1 /*- 2 * SPDX-License-Identifier: ISC 3 * 4 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 5 * Copyright (c) 1998,1999 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 ISC DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 17 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #if defined(LIBC_SCCS) && !defined(lint) 21 static const char rcsid[] = "$Id: inet_cidr_pton.c,v 1.6 2005/04/27 04:56:19 sra Exp $"; 22 #endif 23 #include <sys/cdefs.h> 24 __FBSDID("$FreeBSD$"); 25 26 #include "port_before.h" 27 28 #include <sys/types.h> 29 #include <sys/socket.h> 30 #include <netinet/in.h> 31 #include <arpa/nameser.h> 32 #include <arpa/inet.h> 33 34 #include <assert.h> 35 #include <ctype.h> 36 #include <errno.h> 37 #include <stdio.h> 38 #include <string.h> 39 #include <stdlib.h> 40 41 #include "port_after.h" 42 43 #ifdef SPRINTF_CHAR 44 # define SPRINTF(x) strlen(sprintf/**/x) 45 #else 46 # define SPRINTF(x) ((size_t)sprintf x) 47 #endif 48 49 static int inet_cidr_pton_ipv4 (const char *src, u_char *dst, int *bits, 50 int ipv6); 51 static int inet_cidr_pton_ipv6 (const char *src, u_char *dst, int *bits); 52 53 static int getbits(const char *, int ipv6); 54 55 /*% 56 * int 57 * inet_cidr_pton(af, src, dst, *bits) 58 * convert network address from presentation to network format. 59 * accepts inet_pton()'s input for this "af" plus trailing "/CIDR". 60 * "dst" is assumed large enough for its "af". "bits" is set to the 61 * /CIDR prefix length, which can have defaults (like /32 for IPv4). 62 * return: 63 * -1 if an error occurred (inspect errno; ENOENT means bad format). 64 * 0 if successful conversion occurred. 65 * note: 66 * 192.5.5.1/28 has a nonzero host part, which means it isn't a network 67 * as called for by inet_net_pton() but it can be a host address with 68 * an included netmask. 69 * author: 70 * Paul Vixie (ISC), October 1998 71 */ 72 int 73 inet_cidr_pton(int af, const char *src, void *dst, int *bits) { 74 switch (af) { 75 case AF_INET: 76 return (inet_cidr_pton_ipv4(src, dst, bits, 0)); 77 case AF_INET6: 78 return (inet_cidr_pton_ipv6(src, dst, bits)); 79 default: 80 errno = EAFNOSUPPORT; 81 return (-1); 82 } 83 } 84 85 static const char digits[] = "0123456789"; 86 87 static int 88 inet_cidr_pton_ipv4(const char *src, u_char *dst, int *pbits, int ipv6) { 89 const u_char *odst = dst; 90 int n, ch, tmp, bits; 91 size_t size = 4; 92 93 /* Get the mantissa. */ 94 while (ch = *src++, (isascii(ch) && isdigit(ch))) { 95 tmp = 0; 96 do { 97 n = strchr(digits, ch) - digits; 98 assert(n >= 0 && n <= 9); 99 tmp *= 10; 100 tmp += n; 101 if (tmp > 255) 102 goto enoent; 103 } while ((ch = *src++) != '\0' && isascii(ch) && isdigit(ch)); 104 if (size-- == 0U) 105 goto emsgsize; 106 *dst++ = (u_char) tmp; 107 if (ch == '\0' || ch == '/') 108 break; 109 if (ch != '.') 110 goto enoent; 111 } 112 113 /* Get the prefix length if any. */ 114 bits = -1; 115 if (ch == '/' && dst > odst) { 116 bits = getbits(src, ipv6); 117 if (bits == -2) 118 goto enoent; 119 } else if (ch != '\0') 120 goto enoent; 121 122 /* Prefix length can default to /32 only if all four octets spec'd. */ 123 if (bits == -1) { 124 if (dst - odst == 4) 125 bits = ipv6 ? 