1 #ifndef __NET_NETLINK_H
2 #define __NET_NETLINK_H
4 #include <linux/types.h>
5 #include <linux/netlink.h>
6 #include <linux/jiffies.h>
8 /* ========================================================================
9 * Netlink Messages and Attributes Interface (As Seen On TV)
10 * ------------------------------------------------------------------------
12 * ------------------------------------------------------------------------
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)-----------------------+
24 * <---------------------- nlmsg_len(nlh) --------------------->
25 * <------ hdrlen ------> <- nlmsg_attrlen(nlh, hdrlen) ->
26 * +----------------------+- - -+--------------------------------+
27 * | Family Header | Pad | Attributes |
28 * +----------------------+- - -+--------------------------------+
29 * nlmsg_attrdata(nlh, hdrlen)---^
32 * struct nlmsghdr netlink message header
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() finanlize 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
45 * nlmsg_multicast() multicast message to several groups
46 * nlmsg_unicast() unicast a message to a single socket
47 * nlmsg_notify() send notification message
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
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
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
70 * nlmsg_report() report back to application?
72 * ------------------------------------------------------------------------
73 * Attributes Interface
74 * ------------------------------------------------------------------------
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)-----------------------------'
87 * struct nlattr netlink attribute header
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
95 * Attribute Construction for Basic Types:
96 * nla_put_u8(skb, type, value) add u8 attribute to skb
97 * nla_put_u16(skb, type, value) add u16 attribute to skb
98 * nla_put_u32(skb, type, value) add u32 attribute to skb
99 * nla_put_u64(skb, type, value) add u64 attribute to skb
100 * nla_put_string(skb, type, str) add string attribute to skb
101 * nla_put_flag(skb, type) add flag attribute to skb
102 * nla_put_msecs(skb, type, jiffies) add msecs attribute to skb
104 * Exceptions Based Attribute Construction:
105 * NLA_PUT(skb, type, len, data) add attribute to skb
106 * NLA_PUT_U8(skb, type, value) add u8 attribute to skb
107 * NLA_PUT_U16(skb, type, value) add u16 attribute to skb
108 * NLA_PUT_U32(skb, type, value) add u32 attribute to skb
109 * NLA_PUT_U64(skb, type, value) add u64 attribute to skb
110 * NLA_PUT_STRING(skb, type, str) add string attribute to skb
111 * NLA_PUT_FLAG(skb, type) add flag attribute to skb
112 * NLA_PUT_MSECS(skb, type, jiffies) add msecs attribute to skb
114 * The meaning of these functions is equal to their lower case
115 * variants but they jump to the label nla_put_failure in case
118 * Nested Attributes Construction:
119 * nla_nest_start(skb, type) start a nested attribute
120 * nla_nest_end(skb, nla) finalize a nested attribute
121 * nla_nest_compat_start(skb, type, start a nested compat attribute
123 * nla_nest_compat_end(skb, type) finalize a nested compat attribute
124 * nla_nest_cancel(skb, nla) cancel nested attribute construction
126 * Attribute Length Calculations:
127 * nla_attr_size(payload) length of attribute w/o padding
128 * nla_total_size(payload) length of attribute w/ padding
129 * nla_padlen(payload) length of padding
131 * Attribute Payload Access:
132 * nla_data(nla) head of attribute payload
133 * nla_len(nla) length of attribute payload
135 * Attribute Payload Access for Basic Types:
136 * nla_get_u8(nla) get payload for a u8 attribute
137 * nla_get_u16(nla) get payload for a u16 attribute
138 * nla_get_u32(nla) get payload for a u32 attribute
139 * nla_get_u64(nla) get payload for a u64 attribute
140 * nla_get_flag(nla) return 1 if flag is true
141 * nla_get_msecs(nla) get payload for a msecs attribute
144 * nla_memcpy(dest, nla, count) copy attribute into memory
145 * nla_memcmp(nla, data, size) compare attribute with memory area
146 * nla_strlcpy(dst, nla, size) copy attribute to a sized string
147 * nla_strcmp(nla, str) compare attribute with string
150 * nla_ok(nla, remaining) does nla fit into remaining bytes?
