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Thomas Grafbfa83a92005-11-10 02:25:51 +01001#ifndef __NET_NETLINK_H
2#define __NET_NETLINK_H
3
4#include <linux/types.h>
5#include <linux/netlink.h>
Al Virod7fe0f22006-12-03 23:15:30 -05006#include <linux/jiffies.h>
Jiri Benc930345e2015-03-29 16:59:25 +02007#include <linux/in6.h>
Thomas Grafbfa83a92005-11-10 02:25:51 +01008
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()
Justin P. Mattock1dc8d8c2010-06-21 13:45:42 -070039 * nlmsg_end() finalize netlink message
Thomas Graffe4944e2006-08-04 23:03:05 -070040 * nlmsg_get_pos() return current position in message
41 * nlmsg_trim() trim part of message
Thomas Grafbfa83a92005-11-10 02:25:51 +010042 * 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
Thomas Grafd387f6a2006-08-15 00:31:06 -070048 * nlmsg_notify() send notification message
Thomas Grafbfa83a92005-11-10 02:25:51 +010049 *
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 *
Thomas Graf97676b62006-08-15 00:31:41 -070070 * Misc:
71 * nlmsg_report() report back to application?
72 *
Thomas Grafbfa83a92005-11-10 02:25:51 +010073 * ------------------------------------------------------------------------
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:
Pierre Ynardd1ec3b72007-10-10 21:09:48 -070088 * struct nlattr netlink attribute header
Thomas Grafbfa83a92005-11-10 02:25:51 +010089 *
90 * Attribute Construction:
Thomas Graffe4944e2006-08-04 23:03:05 -070091 * nla_reserve(skb, type, len) reserve room for an attribute
92 * nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr
Thomas Grafbfa83a92005-11-10 02:25:51 +010093 * nla_put(skb, type, len, data) add attribute to skb
Thomas Graffe4944e2006-08-04 23:03:05 -070094 * nla_put_nohdr(skb, len, data) add attribute w/o hdr
Patrick McHardy01480e12008-01-22 22:10:59 -080095 * nla_append(skb, len, data) append data to skb
Thomas Grafbfa83a92005-11-10 02:25:51 +010096 *
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
Nicolas Dichtel50225242016-05-13 15:25:40 +0200101 * nla_put_u64_64bits(skb, type,
102 * value, padattr) add u64 attribute to skb
Jiri Pirko4778e0b2012-07-27 06:28:52 +0000103 * nla_put_s8(skb, type, value) add s8 attribute to skb
104 * nla_put_s16(skb, type, value) add s16 attribute to skb
105 * nla_put_s32(skb, type, value) add s32 attribute to skb
Nicolas Dichtel756a2f52016-04-22 17:31:20 +0200106 * nla_put_s64(skb, type, value,
107 * padattr) add s64 attribute to skb
Thomas Grafbfa83a92005-11-10 02:25:51 +0100108 * nla_put_string(skb, type, str) add string attribute to skb
109 * nla_put_flag(skb, type) add flag attribute to skb
Nicolas Dichtel2175d872016-04-22 17:31:21 +0200110 * nla_put_msecs(skb, type, jiffies,
111 * padattr) add msecs attribute to skb
Jiri Benc930345e2015-03-29 16:59:25 +0200112 * nla_put_in_addr(skb, type, addr) add IPv4 address attribute to skb
113 * nla_put_in6_addr(skb, type, addr) add IPv6 address attribute to skb
Thomas Grafbfa83a92005-11-10 02:25:51 +0100114 *
Thomas Grafbfa83a92005-11-10 02:25:51 +0100115 * Nested Attributes Construction:
116 * nla_nest_start(skb, type) start a nested attribute
117 * nla_nest_end(skb, nla) finalize a nested attribute
118 * nla_nest_cancel(skb, nla) cancel nested attribute construction
119 *
120 * Attribute Length Calculations:
121 * nla_attr_size(payload) length of attribute w/o padding
122 * nla_total_size(payload) length of attribute w/ padding
123 * nla_padlen(payload) length of padding
124 *
125 * Attribute Payload Access:
126 * nla_data(nla) head of attribute payload
127 * nla_len(nla) length of attribute payload
128 *
129 * Attribute Payload Access for Basic Types:
130 * nla_get_u8(nla) get payload for a u8 attribute
131 * nla_get_u16(nla) get payload for a u16 attribute
132 * nla_get_u32(nla) get payload for a u32 attribute
133 * nla_get_u64(nla) get payload for a u64 attribute
Jiri Pirko4778e0b2012-07-27 06:28:52 +0000134 * nla_get_s8(nla) get payload for a s8 attribute
135 * nla_get_s16(nla) get payload for a s16 attribute
136 * nla_get_s32(nla) get payload for a s32 attribute
137 * nla_get_s64(nla) get payload for a s64 attribute
Thomas Grafbfa83a92005-11-10 02:25:51 +0100138 * nla_get_flag(nla) return 1 if flag is true
139 * nla_get_msecs(nla) get payload for a msecs attribute
140 *
141 * Attribute Misc:
142 * nla_memcpy(dest, nla, count) copy attribute into memory
143 * nla_memcmp(nla, data, size) compare attribute with memory area
144 * nla_strlcpy(dst, nla, size) copy attribute to a sized string
145 * nla_strcmp(nla, str) compare attribute with string
146 *
147 * Attribute Parsing:
148 * nla_ok(nla, remaining) does nla fit into remaining bytes?
149 * nla_next(nla, remaining) get next netlink attribute
150 * nla_validate() validate a stream of attributes
Paul Moore4fe5d5c2006-09-25 15:54:03 -0700151 * nla_validate_nested() validate a stream of nested attributes
Thomas Grafbfa83a92005-11-10 02:25:51 +0100152 * nla_find() find attribute in stream of attributes
Thomas Graffe4944e2006-08-04 23:03:05 -0700153 * nla_find_nested() find attribute in nested attributes
Thomas Grafbfa83a92005-11-10 02:25:51 +0100154 * nla_parse() parse and validate stream of attrs
155 * nla_parse_nested() parse nested attribuets
156 * nla_for_each_attr() loop over all attributes
Paul Moore22acb192006-09-25 15:53:37 -0700157 * nla_for_each_nested() loop over the nested attributes
Thomas Grafbfa83a92005-11-10 02:25:51 +0100158 *=========================================================================
159 */
160
161 /**
162 * Standard attribute types to specify validation policy
163 */
164enum {
165 NLA_UNSPEC,
166 NLA_U8,
167 NLA_U16,
168 NLA_U32,
169 NLA_U64,
170 NLA_STRING,
171 NLA_FLAG,
172 NLA_MSECS,
173 NLA_NESTED,
Patrick McHardy1092cb22007-06-25 13:49:35 -0700174 NLA_NESTED_COMPAT,
Thomas Grafa5531a52006-08-26 20:11:47 -0700175 NLA_NUL_STRING,
Johannes Bergd30045a2007-03-23 11:37:48 -0700176 NLA_BINARY,
Jiri Pirko4778e0b2012-07-27 06:28:52 +0000177 NLA_S8,
178 NLA_S16,
179 NLA_S32,
180 NLA_S64,
Thomas Grafbfa83a92005-11-10 02:25:51 +0100181 __NLA_TYPE_MAX,
182};
183
184#define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1)
185
186/**
187 * struct nla_policy - attribute validation policy
188 * @type: Type of attribute or NLA_UNSPEC
Thomas Grafa5531a52006-08-26 20:11:47 -0700189 * @len: Type specific length of payload
Thomas Grafbfa83a92005-11-10 02:25:51 +0100190 *
191 * Policies are defined as arrays of this struct, the array must be
192 * accessible by attribute type up to the highest identifier to be expected.
