blob: 3dffce953c39fc0209e8d0f553817e972f854303 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Generic address resultion entity
3 *
4 * Authors:
5 * net_random Alan Cox
Steven Rostedt75b31c32006-09-27 22:55:39 -07006 * net_ratelimit Andi Kleen
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +09007 * in{4,6}_pton YOSHIFUJI Hideaki, Copyright (C)2006 USAGI/WIDE Project
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 *
9 * Created by Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
15 */
16
17#include <linux/module.h>
18#include <linux/jiffies.h>
19#include <linux/kernel.h>
Andy Shevchenko5a048e32013-03-27 05:54:13 +000020#include <linux/ctype.h>
Arnaldo Carvalho de Melo20380732005-08-16 02:18:02 -030021#include <linux/inet.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/mm.h>
Arnaldo Carvalho de Melo20380732005-08-16 02:18:02 -030023#include <linux/net.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/string.h>
25#include <linux/types.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/percpu.h>
27#include <linux/init.h>
Ingo Molnar3fff4c42009-09-22 16:18:09 +020028#include <linux/ratelimit.h>
29
Johannes Berg14ae8562007-08-07 18:02:43 -070030#include <net/sock.h>
David S. Millerc5c177b2011-05-27 13:41:33 -040031#include <net/net_ratelimit.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032
Matt Mackall5e43db72005-07-27 15:24:42 -070033#include <asm/byteorder.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <asm/uaccess.h>
35
Dave Young717115e2008-07-25 01:45:58 -070036DEFINE_RATELIMIT_STATE(net_ratelimit_state, 5 * HZ, 10);
YOSHIFUJI Hideaki4ec93ed2007-02-09 23:24:36 +090037/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070038 * All net warning printk()s should be guarded by this function.
YOSHIFUJI Hideaki4ec93ed2007-02-09 23:24:36 +090039 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070040int net_ratelimit(void)
41{
Dave Young717115e2008-07-25 01:45:58 -070042 return __ratelimit(&net_ratelimit_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -070043}
Linus Torvalds1da177e2005-04-16 15:20:36 -070044EXPORT_SYMBOL(net_ratelimit);
Matt Mackall5e43db72005-07-27 15:24:42 -070045
46/*
47 * Convert an ASCII string to binary IP.
48 * This is outside of net/ipv4/ because various code that uses IP addresses
49 * is otherwise not dependent on the TCP/IP stack.
50 */
51
Alexey Dobriyana2167dc2006-01-06 13:24:54 -080052__be32 in_aton(const char *str)
Matt Mackall5e43db72005-07-27 15:24:42 -070053{
54 unsigned long l;
55 unsigned int val;
56 int i;
57
58 l = 0;
Jeffrin Jose46ba5b22012-04-08 06:07:42 +000059 for (i = 0; i < 4; i++) {
Matt Mackall5e43db72005-07-27 15:24:42 -070060 l <<= 8;
Jeffrin Jose46ba5b22012-04-08 06:07:42 +000061 if (*str != '\0') {
Matt Mackall5e43db72005-07-27 15:24:42 -070062 val = 0;
Jeffrin Jose46ba5b22012-04-08 06:07:42 +000063 while (*str != '\0' && *str != '.' && *str != '\n') {
Matt Mackall5e43db72005-07-27 15:24:42 -070064 val *= 10;
65 val += *str - '0';
66 str++;
67 }
68 l |= val;
69 if (*str != '\0')
70 str++;
71 }
72 }
Eric Dumazeta02cec22010-09-22 20:43:57 +000073 return htonl(l);
Matt Mackall5e43db72005-07-27 15:24:42 -070074}
Matt Mackall5e43db72005-07-27 15:24:42 -070075EXPORT_SYMBOL(in_aton);
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +090076
77#define IN6PTON_XDIGIT 0x00010000
78#define IN6PTON_DIGIT 0x00020000
79#define IN6PTON_COLON_MASK 0x00700000
80#define IN6PTON_COLON_1 0x00100000 /* single : requested */
81#define IN6PTON_COLON_2 0x00200000 /* second : requested */
82#define IN6PTON_COLON_1_2 0x00400000 /* :: requested */
83#define IN6PTON_DOT 0x00800000 /* . */
84#define IN6PTON_DELIM 0x10000000
85#define IN6PTON_NULL 0x20000000 /* first/tail */
86#define IN6PTON_UNKNOWN 0x40000000
87
Patrick McHardy9a7c9332006-12-02 22:04:04 -080088static inline int xdigit2bin(char c, int delim)
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +090089{
Andy Shevchenko82fd5b52010-09-20 20:40:26 +000090 int val;
91
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +090092 if (c == delim || c == '\0')
93 return IN6PTON_DELIM;
94 if (c == ':')
95 return IN6PTON_COLON_MASK;
96 if (c == '.')
