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1 | #ifndef __NET_NETLINK_H | |
2 | #define __NET_NETLINK_H | |
3 | ||
4 | #include <linux/types.h> | |
5 | #include <linux/netlink.h> | |
6 | #include <linux/jiffies.h> | |
7 | #include <linux/in6.h> | |
8 | ||
9 | /* ======================================================================== | |
10 | * Netlink Messages and Attributes Interface (As Seen On TV) | |
11 | * ------------------------------------------------------------------------ | |
12 | * Messages Interface | |
13 | * ------------------------------------------------------------------------ | |
14 | * | |
15 | * Message Format: | |
16 | * <--- nlmsg_total_size(payload) ---> | |
17 | * <-- nlmsg_msg_size(payload) -> | |
18 | * +----------+- - -+-------------+- - -+-------- - - | |
19 | * | nlmsghdr | Pad | Payload | Pad | nlmsghdr | |
20 | * +----------+- - -+-------------+- - -+-------- - - | |
21 | * nlmsg_data(nlh)---^ ^ | |
22 | * nlmsg_next(nlh)-----------------------+ | |
23 | * | |
24 | * Payload Format: | |
25 | * <---------------------- nlmsg_len(nlh) ---------------------> | |
26 | * <------ hdrlen ------> <- nlmsg_attrlen(nlh, hdrlen) -> | |
27 | * +----------------------+- - -+--------------------------------+ | |
28 | * | Family Header | Pad | Attributes | | |
29 | * +----------------------+- - -+--------------------------------+ | |
30 | * nlmsg_attrdata(nlh, hdrlen)---^ | |
31 | * | |
32 | * Data Structures: | |
33 | * struct nlmsghdr netlink message header | |
34 | * | |
35 | * Message Construction: | |
36 | * nlmsg_new() create a new netlink message | |
37 | * nlmsg_put() add a netlink message to an skb | |
38 | * nlmsg_put_answer() callback based nlmsg_put() | |
39 | * nlmsg_end() finalize netlink message | |
40 | * nlmsg_get_pos() return current position in message | |
41 | * nlmsg_trim() trim part of message | |
42 | * nlmsg_cancel() cancel message construction | |
43 | * nlmsg_free() free a netlink message | |
44 | * | |
45 | * Message Sending: | |
46 | * nlmsg_multicast() multicast message to several groups | |
47 | * nlmsg_unicast() unicast a message to a single socket | |
48 | * nlmsg_notify() send notification message | |
49 | * | |
50 | * Message Length Calculations: | |
51 | * nlmsg_msg_size(payload) length of message w/o padding | |
52 | * nlmsg_total_size(payload) length of message w/ padding | |
53 | * nlmsg_padlen(payload) length of padding at tail | |
54 | * | |
55 | * Message Payload Access: | |
56 | * nlmsg_data(nlh) head of message payload | |
57 | * nlmsg_len(nlh) length of message payload | |
58 | * nlmsg_attrdata(nlh, hdrlen) head of attributes data | |
59 | * nlmsg_attrlen(nlh, hdrlen) length of attributes data | |
60 | * | |
61 | * Message Parsing: | |
62 | * nlmsg_ok(nlh, remaining) does nlh fit into remaining bytes? | |
63 | * nlmsg_next(nlh, remaining) get next netlink message | |
64 | * nlmsg_parse() parse attributes of a message | |
65 | * nlmsg_find_attr() find an attribute in a message | |
66 | * nlmsg_for_each_msg() loop over all messages | |
67 | * nlmsg_validate() validate netlink message incl. attrs | |
68 | * nlmsg_for_each_attr() loop over all attributes | |
69 | * | |
70 | * Misc: | |
71 | * nlmsg_report() report back to application? | |
72 | * | |
73 | * ------------------------------------------------------------------------ | |
74 | * Attributes Interface | |
75 | * ------------------------------------------------------------------------ | |
76 | * | |
77 | * Attribute Format: | |
78 | * <------- nla_total_size(payload) -------> | |
79 | * <---- nla_attr_size(payload) -----> | |
80 | * +----------+- - -+- - - - - - - - - +- - -+-------- - - | |
81 | * | Header | Pad | Payload | Pad | Header | |
82 | * +----------+- - -+- - - - - - - - - +- - -+-------- - - | |
83 | * <- nla_len(nla) -> ^ | |
84 | * nla_data(nla)----^ | | |
85 | * nla_next(nla)-----------------------------' | |
86 | * | |
87 | * Data Structures: | |
88 | * struct nlattr netlink attribute header | |
89 | * | |
90 | * Attribute Construction: | |
91 | * nla_reserve(skb, type, len) reserve room for an attribute | |
92 | * nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr | |
93 | * nla_put(skb, type, len, data) add attribute to skb | |
94 | * nla_put_nohdr(skb, len, data) add attribute w/o hdr | |
95 | * nla_append(skb, len, data) append data to skb | |
96 | * | |
97 | * Attribute Construction for Basic Types: | |
98 | * nla_put_u8(skb, type, value) add u8 attribute to skb | |
99 | * nla_put_u16(skb, type, value) add u16 attribute to skb | |
100 | * nla_put_u32(skb, type, value) add u32 attribute to skb | |
101 | * nla_put_u64_64bits(skb, type, | |
102 | * value, padattr) add u64 attribute to skb | |
103 | * nla_put_s8(skb, type, value) add s8 attribute to skb | |
104 | * nla_put_s16(skb, type, value) add s16 attribute to skb | |
105 | * nla_put_s32(skb, type, value) add s32 attribute to skb | |
106 | * nla_put_s64(skb, type, value, | |
107 | * padattr) add s64 attribute to skb | |
108 | * nla_put_string(skb, type, str) add string attribute to skb | |
109 | * nla_put_flag(skb, type) add flag attribute to skb | |
110 | * nla_put_msecs(skb, type, jiffies, | |
111 | * padattr) add msecs attribute to skb | |
112 | * nla_put_in_addr(skb, type, addr) add IPv4 address attribute to skb | |
113 | * nla_put_in6_addr(skb, type, addr) add IPv6 address attribute to skb | |
114 | * | |
115 | * Nested Attributes Construction: | |
116 | * nla_nest_start(skb, type) start a nested attribute | |
117 | * nla_nest_end(skb, nla) finalize a nested attribute | |
118 | * nla_nest_cancel(skb, nla) cancel nested attribute construction | |
119 | * | |
120 | * Attribute Length Calculations: | |
121 | * nla_attr_size(payload) length of attribute w/o padding | |
122 | * nla_total_size(payload) length of attribute w/ padding | |
123 | * nla_padlen(payload) length of padding | |
124 | * | |
125 | * Attribute Payload Access: | |
126 | * nla_data(nla) head of attribute payload | |
127 | * nla_len(nla) length of attribute payload | |
128 | * | |
129 | * Attribute Payload Access for Basic Types: | |
130 | * nla_get_u8(nla) get payload for a u8 attribute | |
131 | * nla_get_u16(nla) get payload for a u16 attribute | |
132 | * nla_get_u32(nla) get payload for a u32 attribute | |
133 | * nla_get_u64(nla) get payload for a u64 attribute | |
134 | * nla_get_s8(nla) get payload for a s8 attribute | |
135 | * nla_get_s16(nla) get payload for a s16 attribute | |