193 *
Thomas Grafa5531a52006-08-26 20:11:47 -0700194 * Meaning of `len' field:
195 * NLA_STRING Maximum length of string
196 * NLA_NUL_STRING Maximum length of string (excluding NUL)
197 * NLA_FLAG Unused
Johannes Bergd30045a2007-03-23 11:37:48 -0700198 * NLA_BINARY Maximum length of attribute payload
Johannes Berg4b6cc722011-11-03 00:10:05 +0000199 * NLA_NESTED Don't use `len' field -- length verification is
200 * done by checking len of nested header (or empty)
201 * NLA_NESTED_COMPAT Minimum length of structure payload
202 * NLA_U8, NLA_U16,
203 * NLA_U32, NLA_U64,
Jiri Pirko4778e0b2012-07-27 06:28:52 +0000204 * NLA_S8, NLA_S16,
205 * NLA_S32, NLA_S64,
Johannes Berg4b6cc722011-11-03 00:10:05 +0000206 * NLA_MSECS Leaving the length field zero will verify the
207 * given type fits, using it verifies minimum length
208 * just like "All other"
209 * All other Minimum length of attribute payload
Thomas Grafa5531a52006-08-26 20:11:47 -0700210 *
Thomas Grafbfa83a92005-11-10 02:25:51 +0100211 * Example:
Alexey Dobriyanb54452b2010-02-18 08:14:31 +0000212 * static const struct nla_policy my_policy[ATTR_MAX+1] = {
Thomas Grafbfa83a92005-11-10 02:25:51 +0100213 * [ATTR_FOO] = { .type = NLA_U16 },
Johannes Bergd30045a2007-03-23 11:37:48 -0700214 * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ },
Thomas Grafa5531a52006-08-26 20:11:47 -0700215 * [ATTR_BAZ] = { .len = sizeof(struct mystruct) },
Thomas Grafbfa83a92005-11-10 02:25:51 +0100216 * };
217 */
218struct nla_policy {
219 u16 type;
Thomas Grafa5531a52006-08-26 20:11:47 -0700220 u16 len;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100221};
222
Thomas Graf4e902c52006-08-17 18:14:52 -0700223/**
224 * struct nl_info - netlink source information
225 * @nlh: Netlink message header of original request
Eric W. Biederman15e47302012-09-07 20:12:54 +0000226 * @portid: Netlink PORTID of requesting application
Thomas Graf4e902c52006-08-17 18:14:52 -0700227 */
228struct nl_info {
229 struct nlmsghdr *nlh;
Denis V. Lunev4d1169c2008-01-10 03:26:13 -0800230 struct net *nl_net;
Eric W. Biederman15e47302012-09-07 20:12:54 +0000231 u32 portid;
Thomas Graf4e902c52006-08-17 18:14:52 -0700232};
233
Joe Perches4f690532013-09-21 10:22:50 -0700234int netlink_rcv_skb(struct sk_buff *skb,
235 int (*cb)(struct sk_buff *, struct nlmsghdr *));
236int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid,
237 unsigned int group, int report, gfp_t flags);
Thomas Graf82ace472005-11-10 02:25:53 +0100238
Joe Perches4f690532013-09-21 10:22:50 -0700239int nla_validate(const struct nlattr *head, int len, int maxtype,
240 const struct nla_policy *policy);
241int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
242 int len, const struct nla_policy *policy);
243int nla_policy_len(const struct nla_policy *, int);
244struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype);
245size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize);
246int nla_memcpy(void *dest, const struct nlattr *src, int count);
247int nla_memcmp(const struct nlattr *nla, const void *data, size_t size);
248int nla_strcmp(const struct nlattr *nla, const char *str);
249struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen);
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200250struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype,
251 int attrlen, int padattr);
Joe Perches4f690532013-09-21 10:22:50 -0700252void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
253struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen);
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200254struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype,
255 int attrlen, int padattr);
Joe Perches4f690532013-09-21 10:22:50 -0700256void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
257void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
258 const void *data);
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200259void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
260 const void *data, int padattr);
Joe Perches4f690532013-09-21 10:22:50 -0700261void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data);
262int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data);
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +0200263int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
264 const void *data, int padattr);
Joe Perches4f690532013-09-21 10:22:50 -0700265int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data);
266int nla_append(struct sk_buff *skb, int attrlen, const void *data);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100267
268/**************************************************************************
269 * Netlink Messages
270 **************************************************************************/
271
272/**
273 * nlmsg_msg_size - length of netlink message not including padding
274 * @payload: length of message payload
275 */
276static inline int nlmsg_msg_size(int payload)
277{
278 return NLMSG_HDRLEN + payload;
279}
280
281/**
282 * nlmsg_total_size - length of netlink message including padding
283 * @payload: length of message payload
284 */
285static inline int nlmsg_total_size(int payload)
286{
287 return NLMSG_ALIGN(nlmsg_msg_size(payload));
288}
289
290/**
291 * nlmsg_padlen - length of padding at the message's tail
292 * @payload: length of message payload
293 */
294static inline int nlmsg_padlen(int payload)
295{
296 return nlmsg_total_size(payload) - nlmsg_msg_size(payload);
297}
298
299/**
300 * nlmsg_data - head of message payload
Justin P. Mattock70f23fd2011-05-10 10:16:21 +0200301 * @nlh: netlink message header
Thomas Grafbfa83a92005-11-10 02:25:51 +0100302 */
303static inline void *nlmsg_data(const struct nlmsghdr *nlh)
304{
305 return (unsigned char *) nlh + NLMSG_HDRLEN;
306}
307
308/**
309 * nlmsg_len - length of message payload
310 * @nlh: netlink message header
311 */
312static inline int nlmsg_len(const struct nlmsghdr *nlh)
313{
314 return nlh->nlmsg_len - NLMSG_HDRLEN;
315}
316
317/**
318 * nlmsg_attrdata - head of attributes data
319 * @nlh: netlink message header
320 * @hdrlen: length of family specific header
321 */
322static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh,
323 int hdrlen)
324{
325 unsigned char *data = nlmsg_data(nlh);
326 return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen));
327}
328
329/**
330 * nlmsg_attrlen - length of attributes data
331 * @nlh: netlink message header
332 * @hdrlen: length of family specific header
333 */
334static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen)
335{
336 return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen);
337}
338
339/**
340 * nlmsg_ok - check if the netlink message fits into the remaining bytes
341 * @nlh: netlink message header
342 * @remaining: number of bytes remaining in message stream
343 */
344static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining)
345{
Vegard Nossum619e8032008-12-25 17:21:17 -0800346 return (remaining >= (int) sizeof(struct nlmsghdr) &&
Thomas Grafbfa83a92005-11-10 02:25:51 +0100347 nlh->nlmsg_len >= sizeof(struct nlmsghdr) &&
348 nlh->nlmsg_len <= remaining);
349}
350
351/**
352 * nlmsg_next - next netlink message in message stream
353 * @nlh: netlink message header
354 * @remaining: number of bytes remaining in message stream
355 *
356 * Returns the next netlink message in the message stream and
357 * decrements remaining by the size of the current message.
