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Diffstat (limited to 'include/net/netlink.h')
-rw-r--r-- | include/net/netlink.h | 883 |
1 files changed, 883 insertions, 0 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h new file mode 100644 index 000000000000..640c26a90cf1 --- /dev/null +++ b/include/net/netlink.h | |||
@@ -0,0 +1,883 @@ | |||
1 | #ifndef __NET_NETLINK_H | ||
2 | #define __NET_NETLINK_H | ||
3 | |||
4 | #include <linux/types.h> | ||
5 | #include <linux/netlink.h> | ||
6 | |||
7 | /* ======================================================================== | ||
8 | * Netlink Messages and Attributes Interface (As Seen On TV) | ||
9 | * ------------------------------------------------------------------------ | ||
10 | * Messages Interface | ||
11 | * ------------------------------------------------------------------------ | ||
12 | * | ||
13 | * Message Format: | ||
14 | * <--- nlmsg_total_size(payload) ---> | ||
15 | * <-- nlmsg_msg_size(payload) -> | ||
16 | * +----------+- - -+-------------+- - -+-------- - - | ||
17 | * | nlmsghdr | Pad | Payload | Pad | nlmsghdr | ||
18 | * +----------+- - -+-------------+- - -+-------- - - | ||
19 | * nlmsg_data(nlh)---^ ^ | ||
20 | * nlmsg_next(nlh)-----------------------+ | ||
21 | * | ||
22 | * Payload Format: | ||
23 | * <---------------------- nlmsg_len(nlh) ---------------------> | ||
24 | * <------ hdrlen ------> <- nlmsg_attrlen(nlh, hdrlen) -> | ||
25 | * +----------------------+- - -+--------------------------------+ | ||
26 | * | Family Header | Pad | Attributes | | ||
27 | * +----------------------+- - -+--------------------------------+ | ||
28 | * nlmsg_attrdata(nlh, hdrlen)---^ | ||
29 | * | ||
30 | * Data Structures: | ||
31 | * struct nlmsghdr netlink message header | ||
32 | * | ||
33 | * Message Construction: | ||
34 | * nlmsg_new() create a new netlink message | ||
35 | * nlmsg_put() add a netlink message to an skb | ||
36 | * nlmsg_put_answer() callback based nlmsg_put() | ||
37 | * nlmsg_end() finanlize netlink message | ||
38 | * nlmsg_cancel() cancel message construction | ||
39 | * nlmsg_free() free a netlink message | ||
40 | * | ||
41 | * Message Sending: | ||
42 | * nlmsg_multicast() multicast message to several groups | ||
43 | * nlmsg_unicast() unicast a message to a single socket | ||
44 | * | ||
45 | * Message Length Calculations: | ||
46 | * nlmsg_msg_size(payload) length of message w/o padding | ||
47 | * nlmsg_total_size(payload) length of message w/ padding | ||
48 | * nlmsg_padlen(payload) length of padding at tail | ||
49 | * | ||
50 | * Message Payload Access: | ||
51 | * nlmsg_data(nlh) head of message payload | ||
52 | * nlmsg_len(nlh) length of message payload | ||
53 | * nlmsg_attrdata(nlh, hdrlen) head of attributes data | ||
54 | * nlmsg_attrlen(nlh, hdrlen) length of attributes data | ||
55 | * | ||
56 | * Message Parsing: | ||
57 | * nlmsg_ok(nlh, remaining) does nlh fit into remaining bytes? | ||
58 | * nlmsg_next(nlh, remaining) get next netlink message | ||
59 | * nlmsg_parse() parse attributes of a message | ||
60 | * nlmsg_find_attr() find an attribute in a message | ||
61 | * nlmsg_for_each_msg() loop over all messages | ||
62 | * nlmsg_validate() validate netlink message incl. attrs | ||
63 | * nlmsg_for_each_attr() loop over all attributes | ||
64 | * | ||
65 | * ------------------------------------------------------------------------ | ||
66 | * Attributes Interface | ||
67 | * ------------------------------------------------------------------------ | ||
68 | * | ||
69 | * Attribute Format: | ||
70 | * <------- nla_total_size(payload) -------> | ||
71 | * <---- nla_attr_size(payload) -----> | ||
72 | * +----------+- - -+- - - - - - - - - +- - -+-------- - - | ||
73 | * | Header | Pad | Payload | Pad | Header | ||
74 | * +----------+- - -+- - - - - - - - - +- - -+-------- - - | ||
75 | * <- nla_len(nla) -> ^ | ||
76 | * nla_data(nla)----^ | | ||
77 | * nla_next(nla)-----------------------------' | ||
78 | * | ||
79 | * Data Structures: | ||
80 | * struct nlattr netlink attribtue header | ||
81 | * | ||
82 | * Attribute Construction: | ||
83 | * nla_reserve(skb, type, len) reserve skb tailroom for an attribute | ||
84 | * nla_put(skb, type, len, data) add attribute to skb | ||
85 | * | ||
