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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
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()
38 * nlmsg_end() finalize netlink message
39 * nlmsg_get_pos() return current position in message
40 * nlmsg_trim() trim part of message
41 * 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
47 * nlmsg_notify() send notification message
48 *
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 *
69 * Misc:
70 * nlmsg_report() report back to application?
71 *
72 * ------------------------------------------------------------------------
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:
87 * struct nlattr netlink attribute header
88 *
89 * Attribute Construction:
90 * nla_reserve(skb, type, len) reserve room for an attribute
91 * nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr
92 * nla_put(skb, type, len, data) add attribute to skb
93 * nla_put_nohdr(skb, len, data) add attribute w/o hdr
94 * nla_append(skb, len, data) append data to skb
95 *
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
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 */
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,
174 NLA_NESTED_COMPAT,
175 NLA_NUL_STRING,
176 NLA_BINARY,
177 __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
185 * @len: Type specific length of payload
186 *
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 *
190 * 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
194 * NLA_BINARY Maximum length of attribute payload
195 * NLA_NESTED_COMPAT Exact length of structure payload
196 * All other Exact length of attribute payload
197 *
198 * Example:
199 * static const struct nla_policy my_policy[ATTR_MAX+1] = {
200 * [ATTR_FOO] = { .type = NLA_U16 },
201 * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ },
202 * [ATTR_BAZ] = { .len = sizeof(struct mystruct) },
203 * };
204 */
205struct nla_policy {
206 u16 type;
207 u16 len;
208};
209
210/**
211 * struct nl_info - netlink source information
212 * @nlh: Netlink message header of original request
213 * @pid: Netlink PID of requesting application
214 */
215struct nl_info {
216 struct nlmsghdr *nlh;
217 struct net *nl_net;
218 u32 pid;
219};
220
221extern int netlink_rcv_skb(struct sk_buff *skb,
222 int (*cb)(struct sk_buff *,
223 struct nlmsghdr *));
224extern int nlmsg_notify(struct sock *sk, struct sk_buff *skb,
225 u32 pid, unsigned int group, int report,
226 gfp_t flags);
227
228extern int nla_validate(const struct nlattr *head,
229 int len, int maxtype,
230 const struct nla_policy *policy);
231extern int nla_parse(struct nlattr **tb, int maxtype,
232 const struct nlattr *head, int len,
233 const struct nla_policy *policy);
234extern int nla_policy_len(const struct nla_policy *, int);
235extern struct nlattr * nla_find(const struct nlattr *head,
236 int len, int attrtype);
237extern size_t nla_strlcpy(char *dst, const struct nlattr *nla,
238 size_t dstsize);
239extern int nla_memcpy(void *dest, const struct nlattr *src, int count);
240extern int nla_memcmp(const struct nlattr *nla, const void *data,
241 size_t size);
242extern int nla_strcmp(const struct nlattr *nla, const char *str);
243extern struct nlattr * __nla_reserve(struct sk_buff *skb, int attrtype,
244 int attrlen);
245extern void * __nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
246extern struct nlattr * nla_reserve(struct sk_buff *skb, int attrtype,
247 int attrlen);
248extern void * nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
249extern void __nla_put(struct sk_buff *skb, int attrtype,
250 int attrlen, const void *data);
251extern void __nla_put_nohdr(struct sk_buff *skb, int attrlen,
252 const void *data);
253extern int nla_put(struct sk_buff *skb, int attrtype,
254 int attrlen, const void *data);
255extern int nla_put_nohdr(struct sk_buff *skb, int attrlen,
256 const void *data);
257extern int nla_append(struct sk_buff *skb, int attrlen,
258 const void *data);
259
260/**************************************************************************
261 * Netlink Messages
262 **************************************************************************/
263
264/**
265 * nlmsg_msg_size - length of netlink message not including padding
266 * @payload: length of message payload
267 */
268static inline int nlmsg_msg_size(int payload)
269{
270 return NLMSG_HDRLEN + payload;
271}
272
273/**
274 * nlmsg_total_size - length of netlink message including padding
275 * @payload: length of message payload
276 */
277static inline int nlmsg_total_size(int payload)
278{
279 return NLMSG_ALIGN(nlmsg_msg_size(payload));
280}
281
282/**
283 * nlmsg_padlen - length of padding at the message's tail
284 * @payload: length of message payload
285 */
286static inline int nlmsg_padlen(int payload)
287{
288 return nlmsg_total_size(payload) - nlmsg_msg_size(payload);
289}
290
291/**
292 * nlmsg_data - head of message payload
293 * @nlh: netlink message header
294 */
295static inline void *nlmsg_data(const struct nlmsghdr *nlh)
296{
297 return (unsigned char *) nlh + NLMSG_HDRLEN;
298}
299
300/**
301 * nlmsg_len - length of message payload
302 * @nlh: netlink message header
303 */
304static inline int nlmsg_len(const struct nlmsghdr *nlh)
305{
306 return nlh->nlmsg_len - NLMSG_HDRLEN;
307}
308
309/**
310 * nlmsg_attrdata - head of attributes data
311 * @nlh: netlink message header
312 * @hdrlen: length of family specific header
313 */
314static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh,
315 int hdrlen)
316{
317 unsigned char *data = nlmsg_data(nlh);
318 return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen));
319}
320
321/**
322 * nlmsg_attrlen - length of attributes data
323 * @nlh: netlink message header
324 * @hdrlen: length of family specific header
325 */
326static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen)
327{
328 return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen);
329}
330
331/**
332 * nlmsg_ok - check if the netlink message fits into the remaining bytes
333 * @nlh: netlink message header
334 * @remaining: number of bytes remaining in message stream
335 */
336static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining)
337{
338 return (remaining >= (int) sizeof(struct nlmsghdr) &&
339 nlh->nlmsg_len >= sizeof(struct nlmsghdr) &&
340 nlh->nlmsg_len <= remaining);
341}
342
343/**
344 * nlmsg_next - next netlink message in message stream
345 * @nlh: netlink message header
346 * @remaining: number of bytes remaining in message stream
347 *
348 * Returns the next netlink message in the message stream and
349 * decrements remaining by the size of the current message.
350 */
351static inline struct nlmsghdr *
352nlmsg_next(const struct nlmsghdr *nlh, int *remaining)
353{
354 int totlen = NLMSG_ALIGN(nlh->nlmsg_len);
355
356 *remaining -= totlen;
357
358 return (struct nlmsghdr *) ((unsigned char *) nlh + totlen);
359}
360
361/**
362 * nlmsg_parse - parse attributes of a netlink message
363 * @nlh: netlink message header
364 * @hdrlen: length of family specific header
365 * @tb: destination array with maxtype+1 elements
366 * @maxtype: maximum attribute type to be expected
367 * @policy: validation policy
368 *
369 * See nla_parse()
370 */
371static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen,
372 struct nlattr *tb[], int maxtype,
373 const struct nla_policy *policy)
374{
375 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
376 return -EINVAL;
377
378 return nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen),
379 nlmsg_attrlen(nlh, hdrlen), policy);
380}
381
382/**
383 * nlmsg_find_attr - find a specific attribute in a netlink message
384 * @nlh: netlink message header
385 * @hdrlen: length of familiy specific header
386 * @attrtype: type of attribute to look for
387 *
388 * Returns the first attribute which matches the specified type.
389 */
390static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh,
391 int hdrlen, int attrtype)
392{
393 return nla_find(nlmsg_attrdata(nlh, hdrlen),
394 nlmsg_attrlen(nlh, hdrlen), attrtype);
395}
396
397/**
398 * nlmsg_validate - validate a netlink message including attributes
399 * @nlh: netlinket message header
400 * @hdrlen: length of familiy specific header
401 * @maxtype: maximum attribute type to be expected
402 * @policy: validation policy
403 */
404static inline int nlmsg_validate(const struct nlmsghdr *nlh,
405 int hdrlen, int maxtype,
406 const struct nla_policy *policy)
407{
408 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
409 return -EINVAL;
410
411 return nla_validate(nlmsg_attrdata(nlh, hdrlen),
412 nlmsg_attrlen(nlh, hdrlen), maxtype, policy);
413}
414
415/**
416 * nlmsg_report - need to report back to application?
417 * @nlh: netlink message header
418 *
419 * Returns 1 if a report back to the application is requested.
