1 /* $OpenBSD: inet_pton.c,v 1.8 2010/05/06 15:47:14 claudio Exp $ */ 2 3 /* Copyright (c) 1996 by Internet Software Consortium. 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS 10 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES 11 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE 12 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 13 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 14 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 15 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 16 * SOFTWARE. 17 */ 18 19 #include <sys/param.h> 20 #include <sys/types.h> 21 #include <sys/socket.h> 22 #include <netinet/in.h> 23 #include <arpa/inet.h> 24 #include <arpa/nameser.h> 25 #include <string.h> 26 #include <errno.h> 27 28 /* 29 * WARNING: Don't even consider trying to compile this on a system where 30 * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX. 31 */ 32 33 static int inet_pton4(const char *src, u_char *dst); 34 static int inet_pton6(const char *src, u_char *dst); 35 36 /* int 37 * inet_pton(af, src, dst) 38 * convert from presentation format (which usually means ASCII printable) 39 * to network format (which is usually some kind of binary format). 40 * return: 41 * 1 if the address was valid for the specified address family 42 * 0 if the address wasn't valid (`dst' is untouched in this case) 43 * -1 if some other error occurred (`dst' is untouched in this case, too) 44 * author: 45 * Paul Vixie, 1996. 46 */ 47 int 48 inet_pton(int af, const char *src, void *dst) 49 { 50 switch (af) { 51 case AF_INET: 52 return (inet_pton4(src, dst)); 53 case AF_INET6: 54 return (inet_pton6(src, dst)); 55 default: 56 errno = EAFNOSUPPORT; 57 return (-1); 58 } 59 /* NOTREACHED */ 60 } 61 62 /* int 63 * inet_pton4(src, dst) 64 * like inet_aton() but without all the hexadecimal and shorthand. 65 * return: 66 * 1 if `src' is a valid dotted quad, else 0. 67 * notice: 68 * does not touch `dst' unless it's returning 1. 69 * author: 70 * Paul Vixie, 1996. 71 */ 72 static int 73 inet_pton4(const char *src, u_char *dst) 74 { 75 static const char digits[] = "0123456789"; 76 int saw_digit, octets, ch; 77 u_char tmp[INADDRSZ], *tp; 78 79 saw_digit = 0; 80 octets = 0; 81 *(tp = tmp) = 0; 82 while ((ch = *src++) != '\0') { 83 const char *pch; 84 85 if ((pch = strchr(digits, ch)) != NULL) { 86 u_int new = *tp * 10 + (pch - digits); 87 88 if (new > 255) 89 return (0); 90 if (! saw_digit) { 91 if (++octets > 4) 92 return (0); 93 saw_digit = 1; 94 } 95 *tp = new; 96 } else if (ch == '.' && saw_digit) { 97 if (octets == 4) 98 return (0); 99 *++tp = 0; 100 saw_digit = 0; 101 } else 102 return (0); 103 } 104 if (octets < 4) 105 return (0); 106 107 memcpy(dst, tmp, INADDRSZ); 108 return (1); 109 } 110 111 /* int 112 * inet_pton6(src, dst) 113 * convert presentation level address to network order binary form. 114 * return: 115 * 1 if `src' is a valid [RFC1884 2.2] address, else 0. 116 * notice: 117 * does not touch `dst' unless it's returning 1. 118 * credit: 119 * inspired by Mark Andrews. 120 * author: 121 * Paul Vixie, 1996. 122 */ 123 static int 124 inet_pton6(const char *src, u_char *dst) 125 { 126 static const char xdigits_l[] = "0123456789abcdef", 127 xdigits_u[] = "0123456789ABCDEF"; 128 u_char tmp[IN6ADDRSZ], *tp, *endp, *colonp; 129 const char *xdigits, *curtok; 130 int ch, saw_xdigit, count_xdigit; 131 u_int val; 132 133 memset((tp = tmp), '\0', IN6ADDRSZ); 134 endp = tp + IN6ADDRSZ; 135 colonp = NULL; 136 /* Leading :: requires some special handling. */ 137 if (*src == ':') 138 if (*++src != ':') 139 return (0); 140 curtok = src; 141 saw_xdigit = count_xdigit = 0; 142 val = 0; 143 while ((ch = *src++) != '\0') { 144 const char *pch; 145 146 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL) 147 pch = strchr((xdigits = xdigits_u), ch); 148 if (pch != NULL) { 149 if (count_xdigit >= 4) 150 return (0); 151 val <<= 4; 152 val |= (pch - xdigits); 153 if (val > 0xffff) 154 return (0); 155 saw_xdigit = 1; 156 count_xdigit++; 157 continue; 158 } 159 if (ch == ':') { 160 curtok = src; 161 if (!saw_xdigit) { 162 if (colonp) 163 return (0); 164 colonp = tp; 165 continue; 166 } else if (*src == '\0') { 167 return (0); 168 } 169 if (tp + INT16SZ > endp) 170 return (0); 171 *tp++ = (u_char) (val >> 8) & 0xff; 172 *tp++ = (u_char) val & 0xff; 173 saw_xdigit = 0; 174 count_xdigit = 0; 175 val = 0; 176 continue; 177 } 178 if (ch == '.' && ((tp + INADDRSZ) <= endp) && 179 inet_pton4(curtok, tp) > 0) { 180 tp += INADDRSZ; 181 saw_xdigit = 0; 182 count_xdigit = 0; 183 break; /* '\0' was seen by inet_pton4(). */ 184 } 185 return (0); 186 } 187 if (saw_xdigit) { 188 if (tp + INT16SZ > endp) 189 return (0); 190 *tp++ = (u_char) (val >> 8) & 0xff; 191 *tp++ = (u_char) val & 0xff; 192 } 193 if (colonp != NULL) { 194 /* 195 * Since some memmove()'s erroneously fail to handle 196 * overlapping regions, we'll do the shift by hand. 197 */ 198 const int n = tp - colonp; 199 int i; 200 201 if (tp == endp) 202 return (0); 203 for (i = 1; i <= n; i++) { 204 endp[- i] = colonp[n - i]; 205 colonp[n - i] = 0; 206 } 207 tp = endp; 208 } 209 if (tp != endp) 210 return (0); 211 memcpy(dst, tmp, IN6ADDRSZ); 212 return (1); 213 } 214