lib/libc/net/inet_pton.c

   1 /*      $KAME: inet_pton.c,v 1.5 2001/08/20 02:32:40 itojun Exp $       */
   2
   3 /* Copyright (c) 1996 by Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
  10  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  11  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  12  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  13  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  14  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  15  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  16  * SOFTWARE.
  17  *
  18  * $FreeBSD: src/lib/libc/net/inet_pton.c,v 1.6.2.1 2002/04/28 05:40:24 suz Exp $
  19  * $DragonFly: src/lib/libc/net/inet_pton.c,v 1.5 2007/04/19 12:52:29 corecode Exp $
  20  */
  21
  22 #include <sys/param.h>
  23 #include <sys/types.h>
  24 #include <sys/socket.h>
  25 #include <netinet/in.h>
  26 #include <arpa/inet.h>
  27 #include <arpa/nameser.h>
  28 #include <string.h>
  29 #include <errno.h>
  30
  31 /*
  32  * WARNING: Don't even consider trying to compile this on a system where
  33  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
  34  */
  35
  36 static int      inet_pton4 (const char *src, u_char *dst);
  37 static int      inet_pton6 (const char *src, u_char *dst);
  38
  39 /* int
  40  * inet_pton(af, src, dst)
  41  *      convert from presentation format (which usually means ASCII printable)
  42  *      to network format (which is usually some kind of binary format).
  43  * return:
  44  *      1 if the address was valid for the specified address family
  45  *      0 if the address wasn't valid (`dst' is untouched in this case)
  46  *      -1 if some other error occurred (`dst' is untouched in this case, too)
  47  * author:
  48  *      Paul Vixie, 1996.
  49  */
  50 int
  51 inet_pton(int af, const char *src, void *dst)
  52 {
  53         switch (af) {
  54         case AF_INET:
  55                 return (inet_pton4(src, dst));
  56         case AF_INET6:
  57                 return (inet_pton6(src, dst));
  58         default:
  59                 errno = EAFNOSUPPORT;
  60                 return (-1);
  61         }
  62         /* NOTREACHED */
  63 }
  64
  65 /* int
  66  * inet_pton4(src, dst)
  67  *      like inet_aton() but without all the hexadecimal and shorthand.
  68  * return:
  69  *      1 if `src' is a valid dotted quad, else 0.
  70  * notice:
  71  *      does not touch `dst' unless it's returning 1.
  72  * author:
  73  *      Paul Vixie, 1996.
  74  */
  75 static int
  76 inet_pton4(const char *src, u_char *dst)
  77 {
  78         static const char digits[] = "0123456789";
  79         int saw_digit, octets, ch;
  80         u_char tmp[NS_INADDRSZ], *tp;
  81
  82         saw_digit = 0;
  83         octets = 0;
  84         *(tp = tmp) = 0;
  85         while ((ch = *src++) != '\0') {
  86                 const char *pch;
  87
  88                 if ((pch = strchr(digits, ch)) != NULL) {
  89                         u_int new = *tp * 10 + (pch - digits);
  90
  91                         if (saw_digit && *tp == 0)
  92                                 return (0);
  93                         if (new > 255)
  94                                 return (0);
  95                         *tp = new;
  96                         if (! saw_digit) {
  97                                 if (++octets > 4)
  98                                         return (0);
  99                                 saw_digit = 1;
 100                         }
 101                 } else if (ch == '.' && saw_digit) {
 102                         if (octets == 4)
 103                                 return (0);
 104                         *++tp = 0;
 105                         saw_digit = 0;
 106                 } else
 107                         return (0);
 108         }
 109         if (octets < 4)
 110                 return (0);
 111
 112         memcpy(dst, tmp, NS_INADDRSZ);
 113         return (1);
 114 }
 115
 116 /* int
 117  * inet_pton6(src, dst)
 118  *      convert presentation level address to network order binary form.
 119  * return:
 120  *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
 121  * notice:
 122  *      (1) does not touch `dst' unless it's returning 1.
 123  *      (2) :: in a full address is silently ignored.
 124  * credit:
 125  *      inspired by Mark Andrews.
 126  * author:
 127  *      Paul Vixie, 1996.
 128  */
 129 static int
 130 inet_pton6(const char *src, u_char *dst)
 131 {
 132         static const char xdigits_l[] = "0123456789abcdef",
 133                           xdigits_u[] = "0123456789ABCDEF";
 134         u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 135         const char *xdigits, *curtok;
 136         int ch, saw_xdigit;
 137         u_int val;
 138
 139         memset((tp = tmp), '\0', NS_IN6ADDRSZ);
 140         endp = tp + NS_IN6ADDRSZ;
 141         colonp = NULL;
 142         /* Leading :: requires some special handling. */
 143         if (*src == ':')
 144                 if (*++src != ':')
 145                         return (0);
 146         curtok = src;
 147         saw_xdigit = 0;
 148         val = 0;
 149         while ((ch = *src++) != '\0') {
 150                 const char *pch;
 151
 152                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
 153                         pch = strchr((xdigits = xdigits_u), ch);
 154                 if (pch != NULL) {
 155                         val <<= 4;
 156                         val |= (pch - xdigits);
 157                         if (val > 0xffff)
 158                                 return (0);
 159                         saw_xdigit = 1;
 160                         continue;
 161                 }
 162                 if (ch == ':') {
 163                         curtok = src;
 164                         if (!saw_xdigit) {
 165                                 if (colonp)
 166                                         return (0);
 167                                 colonp = tp;
 168                                 continue;
 169                         } else if (*src == '\0')
 170                                 return (0);
 171                         if (tp + NS_INT16SZ > endp)
 172                                 return (0);
 173                         *tp++ = (u_char) (val >> 8) & 0xff;
 174                         *tp++ = (u_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++ = (u_char) (val >> 8) & 0xff;
 191                 *tp++ = (u_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 }
 214
 215 /*
 216  * Weak aliases for applications that use certain private entry points,
 217  * and fail to include <arpa/inet.h>.
 218  */
 219 #undef inet_pton
 220 __weak_reference(__inet_pton, inet_pton);