Linux kernel mirror (for testing)
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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_consume() free a netlink message (expected)
45 * nlmsg_free() free a netlink message (drop)
46 *
47 * Message Sending:
48 * nlmsg_multicast() multicast message to several groups
49 * nlmsg_unicast() unicast a message to a single socket
50 * nlmsg_notify() send notification message
51 *
52 * Message Length Calculations:
53 * nlmsg_msg_size(payload) length of message w/o padding
54 * nlmsg_total_size(payload) length of message w/ padding
55 * nlmsg_padlen(payload) length of padding at tail
56 *
57 * Message Payload Access:
58 * nlmsg_data(nlh) head of message payload
59 * nlmsg_len(nlh) length of message payload
60 * nlmsg_attrdata(nlh, hdrlen) head of attributes data
61 * nlmsg_attrlen(nlh, hdrlen) length of attributes data
62 *
63 * Message Parsing:
64 * nlmsg_ok(nlh, remaining) does nlh fit into remaining bytes?
65 * nlmsg_next(nlh, remaining) get next netlink message
66 * nlmsg_parse() parse attributes of a message
67 * nlmsg_find_attr() find an attribute in a message
68 * nlmsg_for_each_msg() loop over all messages
69 * nlmsg_validate() validate netlink message incl. attrs
70 * nlmsg_for_each_attr() loop over all attributes
71 *
72 * Misc:
73 * nlmsg_report() report back to application?
74 *
75 * ------------------------------------------------------------------------
76 * Attributes Interface
77 * ------------------------------------------------------------------------
78 *
79 * Attribute Format:
80 * <------- nla_total_size(payload) ------->
81 * <---- nla_attr_size(payload) ----->
82 * +----------+- - -+- - - - - - - - - +- - -+-------- - -
83 * | Header | Pad | Payload | Pad | Header
84 * +----------+- - -+- - - - - - - - - +- - -+-------- - -
85 * <- nla_len(nla) -> ^
86 * nla_data(nla)----^ |
87 * nla_next(nla)-----------------------------'
88 *
89 * Data Structures:
90 * struct nlattr netlink attribute header
91 *
92 * Attribute Construction:
93 * nla_reserve(skb, type, len) reserve room for an attribute
94 * nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr
95 * nla_put(skb, type, len, data) add attribute to skb
96 * nla_put_nohdr(skb, len, data) add attribute w/o hdr
97 * nla_append(skb, len, data) append data to skb
98 *
99 * Attribute Construction for Basic Types:
100 * nla_put_u8(skb, type, value) add u8 attribute to skb
101 * nla_put_u16(skb, type, value) add u16 attribute to skb
102 * nla_put_u32(skb, type, value) add u32 attribute to skb
103 * nla_put_u64_64bit(skb, type,
104 * value, padattr) add u64 attribute to skb
105 * nla_put_s8(skb, type, value) add s8 attribute to skb
106 * nla_put_s16(skb, type, value) add s16 attribute to skb
107 * nla_put_s32(skb, type, value) add s32 attribute to skb
108 * nla_put_s64(skb, type, value,
109 * padattr) add s64 attribute to skb
110 * nla_put_string(skb, type, str) add string attribute to skb
111 * nla_put_flag(skb, type) add flag attribute to skb
112 * nla_put_msecs(skb, type, jiffies,
113 * padattr) add msecs attribute to skb
114 * nla_put_in_addr(skb, type, addr) add IPv4 address attribute to skb
115 * nla_put_in6_addr(skb, type, addr) add IPv6 address attribute to skb
116 *
117 * Nested Attributes Construction:
118 * nla_nest_start(skb, type) start a nested attribute
119 * nla_nest_end(skb, nla) finalize a nested attribute
120 * nla_nest_cancel(skb, nla) cancel nested attribute construction
121 * nla_put_empty_nest(skb, type) create an empty nest
122 *
123 * Attribute Length Calculations:
124 * nla_attr_size(payload) length of attribute w/o padding
125 * nla_total_size(payload) length of attribute w/ padding
126 * nla_padlen(payload) length of padding
127 *
128 * Attribute Payload Access:
129 * nla_data(nla) head of attribute payload
130 * nla_len(nla) length of attribute payload
131 *
132 * Attribute Payload Access for Basic Types:
133 * nla_get_uint(nla) get payload for a uint attribute
134 * nla_get_sint(nla) get payload for a sint attribute
135 * nla_get_u8(nla) get payload for a u8 attribute
136 * nla_get_u16(nla) get payload for a u16 attribute
137 * nla_get_u32(nla) get payload for a u32 attribute
138 * nla_get_u64(nla) get payload for a u64 attribute
139 * nla_get_s8(nla) get payload for a s8 attribute
140 * nla_get_s16(nla) get payload for a s16 attribute
141 * nla_get_s32(nla) get payload for a s32 attribute
142 * nla_get_s64(nla) get payload for a s64 attribute
143 * nla_get_flag(nla) return 1 if flag is true
144 * nla_get_msecs(nla) get payload for a msecs attribute
145 *
146 * The same functions also exist with _default().
147 *
148 * Attribute Misc:
149 * nla_memcpy(dest, nla, count) copy attribute into memory
150 * nla_memcmp(nla, data, size) compare attribute with memory area
151 * nla_strscpy(dst, nla, size) copy attribute to a sized string
152 * nla_strcmp(nla, str) compare attribute with string
153 *
154 * Attribute Parsing:
155 * nla_ok(nla, remaining) does nla fit into remaining bytes?
156 * nla_next(nla, remaining) get next netlink attribute
157 * nla_validate() validate a stream of attributes
158 * nla_validate_nested() validate a stream of nested attributes
159 * nla_find() find attribute in stream of attributes
160 * nla_find_nested() find attribute in nested attributes
161 * nla_parse() parse and validate stream of attrs
162 * nla_parse_nested() parse nested attributes
163 * nla_for_each_attr() loop over all attributes
164 * nla_for_each_attr_type() loop over all attributes with the
165 * given type
166 * nla_for_each_nested() loop over the nested attributes
167 * nla_for_each_nested_type() loop over the nested attributes with
168 * the given type
169 *=========================================================================
170 */
171
172 /**
173 * Standard attribute types to specify validation policy
174 */
175enum {
176 NLA_UNSPEC,
177 NLA_U8,
178 NLA_U16,
179 NLA_U32,
180 NLA_U64,
181 NLA_STRING,
182 NLA_FLAG,
183 NLA_MSECS,
184 NLA_NESTED,
185 NLA_NESTED_ARRAY,
186 NLA_NUL_STRING,
187 NLA_BINARY,
188 NLA_S8,
189 NLA_S16,
190 NLA_S32,
191 NLA_S64,
192 NLA_BITFIELD32,
193 NLA_REJECT,
194 NLA_BE16,
195 NLA_BE32,
196 NLA_SINT,
197 NLA_UINT,
198 __NLA_TYPE_MAX,
199};
200
201#define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1)
202
203struct netlink_range_validation {
204 u64 min, max;
205};
206
207struct netlink_range_validation_signed {
208 s64 min, max;
209};
210
211enum nla_policy_validation {
212 NLA_VALIDATE_NONE,
213 NLA_VALIDATE_RANGE,
214 NLA_VALIDATE_RANGE_WARN_TOO_LONG,
215 NLA_VALIDATE_MIN,
216 NLA_VALIDATE_MAX,
217 NLA_VALIDATE_MASK,
218 NLA_VALIDATE_RANGE_PTR,
219 NLA_VALIDATE_FUNCTION,
220};
221
222/**
223 * struct nla_policy - attribute validation policy
224 * @type: Type of attribute or NLA_UNSPEC
225 * @validation_type: type of attribute validation done in addition to
226 * type-specific validation (e.g. range, function call), see
227 * &enum nla_policy_validation
228 * @len: Type specific length of payload
229 *
230 * Policies are defined as arrays of this struct, the array must be
231 * accessible by attribute type up to the highest identifier to be expected.
232 *
233 * Meaning of `len' field:
234 * NLA_STRING Maximum length of string
235 * NLA_NUL_STRING Maximum length of string (excluding NUL)
236 * NLA_FLAG Unused
237 * NLA_BINARY Maximum length of attribute payload
238 * (but see also below with the validation type)
239 * NLA_NESTED,
240 * NLA_NESTED_ARRAY Length verification is done by checking len of
241 * nested header (or empty); len field is used if
242 * nested_policy is also used, for the max attr
243 * number in the nested policy.
244 * NLA_SINT, NLA_UINT,
245 * NLA_U8, NLA_U16,
246 * NLA_U32, NLA_U64,
247 * NLA_S8, NLA_S16,
248 * NLA_S32, NLA_S64,
249 * NLA_BE16, NLA_BE32,
250 * NLA_MSECS Leaving the length field zero will verify the
251 * given type fits, using it verifies minimum length
252 * just like "All other"
253 * NLA_BITFIELD32 Unused
254 * NLA_REJECT Unused
255 * All other Minimum length of attribute payload
256 *
257 * Meaning of validation union:
258 * NLA_BITFIELD32 This is a 32-bit bitmap/bitselector attribute and
259 * `bitfield32_valid' is the u32 value of valid flags
260 * NLA_REJECT This attribute is always rejected and `reject_message'
261 * may point to a string to report as the error instead
262 * of the generic one in extended ACK.
263 * NLA_NESTED `nested_policy' to a nested policy to validate, must
264 * also set `len' to the max attribute number. Use the
265 * provided NLA_POLICY_NESTED() macro.
266 * Note that nla_parse() will validate, but of course not
267 * parse, the nested sub-policies.
268 * NLA_NESTED_ARRAY `nested_policy' points to a nested policy to validate,
269 * must also set `len' to the max attribute number. Use
270 * the provided NLA_POLICY_NESTED_ARRAY() macro.
271 * The difference to NLA_NESTED is the structure:
272 * NLA_NESTED has the nested attributes directly inside
273 * while an array has the nested attributes at another
274 * level down and the attribute types directly in the
275 * nesting don't matter.
276 * NLA_UINT,
277 * NLA_U8,
278 * NLA_U16,
279 * NLA_U32,
280 * NLA_U64,
281 * NLA_BE16,
282 * NLA_BE32,
283 * NLA_SINT,
284 * NLA_S8,
285 * NLA_S16,
286 * NLA_S32,
287 * NLA_S64 The `min' and `max' fields are used depending on the
288 * validation_type field, if that is min/max/range then
289 * the min, max or both are used (respectively) to check
290 * the value of the integer attribute.
291 * Note that in the interest of code simplicity and
292 * struct size both limits are s16, so you cannot
293 * enforce a range that doesn't fall within the range
294 * of s16 - do that using the NLA_POLICY_FULL_RANGE()
295 * or NLA_POLICY_FULL_RANGE_SIGNED() macros instead.
