summaryrefslogtreecommitdiffstats
path: root/contrib/tcpdump/print-ether.c
blob: 6ca59fd8f290c0c0ba3ba11a5c0f59ac99d822a2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
/*
 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University nor the names of its contributors may be used to endorse
 * or promote products derived from this software without specific prior
 * written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * $FreeBSD$
 */
#ifndef lint
static const char rcsid[] =
    "@(#) $Header: /tcpdump/master/tcpdump/print-ether.c,v 1.65 2001/07/04 22:03:14 fenner Exp $ (LBL)";
#endif

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>

struct mbuf;
struct rtentry;

#include <netinet/in.h>

#include <stdio.h>
#include <pcap.h>

#include "interface.h"
#include "addrtoname.h"
#include "ethertype.h"

#include "ether.h"

const u_char *packetp;
const u_char *snapend;

static inline void
ether_print(register const u_char *bp, u_int length)
{
	register const struct ether_header *ep;

	ep = (const struct ether_header *)bp;
	if (qflag)
		(void)printf("%s %s %d: ",
			     etheraddr_string(ESRC(ep)),
			     etheraddr_string(EDST(ep)),
			     length);
	else
		(void)printf("%s %s %s %d: ",
			     etheraddr_string(ESRC(ep)),
			     etheraddr_string(EDST(ep)),
			     etherproto_string(ep->ether_type),
			     length);
}

/*
 * This is the top level routine of the printer.  'p' is the points
 * to the ether header of the packet, 'h->tv' is the timestamp,
 * 'h->length' is the length of the packet off the wire, and 'h->caplen'
 * is the number of bytes actually captured.
 */
void
ether_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
{
	u_int caplen = h->caplen;
	u_int length = h->len;
	struct ether_header *ep;
	u_short ether_type;
	u_short extracted_ethertype;

	++infodelay;
	ts_print(&h->ts);

	if (caplen < ETHER_HDRLEN) {
		printf("[|ether]");
		goto out;
	}

	if (eflag)
		ether_print(p, length);

	/*
	 * Some printers want to get back at the ethernet addresses,
	 * and/or check that they're not walking off the end of the packet.
	 * Rather than pass them all the way down, we set these globals.
	 */
	packetp = p;
	snapend = p + caplen;

	length -= ETHER_HDRLEN;
	caplen -= ETHER_HDRLEN;
	ep = (struct ether_header *)p;
	p += ETHER_HDRLEN;

	ether_type = ntohs(ep->ether_type);

	/*
	 * Is it (gag) an 802.3 encapsulation?
	 */
	extracted_ethertype = 0;
	if (ether_type <= ETHERMTU) {
		/* Try to print the LLC-layer header & higher layers */
		if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
		    &extracted_ethertype) == 0) {
			/* ether_type not known, print raw packet */
			if (!eflag)
				ether_print((u_char *)ep, length + ETHER_HDRLEN);
			if (extracted_ethertype) {
				printf("(LLC %s) ",
			       etherproto_string(htons(extracted_ethertype)));
			}
			if (!xflag && !qflag)
				default_print(p, caplen);
		}
	} else if (ether_encap_print(ether_type, p, length, caplen,
	    &extracted_ethertype) == 0) {
		/* ether_type not known, print raw packet */
		if (!eflag)
			ether_print((u_char *)ep, length + ETHER_HDRLEN);
		if (!xflag && !qflag)
			default_print(p, caplen);
	}
	if (xflag)
		default_print(p, caplen);
 out:
	putchar('\n');
	--infodelay;
	if (infoprint)
		info(0);
}

/*
 * Prints the packet encapsulated in an Ethernet data segment
 * (or an equivalent encapsulation), given the Ethernet type code.
 *
 * Returns non-zero if it can do so, zero if the ethertype is unknown.
 *
 * The Ethernet type code is passed through a pointer; if it was
 * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of
 * the 802.1Q payload, for the benefit of lower layers that might
 * want to know what it is.
 */

int
ether_encap_print(u_short ethertype, const u_char *p,
    u_int length, u_int caplen, u_short *extracted_ethertype)
{
 recurse:
	*extracted_ethertype = ethertype;

	switch (ethertype) {

	case ETHERTYPE_IP:
		ip_print(p, length);
		return (1);

#ifdef INET6
	case ETHERTYPE_IPV6:
		ip6_print(p, length);
		return (1);
#endif /*INET6*/

	case ETHERTYPE_ARP:
	case ETHERTYPE_REVARP:
		arp_print(p, length, caplen);
		return (1);

	case ETHERTYPE_DN:
		decnet_print(p, length, caplen);
		return (1);

	case ETHERTYPE_ATALK:
		if (vflag)
			fputs("et1 ", stdout);
		atalk_print(p, length);
		return (1);

	case ETHERTYPE_AARP:
		aarp_print(p, length);
		return (1);

	case ETHERTYPE_IPX:
		ipx_print(p, length);
		return (1);

	case ETHERTYPE_8021Q:
		printf("802.1Q vlan#%d P%d%s ",
		       ntohs(*(u_int16_t *)p) & 0xfff,
		       ntohs(*(u_int16_t *)p) >> 13,
		       (ntohs(*(u_int16_t *)p) & 0x1000) ? " CFI" : "");
		ethertype = ntohs(*(u_int16_t *)(p + 2));
		p += 4;
		length -= 4;
		caplen -= 4;
		if (ethertype > ETHERMTU)
			goto recurse;

		*extracted_ethertype = 0;

		if (llc_print(p, length, caplen, p - 18, p - 12,
		    extracted_ethertype) == 0) {
			/* ether_type not known, print raw packet */
			if (!eflag)
				ether_print(p - 18, length + 4);
			if (*extracted_ethertype) {
				printf("(LLC %s) ",
			       etherproto_string(htons(*extracted_ethertype)));
			}
			if (!xflag && !qflag)
				default_print(p - 18, caplen + 4);
		}
		return (1);

	case ETHERTYPE_PPPOED:
	case ETHERTYPE_PPPOES:
	case ETHERTYPE_PPPOED2:
	case ETHERTYPE_PPPOES2:
		pppoe_print(p, length);
 		return (1);
 
	case ETHERTYPE_PPP:
		printf("ppp");
		if (length) {
			printf(": ");
			ppp_print(p, length);
		}
		return (1);

	case ETHERTYPE_MPLS:
	case ETHERTYPE_MPLS_MULTI:
		mpls_print(p, length);
		return (1);

	case ETHERTYPE_LAT:
	case ETHERTYPE_SCA:
	case ETHERTYPE_MOPRC:
	case ETHERTYPE_MOPDL:
		/* default_print for now */
	default:
		return (0);
	}
}
OpenPOWER on IntegriCloud