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
36 #include <sys/param.h>
37 #include <sys/socket.h>
38 #include <string.h>
39
40 #include <net/if.h>
41 #include <netinet/in.h>
42 #include <netinet/if_ether.h>
43 #include <netinet/in_systm.h>
44 #include <netinet/ip.h>
45
46 #include "stand.h"
47 #include "net.h"
48 #include "netif.h"
49
50 /* Caller must leave room for ethernet header in front!! */
51 ssize_t
sendether(struct iodesc * d,void * pkt,size_t len,uint8_t * dea,int etype)52 sendether(struct iodesc *d, void *pkt, size_t len, uint8_t *dea, int etype)
53 {
54 ssize_t n;
55 struct ether_header *eh;
56
57 #ifdef ETHER_DEBUG
58 if (debug)
59 printf("sendether: called\n");
60 #endif
61
62 eh = (struct ether_header *)pkt - 1;
63 len += sizeof(*eh);
64
65 MACPY(d->myea, eh->ether_shost); /* by byte */
66 MACPY(dea, eh->ether_dhost); /* by byte */
67 eh->ether_type = htons(etype);
68
69 n = netif_put(d, eh, len);
70 if (n == -1 || n < sizeof(*eh))
71 return (-1);
72
73 n -= sizeof(*eh);
74 return (n);
75 }
76
77 /*
78 * Get a packet of any Ethernet type, with our address or
79 * the broadcast address. Save the Ether type in etype.
80 * Unless there is an error, we pass the whole packet and the unencapsulated
81 * data.
82 */
83 ssize_t
readether(struct iodesc * d,void ** pkt,void ** payload,time_t tleft,uint16_t * etype)84 readether(struct iodesc *d, void **pkt, void **payload, time_t tleft,
85 uint16_t *etype)
86 {
87 ssize_t n;
88 struct ether_header *eh;
89 void *ptr;
90
91 #ifdef ETHER_DEBUG
92 if (debug)
93 printf("readether: called\n");
94 #endif
95
96 ptr = NULL;
97 n = netif_get(d, &ptr, tleft);
98 if (n == -1 || n < sizeof(*eh)) {
99 free(ptr);
100 return (-1);
101 }
102
103 eh = (struct ether_header *)((uintptr_t)ptr + ETHER_ALIGN);
104 /* Validate Ethernet address. */
105 if (bcmp(d->myea, eh->ether_dhost, 6) != 0 &&
106 bcmp(bcea, eh->ether_dhost, 6) != 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 free(ptr);
113 return (-1);
114 }
115
116 *pkt = ptr;
117 *payload = (void *)((uintptr_t)eh + sizeof(*eh));
118 *etype = ntohs(eh->ether_type);
119
120 n -= sizeof(*eh);
121 return (n);
122 }
123
124 /*
125 * Convert Ethernet address to printable (loggable) representation.
126 */
127 static char digits[] = "0123456789abcdef";
128 char *
ether_sprintf(u_char * ap)129 ether_sprintf(u_char *ap)
130 {
131 int i;
132 static char etherbuf[18];
133 char *cp = etherbuf;
134
135 for (i = 0; i < 6; i++) {
136 *cp++ = digits[*ap >> 4];
137 *cp++ = digits[*ap++ & 0xf];
138 *cp++ = ':';
139 }
140 *--cp = 0;
141 return (etherbuf);
142 }
143