lib/libc/inet/inet_pton.c

   1 /*
   2  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (c) 1996,1999 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 ISC DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  15  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  *
  17  * $Id: inet_pton.c,v 1.5 2005/07/28 06:51:47 marka Exp $
  18  */
  19
  20 #include "port_before.h"
  21 #include <sys/param.h>
  22 #include <sys/types.h>
  23 #include <sys/socket.h>
  24 #include <netinet/in.h>
  25 #include <arpa/inet.h>
  26 #include <arpa/nameser.h>
  27 #include <string.h>
  28 #include <errno.h>
  29 #include "port_after.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 * __restrict src, void * __restrict 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         memcpy(dst, tmp, NS_INADDRSZ);
 112         return (1);
 113 }
 114
 115 /* int
 116  * inet_pton6(src, dst)
 117  *      convert presentation level address to network order binary form.
 118  * return:
 119  *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
 120  * notice:
 121  *      (1) does not touch `dst' unless it's returning 1.
 122  *      (2) :: in a full address is silently ignored.
 123  * credit:
 124  *      inspired by Mark Andrews.
 125  * author:
 126  *      Paul Vixie, 1996.
 127  */
 128 static int
 129 inet_pton6(const char *src, u_char *dst)
 130 {
 131         static const char xdigits_l[] = "0123456789abcdef",
 132                           xdigits_u[] = "0123456789ABCDEF";
 133         u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 134         const char *xdigits, *curtok;
 135         int ch, seen_xdigits;
 136         u_int val;
 137
 138         memset((tp = tmp), '\0', NS_IN6ADDRSZ);
 139         endp = tp + NS_IN6ADDRSZ;
 140         colonp = NULL;
 141         /* Leading :: requires some special handling. */
 142         if (*src == ':')
 143                 if (*++src != ':')
 144                         return (0);
 145         curtok = src;
 146         seen_xdigits = 0;
 147         val = 0;
 148         while ((ch = *src++) != '\0') {
 149                 const char *pch;
 150
 151                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
 152                         pch = strchr((xdigits = xdigits_u), ch);
 153                 if (pch != NULL) {
 154                         val <<= 4;
 155                         val |= (pch - xdigits);
 156                         if (++seen_xdigits > 4)
 157                                 return (0);
 158                         continue;
 159                 }
 160                 if (ch == ':') {
 161                         curtok = src;
 162                         if (!seen_xdigits) {
 163                                 if (colonp)
 164                                         return (0);
 165                                 colonp = tp;
 166                                 continue;
 167                         } else if (*src == '\0') {
 168                                 return (0);
 169                         }
 170                         if (tp + NS_INT16SZ > endp)
 171                                 return (0);
 172                         *tp++ = (u_char) (val >> 8) & 0xff;
 173                         *tp++ = (u_char) val & 0xff;
 174                         seen_xdigits = 0;
 175                         val = 0;
 176                         continue;
 177                 }
 178                 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
 179                     inet_pton4(curtok, tp) > 0) {
 180                         tp += NS_INADDRSZ;
 181                         seen_xdigits = 0;
 182                         break;  /*%< '\\0' was seen by inet_pton4(). */
 183                 }
 184                 return (0);
 185         }
 186         if (seen_xdigits) {
 187                 if (tp + NS_INT16SZ > endp)
 188                         return (0);
 189                 *tp++ = (u_char) (val >> 8) & 0xff;
 190                 *tp++ = (u_char) val & 0xff;
 191         }
 192         if (colonp != NULL) {
 193                 /*
 194                  * Since some memmove()'s erroneously fail to handle
 195                  * overlapping regions, we'll do the shift by hand.
 196                  */
 197                 const int n = tp - colonp;
 198                 int i;
 199
 200                 if (tp == endp)
 201                         return (0);
 202                 for (i = 1; i <= n; i++) {
 203                         endp[- i] = colonp[n - i];
 204                         colonp[n - i] = 0;
 205                 }
 206                 tp = endp;
 207         }
 208         if (tp != endp)
 209                 return (0);
 210         memcpy(dst, tmp, NS_IN6ADDRSZ);
 211         return (1);
 212 }
 213
 214 /*
 215  * Weak aliases for applications that use certain private entry points,
 216  * and fail to include <arpa/inet.h>.
 217  */
 218 #undef inet_pton
 219 __weak_reference(__inet_pton, inet_pton);