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 /* \summary: Routing Information Protocol (RIP) printer */
23
24 #ifdef HAVE_CONFIG_H
25 #include "config.h"
26 #endif
27
28 #include <netdissect-stdinc.h>
29
30 #include <stdio.h>
31
32 #include "netdissect.h"
33 #include "addrtoname.h"
34 #include "extract.h"
35
36 #include "af.h"
37
38 static const char tstr[] = "[|rip]";
39
40 struct rip {
41 uint8_t rip_cmd; /* request/response */
42 uint8_t rip_vers; /* protocol version # */
43 uint8_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 uint16_t rip_family;
89 uint16_t rip_tag;
90 uint32_t rip_dest;
91 uint32_t rip_dest_mask;
92 uint32_t rip_router;
93 uint32_t rip_metric; /* cost of route */
94 };
95
96 static void
rip_entry_print_v1(netdissect_options * ndo,register const struct rip_netinfo * ni)97 rip_entry_print_v1(netdissect_options *ndo,
98 register const struct rip_netinfo *ni)
99 {
100 register u_short family;
101
102 /* RFC 1058 */
103 family = EXTRACT_16BITS(&ni->rip_family);
104 if (family != BSD_AFNUM_INET && family != 0) {
105 ND_PRINT((ndo, "\n\t AFI %s, ", tok2str(bsd_af_values, "Unknown (%u)", family)));
106 print_unknown_data(ndo, (const uint8_t *)&ni->rip_family, "\n\t ", RIP_ROUTELEN);
107 return;
108 }
109 if (EXTRACT_16BITS(&ni->rip_tag) ||
110 EXTRACT_32BITS(&ni->rip_dest_mask) ||
111 EXTRACT_32BITS(&ni->rip_router)) {
112 /* MBZ fields not zero */
113 print_unknown_data(ndo, (const uint8_t *)&ni->rip_family, "\n\t ", RIP_ROUTELEN);
114 return;
115 }
116 if (family == 0) {
117 ND_PRINT((ndo, "\n\t AFI 0, %s, metric: %u",
118 ipaddr_string(ndo, &ni->rip_dest),
119 EXTRACT_32BITS(&ni->rip_metric)));
120 return;
121 } /* BSD_AFNUM_INET */
122 ND_PRINT((ndo, "\n\t %s, metric: %u",
123 ipaddr_string(ndo, &ni->rip_dest),
124 EXTRACT_32BITS(&ni->rip_metric)));
125 }
126
127 static unsigned
rip_entry_print_v2(netdissect_options * ndo,register const struct rip_netinfo * ni,const unsigned remaining)128 rip_entry_print_v2(netdissect_options *ndo,
129 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 uint16_t auth_type = EXTRACT_16BITS(&ni->rip_tag);
136 if (auth_type == 2) {
137 register const u_char *p = (const u_char *)&ni->rip_dest;
138 u_int i = 0;
139 ND_PRINT((ndo, "\n\t Simple Text Authentication data: "));
140 for (; i < RIP_AUTHLEN; p++, i++)
141 ND_PRINT((ndo, "%c", ND_ISPRINT(*p) ? *p : '.'));
142 } else if (auth_type == 3) {
143 ND_PRINT((ndo, "\n\t Auth header:"));
144 ND_PRINT((ndo, " Packet Len %u,", EXTRACT_16BITS((const uint8_t *)ni + 4)));
145 ND_PRINT((ndo, " Key-ID %u,", *((const uint8_t *)ni + 6)));
146 ND_PRINT((ndo, " Auth Data Len %u,", *((const uint8_t *)ni + 7)));
147 ND_PRINT((ndo, " SeqNo %u,", EXTRACT_32BITS(&ni->rip_dest_mask)));
148 ND_PRINT((ndo, " MBZ %u,", EXTRACT_32BITS(&ni->rip_router)));
149 ND_PRINT((ndo, " MBZ %u", EXTRACT_32BITS(&ni->rip_metric)));
150 } else if (auth_type == 1) {
151 ND_PRINT((ndo, "\n\t Auth trailer:"));
152 print_unknown_data(ndo, (const uint8_t *)&ni->rip_dest, "\n\t ", remaining);
153 return remaining; /* AT spans till the packet end */
154 } else {
