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/* \summary: Routing Information Protocol (RIP) printer */
23
24#ifdef HAVE_CONFIG_H
25#include "config.h"
26#endif
27
28#include <netdissect-stdinc.h>
29
30#include <stdio.h>
31
32#include "netdissect.h"
33#include "addrtoname.h"
34#include "extract.h"
35
36#include "af.h"
37
38static const char tstr[] = "[|rip]";
39
40struct rip {
41	uint8_t rip_cmd;		/* request/response */
42	uint8_t rip_vers;		/* protocol version # */
43	uint8_t unused[2];		/* unused */
44};
45
46#define	RIPCMD_REQUEST		1	/* want info */
47#define	RIPCMD_RESPONSE		2	/* responding to request */
48#define	RIPCMD_TRACEON		3	/* turn tracing on */
49#define	RIPCMD_TRACEOFF		4	/* turn it off */
50#define	RIPCMD_POLL		5	/* want info from everybody */
51#define	RIPCMD_POLLENTRY	6	/* poll for entry */
52
53static const struct tok rip_cmd_values[] = {
54    { RIPCMD_REQUEST,	        "Request" },
55    { RIPCMD_RESPONSE,	        "Response" },
56    { RIPCMD_TRACEON,	        "Trace on" },
57    { RIPCMD_TRACEOFF,	        "Trace off" },
58    { RIPCMD_POLL,	        "Poll" },
59    { RIPCMD_POLLENTRY,	        "Poll Entry" },
60    { 0, NULL}
61};
62
63#define RIP_AUTHLEN  16
64#define RIP_ROUTELEN 20
65
66/*
67 * rfc 1723
68 *
69 *  0                   1                   2                   3 3
70 *  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
71 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
72 * | Command (1)   | Version (1)   |           unused              |
73 * +---------------+---------------+-------------------------------+
74 * | Address Family Identifier (2) |        Route Tag (2)          |
75 * +-------------------------------+-------------------------------+
76 * |                         IP Address (4)                        |
77 * +---------------------------------------------------------------+
78 * |                         Subnet Mask (4)                       |
79 * +---------------------------------------------------------------+
80 * |                         Next Hop (4)                          |
81 * +---------------------------------------------------------------+
82 * |                         Metric (4)                            |
83 * +---------------------------------------------------------------+
84 *
85 */
86
87struct rip_netinfo {
88	uint16_t rip_family;
89	uint16_t rip_tag;
90	uint32_t rip_dest;
91	uint32_t rip_dest_mask;
92	uint32_t rip_router;
93	uint32_t rip_metric;		/* cost of route */
94};
95
96static void
97rip_entry_print_v1(netdissect_options *ndo,
98                   register const struct rip_netinfo *ni)
99{
100	register u_short family;
101
102	/* RFC 1058 */
103	family = EXTRACT_16BITS(&ni->rip_family);
104	if (family != BSD_AFNUM_INET && family != 0) {
105		ND_PRINT((ndo, "\n\t AFI %s, ", tok2str(bsd_af_values, "Unknown (%u)", family)));
106		print_unknown_data(ndo, (const uint8_t *)&ni->rip_family, "\n\t  ", RIP_ROUTELEN);
107		return;
108	}
109	if (EXTRACT_16BITS(&ni->rip_tag) ||
110	    EXTRACT_32BITS(&ni->rip_dest_mask) ||
111	    EXTRACT_32BITS(&ni->rip_router)) {
112		/* MBZ fields not zero */
113                print_unknown_data(ndo, (const uint8_t *)&ni->rip_family, "\n\t  ", RIP_ROUTELEN);
114		return;
115	}
116	if (family == 0) {
117		ND_PRINT((ndo, "\n\t  AFI 0, %s, metric: %u",
118			ipaddr_string(ndo, &ni->rip_dest),
119			EXTRACT_32BITS(&ni->rip_metric)));
120		return;
121	} /* BSD_AFNUM_INET */
122	ND_PRINT((ndo, "\n\t  %s, metric: %u",
123               ipaddr_string(ndo, &ni->rip_dest),
124	       EXTRACT_32BITS(&ni->rip_metric)));
125}
126
127static unsigned
128rip_entry_print_v2(netdissect_options *ndo,
129                   register const struct rip_netinfo *ni, const unsigned remaining)
130{
131	register u_short family;
132
133	family = EXTRACT_16BITS(&ni->rip_family);
134	if (family == 0xFFFF) { /* variable-sized authentication structures */
135		uint16_t auth_type = EXTRACT_16BITS(&ni->rip_tag);
136		if (auth_type == 2) {
137			register const u_char *p = (const u_char *)&ni->rip_dest;
138			u_int i = 0;
139			ND_PRINT((ndo, "\n\t  Simple Text Authentication data: "));
140			for (; i < RIP_AUTHLEN; p++, i++)
141				ND_PRINT((ndo, "%c", ND_ISPRINT(*p) ? *p : '.'));
142		} else if (auth_type == 3) {
143			ND_PRINT((ndo, "\n\t  Auth header:"));
144			ND_PRINT((ndo, " Packet Len %u,", EXTRACT_16BITS((const uint8_t *)ni + 4)));
145			ND_PRINT((ndo, " Key-ID %u,", *((const uint8_t *)ni + 6)));