420 */
421static inline int nlmsg_report(const struct nlmsghdr *nlh)
422{
423 return !!(nlh->nlmsg_flags & NLM_F_ECHO);
424}
425
426/**
427 * nlmsg_for_each_attr - iterate over a stream of attributes
428 * @pos: loop counter, set to current attribute
429 * @nlh: netlink message header
430 * @hdrlen: length of familiy specific header
431 * @rem: initialized to len, holds bytes currently remaining in stream
432 */
433#define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \
434 nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \
435 nlmsg_attrlen(nlh, hdrlen), rem)
436
437#if 0
438/* FIXME: Enable once all users have been converted */
439
440/**
441 * __nlmsg_put - Add a new netlink message to an skb
442 * @skb: socket buffer to store message in
443 * @pid: netlink process id
444 * @seq: sequence number of message
445 * @type: message type
446 * @payload: length of message payload
447 * @flags: message flags
448 *
449 * The caller is responsible to ensure that the skb provides enough
450 * tailroom for both the netlink header and payload.
451 */
452static inline struct nlmsghdr *__nlmsg_put(struct sk_buff *skb, u32 pid,
453 u32 seq, int type, int payload,
454 int flags)
455{
456 struct nlmsghdr *nlh;
457
458 nlh = (struct nlmsghdr *) skb_put(skb, nlmsg_total_size(payload));
459 nlh->nlmsg_type = type;
460 nlh->nlmsg_len = nlmsg_msg_size(payload);
461 nlh->nlmsg_flags = flags;
462 nlh->nlmsg_pid = pid;
463 nlh->nlmsg_seq = seq;
464
465 memset((unsigned char *) nlmsg_data(nlh) + payload, 0,
466 nlmsg_padlen(payload));
467
468 return nlh;
469}
470#endif
471
472/**
473 * nlmsg_put - Add a new netlink message to an skb
474 * @skb: socket buffer to store message in
475 * @pid: netlink process id
476 * @seq: sequence number of message
477 * @type: message type
478 * @payload: length of message payload
479 * @flags: message flags
480 *
481 * Returns NULL if the tailroom of the skb is insufficient to store
482 * the message header and payload.
483 */
484static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
485 int type, int payload, int flags)
486{
487 if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload)))
488 return NULL;
489
490 return __nlmsg_put(skb, pid, seq, type, payload, flags);
491}
492
493/**
494 * nlmsg_put_answer - Add a new callback based netlink message to an skb
495 * @skb: socket buffer to store message in
496 * @cb: netlink callback
497 * @type: message type
498 * @payload: length of message payload
499 * @flags: message flags
500 *
501 * Returns NULL if the tailroom of the skb is insufficient to store
502 * the message header and payload.
503 */
504static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb,
505 struct netlink_callback *cb,
506 int type, int payload,
507 int flags)
508{
509 return nlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
510 type, payload, flags);
511}
512
513/**
514 * nlmsg_new - Allocate a new netlink message
515 * @payload: size of the message payload
516 * @flags: the type of memory to allocate.
517 *
518 * Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known
519 * and a good default is needed.
520 */
521static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags)
522{
523 return alloc_skb(nlmsg_total_size(payload), flags);
524}
525
526/**
527 * nlmsg_end - Finalize a netlink message
528 * @skb: socket buffer the message is stored in
529 * @nlh: netlink message header
530 *
531 * Corrects the netlink message header to include the appeneded
532 * attributes. Only necessary if attributes have been added to
533 * the message.
534 *
535 * Returns the total data length of the skb.
536 */
537static inline int nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh)
538{
539 nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh;
540
541 return skb->len;
542}
543
544/**
545 * nlmsg_get_pos - return current position in netlink message
546 * @skb: socket buffer the message is stored in
547 *
548 * Returns a pointer to the current tail of the message.
549 */
550static inline void *nlmsg_get_pos(struct sk_buff *skb)
551{
552 return skb_tail_pointer(skb);
553}
554
555/**
556 * nlmsg_trim - Trim message to a mark
557 * @skb: socket buffer the message is stored in
558 * @mark: mark to trim to
559 *
560 * Trims the message to the provided mark.
561 */
562static inline void nlmsg_trim(struct sk_buff *skb, const void *mark)
563{
564 if (mark)
565 skb_trim(skb, (unsigned char *) mark - skb->data);
566}
567
568/**
569 * nlmsg_cancel - Cancel construction of a netlink message
570 * @skb: socket buffer the message is stored in
571 * @nlh: netlink message header
572 *
573 * Removes the complete netlink message including all
574 * attributes from the socket buffer again.
575 */
576static inline void nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh)
577{
578 nlmsg_trim(skb, nlh);
579}
580
581/**
582 * nlmsg_free - free a netlink message
583 * @skb: socket buffer of netlink message
584 */
585static inline void nlmsg_free(struct sk_buff *skb)
586{
587 kfree_skb(skb);
588}
589
590/**
591 * nlmsg_multicast - multicast a netlink message
592 * @sk: netlink socket to spread messages to
593 * @skb: netlink message as socket buffer
594 * @pid: own netlink pid to avoid sending to yourself
595 * @group: multicast group id
596 * @flags: allocation flags
597 */
598static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb,
599 u32 pid, unsigned int group, gfp_t flags)
600{
601 int err;
602
603 NETLINK_CB(skb).dst_group = group;
604
605 err = netlink_broadcast(sk, skb, pid, group, flags);
606 if (err > 0)
607 err = 0;
608
609 return err;
610}
611
612/**
613 * nlmsg_unicast - unicast a netlink message
614 * @sk: netlink socket to spread message to
615 * @skb: netlink message as socket buffer
616 * @pid: netlink pid of the destination socket
617 */
618static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 pid)
619{
620 int err;
621
622 err = netlink_unicast(sk, skb, pid, MSG_DONTWAIT);
623 if (err > 0)
624 err = 0;
625
626 return err;
627}
628
629/**
630 * nlmsg_for_each_msg - iterate over a stream of messages
631 * @pos: loop counter, set to current message
632 * @head: head of message stream
633 * @len: length of message stream
634 * @rem: initialized to len, holds bytes currently remaining in stream
635 */
636#define nlmsg_for_each_msg(pos, head, len, rem) \
637 for (pos = head, rem = len; \
638 nlmsg_ok(pos, rem); \
639 pos = nlmsg_next(pos, &(rem)))
640
641/**
642 * nl_dump_check_consistent - check if sequence is consistent and advertise if not
643 * @cb: netlink callback structure that stores the sequence number
644 * @nlh: netlink message header to write the flag to
645 *
646 * This function checks if the sequence (generation) number changed during dump
647 * and if it did, advertises it in the netlink message header.
648 *
649 * The correct way to use it is to set cb->seq to the generation counter when
650 * all locks for dumping have been acquired, and then call this function for
651 * each message that is generated.
652 *
653 * Note that due to initialisation concerns, 0 is an invalid sequence number
654 * and must not be used by code that uses this functionality.
655 */
656static inline void
657nl_dump_check_consistent(struct netlink_callback *cb,
658 struct nlmsghdr *nlh)
659{
660 if (cb->prev_seq && cb->seq != cb->prev_seq)
661 nlh->nlmsg_flags |= NLM_F_DUMP_INTR;
662 cb->prev_seq = cb->seq;
663}
664
665/**************************************************************************
666 * Netlink Attributes
667 **************************************************************************/
668
669/**
670 * nla_attr_size - length of attribute not including padding
671 * @payload: length of payload
672 */
673static inline int nla_attr_size(int payload)
674{
675 return NLA_HDRLEN + payload;
676}
677
678/**
679 * nla_total_size - total length of attribute including padding
680 * @payload: length of payload
681 */
682static inline int nla_total_size(int payload)
683{
684 return NLA_ALIGN(nla_attr_size(payload));
685}
686
687/**
688 * nla_padlen - length of padding at the tail of attribute
689 * @payload: length of payload
690 */
691static inline int nla_padlen(int payload)
692{
693 return nla_total_size(payload) - nla_attr_size(payload);
694}
695
696/**
697 * nla_type - attribute type
698 * @nla: netlink attribute
699 */
700static inline int nla_type(const struct nlattr *nla)
701{
702 return nla->nla_type & NLA_TYPE_MASK;
703}
704
705/**
706 * nla_data - head of payload
707 * @nla: netlink attribute
708 */
709static inline void *nla_data(const struct nlattr *nla)
710{
711 return (char *) nla + NLA_HDRLEN;
712}
713
714/**
715 * nla_len - length of payload
716 * @nla: netlink attribute
717 */
718static inline int nla_len(const struct nlattr *nla)
719{
720 return nla->nla_len - NLA_HDRLEN;
721}
722
723/**
724 * nla_ok - check if the netlink attribute fits into the remaining bytes
725 * @nla: netlink attribute
726 * @remaining: number of bytes remaining in attribute stream
727 */
728static inline int nla_ok(const struct nlattr *nla, int remaining)
729{
730 return remaining >= (int) sizeof(*nla) &&
731 nla->nla_len >= sizeof(*nla) &&
732 nla->nla_len <= remaining;
733}
734
735/**
736 * nla_next - next netlink attribute in attribute stream
737 * @nla: netlink attribute
738 * @remaining: number of bytes remaining in attribute stream
739 *
740 * Returns the next netlink attribute in the attribute stream and
741 * decrements remaining by the size of the current attribute.