155 ND_PRINT((ndo, "\n\t Unknown (%u) Authentication data:",
156 EXTRACT_16BITS(&ni->rip_tag)));
157 print_unknown_data(ndo, (const uint8_t *)&ni->rip_dest, "\n\t ", remaining);
158 }
159 } else if (family != BSD_AFNUM_INET && family != 0) {
160 ND_PRINT((ndo, "\n\t AFI %s", tok2str(bsd_af_values, "Unknown (%u)", family)));
161 print_unknown_data(ndo, (const uint8_t *)&ni->rip_tag, "\n\t ", RIP_ROUTELEN-2);
162 } else { /* BSD_AFNUM_INET or AFI 0 */
163 ND_PRINT((ndo, "\n\t AFI %s, %15s/%-2d, tag 0x%04x, metric: %u, next-hop: ",
164 tok2str(bsd_af_values, "%u", family),
165 ipaddr_string(ndo, &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 ND_PRINT((ndo, "%s", ipaddr_string(ndo, &ni->rip_router)));
171 else
172 ND_PRINT((ndo, "self"));
173 }
174 return sizeof (*ni);
175 }
176
177 void
rip_print(netdissect_options * ndo,const u_char * dat,u_int length)178 rip_print(netdissect_options *ndo,
179 const u_char *dat, u_int length)
180 {
181 register const struct rip *rp;
182 register const struct rip_netinfo *ni;
183 register u_int i, j;
184
185 if (ndo->ndo_snapend < dat) {
186 ND_PRINT((ndo, " %s", tstr));
187 return;
188 }
189 i = ndo->ndo_snapend - dat;
190 if (i > length)
191 i = length;
192 if (i < sizeof(*rp)) {
193 ND_PRINT((ndo, " %s", tstr));
194 return;
195 }
196 i -= sizeof(*rp);
197
198 rp = (const struct rip *)dat;
199
200 ND_PRINT((ndo, "%sRIPv%u",
201 (ndo->ndo_vflag >= 1) ? "\n\t" : "",
202 rp->rip_vers));
203
204 switch (rp->rip_vers) {
205 case 0:
206 /*
207 * RFC 1058.
208 *
209 * XXX - RFC 1058 says
210 *
211 * 0 Datagrams whose version number is zero are to be ignored.
212 * These are from a previous version of the protocol, whose
213 * packet format was machine-specific.
214 *
215 * so perhaps we should just dump the packet, in hex.
216 */
217 print_unknown_data(ndo, (const uint8_t *)&rp->rip_cmd, "\n\t", length);
218 break;
219 default:
220 /* dump version and lets see if we know the commands name*/
221 ND_PRINT((ndo, ", %s, length: %u",
222 tok2str(rip_cmd_values,
223 "unknown command (%u)",
224 rp->rip_cmd),
225 length));
226
227 if (ndo->ndo_vflag < 1)
228 return;
229
230 switch (rp->rip_cmd) {
231 case RIPCMD_REQUEST:
232 case RIPCMD_RESPONSE:
233 j = length / sizeof(*ni);
234 ND_PRINT((ndo, ", routes: %u%s", j, rp->rip_vers == 2 ? " or less" : ""));
235 ni = (const struct rip_netinfo *)(rp + 1);
236 for (; i >= sizeof(*ni); ++ni) {
237 if (rp->rip_vers == 1)
238 {
239 rip_entry_print_v1(ndo, ni);
240 i -= sizeof(*ni);
241 }
242 else if (rp->rip_vers == 2)
243 i -= rip_entry_print_v2(ndo, ni, i);
244 else
245 break;
246 }
247 if (i)
248 ND_PRINT((ndo, "%s", tstr));
249 break;
250
251 case RIPCMD_TRACEOFF:
252 case RIPCMD_POLL:
253 case RIPCMD_POLLENTRY:
254 break;
255
256 case RIPCMD_TRACEON:
257 /* fall through */
258 default:
259 if (ndo->ndo_vflag <= 1) {
260 if(!print_unknown_data(ndo, (const uint8_t *)rp, "\n\t", length))
261 return;
262 }
263 break;
264 }
265 /* do we want to see an additionally hexdump ? */
266 if (ndo->ndo_vflag> 1) {
267 if(!print_unknown_data(ndo, (const uint8_t *)rp, "\n\t", length))
268 return;
269 }
270 }
271 }
272
273
274