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 #ifdef HAVE_CONFIG_H 36 #include "config.h" 37 #endif 38 39 #include <tcpdump-stdinc.h> 40 41 #include <stdio.h> 42 #include <string.h> 43 44 #include "interface.h" 45 #include "extract.h" 46 #include "addrtoname.h" 47 48 #include "ipproto.h" 49 #include "mptcp.h" 50 #include "tcp.h" 51 52 static int dummy_print(const u_char *opt _U_, u_int opt_len _U_, u_char flags _U_) 53 { 54 return 1; 55 } 56 57 static int mp_capable_print(const u_char *opt, u_int opt_len, u_char flags) 58 { 59 struct mp_capable *mpc = (struct mp_capable *) opt; 60 61 if (!(opt_len == 12 && flags & TH_SYN) && 62 !(opt_len == 20 && (flags & (TH_SYN | TH_ACK)) == TH_ACK)) 63 return 0; 64 65 if (MP_CAPABLE_OPT_VERSION(mpc->sub_ver) != 0) { 66 printf(" Unknown Version (%d)", MP_CAPABLE_OPT_VERSION(mpc->sub_ver)); 67 return 1; 68 } 69 70 if (mpc->flags & MP_CAPABLE_C) 71 printf(" csum"); 72 printf(" {0x%" PRIx64, EXTRACT_64BITS(mpc->sender_key)); 73 if (opt_len == 20) /* ACK */ 74 printf(",0x%" PRIx64, EXTRACT_64BITS(mpc->receiver_key)); 75 printf("}"); 76 return 1; 77 } 78 79 static int mp_join_print(const u_char *opt, u_int opt_len, u_char flags) 80 { 81 struct mp_join *mpj = (struct mp_join *) opt; 82 83 if (!(opt_len == 12 && flags & TH_SYN) && 84 !(opt_len == 16 && (flags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK)) && 85 !(opt_len == 24 && flags & TH_ACK)) 86 return 0; 87 88 if (opt_len != 24) { 89 if (mpj->sub_b & MP_JOIN_B) 90 printf(" backup"); 91 printf(" id %u", mpj->addr_id); 92 } 93 94 switch (opt_len) { 95 case 12: /* SYN */ 96 printf(" token 0x%x" " nonce 0x%x", 97 EXTRACT_32BITS(mpj->u.syn.token), 98 EXTRACT_32BITS(mpj->u.syn.nonce)); 99 break; 100 case 16: /* SYN/ACK */ 101 printf(" hmac 0x%" PRIx64 " nonce 0x%x", 102 EXTRACT_64BITS(mpj->u.synack.mac), 103 EXTRACT_32BITS(mpj->u.synack.nonce)); 104 break; 105 case 24: {/* ACK */ 106 size_t i; 107 printf(" hmac 0x"); 108 for (i = 0; i < sizeof(mpj->u.ack.mac); ++i) 109 printf("%02x", mpj->u.ack.mac[i]); 110 } 111 default: 112 break; 113 } 114 return 1; 115 } 116 117 static u_int mp_dss_len(struct mp_dss *m, int csum) 118 { 119 u_int len; 120 121 len = 4; 122 if (m->flags & MP_DSS_A) { 123 /* Ack present - 4 or 8 octets */ 124 len += (m->flags & MP_DSS_a) ? 8 : 4; 125 } 126 if (m->flags & MP_DSS_M) { 127 /* 128 * Data Sequence Number (DSN), Subflow Sequence Number (SSN), 129 * Data-Level Length present, and Checksum possibly present. 130 * All but the Checksum are 10 bytes if the m flag is 131 * clear (4-byte DSN) and 14 bytes if the m flag is set 132 * (8-byte DSN). 133 */ 134 len += (m->flags & MP_DSS_m) ? 14 : 10; 135 136 /* 137 * The Checksum is present only if negotiated. 138 */ 139 if (csum) 140 len += 2; 141 } 142 return len; 143 } 144 145 static int mp_dss_print(const u_char *opt, u_int opt_len, u_char flags) 146 { 147 struct mp_dss *mdss = (struct mp_dss *) opt; 148 149 if ((opt_len != mp_dss_len(mdss, 1) && 150 opt_len != mp_dss_len(mdss, 0)) || flags & TH_SYN) 151 return 0; 152 153 if (mdss->flags & MP_DSS_F) 154 printf(" fin"); 155 156 opt += 4; 157 if (mdss->flags & MP_DSS_A) { 158 printf(" ack "); 159 if (mdss->flags & MP_DSS_a) { 160 printf("%" PRIu64, EXTRACT_64BITS(opt)); 161 opt += 8; 162 } else { 163 printf("%u", EXTRACT_32BITS(opt)); 