151 * nla_next(nla, remaining) get next netlink attribute
152 * nla_validate() validate a stream of attributes
153 * nla_validate_nested() validate a stream of nested attributes
154 * nla_find() find attribute in stream of attributes
155 * nla_find_nested() find attribute in nested attributes
156 * nla_parse() parse and validate stream of attrs
157 * nla_parse_nested() parse nested attribuets
158 * nla_parse_nested_compat() parse nested compat attributes
159 * nla_for_each_attr() loop over all attributes
160 * nla_for_each_nested() loop over the nested attributes
161 *=========================================================================
165 * Standard attribute types to specify validation policy
183 #define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1)
186 * struct nla_policy - attribute validation policy
187 * @type: Type of attribute or NLA_UNSPEC
188 * @len: Type specific length of payload
190 * Policies are defined as arrays of this struct, the array must be
191 * accessible by attribute type up to the highest identifier to be expected.
193 * Meaning of `len' field:
194 * NLA_STRING Maximum length of string
195 * NLA_NUL_STRING Maximum length of string (excluding NUL)
197 * NLA_BINARY Maximum length of attribute payload
198 * NLA_NESTED_COMPAT Exact length of structure payload
199 * All other Exact length of attribute payload
202 * static struct nla_policy my_policy[ATTR_MAX+1] __read_mostly = {
203 * [ATTR_FOO] = { .type = NLA_U16 },
204 * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ },
205 * [ATTR_BAZ] = { .len = sizeof(struct mystruct) },
214 * struct nl_info - netlink source information
215 * @nlh: Netlink message header of original request
216 * @pid: Netlink PID of requesting application
219 struct nlmsghdr *nlh;
224 extern int netlink_rcv_skb(struct sk_buff *skb,
225 int (*cb)(struct sk_buff *,
227 extern int nlmsg_notify(struct sock *sk, struct sk_buff *skb,
228 u32 pid, unsigned int group, int report,
231 extern int nla_validate(struct nlattr *head, int len, int maxtype,
232 const struct nla_policy *policy);
233 extern int nla_parse(struct nlattr *tb[], int maxtype,
234 struct nlattr *head, int len,
235 const struct nla_policy *policy);
236 extern struct nlattr * nla_find(struct nlattr *head, int len, int attrtype);
237 extern size_t nla_strlcpy(char *dst, const struct nlattr *nla,
239 extern int nla_memcpy(void *dest, struct nlattr *src, int count);
240 extern int nla_memcmp(const struct nlattr *nla, const void *data,
242 extern int nla_strcmp(const struct nlattr *nla, const char *str);
243 extern struct nlattr * __nla_reserve(struct sk_buff *skb, int attrtype,
245 extern void * __nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
246 extern struct nlattr * nla_reserve(struct sk_buff *skb, int attrtype,
248 extern void * nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
249 extern void __nla_put(struct sk_buff *skb, int attrtype,
250 int attrlen, const void *data);
251 extern void __nla_put_nohdr(struct sk_buff *skb, int attrlen,
253 extern int nla_put(struct sk_buff *skb, int attrtype,
254 int attrlen, const void *data);
255 extern int nla_put_nohdr(struct sk_buff *skb, int attrlen,
258 /**************************************************************************
260 **************************************************************************/
263 * nlmsg_msg_size - length of netlink message not including padding
264 * @payload: length of message payload
266 static inline int nlmsg_msg_size(int payload)
268 return NLMSG_HDRLEN + payload;
272 * nlmsg_total_size - length of netlink message including padding
273 * @payload: length of message payload
275 static inline int nlmsg_total_size(int payload)
277 return NLMSG_ALIGN(nlmsg_msg_size(payload));
281 * nlmsg_padlen - length of padding at the message's tail
282 * @payload: length of message payload
284 static inline int nlmsg_padlen(int payload)
286 return nlmsg_total_size(payload) - nlmsg_msg_size(payload);
290 * nlmsg_data - head of message payload
291 * @nlh: netlink messsage header
293 static inline void *nlmsg_data(const struct nlmsghdr *nlh)
295 return (unsigned char *) nlh + NLMSG_HDRLEN;
299 * nlmsg_len - length of message payload
300 * @nlh: netlink message header
302 static inline int nlmsg_len(const struct nlmsghdr *nlh)
304 return nlh->nlmsg_len - NLMSG_HDRLEN;
308 * nlmsg_attrdata - head of attributes data
309 * @nlh: netlink message header
310 * @hdrlen: length of family specific header
312 static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh,
315 unsigned char *data = nlmsg_data(nlh);
316 return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen));
320 * nlmsg_attrlen - length of attributes data
321 * @nlh: netlink message header
322 * @hdrlen: length of family specific header
324 static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen)
326 return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen);
330 * nlmsg_ok - check if the netlink message fits into the remaining bytes
331 * @nlh: netlink message header
332 * @remaining: number of bytes remaining in message stream
334 static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining)
336 return (remaining >= sizeof(struct nlmsghdr) &&
337 nlh->nlmsg_len >= sizeof(struct nlmsghdr) &&
338 nlh->nlmsg_len <= remaining);
342 * nlmsg_next - next netlink message in message stream
343 * @nlh: netlink message header
344 * @remaining: number of bytes remaining in message stream
346 * Returns the next netlink message in the message stream and
347 * decrements remaining by the size of the current message.