296 * Use the NLA_POLICY_MIN(), NLA_POLICY_MAX() and
297 * NLA_POLICY_RANGE() macros.
298 * NLA_UINT,
299 * NLA_U8,
300 * NLA_U16,
301 * NLA_U32,
302 * NLA_U64 If the validation_type field instead is set to
303 * NLA_VALIDATE_RANGE_PTR, `range' must be a pointer
304 * to a struct netlink_range_validation that indicates
305 * the min/max values.
306 * Use NLA_POLICY_FULL_RANGE().
307 * NLA_SINT,
308 * NLA_S8,
309 * NLA_S16,
310 * NLA_S32,
311 * NLA_S64 If the validation_type field instead is set to
312 * NLA_VALIDATE_RANGE_PTR, `range_signed' must be a
313 * pointer to a struct netlink_range_validation_signed
314 * that indicates the min/max values.
315 * Use NLA_POLICY_FULL_RANGE_SIGNED().
316 *
317 * NLA_BINARY If the validation type is like the ones for integers
318 * above, then the min/max length (not value like for
319 * integers) of the attribute is enforced.
320 *
321 * All other Unused - but note that it's a union
322 *
323 * Meaning of `validate' field, use via NLA_POLICY_VALIDATE_FN:
324 * NLA_BINARY Validation function called for the attribute.
325 * All other Unused - but note that it's a union
326 *
327 * Example:
328 *
329 * static const u32 myvalidflags = 0xff231023;
330 *
331 * static const struct nla_policy my_policy[ATTR_MAX+1] = {
332 * [ATTR_FOO] = { .type = NLA_U16 },
333 * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ },
334 * [ATTR_BAZ] = NLA_POLICY_EXACT_LEN(sizeof(struct mystruct)),
335 * [ATTR_GOO] = NLA_POLICY_BITFIELD32(myvalidflags),
336 * };
337 */
338struct nla_policy {
339 u8 type;
340 u8 validation_type;
341 u16 len;
342 union {
343 /**
344 * @strict_start_type: first attribute to validate strictly
345 *
346 * This entry is special, and used for the attribute at index 0
347 * only, and specifies special data about the policy, namely it
348 * specifies the "boundary type" where strict length validation
349 * starts for any attribute types >= this value, also, strict
350 * nesting validation starts here.
351 *
352 * Additionally, it means that NLA_UNSPEC is actually NLA_REJECT
353 * for any types >= this, so need to use NLA_POLICY_MIN_LEN() to
354 * get the previous pure { .len = xyz } behaviour. The advantage
355 * of this is that types not specified in the policy will be
356 * rejected.
357 *
358 * For completely new families it should be set to 1 so that the
359 * validation is enforced for all attributes. For existing ones
360 * it should be set at least when new attributes are added to
361 * the enum used by the policy, and be set to the new value that
362 * was added to enforce strict validation from thereon.
363 */
364 u16 strict_start_type;
365
366 /* private: use NLA_POLICY_*() to set */
367 const u32 bitfield32_valid;
368 const u32 mask;
369 const char *reject_message;
370 const struct nla_policy *nested_policy;
371 const struct netlink_range_validation *range;
372 const struct netlink_range_validation_signed *range_signed;
373 struct {
374 s16 min, max;
375 };
376 int (*validate)(const struct nlattr *attr,
377 struct netlink_ext_ack *extack);
378 };
379};
380
381#define NLA_POLICY_ETH_ADDR NLA_POLICY_EXACT_LEN(ETH_ALEN)
382#define NLA_POLICY_ETH_ADDR_COMPAT NLA_POLICY_EXACT_LEN_WARN(ETH_ALEN)
383
384#define _NLA_POLICY_NESTED(maxattr, policy) \
385 { .type = NLA_NESTED, .nested_policy = policy, .len = maxattr }
386#define _NLA_POLICY_NESTED_ARRAY(maxattr, policy) \
387 { .type = NLA_NESTED_ARRAY, .nested_policy = policy, .len = maxattr }
388#define NLA_POLICY_NESTED(policy) \
389 _NLA_POLICY_NESTED(ARRAY_SIZE(policy) - 1, policy)
390#define NLA_POLICY_NESTED_ARRAY(policy) \
391 _NLA_POLICY_NESTED_ARRAY(ARRAY_SIZE(policy) - 1, policy)
392#define NLA_POLICY_BITFIELD32(valid) \
393 { .type = NLA_BITFIELD32, .bitfield32_valid = valid }
394
395#define __NLA_IS_UINT_TYPE(tp) \
396 (tp == NLA_U8 || tp == NLA_U16 || tp == NLA_U32 || \
397 tp == NLA_U64 || tp == NLA_UINT || \
398 tp == NLA_BE16 || tp == NLA_BE32)
399#define __NLA_IS_SINT_TYPE(tp) \
400 (tp == NLA_S8 || tp == NLA_S16 || tp == NLA_S32 || tp == NLA_S64 || \
401 tp == NLA_SINT)
402
403#define __NLA_ENSURE(condition) BUILD_BUG_ON_ZERO(!(condition))
404#define NLA_ENSURE_UINT_TYPE(tp) \
405 (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp)) + tp)
406#define NLA_ENSURE_UINT_OR_BINARY_TYPE(tp) \
407 (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp) || \
408 tp == NLA_MSECS || \
409 tp == NLA_BINARY) + tp)
410#define NLA_ENSURE_SINT_TYPE(tp) \
411 (__NLA_ENSURE(__NLA_IS_SINT_TYPE(tp)) + tp)
412#define NLA_ENSURE_INT_OR_BINARY_TYPE(tp) \
413 (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp) || \
414 __NLA_IS_SINT_TYPE(tp) || \
415 tp == NLA_MSECS || \
416 tp == NLA_BINARY) + tp)
417#define NLA_ENSURE_NO_VALIDATION_PTR(tp) \
418 (__NLA_ENSURE(tp != NLA_BITFIELD32 && \
419 tp != NLA_REJECT && \
420 tp != NLA_NESTED && \
421 tp != NLA_NESTED_ARRAY) + tp)
422
423#define NLA_POLICY_RANGE(tp, _min, _max) { \
424 .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \
425 .validation_type = NLA_VALIDATE_RANGE, \
426 .min = _min, \
427 .max = _max \
428}
429
430#define NLA_POLICY_FULL_RANGE(tp, _range) { \
431 .type = NLA_ENSURE_UINT_OR_BINARY_TYPE(tp), \
432 .validation_type = NLA_VALIDATE_RANGE_PTR, \
433 .range = _range, \
434}
435
436#define NLA_POLICY_FULL_RANGE_SIGNED(tp, _range) { \
437 .type = NLA_ENSURE_SINT_TYPE(tp), \
438 .validation_type = NLA_VALIDATE_RANGE_PTR, \
439 .range_signed = _range, \
440}
441
442#define NLA_POLICY_MIN(tp, _min) { \
443 .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \
444 .validation_type = NLA_VALIDATE_MIN, \
445 .min = _min, \
446}
447
448#define NLA_POLICY_MAX(tp, _max) { \
449 .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \
450 .validation_type = NLA_VALIDATE_MAX, \
451 .max = _max, \
452}
453
454#define NLA_POLICY_MASK(tp, _mask) { \
455 .type = NLA_ENSURE_UINT_TYPE(tp), \
456 .validation_type = NLA_VALIDATE_MASK, \
457 .mask = _mask, \
458}
459
460#define NLA_POLICY_VALIDATE_FN(tp, fn, ...) { \
461 .type = NLA_ENSURE_NO_VALIDATION_PTR(tp), \
462 .validation_type = NLA_VALIDATE_FUNCTION, \
463 .validate = fn, \
464 .len = __VA_ARGS__ + 0, \
465}
466
467#define NLA_POLICY_EXACT_LEN(_len) NLA_POLICY_RANGE(NLA_BINARY, _len, _len)
468#define NLA_POLICY_EXACT_LEN_WARN(_len) { \
469 .type = NLA_BINARY, \
470 .validation_type = NLA_VALIDATE_RANGE_WARN_TOO_LONG, \
471 .min = _len, \
472 .max = _len \
473}
474#define NLA_POLICY_MIN_LEN(_len) NLA_POLICY_MIN(NLA_BINARY, _len)
475#define NLA_POLICY_MAX_LEN(_len) NLA_POLICY_MAX(NLA_BINARY, _len)
476
477/**
478 * struct nl_info - netlink source information
479 * @nlh: Netlink message header of original request
480 * @nl_net: Network namespace
481 * @portid: Netlink PORTID of requesting application
482 * @skip_notify: Skip netlink notifications to user space
483 * @skip_notify_kernel: Skip selected in-kernel notifications
484 */
485struct nl_info {
486 struct nlmsghdr *nlh;
487 struct net *nl_net;
488 u32 portid;
489 u8 skip_notify:1,
490 skip_notify_kernel:1;
491};
492
493/**
494 * enum netlink_validation - netlink message/attribute validation levels
495 * @NL_VALIDATE_LIBERAL: Old-style "be liberal" validation, not caring about
496 * extra data at the end of the message, attributes being longer than
497 * they should be, or unknown attributes being present.
498 * @NL_VALIDATE_TRAILING: Reject junk data encountered after attribute parsing.
499 * @NL_VALIDATE_MAXTYPE: Reject attributes > max type; Together with _TRAILING
500 * this is equivalent to the old nla_parse_strict()/nlmsg_parse_strict().
501 * @NL_VALIDATE_UNSPEC: Reject attributes with NLA_UNSPEC in the policy.
502 * This can safely be set by the kernel when the given policy has no
503 * NLA_UNSPEC anymore, and can thus be used to ensure policy entries
504 * are enforced going forward.
505 * @NL_VALIDATE_STRICT_ATTRS: strict attribute policy parsing (e.g.
506 * U8, U16, U32 must have exact size, etc.)
507 * @NL_VALIDATE_NESTED: Check that NLA_F_NESTED is set for NLA_NESTED(_ARRAY)
508 * and unset for other policies.