86 | * Attribute Construction for Basic Types: | ||
87 | * nla_put_u8(skb, type, value) add u8 attribute to skb | ||
88 | * nla_put_u16(skb, type, value) add u16 attribute to skb | ||
89 | * nla_put_u32(skb, type, value) add u32 attribute to skb | ||
90 | * nla_put_u64(skb, type, value) add u64 attribute to skb | ||
91 | * nla_put_string(skb, type, str) add string attribute to skb | ||
92 | * nla_put_flag(skb, type) add flag attribute to skb | ||
93 | * nla_put_msecs(skb, type, jiffies) add msecs attribute to skb | ||
94 | * | ||
95 | * Exceptions Based Attribute Construction: | ||
96 | * NLA_PUT(skb, type, len, data) add attribute to skb | ||
97 | * NLA_PUT_U8(skb, type, value) add u8 attribute to skb | ||
98 | * NLA_PUT_U16(skb, type, value) add u16 attribute to skb | ||
99 | * NLA_PUT_U32(skb, type, value) add u32 attribute to skb | ||
100 | * NLA_PUT_U64(skb, type, value) add u64 attribute to skb | ||
101 | * NLA_PUT_STRING(skb, type, str) add string attribute to skb | ||
102 | * NLA_PUT_FLAG(skb, type) add flag attribute to skb | ||
103 | * NLA_PUT_MSECS(skb, type, jiffies) add msecs attribute to skb | ||
104 | * | ||
105 | * The meaning of these functions is equal to their lower case | ||
106 | * variants but they jump to the label nla_put_failure in case | ||
107 | * of a failure. | ||
108 | * | ||
109 | * Nested Attributes Construction: | ||
110 | * nla_nest_start(skb, type) start a nested attribute | ||
111 | * nla_nest_end(skb, nla) finalize a nested attribute | ||
112 | * nla_nest_cancel(skb, nla) cancel nested attribute construction | ||
113 | * | ||
114 | * Attribute Length Calculations: | ||
115 | * nla_attr_size(payload) length of attribute w/o padding | ||
116 | * nla_total_size(payload) length of attribute w/ padding | ||
117 | * nla_padlen(payload) length of padding | ||
118 | * | ||
119 | * Attribute Payload Access: | ||
120 | * nla_data(nla) head of attribute payload | ||
121 | * nla_len(nla) length of attribute payload | ||
122 | * | ||
123 | * Attribute Payload Access for Basic Types: | ||
124 | * nla_get_u8(nla) get payload for a u8 attribute | ||
125 | * nla_get_u16(nla) get payload for a u16 attribute | ||
126 | * nla_get_u32(nla) get payload for a u32 attribute | ||
127 | * nla_get_u64(nla) get payload for a u64 attribute | ||
128 | * nla_get_flag(nla) return 1 if flag is true | ||
129 | * nla_get_msecs(nla) get payload for a msecs attribute | ||
130 | * | ||
131 | * Attribute Misc: | ||
132 | * nla_memcpy(dest, nla, count) copy attribute into memory | ||
133 | * nla_memcmp(nla, data, size) compare attribute with memory area | ||
134 | * nla_strlcpy(dst, nla, size) copy attribute to a sized string | ||
135 | * nla_strcmp(nla, str) compare attribute with string | ||
136 | * | ||
137 | * Attribute Parsing: | ||
138 | * nla_ok(nla, remaining) does nla fit into remaining bytes? | ||
139 | * nla_next(nla, remaining) get next netlink attribute | ||
140 | * nla_validate() validate a stream of attributes | ||
141 | * nla_find() find attribute in stream of attributes | ||
142 | * nla_parse() parse and validate stream of attrs | ||
143 | * nla_parse_nested() parse nested attribuets | ||
144 | * nla_for_each_attr() loop over all attributes | ||
145 | *========================================================================= | ||
146 | */ | ||
147 | |||
148 | /** | ||
149 | * Standard attribute types to specify validation policy | ||
150 | */ | ||
151 | enum { | ||
152 | NLA_UNSPEC, | ||
153 | NLA_U8, | ||
154 | NLA_U16, | ||
155 | NLA_U32, | ||
156 | NLA_U64, | ||
157 | NLA_STRING, | ||
158 | NLA_FLAG, | ||
159 | NLA_MSECS, | ||
160 | NLA_NESTED, | ||
161 | __NLA_TYPE_MAX, | ||
162 | }; | ||
163 | |||
164 | #define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1) | ||
165 | |||
166 | /** | ||
167 | * struct nla_policy - attribute validation policy | ||
168 | * @type: Type of attribute or NLA_UNSPEC | ||
169 | * @minlen: Minimal length of payload required to be available | ||
170 | * | ||
171 | * Policies are defined as arrays of this struct, the array must be | ||
172 | * accessible by attribute type up to the highest identifier to be expected. | ||
173 | * | ||
174 | * Example: | ||
175 | * static struct nla_policy my_policy[ATTR_MAX+1] __read_mostly = { | ||
176 | * [ATTR_FOO] = { .type = NLA_U16 }, | ||
