1 /*
2 * Copyright (c) 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 are permitted
6 * provided that the above copyright notice and this paragraph are
7 * duplicated in all such forms and that any documentation,
8 * advertising materials, and other materials related to such
9 * distribution and use acknowledge that the software was developed
10 * by the University of California, Lawrence Berkeley Laboratory,
11 * Berkeley, CA. The name of the University may not be used to
12 * endorse or promote products derived from this software without
13 * specific prior written permission.
14 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
17 *
18 * Initial contribution from Jeff Honig (jch@MITCHELL.CIT.CORNELL.EDU).
19 */
20
21 #define NETDISSECT_REWORKED
22 #ifdef HAVE_CONFIG_H
23 #include "config.h"
24 #endif
25
26 #include <tcpdump-stdinc.h>
27
28 #include "interface.h"
29 #include "addrtoname.h"
30 #include "extract.h"
31
32 struct egp_packet {
33 uint8_t egp_version;
34 #define EGP_VERSION 2
35 uint8_t egp_type;
36 #define EGPT_ACQUIRE 3
37 #define EGPT_REACH 5
38 #define EGPT_POLL 2
39 #define EGPT_UPDATE 1
40 #define EGPT_ERROR 8
41 uint8_t egp_code;
42 #define EGPC_REQUEST 0
43 #define EGPC_CONFIRM 1
44 #define EGPC_REFUSE 2
45 #define EGPC_CEASE 3
46 #define EGPC_CEASEACK 4
47 #define EGPC_HELLO 0
48 #define EGPC_HEARDU 1
49 uint8_t egp_status;
50 #define EGPS_UNSPEC 0
51 #define EGPS_ACTIVE 1
52 #define EGPS_PASSIVE 2
53 #define EGPS_NORES 3
54 #define EGPS_ADMIN 4
55 #define EGPS_GODOWN 5
56 #define EGPS_PARAM 6
57 #define EGPS_PROTO 7
58 #define EGPS_INDET 0
59 #define EGPS_UP 1
60 #define EGPS_DOWN 2
61 #define EGPS_UNSOL 0x80
62 uint16_t egp_checksum;
63 uint16_t egp_as;
64 uint16_t egp_sequence;
65 union {
66 uint16_t egpu_hello;
67 uint8_t egpu_gws[2];
68 uint16_t egpu_reason;
69 #define EGPR_UNSPEC 0
70 #define EGPR_BADHEAD 1
71 #define EGPR_BADDATA 2
72 #define EGPR_NOREACH 3
73 #define EGPR_XSPOLL 4
74 #define EGPR_NORESP 5
75 #define EGPR_UVERSION 6
76 } egp_handg;
77 #define egp_hello egp_handg.egpu_hello
78 #define egp_intgw egp_handg.egpu_gws[0]
79 #define egp_extgw egp_handg.egpu_gws[1]
80 #define egp_reason egp_handg.egpu_reason
81 union {
82 uint16_t egpu_poll;
83 uint32_t egpu_sourcenet;
84 } egp_pands;
85 #define egp_poll egp_pands.egpu_poll
86 #define egp_sourcenet egp_pands.egpu_sourcenet
87 };
88
89 static const char *egp_acquire_codes[] = {
90 "request",
91 "confirm",
92 "refuse",
93 "cease",
94 "cease_ack"
95 };
96
97 static const char *egp_acquire_status[] = {
98 "unspecified",
99 "active_mode",
100 "passive_mode",
101 "insufficient_resources",
102 "administratively_prohibited",
103 "going_down",
104 "parameter_violation",
105 "protocol_violation"
106 };
107
108 static const char *egp_reach_codes[] = {
109 "hello",
110 "i-h-u"
111 };
112
113 static const char *egp_status_updown[] = {
114 "indeterminate",
115 "up",
116 "down"
117 };
118
119 static const char *egp_reasons[] = {
