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1/*
2 * Generic address resultion entity
3 *
4 * Authors:
5 * net_random Alan Cox
6 * net_ratelimit Andi Kleen
7 * in{4,6}_pton YOSHIFUJI Hideaki, Copyright (C)2006 USAGI/WIDE Project
8 *
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>
20#include <linux/ctype.h>
21#include <linux/inet.h>
22#include <linux/mm.h>
23#include <linux/net.h>
24#include <linux/string.h>
25#include <linux/types.h>
26#include <linux/percpu.h>
27#include <linux/init.h>
28#include <linux/ratelimit.h>
29
30#include <net/sock.h>
31#include <net/net_ratelimit.h>
32
33#include <asm/byteorder.h>
34#include <asm/uaccess.h>
35
36int net_msg_warn __read_mostly = 1;
37EXPORT_SYMBOL(net_msg_warn);
38
39DEFINE_RATELIMIT_STATE(net_ratelimit_state, 5 * HZ, 10);
40/*
41 * All net warning printk()s should be guarded by this function.
42 */
43int net_ratelimit(void)
44{
45 return __ratelimit(&net_ratelimit_state);
46}
47EXPORT_SYMBOL(net_ratelimit);
48
49/*
50 * Convert an ASCII string to binary IP.
51 * This is outside of net/ipv4/ because various code that uses IP addresses
52 * is otherwise not dependent on the TCP/IP stack.
53 */
54
55__be32 in_aton(const char *str)
56{
57 unsigned long l;
58 unsigned int val;
59 int i;
60
61 l = 0;
62 for (i = 0; i < 4; i++) {
63 l <<= 8;
64 if (*str != '\0') {
65 val = 0;
66 while (*str != '\0' && *str != '.' && *str != '\n') {
67 val *= 10;
68 val += *str - '0';
69 str++;
70 }
71 l |= val;
72 if (*str != '\0')
73 str++;
74 }
75 }
76 return htonl(l);
77}
78EXPORT_SYMBOL(in_aton);
79
80#define IN6PTON_XDIGIT 0x00010000
81#define IN6PTON_DIGIT 0x00020000
82#define IN6PTON_COLON_MASK 0x00700000
83#define IN6PTON_COLON_1 0x00100000 /* single : requested */
84#define IN6PTON_COLON_2 0x00200000 /* second : requested */
85#define IN6PTON_COLON_1_2 0x00400000 /* :: requested */
86#define IN6PTON_DOT 0x00800000 /* . */
87#define IN6PTON_DELIM 0x10000000
88#define IN6PTON_NULL 0x20000000 /* first/tail */
89#define IN6PTON_UNKNOWN 0x40000000
90
91static inline int xdigit2bin(char c, int delim)
92{
93 int val;
94
95 if (c == delim || c == '\0')
96 return IN6PTON_DELIM;
97 if (c == ':')
98 return IN6PTON_COLON_MASK;
99 if (c == '.')
100 return IN6PTON_DOT;
101
102 val = hex_to_bin(c);
103 if (val >= 0)
104 return val | IN6PTON_XDIGIT | (val < 10 ? IN6PTON_DIGIT : 0);
105
106 if (delim == -1)
107 return IN6PTON_DELIM;
108 return IN6PTON_UNKNOWN;
109}
110
111/**
112 * in4_pton - convert an IPv4 address from literal to binary representation
113 * @src: the start of the IPv4 address string
114 * @srclen: the length of the string, -1 means strlen(src)
115 * @dst: the binary (u8[4] array) representation of the IPv4 address
116 * @delim: the delimiter of the IPv4 address in @src, -1 means no delimiter
117 * @end: A pointer to the end of the parsed string will be placed here
118 *
119 * Return one on success, return zero when any error occurs
120 * and @end will point to the end of the parsed string.