177 | * [ATTR_BAR] = { .type = NLA_STRING }, | ||
178 | * [ATTR_BAZ] = { .minlen = sizeof(struct mystruct) }, | ||
179 | * }; | ||
180 | */ | ||
181 | struct nla_policy { | ||
182 | u16 type; | ||
183 | u16 minlen; | ||
184 | }; | ||
185 | |||
186 | extern void netlink_run_queue(struct sock *sk, unsigned int *qlen, | ||
187 | int (*cb)(struct sk_buff *, | ||
188 | struct nlmsghdr *, int *)); | ||
189 | extern void netlink_queue_skip(struct nlmsghdr *nlh, | ||
190 | struct sk_buff *skb); | ||
191 | |||
192 | extern int nla_validate(struct nlattr *head, int len, int maxtype, | ||
193 | struct nla_policy *policy); | ||
194 | extern int nla_parse(struct nlattr *tb[], int maxtype, | ||
195 | struct nlattr *head, int len, | ||
196 | struct nla_policy *policy); | ||
197 | extern struct nlattr * nla_find(struct nlattr *head, int len, int attrtype); | ||
198 | extern size_t nla_strlcpy(char *dst, const struct nlattr *nla, | ||
199 | size_t dstsize); | ||
200 | extern int nla_memcpy(void *dest, struct nlattr *src, int count); | ||
201 | extern int nla_memcmp(const struct nlattr *nla, const void *data, | ||
202 | size_t size); | ||
203 | extern int nla_strcmp(const struct nlattr *nla, const char *str); | ||
204 | extern struct nlattr * __nla_reserve(struct sk_buff *skb, int attrtype, | ||
205 | int attrlen); | ||
206 | extern struct nlattr * nla_reserve(struct sk_buff *skb, int attrtype, | ||
207 | int attrlen); | ||
208 | extern void __nla_put(struct sk_buff *skb, int attrtype, | ||
209 | int attrlen, const void *data); | ||
210 | extern int nla_put(struct sk_buff *skb, int attrtype, | ||
211 | int attrlen, const void *data); | ||
212 | |||
213 | /************************************************************************** | ||
214 | * Netlink Messages | ||
215 | **************************************************************************/ | ||
216 | |||
217 | /** | ||
218 | * nlmsg_msg_size - length of netlink message not including padding | ||
219 | * @payload: length of message payload | ||
220 | */ | ||
221 | static inline int nlmsg_msg_size(int payload) | ||
222 | { | ||
223 | return NLMSG_HDRLEN + payload; | ||
224 | } | ||
225 | |||
226 | /** | ||
227 | * nlmsg_total_size - length of netlink message including padding | ||
228 | * @payload: length of message payload | ||
229 | */ | ||
230 | static inline int nlmsg_total_size(int payload) | ||
231 | { | ||
232 | return NLMSG_ALIGN(nlmsg_msg_size(payload)); | ||
233 | } | ||
234 | |||
235 | /** | ||
236 | * nlmsg_padlen - length of padding at the message's tail | ||
237 | * @payload: length of message payload | ||
238 | */ | ||
239 | static inline int nlmsg_padlen(int payload) | ||
240 | { | ||
241 | return nlmsg_total_size(payload) - nlmsg_msg_size(payload); | ||
242 | } | ||
243 | |||
244 | /** | ||
245 | * nlmsg_data - head of message payload | ||
246 | * @nlh: netlink messsage header | ||
247 | */ | ||
248 | static inline void *nlmsg_data(const struct nlmsghdr *nlh) | ||
249 | { | ||
250 | return (unsigned char *) nlh + NLMSG_HDRLEN; | ||
251 | } | ||
252 | |||
253 | /** | ||
254 | * nlmsg_len - length of message payload | ||
255 | * @nlh: netlink message header | ||
256 | */ | ||
257 | static inline int nlmsg_len(const struct nlmsghdr *nlh) | ||
258 | { | ||
259 | return nlh->nlmsg_len - NLMSG_HDRLEN; | ||
260 | } | ||
261 | |||
262 | /** | ||
263 | * nlmsg_attrdata - head of attributes data | ||
264 | * @nlh: netlink message header | ||
265 | * @hdrlen: length of family specific header | ||
266 | */ | ||
267 | static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh, | ||
268 | int hdrlen) | ||
269 | { | ||
270 | unsigned char *data = nlmsg_data(nlh); | ||
271 | return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen)); | ||
272 | } | ||
273 | |||
274 | /** | ||
275 | * nlmsg_attrlen - length of attributes data | ||
276 | * @nlh: netlink message header | ||
277 | * @hdrlen: length of family specific header | ||
278 | */ | ||
279 | static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen) | ||
280 | { | ||
281 | return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen); | ||
282 | } | ||
283 | |||
284 | /** | ||
285 | * nlmsg_ok - check if the netlink message fits into the remaining bytes | ||
286 | * @nlh: netlink message header | ||
287 | * @remaining: number of bytes remaining in message stream | ||
