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Thomas Grafbfa83a92005-11-10 02:25:51 +01001#ifndef __NET_NETLINK_H
2#define __NET_NETLINK_H
3
4#include <linux/types.h>
5#include <linux/netlink.h>
Al Virod7fe0f22006-12-03 23:15:30 -05006#include <linux/jiffies.h>
Thomas Grafbfa83a92005-11-10 02:25:51 +01007
8/* ========================================================================
9 * Netlink Messages and Attributes Interface (As Seen On TV)
10 * ------------------------------------------------------------------------
11 * Messages Interface
12 * ------------------------------------------------------------------------
13 *
14 * Message Format:
15 * <--- nlmsg_total_size(payload) --->
16 * <-- nlmsg_msg_size(payload) ->
17 * +----------+- - -+-------------+- - -+-------- - -
18 * | nlmsghdr | Pad | Payload | Pad | nlmsghdr
19 * +----------+- - -+-------------+- - -+-------- - -
20 * nlmsg_data(nlh)---^ ^
21 * nlmsg_next(nlh)-----------------------+
22 *
23 * Payload Format:
24 * <---------------------- nlmsg_len(nlh) --------------------->
25 * <------ hdrlen ------> <- nlmsg_attrlen(nlh, hdrlen) ->
26 * +----------------------+- - -+--------------------------------+
27 * | Family Header | Pad | Attributes |
28 * +----------------------+- - -+--------------------------------+
29 * nlmsg_attrdata(nlh, hdrlen)---^
30 *
31 * Data Structures:
32 * struct nlmsghdr netlink message header
33 *
34 * Message Construction:
35 * nlmsg_new() create a new netlink message
36 * nlmsg_put() add a netlink message to an skb
37 * nlmsg_put_answer() callback based nlmsg_put()
Justin P. Mattock1dc8d8c2010-06-21 13:45:42 -070038 * nlmsg_end() finalize netlink message
Thomas Graffe4944e2006-08-04 23:03:05 -070039 * nlmsg_get_pos() return current position in message
40 * nlmsg_trim() trim part of message
Thomas Grafbfa83a92005-11-10 02:25:51 +010041 * nlmsg_cancel() cancel message construction
42 * nlmsg_free() free a netlink message
43 *
44 * Message Sending:
45 * nlmsg_multicast() multicast message to several groups
46 * nlmsg_unicast() unicast a message to a single socket
Thomas Grafd387f6a2006-08-15 00:31:06 -070047 * nlmsg_notify() send notification message
Thomas Grafbfa83a92005-11-10 02:25:51 +010048 *
49 * Message Length Calculations:
50 * nlmsg_msg_size(payload) length of message w/o padding
51 * nlmsg_total_size(payload) length of message w/ padding
52 * nlmsg_padlen(payload) length of padding at tail
53 *
54 * Message Payload Access:
55 * nlmsg_data(nlh) head of message payload
56 * nlmsg_len(nlh) length of message payload
57 * nlmsg_attrdata(nlh, hdrlen) head of attributes data
58 * nlmsg_attrlen(nlh, hdrlen) length of attributes data
59 *
60 * Message Parsing:
61 * nlmsg_ok(nlh, remaining) does nlh fit into remaining bytes?
62 * nlmsg_next(nlh, remaining) get next netlink message
63 * nlmsg_parse() parse attributes of a message
64 * nlmsg_find_attr() find an attribute in a message
65 * nlmsg_for_each_msg() loop over all messages
66 * nlmsg_validate() validate netlink message incl. attrs
67 * nlmsg_for_each_attr() loop over all attributes
68 *
Thomas Graf97676b62006-08-15 00:31:41 -070069 * Misc:
70 * nlmsg_report() report back to application?
71 *
Thomas Grafbfa83a92005-11-10 02:25:51 +010072 * ------------------------------------------------------------------------
73 * Attributes Interface
74 * ------------------------------------------------------------------------
75 *
76 * Attribute Format:
77 * <------- nla_total_size(payload) ------->
78 * <---- nla_attr_size(payload) ----->
79 * +----------+- - -+- - - - - - - - - +- - -+-------- - -
80 * | Header | Pad | Payload | Pad | Header
81 * +----------+- - -+- - - - - - - - - +- - -+-------- - -
82 * <- nla_len(nla) -> ^
83 * nla_data(nla)----^ |
84 * nla_next(nla)-----------------------------'
85 *
86 * Data Structures:
Pierre Ynardd1ec3b72007-10-10 21:09:48 -070087 * struct nlattr netlink attribute header
Thomas Grafbfa83a92005-11-10 02:25:51 +010088 *
89 * Attribute Construction:
Thomas Graffe4944e2006-08-04 23:03:05 -070090 * nla_reserve(skb, type, len) reserve room for an attribute
91 * nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr
Thomas Grafbfa83a92005-11-10 02:25:51 +010092 * nla_put(skb, type, len, data) add attribute to skb
Thomas Graffe4944e2006-08-04 23:03:05 -070093 * nla_put_nohdr(skb, len, data) add attribute w/o hdr
Patrick McHardy01480e12008-01-22 22:10:59 -080094 * nla_append(skb, len, data) append data to skb
Thomas Grafbfa83a92005-11-10 02:25:51 +010095 *
96 * Attribute Construction for Basic Types:
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 * Exceptions Based Attribute Construction:
106 * NLA_PUT(skb, type, len, data) add attribute to skb
107 * NLA_PUT_U8(skb, type, value) add u8 attribute to skb
108 * NLA_PUT_U16(skb, type, value) add u16 attribute to skb
109 * NLA_PUT_U32(skb, type, value) add u32 attribute to skb
110 * NLA_PUT_U64(skb, type, value) add u64 attribute to skb
111 * NLA_PUT_STRING(skb, type, str) add string attribute to skb
112 * NLA_PUT_FLAG(skb, type) add flag attribute to skb
113 * NLA_PUT_MSECS(skb, type, jiffies) add msecs attribute to skb
114 *
115 * The meaning of these functions is equal to their lower case
116 * variants but they jump to the label nla_put_failure in case
117 * of a failure.
