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-rw-r--r--net/Kconfig1
-rw-r--r--net/netlink/Makefile2
-rw-r--r--net/netlink/attr.c473
3 files changed, 2 insertions, 474 deletions
diff --git a/net/Kconfig b/net/Kconfig
index cdb8fdef6c4a..eab40a481356 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -4,6 +4,7 @@
4 4
5menuconfig NET 5menuconfig NET
6 bool "Networking support" 6 bool "Networking support"
7 select NLATTR
7 ---help--- 8 ---help---
8 Unless you really know what you are doing, you should say Y here. 9 Unless you really know what you are doing, you should say Y here.
9 The reason is that some programs need kernel networking support even 10 The reason is that some programs need kernel networking support even
diff --git a/net/netlink/Makefile b/net/netlink/Makefile
index e3589c2de49e..bdd6ddf4e95b 100644
--- a/net/netlink/Makefile
+++ b/net/netlink/Makefile
@@ -2,4 +2,4 @@
2# Makefile for the netlink driver. 2# Makefile for the netlink driver.
3# 3#
4 4
5obj-y := af_netlink.o attr.o genetlink.o 5obj-y := af_netlink.o genetlink.o
diff --git a/net/netlink/attr.c b/net/netlink/attr.c
deleted file mode 100644
index 56c3ce7fe29a..000000000000
--- a/net/netlink/attr.c
+++ /dev/null
@@ -1,473 +0,0 @@
1/*
2 * NETLINK Netlink attributes
3 *
4 * Authors: Thomas Graf <tgraf@suug.ch>
5 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
6 */
7
8#include <linux/module.h>
9#include <linux/kernel.h>
10#include <linux/errno.h>
11#include <linux/jiffies.h>
12#include <linux/netdevice.h>
13#include <linux/skbuff.h>
14#include <linux/string.h>
15#include <linux/types.h>
16#include <net/netlink.h>
17
18static u16 nla_attr_minlen[NLA_TYPE_MAX+1] __read_mostly = {
19 [NLA_U8] = sizeof(u8),
20 [NLA_U16] = sizeof(u16),
21 [NLA_U32] = sizeof(u32),
22 [NLA_U64] = sizeof(u64),
23 [NLA_NESTED] = NLA_HDRLEN,
24};
25
26static int validate_nla(struct nlattr *nla, int maxtype,
27 const struct nla_policy *policy)
28{
29 const struct nla_policy *pt;
30 int minlen = 0, attrlen = nla_len(nla), type = nla_type(nla);
31
32 if (type <= 0 || type > maxtype)
33 return 0;
34
35 pt = &policy[type];
36
37 BUG_ON(pt->type > NLA_TYPE_MAX);
38
39 switch (pt->type) {
40 case NLA_FLAG:
41 if (attrlen > 0)
42 return -ERANGE;
43 break;
44
45 case NLA_NUL_STRING:
46 if (pt->len)
47 minlen = min_t(int, attrlen, pt->len + 1);
48 else
49 minlen = attrlen;
50
51 if (!minlen || memchr(nla_data(nla), '\0', minlen) == NULL)
52 return -EINVAL;
53 /* fall through */
54
55 case NLA_STRING:
56 if (attrlen < 1)
57 return -ERANGE;
58
59 if (pt->len) {
60 char *buf = nla_data(nla);
61
62 if (buf[attrlen - 1] == '\0')
63 attrlen--;
64
65 if (attrlen > pt->len)
66 return -ERANGE;
67 }
68 break;
69
70 case NLA_BINARY:
71 if (pt->len && attrlen > pt->len)
72 return -ERANGE;
73 break;
74
75 case NLA_NESTED_COMPAT:
76 if (attrlen < pt->len)
77 return -ERANGE;
78 if (attrlen < NLA_ALIGN(pt->len))
79 break;
80 if (attrlen < NLA_ALIGN(pt->len) + NLA_HDRLEN)
81 return -ERANGE;
82 nla = nla_data(nla) + NLA_ALIGN(pt->len);
83 if (attrlen < NLA_ALIGN(pt->len) + NLA_HDRLEN + nla_len(nla))
84 return -ERANGE;
85 break;
86 case NLA_NESTED:
87 /* a nested attributes is allowed to be empty; if its not,
88 * it must have a size of at least NLA_HDRLEN.
