1/*
2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 *
21 * Hacked version of print-ether.c  Larry Lile <lile@stdio.com>
22 *
23 * Further tweaked to more closely resemble print-fddi.c
24 *	Guy Harris <guy@alum.mit.edu>
25 */
26
27#define NETDISSECT_REWORKED
28#ifdef HAVE_CONFIG_H
29#include "config.h"
30#endif
31
32#include <tcpdump-stdinc.h>
33
34#include <string.h>
35
36#include "interface.h"
37#include "extract.h"
38#include "addrtoname.h"
39#include "ether.h"
40
41/*
42 * Copyright (c) 1998, Larry Lile
43 * All rights reserved.
44 *
45 * Redistribution and use in source and binary forms, with or without
46 * modification, are permitted provided that the following conditions
47 * are met:
48 * 1. Redistributions of source code must retain the above copyright
49 *    notice unmodified, this list of conditions, and the following
50 *    disclaimer.
51 * 2. Redistributions in binary form must reproduce the above copyright
52 *    notice, this list of conditions and the following disclaimer in the
53 *    documentation and/or other materials provided with the distribution.
54 *
55 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
56 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
57 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
58 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
59 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
60 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
61 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
62 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
63 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
64 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
65 * SUCH DAMAGE.
66 *
67 */
68
69#define TOKEN_HDRLEN		14
70#define TOKEN_RING_MAC_LEN	6
71#define ROUTING_SEGMENT_MAX	16
72#define IS_SOURCE_ROUTED(trp)	((trp)->token_shost[0] & 0x80)
73#define FRAME_TYPE(trp)		(((trp)->token_fc & 0xC0) >> 6)
74#define TOKEN_FC_LLC		1
75
76#define BROADCAST(trp)		((EXTRACT_16BITS(&(trp)->token_rcf) & 0xE000) >> 13)
77#define RIF_LENGTH(trp)		((EXTRACT_16BITS(&(trp)->token_rcf) & 0x1f00) >> 8)
78#define DIRECTION(trp)		((EXTRACT_16BITS(&(trp)->token_rcf) & 0x0080) >> 7)
79#define LARGEST_FRAME(trp)	((EXTRACT_16BITS(&(trp)->token_rcf) & 0x0070) >> 4)
80#define RING_NUMBER(trp, x)	((EXTRACT_16BITS(&(trp)->token_rseg[x]) & 0xfff0) >> 4)
81#define BRIDGE_NUMBER(trp, x)	((EXTRACT_16BITS(&(trp)->token_rseg[x]) & 0x000f))
82#define SEGMENT_COUNT(trp)	((int)((RIF_LENGTH(trp) - 2) / 2))
83
84struct token_header {
85	uint8_t  token_ac;
86	uint8_t  token_fc;
87	uint8_t  token_dhost[TOKEN_RING_MAC_LEN];
88	uint8_t  token_shost[TOKEN_RING_MAC_LEN];
89	uint16_t token_rcf;
90	uint16_t token_rseg[ROUTING_SEGMENT_MAX];
91};
92
93static const char tstr[] = "[|token-ring]";
94
95/* Extract src, dst addresses */
96static inline void
97extract_token_addrs(const struct token_header *trp, char *fsrc, char *fdst)
98{
99	memcpy(fdst, (const char *)trp->token_dhost, 6);
100	memcpy(fsrc, (const char *)trp->token_shost, 6);
101}
102
103/*
104 * Print the TR MAC header
105 */
106static inline void
107token_hdr_print(netdissect_options *ndo,
108                register const struct token_header *trp, register u_int length,
109                register const u_char *fsrc, register const u_char *fdst)
110{
111	const char *srcname, *dstname;
112
113	srcname = etheraddr_string(ndo, fsrc);
114	dstname = etheraddr_string(ndo, fdst);
115
116	if (ndo->ndo_vflag)
117		ND_PRINT((ndo, "%02x %02x %s %s %d: ",
118		       trp->token_ac,
119		       trp->token_fc,
120		       srcname, dstname,
121		       length));
122	else
123		ND_PRINT((ndo, "%s %s %d: ", srcname, dstname, length));
124}
125
126static const char *broadcast_indicator[] = {
127	"Non-Broadcast", "Non-Broadcast",
128	"Non-Broadcast", "Non-Broadcast",
129	"All-routes",    "All-routes",
130	"Single-route",  "Single-route"
131};
132
133static const char *direction[] = {
134	"Forward", "Backward"
135};
136
137static const char *largest_frame[] = {
138	"516",
139	"1500",
140	"2052",
141	"4472",
142	"8144",
143	"11407",
144	"17800",
145	"??"