288 | */ | ||
289 | static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining) | ||
290 | { | ||
291 | return (remaining >= sizeof(struct nlmsghdr) && | ||
292 | nlh->nlmsg_len >= sizeof(struct nlmsghdr) && | ||
293 | nlh->nlmsg_len <= remaining); | ||
294 | } | ||
295 | |||
296 | /** | ||
297 | * nlmsg_next - next netlink message in message stream | ||
298 | * @nlh: netlink message header | ||
299 | * @remaining: number of bytes remaining in message stream | ||
300 | * | ||
301 | * Returns the next netlink message in the message stream and | ||
302 | * decrements remaining by the size of the current message. | ||
303 | */ | ||
304 | static inline struct nlmsghdr *nlmsg_next(struct nlmsghdr *nlh, int *remaining) | ||
305 | { | ||
306 | int totlen = NLMSG_ALIGN(nlh->nlmsg_len); | ||
307 | |||
308 | *remaining -= totlen; | ||
309 | |||
310 | return (struct nlmsghdr *) ((unsigned char *) nlh + totlen); | ||
311 | } | ||
312 | |||
313 | /** | ||
314 | * nlmsg_parse - parse attributes of a netlink message | ||
315 | * @nlh: netlink message header | ||
316 | * @hdrlen: length of family specific header | ||
317 | * @tb: destination array with maxtype+1 elements | ||
318 | * @maxtype: maximum attribute type to be expected | ||
319 | * @policy: validation policy | ||
320 | * | ||
321 | * See nla_parse() | ||
322 | */ | ||
323 | static inline int nlmsg_parse(struct nlmsghdr *nlh, int hdrlen, | ||
324 | struct nlattr *tb[], int maxtype, | ||
325 | struct nla_policy *policy) | ||
326 | { | ||
327 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | ||
328 | return -EINVAL; | ||
329 | |||
330 | return nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen), | ||
331 | nlmsg_attrlen(nlh, hdrlen), policy); | ||
332 | } | ||
333 | |||
334 | /** | ||
335 | * nlmsg_find_attr - find a specific attribute in a netlink message | ||
336 | * @nlh: netlink message header | ||
337 | * @hdrlen: length of familiy specific header | ||
338 | * @attrtype: type of attribute to look for | ||
339 | * | ||
340 | * Returns the first attribute which matches the specified type. | ||
341 | */ | ||
342 | static inline struct nlattr *nlmsg_find_attr(struct nlmsghdr *nlh, | ||
343 | int hdrlen, int attrtype) | ||
344 | { | ||
345 | return nla_find(nlmsg_attrdata(nlh, hdrlen), | ||
346 | nlmsg_attrlen(nlh, hdrlen), attrtype); | ||
347 | } | ||
348 | |||
349 | /** | ||
350 | * nlmsg_validate - validate a netlink message including attributes | ||
351 | * @nlh: netlinket message header | ||
352 | * @hdrlen: length of familiy specific header | ||
353 | * @maxtype: maximum attribute type to be expected | ||
354 | * @policy: validation policy | ||
355 | */ | ||
356 | static inline int nlmsg_validate(struct nlmsghdr *nlh, int hdrlen, int maxtype, | ||
357 | struct nla_policy *policy) | ||
358 | { | ||
359 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | ||
360 | return -EINVAL; | ||
361 | |||
362 | return nla_validate(nlmsg_attrdata(nlh, hdrlen), | ||
363 | nlmsg_attrlen(nlh, hdrlen), maxtype, policy); | ||
364 | } | ||
365 | |||
366 | /** | ||
367 | * nlmsg_for_each_attr - iterate over a stream of attributes | ||
368 | * @pos: loop counter, set to current attribute | ||
369 | * @nlh: netlink message header | ||
370 | * @hdrlen: length of familiy specific header | ||
371 | * @rem: initialized to len, holds bytes currently remaining in stream | ||
372 | */ | ||
373 | #define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \ | ||
374 | nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \ | ||
375 | nlmsg_attrlen(nlh, hdrlen), rem) | ||
376 | |||
377 | #if 0 | ||
378 | /* FIXME: Enable once all users have been converted */ | ||
379 | |||
380 | /** | ||
381 | * __nlmsg_put - Add a new netlink message to an skb | ||
382 | * @skb: socket buffer to store message in | ||
383 | * @pid: netlink process id | ||
384 | * @seq: sequence number of message | ||
385 | * @type: message type | ||
386 | * @payload: length of message payload | ||
387 | * @flags: message flags | ||
388 | * | ||
389 | * The caller is responsible to ensure that the skb provides enough | ||
390 | * tailroom for both the netlink header and payload. | ||
391 | */ | ||
392 | static inline struct nlmsghdr *__nlmsg_put(struct sk_buff *skb, u32 pid, | ||