136 | * nla_get_s32(nla) get payload for a s32 attribute | |
137 | * nla_get_s64(nla) get payload for a s64 attribute | |
138 | * nla_get_flag(nla) return 1 if flag is true | |
139 | * nla_get_msecs(nla) get payload for a msecs attribute | |
140 | * | |
141 | * Attribute Misc: | |
142 | * nla_memcpy(dest, nla, count) copy attribute into memory | |
143 | * nla_memcmp(nla, data, size) compare attribute with memory area | |
144 | * nla_strlcpy(dst, nla, size) copy attribute to a sized string | |
145 | * nla_strcmp(nla, str) compare attribute with string | |
146 | * | |
147 | * Attribute Parsing: | |
148 | * nla_ok(nla, remaining) does nla fit into remaining bytes? | |
149 | * nla_next(nla, remaining) get next netlink attribute | |
150 | * nla_validate() validate a stream of attributes | |
151 | * nla_validate_nested() validate a stream of nested attributes | |
152 | * nla_find() find attribute in stream of attributes | |
153 | * nla_find_nested() find attribute in nested attributes | |
154 | * nla_parse() parse and validate stream of attrs | |
155 | * nla_parse_nested() parse nested attribuets | |
156 | * nla_for_each_attr() loop over all attributes | |
157 | * nla_for_each_nested() loop over the nested attributes | |
158 | *========================================================================= | |
159 | */ | |
160 | ||
161 | /** | |
162 | * Standard attribute types to specify validation policy | |
163 | */ | |
164 | enum { | |
165 | NLA_UNSPEC, | |
166 | NLA_U8, | |
167 | NLA_U16, | |
168 | NLA_U32, | |
169 | NLA_U64, | |
170 | NLA_STRING, | |
171 | NLA_FLAG, | |
172 | NLA_MSECS, | |
173 | NLA_NESTED, | |
174 | NLA_NESTED_COMPAT, | |
175 | NLA_NUL_STRING, | |
176 | NLA_BINARY, | |
177 | NLA_S8, | |
178 | NLA_S16, | |
179 | NLA_S32, | |
180 | NLA_S64, | |
181 | __NLA_TYPE_MAX, | |
182 | }; | |
183 | ||
184 | #define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1) | |
185 | ||
186 | /** | |
187 | * struct nla_policy - attribute validation policy | |
188 | * @type: Type of attribute or NLA_UNSPEC | |
189 | * @len: Type specific length of payload | |
190 | * | |
191 | * Policies are defined as arrays of this struct, the array must be | |
192 | * accessible by attribute type up to the highest identifier to be expected. | |
193 | * | |
194 | * Meaning of `len' field: | |
195 | * NLA_STRING Maximum length of string | |
196 | * NLA_NUL_STRING Maximum length of string (excluding NUL) | |
197 | * NLA_FLAG Unused | |
198 | * NLA_BINARY Maximum length of attribute payload | |
199 | * NLA_NESTED Don't use `len' field -- length verification is | |
200 | * done by checking len of nested header (or empty) | |
201 | * NLA_NESTED_COMPAT Minimum length of structure payload | |
202 | * NLA_U8, NLA_U16, | |
203 | * NLA_U32, NLA_U64, | |
204 | * NLA_S8, NLA_S16, | |
205 | * NLA_S32, NLA_S64, | |
206 | * NLA_MSECS Leaving the length field zero will verify the | |
207 | * given type fits, using it verifies minimum length | |
208 | * just like "All other" | |
209 | * All other Minimum length of attribute payload | |
210 | * | |
211 | * Example: | |
212 | * static const struct nla_policy my_policy[ATTR_MAX+1] = { | |
213 | * [ATTR_FOO] = { .type = NLA_U16 }, | |
214 | * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ }, | |
215 | * [ATTR_BAZ] = { .len = sizeof(struct mystruct) }, | |
216 | * }; | |
217 | */ | |
218 | struct nla_policy { | |
219 | u16 type; | |
220 | u16 len; | |
221 | }; | |
222 | ||
223 | /** | |
224 | * struct nl_info - netlink source information | |
225 | * @nlh: Netlink message header of original request | |
226 | * @portid: Netlink PORTID of requesting application | |
227 | */ | |
228 | struct nl_info { | |
229 | struct nlmsghdr *nlh; | |
230 | struct net *nl_net; | |
231 | u32 portid; | |
232 | bool skip_notify; | |
233 | }; | |
234 | ||
235 | int netlink_rcv_skb(struct sk_buff *skb, | |
236 | int (*cb)(struct sk_buff *, struct nlmsghdr *, | |
237 | struct netlink_ext_ack *)); | |
238 | int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid, | |
239 | unsigned int group, int report, gfp_t flags); | |
240 | ||
241 | int nla_validate(const struct nlattr *head, int len, int maxtype, | |
242 | const struct nla_policy *policy, | |
243 | struct netlink_ext_ack *extack); | |
244 | int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, | |
245 | int len, const struct nla_policy *policy, | |
246 | struct netlink_ext_ack *extack); | |
247 | int nla_policy_len(const struct nla_policy *, int); | |
248 | struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype); | |
249 | size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize); | |
250 | int nla_memcpy(void *dest, const struct nlattr *src, int count); | |
251 | int nla_memcmp(const struct nlattr *nla, const void *data, size_t size); | |
252 | int nla_strcmp(const struct nlattr *nla, const char *str); | |
253 | struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen); | |
254 | struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype, | |
255 | int attrlen, int padattr); | |
256 | void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen); | |
257 | struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen); | |
258 | struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype, | |
259 | int attrlen, int padattr); | |
260 | void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen); | |
261 | void __nla_put(struct sk_buff *skb, int attrtype, int attrlen, | |
262 | const void *data); | |
263 | void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen, | |
264 | const void *data, int padattr); | |
265 | void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data); | |
266 | int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data); | |
267 | int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen, | |
268 | const void *data, int padattr); | |
269 | int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data); | |
270 | int nla_append(struct sk_buff *skb, int attrlen, const void *data); | |
271 | ||
272 | /************************************************************************** | |
273 | * Netlink Messages | |
274 | **************************************************************************/ | |
275 | ||
276 | /** | |
277 | * nlmsg_msg_size - length of netlink message not including padding | |
278 | * @payload: length of message payload | |
279 | */ | |
280 | static inline int nlmsg_msg_size(int payload) | |
281 | { | |
282 | return NLMSG_HDRLEN + payload; | |
283 | } | |
284 | ||
285 | /** | |
