Loading...
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/system.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 {
64 l <<= 8;
65 if (*str != '\0')
66 {
67 val = 0;
68 while (*str != '\0' && *str != '.' && *str != '\n')
69 {
70 val *= 10;
71 val += *str - '0';
72 str++;
73 }
74 l |= val;
75 if (*str != '\0')
76 str++;
77 }
78 }
79 return htonl(l);
80}
81EXPORT_SYMBOL(in_aton);
82
83#define IN6PTON_XDIGIT 0x00010000
84#define IN6PTON_DIGIT 0x00020000
85#define IN6PTON_COLON_MASK 0x00700000
86#define IN6PTON_COLON_1 0x00100000 /* single : requested */
87#define IN6PTON_COLON_2 0x00200000 /* second : requested */
88#define IN6PTON_COLON_1_2 0x00400000 /* :: requested */
89#define IN6PTON_DOT 0x00800000 /* . */
90#define IN6PTON_DELIM 0x10000000
91#define IN6PTON_NULL 0x20000000 /* first/tail */
92#define IN6PTON_UNKNOWN 0x40000000
93
94static inline int xdigit2bin(char c, int delim)
95{
96 int val;
97
98 if (c == delim || c == '\0')
99 return IN6PTON_DELIM;
100 if (c == ':')
101 return IN6PTON_COLON_MASK;
102 if (c == '.')
103 return IN6PTON_DOT;
104
105 val = hex_to_bin(c);
106 if (val >= 0)
107 return val | IN6PTON_XDIGIT | (val < 10 ? IN6PTON_DIGIT : 0);
108
109 if (delim == -1)
110 return IN6PTON_DELIM;
111 return IN6PTON_UNKNOWN;
112}
113
114int in4_pton(const char *src, int srclen,
115 u8 *dst,
116 int delim, const char **end)
117{
118 const char *s;
119 u8 *d;
120 u8 dbuf[4];
121 int ret = 0;
122 int i;
123 int w = 0;
124
125 if (srclen < 0)
126 srclen = strlen(src);
127 s = src;
128 d = dbuf;
129 i = 0;
130 while(1) {
131 int c;
132 c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
133 if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK))) {
134 goto out;
135 }
136 if (c & (IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
137 if (w == 0)
138 goto out;
139 *d++ = w & 0xff;
140 w = 0;
141 i++;
142 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
143 if (i != 4)
144 goto out;
145 break;
146 }
147 goto cont;
148 }
149 w = (w * 10) + c;
150 if ((w & 0xffff) > 255) {
151 goto out;
152 }
153cont:
154 if (i >= 4)
155 goto out;
156 s++;
157 srclen--;
158 }
159 ret = 1;
160 memcpy(dst, dbuf, sizeof(dbuf));
161out:
162 if (end)
163 *end = s;
164 return ret;
165}
166EXPORT_SYMBOL(in4_pton);
167
168int in6_pton(const char *src, int srclen,
169 u8 *dst,
170 int delim, const char **end)
171{
172 const char *s, *tok = NULL;
173 u8 *d, *dc = NULL;
174 u8 dbuf[16];
175 int ret = 0;
176 int i;
177 int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL;
178 int w = 0;
179
180 memset(dbuf, 0, sizeof(dbuf));
181
182 s = src;
183 d = dbuf;
184 if (srclen < 0)
185 srclen = strlen(src);
186
187 while (1) {
188 int c;
189
190 c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
191 if (!(c & state))
192 goto out;
193 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
194 /* process one 16-bit word */
195 if (!(state & IN6PTON_NULL)) {
196 *d++ = (w >> 8) & 0xff;
197 *d++ = w & 0xff;
198 }
