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 <sys/socket.h>
  22 #include <netinet/in.h>
  23 #include <arpa/inet.h>
  24 #include <stdio.h>
  25 #include <string.h>
  26
  27 #ifndef NS_INT16SZ
  28 #define NS_INT16SZ       2
  29 #endif
  30
  31 #ifndef NS_INADDRSZ
  32 #define NS_INADDRSZ      4
  33 #endif
  34
  35 #ifndef NS_IN6ADDRSZ
  36 #define NS_IN6ADDRSZ    16
  37 #endif
  38
  39 /*
  40  * WARNING: Don't even consider trying to compile this on a system where
  41  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
  42  */
  43
  44 static int inet_pton4(const char *src, unsigned char *dst);
  45 static int inet_pton6(const char *src, unsigned char *dst);
  46
  47 /* int
  48  * inet_pton4(src, dst)
  49  *      like inet_aton() but without all the hexadecimal and shorthand.
  50  * return:
  51  *      1 if `src' is a valid dotted quad, else 0.
  52  * notice:
  53  *      does not touch `dst' unless it's returning 1.
  54  * author:
  55  *      Paul Vixie, 1996.
  56  */
  57 static int
  58 inet_pton4(const char *src, unsigned char *dst)
  59 {
  60         static const char digits[] = "0123456789";
  61         int saw_digit, octets, ch;
  62         unsigned char tmp[NS_INADDRSZ], *tp;
  63
  64         saw_digit = 0;
  65         octets = 0;
  66         *(tp = tmp) = 0;
  67         while ((ch = *src++) != '\0') {
  68                 const char *pch;
  69
  70                 if ((pch = strchr(digits, ch)) != NULL) {
  71                         unsigned int new = *tp * 10 + (pch - digits);
  72
  73                         if (new > 255)
  74                                 return (0);
  75                         *tp = new;
  76                         if (! saw_digit) {
  77                                 if (++octets > 4)
  78                                         return (0);
  79                                 saw_digit = 1;
  80                         }
  81                 } else if (ch == '.' && saw_digit) {
  82                         if (octets == 4)
  83                                 return (0);
  84                         *++tp = 0;
  85                         saw_digit = 0;
  86                 } else
  87                         return (0);
  88         }
  89         if (octets < 4)
  90                 return (0);
  91         memcpy(dst, tmp, NS_INADDRSZ);
  92         return (1);
  93 }
  94
  95 /* int
  96  * inet_pton6(src, dst)
  97  *      convert presentation level address to network order binary form.
  98  * return:
  99  *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
 100  * notice:
 101  *      (1) does not touch `dst' unless it's returning 1.
 102  *      (2) :: in a full address is silently ignored.
 103  * credit:
 104  *      inspired by Mark Andrews.
 105  * author:
 106  *      Paul Vixie, 1996.
 107  */
 108
 109 #ifndef NO_IPV6
 110 static int
 111 inet_pton6(const char *src, unsigned char *dst)
 112 {
 113         static const char xdigits_l[] = "0123456789abcdef",
 114                           xdigits_u[] = "0123456789ABCDEF";
 115         unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 116         const char *xdigits, *curtok;
 117         int ch, saw_xdigit;
 118         unsigned int val;
 119
 120         memset((tp = tmp), '\0', NS_IN6ADDRSZ);
 121         endp = tp + NS_IN6ADDRSZ;
 122         colonp = NULL;
 123         /* Leading :: requires some special handling. */
 124         if (*src == ':')
 125                 if (*++src != ':')
 126                         return (0);
 127         curtok = src;
 128         saw_xdigit = 0;
 129         val = 0;
 130         while ((ch = *src++) != '\0') {
 131                 const char *pch;
 132
 133                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
 134                         pch = strchr((xdigits = xdigits_u), ch);
 135                 if (pch != NULL) {
 136                         val <<= 4;
 137                         val |= (pch - xdigits);
 138                         if (val > 0xffff)
 139                                 return (0);
 140                         saw_xdigit = 1;
 141                         continue;
 142                 }
 143                 if (ch == ':') {
 144                         curtok = src;
 145                         if (!saw_xdigit) {
 146                                 if (colonp)
 147                                         return (0);
 148                                 colonp = tp;
 149                                 continue;
 150                         }
 151                         if (tp + NS_INT16SZ > endp)
 152                                 return (0);
 153                         *tp++ = (unsigned char) (val >> 8) & 0xff;
 154                         *tp++ = (unsigned char) val & 0xff;
 155                         saw_xdigit = 0;
 156                         val = 0;
 157                         continue;
 158                 }
 159                 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
 160                     inet_pton4(curtok, tp) > 0) {
 161                         tp += NS_INADDRSZ;
 162                         saw_xdigit = 0;
 163                         break;  /* '\0' was seen by inet_pton4(). */
 164                 }
 165                 return (0);
 166         }
 167         if (saw_xdigit) {
 168                 if (tp + NS_INT16SZ > endp)
 169                         return (0);
 170                 *tp++ = (unsigned char) (val >> 8) & 0xff;
 171                 *tp++ = (unsigned char) val & 0xff;
 172         }
 173         if (colonp != NULL) {
 174                 /*
 175                  * Since some memmove()'s erroneously fail to handle
 176                  * overlapping regions, we'll do the shift by hand.
 177                  */
 178                 const int n = tp - colonp;
 179                 int i;
 180
 181                 for (i = 1; i <= n; i++) {
 182                         endp[- i] = colonp[n - i];
 183                         colonp[n - i] = 0;
 184                 }
 185                 tp = endp;
 186         }
 187         if (tp != endp)
 188                 return (0);
 189         memcpy(dst, tmp, NS_IN6ADDRSZ);
 190         return (1);
 191 }
 192 #endif
 193
 194 /* int
 195  * isc_net_pton(af, src, dst)
 196  *      convert from presentation format (which usually means ASCII printable)
 197  *      to network format (which is usually some kind of binary format).
 198  * return:
 199  *      1 if the address was valid for the specified address family
 200  *      0 if the address wasn't valid (`dst' is untouched in this case)
 201  *      -1 if some other error occurred (`dst' is untouched in this case, too)
 202  * author:
 203  *      Paul Vixie, 1996.
 204  */
 205 int
 206 inet_pton(int af, const char *src, void *dst)
 207 {
 208         switch (af) {
 209         case AF_INET:
 210                 return (inet_pton4(src, dst));
 211 #ifndef NO_IPV6
 212         case AF_INET6:
 213                 return (inet_pton6(src, dst));
 214 #endif
 215         default:
 216                 errno = EAFNOSUPPORT;
 217                 return (-1);
 218         }
 219         /* NOTREACHED */
 220 }