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1 /*

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 */

30 /* \summary: IPv6 mobility printer */

31 /* RFC 3775 */

33 #ifdef HAVE_CONFIG_H

34 #include <config.h>

35 #endif

37 #include "netdissect-stdinc.h"

39 #include "netdissect.h"

40 #include "addrtoname.h"

41 #include "extract.h"

43 #include "ip6.h"

46 /* Mobility header */

47 struct ip6_mobility {

48 nd_uint8_t ip6m_pproto; /* following payload protocol (for PG) */

49 nd_uint8_t ip6m_len; /* length in units of 8 octets */

50 nd_uint8_t ip6m_type; /* message type */

51 nd_uint8_t reserved; /* reserved */

52 nd_uint16_t ip6m_cksum; /* sum of IPv6 pseudo-header and MH */

53 union {

54 nd_uint16_t ip6m_un_data16[1]; /* type-specific field */

55 nd_uint8_t ip6m_un_data8[2]; /* type-specific field */

56 } ip6m_dataun;

57 };

59 #define ip6m_data16 ip6m_dataun.ip6m_un_data16

60 #define ip6m_data8 ip6m_dataun.ip6m_un_data8

62 #define IP6M_MINLEN 8

64 /* http://www.iana.org/assignments/mobility-parameters/mobility-parameters.xhtml */

66 /* message type */

67 #define IP6M_BINDING_REQUEST 0 /* Binding Refresh Request */

68 #define IP6M_HOME_TEST_INIT 1 /* Home Test Init */

69 #define IP6M_CAREOF_TEST_INIT 2 /* Care-of Test Init */

70 #define IP6M_HOME_TEST 3 /* Home Test */

71 #define IP6M_CAREOF_TEST 4 /* Care-of Test */

72 #define IP6M_BINDING_UPDATE 5 /* Binding Update */

73 #define IP6M_BINDING_ACK 6 /* Binding Acknowledgement */

74 #define IP6M_BINDING_ERROR 7 /* Binding Error */

75 #define IP6M_MAX 7

77 static const struct tok ip6m_str[] = {

78 { IP6M_BINDING_REQUEST, "BRR" },

79 { IP6M_HOME_TEST_INIT, "HoTI" },

80 { IP6M_CAREOF_TEST_INIT, "CoTI" },

81 { IP6M_HOME_TEST, "HoT" },

82 { IP6M_CAREOF_TEST, "CoT" },

83 { IP6M_BINDING_UPDATE, "BU" },

84 { IP6M_BINDING_ACK, "BA" },

85 { IP6M_BINDING_ERROR, "BE" },

86 { 0, NULL }

87 };

 static const unsigned ip6m_hdrlen[IP6M_MAX + 1] = {

90 IP6M_MINLEN, /* IP6M_BINDING_REQUEST */

91 IP6M_MINLEN + 8, /* IP6M_HOME_TEST_INIT */

92 IP6M_MINLEN + 8, /* IP6M_CAREOF_TEST_INIT */

93 IP6M_MINLEN + 16, /* IP6M_HOME_TEST */

94 IP6M_MINLEN + 16, /* IP6M_CAREOF_TEST */

95 IP6M_MINLEN + 4, /* IP6M_BINDING_UPDATE */

96 IP6M_MINLEN + 4, /* IP6M_BINDING_ACK */

97 IP6M_MINLEN + 16, /* IP6M_BINDING_ERROR */

98 };

100 /* Mobility Header Options */

101 #define IP6MOPT_MINLEN 2

102 #define IP6MOPT_PAD1 0x0 /* Pad1 */

103 #define IP6MOPT_PADN 0x1 /* PadN */

104 #define IP6MOPT_REFRESH 0x2 /* Binding Refresh Advice */

105 #define IP6MOPT_REFRESH_MINLEN 4

106 #define IP6MOPT_ALTCOA 0x3 /* Alternate Care-of Address */

107 #define IP6MOPT_ALTCOA_MINLEN 18

108 #define IP6MOPT_NONCEID 0x4 /* Nonce Indices */

109 #define IP6MOPT_NONCEID_MINLEN 6

110 #define IP6MOPT_AUTH 0x5 /* Binding Authorization Data */

111 #define IP6MOPT_AUTH_MINLEN 12

112

113 static int

114 mobility_opt_print(netdissect_options *ndo,

                    const u_char *bp, const unsigned len)

116 {

117 unsigned i, optlen;

118

         for (i = 0; i < len; i += optlen) {

120 ND_TCHECK_1(bp + i);

                 if (EXTRACT_U_1(bp + i) == IP6MOPT_PAD1)

