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/random.h> 26 #include <linux/percpu.h> 27 #include <linux/init.h> 28 29 #include <asm/byteorder.h> 30 #include <asm/system.h> 31 #include <asm/uaccess.h> 32 33 int net_msg_cost = 5*HZ; 34 int net_msg_burst = 10; 35 36 /* 37 * All net warning printk()s should be guarded by this function. 38 */ 39 int net_ratelimit(void) 40 { 41 return __printk_ratelimit(net_msg_cost, net_msg_burst); 42 } 43 EXPORT_SYMBOL(net_ratelimit); 44 45 /* 46 * Convert an ASCII string to binary IP. 47 * This is outside of net/ipv4/ because various code that uses IP addresses 48 * is otherwise not dependent on the TCP/IP stack. 49 */ 50 51 __be32 in_aton(const char *str) 52 { 53 unsigned long l; 54 unsigned int val; 55 int i; 56 57 l = 0; 58 for (i = 0; i < 4; i++) 59 { 60 l <<= 8; 61 if (*str != '\0') 62 { 63 val = 0; 64 while (*str != '\0' && *str != '.' && *str != '\n') 65 { 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 } 77 78 EXPORT_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 91 static inline int digit2bin(char c, int delim) 92 { 93 if (c == delim || c == '\0') 94 return IN6PTON_DELIM; 95 if (c == '.') 96 return IN6PTON_DOT; 97 if (c >= '0' && c <= '9') 98 return (IN6PTON_DIGIT | (c - '0')); 99 return IN6PTON_UNKNOWN; 100 } 101 102 static inline int xdigit2bin(char c, int delim) 103 { 104 if (c == delim || c == '\0') 105 return IN6PTON_DELIM; 106 if (c == ':') 107 return IN6PTON_COLON_MASK; 108 if (c == '.') 109 return IN6PTON_DOT; 110 if (c >= '0' && c <= '9') 111 return (IN6PTON_XDIGIT | IN6PTON_DIGIT| (c - '0')); 112 if (c >= 'a' && c <= 'f') 113 return (IN6PTON_XDIGIT | (c - 'a' + 10)); 114 if (c >= 'A' && c <= 'F') 115 return (IN6PTON_XDIGIT | (c - 'A' + 10)); 116 if (delim == -1) 117 return IN6PTON_DELIM; 118 return IN6PTON_UNKNOWN; 119 } 120 121 int in4_pton(const char *src, int srclen, 122 u8 *dst, 123 int delim, const char **end) 124 { 125 const char *s; 126 u8 *d; 127 u8 dbuf[4]; 128 int ret = 0; 129 int i; 130 int w = 0; 131 132 if (srclen < 0) 133 srclen = strlen(src); 134 s = src; 135 d = dbuf; 136 i = 0; 137 while(1) { 138 int c; 139 c = xdigit2bin(srclen > 0 ? *s : '\0', delim); 140 if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM))) { 141 goto out; 142 } 143 if (c & (IN6PTON_DOT | IN6PTON_DELIM)) { 144 if (w == 0) 145 goto out; 146 *d++ = w & 0xff; 147 w = 0; 148 i++; 149 if (c & IN6PTON_DELIM) { 150 if (i != 4) 151 goto out; 152 break; 153 } 154 goto cont; 155 } 156 w = (w * 10) + c; 157 if ((w & 0xffff) > 255) { 158 goto out; 159 } 160 cont: 161 if (i >= 4) 162 goto out; 163 s++; 164 srclen--; 165 } 166 ret = 1; 167 memcpy(dst, dbuf, sizeof(dbuf)); 168 out: 169 if (end) 170 *end = s; 171 return ret; 172 } 173 174 EXPORT_SYMBOL(in4_pton); 175 176 int in6_pton(const char *src, int srclen, 177 u8 *dst, 178 int delim, const char **end) 179 { 180 const char *s, *tok = NULL; 181 u8 *d, *dc = NULL; 182 u8 dbuf[16]; 183 int ret = 0; 184 int i; 185 int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL; 186 int w = 0; 187 188 memset(dbuf, 0, sizeof(dbuf)); 189 190 s = src; 191 d = dbuf; 192 if (srclen < 0) 193 srclen = strlen(src); 194 195 while (1) { 196 int c; 197 198 c = xdigit2bin(srclen > 0 ? *s : '\0', delim); 199 if (!(c & state)) 200 goto out; 201 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) { 202 /* process one 16-bit word */ 203 if (!(state & IN6PTON_NULL)) { 204 *d++ = (w >> 8) & 0xff; 205 *d++ = w & 0xff; 206 } 207 w = 0; 208 if (c & IN6PTON_DELIM) { 209 /* We've processed last word */ 210 break; 211 } 212 /* 213 * COLON_1 => XDIGIT 214 * COLON_2 => XDIGIT|DELIM 215 * COLON_1_2 => COLON_2 216 */ 217 switch (state & IN6PTON_COLON_MASK) { 218 case IN6PTON_COLON_2: 219 dc = d; 220 state = IN6PTON_XDIGIT | IN6PTON_DELIM; 221 if (dc - dbuf >= sizeof(dbuf)) 222 state |= IN6PTON_NULL; 223 break; 224 case IN6PTON_COLON_1|IN6PTON_COLON_1_2: 225 state = IN6PTON_XDIGIT | IN6PTON_COLON_2; 226 break; 227 case IN6PTON_COLON_1: 228 state = IN6PTON_XDIGIT; 229 break; 230 case IN6PTON_COLON_1_2: 231 state = IN6PTON_COLON_2; 232 break; 233 default: 234 state = 0; 235 } 236 tok = s + 1; 237 goto cont; 238 } 239 240 if (c & IN6PTON_DOT) { 241 ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s); 242 if (ret > 0) { 243 d += 4; 244 break; 245 } 246 goto out; 247 } 248 249 w = (w << 4) | (0xff & c); 250 state = IN6PTON_COLON_1 | IN6PTON_DELIM; 251 if (!(w & 0xf000)) { 252 state |= IN6PTON_XDIGIT; 253 } 254 if (!dc && d + 2 < dbuf + sizeof(dbuf)) { 255 state |= IN6PTON_COLON_1_2; 256 state &= ~IN6PTON_DELIM; 257 } 258 if (d + 2 >= dbuf + sizeof(dbuf)) { 259 state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2); 260 } 261 cont: 262 if ((dc && d + 4 < dbuf + sizeof(dbuf)) || 263 d + 4 == dbuf + sizeof(dbuf)) { 264 state |= IN6PTON_DOT; 265 } 266 if (d >= dbuf + sizeof(dbuf)) { 267 state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK); 268 } 269 s++; 270 srclen--; 271 } 272 273 i = 15; d--; 274 275 if (dc) { 276 while(d >= dc) 277 dst[i--] = *d--; 278 while(i >= dc - dbuf) 279 dst[i--] = 0; 280 while(i >= 0) 281 dst[i--] = *d--; 282 } else 283 memcpy(dst, dbuf, sizeof(dbuf)); 284 285 ret = 1; 286 out: 287 if (end) 288 *end = s; 289 return ret; 290 } 291 292 EXPORT_SYMBOL(in6_pton); 293