128 : 32; 126 else 127 goto enoent; 128 } 129 130 /* If nothing was written to the destination, we found no address. */ 131 if (dst == odst) 132 goto enoent; 133 134 /* If prefix length overspecifies mantissa, life is bad. */ 135 if (((bits - (ipv6 ? 96 : 0)) / 8) > (dst - odst)) 136 goto enoent; 137 138 /* Extend address to four octets. */ 139 while (size-- > 0U) 140 *dst++ = 0; 141 142 *pbits = bits; 143 return (0); 144 145 enoent: 146 errno = ENOENT; 147 return (-1); 148 149 emsgsize: 150 errno = EMSGSIZE; 151 return (-1); 152 } 153 154 static int 155 inet_cidr_pton_ipv6(const char *src, u_char *dst, int *pbits) { 156 static const char xdigits_l[] = "0123456789abcdef", 157 xdigits_u[] = "0123456789ABCDEF"; 158 u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp; 159 const char *xdigits, *curtok; 160 int ch, saw_xdigit; 161 u_int val; 162 int bits; 163 164 memset((tp = tmp), '\0', NS_IN6ADDRSZ); 165 endp = tp + NS_IN6ADDRSZ; 166 colonp = NULL; 167 /* Leading :: requires some special handling. */ 168 if (*src == ':') 169 if (*++src != ':') 170 return (0); 171 curtok = src; 172 saw_xdigit = 0; 173 val = 0; 174 bits = -1; 175 while ((ch = *src++) != '\0') { 176 const char *pch; 177 178 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL) 179 pch = strchr((xdigits = xdigits_u), ch); 180 if (pch != NULL) { 181 val <<= 4; 182 val |= (pch - xdigits); 183 if (val > 0xffff) 184 return (0); 185 saw_xdigit = 1; 186 continue; 187 } 188 if (ch == ':') { 189 curtok = src; 190 if (!saw_xdigit) { 191 if (colonp) 192 return (0); 193 colonp = tp; 194 continue; 195 } else if (*src == '\0') { 196 return (0); 197 } 198 if (tp + NS_INT16SZ > endp) 199 return (0); 200 *tp++ = (u_char) (val >> 8) & 0xff; 201 *tp++ = (u_char) val & 0xff; 202 saw_xdigit = 0; 203 val = 0; 204 continue; 205 } 206 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) && 207 inet_cidr_pton_ipv4(curtok, tp, &bits, 1) == 0) { 208 tp += NS_INADDRSZ; 209 saw_xdigit = 0; 210 break; /*%< '\\0' was seen by inet_pton4(). */ 211 } 212 if (ch == '/') { 213 bits = getbits(src, 1); 214 if (bits == -2) 215 goto enoent; 216 break; 217 } 218 goto enoent; 219 } 220 if (saw_xdigit) { 221 if (tp + NS_INT16SZ > endp) 222 goto emsgsize; 223 *tp++ = (u_char) (val >> 8) & 0xff; 224 *tp++ = (u_char) val & 0xff; 225 } 226 if (colonp != NULL) { 227 /* 228 * Since some memmove()'s erroneously fail to handle 229 * overlapping regions, we'll do the shift by hand. 230 */ 231 const int n = tp - colonp; 232 int i; 233 234 if (tp == endp) 235 goto enoent; 236 for (i = 1; i <= n; i++) { 237 endp[- i] = colonp[n - i]; 238 colonp[n - i] = 0; 239 } 240 tp = endp; 241 } 242 243 memcpy(dst, tmp, NS_IN6ADDRSZ); 244 245 *pbits = bits; 246 return (0); 247 248 enoent: 249 errno = ENOENT; 250 return (-1); 251 252 emsgsize: 253 errno = EMSGSIZE; 254 return (-1); 255 } 256 257 static int 258 getbits(const char *src, int ipv6) { 259 int bits = 0; 260 char *cp, ch; 261 262 if (*src == '\0') /*%< syntax */ 263 return (-2); 264 do { 265 ch = *src++; 266 cp = strchr(digits, ch); 267 if (cp == NULL) /*%< syntax */ 268 return (-2); 269 bits *= 10; 270 bits += cp - digits; 271 if (bits == 0 && *src != '\0') /*%< no leading zeros */ 272 return (-2); 273 if (bits > (ipv6 ? 128 : 32)) /*%< range error */ 274 return (-2); 275 } while (*src != '\0'); 276 277 return (bits); 278 } 279 280 /*! \file */ 281