199 w = 0;
200 if (c & IN6PTON_DELIM) {
201 /* We've processed last word */
202 break;
203 }
204 /*
205 * COLON_1 => XDIGIT
206 * COLON_2 => XDIGIT|DELIM
207 * COLON_1_2 => COLON_2
208 */
209 switch (state & IN6PTON_COLON_MASK) {
210 case IN6PTON_COLON_2:
211 dc = d;
212 state = IN6PTON_XDIGIT | IN6PTON_DELIM;
213 if (dc - dbuf >= sizeof(dbuf))
214 state |= IN6PTON_NULL;
215 break;
216 case IN6PTON_COLON_1|IN6PTON_COLON_1_2:
217 state = IN6PTON_XDIGIT | IN6PTON_COLON_2;
218 break;
219 case IN6PTON_COLON_1:
220 state = IN6PTON_XDIGIT;
221 break;
222 case IN6PTON_COLON_1_2:
223 state = IN6PTON_COLON_2;
224 break;
225 default:
226 state = 0;
227 }
228 tok = s + 1;
229 goto cont;
230 }
231
232 if (c & IN6PTON_DOT) {
233 ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
234 if (ret > 0) {
235 d += 4;
236 break;
237 }
238 goto out;
239 }
240
241 w = (w << 4) | (0xff & c);
242 state = IN6PTON_COLON_1 | IN6PTON_DELIM;
243 if (!(w & 0xf000)) {
244 state |= IN6PTON_XDIGIT;
245 }
246 if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
247 state |= IN6PTON_COLON_1_2;
248 state &= ~IN6PTON_DELIM;
249 }
250 if (d + 2 >= dbuf + sizeof(dbuf)) {
251 state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2);
252 }
253cont:
254 if ((dc && d + 4 < dbuf + sizeof(dbuf)) ||
255 d + 4 == dbuf + sizeof(dbuf)) {
256 state |= IN6PTON_DOT;
257 }
258 if (d >= dbuf + sizeof(dbuf)) {
259 state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK);
260 }
261 s++;
262 srclen--;
263 }
264
265 i = 15; d--;
266
267 if (dc) {
268 while(d >= dc)
269 dst[i--] = *d--;
270 while(i >= dc - dbuf)
271 dst[i--] = 0;
272 while(i >= 0)
273 dst[i--] = *d--;
274 } else
275 memcpy(dst, dbuf, sizeof(dbuf));
276
277 ret = 1;
278out:
279 if (end)
280 *end = s;
281 return ret;
282}
283EXPORT_SYMBOL(in6_pton);
284
285void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
286 __be32 from, __be32 to, int pseudohdr)
287{
288 __be32 diff[] = { ~from, to };
289 if (skb->ip_summed != CHECKSUM_PARTIAL) {
290 *sum = csum_fold(csum_partial(diff, sizeof(diff),
291 ~csum_unfold(*sum)));
292 if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
293 skb->csum = ~csum_partial(diff, sizeof(diff),
294 ~skb->csum);
295 } else if (pseudohdr)
296 *sum = ~csum_fold(csum_partial(diff, sizeof(diff),
297 csum_unfold(*sum)));
298}
299EXPORT_SYMBOL(inet_proto_csum_replace4);
300
301int mac_pton(const char *s, u8 *mac)
302{
303 int i;
304
305 /* XX:XX:XX:XX:XX:XX */
306 if (strlen(s) < 3 * ETH_ALEN - 1)
307 return 0;
308
309 /* Don't dirty result unless string is valid MAC. */
310 for (i = 0; i < ETH_ALEN; i++) {
311 if (!strchr("0123456789abcdefABCDEF", s[i * 3]))
312 return 0;
313 if (!strchr("0123456789abcdefABCDEF", s[i * 3 + 1]))
314 return 0;
315 if (i != ETH_ALEN - 1 && s[i * 3 + 2] != ':')
316 return 0;
317 }
318 for (i = 0; i < ETH_ALEN; i++) {
319 mac[i] = (hex_to_bin(s[i * 3]) << 4) | hex_to_bin(s[i * 3 + 1]);
320 }
321 return 1;
322}
323EXPORT_SYMBOL(mac_pton);