89 */
90 if (attrlen == 0)
91 break;
92 default:
93 if (pt->len)
94 minlen = pt->len;
95 else if (pt->type != NLA_UNSPEC)
96 minlen = nla_attr_minlen[pt->type];
97
98 if (attrlen < minlen)
99 return -ERANGE;
100 }
101
102 return 0;
103}
104
105/**
106 * nla_validate - Validate a stream of attributes
107 * @head: head of attribute stream
108 * @len: length of attribute stream
109 * @maxtype: maximum attribute type to be expected
110 * @policy: validation policy
111 *
112 * Validates all attributes in the specified attribute stream against the
113 * specified policy. Attributes with a type exceeding maxtype will be
114 * ignored. See documenation of struct nla_policy for more details.
115 *
116 * Returns 0 on success or a negative error code.
117 */
118int nla_validate(struct nlattr *head, int len, int maxtype,
119 const struct nla_policy *policy)
120{
121 struct nlattr *nla;
122 int rem, err;
123
124 nla_for_each_attr(nla, head, len, rem) {
125 err = validate_nla(nla, maxtype, policy);
126 if (err < 0)
127 goto errout;
128 }
129
130 err = 0;
131errout:
132 return err;
133}
134
135/**
136 * nla_parse - Parse a stream of attributes into a tb buffer
137 * @tb: destination array with maxtype+1 elements
138 * @maxtype: maximum attribute type to be expected
139 * @head: head of attribute stream
140 * @len: length of attribute stream
141 * @policy: validation policy
142 *
143 * Parses a stream of attributes and stores a pointer to each attribute in
144 * the tb array accessable via the attribute type. Attributes with a type
145 * exceeding maxtype will be silently ignored for backwards compatibility
146 * reasons. policy may be set to NULL if no validation is required.
147 *
148 * Returns 0 on success or a negative error code.
149 */
150int nla_parse(struct nlattr *tb[], int maxtype, struct nlattr *head, int len,
151 const struct nla_policy *policy)
152{
153 struct nlattr *nla;
154 int rem, err;
155
156 memset(tb, 0, sizeof(struct nlattr *) * (maxtype + 1));
157
158 nla_for_each_attr(nla, head, len, rem) {
159 u16 type = nla_type(nla);
160
161 if (type > 0 && type <= maxtype) {
162 if (policy) {
163 err = validate_nla(nla, maxtype, policy);
164 if (err < 0)
165 goto errout;
166 }
167
168 tb[type] = nla;
169 }
170 }
171
172 if (unlikely(rem > 0))
173 printk(KERN_WARNING "netlink: %d bytes leftover after parsing "
174 "attributes.\n", rem);
175
176 err = 0;
177errout:
178 return err;
179}
180
181/**
182 * nla_find - Find a specific attribute in a stream of attributes
183 * @head: head of attribute stream
184 * @len: length of attribute stream
185 * @attrtype: type of attribute to look for
186 *
187 * Returns the first attribute in the stream matching the specified type.
188 */
189struct nlattr *nla_find(struct nlattr *head, int len, int attrtype)
190{
191 struct nlattr *nla;
192 int rem;
193
194 nla_for_each_attr(nla, head, len, rem)
195 if (nla_type(nla) == attrtype)
196 return nla;
197
198 return NULL;
199}
200
201/**
202 * nla_strlcpy - Copy string attribute payload into a sized buffer
203 * @dst: where to copy the string to
204 * @nla: attribute to copy the string from
205 * @dstsize: size of destination buffer
206 *
207 * Copies at most dstsize - 1 bytes into the destination buffer.
