The Tcpdump Group git mirrors - tcpdump/blob - print-mobility.c

   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 #ifdef HAVE_CONFIG_H
  34 #include "config.h"
  35 #endif
  36
  37 #include <netdissect-stdinc.h>
  38
  39 #include "ip6.h"
  40 #include "netdissect.h"
  41 #include "addrtoname.h"
  42 #include "extract.h"
  43
  44 static const char tstr[] = "[|MOBILITY]";
  45
  46 /* Mobility header */
  47 struct ip6_mobility {
  48         uint8_t ip6m_pproto;    /* following payload protocol (for PG) */
  49         uint8_t ip6m_len;       /* length in units of 8 octets */
  50         uint8_t ip6m_type;      /* message type */
  51         uint8_t reserved;       /* reserved */
  52         uint16_t ip6m_cksum;    /* sum of IPv6 pseudo-header and MH */
  53         union {
  54                 uint16_t        ip6m_un_data16[1]; /* type-specific field */
  55                 uint8_t         ip6m_un_data8[2];  /* type-specific field */
  56         } ip6m_dataun;
  57 };
  58
  59 #define ip6m_data16     ip6m_dataun.ip6m_un_data16
  60 #define ip6m_data8      ip6m_dataun.ip6m_un_data8
  61
  62 #define IP6M_MINLEN     8
  63
  64 /* http://www.iana.org/assignments/mobility-parameters/mobility-parameters.xhtml */
  65
  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
  76
  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 };
  88
  89 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 };
  99
 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,
 115                    const u_char *bp, const unsigned len)
 116 {
 117         unsigned i, optlen;
 118
 119         for (i = 0; i < len; i += optlen) {
 120                 ND_TCHECK(bp[i]);
 121                 if (bp[i] == IP6MOPT_PAD1)
 122                         optlen = 1;
 123                 else {
 124                         if (i + 1 < len) {
 125                                 ND_TCHECK(bp[i + 1]);
 126                                 optlen = bp[i + 1] + 2;
 127                         }
 128                         else
 129                                 goto trunc;
 130                 }
 131                 if (i + optlen > len)
 132                         goto trunc;
 133                 ND_TCHECK(bp[i + optlen]);
 134
 135                 switch (bp[i]) {
 136                 case IP6MOPT_PAD1:
 137                         ND_PRINT((ndo, "(pad1)"));
 138                         break;
 139                 case IP6MOPT_PADN:
 140                         if (len - i < IP6MOPT_MINLEN) {
 141                                 ND_PRINT((ndo, "(padn: trunc)"));
 142                                 goto trunc;
 143                         }
 144                         ND_PRINT((ndo, "(padn)"));
 145                         break;
 146                 case IP6MOPT_REFRESH:
 147                         if (len - i < IP6MOPT_REFRESH_MINLEN) {
 148                                 ND_PRINT((ndo, "(refresh: trunc)"));
 149                                 goto trunc;
 150                         }
 151                         /* units of 4 secs */
 152                         ND_PRINT((ndo, "(refresh: %u)",
 153                                 EXTRACT_16BITS(&bp[i+2]) << 2));
 154                         break;
 155                 case IP6MOPT_ALTCOA:
 156                         if (len - i < IP6MOPT_ALTCOA_MINLEN) {
 157                                 ND_PRINT((ndo, "(altcoa: trunc)"));
 158                                 goto trunc;
 159                         }
 160                         ND_PRINT((ndo, "(alt-CoA: %s)", ip6addr_string(ndo, &bp[i+2])));
 161                         break;
 162                 case IP6MOPT_NONCEID:
 163                         if (len - i < IP6MOPT_NONCEID_MINLEN) {
 164                                 ND_PRINT((ndo, "(ni: trunc)"));