349 static inline struct nlmsghdr *nlmsg_next(struct nlmsghdr *nlh, int *remaining)
351 int totlen = NLMSG_ALIGN(nlh->nlmsg_len);
353 *remaining -= totlen;
355 return (struct nlmsghdr *) ((unsigned char *) nlh + totlen);
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
368 static inline int nlmsg_parse(struct nlmsghdr *nlh, int hdrlen,
369 struct nlattr *tb[], int maxtype,
370 const struct nla_policy *policy)
372 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
375 return nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen),
376 nlmsg_attrlen(nlh, hdrlen), policy);
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
385 * Returns the first attribute which matches the specified type.
387 static inline struct nlattr *nlmsg_find_attr(struct nlmsghdr *nlh,
388 int hdrlen, int attrtype)
390 return nla_find(nlmsg_attrdata(nlh, hdrlen),
391 nlmsg_attrlen(nlh, hdrlen), attrtype);
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
401 static inline int nlmsg_validate(struct nlmsghdr *nlh, int hdrlen, int maxtype,
402 const struct nla_policy *policy)
404 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
407 return nla_validate(nlmsg_attrdata(nlh, hdrlen),
408 nlmsg_attrlen(nlh, hdrlen), maxtype, policy);
412 * nlmsg_report - need to report back to application?
413 * @nlh: netlink message header
415 * Returns 1 if a report back to the application is requested.
417 static inline int nlmsg_report(struct nlmsghdr *nlh)
419 return !!(nlh->nlmsg_flags & NLM_F_ECHO);
423 * nlmsg_for_each_attr - iterate over a stream of attributes
424 * @pos: loop counter, set to current attribute
425 * @nlh: netlink message header
426 * @hdrlen: length of familiy specific header
427 * @rem: initialized to len, holds bytes currently remaining in stream
429 #define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \
430 nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \
431 nlmsg_attrlen(nlh, hdrlen), rem)
434 /* FIXME: Enable once all users have been converted */
437 * __nlmsg_put - Add a new netlink message to an skb
438 * @skb: socket buffer to store message in
439 * @pid: netlink process id
440 * @seq: sequence number of message
441 * @type: message type
442 * @payload: length of message payload
443 * @flags: message flags
445 * The caller is responsible to ensure that the skb provides enough
446 * tailroom for both the netlink header and payload.
448 static inline struct nlmsghdr *__nlmsg_put(struct sk_buff *skb, u32 pid,
449 u32 seq, int type, int payload,
452 struct nlmsghdr *nlh;
454 nlh = (struct nlmsghdr *) skb_put(skb, nlmsg_total_size(payload));
455 nlh->nlmsg_type = type;
456 nlh->nlmsg_len = nlmsg_msg_size(payload);
457 nlh->nlmsg_flags = flags;
458 nlh->nlmsg_pid = pid;
459 nlh->nlmsg_seq = seq;
461 memset((unsigned char *) nlmsg_data(nlh) + payload, 0,
462 nlmsg_padlen(payload));
469 * nlmsg_put - Add a new netlink message to an skb
470 * @skb: socket buffer to store message in
471 * @pid: netlink process id
472 * @seq: sequence number of message
473 * @type: message type
474 * @payload: length of message payload
475 * @flags: message flags
477 * Returns NULL if the tailroom of the skb is insufficient to store
478 * the message header and payload.