509 */
510enum netlink_validation {
511 NL_VALIDATE_LIBERAL = 0,
512 NL_VALIDATE_TRAILING = BIT(0),
513 NL_VALIDATE_MAXTYPE = BIT(1),
514 NL_VALIDATE_UNSPEC = BIT(2),
515 NL_VALIDATE_STRICT_ATTRS = BIT(3),
516 NL_VALIDATE_NESTED = BIT(4),
517};
518
519#define NL_VALIDATE_DEPRECATED_STRICT (NL_VALIDATE_TRAILING |\
520 NL_VALIDATE_MAXTYPE)
521#define NL_VALIDATE_STRICT (NL_VALIDATE_TRAILING |\
522 NL_VALIDATE_MAXTYPE |\
523 NL_VALIDATE_UNSPEC |\
524 NL_VALIDATE_STRICT_ATTRS |\
525 NL_VALIDATE_NESTED)
526
527int netlink_rcv_skb(struct sk_buff *skb,
528 int (*cb)(struct sk_buff *, struct nlmsghdr *,
529 struct netlink_ext_ack *));
530int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid,
531 unsigned int group, int report, gfp_t flags);
532
533int __nla_validate(const struct nlattr *head, int len, int maxtype,
534 const struct nla_policy *policy, unsigned int validate,
535 struct netlink_ext_ack *extack);
536int __nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
537 int len, const struct nla_policy *policy, unsigned int validate,
538 struct netlink_ext_ack *extack);
539int nla_policy_len(const struct nla_policy *, int);
540struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype);
541ssize_t nla_strscpy(char *dst, const struct nlattr *nla, size_t dstsize);
542char *nla_strdup(const struct nlattr *nla, gfp_t flags);
543int nla_memcpy(void *dest, const struct nlattr *src, int count);
544int nla_memcmp(const struct nlattr *nla, const void *data, size_t size);
545int nla_strcmp(const struct nlattr *nla, const char *str);
546struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen);
547struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype,
548 int attrlen, int padattr);
549void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
550struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen);
551struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype,
552 int attrlen, int padattr);
553void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
554void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
555 const void *data);
556void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
557 const void *data, int padattr);
558void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data);
559int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data);
560int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
561 const void *data, int padattr);
562int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data);
563int nla_append(struct sk_buff *skb, int attrlen, const void *data);
564
565/**************************************************************************
566 * Netlink Messages
567 **************************************************************************/
568
569/**
570 * nlmsg_msg_size - length of netlink message not including padding
571 * @payload: length of message payload
572 */
573static inline int nlmsg_msg_size(int payload)
574{
575 return NLMSG_HDRLEN + payload;
576}
577
578/**
579 * nlmsg_total_size - length of netlink message including padding
580 * @payload: length of message payload
581 */
582static inline int nlmsg_total_size(int payload)
583{
584 return NLMSG_ALIGN(nlmsg_msg_size(payload));
585}
586
587/**
588 * nlmsg_padlen - length of padding at the message's tail
589 * @payload: length of message payload
590 */
591static inline int nlmsg_padlen(int payload)
592{
593 return nlmsg_total_size(payload) - nlmsg_msg_size(payload);
594}
595
596/**
597 * nlmsg_data - head of message payload
598 * @nlh: netlink message header
599 */
600static inline void *nlmsg_data(const struct nlmsghdr *nlh)
601{
602 return (unsigned char *) nlh + NLMSG_HDRLEN;
603}
604
605/**
606 * nlmsg_len - length of message payload
607 * @nlh: netlink message header
608 */
609static inline int nlmsg_len(const struct nlmsghdr *nlh)
610{
611 return nlh->nlmsg_len - NLMSG_HDRLEN;
612}
613
614/**
615 * nlmsg_attrdata - head of attributes data
616 * @nlh: netlink message header
617 * @hdrlen: length of family specific header
618 */
619static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh,
620 int hdrlen)
621{
622 unsigned char *data = nlmsg_data(nlh);
623 return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen));
624}
625
626/**
627 * nlmsg_attrlen - length of attributes data
628 * @nlh: netlink message header
629 * @hdrlen: length of family specific header
630 */
631static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen)
632{
633 return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen);
634}
635
636/**
637 * nlmsg_ok - check if the netlink message fits into the remaining bytes
638 * @nlh: netlink message header
639 * @remaining: number of bytes remaining in message stream
640 */
641static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining)
642{
643 return (remaining >= (int) sizeof(struct nlmsghdr) &&
644 nlh->nlmsg_len >= sizeof(struct nlmsghdr) &&
645 nlh->nlmsg_len <= remaining);
646}
647
648/**
649 * nlmsg_next - next netlink message in message stream
650 * @nlh: netlink message header
651 * @remaining: number of bytes remaining in message stream
652 *
653 * Returns: the next netlink message in the message stream and
654 * decrements remaining by the size of the current message.
655 */
656static inline struct nlmsghdr *
657nlmsg_next(const struct nlmsghdr *nlh, int *remaining)
658{
659 int totlen = NLMSG_ALIGN(nlh->nlmsg_len);
660
661 *remaining -= totlen;
662
663 return (struct nlmsghdr *) ((unsigned char *) nlh + totlen);
664}
665
666/**
667 * nla_parse - Parse a stream of attributes into a tb buffer
668 * @tb: destination array with maxtype+1 elements
669 * @maxtype: maximum attribute type to be expected
670 * @head: head of attribute stream
671 * @len: length of attribute stream
672 * @policy: validation policy
673 * @extack: extended ACK pointer
674 *
675 * Parses a stream of attributes and stores a pointer to each attribute in
676 * the tb array accessible via the attribute type. Attributes with a type
677 * exceeding maxtype will be rejected, policy must be specified, attributes
678 * will be validated in the strictest way possible.
679 *
680 * Returns: 0 on success or a negative error code.
681 */
682static inline int nla_parse(struct nlattr **tb, int maxtype,
683 const struct nlattr *head, int len,
684 const struct nla_policy *policy,
685 struct netlink_ext_ack *extack)
686{
687 return __nla_parse(tb, maxtype, head, len, policy,
688 NL_VALIDATE_STRICT, extack);
689}
690
691/**
692 * nla_parse_deprecated - Parse a stream of attributes into a tb buffer
693 * @tb: destination array with maxtype+1 elements
694 * @maxtype: maximum attribute type to be expected
695 * @head: head of attribute stream
696 * @len: length of attribute stream
697 * @policy: validation policy
698 * @extack: extended ACK pointer
699 *
700 * Parses a stream of attributes and stores a pointer to each attribute in
701 * the tb array accessible via the attribute type. Attributes with a type
702 * exceeding maxtype will be ignored and attributes from the policy are not
703 * always strictly validated (only for new attributes).
704 *
705 * Returns: 0 on success or a negative error code.
706 */
707static inline int nla_parse_deprecated(struct nlattr **tb, int maxtype,
708 const struct nlattr *head, int len,
709 const struct nla_policy *policy,
710 struct netlink_ext_ack *extack)
711{
712 return __nla_parse(tb, maxtype, head, len, policy,
713 NL_VALIDATE_LIBERAL, extack);
714}
715
716/**
717 * nla_parse_deprecated_strict - Parse a stream of attributes into a tb buffer
718 * @tb: destination array with maxtype+1 elements
719 * @maxtype: maximum attribute type to be expected
720 * @head: head of attribute stream
721 * @len: length of attribute stream
722 * @policy: validation policy
723 * @extack: extended ACK pointer
724 *
725 * Parses a stream of attributes and stores a pointer to each attribute in
726 * the tb array accessible via the attribute type. Attributes with a type
727 * exceeding maxtype will be rejected as well as trailing data, but the
728 * policy is not completely strictly validated (only for new attributes).
729 *
730 * Returns: 0 on success or a negative error code.
731 */
732static inline int nla_parse_deprecated_strict(struct nlattr **tb, int maxtype,
733 const struct nlattr *head,
734 int len,
735 const struct nla_policy *policy,
736 struct netlink_ext_ack *extack)
737{
738 return __nla_parse(tb, maxtype, head, len, policy,
739 NL_VALIDATE_DEPRECATED_STRICT, extack);
740}
741
742/**
743 * __nlmsg_parse - parse attributes of a netlink message
744 * @nlh: netlink message header
745 * @hdrlen: length of family specific header
746 * @tb: destination array with maxtype+1 elements
747 * @maxtype: maximum attribute type to be expected
748 * @policy: validation policy
749 * @validate: validation strictness
750 * @extack: extended ACK report struct
751 *
752 * See nla_parse()
753 */
754static inline int __nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen,
755 struct nlattr *tb[], int maxtype,
756 const struct nla_policy *policy,
757 unsigned int validate,
758 struct netlink_ext_ack *extack)
759{
760 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) {
761 NL_SET_ERR_MSG(extack, "Invalid header length");
762 return -EINVAL;
763 }
764
765 return __nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen),
766 nlmsg_attrlen(nlh, hdrlen), policy, validate,
767 extack);
768}
769
770/**
771 * nlmsg_parse - parse attributes of a netlink message
772 * @nlh: netlink message header
773 * @hdrlen: length of family specific header
774 * @tb: destination array with maxtype+1 elements
775 * @maxtype: maximum attribute type to be expected
776 * @policy: validation policy
777 * @extack: extended ACK report struct
778 *
779 * See nla_parse()
780 */
781static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen,
782 struct nlattr *tb[], int maxtype,
783 const struct nla_policy *policy,
784 struct netlink_ext_ack *extack)
785{
786 return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy,
787 NL_VALIDATE_STRICT, extack);
788}
789
790/**
791 * nlmsg_parse_deprecated - parse attributes of a netlink message
792 * @nlh: netlink message header
793 * @hdrlen: length of family specific header
794 * @tb: destination array with maxtype+1 elements
795 * @maxtype: maximum attribute type to be expected
796 * @policy: validation policy
797 * @extack: extended ACK report struct
798 *
799 * See nla_parse_deprecated()
800 */
801static inline int nlmsg_parse_deprecated(const struct nlmsghdr *nlh, int hdrlen,
802 struct nlattr *tb[], int maxtype,
803 const struct nla_policy *policy,
804 struct netlink_ext_ack *extack)
805{
806 return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy,
807 NL_VALIDATE_LIBERAL, extack);
808}
809
810/**
811 * nlmsg_parse_deprecated_strict - parse attributes of a netlink message
812 * @nlh: netlink message header
813 * @hdrlen: length of family specific header
814 * @tb: destination array with maxtype+1 elements
815 * @maxtype: maximum attribute type to be expected
816 * @policy: validation policy
817 * @extack: extended ACK report struct
818 *
819 * See nla_parse_deprecated_strict()
820 */
821static inline int
822nlmsg_parse_deprecated_strict(const struct nlmsghdr *nlh, int hdrlen,
823 struct nlattr *tb[], int maxtype,
824 const struct nla_policy *policy,
825 struct netlink_ext_ack *extack)
826{
827 return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy,
828 NL_VALIDATE_DEPRECATED_STRICT, extack);
829}
830
831/**
832 * nlmsg_find_attr - find a specific attribute in a netlink message
833 * @nlh: netlink message header
834 * @hdrlen: length of family specific header
835 * @attrtype: type of attribute to look for
836 *
837 * Returns: the first attribute which matches the specified type.
838 */
839static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh,
840 int hdrlen, int attrtype)
841{
842 return nla_find(nlmsg_attrdata(nlh, hdrlen),
843 nlmsg_attrlen(nlh, hdrlen), attrtype);
844}
845
846/**
847 * nla_validate_deprecated - Validate a stream of attributes
848 * @head: head of attribute stream
849 * @len: length of attribute stream
850 * @maxtype: maximum attribute type to be expected
851 * @policy: validation policy
852 * @extack: extended ACK report struct
853 *
854 * Validates all attributes in the specified attribute stream against the
855 * specified policy. Validation is done in liberal mode.