120 "unspecified",
121 "bad_EGP_header_format",
122 "bad_EGP_data_field_format",
123 "reachability_info_unavailable",
124 "excessive_polling_rate",
125 "no_response",
126 "unsupported_version"
127 };
128
129 static void
egpnrprint(netdissect_options * ndo,register const struct egp_packet * egp)130 egpnrprint(netdissect_options *ndo,
131 register const struct egp_packet *egp)
132 {
133 register const uint8_t *cp;
134 uint32_t addr;
135 register uint32_t net;
136 register u_int netlen;
137 int gateways, distances, networks;
138 int t_gateways;
139 const char *comma;
140
141 addr = egp->egp_sourcenet;
142 if (IN_CLASSA(addr)) {
143 net = addr & IN_CLASSA_NET;
144 netlen = 1;
145 } else if (IN_CLASSB(addr)) {
146 net = addr & IN_CLASSB_NET;
147 netlen = 2;
148 } else if (IN_CLASSC(addr)) {
149 net = addr & IN_CLASSC_NET;
150 netlen = 3;
151 } else {
152 net = 0;
153 netlen = 0;
154 }
155 cp = (uint8_t *)(egp + 1);
156
157 t_gateways = egp->egp_intgw + egp->egp_extgw;
158 for (gateways = 0; gateways < t_gateways; ++gateways) {
159 /* Pickup host part of gateway address */
160 addr = 0;
161 ND_TCHECK2(cp[0], 4 - netlen);
162 switch (netlen) {
163
164 case 1:
165 addr = *cp++;
166 /* fall through */
167 case 2:
168 addr = (addr << 8) | *cp++;
169 /* fall through */
170 case 3:
171 addr = (addr << 8) | *cp++;
172 }
173 addr |= net;
174 ND_TCHECK2(cp[0], 1);
175 distances = *cp++;
176 ND_PRINT((ndo, " %s %s ",
177 gateways < (int)egp->egp_intgw ? "int" : "ext",
178 ipaddr_string(ndo, &addr)));
179
180 comma = "";
181 ND_PRINT((ndo, "("));
182 while (--distances >= 0) {
183 ND_TCHECK2(cp[0], 2);
184 ND_PRINT((ndo, "%sd%d:", comma, (int)*cp++));
185 comma = ", ";
186 networks = *cp++;
187 while (--networks >= 0) {
188 /* Pickup network number */
189 ND_TCHECK2(cp[0], 1);
190 addr = (uint32_t)*cp++ << 24;
191 if (IN_CLASSB(addr)) {
192 ND_TCHECK2(cp[0], 1);
193 addr |= (uint32_t)*cp++ << 16;
194 } else if (!IN_CLASSA(addr)) {
195 ND_TCHECK2(cp[0], 2);
196 addr |= (uint32_t)*cp++ << 16;
197 addr |= (uint32_t)*cp++ << 8;
198 }
199 ND_PRINT((ndo, " %s", ipaddr_string(ndo, &addr)));
200 }
201 }
202 ND_PRINT((ndo, ")"));
203 }
204 return;
205 trunc:
206 ND_PRINT((ndo, "[|]"));
207 }
208
209 void
egp_print(netdissect_options * ndo,register const uint8_t * bp,register u_int length)210 egp_print(netdissect_options *ndo,
211 register const uint8_t *bp, register u_int length)
212 {
213 register const struct egp_packet *egp;
214 register int status;
215 register int code;
216 register int type;
217
218 egp = (struct egp_packet *)bp;
219 if (!ND_TTEST2(*egp, length)) {
220 ND_PRINT((ndo, "[|egp]"));
221 return;
222 }
223
224 if (!ndo->ndo_vflag) {
225 ND_PRINT((ndo, "EGPv%u, AS %u, seq %u, length %u",
226 egp->egp_version,
227 EXTRACT_16BITS(&egp->egp_as),
228 EXTRACT_16BITS(&egp->egp_sequence),
229 length));
230 return;
231 } else
232 ND_PRINT((ndo, "EGPv%u, length %u",
233 egp->egp_version,
234 length));