118 *
119 * Nested Attributes Construction:
120 * nla_nest_start(skb, type) start a nested attribute
121 * nla_nest_end(skb, nla) finalize a nested attribute
122 * nla_nest_cancel(skb, nla) cancel nested attribute construction
123 *
124 * Attribute Length Calculations:
125 * nla_attr_size(payload) length of attribute w/o padding
126 * nla_total_size(payload) length of attribute w/ padding
127 * nla_padlen(payload) length of padding
128 *
129 * Attribute Payload Access:
130 * nla_data(nla) head of attribute payload
131 * nla_len(nla) length of attribute payload
132 *
133 * Attribute Payload Access for Basic Types:
134 * nla_get_u8(nla) get payload for a u8 attribute
135 * nla_get_u16(nla) get payload for a u16 attribute
136 * nla_get_u32(nla) get payload for a u32 attribute
137 * nla_get_u64(nla) get payload for a u64 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
Paul Moore4fe5d5c2006-09-25 15:54:03 -0700151 * nla_validate_nested() validate a stream of nested attributes
Thomas Grafbfa83a92005-11-10 02:25:51 +0100152 * nla_find() find attribute in stream of attributes
Thomas Graffe4944e2006-08-04 23:03:05 -0700153 * nla_find_nested() find attribute in nested attributes
Thomas Grafbfa83a92005-11-10 02:25:51 +0100154 * nla_parse() parse and validate stream of attrs
155 * nla_parse_nested() parse nested attribuets
156 * nla_for_each_attr() loop over all attributes
Paul Moore22acb192006-09-25 15:53:37 -0700157 * nla_for_each_nested() loop over the nested attributes
Thomas Grafbfa83a92005-11-10 02:25:51 +0100158 *=========================================================================
159 */
160
161 /**
162 * Standard attribute types to specify validation policy
163 */
164enum {
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,
Patrick McHardy1092cb22007-06-25 13:49:35 -0700174 NLA_NESTED_COMPAT,
Thomas Grafa5531a52006-08-26 20:11:47 -0700175 NLA_NUL_STRING,
Johannes Bergd30045a2007-03-23 11:37:48 -0700176 NLA_BINARY,
Thomas Grafbfa83a92005-11-10 02:25:51 +0100177 __NLA_TYPE_MAX,
178};
179
180#define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1)
181
182/**
183 * struct nla_policy - attribute validation policy
184 * @type: Type of attribute or NLA_UNSPEC
Thomas Grafa5531a52006-08-26 20:11:47 -0700185 * @len: Type specific length of payload
Thomas Grafbfa83a92005-11-10 02:25:51 +0100186 *
187 * Policies are defined as arrays of this struct, the array must be
188 * accessible by attribute type up to the highest identifier to be expected.
189 *
Thomas Grafa5531a52006-08-26 20:11:47 -0700190 * Meaning of `len' field:
191 * NLA_STRING Maximum length of string
192 * NLA_NUL_STRING Maximum length of string (excluding NUL)
193 * NLA_FLAG Unused
Johannes Bergd30045a2007-03-23 11:37:48 -0700194 * NLA_BINARY Maximum length of attribute payload
Johannes Berg4b6cc722011-11-03 00:10:05 +0000195 * NLA_NESTED Don't use `len' field -- length verification is
196 * done by checking len of nested header (or empty)
197 * NLA_NESTED_COMPAT Minimum length of structure payload
198 * NLA_U8, NLA_U16,
199 * NLA_U32, NLA_U64,
200 * NLA_MSECS Leaving the length field zero will verify the
201 * given type fits, using it verifies minimum length
202 * just like "All other"
203 * All other Minimum length of attribute payload
Thomas Grafa5531a52006-08-26 20:11:47 -0700204 *
Thomas Grafbfa83a92005-11-10 02:25:51 +0100205 * Example:
Alexey Dobriyanb54452b2010-02-18 08:14:31 +0000206 * static const struct nla_policy my_policy[ATTR_MAX+1] = {
Thomas Grafbfa83a92005-11-10 02:25:51 +0100207 * [ATTR_FOO] = { .type = NLA_U16 },
Johannes Bergd30045a2007-03-23 11:37:48 -0700208 * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ },
Thomas Grafa5531a52006-08-26 20:11:47 -0700209 * [ATTR_BAZ] = { .len = sizeof(struct mystruct) },
Thomas Grafbfa83a92005-11-10 02:25:51 +0100210 * };
211 */
212struct nla_policy {
213 u16 type;
Thomas Grafa5531a52006-08-26 20:11:47 -0700214 u16 len;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100215};
216
Thomas Graf4e902c52006-08-17 18:14:52 -0700217/**
218 * struct nl_info - netlink source information
219 * @nlh: Netlink message header of original request
220 * @pid: Netlink PID of requesting application
221 */
222struct nl_info {
223 struct nlmsghdr *nlh;
Denis V. Lunev4d1169c2008-01-10 03:26:13 -0800224 struct net *nl_net;
Thomas Graf4e902c52006-08-17 18:14:52 -0700225 u32 pid;
226};
227
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -0700228extern int netlink_rcv_skb(struct sk_buff *skb,
229 int (*cb)(struct sk_buff *,
230 struct nlmsghdr *));
Thomas Graf97676b62006-08-15 00:31:41 -0700231extern int nlmsg_notify(struct sock *sk, struct sk_buff *skb,
232 u32 pid, unsigned int group, int report,
233 gfp_t flags);
Thomas Graf82ace472005-11-10 02:25:53 +0100234
Jan Engelhardt36546542010-11-16 09:52:32 -0800235extern int nla_validate(const struct nlattr *head,
236 int len, int maxtype,
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700237 const struct nla_policy *policy);
