xref: /freebsd/contrib/tcpdump/print-rip.c (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
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 1.57 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 
40 struct 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 
53 static 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 
87 struct 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 
96 static void
97 rip_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 
120 static void
121 rip_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 
159 void
160 rip_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