1/*
2 * Copyright (c) 1989, 1990, 1991, 1993, 1994, 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
22#define NETDISSECT_REWORKED
23#ifdef HAVE_CONFIG_H
24#include "config.h"
25#endif
26
27#include <tcpdump-stdinc.h>
28
29#include <stdio.h>
30
31#include "interface.h"
32#include "addrtoname.h"
33#include "extract.h"			/* must come after interface.h */
34
35#include "af.h"
36
37static const char tstr[] = "[|rip]";
38
39struct rip {
40	uint8_t rip_cmd;		/* request/response */
41	uint8_t rip_vers;		/* protocol version # */
42	uint8_t unused[2];		/* unused */
43};
44
45#define	RIPCMD_REQUEST		1	/* want info */
46#define	RIPCMD_RESPONSE		2	/* responding to request */
47#define	RIPCMD_TRACEON		3	/* turn tracing on */
48#define	RIPCMD_TRACEOFF		4	/* turn it off */
49#define	RIPCMD_POLL		5	/* want info from everybody */
50#define	RIPCMD_POLLENTRY	6	/* poll for entry */
51
52static const struct tok rip_cmd_values[] = {
53    { RIPCMD_REQUEST,	        "Request" },
54    { RIPCMD_RESPONSE,	        "Response" },
55    { RIPCMD_TRACEON,	        "Trace on" },
56    { RIPCMD_TRACEOFF,	        "Trace off" },
57    { RIPCMD_POLL,	        "Poll" },
58    { RIPCMD_POLLENTRY,	        "Poll Entry" },
59    { 0, NULL}
60};
61
62#define RIP_AUTHLEN  16
63#define RIP_ROUTELEN 20
64
65/*
66 * rfc 1723
67 *
68 *  0                   1                   2                   3 3
69 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
70 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
71 * | Command (1)   | Version (1)   |           unused              |
72 * +---------------+---------------+-------------------------------+
73 * | Address Family Identifier (2) |        Route Tag (2)          |
74 * +-------------------------------+-------------------------------+
75 * |                         IP Address (4)                        |
76 * +---------------------------------------------------------------+
77 * |                         Subnet Mask (4)                       |
78 * +---------------------------------------------------------------+
79 * |                         Next Hop (4)                          |
80 * +---------------------------------------------------------------+
81 * |                         Metric (4)                            |
82 * +---------------------------------------------------------------+
83 *
84 */
85
86struct rip_netinfo {
87	uint16_t rip_family;
88	uint16_t rip_tag;
89	uint32_t rip_dest;
90	uint32_t rip_dest_mask;
91	uint32_t rip_router;
92	uint32_t rip_metric;		/* cost of route */
93};
94
95static void
96rip_entry_print_v1(netdissect_options *ndo,
97                   register const struct rip_netinfo *ni)
98{
99	register u_short family;
100
101	/* RFC 1058 */
102	family = EXTRACT_16BITS(&ni->rip_family);
103	if (family != BSD_AFNUM_INET && family != 0) {
104		ND_PRINT((ndo, "\n\t AFI %s, ", tok2str(bsd_af_values, "Unknown (%u)", family)));
105		print_unknown_data(ndo, (uint8_t *)&ni->rip_family, "\n\t  ", RIP_ROUTELEN);
106		return;
107	}
108	if (EXTRACT_16BITS(&ni->rip_tag) ||
109	    EXTRACT_32BITS(&ni->rip_dest_mask) ||
110	    EXTRACT_32BITS(&ni->rip_router)) {
111		/* MBZ fields not zero */
112                print_unknown_data(ndo, (uint8_t *)&ni->rip_family, "\n\t  ", RIP_ROUTELEN);
113		return;
114	}
115	if (family == 0) {
116		ND_PRINT((ndo, "\n\t  AFI 0, %s, metric: %u",
117			ipaddr_string(ndo, &ni->rip_dest),
118			EXTRACT_32BITS(&ni->rip_metric)));
119		return;
120	} /* BSD_AFNUM_INET */
121	ND_PRINT((ndo, "\n\t  %s, metric: %u",
122               ipaddr_string(ndo, &ni->rip_dest),
123	       EXTRACT_32BITS(&ni->rip_metric)));
124}
125
126static unsigned
127rip_entry_print_v2(netdissect_options *ndo,
128                   register const struct rip_netinfo *ni, const unsigned remaining)
129{
130	register u_short family;
131
132	family = EXTRACT_16BITS(&ni->rip_family);
133	if (family == 0xFFFF) { /* variable-sized authentication structures */
134		uint16_t auth_type = EXTRACT_16BITS(&ni->rip_tag);
135		if (auth_type == 2) {
136			register u_char *p = (u_char *)&ni->rip_dest;
137			u_int i = 0;
138			ND_PRINT((ndo, "\n\t  Simple Text Authentication data: "));
139			for (; i < RIP_AUTHLEN; p++, i++)
140				ND_PRINT((ndo, "%c", ND_ISPRINT(*p) ? *p : '.'));
141		} else if (auth_type == 3) {
142			ND_PRINT((ndo, "\n\t  Auth header:"));
143			ND_PRINT((ndo, " Packet Len %u,", EXTRACT_16BITS((uint8_t *)ni + 4)));
