1 /** 2 * Copyright (c) 2012 3 * 4 * Gregory Detal <gregory.detal (at) uclouvain.be> 5 * Christoph Paasch <christoph.paasch (at) uclouvain.be> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * 3. Neither the name of the University nor of the Laboratory may be used 19 * to endorse or promote products derived from this software without 20 * specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #define NETDISSECT_REWORKED 36 #ifdef HAVE_CONFIG_H 37 #include "config.h" 38 #endif 39 40 #include <tcpdump-stdinc.h> 41 42 #include "interface.h" 43 #include "extract.h" 44 #include "addrtoname.h" 45 46 #include "tcp.h" 47 48 #define MPTCP_SUB_CAPABLE 0x0 49 #define MPTCP_SUB_JOIN 0x1 50 #define MPTCP_SUB_DSS 0x2 51 #define MPTCP_SUB_ADD_ADDR 0x3 52 #define MPTCP_SUB_REMOVE_ADDR 0x4 53 #define MPTCP_SUB_PRIO 0x5 54 #define MPTCP_SUB_FAIL 0x6 55 #define MPTCP_SUB_FCLOSE 0x7 56 57 struct mptcp_option { 58 uint8_t kind; 59 uint8_t len; 60 uint8_t sub_etc; /* subtype upper 4 bits, other stuff lower 4 bits */ 61 }; 62 63 #define MPTCP_OPT_SUBTYPE(sub_etc) (((sub_etc) >> 4) & 0xF) 64 65 struct mp_capable { 66 uint8_t kind; 67 uint8_t len; 68 uint8_t sub_ver; 69 uint8_t flags; 70 uint8_t sender_key[8]; 71 uint8_t receiver_key[8]; 72 }; 73 74 #define MP_CAPABLE_OPT_VERSION(sub_ver) (((sub_ver) >> 0) & 0xF) 75 #define MP_CAPABLE_C 0x80 76 #define MP_CAPABLE_S 0x01 77 78 struct mp_join { 79 uint8_t kind; 80 uint8_t len; 81 uint8_t sub_b; 82 uint8_t addr_id; 83 union { 84 struct { 85 uint8_t token[4]; 86 uint8_t nonce[4]; 87 } syn; 88 struct { 89 uint8_t mac[8]; 90 uint8_t nonce[4]; 91 } synack; 92 struct { 93 uint8_t mac[20]; 94 } ack; 95 } u; 96 }; 97 98 #define MP_JOIN_B 0x01 99 100 struct mp_dss { 101 uint8_t kind; 102 uint8_t len; 103 uint8_t sub; 104 uint8_t flags; 105 }; 106 107 #define MP_DSS_F 0x10 108 #define MP_DSS_m 0x08 109 #define MP_DSS_M 0x04 110 #define MP_DSS_a 0x02 111 #define MP_DSS_A 0x01 112 113 struct mp_add_addr { 114 uint8_t kind; 115 uint8_t len; 116 uint8_t sub_ipver; 117 uint8_t addr_id; 118 union { 119 struct { 120 uint8_t addr[4]; 121 uint8_t port[2]; 122 } v4; 123 struct { 124 uint8_t addr[16]; 125 uint8_t port[2]; 126 } v6; 127 } u; 128 }; 129 130 #define MP_ADD_ADDR_IPVER(sub_ipver) (((sub_ipver) >> 0) & 0xF) 131 132 struct mp_remove_addr { 133 uint8_t kind; 134 uint8_t len; 135 uint8_t sub; 136 /* list of addr_id */ 137 uint8_t addrs_id; 138 }; 139 140 struct mp_fail { 141 uint8_t kind; 142 uint8_t len; 143 uint8_t sub; 144 uint8_t resv; 145 uint8_t data_seq[8]; 146 }; 147 148 struct mp_close { 149 uint8_t kind; 150 uint8_t len; 151 uint8_t sub; 152 uint8_t rsv; 153 uint8_t key[8]; 154 }; 155 156 struct mp_prio { 157 uint8_t kind; 158 uint8_t len; 159 uint8_t sub_b; 160 uint8_t addr_id; 161 }; 162 163 #define MP_PRIO_B 0x01 164 165 static int 166 dummy_print(netdissect_options *ndo _U_, 167 const u_char *opt _U_, u_int opt_len _U_, u_char flags _U_) 168 { 169 return 1; 170 } 171 172 static int 173 mp_capable_print(netdissect_options *ndo, 174 const u_char *opt, u_int opt_len, u_char flags) 175 { 176 struct mp_capable *mpc = (struct mp_capable *) opt; 177 178 if (!(opt_len == 12 && flags & TH_SYN) && 179 !