358 */
Jan Engelhardt36546542010-11-16 09:52:32 -0800359static inline struct nlmsghdr *
360nlmsg_next(const struct nlmsghdr *nlh, int *remaining)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100361{
362 int totlen = NLMSG_ALIGN(nlh->nlmsg_len);
363
364 *remaining -= totlen;
365
366 return (struct nlmsghdr *) ((unsigned char *) nlh + totlen);
367}
368
369/**
370 * nlmsg_parse - parse attributes of a netlink message
371 * @nlh: netlink message header
372 * @hdrlen: length of family specific header
373 * @tb: destination array with maxtype+1 elements
374 * @maxtype: maximum attribute type to be expected
375 * @policy: validation policy
376 *
377 * See nla_parse()
378 */
Patrick McHardy3a6c2b42009-08-25 16:07:40 +0200379static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen,
Thomas Grafbfa83a92005-11-10 02:25:51 +0100380 struct nlattr *tb[], int maxtype,
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700381 const struct nla_policy *policy)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100382{
383 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
384 return -EINVAL;
385
386 return nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen),
387 nlmsg_attrlen(nlh, hdrlen), policy);
388}
389
390/**
391 * nlmsg_find_attr - find a specific attribute in a netlink message
392 * @nlh: netlink message header
393 * @hdrlen: length of familiy specific header
394 * @attrtype: type of attribute to look for
395 *
396 * Returns the first attribute which matches the specified type.
397 */
Nelson Elhage6b8c92b2010-11-03 16:35:40 +0000398static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh,
Thomas Grafbfa83a92005-11-10 02:25:51 +0100399 int hdrlen, int attrtype)
400{
401 return nla_find(nlmsg_attrdata(nlh, hdrlen),
402 nlmsg_attrlen(nlh, hdrlen), attrtype);
403}
404
405/**
406 * nlmsg_validate - validate a netlink message including attributes
407 * @nlh: netlinket message header
408 * @hdrlen: length of familiy specific header
409 * @maxtype: maximum attribute type to be expected
410 * @policy: validation policy
411 */
Jan Engelhardt36546542010-11-16 09:52:32 -0800412static inline int nlmsg_validate(const struct nlmsghdr *nlh,
413 int hdrlen, int maxtype,
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700414 const struct nla_policy *policy)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100415{
416 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
417 return -EINVAL;
418
419 return nla_validate(nlmsg_attrdata(nlh, hdrlen),
420 nlmsg_attrlen(nlh, hdrlen), maxtype, policy);
421}
422
423/**
Thomas Graf97676b62006-08-15 00:31:41 -0700424 * nlmsg_report - need to report back to application?
425 * @nlh: netlink message header
426 *
427 * Returns 1 if a report back to the application is requested.
428 */
Patrick McHardy3a6c2b42009-08-25 16:07:40 +0200429static inline int nlmsg_report(const struct nlmsghdr *nlh)
Thomas Graf97676b62006-08-15 00:31:41 -0700430{
431 return !!(nlh->nlmsg_flags & NLM_F_ECHO);
432}
433
434/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100435 * nlmsg_for_each_attr - iterate over a stream of attributes
436 * @pos: loop counter, set to current attribute
437 * @nlh: netlink message header
438 * @hdrlen: length of familiy specific header
439 * @rem: initialized to len, holds bytes currently remaining in stream
440 */
441#define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \
442 nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \
443 nlmsg_attrlen(nlh, hdrlen), rem)
444
Thomas Grafbfa83a92005-11-10 02:25:51 +0100445/**
446 * nlmsg_put - Add a new netlink message to an skb
447 * @skb: socket buffer to store message in
Nicolas Dichtel2c6ba4b2014-10-16 15:47:51 +0200448 * @portid: netlink PORTID of requesting application
Thomas Grafbfa83a92005-11-10 02:25:51 +0100449 * @seq: sequence number of message
450 * @type: message type
451 * @payload: length of message payload
452 * @flags: message flags
453 *
454 * Returns NULL if the tailroom of the skb is insufficient to store
455 * the message header and payload.
456 */
Eric W. Biederman15e47302012-09-07 20:12:54 +0000457static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
Thomas Grafbfa83a92005-11-10 02:25:51 +0100458 int type, int payload, int flags)
459{
460 if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload)))
461 return NULL;
462
Eric W. Biederman15e47302012-09-07 20:12:54 +0000463 return __nlmsg_put(skb, portid, seq, type, payload, flags);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100464}
465
466/**
467 * nlmsg_put_answer - Add a new callback based netlink message to an skb
468 * @skb: socket buffer to store message in
469 * @cb: netlink callback
470 * @type: message type
471 * @payload: length of message payload
472 * @flags: message flags
473 *
474 * Returns NULL if the tailroom of the skb is insufficient to store
475 * the message header and payload.
476 */
477static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb,
478 struct netlink_callback *cb,
479 int type, int payload,
480 int flags)
481{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000482 return nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
Thomas Grafbfa83a92005-11-10 02:25:51 +0100483 type, payload, flags);
484}
485
486/**
487 * nlmsg_new - Allocate a new netlink message
Thomas Graf339bf982006-11-10 14:10:15 -0800488 * @payload: size of the message payload
Thomas Graffe4944e2006-08-04 23:03:05 -0700489 * @flags: the type of memory to allocate.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100490 *
Thomas Graf339bf982006-11-10 14:10:15 -0800491 * Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known
492 * and a good default is needed.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100493 */
Thomas Graf339bf982006-11-10 14:10:15 -0800494static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100495{
Thomas Graf339bf982006-11-10 14:10:15 -0800496 return alloc_skb(nlmsg_total_size(payload), flags);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100497}
498
499/**
500 * nlmsg_end - Finalize a netlink message
501 * @skb: socket buffer the message is stored in
502 * @nlh: netlink message header
503 *
504 * Corrects the netlink message header to include the appeneded
505 * attributes. Only necessary if attributes have been added to
506 * the message.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100507 */
Johannes Berg053c0952015-01-16 22:09:00 +0100508static inline void nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100509{
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700510 nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh;
Thomas Grafbfa83a92005-11-10 02:25:51 +0100511}
512
513/**
Thomas Graffe4944e2006-08-04 23:03:05 -0700514 * nlmsg_get_pos - return current position in netlink message
515 * @skb: socket buffer the message is stored in
516 *
517 * Returns a pointer to the current tail of the message.