122 optlen = 1;

123 else {

                         if (i + 1 < len) {

                                 ND_TCHECK_1(bp + i + 1);

                                 optlen = EXTRACT_U_1(bp + i + 1) + 2;

127 }

128 else

129 goto trunc;

130 }

                 if (i + optlen > len)

132 goto trunc;

                 ND_TCHECK_1(bp + i + optlen);

134

                 switch (EXTRACT_U_1(bp + i)) {

136 case IP6MOPT_PAD1:

137 ND_PRINT("(pad1)");

138 break;

139 case IP6MOPT_PADN:

                         if (len - i < IP6MOPT_MINLEN) {

141 ND_PRINT("(padn: trunc)");

142 goto trunc;

143 }

144 ND_PRINT("(padn)");

145 break;

146 case IP6MOPT_REFRESH:

                         if (len - i < IP6MOPT_REFRESH_MINLEN) {

148 ND_PRINT("(refresh: trunc)");

149 goto trunc;

150 }

151 /* units of 4 secs */

                         ND_TCHECK_2(bp + i + 2);

153 ND_PRINT("(refresh: %u)",

                                 EXTRACT_BE_U_2(bp + i + 2) << 2);

155 break;

156 case IP6MOPT_ALTCOA:

                         if (len - i < IP6MOPT_ALTCOA_MINLEN) {

158 ND_PRINT("(altcoa: trunc)");

159 goto trunc;

160 }

                         ND_TCHECK_16(bp + i + 2);

                         ND_PRINT("(alt-CoA: %s)", ip6addr_string(ndo, bp + i + 2));

163 break;

164 case IP6MOPT_NONCEID:

                         if (len - i < IP6MOPT_NONCEID_MINLEN) {

166 ND_PRINT("(ni: trunc)");

167 goto trunc;

168 }

                         ND_TCHECK_2(bp + i + 2);

                         ND_TCHECK_2(bp + i + 4);

171 ND_PRINT("(ni: ho=0x%04x co=0x%04x)",

                                 EXTRACT_BE_U_2(bp + i + 2),

                                 EXTRACT_BE_U_2(bp + i + 4));

174 break;

175 case IP6MOPT_AUTH:

                         if (len - i < IP6MOPT_AUTH_MINLEN) {

177 ND_PRINT("(auth: trunc)");

178 goto trunc;

179 }

180 ND_PRINT("(auth)");

181 break;

182 default:

                         if (len - i < IP6MOPT_MINLEN) {

                                 ND_PRINT("(sopt_type %u: trunc)", EXTRACT_U_1(bp + i));

185 goto trunc;

186 }

                         ND_PRINT("(type-0x%02x: len=%u)", EXTRACT_U_1(bp + i), EXTRACT_U_1(bp + i + 1));

188 break;

189 }

190 }

191 return 0;

192

193 trunc:

194 return 1;

195 }

196

197 /*

198 * Mobility Header

199 */

200 int

201 mobility_print(netdissect_options *ndo,

                const u_char *bp, const u_char *bp2 _U_)

203 {

204 const struct ip6_mobility *mh;

205 const u_char *ep;

206 unsigned mhlen, hlen;

207 uint8_t type;

208

209 ndo->ndo_protocol = "mobility";

210 mh = (const struct ip6_mobility *)bp;

211

212 /* 'ep' points to the end of available data. */

213 ep = ndo->ndo_snapend;

214

         if (!ND_TTEST_1(mh->ip6m_len)) {

216 /*

217 * There's not enough captured data to include the

218 * mobility header length.

219 *

220 * Our caller expects us to return the length, however,

221 * so return a value that will run to the end of the

222 * captured data.

223 *

224 * XXX - "ip6_print()" doesn't do anything with the

225 * returned length, however, as it breaks out of the

226 * header-processing loop.