208 * The result is always a valid NUL-terminated string. Unlike
209 * strlcpy the destination buffer is always padded out.
210 *
211 * Returns the length of the source buffer.
212 */
213size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
214{
215 size_t srclen = nla_len(nla);
216 char *src = nla_data(nla);
217
218 if (srclen > 0 && src[srclen - 1] == '\0')
219 srclen--;
220
221 if (dstsize > 0) {
222 size_t len = (srclen >= dstsize) ? dstsize - 1 : srclen;
223
224 memset(dst, 0, dstsize);
225 memcpy(dst, src, len);
226 }
227
228 return srclen;
229}
230
231/**
232 * nla_memcpy - Copy a netlink attribute into another memory area
233 * @dest: where to copy to memcpy
234 * @src: netlink attribute to copy from
235 * @count: size of the destination area
236 *
237 * Note: The number of bytes copied is limited by the length of
238 * attribute's payload. memcpy
239 *
240 * Returns the number of bytes copied.
241 */
242int nla_memcpy(void *dest, const struct nlattr *src, int count)
243{
244 int minlen = min_t(int, count, nla_len(src));
245
246 memcpy(dest, nla_data(src), minlen);
247
248 return minlen;
249}
250
251/**
252 * nla_memcmp - Compare an attribute with sized memory area
253 * @nla: netlink attribute
254 * @data: memory area
255 * @size: size of memory area
256 */
257int nla_memcmp(const struct nlattr *nla, const void *data,
258 size_t size)
259{
260 int d = nla_len(nla) - size;
261
262 if (d == 0)
263 d = memcmp(nla_data(nla), data, size);
264
265 return d;
266}
267
268/**
269 * nla_strcmp - Compare a string attribute against a string
270 * @nla: netlink string attribute
271 * @str: another string
272 */
273int nla_strcmp(const struct nlattr *nla, const char *str)
274{
275 int len = strlen(str) + 1;
276 int d = nla_len(nla) - len;
277
278 if (d == 0)
279 d = memcmp(nla_data(nla), str, len);
280
281 return d;
282}
283
284/**
285 * __nla_reserve - reserve room for attribute on the skb
286 * @skb: socket buffer to reserve room on
287 * @attrtype: attribute type
288 * @attrlen: length of attribute payload
289 *
290 * Adds a netlink attribute header to a socket buffer and reserves
291 * room for the payload but does not copy it.
292 *
293 * The caller is responsible to ensure that the skb provides enough
294 * tailroom for the attribute header and payload.
295 */
296struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
297{
298 struct nlattr *nla;
299
300 nla = (struct nlattr *) skb_put(skb, nla_total_size(attrlen));
301 nla->nla_type = attrtype;
302 nla->nla_len = nla_attr_size(attrlen);
303
304 memset((unsigned char *) nla + nla->nla_len, 0, nla_padlen(attrlen));
305
306 return nla;
307}
308
309/**
310 * __nla_reserve_nohdr - reserve room for attribute without header
311 * @skb: socket buffer to reserve room on
312 * @attrlen: length of attribute payload
313 *
314 * Reserves room for attribute payload without a header.
315 *
316 * The caller is responsible to ensure that the skb provides enough
317 * tailroom for the payload.
318 */
319void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
320{
321 void *start;
322
323 start = skb_put(skb, NLA_ALIGN(attrlen));
324 memset(start, 0, NLA_ALIGN(attrlen));
325
326 return start;
327}
328
329/**
330 * nla_reserve - reserve room for attribute on the skb
331 * @skb: socket buffer to reserve room on
332 * @attrtype: attribute type
333 * @attrlen: length of attribute payload
334 *
335 * Adds a netlink attribute header to a socket buffer and reserves
336 * room for the payload but does not copy it.
337 *
338 * Returns NULL if the tailroom of the skb is insufficient to store
339 * the attribute header and payload.
