xref: /freebsd/contrib/tcpdump/print-token.c (revision 55141f2c8991b2a6adbf30bb0fe3e6cbc303f06d)
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 /* \summary: Token Ring printer */
28 
29 #ifdef HAVE_CONFIG_H
30 #include <config.h>
31 #endif
32 
33 #include "netdissect-stdinc.h"
34 
35 #include <string.h>
36 
37 #include "netdissect.h"
38 #include "extract.h"
39 #include "addrtoname.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 ROUTING_SEGMENT_MAX	16
71 #define IS_SOURCE_ROUTED(trp)	((trp)->token_shost[0] & 0x80)
72 #define FRAME_TYPE(trp)		((GET_U_1((trp)->token_fc) & 0xC0) >> 6)
73 #define TOKEN_FC_LLC		1
74 
75 #define BROADCAST(trp)		((GET_BE_U_2((trp)->token_rcf) & 0xE000) >> 13)
76 #define RIF_LENGTH(trp)		((GET_BE_U_2((trp)->token_rcf) & 0x1f00) >> 8)
77 #define DIRECTION(trp)		((GET_BE_U_2((trp)->token_rcf) & 0x0080) >> 7)
78 #define LARGEST_FRAME(trp)	((GET_BE_U_2((trp)->token_rcf) & 0x0070) >> 4)
79 #define RING_NUMBER(trp, x)	((GET_BE_U_2((trp)->token_rseg[x]) & 0xfff0) >> 4)
80 #define BRIDGE_NUMBER(trp, x)	(GET_BE_U_2((trp)->token_rseg[x]) & 0x000f)
81 #define SEGMENT_COUNT(trp)	((int)((RIF_LENGTH(trp) - 2) / 2))
82 
83 struct token_header {
84 	nd_uint8_t   token_ac;
85 	nd_uint8_t   token_fc;
86 	nd_mac_addr  token_dhost;
87 	nd_mac_addr  token_shost;
88 	nd_uint16_t  token_rcf;
89 	nd_uint16_t  token_rseg[ROUTING_SEGMENT_MAX];
90 };
91 
92 
93 /* Extract src, dst addresses */
94 static void
95 extract_token_addrs(const struct token_header *trp, char *fsrc, char *fdst)
96 {
97 	memcpy(fdst, (const char *)trp->token_dhost, 6);
98 	memcpy(fsrc, (const char *)trp->token_shost, 6);
99 }
100 
101 /*
102  * Print the TR MAC header
103  */
104 static void
105 token_hdr_print(netdissect_options *ndo,
106                 const struct token_header *trp, u_int length,
107                 const u_char *fsrc, const u_char *fdst)
108 {
109 	const char *srcname, *dstname;
110 
111 	srcname = etheraddr_string(ndo, fsrc);
112 	dstname = etheraddr_string(ndo, fdst);
113 
114 	if (!ndo->ndo_qflag)
115 		ND_PRINT("%02x %02x ",
116 		       GET_U_1(trp->token_ac),
117 		       GET_U_1(trp->token_fc));
118 	ND_PRINT("%s > %s, length %u: ",
119 	       srcname, dstname,
120 	       length);
121 }
122 
123 static const char *broadcast_indicator[] = {
124 	"Non-Broadcast", "Non-Broadcast",
125 	"Non-Broadcast", "Non-Broadcast",
126 	"All-routes",    "All-routes",
127 	"Single-route",  "Single-route"
128 };
129 
130 static const char *direction[] = {
131 	"Forward", "Backward"
132 };
133 
134 static const char *largest_frame[] = {
135 	"516",
136 	"1500",
137 	"2052",
138 	"4472",
139 	"8144",
140 	"11407",
141 	"17800",
142 	"??"
