xref: /freebsd/contrib/tcpdump/print-rip.c (revision a98ff317388a00b992f1bf8404dee596f9383f5e)
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
23 static const char rcsid[] _U_ =
24     "@(#) $Header: /tcpdump/master/tcpdump/print-rip.c,v 1.59 2006-03-23 14:58:44 hannes 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 
40 #include "af.h"
41 
42 struct rip {
43 	u_int8_t rip_cmd;		/* request/response */
44 	u_int8_t rip_vers;		/* protocol version # */
45 	u_int8_t unused[2];		/* unused */
46 };
47 
48 #define	RIPCMD_REQUEST		1	/* want info */
49 #define	RIPCMD_RESPONSE		2	/* responding to request */
50 #define	RIPCMD_TRACEON		3	/* turn tracing on */
51 #define	RIPCMD_TRACEOFF		4	/* turn it off */
52 #define	RIPCMD_POLL		5	/* want info from everybody */
53 #define	RIPCMD_POLLENTRY	6	/* poll for entry */
54 
55 static const struct tok rip_cmd_values[] = {
56     { RIPCMD_REQUEST,	        "Request" },
57     { RIPCMD_RESPONSE,	        "Response" },
58     { RIPCMD_TRACEON,	        "Trace on" },
59     { RIPCMD_TRACEOFF,	        "Trace off" },
60     { RIPCMD_POLL,	        "Poll" },
61     { RIPCMD_POLLENTRY,	        "Poll Entry" },
62     { 0, NULL}
63 };
64 
65 #define RIP_AUTHLEN  16
66 #define RIP_ROUTELEN 20
67 
68 /*
69  * rfc 1723
70  *
71  *  0                   1                   2                   3 3
72  *  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
73  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
74  * | Command (1)   | Version (1)   |           unused              |
75  * +---------------+---------------+-------------------------------+
76  * | Address Family Identifier (2) |        Route Tag (2)          |
77  * +-------------------------------+-------------------------------+
78  * |                         IP Address (4)                        |
79  * +---------------------------------------------------------------+
80  * |                         Subnet Mask (4)                       |
81  * +---------------------------------------------------------------+
82  * |                         Next Hop (4)                          |
83  * +---------------------------------------------------------------+
84  * |                         Metric (4)                            |
85  * +---------------------------------------------------------------+
86  *
87  */
88 
89 struct rip_netinfo {
90 	u_int16_t rip_family;
91 	u_int16_t rip_tag;
92 	u_int32_t rip_dest;
93 	u_int32_t rip_dest_mask;
94 	u_int32_t rip_router;
95 	u_int32_t rip_metric;		/* cost of route */
96 };
97 
98 static void
99 rip_entry_print_v1(register const struct rip_netinfo *ni)
100 {
101 	register u_short family;
102 
103 	/* RFC 1058 */
104 	family = EXTRACT_16BITS(&ni->rip_family);
105 	if (family != BSD_AFNUM_INET && family != 0) {
106 		printf("\n\t AFI %s, ", tok2str(bsd_af_values, "Unknown (%u)", family));
107                 print_unknown_data((u_int8_t *)&ni->rip_family,"\n\t  ",RIP_ROUTELEN);
108 		return;
109 	}
110 	if (EXTRACT_16BITS(&ni->rip_tag) ||
111 	    EXTRACT_32BITS(&ni->rip_dest_mask) ||
112 	    EXTRACT_32BITS(&ni->rip_router)) {
113 		/* MBZ fields not zero */
114                 print_unknown_data((u_int8_t *)&ni->rip_family,"\n\t  ",RIP_ROUTELEN);
115 		return;
116 	}
117 	if (family == 0) {
118 		printf("\n\t  AFI 0, %s, metric: %u",
119 			ipaddr_string(&ni->rip_dest),
120 			EXTRACT_32BITS(&ni->rip_metric));
121 		return;
122 	} /* BSD_AFNUM_INET */
123 	printf("\n\t  %s, metric: %u",
124                ipaddr_string(&ni->rip_dest),
125 	       EXTRACT_32BITS(&ni->rip_metric));
126 }
127 
128 static unsigned
129 rip_entry_print_v2(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 		u_int16_t auth_type = EXTRACT_16BITS(&ni->rip_tag);