742 */
743static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining)
744{
745 int totlen = NLA_ALIGN(nla->nla_len);
746
747 *remaining -= totlen;
748 return (struct nlattr *) ((char *) nla + totlen);
749}
750
751/**
752 * nla_find_nested - find attribute in a set of nested attributes
753 * @nla: attribute containing the nested attributes
754 * @attrtype: type of attribute to look for
755 *
756 * Returns the first attribute which matches the specified type.
757 */
758static inline struct nlattr *
759nla_find_nested(const struct nlattr *nla, int attrtype)
760{
761 return nla_find(nla_data(nla), nla_len(nla), attrtype);
762}
763
764/**
765 * nla_parse_nested - parse nested attributes
766 * @tb: destination array with maxtype+1 elements
767 * @maxtype: maximum attribute type to be expected
768 * @nla: attribute containing the nested attributes
769 * @policy: validation policy
770 *
771 * See nla_parse()
772 */
773static inline int nla_parse_nested(struct nlattr *tb[], int maxtype,
774 const struct nlattr *nla,
775 const struct nla_policy *policy)
776{
777 return nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy);
778}
779
780/**
781 * nla_put_u8 - Add a u8 netlink attribute to a socket buffer
782 * @skb: socket buffer to add attribute to
783 * @attrtype: attribute type
784 * @value: numeric value
785 */
786static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value)
787{
788 return nla_put(skb, attrtype, sizeof(u8), &value);
789}
790
791/**
792 * nla_put_u16 - Add a u16 netlink attribute to a socket buffer
793 * @skb: socket buffer to add attribute to
794 * @attrtype: attribute type
795 * @value: numeric value
796 */
797static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value)
798{
799 return nla_put(skb, attrtype, sizeof(u16), &value);
800}
801
802/**
803 * nla_put_u32 - Add a u32 netlink attribute to a socket buffer
804 * @skb: socket buffer to add attribute to
805 * @attrtype: attribute type
806 * @value: numeric value
807 */
808static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value)
809{
810 return nla_put(skb, attrtype, sizeof(u32), &value);
811}
812
813/**
814 * nla_put_64 - Add a u64 netlink attribute to a socket buffer
815 * @skb: socket buffer to add attribute to
816 * @attrtype: attribute type
817 * @value: numeric value
818 */
819static inline int nla_put_u64(struct sk_buff *skb, int attrtype, u64 value)
820{
821 return nla_put(skb, attrtype, sizeof(u64), &value);
822}
823
824/**
825 * nla_put_string - Add a string netlink attribute to a socket buffer
826 * @skb: socket buffer to add attribute to
827 * @attrtype: attribute type
828 * @str: NUL terminated string
829 */
830static inline int nla_put_string(struct sk_buff *skb, int attrtype,
831 const char *str)
832{
833 return nla_put(skb, attrtype, strlen(str) + 1, str);
834}
835
836/**
837 * nla_put_flag - Add a flag netlink attribute to a socket buffer
838 * @skb: socket buffer to add attribute to
839 * @attrtype: attribute type
840 */
841static inline int nla_put_flag(struct sk_buff *skb, int attrtype)
842{
843 return nla_put(skb, attrtype, 0, NULL);
844}
845
846/**
847 * nla_put_msecs - Add a msecs netlink attribute to a socket buffer
848 * @skb: socket buffer to add attribute to
849 * @attrtype: attribute type
850 * @jiffies: number of msecs in jiffies
851 */
852static inline int nla_put_msecs(struct sk_buff *skb, int attrtype,
853 unsigned long jiffies)
854{
855 u64 tmp = jiffies_to_msecs(jiffies);
856 return nla_put(skb, attrtype, sizeof(u64), &tmp);
857}
858
859#define NLA_PUT(skb, attrtype, attrlen, data) \
860 do { \
861 if (unlikely(nla_put(skb, attrtype, attrlen, data) < 0)) \
862 goto nla_put_failure; \
863 } while(0)
864
865#define NLA_PUT_TYPE(skb, type, attrtype, value) \
866 do { \
867 type __tmp = value; \
868 NLA_PUT(skb, attrtype, sizeof(type), &__tmp); \
869 } while(0)
870
871#define NLA_PUT_U8(skb, attrtype, value) \
872 NLA_PUT_TYPE(skb, u8, attrtype, value)
873
874#define NLA_PUT_U16(skb, attrtype, value) \
875 NLA_PUT_TYPE(skb, u16, attrtype, value)
876
877#define NLA_PUT_LE16(skb, attrtype, value) \
878 NLA_PUT_TYPE(skb, __le16, attrtype, value)
879
880#define NLA_PUT_BE16(skb, attrtype, value) \
881 NLA_PUT_TYPE(skb, __be16, attrtype, value)
882
883#define NLA_PUT_NET16(skb, attrtype, value) \
884 NLA_PUT_BE16(skb, attrtype | NLA_F_NET_BYTEORDER, value)
885
886#define NLA_PUT_U32(skb, attrtype, value) \
887 NLA_PUT_TYPE(skb, u32, attrtype, value)
888
889#define NLA_PUT_BE32(skb, attrtype, value) \
890 NLA_PUT_TYPE(skb, __be32, attrtype, value)
891
892#define NLA_PUT_NET32(skb, attrtype, value) \
893 NLA_PUT_BE32(skb, attrtype | NLA_F_NET_BYTEORDER, value)
894
895#define NLA_PUT_U64(skb, attrtype, value) \
896 NLA_PUT_TYPE(skb, u64, attrtype, value)
897
898#define NLA_PUT_BE64(skb, attrtype, value) \
899 NLA_PUT_TYPE(skb, __be64, attrtype, value)
900
901#define NLA_PUT_NET64(skb, attrtype, value) \
902 NLA_PUT_BE64(skb, attrtype | NLA_F_NET_BYTEORDER, value)
903
904#define NLA_PUT_STRING(skb, attrtype, value) \
905 NLA_PUT(skb, attrtype, strlen(value) + 1, value)
906
907#define NLA_PUT_FLAG(skb, attrtype) \
908 NLA_PUT(skb, attrtype, 0, NULL)
909
910#define NLA_PUT_MSECS(skb, attrtype, jiffies) \
911 NLA_PUT_U64(skb, attrtype, jiffies_to_msecs(jiffies))
912
913/**
914 * nla_get_u32 - return payload of u32 attribute
915 * @nla: u32 netlink attribute
916 */
917static inline u32 nla_get_u32(const struct nlattr *nla)
918{
919 return *(u32 *) nla_data(nla);
920}
921
922/**
923 * nla_get_be32 - return payload of __be32 attribute
924 * @nla: __be32 netlink attribute
925 */
926static inline __be32 nla_get_be32(const struct nlattr *nla)
927{
928 return *(__be32 *) nla_data(nla);
929}
930
931/**
932 * nla_get_u16 - return payload of u16 attribute
933 * @nla: u16 netlink attribute
934 */
935static inline u16 nla_get_u16(const struct nlattr *nla)
936{
937 return *(u16 *) nla_data(nla);
938}
939
940/**
941 * nla_get_be16 - return payload of __be16 attribute
942 * @nla: __be16 netlink attribute
943 */
944static inline __be16 nla_get_be16(const struct nlattr *nla)
945{
946 return *(__be16 *) nla_data(nla);
947}
948
949/**
950 * nla_get_le16 - return payload of __le16 attribute
951 * @nla: __le16 netlink attribute
952 */
953static inline __le16 nla_get_le16(const struct nlattr *nla)
954{
955 return *(__le16 *) nla_data(nla);
956}
957
958/**
959 * nla_get_u8 - return payload of u8 attribute
960 * @nla: u8 netlink attribute
961 */
962static inline u8 nla_get_u8(const struct nlattr *nla)
963{
964 return *(u8 *) nla_data(nla);
965}
966
967/**
968 * nla_get_u64 - return payload of u64 attribute
969 * @nla: u64 netlink attribute
970 */
971static inline u64 nla_get_u64(const struct nlattr *nla)
972{
973 u64 tmp;
974
975 nla_memcpy(&tmp, nla, sizeof(tmp));
976
977 return tmp;
978}
979
980/**
981 * nla_get_be64 - return payload of __be64 attribute
982 * @nla: __be64 netlink attribute
983 */
984static inline __be64 nla_get_be64(const struct nlattr *nla)
985{
986 __be64 tmp;
987
988 nla_memcpy(&tmp, nla, sizeof(tmp));
989
990 return tmp;
991}
992
993/**
994 * nla_get_flag - return payload of flag attribute
995 * @nla: flag netlink attribute
996 */
997static inline int nla_get_flag(const struct nlattr *nla)
998{
999 return !!nla;
1000}
1001
1002/**
1003 * nla_get_msecs - return payload of msecs attribute
1004 * @nla: msecs netlink attribute
1005 *
1006 * Returns the number of milliseconds in jiffies.
