1 /*
2 * Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996, 1997
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
22 /* \summary: Fiber Distributed Data Interface (FDDI) printer */
23
24 #ifdef HAVE_CONFIG_H
25 #include <config.h>
26 #endif
27
28 #include "netdissect-stdinc.h"
29
30 #include <string.h>
31
32 #include "netdissect.h"
33 #include "extract.h"
34 #include "addrtoname.h"
35
36 /*
37 * Based on Ultrix if_fddi.h
38 */
39
40 struct fddi_header {
41 nd_uint8_t fddi_fc; /* frame control */
42 nd_mac_addr fddi_dhost;
43 nd_mac_addr fddi_shost;
44 };
45
46 /*
47 * Length of an FDDI header; note that some compilers may pad
48 * "struct fddi_header" to a multiple of 4 bytes, for example, so
49 * "sizeof (struct fddi_header)" may not give the right
50 * answer.
51 */
52 #define FDDI_HDRLEN 13
53
54 /* Useful values for fddi_fc (frame control) field */
55
56 /*
57 * FDDI Frame Control bits
58 */
59 #define FDDIFC_C 0x80 /* Class bit */
60 #define FDDIFC_L 0x40 /* Address length bit */
61 #define FDDIFC_F 0x30 /* Frame format bits */
62 #define FDDIFC_Z 0x0f /* Control bits */
63
64 /*
65 * FDDI Frame Control values. (48-bit addressing only).
66 */
67 #define FDDIFC_VOID 0x40 /* Void frame */
68 #define FDDIFC_NRT 0x80 /* Nonrestricted token */
69 #define FDDIFC_RT 0xc0 /* Restricted token */
70 #define FDDIFC_SMT_INFO 0x41 /* SMT Info */
71 #define FDDIFC_SMT_NSA 0x4F /* SMT Next station adrs */
72 #define FDDIFC_MAC_BEACON 0xc2 /* MAC Beacon frame */
73 #define FDDIFC_MAC_CLAIM 0xc3 /* MAC Claim frame */
74 #define FDDIFC_LLC_ASYNC 0x50 /* Async. LLC frame */
75 #define FDDIFC_LLC_SYNC 0xd0 /* Sync. LLC frame */
76 #define FDDIFC_IMP_ASYNC 0x60 /* Implementor Async. */
77 #define FDDIFC_IMP_SYNC 0xe0 /* Implementor Synch. */
78 #define FDDIFC_SMT 0x40 /* SMT frame */
79 #define FDDIFC_MAC 0xc0 /* MAC frame */
80
81 #define FDDIFC_CLFF 0xF0 /* Class/Length/Format bits */
82 #define FDDIFC_ZZZZ 0x0F /* Control bits */
83
84 /*
85 * Some FDDI interfaces use bit-swapped addresses.
86 */
87 #if defined(ultrix) || defined(__alpha) || defined(__bsdi) || defined(__NetBSD__) || defined(__linux__)
88 static int fddi_bitswap = 0;
89 #else
90 static int fddi_bitswap = 1;
91 #endif
92
93 /*
94 * FDDI support for tcpdump, by Jeffrey Mogul [DECWRL], June 1992
95 *
96 * Based in part on code by Van Jacobson, which bears this note:
97 *
98 * NOTE: This is a very preliminary hack for FDDI support.
99 * There are all sorts of wired in constants & nothing (yet)
100 * to print SMT packets as anything other than hex dumps.
101 * Most of the necessary changes are waiting on my redoing
102 * the "header" that a kernel fddi driver supplies to bpf: I
103 * want it to look like one byte of 'direction' (0 or 1
104 * depending on whether the packet was inbound or outbound),
105 * two bytes of system/driver dependent data (anything an
106 * implementor thinks would be useful to filter on and/or
107 * save per-packet, then the real 21-byte FDDI header.
108 * Steve McCanne & I have also talked about adding the
109 * 'direction' byte to all bpf headers (e.g., in the two
110 * bytes of padding on an ethernet header). It's not clear
111 * we could do this in a backwards compatible way & we hate
112 * the idea of an incompatible bpf change. Discussions are
113 * proceeding.
