1 /* $OpenBSD: inet_net_pton.c,v 1.7 2012/06/22 19:13:37 gilles Exp $ */ 2 3 /* 4 * Copyright (c) 2012 by Gilles Chehade <gilles@openbsd.org> 5 * Copyright (c) 1996 by Internet Software Consortium. 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS 12 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES 13 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE 14 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 15 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 16 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 17 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 18 * SOFTWARE. 19 */ 20 21 #include <sys/types.h> 22 #include <sys/socket.h> 23 #include <netinet/in.h> 24 #include <arpa/inet.h> 25 26 #include <assert.h> 27 #include <ctype.h> 28 #include <errno.h> 29 #include <stdio.h> 30 #include <string.h> 31 #include <stdlib.h> 32 33 static int inet_net_pton_ipv4(const char *, u_char *, size_t); 34 static int inet_net_pton_ipv6(const char *, u_char *, size_t); 35 36 /* 37 * static int 38 * inet_net_pton(af, src, dst, size) 39 * convert network number from presentation to network format. 40 * accepts hex octets, hex strings, decimal octets, and /CIDR. 41 * "size" is in bytes and describes "dst". 42 * return: 43 * number of bits, either imputed classfully or specified with /CIDR, 44 * or -1 if some failure occurred (check errno). ENOENT means it was 45 * not a valid network specification. 46 * author: 47 * Paul Vixie (ISC), June 1996 48 */ 49 int 50 inet_net_pton(int af, const char *src, void *dst, size_t size) 51 { 52 switch (af) { 53 case AF_INET: 54 return (inet_net_pton_ipv4(src, dst, size)); 55 case AF_INET6: 56 return (inet_net_pton_ipv6(src, dst, size)); 57 default: 58 errno = EAFNOSUPPORT; 59 return (-1); 60 } 61 } 62 63 /* 64 * static int 65 * inet_net_pton_ipv4(src, dst, size) 66 * convert IPv4 network number from presentation to network format. 67 * accepts hex octets, hex strings, decimal octets, and /CIDR. 68 * "size" is in bytes and describes "dst". 69 * return: 70 * number of bits, either imputed classfully or specified with /CIDR, 71 * or -1 if some failure occurred (check errno). ENOENT means it was 72 * not an IPv4 network specification. 73 * note: 74 * network byte order assumed. this means 192.5.5.240/28 has 75 * 0x11110000 in its fourth octet. 76 * author: 77 * Paul Vixie (ISC), June 1996 78 */ 79 static int 80 inet_net_pton_ipv4(const char *src, u_char *dst, size_t size) 81 { 82 static const char 83 xdigits[] = "0123456789abcdef", 84 digits[] = "0123456789"; 85 int n, ch, tmp, dirty, bits; 86 const u_char *odst = dst; 87 88 ch = *src++; 89 if (ch == '0' && (src[0] == 'x' || src[0] == 'X') 90 && isascii(src[1]) && isxdigit(src[1])) { 91 /* Hexadecimal: Eat nybble string. */ 92 if (size <= 0) 93 goto emsgsize; 94 *dst = 0, dirty = 0; 95 src++; /* skip x or X. */ 96 while ((ch = *src++) != '\0' && 97 isascii(ch) && isxdigit(ch)) { 98 if (isupper(ch)) 99 ch = tolower(ch); 100 n = strchr(xdigits, ch) - xdigits; 101 assert(n >= 0 && n <= 15); 102 *dst |= n; 103 if (!dirty++) 104 *dst <<= 4; 105 else if (size-- > 0) 106 *++dst = 0, dirty = 0; 107 else 108 goto emsgsize; 109 } 110 if (dirty) 111 size--; 112 } else if (isascii(ch) && isdigit(ch)) { 113 /* Decimal: eat dotted digit string. */ 114 for (;;) { 115 tmp = 0; 116 do { 117 n = strchr(digits, ch) - digits; 118 assert(n >= 0 && n <= 9); 119 tmp *= 10; 120 tmp += n; 121 if (tmp > 255) 122 goto enoent; 123 } while ((ch = *src++) != '\0' && 124 isascii(ch) && isdigit(ch)); 125 if (size-- <= 0) 126 goto emsgsize; 127 *dst++ = (u_char) tmp; 128 if (ch == '\0' || ch == '/') 129 break; 130 if (ch != '.') 131 goto enoent; 132 ch = *src++; 133 if (!isascii(ch) || !isdigit(ch)) 134 goto enoent; 135 } 136 } else 137 goto enoent; 138 139 bits = -1; 140 if (ch == '/' && isascii(src[0]) && isdigit(src[0]) && dst > odst) { 141 /* CIDR width specifier. Nothing can follow it. */ 142 ch = *src++; /* Skip over the /. */ 143 bits = 0; 144 do { 145 n = strchr(digits, ch) - digits; 146 assert(n >= 0 && n <= 9); 147 bits *= 10; 148 bits += n; 149 if (bits > 32) 150 goto emsgsize; 151 } while ((ch = *src++) != '\0' && 152 isascii(ch) && isdigit(ch)); 153 if (ch != '\0') 154 goto enoent; 155 } 156 157 /* Firey death and destruction unless we prefetched EOS. */ 158 if (ch != '\0') 159 goto enoent; 160 161 /* If nothing was written to the destination, we found no address. */ 162 if (dst == odst) 163 goto enoent; 164 /* If no CIDR spec was given, infer width from net class. */ 165 if (bits == -1) { 166 if (*odst >= 240) /* Class E */ 167 bits = 32; 168 else if (*odst >= 224) /* Class D */ 169 bits = 4; 170 else if (*odst >= 192) /* Class C */ 171 bits = 24; 172 else if (*odst >= 128) /* Class B */ 173 bits = 16; 174 else /* Class A */ 175 bits = 8; 176 /* If imputed mask is narrower than specified octets, widen. */ 177 if (bits < ((dst - odst) * 8)) 178 bits = (dst - odst) * 8; 179 } 180 /* Extend network to cover the actual mask. */ 181 while (bits > ((dst - odst) * 8)) { 182 if (size-- <= 0) 183 goto emsgsize; 184 *dst++ = '\0'; 185 } 186 return (bits); 187 188 enoent: 189 errno = ENOENT; 190 return (-1); 191 192 emsgsize: 193 errno = EMSGSIZE; 194 return (-1); 195 } 196 197 198 static int 199 inet_net_pton_ipv6(const char *src, u_char *dst, size_t size) 200 { 201 int ret; 202 int bits; 203 char buf[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255:255:255:255/128")]; 204 char *sep; 205 const char *errstr; 206 207 if (strlcpy(buf, src, sizeof buf) >= sizeof buf) { 208 errno = EMSGSIZE; 209 return (-1); 210 } 211 212 sep = strchr(buf, '/'); 213 if (sep != NULL) 214 *sep++ = '\0'; 215 216 ret = inet_pton(AF_INET6, buf, dst); 217 if (ret != 1) 218 return (-1); 219 220 if (sep == NULL) 221 return 128; 222 223 bits = strtonum(sep, 0, 128, &errstr); 224 if (errstr) { 225 errno = EINVAL; 226 return (-1); 227 } 228 229 return bits; 230 } 231