518 */
519static inline void *nlmsg_get_pos(struct sk_buff *skb)
520{
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700521 return skb_tail_pointer(skb);
Thomas Graffe4944e2006-08-04 23:03:05 -0700522}
523
524/**
525 * nlmsg_trim - Trim message to a mark
526 * @skb: socket buffer the message is stored in
527 * @mark: mark to trim to
528 *
Thomas Grafbc3ed282008-06-03 16:36:54 -0700529 * Trims the message to the provided mark.
Thomas Graffe4944e2006-08-04 23:03:05 -0700530 */
Thomas Grafbc3ed282008-06-03 16:36:54 -0700531static inline void nlmsg_trim(struct sk_buff *skb, const void *mark)
Thomas Graffe4944e2006-08-04 23:03:05 -0700532{
Thomas Graf149118d2015-01-06 01:04:21 +0100533 if (mark) {
534 WARN_ON((unsigned char *) mark < skb->data);
Thomas Graffe4944e2006-08-04 23:03:05 -0700535 skb_trim(skb, (unsigned char *) mark - skb->data);
Thomas Graf149118d2015-01-06 01:04:21 +0100536 }
Thomas Graffe4944e2006-08-04 23:03:05 -0700537}
538
539/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100540 * nlmsg_cancel - Cancel construction of a netlink message
541 * @skb: socket buffer the message is stored in
542 * @nlh: netlink message header
543 *
544 * Removes the complete netlink message including all
Thomas Grafbc3ed282008-06-03 16:36:54 -0700545 * attributes from the socket buffer again.
Thomas Grafbfa83a92005-11-10 02:25:51 +0100546 */
Thomas Grafbc3ed282008-06-03 16:36:54 -0700547static inline void nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100548{
Thomas Grafbc3ed282008-06-03 16:36:54 -0700549 nlmsg_trim(skb, nlh);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100550}
551
552/**
553 * nlmsg_free - free a netlink message
554 * @skb: socket buffer of netlink message
555 */
556static inline void nlmsg_free(struct sk_buff *skb)
557{
558 kfree_skb(skb);
559}
560
561/**
562 * nlmsg_multicast - multicast a netlink message
563 * @sk: netlink socket to spread messages to
564 * @skb: netlink message as socket buffer
Eric W. Biederman15e47302012-09-07 20:12:54 +0000565 * @portid: own netlink portid to avoid sending to yourself
Thomas Grafbfa83a92005-11-10 02:25:51 +0100566 * @group: multicast group id
Thomas Grafd387f6a2006-08-15 00:31:06 -0700567 * @flags: allocation flags
Thomas Grafbfa83a92005-11-10 02:25:51 +0100568 */
569static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb,
Eric W. Biederman15e47302012-09-07 20:12:54 +0000570 u32 portid, unsigned int group, gfp_t flags)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100571{
572 int err;
573
574 NETLINK_CB(skb).dst_group = group;
575
Eric W. Biederman15e47302012-09-07 20:12:54 +0000576 err = netlink_broadcast(sk, skb, portid, group, flags);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100577 if (err > 0)
578 err = 0;
579
580 return err;
581}
582
583/**
584 * nlmsg_unicast - unicast a netlink message
585 * @sk: netlink socket to spread message to
586 * @skb: netlink message as socket buffer
Eric W. Biederman15e47302012-09-07 20:12:54 +0000587 * @portid: netlink portid of the destination socket
Thomas Grafbfa83a92005-11-10 02:25:51 +0100588 */
Eric W. Biederman15e47302012-09-07 20:12:54 +0000589static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 portid)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100590{
591 int err;
592
Eric W. Biederman15e47302012-09-07 20:12:54 +0000593 err = netlink_unicast(sk, skb, portid, MSG_DONTWAIT);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100594 if (err > 0)
595 err = 0;
596
597 return err;
598}
599
600/**
601 * nlmsg_for_each_msg - iterate over a stream of messages
602 * @pos: loop counter, set to current message
603 * @head: head of message stream
604 * @len: length of message stream
605 * @rem: initialized to len, holds bytes currently remaining in stream
606 */
607#define nlmsg_for_each_msg(pos, head, len, rem) \
608 for (pos = head, rem = len; \
609 nlmsg_ok(pos, rem); \
610 pos = nlmsg_next(pos, &(rem)))
611
Johannes Berg670dc282011-06-20 13:40:46 +0200612/**
613 * nl_dump_check_consistent - check if sequence is consistent and advertise if not
614 * @cb: netlink callback structure that stores the sequence number
615 * @nlh: netlink message header to write the flag to
616 *
617 * This function checks if the sequence (generation) number changed during dump
618 * and if it did, advertises it in the netlink message header.
619 *
620 * The correct way to use it is to set cb->seq to the generation counter when
621 * all locks for dumping have been acquired, and then call this function for
622 * each message that is generated.
623 *
624 * Note that due to initialisation concerns, 0 is an invalid sequence number
625 * and must not be used by code that uses this functionality.
626 */
627static inline void
628nl_dump_check_consistent(struct netlink_callback *cb,
629 struct nlmsghdr *nlh)
630{
631 if (cb->prev_seq && cb->seq != cb->prev_seq)
632 nlh->nlmsg_flags |= NLM_F_DUMP_INTR;
633 cb->prev_seq = cb->seq;
634}
635
Thomas Grafbfa83a92005-11-10 02:25:51 +0100636/**************************************************************************
637 * Netlink Attributes
638 **************************************************************************/
639
640/**
641 * nla_attr_size - length of attribute not including padding
642 * @payload: length of payload
643 */
644static inline int nla_attr_size(int payload)
645{
646 return NLA_HDRLEN + payload;
647}
648
649/**
650 * nla_total_size - total length of attribute including padding
651 * @payload: length of payload
652 */
653static inline int nla_total_size(int payload)
654{
655 return NLA_ALIGN(nla_attr_size(payload));
656}
657
658/**
659 * nla_padlen - length of padding at the tail of attribute
660 * @payload: length of payload
661 */
662static inline int nla_padlen(int payload)
663{
664 return nla_total_size(payload) - nla_attr_size(payload);
665}
666
667/**
Thomas Graf8f4c1f92007-09-12 14:44:36 +0200668 * nla_type - attribute type
669 * @nla: netlink attribute
670 */
671static inline int nla_type(const struct nlattr *nla)
672{
673 return nla->nla_type & NLA_TYPE_MASK;
674}
675
676/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100677 * nla_data - head of payload
678 * @nla: netlink attribute
679 */
680static inline void *nla_data(const struct nlattr *nla)
681{
682 return (char *) nla + NLA_HDRLEN;
683}
684
685/**
686 * nla_len - length of payload
687 * @nla: netlink attribute
688 */
689static inline int nla_len(const struct nlattr *nla)
690{
691 return nla->nla_len - NLA_HDRLEN;
692}
693
694/**
695 * nla_ok - check if the netlink attribute fits into the remaining bytes
696 * @nla: netlink attribute
697 * @remaining: number of bytes remaining in attribute stream
698 */
699static inline int nla_ok(const struct nlattr *nla, int remaining)
700{
Vegard Nossum1045b032008-09-11 19:05:29 -0700701 return remaining >= (int) sizeof(*nla) &&
Thomas Grafbfa83a92005-11-10 02:25:51 +0100702 nla->nla_len >= sizeof(*nla) &&
703 nla->nla_len <= remaining;
704}
705
706/**
Pierre Ynardd1ec3b72007-10-10 21:09:48 -0700707 * nla_next - next netlink attribute in attribute stream
Thomas Grafbfa83a92005-11-10 02:25:51 +0100708 * @nla: netlink attribute
709 * @remaining: number of bytes remaining in attribute stream
710 *
711 * Returns the next netlink attribute in the attribute stream and
712 * decrements remaining by the size of the current attribute.