121 *
122 */
123int in4_pton(const char *src, int srclen,
124 u8 *dst,
125 int delim, const char **end)
126{
127 const char *s;
128 u8 *d;
129 u8 dbuf[4];
130 int ret = 0;
131 int i;
132 int w = 0;
133
134 if (srclen < 0)
135 srclen = strlen(src);
136 s = src;
137 d = dbuf;
138 i = 0;
139 while(1) {
140 int c;
141 c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
142 if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK))) {
143 goto out;
144 }
145 if (c & (IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
146 if (w == 0)
147 goto out;
148 *d++ = w & 0xff;
149 w = 0;
150 i++;
151 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
152 if (i != 4)
153 goto out;
154 break;
155 }
156 goto cont;
157 }
158 w = (w * 10) + c;
159 if ((w & 0xffff) > 255) {
160 goto out;
161 }
162cont:
163 if (i >= 4)
164 goto out;
165 s++;
166 srclen--;
167 }
168 ret = 1;
169 memcpy(dst, dbuf, sizeof(dbuf));
170out:
171 if (end)
172 *end = s;
173 return ret;
174}
175EXPORT_SYMBOL(in4_pton);
176
177/**
178 * in6_pton - convert an IPv6 address from literal to binary representation
179 * @src: the start of the IPv6 address string
180 * @srclen: the length of the string, -1 means strlen(src)
181 * @dst: the binary (u8[16] array) representation of the IPv6 address
182 * @delim: the delimiter of the IPv6 address in @src, -1 means no delimiter
183 * @end: A pointer to the end of the parsed string will be placed here
184 *
185 * Return one on success, return zero when any error occurs
186 * and @end will point to the end of the parsed string.
187 *
188 */
189int in6_pton(const char *src, int srclen,
190 u8 *dst,
191 int delim, const char **end)
192{
193 const char *s, *tok = NULL;
194 u8 *d, *dc = NULL;
195 u8 dbuf[16];
196 int ret = 0;
197 int i;
198 int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL;
199 int w = 0;
200
201 memset(dbuf, 0, sizeof(dbuf));
202
203 s = src;
204 d = dbuf;
205 if (srclen < 0)
206 srclen = strlen(src);
207
208 while (1) {
209 int c;
210
211 c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
212 if (!(c & state))
213 goto out;
214 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
215 /* process one 16-bit word */
216 if (!(state & IN6PTON_NULL)) {
217 *d++ = (w >> 8) & 0xff;
218 *d++ = w & 0xff;
219 }
220 w = 0;
221 if (c & IN6PTON_DELIM) {
222 /* We've processed last word */
223 break;
224 }
225 /*
226 * COLON_1 => XDIGIT
227 * COLON_2 => XDIGIT|DELIM
228 * COLON_1_2 => COLON_2
229 */
230 switch (state & IN6PTON_COLON_MASK) {
231 case IN6PTON_COLON_2:
232 dc = d;
233 state = IN6PTON_XDIGIT | IN6PTON_DELIM;
234 if (dc - dbuf >= sizeof(dbuf))
235 state |= IN6PTON_NULL;
236 break;
237 case IN6PTON_COLON_1|IN6PTON_COLON_1_2:
238 state = IN6PTON_XDIGIT | IN6PTON_COLON_2;
239 break;
240 case IN6PTON_COLON_1:
241 state = IN6PTON_XDIGIT;
242 break;
243 case IN6PTON_COLON_1_2:
244 state = IN6PTON_COLON_2;
245 break;
246 default:
247 state = 0;
248 }
249 tok = s + 1;
250 goto cont;
251 }
252
253 if (c & IN6PTON_DOT) {
254 ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
255 if (ret > 0) {
256 d += 4;
257 break;
258 }
259 goto out;
260 }
261
262 w = (w << 4) | (0xff & c);
263 state = IN6PTON_COLON_1 | IN6PTON_DELIM;
264 if (!(w & 0xf000)) {
265 state |= IN6PTON_XDIGIT;
266 }
267 if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
268 state |= IN6PTON_COLON_1_2;
269 state &= ~IN6PTON_DELIM;
270 }
271 if (d + 2 >= dbuf + sizeof(dbuf)) {
272 state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2);
273 }
274cont:
275 if ((dc && d + 4 < dbuf + sizeof(dbuf)) ||
276 d + 4 == dbuf + sizeof(dbuf)) {
277 state |= IN6PTON_DOT;
278 }