227 */

228 mhlen = ep - bp;

229 goto trunc;

230 }

         mhlen = (EXTRACT_U_1(mh->ip6m_len) + 1) << 3;

232

233 /* XXX ip6m_cksum */

234

235 ND_TCHECK_1(mh->ip6m_type);

         type = EXTRACT_U_1(mh->ip6m_type);

         if (type <= IP6M_MAX && mhlen < ip6m_hdrlen[type]) {

                 ND_PRINT("(header length %u is too small for type %u)", mhlen, type);

239 goto trunc;

240 }

         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) {

                         ND_TCHECK_4(bp + hlen + 4);

251 ND_PRINT(" %s Init Cookie=%08x:%08x",

                                type == IP6M_HOME_TEST_INIT ? "Home" : "Care-of",

253 EXTRACT_BE_U_4(bp + hlen),

                                EXTRACT_BE_U_4(bp + hlen + 4));

255 }

256 hlen += 8;

257 break;

258 case IP6M_HOME_TEST:

259 case IP6M_CAREOF_TEST:

                 ND_TCHECK_2(mh->ip6m_data16[0]);

                 ND_PRINT(" nonce id=0x%x", EXTRACT_BE_U_2(mh->ip6m_data16[0]));

262 hlen = IP6M_MINLEN;

263 if (ndo->ndo_vflag) {

                         ND_TCHECK_4(bp + hlen + 4);

265 ND_PRINT(" %s Init Cookie=%08x:%08x",

                                type == IP6M_HOME_TEST ? "Home" : "Care-of",

267 EXTRACT_BE_U_4(bp + hlen),

                                EXTRACT_BE_U_4(bp + hlen + 4));

269 }

270 hlen += 8;

271 if (ndo->ndo_vflag) {

                         ND_TCHECK_4(bp + hlen + 4);

273 ND_PRINT(" %s Keygen Token=%08x:%08x",

                                type == IP6M_HOME_TEST ? "Home" : "Care-of",

275 EXTRACT_BE_U_4(bp + hlen),

                                EXTRACT_BE_U_4(bp + hlen + 4));

277 }

278 hlen += 8;

279 break;

280 case IP6M_BINDING_UPDATE:

                 ND_TCHECK_2(mh->ip6m_data16[0]);

                 ND_PRINT(" seq#=%u", EXTRACT_BE_U_2(mh->ip6m_data16[0]));

283 hlen = IP6M_MINLEN;

284 ND_TCHECK_2(bp + hlen);

                 if (EXTRACT_U_1(bp + hlen) & 0xf0) {

286 ND_PRINT(" ");

                         if (EXTRACT_U_1(bp + hlen) & 0x80)

288 ND_PRINT("A");

                         if (EXTRACT_U_1(bp + hlen) & 0x40)

290 ND_PRINT("H");

                         if (EXTRACT_U_1(bp + hlen) & 0x20)

292 ND_PRINT("L");

                         if (EXTRACT_U_1(bp + hlen) & 0x10)

294 ND_PRINT("K");

295 }

296 /* Reserved (4bits) */

297 hlen += 1;

298 /* Reserved (8bits) */

299 hlen += 1;

300 ND_TCHECK_2(bp + hlen);

301 /* units of 4 secs */

                 ND_PRINT(" lifetime=%u", EXTRACT_BE_U_2(bp + hlen) << 2);

303 hlen += 2;

304 break;

305 case IP6M_BINDING_ACK:

                 ND_TCHECK_1(mh->ip6m_data8[0]);

                 ND_PRINT(" status=%u", EXTRACT_U_1(mh->ip6m_data8[0]));

                 ND_TCHECK_1(mh->ip6m_data8[1]);

                 if (EXTRACT_U_1(mh->ip6m_data8[1]) & 0x80)

310 ND_PRINT(" K");

311 /* Reserved (7bits) */

312 hlen = IP6M_MINLEN;

313 ND_TCHECK_2(bp + hlen);

                 ND_PRINT(" seq#=%u", EXTRACT_BE_U_2(bp + hlen));

315 hlen += 2;

316 ND_TCHECK_2(bp + hlen);

317 /* units of 4 secs */

                 ND_PRINT(" lifetime=%u", EXTRACT_BE_U_2(bp + hlen) << 2);

319 hlen += 2;

320 break;

321 case IP6M_BINDING_ERROR:

                 ND_TCHECK_1(mh->ip6m_data8[0]);

                 ND_PRINT(" status=%u", EXTRACT_U_1(mh->ip6m_data8[0]));

324 /* Reserved */

325 hlen = IP6M_MINLEN;

326 ND_TCHECK_16(bp + hlen);

                 ND_PRINT(" homeaddr %s", ip6addr_string(ndo, bp + hlen));

328 hlen += 16;

329 break;

330 default:

                 ND_PRINT(" len=%u", EXTRACT_U_1(mh->ip6m_len));

332 return(mhlen);

333 break;

334 }

335 if (ndo->ndo_vflag)

                 if (mobility_opt_print(ndo, bp + hlen, mhlen - hlen))

337 goto trunc;

338

339 return(mhlen);

340

341 trunc:

342 nd_print_trunc(ndo);

343 return(-1);

344 }