480 static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
481 int type, int payload, int flags)
483 if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload)))
486 return __nlmsg_put(skb, pid, seq, type, payload, flags);
490 * nlmsg_put_answer - Add a new callback based netlink message to an skb
491 * @skb: socket buffer to store message in
492 * @cb: netlink callback
493 * @type: message type
494 * @payload: length of message payload
495 * @flags: message flags
497 * Returns NULL if the tailroom of the skb is insufficient to store
498 * the message header and payload.
500 static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb,
501 struct netlink_callback *cb,
502 int type, int payload,
505 return nlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
506 type, payload, flags);
510 * nlmsg_new - Allocate a new netlink message
511 * @payload: size of the message payload
512 * @flags: the type of memory to allocate.
514 * Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known
515 * and a good default is needed.
517 static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags)
519 return alloc_skb(nlmsg_total_size(payload), flags);
523 * nlmsg_end - Finalize a netlink message
524 * @skb: socket buffer the message is stored in
525 * @nlh: netlink message header
527 * Corrects the netlink message header to include the appeneded
528 * attributes. Only necessary if attributes have been added to
531 * Returns the total data length of the skb.
533 static inline int nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh)
535 nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh;
541 * nlmsg_get_pos - return current position in netlink message
542 * @skb: socket buffer the message is stored in
544 * Returns a pointer to the current tail of the message.
546 static inline void *nlmsg_get_pos(struct sk_buff *skb)
548 return skb_tail_pointer(skb);
552 * nlmsg_trim - Trim message to a mark
553 * @skb: socket buffer the message is stored in
554 * @mark: mark to trim to
556 * Trims the message to the provided mark. Returns -1.
558 static inline int nlmsg_trim(struct sk_buff *skb, const void *mark)
561 skb_trim(skb, (unsigned char *) mark - skb->data);
567 * nlmsg_cancel - Cancel construction of a netlink message
568 * @skb: socket buffer the message is stored in
569 * @nlh: netlink message header
571 * Removes the complete netlink message including all
572 * attributes from the socket buffer again. Returns -1.
574 static inline int nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh)
576 return nlmsg_trim(skb, nlh);
580 * nlmsg_free - free a netlink message
581 * @skb: socket buffer of netlink message
583 static inline void nlmsg_free(struct sk_buff *skb)
589 * nlmsg_multicast - multicast a netlink message
590 * @sk: netlink socket to spread messages to
591 * @skb: netlink message as socket buffer
592 * @pid: own netlink pid to avoid sending to yourself
593 * @group: multicast group id
594 * @flags: allocation flags
596 static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb,
597 u32 pid, unsigned int group, gfp_t flags)
601 NETLINK_CB(skb).dst_group = group;
603 err = netlink_broadcast(sk, skb, pid, group, flags);
611 * nlmsg_unicast - unicast a netlink message
612 * @sk: netlink socket to spread message to
613 * @skb: netlink message as socket buffer
614 * @pid: netlink pid of the destination socket
616 static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 pid)
620 err = netlink_unicast(sk, skb, pid, MSG_DONTWAIT);
628 * nlmsg_for_each_msg - iterate over a stream of messages
629 * @pos: loop counter, set to current message
630 * @head: head of message stream
631 * @len: length of message stream
632 * @rem: initialized to len, holds bytes currently remaining in stream
634 #define nlmsg_for_each_msg(pos, head, len, rem) \
635 for (pos = head, rem = len; \
636 nlmsg_ok(pos, rem); \
637 pos = nlmsg_next(pos, &(rem)))
639 /**************************************************************************
641 **************************************************************************/
644 * nla_attr_size - length of attribute not including padding
645 * @payload: length of payload
647 static inline int nla_attr_size(int payload)
649 return NLA_HDRLEN + payload;
653 * nla_total_size - total length of attribute including padding
654 * @payload: length of payload
656 static inline int nla_total_size(int payload)
658 return NLA_ALIGN(nla_attr_size(payload));
662 * nla_padlen - length of padding at the tail of attribute
663 * @payload: length of payload
665 static inline int nla_padlen(int payload)
667 return nla_total_size(payload) - nla_attr_size(payload);
671 * nla_type - attribute type
672 * @nla: netlink attribute
674 static inline int nla_type(const struct nlattr *nla)
676 return nla->nla_type & NLA_TYPE_MASK;
680 * nla_data - head of payload
681 * @nla: netlink attribute
683 static inline void *nla_data(const struct nlattr *nla)
685 return (char *) nla + NLA_HDRLEN;
689 * nla_len - length of payload
690 * @nla: netlink attribute
692 static inline int nla_len(const struct nlattr *nla)
694 return nla->nla_len - NLA_HDRLEN;
698 * nla_ok - check if the netlink attribute fits into the remaining bytes
699 * @nla: netlink attribute
700 * @remaining: number of bytes remaining in attribute stream
702 static inline int nla_ok(const struct nlattr *nla, int remaining)
704 return remaining >= sizeof(*nla) &&
705 nla->nla_len >= sizeof(*nla) &&
706 nla->nla_len <= remaining;
710 * nla_next - next netlink attribute in attribute stream
711 * @nla: netlink attribute
712 * @remaining: number of bytes remaining in attribute stream
714 * Returns the next netlink attribute in the attribute stream and
715 * decrements remaining by the size of the current attribute.
