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
  21 #include "../git-compat-util.h"
  22
  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 #ifndef NO_IPV6
  45 static int inet_pton6(const char *src, unsigned char *dst);
  46 #endif
  47
  48 /* int
  49  * inet_pton4(src, dst)
  50  *      like inet_aton() but without all the hexadecimal and shorthand.
  51  * return:
  52  *      1 if `src' is a valid dotted quad, else 0.
  53  * notice:
  54  *      does not touch `dst' unless it's returning 1.
  55  * author:
  56  *      Paul Vixie, 1996.
  57  */
  58 static int
  59 inet_pton4(const char *src, unsigned char *dst)
  60 {
  61         static const char digits[] = "0123456789";
  62         int saw_digit, octets, ch;
  63         unsigned char tmp[NS_INADDRSZ], *tp;
  64
  65         saw_digit = 0;
  66         octets = 0;
  67         *(tp = tmp) = 0;
  68         while ((ch = *src++) != '\0') {
  69                 const char *pch;
  70
  71                 if ((pch = strchr(digits, ch)) != NULL) {
  72                         unsigned int new = *tp * 10 + (pch - digits);
  73
  74                         if (new > 255)
  75                                 return (0);
  76                         *tp = new;
  77                         if (! saw_digit) {
  78                                 if (++octets > 4)
  79                                         return (0);
  80                                 saw_digit = 1;
  81                         }
  82                 } else if (ch == '.' && saw_digit) {
  83                         if (octets == 4)
  84                                 return (0);
  85                         *++tp = 0;
  86                         saw_digit = 0;
  87                 } else
  88                         return (0);
  89         }
  90         if (octets < 4)
  91                 return (0);
  92         memcpy(dst, tmp, NS_INADDRSZ);
  93         return (1);
  94 }
  95
  96 /* int
  97  * inet_pton6(src, dst)
  98  *      convert presentation level address to network order binary form.
  99  * return:
 100  *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
 101  * notice:
 102  *      (1) does not touch `dst' unless it's returning 1.
 103  *      (2) :: in a full address is silently ignored.
 104  * credit:
 105  *      inspired by Mark Andrews.
 106  * author:
 107  *      Paul Vixie, 1996.
 108  */
 109
 110 #ifndef NO_IPV6
 111 static int
 112 inet_pton6(const char *src, unsigned char *dst)
 113 {
 114         static const char xdigits_l[] = "0123456789abcdef",
 115                           xdigits_u[] = "0123456789ABCDEF";
 116         unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 117         const char *xdigits, *curtok;
 118         int ch, saw_xdigit;
 119         unsigned int val;
 120
 121         memset((tp = tmp), '\0', NS_IN6ADDRSZ);
 122         endp = tp + NS_IN6ADDRSZ;
 123         colonp = NULL;
 124         /* Leading :: requires some special handling. */
 125         if (*src == ':')
 126                 if (*++src != ':')
 127                         return (0);
 128         curtok = src;
 129         saw_xdigit = 0;
 130         val = 0;
 131         while ((ch = *src++) != '\0') {
 132                 const char *pch;
 133
 134                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
 135                         pch = strchr((xdigits = xdigits_u), ch);
 136                 if (pch != NULL) {
 137                         val <<= 4;
 138                         val |= (pch - xdigits);
 139                         if (val > 0xffff)
 140                                 return (0);
 141                         saw_xdigit = 1;
 142                         continue;
 143                 }
 144                 if (ch == ':') {
 145                         curtok = src;
 146                         if (!saw_xdigit) {
 147                                 if (colonp)
 148                                         return (0);
 149                                 colonp = tp;
 150                                 continue;
 151                         }
 152                         if (tp + NS_INT16SZ > endp)
 153                                 return (0);
 154                         *tp++ = (unsigned char) (val >> 8) & 0xff;
 155                         *tp++ = (unsigned char) val & 0xff;
 156                         saw_xdigit = 0;
 157                         val = 0;
 158                         continue;
 159                 }
 160                 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
 161                     inet_pton4(curtok, tp) > 0) {
 162                         tp += NS_INADDRSZ;
 163                         saw_xdigit = 0;
 164                         break;  /* '\0' was seen by inet_pton4(). */
 165                 }
 166                 return (0);
 167         }
 168         if (saw_xdigit) {
 169                 if (tp + NS_INT16SZ > endp)
 170                         return (0);
 171                 *tp++ = (unsigned char) (val >> 8) & 0xff;
 172                 *tp++ = (unsigned char) val & 0xff;
 173         }
 174         if (colonp != NULL) {
 175                 /*
 176                  * Since some memmove()'s erroneously fail to handle
 177                  * overlapping regions, we'll do the shift by hand.
 178                  */
 179                 const int n = tp - colonp;
 180                 int i;
 181
 182                 for (i = 1; i <= n; i++) {
 183                         endp[- i] = colonp[n - i];
 184                         colonp[n - i] = 0;
 185                 }
 186                 tp = endp;
 187         }
 188         if (tp != endp)
 189                 return (0);
 190         memcpy(dst, tmp, NS_IN6ADDRSZ);
 191         return (1);
 192 }
 193 #endif
 194
 195 /* int
 196  * isc_net_pton(af, src, dst)
 197  *      convert from presentation format (which usually means ASCII printable)
 198  *      to network format (which is usually some kind of binary format).
 199  * return:
 200  *      1 if the address was valid for the specified address family
 201  *      0 if the address wasn't valid (`dst' is untouched in this case)
 202  *      -1 if some other error occurred (`dst' is untouched in this case, too)
 203  * author:
 204  *      Paul Vixie, 1996.
 205  */
 206 int
 207 inet_pton(int af, const char *src, void *dst)
 208 {
 209         switch (af) {
 210         case AF_INET:
 211                 return (inet_pton4(src, dst));
 212 #ifndef NO_IPV6
 213         case AF_INET6:
 214                 return (inet_pton6(src, dst));
 215 #endif
 216         default:
 217                 errno = EAFNOSUPPORT;
 218                 return (-1);
 219         }
 220         /* NOTREACHED */
 221 }