1007 */
1008static inline unsigned long nla_get_msecs(const struct nlattr *nla)
1009{
1010 u64 msecs = nla_get_u64(nla);
1011
1012 return msecs_to_jiffies((unsigned long) msecs);
1013}
1014
1015/**
1016 * nla_nest_start - Start a new level of nested attributes
1017 * @skb: socket buffer to add attributes to
1018 * @attrtype: attribute type of container
1019 *
1020 * Returns the container attribute
1021 */
1022static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
1023{
1024 struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb);
1025
1026 if (nla_put(skb, attrtype, 0, NULL) < 0)
1027 return NULL;
1028
1029 return start;
1030}
1031
1032/**
1033 * nla_nest_end - Finalize nesting of attributes
1034 * @skb: socket buffer the attributes are stored in
1035 * @start: container attribute
1036 *
1037 * Corrects the container attribute header to include the all
1038 * appeneded attributes.
1039 *
1040 * Returns the total data length of the skb.
1041 */
1042static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start)
1043{
1044 start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start;
1045 return skb->len;
1046}
1047
1048/**
1049 * nla_nest_cancel - Cancel nesting of attributes
1050 * @skb: socket buffer the message is stored in
1051 * @start: container attribute
1052 *
1053 * Removes the container attribute and including all nested
1054 * attributes. Returns -EMSGSIZE
1055 */
1056static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start)
1057{
1058 nlmsg_trim(skb, start);
1059}
1060
1061/**
1062 * nla_validate_nested - Validate a stream of nested attributes
1063 * @start: container attribute
1064 * @maxtype: maximum attribute type to be expected
1065 * @policy: validation policy
1066 *
1067 * Validates all attributes in the nested attribute stream against the
1068 * specified policy. Attributes with a type exceeding maxtype will be
1069 * ignored. See documenation of struct nla_policy for more details.
1070 *
1071 * Returns 0 on success or a negative error code.
1072 */
1073static inline int nla_validate_nested(const struct nlattr *start, int maxtype,
1074 const struct nla_policy *policy)
1075{
1076 return nla_validate(nla_data(start), nla_len(start), maxtype, policy);
1077}
1078
1079/**
1080 * nla_for_each_attr - iterate over a stream of attributes
1081 * @pos: loop counter, set to current attribute
1082 * @head: head of attribute stream
1083 * @len: length of attribute stream
1084 * @rem: initialized to len, holds bytes currently remaining in stream
1085 */
1086#define nla_for_each_attr(pos, head, len, rem) \
1087 for (pos = head, rem = len; \
1088 nla_ok(pos, rem); \
1089 pos = nla_next(pos, &(rem)))
1090
1091/**
1092 * nla_for_each_nested - iterate over nested attributes
1093 * @pos: loop counter, set to current attribute
1094 * @nla: attribute containing the nested attributes
1095 * @rem: initialized to len, holds bytes currently remaining in stream
1096 */
1097#define nla_for_each_nested(pos, nla, rem) \
1098 nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)
1099
1100#endif
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(skb, type, value) add u64 attribute to skb
102 * nla_put_s8(skb, type, value) add s8 attribute to skb
103 * nla_put_s16(skb, type, value) add s16 attribute to skb
104 * nla_put_s32(skb, type, value) add s32 attribute to skb
105 * nla_put_s64(skb, type, value) add s64 attribute to skb
106 * nla_put_string(skb, type, str) add string attribute to skb
107 * nla_put_flag(skb, type) add flag attribute to skb
108 * nla_put_msecs(skb, type, jiffies) add msecs attribute to skb
109 * nla_put_in_addr(skb, type, addr) add IPv4 address attribute to skb
110 * nla_put_in6_addr(skb, type, addr) add IPv6 address attribute to skb
111 *
112 * Nested Attributes Construction:
113 * nla_nest_start(skb, type) start a nested attribute
114 * nla_nest_end(skb, nla) finalize a nested attribute
115 * nla_nest_cancel(skb, nla) cancel nested attribute construction
116 *
117 * Attribute Length Calculations:
118 * nla_attr_size(payload) length of attribute w/o padding
119 * nla_total_size(payload) length of attribute w/ padding
120 * nla_padlen(payload) length of padding
121 *
122 * Attribute Payload Access:
123 * nla_data(nla) head of attribute payload
124 * nla_len(nla) length of attribute payload
125 *
126 * Attribute Payload Access for Basic Types:
127 * nla_get_u8(nla) get payload for a u8 attribute
128 * nla_get_u16(nla) get payload for a u16 attribute
129 * nla_get_u32(nla) get payload for a u32 attribute
130 * nla_get_u64(nla) get payload for a u64 attribute
131 * nla_get_s8(nla) get payload for a s8 attribute
132 * nla_get_s16(nla) get payload for a s16 attribute
133 * nla_get_s32(nla) get payload for a s32 attribute
134 * nla_get_s64(nla) get payload for a s64 attribute
135 * nla_get_flag(nla) return 1 if flag is true
136 * nla_get_msecs(nla) get payload for a msecs attribute
137 *
138 * Attribute Misc:
139 * nla_memcpy(dest, nla, count) copy attribute into memory
140 * nla_memcmp(nla, data, size) compare attribute with memory area
141 * nla_strlcpy(dst, nla, size) copy attribute to a sized string
142 * nla_strcmp(nla, str) compare attribute with string
143 *
144 * Attribute Parsing:
145 * nla_ok(nla, remaining) does nla fit into remaining bytes?
146 * nla_next(nla, remaining) get next netlink attribute
147 * nla_validate() validate a stream of attributes
148 * nla_validate_nested() validate a stream of nested attributes
149 * nla_find() find attribute in stream of attributes
150 * nla_find_nested() find attribute in nested attributes
151 * nla_parse() parse and validate stream of attrs
152 * nla_parse_nested() parse nested attribuets
153 * nla_for_each_attr() loop over all attributes
154 * nla_for_each_nested() loop over the nested attributes
155 *=========================================================================
156 */
157
158 /**
159 * Standard attribute types to specify validation policy
160 */
161enum {
162 NLA_UNSPEC,
163 NLA_U8,
164 NLA_U16,
165 NLA_U32,
166 NLA_U64,
167 NLA_STRING,
168 NLA_FLAG,
169 NLA_MSECS,
170 NLA_NESTED,
171 NLA_NESTED_COMPAT,
172 NLA_NUL_STRING,
173 NLA_BINARY,
174 NLA_S8,
175 NLA_S16,
176 NLA_S32,
177 NLA_S64,
178 __NLA_TYPE_MAX,
179};
180
181#define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1)
182
183/**
184 * struct nla_policy - attribute validation policy
185 * @type: Type of attribute or NLA_UNSPEC
186 * @len: Type specific length of payload
187 *
188 * Policies are defined as arrays of this struct, the array must be
189 * accessible by attribute type up to the highest identifier to be expected.