717 static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining)
719 int totlen = NLA_ALIGN(nla->nla_len);
721 *remaining -= totlen;
722 return (struct nlattr *) ((char *) nla + totlen);
726 * nla_find_nested - find attribute in a set of nested attributes
727 * @nla: attribute containing the nested attributes
728 * @attrtype: type of attribute to look for
730 * Returns the first attribute which matches the specified type.
732 static inline struct nlattr *nla_find_nested(struct nlattr *nla, int attrtype)
734 return nla_find(nla_data(nla), nla_len(nla), attrtype);
738 * nla_parse_nested - parse nested attributes
739 * @tb: destination array with maxtype+1 elements
740 * @maxtype: maximum attribute type to be expected
741 * @nla: attribute containing the nested attributes
742 * @policy: validation policy
746 static inline int nla_parse_nested(struct nlattr *tb[], int maxtype,
748 const struct nla_policy *policy)
750 return nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy);
754 * nla_parse_nested_compat - parse nested compat attributes
755 * @tb: destination array with maxtype+1 elements
756 * @maxtype: maximum attribute type to be expected
757 * @nla: attribute containing the nested attributes
758 * @data: pointer to point to contained structure
759 * @len: length of contained structure
760 * @policy: validation policy
762 * Parse a nested compat attribute. The compat attribute contains a structure
763 * and optionally a set of nested attributes. On success the data pointer
764 * points to the nested data and tb contains the parsed attributes
767 static inline int __nla_parse_nested_compat(struct nlattr *tb[], int maxtype,
769 const struct nla_policy *policy,
772 if (nla_len(nla) < len)
774 if (nla_len(nla) >= NLA_ALIGN(len) + sizeof(struct nlattr))
775 return nla_parse_nested(tb, maxtype,
776 nla_data(nla) + NLA_ALIGN(len),
778 memset(tb, 0, sizeof(struct nlattr *) * (maxtype + 1));
782 #define nla_parse_nested_compat(tb, maxtype, nla, policy, data, len) \
783 ({ data = nla_len(nla) >= len ? nla_data(nla) : NULL; \
784 __nla_parse_nested_compat(tb, maxtype, nla, policy, len); })
786 * nla_put_u8 - Add a u8 netlink attribute to a socket buffer
787 * @skb: socket buffer to add attribute to
788 * @attrtype: attribute type
789 * @value: numeric value
791 static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value)
793 return nla_put(skb, attrtype, sizeof(u8), &value);
797 * nla_put_u16 - Add a u16 netlink attribute to a socket buffer
798 * @skb: socket buffer to add attribute to
799 * @attrtype: attribute type
800 * @value: numeric value
802 static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value)
804 return nla_put(skb, attrtype, sizeof(u16), &value);
808 * nla_put_u32 - Add a u32 netlink attribute to a socket buffer
809 * @skb: socket buffer to add attribute to
810 * @attrtype: attribute type
811 * @value: numeric value
813 static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value)
815 return nla_put(skb, attrtype, sizeof(u32), &value);
819 * nla_put_64 - Add a u64 netlink attribute to a socket buffer
820 * @skb: socket buffer to add attribute to
821 * @attrtype: attribute type
822 * @value: numeric value
824 static inline int nla_put_u64(struct sk_buff *skb, int attrtype, u64 value)
826 return nla_put(skb, attrtype, sizeof(u64), &value);
830 * nla_put_string - Add a string netlink attribute to a socket buffer
831 * @skb: socket buffer to add attribute to
832 * @attrtype: attribute type
833 * @str: NUL terminated string
