xref: /openbsd/usr.sbin/tcpdump/print-rip.c (revision 73471bf0)
1 /*	$OpenBSD: print-rip.c,v 1.18 2020/01/24 22:46:37 procter Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1990, 1991, 1993, 1994, 1996
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that: (1) source code distributions
9  * retain the above copyright notice and this paragraph in its entirety, (2)
10  * distributions including binary code include the above copyright notice and
11  * this paragraph in its entirety in the documentation or other materials
12  * provided with the distribution, and (3) all advertising materials mentioning
13  * features or use of this software display the following acknowledgement:
14  * ``This product includes software developed by the University of California,
15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16  * the University nor the names of its contributors may be used to endorse
17  * or promote products derived from this software without specific prior
18  * written permission.
19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22  */
23 
24 #include <sys/time.h>
25 #include <sys/socket.h>
26 
27 #include <netinet/in.h>
28 #include <netinet/ip.h>
29 #include <netinet/ip_var.h>
30 #include <netinet/udp.h>
31 #include <netinet/udp_var.h>
32 
33 #include <stdio.h>
34 #include <string.h>
35 #include <ctype.h>
36 
37 #include "interface.h"
38 #include "addrtoname.h"
39 #include "extract.h"			/* must come after interface.h */
40 
41 struct rip {
42 	u_char rip_cmd;			/* request/response */
43 	u_char rip_vers;		/* protocol version # */
44 	u_short rip_zero2;		/* unused */
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 #define RIP_AUTHLEN 16
54 
55 struct rip_netinfo {
56 	u_short rip_family;
57 	u_short rip_tag;
58 	u_int32_t rip_dest;
59 	u_int32_t rip_dest_mask;
60 	u_int32_t rip_router;
61 	u_int32_t rip_metric;		/* cost of route */
62 };
63 
64 static void
65 rip_printblk(const u_char *cp, const u_char *ep)
66 {
67 	for (; cp < ep; cp += 2)
68 		printf(" %04x", EXTRACT_16BITS(cp));
69 	return;
70 }
71 
72 static void
73 rip_entry_print_v1(int vers, const struct rip_netinfo *ni)
74 {
75 	u_short family;
76 
77 	/* RFC 1058 */
78 	family = EXTRACT_16BITS(&ni->rip_family);
79 	if (family != AF_INET) {
80 		printf(" [family %d:", family);
81 		rip_printblk((u_char *)&ni->rip_tag,
82 			     (u_char *)&ni->rip_metric +
83 			     sizeof(ni->rip_metric));
84 		printf("]");
85 		return;
86 	}
87 	if (ni->rip_tag || ni->rip_dest_mask || ni->rip_router) {
88 		/* MBZ fields not zero */
89 		printf(" [");
90 		rip_printblk((u_char *)&ni->rip_family,
91 			     (u_char *)&ni->rip_metric +
92 			     sizeof(ni->rip_metric));
93 		printf("]");
94 		return;
95 	}
96 	printf(" {%s}(%d)", ipaddr_string(&ni->rip_dest),
97 	       EXTRACT_32BITS(&ni->rip_metric));
98 }
99 
100 static void
101 rip_entry_print_v2(int vers, const struct rip_netinfo *ni)
102 {
103 	u_char *p;
104 	u_short family;
105 	char buf[RIP_AUTHLEN];
106 
107 	/* RFC 1723 */
108 	family = EXTRACT_16BITS(&ni->rip_family);
109 	if (family == 0xFFFF) {
110 		if (EXTRACT_16BITS(&ni->rip_tag) == 2) {