286 | * nlmsg_total_size - length of netlink message including padding | |
287 | * @payload: length of message payload | |
288 | */ | |
289 | static inline int nlmsg_total_size(int payload) | |
290 | { | |
291 | return NLMSG_ALIGN(nlmsg_msg_size(payload)); | |
292 | } | |
293 | ||
294 | /** | |
295 | * nlmsg_padlen - length of padding at the message's tail | |
296 | * @payload: length of message payload | |
297 | */ | |
298 | static inline int nlmsg_padlen(int payload) | |
299 | { | |
300 | return nlmsg_total_size(payload) - nlmsg_msg_size(payload); | |
301 | } | |
302 | ||
303 | /** | |
304 | * nlmsg_data - head of message payload | |
305 | * @nlh: netlink message header | |
306 | */ | |
307 | static inline void *nlmsg_data(const struct nlmsghdr *nlh) | |
308 | { | |
309 | return (unsigned char *) nlh + NLMSG_HDRLEN; | |
310 | } | |
311 | ||
312 | /** | |
313 | * nlmsg_len - length of message payload | |
314 | * @nlh: netlink message header | |
315 | */ | |
316 | static inline int nlmsg_len(const struct nlmsghdr *nlh) | |
317 | { | |
318 | return nlh->nlmsg_len - NLMSG_HDRLEN; | |
319 | } | |
320 | ||
321 | /** | |
322 | * nlmsg_attrdata - head of attributes data | |
323 | * @nlh: netlink message header | |
324 | * @hdrlen: length of family specific header | |
325 | */ | |
326 | static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh, | |
327 | int hdrlen) | |
328 | { | |
329 | unsigned char *data = nlmsg_data(nlh); | |
330 | return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen)); | |
331 | } | |
332 | ||
333 | /** | |
334 | * nlmsg_attrlen - length of attributes data | |
335 | * @nlh: netlink message header | |
336 | * @hdrlen: length of family specific header | |
337 | */ | |
338 | static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen) | |
339 | { | |
340 | return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen); | |
341 | } | |
342 | ||
343 | /** | |
344 | * nlmsg_ok - check if the netlink message fits into the remaining bytes | |
345 | * @nlh: netlink message header | |
346 | * @remaining: number of bytes remaining in message stream | |
347 | */ | |
348 | static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining) | |
349 | { | |
350 | return (remaining >= (int) sizeof(struct nlmsghdr) && | |
351 | nlh->nlmsg_len >= sizeof(struct nlmsghdr) && | |
352 | nlh->nlmsg_len <= remaining); | |
353 | } | |
354 | ||
355 | /** | |
356 | * nlmsg_next - next netlink message in message stream | |
357 | * @nlh: netlink message header | |
358 | * @remaining: number of bytes remaining in message stream | |
359 | * | |
360 | * Returns the next netlink message in the message stream and | |
361 | * decrements remaining by the size of the current message. | |
362 | */ | |
363 | static inline struct nlmsghdr * | |
364 | nlmsg_next(const struct nlmsghdr *nlh, int *remaining) | |
365 | { | |
366 | int totlen = NLMSG_ALIGN(nlh->nlmsg_len); | |
367 | ||
368 | *remaining -= totlen; | |
369 | ||
370 | return (struct nlmsghdr *) ((unsigned char *) nlh + totlen); | |
371 | } | |
372 | ||
373 | /** | |
374 | * nlmsg_parse - parse attributes of a netlink message | |
375 | * @nlh: netlink message header | |
376 | * @hdrlen: length of family specific header | |
377 | * @tb: destination array with maxtype+1 elements | |
378 | * @maxtype: maximum attribute type to be expected | |
379 | * @policy: validation policy | |
380 | * @extack: extended ACK report struct | |
381 | * | |
382 | * See nla_parse() | |
383 | */ | |
384 | static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, | |
385 | struct nlattr *tb[], int maxtype, | |
386 | const struct nla_policy *policy, | |
387 | struct netlink_ext_ack *extack) | |
388 | { | |
389 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
390 | return -EINVAL; | |
391 | ||
392 | return nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen), | |
393 | nlmsg_attrlen(nlh, hdrlen), policy, extack); | |
394 | } | |
395 | ||
396 | /** | |
397 | * nlmsg_find_attr - find a specific attribute in a netlink message | |
398 | * @nlh: netlink message header | |
399 | * @hdrlen: length of familiy specific header | |
400 | * @attrtype: type of attribute to look for | |
401 | * | |
402 | * Returns the first attribute which matches the specified type. | |
403 | */ | |
404 | static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh, | |
405 | int hdrlen, int attrtype) | |
406 | { | |
407 | return nla_find(nlmsg_attrdata(nlh, hdrlen), | |
408 | nlmsg_attrlen(nlh, hdrlen), attrtype); | |
409 | } | |
410 | ||
411 | /** | |
412 | * nlmsg_validate - validate a netlink message including attributes | |
413 | * @nlh: netlinket message header | |
414 | * @hdrlen: length of familiy specific header | |
415 | * @maxtype: maximum attribute type to be expected | |
416 | * @policy: validation policy | |
417 | * @extack: extended ACK report struct | |
418 | */ | |
419 | static inline int nlmsg_validate(const struct nlmsghdr *nlh, | |
420 | int hdrlen, int maxtype, | |
421 | const struct nla_policy *policy, | |
422 | struct netlink_ext_ack *extack) | |
423 | { | |
424 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
425 | return -EINVAL; | |
426 | ||
427 | return nla_validate(nlmsg_attrdata(nlh, hdrlen), | |
428 | nlmsg_attrlen(nlh, hdrlen), maxtype, policy, | |
429 | extack); | |
430 | } | |
431 | ||
432 | /** | |
433 | * nlmsg_report - need to report back to application? | |
434 | * @nlh: netlink message header | |
435 | * | |
436 | * Returns 1 if a report back to the application is requested. | |
437 | */ | |
438 | static inline int nlmsg_report(const struct nlmsghdr *nlh) | |
439 | { | |
440 | return !!(nlh->nlmsg_flags & NLM_F_ECHO); | |
441 | } | |
442 | ||
443 | /** | |
444 | * nlmsg_for_each_attr - iterate over a stream of attributes | |
445 | * @pos: loop counter, set to current attribute | |
446 | * @nlh: netlink message header | |
447 | * @hdrlen: length of familiy specific header | |
448 | * @rem: initialized to len, holds bytes currently remaining in stream | |
449 | */ | |
450 | #define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \ | |
451 | nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \ | |
452 | nlmsg_attrlen(nlh, hdrlen), rem) | |
453 | ||
454 | /** | |
455 | * nlmsg_put - Add a new netlink message to an skb | |
456 | * @skb: socket buffer to store message in | |
457 | * @portid: netlink PORTID of requesting application | |
458 | * @seq: sequence number of message | |
459 | * @type: message type | |
460 | * @payload: length of message payload | |