393 | u32 seq, int type, int payload, | ||
394 | int flags) | ||
395 | { | ||
396 | struct nlmsghdr *nlh; | ||
397 | |||
398 | nlh = (struct nlmsghdr *) skb_put(skb, nlmsg_total_size(payload)); | ||
399 | nlh->nlmsg_type = type; | ||
400 | nlh->nlmsg_len = nlmsg_msg_size(payload); | ||
401 | nlh->nlmsg_flags = flags; | ||
402 | nlh->nlmsg_pid = pid; | ||
403 | nlh->nlmsg_seq = seq; | ||
404 | |||
405 | memset((unsigned char *) nlmsg_data(nlh) + payload, 0, | ||
406 | nlmsg_padlen(payload)); | ||
407 | |||
408 | return nlh; | ||
409 | } | ||
410 | #endif | ||
411 | |||
412 | /** | ||
413 | * nlmsg_put - Add a new netlink message to an skb | ||
414 | * @skb: socket buffer to store message in | ||
415 | * @pid: netlink process id | ||
416 | * @seq: sequence number of message | ||
417 | * @type: message type | ||
418 | * @payload: length of message payload | ||
419 | * @flags: message flags | ||
420 | * | ||
421 | * Returns NULL if the tailroom of the skb is insufficient to store | ||
422 | * the message header and payload. | ||
423 | */ | ||
424 | static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, | ||
425 | int type, int payload, int flags) | ||
426 | { | ||
427 | if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload))) | ||
428 | return NULL; | ||
429 | |||
430 | return __nlmsg_put(skb, pid, seq, type, payload, flags); | ||
431 | } | ||
432 | |||
433 | /** | ||
434 | * nlmsg_put_answer - Add a new callback based netlink message to an skb | ||
435 | * @skb: socket buffer to store message in | ||
436 | * @cb: netlink callback | ||
437 | * @type: message type | ||
438 | * @payload: length of message payload | ||
439 | * @flags: message flags | ||
440 | * | ||
441 | * Returns NULL if the tailroom of the skb is insufficient to store | ||
442 | * the message header and payload. | ||
443 | */ | ||
444 | static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb, | ||
445 | struct netlink_callback *cb, | ||
446 | int type, int payload, | ||
447 | int flags) | ||
448 | { | ||
449 | return nlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq, | ||
450 | type, payload, flags); | ||
451 | } | ||
452 | |||
453 | /** | ||
454 | * nlmsg_new - Allocate a new netlink message | ||
455 | * @size: maximum size of message | ||
456 | * | ||
457 | * Use NLMSG_GOODSIZE if size isn't know and you need a good default size. | ||
458 | */ | ||
459 | static inline struct sk_buff *nlmsg_new(int size) | ||
460 | { | ||
461 | return alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); | ||
462 | } | ||
463 | |||
464 | /** | ||
465 | * nlmsg_end - Finalize a netlink message | ||
466 | * @skb: socket buffer the message is stored in | ||
467 | * @nlh: netlink message header | ||
468 | * | ||
469 | * Corrects the netlink message header to include the appeneded | ||
470 | * attributes. Only necessary if attributes have been added to | ||
471 | * the message. | ||
472 | * | ||
473 | * Returns the total data length of the skb. | ||
474 | */ | ||
475 | static inline int nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh) | ||
476 | { | ||
477 | nlh->nlmsg_len = skb->tail - (unsigned char *) nlh; | ||
478 | |||
479 | return skb->len; | ||
480 | } | ||
481 | |||
482 | /** | ||
483 | * nlmsg_cancel - Cancel construction of a netlink message | ||
484 | * @skb: socket buffer the message is stored in | ||
485 | * @nlh: netlink message header | ||
486 | * | ||
487 | * Removes the complete netlink message including all | ||
488 | * attributes from the socket buffer again. Returns -1. | ||
489 | */ | ||
490 | static inline int nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh) | ||
491 | { | ||
492 | skb_trim(skb, (unsigned char *) nlh - skb->data); | ||
493 | |||
494 | return -1; | ||
495 | } | ||
496 | |||
497 | /** | ||
498 | * nlmsg_free - free a netlink message | ||
499 | * @skb: socket buffer of netlink message | ||
500 | */ | ||
501 | static inline void nlmsg_free(struct sk_buff *skb) | ||
502 | { | ||
503 | kfree_skb(skb); | ||
504 | } | ||
505 | |||
506 | /** | ||
507 | * nlmsg_multicast - multicast a netlink message | ||
508 | * @sk: netlink socket to spread messages to | ||
509 | * @skb: netlink message as socket buffer | ||
510 | * @pid: own netlink pid to avoid sending to yourself | ||
511 | * @group: multicast group id | ||
512 | */ | ||