713 */
714static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining)
715{
716 int totlen = NLA_ALIGN(nla->nla_len);
717
718 *remaining -= totlen;
719 return (struct nlattr *) ((char *) nla + totlen);
720}
721
722/**
Thomas Graffe4944e2006-08-04 23:03:05 -0700723 * nla_find_nested - find attribute in a set of nested attributes
724 * @nla: attribute containing the nested attributes
725 * @attrtype: type of attribute to look for
726 *
727 * Returns the first attribute which matches the specified type.
728 */
Jan Engelhardt36546542010-11-16 09:52:32 -0800729static inline struct nlattr *
730nla_find_nested(const struct nlattr *nla, int attrtype)
Thomas Graffe4944e2006-08-04 23:03:05 -0700731{
732 return nla_find(nla_data(nla), nla_len(nla), attrtype);
733}
734
735/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100736 * nla_parse_nested - parse nested attributes
737 * @tb: destination array with maxtype+1 elements
738 * @maxtype: maximum attribute type to be expected
739 * @nla: attribute containing the nested attributes
740 * @policy: validation policy
741 *
742 * See nla_parse()
743 */
744static inline int nla_parse_nested(struct nlattr *tb[], int maxtype,
Patrick McHardyb057efd2008-10-28 11:59:11 -0700745 const struct nlattr *nla,
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700746 const struct nla_policy *policy)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100747{
748 return nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy);
749}
Patrick McHardy1092cb22007-06-25 13:49:35 -0700750
751/**
Pierre Ynardd1ec3b72007-10-10 21:09:48 -0700752 * nla_put_u8 - Add a u8 netlink attribute to a socket buffer
Thomas Grafbfa83a92005-11-10 02:25:51 +0100753 * @skb: socket buffer to add attribute to
754 * @attrtype: attribute type
755 * @value: numeric value
756 */
757static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value)
758{
759 return nla_put(skb, attrtype, sizeof(u8), &value);
760}
761
762/**
763 * nla_put_u16 - Add a u16 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_u16(struct sk_buff *skb, int attrtype, u16 value)
769{
770 return nla_put(skb, attrtype, sizeof(u16), &value);
771}
772
773/**
David S. Miller569a8fc2012-03-29 23:18:53 -0400774 * nla_put_be16 - Add a __be16 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_be16(struct sk_buff *skb, int attrtype, __be16 value)
780{
781 return nla_put(skb, attrtype, sizeof(__be16), &value);
782}
783
784/**
David S. Miller6c1dd3b2012-04-01 19:11:31 -0400785 * nla_put_net16 - Add 16-bit network byte order 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_net16(struct sk_buff *skb, int attrtype, __be16 value)
791{
792 return nla_put_be16(skb, attrtype | NLA_F_NET_BYTEORDER, value);
793}
794
795/**
David S. Miller24c410d2012-04-01 20:14:27 -0400796 * nla_put_le16 - Add a __le16 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_le16(struct sk_buff *skb, int attrtype, __le16 value)
802{
803 return nla_put(skb, attrtype, sizeof(__le16), &value);
804}
805
806/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100807 * nla_put_u32 - Add a u32 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_u32(struct sk_buff *skb, int attrtype, u32 value)
813{
814 return nla_put(skb, attrtype, sizeof(u32), &value);
815}
816
817/**
David S. Miller569a8fc2012-03-29 23:18:53 -0400818 * nla_put_be32 - Add a __be32 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_be32(struct sk_buff *skb, int attrtype, __be32 value)
824{
825 return nla_put(skb, attrtype, sizeof(__be32), &value);
826}
827
828/**
David S. Miller6c1dd3b2012-04-01 19:11:31 -0400829 * nla_put_net32 - Add 32-bit network byte order 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_net32(struct sk_buff *skb, int attrtype, __be32 value)
835{
836 return nla_put_be32(skb, attrtype | NLA_F_NET_BYTEORDER, value);
837}
838
839/**
David S. Miller24c410d2012-04-01 20:14:27 -0400840 * nla_put_le32 - Add a __le32 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_le32(struct sk_buff *skb, int attrtype, __le32 value)
846{
847 return nla_put(skb, attrtype, sizeof(__le32), &value);
848}
849
850/**
Nicolas Dichtel73520782016-04-22 17:31:22 +0200851 * nla_put_u64_64bit - Add a u64 netlink attribute to a skb and align it
852 * @skb: socket buffer to add attribute to
853 * @attrtype: attribute type
854 * @value: numeric value
855 * @padattr: attribute type for the padding
856 */
857static inline int nla_put_u64_64bit(struct sk_buff *skb, int attrtype,
858 u64 value, int padattr)
859{
860 return nla_put_64bit(skb, attrtype, sizeof(u64), &value, padattr);
861}
862
863/**
Nicolas Dichtelb46f6de2016-04-22 17:31:18 +0200864 * nla_put_be64 - Add a __be64 netlink attribute to a socket buffer and align it
David S. Miller569a8fc2012-03-29 23:18:53 -0400865 * @skb: socket buffer to add attribute to
866 * @attrtype: attribute type
867 * @value: numeric value
Nicolas Dichtelb46f6de2016-04-22 17:31:18 +0200868 * @padattr: attribute type for the padding
David S. Miller569a8fc2012-03-29 23:18:53 -0400869 */
Nicolas Dichtelb46f6de2016-04-22 17:31:18 +0200870static inline int nla_put_be64(struct sk_buff *skb, int attrtype, __be64 value,
871 int padattr)
872{
873 return nla_put_64bit(skb, attrtype, sizeof(__be64), &value, padattr);
874}
875
David S. Miller569a8fc2012-03-29 23:18:53 -0400876/**
Nicolas Dichtele9bbe892016-04-22 17:31:19 +0200877 * nla_put_net64 - Add 64-bit network byte order nlattr to a skb and align it
