net/FreeBSD/inet_net_pton.c

   1 /*
   2  * Copyright (c) 1996 by Internet Software Consortium.
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
   9  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  10  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  11  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  12  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  13  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  14  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  15  * SOFTWARE.
  16  */
  17
  18 #if defined(LIBC_SCCS) && !defined(lint)
  19 static const char orig_rcsid[] = "From Id: inet_net_pton.c,v 1.8 1996/11/21 10:28:12 vixie Exp $";
  20 #endif
  21 #include <sys/cdefs.h>
  22 __FBSDID("$FreeBSD: src/lib/libc/net/inet_net_pton.c,v 1.8 2002/03/22 21:52:29 obrien Exp $");
  23
  24 #include <sys/types.h>
  25 #include <sys/socket.h>
  26 #include <netinet/in.h>
  27 #include <arpa/inet.h>
  28
  29 #include <assert.h>
  30 #include <ctype.h>
  31 #include <errno.h>
  32 #include <stdio.h>
  33 #include <string.h>
  34 #include <stdlib.h>
  35
  36 #ifdef SPRINTF_CHAR
  37 # define SPRINTF(x) strlen(sprintf/**/x)
  38 #else
  39 # define SPRINTF(x) ((size_t)sprintf x)
  40 #endif
  41
  42 static int      inet_net_pton_ipv4(const char *src, u_char *dst, size_t size);
  43
  44 /*
  45  * static int
  46  * inet_net_pton(af, src, dst, size)
  47  *      convert network number from presentation to network format.
  48  *      accepts hex octets, hex strings, decimal octets, and /CIDR.
  49  *      "size" is in bytes and describes "dst".
  50  * return:
  51  *      number of bits, either imputed classfully or specified with /CIDR,
  52  *      or -1 if some failure occurred (check errno).  ENOENT means it was
  53  *      not a valid network specification.
  54  * author:
  55  *      Paul Vixie (ISC), June 1996
  56  */
  57 int
  58 inet_net_pton(af, src, dst, size)
  59         int af;
  60         const char *src;
  61         void *dst;
  62         size_t size;
  63 {
  64         switch (af) {
  65         case AF_INET:
  66                 return (inet_net_pton_ipv4(src, dst, size));
  67         default:
  68                 errno = EAFNOSUPPORT;
  69                 return (-1);
  70         }
  71 }
  72
  73 /*
  74  * static int
  75  * inet_net_pton_ipv4(src, dst, size)
  76  *      convert IPv4 network number from presentation to network format.
  77  *      accepts hex octets, hex strings, decimal octets, and /CIDR.
  78  *      "size" is in bytes and describes "dst".
  79  * return:
  80  *      number of bits, either imputed classfully or specified with /CIDR,
  81  *      or -1 if some failure occurred (check errno).  ENOENT means it was
  82  *      not an IPv4 network specification.
  83  * note:
  84  *      network byte order assumed.  this means 192.5.5.240/28 has
  85  *      0x11110000 in its fourth octet.
