:07:28 +0200695int __nla_parse(struct nlattr **tb, int maxtype,
696 const struct nlattr *head, int len,
697 const struct nla_policy *policy, unsigned int validate,
698 struct netlink_ext_ack *extack)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100699{
Johannes Berg8cb08172019-04-26 14:07:28 +0200700 return __nla_validate_parse(head, len, maxtype, policy, validate,
Johannes Berg7690aa12020-04-30 22:13:06 +0200701 extack, tb, 0);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100702}
Johannes Berg8cb08172019-04-26 14:07:28 +0200703EXPORT_SYMBOL(__nla_parse);
David Aherna5f6cba2018-10-07 20:16:25 -0700704
Thomas Grafbfa83a92005-11-10 02:25:51 +0100705/**
706 * nla_find - Find a specific attribute in a stream of attributes
707 * @head: head of attribute stream
708 * @len: length of attribute stream
709 * @attrtype: type of attribute to look for
710 *
711 * Returns the first attribute in the stream matching the specified type.
712 */
Jan Engelhardt36546542010-11-16 09:52:32 -0800713struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100714{
Jan Engelhardt36546542010-11-16 09:52:32 -0800715 const struct nlattr *nla;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100716 int rem;
717
718 nla_for_each_attr(nla, head, len, rem)
Thomas Graf8f4c1f92007-09-12 14:44:36 +0200719 if (nla_type(nla) == attrtype)
Jan Engelhardt36546542010-11-16 09:52:32 -0800720 return (struct nlattr *)nla;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100721
722 return NULL;
723}
Fabian Frederick6d6a1382014-06-04 16:11:57 -0700724EXPORT_SYMBOL(nla_find);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100725
726/**
Francis Laniel872f6902020-11-15 18:08:06 +0100727 * nla_strscpy - Copy string attribute payload into a sized buffer
Francis Laniel9ca71872020-11-15 18:08:05 +0100728 * @dst: Where to copy the string to.
729 * @nla: Attribute to copy the string from.
730 * @dstsize: Size of destination buffer.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100731 *
732 * Copies at most dstsize - 1 bytes into the destination buffer.
Francis Laniel9ca71872020-11-15 18:08:05 +0100733 * Unlike strlcpy the destination buffer is always padded out.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100734 *
Francis Laniel9ca71872020-11-15 18:08:05 +0100735 * Return:
736 * * srclen - Returns @nla length (not including the trailing %NUL).
737 * * -E2BIG - If @dstsize is 0 or greater than U16_MAX or @nla length greater
738 * than @dstsize.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100739 */
Francis Laniel872f6902020-11-15 18:08:06 +0100740ssize_t nla_strscpy(char *dst, const struct nlattr *nla, size_t dstsize)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100741{
742 size_t srclen = nla_len(nla);
743 char *src = nla_data(nla);
Francis Laniel9ca71872020-11-15 18:08:05 +0100744 ssize_t ret;
745 size_t len;
746
747 if (dstsize == 0 || WARN_ON_ONCE(dstsize > U16_MAX))
748 return -E2BIG;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100749
750 if (srclen > 0 && src[srclen - 1] == '\0')
751 srclen--;
752
Francis Laniel9ca71872020-11-15 18:08:05 +0100753 if (srclen >= dstsize) {
754 len = dstsize - 1;
755 ret = -E2BIG;
756 } else {
757 len = srclen;
758 ret = len;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100759 }
760
Francis Laniel9ca71872020-11-15 18:08:05 +0100761 memcpy(dst, src, len);
762 /* Zero pad end of dst. */
763 memset(dst + len, 0, dstsize - len);
764
765 return ret;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100766}
Francis Laniel872f6902020-11-15 18:08:06 +0100767EXPORT_SYMBOL(nla_strscpy);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100768
769/**
Phil Sutter2cf0c8b2017-07-27 16:56:40 +0200770 * nla_strdup - Copy string attribute payload into a newly allocated buffer
771 * @nla: attribute to copy the string from
772 * @flags: the type of memory to allocate (see kmalloc).