190 *
191 * Meaning of `len' field:
192 * NLA_STRING Maximum length of string
193 * NLA_NUL_STRING Maximum length of string (excluding NUL)
194 * NLA_FLAG Unused
195 * NLA_BINARY Maximum length of attribute payload
196 * NLA_NESTED Don't use `len' field -- length verification is
197 * done by checking len of nested header (or empty)
198 * NLA_NESTED_COMPAT Minimum length of structure payload
199 * NLA_U8, NLA_U16,
200 * NLA_U32, NLA_U64,
201 * NLA_S8, NLA_S16,
202 * NLA_S32, NLA_S64,
203 * NLA_MSECS Leaving the length field zero will verify the
204 * given type fits, using it verifies minimum length
205 * just like "All other"
206 * All other Minimum length of attribute payload
207 *
208 * Example:
209 * static const struct nla_policy my_policy[ATTR_MAX+1] = {
210 * [ATTR_FOO] = { .type = NLA_U16 },
211 * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ },
212 * [ATTR_BAZ] = { .len = sizeof(struct mystruct) },
213 * };
214 */
215struct nla_policy {
216 u16 type;
217 u16 len;
218};
219
220/**
221 * struct nl_info - netlink source information
222 * @nlh: Netlink message header of original request
223 * @portid: Netlink PORTID of requesting application
224 */
225struct nl_info {
226 struct nlmsghdr *nlh;
227 struct net *nl_net;
228 u32 portid;
229};
230
231int netlink_rcv_skb(struct sk_buff *skb,
232 int (*cb)(struct sk_buff *, struct nlmsghdr *));
233int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid,
234 unsigned int group, int report, gfp_t flags);
235
236int nla_validate(const struct nlattr *head, int len, int maxtype,
237 const struct nla_policy *policy);
238int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
239 int len, const struct nla_policy *policy);
240int nla_policy_len(const struct nla_policy *, int);
241struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype);
242size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize);
243int nla_memcpy(void *dest, const struct nlattr *src, int count);
244int nla_memcmp(const struct nlattr *nla, const void *data, size_t size);
245int nla_strcmp(const struct nlattr *nla, const char *str);
246struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen);
247void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
248struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen);
249void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
250void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
251 const void *data);
252void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data);
253int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data);
254int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data);
255int nla_append(struct sk_buff *skb, int attrlen, const void *data);
256
257/**************************************************************************
258 * Netlink Messages
259 **************************************************************************/
260
261/**
262 * nlmsg_msg_size - length of netlink message not including padding
263 * @payload: length of message payload
264 */
265static inline int nlmsg_msg_size(int payload)
266{
267 return NLMSG_HDRLEN + payload;
268}
269
270/**
271 * nlmsg_total_size - length of netlink message including padding
272 * @payload: length of message payload
273 */
274static inline int nlmsg_total_size(int payload)
275{
276 return NLMSG_ALIGN(nlmsg_msg_size(payload));
277}
278
279/**
280 * nlmsg_padlen - length of padding at the message's tail
281 * @payload: length of message payload
282 */
283static inline int nlmsg_padlen(int payload)
284{
285 return nlmsg_total_size(payload) - nlmsg_msg_size(payload);
286}
287
288/**
289 * nlmsg_data - head of message payload
290 * @nlh: netlink message header
291 */
292static inline void *nlmsg_data(const struct nlmsghdr *nlh)
293{
294 return (unsigned char *) nlh + NLMSG_HDRLEN;
295}
296
297/**
298 * nlmsg_len - length of message payload
299 * @nlh: netlink message header
300 */
301static inline int nlmsg_len(const struct nlmsghdr *nlh)
302{
303 return nlh->nlmsg_len - NLMSG_HDRLEN;
304}
305
306/**
307 * nlmsg_attrdata - head of attributes data
308 * @nlh: netlink message header
309 * @hdrlen: length of family specific header
310 */
311static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh,
312 int hdrlen)
313{
314 unsigned char *data = nlmsg_data(nlh);
315 return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen));
316}
317
318/**
319 * nlmsg_attrlen - length of attributes data
320 * @nlh: netlink message header
321 * @hdrlen: length of family specific header
322 */
323static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen)
324{
325 return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen);
326}
327
328/**
329 * nlmsg_ok - check if the netlink message fits into the remaining bytes
330 * @nlh: netlink message header
331 * @remaining: number of bytes remaining in message stream
332 */
333static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining)
334{
335 return (remaining >= (int) sizeof(struct nlmsghdr) &&
336 nlh->nlmsg_len >= sizeof(struct nlmsghdr) &&
337 nlh->nlmsg_len <= remaining);
338}
339
340/**
341 * nlmsg_next - next netlink message in message stream
342 * @nlh: netlink message header
343 * @remaining: number of bytes remaining in message stream
344 *
345 * Returns the next netlink message in the message stream and
346 * decrements remaining by the size of the current message.
347 */
348static inline struct nlmsghdr *
349nlmsg_next(const struct nlmsghdr *nlh, int *remaining)
350{
351 int totlen = NLMSG_ALIGN(nlh->nlmsg_len);
352
353 *remaining -= totlen;
354
355 return (struct nlmsghdr *) ((unsigned char *) nlh + totlen);
356}
357
358/**
359 * nlmsg_parse - parse attributes of a netlink message
360 * @nlh: netlink message header
361 * @hdrlen: length of family specific header
362 * @tb: destination array with maxtype+1 elements
363 * @maxtype: maximum attribute type to be expected
364 * @policy: validation policy
365 *
366 * See nla_parse()
367 */
368static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen,
369 struct nlattr *tb[], int maxtype,
370 const struct nla_policy *policy)
371{
372 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
373 return -EINVAL;
374
375 return nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen),
376 nlmsg_attrlen(nlh, hdrlen), policy);
377}
378
379/**
380 * nlmsg_find_attr - find a specific attribute in a netlink message
381 * @nlh: netlink message header
382 * @hdrlen: length of familiy specific header
383 * @attrtype: type of attribute to look for
384 *
385 * Returns the first attribute which matches the specified type.
386 */
387static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh,
388 int hdrlen, int attrtype)
389{
390 return nla_find(nlmsg_attrdata(nlh, hdrlen),
391 nlmsg_attrlen(nlh, hdrlen), attrtype);
392}
393
394/**
395 * nlmsg_validate - validate a netlink message including attributes
396 * @nlh: netlinket message header
397 * @hdrlen: length of familiy specific header
398 * @maxtype: maximum attribute type to be expected
399 * @policy: validation policy
400 */
401static inline int nlmsg_validate(const struct nlmsghdr *nlh,
402 int hdrlen, int maxtype,
403 const struct nla_policy *policy)
404{
405 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
406 return -EINVAL;
407
408 return nla_validate(nlmsg_attrdata(nlh, hdrlen),
409 nlmsg_attrlen(nlh, hdrlen), maxtype, policy);
410}
411
412/**
413 * nlmsg_report - need to report back to application?
414 * @nlh: netlink message header
415 *
416 * Returns 1 if a report back to the application is requested.
417 */
418static inline int nlmsg_report(const struct nlmsghdr *nlh)
419{
420 return !!(nlh->nlmsg_flags & NLM_F_ECHO);
421}
422
423/**
424 * nlmsg_for_each_attr - iterate over a stream of attributes
425 * @pos: loop counter, set to current attribute
426 * @nlh: netlink message header
427 * @hdrlen: length of familiy specific header
428 * @rem: initialized to len, holds bytes currently remaining in stream
429 */
430#define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \
431 nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \
432 nlmsg_attrlen(nlh, hdrlen), rem)
433
434/**
435 * nlmsg_put - Add a new netlink message to an skb
436 * @skb: socket buffer to store message in
437 * @portid: netlink PORTID of requesting application
438 * @seq: sequence number of message
439 * @type: message type
440 * @payload: length of message payload
441 * @flags: message flags
442 *
443 * Returns NULL if the tailroom of the skb is insufficient to store
444 * the message header and payload.
