libkern/net/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 #if defined(LIBC_SCCS) && !defined(lint)
  18 static const char rcsid[] = "$Id: inet_pton.c,v 1.3.18.2 2005/07/28 07:38:07 marka Exp $";
  19 #endif /* LIBC_SCCS and not lint */
  20
  21 #include <string.h>
  22
  23 #include <sys/param.h>
  24 #include <sys/socket.h>
  25 #include <sys/systm.h>
  26
  27 #include <netinet/in.h>
  28
  29 /*%
  30  * WARNING: Don't even consider trying to compile this on a system where
  31  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
  32  */
  33
  34 static int      inet_pton4(const char *src, u_char *dst);
  35 static int      inet_pton6(const char *src, u_char *dst);
  36
  37 /* int
  38  * inet_pton(af, src, dst)
  39  *      convert from presentation format (which usually means ASCII printable)
  40  *      to network format (which is usually some kind of binary format).
  41  * return:
  42  *      1 if the address was valid for the specified address family
  43  *      0 if the address wasn't valid (`dst' is untouched in this case)
  44  *      -1 if some other error occurred (`dst' is untouched in this case, too)
  45  * author:
  46  *      Paul Vixie, 1996.
  47  */
  48 int
  49 inet_pton(int af, const char *src, void *dst)
  50 {
  51         switch (af) {
  52         case AF_INET:
  53                 return (inet_pton4(src, dst));
  54         case AF_INET6:
  55                 return (inet_pton6(src, dst));
  56         default:
  57                 return (-1);
  58         }
  59         /* NOTREACHED */
  60 }
  61
  62 /* int
  63  * inet_pton4(src, dst)
  64  *      like inet_aton() but without all the hexadecimal and shorthand.
  65  * return:
  66  *      1 if `src' is a valid dotted quad, else 0.
  67  * notice:
  68  *      does not touch `dst' unless it's returning 1.
  69  * author:
  70  *      Paul Vixie, 1996.
  71  */
  72 static int
  73 inet_pton4(const char *src, u_char *dst)
  74 {
  75         static const char digits[] = "0123456789";
  76         int saw_digit, octets, ch;
  77 #define NS_INADDRSZ     4
  78         u_char tmp[NS_INADDRSZ], *tp;
  79
  80         saw_digit = 0;
  81         octets = 0;
  82         *(tp = tmp) = 0;
  83         while ((ch = *src++) != '\0') {
  84                 const char *pch;
  85
  86                 if ((pch = strchr(digits, ch)) != NULL) {
  87                         u_int new = *tp * 10 + (pch - digits);
  88
  89                         if (saw_digit && *tp == 0)
  90                                 return (0);
  91                         if (new > 255)
  92                                 return (0);
  93                         *tp = new;
  94                         if (!saw_digit) {
  95                                 if (++octets > 4)
  96                                         return (0);
  97                                 saw_digit = 1;
  98                         }
  99                 } else if (ch == '.' && saw_digit) {
 100                         if (octets == 4)
 101                                 return (0);
 102                         *++tp = 0;
 103                         saw_digit = 0;
 104                 } else
 105                         return (0);
 106         }
 107         if (octets < 4)
 108                 return (0);
 109         memcpy(dst, tmp, NS_INADDRSZ);
 110         return (1);
 111 }
 112
 113 /* int
 114  * inet_pton6(src, dst)
 115  *      convert presentation level address to network order binary form.
 116  * return:
 117  *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
 118  * notice:
 119  *      (1) does not touch `dst' unless it's returning 1.
 120  *      (2) :: in a full address is silently ignored.
 121  * credit:
 122  *      inspired by Mark Andrews.
 123  * author:
 124  *      Paul Vixie, 1996.
 125  */
 126 static int
 127 inet_pton6(const char *src, u_char *dst)
 128 {
 129         static const char xdigits_l[] = "0123456789abcdef",
 130                           xdigits_u[] = "0123456789ABCDEF";
 131 #define NS_IN6ADDRSZ    16
 132 #define NS_INT16SZ      2
 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 }