146			ND_PRINT((ndo, " Auth Data Len %u,", *((const uint8_t *)ni + 7)));
147			ND_PRINT((ndo, " SeqNo %u,", EXTRACT_32BITS(&ni->rip_dest_mask)));
148			ND_PRINT((ndo, " MBZ %u,", EXTRACT_32BITS(&ni->rip_router)));
149			ND_PRINT((ndo, " MBZ %u", EXTRACT_32BITS(&ni->rip_metric)));
150		} else if (auth_type == 1) {
151			ND_PRINT((ndo, "\n\t  Auth trailer:"));
152			print_unknown_data(ndo, (const uint8_t *)&ni->rip_dest, "\n\t  ", remaining);
153			return remaining; /* AT spans till the packet end */
154		} else {
155			ND_PRINT((ndo, "\n\t  Unknown (%u) Authentication data:",
156			       EXTRACT_16BITS(&ni->rip_tag)));
157			print_unknown_data(ndo, (const uint8_t *)&ni->rip_dest, "\n\t  ", remaining);
158		}
159	} else if (family != BSD_AFNUM_INET && family != 0) {
160		ND_PRINT((ndo, "\n\t  AFI %s", tok2str(bsd_af_values, "Unknown (%u)", family)));
161                print_unknown_data(ndo, (const uint8_t *)&ni->rip_tag, "\n\t  ", RIP_ROUTELEN-2);
162	} else { /* BSD_AFNUM_INET or AFI 0 */
163		ND_PRINT((ndo, "\n\t  AFI %s, %15s/%-2d, tag 0x%04x, metric: %u, next-hop: ",
164                       tok2str(bsd_af_values, "%u", family),
165                       ipaddr_string(ndo, &ni->rip_dest),
166		       mask2plen(EXTRACT_32BITS(&ni->rip_dest_mask)),
167                       EXTRACT_16BITS(&ni->rip_tag),
168                       EXTRACT_32BITS(&ni->rip_metric)));
169		if (EXTRACT_32BITS(&ni->rip_router))
170			ND_PRINT((ndo, "%s", ipaddr_string(ndo, &ni->rip_router)));
171		else
172			ND_PRINT((ndo, "self"));
173	}
174	return sizeof (*ni);
175}
176
177void
178rip_print(netdissect_options *ndo,
179          const u_char *dat, u_int length)
180{
181	register const struct rip *rp;
182	register const struct rip_netinfo *ni;
183	register u_int i, j;
184
185	if (ndo->ndo_snapend < dat) {
186		ND_PRINT((ndo, " %s", tstr));
187		return;
188	}
189	i = ndo->ndo_snapend - dat;
190	if (i > length)
191		i = length;
192	if (i < sizeof(*rp)) {
193		ND_PRINT((ndo, " %s", tstr));
194		return;
195	}
196	i -= sizeof(*rp);
197
198	rp = (const struct rip *)dat;
199
200	ND_PRINT((ndo, "%sRIPv%u",
201               (ndo->ndo_vflag >= 1) ? "\n\t" : "",
202               rp->rip_vers));
203
204	switch (rp->rip_vers) {
205	case 0:
206		/*
207		 * RFC 1058.
208		 *
209		 * XXX - RFC 1058 says
210		 *
211		 * 0  Datagrams whose version number is zero are to be ignored.
212		 *    These are from a previous version of the protocol, whose
213		 *    packet format was machine-specific.
214		 *
215		 * so perhaps we should just dump the packet, in hex.
216		 */
217                print_unknown_data(ndo, (const uint8_t *)&rp->rip_cmd, "\n\t", length);
218		break;
219	default:
220                /* dump version and lets see if we know the commands name*/
221                ND_PRINT((ndo, ", %s, length: %u",
222                       tok2str(rip_cmd_values,
223                               "unknown command (%u)",
224                               rp->rip_cmd),
225                       length));
226
227                if (ndo->ndo_vflag < 1)
228                    return;
229
230		switch (rp->rip_cmd) {
231		case RIPCMD_REQUEST:
232		case RIPCMD_RESPONSE:
233			j = length / sizeof(*ni);
234			ND_PRINT((ndo, ", routes: %u%s", j, rp->rip_vers == 2 ? " or less" : ""));
235			ni = (const struct rip_netinfo *)(rp + 1);
236			for (; i >= sizeof(*ni); ++ni) {
237				if (rp->rip_vers == 1)
238				{
239					rip_entry_print_v1(ndo, ni);
240					i -= sizeof(*ni);
241				}
242				else if (rp->rip_vers == 2)
243					i -= rip_entry_print_v2(ndo, ni, i);
244                                else
245                                    break;
246			}
247			if (i)
248				ND_PRINT((ndo, "%s", tstr));
249			break;
250
251		case RIPCMD_TRACEOFF:
252		case RIPCMD_POLL:
253		case RIPCMD_POLLENTRY:
254			break;
255
256		case RIPCMD_TRACEON:
257                    /* fall through */
258	        default:
259                    if (ndo->ndo_vflag <= 1) {
260                        if(!print_unknown_data(ndo, (const uint8_t *)rp, "\n\t", length))
261                            return;
262                    }
263                    break;
264                }
265                /* do we want to see an additionally hexdump ? */
266                if (ndo->ndo_vflag> 1) {
267                    if(!print_unknown_data(ndo, (const uint8_t *)rp, "\n\t", length))
268                        return;
269                }
270        }
271}
272
273
274