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 #ifndef lint
27 static const char rcsid[] _U_ =
28     "@(#) $Header: /tcpdump/master/tcpdump/print-token.c,v 1.27 2005-11-13 12:12:43 guy Exp $";
29 #endif
30 
31 #ifdef HAVE_CONFIG_H
32 #include "config.h"
33 #endif
34 
35 #include <tcpdump-stdinc.h>
36 
37 #include <pcap.h>
38 #include <stdio.h>
39 #include <string.h>
40 
41 #include "interface.h"
42 #include "extract.h"
43 #include "addrtoname.h"
44 #include "ethertype.h"
45 
46 #include "ether.h"
47 #include "token.h"
48 
49 /* Extract src, dst addresses */
50 static inline void
extract_token_addrs(const struct token_header * trp,char * fsrc,char * fdst)51 extract_token_addrs(const struct token_header *trp, char *fsrc, char *fdst)
52 {
53 	memcpy(fdst, (const char *)trp->token_dhost, 6);
54 	memcpy(fsrc, (const char *)trp->token_shost, 6);
55 }
56 
57 /*
58  * Print the TR MAC header
59  */
60 static inline void
token_hdr_print(register const struct token_header * trp,register u_int length,register const u_char * fsrc,register const u_char * fdst)61 token_hdr_print(register const struct token_header *trp, register u_int length,
62 	   register const u_char *fsrc, register const u_char *fdst)
63 {
64 	const char *srcname, *dstname;
65 
66 	srcname = etheraddr_string(fsrc);
67 	dstname = etheraddr_string(fdst);
68 
69 	if (vflag)
70 		(void) printf("%02x %02x %s %s %d: ",
71 		       trp->token_ac,
72 		       trp->token_fc,
73 		       srcname, dstname,
74 		       length);
75 	else
76 		printf("%s %s %d: ", srcname, dstname, length);
77 }
78 
79 static const char *broadcast_indicator[] = {
80 	"Non-Broadcast", "Non-Broadcast",
81 	"Non-Broadcast", "Non-Broadcast",
82 	"All-routes",    "All-routes",
83 	"Single-route",  "Single-route"
84 };
85 
86 static const char *direction[] = {
87 	"Forward", "Backward"
88 };
89 
90 static const char *largest_frame[] = {
91 	"516",
92 	"1500",
93 	"2052",
94 	"4472",
95 	"8144",
96 	"11407",
97 	"17800",
98 	"??"
99 };
100 
101 u_int
token_print(const u_char * p,u_int length,u_int caplen)102 token_print(const u_char *p, u_int length, u_int caplen)
103 {
104 	const struct token_header *trp;
105 	u_short extracted_ethertype;
106 	struct ether_header ehdr;
107 	u_int route_len = 0, hdr_len = TOKEN_HDRLEN;
108 	int seg;
109 
110 	trp = (const struct token_header *)p;
111 
112 	if (caplen < TOKEN_HDRLEN) {
113 		printf("[|token-ring]");
114 		return hdr_len;
115 	}
116 
117 	/*
118 	 * Get the TR addresses into a canonical form
119 	 */
120 	extract_token_addrs(trp, (char*)ESRC(&ehdr), (char*)EDST(&ehdr));
121 
122 	/* Adjust for source routing information in the MAC header */
123 	if (IS_SOURCE_ROUTED(trp)) {
124 		/* Clear source-routed bit */
125 		*ESRC(&ehdr) &= 0x7f;
126 
127 		if (eflag)
128 			token_hdr_print(trp, length, ESRC(&ehdr), EDST(&ehdr));
129 
130 		if (caplen < TOKEN_HDRLEN + 2) {
131 			printf("[|token-ring]");
132 			return hdr_len;
133 		}
134 		route_len = RIF_LENGTH(trp);
135 		hdr_len += route_len;
136 		if (caplen < hdr_len) {
137 			printf("[|token-ring]");
138 			return hdr_len;
139 		}
140 		if (vflag) {
141 			printf("%s ", broadcast_indicator[BROADCAST(trp)]);
142 			printf("%s", direction[DIRECTION(trp)]);
143 
144 			for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
145 				printf(" [%d:%d]", RING_NUMBER(trp, seg),
146 				    BRIDGE_NUMBER(trp, seg));
147 		} else {
148 			printf("rt = %x", EXTRACT_16BITS(&trp->token_rcf));
149 
150 			for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
151 				printf(":%x", EXTRACT_16BITS(&trp->token_rseg[seg]));
152 		}
153 		printf(" (%s) ", largest_frame[LARGEST_FRAME(trp)]);
154 	} else {
155 		if (eflag)
156 			token_hdr_print(trp, length, ESRC(&ehdr), EDST(&ehdr));
157 	}
158 
159 	/* Skip over token ring MAC header and routing information */
160 	length -= hdr_len;
161 	p += hdr_len;
162 	caplen -= hdr_len;
163 
164 	/* Frame Control field determines interpretation of packet */
165 	if (FRAME_TYPE(trp) == TOKEN_FC_LLC) {
166 		/* Try to print the LLC-layer header & higher layers */
167 		if (llc_print(p, length, caplen, ESRC(&ehdr), EDST(&ehdr),
168 		    &extracted_ethertype) == 0) {
169 			/* ether_type not known, print raw packet */
170 			if (!eflag)
171 				token_hdr_print(trp,
172 				    length + TOKEN_HDRLEN + route_len,
173 				    ESRC(&ehdr), EDST(&ehdr));
174 			if (extracted_ethertype) {
175 				printf("(LLC %s) ",
176 			etherproto_string(htons(extracted_ethertype)));
177 			}
178 			if (!suppress_default_print)
179 				default_print(p, caplen);
180 		}
181 	} else {
182 		/* Some kinds of TR packet we cannot handle intelligently */
183 		/* XXX - dissect MAC packets if frame type is 0 */
184 		if (!eflag)
185 			token_hdr_print(trp, length + TOKEN_HDRLEN + route_len,
186 			    ESRC(&ehdr), EDST(&ehdr));
187 		if (!suppress_default_print)
188 			default_print(p, caplen);
189 	}
190 	return (hdr_len);
191 }
192 
193 /*
194  * This is the top level routine of the printer.  'p' points
195  * to the TR header of the packet, 'h->ts' is the timestamp,
196  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
197  * is the number of bytes actually captured.
198  */
199 u_int
token_if_print(const struct pcap_pkthdr * h,const u_char * p)200 token_if_print(const struct pcap_pkthdr *h, const u_char *p)
201 {
202 	return (token_print(p, h->len, h->caplen));
203 }
204