Jan Engelhardt36546542010-11-16 09:52:32 -0800238extern int nla_parse(struct nlattr **tb, int maxtype,
239 const struct nlattr *head, int len,
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700240 const struct nla_policy *policy);
Holger Eitzenbergere487eb92009-03-25 18:26:30 +0100241extern int nla_policy_len(const struct nla_policy *, int);
Jan Engelhardt36546542010-11-16 09:52:32 -0800242extern struct nlattr * nla_find(const struct nlattr *head,
243 int len, int attrtype);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100244extern size_t nla_strlcpy(char *dst, const struct nlattr *nla,
245 size_t dstsize);
Patrick McHardyb057efd2008-10-28 11:59:11 -0700246extern int nla_memcpy(void *dest, const struct nlattr *src, int count);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100247extern int nla_memcmp(const struct nlattr *nla, const void *data,
248 size_t size);
249extern int nla_strcmp(const struct nlattr *nla, const char *str);
250extern struct nlattr * __nla_reserve(struct sk_buff *skb, int attrtype,
251 int attrlen);
Thomas Graffe4944e2006-08-04 23:03:05 -0700252extern void * __nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100253extern struct nlattr * nla_reserve(struct sk_buff *skb, int attrtype,
254 int attrlen);
Thomas Graffe4944e2006-08-04 23:03:05 -0700255extern void * nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100256extern void __nla_put(struct sk_buff *skb, int attrtype,
257 int attrlen, const void *data);
Thomas Graffe4944e2006-08-04 23:03:05 -0700258extern void __nla_put_nohdr(struct sk_buff *skb, int attrlen,
259 const void *data);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100260extern int nla_put(struct sk_buff *skb, int attrtype,
261 int attrlen, const void *data);
Thomas Graffe4944e2006-08-04 23:03:05 -0700262extern int nla_put_nohdr(struct sk_buff *skb, int attrlen,
263 const void *data);
Patrick McHardy01480e12008-01-22 22:10:59 -0800264extern int nla_append(struct sk_buff *skb, int attrlen,
265 const void *data);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100266
267/**************************************************************************
268 * Netlink Messages
269 **************************************************************************/
270
271/**
272 * nlmsg_msg_size - length of netlink message not including padding
273 * @payload: length of message payload
274 */
275static inline int nlmsg_msg_size(int payload)
276{
277 return NLMSG_HDRLEN + payload;
278}
279
280/**
281 * nlmsg_total_size - length of netlink message including padding
282 * @payload: length of message payload
283 */
284static inline int nlmsg_total_size(int payload)
285{
286 return NLMSG_ALIGN(nlmsg_msg_size(payload));
287}
288
289/**
290 * nlmsg_padlen - length of padding at the message's tail
291 * @payload: length of message payload
292 */
293static inline int nlmsg_padlen(int payload)
294{
295 return nlmsg_total_size(payload) - nlmsg_msg_size(payload);
296}
297
298/**
299 * nlmsg_data - head of message payload
Justin P. Mattock70f23fd2011-05-10 10:16:21 +0200300 * @nlh: netlink message header
Thomas Grafbfa83a92005-11-10 02:25:51 +0100301 */
302static inline void *nlmsg_data(const struct nlmsghdr *nlh)
303{
304 return (unsigned char *) nlh + NLMSG_HDRLEN;
305}
306
307/**
308 * nlmsg_len - length of message payload
309 * @nlh: netlink message header
310 */
311static inline int nlmsg_len(const struct nlmsghdr *nlh)
312{
313 return nlh->nlmsg_len - NLMSG_HDRLEN;
314}
315
316/**
317 * nlmsg_attrdata - head of attributes data
318 * @nlh: netlink message header
319 * @hdrlen: length of family specific header
320 */
321static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh,
322 int hdrlen)
323{
324 unsigned char *data = nlmsg_data(nlh);
325 return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen));
326}
327
328/**
329 * nlmsg_attrlen - length of attributes data
330 * @nlh: netlink message header
331 * @hdrlen: length of family specific header
332 */
333static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen)
334{
335 return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen);
336}
337
338/**
339 * nlmsg_ok - check if the netlink message fits into the remaining bytes
340 * @nlh: netlink message header
341 * @remaining: number of bytes remaining in message stream
342 */
343static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining)
344{
Vegard Nossum619e8032008-12-25 17:21:17 -0800345 return (remaining >= (int) sizeof(struct nlmsghdr) &&
Thomas Grafbfa83a92005-11-10 02:25:51 +0100346 nlh->nlmsg_len >= sizeof(struct nlmsghdr) &&
347 nlh->nlmsg_len <= remaining);
348}
349
350/**
351 * nlmsg_next - next netlink message in message stream
352 * @nlh: netlink message header
353 * @remaining: number of bytes remaining in message stream
354 *
355 * Returns the next netlink message in the message stream and
356 * decrements remaining by the size of the current message.
