print-rip.c revision 146774 
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#ifndef lint
23static const char rcsid[] _U_ =
24    "@(#) $Header: /tcpdump/master/tcpdump/print-rip.c,v 1.57 2003/11/16 09:36:34 guy Exp $ (LBL)";
25#endif
26
27#ifdef HAVE_CONFIG_H
28#include "config.h"
29#endif
30
31#include <tcpdump-stdinc.h>
32
33#include <stdio.h>
34#include <string.h>
35
36#include "interface.h"
37#include "addrtoname.h"
38#include "extract.h"			/* must come after interface.h */
39
40struct rip {
41	u_int8_t rip_cmd;		/* request/response */
42	u_int8_t rip_vers;		/* protocol version # */
43	u_int8_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	u_int16_t rip_family;
89	u_int16_t rip_tag;
90	u_int32_t rip_dest;
91	u_int32_t rip_dest_mask;
92	u_int32_t rip_router;
93	u_int32_t rip_metric;		/* cost of route */
94};
95
96static void
97rip_entry_print_v1(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 != AF_INET) {
104		printf("\n\t AFI: %u:", family);
105                print_unknown_data((u_int8_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((u_int8_t *)&ni->rip_family,"\n\t  ",RIP_ROUTELEN);
113		return;
114	} /* AF_INET */
115	printf("\n\t  %s, metric: %u",
116               ipaddr_string(&ni->rip_dest),
117	       EXTRACT_32BITS(&ni->rip_metric));
118}
119
120static void
121rip_entry_print_v2(register const struct rip_netinfo *ni)
122{
123	register u_char *p;
124	register u_short family;
125	u_char buf[RIP_AUTHLEN];
126
127	family = EXTRACT_16BITS(&ni->rip_family);
128	if (family == 0xFFFF) { /* 16 bytes authentication ? */
129                if (EXTRACT_16BITS(&ni->rip_tag) == 2) { /* simple text authentication ? */
130			memcpy(buf, &ni->rip_dest, sizeof(buf));
131			buf[sizeof(buf)-1] = '\0';
132			for (p = buf; *p; p++) {
133				if (!isprint(*p))
134					break;
135			}
136                        printf("\n\t  Simple Text Authentication data: %s", buf);
137                } else {
138			printf("\n\t  Unknown (%u) Authentication data:",
139			       EXTRACT_16BITS(&ni->rip_tag));
140                        print_unknown_data((u_int8_t *)&ni->rip_dest,"\n\t  ",RIP_AUTHLEN);
141		}
142	} else if (family != AF_INET) {
143		printf("\n\t  AFI: %u", family);
144                print_unknown_data((u_int8_t *)&ni->rip_tag,"\n\t  ",RIP_ROUTELEN-2);
145		return;
146	} else { /* AF_INET */
147		printf("\n\t  AFI: IPv4: %15s/%-2d, tag 0x%04x, metric: %u, next-hop: ",
148                       ipaddr_string(&ni->rip_dest),
149		       mask2plen(EXTRACT_32BITS(&ni->rip_dest_mask)),
150                       EXTRACT_16BITS(&ni->rip_tag),
151                       EXTRACT_32BITS(&ni->rip_metric));
152		if (EXTRACT_32BITS(&ni->rip_router))
153			printf("%s", ipaddr_string(&ni->rip_router));
154                else
155                    printf("self");
156	}
157}
158
159void
160rip_print(const u_char *dat, u_int length)
161{
162	register const struct rip *rp;
163	register const struct rip_netinfo *ni;
164	register u_int i, j;
165	register int trunc;
166
167	if (snapend < dat) {
168		printf(" [|rip]");
169		return;
170	}
171	i = snapend - dat;
172	if (i > length)
173		i = length;
174	if (i < sizeof(*rp)) {
175		printf(" [|rip]");
176		return;
177	}
178	i -= sizeof(*rp);
179
180	rp = (struct rip *)dat;
181
182        printf("%sRIPv%u",
183               (vflag >= 1) ? "\n\t" : "",
184               rp->rip_vers);
185
186	switch (rp->rip_vers) {
187	case 0:
188		/*
189		 * RFC 1058.
190		 *
191		 * XXX - RFC 1058 says
192		 *
193		 * 0  Datagrams whose version number is zero are to be ignored.
194		 *    These are from a previous version of the protocol, whose
195		 *    packet format was machine-specific.
196		 *
197		 * so perhaps we should just dump the packet, in hex.
198		 */
199                print_unknown_data((u_int8_t *)&rp->rip_cmd,"\n\t",length);
200		break;
201	default:
202                /* dump version and lets see if we know the commands name*/
203                printf(", %s, length: %u",
204                       tok2str(rip_cmd_values,
205                               "unknown command (%u)",
206                               rp->rip_cmd),
207                       length);
208
209                if (vflag < 1)
210                    return;
211
212		switch (rp->rip_cmd) {
213		case RIPCMD_RESPONSE:
214			j = length / sizeof(*ni);
215                        printf(", routes: %u",j);
216			trunc = (i / sizeof(*ni)) != j;
217			ni = (struct rip_netinfo *)(rp + 1);
218			for (; i >= sizeof(*ni); ++ni) {
219				if (rp->rip_vers == 1)
220					rip_entry_print_v1(ni);
221				else if (rp->rip_vers == 2)
222					rip_entry_print_v2(ni);
223                                else
224                                    break;
225				i -= sizeof(*ni);
226			}
227			if (trunc)
228				printf("[|rip]");
229			break;
230
231		case RIPCMD_REQUEST:
232		case RIPCMD_TRACEOFF:
233		case RIPCMD_POLL:
234		case RIPCMD_POLLENTRY:
235			break;
236
237		case RIPCMD_TRACEON:
238                    /* fall through */
239	        default:
240                    if (vflag <= 1) {
241                        if(!print_unknown_data((u_int8_t *)rp,"\n\t",length))
242                            return;
243                    }
244                    break;
245                }
246                /* do we want to see an additionally hexdump ? */
247                if (vflag> 1) {
248                    if(!print_unknown_data((u_int8_t *)rp,"\n\t",length))
249                        return;
250                }
251        }
252}
253
254
255