114 *
115 * Also, to really support FDDI (and better support 802.2
116 * over ethernet) we really need to re-think the rather simple
117 * minded assumptions about fixed length & fixed format link
118 * level headers made in gencode.c. One day...
119 *
120 * - vj
121 */
122
123 static const u_char fddi_bit_swap[] = {
124 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
125 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
126 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
127 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
128 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
129 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
130 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
131 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
132 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
133 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
134 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
135 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
136 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
137 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
138 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
139 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
140 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
141 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
142 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
143 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
144 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
145 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
146 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
147 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
148 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
149 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
150 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
151 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
152 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
153 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
154 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
155 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff,
156 };
157
158 /*
159 * Print FDDI frame-control bits
160 */
161 static void
print_fddi_fc(netdissect_options * ndo,u_char fc)162 print_fddi_fc(netdissect_options *ndo, u_char fc)
163 {
164 switch (fc) {
165
166 case FDDIFC_VOID: /* Void frame */
167 ND_PRINT("void ");
168 break;
169
170 case FDDIFC_NRT: /* Nonrestricted token */
171 ND_PRINT("nrt ");
172 break;
173
174 case FDDIFC_RT: /* Restricted token */
175 ND_PRINT("rt ");
176 break;
177
178 case FDDIFC_SMT_INFO: /* SMT Info */
179 ND_PRINT("info ");
180 break;
181
182 case FDDIFC_SMT_NSA: /* SMT Next station adrs */
183 ND_PRINT("nsa ");
184 break;
185
186 case FDDIFC_MAC_BEACON: /* MAC Beacon frame */
187 ND_PRINT("beacon ");
188 break;
189
190 case FDDIFC_MAC_CLAIM: /* MAC Claim frame */
191 ND_PRINT("claim ");
192 break;
193
194 default:
195 switch (fc & FDDIFC_CLFF) {
196
197 case FDDIFC_MAC:
198 ND_PRINT("mac%1x ", fc & FDDIFC_ZZZZ);
199 break;
200
201 case FDDIFC_SMT:
202 ND_PRINT("smt%1x ", fc & FDDIFC_ZZZZ);
203 break;
204
205 case FDDIFC_LLC_ASYNC:
206 ND_PRINT("async%1x ", fc & FDDIFC_ZZZZ);
207 break;
208
209 case FDDIFC_LLC_SYNC:
210 ND_PRINT("sync%1x ", fc & FDDIFC_ZZZZ);
211 break;
212
213 case FDDIFC_IMP_ASYNC:
214 ND_PRINT("imp_async%1x ", fc & FDDIFC_ZZZZ);
215 break;
216
217 case FDDIFC_IMP_SYNC:
218 ND_PRINT("imp_sync%1x ", fc & FDDIFC_ZZZZ);
219 break;
220
221 default:
222 ND_PRINT("%02x ", fc);
223 break;
224 }
225 }
226 }
227
228 /* Extract src, dst addresses */
229 static void
extract_fddi_addrs(const struct fddi_header * fddip,char * fsrc,char * fdst)230 extract_fddi_addrs(const struct fddi_header *fddip, char *fsrc, char *fdst)
231 {
232 int i;
233
234 if (fddi_bitswap) {
235 /*
236 * bit-swap the fddi addresses (isn't the IEEE standards
237 * process wonderful!) then convert them to names.