513 | static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb, | ||
514 | u32 pid, unsigned int group) | ||
515 | { | ||
516 | int err; | ||
517 | |||
518 | NETLINK_CB(skb).dst_group = group; | ||
519 | |||
520 | err = netlink_broadcast(sk, skb, pid, group, GFP_KERNEL); | ||
521 | if (err > 0) | ||
522 | err = 0; | ||
523 | |||
524 | return err; | ||
525 | } | ||
526 | |||
527 | /** | ||
528 | * nlmsg_unicast - unicast a netlink message | ||
529 | * @sk: netlink socket to spread message to | ||
530 | * @skb: netlink message as socket buffer | ||
531 | * @pid: netlink pid of the destination socket | ||
532 | */ | ||
533 | static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 pid) | ||
534 | { | ||
535 | int err; | ||
536 | |||
537 | err = netlink_unicast(sk, skb, pid, MSG_DONTWAIT); | ||
538 | if (err > 0) | ||
539 | err = 0; | ||
540 | |||
541 | return err; | ||
542 | } | ||
543 | |||
544 | /** | ||
545 | * nlmsg_for_each_msg - iterate over a stream of messages | ||
546 | * @pos: loop counter, set to current message | ||
547 | * @head: head of message stream | ||
548 | * @len: length of message stream | ||
549 | * @rem: initialized to len, holds bytes currently remaining in stream | ||
550 | */ | ||
551 | #define nlmsg_for_each_msg(pos, head, len, rem) \ | ||
552 | for (pos = head, rem = len; \ | ||
553 | nlmsg_ok(pos, rem); \ | ||
554 | pos = nlmsg_next(pos, &(rem))) | ||
555 | |||
556 | /************************************************************************** | ||
557 | * Netlink Attributes | ||
558 | **************************************************************************/ | ||
559 | |||
560 | /** | ||
561 | * nla_attr_size - length of attribute not including padding | ||
562 | * @payload: length of payload | ||
563 | */ | ||
564 | static inline int nla_attr_size(int payload) | ||
565 | { | ||
566 | return NLA_HDRLEN + payload; | ||
567 | } | ||
568 | |||
569 | /** | ||
570 | * nla_total_size - total length of attribute including padding | ||
571 | * @payload: length of payload | ||
572 | */ | ||
573 | static inline int nla_total_size(int payload) | ||
574 | { | ||
575 | return NLA_ALIGN(nla_attr_size(payload)); | ||
576 | } | ||
577 | |||
578 | /** | ||
579 | * nla_padlen - length of padding at the tail of attribute | ||
580 | * @payload: length of payload | ||
581 | */ | ||
582 | static inline int nla_padlen(int payload) | ||
583 | { | ||
584 | return nla_total_size(payload) - nla_attr_size(payload); | ||
585 | } | ||
586 | |||
587 | /** | ||
588 | * nla_data - head of payload | ||
589 | * @nla: netlink attribute | ||
590 | */ | ||
591 | static inline void *nla_data(const struct nlattr *nla) | ||
592 | { | ||
593 | return (char *) nla + NLA_HDRLEN; | ||
594 | } | ||
595 | |||
596 | /** | ||
597 | * nla_len - length of payload | ||
598 | * @nla: netlink attribute | ||
599 | */ | ||
600 | static inline int nla_len(const struct nlattr *nla) | ||
601 | { | ||
602 | return nla->nla_len - NLA_HDRLEN; | ||
603 | } | ||
604 | |||
605 | /** | ||
606 | * nla_ok - check if the netlink attribute fits into the remaining bytes | ||
607 | * @nla: netlink attribute | ||
608 | * @remaining: number of bytes remaining in attribute stream | ||
609 | */ | ||
610 | static inline int nla_ok(const struct nlattr *nla, int remaining) | ||
611 | { | ||
612 | return remaining >= sizeof(*nla) && | ||
613 | nla->nla_len >= sizeof(*nla) && | ||
614 | nla->nla_len <= remaining; | ||
615 | } | ||
616 | |||
617 | /** | ||
618 | * nla_next - next netlink attribte in attribute stream | ||
619 | * @nla: netlink attribute | ||
620 | * @remaining: number of bytes remaining in attribute stream | ||
621 | * | ||
622 | * Returns the next netlink attribute in the attribute stream and | ||
623 | * decrements remaining by the size of the current attribute. | ||
624 | */ | ||
625 | static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining) | ||
626 | { | ||
627 | int totlen = NLA_ALIGN(nla->nla_len); | ||
628 | |||
629 | *remaining -= totlen; | ||
630 | return (struct nlattr *) ((char *) nla + totlen); | ||
631 | } | ||
632 | |||
633 | /** | ||
634 | * nla_parse_nested - parse nested attributes | ||
635 | * @tb: destination array with maxtype+1 elements | ||
636 | * @maxtype: maximum attribute type to be expected | ||