  86  * author:
  87  *      Paul Vixie (ISC), June 1996
  88  */
  89 static int
  90 inet_net_pton_ipv4(src, dst, size)
  91         const char *src;
  92         u_char *dst;
  93         size_t size;
  94 {
  95         static const char
  96                 xdigits[] = "0123456789abcdef",
  97                 digits[] = "0123456789";
  98         int n, ch, tmp, dirty, bits;
  99         const u_char *odst = dst;
 100
 101         ch = *src++;
 102         if (ch == '0' && (src[0] == 'x' || src[0] == 'X')
 103             && isascii(src[1]) && isxdigit(src[1])) {
 104                 /* Hexadecimal: Eat nybble string. */
 105                 if (size <= 0)
 106                         goto emsgsize;
 107                 *dst = 0, dirty = 0;
 108                 src++;  /* skip x or X. */
 109                 while ((ch = *src++) != '\0' &&
 110                        isascii(ch) && isxdigit(ch)) {
 111                         if (isupper(ch))
 112                                 ch = tolower(ch);
 113                         n = strchr(xdigits, ch) - xdigits;
 114                         assert(n >= 0 && n <= 15);
 115                         *dst |= n;
 116                         if (!dirty++)
 117                                 *dst <<= 4;
 118                         else if (size-- > 0)
 119                                 *++dst = 0, dirty = 0;
 120                         else
 121                                 goto emsgsize;
 122                 }
 123                 if (dirty)
 124                         size--;
 125         } else if (isascii(ch) && isdigit(ch)) {
 126                 /* Decimal: eat dotted digit string. */
 127                 for (;;) {
 128                         tmp = 0;
 129                         do {
 130                                 n = strchr(digits, ch) - digits;
 131                                 assert(n >= 0 && n <= 9);
 132                                 tmp *= 10;
 133                                 tmp += n;
 134                                 if (tmp > 255)
 135                                         goto enoent;
 136                         } while ((ch = *src++) != '\0' &&
 137                                  isascii(ch) && isdigit(ch));
 138                         if (size-- <= 0)
 139                                 goto emsgsize;
 140                         *dst++ = (u_char) tmp;
 141                         if (ch == '\0' || ch == '/')
 142                                 break;
 143                         if (ch != '.')
 144                                 goto enoent;
 145                         ch = *src++;
 146                         if (!isascii(ch) || !isdigit(ch))
 147                                 goto enoent;
 148                 }
 149         } else
 150                 goto enoent;
 151
 152         bits = -1;
 153         if (ch == '/' && isascii(src[0]) && isdigit(src[0]) && dst > odst) {
 154                 /* CIDR width specifier.  Nothing can follow it. */
 155                 ch = *src++;    /* Skip over the /. */
 156                 bits = 0;
 157                 do {
 158                         n = strchr(digits, ch) - digits;
 159                         assert(n >= 0 && n <= 9);
 160                         bits *= 10;
 161                         bits += n;
 162                 } while ((ch = *src++) != '\0' && isascii(ch) && isdigit(ch));
 163                 if (ch != '\0')
 164                         goto enoent;
 165                 if (bits > 32)
 166                         goto emsgsize;
 167         }
 168
 169         /* Firey death and destruction unless we prefetched EOS. */
 170         if (ch != '\0')
 171                 goto enoent;
 172
 173         /* If nothing was written to the destination, we found no address. */
 174         if (dst == odst)
 175                 goto enoent;
 176         /* If no CIDR spec was given, infer width from net class. */
 177         if (bits == -1) {
 178                 if (*odst >= 240)       /* Class E */
 179                         bits = 32;
 180                 else if (*odst >= 224)  /* Class D */
 181                         bits = 4;
 182                 else if (*odst >= 192)  /* Class C */
 183                         bits = 24;
 184                 else if (*odst >= 128)  /* Class B */
 185                         bits = 16;
 186                 else                    /* Class A */
 187                         bits = 8;
 188                 /* If imputed mask is narrower than specified octets, widen. */
 189                 if (bits >= 8 && bits < ((dst - odst) * 8))
 190                         bits = (dst - odst) * 8;
 191         }
 192         /* Extend network to cover the actual mask. */
 193         while (bits > ((dst - odst) * 8)) {
 194                 if (size-- <= 0)
 195                         goto emsgsize;
 196                 *dst++ = '\0';
 197         }
 198         return (bits);
 199
 200  enoent:
 201         errno = ENOENT;
 202         return (-1);
 203
 204  emsgsize:
 205         errno = EMSGSIZE;
 206         return (-1);
 207 }
 208
 209 /*
 210  * Weak aliases for applications that use certain private entry points,
 211  * and fail to include <arpa/inet.h>.
 212  */
 213 #undef inet_net_pton
 214 __weak_reference(__inet_net_pton, inet_net_pton);