external/bsd/ntp/dist/lib/isc/inet_pton.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (C) 1996-2003  Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and/or 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 /*! \file */
  21
  22 #if defined(LIBC_SCCS) && !defined(lint)
  23 static char rcsid[] =
  24         "Id: inet_pton.c,v 1.19 2007/06/19 23:47:17 tbox Exp";
  25 #endif /* LIBC_SCCS and not lint */
  26
  27 #include <config.h>
  28
  29 #include <errno.h>
  30 #include <string.h>
  31
  32 #include <isc/net.h>
  33
  34 /*% INT16 Size */
  35 #define NS_INT16SZ       2
  36 /*% IPv4 Address Size */
  37 #define NS_INADDRSZ      4
  38 /*% IPv6 Address Size */
  39 #define NS_IN6ADDRSZ    16
  40
  41 /*
  42  * WARNING: Don't even consider trying to compile this on a system where
  43  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
  44  */
  45
  46 static int inet_pton4(const char *src, unsigned char *dst);
  47 static int inet_pton6(const char *src, unsigned char *dst);
  48
  49 /*%
  50  *      convert from presentation format (which usually means ASCII printable)
  51  *      to network format (which is usually some kind of binary format).
  52  * \return
  53  *      1 if the address was valid for the specified address family
  54  *      0 if the address wasn't valid (`dst' is untouched in this case)
  55  *      -1 if some other error occurred (`dst' is untouched in this case, too)
  56  * \author
  57  *      Paul Vixie, 1996.
  58  */
  59 int
  60 isc_net_pton(int af, const char *src, void *dst) {
  61         switch (af) {
  62         case AF_INET:
  63                 return (inet_pton4(src, dst));
  64         case AF_INET6:
  65                 return (inet_pton6(src, dst));
  66         default:
  67                 errno = EAFNOSUPPORT;
  68                 return (-1);
  69         }
  70         /* NOTREACHED */
  71 }
  72
  73 /*!\fn static int inet_pton4(const char *src, unsigned char *dst)
  74  * \brief
  75  *      like inet_aton() but without all the hexadecimal and shorthand.
  76  * \return
  77  *      1 if `src' is a valid dotted quad, else 0.
  78  * \note
  79  *      does not touch `dst' unless it's returning 1.
  80  * \author
  81  *      Paul Vixie, 1996.
  82  */
  83 static int
  84 inet_pton4(const char *src, unsigned char *dst) {
  85         static const char digits[] = "0123456789";
  86         int saw_digit, octets, ch;
  87         unsigned char tmp[NS_INADDRSZ], *tp;
  88
  89         saw_digit = 0;
  90         octets = 0;
  91         *(tp = tmp) = 0;
  92         while ((ch = *src++) != '\0') {
  93                 const char *pch;
  94
  95                 if ((pch = strchr(digits, ch)) != NULL) {
  96                         unsigned int new = *tp * 10 + (pch - digits);
  97
  98                         if (saw_digit && *tp == 0)
  99                                 return (0);
 100                         if (new > 255)
 101                                 return (0);
 102                         *tp = new;
 103                         if (!saw_digit) {
 104                                 if (++octets > 4)
 105                                         return (0);
 106                                 saw_digit = 1;
 107                         }
 108                 } else if (ch == '.' && saw_digit) {
 109                         if (octets == 4)
 110                                 return (0);
 111                         *++tp = 0;
 112                         saw_digit = 0;
 113                 } else
 114                         return (0);
 115         }
 116         if (octets < 4)
 117                 return (0);
 118         memcpy(dst, tmp, NS_INADDRSZ);
 119         return (1);
 120 }
 121
 122 /*%
 123  *      convert presentation level address to network order binary form.
 124  * \return
 125  *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
 126  * \note
 127  *      (1) does not touch `dst' unless it's returning 1.
 128  * \note
 129  *      (2) :: in a full address is silently ignored.
 130  * \author
 131  *      inspired by Mark Andrews.
 132  * \author
 133  *      Paul Vixie, 1996.
 134  */
 135 static int
 136 inet_pton6(const char *src, unsigned char *dst) {
 137         static const char xdigits_l[] = "0123456789abcdef",
 138                           xdigits_u[] = "0123456789ABCDEF";
 139         unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 140         const char *xdigits, *curtok;
 141         int ch, seen_xdigits;
 142         unsigned int val;
 143
 144         memset((tp = tmp), '\0', NS_IN6ADDRSZ);
 145         endp = tp + NS_IN6ADDRSZ;
 146         colonp = NULL;
 147         /* Leading :: requires some special handling. */
 148         if (*src == ':')
 149                 if (*++src != ':')
 150                         return (0);
 151         curtok = src;
 152         seen_xdigits = 0;
 153         val = 0;
 154         while ((ch = *src++) != '\0') {
 155                 const char *pch;
 156
 157                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
 158                         pch = strchr((xdigits = xdigits_u), ch);
 159                 if (pch != NULL) {
 160                         val <<= 4;
 161                         val |= (pch - xdigits);
 162                         if (++seen_xdigits > 4)
 163                                 return (0);
 164                         continue;
 165                 }
 166                 if (ch == ':') {
 167                         curtok = src;
 168                         if (!seen_xdigits) {
 169                                 if (colonp)
 170                                         return (0);
 171                                 colonp = tp;
 172                                 continue;
 173                         }
 174                         if (tp + NS_INT16SZ > endp)
 175                                 return (0);
 176                         *tp++ = (unsigned char) (val >> 8) & 0xff;
 177                         *tp++ = (unsigned char) val & 0xff;
 178                         seen_xdigits = 0;
 179                         val = 0;
 180                         continue;
 181                 }
 182                 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
 183                     inet_pton4(curtok, tp) > 0) {
 184                         tp += NS_INADDRSZ;
 185                         seen_xdigits = 0;
 186                         break;  /* '\0' was seen by inet_pton4(). */
 187                 }
 188                 return (0);
 189         }
 190         if (seen_xdigits) {
 191                 if (tp + NS_INT16SZ > endp)
 192                         return (0);
 193                 *tp++ = (unsigned char) (val >> 8) & 0xff;
 194                 *tp++ = (unsigned char) val & 0xff;
 195         }
 196         if (colonp != NULL) {
 197                 /*
 198                  * Since some memmove()'s erroneously fail to handle
 199                  * overlapping regions, we'll do the shift by hand.
 200                  */
 201                 const int n = tp - colonp;
 202                 int i;
 203
 204                 if (tp == endp)
 205                         return (0);
 206                 for (i = 1; i <= n; i++) {
 207                         endp[- i] = colonp[n - i];
 208                         colonp[n - i] = 0;
 209                 }
 210                 tp = endp;
 211         }
 212         if (tp != endp)
 213                 return (0);
 214         memcpy(dst, tmp, NS_IN6ADDRSZ);
 215         return (1);
 216 }