238 */
239 for (i = 0; i < 6; ++i)
240 fdst[i] = fddi_bit_swap[fddip->fddi_dhost[i]];
241 for (i = 0; i < 6; ++i)
242 fsrc[i] = fddi_bit_swap[fddip->fddi_shost[i]];
243 }
244 else {
245 memcpy(fdst, (const char *)fddip->fddi_dhost, 6);
246 memcpy(fsrc, (const char *)fddip->fddi_shost, 6);
247 }
248 }
249
250 /*
251 * Print the FDDI MAC header
252 */
253 static void
fddi_hdr_print(netdissect_options * ndo,const struct fddi_header * fddip,u_int length,const u_char * fsrc,const u_char * fdst)254 fddi_hdr_print(netdissect_options *ndo,
255 const struct fddi_header *fddip, u_int length,
256 const u_char *fsrc, const u_char *fdst)
257 {
258 const char *srcname, *dstname;
259
260 srcname = etheraddr_string(ndo, fsrc);
261 dstname = etheraddr_string(ndo, fdst);
262
263 if (!ndo->ndo_qflag)
264 print_fddi_fc(ndo, GET_U_1(fddip->fddi_fc));
265 ND_PRINT("%s > %s, length %u: ",
266 srcname, dstname,
267 length);
268 }
269
270 static void
fddi_smt_print(netdissect_options * ndo,const u_char * p _U_,u_int length _U_)271 fddi_smt_print(netdissect_options *ndo, const u_char *p _U_, u_int length _U_)
272 {
273 ND_PRINT("<SMT printer not yet implemented>");
274 }
275
276 u_int
fddi_print(netdissect_options * ndo,const u_char * p,u_int length,u_int caplen)277 fddi_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
278 {
279 const struct fddi_header *fddip = (const struct fddi_header *)p;
280 uint8_t fc;
281 nd_mac_addr srcmac, dstmac;
282 struct lladdr_info src, dst;
283 int llc_hdrlen;
284
285 ndo->ndo_protocol = "fddi";
286 if (caplen < FDDI_HDRLEN) {
287 nd_print_trunc(ndo);
288 return (caplen);
289 }
290
291 fc = GET_U_1(fddip->fddi_fc);
292
293 /*
294 * Get the FDDI addresses into a canonical form
295 */
296 extract_fddi_addrs(fddip, (char *)srcmac, (char *)dstmac);
297
298 if (ndo->ndo_eflag)
299 fddi_hdr_print(ndo, fddip, length, srcmac, dstmac);
300
301 src.addr = srcmac;
302 src.addr_string = etheraddr_string;
303 dst.addr = dstmac;
304 dst.addr_string = etheraddr_string;
305
306 /* Skip over FDDI MAC header */
307 length -= FDDI_HDRLEN;
308 p += FDDI_HDRLEN;
309 caplen -= FDDI_HDRLEN;
310
311 /* Frame Control field determines interpretation of packet */
312 if ((fc & FDDIFC_CLFF) == FDDIFC_LLC_ASYNC) {
313 /* Try to print the LLC-layer header & higher layers */
314 llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
315 if (llc_hdrlen < 0) {
316 /*
317 * Some kinds of LLC packet we cannot
318 * handle intelligently
319 */
320 if (!ndo->ndo_suppress_default_print)
321 ND_DEFAULTPRINT(p, caplen);
322 llc_hdrlen = -llc_hdrlen;
323 }
324 } else if ((fc & FDDIFC_CLFF) == FDDIFC_SMT) {
325 fddi_smt_print(ndo, p, caplen);
326 llc_hdrlen = 0;
327 } else {
328 /* Some kinds of FDDI packet we cannot handle intelligently */
329 if (!ndo->ndo_eflag)
330 fddi_hdr_print(ndo, fddip, length + FDDI_HDRLEN, srcmac,
331 dstmac);
332 if (!ndo->ndo_suppress_default_print)
333 ND_DEFAULTPRINT(p, caplen);
334 llc_hdrlen = 0;
335 }
336 return (FDDI_HDRLEN + llc_hdrlen);
337 }
338
339 /*
340 * This is the top level routine of the printer. 'p' points
341 * to the FDDI header of the packet, 'h->ts' is the timestamp,
342 * 'h->len' is the length of the packet off the wire, and 'h->caplen'
343 * is the number of bytes actually captured.
344 */
345 void
fddi_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h,const u_char * p)346 fddi_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
347 {
348 ndo->ndo_protocol = "fddi";
349 ndo->ndo_ll_hdr_len += fddi_print(ndo, p, h->len, h->caplen);
350 }
351