xref: /freebsd/contrib/tcpdump/print-token.c (revision b64c5a0ace59af62eff52bfe110a521dc73c937b)
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 #include <config.h>
30 
31 #include "netdissect-stdinc.h"
32 
33 #include <string.h>
34 
35 #include "netdissect.h"
36 #include "extract.h"
37 #include "addrtoname.h"
38 
39 /*
40  * Copyright (c) 1998, Larry Lile
41  * All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice unmodified, this list of conditions, and the following
48  *    disclaimer.
49  * 2. Redistributions in binary form must reproduce the above copyright
50  *    notice, this list of conditions and the following disclaimer in the
51  *    documentation and/or other materials provided with the distribution.
52  *
53  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63  * SUCH DAMAGE.
64  *
65  */
66 
67 #define TOKEN_HDRLEN		14
68 #define ROUTING_SEGMENT_MAX	16
69 #define IS_SOURCE_ROUTED(trp)	((trp)->token_shost[0] & 0x80)
70 #define FRAME_TYPE(trp)		((GET_U_1((trp)->token_fc) & 0xC0) >> 6)
71 #define TOKEN_FC_LLC		1
72 
73 #define BROADCAST(trp)		((GET_BE_U_2((trp)->token_rcf) & 0xE000) >> 13)
74 #define RIF_LENGTH(trp)		((GET_BE_U_2((trp)->token_rcf) & 0x1f00) >> 8)
75 #define DIRECTION(trp)		((GET_BE_U_2((trp)->token_rcf) & 0x0080) >> 7)
76 #define LARGEST_FRAME(trp)	((GET_BE_U_2((trp)->token_rcf) & 0x0070) >> 4)
77 #define RING_NUMBER(trp, x)	((GET_BE_U_2((trp)->token_rseg[x]) & 0xfff0) >> 4)
78 #define BRIDGE_NUMBER(trp, x)	(GET_BE_U_2((trp)->token_rseg[x]) & 0x000f)
79 #define SEGMENT_COUNT(trp)	((int)((RIF_LENGTH(trp) - 2) / 2))
80 
81 struct token_header {
82 	nd_uint8_t   token_ac;
83 	nd_uint8_t   token_fc;
84 	nd_mac_addr  token_dhost;
85 	nd_mac_addr  token_shost;
86 	nd_uint16_t  token_rcf;
87 	nd_uint16_t  token_rseg[ROUTING_SEGMENT_MAX];
88 };
89 
90 
91 /* Extract src, dst addresses */
92 static void
93 extract_token_addrs(const struct token_header *trp, char *fsrc, char *fdst)
94 {
95 	memcpy(fdst, (const char *)trp->token_dhost, 6);
96 	memcpy(fsrc, (const char *)trp->token_shost, 6);
97 }
98 
99 /*
100  * Print the TR MAC header
101  */
102 static void
103 token_hdr_print(netdissect_options *ndo,
104                 const struct token_header *trp, u_int length,
105                 const u_char *fsrc, const u_char *fdst)
106 {
107 	const char *srcname, *dstname;
108 
109 	srcname = etheraddr_string(ndo, fsrc);
110 	dstname = etheraddr_string(ndo, fdst);
111 
112 	if (!ndo->ndo_qflag)
113 		ND_PRINT("%02x %02x ",
114 		       GET_U_1(trp->token_ac),
115 		       GET_U_1(trp->token_fc));
116 	ND_PRINT("%s > %s, length %u: ",
117 	       srcname, dstname,
118 	       length);
119 }
120 
121 static const char *broadcast_indicator[] = {
122 	"Non-Broadcast", "Non-Broadcast",
123 	"Non-Broadcast", "Non-Broadcast",
124 	"All-routes",    "All-routes",
125 	"Single-route",  "Single-route"
126 };
127 
128 static const char *direction[] = {
129 	"Forward", "Backward"
130 };
131 
132 static const char *largest_frame[] = {
133 	"516",
134 	"1500",
135 	"2052",
136 	"4472",
137 	"8144",
138 	"11407",
139 	"17800",
140 	"??"
