1 /*
2 * Copyright (C) 2002 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 /* \summary: IPv6 mobility printer */
31 /* RFC 3775 */
32
33 #include <config.h>
34
35 #include "netdissect-stdinc.h"
36
37 #include "netdissect.h"
38 #include "addrtoname.h"
39 #include "extract.h"
40
41 #include "ip6.h"
42
43
44 /* Mobility header */
45 struct ip6_mobility {
46 nd_uint8_t ip6m_pproto; /* following payload protocol (for PG) */
47 nd_uint8_t ip6m_len; /* length in units of 8 octets */
48 nd_uint8_t ip6m_type; /* message type */
49 nd_uint8_t reserved; /* reserved */
50 nd_uint16_t ip6m_cksum; /* sum of IPv6 pseudo-header and MH */
51 union {
52 nd_uint16_t ip6m_un_data16[1]; /* type-specific field */
53 nd_uint8_t ip6m_un_data8[2]; /* type-specific field */
54 } ip6m_dataun;
55 };
56
57 #define ip6m_data16 ip6m_dataun.ip6m_un_data16
58 #define ip6m_data8 ip6m_dataun.ip6m_un_data8
59
60 #define IP6M_MINLEN 8
61
62 /* https://www.iana.org/assignments/mobility-parameters/mobility-parameters.xhtml */
63
64 /* message type */
65 #define IP6M_BINDING_REQUEST 0 /* Binding Refresh Request */
66 #define IP6M_HOME_TEST_INIT 1 /* Home Test Init */
67 #define IP6M_CAREOF_TEST_INIT 2 /* Care-of Test Init */
68 #define IP6M_HOME_TEST 3 /* Home Test */
69 #define IP6M_CAREOF_TEST 4 /* Care-of Test */
70 #define IP6M_BINDING_UPDATE 5 /* Binding Update */
71 #define IP6M_BINDING_ACK 6 /* Binding Acknowledgement */
72 #define IP6M_BINDING_ERROR 7 /* Binding Error */
73 #define IP6M_MAX 7
74
75 static const struct tok ip6m_str[] = {
76 { IP6M_BINDING_REQUEST, "BRR" },
77 { IP6M_HOME_TEST_INIT, "HoTI" },
78 { IP6M_CAREOF_TEST_INIT, "CoTI" },
79 { IP6M_HOME_TEST, "HoT" },
80 { IP6M_CAREOF_TEST, "CoT" },
81 { IP6M_BINDING_UPDATE, "BU" },
82 { IP6M_BINDING_ACK, "BA" },
83 { IP6M_BINDING_ERROR, "BE" },
84 { 0, NULL }
85 };
86
87 static const unsigned ip6m_hdrlen[IP6M_MAX + 1] = {
88 IP6M_MINLEN, /* IP6M_BINDING_REQUEST */
89 IP6M_MINLEN + 8, /* IP6M_HOME_TEST_INIT */
90 IP6M_MINLEN + 8, /* IP6M_CAREOF_TEST_INIT */
91 IP6M_MINLEN + 16, /* IP6M_HOME_TEST */
92 IP6M_MINLEN + 16, /* IP6M_CAREOF_TEST */
93 IP6M_MINLEN + 4, /* IP6M_BINDING_UPDATE */
94 IP6M_MINLEN + 4, /* IP6M_BINDING_ACK */
95 IP6M_MINLEN + 16, /* IP6M_BINDING_ERROR */
96 };
97
98 /* Mobility Header Options */
99 #define IP6MOPT_MINLEN 2
100 #define IP6MOPT_PAD1 0x0 /* Pad1 */
101 #define IP6MOPT_PADN 0x1 /* PadN */
102 #define IP6MOPT_REFRESH 0x2 /* Binding Refresh Advice */
103 #define IP6MOPT_REFRESH_MINLEN 4
104 #define IP6MOPT_ALTCOA 0x3 /* Alternate Care-of Address */
105 #define IP6MOPT_ALTCOA_MINLEN 18
106 #define IP6MOPT_NONCEID 0x4 /* Nonce Indices */
107 #define IP6MOPT_NONCEID_MINLEN 6
108 #define IP6MOPT_AUTH 0x5 /* Binding Authorization Data */
109 #define IP6MOPT_AUTH_MINLEN 12
110
111 static const struct tok ip6m_binding_update_bits [] = {