835 static inline int nla_put_string(struct sk_buff *skb, int attrtype,
838 return nla_put(skb, attrtype, strlen(str) + 1, str);
842 * nla_put_flag - Add a flag netlink attribute to a socket buffer
843 * @skb: socket buffer to add attribute to
844 * @attrtype: attribute type
846 static inline int nla_put_flag(struct sk_buff *skb, int attrtype)
848 return nla_put(skb, attrtype, 0, NULL);
852 * nla_put_msecs - Add a msecs netlink attribute to a socket buffer
853 * @skb: socket buffer to add attribute to
854 * @attrtype: attribute type
855 * @jiffies: number of msecs in jiffies
857 static inline int nla_put_msecs(struct sk_buff *skb, int attrtype,
858 unsigned long jiffies)
860 u64 tmp = jiffies_to_msecs(jiffies);
861 return nla_put(skb, attrtype, sizeof(u64), &tmp);
864 #define NLA_PUT(skb, attrtype, attrlen, data) \
866 if (unlikely(nla_put(skb, attrtype, attrlen, data) < 0)) \
867 goto nla_put_failure; \
870 #define NLA_PUT_TYPE(skb, type, attrtype, value) \
872 type __tmp = value; \
873 NLA_PUT(skb, attrtype, sizeof(type), &__tmp); \
876 #define NLA_PUT_U8(skb, attrtype, value) \
877 NLA_PUT_TYPE(skb, u8, attrtype, value)
879 #define NLA_PUT_U16(skb, attrtype, value) \
880 NLA_PUT_TYPE(skb, u16, attrtype, value)
882 #define NLA_PUT_LE16(skb, attrtype, value) \
883 NLA_PUT_TYPE(skb, __le16, attrtype, value)
885 #define NLA_PUT_BE16(skb, attrtype, value) \
886 NLA_PUT_TYPE(skb, __be16, attrtype, value)
888 #define NLA_PUT_U32(skb, attrtype, value) \
889 NLA_PUT_TYPE(skb, u32, attrtype, value)
891 #define NLA_PUT_BE32(skb, attrtype, value) \
892 NLA_PUT_TYPE(skb, __be32, attrtype, value)
894 #define NLA_PUT_U64(skb, attrtype, value) \
895 NLA_PUT_TYPE(skb, u64, attrtype, value)
897 #define NLA_PUT_STRING(skb, attrtype, value) \
898 NLA_PUT(skb, attrtype, strlen(value) + 1, value)
900 #define NLA_PUT_FLAG(skb, attrtype) \
901 NLA_PUT(skb, attrtype, 0, NULL)
903 #define NLA_PUT_MSECS(skb, attrtype, jiffies) \
904 NLA_PUT_U64(skb, attrtype, jiffies_to_msecs(jiffies))
907 * nla_get_u32 - return payload of u32 attribute
908 * @nla: u32 netlink attribute
910 static inline u32 nla_get_u32(struct nlattr *nla)
912 return *(u32 *) nla_data(nla);
916 * nla_get_be32 - return payload of __be32 attribute
917 * @nla: __be32 netlink attribute
919 static inline __be32 nla_get_be32(struct nlattr *nla)
921 return *(__be32 *) nla_data(nla);
925 * nla_get_u16 - return payload of u16 attribute
926 * @nla: u16 netlink attribute
928 static inline u16 nla_get_u16(struct nlattr *nla)
930 return *(u16 *) nla_data(nla);
934 * nla_get_be16 - return payload of __be16 attribute
935 * @nla: __be16 netlink attribute
937 static inline __be16 nla_get_be16(struct nlattr *nla)
939 return *(__be16 *) nla_data(nla);
943 * nla_get_le16 - return payload of __le16 attribute
944 * @nla: __le16 netlink attribute
946 static inline __le16 nla_get_le16(struct nlattr *nla)
948 return *(__le16 *) nla_data(nla);
952 * nla_get_u8 - return payload of u8 attribute
953 * @nla: u8 netlink attribute
955 static inline u8 nla_get_u8(struct nlattr *nla)
957 return *(u8 *) nla_data(nla);
961 * nla_get_u64 - return payload of u64 attribute
962 * @nla: u64 netlink attribute
964 static inline u64 nla_get_u64(struct nlattr *nla)
968 nla_memcpy(&tmp, nla, sizeof(tmp));
974 * nla_get_flag - return payload of flag attribute
975 * @nla: flag netlink attribute
977 static inline int nla_get_flag(struct nlattr *nla)
983 * nla_get_msecs - return payload of msecs attribute
984 * @nla: msecs netlink attribute
986 * Returns the number of milliseconds in jiffies.