773 *
774 * Returns a pointer to the allocated buffer or NULL on error.
775 */
776char *nla_strdup(const struct nlattr *nla, gfp_t flags)
777{
778 size_t srclen = nla_len(nla);
779 char *src = nla_data(nla), *dst;
780
781 if (srclen > 0 && src[srclen - 1] == '\0')
782 srclen--;
783
784 dst = kmalloc(srclen + 1, flags);
785 if (dst != NULL) {
786 memcpy(dst, src, srclen);
787 dst[srclen] = '\0';
788 }
789 return dst;
790}
791EXPORT_SYMBOL(nla_strdup);
792
793/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100794 * nla_memcpy - Copy a netlink attribute into another memory area
795 * @dest: where to copy to memcpy
796 * @src: netlink attribute to copy from
797 * @count: size of the destination area
798 *
799 * Note: The number of bytes copied is limited by the length of
800 * attribute's payload. memcpy
801 *
802 * Returns the number of bytes copied.
803 */
Patrick McHardyb057efd2008-10-28 11:59:11 -0700804int nla_memcpy(void *dest, const struct nlattr *src, int count)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100805{
806 int minlen = min_t(int, count, nla_len(src));
807
808 memcpy(dest, nla_data(src), minlen);
Jiri Benc5899f042015-03-29 16:05:28 +0200809 if (count > minlen)
810 memset(dest + minlen, 0, count - minlen);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100811
812 return minlen;
813}
Fabian Frederick6d6a1382014-06-04 16:11:57 -0700814EXPORT_SYMBOL(nla_memcpy);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100815
816/**
817 * nla_memcmp - Compare an attribute with sized memory area
818 * @nla: netlink attribute
819 * @data: memory area
820 * @size: size of memory area
821 */
822int nla_memcmp(const struct nlattr *nla, const void *data,
823 size_t size)
824{
825 int d = nla_len(nla) - size;
826
827 if (d == 0)
828 d = memcmp(nla_data(nla), data, size);
829
830 return d;
831}
Fabian Frederick6d6a1382014-06-04 16:11:57 -0700832EXPORT_SYMBOL(nla_memcmp);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100833
834/**
835 * nla_strcmp - Compare a string attribute against a string
836 * @nla: netlink string attribute
837 * @str: another string
838 */
839int nla_strcmp(const struct nlattr *nla, const char *str)
840{
Pablo Neira8b7b9322014-04-01 19:38:44 +0200841 int len = strlen(str);
842 char *buf = nla_data(nla);
843 int attrlen = nla_len(nla);
844 int d;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100845
Maciej Żenczykowski2c16db62021-05-05 09:58:31 -0700846 while (attrlen > 0 && buf[attrlen - 1] == '\0')
Pablo Neira8b7b9322014-04-01 19:38:44 +0200847 attrlen--;
848
849 d = attrlen - len;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100850 if (d == 0)
851 d = memcmp(nla_data(nla), str, len);
852
853 return d;
854}
Fabian Frederick6d6a1382014-06-04 16:11:57 -0700855EXPORT_SYMBOL(nla_strcmp);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100856
Herbert Xu90800212009-03-11 23:18:32 +0800857#ifdef CONFIG_NET
Thomas Grafbfa83a92005-11-10 02:25:51 +0100858/**
859 * __nla_reserve - reserve room for attribute on the skb
860 * @skb: socket buffer to reserve room on
861 * @attrtype: attribute type
862 * @attrlen: length of attribute payload
863 *
864 * Adds a netlink attribute header to a socket buffer and reserves
865 * room for the payload but does not copy it.
866 *
867 * The caller is responsible to ensure that the skb provides enough
868 * tailroom for the attribute header and payload.