(opt_len == 20 && (flags & (TH_SYN | TH_ACK)) == TH_ACK)) 180 return 0; 181 182 if (MP_CAPABLE_OPT_VERSION(mpc->sub_ver) != 0) { 183 ND_PRINT((ndo, " Unknown Version (%d)", MP_CAPABLE_OPT_VERSION(mpc->sub_ver))); 184 return 1; 185 } 186 187 if (mpc->flags & MP_CAPABLE_C) 188 ND_PRINT((ndo, " csum")); 189 ND_PRINT((ndo, " {0x%" PRIx64, EXTRACT_64BITS(mpc->sender_key))); 190 if (opt_len == 20) /* ACK */ 191 ND_PRINT((ndo, ",0x%" PRIx64, EXTRACT_64BITS(mpc->receiver_key))); 192 ND_PRINT((ndo, "}")); 193 return 1; 194 } 195 196 static int 197 mp_join_print(netdissect_options *ndo, 198 const u_char *opt, u_int opt_len, u_char flags) 199 { 200 struct mp_join *mpj = (struct mp_join *) opt; 201 202 if (!(opt_len == 12 && flags & TH_SYN) && 203 !(opt_len == 16 && (flags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK)) && 204 !(opt_len == 24 && flags & TH_ACK)) 205 return 0; 206 207 if (opt_len != 24) { 208 if (mpj->sub_b & MP_JOIN_B) 209 ND_PRINT((ndo, " backup")); 210 ND_PRINT((ndo, " id %u", mpj->addr_id)); 211 } 212 213 switch (opt_len) { 214 case 12: /* SYN */ 215 ND_PRINT((ndo, " token 0x%x" " nonce 0x%x", 216 EXTRACT_32BITS(mpj->u.syn.token), 217 EXTRACT_32BITS(mpj->u.syn.nonce))); 218 break; 219 case 16: /* SYN/ACK */ 220 ND_PRINT((ndo, " hmac 0x%" PRIx64 " nonce 0x%x", 221 EXTRACT_64BITS(mpj->u.synack.mac), 222 EXTRACT_32BITS(mpj->u.synack.nonce))); 223 break; 224 case 24: {/* ACK */ 225 size_t i; 226 ND_PRINT((ndo, " hmac 0x")); 227 for (i = 0; i < sizeof(mpj->u.ack.mac); ++i) 228 ND_PRINT((ndo, "%02x", mpj->u.ack.mac[i])); 229 } 230 default: 231 break; 232 } 233 return 1; 234 } 235 236 static u_int mp_dss_len(struct mp_dss *m, int csum) 237 { 238 u_int len; 239 240 len = 4; 241 if (m->flags & MP_DSS_A) { 242 /* Ack present - 4 or 8 octets */ 243 len += (m->flags & MP_DSS_a) ? 8 : 4; 244 } 245 if (m->flags & MP_DSS_M) { 246 /* 247 * Data Sequence Number (DSN), Subflow Sequence Number (SSN), 248 * Data-Level Length present, and Checksum possibly present. 249 * All but the Checksum are 10 bytes if the m flag is 250 * clear (4-byte DSN) and 14 bytes if the m flag is set 251 * (8-byte DSN). 252 */ 253 len += (m->flags & MP_DSS_m) ? 14 : 10; 254 255 /* 256 * The Checksum is present only if negotiated. 257 */ 258 if (csum) 259 len += 2; 260 } 261 return len; 262 } 263 264 static int 265 mp_dss_print(netdissect_options *ndo, 266 const u_char *opt, u_int opt_len, u_char flags) 267 { 268 struct mp_dss *mdss = (struct mp_dss *) opt; 269 270 if ((opt_len != mp_dss_len(mdss, 1) && 271 opt_len != mp_dss_len(mdss, 0)) || flags & TH_SYN) 272 return 0; 273 274 if (mdss->flags & MP_DSS_F) 275 ND_PRINT((ndo, " fin")); 276 277 opt += 4; 278 if (mdss->flags & MP_DSS_A) { 279 ND_PRINT((ndo, " ack ")); 280 if (mdss->flags & MP_DSS_a) { 281 ND_PRINT((ndo, "%" PRIu64, EXTRACT_64BITS(opt))); 282 opt += 8; 283 } else { 284 ND_PRINT((ndo, "%u", EXTRACT_32BITS(opt))); 285 opt += 4; 286 } 287 } 288 289 if (mdss->flags & MP_DSS_M) { 290 ND_PRINT((ndo, " seq ")); 291 if (mdss->flags & MP_DSS_m) { 292 ND_PRINT((ndo, "%" PRIu64, EXTRACT_64BITS(opt))); 293 opt += 8; 294 } else { 295 ND_PRINT((ndo, "%u", EXTRACT_32BITS(opt))); 296 opt += 4; 297 } 298 ND_PRINT((ndo, " subseq %u", EXTRACT_32BITS(opt))); 299 opt += 4; 300 ND_PRINT((ndo, " len %u", EXTRACT_16BITS(opt))); 301 opt += 2; 302 303 if (opt_len == mp_dss_len(mdss, 1)) 304 ND_PRINT((ndo, " csum 0x%x", EXTRACT_16BITS(opt))); 305 } 306 return 1; 307 } 308 309 static int 310 add_addr_print(netdissect_options *ndo, 311 const u_char *opt, u_int opt_len, u_char flags _U_) 312 { 313 struct mp_add_addr *add_addr = (struct mp_add_addr *) opt; 314 u_int ipver = MP_ADD_ADDR_IPVER(add_addr->sub_ipver); 315 316 if (!