357 */
Jan Engelhardt36546542010-11-16 09:52:32 -0800358static inline struct nlmsghdr *
359nlmsg_next(const struct nlmsghdr *nlh, int *remaining)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100360{
361 int totlen = NLMSG_ALIGN(nlh->nlmsg_len);
362
363 *remaining -= totlen;
364
365 return (struct nlmsghdr *) ((unsigned char *) nlh + totlen);
366}
367
368/**
369 * nlmsg_parse - parse attributes of a netlink message
370 * @nlh: netlink message header
371 * @hdrlen: length of family specific header
372 * @tb: destination array with maxtype+1 elements
373 * @maxtype: maximum attribute type to be expected
374 * @policy: validation policy
375 *
376 * See nla_parse()
377 */
Patrick McHardy3a6c2b42009-08-25 16:07:40 +0200378static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen,
Thomas Grafbfa83a92005-11-10 02:25:51 +0100379 struct nlattr *tb[], int maxtype,
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700380 const struct nla_policy *policy)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100381{
382 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
383 return -EINVAL;
384
385 return nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen),
386 nlmsg_attrlen(nlh, hdrlen), policy);
387}
388
389/**
390 * nlmsg_find_attr - find a specific attribute in a netlink message
391 * @nlh: netlink message header
392 * @hdrlen: length of familiy specific header
393 * @attrtype: type of attribute to look for
394 *
395 * Returns the first attribute which matches the specified type.
396 */
Nelson Elhage6b8c92b2010-11-03 16:35:40 +0000397static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh,
Thomas Grafbfa83a92005-11-10 02:25:51 +0100398 int hdrlen, int attrtype)
399{
400 return nla_find(nlmsg_attrdata(nlh, hdrlen),
401 nlmsg_attrlen(nlh, hdrlen), attrtype);
402}
403
404/**
405 * nlmsg_validate - validate a netlink message including attributes
406 * @nlh: netlinket message header
407 * @hdrlen: length of familiy specific header
408 * @maxtype: maximum attribute type to be expected
409 * @policy: validation policy
410 */
Jan Engelhardt36546542010-11-16 09:52:32 -0800411static inline int nlmsg_validate(const struct nlmsghdr *nlh,
412 int hdrlen, int maxtype,
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700413 const struct nla_policy *policy)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100414{
415 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
416 return -EINVAL;
417
418 return nla_validate(nlmsg_attrdata(nlh, hdrlen),
419 nlmsg_attrlen(nlh, hdrlen), maxtype, policy);
420}
421
422/**
Thomas Graf97676b62006-08-15 00:31:41 -0700423 * nlmsg_report - need to report back to application?
424 * @nlh: netlink message header
425 *
426 * Returns 1 if a report back to the application is requested.
427 */
Patrick McHardy3a6c2b42009-08-25 16:07:40 +0200428static inline int nlmsg_report(const struct nlmsghdr *nlh)
Thomas Graf97676b62006-08-15 00:31:41 -0700429{
430 return !!(nlh->nlmsg_flags & NLM_F_ECHO);
431}
432
433/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100434 * nlmsg_for_each_attr - iterate over a stream of attributes
435 * @pos: loop counter, set to current attribute
436 * @nlh: netlink message header
437 * @hdrlen: length of familiy specific header
438 * @rem: initialized to len, holds bytes currently remaining in stream
439 */
440#define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \
441 nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \
442 nlmsg_attrlen(nlh, hdrlen), rem)
443
Thomas Grafbfa83a92005-11-10 02:25:51 +0100444/**
445 * nlmsg_put - Add a new netlink message to an skb
446 * @skb: socket buffer to store message in
447 * @pid: netlink process id
448 * @seq: sequence number of message
449 * @type: message type
450 * @payload: length of message payload
451 * @flags: message flags
452 *
453 * Returns NULL if the tailroom of the skb is insufficient to store
454 * the message header and payload.
455 */
456static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
457 int type, int payload, int flags)
458{
459 if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload)))
460 return NULL;
461
462 return __nlmsg_put(skb, pid, seq, type, payload, flags);
463}
464
465/**
466 * nlmsg_put_answer - Add a new callback based netlink message to an skb
467 * @skb: socket buffer to store message in
468 * @cb: netlink callback
469 * @type: message type
470 * @payload: length of message payload
471 * @flags: message flags
472 *
473 * Returns NULL if the tailroom of the skb is insufficient to store
474 * the message header and payload.
475 */
476static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb,
477 struct netlink_callback *cb,
478 int type, int payload,
479 int flags)
480{
481 return nlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
482 type, payload, flags);
483}
484
485/**
486 * nlmsg_new - Allocate a new netlink message
Thomas Graf339bf982006-11-10 14:10:15 -0800487 * @payload: size of the message payload
Thomas Graffe4944e2006-08-04 23:03:05 -0700488 * @flags: the type of memory to allocate.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100489 *
Thomas Graf339bf982006-11-10 14:10:15 -0800490 * Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known
491 * and a good default is needed.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100492 */
Thomas Graf339bf982006-11-10 14:10:15 -0800493static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100494{
Thomas Graf339bf982006-11-10 14:10:15 -0800495 return alloc_skb(nlmsg_total_size(payload), flags);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100496}
497
498/**
499 * nlmsg_end - Finalize a netlink message
500 * @skb: socket buffer the message is stored in
501 * @nlh: netlink message header
502 *
503 * Corrects the netlink message header to include the appeneded
504 * attributes. Only necessary if attributes have been added to
505 * the message.
506 *
507 * Returns the total data length of the skb.
508 */
509static inline int nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh)
510{
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700511 nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100512
513 return skb->len;
514}
515
516/**
Thomas Graffe4944e2006-08-04 23:03:05 -0700517 * nlmsg_get_pos - return current position in netlink message
518 * @skb: socket buffer the message is stored in
519 *
520 * Returns a pointer to the current tail of the message.
