print-rip.c revision 251158 
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 * $FreeBSD: head/contrib/tcpdump/print-rip.c 251158 2013-05-30 20:51:22Z delphij $
22 */
23
24#ifndef lint
25static const char rcsid[] _U_ =
26    "@(#) $Header: /tcpdump/master/tcpdump/print-rip.c,v 1.59 2006-03-23 14:58:44 hannes Exp $ (LBL)";
27#endif
28
29#ifdef HAVE_CONFIG_H
30#include "config.h"
31#endif
32
33#include <tcpdump-stdinc.h>
34
35#include <stdio.h>
36#include <string.h>
37
38#include "interface.h"
39#include "addrtoname.h"
40#include "extract.h"			/* must come after interface.h */
41
42#include "af.h"
43
44struct rip {
45	u_int8_t rip_cmd;		/* request/response */
46	u_int8_t rip_vers;		/* protocol version # */
47	u_int8_t unused[2];		/* unused */
48};
49
50#define	RIPCMD_REQUEST		1	/* want info */
51#define	RIPCMD_RESPONSE		2	/* responding to request */
52#define	RIPCMD_TRACEON		3	/* turn tracing on */
53#define	RIPCMD_TRACEOFF		4	/* turn it off */
54#define	RIPCMD_POLL		5	/* want info from everybody */
55#define	RIPCMD_POLLENTRY	6	/* poll for entry */
56
57static const struct tok rip_cmd_values[] = {
58    { RIPCMD_REQUEST,	        "Request" },
59    { RIPCMD_RESPONSE,	        "Response" },
60    { RIPCMD_TRACEON,	        "Trace on" },
61    { RIPCMD_TRACEOFF,	        "Trace off" },
62    { RIPCMD_POLL,	        "Poll" },
63    { RIPCMD_POLLENTRY,	        "Poll Entry" },
64    { 0, NULL}
65};
66
67#define RIP_AUTHLEN  16
68#define RIP_ROUTELEN 20
69
70/*
71 * rfc 1723
72 *
73 *  0                   1                   2                   3 3
74 *  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
75 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
76 * | Command (1)   | Version (1)   |           unused              |
77 * +---------------+---------------+-------------------------------+
78 * | Address Family Identifier (2) |        Route Tag (2)          |
79 * +-------------------------------+-------------------------------+
80 * |                         IP Address (4)                        |
81 * +---------------------------------------------------------------+
82 * |                         Subnet Mask (4)                       |
83 * +---------------------------------------------------------------+
84 * |                         Next Hop (4)                          |
85 * +---------------------------------------------------------------+
86 * |                         Metric (4)                            |
87 * +---------------------------------------------------------------+
88 *
89 */
90
91struct rip_netinfo {
92	u_int16_t rip_family;
93	u_int16_t rip_tag;
94	u_int32_t rip_dest;
95	u_int32_t rip_dest_mask;
96	u_int32_t rip_router;
97	u_int32_t rip_metric;		/* cost of route */
98};
99
100static void
101rip_entry_print_v1(register const struct rip_netinfo *ni)
102{
103	register u_short family;
104
105	/* RFC 1058 */
106	family = EXTRACT_16BITS(&ni->rip_family);
107	if (family != BSD_AFNUM_INET && family != 0) {
108		printf("\n\t AFI %s, ", tok2str(bsd_af_values, "Unknown (%u)", family));
109                print_unknown_data((u_int8_t *)&ni->rip_family,"\n\t  ",RIP_ROUTELEN);
110		return;
111	}
112	if (EXTRACT_16BITS(&ni->rip_tag) ||
113	    EXTRACT_32BITS(&ni->rip_dest_mask) ||
114	    EXTRACT_32BITS(&ni->rip_router)) {
115		/* MBZ fields not zero */
116                print_unknown_data((u_int8_t *)&ni->rip_family,"\n\t  ",RIP_ROUTELEN);
117		return;
118	}
119	if (family == 0) {
120		printf("\n\t  AFI 0, %s, metric: %u",
121			ipaddr_string(&ni->rip_dest),
122			EXTRACT_32BITS(&ni->rip_metric));
123		return;
124	} /* BSD_AFNUM_INET */
125	printf("\n\t  %s, metric: %u",
126               ipaddr_string(&ni->rip_dest),
127	       EXTRACT_32BITS(&ni->rip_metric));
128}
129
130static unsigned
131rip_entry_print_v2(register const struct rip_netinfo *ni, const unsigned remaining)
132{
133	register u_short family;
134
135	family = EXTRACT_16BITS(&ni->rip_family);
136	if (family == 0xFFFF) { /* variable-sized authentication structures */
137		u_int16_t auth_type = EXTRACT_16BITS(&ni->rip_tag);
138		if (auth_type == 2) {
139			register u_char *p = (u_char *)&ni->rip_dest;
140			u_int i = 0;
141			printf("\n\t  Simple Text Authentication data: ");
142			for (; i < RIP_AUTHLEN; p++, i++)
143				putchar (isprint(*p) ? *p : '.');
144		} else if (auth_type == 3) {
