print-rip.c revision 1.2.14.1 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 #include <sys/cdefs.h>
23 #ifndef lint
24 __RCSID("$NetBSD: print-rip.c,v 1.2.14.1 2017/02/19 07:35:24 snj Exp $");
25 #endif
26
27 /* \summary: Routing Information Protocol (RIP) printer */
28
29 #ifdef HAVE_CONFIG_H
30 #include "config.h"
31 #endif
32
33 #include <netdissect-stdinc.h>
34
35 #include <stdio.h>
36
37 #include "netdissect.h"
38 #include "addrtoname.h"
39 #include "extract.h"
40
41 #include "af.h"
42
43 static const char tstr[] = "[|rip]";
44
45 struct rip {
46 uint8_t rip_cmd; /* request/response */
47 uint8_t rip_vers; /* protocol version # */
48 uint8_t unused[2]; /* unused */
49 };
50
51 #define RIPCMD_REQUEST 1 /* want info */
52 #define RIPCMD_RESPONSE 2 /* responding to request */
53 #define RIPCMD_TRACEON 3 /* turn tracing on */
54 #define RIPCMD_TRACEOFF 4 /* turn it off */
55 #define RIPCMD_POLL 5 /* want info from everybody */
56 #define RIPCMD_POLLENTRY 6 /* poll for entry */
57
58 static const struct tok rip_cmd_values[] = {
59 { RIPCMD_REQUEST, "Request" },
60 { RIPCMD_RESPONSE, "Response" },
61 { RIPCMD_TRACEON, "Trace on" },
62 { RIPCMD_TRACEOFF, "Trace off" },
63 { RIPCMD_POLL, "Poll" },
64 { RIPCMD_POLLENTRY, "Poll Entry" },
65 { 0, NULL}
66 };
67
68 #define RIP_AUTHLEN 16
69 #define RIP_ROUTELEN 20
70
71 /*
72 * rfc 1723
73 *
74 * 0 1 2 3 3
75 * 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
76 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
77 * | Command (1) | Version (1) | unused |
78 * +---------------+---------------+-------------------------------+
79 * | Address Family Identifier (2) | Route Tag (2) |
80 * +-------------------------------+-------------------------------+
81 * | IP Address (4) |
82 * +---------------------------------------------------------------+
83 * | Subnet Mask (4) |
84 * +---------------------------------------------------------------+
85 * | Next Hop (4) |
86 * +---------------------------------------------------------------+
87 * | Metric (4) |
88 * +---------------------------------------------------------------+
89 *
90 */
91
92 struct rip_netinfo {
93 uint16_t rip_family;
94 uint16_t rip_tag;
95 uint32_t rip_dest;
96 uint32_t rip_dest_mask;
97 uint32_t rip_router;
98 uint32_t rip_metric; /* cost of route */
99 };
100
101 static void
102 rip_entry_print_v1(netdissect_options *ndo,
103 register const struct rip_netinfo *ni)
104 {
105 register u_short family;
106
107 /* RFC 1058 */
108 family = EXTRACT_16BITS(&ni->rip_family);
109 if (family != BSD_AFNUM_INET && family != 0) {
110 ND_PRINT((ndo, "\n\t AFI %s, ", tok2str(bsd_af_values, "Unknown (%u)", family)));
111 print_unknown_data(ndo, (const uint8_t *)&ni->rip_family, "\n\t ", RIP_ROUTELEN);
112 return;
113 }
114 if (EXTRACT_16BITS(&ni->rip_tag) ||
115 EXTRACT_32BITS(&ni->rip_dest_mask) ||
116 EXTRACT_32BITS(&ni->rip_router)) {
117 /* MBZ fields not zero */
118 print_unknown_data(ndo, (const uint8_t *)&ni->rip_family, "\n\t ", RIP_ROUTELEN);
119 return;
120 }
121 if (family == 0) {
122 ND_PRINT((ndo, "\n\t AFI 0, %s, metric: %u",
123 ipaddr_string(ndo, &ni->rip_dest),
124 EXTRACT_32BITS(&ni->rip_metric)));
125 return;
126 } /* BSD_AFNUM_INET */
127 ND_PRINT((ndo, "\n\t %s, metric: %u",
128 ipaddr_string(ndo, &ni->rip_dest),
129 EXTRACT_32BITS(&ni->rip_metric)));
130 }
131
132 static unsigned
133 rip_entry_print_v2(netdissect_options *ndo,
134 register const struct rip_netinfo *ni, const unsigned remaining)
135 {
136 register u_short family;
137
138 family = EXTRACT_16BITS(&ni->rip_family);
139 if (family == 0xFFFF) { /* variable-sized authentication structures */
140 uint16_t auth_type = EXTRACT_16BITS(&ni->rip_tag);
141 if (auth_type == 2) {
142 register const u_char *p = (const u_char *)&ni->rip_dest;
143 u_int i = 0;
144 ND_PRINT((ndo, "\n\t Simple Text Authentication data: "));
145 for (; i < RIP_AUTHLEN; p++, i++)
146 ND_PRINT((ndo, "%c", ND_ISPRINT(*p) ? *p : '.'));