143 };
144 
145 u_int
146 token_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
147 {
148 	const struct token_header *trp;
149 	int llc_hdrlen;
150 	nd_mac_addr srcmac, dstmac;
151 	struct lladdr_info src, dst;
152 	u_int route_len = 0, hdr_len = TOKEN_HDRLEN;
153 	int seg;
154 
155 	ndo->ndo_protocol = "token-ring";
156 	trp = (const struct token_header *)p;
157 
158 	if (caplen < TOKEN_HDRLEN) {
159 		nd_print_trunc(ndo);
160 		return hdr_len;
161 	}
162 
163 	/*
164 	 * Get the TR addresses into a canonical form
165 	 */
166 	extract_token_addrs(trp, (char*)srcmac, (char*)dstmac);
167 
168 	/* Adjust for source routing information in the MAC header */
169 	if (IS_SOURCE_ROUTED(trp)) {
170 		/* Clear source-routed bit */
171 		srcmac[0] &= 0x7f;
172 
173 		if (ndo->ndo_eflag)
174 			token_hdr_print(ndo, trp, length, srcmac, dstmac);
175 
176 		if (caplen < TOKEN_HDRLEN + 2) {
177 			nd_print_trunc(ndo);
178 			return hdr_len;
179 		}
180 		route_len = RIF_LENGTH(trp);
181 		hdr_len += route_len;
182 		if (caplen < hdr_len) {
183 			nd_print_trunc(ndo);
184 			return hdr_len;
185 		}
186 		if (ndo->ndo_vflag) {
187 			ND_PRINT("%s ", broadcast_indicator[BROADCAST(trp)]);
188 			ND_PRINT("%s", direction[DIRECTION(trp)]);
189 
190 			for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
191 				ND_PRINT(" [%u:%u]", RING_NUMBER(trp, seg),
192 				    BRIDGE_NUMBER(trp, seg));
193 		} else {
194 			ND_PRINT("rt = %x", GET_BE_U_2(trp->token_rcf));
195 
196 			for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
197 				ND_PRINT(":%x",
198 					 GET_BE_U_2(trp->token_rseg[seg]));
199 		}
200 		ND_PRINT(" (%s) ", largest_frame[LARGEST_FRAME(trp)]);
201 	} else {
202 		if (ndo->ndo_eflag)
203 			token_hdr_print(ndo, trp, length, srcmac, dstmac);
204 	}
205 
206 	src.addr = srcmac;
207 	src.addr_string = etheraddr_string;
208 	dst.addr = dstmac;
209 	dst.addr_string = etheraddr_string;
210 
211 	/* Skip over token ring MAC header and routing information */
212 	length -= hdr_len;
213 	p += hdr_len;
214 	caplen -= hdr_len;
215 
216 	/* Frame Control field determines interpretation of packet */
217 	if (FRAME_TYPE(trp) == TOKEN_FC_LLC) {
218 		/* Try to print the LLC-layer header & higher layers */
219 		llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
220 		if (llc_hdrlen < 0) {
221 			/* packet type not known, print raw packet */
222 			if (!ndo->ndo_suppress_default_print)
223 				ND_DEFAULTPRINT(p, caplen);
224 			llc_hdrlen = -llc_hdrlen;
225 		}
226 		hdr_len += llc_hdrlen;
227 	} else {
228 		/* Some kinds of TR packet we cannot handle intelligently */
229 		/* XXX - dissect MAC packets if frame type is 0 */
230 		if (!ndo->ndo_eflag)
231 			token_hdr_print(ndo, trp, length + TOKEN_HDRLEN + route_len,
232 			    srcmac, dstmac);
233 		if (!ndo->ndo_suppress_default_print)
234 			ND_DEFAULTPRINT(p, caplen);
235 	}
236 	return (hdr_len);
237 }
238 
239 /*
240  * This is the top level routine of the printer.  'p' points
241  * to the TR header of the packet, 'h->ts' is the timestamp,
242  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
243  * is the number of bytes actually captured.
244  */
245 void
246 token_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
247 {
248 	ndo->ndo_protocol = "token-ring";
249 	ndo->ndo_ll_hdr_len += token_print(ndo, p, h->len, h->caplen);
250 }
251