136 		if (auth_type == 2) {
137 			register u_char *p = (u_char *)&ni->rip_dest;
138 			u_int i = 0;
139 			printf("\n\t  Simple Text Authentication data: ");
140 			for (; i < RIP_AUTHLEN; p++, i++)
141 				putchar (isprint(*p) ? *p : '.');
142 		} else if (auth_type == 3) {
143 			printf("\n\t  Auth header:");
144 			printf(" Packet Len %u,", EXTRACT_16BITS((u_int8_t *)ni + 4));
145 			printf(" Key-ID %u,", *((u_int8_t *)ni + 6));
146 			printf(" Auth Data Len %u,", *((u_int8_t *)ni + 7));
147 			printf(" SeqNo %u,", EXTRACT_32BITS(&ni->rip_dest_mask));
148 			printf(" MBZ %u,", EXTRACT_32BITS(&ni->rip_router));
149 			printf(" MBZ %u", EXTRACT_32BITS(&ni->rip_metric));
150 		} else if (auth_type == 1) {
151 			printf("\n\t  Auth trailer:");
152 			print_unknown_data((u_int8_t *)&ni->rip_dest,"\n\t  ",remaining);
153 			return remaining; /* AT spans till the packet end */
154                 } else {
155 			printf("\n\t  Unknown (%u) Authentication data:",
156 			       EXTRACT_16BITS(&ni->rip_tag));
157 			print_unknown_data((u_int8_t *)&ni->rip_dest,"\n\t  ",remaining);
158 		}
159 	} else if (family != BSD_AFNUM_INET && family != 0) {
160 		printf("\n\t  AFI %s", tok2str(bsd_af_values, "Unknown (%u)", family));
161                 print_unknown_data((u_int8_t *)&ni->rip_tag,"\n\t  ",RIP_ROUTELEN-2);
162 	} else { /* BSD_AFNUM_INET or AFI 0 */
163 		printf("\n\t  AFI %s, %15s/%-2d, tag 0x%04x, metric: %u, next-hop: ",
164                        tok2str(bsd_af_values, "%u", family),
165                        ipaddr_string(&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 			printf("%s", ipaddr_string(&ni->rip_router));
171                 else
172                     printf("self");
173 	}
174 	return sizeof (*ni);
175 }
176 
177 void
178 rip_print(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 (snapend < dat) {
185 		printf(" [|rip]");
186 		return;
187 	}
188 	i = snapend - dat;
189 	if (i > length)
190 		i = length;
191 	if (i < sizeof(*rp)) {
192 		printf(" [|rip]");
193 		return;
194 	}
195 	i -= sizeof(*rp);
196 
197 	rp = (struct rip *)dat;
198 
199         printf("%sRIPv%u",
200                (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((u_int8_t *)&rp->rip_cmd,"\n\t",length);
217 		break;
218 	default:
219                 /* dump version and lets see if we know the commands name*/
220                 printf(", %s, length: %u",
221                        tok2str(rip_cmd_values,
222                                "unknown command (%u)",
223                                rp->rip_cmd),
224                        length);
225 
226                 if (vflag < 1)
227                     return;
228 
229 		switch (rp->rip_cmd) {
230 		case RIPCMD_REQUEST:
231 		case RIPCMD_RESPONSE:
232 			j = length / sizeof(*ni);
233                         printf(", 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(ni);
239 					i -= sizeof(*ni);
240 				}
241 				else if (rp->rip_vers == 2)
242 					i -= rip_entry_print_v2(ni, i);
243                                 else
244                                     break;
245 			}
246 			if (i)
247 				printf("[|rip]");
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 (vflag <= 1) {
259                         if(!print_unknown_data((u_int8_t *)rp,"\n\t",length))
260                             return;
261                     }
262                     break;
263                 }
264                 /* do we want to see an additionally hexdump ? */
265                 if (vflag> 1) {
266                     if(!print_unknown_data((u_int8_t *)rp,"\n\t",length))
267                         return;
268                 }
269         }
270 }
271 
272 
273