145			printf("\n\t  Auth header:");
146			printf(" Packet Len %u,", EXTRACT_16BITS((u_int16_t *)ni + 2));
147			printf(" Key-ID %u,", *((u_int8_t *)ni + 6));
148			printf(" Auth Data Len %u,", *((u_int8_t *)ni + 7));
149			printf(" SeqNo %u,", EXTRACT_32BITS(&ni->rip_dest_mask));
150			printf(" MBZ %u,", EXTRACT_32BITS(&ni->rip_router));
151			printf(" MBZ %u", EXTRACT_32BITS(&ni->rip_metric));
152		} else if (auth_type == 1) {
153			printf("\n\t  Auth trailer:");
154			print_unknown_data((u_int8_t *)&ni->rip_dest,"\n\t  ",remaining);
155			return remaining; /* AT spans till the packet end */
156                } else {
157			printf("\n\t  Unknown (%u) Authentication data:",
158			       EXTRACT_16BITS(&ni->rip_tag));
159			print_unknown_data((u_int8_t *)&ni->rip_dest,"\n\t  ",remaining);
160		}
161	} else if (family != BSD_AFNUM_INET && family != 0) {
162		printf("\n\t  AFI %s", tok2str(bsd_af_values, "Unknown (%u)", family));
163                print_unknown_data((u_int8_t *)&ni->rip_tag,"\n\t  ",RIP_ROUTELEN-2);
164	} else { /* BSD_AFNUM_INET or AFI 0 */
165		printf("\n\t  AFI %s, %15s/%-2d, tag 0x%04x, metric: %u, next-hop: ",
166                       tok2str(bsd_af_values, "%u", family),
167                       ipaddr_string(&ni->rip_dest),
168		       mask2plen(EXTRACT_32BITS(&ni->rip_dest_mask)),
169                       EXTRACT_16BITS(&ni->rip_tag),
170                       EXTRACT_32BITS(&ni->rip_metric));
171		if (EXTRACT_32BITS(&ni->rip_router))
172			printf("%s", ipaddr_string(&ni->rip_router));
173                else
174                    printf("self");
175	}
176	return sizeof (*ni);
177}
178
179void
180rip_print(const u_char *dat, u_int length)
181{
182	register const struct rip *rp;
183	register const struct rip_netinfo *ni;
184	register u_int i, j;
185
186	if (snapend < dat) {
187		printf(" [|rip]");
188		return;
189	}
190	i = snapend - dat;
191	if (i > length)
192		i = length;
193	if (i < sizeof(*rp)) {
194		printf(" [|rip]");
195		return;
196	}
197	i -= sizeof(*rp);
198
199	rp = (struct rip *)dat;
200
201        printf("%sRIPv%u",
202               (vflag >= 1) ? "\n\t" : "",
203               rp->rip_vers);
204
205	switch (rp->rip_vers) {
206	case 0:
207		/*
208		 * RFC 1058.
209		 *
210		 * XXX - RFC 1058 says
211		 *
212		 * 0  Datagrams whose version number is zero are to be ignored.
213		 *    These are from a previous version of the protocol, whose
214		 *    packet format was machine-specific.
215		 *
216		 * so perhaps we should just dump the packet, in hex.
217		 */
218                print_unknown_data((u_int8_t *)&rp->rip_cmd,"\n\t",length);
219		break;
220	default:
221                /* dump version and lets see if we know the commands name*/
222                printf(", %s, length: %u",
223                       tok2str(rip_cmd_values,
224                               "unknown command (%u)",
225                               rp->rip_cmd),
226                       length);
227
228                if (vflag < 1)
229                    return;
230
231		switch (rp->rip_cmd) {
232		case RIPCMD_REQUEST:
233		case RIPCMD_RESPONSE:
234			j = length / sizeof(*ni);
235                        printf(", routes: %u%s", j, rp->rip_vers == 2 ? " or less" : "");
236			ni = (struct rip_netinfo *)(rp + 1);
237			for (; i >= sizeof(*ni); ++ni) {
238				if (rp->rip_vers == 1)
239				{
240					rip_entry_print_v1(ni);
241					i -= sizeof(*ni);
242				}
243				else if (rp->rip_vers == 2)
244					i -= rip_entry_print_v2(ni, i);
245                                else
246                                    break;
247			}
248			if (i)
249				printf("[|rip]");
250			break;
251
252		case RIPCMD_TRACEOFF:
253		case RIPCMD_POLL:
254		case RIPCMD_POLLENTRY:
255			break;
256
257		case RIPCMD_TRACEON:
258                    /* fall through */
259	        default:
260                    if (vflag <= 1) {
261                        if(!print_unknown_data((u_int8_t *)rp,"\n\t",length))
262                            return;
263                    }
264                    break;
265                }
266                /* do we want to see an additionally hexdump ? */
267                if (vflag> 1) {
268                    if(!print_unknown_data((u_int8_t *)rp,"\n\t",length))
269                        return;
270                }
271        }
272}
273
274
275