279 if (d >= dbuf + sizeof(dbuf)) {
280 state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK);
281 }
282 s++;
283 srclen--;
284 }
285
286 i = 15; d--;
287
288 if (dc) {
289 while(d >= dc)
290 dst[i--] = *d--;
291 while(i >= dc - dbuf)
292 dst[i--] = 0;
293 while(i >= 0)
294 dst[i--] = *d--;
295 } else
296 memcpy(dst, dbuf, sizeof(dbuf));
297
298 ret = 1;
299out:
300 if (end)
301 *end = s;
302 return ret;
303}
304EXPORT_SYMBOL(in6_pton);
305
306void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
307 __be32 from, __be32 to, int pseudohdr)
308{
309 __be32 diff[] = { ~from, to };
310 if (skb->ip_summed != CHECKSUM_PARTIAL) {
311 *sum = csum_fold(csum_partial(diff, sizeof(diff),
312 ~csum_unfold(*sum)));
313 if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
314 skb->csum = ~csum_partial(diff, sizeof(diff),
315 ~skb->csum);
316 } else if (pseudohdr)
317 *sum = ~csum_fold(csum_partial(diff, sizeof(diff),
318 csum_unfold(*sum)));
319}
320EXPORT_SYMBOL(inet_proto_csum_replace4);
321
322void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb,
323 const __be32 *from, const __be32 *to,
324 int pseudohdr)
325{
326 __be32 diff[] = {
327 ~from[0], ~from[1], ~from[2], ~from[3],
328 to[0], to[1], to[2], to[3],
329 };
330 if (skb->ip_summed != CHECKSUM_PARTIAL) {
331 *sum = csum_fold(csum_partial(diff, sizeof(diff),
332 ~csum_unfold(*sum)));
333 if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
334 skb->csum = ~csum_partial(diff, sizeof(diff),
335 ~skb->csum);
336 } else if (pseudohdr)
337 *sum = ~csum_fold(csum_partial(diff, sizeof(diff),
338 csum_unfold(*sum)));
339}
340EXPORT_SYMBOL(inet_proto_csum_replace16);
341
342struct __net_random_once_work {
343 struct work_struct work;
344 struct static_key *key;
345};
346
347static void __net_random_once_deferred(struct work_struct *w)
348{
349 struct __net_random_once_work *work =
350 container_of(w, struct __net_random_once_work, work);
351 BUG_ON(!static_key_enabled(work->key));
352 static_key_slow_dec(work->key);
353 kfree(work);
354}
355
356static void __net_random_once_disable_jump(struct static_key *key)
357{
358 struct __net_random_once_work *w;
359
360 w = kmalloc(sizeof(*w), GFP_ATOMIC);
361 if (!w)
362 return;
363
364 INIT_WORK(&w->work, __net_random_once_deferred);
365 w->key = key;
366 schedule_work(&w->work);
367}
368
369bool __net_get_random_once(void *buf, int nbytes, bool *done,
370 struct static_key *once_key)
371{
372 static DEFINE_SPINLOCK(lock);
373 unsigned long flags;
374
375 spin_lock_irqsave(&lock, flags);
376 if (*done) {
377 spin_unlock_irqrestore(&lock, flags);
378 return false;
379 }
380
381 get_random_bytes(buf, nbytes);
382 *done = true;
383 spin_unlock_irqrestore(&lock, flags);
384
385 __net_random_once_disable_jump(once_key);
386
387 return true;
388}
389EXPORT_SYMBOL(__net_get_random_once);
1/*
2 * Generic address resultion entity
3 *
4 * Authors:
5 * net_random Alan Cox
6 * net_ratelimit Andi Kleen
7 * in{4,6}_pton YOSHIFUJI Hideaki, Copyright (C)2006 USAGI/WIDE Project
8 *
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>
20#include <linux/inet.h>
21#include <linux/mm.h>
22#include <linux/net.h>
23#include <linux/string.h>
24#include <linux/types.h>
25#include <linux/percpu.h>
26#include <linux/init.h>
27#include <linux/ratelimit.h>
28
29#include <net/sock.h>
30#include <net/net_ratelimit.h>
31
32#include <asm/byteorder.h>
33#include <asm/uaccess.h>
34
35int net_msg_warn __read_mostly = 1;
36EXPORT_SYMBOL(net_msg_warn);
37
38DEFINE_RATELIMIT_STATE(net_ratelimit_state, 5 * HZ, 10);
39/*
40 * All net warning printk()s should be guarded by this function.