146};
147
148u_int
149token_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
150{
151	const struct token_header *trp;
152	u_short extracted_ethertype;
153	struct ether_header ehdr;
154	u_int route_len = 0, hdr_len = TOKEN_HDRLEN;
155	int seg;
156
157	trp = (const struct token_header *)p;
158
159	if (caplen < TOKEN_HDRLEN) {
160		ND_PRINT((ndo, "%s", tstr));
161		return hdr_len;
162	}
163
164	/*
165	 * Get the TR addresses into a canonical form
166	 */
167	extract_token_addrs(trp, (char*)ESRC(&ehdr), (char*)EDST(&ehdr));
168
169	/* Adjust for source routing information in the MAC header */
170	if (IS_SOURCE_ROUTED(trp)) {
171		/* Clear source-routed bit */
172		*ESRC(&ehdr) &= 0x7f;
173
174		if (ndo->ndo_eflag)
175			token_hdr_print(ndo, trp, length, ESRC(&ehdr), EDST(&ehdr));
176
177		if (caplen < TOKEN_HDRLEN + 2) {
178			ND_PRINT((ndo, "%s", tstr));
179			return hdr_len;
180		}
181		route_len = RIF_LENGTH(trp);
182		hdr_len += route_len;
183		if (caplen < hdr_len) {
184			ND_PRINT((ndo, "%s", tstr));
185			return hdr_len;
186		}
187		if (ndo->ndo_vflag) {
188			ND_PRINT((ndo, "%s ", broadcast_indicator[BROADCAST(trp)]));
189			ND_PRINT((ndo, "%s", direction[DIRECTION(trp)]));
190
191			for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
192				ND_PRINT((ndo, " [%d:%d]", RING_NUMBER(trp, seg),
193				    BRIDGE_NUMBER(trp, seg)));
194		} else {
195			ND_PRINT((ndo, "rt = %x", EXTRACT_16BITS(&trp->token_rcf)));
196
197			for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
198				ND_PRINT((ndo, ":%x", EXTRACT_16BITS(&trp->token_rseg[seg])));
199		}
200		ND_PRINT((ndo, " (%s) ", largest_frame[LARGEST_FRAME(trp)]));
201	} else {
202		if (ndo->ndo_eflag)
203			token_hdr_print(ndo, trp, length, ESRC(&ehdr), EDST(&ehdr));
204	}
205
206	/* Skip over token ring MAC header and routing information */
207	length -= hdr_len;
208	p += hdr_len;
209	caplen -= hdr_len;
210
211	/* Frame Control field determines interpretation of packet */
212	if (FRAME_TYPE(trp) == TOKEN_FC_LLC) {
213		/* Try to print the LLC-layer header & higher layers */
214		if (llc_print(ndo, p, length, caplen, ESRC(&ehdr), EDST(&ehdr),
215		    &extracted_ethertype) == 0) {
216			/* ether_type not known, print raw packet */
217			if (!ndo->ndo_eflag)
218				token_hdr_print(ndo, trp,
219				    length + TOKEN_HDRLEN + route_len,
220				    ESRC(&ehdr), EDST(&ehdr));
221			if (extracted_ethertype) {
222				ND_PRINT((ndo, "(LLC %s) ",
223			etherproto_string(htons(extracted_ethertype))));
224			}
225			if (!ndo->ndo_suppress_default_print)
226				ND_DEFAULTPRINT(p, caplen);
227		}
228	} else {
229		/* Some kinds of TR packet we cannot handle intelligently */
230		/* XXX - dissect MAC packets if frame type is 0 */
231		if (!ndo->ndo_eflag)
232			token_hdr_print(ndo, trp, length + TOKEN_HDRLEN + route_len,
233			    ESRC(&ehdr), EDST(&ehdr));
234		if (!ndo->ndo_suppress_default_print)
235			ND_DEFAULTPRINT(p, caplen);
236	}
237	return (hdr_len);
238}
239
240/*
241 * This is the top level routine of the printer.  'p' points
242 * to the TR header of the packet, 'h->ts' is the timestamp,
243 * 'h->len' is the length of the packet off the wire, and 'h->caplen'
244 * is the number of bytes actually captured.
245 */
246u_int
247token_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
248{
249	return (token_print(ndo, p, h->len, h->caplen));
250}
251