((opt_len == 8 || opt_len == 10) && ipver == 4) && 317 !((opt_len == 20 || opt_len == 22) && ipver == 6)) 318 return 0; 319 320 ND_PRINT((ndo, " id %u", add_addr->addr_id)); 321 switch (ipver) { 322 case 4: 323 ND_PRINT((ndo, " %s", ipaddr_string(ndo, add_addr->u.v4.addr))); 324 if (opt_len == 10) 325 ND_PRINT((ndo, ":%u", EXTRACT_16BITS(add_addr->u.v4.port))); 326 break; 327 case 6: 328 #ifdef INET6 329 ND_PRINT((ndo, " %s", ip6addr_string(ndo, add_addr->u.v6.addr))); 330 #endif 331 if (opt_len == 22) 332 ND_PRINT((ndo, ":%u", EXTRACT_16BITS(add_addr->u.v6.port))); 333 break; 334 default: 335 return 0; 336 } 337 338 return 1; 339 } 340 341 static int 342 remove_addr_print(netdissect_options *ndo, 343 const u_char *opt, u_int opt_len, u_char flags _U_) 344 { 345 struct mp_remove_addr *remove_addr = (struct mp_remove_addr *) opt; 346 uint8_t *addr_id = &remove_addr->addrs_id; 347 348 if (opt_len < 4) 349 return 0; 350 351 opt_len -= 3; 352 ND_PRINT((ndo, " id")); 353 while (opt_len--) 354 ND_PRINT((ndo, " %u", *addr_id++)); 355 return 1; 356 } 357 358 static int 359 mp_prio_print(netdissect_options *ndo, 360 const u_char *opt, u_int opt_len, u_char flags _U_) 361 { 362 struct mp_prio *mpp = (struct mp_prio *) opt; 363 364 if (opt_len != 3 && opt_len != 4) 365 return 0; 366 367 if (mpp->sub_b & MP_PRIO_B) 368 ND_PRINT((ndo, " backup")); 369 else 370 ND_PRINT((ndo, " non-backup")); 371 if (opt_len == 4) 372 ND_PRINT((ndo, " id %u", mpp->addr_id)); 373 374 return 1; 375 } 376 377 static int 378 mp_fail_print(netdissect_options *ndo, 379 const u_char *opt, u_int opt_len, u_char flags _U_) 380 { 381 if (opt_len != 12) 382 return 0; 383 384 ND_PRINT((ndo, " seq %" PRIu64, EXTRACT_64BITS(opt + 4))); 385 return 1; 386 } 387 388 static int 389 mp_fast_close_print(netdissect_options *ndo, 390 const u_char *opt, u_int opt_len, u_char flags _U_) 391 { 392 if (opt_len != 12) 393 return 0; 394 395 ND_PRINT((ndo, " key 0x%" PRIx64, EXTRACT_64BITS(opt + 4))); 396 return 1; 397 } 398 399 static const struct { 400 const char *name; 401 int (*print)(netdissect_options *, const u_char *, u_int, u_char); 402 } mptcp_options[] = { 403 { "capable", mp_capable_print}, 404 { "join", mp_join_print }, 405 { "dss", mp_dss_print }, 406 { "add-addr", add_addr_print }, 407 { "rem-addr", remove_addr_print }, 408 { "prio", mp_prio_print }, 409 { "fail", mp_fail_print }, 410 { "fast-close", mp_fast_close_print }, 411 { "unknown", dummy_print }, 412 }; 413 414 int 415 mptcp_print(netdissect_options *ndo, 416 const u_char *cp, u_int len, u_char flags) 417 { 418 struct mptcp_option *opt; 419 u_int subtype; 420 421 if (len < 3) 422 return 0; 423 424 opt = (struct mptcp_option *) cp; 425 subtype = min(MPTCP_OPT_SUBTYPE(opt->sub_etc), MPTCP_SUB_FCLOSE + 1); 426 427 ND_PRINT((ndo, " %s", mptcp_options[subtype].name)); 428 return mptcp_options[subtype].print(ndo, cp, len, flags); 429 } 430