869 */
870struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
871{
872 struct nlattr *nla;
873
Johannes Berg4df864c2017-06-16 14:29:21 +0200874 nla = skb_put(skb, nla_total_size(attrlen));
Thomas Grafbfa83a92005-11-10 02:25:51 +0100875 nla->nla_type = attrtype;
876 nla->nla_len = nla_attr_size(attrlen);
877
878 memset((unsigned char *) nla + nla->nla_len, 0, nla_padlen(attrlen));
879
880 return nla;
881}
Herbert Xu90800212009-03-11 23:18:32 +0800882EXPORT_SYMBOL(__nla_reserve);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100883
884/**
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200885 * __nla_reserve_64bit - reserve room for attribute on the skb and align it
886 * @skb: socket buffer to reserve room on
887 * @attrtype: attribute type
888 * @attrlen: length of attribute payload
Nicolas Dichtel11a99572016-04-22 17:31:16 +0200889 * @padattr: attribute type for the padding
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200890 *
891 * Adds a netlink attribute header to a socket buffer and reserves
892 * room for the payload but does not copy it. It also ensure that this
Nicolas Dichtel11a99572016-04-22 17:31:16 +0200893 * attribute will have a 64-bit aligned nla_data() area.
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200894 *
895 * The caller is responsible to ensure that the skb provides enough
896 * tailroom for the attribute header and payload.
897 */
898struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype,
899 int attrlen, int padattr)
900{
Miaohe Lin4718a472020-08-24 23:25:17 -0400901 nla_align_64bit(skb, padattr);
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200902
903 return __nla_reserve(skb, attrtype, attrlen);
904}
905EXPORT_SYMBOL(__nla_reserve_64bit);
906
907/**
Thomas Graffe4944e2006-08-04 23:03:05 -0700908 * __nla_reserve_nohdr - reserve room for attribute without header
909 * @skb: socket buffer to reserve room on
910 * @attrlen: length of attribute payload
911 *
912 * Reserves room for attribute payload without a header.
913 *
914 * The caller is responsible to ensure that the skb provides enough
915 * tailroom for the payload.
916 */
917void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
918{
yuan linyub952f4d2017-06-18 22:52:04 +0800919 return skb_put_zero(skb, NLA_ALIGN(attrlen));
Thomas Graffe4944e2006-08-04 23:03:05 -0700920}
Herbert Xu90800212009-03-11 23:18:32 +0800921EXPORT_SYMBOL(__nla_reserve_nohdr);
Thomas Graffe4944e2006-08-04 23:03:05 -0700922
923/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100924 * nla_reserve - reserve room for attribute on the skb
925 * @skb: socket buffer to reserve room on
926 * @attrtype: attribute type
927 * @attrlen: length of attribute payload
928 *
929 * Adds a netlink attribute header to a socket buffer and reserves
930 * room for the payload but does not copy it.
931 *
932 * Returns NULL if the tailroom of the skb is insufficient to store
933 * the attribute header and payload.
934 */
935struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
936{
937 if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen)))
938 return NULL;
939
940 return __nla_reserve(skb, attrtype, attrlen);
941}
Herbert Xu90800212009-03-11 23:18:32 +0800942EXPORT_SYMBOL(nla_reserve);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100943
944/**
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200945 * nla_reserve_64bit - reserve room for attribute on the skb and align it
946 * @skb: socket buffer to reserve room on
947 * @attrtype: attribute type
948 * @attrlen: length of attribute payload
Nicolas Dichtel11a99572016-04-22 17:31:16 +0200949 * @padattr: attribute type for the padding
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200950 *
951 * Adds a netlink attribute header to a socket buffer and reserves
952 * room for the payload but does not copy it. It also ensure that this
Nicolas Dichtel11a99572016-04-22 17:31:16 +0200953 * attribute will have a 64-bit aligned nla_data() area.
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200954 *
955 * Returns NULL if the tailroom of the skb is insufficient to store
956 * the attribute header and payload.