97 return IN6PTON_DOT;
Andy Shevchenko82fd5b52010-09-20 20:40:26 +000098
99 val = hex_to_bin(c);
100 if (val >= 0)
101 return val | IN6PTON_XDIGIT | (val < 10 ? IN6PTON_DIGIT : 0);
102
Patrick McHardy9a7c9332006-12-02 22:04:04 -0800103 if (delim == -1)
104 return IN6PTON_DELIM;
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900105 return IN6PTON_UNKNOWN;
106}
107
Amerigo Wang93ac0ef2012-10-11 21:06:17 +0000108/**
109 * in4_pton - convert an IPv4 address from literal to binary representation
110 * @src: the start of the IPv4 address string
111 * @srclen: the length of the string, -1 means strlen(src)
112 * @dst: the binary (u8[4] array) representation of the IPv4 address
113 * @delim: the delimiter of the IPv4 address in @src, -1 means no delimiter
114 * @end: A pointer to the end of the parsed string will be placed here
115 *
116 * Return one on success, return zero when any error occurs
117 * and @end will point to the end of the parsed string.
118 *
119 */
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900120int in4_pton(const char *src, int srclen,
121 u8 *dst,
Patrick McHardy9a7c9332006-12-02 22:04:04 -0800122 int delim, const char **end)
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900123{
124 const char *s;
125 u8 *d;
126 u8 dbuf[4];
127 int ret = 0;
128 int i;
129 int w = 0;
130
131 if (srclen < 0)
132 srclen = strlen(src);
133 s = src;
134 d = dbuf;
135 i = 0;
136 while(1) {
137 int c;
138 c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
Jerome Borsboom83f03fa2007-05-29 12:59:54 -0700139 if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK))) {
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900140 goto out;
141 }
Jerome Borsboom83f03fa2007-05-29 12:59:54 -0700142 if (c & (IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900143 if (w == 0)
144 goto out;
145 *d++ = w & 0xff;
146 w = 0;
147 i++;
Jerome Borsboom83f03fa2007-05-29 12:59:54 -0700148 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900149 if (i != 4)
150 goto out;
151 break;
152 }
153 goto cont;
154 }
155 w = (w * 10) + c;
156 if ((w & 0xffff) > 255) {
157 goto out;
158 }
159cont:
160 if (i >= 4)
161 goto out;
162 s++;
163 srclen--;
164 }
165 ret = 1;
166 memcpy(dst, dbuf, sizeof(dbuf));
167out:
168 if (end)
169 *end = s;
170 return ret;
171}
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900172EXPORT_SYMBOL(in4_pton);
173
Amerigo Wang28194fc2012-10-11 21:06:16 +0000174/**
175 * in6_pton - convert an IPv6 address from literal to binary representation
176 * @src: the start of the IPv6 address string
177 * @srclen: the length of the string, -1 means strlen(src)
178 * @dst: the binary (u8[16] array) representation of the IPv6 address
179 * @delim: the delimiter of the IPv6 address in @src, -1 means no delimiter
180 * @end: A pointer to the end of the parsed string will be placed here
181 *
182 * Return one on success, return zero when any error occurs
183 * and @end will point to the end of the parsed string.