521 */
522static inline void *nlmsg_get_pos(struct sk_buff *skb)
523{
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700524 return skb_tail_pointer(skb);
Thomas Graffe4944e2006-08-04 23:03:05 -0700525}
526
527/**
528 * nlmsg_trim - Trim message to a mark
529 * @skb: socket buffer the message is stored in
530 * @mark: mark to trim to
531 *
Thomas Grafbc3ed282008-06-03 16:36:54 -0700532 * Trims the message to the provided mark.
Thomas Graffe4944e2006-08-04 23:03:05 -0700533 */
Thomas Grafbc3ed282008-06-03 16:36:54 -0700534static inline void nlmsg_trim(struct sk_buff *skb, const void *mark)
Thomas Graffe4944e2006-08-04 23:03:05 -0700535{
536 if (mark)
537 skb_trim(skb, (unsigned char *) mark - skb->data);
Thomas Graffe4944e2006-08-04 23:03:05 -0700538}
539
540/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100541 * nlmsg_cancel - Cancel construction of a netlink message
542 * @skb: socket buffer the message is stored in
543 * @nlh: netlink message header
544 *
545 * Removes the complete netlink message including all
Thomas Grafbc3ed282008-06-03 16:36:54 -0700546 * attributes from the socket buffer again.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100547 */
Thomas Grafbc3ed282008-06-03 16:36:54 -0700548static inline void nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100549{
Thomas Grafbc3ed282008-06-03 16:36:54 -0700550 nlmsg_trim(skb, nlh);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100551}
552
553/**
554 * nlmsg_free - free a netlink message
555 * @skb: socket buffer of netlink message
556 */
557static inline void nlmsg_free(struct sk_buff *skb)
558{
559 kfree_skb(skb);
560}
561
562/**
563 * nlmsg_multicast - multicast a netlink message
564 * @sk: netlink socket to spread messages to
565 * @skb: netlink message as socket buffer
566 * @pid: own netlink pid to avoid sending to yourself
567 * @group: multicast group id
Thomas Grafd387f6a2006-08-15 00:31:06 -0700568 * @flags: allocation flags
Thomas Grafbfa83a92005-11-10 02:25:51 +0100569 */
570static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb,
Thomas Grafd387f6a2006-08-15 00:31:06 -0700571 u32 pid, unsigned int group, gfp_t flags)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100572{
573 int err;
574
575 NETLINK_CB(skb).dst_group = group;
576
Thomas Grafd387f6a2006-08-15 00:31:06 -0700577 err = netlink_broadcast(sk, skb, pid, group, flags);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100578 if (err > 0)
579 err = 0;
580
581 return err;
582}
583
584/**
585 * nlmsg_unicast - unicast a netlink message
586 * @sk: netlink socket to spread message to
587 * @skb: netlink message as socket buffer
588 * @pid: netlink pid of the destination socket
589 */
590static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 pid)
591{
592 int err;
593
594 err = netlink_unicast(sk, skb, pid, MSG_DONTWAIT);
595 if (err > 0)
596 err = 0;
597
598 return err;
599}
600
601/**
602 * nlmsg_for_each_msg - iterate over a stream of messages
603 * @pos: loop counter, set to current message
604 * @head: head of message stream
605 * @len: length of message stream
606 * @rem: initialized to len, holds bytes currently remaining in stream
607 */
608#define nlmsg_for_each_msg(pos, head, len, rem) \
609 for (pos = head, rem = len; \
610 nlmsg_ok(pos, rem); \
611 pos = nlmsg_next(pos, &(rem)))
612
Johannes Berg670dc282011-06-20 13:40:46 +0200613/**
614 * nl_dump_check_consistent - check if sequence is consistent and advertise if not
615 * @cb: netlink callback structure that stores the sequence number
616 * @nlh: netlink message header to write the flag to
617 *
618 * This function checks if the sequence (generation) number changed during dump
619 * and if it did, advertises it in the netlink message header.
620 *
621 * The correct way to use it is to set cb->seq to the generation counter when
622 * all locks for dumping have been acquired, and then call this function for
623 * each message that is generated.
624 *
625 * Note that due to initialisation concerns, 0 is an invalid sequence number
626 * and must not be used by code that uses this functionality.
627 */
628static inline void
629nl_dump_check_consistent(struct netlink_callback *cb,
630 struct nlmsghdr *nlh)
631{
632 if (cb->prev_seq && cb->seq != cb->prev_seq)
633 nlh->nlmsg_flags |= NLM_F_DUMP_INTR;
634 cb->prev_seq = cb->seq;
635}
636
Thomas Grafbfa83a92005-11-10 02:25:51 +0100637/**************************************************************************
638 * Netlink Attributes
639 **************************************************************************/
640
641/**
642 * nla_attr_size - length of attribute not including padding
643 * @payload: length of payload
644 */
645static inline int nla_attr_size(int payload)
646{
647 return NLA_HDRLEN + payload;
648}
649
650/**
651 * nla_total_size - total length of attribute including padding
652 * @payload: length of payload
653 */
654static inline int nla_total_size(int payload)
655{
656 return NLA_ALIGN(nla_attr_size(payload));
657}
658
659/**
660 * nla_padlen - length of padding at the tail of attribute
661 * @payload: length of payload
662 */
663static inline int nla_padlen(int payload)
664{
665 return nla_total_size(payload) - nla_attr_size(payload);
666}
667
668/**
Thomas Graf8f4c1f92007-09-12 14:44:36 +0200669 * nla_type - attribute type
670 * @nla: netlink attribute
671 */
672static inline int nla_type(const struct nlattr *nla)
673{
674 return nla->nla_type & NLA_TYPE_MASK;
675}
676
677/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100678 * nla_data - head of payload
679 * @nla: netlink attribute
680 */
681static inline void *nla_data(const struct nlattr *nla)
682{
683 return (char *) nla + NLA_HDRLEN;
684}
685
686/**
687 * nla_len - length of payload
688 * @nla: netlink attribute
689 */
690static inline int nla_len(const struct nlattr *nla)
691{
692 return nla->nla_len - NLA_HDRLEN;
693}
694
695/**
696 * nla_ok - check if the netlink attribute fits into the remaining bytes
697 * @nla: netlink attribute
698 * @remaining: number of bytes remaining in attribute stream
699 */
700static inline int nla_ok(const struct nlattr *nla, int remaining)
701{
Vegard Nossum1045b032008-09-11 19:05:29 -0700702 return remaining >= (int) sizeof(*nla) &&
Thomas Grafbfa83a92005-11-10 02:25:51 +0100703 nla->nla_len >= sizeof(*nla) &&
704 nla->nla_len <= remaining;
705}
706
707/**
Pierre Ynardd1ec3b72007-10-10 21:09:48 -0700708 * nla_next - next netlink attribute in attribute stream
Thomas Grafbfa83a92005-11-10 02:25:51 +0100709 * @nla: netlink attribute
710 * @remaining: number of bytes remaining in attribute stream
711 *
712 * Returns the next netlink attribute in the attribute stream and
713 * decrements remaining by the size of the current attribute.