340 */
341struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
342{
343 if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen)))
344 return NULL;
345
346 return __nla_reserve(skb, attrtype, attrlen);
347}
348
349/**
350 * nla_reserve_nohdr - reserve room for attribute without header
351 * @skb: socket buffer to reserve room on
352 * @attrlen: length of attribute payload
353 *
354 * Reserves room for attribute payload without a header.
355 *
356 * Returns NULL if the tailroom of the skb is insufficient to store
357 * the attribute payload.
358 */
359void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
360{
361 if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
362 return NULL;
363
364 return __nla_reserve_nohdr(skb, attrlen);
365}
366
367/**
368 * __nla_put - Add a netlink attribute to a socket buffer
369 * @skb: socket buffer to add attribute to
370 * @attrtype: attribute type
371 * @attrlen: length of attribute payload
372 * @data: head of attribute payload
373 *
374 * The caller is responsible to ensure that the skb provides enough
375 * tailroom for the attribute header and payload.
376 */
377void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
378 const void *data)
379{
380 struct nlattr *nla;
381
382 nla = __nla_reserve(skb, attrtype, attrlen);
383 memcpy(nla_data(nla), data, attrlen);
384}
385
386/**
387 * __nla_put_nohdr - Add a netlink attribute without header
388 * @skb: socket buffer to add attribute to
389 * @attrlen: length of attribute payload
390 * @data: head of attribute payload
391 *
392 * The caller is responsible to ensure that the skb provides enough
393 * tailroom for the attribute payload.
394 */
395void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data)
396{
397 void *start;
398
399 start = __nla_reserve_nohdr(skb, attrlen);
400 memcpy(start, data, attrlen);
401}
402
403/**
404 * nla_put - Add a netlink attribute to a socket buffer
405 * @skb: socket buffer to add attribute to
406 * @attrtype: attribute type
407 * @attrlen: length of attribute payload
408 * @data: head of attribute payload
409 *
410 * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
411 * the attribute header and payload.
412 */
413int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
414{
415 if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen)))
416 return -EMSGSIZE;
417
418 __nla_put(skb, attrtype, attrlen, data);
419 return 0;
420}
421
422/**
423 * nla_put_nohdr - Add a netlink attribute without header
424 * @skb: socket buffer to add attribute to
425 * @attrlen: length of attribute payload
426 * @data: head of attribute payload
427 *
428 * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
429 * the attribute payload.
430 */
431int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data)
432{
433 if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
434 return -EMSGSIZE;
435
436 __nla_put_nohdr(skb, attrlen, data);
437 return 0;
438}
439
440/**
441 * nla_append - Add a netlink attribute without header or padding
442 * @skb: socket buffer to add attribute to
443 * @attrlen: length of attribute payload
444 * @data: head of attribute payload
445 *
446 * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
447 * the attribute payload.
448 */
449int nla_append(struct sk_buff *skb, int attrlen, const void *data)
450{
451 if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
452 return -EMSGSIZE;
453
454 memcpy(skb_put(skb, attrlen), data, attrlen);
455 return 0;
456}
457
458EXPORT_SYMBOL(nla_validate);
459EXPORT_SYMBOL(nla_parse);
460EXPORT_SYMBOL(nla_find);
461EXPORT_SYMBOL(nla_strlcpy);
462EXPORT_SYMBOL(__nla_reserve);
463EXPORT_SYMBOL(__nla_reserve_nohdr);
464EXPORT_SYMBOL(nla_reserve);
465EXPORT_SYMBOL(nla_reserve_nohdr);
466EXPORT_SYMBOL(__nla_put);
467EXPORT_SYMBOL(__nla_put_nohdr);
468EXPORT_SYMBOL(nla_put);
469EXPORT_SYMBOL(nla_put_nohdr);
470EXPORT_SYMBOL(nla_memcpy);
471EXPORT_SYMBOL(nla_memcmp);
472EXPORT_SYMBOL(nla_strcmp);
473EXPORT_SYMBOL(nla_append);
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-13 03:53:59 -0500