957 */
958struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype, int attrlen,
959 int padattr)
960{
961 size_t len;
962
963 if (nla_need_padding_for_64bit(skb))
964 len = nla_total_size_64bit(attrlen);
965 else
966 len = nla_total_size(attrlen);
967 if (unlikely(skb_tailroom(skb) < len))
968 return NULL;
969
970 return __nla_reserve_64bit(skb, attrtype, attrlen, padattr);
971}
972EXPORT_SYMBOL(nla_reserve_64bit);
973
974/**
Julius Volz10b595a2008-06-27 20:02:14 -0700975 * nla_reserve_nohdr - reserve room for attribute without header
Thomas Graffe4944e2006-08-04 23:03:05 -0700976 * @skb: socket buffer to reserve room on
Julius Volz10b595a2008-06-27 20:02:14 -0700977 * @attrlen: length of attribute payload
Thomas Graffe4944e2006-08-04 23:03:05 -0700978 *
979 * Reserves room for attribute payload without a header.
980 *
981 * Returns NULL if the tailroom of the skb is insufficient to store
982 * the attribute payload.
983 */
984void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
985{
986 if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
987 return NULL;
988
989 return __nla_reserve_nohdr(skb, attrlen);
990}
Herbert Xu90800212009-03-11 23:18:32 +0800991EXPORT_SYMBOL(nla_reserve_nohdr);
Thomas Graffe4944e2006-08-04 23:03:05 -0700992
993/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100994 * __nla_put - Add a netlink attribute to a socket buffer
995 * @skb: socket buffer to add attribute to
996 * @attrtype: attribute type
997 * @attrlen: length of attribute payload
998 * @data: head of attribute payload
999 *
1000 * The caller is responsible to ensure that the skb provides enough
1001 * tailroom for the attribute header and payload.
1002 */
1003void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
1004 const void *data)
1005{
1006 struct nlattr *nla;
1007
1008 nla = __nla_reserve(skb, attrtype, attrlen);
1009 memcpy(nla_data(nla), data, attrlen);
1010}
Herbert Xu90800212009-03-11 23:18:32 +08001011EXPORT_SYMBOL(__nla_put);
Thomas Grafbfa83a92005-11-10 02:25:51 +01001012
Thomas Graffe4944e2006-08-04 23:03:05 -07001013/**
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +02001014 * __nla_put_64bit - Add a netlink attribute to a socket buffer and align it
1015 * @skb: socket buffer to add attribute to
1016 * @attrtype: attribute type
1017 * @attrlen: length of attribute payload
1018 * @data: head of attribute payload
Nicolas Dichtel11a99572016-04-22 17:31:16 +02001019 * @padattr: attribute type for the padding
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +02001020 *
1021 * The caller is responsible to ensure that the skb provides enough
1022 * tailroom for the attribute header and payload.
1023 */
1024void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
1025 const void *data, int padattr)
1026{
1027 struct nlattr *nla;
1028
1029 nla = __nla_reserve_64bit(skb, attrtype, attrlen, padattr);
1030 memcpy(nla_data(nla), data, attrlen);
1031}
1032EXPORT_SYMBOL(__nla_put_64bit);
1033
1034/**
Thomas Graffe4944e2006-08-04 23:03:05 -07001035 * __nla_put_nohdr - Add a netlink attribute without header
1036 * @skb: socket buffer to add attribute to
1037 * @attrlen: length of attribute payload
1038 * @data: head of attribute payload
1039 *
1040 * The caller is responsible to ensure that the skb provides enough
1041 * tailroom for the attribute payload.
1042 */
1043void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data)
1044{
1045 void *start;
1046
1047 start = __nla_reserve_nohdr(skb, attrlen);
1048 memcpy(start, data, attrlen);
1049}
Herbert Xu90800212009-03-11 23:18:32 +08001050EXPORT_SYMBOL(__nla_put_nohdr);
Thomas Grafbfa83a92005-11-10 02:25:51 +01001051
1052/**
1053 * nla_put - Add a netlink attribute to a socket buffer
1054 * @skb: socket buffer to add attribute to
1055 * @attrtype: attribute type
1056 * @attrlen: length of attribute payload
1057 * @data: head of attribute payload
1058 *
Thomas Grafbc3ed282008-06-03 16:36:54 -07001059 * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
Thomas Grafbfa83a92005-11-10 02:25:51 +01001060 * the attribute header and payload.