 165                                 goto trunc;
 166                         }
 167                         ND_PRINT((ndo, "(ni: ho=0x%04x co=0x%04x)",
 168                                 EXTRACT_16BITS(&bp[i+2]),
 169                                 EXTRACT_16BITS(&bp[i+4])));
 170                         break;
 171                 case IP6MOPT_AUTH:
 172                         if (len - i < IP6MOPT_AUTH_MINLEN) {
 173                                 ND_PRINT((ndo, "(auth: trunc)"));
 174                                 goto trunc;
 175                         }
 176                         ND_PRINT((ndo, "(auth)"));
 177                         break;
 178                 default:
 179                         if (len - i < IP6MOPT_MINLEN) {
 180                                 ND_PRINT((ndo, "(sopt_type %u: trunc)", bp[i]));
 181                                 goto trunc;
 182                         }
 183                         ND_PRINT((ndo, "(type-0x%02x: len=%u)", bp[i], bp[i + 1]));
 184                         break;
 185                 }
 186         }
 187         return 0;
 188
 189 trunc:
 190         return 1;
 191 }
 192
 193 /*
 194  * Mobility Header
 195  */
 196 int
 197 mobility_print(netdissect_options *ndo,
 198                const u_char *bp, const u_char *bp2 _U_)
 199 {
 200         const struct ip6_mobility *mh;
 201         const u_char *ep;
 202         unsigned mhlen, hlen;
 203         uint8_t type;
 204
 205         mh = (const struct ip6_mobility *)bp;
 206
 207         /* 'ep' points to the end of available data. */
 208         ep = ndo->ndo_snapend;
 209
 210         if (!ND_TTEST(mh->ip6m_len)) {
 211                 /*
 212                  * There's not enough captured data to include the
 213                  * mobility header length.
 214                  *
 215                  * Our caller expects us to return the length, however,
 216                  * so return a value that will run to the end of the
 217                  * captured data.
 218                  *
 219                  * XXX - "ip6_print()" doesn't do anything with the
 220                  * returned length, however, as it breaks out of the
 221                  * header-processing loop.
 222                  */
 223                 mhlen = ep - bp;
 224                 goto trunc;
 225         }
 226         mhlen = (mh->ip6m_len + 1) << 3;
 227
 228         /* XXX ip6m_cksum */
 229
 230         ND_TCHECK(mh->ip6m_type);
 231         type = mh->ip6m_type;
 232         if (type <= IP6M_MAX && mhlen < ip6m_hdrlen[type]) {
 233                 ND_PRINT((ndo, "(header length %u is too small for type %u)", mhlen, type));
 234                 goto trunc;
 235         }
 236         ND_PRINT((ndo, "mobility: %s", tok2str(ip6m_str, "type-#%u", type)));
 237         switch (type) {
 238         case IP6M_BINDING_REQUEST:
 239                 hlen = IP6M_MINLEN;
 240                 break;
 241         case IP6M_HOME_TEST_INIT:
 242         case IP6M_CAREOF_TEST_INIT:
 243                 hlen = IP6M_MINLEN;
 244                 if (ndo->ndo_vflag) {
 245                         ND_TCHECK_32BITS(&bp[hlen + 4]);
 246                         ND_PRINT((ndo, " %s Init Cookie=%08x:%08x",
 247                                type == IP6M_HOME_TEST_INIT ? "Home" : "Care-of",
 248                                EXTRACT_32BITS(&bp[hlen]),
 249                                EXTRACT_32BITS(&bp[hlen + 4])));
 250                 }
 251                 hlen += 8;
 252                 break;
 253         case IP6M_HOME_TEST:
 254         case IP6M_CAREOF_TEST:
 255                 ND_TCHECK(mh->ip6m_data16[0]);
 256                 ND_PRINT((ndo, " nonce id=0x%x", EXTRACT_16BITS(&mh->ip6m_data16[0])));
 257                 hlen = IP6M_MINLEN;