164 opt += 4; 165 } 166 } 167 168 if (mdss->flags & MP_DSS_M) { 169 printf(" seq "); 170 if (mdss->flags & MP_DSS_m) { 171 printf("%" PRIu64, EXTRACT_64BITS(opt)); 172 opt += 8; 173 } else { 174 printf("%u", EXTRACT_32BITS(opt)); 175 opt += 4; 176 } 177 printf(" subseq %u", EXTRACT_32BITS(opt)); 178 opt += 4; 179 printf(" len %u", EXTRACT_16BITS(opt)); 180 opt += 2; 181 182 if (opt_len == mp_dss_len(mdss, 1)) 183 printf(" csum 0x%x", EXTRACT_16BITS(opt)); 184 } 185 return 1; 186 } 187 188 static int add_addr_print(const u_char *opt, u_int opt_len, u_char flags _U_) 189 { 190 struct mp_add_addr *add_addr = (struct mp_add_addr *) opt; 191 u_int ipver = MP_ADD_ADDR_IPVER(add_addr->sub_ipver); 192 193 if (!((opt_len == 8 || opt_len == 10) && ipver == 4) && 194 !((opt_len == 20 || opt_len == 22) && ipver == 6)) 195 return 0; 196 197 printf(" id %u", add_addr->addr_id); 198 switch (ipver) { 199 case 4: 200 printf(" %s", ipaddr_string(add_addr->u.v4.addr)); 201 if (opt_len == 10) 202 printf(":%u", EXTRACT_16BITS(add_addr->u.v4.port)); 203 break; 204 case 6: 205 #ifdef INET6 206 printf(" %s", ip6addr_string(add_addr->u.v6.addr)); 207 #endif 208 if (opt_len == 22) 209 printf(":%u", EXTRACT_16BITS(add_addr->u.v6.port)); 210 break; 211 default: 212 return 0; 213 } 214 215 return 1; 216 } 217 218 static int remove_addr_print(const u_char *opt, u_int opt_len, u_char flags _U_) 219 { 220 struct mp_remove_addr *remove_addr = (struct mp_remove_addr *) opt; 221 u_int8_t *addr_id = &remove_addr->addrs_id; 222 223 if (opt_len < 4) 224 return 0; 225 226 opt_len -= 3; 227 printf(" id"); 228 while (opt_len--) 229 printf(" %u", *addr_id++); 230 return 1; 231 } 232 233 static int mp_prio_print(const u_char *opt, u_int opt_len, u_char flags _U_) 234 { 235 struct mp_prio *mpp = (struct mp_prio *) opt; 236 237 if (opt_len != 3 && opt_len != 4) 238 return 0; 239 240 if (mpp->sub_b & MP_PRIO_B) 241 printf(" backup"); 242 else 243 printf(" non-backup"); 244 if (opt_len == 4) 245 printf(" id %u", mpp->addr_id); 246 247 return 1; 248 } 249 250 static int mp_fail_print(const u_char *opt, u_int opt_len, u_char flags _U_) 251 { 252 if (opt_len != 12) 253 return 0; 254 255 printf(" seq %" PRIu64, EXTRACT_64BITS(opt + 4)); 256 return 1; 257 } 258 259 static int mp_fast_close_print(const u_char *opt, u_int opt_len, u_char flags _U_) 260 { 261 if (opt_len != 12) 262 return 0; 263 264 printf(" key 0x%" PRIx64, EXTRACT_64BITS(opt + 4)); 265 return 1; 266 } 267 268 static struct { 269 const char *name; 270 int (*print)(const u_char *, u_int, u_char); 271 } mptcp_options[] = { 272 { "capable", mp_capable_print}, 273 { "join", mp_join_print }, 274 { "dss", mp_dss_print }, 275 { "add-addr", add_addr_print }, 276 { "rem-addr", remove_addr_print }, 277 { "prio", mp_prio_print }, 278 { "fail", mp_fail_print }, 279 { "fast-close", mp_fast_close_print }, 280 { "unknown", dummy_print }, 281 }; 282 283 int mptcp_print(const u_char *cp, u_int len, u_char flags) 284 { 285 struct mptcp_option *opt; 286 u_int subtype; 287 288 if (len < 3) 289 return 0; 290 291 opt = (struct mptcp_option *) cp; 292 subtype = min(MPTCP_OPT_SUBTYPE(opt->sub_etc), MPTCP_SUB_FCLOSE + 1); 293 294 printf(" %s", mptcp_options[subtype].name); 295 return mptcp_options[subtype].print(cp, len, flags); 296 } 297