112 { 0x08, "A" },
113 { 0x04, "H" },
114 { 0x02, "L" },
115 { 0x01, "K" },
116 { 0, NULL }
117 };
118
119 static int
mobility_opt_print(netdissect_options * ndo,const u_char * bp,const unsigned len)120 mobility_opt_print(netdissect_options *ndo,
121 const u_char *bp, const unsigned len)
122 {
123 unsigned i, optlen;
124
125 for (i = 0; i < len; i += optlen) {
126 if (GET_U_1(bp + i) == IP6MOPT_PAD1)
127 optlen = 1;
128 else {
129 if (i + 1 < len) {
130 optlen = GET_U_1(bp + i + 1) + 2;
131 } else
132 goto trunc;
133 }
134 if (i + optlen > len)
135 goto trunc;
136 ND_TCHECK_1(bp + i + optlen);
137
138 switch (GET_U_1(bp + i)) {
139 case IP6MOPT_PAD1:
140 ND_PRINT("(pad1)");
141 break;
142 case IP6MOPT_PADN:
143 if (len - i < IP6MOPT_MINLEN) {
144 ND_PRINT("(padn: trunc)");
145 goto trunc;
146 }
147 ND_PRINT("(padn)");
148 break;
149 case IP6MOPT_REFRESH:
150 if (len - i < IP6MOPT_REFRESH_MINLEN) {
151 ND_PRINT("(refresh: trunc)");
152 goto trunc;
153 }
154 /* units of 4 secs */
155 ND_PRINT("(refresh: %u)",
156 GET_BE_U_2(bp + i + 2) << 2);
157 break;
158 case IP6MOPT_ALTCOA:
159 if (len - i < IP6MOPT_ALTCOA_MINLEN) {
160 ND_PRINT("(altcoa: trunc)");
161 goto trunc;
162 }
163 ND_PRINT("(alt-CoA: %s)", GET_IP6ADDR_STRING(bp + i + 2));
164 break;
165 case IP6MOPT_NONCEID:
166 if (len - i < IP6MOPT_NONCEID_MINLEN) {
167 ND_PRINT("(ni: trunc)");
168 goto trunc;
169 }
170 ND_PRINT("(ni: ho=0x%04x co=0x%04x)",
171 GET_BE_U_2(bp + i + 2),
172 GET_BE_U_2(bp + i + 4));
173 break;
174 case IP6MOPT_AUTH:
175 if (len - i < IP6MOPT_AUTH_MINLEN) {
176 ND_PRINT("(auth: trunc)");
177 goto trunc;
178 }
179 ND_PRINT("(auth)");
180 break;
181 default:
182 if (len - i < IP6MOPT_MINLEN) {
183 ND_PRINT("(sopt_type %u: trunc)",
184 GET_U_1(bp + i));
185 goto trunc;
186 }
187 ND_PRINT("(type-0x%02x: len=%u)", GET_U_1(bp + i),
188 GET_U_1(bp + i + 1));
189 break;
190 }
191 }
192 return 0;
193
194 trunc:
195 return 1;
196 }
197
198 /*
199 * Mobility Header
200 */
201 int
mobility_print(netdissect_options * ndo,const u_char * bp,const u_char * bp2 _U_)202 mobility_print(netdissect_options *ndo,
203 const u_char *bp, const u_char *bp2 _U_)
204 {
205 const struct ip6_mobility *mh;
206 const u_char *ep;
207 unsigned mhlen, hlen;
208 uint8_t type;
209
210 ndo->ndo_protocol = "mobility";
211 mh = (const struct ip6_mobility *)bp;
212
213 /* 'ep' points to the end of available data. */
214 ep = ndo->ndo_snapend;
215
216 if (!ND_TTEST_1(mh->ip6m_len)) {
217 /*
218 * There's not enough captured data to include the
219 * mobility header length.
220 *
221 * Our caller expects us to return the length, however,
222 * so return a value that will run to the end of the
223 * captured data.
224 *
225 * XXX - "ip6_print()" doesn't do anything with the
226 * returned length, however, as it breaks out of the
227 * header-processing loop.