 258                 if (ndo->ndo_vflag) {
 259                         ND_TCHECK_32BITS(&bp[hlen + 4]);
 260                         ND_PRINT((ndo, " %s Init Cookie=%08x:%08x",
 261                                type == IP6M_HOME_TEST ? "Home" : "Care-of",
 262                                EXTRACT_32BITS(&bp[hlen]),
 263                                EXTRACT_32BITS(&bp[hlen + 4])));
 264                 }
 265                 hlen += 8;
 266                 if (ndo->ndo_vflag) {
 267                         ND_TCHECK_32BITS(&bp[hlen + 4]);
 268                         ND_PRINT((ndo, " %s Keygen Token=%08x:%08x",
 269                                type == IP6M_HOME_TEST ? "Home" : "Care-of",
 270                                EXTRACT_32BITS(&bp[hlen]),
 271                                EXTRACT_32BITS(&bp[hlen + 4])));
 272                 }
 273                 hlen += 8;
 274                 break;
 275         case IP6M_BINDING_UPDATE:
 276                 ND_TCHECK(mh->ip6m_data16[0]);
 277                 ND_PRINT((ndo, " seq#=%u", EXTRACT_16BITS(&mh->ip6m_data16[0])));
 278                 hlen = IP6M_MINLEN;
 279                 ND_TCHECK_16BITS(&bp[hlen]);
 280                 if (bp[hlen] & 0xf0) {
 281                         ND_PRINT((ndo, " "));
 282                         if (bp[hlen] & 0x80)
 283                                 ND_PRINT((ndo, "A"));
 284                         if (bp[hlen] & 0x40)
 285                                 ND_PRINT((ndo, "H"));
 286                         if (bp[hlen] & 0x20)
 287                                 ND_PRINT((ndo, "L"));
 288                         if (bp[hlen] & 0x10)
 289                                 ND_PRINT((ndo, "K"));
 290                 }
 291                 /* Reserved (4bits) */
 292                 hlen += 1;
 293                 /* Reserved (8bits) */
 294                 hlen += 1;
 295                 ND_TCHECK_16BITS(&bp[hlen]);
 296                 /* units of 4 secs */
 297                 ND_PRINT((ndo, " lifetime=%u", EXTRACT_16BITS(&bp[hlen]) << 2));
 298                 hlen += 2;
 299                 break;
 300         case IP6M_BINDING_ACK:
 301                 ND_TCHECK(mh->ip6m_data8[0]);
 302                 ND_PRINT((ndo, " status=%u", mh->ip6m_data8[0]));
 303                 ND_TCHECK(mh->ip6m_data8[1]);
 304                 if (mh->ip6m_data8[1] & 0x80)
 305                         ND_PRINT((ndo, " K"));
 306                 /* Reserved (7bits) */
 307                 hlen = IP6M_MINLEN;
 308                 ND_TCHECK_16BITS(&bp[hlen]);
 309                 ND_PRINT((ndo, " seq#=%u", EXTRACT_16BITS(&bp[hlen])));
 310                 hlen += 2;
 311                 ND_TCHECK_16BITS(&bp[hlen]);
 312                 /* units of 4 secs */
 313                 ND_PRINT((ndo, " lifetime=%u", EXTRACT_16BITS(&bp[hlen]) << 2));
 314                 hlen += 2;
 315                 break;
 316         case IP6M_BINDING_ERROR:
 317                 ND_TCHECK(mh->ip6m_data8[0]);
 318                 ND_PRINT((ndo, " status=%u", mh->ip6m_data8[0]));
 319                 /* Reserved */
 320                 hlen = IP6M_MINLEN;
 321                 ND_TCHECK2(bp[hlen], 16);
 322                 ND_PRINT((ndo, " homeaddr %s", ip6addr_string(ndo, &bp[hlen])));
 323                 hlen += 16;
 324                 break;
 325         default:
 326                 ND_PRINT((ndo, " len=%u", mh->ip6m_len));
 327                 return(mhlen);
 328                 break;
 329         }
 330         if (ndo->ndo_vflag)
 331                 if (mobility_opt_print(ndo, &bp[hlen], mhlen - hlen))
 332                         goto trunc;
 333
 334         return(mhlen);
 335
 336  trunc:
 337         ND_PRINT((ndo, "%s", tstr));
 338         return(-1);
 339 }