856 * See documentation of struct nla_policy for more details.
857 *
858 * Returns: 0 on success or a negative error code.
859 */
860static inline int nla_validate_deprecated(const struct nlattr *head, int len,
861 int maxtype,
862 const struct nla_policy *policy,
863 struct netlink_ext_ack *extack)
864{
865 return __nla_validate(head, len, maxtype, policy, NL_VALIDATE_LIBERAL,
866 extack);
867}
868
869/**
870 * nla_validate - Validate a stream of attributes
871 * @head: head of attribute stream
872 * @len: length of attribute stream
873 * @maxtype: maximum attribute type to be expected
874 * @policy: validation policy
875 * @extack: extended ACK report struct
876 *
877 * Validates all attributes in the specified attribute stream against the
878 * specified policy. Validation is done in strict mode.
879 * See documentation of struct nla_policy for more details.
880 *
881 * Returns: 0 on success or a negative error code.
882 */
883static inline int nla_validate(const struct nlattr *head, int len, int maxtype,
884 const struct nla_policy *policy,
885 struct netlink_ext_ack *extack)
886{
887 return __nla_validate(head, len, maxtype, policy, NL_VALIDATE_STRICT,
888 extack);
889}
890
891/**
892 * nlmsg_validate_deprecated - validate a netlink message including attributes
893 * @nlh: netlinket message header
894 * @hdrlen: length of family specific header
895 * @maxtype: maximum attribute type to be expected
896 * @policy: validation policy
897 * @extack: extended ACK report struct
898 */
899static inline int nlmsg_validate_deprecated(const struct nlmsghdr *nlh,
900 int hdrlen, int maxtype,
901 const struct nla_policy *policy,
902 struct netlink_ext_ack *extack)
903{
904 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
905 return -EINVAL;
906
907 return __nla_validate(nlmsg_attrdata(nlh, hdrlen),
908 nlmsg_attrlen(nlh, hdrlen), maxtype,
909 policy, NL_VALIDATE_LIBERAL, extack);
910}
911
912
913
914/**
915 * nlmsg_report - need to report back to application?
916 * @nlh: netlink message header
917 *
918 * Returns: 1 if a report back to the application is requested.
919 */
920static inline int nlmsg_report(const struct nlmsghdr *nlh)
921{
922 return nlh ? !!(nlh->nlmsg_flags & NLM_F_ECHO) : 0;
923}
924
925/**
926 * nlmsg_seq - return the seq number of netlink message
927 * @nlh: netlink message header
928 *
929 * Returns: 0 if netlink message is NULL
930 */
931static inline u32 nlmsg_seq(const struct nlmsghdr *nlh)
932{
933 return nlh ? nlh->nlmsg_seq : 0;
934}
935
936/**
937 * nlmsg_for_each_attr - iterate over a stream of attributes
938 * @pos: loop counter, set to current attribute
939 * @nlh: netlink message header
940 * @hdrlen: length of family specific header
941 * @rem: initialized to len, holds bytes currently remaining in stream
942 */
943#define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \
944 nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \
945 nlmsg_attrlen(nlh, hdrlen), rem)
946
947/**
948 * nlmsg_put - Add a new netlink message to an skb
949 * @skb: socket buffer to store message in
950 * @portid: netlink PORTID of requesting application
951 * @seq: sequence number of message
952 * @type: message type
953 * @payload: length of message payload
954 * @flags: message flags
955 *
956 * Returns: NULL if the tailroom of the skb is insufficient to store
957 * the message header and payload.
958 */
959static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
960 int type, int payload, int flags)
961{
962 if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload)))
963 return NULL;
964
965 return __nlmsg_put(skb, portid, seq, type, payload, flags);
966}
967
968/**
969 * nlmsg_append - Add more data to a nlmsg in a skb
970 * @skb: socket buffer to store message in
971 * @size: length of message payload
972 *
973 * Append data to an existing nlmsg, used when constructing a message
974 * with multiple fixed-format headers (which is rare).
975 * Returns: NULL if the tailroom of the skb is insufficient to store
976 * the extra payload.
977 */
978static inline void *nlmsg_append(struct sk_buff *skb, u32 size)
979{
980 if (unlikely(skb_tailroom(skb) < NLMSG_ALIGN(size)))
981 return NULL;
982
983 if (NLMSG_ALIGN(size) - size)
984 memset(skb_tail_pointer(skb) + size, 0,
985 NLMSG_ALIGN(size) - size);
986 return __skb_put(skb, NLMSG_ALIGN(size));
987}
988
989/**
990 * nlmsg_put_answer - Add a new callback based netlink message to an skb
991 * @skb: socket buffer to store message in
992 * @cb: netlink callback
993 * @type: message type
994 * @payload: length of message payload
995 * @flags: message flags
996 *
997 * Returns: NULL if the tailroom of the skb is insufficient to store
998 * the message header and payload.
999 */
1000static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb,
1001 struct netlink_callback *cb,
1002 int type, int payload,
1003 int flags)
1004{
1005 return nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1006 type, payload, flags);
1007}
1008
1009/**
1010 * nlmsg_new - Allocate a new netlink message
1011 * @payload: size of the message payload
1012 * @flags: the type of memory to allocate.
1013 *
1014 * Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known
1015 * and a good default is needed.
1016 */
1017static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags)
1018{
1019 return alloc_skb(nlmsg_total_size(payload), flags);
1020}
1021
1022/**
1023 * nlmsg_new_large - Allocate a new netlink message with non-contiguous
1024 * physical memory
1025 * @payload: size of the message payload
1026 *
1027 * The allocated skb is unable to have frag page for shinfo->frags*,
1028 * as the NULL setting for skb->head in netlink_skb_destructor() will
1029 * bypass most of the handling in skb_release_data()
1030 */
1031static inline struct sk_buff *nlmsg_new_large(size_t payload)
1032{
1033 return netlink_alloc_large_skb(nlmsg_total_size(payload), 0);
1034}
1035
1036/**
1037 * nlmsg_end - Finalize a netlink message
1038 * @skb: socket buffer the message is stored in
1039 * @nlh: netlink message header
1040 *
1041 * Corrects the netlink message header to include the appended
1042 * attributes. Only necessary if attributes have been added to
1043 * the message.
1044 */
1045static inline void nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh)
1046{
1047 nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh;
1048}
1049
1050/**
1051 * nlmsg_get_pos - return current position in netlink message
1052 * @skb: socket buffer the message is stored in
1053 *
1054 * Returns: a pointer to the current tail of the message.
1055 */
1056static inline void *nlmsg_get_pos(struct sk_buff *skb)
1057{
1058 return skb_tail_pointer(skb);
1059}
1060
1061/**
1062 * nlmsg_trim - Trim message to a mark
1063 * @skb: socket buffer the message is stored in
1064 * @mark: mark to trim to
1065 *
1066 * Trims the message to the provided mark.
1067 */
1068static inline void nlmsg_trim(struct sk_buff *skb, const void *mark)
1069{
1070 if (mark) {
1071 WARN_ON((unsigned char *) mark < skb->data);
1072 skb_trim(skb, (unsigned char *) mark - skb->data);
1073 }
1074}
1075
1076/**
1077 * nlmsg_cancel - Cancel construction of a netlink message
1078 * @skb: socket buffer the message is stored in
1079 * @nlh: netlink message header
1080 *
1081 * Removes the complete netlink message including all
1082 * attributes from the socket buffer again.
1083 */
1084static inline void nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh)
1085{
1086 nlmsg_trim(skb, nlh);
1087}
1088
1089/**
1090 * nlmsg_free - drop a netlink message
1091 * @skb: socket buffer of netlink message
1092 */
1093static inline void nlmsg_free(struct sk_buff *skb)
1094{
1095 kfree_skb(skb);
1096}
1097
1098/**
1099 * nlmsg_consume - free a netlink message
1100 * @skb: socket buffer of netlink message
1101 */
1102static inline void nlmsg_consume(struct sk_buff *skb)
1103{
1104 consume_skb(skb);
1105}
1106
1107/**
1108 * nlmsg_multicast_filtered - multicast a netlink message with filter function
1109 * @sk: netlink socket to spread messages to
1110 * @skb: netlink message as socket buffer
1111 * @portid: own netlink portid to avoid sending to yourself
1112 * @group: multicast group id
1113 * @flags: allocation flags
1114 * @filter: filter function
1115 * @filter_data: filter function private data
1116 *
1117 * Return: 0 on success, negative error code for failure.
1118 */
1119static inline int nlmsg_multicast_filtered(struct sock *sk, struct sk_buff *skb,
1120 u32 portid, unsigned int group,
1121 gfp_t flags,
1122 netlink_filter_fn filter,
1123 void *filter_data)
1124{
1125 int err;
1126
1127 NETLINK_CB(skb).dst_group = group;
1128
1129 err = netlink_broadcast_filtered(sk, skb, portid, group, flags,
1130 filter, filter_data);
1131 if (err > 0)
1132 err = 0;
1133
1134 return err;
1135}
1136
1137/**
1138 * nlmsg_multicast - multicast a netlink message
1139 * @sk: netlink socket to spread messages to
1140 * @skb: netlink message as socket buffer
1141 * @portid: own netlink portid to avoid sending to yourself
1142 * @group: multicast group id
1143 * @flags: allocation flags
1144 */
1145static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb,
1146 u32 portid, unsigned int group, gfp_t flags)
1147{
1148 return nlmsg_multicast_filtered(sk, skb, portid, group, flags,
1149 NULL, NULL);
1150}
1151
1152/**
1153 * nlmsg_unicast - unicast a netlink message
1154 * @sk: netlink socket to spread message to
1155 * @skb: netlink message as socket buffer
1156 * @portid: netlink portid of the destination socket
1157 */
1158static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 portid)
1159{
1160 int err;
1161
1162 err = netlink_unicast(sk, skb, portid, MSG_DONTWAIT);
1163 if (err > 0)
1164 err = 0;
1165
1166 return err;
1167}
1168
1169/**
1170 * nlmsg_for_each_msg - iterate over a stream of messages
1171 * @pos: loop counter, set to current message
1172 * @head: head of message stream
1173 * @len: length of message stream
1174 * @rem: initialized to len, holds bytes currently remaining in stream
1175 */
1176#define nlmsg_for_each_msg(pos, head, len, rem) \
1177 for (pos = head, rem = len; \
1178 nlmsg_ok(pos, rem); \
1179 pos = nlmsg_next(pos, &(rem)))
1180
1181/**
1182 * nl_dump_check_consistent - check if sequence is consistent and advertise if not
1183 * @cb: netlink callback structure that stores the sequence number
1184 * @nlh: netlink message header to write the flag to
1185 *
1186 * This function checks if the sequence (generation) number changed during dump
1187 * and if it did, advertises it in the netlink message header.