David S. Miller6c1dd3b2012-04-01 19:11:31 -0400878 * @skb: socket buffer to add attribute to
879 * @attrtype: attribute type
880 * @value: numeric value
Nicolas Dichtele9bbe892016-04-22 17:31:19 +0200881 * @padattr: attribute type for the padding
David S. Miller6c1dd3b2012-04-01 19:11:31 -0400882 */
Nicolas Dichtele9bbe892016-04-22 17:31:19 +0200883static inline int nla_put_net64(struct sk_buff *skb, int attrtype, __be64 value,
884 int padattr)
David S. Miller6c1dd3b2012-04-01 19:11:31 -0400885{
Nicolas Dichtele9bbe892016-04-22 17:31:19 +0200886 return nla_put_be64(skb, attrtype | NLA_F_NET_BYTEORDER, value,
887 padattr);
David S. Miller6c1dd3b2012-04-01 19:11:31 -0400888}
889
890/**
Nicolas Dichtele74791222016-04-22 17:31:17 +0200891 * nla_put_le64 - Add a __le64 netlink attribute to a socket buffer and align it
David S. Miller24c410d2012-04-01 20:14:27 -0400892 * @skb: socket buffer to add attribute to
893 * @attrtype: attribute type
894 * @value: numeric value
Nicolas Dichtele74791222016-04-22 17:31:17 +0200895 * @padattr: attribute type for the padding
David S. Miller24c410d2012-04-01 20:14:27 -0400896 */
Nicolas Dichtele74791222016-04-22 17:31:17 +0200897static inline int nla_put_le64(struct sk_buff *skb, int attrtype, __le64 value,
898 int padattr)
David S. Miller24c410d2012-04-01 20:14:27 -0400899{
Nicolas Dichtele74791222016-04-22 17:31:17 +0200900 return nla_put_64bit(skb, attrtype, sizeof(__le64), &value, padattr);
David S. Miller24c410d2012-04-01 20:14:27 -0400901}
902
903/**
Jiri Pirko4778e0b2012-07-27 06:28:52 +0000904 * nla_put_s8 - Add a s8 netlink attribute to a socket buffer
905 * @skb: socket buffer to add attribute to
906 * @attrtype: attribute type
907 * @value: numeric value
908 */
909static inline int nla_put_s8(struct sk_buff *skb, int attrtype, s8 value)
910{
911 return nla_put(skb, attrtype, sizeof(s8), &value);
912}
913
914/**
915 * nla_put_s16 - Add a s16 netlink attribute to a socket buffer
916 * @skb: socket buffer to add attribute to
917 * @attrtype: attribute type
918 * @value: numeric value
919 */
920static inline int nla_put_s16(struct sk_buff *skb, int attrtype, s16 value)
921{
922 return nla_put(skb, attrtype, sizeof(s16), &value);
923}
924
925/**
926 * nla_put_s32 - Add a s32 netlink attribute to a socket buffer
927 * @skb: socket buffer to add attribute to
928 * @attrtype: attribute type
929 * @value: numeric value
930 */
931static inline int nla_put_s32(struct sk_buff *skb, int attrtype, s32 value)
932{
933 return nla_put(skb, attrtype, sizeof(s32), &value);
934}
935
936/**
Nicolas Dichtel756a2f52016-04-22 17:31:20 +0200937 * nla_put_s64 - Add a s64 netlink attribute to a socket buffer and align it
Jiri Pirko4778e0b2012-07-27 06:28:52 +0000938 * @skb: socket buffer to add attribute to
939 * @attrtype: attribute type
940 * @value: numeric value
Nicolas Dichtel756a2f52016-04-22 17:31:20 +0200941 * @padattr: attribute type for the padding
Jiri Pirko4778e0b2012-07-27 06:28:52 +0000942 */
Nicolas Dichtel756a2f52016-04-22 17:31:20 +0200943static inline int nla_put_s64(struct sk_buff *skb, int attrtype, s64 value,
944 int padattr)
Jiri Pirko4778e0b2012-07-27 06:28:52 +0000945{
Nicolas Dichtel756a2f52016-04-22 17:31:20 +0200946 return nla_put_64bit(skb, attrtype, sizeof(s64), &value, padattr);
Jiri Pirko4778e0b2012-07-27 06:28:52 +0000947}
948
949/**
Thomas Grafbfa83a92005-11-10 02:25:51 +0100950 * nla_put_string - Add a string netlink attribute to a socket buffer
951 * @skb: socket buffer to add attribute to
952 * @attrtype: attribute type
953 * @str: NUL terminated string
954 */
955static inline int nla_put_string(struct sk_buff *skb, int attrtype,
956 const char *str)
957{
958 return nla_put(skb, attrtype, strlen(str) + 1, str);
959}
960
961/**
962 * nla_put_flag - Add a flag netlink attribute to a socket buffer
963 * @skb: socket buffer to add attribute to
964 * @attrtype: attribute type
965 */
966static inline int nla_put_flag(struct sk_buff *skb, int attrtype)
967{
968 return nla_put(skb, attrtype, 0, NULL);
969}
970
971/**
Nicolas Dichtel2175d872016-04-22 17:31:21 +0200972 * nla_put_msecs - Add a msecs netlink attribute to a skb and align it
Thomas Grafbfa83a92005-11-10 02:25:51 +0100973 * @skb: socket buffer to add attribute to
974 * @attrtype: attribute type
Mark Rustadd87de1f2014-07-25 02:18:17 -0700975 * @njiffies: number of jiffies to convert to msecs
Nicolas Dichtel2175d872016-04-22 17:31:21 +0200976 * @padattr: attribute type for the padding
Thomas Grafbfa83a92005-11-10 02:25:51 +0100977 */
978static inline int nla_put_msecs(struct sk_buff *skb, int attrtype,
Nicolas Dichtel2175d872016-04-22 17:31:21 +0200979 unsigned long njiffies, int padattr)
Thomas Grafbfa83a92005-11-10 02:25:51 +0100980{
Mark Rustadd87de1f2014-07-25 02:18:17 -0700981 u64 tmp = jiffies_to_msecs(njiffies);
Nicolas Dichtel2175d872016-04-22 17:31:21 +0200982
983 return nla_put_64bit(skb, attrtype, sizeof(u64), &tmp, padattr);
Thomas Grafbfa83a92005-11-10 02:25:51 +0100984}
985
Thomas Grafbfa83a92005-11-10 02:25:51 +0100986/**
Jiri Benc930345e2015-03-29 16:59:25 +0200987 * nla_put_in_addr - Add an IPv4 address netlink attribute to a socket
988 * buffer
989 * @skb: socket buffer to add attribute to
990 * @attrtype: attribute type
991 * @addr: IPv4 address
992 */
993static inline int nla_put_in_addr(struct sk_buff *skb, int attrtype,