461 | * @flags: message flags | |
462 | * | |
463 | * Returns NULL if the tailroom of the skb is insufficient to store | |
464 | * the message header and payload. | |
465 | */ | |
466 | static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, | |
467 | int type, int payload, int flags) | |
468 | { | |
469 | if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload))) | |
470 | return NULL; | |
471 | ||
472 | return __nlmsg_put(skb, portid, seq, type, payload, flags); | |
473 | } | |
474 | ||
475 | /** | |
476 | * nlmsg_put_answer - Add a new callback based netlink message to an skb | |
477 | * @skb: socket buffer to store message in | |
478 | * @cb: netlink callback | |
479 | * @type: message type | |
480 | * @payload: length of message payload | |
481 | * @flags: message flags | |
482 | * | |
483 | * Returns NULL if the tailroom of the skb is insufficient to store | |
484 | * the message header and payload. | |
485 | */ | |
486 | static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb, | |
487 | struct netlink_callback *cb, | |
488 | int type, int payload, | |
489 | int flags) | |
490 | { | |
491 | return nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, | |
492 | type, payload, flags); | |
493 | } | |
494 | ||
495 | /** | |
496 | * nlmsg_new - Allocate a new netlink message | |
497 | * @payload: size of the message payload | |
498 | * @flags: the type of memory to allocate. | |
499 | * | |
500 | * Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known | |
501 | * and a good default is needed. | |
502 | */ | |
503 | static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags) | |
504 | { | |
505 | return alloc_skb(nlmsg_total_size(payload), flags); | |
506 | } | |
507 | ||
508 | /** | |
509 | * nlmsg_end - Finalize a netlink message | |
510 | * @skb: socket buffer the message is stored in | |
511 | * @nlh: netlink message header | |
512 | * | |
513 | * Corrects the netlink message header to include the appeneded | |
514 | * attributes. Only necessary if attributes have been added to | |
515 | * the message. | |
516 | */ | |
517 | static inline void nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh) | |
518 | { | |
519 | nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh; | |
520 | } | |
521 | ||
522 | /** | |
523 | * nlmsg_get_pos - return current position in netlink message | |
524 | * @skb: socket buffer the message is stored in | |
525 | * | |
526 | * Returns a pointer to the current tail of the message. | |
527 | */ | |
528 | static inline void *nlmsg_get_pos(struct sk_buff *skb) | |
529 | { | |
530 | return skb_tail_pointer(skb); | |
531 | } | |
532 | ||
533 | /** | |
534 | * nlmsg_trim - Trim message to a mark | |
535 | * @skb: socket buffer the message is stored in | |
536 | * @mark: mark to trim to | |
537 | * | |
538 | * Trims the message to the provided mark. | |
539 | */ | |
540 | static inline void nlmsg_trim(struct sk_buff *skb, const void *mark) | |
541 | { | |
542 | if (mark) { | |
543 | WARN_ON((unsigned char *) mark < skb->data); | |
544 | skb_trim(skb, (unsigned char *) mark - skb->data); | |
545 | } | |
546 | } | |
547 | ||
548 | /** | |
549 | * nlmsg_cancel - Cancel construction of a netlink message | |
550 | * @skb: socket buffer the message is stored in | |
551 | * @nlh: netlink message header | |
552 | * | |
553 | * Removes the complete netlink message including all | |
554 | * attributes from the socket buffer again. | |
555 | */ | |
556 | static inline void nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh) | |
557 | { | |
558 | nlmsg_trim(skb, nlh); | |
559 | } | |
560 | ||
561 | /** | |
562 | * nlmsg_free - free a netlink message | |
563 | * @skb: socket buffer of netlink message | |
564 | */ | |
565 | static inline void nlmsg_free(struct sk_buff *skb) | |
566 | { | |
567 | kfree_skb(skb); | |
568 | } | |
569 | ||
570 | /** | |
571 | * nlmsg_multicast - multicast a netlink message | |
572 | * @sk: netlink socket to spread messages to | |
573 | * @skb: netlink message as socket buffer | |
574 | * @portid: own netlink portid to avoid sending to yourself | |
575 | * @group: multicast group id | |
576 | * @flags: allocation flags | |
577 | */ | |
578 | static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb, | |
579 | u32 portid, unsigned int group, gfp_t flags) | |
580 | { | |
581 | int err; | |
582 | ||
583 | NETLINK_CB(skb).dst_group = group; | |
584 | ||
585 | err = netlink_broadcast(sk, skb, portid, group, flags); | |
586 | if (err > 0) | |
587 | err = 0; | |
588 | ||
589 | return err; | |
590 | } | |
591 | ||
592 | /** | |
593 | * nlmsg_unicast - unicast a netlink message | |
594 | * @sk: netlink socket to spread message to | |
595 | * @skb: netlink message as socket buffer | |
596 | * @portid: netlink portid of the destination socket | |
597 | */ | |
598 | static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 portid) | |
599 | { | |
600 | int err; | |
601 | ||
602 | err = netlink_unicast(sk, skb, portid, MSG_DONTWAIT); | |
603 | if (err > 0) | |
604 | err = 0; | |
605 | ||
606 | return err; | |
607 | } | |
608 | ||
609 | /** | |
610 | * nlmsg_for_each_msg - iterate over a stream of messages | |
611 | * @pos: loop counter, set to current message | |
612 | * @head: head of message stream | |
613 | * @len: length of message stream | |
614 | * @rem: initialized to len, holds bytes currently remaining in stream | |
615 | */ | |
616 | #define nlmsg_for_each_msg(pos, head, len, rem) \ | |
617 | for (pos = head, rem = len; \ | |
618 | nlmsg_ok(pos, rem); \ | |
619 | pos = nlmsg_next(pos, &(rem))) | |
620 | ||
621 | /** | |
622 | * nl_dump_check_consistent - check if sequence is consistent and advertise if not | |
623 | * @cb: netlink callback structure that stores the sequence number | |
624 | * @nlh: netlink message header to write the flag to | |
625 | * | |
626 | * This function checks if the sequence (generation) number changed during dump | |
627 | * and if it did, advertises it in the netlink message header. | |
628 | * | |
629 | * The correct way to use it is to set cb->seq to the generation counter when | |
630 | * all locks for dumping have been acquired, and then call this function for | |
631 | * each message that is generated. | |
632 | * | |
633 | * Note that due to initialisation concerns, 0 is an invalid sequence number | |
634 | * and must not be used by code that uses this functionality. | |
635 | */ | |
636 | static inline void | |
637 | nl_dump_check_consistent(struct netlink_callback *cb, | |