141 };
142 
143 u_int
144 token_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
145 {
146 	const struct token_header *trp;
147 	int llc_hdrlen;
148 	nd_mac_addr srcmac, dstmac;
149 	struct lladdr_info src, dst;
150 	u_int route_len = 0, hdr_len = TOKEN_HDRLEN;
151 	int seg;
152 
153 	ndo->ndo_protocol = "token-ring";
154 	trp = (const struct token_header *)p;
155 
156 	if (caplen < TOKEN_HDRLEN) {
157 		nd_print_trunc(ndo);
158 		return hdr_len;
159 	}
160 
161 	/*
162 	 * Get the TR addresses into a canonical form
163 	 */
164 	extract_token_addrs(trp, (char*)srcmac, (char*)dstmac);
165 
166 	/* Adjust for source routing information in the MAC header */
167 	if (IS_SOURCE_ROUTED(trp)) {
168 		/* Clear source-routed bit */
169 		srcmac[0] &= 0x7f;
170 
171 		if (ndo->ndo_eflag)
172 			token_hdr_print(ndo, trp, length, srcmac, dstmac);
173 
174 		if (caplen < TOKEN_HDRLEN + 2) {
175 			nd_print_trunc(ndo);
176 			return hdr_len;
177 		}
178 		route_len = RIF_LENGTH(trp);
179 		hdr_len += route_len;
180 		if (caplen < hdr_len) {
181 			nd_print_trunc(ndo);
182 			return hdr_len;
183 		}
184 		if (ndo->ndo_vflag) {
185 			ND_PRINT("%s ", broadcast_indicator[BROADCAST(trp)]);
186 			ND_PRINT("%s", direction[DIRECTION(trp)]);
187 
188 			for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
189 				ND_PRINT(" [%u:%u]", RING_NUMBER(trp, seg),
190 				    BRIDGE_NUMBER(trp, seg));
191 		} else {
192 			ND_PRINT("rt = %x", GET_BE_U_2(trp->token_rcf));
193 
194 			for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
195 				ND_PRINT(":%x",
196 					 GET_BE_U_2(trp->token_rseg[seg]));
197 		}
198 		ND_PRINT(" (%s) ", largest_frame[LARGEST_FRAME(trp)]);
199 	} else {
200 		if (ndo->ndo_eflag)
201 			token_hdr_print(ndo, trp, length, srcmac, dstmac);
202 	}
203 
204 	src.addr = srcmac;
205 	src.addr_string = etheraddr_string;
206 	dst.addr = dstmac;
207 	dst.addr_string = etheraddr_string;
208 
209 	/* Skip over token ring MAC header and routing information */
210 	length -= hdr_len;
211 	p += hdr_len;
212 	caplen -= hdr_len;
213 
214 	/* Frame Control field determines interpretation of packet */
215 	if (FRAME_TYPE(trp) == TOKEN_FC_LLC) {
216 		/* Try to print the LLC-layer header & higher layers */
217 		llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
218 		if (llc_hdrlen < 0) {
219 			/* packet type not known, print raw packet */
220 			if (!ndo->ndo_suppress_default_print)
221 				ND_DEFAULTPRINT(p, caplen);
222 			llc_hdrlen = -llc_hdrlen;
223 		}
224 		hdr_len += llc_hdrlen;
225 	} else {
226 		/* Some kinds of TR packet we cannot handle intelligently */
227 		/* XXX - dissect MAC packets if frame type is 0 */
228 		if (!ndo->ndo_eflag)
229 			token_hdr_print(ndo, trp, length + TOKEN_HDRLEN + route_len,
230 			    srcmac, dstmac);
231 		if (!ndo->ndo_suppress_default_print)
232 			ND_DEFAULTPRINT(p, caplen);
233 	}
234 	return (hdr_len);
235 }
236 
237 /*
238  * This is the top level routine of the printer.  'p' points
239  * to the TR header of the packet, 'h->ts' is the timestamp,
240  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
241  * is the number of bytes actually captured.
242  */
243 void
244 token_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
245 {
246 	ndo->ndo_protocol = "token-ring";
247 	ndo->ndo_ll_hdr_len += token_print(ndo, p, h->len, h->caplen);
248 }
249