714 */
715static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining)
716{
717 int totlen = NLA_ALIGN(nla->nla_len);
718
719 *remaining -= totlen;
720 return (struct nlattr *) ((char *) nla + totlen);
721}
722
723/**
Thomas Graffe4944e2006-08-04 23:03:05 -0700724 * nla_find_nested - find attribute in a set of nested attributes
725 * @nla: attribute containing the nested attributes
726 * @attrtype: type of attribute to look for
727 *
728 * Returns the first attribute which matches the specified type.
729 */
Jan Engelhardt36546542010-11-16 09:52:32 -0800730static inline struct nlattr *
731nla_find_nested(const struct nlattr *nla, int attrtype)
Thomas Graffe4944e2006-08-04 23:03:05 -0700732{
733 return nla_find(nla_data(nla), nla_len(nla), attrtype);
734}
735
736/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100737 * nla_parse_nested - parse nested attributes
738 * @tb: destination array with maxtype+1 elements
739 * @maxtype: maximum attribute type to be expected
740 * @nla: attribute containing the nested attributes
741 * @policy: validation policy
742 *
743 * See nla_parse()
744 */
745static inline int nla_parse_nested(struct nlattr *tb[], int maxtype,
Patrick McHardyb057efd2008-10-28 11:59:11 -0700746 const struct nlattr *nla,
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700747 const struct nla_policy *policy)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100748{
749 return nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy);
750}
Patrick McHardy1092cb22007-06-25 13:49:35 -0700751
752/**
Pierre Ynardd1ec3b72007-10-10 21:09:48 -0700753 * nla_put_u8 - Add a u8 netlink attribute to a socket buffer
Thomas Grafbfa83a92005-11-10 02:25:51 +0100754 * @skb: socket buffer to add attribute to
755 * @attrtype: attribute type
756 * @value: numeric value
757 */
758static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value)
759{
760 return nla_put(skb, attrtype, sizeof(u8), &value);
761}
762
763/**
764 * nla_put_u16 - Add a u16 netlink attribute to a socket buffer
765 * @skb: socket buffer to add attribute to
766 * @attrtype: attribute type
767 * @value: numeric value
768 */
769static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value)
770{
771 return nla_put(skb, attrtype, sizeof(u16), &value);
772}
773
774/**
775 * nla_put_u32 - Add a u32 netlink attribute to a socket buffer
776 * @skb: socket buffer to add attribute to
777 * @attrtype: attribute type
778 * @value: numeric value
779 */
780static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value)
781{
782 return nla_put(skb, attrtype, sizeof(u32), &value);
783}
784
785/**
786 * nla_put_64 - Add a u64 netlink attribute to a socket buffer
787 * @skb: socket buffer to add attribute to
788 * @attrtype: attribute type
789 * @value: numeric value
790 */
791static inline int nla_put_u64(struct sk_buff *skb, int attrtype, u64 value)
792{
793 return nla_put(skb, attrtype, sizeof(u64), &value);
794}
795
796/**
797 * nla_put_string - Add a string netlink attribute to a socket buffer
798 * @skb: socket buffer to add attribute to
799 * @attrtype: attribute type
800 * @str: NUL terminated string
801 */
802static inline int nla_put_string(struct sk_buff *skb, int attrtype,
803 const char *str)
804{
805 return nla_put(skb, attrtype, strlen(str) + 1, str);
806}
807
808/**
809 * nla_put_flag - Add a flag netlink attribute to a socket buffer
810 * @skb: socket buffer to add attribute to
811 * @attrtype: attribute type
812 */
813static inline int nla_put_flag(struct sk_buff *skb, int attrtype)
814{
815 return nla_put(skb, attrtype, 0, NULL);
816}
817
818/**
819 * nla_put_msecs - Add a msecs netlink attribute to a socket buffer
820 * @skb: socket buffer to add attribute to
821 * @attrtype: attribute type
822 * @jiffies: number of msecs in jiffies
823 */
824static inline int nla_put_msecs(struct sk_buff *skb, int attrtype,
825 unsigned long jiffies)
826{
827 u64 tmp = jiffies_to_msecs(jiffies);
828 return nla_put(skb, attrtype, sizeof(u64), &tmp);
829}
830
831#define NLA_PUT(skb, attrtype, attrlen, data) \
832 do { \
Patrick McHardyf4d900a2007-12-05 03:31:53 -0800833 if (unlikely(nla_put(skb, attrtype, attrlen, data) < 0)) \
Thomas Grafbfa83a92005-11-10 02:25:51 +0100834 goto nla_put_failure; \
835 } while(0)
836
837#define NLA_PUT_TYPE(skb, type, attrtype, value) \
838 do { \
839 type __tmp = value; \
840 NLA_PUT(skb, attrtype, sizeof(type), &__tmp); \
841 } while(0)
842
843#define NLA_PUT_U8(skb, attrtype, value) \
844 NLA_PUT_TYPE(skb, u8, attrtype, value)
845
846#define NLA_PUT_U16(skb, attrtype, value) \
847 NLA_PUT_TYPE(skb, u16, attrtype, value)
848
Thomas Graf4a89c252006-11-24 17:14:51 -0800849#define NLA_PUT_LE16(skb, attrtype, value) \
850 NLA_PUT_TYPE(skb, __le16, attrtype, value)
851
Patrick McHardy838965b2007-12-17 22:29:26 -0800852#define NLA_PUT_BE16(skb, attrtype, value) \