1061 */
1062int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
1063{
1064 if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen)))
Thomas Grafbc3ed282008-06-03 16:36:54 -07001065 return -EMSGSIZE;
Thomas Grafbfa83a92005-11-10 02:25:51 +01001066
1067 __nla_put(skb, attrtype, attrlen, data);
1068 return 0;
1069}
Herbert Xu90800212009-03-11 23:18:32 +08001070EXPORT_SYMBOL(nla_put);
Thomas Grafbfa83a92005-11-10 02:25:51 +01001071
Thomas Graffe4944e2006-08-04 23:03:05 -07001072/**
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +02001073 * nla_put_64bit - Add a netlink attribute to a socket buffer and align it
1074 * @skb: socket buffer to add attribute to
1075 * @attrtype: attribute type
1076 * @attrlen: length of attribute payload
1077 * @data: head of attribute payload
Nicolas Dichtel11a99572016-04-22 17:31:16 +02001078 * @padattr: attribute type for the padding
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +02001079 *
1080 * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
1081 * the attribute header and payload.
1082 */
1083int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
1084 const void *data, int padattr)
1085{
1086 size_t len;
1087
1088 if (nla_need_padding_for_64bit(skb))
1089 len = nla_total_size_64bit(attrlen);
1090 else
1091 len = nla_total_size(attrlen);
1092 if (unlikely(skb_tailroom(skb) < len))
1093 return -EMSGSIZE;
1094
1095 __nla_put_64bit(skb, attrtype, attrlen, data, padattr);
1096 return 0;
1097}
1098EXPORT_SYMBOL(nla_put_64bit);
1099
1100/**
Thomas Graffe4944e2006-08-04 23:03:05 -07001101 * nla_put_nohdr - Add a netlink attribute without header
1102 * @skb: socket buffer to add attribute to
1103 * @attrlen: length of attribute payload
1104 * @data: head of attribute payload
1105 *
Thomas Grafbc3ed282008-06-03 16:36:54 -07001106 * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
Thomas Graffe4944e2006-08-04 23:03:05 -07001107 * the attribute payload.
1108 */
1109int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data)
1110{
1111 if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
Thomas Grafbc3ed282008-06-03 16:36:54 -07001112 return -EMSGSIZE;
Thomas Graffe4944e2006-08-04 23:03:05 -07001113
1114 __nla_put_nohdr(skb, attrlen, data);
1115 return 0;
1116}
Herbert Xu90800212009-03-11 23:18:32 +08001117EXPORT_SYMBOL(nla_put_nohdr);
Thomas Grafbfa83a92005-11-10 02:25:51 +01001118
Patrick McHardy01480e12008-01-22 22:10:59 -08001119/**
1120 * nla_append - Add a netlink attribute without header or padding
1121 * @skb: socket buffer to add attribute to
1122 * @attrlen: length of attribute payload
1123 * @data: head of attribute payload
1124 *
Thomas Grafbc3ed282008-06-03 16:36:54 -07001125 * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
Patrick McHardy01480e12008-01-22 22:10:59 -08001126 * the attribute payload.
1127 */
1128int nla_append(struct sk_buff *skb, int attrlen, const void *data)
1129{
1130 if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
Thomas Grafbc3ed282008-06-03 16:36:54 -07001131 return -EMSGSIZE;
Patrick McHardy01480e12008-01-22 22:10:59 -08001132
Johannes Berg59ae1d12017-06-16 14:29:20 +02001133 skb_put_data(skb, data, attrlen);
Patrick McHardy01480e12008-01-22 22:10:59 -08001134 return 0;
1135}
Herbert Xu90800212009-03-11 23:18:32 +08001136EXPORT_SYMBOL(nla_append);
1137#endif