1188 *
1189 * The correct way to use it is to set cb->seq to the generation counter when
1190 * all locks for dumping have been acquired, and then call this function for
1191 * each message that is generated.
1192 *
1193 * Note that due to initialisation concerns, 0 is an invalid sequence number
1194 * and must not be used by code that uses this functionality.
1195 */
1196static inline void
1197nl_dump_check_consistent(struct netlink_callback *cb,
1198 struct nlmsghdr *nlh)
1199{
1200 if (cb->prev_seq && cb->seq != cb->prev_seq)
1201 nlh->nlmsg_flags |= NLM_F_DUMP_INTR;
1202 cb->prev_seq = cb->seq;
1203}
1204
1205/**************************************************************************
1206 * Netlink Attributes
1207 **************************************************************************/
1208
1209/**
1210 * nla_attr_size - length of attribute not including padding
1211 * @payload: length of payload
1212 */
1213static inline int nla_attr_size(int payload)
1214{
1215 return NLA_HDRLEN + payload;
1216}
1217
1218/**
1219 * nla_total_size - total length of attribute including padding
1220 * @payload: length of payload
1221 */
1222static inline int nla_total_size(int payload)
1223{
1224 return NLA_ALIGN(nla_attr_size(payload));
1225}
1226
1227/**
1228 * nla_padlen - length of padding at the tail of attribute
1229 * @payload: length of payload
1230 */
1231static inline int nla_padlen(int payload)
1232{
1233 return nla_total_size(payload) - nla_attr_size(payload);
1234}
1235
1236/**
1237 * nla_type - attribute type
1238 * @nla: netlink attribute
1239 */
1240static inline int nla_type(const struct nlattr *nla)
1241{
1242 return nla->nla_type & NLA_TYPE_MASK;
1243}
1244
1245/**
1246 * nla_data - head of payload
1247 * @nla: netlink attribute
1248 */
1249static inline void *nla_data(const struct nlattr *nla)
1250{
1251 return (char *) nla + NLA_HDRLEN;
1252}
1253
1254/**
1255 * nla_len - length of payload
1256 * @nla: netlink attribute
1257 */
1258static inline u16 nla_len(const struct nlattr *nla)
1259{
1260 return nla->nla_len - NLA_HDRLEN;
1261}
1262
1263/**
1264 * nla_ok - check if the netlink attribute fits into the remaining bytes
1265 * @nla: netlink attribute
1266 * @remaining: number of bytes remaining in attribute stream
1267 */
1268static inline int nla_ok(const struct nlattr *nla, int remaining)
1269{
1270 return remaining >= (int) sizeof(*nla) &&
1271 nla->nla_len >= sizeof(*nla) &&
1272 nla->nla_len <= remaining;
1273}
1274
1275/**
1276 * nla_next - next netlink attribute in attribute stream
1277 * @nla: netlink attribute
1278 * @remaining: number of bytes remaining in attribute stream
1279 *
1280 * Returns: the next netlink attribute in the attribute stream and
1281 * decrements remaining by the size of the current attribute.
1282 */
1283static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining)
1284{
1285 unsigned int totlen = NLA_ALIGN(nla->nla_len);
1286
1287 *remaining -= totlen;
1288 return (struct nlattr *) ((char *) nla + totlen);
1289}
1290
1291/**
1292 * nla_find_nested - find attribute in a set of nested attributes
1293 * @nla: attribute containing the nested attributes
1294 * @attrtype: type of attribute to look for
1295 *
1296 * Returns: the first attribute which matches the specified type.
1297 */
1298static inline struct nlattr *
1299nla_find_nested(const struct nlattr *nla, int attrtype)
1300{
1301 return nla_find(nla_data(nla), nla_len(nla), attrtype);
1302}
1303
1304/**
1305 * nla_parse_nested - parse nested attributes
1306 * @tb: destination array with maxtype+1 elements
1307 * @maxtype: maximum attribute type to be expected
1308 * @nla: attribute containing the nested attributes
1309 * @policy: validation policy
1310 * @extack: extended ACK report struct
1311 *
1312 * See nla_parse()
1313 */
1314static inline int nla_parse_nested(struct nlattr *tb[], int maxtype,
1315 const struct nlattr *nla,
1316 const struct nla_policy *policy,
1317 struct netlink_ext_ack *extack)
1318{
1319 if (!(nla->nla_type & NLA_F_NESTED)) {
1320 NL_SET_ERR_MSG_ATTR(extack, nla, "NLA_F_NESTED is missing");
1321 return -EINVAL;
1322 }
1323
1324 return __nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy,
1325 NL_VALIDATE_STRICT, extack);
1326}
1327
1328/**
1329 * nla_parse_nested_deprecated - parse nested attributes
1330 * @tb: destination array with maxtype+1 elements
1331 * @maxtype: maximum attribute type to be expected
1332 * @nla: attribute containing the nested attributes
1333 * @policy: validation policy
1334 * @extack: extended ACK report struct
1335 *
1336 * See nla_parse_deprecated()
1337 */
1338static inline int nla_parse_nested_deprecated(struct nlattr *tb[], int maxtype,
1339 const struct nlattr *nla,
1340 const struct nla_policy *policy,
1341 struct netlink_ext_ack *extack)
1342{
1343 return __nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy,
1344 NL_VALIDATE_LIBERAL, extack);
1345}
1346
1347/**
1348 * nla_put_u8 - Add a u8 netlink attribute to a socket buffer
1349 * @skb: socket buffer to add attribute to
1350 * @attrtype: attribute type
1351 * @value: numeric value
1352 */
1353static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value)
1354{
1355 /* temporary variables to work around GCC PR81715 with asan-stack=1 */
1356 u8 tmp = value;
1357
1358 return nla_put(skb, attrtype, sizeof(u8), &tmp);
1359}
1360
1361/**
1362 * nla_put_u16 - Add a u16 netlink attribute to a socket buffer
1363 * @skb: socket buffer to add attribute to
1364 * @attrtype: attribute type
1365 * @value: numeric value
1366 */
1367static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value)
1368{
1369 u16 tmp = value;
1370
1371 return nla_put(skb, attrtype, sizeof(u16), &tmp);
1372}
1373
1374/**
1375 * nla_put_be16 - Add a __be16 netlink attribute to a socket buffer
1376 * @skb: socket buffer to add attribute to
1377 * @attrtype: attribute type
1378 * @value: numeric value
1379 */
1380static inline int nla_put_be16(struct sk_buff *skb, int attrtype, __be16 value)
1381{
1382 __be16 tmp = value;
1383
1384 return nla_put(skb, attrtype, sizeof(__be16), &tmp);
1385}
1386
1387/**
1388 * nla_put_net16 - Add 16-bit network byte order netlink attribute to a socket buffer
1389 * @skb: socket buffer to add attribute to
1390 * @attrtype: attribute type
1391 * @value: numeric value
1392 */
1393static inline int nla_put_net16(struct sk_buff *skb, int attrtype, __be16 value)
1394{
1395 __be16 tmp = value;
1396
1397 return nla_put_be16(skb, attrtype | NLA_F_NET_BYTEORDER, tmp);
1398}
1399
1400/**
1401 * nla_put_le16 - Add a __le16 netlink attribute to a socket buffer
1402 * @skb: socket buffer to add attribute to
1403 * @attrtype: attribute type
1404 * @value: numeric value
1405 */
1406static inline int nla_put_le16(struct sk_buff *skb, int attrtype, __le16 value)
1407{
1408 __le16 tmp = value;
1409
1410 return nla_put(skb, attrtype, sizeof(__le16), &tmp);
1411}
1412
1413/**
1414 * nla_put_u32 - Add a u32 netlink attribute to a socket buffer
1415 * @skb: socket buffer to add attribute to
1416 * @attrtype: attribute type
1417 * @value: numeric value
1418 */
1419static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value)
1420{
1421 u32 tmp = value;
1422
1423 return nla_put(skb, attrtype, sizeof(u32), &tmp);
1424}
1425
1426/**
1427 * nla_put_uint - Add a variable-size unsigned int to a socket buffer
1428 * @skb: socket buffer to add attribute to
1429 * @attrtype: attribute type
1430 * @value: numeric value
1431 */
1432static inline int nla_put_uint(struct sk_buff *skb, int attrtype, u64 value)
1433{
1434 u64 tmp64 = value;
1435 u32 tmp32 = value;
1436
1437 if (tmp64 == tmp32)
1438 return nla_put_u32(skb, attrtype, tmp32);
1439 return nla_put(skb, attrtype, sizeof(u64), &tmp64);
1440}
1441
1442/**
1443 * nla_put_be32 - Add a __be32 netlink attribute to a socket buffer
1444 * @skb: socket buffer to add attribute to
1445 * @attrtype: attribute type
1446 * @value: numeric value
1447 */
1448static inline int nla_put_be32(struct sk_buff *skb, int attrtype, __be32 value)
1449{
1450 __be32 tmp = value;
1451
1452 return nla_put(skb, attrtype, sizeof(__be32), &tmp);
1453}
1454
1455/**
1456 * nla_put_net32 - Add 32-bit network byte order netlink attribute to a socket buffer
1457 * @skb: socket buffer to add attribute to
1458 * @attrtype: attribute type
1459 * @value: numeric value
1460 */
1461static inline int nla_put_net32(struct sk_buff *skb, int attrtype, __be32 value)
1462{
1463 __be32 tmp = value;
1464
1465 return nla_put_be32(skb, attrtype | NLA_F_NET_BYTEORDER, tmp);
1466}
1467
1468/**
1469 * nla_put_le32 - Add a __le32 netlink attribute to a socket buffer
1470 * @skb: socket buffer to add attribute to
1471 * @attrtype: attribute type
1472 * @value: numeric value
1473 */
1474static inline int nla_put_le32(struct sk_buff *skb, int attrtype, __le32 value)
1475{
1476 __le32 tmp = value;
1477
1478 return nla_put(skb, attrtype, sizeof(__le32), &tmp);
1479}
1480