853 NLA_PUT_TYPE(skb, __be16, attrtype, value)
854
Jozsef Kadlecsikf7036512011-02-01 15:20:14 +0100855#define NLA_PUT_NET16(skb, attrtype, value) \
856 NLA_PUT_BE16(skb, attrtype | NLA_F_NET_BYTEORDER, value)
857
Thomas Grafbfa83a92005-11-10 02:25:51 +0100858#define NLA_PUT_U32(skb, attrtype, value) \
859 NLA_PUT_TYPE(skb, u32, attrtype, value)
860
Al Viro00012e52006-09-26 22:14:41 -0700861#define NLA_PUT_BE32(skb, attrtype, value) \
862 NLA_PUT_TYPE(skb, __be32, attrtype, value)
863
Jozsef Kadlecsikf7036512011-02-01 15:20:14 +0100864#define NLA_PUT_NET32(skb, attrtype, value) \
865 NLA_PUT_BE32(skb, attrtype | NLA_F_NET_BYTEORDER, value)
866
Thomas Grafbfa83a92005-11-10 02:25:51 +0100867#define NLA_PUT_U64(skb, attrtype, value) \
868 NLA_PUT_TYPE(skb, u64, attrtype, value)
869
Krzysztof Piotr Oledzki07a7c102008-07-21 10:01:14 -0700870#define NLA_PUT_BE64(skb, attrtype, value) \
871 NLA_PUT_TYPE(skb, __be64, attrtype, value)
872
Jozsef Kadlecsikf7036512011-02-01 15:20:14 +0100873#define NLA_PUT_NET64(skb, attrtype, value) \
874 NLA_PUT_BE64(skb, attrtype | NLA_F_NET_BYTEORDER, value)
875
Thomas Grafbfa83a92005-11-10 02:25:51 +0100876#define NLA_PUT_STRING(skb, attrtype, value) \
877 NLA_PUT(skb, attrtype, strlen(value) + 1, value)
878
Johannes Bergff5dfe72006-08-26 19:17:53 -0700879#define NLA_PUT_FLAG(skb, attrtype) \
Thomas Grafbfa83a92005-11-10 02:25:51 +0100880 NLA_PUT(skb, attrtype, 0, NULL)
881
882#define NLA_PUT_MSECS(skb, attrtype, jiffies) \
883 NLA_PUT_U64(skb, attrtype, jiffies_to_msecs(jiffies))
884
885/**
886 * nla_get_u32 - return payload of u32 attribute
887 * @nla: u32 netlink attribute
888 */
Patrick McHardyb057efd2008-10-28 11:59:11 -0700889static inline u32 nla_get_u32(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100890{
891 return *(u32 *) nla_data(nla);
892}
893
894/**
Al Viro00012e52006-09-26 22:14:41 -0700895 * nla_get_be32 - return payload of __be32 attribute
896 * @nla: __be32 netlink attribute
897 */
Patrick McHardyb057efd2008-10-28 11:59:11 -0700898static inline __be32 nla_get_be32(const struct nlattr *nla)
Al Viro00012e52006-09-26 22:14:41 -0700899{
900 return *(__be32 *) nla_data(nla);
901}
902
903/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100904 * nla_get_u16 - return payload of u16 attribute
905 * @nla: u16 netlink attribute
906 */
Patrick McHardyb057efd2008-10-28 11:59:11 -0700907static inline u16 nla_get_u16(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100908{
909 return *(u16 *) nla_data(nla);
910}
911
912/**
Patrick McHardy838965b2007-12-17 22:29:26 -0800913 * nla_get_be16 - return payload of __be16 attribute
914 * @nla: __be16 netlink attribute
915 */
Patrick McHardyb057efd2008-10-28 11:59:11 -0700916static inline __be16 nla_get_be16(const struct nlattr *nla)
Patrick McHardy838965b2007-12-17 22:29:26 -0800917{
918 return *(__be16 *) nla_data(nla);
919}
920
921/**
Thomas Graf4a89c252006-11-24 17:14:51 -0800922 * nla_get_le16 - return payload of __le16 attribute
923 * @nla: __le16 netlink attribute
924 */
Patrick McHardyb057efd2008-10-28 11:59:11 -0700925static inline __le16 nla_get_le16(const struct nlattr *nla)
Thomas Graf4a89c252006-11-24 17:14:51 -0800926{
927 return *(__le16 *) nla_data(nla);
928}
929
930/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100931 * nla_get_u8 - return payload of u8 attribute
932 * @nla: u8 netlink attribute
933 */
Patrick McHardyb057efd2008-10-28 11:59:11 -0700934static inline u8 nla_get_u8(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100935{
936 return *(u8 *) nla_data(nla);
937}
938
939/**
940 * nla_get_u64 - return payload of u64 attribute
941 * @nla: u64 netlink attribute
942 */
Patrick McHardyb057efd2008-10-28 11:59:11 -0700943static inline u64 nla_get_u64(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100944{
945 u64 tmp;
946
947 nla_memcpy(&tmp, nla, sizeof(tmp));
948
949 return tmp;
950}
951
952/**
Pablo Neira Ayusoa17c8592009-05-27 17:50:35 +0200953 * nla_get_be64 - return payload of __be64 attribute
954 * @nla: __be64 netlink attribute
955 */
956static inline __be64 nla_get_be64(const struct nlattr *nla)
957{
Pablo Neira Ayusof5d410f2010-03-16 13:30:44 +0000958 __be64 tmp;
959
960 nla_memcpy(&tmp, nla, sizeof(tmp));
961
962 return tmp;
Pablo Neira Ayusoa17c8592009-05-27 17:50:35 +0200963}
964
965/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100966 * nla_get_flag - return payload of flag attribute
967 * @nla: flag netlink attribute
968 */
Patrick McHardyb057efd2008-10-28 11:59:11 -0700969static inline int nla_get_flag(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100970{
971 return !!nla;
972}
973
974/**
975 * nla_get_msecs - return payload of msecs attribute
976 * @nla: msecs netlink attribute
977 *
978 * Returns the number of milliseconds in jiffies.