41 */
42int net_ratelimit(void)
43{
44 return __ratelimit(&net_ratelimit_state);
45}
46EXPORT_SYMBOL(net_ratelimit);
47
48/*
49 * Convert an ASCII string to binary IP.
50 * This is outside of net/ipv4/ because various code that uses IP addresses
51 * is otherwise not dependent on the TCP/IP stack.
52 */
53
54__be32 in_aton(const char *str)
55{
56 unsigned long l;
57 unsigned int val;
58 int i;
59
60 l = 0;
61 for (i = 0; i < 4; i++) {
62 l <<= 8;
63 if (*str != '\0') {
64 val = 0;
65 while (*str != '\0' && *str != '.' && *str != '\n') {
66 val *= 10;
67 val += *str - '0';
68 str++;
69 }
70 l |= val;
71 if (*str != '\0')
72 str++;
73 }
74 }
75 return htonl(l);
76}
77EXPORT_SYMBOL(in_aton);
78
79#define IN6PTON_XDIGIT 0x00010000
80#define IN6PTON_DIGIT 0x00020000
81#define IN6PTON_COLON_MASK 0x00700000
82#define IN6PTON_COLON_1 0x00100000 /* single : requested */
83#define IN6PTON_COLON_2 0x00200000 /* second : requested */
84#define IN6PTON_COLON_1_2 0x00400000 /* :: requested */
85#define IN6PTON_DOT 0x00800000 /* . */
86#define IN6PTON_DELIM 0x10000000
87#define IN6PTON_NULL 0x20000000 /* first/tail */
88#define IN6PTON_UNKNOWN 0x40000000
89
90static inline int xdigit2bin(char c, int delim)
91{
92 int val;
93
94 if (c == delim || c == '\0')
95 return IN6PTON_DELIM;
96 if (c == ':')
97 return IN6PTON_COLON_MASK;
98 if (c == '.')
99 return IN6PTON_DOT;
100
101 val = hex_to_bin(c);
102 if (val >= 0)
103 return val | IN6PTON_XDIGIT | (val < 10 ? IN6PTON_DIGIT : 0);
104
105 if (delim == -1)
106 return IN6PTON_DELIM;
107 return IN6PTON_UNKNOWN;
108}
109
110int in4_pton(const char *src, int srclen,
111 u8 *dst,
112 int delim, const char **end)
113{
114 const char *s;
115 u8 *d;
116 u8 dbuf[4];
117 int ret = 0;
118 int i;
119 int w = 0;
120
121 if (srclen < 0)
122 srclen = strlen(src);
123 s = src;
124 d = dbuf;
125 i = 0;
126 while(1) {
127 int c;
128 c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
129 if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK))) {
130 goto out;
131 }
132 if (c & (IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
133 if (w == 0)
134 goto out;
135 *d++ = w & 0xff;
136 w = 0;
137 i++;
138 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
139 if (i != 4)
140 goto out;
141 break;
142 }
143 goto cont;
144 }
145 w = (w * 10) + c;
146 if ((w & 0xffff) > 255) {
147 goto out;
148 }
149cont:
150 if (i >= 4)
151 goto out;
152 s++;
153 srclen--;
154 }
155 ret = 1;
156 memcpy(dst, dbuf, sizeof(dbuf));
157out:
158 if (end)
159 *end = s;
160 return ret;
161}
162EXPORT_SYMBOL(in4_pton);
163
164int in6_pton(const char *src, int srclen,
165 u8 *dst,
166 int delim, const char **end)
167{
168 const char *s, *tok = NULL;
169 u8 *d, *dc = NULL;
170 u8 dbuf[16];
171 int ret = 0;
172 int i;
173 int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL;
174 int w = 0;
175
176 memset(dbuf, 0, sizeof(dbuf));
177
178 s = src;
179 d = dbuf;
180 if (srclen < 0)
181 srclen = strlen(src);
182
183 while (1) {
184 int c;
185
186 c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
187 if (!(c & state))
188 goto out;
189 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