111 			memcpy(buf, &ni->rip_dest, sizeof(buf));
112 			buf[sizeof(buf)-1] = '\0';
113 			for (p = buf; *p; p++) {
114 				if (!isprint(*p))
115 					break;
116 			}
117 			if (!*p) {
118 				printf(" [password %s]", buf);
119 			} else {
120 				printf(" [password: ");
121 				rip_printblk((u_char *)&ni->rip_dest,
122 					     (u_char *)&ni->rip_metric +
123 					     sizeof(ni->rip_metric));
124 				printf("]");
125 			}
126 		} else {
127 			printf(" [auth %d:",
128 			       EXTRACT_16BITS(&ni->rip_tag));
129 			rip_printblk((u_char *)&ni->rip_dest,
130 				     (u_char *)&ni->rip_metric +
131 				     sizeof(ni->rip_metric));
132 			printf("]");
133 		}
134 	} else if (family != AF_INET) {
135 		printf(" [family %d:", family);
136 		rip_printblk((u_char *)&ni->rip_tag,
137 			     (u_char *)&ni->rip_metric +
138 			     sizeof(ni->rip_metric));
139 		printf("]");
140 		return;
141 	} else { /* AF_INET */
142 		printf(" {%s", ipaddr_string(&ni->rip_dest));
143 		if (ni->rip_dest_mask)
144 			printf("/%s", ipaddr_string(&ni->rip_dest_mask));
145 		if (ni->rip_router)
146 			printf("->%s", ipaddr_string(&ni->rip_router));
147 		if (ni->rip_tag)
148 			printf(" tag %04x", EXTRACT_16BITS(&ni->rip_tag));
149 		printf("}(%d)", EXTRACT_32BITS(&ni->rip_metric));
150 	}
151 }
152 
153 void
154 rip_print(const u_char *dat, u_int length)
155 {
156 	const struct rip *rp;
157 	const struct rip_netinfo *ni;
158 	int i, j, trunc;
159 
160 	i = min(length, snapend - dat) - sizeof(*rp);
161 	if (i < 0) {
162 		printf("[|rip]");
163 		return;
164 	}
165 
166 	rp = (struct rip *)dat;
167 	switch (rp->rip_vers) {
168 	case 0:
169 		/* RFC 1058 */
170 		printf("RIPv0: ");
171 		rip_printblk((u_char *)(rp + 1), snapend);
172 		break;
173 	default:
174 		switch (rp->rip_cmd) {
175 		case RIPCMD_REQUEST:
176 			printf("RIPv%d-req %d", rp->rip_vers, length);
177 			break;
178 		case RIPCMD_RESPONSE:
179 			j = length / sizeof(*ni);
180 			if (j * sizeof(*ni) != length - 4)
181 				printf("RIPv%d-resp [items %d] [%d]:",
182 				       rp->rip_vers, j, length);
183 			else
184 				printf("RIPv%d-resp [items %d]:",
185 				       rp->rip_vers, j);
186 			trunc = (i / sizeof(*ni)) != j;
187 			ni = (struct rip_netinfo *)(rp + 1);
188 			for (; (i -= sizeof(*ni)) >= 0; ++ni) {
189 				if (rp->rip_vers == 1)
190 					rip_entry_print_v1(rp->rip_vers, ni);
191 				else
192 					rip_entry_print_v2(rp->rip_vers, ni);
193 			}
194 			if (trunc)
195 				printf("[|rip]");
196 			break;
197 		case RIPCMD_TRACEON:
198 			printf("RIPv%d-traceon %d: \"", rp->rip_vers, length);
199 			(void)fn_print((const u_char *)(rp + 1), snapend);
200 			printf("\"");
201 			break;
202 		case RIPCMD_TRACEOFF:
203 			printf("RIPv%d-traceoff %d", rp->rip_vers, length);
204 			break;
205 		case RIPCMD_POLL:
206 			printf("RIPv%d-poll %d", rp->rip_vers, length);
207 			break;
208 		case RIPCMD_POLLENTRY:
209 			printf("RIPv%d-pollentry %d", rp->rip_vers, length);
210 			break;
211 		default:
212 			printf("RIPv%d-#%d %d", rp->rip_vers, rp->rip_cmd,
213 			       length);
214 			break;
215 		}
216         }
217 }
218