638 | struct nlmsghdr *nlh) | |
639 | { | |
640 | if (cb->prev_seq && cb->seq != cb->prev_seq) | |
641 | nlh->nlmsg_flags |= NLM_F_DUMP_INTR; | |
642 | cb->prev_seq = cb->seq; | |
643 | } | |
644 | ||
645 | /************************************************************************** | |
646 | * Netlink Attributes | |
647 | **************************************************************************/ | |
648 | ||
649 | /** | |
650 | * nla_attr_size - length of attribute not including padding | |
651 | * @payload: length of payload | |
652 | */ | |
653 | static inline int nla_attr_size(int payload) | |
654 | { | |
655 | return NLA_HDRLEN + payload; | |
656 | } | |
657 | ||
658 | /** | |
659 | * nla_total_size - total length of attribute including padding | |
660 | * @payload: length of payload | |
661 | */ | |
662 | static inline int nla_total_size(int payload) | |
663 | { | |
664 | return NLA_ALIGN(nla_attr_size(payload)); | |
665 | } | |
666 | ||
667 | /** | |
668 | * nla_padlen - length of padding at the tail of attribute | |
669 | * @payload: length of payload | |
670 | */ | |
671 | static inline int nla_padlen(int payload) | |
672 | { | |
673 | return nla_total_size(payload) - nla_attr_size(payload); | |
674 | } | |
675 | ||
676 | /** | |
677 | * nla_type - attribute type | |
678 | * @nla: netlink attribute | |
679 | */ | |
680 | static inline int nla_type(const struct nlattr *nla) | |
681 | { | |
682 | return nla->nla_type & NLA_TYPE_MASK; | |
683 | } | |
684 | ||
685 | /** | |
686 | * nla_data - head of payload | |
687 | * @nla: netlink attribute | |
688 | */ | |
689 | static inline void *nla_data(const struct nlattr *nla) | |
690 | { | |
691 | return (char *) nla + NLA_HDRLEN; | |
692 | } | |
693 | ||
694 | /** | |
695 | * nla_len - length of payload | |
696 | * @nla: netlink attribute | |
697 | */ | |
698 | static inline int nla_len(const struct nlattr *nla) | |
699 | { | |
700 | return nla->nla_len - NLA_HDRLEN; | |
701 | } | |
702 | ||
703 | /** | |
704 | * nla_ok - check if the netlink attribute fits into the remaining bytes | |
705 | * @nla: netlink attribute | |
706 | * @remaining: number of bytes remaining in attribute stream | |
707 | */ | |
708 | static inline int nla_ok(const struct nlattr *nla, int remaining) | |
709 | { | |
710 | return remaining >= (int) sizeof(*nla) && | |
711 | nla->nla_len >= sizeof(*nla) && | |
712 | nla->nla_len <= remaining; | |
713 | } | |
714 | ||
715 | /** | |
716 | * nla_next - next netlink attribute in attribute stream | |
717 | * @nla: netlink attribute | |
718 | * @remaining: number of bytes remaining in attribute stream | |
719 | * | |
720 | * Returns the next netlink attribute in the attribute stream and | |
721 | * decrements remaining by the size of the current attribute. | |
722 | */ | |
723 | static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining) | |
724 | { | |
725 | unsigned int totlen = NLA_ALIGN(nla->nla_len); | |
726 | ||
727 | *remaining -= totlen; | |
728 | return (struct nlattr *) ((char *) nla + totlen); | |
729 | } | |
730 | ||
731 | /** | |
732 | * nla_find_nested - find attribute in a set of nested attributes | |
733 | * @nla: attribute containing the nested attributes | |
734 | * @attrtype: type of attribute to look for | |
735 | * | |
736 | * Returns the first attribute which matches the specified type. | |
737 | */ | |
738 | static inline struct nlattr * | |
739 | nla_find_nested(const struct nlattr *nla, int attrtype) | |
740 | { | |
741 | return nla_find(nla_data(nla), nla_len(nla), attrtype); | |
742 | } | |
743 | ||
744 | /** | |
745 | * nla_parse_nested - parse nested attributes | |
746 | * @tb: destination array with maxtype+1 elements | |
747 | * @maxtype: maximum attribute type to be expected | |
748 | * @nla: attribute containing the nested attributes | |
749 | * @policy: validation policy | |
750 | * @extack: extended ACK report struct | |
751 | * | |
752 | * See nla_parse() | |
753 | */ | |
754 | static inline int nla_parse_nested(struct nlattr *tb[], int maxtype, | |
755 | const struct nlattr *nla, | |
756 | const struct nla_policy *policy, | |
757 | struct netlink_ext_ack *extack) | |
758 | { | |
759 | return nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy, | |
760 | extack); | |
761 | } | |
762 | ||
763 | /** | |
764 | * nla_put_u8 - Add a u8 netlink attribute to a socket buffer | |
765 | * @skb: socket buffer to add attribute to | |
766 | * @attrtype: attribute type | |
767 | * @value: numeric value | |
768 | */ | |
769 | static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value) | |
770 | { | |
771 | return nla_put(skb, attrtype, sizeof(u8), &value); | |
772 | } | |
773 | ||
774 | /** | |
775 | * nla_put_u16 - Add a u16 netlink attribute to a socket buffer | |
776 | * @skb: socket buffer to add attribute to | |
777 | * @attrtype: attribute type | |
778 | * @value: numeric value | |
779 | */ | |
780 | static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value) | |
781 | { | |
782 | return nla_put(skb, attrtype, sizeof(u16), &value); | |
783 | } | |
784 | ||
785 | /** | |
786 | * nla_put_be16 - Add a __be16 netlink attribute to a socket buffer | |
787 | * @skb: socket buffer to add attribute to | |
788 | * @attrtype: attribute type | |
789 | * @value: numeric value | |
790 | */ | |
791 | static inline int nla_put_be16(struct sk_buff *skb, int attrtype, __be16 value) | |
792 | { | |
793 | return nla_put(skb, attrtype, sizeof(__be16), &value); | |
794 | } | |
795 | ||
796 | /** | |
797 | * nla_put_net16 - Add 16-bit network byte order netlink attribute to a socket buffer | |
798 | * @skb: socket buffer to add attribute to | |
799 | * @attrtype: attribute type | |
800 | * @value: numeric value | |
801 | */ | |
802 | static inline int nla_put_net16(struct sk_buff *skb, int attrtype, __be16 value) | |
803 | { | |
804 | return nla_put_be16(skb, attrtype | NLA_F_NET_BYTEORDER, value); | |
805 | } | |
806 | ||
807 | /** | |
808 | * nla_put_le16 - Add a __le16 netlink attribute to a socket buffer | |
809 | * @skb: socket buffer to add attribute to | |
810 | * @attrtype: attribute type | |
811 | * @value: numeric value | |
812 | */ | |
813 | static inline int nla_put_le16(struct sk_buff *skb, int attrtype, __le16 value) | |
814 | { | |
815 | return nla_put(skb, attrtype, sizeof(__le16), &value); | |
816 | } | |
817 | ||
818 | /** | |
819 | * nla_put_u32 - Add a u32 netlink attribute to a socket buffer | |
820 | * @skb: socket buffer to add attribute to | |