144			ND_PRINT((ndo, " Key-ID %u,", *((uint8_t *)ni + 6)));
145			ND_PRINT((ndo, " Auth Data Len %u,", *((uint8_t *)ni + 7)));
146			ND_PRINT((ndo, " SeqNo %u,", EXTRACT_32BITS(&ni->rip_dest_mask)));
147			ND_PRINT((ndo, " MBZ %u,", EXTRACT_32BITS(&ni->rip_router)));
148			ND_PRINT((ndo, " MBZ %u", EXTRACT_32BITS(&ni->rip_metric)));
149		} else if (auth_type == 1) {
150			ND_PRINT((ndo, "\n\t  Auth trailer:"));
151			print_unknown_data(ndo, (uint8_t *)&ni->rip_dest, "\n\t  ", remaining);
152			return remaining; /* AT spans till the packet end */
153		} else {
154			ND_PRINT((ndo, "\n\t  Unknown (%u) Authentication data:",
155			       EXTRACT_16BITS(&ni->rip_tag)));
156			print_unknown_data(ndo, (uint8_t *)&ni->rip_dest, "\n\t  ", remaining);
157		}
158	} else if (family != BSD_AFNUM_INET && family != 0) {
159		ND_PRINT((ndo, "\n\t  AFI %s", tok2str(bsd_af_values, "Unknown (%u)", family)));
160                print_unknown_data(ndo, (uint8_t *)&ni->rip_tag, "\n\t  ", RIP_ROUTELEN-2);
161	} else { /* BSD_AFNUM_INET or AFI 0 */
162		ND_PRINT((ndo, "\n\t  AFI %s, %15s/%-2d, tag 0x%04x, metric: %u, next-hop: ",
163                       tok2str(bsd_af_values, "%u", family),
164                       ipaddr_string(ndo, &ni->rip_dest),
165		       mask2plen(EXTRACT_32BITS(&ni->rip_dest_mask)),
166                       EXTRACT_16BITS(&ni->rip_tag),
167                       EXTRACT_32BITS(&ni->rip_metric)));
168		if (EXTRACT_32BITS(&ni->rip_router))
169			ND_PRINT((ndo, "%s", ipaddr_string(ndo, &ni->rip_router)));
170		else
171			ND_PRINT((ndo, "self"));
172	}
173	return sizeof (*ni);
174}
175
176void
177rip_print(netdissect_options *ndo,
178          const u_char *dat, u_int length)
179{
180	register const struct rip *rp;
181	register const struct rip_netinfo *ni;
182	register u_int i, j;
183
184	if (ndo->ndo_snapend < dat) {
185		ND_PRINT((ndo, " %s", tstr));
186		return;
187	}
188	i = ndo->ndo_snapend - dat;
189	if (i > length)
190		i = length;
191	if (i < sizeof(*rp)) {
192		ND_PRINT((ndo, " %s", tstr));
193		return;
194	}
195	i -= sizeof(*rp);
196
197	rp = (struct rip *)dat;
198
199	ND_PRINT((ndo, "%sRIPv%u",
200               (ndo->ndo_vflag >= 1) ? "\n\t" : "",
201               rp->rip_vers));
202
203	switch (rp->rip_vers) {
204	case 0:
205		/*
206		 * RFC 1058.
207		 *
208		 * XXX - RFC 1058 says
209		 *
210		 * 0  Datagrams whose version number is zero are to be ignored.
211		 *    These are from a previous version of the protocol, whose
212		 *    packet format was machine-specific.
213		 *
214		 * so perhaps we should just dump the packet, in hex.
215		 */
216                print_unknown_data(ndo, (uint8_t *)&rp->rip_cmd, "\n\t", length);
217		break;
218	default:
219                /* dump version and lets see if we know the commands name*/
220                ND_PRINT((ndo, ", %s, length: %u",
221                       tok2str(rip_cmd_values,
222                               "unknown command (%u)",
223                               rp->rip_cmd),
224                       length));
225
226                if (ndo->ndo_vflag < 1)
227                    return;
228
229		switch (rp->rip_cmd) {
230		case RIPCMD_REQUEST:
231		case RIPCMD_RESPONSE:
232			j = length / sizeof(*ni);
233			ND_PRINT((ndo, ", routes: %u%s", j, rp->rip_vers == 2 ? " or less" : ""));
234			ni = (struct rip_netinfo *)(rp + 1);
235			for (; i >= sizeof(*ni); ++ni) {
236				if (rp->rip_vers == 1)
237				{
238					rip_entry_print_v1(ndo, ni);
239					i -= sizeof(*ni);
240				}
241				else if (rp->rip_vers == 2)
242					i -= rip_entry_print_v2(ndo, ni, i);
243                                else
244                                    break;
245			}
246			if (i)
247				ND_PRINT((ndo, "%s", tstr));
248			break;
249
250		case RIPCMD_TRACEOFF:
251		case RIPCMD_POLL:
252		case RIPCMD_POLLENTRY:
253			break;
254
255		case RIPCMD_TRACEON:
256                    /* fall through */
257	        default:
258                    if (ndo->ndo_vflag <= 1) {
259                        if(!print_unknown_data(ndo, (uint8_t *)rp, "\n\t", length))
260                            return;
261                    }
262                    break;
263                }
264                /* do we want to see an additionally hexdump ? */
265                if (ndo->ndo_vflag> 1) {
266                    if(!print_unknown_data(ndo, (uint8_t *)rp, "\n\t", length))
267                        return;
268                }
269        }
270}
271
272
273