lib/libc/net/linkaddr.c

   1 /*      $NetBSD: linkaddr.c,v 1.16 2012/03/20 17:44:18 matt 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 1.16 2012/03/20 17:44:18 matt 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(const char *addr, struct sockaddr_dl *sdl)
  61 {
  62         register char *cp = sdl->sdl_data;
  63         char *cplim = sdl->sdl_len + (char *)(void *)sdl;
  64         int byte = 0, state = NAMING;
  65         size_t newaddr = 0;     /* pacify gcc */
  66
  67         _DIAGASSERT(addr != NULL);
  68         _DIAGASSERT(sdl != NULL);
  69
  70         (void)memset(&sdl->sdl_family, 0, (size_t)sdl->sdl_len - 1);
  71         sdl->sdl_family = AF_LINK;
  72         do {
  73                 state &= ~LETTER;
  74                 if ((*addr >= '0') && (*addr <= '9')) {
  75                         newaddr = *addr - '0';
  76                 } else if ((*addr >= 'a') && (*addr <= 'f')) {
  77                         newaddr = *addr - 'a' + 10;
  78                 } else if ((*addr >= 'A') && (*addr <= 'F')) {
  79                         newaddr = *addr - 'A' + 10;
  80                 } else if (*addr == 0) {
  81                         state |= END;
  82                 } else if (state == NAMING &&
  83                            (((*addr >= 'A') && (*addr <= 'Z')) ||
  84                            ((*addr >= 'a') && (*addr <= 'z'))))
  85                         state |= LETTER;
  86                 else
  87                         state |= DELIM;
  88                 addr++;
  89                 switch (state /* | INPUT */) {
  90                 case NAMING | DIGIT:
  91                 case NAMING | LETTER:
  92                         *cp++ = addr[-1];
  93                         continue;
  94                 case NAMING | DELIM:
  95                         state = RESET;
  96                         _DIAGASSERT(__type_fit(uint8_t, cp - sdl->sdl_data));
  97                         sdl->sdl_nlen = (uint8_t)(cp - sdl->sdl_data);
  98                         continue;
  99                 case GOTTWO | DIGIT:
 100                         *cp++ = byte;
 101                         /* FALLTHROUGH */
 102                 case RESET | DIGIT:
 103                         state = GOTONE;
 104                         byte = (int)newaddr;
 105                         continue;
 106                 case GOTONE | DIGIT:
 107                         state = GOTTWO;
 108                         byte = (int)newaddr + (byte << 4);
 109                         continue;
 110                 default: /* | DELIM */
 111                         state = RESET;
 112                         *cp++ = byte;
 113                         byte = 0;
 114                         continue;
 115                 case GOTONE | END:
 116                 case GOTTWO | END:
 117                         *cp++ = byte;
 118                         /* FALLTHROUGH */
 119                 case RESET | END:
 120                         break;
 121                 }
 122                 break;
 123         } while (cp < cplim);
 124
 125         _DIAGASSERT(__type_fit(uint8_t, cp - LLADDR(sdl)));
 126         sdl->sdl_alen = (uint8_t)(cp - LLADDR(sdl));
 127         newaddr = cp - (char *)(void *)sdl;
 128         if (newaddr > sizeof(*sdl)) {
 129                 _DIAGASSERT(__type_fit(uint8_t, newaddr));
 130                 sdl->sdl_len = (uint8_t)newaddr;
 131         }
 132         return;
 133 }
 134
 135 static const char hexlist[16] = "0123456789abcdef";
 136
 137 char *
 138 link_ntoa(const struct sockaddr_dl *sdl)
 139 {
 140         static char obuf[64];
 141         register char *out = obuf;
 142         register size_t i;
 143         const u_char *in = (const u_char *)CLLADDR(sdl);
 144         const u_char *inlim = in + sdl->sdl_alen;
 145         int firsttime = 1;
 146
 147         _DIAGASSERT(sdl != NULL);
 148
 149         if (sdl->sdl_nlen) {
 150                 (void)memcpy(obuf, sdl->sdl_data, (size_t)sdl->sdl_nlen);
 151                 out += sdl->sdl_nlen;
 152                 if (sdl->sdl_alen)
 153                         *out++ = ':';
 154         }
 155         while (in < inlim) {
 156                 if (firsttime)
 157                         firsttime = 0;
 158                 else
 159                         *out++ = '.';
 160                 i = *in++;
 161                 if (i > 0xf) {
 162                         out[1] = hexlist[i & 0xf];
 163                         i >>= 4;
 164                         out[0] = hexlist[i];
 165                         out += 2;
 166                 } else
 167                         *out++ = hexlist[i];
 168         }
 169         *out = 0;
 170         return (obuf);
 171 }