184 *
185 */
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900186int in6_pton(const char *src, int srclen,
187 u8 *dst,
Patrick McHardy9a7c9332006-12-02 22:04:04 -0800188 int delim, const char **end)
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900189{
190 const char *s, *tok = NULL;
191 u8 *d, *dc = NULL;
192 u8 dbuf[16];
193 int ret = 0;
194 int i;
195 int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL;
196 int w = 0;
197
198 memset(dbuf, 0, sizeof(dbuf));
199
200 s = src;
201 d = dbuf;
202 if (srclen < 0)
203 srclen = strlen(src);
204
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900205 while (1) {
206 int c;
207
208 c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
209 if (!(c & state))
210 goto out;
211 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
212 /* process one 16-bit word */
213 if (!(state & IN6PTON_NULL)) {
214 *d++ = (w >> 8) & 0xff;
215 *d++ = w & 0xff;
216 }
217 w = 0;
218 if (c & IN6PTON_DELIM) {
219 /* We've processed last word */
220 break;
221 }
222 /*
223 * COLON_1 => XDIGIT
224 * COLON_2 => XDIGIT|DELIM
225 * COLON_1_2 => COLON_2
226 */
227 switch (state & IN6PTON_COLON_MASK) {
228 case IN6PTON_COLON_2:
229 dc = d;
230 state = IN6PTON_XDIGIT | IN6PTON_DELIM;
231 if (dc - dbuf >= sizeof(dbuf))
232 state |= IN6PTON_NULL;
233 break;
234 case IN6PTON_COLON_1|IN6PTON_COLON_1_2:
235 state = IN6PTON_XDIGIT | IN6PTON_COLON_2;
236 break;
237 case IN6PTON_COLON_1:
238 state = IN6PTON_XDIGIT;
239 break;
240 case IN6PTON_COLON_1_2:
241 state = IN6PTON_COLON_2;
242 break;
243 default:
244 state = 0;
245 }
246 tok = s + 1;
247 goto cont;
248 }
249
250 if (c & IN6PTON_DOT) {
251 ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
252 if (ret > 0) {
253 d += 4;
254 break;
255 }
256 goto out;
257 }
258
259 w = (w << 4) | (0xff & c);
260 state = IN6PTON_COLON_1 | IN6PTON_DELIM;
261 if (!(w & 0xf000)) {
262 state |= IN6PTON_XDIGIT;
263 }
264 if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
265 state |= IN6PTON_COLON_1_2;
266 state &= ~IN6PTON_DELIM;
267 }
268 if (d + 2 >= dbuf + sizeof(dbuf)) {
269 state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2);
270 }
271cont:
272 if ((dc && d + 4 < dbuf + sizeof(dbuf)) ||
273 d + 4 == dbuf + sizeof(dbuf)) {
274 state |= IN6PTON_DOT;
275 }
276 if (d >= dbuf + sizeof(dbuf)) {
277 state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK);
278 }
279 s++;
280 srclen--;
281 }
282
283 i = 15; d--;
284
285 if (dc) {
286 while(d >= dc)
287 dst[i--] = *d--;
288 while(i >= dc - dbuf)
289 dst[i--] = 0;
290 while(i >= 0)
291 dst[i--] = *d--;
292 } else
293 memcpy(dst, dbuf, sizeof(dbuf));
294
295 ret = 1;
296out:
297 if (end)
298 *end = s;
299 return ret;
300}
YOSHIFUJI Hideaki1aaec672006-06-25 23:54:55 +0900301EXPORT_SYMBOL(in6_pton);
Patrick McHardya99a00c2007-11-30 01:14:30 +1100302
303void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
Tom Herbert4b048d62015-08-17 13:42:25 -0700304 __be32 from, __be32 to, bool pseudohdr)
Patrick McHardya99a00c2007-11-30 01:14:30 +1100305{
Patrick McHardya99a00c2007-11-30 01:14:30 +1100306 if (skb->ip_summed != CHECKSUM_PARTIAL) {
Eric Dumazet05c98542015-05-25 18:50:01 -0700307 csum_replace4(sum, from, to);
Patrick McHardya99a00c2007-11-30 01:14:30 +1100308 if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
Eric Dumazet05c98542015-05-25 18:50:01 -0700309 skb->csum = ~csum_add(csum_sub(~(skb->csum),
310 (__force __wsum)from),
311 (__force __wsum)to);
Patrick McHardya99a00c2007-11-30 01:14:30 +1100312 } else if (pseudohdr)