235
236 if (egp->egp_version != EGP_VERSION) {
237 ND_PRINT((ndo, "[version %d]", egp->egp_version));
238 return;
239 }
240
241 type = egp->egp_type;
242 code = egp->egp_code;
243 status = egp->egp_status;
244
245 switch (type) {
246 case EGPT_ACQUIRE:
247 ND_PRINT((ndo, " acquire"));
248 switch (code) {
249 case EGPC_REQUEST:
250 case EGPC_CONFIRM:
251 ND_PRINT((ndo, " %s", egp_acquire_codes[code]));
252 switch (status) {
253 case EGPS_UNSPEC:
254 case EGPS_ACTIVE:
255 case EGPS_PASSIVE:
256 ND_PRINT((ndo, " %s", egp_acquire_status[status]));
257 break;
258
259 default:
260 ND_PRINT((ndo, " [status %d]", status));
261 break;
262 }
263 ND_PRINT((ndo, " hello:%d poll:%d",
264 EXTRACT_16BITS(&egp->egp_hello),
265 EXTRACT_16BITS(&egp->egp_poll)));
266 break;
267
268 case EGPC_REFUSE:
269 case EGPC_CEASE:
270 case EGPC_CEASEACK:
271 ND_PRINT((ndo, " %s", egp_acquire_codes[code]));
272 switch (status ) {
273 case EGPS_UNSPEC:
274 case EGPS_NORES:
275 case EGPS_ADMIN:
276 case EGPS_GODOWN:
277 case EGPS_PARAM:
278 case EGPS_PROTO:
279 ND_PRINT((ndo, " %s", egp_acquire_status[status]));
280 break;
281
282 default:
283 ND_PRINT((ndo, "[status %d]", status));
284 break;
285 }
286 break;
287
288 default:
289 ND_PRINT((ndo, "[code %d]", code));
290 break;
291 }
292 break;
293
294 case EGPT_REACH:
295 switch (code) {
296
297 case EGPC_HELLO:
298 case EGPC_HEARDU:
299 ND_PRINT((ndo, " %s", egp_reach_codes[code]));
300 if (status <= EGPS_DOWN)
301 ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
302 else
303 ND_PRINT((ndo, " [status %d]", status));
304 break;
305
306 default:
307 ND_PRINT((ndo, "[reach code %d]", code));
308 break;
309 }
310 break;
311
312 case EGPT_POLL:
313 ND_PRINT((ndo, " poll"));
314 if (egp->egp_status <= EGPS_DOWN)
315 ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
316 else
317 ND_PRINT((ndo, " [status %d]", status));
318 ND_PRINT((ndo, " net:%s", ipaddr_string(ndo, &egp->egp_sourcenet)));
319 break;
320
321 case EGPT_UPDATE:
322 ND_PRINT((ndo, " update"));
323 if (status & EGPS_UNSOL) {
324 status &= ~EGPS_UNSOL;
325 ND_PRINT((ndo, " unsolicited"));
326 }
327 if (status <= EGPS_DOWN)
328 ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
329 else
330 ND_PRINT((ndo, " [status %d]", status));
331 ND_PRINT((ndo, " %s int %d ext %d",
332 ipaddr_string(ndo, &egp->egp_sourcenet),
333 egp->egp_intgw,
334 egp->egp_extgw));
335 if (ndo->ndo_vflag)
336 egpnrprint(ndo, egp);
337 break;
338
339 case EGPT_ERROR:
340 ND_PRINT((ndo, " error"));
341 if (status <= EGPS_DOWN)
342 ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
343 else
344 ND_PRINT((ndo, " [status %d]", status));
345
346 if (EXTRACT_16BITS(&egp->egp_reason) <= EGPR_UVERSION)
347 ND_PRINT((ndo, " %s", egp_reasons[EXTRACT_16BITS(&egp->egp_reason)]));
348 else
349 ND_PRINT((ndo, " [reason %d]", EXTRACT_16BITS(&egp->egp_reason)));
350 break;
351
352 default:
353 ND_PRINT((ndo, "[type %d]", type));
354 break;
355 }
356 }
357