gen.subproj/ether_addr.c

   1 /*
   2  * Copyright (c) 1999-2008 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.1 (the "License").  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 #if !defined(lint) && defined(SCCSIDS)
  25 static  char sccsid[] = "@(#)ether_addr.c       1.2 88/05/10 4.0NFSSRC; from 1.9 88/02/08 Copyr 1985 Sun Micro";
  26 #endif
  27
  28 /*
  29  * Copyright (c) 1985 by Sun Microsystems, Inc.
  30  *
  31  * All routines necessary to deal with the file /etc/ethers.  The file
  32  * contains mappings from 48 bit ethernet addresses to their corresponding
  33  * hosts name.  The addresses have an ascii representation of the form
  34  * "x:x:x:x:x:x" where x is a hex number between 0x00 and 0xff;  the
  35  * bytes are always in network order.
  36  */
  37
  38 #include <stdlib.h>
  39 #include <string.h>
  40 #include <stdio.h>
  41 #include <sys/types.h>
  42 #include <sys/socket.h>
  43 #include <net/if.h>
  44 #include <netinet/in.h>
  45 #include <netinet/if_ether.h>
  46
  47 /*
  48  * Parses a line from /etc/ethers into its components.  The line has the form
  49  * 8:0:20:1:17:c8       krypton
  50  * where the first part is a 48 bit ethernet addrerss and the second is
  51  * the corresponding hosts name.
  52  * Returns zero if successful, non-zero otherwise.
  53  */
  54 int
  55 ether_line(const char *s, struct ether_addr *e, char *hostname)
  56 {
  57         int i;
  58         unsigned int t[6];
  59
  60         i = sscanf(s, " %x:%x:%x:%x:%x:%x %s", &t[0], &t[1], &t[2], &t[3], &t[4], &t[5], hostname);
  61         if (i != 7) return (7 - i);
  62
  63         for (i = 0; i < 6; i++) e->ether_addr_octet[i] = t[i];
  64         return 0;
  65 }
  66
  67 /*
  68  * Converts a 48 bit ethernet number to its string representation.
  69  */
  70 #define EI(i) (unsigned int)(e->ether_addr_octet[(i)])
  71 char *
  72 ether_ntoa(const struct ether_addr *e)
  73 {
  74         static char *s;
  75
  76         if (s == 0)
  77         {
  78                 s = (char *)malloc(18);
  79                 if (s == 0) return NULL;
  80         }
  81
  82         s[0] = 0;
  83         sprintf(s, "%x:%x:%x:%x:%x:%x", EI(0), EI(1), EI(2), EI(3), EI(4), EI(5));
  84         return s;
  85 }
  86
  87 /*
  88  * Converts a ethernet address representation back into its 48 bits.
  89  */
  90 struct ether_addr *
  91 ether_aton(const char *s)
  92 {
  93         static struct ether_addr *ep;
  94         int i;
  95         unsigned int t[6];
  96
  97         if (ep == 0)
  98         {
  99                 ep = (struct ether_addr *)calloc(1, sizeof (struct ether_addr));
 100                 if (ep == 0) return NULL;
 101         }
 102
 103         i = sscanf(s, " %x:%x:%x:%x:%x:%x", &t[0], &t[1], &t[2], &t[3], &t[4], &t[5]);
 104         if (i != 6) return NULL;
 105
 106         for (i = 0; i < 6; i++) ep->ether_addr_octet[i] = t[i];
 107         return ep;
 108 }