1 /* $OpenBSD: inet_net_pton.c,v 1.8 2013/11/25 18:23:51 deraadt 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 = (unsigned char)*src++; 89 if (ch == '0' && (src[0] == 'x' || src[0] == 'X') 90 && isascii((unsigned char)src[1]) && isxdigit((unsigned char)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 = (unsigned char)*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 = (unsigned char)*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 = (unsigned char)*src++; 133 if (!isascii(ch) || !isdigit(ch)) 134 goto enoent; 135 } 136 } else 137 goto enoent; 138 139 bits = -1; 140 if (ch == '/' && isascii((unsigned char)src[0]) && 141 isdigit((unsigned char)src[0]) && dst > odst) { 142 /* CIDR width specifier. Nothing can follow it. */ 143 ch = (unsigned char)*src++; /* Skip over the /. */ 144 bits = 0; 145 do { 146 n = strchr(digits, ch) - digits; 147 assert(n >= 0 && n <= 9); 148 bits *= 10; 149 bits += n; 150 if (bits > 32) 151 goto emsgsize; 152 } while ((ch = (unsigned char)*src++) != '\0' && 153 isascii(ch) && isdigit(ch)); 154 if (ch != '\0') 155 goto enoent; 156 } 157 158 /* Firey death and destruction unless we prefetched EOS. */ 159 if (ch != '\0') 160 goto enoent; 161 162 /* If nothing was written to the destination, we found no address. */ 163 if (dst == odst) 164 goto enoent; 165 /* If no CIDR spec was given, infer width from net class. */ 166 if (bits == -1) { 167 if (*odst >= 240) /* Class E */ 168 bits = 32; 169 else if (*odst >= 224) /* Class D */ 170 bits = 4; 171 else if (*odst >= 192) /* Class C */ 172 bits = 24; 173 else if (*odst >= 128) /* Class B */ 174 bits = 16; 175 else /* Class A */ 176 bits = 8; 177 /* If imputed mask is narrower than specified octets, widen. */ 178 if (bits < ((dst - odst) * 8)) 179 bits = (dst - odst) * 8; 180 } 181 /* Extend network to cover the actual mask. */ 182 while (bits > ((dst - odst) * 8)) { 183 if (size-- <= 0) 184 goto emsgsize; 185 *dst++ = '\0'; 186 } 187 return (bits); 188 189 enoent: 190 errno = ENOENT; 191 return (-1); 192 193 emsgsize: 194 errno = EMSGSIZE; 195 return (-1); 196 } 197 198 199 static int 200 inet_net_pton_ipv6(const char *src, u_char *dst, size_t size) 201 { 202 int ret; 203 int bits; 204 char buf[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255:255:255:255/128")]; 205 char *sep; 206 const char *errstr; 207 208 if (strlcpy(buf, src, sizeof buf) >= sizeof buf) { 209 errno = EMSGSIZE; 210 return (-1); 211 } 212 213 sep = strchr(buf, '/'); 214 if (sep != NULL) 215 *sep++ = '\0'; 216 217 ret = inet_pton(AF_INET6, buf, dst); 218 if (ret != 1) 219 return (-1); 220 221 if (sep == NULL) 222 return 128; 223 224 bits = strtonum(sep, 0, 128, &errstr); 225 if (errstr) { 226 errno = EINVAL; 227 return (-1); 228 } 229 230 return bits; 231 } 232