821 | * @attrtype: attribute type | |
822 | * @value: numeric value | |
823 | */ | |
824 | static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value) | |
825 | { | |
826 | return nla_put(skb, attrtype, sizeof(u32), &value); | |
827 | } | |
828 | ||
829 | /** | |
830 | * nla_put_be32 - Add a __be32 netlink attribute to a socket buffer | |
831 | * @skb: socket buffer to add attribute to | |
832 | * @attrtype: attribute type | |
833 | * @value: numeric value | |
834 | */ | |
835 | static inline int nla_put_be32(struct sk_buff *skb, int attrtype, __be32 value) | |
836 | { | |
837 | return nla_put(skb, attrtype, sizeof(__be32), &value); | |
838 | } | |
839 | ||
840 | /** | |
841 | * nla_put_net32 - Add 32-bit network byte order netlink attribute to a socket buffer | |
842 | * @skb: socket buffer to add attribute to | |
843 | * @attrtype: attribute type | |
844 | * @value: numeric value | |
845 | */ | |
846 | static inline int nla_put_net32(struct sk_buff *skb, int attrtype, __be32 value) | |
847 | { | |
848 | return nla_put_be32(skb, attrtype | NLA_F_NET_BYTEORDER, value); | |
849 | } | |
850 | ||
851 | /** | |
852 | * nla_put_le32 - Add a __le32 netlink attribute to a socket buffer | |
853 | * @skb: socket buffer to add attribute to | |
854 | * @attrtype: attribute type | |
855 | * @value: numeric value | |
856 | */ | |
857 | static inline int nla_put_le32(struct sk_buff *skb, int attrtype, __le32 value) | |
858 | { | |
859 | return nla_put(skb, attrtype, sizeof(__le32), &value); | |
860 | } | |
861 | ||
862 | /** | |
863 | * nla_put_u64_64bit - Add a u64 netlink attribute to a skb and align it | |
864 | * @skb: socket buffer to add attribute to | |
865 | * @attrtype: attribute type | |
866 | * @value: numeric value | |
867 | * @padattr: attribute type for the padding | |
868 | */ | |
869 | static inline int nla_put_u64_64bit(struct sk_buff *skb, int attrtype, | |
870 | u64 value, int padattr) | |
871 | { | |
872 | return nla_put_64bit(skb, attrtype, sizeof(u64), &value, padattr); | |
873 | } | |
874 | ||
875 | /** | |
876 | * nla_put_be64 - Add a __be64 netlink attribute to a socket buffer and align it | |
877 | * @skb: socket buffer to add attribute to | |
878 | * @attrtype: attribute type | |
879 | * @value: numeric value | |
880 | * @padattr: attribute type for the padding | |
881 | */ | |
882 | static inline int nla_put_be64(struct sk_buff *skb, int attrtype, __be64 value, | |
883 | int padattr) | |
884 | { | |
885 | return nla_put_64bit(skb, attrtype, sizeof(__be64), &value, padattr); | |
886 | } | |
887 | ||
888 | /** | |
889 | * nla_put_net64 - Add 64-bit network byte order nlattr to a skb and align it | |
890 | * @skb: socket buffer to add attribute to | |
891 | * @attrtype: attribute type | |
892 | * @value: numeric value | |
893 | * @padattr: attribute type for the padding | |
894 | */ | |
895 | static inline int nla_put_net64(struct sk_buff *skb, int attrtype, __be64 value, | |
896 | int padattr) | |
897 | { | |
898 | return nla_put_be64(skb, attrtype | NLA_F_NET_BYTEORDER, value, | |
899 | padattr); | |
900 | } | |
901 | ||
902 | /** | |
903 | * nla_put_le64 - Add a __le64 netlink attribute to a socket buffer and align it | |
904 | * @skb: socket buffer to add attribute to | |
905 | * @attrtype: attribute type | |
906 | * @value: numeric value | |
907 | * @padattr: attribute type for the padding | |
908 | */ | |
909 | static inline int nla_put_le64(struct sk_buff *skb, int attrtype, __le64 value, | |
910 | int padattr) | |
911 | { | |
912 | return nla_put_64bit(skb, attrtype, sizeof(__le64), &value, padattr); | |
913 | } | |
914 | ||
915 | /** | |
916 | * nla_put_s8 - Add a s8 netlink attribute to a socket buffer | |
917 | * @skb: socket buffer to add attribute to | |
918 | * @attrtype: attribute type | |
919 | * @value: numeric value | |
920 | */ | |
921 | static inline int nla_put_s8(struct sk_buff *skb, int attrtype, s8 value) | |
922 | { | |
923 | return nla_put(skb, attrtype, sizeof(s8), &value); | |
924 | } | |
925 | ||
926 | /** | |
927 | * nla_put_s16 - Add a s16 netlink attribute to a socket buffer | |
928 | * @skb: socket buffer to add attribute to | |
929 | * @attrtype: attribute type | |
930 | * @value: numeric value | |
931 | */ | |
932 | static inline int nla_put_s16(struct sk_buff *skb, int attrtype, s16 value) | |
933 | { | |
934 | return nla_put(skb, attrtype, sizeof(s16), &value); | |
935 | } | |
936 | ||
937 | /** | |
938 | * nla_put_s32 - Add a s32 netlink attribute to a socket buffer | |
939 | * @skb: socket buffer to add attribute to | |
940 | * @attrtype: attribute type | |
941 | * @value: numeric value | |
942 | */ | |
943 | static inline int nla_put_s32(struct sk_buff *skb, int attrtype, s32 value) | |
944 | { | |
945 | return nla_put(skb, attrtype, sizeof(s32), &value); | |
946 | } | |
947 | ||
948 | /** | |
949 | * nla_put_s64 - Add a s64 netlink attribute to a socket buffer and align it | |
950 | * @skb: socket buffer to add attribute to | |
951 | * @attrtype: attribute type | |
952 | * @value: numeric value | |
953 | * @padattr: attribute type for the padding | |
954 | */ | |
955 | static inline int nla_put_s64(struct sk_buff *skb, int attrtype, s64 value, | |
956 | int padattr) | |
957 | { | |
958 | return nla_put_64bit(skb, attrtype, sizeof(s64), &value, padattr); | |
959 | } | |
960 | ||
961 | /** | |
962 | * nla_put_string - Add a string netlink attribute to a socket buffer | |
963 | * @skb: socket buffer to add attribute to | |
964 | * @attrtype: attribute type | |
965 | * @str: NUL terminated string | |
966 | */ | |
967 | static inline int nla_put_string(struct sk_buff *skb, int attrtype, | |
968 | const char *str) | |
969 | { | |
970 | return nla_put(skb, attrtype, strlen(str) + 1, str); | |
971 | } | |
972 | ||
973 | /** | |
974 | * nla_put_flag - Add a flag netlink attribute to a socket buffer | |
975 | * @skb: socket buffer to add attribute to | |
976 | * @attrtype: attribute type | |
977 | */ | |
978 | static inline int nla_put_flag(struct sk_buff *skb, int attrtype) | |
979 | { | |
980 | return nla_put(skb, attrtype, 0, NULL); | |
981 | } | |
982 | ||
983 | /** | |
984 | * nla_put_msecs - Add a msecs netlink attribute to a skb and align it | |
985 | * @skb: socket buffer to add attribute to | |
986 | * @attrtype: attribute type | |
987 | * @njiffies: number of jiffies to convert to msecs | |
988 | * @padattr: attribute type for the padding | |
989 | */ | |
990 | static inline int nla_put_msecs(struct sk_buff *skb, int attrtype, | |
