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 "../git-compat-util.h"
  19
  20 #ifndef NS_INT16SZ
  21 #define NS_INT16SZ       2
  22 #endif
  23
  24 #ifndef NS_INADDRSZ
  25 #define NS_INADDRSZ      4
  26 #endif
  27
  28 #ifndef NS_IN6ADDRSZ
  29 #define NS_IN6ADDRSZ    16
  30 #endif
  31
  32 /*
  33  * WARNING: Don't even consider trying to compile this on a system where
  34  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
  35  */
  36
  37 static int inet_pton4(const char *src, unsigned char *dst);
  38 #ifndef NO_IPV6
  39 static int inet_pton6(const char *src, unsigned char *dst);
  40 #endif
  41
  42 /* int
  43  * inet_pton4(src, dst)
  44  *      like inet_aton() but without all the hexadecimal and shorthand.
  45  * return:
  46  *      1 if `src' is a valid dotted quad, else 0.
  47  * notice:
  48  *      does not touch `dst' unless it's returning 1.
  49  * author:
  50  *      Paul Vixie, 1996.
  51  */
  52 static int
  53 inet_pton4(const char *src, unsigned char *dst)
  54 {
  55         static const char digits[] = "0123456789";
  56         int saw_digit, octets, ch;
  57         unsigned char tmp[NS_INADDRSZ], *tp;
  58
  59         saw_digit = 0;
  60         octets = 0;
  61         *(tp = tmp) = 0;
  62         while ((ch = *src++) != '\0') {
  63                 const char *pch;
  64
  65                 if ((pch = strchr(digits, ch)) != NULL) {
  66                         unsigned int new = *tp * 10 + (pch - digits);
  67
  68                         if (new > 255)
  69                                 return (0);
  70                         *tp = new;
  71                         if (! saw_digit) {
  72                                 if (++octets > 4)
  73                                         return (0);
  74                                 saw_digit = 1;
  75                         }
  76                 } else if (ch == '.' && saw_digit) {
  77                         if (octets == 4)
  78                                 return (0);
  79                         *++tp = 0;
  80                         saw_digit = 0;
  81                 } else
  82                         return (0);
  83         }
  84         if (octets < 4)
  85                 return (0);
  86         memcpy(dst, tmp, NS_INADDRSZ);
  87         return (1);
  88 }
  89
  90 /* int
  91  * inet_pton6(src, dst)
  92  *      convert presentation level address to network order binary form.
  93  * return:
  94  *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
  95  * notice:
  96  *      (1) does not touch `dst' unless it's returning 1.
  97  *      (2) :: in a full address is silently ignored.
  98  * credit:
  99  *      inspired by Mark Andrews.
 100  * author:
 101  *      Paul Vixie, 1996.
 102  */
 103
 104 #ifndef NO_IPV6
 105 static int
 106 inet_pton6(const char *src, unsigned char *dst)
 107 {
 108         static const char xdigits_l[] = "0123456789abcdef",
 109                           xdigits_u[] = "0123456789ABCDEF";
 110         unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 111         const char *xdigits, *curtok;
 112         int ch, saw_xdigit;
 113         unsigned int val;
 114
 115         memset((tp = tmp), '\0', NS_IN6ADDRSZ);
 116         endp = tp + NS_IN6ADDRSZ;
 117         colonp = NULL;
 118         /* Leading :: requires some special handling. */
 119         if (*src == ':')
 120                 if (*++src != ':')
 121                         return (0);
 122         curtok = src;
 123         saw_xdigit = 0;
 124         val = 0;
 125         while ((ch = *src++) != '\0') {
 126                 const char *pch;
 127
 128                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
 129                         pch = strchr((xdigits = xdigits_u), ch);
 130                 if (pch != NULL) {
 131                         val <<= 4;
 132                         val |= (pch - xdigits);
 133                         if (val > 0xffff)
 134                                 return (0);
 135                         saw_xdigit = 1;
 136                         continue;
 137                 }
 138                 if (ch == ':') {
 139                         curtok = src;
 140                         if (!saw_xdigit) {
 141                                 if (colonp)
 142                                         return (0);
 143                                 colonp = tp;
 144                                 continue;
 145                         }
 146                         if (tp + NS_INT16SZ > endp)
 147                                 return (0);
 148                         *tp++ = (unsigned char) (val >> 8) & 0xff;
 149                         *tp++ = (unsigned char) val & 0xff;
 150                         saw_xdigit = 0;
 151                         val = 0;
 152                         continue;
 153                 }
 154                 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
 155                     inet_pton4(curtok, tp) > 0) {
 156                         tp += NS_INADDRSZ;
 157                         saw_xdigit = 0;
 158                         break;  /* '\0' was seen by inet_pton4(). */
 159                 }
 160                 return (0);
 161         }
 162         if (saw_xdigit) {
 163                 if (tp + NS_INT16SZ > endp)
 164                         return (0);
 165                 *tp++ = (unsigned char) (val >> 8) & 0xff;
 166                 *tp++ = (unsigned char) val & 0xff;
 167         }
 168         if (colonp != NULL) {
 169                 /*
 170                  * Since some memmove()'s erroneously fail to handle
 171                  * overlapping regions, we'll do the shift by hand.
 172                  */
 173                 const int n = tp - colonp;
 174                 int i;
 175
 176                 for (i = 1; i <= n; i++) {
 177                         endp[- i] = colonp[n - i];
 178                         colonp[n - i] = 0;
 179                 }
 180                 tp = endp;
 181         }
 182         if (tp != endp)
 183                 return (0);
 184         memcpy(dst, tmp, NS_IN6ADDRSZ);
 185         return (1);
 186 }
 187 #endif
 188
 189 /* int
 190  * isc_net_pton(af, src, dst)
 191  *      convert from presentation format (which usually means ASCII printable)
 192  *      to network format (which is usually some kind of binary format).
 193  * return:
 194  *      1 if the address was valid for the specified address family
 195  *      0 if the address wasn't valid (`dst' is untouched in this case)
 196  *      -1 if some other error occurred (`dst' is untouched in this case, too)
 197  * author:
 198  *      Paul Vixie, 1996.
 199  */
 200 int
 201 inet_pton(int af, const char *src, void *dst)
 202 {
 203         switch (af) {
 204         case AF_INET:
 205                 return (inet_pton4(src, dst));
 206 #ifndef NO_IPV6
 207         case AF_INET6:
 208                 return (inet_pton6(src, dst));
 209 #endif
 210         default:
 211                 errno = EAFNOSUPPORT;
 212                 return (-1);
 213         }
 214         /* NOTREACHED */
 215 }