compat/inet_pton.c

   1 /*
   2  * Copyright (C) 1996-2001  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
   9  * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
  10  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
  11  * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
  13  * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
  14  * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
  15  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 #include <errno.h>
  19 #include <sys/types.h>
  20 #include <sys/socket.h>
  21 #include <netinet/in.h>
  22 #include <arpa/inet.h>
  23 #include <stdio.h>
  24 #include <string.h>
  25
  26 #ifndef NS_INT16SZ
  27 #define NS_INT16SZ       2
  28 #endif
  29
  30 #ifndef NS_INADDRSZ
  31 #define NS_INADDRSZ      4
  32 #endif
  33
  34 #ifndef NS_IN6ADDRSZ
  35 #define NS_IN6ADDRSZ    16
  36 #endif
  37
  38 /*
  39  * WARNING: Don't even consider trying to compile this on a system where
  40  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
  41  */
  42
  43 static int inet_pton4(const char *src, unsigned char *dst);
  44 static int inet_pton6(const char *src, unsigned char *dst);
  45
  46 /* int
  47  * inet_pton4(src, dst)
  48  *      like inet_aton() but without all the hexadecimal and shorthand.
  49  * return:
  50  *      1 if `src' is a valid dotted quad, else 0.
  51  * notice:
  52  *      does not touch `dst' unless it's returning 1.
  53  * author:
  54  *      Paul Vixie, 1996.
  55  */
  56 static int
  57 inet_pton4(const char *src, unsigned char *dst)
  58 {
  59         static const char digits[] = "0123456789";
  60         int saw_digit, octets, ch;
  61         unsigned char tmp[NS_INADDRSZ], *tp;
  62
  63         saw_digit = 0;
  64         octets = 0;
  65         *(tp = tmp) = 0;
  66         while ((ch = *src++) != '\0') {
  67                 const char *pch;
  68
  69                 if ((pch = strchr(digits, ch)) != NULL) {
  70                         unsigned int new = *tp * 10 + (pch - digits);
  71
  72                         if (new > 255)
  73                                 return (0);
  74                         *tp = new;
  75                         if (! saw_digit) {
  76                                 if (++octets > 4)
  77                                         return (0);
  78                                 saw_digit = 1;
  79                         }
  80                 } else if (ch == '.' && saw_digit) {
  81                         if (octets == 4)
  82                                 return (0);
  83                         *++tp = 0;
  84                         saw_digit = 0;
  85                 } else
  86                         return (0);
  87         }
  88         if (octets < 4)
  89                 return (0);
  90         memcpy(dst, tmp, NS_INADDRSZ);
  91         return (1);
  92 }
  93
  94 /* int
  95  * inet_pton6(src, dst)
  96  *      convert presentation level address to network order binary form.
  97  * return:
  98  *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
  99  * notice:
 100  *      (1) does not touch `dst' unless it's returning 1.
 101  *      (2) :: in a full address is silently ignored.
 102  * credit:
 103  *      inspired by Mark Andrews.
 104  * author:
 105  *      Paul Vixie, 1996.
 106  */
 107
 108 #ifndef NO_IPV6
 109 static int
 110 inet_pton6(const char *src, unsigned char *dst)
 111 {
 112         static const char xdigits_l[] = "0123456789abcdef",
 113                           xdigits_u[] = "0123456789ABCDEF";
 114         unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 115         const char *xdigits, *curtok;
 116         int ch, saw_xdigit;
 117         unsigned int val;
 118
 119         memset((tp = tmp), '\0', NS_IN6ADDRSZ);
 120         endp = tp + NS_IN6ADDRSZ;
 121         colonp = NULL;
 122         /* Leading :: requires some special handling. */
 123         if (*src == ':')
 124                 if (*++src != ':')
 125                         return (0);
 126         curtok = src;
 127         saw_xdigit = 0;
 128         val = 0;
 129         while ((ch = *src++) != '\0') {
 130                 const char *pch;
 131
 132                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
 133                         pch = strchr((xdigits = xdigits_u), ch);
 134                 if (pch != NULL) {
 135                         val <<= 4;
 136                         val |= (pch - xdigits);
 137                         if (val > 0xffff)
 138                                 return (0);
 139                         saw_xdigit = 1;
 140                         continue;
 141                 }
 142                 if (ch == ':') {
 143                         curtok = src;
 144                         if (!saw_xdigit) {
 145                                 if (colonp)
 146                                         return (0);
 147                                 colonp = tp;
 148                                 continue;
 149                         }
 150                         if (tp + NS_INT16SZ > endp)
 151                                 return (0);
 152                         *tp++ = (unsigned char) (val >> 8) & 0xff;
 153                         *tp++ = (unsigned char) val & 0xff;
 154                         saw_xdigit = 0;
 155                         val = 0;
 156                         continue;
 157                 }
 158                 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
 159                     inet_pton4(curtok, tp) > 0) {
 160                         tp += NS_INADDRSZ;
 161                         saw_xdigit = 0;
 162                         break;  /* '\0' was seen by inet_pton4(). */
 163                 }
 164                 return (0);
 165         }
 166         if (saw_xdigit) {
 167                 if (tp + NS_INT16SZ > endp)
 168                         return (0);
 169                 *tp++ = (unsigned char) (val >> 8) & 0xff;
 170                 *tp++ = (unsigned char) val & 0xff;
 171         }
 172         if (colonp != NULL) {
 173                 /*
 174                  * Since some memmove()'s erroneously fail to handle
 175                  * overlapping regions, we'll do the shift by hand.
 176                  */
 177                 const int n = tp - colonp;
 178                 int i;
 179
 180                 for (i = 1; i <= n; i++) {
 181                         endp[- i] = colonp[n - i];
 182                         colonp[n - i] = 0;
 183                 }
 184                 tp = endp;
 185         }
 186         if (tp != endp)
 187                 return (0);
 188         memcpy(dst, tmp, NS_IN6ADDRSZ);
 189         return (1);
 190 }
 191 #endif
 192
 193 /* int
 194  * isc_net_pton(af, src, dst)
 195  *      convert from presentation format (which usually means ASCII printable)
 196  *      to network format (which is usually some kind of binary format).
 197  * return:
 198  *      1 if the address was valid for the specified address family
 199  *      0 if the address wasn't valid (`dst' is untouched in this case)
 200  *      -1 if some other error occurred (`dst' is untouched in this case, too)
 201  * author:
 202  *      Paul Vixie, 1996.
 203  */
 204 int
 205 inet_pton(int af, const char *src, void *dst)
 206 {
 207         switch (af) {
 208         case AF_INET:
 209                 return (inet_pton4(src, dst));
 210 #ifndef NO_IPV6
 211         case AF_INET6:
 212                 return (inet_pton6(src, dst));
 213 #endif
 214         default:
 215                 errno = EAFNOSUPPORT;
 216                 return (-1);
 217         }
 218         /* NOTREACHED */
 219 }