991 | unsigned long njiffies, int padattr) | |
992 | { | |
993 | u64 tmp = jiffies_to_msecs(njiffies); | |
994 | ||
995 | return nla_put_64bit(skb, attrtype, sizeof(u64), &tmp, padattr); | |
996 | } | |
997 | ||
998 | /** | |
999 | * nla_put_in_addr - Add an IPv4 address netlink attribute to a socket | |
1000 | * buffer | |
1001 | * @skb: socket buffer to add attribute to | |
1002 | * @attrtype: attribute type | |
1003 | * @addr: IPv4 address | |
1004 | */ | |
1005 | static inline int nla_put_in_addr(struct sk_buff *skb, int attrtype, | |
1006 | __be32 addr) | |
1007 | { | |
1008 | return nla_put_be32(skb, attrtype, addr); | |
1009 | } | |
1010 | ||
1011 | /** | |
1012 | * nla_put_in6_addr - Add an IPv6 address netlink attribute to a socket | |
1013 | * buffer | |
1014 | * @skb: socket buffer to add attribute to | |
1015 | * @attrtype: attribute type | |
1016 | * @addr: IPv6 address | |
1017 | */ | |
1018 | static inline int nla_put_in6_addr(struct sk_buff *skb, int attrtype, | |
1019 | const struct in6_addr *addr) | |
1020 | { | |
1021 | return nla_put(skb, attrtype, sizeof(*addr), addr); | |
1022 | } | |
1023 | ||
1024 | /** | |
1025 | * nla_get_u32 - return payload of u32 attribute | |
1026 | * @nla: u32 netlink attribute | |
1027 | */ | |
1028 | static inline u32 nla_get_u32(const struct nlattr *nla) | |
1029 | { | |
1030 | return *(u32 *) nla_data(nla); | |
1031 | } | |
1032 | ||
1033 | /** | |
1034 | * nla_get_be32 - return payload of __be32 attribute | |
1035 | * @nla: __be32 netlink attribute | |
1036 | */ | |
1037 | static inline __be32 nla_get_be32(const struct nlattr *nla) | |
1038 | { | |
1039 | return *(__be32 *) nla_data(nla); | |
1040 | } | |
1041 | ||
1042 | /** | |
1043 | * nla_get_le32 - return payload of __le32 attribute | |
1044 | * @nla: __le32 netlink attribute | |
1045 | */ | |
1046 | static inline __le32 nla_get_le32(const struct nlattr *nla) | |
1047 | { | |
1048 | return *(__le32 *) nla_data(nla); | |
1049 | } | |
1050 | ||
1051 | /** | |
1052 | * nla_get_u16 - return payload of u16 attribute | |
1053 | * @nla: u16 netlink attribute | |
1054 | */ | |
1055 | static inline u16 nla_get_u16(const struct nlattr *nla) | |
1056 | { | |
1057 | return *(u16 *) nla_data(nla); | |
1058 | } | |
1059 | ||
1060 | /** | |
1061 | * nla_get_be16 - return payload of __be16 attribute | |
1062 | * @nla: __be16 netlink attribute | |
1063 | */ | |
1064 | static inline __be16 nla_get_be16(const struct nlattr *nla) | |
1065 | { | |
1066 | return *(__be16 *) nla_data(nla); | |
1067 | } | |
1068 | ||
1069 | /** | |
1070 | * nla_get_le16 - return payload of __le16 attribute | |
1071 | * @nla: __le16 netlink attribute | |
1072 | */ | |
1073 | static inline __le16 nla_get_le16(const struct nlattr *nla) | |
1074 | { | |
1075 | return *(__le16 *) nla_data(nla); | |
1076 | } | |
1077 | ||
1078 | /** | |
1079 | * nla_get_u8 - return payload of u8 attribute | |
1080 | * @nla: u8 netlink attribute | |
1081 | */ | |
1082 | static inline u8 nla_get_u8(const struct nlattr *nla) | |
1083 | { | |
1084 | return *(u8 *) nla_data(nla); | |
1085 | } | |
1086 | ||
1087 | /** | |
1088 | * nla_get_u64 - return payload of u64 attribute | |
1089 | * @nla: u64 netlink attribute | |
1090 | */ | |
1091 | static inline u64 nla_get_u64(const struct nlattr *nla) | |
1092 | { | |
1093 | u64 tmp; | |
1094 | ||
1095 | nla_memcpy(&tmp, nla, sizeof(tmp)); | |
1096 | ||
1097 | return tmp; | |
1098 | } | |
1099 | ||
1100 | /** | |
1101 | * nla_get_be64 - return payload of __be64 attribute | |
1102 | * @nla: __be64 netlink attribute | |
1103 | */ | |
1104 | static inline __be64 nla_get_be64(const struct nlattr *nla) | |
1105 | { | |
1106 | __be64 tmp; | |
1107 | ||
1108 | nla_memcpy(&tmp, nla, sizeof(tmp)); | |
1109 | ||
1110 | return tmp; | |
1111 | } | |
1112 | ||
1113 | /** | |
1114 | * nla_get_le64 - return payload of __le64 attribute | |
1115 | * @nla: __le64 netlink attribute | |
1116 | */ | |
1117 | static inline __le64 nla_get_le64(const struct nlattr *nla) | |
1118 | { | |
1119 | return *(__le64 *) nla_data(nla); | |
1120 | } | |
1121 | ||
1122 | /** | |
1123 | * nla_get_s32 - return payload of s32 attribute | |
1124 | * @nla: s32 netlink attribute | |
1125 | */ | |
1126 | static inline s32 nla_get_s32(const struct nlattr *nla) | |
1127 | { | |
1128 | return *(s32 *) nla_data(nla); | |
1129 | } | |
1130 | ||
1131 | /** | |
1132 | * nla_get_s16 - return payload of s16 attribute | |
1133 | * @nla: s16 netlink attribute | |
1134 | */ | |
1135 | static inline s16 nla_get_s16(const struct nlattr *nla) | |
1136 | { | |
1137 | return *(s16 *) nla_data(nla); | |
1138 | } | |
1139 | ||
1140 | /** | |
1141 | * nla_get_s8 - return payload of s8 attribute | |
1142 | * @nla: s8 netlink attribute | |
1143 | */ | |
1144 | static inline s8 nla_get_s8(const struct nlattr *nla) | |
1145 | { | |
1146 | return *(s8 *) nla_data(nla); | |
1147 | } | |
1148 | ||
1149 | /** | |
1150 | * nla_get_s64 - return payload of s64 attribute | |
1151 | * @nla: s64 netlink attribute | |
1152 | */ | |
1153 | static inline s64 nla_get_s64(const struct nlattr *nla) | |
1154 | { | |
1155 | s64 tmp; | |
1156 | ||
1157 | nla_memcpy(&tmp, nla, sizeof(tmp)); | |
1158 | ||
1159 | return tmp; | |
1160 | } | |
1161 | ||
1162 | /** | |
1163 | * nla_get_flag - return payload of flag attribute | |
1164 | * @nla: flag netlink attribute | |
1165 | */ | |
1166 | static inline int nla_get_flag(const struct nlattr *nla) | |
1167 | { | |
1168 | return !!nla; | |
1169 | } | |
1170 | ||
1171 | /** | |
1172 | * nla_get_msecs - return payload of msecs attribute | |
1173 | * @nla: msecs netlink attribute | |
1174 | * | |
1175 | * Returns the number of milliseconds in jiffies. | |
1176 | */ | |
1177 | static inline unsigned long nla_get_msecs(const struct nlattr *nla) | |
1178 | { | |
1179 | u64 msecs = nla_get_u64(nla); | |
1180 | ||
1181 | return msecs_to_jiffies((unsigned long) msecs); | |
1182 | } | |
1183 | ||
1184 | /** | |
1185 | * nla_get_in_addr - return payload of IPv4 address attribute | |
1186 | * @nla: IPv4 address netlink attribute | |
1187 | */ | |
1188 | static inline __be32 nla_get_in_addr(const struct nlattr *nla) | |
1189 | { | |
1190 | return *(__be32 *) nla_data(nla); | |
1191 | } | |
1192 | ||
1193 | /** | |
1194 | * nla_get_in6_addr - return payload of IPv6 address attribute | |
1195 | * @nla: IPv6 address netlink attribute | |
1196 | */ | |
1197 | static inline struct in6_addr nla_get_in6_addr(const struct nlattr *nla) | |
1198 | { | |