994 __be32 addr)
995{
996 return nla_put_be32(skb, attrtype, addr);
997}
998
999/**
1000 * nla_put_in6_addr - Add an IPv6 address netlink attribute to a socket
1001 * buffer
1002 * @skb: socket buffer to add attribute to
1003 * @attrtype: attribute type
1004 * @addr: IPv6 address
1005 */
1006static inline int nla_put_in6_addr(struct sk_buff *skb, int attrtype,
1007 const struct in6_addr *addr)
1008{
1009 return nla_put(skb, attrtype, sizeof(*addr), addr);
1010}
1011
1012/**
Thomas Grafbfa83a92005-11-10 02:25:51 +01001013 * nla_get_u32 - return payload of u32 attribute
1014 * @nla: u32 netlink attribute
1015 */
Patrick McHardyb057efd2008-10-28 11:59:11 -07001016static inline u32 nla_get_u32(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +01001017{
1018 return *(u32 *) nla_data(nla);
1019}
1020
1021/**
Al Viro00012e52006-09-26 22:14:41 -07001022 * nla_get_be32 - return payload of __be32 attribute
1023 * @nla: __be32 netlink attribute
1024 */
Patrick McHardyb057efd2008-10-28 11:59:11 -07001025static inline __be32 nla_get_be32(const struct nlattr *nla)
Al Viro00012e52006-09-26 22:14:41 -07001026{
1027 return *(__be32 *) nla_data(nla);
1028}
1029
1030/**
Alexander Aringc648a012015-09-28 09:00:23 +02001031 * nla_get_le32 - return payload of __le32 attribute
1032 * @nla: __le32 netlink attribute
1033 */
1034static inline __le32 nla_get_le32(const struct nlattr *nla)
1035{
1036 return *(__le32 *) nla_data(nla);
1037}
1038
1039/**
Thomas Grafbfa83a92005-11-10 02:25:51 +01001040 * nla_get_u16 - return payload of u16 attribute
1041 * @nla: u16 netlink attribute
1042 */
Patrick McHardyb057efd2008-10-28 11:59:11 -07001043static inline u16 nla_get_u16(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +01001044{
1045 return *(u16 *) nla_data(nla);
1046}
1047
1048/**
Patrick McHardy838965b2007-12-17 22:29:26 -08001049 * nla_get_be16 - return payload of __be16 attribute
1050 * @nla: __be16 netlink attribute
1051 */
Patrick McHardyb057efd2008-10-28 11:59:11 -07001052static inline __be16 nla_get_be16(const struct nlattr *nla)
Patrick McHardy838965b2007-12-17 22:29:26 -08001053{
1054 return *(__be16 *) nla_data(nla);
1055}
1056
1057/**
Thomas Graf4a89c252006-11-24 17:14:51 -08001058 * nla_get_le16 - return payload of __le16 attribute
1059 * @nla: __le16 netlink attribute
1060 */
Patrick McHardyb057efd2008-10-28 11:59:11 -07001061static inline __le16 nla_get_le16(const struct nlattr *nla)
Thomas Graf4a89c252006-11-24 17:14:51 -08001062{
1063 return *(__le16 *) nla_data(nla);
1064}
1065
1066/**
Thomas Grafbfa83a92005-11-10 02:25:51 +01001067 * nla_get_u8 - return payload of u8 attribute
1068 * @nla: u8 netlink attribute
1069 */
Patrick McHardyb057efd2008-10-28 11:59:11 -07001070static inline u8 nla_get_u8(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +01001071{
1072 return *(u8 *) nla_data(nla);
1073}
1074
1075/**
1076 * nla_get_u64 - return payload of u64 attribute
1077 * @nla: u64 netlink attribute
1078 */
Patrick McHardyb057efd2008-10-28 11:59:11 -07001079static inline u64 nla_get_u64(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +01001080{
1081 u64 tmp;
1082
1083 nla_memcpy(&tmp, nla, sizeof(tmp));
1084
1085 return tmp;
1086}
1087
1088/**
Pablo Neira Ayusoa17c8592009-05-27 17:50:35 +02001089 * nla_get_be64 - return payload of __be64 attribute
1090 * @nla: __be64 netlink attribute
1091 */
1092static inline __be64 nla_get_be64(const struct nlattr *nla)
1093{
Pablo Neira Ayusof5d410f2010-03-16 13:30:44 +00001094 __be64 tmp;
1095
1096 nla_memcpy(&tmp, nla, sizeof(tmp));
1097
1098 return tmp;
Pablo Neira Ayusoa17c8592009-05-27 17:50:35 +02001099}
1100
1101/**
Alexander Aringc648a012015-09-28 09:00:23 +02001102 * nla_get_le64 - return payload of __le64 attribute
1103 * @nla: __le64 netlink attribute
1104 */
1105static inline __le64 nla_get_le64(const struct nlattr *nla)
1106{
1107 return *(__le64 *) nla_data(nla);
1108}
1109
1110/**
Jiri Pirko4778e0b2012-07-27 06:28:52 +00001111 * nla_get_s32 - return payload of s32 attribute
1112 * @nla: s32 netlink attribute
1113 */
1114static inline s32 nla_get_s32(const struct nlattr *nla)
1115{
1116 return *(s32 *) nla_data(nla);
1117}
1118
1119/**
1120 * nla_get_s16 - return payload of s16 attribute
1121 * @nla: s16 netlink attribute
1122 */
1123static inline s16 nla_get_s16(const struct nlattr *nla)
1124{
1125 return *(s16 *) nla_data(nla);
1126}
1127
1128/**
1129 * nla_get_s8 - return payload of s8 attribute
1130 * @nla: s8 netlink attribute
1131 */
1132static inline s8 nla_get_s8(const struct nlattr *nla)
1133{
1134 return *(s8 *) nla_data(nla);
1135}
1136
1137/**
1138 * nla_get_s64 - return payload of s64 attribute
1139 * @nla: s64 netlink attribute
1140 */
1141static inline s64 nla_get_s64(const struct nlattr *nla)
1142{
1143 s64 tmp;
1144
1145 nla_memcpy(&tmp, nla, sizeof(tmp));
1146
1147 return tmp;
1148}
1149
1150/**
Thomas Grafbfa83a92005-11-10 02:25:51 +01001151 * nla_get_flag - return payload of flag attribute
1152 * @nla: flag netlink attribute
1153 */
Patrick McHardyb057efd2008-10-28 11:59:11 -07001154static inline int nla_get_flag(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +01001155{
1156 return !!nla;
1157}
1158
1159/**
1160 * nla_get_msecs - return payload of msecs attribute
1161 * @nla: msecs netlink attribute
1162 *
1163 * Returns the number of milliseconds in jiffies.