637 | * @nla: attribute containing the nested attributes | ||
638 | * @policy: validation policy | ||
639 | * | ||
640 | * See nla_parse() | ||
641 | */ | ||
642 | static inline int nla_parse_nested(struct nlattr *tb[], int maxtype, | ||
643 | struct nlattr *nla, | ||
644 | struct nla_policy *policy) | ||
645 | { | ||
646 | return nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy); | ||
647 | } | ||
648 | /** | ||
649 | * nla_put_u8 - Add a u16 netlink attribute to a socket buffer | ||
650 | * @skb: socket buffer to add attribute to | ||
651 | * @attrtype: attribute type | ||
652 | * @value: numeric value | ||
653 | */ | ||
654 | static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value) | ||
655 | { | ||
656 | return nla_put(skb, attrtype, sizeof(u8), &value); | ||
657 | } | ||
658 | |||
659 | /** | ||
660 | * nla_put_u16 - Add a u16 netlink attribute to a socket buffer | ||
661 | * @skb: socket buffer to add attribute to | ||
662 | * @attrtype: attribute type | ||
663 | * @value: numeric value | ||
664 | */ | ||
665 | static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value) | ||
666 | { | ||
667 | return nla_put(skb, attrtype, sizeof(u16), &value); | ||
668 | } | ||
669 | |||
670 | /** | ||
671 | * nla_put_u32 - Add a u32 netlink attribute to a socket buffer | ||
672 | * @skb: socket buffer to add attribute to | ||
673 | * @attrtype: attribute type | ||
674 | * @value: numeric value | ||
675 | */ | ||
676 | static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value) | ||
677 | { | ||
678 | return nla_put(skb, attrtype, sizeof(u32), &value); | ||
679 | } | ||
680 | |||
681 | /** | ||
682 | * nla_put_64 - Add a u64 netlink attribute to a socket buffer | ||
683 | * @skb: socket buffer to add attribute to | ||
684 | * @attrtype: attribute type | ||
685 | * @value: numeric value | ||
686 | */ | ||
687 | static inline int nla_put_u64(struct sk_buff *skb, int attrtype, u64 value) | ||
688 | { | ||
689 | return nla_put(skb, attrtype, sizeof(u64), &value); | ||
690 | } | ||
691 | |||
692 | /** | ||
693 | * nla_put_string - Add a string netlink attribute to a socket buffer | ||
694 | * @skb: socket buffer to add attribute to | ||
695 | * @attrtype: attribute type | ||
696 | * @str: NUL terminated string | ||
697 | */ | ||
698 | static inline int nla_put_string(struct sk_buff *skb, int attrtype, | ||
699 | const char *str) | ||
700 | { | ||
701 | return nla_put(skb, attrtype, strlen(str) + 1, str); | ||
702 | } | ||
703 | |||
704 | /** | ||
705 | * nla_put_flag - Add a flag netlink attribute to a socket buffer | ||
706 | * @skb: socket buffer to add attribute to | ||
707 | * @attrtype: attribute type | ||
708 | */ | ||
709 | static inline int nla_put_flag(struct sk_buff *skb, int attrtype) | ||
710 | { | ||
711 | return nla_put(skb, attrtype, 0, NULL); | ||
712 | } | ||
713 | |||
714 | /** | ||
715 | * nla_put_msecs - Add a msecs netlink attribute to a socket buffer | ||
716 | * @skb: socket buffer to add attribute to | ||
717 | * @attrtype: attribute type | ||
718 | * @jiffies: number of msecs in jiffies | ||
719 | */ | ||
720 | static inline int nla_put_msecs(struct sk_buff *skb, int attrtype, | ||
721 | unsigned long jiffies) | ||
722 | { | ||
723 | u64 tmp = jiffies_to_msecs(jiffies); | ||
724 | return nla_put(skb, attrtype, sizeof(u64), &tmp); | ||
725 | } | ||
726 | |||
727 | #define NLA_PUT(skb, attrtype, attrlen, data) \ | ||
728 | do { \ | ||
729 | if (nla_put(skb, attrtype, attrlen, data) < 0) \ | ||
730 | goto nla_put_failure; \ | ||
731 | } while(0) | ||
732 | |||
733 | #define NLA_PUT_TYPE(skb, type, attrtype, value) \ | ||
734 | do { \ | ||
735 | type __tmp = value; \ | ||
736 | NLA_PUT(skb, attrtype, sizeof(type), &__tmp); \ | ||
737 | } while(0) | ||
738 | |||
739 | #define NLA_PUT_U8(skb, attrtype, value) \ | ||
740 | NLA_PUT_TYPE(skb, u8, attrtype, value) | ||
741 | |||
742 | #define NLA_PUT_U16(skb, attrtype, value) \ | ||
743 | NLA_PUT_TYPE(skb, u16, attrtype, value) | ||
744 | |||
745 | #define NLA_PUT_U32(skb, attrtype, value) \ | ||
746 | NLA_PUT_TYPE(skb, u32, attrtype, value) | ||
747 | |||
748 | #define NLA_PUT_U64(skb, attrtype, value) \ | ||
749 | NLA_PUT_TYPE(skb, u64, attrtype, value) | ||
750 | |||
751 | #define NLA_PUT_STRING(skb, attrtype, value) \ | ||
752 | NLA_PUT(skb, attrtype, strlen(value) + 1, value) | ||