Eric Dumazet05c98542015-05-25 18:50:01 -0700313 *sum = ~csum_fold(csum_add(csum_sub(csum_unfold(*sum),
314 (__force __wsum)from),
315 (__force __wsum)to));
Patrick McHardya99a00c2007-11-30 01:14:30 +1100316}
317EXPORT_SYMBOL(inet_proto_csum_replace4);
Alexey Dobriyan4940fc82011-05-07 23:00:07 +0000318
Patrick McHardy2cf545e2012-08-26 19:14:10 +0200319void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb,
320 const __be32 *from, const __be32 *to,
Tom Herbert4b048d62015-08-17 13:42:25 -0700321 bool pseudohdr)
Patrick McHardy2cf545e2012-08-26 19:14:10 +0200322{
323 __be32 diff[] = {
324 ~from[0], ~from[1], ~from[2], ~from[3],
325 to[0], to[1], to[2], to[3],
326 };
327 if (skb->ip_summed != CHECKSUM_PARTIAL) {
328 *sum = csum_fold(csum_partial(diff, sizeof(diff),
329 ~csum_unfold(*sum)));
330 if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
331 skb->csum = ~csum_partial(diff, sizeof(diff),
332 ~skb->csum);
333 } else if (pseudohdr)
334 *sum = ~csum_fold(csum_partial(diff, sizeof(diff),
335 csum_unfold(*sum)));
336}
337EXPORT_SYMBOL(inet_proto_csum_replace16);
Hannes Frederic Sowaa48e4292013-10-19 21:48:55 +0200338
Tom Herbertabc5d1f2015-08-17 13:42:26 -0700339void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb,
340 __wsum diff, bool pseudohdr)
341{
342 if (skb->ip_summed != CHECKSUM_PARTIAL) {
343 *sum = csum_fold(csum_add(diff, ~csum_unfold(*sum)));
344 if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
345 skb->csum = ~csum_add(diff, ~skb->csum);
346 } else if (pseudohdr) {
347 *sum = ~csum_fold(csum_add(diff, csum_unfold(*sum)));
348 }
349}
350EXPORT_SYMBOL(inet_proto_csum_replace_by_diff);
351
Hannes Frederic Sowaa48e4292013-10-19 21:48:55 +0200352struct __net_random_once_work {
353 struct work_struct work;
354 struct static_key *key;
355};
356
357static void __net_random_once_deferred(struct work_struct *w)
358{
359 struct __net_random_once_work *work =
360 container_of(w, struct __net_random_once_work, work);
Hannes Frederic Sowa3d440522014-05-11 22:59:30 +0200361 BUG_ON(!static_key_enabled(work->key));
362 static_key_slow_dec(work->key);
Hannes Frederic Sowaa48e4292013-10-19 21:48:55 +0200363 kfree(work);
364}
365
366static void __net_random_once_disable_jump(struct static_key *key)
367{
368 struct __net_random_once_work *w;
369
370 w = kmalloc(sizeof(*w), GFP_ATOMIC);
371 if (!w)
372 return;
373
374 INIT_WORK(&w->work, __net_random_once_deferred);
375 w->key = key;
376 schedule_work(&w->work);
377}
378
379bool __net_get_random_once(void *buf, int nbytes, bool *done,
Hannes Frederic Sowa3d440522014-05-11 22:59:30 +0200380 struct static_key *once_key)
Hannes Frederic Sowaa48e4292013-10-19 21:48:55 +0200381{
382 static DEFINE_SPINLOCK(lock);
Hannes Frederic Sowaf84be2b2013-10-23 20:05:27 +0200383 unsigned long flags;
Hannes Frederic Sowaa48e4292013-10-19 21:48:55 +0200384
Hannes Frederic Sowaf84be2b2013-10-23 20:05:27 +0200385 spin_lock_irqsave(&lock, flags);
Hannes Frederic Sowaa48e4292013-10-19 21:48:55 +0200386 if (*done) {
Hannes Frederic Sowaf84be2b2013-10-23 20:05:27 +0200387 spin_unlock_irqrestore(&lock, flags);
Hannes Frederic Sowaa48e4292013-10-19 21:48:55 +0200388 return false;
389 }
390
391 get_random_bytes(buf, nbytes);
392 *done = true;
Hannes Frederic Sowaf84be2b2013-10-23 20:05:27 +0200393 spin_unlock_irqrestore(&lock, flags);
Hannes Frederic Sowaa48e4292013-10-19 21:48:55 +0200394
Hannes Frederic Sowa3d440522014-05-11 22:59:30 +0200395 __net_random_once_disable_jump(once_key);
Hannes Frederic Sowaa48e4292013-10-19 21:48:55 +0200396
397 return true;
398}
399EXPORT_SYMBOL(__net_get_random_once);