dist/ntp/libisc/inet_pton.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (C) 1996-2003  Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  17  * PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 #if defined(LIBC_SCCS) && !defined(lint)
  21 static char rcsid[] =
  22         "Id: inet_pton.c,v 1.10.2.4.2.1 2004/03/06 08:14:31 marka Exp";
  23 #endif /* LIBC_SCCS and not lint */
  24
  25 #include <config.h>
  26
  27 #include <errno.h>
  28 #include <string.h>
  29
  30 #include <isc/net.h>
  31
  32 #define NS_INT16SZ       2
  33 #define NS_INADDRSZ      4
  34 #define NS_IN6ADDRSZ    16
  35
  36 /*
  37  * WARNING: Don't even consider trying to compile this on a system where
  38  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
  39  */
  40
  41 static int inet_pton4(const char *src, unsigned char *dst);
  42 static int inet_pton6(const char *src, unsigned char *dst);
  43
  44 /* int
  45  * isc_net_pton(af, src, dst)
  46  *      convert from presentation format (which usually means ASCII printable)
  47  *      to network format (which is usually some kind of binary format).
  48  * return:
  49  *      1 if the address was valid for the specified address family
  50  *      0 if the address wasn't valid (`dst' is untouched in this case)
  51  *      -1 if some other error occurred (`dst' is untouched in this case, too)
  52  * author:
  53  *      Paul Vixie, 1996.
  54  */
  55 int
  56 isc_net_pton(int af, const char *src, void *dst) {
  57         switch (af) {
  58         case AF_INET:
  59                 return (inet_pton4(src, dst));
  60         case AF_INET6:
  61                 return (inet_pton6(src, dst));
  62         default:
  63                 errno = EAFNOSUPPORT;
  64                 return (-1);
  65         }
  66         /* NOTREACHED */
  67 }
  68
  69 /* int
  70  * inet_pton4(src, dst)
  71  *      like inet_aton() but without all the hexadecimal and shorthand.
  72  * return:
  73  *      1 if `src' is a valid dotted quad, else 0.
  74  * notice:
  75  *      does not touch `dst' unless it's returning 1.
  76  * author:
  77  *      Paul Vixie, 1996.
  78  */
  79 static int
  80 inet_pton4(const char *src, unsigned char *dst) {
  81         static const char digits[] = "0123456789";
  82         int saw_digit, octets, ch;
  83         unsigned char tmp[NS_INADDRSZ], *tp;
  84
  85         saw_digit = 0;
  86         octets = 0;
  87         *(tp = tmp) = 0;
  88         while ((ch = *src++) != '\0') {
  89                 const char *pch;
  90
  91                 if ((pch = strchr(digits, ch)) != NULL) {
  92                         unsigned int new = *tp * 10 + (pch - digits);
  93
  94                         if (saw_digit && *tp == 0)
  95                                 return (0);
  96                         if (new > 255)
  97                                 return (0);
  98                         *tp = (unsigned char) new;
  99                         if (!saw_digit) {
 100                                 if (++octets > 4)
 101                                         return (0);
 102                                 saw_digit = 1;
 103                         }
 104                 } else if (ch == '.' && saw_digit) {
 105                         if (octets == 4)
 106                                 return (0);
 107                         *++tp = 0;
 108                         saw_digit = 0;
 109                 } else
 110                         return (0);
 111         }
 112         if (octets < 4)
 113                 return (0);
 114         memcpy(dst, tmp, NS_INADDRSZ);
 115         return (1);
 116 }
 117
 118 /* int
 119  * inet_pton6(src, dst)
 120  *      convert presentation level address to network order binary form.
 121  * return:
 122  *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
 123  * notice:
 124  *      (1) does not touch `dst' unless it's returning 1.
 125  *      (2) :: in a full address is silently ignored.
 126  * credit:
 127  *      inspired by Mark Andrews.
 128  * author:
 129  *      Paul Vixie, 1996.
 130  */
 131 static int
 132 inet_pton6(const char *src, unsigned char *dst) {
 133         static const char xdigits_l[] = "0123456789abcdef",
 134                           xdigits_u[] = "0123456789ABCDEF";
 135         unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 136         const char *xdigits, *curtok;
 137         int ch, saw_xdigit;
 138         unsigned int val;
 139
 140         memset((tp = tmp), '\0', NS_IN6ADDRSZ);
 141         endp = tp + NS_IN6ADDRSZ;
 142         colonp = NULL;
 143         /* Leading :: requires some special handling. */
 144         if (*src == ':')
 145                 if (*++src != ':')
 146                         return (0);
 147         curtok = src;
 148         saw_xdigit = 0;
 149         val = 0;
 150         while ((ch = *src++) != '\0') {
 151                 const char *pch;
 152
 153                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
 154                         pch = strchr((xdigits = xdigits_u), ch);
 155                 if (pch != NULL) {
 156                         val <<= 4;
 157                         val |= (pch - xdigits);
 158                         if (val > 0xffff)
 159                                 return (0);
 160                         saw_xdigit = 1;
 161                         continue;
 162                 }
 163                 if (ch == ':') {
 164                         curtok = src;
 165                         if (!saw_xdigit) {
 166                                 if (colonp)
 167                                         return (0);
 168                                 colonp = tp;
 169                                 continue;
 170                         }
 171                         if (tp + NS_INT16SZ > endp)
 172                                 return (0);
 173                         *tp++ = (unsigned char) ((val >> 8) & 0xff);
 174                         *tp++ = (unsigned char) (val & 0xff);
 175                         saw_xdigit = 0;
 176                         val = 0;
 177                         continue;
 178                 }
 179                 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
 180                     inet_pton4(curtok, tp) > 0) {
 181                         tp += NS_INADDRSZ;
 182                         saw_xdigit = 0;
 183                         break;  /* '\0' was seen by inet_pton4(). */
 184                 }
 185                 return (0);
 186         }
 187         if (saw_xdigit) {
 188                 if (tp + NS_INT16SZ > endp)
 189                         return (0);
 190                 *tp++ = (unsigned char) ((val >> 8) & 0xff);
 191                 *tp++ = (unsigned char) (val & 0xff);
 192         }
 193         if (colonp != NULL) {
 194                 /*
 195                  * Since some memmove()'s erroneously fail to handle
 196                  * overlapping regions, we'll do the shift by hand.
 197                  */
 198                 const int n = tp - colonp;
 199                 int i;
 200
 201                 if (tp == endp)
 202                         return (0);
 203                 for (i = 1; i <= n; i++) {
 204                         endp[- i] = colonp[n - i];
 205                         colonp[n - i] = 0;
 206                 }
 207                 tp = endp;
 208         }
 209         if (tp != endp)
 210                 return (0);
 211         memcpy(dst, tmp, NS_IN6ADDRSZ);
 212         return (1);
 213 }