753 | |||
754 | #define NLA_PUT_FLAG(skb, attrtype, value) \ | ||
755 | NLA_PUT(skb, attrtype, 0, NULL) | ||
756 | |||
757 | #define NLA_PUT_MSECS(skb, attrtype, jiffies) \ | ||
758 | NLA_PUT_U64(skb, attrtype, jiffies_to_msecs(jiffies)) | ||
759 | |||
760 | /** | ||
761 | * nla_get_u32 - return payload of u32 attribute | ||
762 | * @nla: u32 netlink attribute | ||
763 | */ | ||
764 | static inline u32 nla_get_u32(struct nlattr *nla) | ||
765 | { | ||
766 | return *(u32 *) nla_data(nla); | ||
767 | } | ||
768 | |||
769 | /** | ||
770 | * nla_get_u16 - return payload of u16 attribute | ||
771 | * @nla: u16 netlink attribute | ||
772 | */ | ||
773 | static inline u16 nla_get_u16(struct nlattr *nla) | ||
774 | { | ||
775 | return *(u16 *) nla_data(nla); | ||
776 | } | ||
777 | |||
778 | /** | ||
779 | * nla_get_u8 - return payload of u8 attribute | ||
780 | * @nla: u8 netlink attribute | ||
781 | */ | ||
782 | static inline u8 nla_get_u8(struct nlattr *nla) | ||
783 | { | ||
784 | return *(u8 *) nla_data(nla); | ||
785 | } | ||
786 | |||
787 | /** | ||
788 | * nla_get_u64 - return payload of u64 attribute | ||
789 | * @nla: u64 netlink attribute | ||
790 | */ | ||
791 | static inline u64 nla_get_u64(struct nlattr *nla) | ||
792 | { | ||
793 | u64 tmp; | ||
794 | |||
795 | nla_memcpy(&tmp, nla, sizeof(tmp)); | ||
796 | |||
797 | return tmp; | ||
798 | } | ||
799 | |||
800 | /** | ||
801 | * nla_get_flag - return payload of flag attribute | ||
802 | * @nla: flag netlink attribute | ||
803 | */ | ||
804 | static inline int nla_get_flag(struct nlattr *nla) | ||
805 | { | ||
806 | return !!nla; | ||
807 | } | ||
808 | |||
809 | /** | ||
810 | * nla_get_msecs - return payload of msecs attribute | ||
811 | * @nla: msecs netlink attribute | ||
812 | * | ||
813 | * Returns the number of milliseconds in jiffies. | ||
814 | */ | ||
815 | static inline unsigned long nla_get_msecs(struct nlattr *nla) | ||
816 | { | ||
817 | u64 msecs = nla_get_u64(nla); | ||
818 | |||
819 | return msecs_to_jiffies((unsigned long) msecs); | ||
820 | } | ||
821 | |||
822 | /** | ||
823 | * nla_nest_start - Start a new level of nested attributes | ||
824 | * @skb: socket buffer to add attributes to | ||
825 | * @attrtype: attribute type of container | ||
826 | * | ||
827 | * Returns the container attribute | ||
828 | */ | ||
829 | static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype) | ||
830 | { | ||
831 | struct nlattr *start = (struct nlattr *) skb->tail; | ||
832 | |||
833 | if (nla_put(skb, attrtype, 0, NULL) < 0) | ||
834 | return NULL; | ||
835 | |||
836 | return start; | ||
837 | } | ||
838 | |||
839 | /** | ||
840 | * nla_nest_end - Finalize nesting of attributes | ||
841 | * @skb: socket buffer the attribtues are stored in | ||
842 | * @start: container attribute | ||
843 | * | ||
844 | * Corrects the container attribute header to include the all | ||
845 | * appeneded attributes. | ||
846 | * | ||
847 | * Returns the total data length of the skb. | ||
848 | */ | ||
849 | static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start) | ||
850 | { | ||
851 | start->nla_len = skb->tail - (unsigned char *) start; | ||
852 | return skb->len; | ||
853 | } | ||
854 | |||
855 | /** | ||
856 | * nla_nest_cancel - Cancel nesting of attributes | ||
857 | * @skb: socket buffer the message is stored in | ||
858 | * @start: container attribute | ||
859 | * | ||
860 | * Removes the container attribute and including all nested | ||
861 | * attributes. Returns -1. | ||
862 | */ | ||
863 | static inline int nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) | ||
864 | { | ||
865 | if (start) | ||
866 | skb_trim(skb, (unsigned char *) start - skb->data); | ||
867 | |||
868 | return -1; | ||
869 | } | ||
870 | |||
871 | /** | ||
872 | * nla_for_each_attr - iterate over a stream of attributes | ||
873 | * @pos: loop counter, set to current attribute | ||
874 | * @head: head of attribute stream | ||
875 | * @len: length of attribute stream | ||
876 | * @rem: initialized to len, holds bytes currently remaining in stream | ||
877 | */ | ||
878 | #define nla_for_each_attr(pos, head, len, rem) \ | ||
879 | for (pos = head, rem = len; \ | ||
880 | nla_ok(pos, rem); \ | ||
881 | pos = nla_next(pos, &(rem))) | ||
882 | |||
883 | #endif | ||