147 } else if (auth_type == 3) {
148 ND_PRINT((ndo, "\n\t Auth header:"));
149 ND_PRINT((ndo, " Packet Len %u,", EXTRACT_16BITS((const uint8_t *)ni + 4)));
150 ND_PRINT((ndo, " Key-ID %u,", *((const uint8_t *)ni + 6)));
151 ND_PRINT((ndo, " Auth Data Len %u,", *((const uint8_t *)ni + 7)));
152 ND_PRINT((ndo, " SeqNo %u,", EXTRACT_32BITS(&ni->rip_dest_mask)));
153 ND_PRINT((ndo, " MBZ %u,", EXTRACT_32BITS(&ni->rip_router)));
154 ND_PRINT((ndo, " MBZ %u", EXTRACT_32BITS(&ni->rip_metric)));
155 } else if (auth_type == 1) {
156 ND_PRINT((ndo, "\n\t Auth trailer:"));
157 print_unknown_data(ndo, (const uint8_t *)&ni->rip_dest, "\n\t ", remaining);
158 return remaining; /* AT spans till the packet end */
159 } else {
160 ND_PRINT((ndo, "\n\t Unknown (%u) Authentication data:",
161 EXTRACT_16BITS(&ni->rip_tag)));
162 print_unknown_data(ndo, (const uint8_t *)&ni->rip_dest, "\n\t ", remaining);
163 }
164 } else if (family != BSD_AFNUM_INET && family != 0) {
165 ND_PRINT((ndo, "\n\t AFI %s", tok2str(bsd_af_values, "Unknown (%u)", family)));
166 print_unknown_data(ndo, (const uint8_t *)&ni->rip_tag, "\n\t ", RIP_ROUTELEN-2);
167 } else { /* BSD_AFNUM_INET or AFI 0 */
168 ND_PRINT((ndo, "\n\t AFI %s, %15s/%-2d, tag 0x%04x, metric: %u, next-hop: ",
169 tok2str(bsd_af_values, "%u", family),
170 ipaddr_string(ndo, &ni->rip_dest),
171 mask2plen(EXTRACT_32BITS(&ni->rip_dest_mask)),
172 EXTRACT_16BITS(&ni->rip_tag),
173 EXTRACT_32BITS(&ni->rip_metric)));
174 if (EXTRACT_32BITS(&ni->rip_router))
175 ND_PRINT((ndo, "%s", ipaddr_string(ndo, &ni->rip_router)));
176 else
177 ND_PRINT((ndo, "self"));
178 }
179 return sizeof (*ni);
180 }
181
182 void
183 rip_print(netdissect_options *ndo,
184 const u_char *dat, u_int length)
185 {
186 register const struct rip *rp;
187 register const struct rip_netinfo *ni;
188 register u_int i, j;
189
190 if (ndo->ndo_snapend < dat) {
191 ND_PRINT((ndo, " %s", tstr));
192 return;
193 }
194 i = ndo->ndo_snapend - dat;
195 if (i > length)
196 i = length;
197 if (i < sizeof(*rp)) {
198 ND_PRINT((ndo, " %s", tstr));
199 return;
200 }
201 i -= sizeof(*rp);
202
203 rp = (const struct rip *)dat;
204
205 ND_PRINT((ndo, "%sRIPv%u",
206 (ndo->ndo_vflag >= 1) ? "\n\t" : "",
207 rp->rip_vers));
208
209 switch (rp->rip_vers) {
210 case 0:
211 /*
212 * RFC 1058.
213 *
214 * XXX - RFC 1058 says
215 *
216 * 0 Datagrams whose version number is zero are to be ignored.
217 * These are from a previous version of the protocol, whose
218 * packet format was machine-specific.
219 *
220 * so perhaps we should just dump the packet, in hex.
221 */
222 print_unknown_data(ndo, (const uint8_t *)&rp->rip_cmd, "\n\t", length);
223 break;
224 default:
225 /* dump version and lets see if we know the commands name*/
226 ND_PRINT((ndo, ", %s, length: %u",
227 tok2str(rip_cmd_values,
228 "unknown command (%u)",
229 rp->rip_cmd),
230 length));
231
232 if (ndo->ndo_vflag < 1)
233 return;
234
235 switch (rp->rip_cmd) {
236 case RIPCMD_REQUEST:
237 case RIPCMD_RESPONSE:
238 j = length / sizeof(*ni);
239 ND_PRINT((ndo, ", routes: %u%s", j, rp->rip_vers == 2 ? " or less" : ""));
240 ni = (const struct rip_netinfo *)(rp + 1);
241 for (; i >= sizeof(*ni); ++ni) {
242 if (rp->rip_vers == 1)
243 {
244 rip_entry_print_v1(ndo, ni);
245 i -= sizeof(*ni);
246 }
247 else if (rp->rip_vers == 2)
248 i -= rip_entry_print_v2(ndo, ni, i);
249 else
250 break;
251 }
252 if (i)
253 ND_PRINT((ndo, "%s", tstr));
254 break;
255
256 case RIPCMD_TRACEOFF:
257 case RIPCMD_POLL:
258 case RIPCMD_POLLENTRY:
259 break;
260
261 case RIPCMD_TRACEON:
262 /* fall through */
263 default:
264 if (ndo->ndo_vflag <= 1) {
265 if(!print_unknown_data(ndo, (const uint8_t *)rp, "\n\t", length))
266 return;
267 }
268 break;
269 }
270 /* do we want to see an additionally hexdump ? */
271 if (ndo->ndo_vflag> 1) {
272 if(!print_unknown_data(ndo, (const uint8_t *)rp, "\n\t", length))
273 return;
274 }
275 }
276 }
277
278
279