sys/lib/libsa/ether.c

   1 /*      $NetBSD: ether.c,v 1.23 2014/03/29 14:30:16 jakllsch Exp $      */
   2
   3 /*
   4  * Copyright (c) 1992 Regents of the University of California.
   5  * All rights reserved.
   6  *
   7  * This software was developed by the Computer Systems Engineering group
   8  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
   9  * contributed to Berkeley.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *      This product includes software developed by the University of
  22  *      California, Lawrence Berkeley Laboratory and its contributors.
  23  * 4. Neither the name of the University nor the names of its contributors
  24  *    may be used to endorse or promote products derived from this software
  25  *    without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  37  * SUCH DAMAGE.
  38  *
  39  * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp  (LBL)
  40  */
  41
  42 #include <sys/param.h>
  43 #include <sys/socket.h>
  44 #ifdef _STANDALONE
  45 #include <lib/libkern/libkern.h>
  46 #else
  47 #include <string.h>
  48 #endif
  49
  50 #include <net/if.h>
  51 #include <net/if_ether.h>
  52
  53 #include <netinet/in.h>
  54 #include <netinet/in_systm.h>
  55
  56 #include "stand.h"
  57 #include "net.h"
  58
  59 /* Caller must leave room for ethernet header in front!! */
  60 ssize_t
  61 sendether(struct iodesc *d, void *pkt, size_t len, u_char *dea, int etype)
  62 {
  63         ssize_t n;
  64         struct ether_header *eh;
  65
  66 #ifdef ETHER_DEBUG
  67         if (debug)
  68                 printf("sendether: called\n");
  69 #endif
  70
  71         eh = (struct ether_header *)pkt - 1;
  72         len += sizeof(*eh);
  73
  74         MACPY(d->myea, eh->ether_shost);                /* by byte */
  75         MACPY(dea, eh->ether_dhost);                    /* by byte */
  76         eh->ether_type = htons(etype);
  77
  78         n = netif_put(d, eh, len);
  79         if (n == -1 || (size_t)n < sizeof(*eh))
  80                 return -1;
  81
  82         n -= sizeof(*eh);
  83         return n;
  84 }
  85
  86 /*
  87  * Get a packet of any Ethernet type, with our address or
  88  * the broadcast address.  Save the Ether type in arg 5.
  89  * NOTE: Caller must leave room for the Ether header.
  90  */
  91 ssize_t
  92 readether(struct iodesc *d, void *pkt, size_t len, saseconds_t tleft,
  93         u_int16_t *etype)
  94 {
  95         ssize_t n;
  96         struct ether_header *eh;
  97
  98 #ifdef ETHER_DEBUG
  99         if (debug)
 100                 printf("readether: called\n");
 101 #endif
 102
 103         eh = (struct ether_header *)pkt - 1;
 104         len += sizeof(*eh);
 105
 106         n = netif_get(d, eh, len, tleft);
 107         if (n == -1 || (size_t)n < sizeof(*eh))
 108                 return -1;
 109
 110         /* Validate Ethernet address. */
 111         if (memcmp(d->myea, eh->ether_dhost, ETHER_ADDR_LEN) != 0 &&
 112             memcmp(bcea, eh->ether_dhost, ETHER_ADDR_LEN) != 0) {
 113 #ifdef ETHER_DEBUG
 114                 if (debug)
 115                         printf("readether: not ours (ea=%s)\n",
 116                             ether_sprintf(eh->ether_dhost));
 117 #endif
 118                 return -1;
 119         }
 120         *etype = ntohs(eh->ether_type);
 121
 122         n -= sizeof(*eh);
 123         return n;
 124 }