445 */
446static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
447 int type, int payload, int flags)
448{
449 if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload)))
450 return NULL;
451
452 return __nlmsg_put(skb, portid, seq, type, payload, flags);
453}
454
455/**
456 * nlmsg_put_answer - Add a new callback based netlink message to an skb
457 * @skb: socket buffer to store message in
458 * @cb: netlink callback
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 */
466static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb,
467 struct netlink_callback *cb,
468 int type, int payload,
469 int flags)
470{
471 return nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
472 type, payload, flags);
473}
474
475/**
476 * nlmsg_new - Allocate a new netlink message
477 * @payload: size of the message payload
478 * @flags: the type of memory to allocate.
479 *
480 * Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known
481 * and a good default is needed.
482 */
483static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags)
484{
485 return alloc_skb(nlmsg_total_size(payload), flags);
486}
487
488/**
489 * nlmsg_end - Finalize a netlink message
490 * @skb: socket buffer the message is stored in
491 * @nlh: netlink message header
492 *
493 * Corrects the netlink message header to include the appeneded
494 * attributes. Only necessary if attributes have been added to
495 * the message.
496 */
497static inline void nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh)
498{
499 nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh;
500}
501
502/**
503 * nlmsg_get_pos - return current position in netlink message
504 * @skb: socket buffer the message is stored in
505 *
506 * Returns a pointer to the current tail of the message.
507 */
508static inline void *nlmsg_get_pos(struct sk_buff *skb)
509{
510 return skb_tail_pointer(skb);
511}
512
513/**
514 * nlmsg_trim - Trim message to a mark
515 * @skb: socket buffer the message is stored in
516 * @mark: mark to trim to
517 *
518 * Trims the message to the provided mark.
519 */
520static inline void nlmsg_trim(struct sk_buff *skb, const void *mark)
521{
522 if (mark) {
523 WARN_ON((unsigned char *) mark < skb->data);
524 skb_trim(skb, (unsigned char *) mark - skb->data);
525 }
526}
527
528/**
529 * nlmsg_cancel - Cancel construction of a netlink message
530 * @skb: socket buffer the message is stored in
531 * @nlh: netlink message header
532 *
533 * Removes the complete netlink message including all
534 * attributes from the socket buffer again.
535 */
536static inline void nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh)
537{
538 nlmsg_trim(skb, nlh);
539}
540
541/**
542 * nlmsg_free - free a netlink message
543 * @skb: socket buffer of netlink message
544 */
545static inline void nlmsg_free(struct sk_buff *skb)
546{
547 kfree_skb(skb);
548}
549
550/**
551 * nlmsg_multicast - multicast a netlink message
552 * @sk: netlink socket to spread messages to
553 * @skb: netlink message as socket buffer
554 * @portid: own netlink portid to avoid sending to yourself
555 * @group: multicast group id
556 * @flags: allocation flags
557 */
558static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb,
559 u32 portid, unsigned int group, gfp_t flags)
560{
561 int err;
562
563 NETLINK_CB(skb).dst_group = group;
564
565 err = netlink_broadcast(sk, skb, portid, group, flags);
566 if (err > 0)
567 err = 0;
568
569 return err;
570}
571
572/**
573 * nlmsg_unicast - unicast a netlink message
574 * @sk: netlink socket to spread message to
575 * @skb: netlink message as socket buffer
576 * @portid: netlink portid of the destination socket
577 */
578static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 portid)
579{
580 int err;
581
582 err = netlink_unicast(sk, skb, portid, MSG_DONTWAIT);
583 if (err > 0)
584 err = 0;
585
586 return err;
587}
588
589/**
590 * nlmsg_for_each_msg - iterate over a stream of messages
591 * @pos: loop counter, set to current message
592 * @head: head of message stream
593 * @len: length of message stream
594 * @rem: initialized to len, holds bytes currently remaining in stream
595 */
596#define nlmsg_for_each_msg(pos, head, len, rem) \
597 for (pos = head, rem = len; \
598 nlmsg_ok(pos, rem); \
599 pos = nlmsg_next(pos, &(rem)))
600
601/**
602 * nl_dump_check_consistent - check if sequence is consistent and advertise if not
603 * @cb: netlink callback structure that stores the sequence number
604 * @nlh: netlink message header to write the flag to
605 *
606 * This function checks if the sequence (generation) number changed during dump
607 * and if it did, advertises it in the netlink message header.
608 *
609 * The correct way to use it is to set cb->seq to the generation counter when
610 * all locks for dumping have been acquired, and then call this function for
611 * each message that is generated.
612 *
613 * Note that due to initialisation concerns, 0 is an invalid sequence number
614 * and must not be used by code that uses this functionality.
615 */
616static inline void
617nl_dump_check_consistent(struct netlink_callback *cb,
618 struct nlmsghdr *nlh)
619{
620 if (cb->prev_seq && cb->seq != cb->prev_seq)
621 nlh->nlmsg_flags |= NLM_F_DUMP_INTR;
622 cb->prev_seq = cb->seq;
623}
624
625/**************************************************************************
626 * Netlink Attributes
627 **************************************************************************/
628
629/**
630 * nla_attr_size - length of attribute not including padding
631 * @payload: length of payload
632 */
633static inline int nla_attr_size(int payload)
634{
635 return NLA_HDRLEN + payload;
636}
637
638/**
639 * nla_total_size - total length of attribute including padding
640 * @payload: length of payload
641 */
642static inline int nla_total_size(int payload)
643{
644 return NLA_ALIGN(nla_attr_size(payload));
645}
646
647/**
648 * nla_padlen - length of padding at the tail of attribute
649 * @payload: length of payload
650 */
651static inline int nla_padlen(int payload)
652{
653 return nla_total_size(payload) - nla_attr_size(payload);
654}
655
656/**
657 * nla_type - attribute type
658 * @nla: netlink attribute
659 */
660static inline int nla_type(const struct nlattr *nla)
661{
662 return nla->nla_type & NLA_TYPE_MASK;
663}
664
665/**
666 * nla_data - head of payload
667 * @nla: netlink attribute
668 */
669static inline void *nla_data(const struct nlattr *nla)
670{
671 return (char *) nla + NLA_HDRLEN;
672}
673
674/**
675 * nla_len - length of payload
676 * @nla: netlink attribute
677 */
678static inline int nla_len(const struct nlattr *nla)
679{
680 return nla->nla_len - NLA_HDRLEN;
681}
682
683/**
684 * nla_ok - check if the netlink attribute fits into the remaining bytes
685 * @nla: netlink attribute
686 * @remaining: number of bytes remaining in attribute stream
687 */
688static inline int nla_ok(const struct nlattr *nla, int remaining)
689{
690 return remaining >= (int) sizeof(*nla) &&
691 nla->nla_len >= sizeof(*nla) &&
692 nla->nla_len <= remaining;
693}
694
695/**
696 * nla_next - next netlink attribute in attribute stream
697 * @nla: netlink attribute
698 * @remaining: number of bytes remaining in attribute stream
699 *
700 * Returns the next netlink attribute in the attribute stream and
701 * decrements remaining by the size of the current attribute.
702 */
703static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining)
704{
705 int totlen = NLA_ALIGN(nla->nla_len);
706
707 *remaining -= totlen;
708 return (struct nlattr *) ((char *) nla + totlen);
709}
710
711/**
712 * nla_find_nested - find attribute in a set of nested attributes
713 * @nla: attribute containing the nested attributes
714 * @attrtype: type of attribute to look for
715 *
716 * Returns the first attribute which matches the specified type.