988 static inline unsigned long nla_get_msecs(struct nlattr *nla)
990 u64 msecs = nla_get_u64(nla);
992 return msecs_to_jiffies((unsigned long) msecs);
996 * nla_nest_start - Start a new level of nested attributes
997 * @skb: socket buffer to add attributes to
998 * @attrtype: attribute type of container
1000 * Returns the container attribute
1002 static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
1004 struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb);
1006 if (nla_put(skb, attrtype, 0, NULL) < 0)
1013 * nla_nest_end - Finalize nesting of attributes
1014 * @skb: socket buffer the attributes are stored in
1015 * @start: container attribute
1017 * Corrects the container attribute header to include the all
1018 * appeneded attributes.
1020 * Returns the total data length of the skb.
1022 static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start)
1024 start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start;
1029 * nla_nest_compat_start - Start a new level of nested compat attributes
1030 * @skb: socket buffer to add attributes to
1031 * @attrtype: attribute type of container
1032 * @attrlen: length of structure
1033 * @data: pointer to structure
1035 * Start a nested compat attribute that contains both a structure and
1036 * a set of nested attributes.
1038 * Returns the container attribute
1040 static inline struct nlattr *nla_nest_compat_start(struct sk_buff *skb,
1041 int attrtype, int attrlen,
1044 struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb);
1046 if (nla_put(skb, attrtype, attrlen, data) < 0)
1048 if (nla_nest_start(skb, attrtype) == NULL) {
1049 nlmsg_trim(skb, start);
1056 * nla_nest_compat_end - Finalize nesting of compat attributes
1057 * @skb: socket buffer the attributes are stored in
1058 * @start: container attribute
1060 * Corrects the container attribute header to include the all
1061 * appeneded attributes.
1063 * Returns the total data length of the skb.
1065 static inline int nla_nest_compat_end(struct sk_buff *skb, struct nlattr *start)
1067 struct nlattr *nest = (void *)start + NLMSG_ALIGN(start->nla_len);
1069 start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start;
1070 return nla_nest_end(skb, nest);
1074 * nla_nest_cancel - Cancel nesting of attributes
1075 * @skb: socket buffer the message is stored in
1076 * @start: container attribute
1078 * Removes the container attribute and including all nested
1079 * attributes. Returns -1.
1081 static inline int nla_nest_cancel(struct sk_buff *skb, struct nlattr *start)
1083 return nlmsg_trim(skb, start);
1087 * nla_validate_nested - Validate a stream of nested attributes
1088 * @start: container attribute
1089 * @maxtype: maximum attribute type to be expected
1090 * @policy: validation policy
1092 * Validates all attributes in the nested attribute stream against the
1093 * specified policy. Attributes with a type exceeding maxtype will be
1094 * ignored. See documenation of struct nla_policy for more details.
1096 * Returns 0 on success or a negative error code.
1098 static inline int nla_validate_nested(struct nlattr *start, int maxtype,
1099 const struct nla_policy *policy)
1101 return nla_validate(nla_data(start), nla_len(start), maxtype, policy);
1105 * nla_for_each_attr - iterate over a stream of attributes
1106 * @pos: loop counter, set to current attribute
1107 * @head: head of attribute stream
1108 * @len: length of attribute stream
1109 * @rem: initialized to len, holds bytes currently remaining in stream
1111 #define nla_for_each_attr(pos, head, len, rem) \
1112 for (pos = head, rem = len; \
1114 pos = nla_next(pos, &(rem)))
1117 * nla_for_each_nested - iterate over nested attributes
1118 * @pos: loop counter, set to current attribute
1119 * @nla: attribute containing the nested attributes
1120 * @rem: initialized to len, holds bytes currently remaining in stream
1122 #define nla_for_each_nested(pos, nla, rem) \
1123 nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)