228 */
229 mhlen = (unsigned)(ep - bp);
230 goto trunc;
231 }
232 mhlen = (GET_U_1(mh->ip6m_len) + 1) << 3;
233
234 /* XXX ip6m_cksum */
235
236 type = GET_U_1(mh->ip6m_type);
237 if (type <= IP6M_MAX && mhlen < ip6m_hdrlen[type]) {
238 ND_PRINT("(header length %u is too small for type %u)", mhlen, type);
239 goto trunc;
240 }
241 ND_PRINT("mobility: %s", tok2str(ip6m_str, "type-#%u", type));
242 switch (type) {
243 case IP6M_BINDING_REQUEST:
244 hlen = IP6M_MINLEN;
245 break;
246 case IP6M_HOME_TEST_INIT:
247 case IP6M_CAREOF_TEST_INIT:
248 hlen = IP6M_MINLEN;
249 if (ndo->ndo_vflag) {
250 ND_PRINT(" %s Init Cookie=%08x:%08x",
251 type == IP6M_HOME_TEST_INIT ? "Home" : "Care-of",
252 GET_BE_U_4(bp + hlen),
253 GET_BE_U_4(bp + hlen + 4));
254 }
255 hlen += 8;
256 break;
257 case IP6M_HOME_TEST:
258 case IP6M_CAREOF_TEST:
259 ND_PRINT(" nonce id=0x%x", GET_BE_U_2(mh->ip6m_data16[0]));
260 hlen = IP6M_MINLEN;
261 if (ndo->ndo_vflag) {
262 ND_PRINT(" %s Init Cookie=%08x:%08x",
263 type == IP6M_HOME_TEST ? "Home" : "Care-of",
264 GET_BE_U_4(bp + hlen),
265 GET_BE_U_4(bp + hlen + 4));
266 }
267 hlen += 8;
268 if (ndo->ndo_vflag) {
269 ND_PRINT(" %s Keygen Token=%08x:%08x",
270 type == IP6M_HOME_TEST ? "Home" : "Care-of",
271 GET_BE_U_4(bp + hlen),
272 GET_BE_U_4(bp + hlen + 4));
273 }
274 hlen += 8;
275 break;
276 case IP6M_BINDING_UPDATE:
277 {
278 int bits;
279 ND_PRINT(" seq#=%u", GET_BE_U_2(mh->ip6m_data16[0]));
280 hlen = IP6M_MINLEN;
281 ND_TCHECK_2(bp + hlen);
282 bits = (GET_U_1(bp + hlen) & 0xf0) >> 4;
283 if (bits) {
284 ND_PRINT(" ");
285 ND_PRINT("%s",
286 bittok2str_nosep(ip6m_binding_update_bits,
287 "bits-#0x%x", bits));
288 }
289 /* Reserved (4bits) */
290 hlen += 1;
291 /* Reserved (8bits) */
292 hlen += 1;
293 /* units of 4 secs */
294 ND_PRINT(" lifetime=%u", GET_BE_U_2(bp + hlen) << 2);
295 hlen += 2;
296 break;
297 }
298 case IP6M_BINDING_ACK:
299 ND_PRINT(" status=%u", GET_U_1(mh->ip6m_data8[0]));
300 if (GET_U_1(mh->ip6m_data8[1]) & 0x80)
301 ND_PRINT(" K");
302 /* Reserved (7bits) */
303 hlen = IP6M_MINLEN;
304 ND_PRINT(" seq#=%u", GET_BE_U_2(bp + hlen));
305 hlen += 2;
306 /* units of 4 secs */
307 ND_PRINT(" lifetime=%u", GET_BE_U_2(bp + hlen) << 2);
308 hlen += 2;
309 break;
310 case IP6M_BINDING_ERROR:
311 ND_PRINT(" status=%u", GET_U_1(mh->ip6m_data8[0]));
312 /* Reserved */
313 hlen = IP6M_MINLEN;
314 ND_PRINT(" homeaddr %s", GET_IP6ADDR_STRING(bp + hlen));
315 hlen += 16;
316 break;
317 default:
318 ND_PRINT(" len=%u", GET_U_1(mh->ip6m_len));
319 return(mhlen);
320 break;
321 }
322 if (ndo->ndo_vflag)
323 if (mobility_opt_print(ndo, bp + hlen, mhlen - hlen))
324 goto trunc;
325
326 return(mhlen);
327
328 trunc:
329 nd_print_trunc(ndo);
330 return(-1);
331 }
332