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 * 3. 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 __FBSDID("$FreeBSD$");
40
41 #include <sys/param.h>
42 #include <sys/socket.h>
43 #include <string.h>
44
45 #include <net/if.h>
46 #include <netinet/in.h>
47 #include <netinet/if_ether.h>
48 #include <netinet/in_systm.h>
49 #include <netinet/ip.h>
50
51 #include "stand.h"
52 #include "net.h"
53 #include "netif.h"
54
55 /* Caller must leave room for ethernet header in front!! */
56 ssize_t
sendether(struct iodesc * d,void * pkt,size_t len,uint8_t * dea,int etype)57 sendether(struct iodesc *d, void *pkt, size_t len, uint8_t *dea, int etype)
58 {
59 ssize_t n;
60 struct ether_header *eh;
61
62 #ifdef ETHER_DEBUG
63 if (debug)
64 printf("sendether: called\n");
65 #endif
66
67 eh = (struct ether_header *)pkt - 1;
68 len += sizeof(*eh);
69
70 MACPY(d->myea, eh->ether_shost); /* by byte */
71 MACPY(dea, eh->ether_dhost); /* by byte */
72 eh->ether_type = htons(etype);
73
74 n = netif_put(d, eh, len);
75 if (n == -1 || n < sizeof(*eh))
76 return (-1);
77
78 n -= sizeof(*eh);
79 return (n);
80 }
81
82 /*
83 * Get a packet of any Ethernet type, with our address or
84 * the broadcast address. Save the Ether type in etype.
85 * Unless there is an error, we pass the whole packet and the unencapsulated
86 * data.
87 */
88 ssize_t
readether(struct iodesc * d,void ** pkt,void ** payload,time_t tleft,uint16_t * etype)89 readether(struct iodesc *d, void **pkt, void **payload, time_t tleft,
90 uint16_t *etype)
91 {
92 ssize_t n;
93 struct ether_header *eh;
94 void *ptr;
95
96 #ifdef ETHER_DEBUG
97 if (debug)
98 printf("readether: called\n");
99 #endif
100
101 ptr = NULL;
102 n = netif_get(d, &ptr, tleft);
103 if (n == -1 || n < sizeof(*eh)) {
104 free(ptr);
105 return (-1);
106 }
107
108 eh = (struct ether_header *)((uintptr_t)ptr + ETHER_ALIGN);
109 /* Validate Ethernet address. */
110 if (bcmp(d->myea, eh->ether_dhost, 6) != 0 &&
111 bcmp(bcea, eh->ether_dhost, 6) != 0) {
112 #ifdef ETHER_DEBUG
113 if (debug)
114 printf("readether: not ours (ea=%s)\n",
115 ether_sprintf(eh->ether_dhost));
116 #endif
117 free(ptr);
118 return (-1);
119 }
120
121 *pkt = ptr;
122 *payload = (void *)((uintptr_t)eh + sizeof(*eh));
123 *etype = ntohs(eh->ether_type);
124
125 n -= sizeof(*eh);
126 return (n);
127 }
128
129 /*
130 * Convert Ethernet address to printable (loggable) representation.
131 */
132 static char digits[] = "0123456789abcdef";
133 char *
ether_sprintf(u_char * ap)134 ether_sprintf(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 }
148