979 */
Patrick McHardyb057efd2008-10-28 11:59:11 -0700980static inline unsigned long nla_get_msecs(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100981{
982 u64 msecs = nla_get_u64(nla);
983
984 return msecs_to_jiffies((unsigned long) msecs);
985}
986
987/**
988 * nla_nest_start - Start a new level of nested attributes
989 * @skb: socket buffer to add attributes to
990 * @attrtype: attribute type of container
991 *
992 * Returns the container attribute
993 */
994static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
995{
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700996 struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100997
998 if (nla_put(skb, attrtype, 0, NULL) < 0)
999 return NULL;
1000
1001 return start;
1002}
1003
1004/**
1005 * nla_nest_end - Finalize nesting of attributes
Pierre Ynardd1ec3b72007-10-10 21:09:48 -07001006 * @skb: socket buffer the attributes are stored in
Thomas Grafbfa83a92005-11-10 02:25:51 +01001007 * @start: container attribute
1008 *
1009 * Corrects the container attribute header to include the all
1010 * appeneded attributes.
1011 *
1012 * Returns the total data length of the skb.
1013 */
1014static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start)
1015{
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07001016 start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start;
Thomas Grafbfa83a92005-11-10 02:25:51 +01001017 return skb->len;
1018}
1019
1020/**
1021 * nla_nest_cancel - Cancel nesting of attributes
1022 * @skb: socket buffer the message is stored in
1023 * @start: container attribute
1024 *
1025 * Removes the container attribute and including all nested
Thomas Grafbc3ed282008-06-03 16:36:54 -07001026 * attributes. Returns -EMSGSIZE
Thomas Grafbfa83a92005-11-10 02:25:51 +01001027 */
Thomas Grafbc3ed282008-06-03 16:36:54 -07001028static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start)
Thomas Grafbfa83a92005-11-10 02:25:51 +01001029{
Thomas Grafbc3ed282008-06-03 16:36:54 -07001030 nlmsg_trim(skb, start);
Thomas Grafbfa83a92005-11-10 02:25:51 +01001031}
1032
1033/**
Paul Moore4fe5d5c2006-09-25 15:54:03 -07001034 * nla_validate_nested - Validate a stream of nested attributes
1035 * @start: container attribute
1036 * @maxtype: maximum attribute type to be expected
1037 * @policy: validation policy
1038 *
1039 * Validates all attributes in the nested attribute stream against the
1040 * specified policy. Attributes with a type exceeding maxtype will be
1041 * ignored. See documenation of struct nla_policy for more details.
1042 *
1043 * Returns 0 on success or a negative error code.
1044 */
Jan Engelhardt36546542010-11-16 09:52:32 -08001045static inline int nla_validate_nested(const struct nlattr *start, int maxtype,
Patrick McHardyef7c79e2007-06-05 12:38:30 -07001046 const struct nla_policy *policy)
Paul Moore4fe5d5c2006-09-25 15:54:03 -07001047{
1048 return nla_validate(nla_data(start), nla_len(start), maxtype, policy);
1049}
1050
1051/**
Thomas Grafbfa83a92005-11-10 02:25:51 +01001052 * nla_for_each_attr - iterate over a stream of attributes
1053 * @pos: loop counter, set to current attribute
1054 * @head: head of attribute stream
1055 * @len: length of attribute stream
1056 * @rem: initialized to len, holds bytes currently remaining in stream
1057 */
1058#define nla_for_each_attr(pos, head, len, rem) \
1059 for (pos = head, rem = len; \
1060 nla_ok(pos, rem); \
1061 pos = nla_next(pos, &(rem)))
1062
Thomas Graffe4944e2006-08-04 23:03:05 -07001063/**
1064 * nla_for_each_nested - iterate over nested attributes
1065 * @pos: loop counter, set to current attribute
1066 * @nla: attribute containing the nested attributes
1067 * @rem: initialized to len, holds bytes currently remaining in stream
1068 */
1069#define nla_for_each_nested(pos, nla, rem) \
1070 nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)
1071
Thomas Grafbfa83a92005-11-10 02:25:51 +01001072#endif