1481/**
1482 * nla_put_u64_64bit - Add a u64 netlink attribute to a skb and align it
1483 * @skb: socket buffer to add attribute to
1484 * @attrtype: attribute type
1485 * @value: numeric value
1486 * @padattr: attribute type for the padding
1487 */
1488static inline int nla_put_u64_64bit(struct sk_buff *skb, int attrtype,
1489 u64 value, int padattr)
1490{
1491 u64 tmp = value;
1492
1493 return nla_put_64bit(skb, attrtype, sizeof(u64), &tmp, padattr);
1494}
1495
1496/**
1497 * nla_put_be64 - Add a __be64 netlink attribute to a socket buffer and align it
1498 * @skb: socket buffer to add attribute to
1499 * @attrtype: attribute type
1500 * @value: numeric value
1501 * @padattr: attribute type for the padding
1502 */
1503static inline int nla_put_be64(struct sk_buff *skb, int attrtype, __be64 value,
1504 int padattr)
1505{
1506 __be64 tmp = value;
1507
1508 return nla_put_64bit(skb, attrtype, sizeof(__be64), &tmp, padattr);
1509}
1510
1511/**
1512 * nla_put_net64 - Add 64-bit network byte order nlattr to a skb and align it
1513 * @skb: socket buffer to add attribute to
1514 * @attrtype: attribute type
1515 * @value: numeric value
1516 * @padattr: attribute type for the padding
1517 */
1518static inline int nla_put_net64(struct sk_buff *skb, int attrtype, __be64 value,
1519 int padattr)
1520{
1521 __be64 tmp = value;
1522
1523 return nla_put_be64(skb, attrtype | NLA_F_NET_BYTEORDER, tmp,
1524 padattr);
1525}
1526
1527/**
1528 * nla_put_le64 - Add a __le64 netlink attribute to a socket buffer and align it
1529 * @skb: socket buffer to add attribute to
1530 * @attrtype: attribute type
1531 * @value: numeric value
1532 * @padattr: attribute type for the padding
1533 */
1534static inline int nla_put_le64(struct sk_buff *skb, int attrtype, __le64 value,
1535 int padattr)
1536{
1537 __le64 tmp = value;
1538
1539 return nla_put_64bit(skb, attrtype, sizeof(__le64), &tmp, padattr);
1540}
1541
1542/**
1543 * nla_put_s8 - Add a s8 netlink attribute to a socket buffer
1544 * @skb: socket buffer to add attribute to
1545 * @attrtype: attribute type
1546 * @value: numeric value
1547 */
1548static inline int nla_put_s8(struct sk_buff *skb, int attrtype, s8 value)
1549{
1550 s8 tmp = value;
1551
1552 return nla_put(skb, attrtype, sizeof(s8), &tmp);
1553}
1554
1555/**
1556 * nla_put_s16 - Add a s16 netlink attribute to a socket buffer
1557 * @skb: socket buffer to add attribute to
1558 * @attrtype: attribute type
1559 * @value: numeric value
1560 */
1561static inline int nla_put_s16(struct sk_buff *skb, int attrtype, s16 value)
1562{
1563 s16 tmp = value;
1564
1565 return nla_put(skb, attrtype, sizeof(s16), &tmp);
1566}
1567
1568/**
1569 * nla_put_s32 - Add a s32 netlink attribute to a socket buffer
1570 * @skb: socket buffer to add attribute to
1571 * @attrtype: attribute type
1572 * @value: numeric value
1573 */
1574static inline int nla_put_s32(struct sk_buff *skb, int attrtype, s32 value)
1575{
1576 s32 tmp = value;
1577
1578 return nla_put(skb, attrtype, sizeof(s32), &tmp);
1579}
1580
1581/**
1582 * nla_put_s64 - Add a s64 netlink attribute to a socket buffer and align it
1583 * @skb: socket buffer to add attribute to
1584 * @attrtype: attribute type
1585 * @value: numeric value
1586 * @padattr: attribute type for the padding
1587 */
1588static inline int nla_put_s64(struct sk_buff *skb, int attrtype, s64 value,
1589 int padattr)
1590{
1591 s64 tmp = value;
1592
1593 return nla_put_64bit(skb, attrtype, sizeof(s64), &tmp, padattr);
1594}
1595
1596/**
1597 * nla_put_sint - Add a variable-size signed int to a socket buffer
1598 * @skb: socket buffer to add attribute to
1599 * @attrtype: attribute type
1600 * @value: numeric value
1601 */
1602static inline int nla_put_sint(struct sk_buff *skb, int attrtype, s64 value)
1603{
1604 s64 tmp64 = value;
1605 s32 tmp32 = value;
1606
1607 if (tmp64 == tmp32)
1608 return nla_put_s32(skb, attrtype, tmp32);
1609 return nla_put(skb, attrtype, sizeof(s64), &tmp64);
1610}
1611
1612/**
1613 * nla_put_string - Add a string netlink attribute to a socket buffer
1614 * @skb: socket buffer to add attribute to
1615 * @attrtype: attribute type
1616 * @str: NUL terminated string
1617 */
1618static inline int nla_put_string(struct sk_buff *skb, int attrtype,
1619 const char *str)
1620{
1621 return nla_put(skb, attrtype, strlen(str) + 1, str);
1622}
1623
1624/**
1625 * nla_put_flag - Add a flag netlink attribute to a socket buffer
1626 * @skb: socket buffer to add attribute to
1627 * @attrtype: attribute type
1628 */
1629static inline int nla_put_flag(struct sk_buff *skb, int attrtype)
1630{
1631 return nla_put(skb, attrtype, 0, NULL);
1632}
1633
1634/**
1635 * nla_put_msecs - Add a msecs netlink attribute to a skb and align it
1636 * @skb: socket buffer to add attribute to
1637 * @attrtype: attribute type
1638 * @njiffies: number of jiffies to convert to msecs
1639 * @padattr: attribute type for the padding
1640 */
1641static inline int nla_put_msecs(struct sk_buff *skb, int attrtype,
1642 unsigned long njiffies, int padattr)
1643{
1644 u64 tmp = jiffies_to_msecs(njiffies);
1645
1646 return nla_put_64bit(skb, attrtype, sizeof(u64), &tmp, padattr);
1647}
1648
1649/**
1650 * nla_put_in_addr - Add an IPv4 address netlink attribute to a socket
1651 * buffer
1652 * @skb: socket buffer to add attribute to
1653 * @attrtype: attribute type
1654 * @addr: IPv4 address
1655 */
1656static inline int nla_put_in_addr(struct sk_buff *skb, int attrtype,
1657 __be32 addr)
1658{
1659 __be32 tmp = addr;
1660
1661 return nla_put_be32(skb, attrtype, tmp);
1662}
1663
1664/**
1665 * nla_put_in6_addr - Add an IPv6 address netlink attribute to a socket
1666 * buffer
1667 * @skb: socket buffer to add attribute to
1668 * @attrtype: attribute type
1669 * @addr: IPv6 address
1670 */
1671static inline int nla_put_in6_addr(struct sk_buff *skb, int attrtype,
1672 const struct in6_addr *addr)
1673{
1674 return nla_put(skb, attrtype, sizeof(*addr), addr);
1675}
1676
1677/**
1678 * nla_put_bitfield32 - Add a bitfield32 netlink attribute to a socket buffer
1679 * @skb: socket buffer to add attribute to
1680 * @attrtype: attribute type
1681 * @value: value carrying bits
1682 * @selector: selector of valid bits
1683 */
1684static inline int nla_put_bitfield32(struct sk_buff *skb, int attrtype,
1685 __u32 value, __u32 selector)
1686{
1687 struct nla_bitfield32 tmp = { value, selector, };
1688
1689 return nla_put(skb, attrtype, sizeof(tmp), &tmp);
1690}
1691
1692/**
1693 * nla_get_u32 - return payload of u32 attribute
1694 * @nla: u32 netlink attribute
1695 */
1696static inline u32 nla_get_u32(const struct nlattr *nla)
1697{
1698 return *(u32 *) nla_data(nla);
1699}
1700
1701/**
1702 * nla_get_u32_default - return payload of u32 attribute or default
1703 * @nla: u32 netlink attribute, may be %NULL
1704 * @defvalue: default value to use if @nla is %NULL
1705 *
1706 * Return: the value of the attribute, or the default value if not present
1707 */
1708static inline u32 nla_get_u32_default(const struct nlattr *nla, u32 defvalue)
1709{
1710 if (!nla)
1711 return defvalue;
1712 return nla_get_u32(nla);
1713}
1714
1715/**
1716 * nla_get_be32 - return payload of __be32 attribute
1717 * @nla: __be32 netlink attribute
1718 */
1719static inline __be32 nla_get_be32(const struct nlattr *nla)
1720{
1721 return *(__be32 *) nla_data(nla);
1722}
1723
1724/**
1725 * nla_get_be32_default - return payload of be32 attribute or default
1726 * @nla: __be32 netlink attribute, may be %NULL
1727 * @defvalue: default value to use if @nla is %NULL
1728 *
1729 * Return: the value of the attribute, or the default value if not present
1730 */
1731static inline __be32 nla_get_be32_default(const struct nlattr *nla,
1732 __be32 defvalue)
1733{
1734 if (!nla)
1735 return defvalue;
1736 return nla_get_be32(nla);
1737}
1738
1739/**
1740 * nla_get_le32 - return payload of __le32 attribute
1741 * @nla: __le32 netlink attribute
1742 */
1743static inline __le32 nla_get_le32(const struct nlattr *nla)
1744{
1745 return *(__le32 *) nla_data(nla);
1746}
1747
1748/**
1749 * nla_get_le32_default - return payload of le32 attribute or default
1750 * @nla: __le32 netlink attribute, may be %NULL
1751 * @defvalue: default value to use if @nla is %NULL
1752 *
1753 * Return: the value of the attribute, or the default value if not present
1754 */
1755static inline __le32 nla_get_le32_default(const struct nlattr *nla,
1756 __le32 defvalue)
1757{
1758 if (!nla)
1759 return defvalue;
1760 return nla_get_le32(nla);
1761}
1762
1763/**
1764 * nla_get_u16 - return payload of u16 attribute
1765 * @nla: u16 netlink attribute
1766 */
1767static inline u16 nla_get_u16(const struct nlattr *nla)
1768{
1769 return *(u16 *) nla_data(nla);
1770}
1771
1772/**
1773 * nla_get_u16_default - return payload of u16 attribute or default
1774 * @nla: u16 netlink attribute, may be %NULL
1775 * @defvalue: default value to use if @nla is %NULL
1776 *