717 */
718static inline struct nlattr *
719nla_find_nested(const struct nlattr *nla, int attrtype)
720{
721 return nla_find(nla_data(nla), nla_len(nla), attrtype);
722}
723
724/**
725 * nla_parse_nested - parse nested attributes
726 * @tb: destination array with maxtype+1 elements
727 * @maxtype: maximum attribute type to be expected
728 * @nla: attribute containing the nested attributes
729 * @policy: validation policy
730 *
731 * See nla_parse()
732 */
733static inline int nla_parse_nested(struct nlattr *tb[], int maxtype,
734 const struct nlattr *nla,
735 const struct nla_policy *policy)
736{
737 return nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy);
738}
739
740/**
741 * nla_put_u8 - Add a u8 netlink attribute to a socket buffer
742 * @skb: socket buffer to add attribute to
743 * @attrtype: attribute type
744 * @value: numeric value
745 */
746static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value)
747{
748 return nla_put(skb, attrtype, sizeof(u8), &value);
749}
750
751/**
752 * nla_put_u16 - Add a u16 netlink attribute to a socket buffer
753 * @skb: socket buffer to add attribute to
754 * @attrtype: attribute type
755 * @value: numeric value
756 */
757static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value)
758{
759 return nla_put(skb, attrtype, sizeof(u16), &value);
760}
761
762/**
763 * nla_put_be16 - Add a __be16 netlink attribute to a socket buffer
764 * @skb: socket buffer to add attribute to
765 * @attrtype: attribute type
766 * @value: numeric value
767 */
768static inline int nla_put_be16(struct sk_buff *skb, int attrtype, __be16 value)
769{
770 return nla_put(skb, attrtype, sizeof(__be16), &value);
771}
772
773/**
774 * nla_put_net16 - Add 16-bit network byte order netlink attribute to a socket buffer
775 * @skb: socket buffer to add attribute to
776 * @attrtype: attribute type
777 * @value: numeric value
778 */
779static inline int nla_put_net16(struct sk_buff *skb, int attrtype, __be16 value)
780{
781 return nla_put_be16(skb, attrtype | NLA_F_NET_BYTEORDER, value);
782}
783
784/**
785 * nla_put_le16 - Add a __le16 netlink attribute to a socket buffer
786 * @skb: socket buffer to add attribute to
787 * @attrtype: attribute type
788 * @value: numeric value
789 */
790static inline int nla_put_le16(struct sk_buff *skb, int attrtype, __le16 value)
791{
792 return nla_put(skb, attrtype, sizeof(__le16), &value);
793}
794
795/**
796 * nla_put_u32 - Add a u32 netlink attribute to a socket buffer
797 * @skb: socket buffer to add attribute to
798 * @attrtype: attribute type
799 * @value: numeric value
800 */
801static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value)
802{
803 return nla_put(skb, attrtype, sizeof(u32), &value);
804}
805
806/**
807 * nla_put_be32 - Add a __be32 netlink attribute to a socket buffer
808 * @skb: socket buffer to add attribute to
809 * @attrtype: attribute type
810 * @value: numeric value
811 */
812static inline int nla_put_be32(struct sk_buff *skb, int attrtype, __be32 value)
813{
814 return nla_put(skb, attrtype, sizeof(__be32), &value);
815}
816
817/**
818 * nla_put_net32 - Add 32-bit network byte order netlink attribute to a socket buffer
819 * @skb: socket buffer to add attribute to
820 * @attrtype: attribute type
821 * @value: numeric value
822 */
823static inline int nla_put_net32(struct sk_buff *skb, int attrtype, __be32 value)
824{
825 return nla_put_be32(skb, attrtype | NLA_F_NET_BYTEORDER, value);
826}
827
828/**
829 * nla_put_le32 - Add a __le32 netlink attribute to a socket buffer
830 * @skb: socket buffer to add attribute to
831 * @attrtype: attribute type
832 * @value: numeric value
833 */
834static inline int nla_put_le32(struct sk_buff *skb, int attrtype, __le32 value)
835{
836 return nla_put(skb, attrtype, sizeof(__le32), &value);
837}
838
839/**
840 * nla_put_u64 - Add a u64 netlink attribute to a socket buffer
841 * @skb: socket buffer to add attribute to
842 * @attrtype: attribute type
843 * @value: numeric value
844 */
845static inline int nla_put_u64(struct sk_buff *skb, int attrtype, u64 value)
846{
847 return nla_put(skb, attrtype, sizeof(u64), &value);
848}
849
850/**
851 * nla_put_be64 - Add a __be64 netlink attribute to a socket buffer
852 * @skb: socket buffer to add attribute to
853 * @attrtype: attribute type
854 * @value: numeric value
855 */
856static inline int nla_put_be64(struct sk_buff *skb, int attrtype, __be64 value)
857{
858 return nla_put(skb, attrtype, sizeof(__be64), &value);
859}
860
861/**
862 * nla_put_net64 - Add 64-bit network byte order netlink attribute to a socket buffer
863 * @skb: socket buffer to add attribute to
864 * @attrtype: attribute type
865 * @value: numeric value
866 */
867static inline int nla_put_net64(struct sk_buff *skb, int attrtype, __be64 value)
868{
869 return nla_put_be64(skb, attrtype | NLA_F_NET_BYTEORDER, value);
870}
871
872/**
873 * nla_put_le64 - Add a __le64 netlink attribute to a socket buffer
874 * @skb: socket buffer to add attribute to
875 * @attrtype: attribute type
876 * @value: numeric value
877 */
878static inline int nla_put_le64(struct sk_buff *skb, int attrtype, __le64 value)
879{
880 return nla_put(skb, attrtype, sizeof(__le64), &value);
881}
882
883/**
884 * nla_put_s8 - Add a s8 netlink attribute to a socket buffer
885 * @skb: socket buffer to add attribute to
886 * @attrtype: attribute type
887 * @value: numeric value
888 */
889static inline int nla_put_s8(struct sk_buff *skb, int attrtype, s8 value)
890{
891 return nla_put(skb, attrtype, sizeof(s8), &value);
892}
893
894/**
895 * nla_put_s16 - Add a s16 netlink attribute to a socket buffer
896 * @skb: socket buffer to add attribute to
897 * @attrtype: attribute type
898 * @value: numeric value
899 */
900static inline int nla_put_s16(struct sk_buff *skb, int attrtype, s16 value)
901{
902 return nla_put(skb, attrtype, sizeof(s16), &value);
903}
904
905/**
906 * nla_put_s32 - Add a s32 netlink attribute to a socket buffer
907 * @skb: socket buffer to add attribute to
908 * @attrtype: attribute type
909 * @value: numeric value
910 */
911static inline int nla_put_s32(struct sk_buff *skb, int attrtype, s32 value)
912{
913 return nla_put(skb, attrtype, sizeof(s32), &value);
914}
915
916/**
917 * nla_put_s64 - Add a s64 netlink attribute to a socket buffer
918 * @skb: socket buffer to add attribute to
919 * @attrtype: attribute type
920 * @value: numeric value
921 */
922static inline int nla_put_s64(struct sk_buff *skb, int attrtype, s64 value)
923{
924 return nla_put(skb, attrtype, sizeof(s64), &value);
925}
926
927/**
928 * nla_put_string - Add a string netlink attribute to a socket buffer
929 * @skb: socket buffer to add attribute to
930 * @attrtype: attribute type
931 * @str: NUL terminated string
932 */
933static inline int nla_put_string(struct sk_buff *skb, int attrtype,
934 const char *str)
935{
936 return nla_put(skb, attrtype, strlen(str) + 1, str);
937}
938
939/**
940 * nla_put_flag - Add a flag netlink attribute to a socket buffer
941 * @skb: socket buffer to add attribute to
942 * @attrtype: attribute type
943 */
944static inline int nla_put_flag(struct sk_buff *skb, int attrtype)
945{
946 return nla_put(skb, attrtype, 0, NULL);
947}
948
949/**
950 * nla_put_msecs - Add a msecs netlink attribute to a socket buffer
951 * @skb: socket buffer to add attribute to
952 * @attrtype: attribute type
953 * @njiffies: number of jiffies to convert to msecs
954 */
955static inline int nla_put_msecs(struct sk_buff *skb, int attrtype,
956 unsigned long njiffies)
957{
958 u64 tmp = jiffies_to_msecs(njiffies);
959 return nla_put(skb, attrtype, sizeof(u64), &tmp);
960}
961
962/**
963 * nla_put_in_addr - Add an IPv4 address netlink attribute to a socket
964 * buffer
965 * @skb: socket buffer to add attribute to
966 * @attrtype: attribute type
967 * @addr: IPv4 address
968 */
969static inline int nla_put_in_addr(struct sk_buff *skb, int attrtype,
970 __be32 addr)
971{
