lib/libc/net/linkaddr.c

   1 /*      $NetBSD: linkaddr.c,v 1.14 2005/11/29 03:11:59 christos Exp $   */
   2
   3 /*-
   4  * Copyright (c) 1990, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 #if 0
  35 static char sccsid[] = "@(#)linkaddr.c  8.1 (Berkeley) 6/4/93";
  36 #else
  37 __RCSID("$NetBSD: linkaddr.c,v 1.14 2005/11/29 03:11:59 christos Exp $");
  38 #endif
  39 #endif /* LIBC_SCCS and not lint */
  40
  41 #include <sys/types.h>
  42 #include <sys/socket.h>
  43 #include <net/if_dl.h>
  44
  45 #include <assert.h>
  46 #include <string.h>
  47
  48 /* States*/
  49 #define NAMING  0
  50 #define GOTONE  1
  51 #define GOTTWO  2
  52 #define RESET   3
  53 /* Inputs */
  54 #define DIGIT   (4*0)
  55 #define END     (4*1)
  56 #define DELIM   (4*2)
  57 #define LETTER  (4*3)
  58
  59 void
  60 link_addr(addr, sdl)
  61         register const char *addr;
  62         register struct sockaddr_dl *sdl;
  63 {
  64         register char *cp = sdl->sdl_data;
  65         char *cplim = sdl->sdl_len + (char *)(void *)sdl;
  66         register int byte = 0, state = NAMING;
  67         register int newaddr = 0;       /* pacify gcc */
  68
  69         _DIAGASSERT(addr != NULL);
  70         _DIAGASSERT(sdl != NULL);
  71
  72         (void)memset(&sdl->sdl_family, 0, (size_t)sdl->sdl_len - 1);
  73         sdl->sdl_family = AF_LINK;
  74         do {
  75                 state &= ~LETTER;
  76                 if ((*addr >= '0') && (*addr <= '9')) {
  77                         newaddr = *addr - '0';
  78                 } else if ((*addr >= 'a') && (*addr <= 'f')) {
  79                         newaddr = *addr - 'a' + 10;
  80                 } else if ((*addr >= 'A') && (*addr <= 'F')) {
  81                         newaddr = *addr - 'A' + 10;
  82                 } else if (*addr == 0) {
  83                         state |= END;
  84                 } else if (state == NAMING &&
  85                            (((*addr >= 'A') && (*addr <= 'Z')) ||
  86                            ((*addr >= 'a') && (*addr <= 'z'))))
  87                         state |= LETTER;
  88                 else
  89                         state |= DELIM;
  90                 addr++;
  91                 switch (state /* | INPUT */) {
  92                 case NAMING | DIGIT:
  93                 case NAMING | LETTER:
  94                         *cp++ = addr[-1];
  95                         continue;
  96                 case NAMING | DELIM:
  97                         state = RESET;
  98                         sdl->sdl_nlen = cp - sdl->sdl_data;
  99                         continue;
 100                 case GOTTWO | DIGIT:
 101                         *cp++ = byte;
 102                         /* FALLTHROUGH */
 103                 case RESET | DIGIT:
 104                         state = GOTONE;
 105                         byte = newaddr;
 106                         continue;
 107                 case GOTONE | DIGIT:
 108                         state = GOTTWO;
 109                         byte = newaddr + (byte << 4);
 110                         continue;
 111                 default: /* | DELIM */
 112                         state = RESET;
 113                         *cp++ = byte;
 114                         byte = 0;
 115                         continue;
 116                 case GOTONE | END:
 117                 case GOTTWO | END:
 118                         *cp++ = byte;
 119                         /* FALLTHROUGH */
 120                 case RESET | END:
 121                         break;
 122                 }
 123                 break;
 124         } while (cp < cplim);
 125         sdl->sdl_alen = cp - LLADDR(sdl);
 126         newaddr = cp - (char *)(void *)sdl;
 127         if ((size_t) newaddr > sizeof(*sdl))
 128                 sdl->sdl_len = newaddr;
 129         return;
 130 }
 131
 132 static const char hexlist[16] = "0123456789abcdef";
 133
 134 char *
 135 link_ntoa(sdl)
 136         register const struct sockaddr_dl *sdl;
 137 {
 138         static char obuf[64];
 139         register char *out = obuf;
 140         register size_t i;
 141         const u_char *in = (const u_char *)CLLADDR(sdl);
 142         const u_char *inlim = in + sdl->sdl_alen;
 143         int firsttime = 1;
 144
 145         _DIAGASSERT(sdl != NULL);
 146
 147         if (sdl->sdl_nlen) {
 148                 (void)memcpy(obuf, sdl->sdl_data, (size_t)sdl->sdl_nlen);
 149                 out += sdl->sdl_nlen;
 150                 if (sdl->sdl_alen)
 151                         *out++ = ':';
 152         }
 153         while (in < inlim) {
 154                 if (firsttime)
 155                         firsttime = 0;
 156                 else
 157                         *out++ = '.';
 158                 i = *in++;
 159                 if (i > 0xf) {
 160                         out[1] = hexlist[i & 0xf];
 161                         i >>= 4;
 162                         out[0] = hexlist[i];
 163                         out += 2;
 164                 } else
 165                         *out++ = hexlist[i];
 166         }
 167         *out = 0;
 168         return (obuf);
 169 }