1777 * Return: the value of the attribute, or the default value if not present
1778 */
1779static inline u16 nla_get_u16_default(const struct nlattr *nla, u16 defvalue)
1780{
1781 if (!nla)
1782 return defvalue;
1783 return nla_get_u16(nla);
1784}
1785
1786/**
1787 * nla_get_be16 - return payload of __be16 attribute
1788 * @nla: __be16 netlink attribute
1789 */
1790static inline __be16 nla_get_be16(const struct nlattr *nla)
1791{
1792 return *(__be16 *) nla_data(nla);
1793}
1794
1795/**
1796 * nla_get_be16_default - return payload of be16 attribute or default
1797 * @nla: __be16 netlink attribute, may be %NULL
1798 * @defvalue: default value to use if @nla is %NULL
1799 *
1800 * Return: the value of the attribute, or the default value if not present
1801 */
1802static inline __be16 nla_get_be16_default(const struct nlattr *nla,
1803 __be16 defvalue)
1804{
1805 if (!nla)
1806 return defvalue;
1807 return nla_get_be16(nla);
1808}
1809
1810/**
1811 * nla_get_le16 - return payload of __le16 attribute
1812 * @nla: __le16 netlink attribute
1813 */
1814static inline __le16 nla_get_le16(const struct nlattr *nla)
1815{
1816 return *(__le16 *) nla_data(nla);
1817}
1818
1819/**
1820 * nla_get_le16_default - return payload of le16 attribute or default
1821 * @nla: __le16 netlink attribute, may be %NULL
1822 * @defvalue: default value to use if @nla is %NULL
1823 *
1824 * Return: the value of the attribute, or the default value if not present
1825 */
1826static inline __le16 nla_get_le16_default(const struct nlattr *nla,
1827 __le16 defvalue)
1828{
1829 if (!nla)
1830 return defvalue;
1831 return nla_get_le16(nla);
1832}
1833
1834/**
1835 * nla_get_u8 - return payload of u8 attribute
1836 * @nla: u8 netlink attribute
1837 */
1838static inline u8 nla_get_u8(const struct nlattr *nla)
1839{
1840 return *(u8 *) nla_data(nla);
1841}
1842
1843/**
1844 * nla_get_u8_default - return payload of u8 attribute or default
1845 * @nla: u8 netlink attribute, may be %NULL
1846 * @defvalue: default value to use if @nla is %NULL
1847 *
1848 * Return: the value of the attribute, or the default value if not present
1849 */
1850static inline u8 nla_get_u8_default(const struct nlattr *nla, u8 defvalue)
1851{
1852 if (!nla)
1853 return defvalue;
1854 return nla_get_u8(nla);
1855}
1856
1857/**
1858 * nla_get_u64 - return payload of u64 attribute
1859 * @nla: u64 netlink attribute
1860 */
1861static inline u64 nla_get_u64(const struct nlattr *nla)
1862{
1863 u64 tmp;
1864
1865 nla_memcpy(&tmp, nla, sizeof(tmp));
1866
1867 return tmp;
1868}
1869
1870/**
1871 * nla_get_u64_default - return payload of u64 attribute or default
1872 * @nla: u64 netlink attribute, may be %NULL
1873 * @defvalue: default value to use if @nla is %NULL
1874 *
1875 * Return: the value of the attribute, or the default value if not present
1876 */
1877static inline u64 nla_get_u64_default(const struct nlattr *nla, u64 defvalue)
1878{
1879 if (!nla)
1880 return defvalue;
1881 return nla_get_u64(nla);
1882}
1883
1884/**
1885 * nla_get_uint - return payload of uint attribute
1886 * @nla: uint netlink attribute
1887 */
1888static inline u64 nla_get_uint(const struct nlattr *nla)
1889{
1890 if (nla_len(nla) == sizeof(u32))
1891 return nla_get_u32(nla);
1892 return nla_get_u64(nla);
1893}
1894
1895/**
1896 * nla_get_uint_default - return payload of uint attribute or default
1897 * @nla: uint netlink attribute, may be %NULL
1898 * @defvalue: default value to use if @nla is %NULL
1899 *
1900 * Return: the value of the attribute, or the default value if not present
1901 */
1902static inline u64 nla_get_uint_default(const struct nlattr *nla, u64 defvalue)
1903{
1904 if (!nla)
1905 return defvalue;
1906 return nla_get_uint(nla);
1907}
1908
1909/**
1910 * nla_get_be64 - return payload of __be64 attribute
1911 * @nla: __be64 netlink attribute
1912 */
1913static inline __be64 nla_get_be64(const struct nlattr *nla)
1914{
1915 __be64 tmp;
1916
1917 nla_memcpy(&tmp, nla, sizeof(tmp));
1918
1919 return tmp;
1920}
1921
1922/**
1923 * nla_get_be64_default - return payload of be64 attribute or default
1924 * @nla: __be64 netlink attribute, may be %NULL
1925 * @defvalue: default value to use if @nla is %NULL
1926 *
1927 * Return: the value of the attribute, or the default value if not present
1928 */
1929static inline __be64 nla_get_be64_default(const struct nlattr *nla,
1930 __be64 defvalue)
1931{
1932 if (!nla)
1933 return defvalue;
1934 return nla_get_be64(nla);
1935}
1936
1937/**
1938 * nla_get_le64 - return payload of __le64 attribute
1939 * @nla: __le64 netlink attribute
1940 */
1941static inline __le64 nla_get_le64(const struct nlattr *nla)
1942{
1943 return *(__le64 *) nla_data(nla);
1944}
1945
1946/**
1947 * nla_get_le64_default - return payload of le64 attribute or default
1948 * @nla: __le64 netlink attribute, may be %NULL
1949 * @defvalue: default value to use if @nla is %NULL
1950 *
1951 * Return: the value of the attribute, or the default value if not present
1952 */
1953static inline __le64 nla_get_le64_default(const struct nlattr *nla,
1954 __le64 defvalue)
1955{
1956 if (!nla)
1957 return defvalue;
1958 return nla_get_le64(nla);
1959}
1960
1961/**
1962 * nla_get_s32 - return payload of s32 attribute
1963 * @nla: s32 netlink attribute
1964 */
1965static inline s32 nla_get_s32(const struct nlattr *nla)
1966{
1967 return *(s32 *) nla_data(nla);
1968}
1969
1970/**
1971 * nla_get_s32_default - return payload of s32 attribute or default
1972 * @nla: s32 netlink attribute, may be %NULL
1973 * @defvalue: default value to use if @nla is %NULL
1974 *
1975 * Return: the value of the attribute, or the default value if not present
1976 */
1977static inline s32 nla_get_s32_default(const struct nlattr *nla, s32 defvalue)
1978{
1979 if (!nla)
1980 return defvalue;
1981 return nla_get_s32(nla);
1982}
1983
1984/**
1985 * nla_get_s16 - return payload of s16 attribute
1986 * @nla: s16 netlink attribute
1987 */
1988static inline s16 nla_get_s16(const struct nlattr *nla)
1989{
1990 return *(s16 *) nla_data(nla);
1991}
1992
1993/**
1994 * nla_get_s16_default - return payload of s16 attribute or default
1995 * @nla: s16 netlink attribute, may be %NULL
1996 * @defvalue: default value to use if @nla is %NULL
1997 *
1998 * Return: the value of the attribute, or the default value if not present
1999 */
2000static inline s16 nla_get_s16_default(const struct nlattr *nla, s16 defvalue)
2001{
2002 if (!nla)
2003 return defvalue;
2004 return nla_get_s16(nla);
2005}
2006
2007/**
2008 * nla_get_s8 - return payload of s8 attribute
2009 * @nla: s8 netlink attribute
2010 */
2011static inline s8 nla_get_s8(const struct nlattr *nla)
2012{
2013 return *(s8 *) nla_data(nla);
2014}
2015
2016/**
2017 * nla_get_s8_default - return payload of s8 attribute or default
2018 * @nla: s8 netlink attribute, may be %NULL
2019 * @defvalue: default value to use if @nla is %NULL
2020 *
2021 * Return: the value of the attribute, or the default value if not present
2022 */
2023static inline s8 nla_get_s8_default(const struct nlattr *nla, s8 defvalue)
2024{
2025 if (!nla)
2026 return defvalue;
2027 return nla_get_s8(nla);
2028}
2029
2030/**
2031 * nla_get_s64 - return payload of s64 attribute
2032 * @nla: s64 netlink attribute
2033 */
2034static inline s64 nla_get_s64(const struct nlattr *nla)
2035{
2036 s64 tmp;
2037
2038 nla_memcpy(&tmp, nla, sizeof(tmp));
2039
2040 return tmp;
2041}
2042
2043/**
2044 * nla_get_s64_default - return payload of s64 attribute or default
2045 * @nla: s64 netlink attribute, may be %NULL
2046 * @defvalue: default value to use if @nla is %NULL
2047 *
2048 * Return: the value of the attribute, or the default value if not present
2049 */
2050static inline s64 nla_get_s64_default(const struct nlattr *nla, s64 defvalue)
2051{
2052 if (!nla)
2053 return defvalue;
2054 return nla_get_s64(nla);
2055}
2056
2057/**
2058 * nla_get_sint - return payload of uint attribute
2059 * @nla: uint netlink attribute
2060 */
2061static inline s64 nla_get_sint(const struct nlattr *nla)
2062{
2063 if (nla_len(nla) == sizeof(s32))
2064 return nla_get_s32(nla);
2065 return nla_get_s64(nla);
2066}
2067
2068/**
2069 * nla_get_sint_default - return payload of sint attribute or default
2070 * @nla: sint netlink attribute, may be %NULL
2071 * @defvalue: default value to use if @nla is %NULL
2072 *
2073 * Return: the value of the attribute, or the default value if not present
2074 */
2075static inline s64 nla_get_sint_default(const struct nlattr *nla, s64 defvalue)
2076{
2077 if (!nla)
2078 return defvalue;
2079 return nla_get_sint(nla);
2080}
2081
2082/**
2083 * nla_get_flag - return payload of flag attribute
2084 * @nla: flag netlink attribute
2085 */
2086static inline int nla_get_flag(const struct nlattr *nla)
2087{
2088 return !!nla;
2089}
2090
2091/**
2092 * nla_get_msecs - return payload of msecs attribute
2093 * @nla: msecs netlink attribute
2094 *
2095 * Returns: the number of milliseconds in jiffies.