972 return nla_put_be32(skb, attrtype, addr);
973}
974
975/**
976 * nla_put_in6_addr - Add an IPv6 address netlink attribute to a socket
977 * buffer
978 * @skb: socket buffer to add attribute to
979 * @attrtype: attribute type
980 * @addr: IPv6 address
981 */
982static inline int nla_put_in6_addr(struct sk_buff *skb, int attrtype,
983 const struct in6_addr *addr)
984{
985 return nla_put(skb, attrtype, sizeof(*addr), addr);
986}
987
988/**
989 * nla_get_u32 - return payload of u32 attribute
990 * @nla: u32 netlink attribute
991 */
992static inline u32 nla_get_u32(const struct nlattr *nla)
993{
994 return *(u32 *) nla_data(nla);
995}
996
997/**
998 * nla_get_be32 - return payload of __be32 attribute
999 * @nla: __be32 netlink attribute
1000 */
1001static inline __be32 nla_get_be32(const struct nlattr *nla)
1002{
1003 return *(__be32 *) nla_data(nla);
1004}
1005
1006/**
1007 * nla_get_le32 - return payload of __le32 attribute
1008 * @nla: __le32 netlink attribute
1009 */
1010static inline __le32 nla_get_le32(const struct nlattr *nla)
1011{
1012 return *(__le32 *) nla_data(nla);
1013}
1014
1015/**
1016 * nla_get_u16 - return payload of u16 attribute
1017 * @nla: u16 netlink attribute
1018 */
1019static inline u16 nla_get_u16(const struct nlattr *nla)
1020{
1021 return *(u16 *) nla_data(nla);
1022}
1023
1024/**
1025 * nla_get_be16 - return payload of __be16 attribute
1026 * @nla: __be16 netlink attribute
1027 */
1028static inline __be16 nla_get_be16(const struct nlattr *nla)
1029{
1030 return *(__be16 *) nla_data(nla);
1031}
1032
1033/**
1034 * nla_get_le16 - return payload of __le16 attribute
1035 * @nla: __le16 netlink attribute
1036 */
1037static inline __le16 nla_get_le16(const struct nlattr *nla)
1038{
1039 return *(__le16 *) nla_data(nla);
1040}
1041
1042/**
1043 * nla_get_u8 - return payload of u8 attribute
1044 * @nla: u8 netlink attribute
1045 */
1046static inline u8 nla_get_u8(const struct nlattr *nla)
1047{
1048 return *(u8 *) nla_data(nla);
1049}
1050
1051/**
1052 * nla_get_u64 - return payload of u64 attribute
1053 * @nla: u64 netlink attribute
1054 */
1055static inline u64 nla_get_u64(const struct nlattr *nla)
1056{
1057 u64 tmp;
1058
1059 nla_memcpy(&tmp, nla, sizeof(tmp));
1060
1061 return tmp;
1062}
1063
1064/**
1065 * nla_get_be64 - return payload of __be64 attribute
1066 * @nla: __be64 netlink attribute
1067 */
1068static inline __be64 nla_get_be64(const struct nlattr *nla)
1069{
1070 __be64 tmp;
1071
1072 nla_memcpy(&tmp, nla, sizeof(tmp));
1073
1074 return tmp;
1075}
1076
1077/**
1078 * nla_get_le64 - return payload of __le64 attribute
1079 * @nla: __le64 netlink attribute
1080 */
1081static inline __le64 nla_get_le64(const struct nlattr *nla)
1082{
1083 return *(__le64 *) nla_data(nla);
1084}
1085
1086/**
1087 * nla_get_s32 - return payload of s32 attribute
1088 * @nla: s32 netlink attribute
1089 */
1090static inline s32 nla_get_s32(const struct nlattr *nla)
1091{
1092 return *(s32 *) nla_data(nla);
1093}
1094
1095/**
1096 * nla_get_s16 - return payload of s16 attribute
1097 * @nla: s16 netlink attribute
1098 */
1099static inline s16 nla_get_s16(const struct nlattr *nla)
1100{
1101 return *(s16 *) nla_data(nla);
1102}
1103
1104/**
1105 * nla_get_s8 - return payload of s8 attribute
1106 * @nla: s8 netlink attribute
1107 */
1108static inline s8 nla_get_s8(const struct nlattr *nla)
1109{
1110 return *(s8 *) nla_data(nla);
1111}
1112
1113/**
1114 * nla_get_s64 - return payload of s64 attribute
1115 * @nla: s64 netlink attribute
1116 */
1117static inline s64 nla_get_s64(const struct nlattr *nla)
1118{
1119 s64 tmp;
1120
1121 nla_memcpy(&tmp, nla, sizeof(tmp));
1122
1123 return tmp;
1124}
1125
1126/**
1127 * nla_get_flag - return payload of flag attribute
1128 * @nla: flag netlink attribute
1129 */
1130static inline int nla_get_flag(const struct nlattr *nla)
1131{
1132 return !!nla;
1133}
1134
1135/**
1136 * nla_get_msecs - return payload of msecs attribute
1137 * @nla: msecs netlink attribute
1138 *
1139 * Returns the number of milliseconds in jiffies.
1140 */
1141static inline unsigned long nla_get_msecs(const struct nlattr *nla)
1142{
1143 u64 msecs = nla_get_u64(nla);
1144
1145 return msecs_to_jiffies((unsigned long) msecs);
1146}
1147
1148/**
1149 * nla_get_in_addr - return payload of IPv4 address attribute
1150 * @nla: IPv4 address netlink attribute
1151 */
1152static inline __be32 nla_get_in_addr(const struct nlattr *nla)
1153{
1154 return *(__be32 *) nla_data(nla);
1155}
1156
1157/**
1158 * nla_get_in6_addr - return payload of IPv6 address attribute
1159 * @nla: IPv6 address netlink attribute
1160 */
1161static inline struct in6_addr nla_get_in6_addr(const struct nlattr *nla)
1162{
1163 struct in6_addr tmp;
1164
1165 nla_memcpy(&tmp, nla, sizeof(tmp));
1166 return tmp;
1167}
1168
1169/**
1170 * nla_nest_start - Start a new level of nested attributes
1171 * @skb: socket buffer to add attributes to
1172 * @attrtype: attribute type of container
1173 *
1174 * Returns the container attribute
1175 */
1176static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
1177{
1178 struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb);
1179
1180 if (nla_put(skb, attrtype, 0, NULL) < 0)
1181 return NULL;
1182
1183 return start;
1184}
1185
1186/**
1187 * nla_nest_end - Finalize nesting of attributes
1188 * @skb: socket buffer the attributes are stored in
1189 * @start: container attribute
1190 *
1191 * Corrects the container attribute header to include the all
1192 * appeneded attributes.
1193 *
1194 * Returns the total data length of the skb.
1195 */
1196static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start)
1197{
1198 start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start;
1199 return skb->len;
1200}
1201
1202/**
1203 * nla_nest_cancel - Cancel nesting of attributes
1204 * @skb: socket buffer the message is stored in
1205 * @start: container attribute
1206 *
1207 * Removes the container attribute and including all nested
1208 * attributes. Returns -EMSGSIZE
1209 */
1210static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start)
1211{
1212 nlmsg_trim(skb, start);
1213}
1214
1215/**
1216 * nla_validate_nested - Validate a stream of nested attributes
1217 * @start: container attribute
1218 * @maxtype: maximum attribute type to be expected
1219 * @policy: validation policy
1220 *
1221 * Validates all attributes in the nested attribute stream against the
1222 * specified policy. Attributes with a type exceeding maxtype will be
1223 * ignored. See documenation of struct nla_policy for more details.
1224 *
1225 * Returns 0 on success or a negative error code.
1226 */
1227static inline int nla_validate_nested(const struct nlattr *start, int maxtype,
1228 const struct nla_policy *policy)
1229{
1230 return nla_validate(nla_data(start), nla_len(start), maxtype, policy);
1231}
1232
1233/**
1234 * nla_for_each_attr - iterate over a stream of attributes
1235 * @pos: loop counter, set to current attribute
1236 * @head: head of attribute stream
1237 * @len: length of attribute stream
1238 * @rem: initialized to len, holds bytes currently remaining in stream
1239 */
1240#define nla_for_each_attr(pos, head, len, rem) \
1241 for (pos = head, rem = len; \
1242 nla_ok(pos, rem); \
1243 pos = nla_next(pos, &(rem)))
1244
1245/**
1246 * nla_for_each_nested - iterate over nested attributes
1247 * @pos: loop counter, set to current attribute
1248 * @nla: attribute containing the nested attributes
1249 * @rem: initialized to len, holds bytes currently remaining in stream
1250 */
1251#define nla_for_each_nested(pos, nla, rem) \
1252 nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)
1253
1254/**
1255 * nla_is_last - Test if attribute is last in stream
1256 * @nla: attribute to test
1257 * @rem: bytes remaining in stream
1258 */
1259static inline bool nla_is_last(const struct nlattr *nla, int rem)
1260{
1261 return nla->nla_len == rem;
1262}
1263
1264#endif