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1/* $OpenBSD: ether.c,v 1.10 2014/11/19 20:28:56 miod Exp $ */
2/* $NetBSD: ether.c,v 1.8 1996/10/13 02:29:00 christos 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. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by the University of
23 * California, Lawrence Berkeley Laboratory and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 *
40 * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp (LBL)
41 */
42
43#include <sys/param.h>
44#include <sys/socket.h>
45
46#include <net/if.h>
47
48#include <netinet/in.h>
49#include <netinet/if_ether.h>
50#include <netinet/ip.h>
51
52#include "stand.h"
53#include "net.h"
54#include "netif.h"
55
56/* Caller must leave room for ethernet header in front!! */
57ssize_t
58sendether(struct iodesc *d, void *pkt, size_t len, u_char *dea, int etype)
59{
60 ssize_t n;
61 struct ether_header *eh;
62
63#ifdef ETHER_DEBUG
64 if (debug)
65 printf("sendether: called\n");
66#endif
67
68 eh = (struct ether_header *)pkt - 1;
69 len += sizeof(*eh);
70
71 MACPY(d->myea, eh->ether_shost); /* by byte */
72 MACPY(dea, eh->ether_dhost); /* by byte */
73 eh->ether_type = htons(etype);
74
75 n = netif_put(d, eh, len);
76 if (n < 0 || (size_t)n < sizeof(*eh))
77 return (-1);
78
79 n -= sizeof(*eh);
80 return (n);
81}
82
83/*
84 * Get a packet of any Ethernet type, with our address or
85 * the broadcast address. Save the Ether type in arg 5.
86 * NOTE: Caller must leave room for the Ether header.
87 */
88ssize_t
89readether(struct iodesc *d, void *pkt, size_t len, time_t tleft,
90 u_int16_t *etype)
91{
92 ssize_t n;
93 struct ether_header *eh;
94
95#ifdef ETHER_DEBUG
96 if (debug)
97 printf("readether: called\n");
98#endif
99
100 eh = (struct ether_header *)pkt - 1;
101 len += sizeof(*eh);
102
103 n = netif_get(d, eh, len, tleft);
104 if (n < 0 || (size_t)n < sizeof(*eh))
105 return (-1);
106
107 /* Validate Ethernet address. */
108 if (bcmp(d->myea, eh->ether_dhost, 6) != 0 &&
109 bcmp(bcea, eh->ether_dhost, 6) != 0) {
110#ifdef ETHER_DEBUG
111 if (debug)
112 printf("readether: not ours (ea=%s)\n",
113 ether_sprintf(eh->ether_dhost));
114#endif
115 return (-1);
116 }
117 *etype = ntohs(eh->ether_type);
118
119 n -= sizeof(*eh);
120 return (n);
121}
122
123/*
124 * Convert Ethernet address to printable (loggable) representation.
125 */
126static const char digits[] = "0123456789abcdef";
127const char *
128ether_sprintf(const u_char *ap)
129{
130 int i;
131 static char etherbuf[18];
132 char *cp = etherbuf;
133
134 for (i = 0; i < 6; i++) {
135 *cp++ = digits[*ap >> 4];
136 *cp++ = digits[*ap++ & 0xf];
137 *cp++ = ':';
138 }
139 *--cp = 0;
140 return (etherbuf);
141}