190 /* process one 16-bit word */
191 if (!(state & IN6PTON_NULL)) {
192 *d++ = (w >> 8) & 0xff;
193 *d++ = w & 0xff;
194 }
195 w = 0;
196 if (c & IN6PTON_DELIM) {
197 /* We've processed last word */
198 break;
199 }
200 /*
201 * COLON_1 => XDIGIT
202 * COLON_2 => XDIGIT|DELIM
203 * COLON_1_2 => COLON_2
204 */
205 switch (state & IN6PTON_COLON_MASK) {
206 case IN6PTON_COLON_2:
207 dc = d;
208 state = IN6PTON_XDIGIT | IN6PTON_DELIM;
209 if (dc - dbuf >= sizeof(dbuf))
210 state |= IN6PTON_NULL;
211 break;
212 case IN6PTON_COLON_1|IN6PTON_COLON_1_2:
213 state = IN6PTON_XDIGIT | IN6PTON_COLON_2;
214 break;
215 case IN6PTON_COLON_1:
216 state = IN6PTON_XDIGIT;
217 break;
218 case IN6PTON_COLON_1_2:
219 state = IN6PTON_COLON_2;
220 break;
221 default:
222 state = 0;
223 }
224 tok = s + 1;
225 goto cont;
226 }
227
228 if (c & IN6PTON_DOT) {
229 ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
230 if (ret > 0) {
231 d += 4;
232 break;
233 }
234 goto out;
235 }
236
237 w = (w << 4) | (0xff & c);
238 state = IN6PTON_COLON_1 | IN6PTON_DELIM;
239 if (!(w & 0xf000)) {
240 state |= IN6PTON_XDIGIT;
241 }
242 if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
243 state |= IN6PTON_COLON_1_2;
244 state &= ~IN6PTON_DELIM;
245 }
246 if (d + 2 >= dbuf + sizeof(dbuf)) {
247 state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2);
248 }
249cont:
250 if ((dc && d + 4 < dbuf + sizeof(dbuf)) ||
251 d + 4 == dbuf + sizeof(dbuf)) {
252 state |= IN6PTON_DOT;
253 }
254 if (d >= dbuf + sizeof(dbuf)) {
255 state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK);
256 }
257 s++;
258 srclen--;
259 }
260
261 i = 15; d--;
262
263 if (dc) {
264 while(d >= dc)
265 dst[i--] = *d--;
266 while(i >= dc - dbuf)
267 dst[i--] = 0;
268 while(i >= 0)
269 dst[i--] = *d--;
270 } else
271 memcpy(dst, dbuf, sizeof(dbuf));
272
273 ret = 1;
274out:
275 if (end)
276 *end = s;
277 return ret;
278}
279EXPORT_SYMBOL(in6_pton);
280
281void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
282 __be32 from, __be32 to, int pseudohdr)
283{
284 __be32 diff[] = { ~from, to };
285 if (skb->ip_summed != CHECKSUM_PARTIAL) {
286 *sum = csum_fold(csum_partial(diff, sizeof(diff),
287 ~csum_unfold(*sum)));
288 if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
289 skb->csum = ~csum_partial(diff, sizeof(diff),
290 ~skb->csum);
291 } else if (pseudohdr)
292 *sum = ~csum_fold(csum_partial(diff, sizeof(diff),
293 csum_unfold(*sum)));
294}
295EXPORT_SYMBOL(inet_proto_csum_replace4);
296
297int mac_pton(const char *s, u8 *mac)
298{
299 int i;
300
301 /* XX:XX:XX:XX:XX:XX */
302 if (strlen(s) < 3 * ETH_ALEN - 1)
303 return 0;
304
305 /* Don't dirty result unless string is valid MAC. */
306 for (i = 0; i < ETH_ALEN; i++) {
307 if (!strchr("0123456789abcdefABCDEF", s[i * 3]))
308 return 0;
309 if (!strchr("0123456789abcdefABCDEF", s[i * 3 + 1]))
310 return 0;
311 if (i != ETH_ALEN - 1 && s[i * 3 + 2] != ':')
312 return 0;
313 }
314 for (i = 0; i < ETH_ALEN; i++) {
315 mac[i] = (hex_to_bin(s[i * 3]) << 4) | hex_to_bin(s[i * 3 + 1]);
316 }
317 return 1;
318}
319EXPORT_SYMBOL(mac_pton);