1164 */
Patrick McHardyb057efd2008-10-28 11:59:11 -07001165static inline unsigned long nla_get_msecs(const struct nlattr *nla)
Thomas Grafbfa83a92005-11-10 02:25:51 +01001166{
1167 u64 msecs = nla_get_u64(nla);
1168
1169 return msecs_to_jiffies((unsigned long) msecs);
1170}
1171
1172/**
Jiri Benc67b61f62015-03-29 16:59:26 +02001173 * nla_get_in_addr - return payload of IPv4 address attribute
1174 * @nla: IPv4 address netlink attribute
1175 */
1176static inline __be32 nla_get_in_addr(const struct nlattr *nla)
1177{
1178 return *(__be32 *) nla_data(nla);
1179}
1180
1181/**
1182 * nla_get_in6_addr - return payload of IPv6 address attribute
1183 * @nla: IPv6 address netlink attribute
1184 */
1185static inline struct in6_addr nla_get_in6_addr(const struct nlattr *nla)
1186{
1187 struct in6_addr tmp;
1188
1189 nla_memcpy(&tmp, nla, sizeof(tmp));
1190 return tmp;
1191}
1192
1193/**
Thomas Grafbfa83a92005-11-10 02:25:51 +01001194 * nla_nest_start - Start a new level of nested attributes
1195 * @skb: socket buffer to add attributes to
1196 * @attrtype: attribute type of container
1197 *
1198 * Returns the container attribute
1199 */
1200static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
1201{
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07001202 struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb);
Thomas Grafbfa83a92005-11-10 02:25:51 +01001203
1204 if (nla_put(skb, attrtype, 0, NULL) < 0)
1205 return NULL;
1206
1207 return start;
1208}
1209
1210/**
1211 * nla_nest_end - Finalize nesting of attributes
Pierre Ynardd1ec3b72007-10-10 21:09:48 -07001212 * @skb: socket buffer the attributes are stored in
Thomas Grafbfa83a92005-11-10 02:25:51 +01001213 * @start: container attribute
1214 *
1215 * Corrects the container attribute header to include the all
1216 * appeneded attributes.
1217 *
1218 * Returns the total data length of the skb.
1219 */
1220static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start)
1221{
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07001222 start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start;
Thomas Grafbfa83a92005-11-10 02:25:51 +01001223 return skb->len;
1224}
1225
1226/**
1227 * nla_nest_cancel - Cancel nesting of attributes
1228 * @skb: socket buffer the message is stored in
1229 * @start: container attribute
1230 *
1231 * Removes the container attribute and including all nested
Thomas Grafbc3ed282008-06-03 16:36:54 -07001232 * attributes. Returns -EMSGSIZE
Thomas Grafbfa83a92005-11-10 02:25:51 +01001233 */
Thomas Grafbc3ed282008-06-03 16:36:54 -07001234static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start)
Thomas Grafbfa83a92005-11-10 02:25:51 +01001235{
Thomas Grafbc3ed282008-06-03 16:36:54 -07001236 nlmsg_trim(skb, start);
Thomas Grafbfa83a92005-11-10 02:25:51 +01001237}
1238
1239/**
Paul Moore4fe5d5c2006-09-25 15:54:03 -07001240 * nla_validate_nested - Validate a stream of nested attributes
1241 * @start: container attribute
1242 * @maxtype: maximum attribute type to be expected
1243 * @policy: validation policy
1244 *
1245 * Validates all attributes in the nested attribute stream against the
1246 * specified policy. Attributes with a type exceeding maxtype will be
1247 * ignored. See documenation of struct nla_policy for more details.
1248 *
1249 * Returns 0 on success or a negative error code.
1250 */
Jan Engelhardt36546542010-11-16 09:52:32 -08001251static inline int nla_validate_nested(const struct nlattr *start, int maxtype,
Patrick McHardyef7c79e2007-06-05 12:38:30 -07001252 const struct nla_policy *policy)
Paul Moore4fe5d5c2006-09-25 15:54:03 -07001253{
1254 return nla_validate(nla_data(start), nla_len(start), maxtype, policy);
1255}
1256
1257/**
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +02001258 * nla_need_padding_for_64bit - test 64-bit alignment of the next attribute
1259 * @skb: socket buffer the message is stored in
1260 *
1261 * Return true if padding is needed to align the next attribute (nla_data()) to
1262 * a 64-bit aligned area.
1263 */
1264static inline bool nla_need_padding_for_64bit(struct sk_buff *skb)
1265{
1266#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1267 /* The nlattr header is 4 bytes in size, that's why we test
1268 * if the skb->data _is_ aligned. A NOP attribute, plus
1269 * nlattr header for next attribute, will make nla_data()
1270 * 8-byte aligned.
1271 */
1272 if (IS_ALIGNED((unsigned long)skb_tail_pointer(skb), 8))
1273 return true;
1274#endif
1275 return false;
1276}
1277
1278/**
David S. Miller35c58452016-04-19 19:49:29 -04001279 * nla_align_64bit - 64-bit align the nla_data() of next attribute
1280 * @skb: socket buffer the message is stored in
1281 * @padattr: attribute type for the padding
1282 *
1283 * Conditionally emit a padding netlink attribute in order to make
1284 * the next attribute we emit have a 64-bit aligned nla_data() area.
1285 * This will only be done in architectures which do not have
Eric Dumazetcca1d812016-04-20 07:31:31 -07001286 * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS defined.
David S. Miller35c58452016-04-19 19:49:29 -04001287 *
1288 * Returns zero on success or a negative error code.
1289 */
1290static inline int nla_align_64bit(struct sk_buff *skb, int padattr)
1291{
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +02001292 if (nla_need_padding_for_64bit(skb) &&
Eric Dumazetcca1d812016-04-20 07:31:31 -07001293 !nla_reserve(skb, padattr, 0))
1294 return -EMSGSIZE;
Nicolas Dichtel089bf1a2016-04-21 18:58:24 +02001295
David S. Miller35c58452016-04-19 19:49:29 -04001296 return 0;
1297}
1298
1299/**
1300 * nla_total_size_64bit - total length of attribute including padding
1301 * @payload: length of payload
1302 */
1303static inline int nla_total_size_64bit(int payload)
1304{
1305 return NLA_ALIGN(nla_attr_size(payload))
Eric Dumazetcca1d812016-04-20 07:31:31 -07001306#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
David S. Miller35c58452016-04-19 19:49:29 -04001307 + NLA_ALIGN(nla_attr_size(0))
1308#endif
1309 ;
1310}
1311
1312/**
Thomas Grafbfa83a92005-11-10 02:25:51 +01001313 * nla_for_each_attr - iterate over a stream of attributes
1314 * @pos: loop counter, set to current attribute
1315 * @head: head of attribute stream
1316 * @len: length of attribute stream
1317 * @rem: initialized to len, holds bytes currently remaining in stream
1318 */
1319#define nla_for_each_attr(pos, head, len, rem) \
1320 for (pos = head, rem = len; \
1321 nla_ok(pos, rem); \
1322 pos = nla_next(pos, &(rem)))
1323
Thomas Graffe4944e2006-08-04 23:03:05 -07001324/**
1325 * nla_for_each_nested - iterate over nested attributes
1326 * @pos: loop counter, set to current attribute
1327 * @nla: attribute containing the nested attributes
1328 * @rem: initialized to len, holds bytes currently remaining in stream
1329 */
1330#define nla_for_each_nested(pos, nla, rem) \
1331 nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)
1332
Simon Horman941d8eb2014-10-27 16:12:16 +09001333/**
1334 * nla_is_last - Test if attribute is last in stream
1335 * @nla: attribute to test
1336 * @rem: bytes remaining in stream
1337 */
1338static inline bool nla_is_last(const struct nlattr *nla, int rem)
1339{
1340 return nla->nla_len == rem;
1341}
1342
Thomas Grafbfa83a92005-11-10 02:25:51 +01001343#endif