usr/src/boot/lib/libstand/ether.c

   1 /*      $NetBSD: ether.c,v 1.11 1997/07/07 15:52:50 drochner 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  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp  (LBL)
  36  */
  37
  38 #include <sys/cdefs.h>
  39
  40 #include <sys/param.h>
  41 #include <sys/socket.h>
  42 #include <string.h>
  43
  44 #include <net/if.h>
  45 #include <netinet/in.h>
  46 #include <netinet/if_ether.h>
  47 #include <netinet/in_systm.h>
  48 #include <netinet/ip.h>
  49
  50 #include "stand.h"
  51 #include "net.h"
  52 #include "netif.h"
  53
  54 /* Caller must leave room for ethernet header in front!! */
  55 ssize_t
  56 sendether(struct iodesc *d, void *pkt, size_t len, uint8_t *dea, int etype)
  57 {
  58         ssize_t n;
  59         struct ether_header *eh;
  60
  61 #ifdef ETHER_DEBUG
  62         if (debug)
  63                 printf("sendether: called\n");
  64 #endif
  65
  66         eh = (struct ether_header *)pkt - 1;
  67         len += sizeof(*eh);
  68
  69         MACPY(d->myea, eh->ether_shost);                /* by byte */
  70         MACPY(dea, eh->ether_dhost);                    /* by byte */
  71         eh->ether_type = htons(etype);
  72
  73         n = netif_put(d, eh, len);
  74         if (n == -1 || n < sizeof(*eh))
  75                 return (-1);
  76
  77         n -= sizeof(*eh);
  78         return (n);
  79 }
  80
  81 /*
  82  * Get a packet of any Ethernet type, with our address or
  83  * the broadcast address.  Save the Ether type in etype.
  84  * Unless there is an error, we pass the whole packet and the unencapsulated
  85  * data.
  86  */
  87 ssize_t
  88 readether(struct iodesc *d, void **pkt, void **payload, time_t tleft,
  89     uint16_t *etype)
  90 {
  91         ssize_t n;
  92         struct ether_header *eh;
  93         void *ptr;
  94
  95 #ifdef ETHER_DEBUG
  96         if (debug)
  97                 printf("readether: called\n");
  98 #endif
  99
 100         ptr = NULL;
 101         n = netif_get(d, &ptr, tleft);
 102         if (n == -1 || n < sizeof(*eh)) {
 103                 free(ptr);
 104                 return (-1);
 105         }
 106
 107         eh = (struct ether_header *)((uintptr_t)ptr + ETHER_ALIGN);
 108         /* Validate Ethernet address. */
 109         if (bcmp(d->myea, eh->ether_dhost, 6) != 0 &&
 110             bcmp(bcea, eh->ether_dhost, 6) != 0) {
 111 #ifdef ETHER_DEBUG
 112                 if (debug)
 113                         printf("readether: not ours (ea=%s)\n",
 114                             ether_sprintf(eh->ether_dhost));
 115 #endif
 116                 free(ptr);
 117                 return (-1);
 118         }
 119
 120         *pkt = ptr;
 121         *payload = (void *)((uintptr_t)eh + sizeof(*eh));
 122         *etype = ntohs(eh->ether_type);
 123
 124         n -= sizeof(*eh);
 125         return (n);
 126 }
 127
 128 /*
 129  * Convert Ethernet address to printable (loggable) representation.
 130  */
 131 static char digits[] = "0123456789abcdef";
 132 char *
 133 ether_sprintf(ap)
 134         u_char *ap;
 135 {
 136         int i;
 137         static char etherbuf[18];
 138         char *cp = etherbuf;
 139
 140         for (i = 0; i < 6; i++) {
 141                 *cp++ = digits[*ap >> 4];
 142                 *cp++ = digits[*ap++ & 0xf];
 143                 *cp++ = ':';
 144         }
 145         *--cp = 0;
 146         return (etherbuf);
 147 }