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 + (u_int)(pch - digits);
  88
  89                         if (saw_digit && *tp == 0) {
  90                                 return 0;
  91                         }
  92                         if (new > 255) {
  93                                 return 0;
  94                         }
  95                         *tp = (u_char)new;
  96                         if (!saw_digit) {
  97                                 if (++octets > 4) {
  98                                         return 0;
  99                                 }
 100                                 saw_digit = 1;
 101                         }
 102                 } else if (ch == '.' && saw_digit) {
 103                         if (octets == 4) {
 104                                 return 0;
 105                         }
 106                         *++tp = 0;
 107                         saw_digit = 0;
 108                 } else {
 109                         return 0;
 110                 }
 111         }
 112         if (octets < 4) {
 113                 return 0;
 114         }
 115         memcpy(dst, tmp, NS_INADDRSZ);
 116         return 1;
 117 }
 118
 119 /* int
 120  * inet_pton6(src, dst)
 121  *      convert presentation level address to network order binary form.
 122  * return:
 123  *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
 124  * notice:
 125  *      (1) does not touch `dst' unless it's returning 1.
 126  *      (2) :: in a full address is silently ignored.
 127  * credit:
 128  *      inspired by Mark Andrews.
 129  * author:
 130  *      Paul Vixie, 1996.
 131  */
 132 static int
 133 inet_pton6(const char *src, u_char *dst)
 134 {
 135         static const char xdigits_l[] = "0123456789abcdef",
 136             xdigits_u[] = "0123456789ABCDEF";
 137 #define NS_IN6ADDRSZ    16
 138 #define NS_INT16SZ      2
 139         u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 140         const char *xdigits, *curtok;
 141         int ch, seen_xdigits;
 142         u_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                 }
 152         }
 153         curtok = src;
 154         seen_xdigits = 0;
 155         val = 0;
 156         while ((ch = *src++) != '\0') {
 157                 const char *pch;
 158
 159                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL) {
 160                         pch = strchr((xdigits = xdigits_u), ch);
 161                 }
 162                 if (pch != NULL) {
 163                         val <<= 4;
 164                         val |= (pch - xdigits);
 165                         if (++seen_xdigits > 4) {
 166                                 return 0;
 167                         }
 168                         continue;
 169                 }
 170                 if (ch == ':') {
 171                         curtok = src;
 172                         if (!seen_xdigits) {
 173                                 if (colonp) {
 174                                         return 0;
 175                                 }
 176                                 colonp = tp;
 177                                 continue;
 178                         } else if (*src == '\0') {
 179                                 return 0;
 180                         }
 181                         if (tp + NS_INT16SZ > endp) {
 182                                 return 0;
 183                         }
 184                         *tp++ = (u_char) (val >> 8) & 0xff;
 185                         *tp++ = (u_char) val & 0xff;
 186                         seen_xdigits = 0;
 187                         val = 0;
 188                         continue;
 189                 }
 190                 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
 191                     inet_pton4(curtok, tp) > 0) {
 192                         tp += NS_INADDRSZ;
 193                         seen_xdigits = 0;
 194                         break;  /*%< '\\0' was seen by inet_pton4(). */
 195                 }
 196                 return 0;
 197         }
 198         if (seen_xdigits) {
 199                 if (tp + NS_INT16SZ > endp) {
 200                         return 0;
 201                 }
 202                 *tp++ = (u_char) (val >> 8) & 0xff;
 203                 *tp++ = (u_char) val & 0xff;
 204         }
 205         if (colonp != NULL) {
 206                 /*
 207                  * Since some memmove()'s erroneously fail to handle
 208                  * overlapping regions, we'll do the shift by hand.
 209                  */
 210                 const long n = tp - colonp;
 211                 int i;
 212
 213                 if (tp == endp) {
 214                         return 0;
 215                 }
 216                 for (i = 1; i <= n; i++) {
 217                         endp[-i] = colonp[n - i];
 218                         colonp[n - i] = 0;
 219                 }
 220                 tp = endp;
 221         }
 222         if (tp != endp) {
 223                 return 0;
 224         }
 225         memcpy(dst, tmp, NS_IN6ADDRSZ);
 226         return 1;
 227 }