1199 | struct in6_addr tmp; | |
1200 | ||
1201 | nla_memcpy(&tmp, nla, sizeof(tmp)); | |
1202 | return tmp; | |
1203 | } | |
1204 | ||
1205 | /** | |
1206 | * nla_memdup - duplicate attribute memory (kmemdup) | |
1207 | * @src: netlink attribute to duplicate from | |
1208 | * @gfp: GFP mask | |
1209 | */ | |
1210 | static inline void *nla_memdup(const struct nlattr *src, gfp_t gfp) | |
1211 | { | |
1212 | return kmemdup(nla_data(src), nla_len(src), gfp); | |
1213 | } | |
1214 | ||
1215 | /** | |
1216 | * nla_nest_start - Start a new level of nested attributes | |
1217 | * @skb: socket buffer to add attributes to | |
1218 | * @attrtype: attribute type of container | |
1219 | * | |
1220 | * Returns the container attribute | |
1221 | */ | |
1222 | static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype) | |
1223 | { | |
1224 | struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb); | |
1225 | ||
1226 | if (nla_put(skb, attrtype, 0, NULL) < 0) | |
1227 | return NULL; | |
1228 | ||
1229 | return start; | |
1230 | } | |
1231 | ||
1232 | /** | |
1233 | * nla_nest_end - Finalize nesting of attributes | |
1234 | * @skb: socket buffer the attributes are stored in | |
1235 | * @start: container attribute | |
1236 | * | |
1237 | * Corrects the container attribute header to include the all | |
1238 | * appeneded attributes. | |
1239 | * | |
1240 | * Returns the total data length of the skb. | |
1241 | */ | |
1242 | static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start) | |
1243 | { | |
1244 | start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start; | |
1245 | return skb->len; | |
1246 | } | |
1247 | ||
1248 | /** | |
1249 | * nla_nest_cancel - Cancel nesting of attributes | |
1250 | * @skb: socket buffer the message is stored in | |
1251 | * @start: container attribute | |
1252 | * | |
1253 | * Removes the container attribute and including all nested | |
1254 | * attributes. Returns -EMSGSIZE | |
1255 | */ | |
1256 | static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) | |
1257 | { | |
1258 | nlmsg_trim(skb, start); | |
1259 | } | |
1260 | ||
1261 | /** | |
1262 | * nla_validate_nested - Validate a stream of nested attributes | |
1263 | * @start: container attribute | |
1264 | * @maxtype: maximum attribute type to be expected | |
1265 | * @policy: validation policy | |
1266 | * @extack: extended ACK report struct | |
1267 | * | |
1268 | * Validates all attributes in the nested attribute stream against the | |
1269 | * specified policy. Attributes with a type exceeding maxtype will be | |
1270 | * ignored. See documenation of struct nla_policy for more details. | |
1271 | * | |
1272 | * Returns 0 on success or a negative error code. | |
1273 | */ | |
1274 | static inline int nla_validate_nested(const struct nlattr *start, int maxtype, | |
1275 | const struct nla_policy *policy, | |
1276 | struct netlink_ext_ack *extack) | |
1277 | { | |
1278 | return nla_validate(nla_data(start), nla_len(start), maxtype, policy, | |
1279 | extack); | |
1280 | } | |
1281 | ||
1282 | /** | |
1283 | * nla_need_padding_for_64bit - test 64-bit alignment of the next attribute | |
1284 | * @skb: socket buffer the message is stored in | |
1285 | * | |
1286 | * Return true if padding is needed to align the next attribute (nla_data()) to | |
1287 | * a 64-bit aligned area. | |
1288 | */ | |
1289 | static inline bool nla_need_padding_for_64bit(struct sk_buff *skb) | |
1290 | { | |
1291 | #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS | |
1292 | /* The nlattr header is 4 bytes in size, that's why we test | |
1293 | * if the skb->data _is_ aligned. A NOP attribute, plus | |
1294 | * nlattr header for next attribute, will make nla_data() | |
1295 | * 8-byte aligned. | |
1296 | */ | |
1297 | if (IS_ALIGNED((unsigned long)skb_tail_pointer(skb), 8)) | |
1298 | return true; | |
1299 | #endif | |
1300 | return false; | |
1301 | } | |
1302 | ||
1303 | /** | |
1304 | * nla_align_64bit - 64-bit align the nla_data() of next attribute | |
1305 | * @skb: socket buffer the message is stored in | |
1306 | * @padattr: attribute type for the padding | |
1307 | * | |
1308 | * Conditionally emit a padding netlink attribute in order to make | |
1309 | * the next attribute we emit have a 64-bit aligned nla_data() area. | |
1310 | * This will only be done in architectures which do not have | |
1311 | * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS defined. | |
1312 | * | |
1313 | * Returns zero on success or a negative error code. | |
1314 | */ | |
1315 | static inline int nla_align_64bit(struct sk_buff *skb, int padattr) | |
1316 | { | |
1317 | if (nla_need_padding_for_64bit(skb) && | |
1318 | !nla_reserve(skb, padattr, 0)) | |
1319 | return -EMSGSIZE; | |
1320 | ||
1321 | return 0; | |
1322 | } | |
1323 | ||
1324 | /** | |
1325 | * nla_total_size_64bit - total length of attribute including padding | |
1326 | * @payload: length of payload | |
1327 | */ | |
1328 | static inline int nla_total_size_64bit(int payload) | |
1329 | { | |
1330 | return NLA_ALIGN(nla_attr_size(payload)) | |
1331 | #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS | |
1332 | + NLA_ALIGN(nla_attr_size(0)) | |
1333 | #endif | |
1334 | ; | |
1335 | } | |
1336 | ||
1337 | /** | |
1338 | * nla_for_each_attr - iterate over a stream of attributes | |
1339 | * @pos: loop counter, set to current attribute | |
1340 | * @head: head of attribute stream | |
1341 | * @len: length of attribute stream | |
1342 | * @rem: initialized to len, holds bytes currently remaining in stream | |
1343 | */ | |
1344 | #define nla_for_each_attr(pos, head, len, rem) \ | |
1345 | for (pos = head, rem = len; \ | |
1346 | nla_ok(pos, rem); \ | |
1347 | pos = nla_next(pos, &(rem))) | |
1348 | ||
1349 | /** | |
1350 | * nla_for_each_nested - iterate over nested attributes | |
1351 | * @pos: loop counter, set to current attribute | |
1352 | * @nla: attribute containing the nested attributes | |
1353 | * @rem: initialized to len, holds bytes currently remaining in stream | |
1354 | */ | |
1355 | #define nla_for_each_nested(pos, nla, rem) \ | |
1356 | nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem) | |
1357 | ||
1358 | /** | |
1359 | * nla_is_last - Test if attribute is last in stream | |
1360 | * @nla: attribute to test | |
1361 | * @rem: bytes remaining in stream | |
1362 | */ | |
1363 | static inline bool nla_is_last(const struct nlattr *nla, int rem) | |
1364 | { | |
1365 | return nla->nla_len == rem; | |
1366 | } | |
1367 | ||
1368 | #endif |