lib/libstand/ether.c

   1 /*      $NetBSD: ether.c,v 1.11 1997/07/07 15:52:50 drochner Exp $      */
   2 /* $DragonFly: src/lib/libstand/ether.c,v 1.3 2005/12/11 02:27:26 swildner Exp $                                                                */
   3
   4 /*
   5  * Copyright (c) 1992 Regents of the University of California.
   6  * All rights reserved.
   7  *
   8  * This software was developed by the Computer Systems Engineering group
   9  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
  10  * contributed to Berkeley.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp  (LBL)
  37  */
  38
  39 #include <sys/param.h>
  40 #include <sys/socket.h>
  41 #include <string.h>
  42
  43 #include <net/if.h>
  44 #include <netinet/in.h>
  45 #include <netinet/if_ether.h>
  46 #include <netinet/in_systm.h>
  47 #include <netinet/ip.h>
  48
  49 #include "stand.h"
  50 #include "net.h"
  51 #include "netif.h"
  52
  53 /* Caller must leave room for ethernet header in front!! */
  54 ssize_t
  55 sendether(struct iodesc *d, void *pkt, size_t len, u_char *dea, int etype)
  56 {
  57         ssize_t n;
  58         struct ether_header *eh;
  59
  60 #ifdef ETHER_DEBUG
  61         if (debug)
  62                 printf("sendether: called\n");
  63 #endif
  64
  65         eh = (struct ether_header *)pkt - 1;
  66         len += sizeof(*eh);
  67
  68         MACPY(d->myea, eh->ether_shost);                /* by byte */
  69         MACPY(dea, eh->ether_dhost);                    /* by byte */
  70         eh->ether_type = htons(etype);
  71
  72         n = netif_put(d, eh, len);
  73         if (n == -1 || n < sizeof(*eh))
  74                 return (-1);
  75
  76         n -= sizeof(*eh);
  77         return (n);
  78 }
  79
  80 /*
  81  * Get a packet of any Ethernet type, with our address or
  82  * the broadcast address.  Save the Ether type in arg 5.
  83  * NOTE: Caller must leave room for the Ether header.
  84  */
  85 ssize_t
  86 readether(struct iodesc *d, void *pkt, size_t len, time_t tleft,
  87           u_int16_t *etype)
  88 {
  89         ssize_t n;
  90         struct ether_header *eh;
  91
  92 #ifdef ETHER_DEBUG
  93         if (debug)
  94                 printf("readether: called\n");
  95 #endif
  96
  97         eh = (struct ether_header *)pkt - 1;
  98         len += sizeof(*eh);
  99
 100         n = netif_get(d, eh, len, tleft);
 101         if (n == -1 || n < sizeof(*eh))
 102                 return (-1);
 103
 104         /* Validate Ethernet address. */
 105         if (bcmp(d->myea, eh->ether_dhost, ETHER_ADDR_LEN) != 0 &&
 106             bcmp(bcea, eh->ether_dhost, ETHER_ADDR_LEN) != 0) {
 107 #ifdef ETHER_DEBUG
 108                 if (debug)
 109                         printf("readether: not ours (ea=%s)\n",
 110                             ether_sprintf(eh->ether_dhost));
 111 #endif
 112                 return (-1);
 113         }
 114         *etype = ntohs(eh->ether_type);
 115
 116         n -= sizeof(*eh);
 117         return (n);
 118 }
 119
 120 /*
 121  * Convert Ethernet address to printable (loggable) representation.
 122  */
 123 static char digits[] = "0123456789abcdef";
 124 char *
 125 ether_sprintf(u_char *ap)
 126 {
 127         int i;
 128         static char etherbuf[3 * ETHER_ADDR_LEN];
 129         char *cp = etherbuf;
 130
 131         for (i = 0; i < ETHER_ADDR_LEN; i++) {
 132                 *cp++ = digits[*ap >> 4];
 133                 *cp++ = digits[*ap++ & 0xf];
 134                 *cp++ = ':';
 135         }
 136         *--cp = 0;
 137         return (etherbuf);
 138 }