2096 */
2097static inline unsigned long nla_get_msecs(const struct nlattr *nla)
2098{
2099 u64 msecs = nla_get_u64(nla);
2100
2101 return msecs_to_jiffies((unsigned long) msecs);
2102}
2103
2104/**
2105 * nla_get_msecs_default - return payload of msecs attribute or default
2106 * @nla: msecs netlink attribute, may be %NULL
2107 * @defvalue: default value to use if @nla is %NULL
2108 *
2109 * Return: the value of the attribute, or the default value if not present
2110 */
2111static inline unsigned long nla_get_msecs_default(const struct nlattr *nla,
2112 unsigned long defvalue)
2113{
2114 if (!nla)
2115 return defvalue;
2116 return nla_get_msecs(nla);
2117}
2118
2119/**
2120 * nla_get_in_addr - return payload of IPv4 address attribute
2121 * @nla: IPv4 address netlink attribute
2122 */
2123static inline __be32 nla_get_in_addr(const struct nlattr *nla)
2124{
2125 return *(__be32 *) nla_data(nla);
2126}
2127
2128/**
2129 * nla_get_in_addr_default - return payload of be32 attribute or default
2130 * @nla: IPv4 address netlink attribute, may be %NULL
2131 * @defvalue: default value to use if @nla is %NULL
2132 *
2133 * Return: the value of the attribute, or the default value if not present
2134 */
2135static inline __be32 nla_get_in_addr_default(const struct nlattr *nla,
2136 __be32 defvalue)
2137{
2138 if (!nla)
2139 return defvalue;
2140 return nla_get_in_addr(nla);
2141}
2142
2143/**
2144 * nla_get_in6_addr - return payload of IPv6 address attribute
2145 * @nla: IPv6 address netlink attribute
2146 */
2147static inline struct in6_addr nla_get_in6_addr(const struct nlattr *nla)
2148{
2149 struct in6_addr tmp;
2150
2151 nla_memcpy(&tmp, nla, sizeof(tmp));
2152 return tmp;
2153}
2154
2155/**
2156 * nla_get_bitfield32 - return payload of 32 bitfield attribute
2157 * @nla: nla_bitfield32 attribute
2158 */
2159static inline struct nla_bitfield32 nla_get_bitfield32(const struct nlattr *nla)
2160{
2161 struct nla_bitfield32 tmp;
2162
2163 nla_memcpy(&tmp, nla, sizeof(tmp));
2164 return tmp;
2165}
2166
2167/**
2168 * nla_memdup - duplicate attribute memory (kmemdup)
2169 * @src: netlink attribute to duplicate from
2170 * @gfp: GFP mask
2171 */
2172static inline void *nla_memdup_noprof(const struct nlattr *src, gfp_t gfp)
2173{
2174 return kmemdup_noprof(nla_data(src), nla_len(src), gfp);
2175}
2176#define nla_memdup(...) alloc_hooks(nla_memdup_noprof(__VA_ARGS__))
2177
2178/**
2179 * nla_nest_start_noflag - Start a new level of nested attributes
2180 * @skb: socket buffer to add attributes to
2181 * @attrtype: attribute type of container
2182 *
2183 * This function exists for backward compatibility to use in APIs which never
2184 * marked their nest attributes with NLA_F_NESTED flag. New APIs should use
2185 * nla_nest_start() which sets the flag.
2186 *
2187 * Returns: the container attribute or NULL on error
2188 */
2189static inline struct nlattr *nla_nest_start_noflag(struct sk_buff *skb,
2190 int attrtype)
2191{
2192 struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb);
2193
2194 if (nla_put(skb, attrtype, 0, NULL) < 0)
2195 return NULL;
2196
2197 return start;
2198}
2199
2200/**
2201 * nla_nest_start - Start a new level of nested attributes, with NLA_F_NESTED
2202 * @skb: socket buffer to add attributes to
2203 * @attrtype: attribute type of container
2204 *
2205 * Unlike nla_nest_start_noflag(), mark the nest attribute with NLA_F_NESTED
2206 * flag. This is the preferred function to use in new code.
2207 *
2208 * Returns: the container attribute or NULL on error
2209 */
2210static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
2211{
2212 return nla_nest_start_noflag(skb, attrtype | NLA_F_NESTED);
2213}
2214
2215/**
2216 * nla_nest_end - Finalize nesting of attributes
2217 * @skb: socket buffer the attributes are stored in
2218 * @start: container attribute
2219 *
2220 * Corrects the container attribute header to include the all
2221 * appended attributes.
2222 *
2223 * Returns: the total data length of the skb.
2224 */
2225static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start)
2226{
2227 start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start;
2228 return skb->len;
2229}
2230
2231/**
2232 * nla_nest_cancel - Cancel nesting of attributes
2233 * @skb: socket buffer the message is stored in
2234 * @start: container attribute
2235 *
2236 * Removes the container attribute and including all nested
2237 * attributes. Returns -EMSGSIZE
2238 */
2239static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start)
2240{
2241 nlmsg_trim(skb, start);
2242}
2243
2244/**
2245 * nla_put_empty_nest - Create an empty nest
2246 * @skb: socket buffer the message is stored in
2247 * @attrtype: attribute type of the container
2248 *
2249 * This function is a helper for creating empty nests.
2250 *
2251 * Returns: 0 when successful or -EMSGSIZE on failure.
2252 */
2253static inline int nla_put_empty_nest(struct sk_buff *skb, int attrtype)
2254{
2255 return nla_nest_start(skb, attrtype) ? 0 : -EMSGSIZE;
2256}
2257
2258/**
2259 * __nla_validate_nested - Validate a stream of nested attributes
2260 * @start: container attribute
2261 * @maxtype: maximum attribute type to be expected
2262 * @policy: validation policy
2263 * @validate: validation strictness
2264 * @extack: extended ACK report struct
2265 *
2266 * Validates all attributes in the nested attribute stream against the
2267 * specified policy. Attributes with a type exceeding maxtype will be
2268 * ignored. See documentation of struct nla_policy for more details.
2269 *
2270 * Returns: 0 on success or a negative error code.
2271 */
2272static inline int __nla_validate_nested(const struct nlattr *start, int maxtype,
2273 const struct nla_policy *policy,
2274 unsigned int validate,
2275 struct netlink_ext_ack *extack)
2276{
2277 return __nla_validate(nla_data(start), nla_len(start), maxtype, policy,
2278 validate, extack);
2279}
2280
2281static inline int
2282nla_validate_nested(const struct nlattr *start, int maxtype,
2283 const struct nla_policy *policy,
2284 struct netlink_ext_ack *extack)
2285{
2286 return __nla_validate_nested(start, maxtype, policy,
2287 NL_VALIDATE_STRICT, extack);
2288}
2289
2290static inline int
2291nla_validate_nested_deprecated(const struct nlattr *start, int maxtype,
2292 const struct nla_policy *policy,
2293 struct netlink_ext_ack *extack)
2294{
2295 return __nla_validate_nested(start, maxtype, policy,
2296 NL_VALIDATE_LIBERAL, extack);
2297}
2298
2299/**
2300 * nla_need_padding_for_64bit - test 64-bit alignment of the next attribute
2301 * @skb: socket buffer the message is stored in
2302 *
2303 * Return: true if padding is needed to align the next attribute (nla_data()) to
2304 * a 64-bit aligned area.
2305 */
2306static inline bool nla_need_padding_for_64bit(struct sk_buff *skb)
2307{
2308#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2309 /* The nlattr header is 4 bytes in size, that's why we test
2310 * if the skb->data _is_ aligned. A NOP attribute, plus
2311 * nlattr header for next attribute, will make nla_data()
2312 * 8-byte aligned.
2313 */
2314 if (IS_ALIGNED((unsigned long)skb_tail_pointer(skb), 8))
2315 return true;
2316#endif
2317 return false;
2318}
2319
2320/**
2321 * nla_align_64bit - 64-bit align the nla_data() of next attribute
2322 * @skb: socket buffer the message is stored in
2323 * @padattr: attribute type for the padding
2324 *
2325 * Conditionally emit a padding netlink attribute in order to make
2326 * the next attribute we emit have a 64-bit aligned nla_data() area.
2327 * This will only be done in architectures which do not have
2328 * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS defined.
2329 *
2330 * Returns: zero on success or a negative error code.
2331 */
2332static inline int nla_align_64bit(struct sk_buff *skb, int padattr)
2333{
2334 if (nla_need_padding_for_64bit(skb) &&
2335 !nla_reserve(skb, padattr, 0))
2336 return -EMSGSIZE;
2337
2338 return 0;
2339}
2340
2341/**
2342 * nla_total_size_64bit - total length of attribute including padding
2343 * @payload: length of payload
2344 */
2345static inline int nla_total_size_64bit(int payload)
2346{
2347 return NLA_ALIGN(nla_attr_size(payload))
2348#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2349 + NLA_ALIGN(nla_attr_size(0))
2350#endif
2351 ;
2352}
2353
2354/**
2355 * nla_for_each_attr - iterate over a stream of attributes
2356 * @pos: loop counter, set to current attribute
2357 * @head: head of attribute stream
2358 * @len: length of attribute stream
2359 * @rem: initialized to len, holds bytes currently remaining in stream
2360 */
2361#define nla_for_each_attr(pos, head, len, rem) \
2362 for (pos = head, rem = len; \
2363 nla_ok(pos, rem); \
2364 pos = nla_next(pos, &(rem)))
2365
2366/**
2367 * nla_for_each_attr_type - iterate over a stream of attributes
2368 * @pos: loop counter, set to current attribute
2369 * @type: required attribute type for @pos
2370 * @head: head of attribute stream
2371 * @len: length of attribute stream
2372 * @rem: initialized to len, holds bytes currently remaining in stream
2373 */
2374#define nla_for_each_attr_type(pos, type, head, len, rem) \
2375 nla_for_each_attr(pos, head, len, rem) \
2376 if (nla_type(pos) == type)
2377
2378/**
2379 * nla_for_each_nested - iterate over nested attributes
2380 * @pos: loop counter, set to current attribute
2381 * @nla: attribute containing the nested attributes
2382 * @rem: initialized to len, holds bytes currently remaining in stream
2383 */
2384#define nla_for_each_nested(pos, nla, rem) \
2385 nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)
2386
2387/**
2388 * nla_for_each_nested_type - iterate over nested attributes
2389 * @pos: loop counter, set to current attribute
2390 * @type: required attribute type for @pos
2391 * @nla: attribute containing the nested attributes
2392 * @rem: initialized to len, holds bytes currently remaining in stream
2393 */
2394#define nla_for_each_nested_type(pos, type, nla, rem) \
2395 nla_for_each_nested(pos, nla, rem) \
2396 if (nla_type(pos) == type)
2397
2398/**
2399 * nla_is_last - Test if attribute is last in stream
2400 * @nla: attribute to test
2401 * @rem: bytes remaining in stream
2402 */
2403static inline bool nla_is_last(const struct nlattr *nla, int rem)
2404{
2405 return nla->nla_len == rem;
2406}
2407
2408void nla_get_range_unsigned(const struct nla_policy *pt,
2409 struct netlink_range_validation *range);
2410void nla_get_range_signed(const struct nla_policy *pt,
2411 struct netlink_range_validation_signed *range);
2412
2413struct netlink_policy_dump_state;
2414
2415int netlink_policy_dump_add_policy(struct netlink_policy_dump_state **pstate,
2416 const struct nla_policy *policy,
2417 unsigned int maxtype);
2418int netlink_policy_dump_get_policy_idx(struct netlink_policy_dump_state *state,
2419 const struct nla_policy *policy,
2420 unsigned int maxtype);
2421bool netlink_policy_dump_loop(struct netlink_policy_dump_state *state);
2422int netlink_policy_dump_write(struct sk_buff *skb,
2423 struct netlink_policy_dump_state *state);
2424int netlink_policy_dump_attr_size_estimate(const struct nla_policy *pt);
2425int netlink_policy_dump_write_attr(struct sk_buff *skb,
2426 const struct nla_policy *pt,
2427 int nestattr);
2428void netlink_policy_dump_free(struct netlink_policy_dump_state *state);
2429
2430#endif