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 "netdissect.h"
  40 #include "addrtoname.h"
  41 #include "extract.h"
  42
  43 #include "ip6.h"
  44
  45 static const char tstr[] = "[|MOBILITY]";
  46
  47 /* Mobility header */
  48 struct ip6_mobility {
  49         uint8_t ip6m_pproto;    /* following payload protocol (for PG) */
  50         uint8_t ip6m_len;       /* length in units of 8 octets */
  51         uint8_t ip6m_type;      /* message type */
  52         uint8_t reserved;       /* reserved */
  53         uint16_t ip6m_cksum;    /* sum of IPv6 pseudo-header and MH */
  54         union {
  55                 uint16_t        ip6m_un_data16[1]; /* type-specific field */
  56                 uint8_t         ip6m_un_data8[2];  /* type-specific field */
  57         } ip6m_dataun;
  58 };
  59
  60 #define ip6m_data16     ip6m_dataun.ip6m_un_data16
  61 #define ip6m_data8      ip6m_dataun.ip6m_un_data8
  62
  63 #define IP6M_MINLEN     8
  64
  65 /* http://www.iana.org/assignments/mobility-parameters/mobility-parameters.xhtml */
  66
  67 /* message type */
  68 #define IP6M_BINDING_REQUEST    0       /* Binding Refresh Request */
  69 #define IP6M_HOME_TEST_INIT     1       /* Home Test Init */
  70 #define IP6M_CAREOF_TEST_INIT   2       /* Care-of Test Init */
  71 #define IP6M_HOME_TEST          3       /* Home Test */
  72 #define IP6M_CAREOF_TEST        4       /* Care-of Test */
  73 #define IP6M_BINDING_UPDATE     5       /* Binding Update */
  74 #define IP6M_BINDING_ACK        6       /* Binding Acknowledgement */
  75 #define IP6M_BINDING_ERROR      7       /* Binding Error */
  76 #define IP6M_MAX                7
  77
  78 static const struct tok ip6m_str[] = {
  79         { IP6M_BINDING_REQUEST,  "BRR"  },
  80         { IP6M_HOME_TEST_INIT,   "HoTI" },
  81         { IP6M_CAREOF_TEST_INIT, "CoTI" },
  82         { IP6M_HOME_TEST,        "HoT"  },
  83         { IP6M_CAREOF_TEST,      "CoT"  },
  84         { IP6M_BINDING_UPDATE,   "BU"   },
  85         { IP6M_BINDING_ACK,      "BA"   },
  86         { IP6M_BINDING_ERROR,    "BE"   },
  87         { 0, NULL }
  88 };
  89
  90 static const unsigned ip6m_hdrlen[IP6M_MAX + 1] = {
  91         IP6M_MINLEN,      /* IP6M_BINDING_REQUEST  */
  92         IP6M_MINLEN + 8,  /* IP6M_HOME_TEST_INIT   */
  93         IP6M_MINLEN + 8,  /* IP6M_CAREOF_TEST_INIT */
  94         IP6M_MINLEN + 16, /* IP6M_HOME_TEST        */
  95         IP6M_MINLEN + 16, /* IP6M_CAREOF_TEST      */
  96         IP6M_MINLEN + 4,  /* IP6M_BINDING_UPDATE   */
  97         IP6M_MINLEN + 4,  /* IP6M_BINDING_ACK      */
  98         IP6M_MINLEN + 16, /* IP6M_BINDING_ERROR    */
  99 };
 100
 101 /* Mobility Header Options */
 102 #define IP6MOPT_MINLEN          2
 103 #define IP6MOPT_PAD1          0x0       /* Pad1 */
 104 #define IP6MOPT_PADN          0x1       /* PadN */
 105 #define IP6MOPT_REFRESH       0x2       /* Binding Refresh Advice */
 106 #define IP6MOPT_REFRESH_MINLEN  4
 107 #define IP6MOPT_ALTCOA        0x3       /* Alternate Care-of Address */
 108 #define IP6MOPT_ALTCOA_MINLEN  18
 109 #define IP6MOPT_NONCEID       0x4       /* Nonce Indices */
 110 #define IP6MOPT_NONCEID_MINLEN  6
 111 #define IP6MOPT_AUTH          0x5       /* Binding Authorization Data */
 112 #define IP6MOPT_AUTH_MINLEN    12
 113
 114 static int
 115 mobility_opt_print(netdissect_options *ndo,
 116                    const u_char *bp, const unsigned len)
 117 {
 118         unsigned i, optlen;
 119
 120         for (i = 0; i < len; i += optlen) {
 121                 ND_TCHECK(bp[i]);
 122                 if (bp[i] == IP6MOPT_PAD1)
 123                         optlen = 1;
 124                 else {
 125                         if (i + 1 < len) {
 126                                 ND_TCHECK(bp[i + 1]);
 127                                 optlen = bp[i + 1] + 2;
 128                         }
 129                         else
 130                                 goto trunc;
 131                 }
 132                 if (i + optlen > len)
 133                         goto trunc;
 134                 ND_TCHECK(bp[i + optlen]);
 135
 136                 switch (bp[i]) {
 137                 case IP6MOPT_PAD1:
 138                         ND_PRINT((ndo, "(pad1)"));
 139                         break;
 140                 case IP6MOPT_PADN:
 141                         if (len - i < IP6MOPT_MINLEN) {
 142                                 ND_PRINT((ndo, "(padn: trunc)"));
 143                                 goto trunc;
 144                         }
 145                         ND_PRINT((ndo, "(padn)"));
 146                         break;
 147                 case IP6MOPT_REFRESH:
 148                         if (len - i < IP6MOPT_REFRESH_MINLEN) {
 149                                 ND_PRINT((ndo, "(refresh: trunc)"));
 150                                 goto trunc;
 151                         }
 152                         /* units of 4 secs */
 153                         ND_PRINT((ndo, "(refresh: %u)",
 154                                 EXTRACT_16BITS(&bp[i+2]) << 2));
 155                         break;
 156                 case IP6MOPT_ALTCOA:
 157                         if (len - i < IP6MOPT_ALTCOA_MINLEN) {
 158                                 ND_PRINT((ndo, "(altcoa: trunc)"));
 159                                 goto trunc;
 160                         }
 161                         ND_PRINT((ndo, "(alt-CoA: %s)", ip6addr_string(ndo, &bp[i+2])));
 162                         break;
 163                 case IP6MOPT_NONCEID:
 164                         if (len - i < IP6MOPT_NONCEID_MINLEN) {
 165                                 ND_PRINT((ndo, "(ni: trunc)"));
 166                                 goto trunc;
 167                         }
 168                         ND_PRINT((ndo, "(ni: ho=0x%04x co=0x%04x)",
 169                                 EXTRACT_16BITS(&bp[i+2]),
 170                                 EXTRACT_16BITS(&bp[i+4])));
 171                         break;
 172                 case IP6MOPT_AUTH:
 173                         if (len - i < IP6MOPT_AUTH_MINLEN) {
 174                                 ND_PRINT((ndo, "(auth: trunc)"));
 175                                 goto trunc;
 176                         }
 177                         ND_PRINT((ndo, "(auth)"));
 178                         break;
 179                 default:
 180                         if (len - i < IP6MOPT_MINLEN) {
 181                                 ND_PRINT((ndo, "(sopt_type %u: trunc)", bp[i]));
 182                                 goto trunc;
 183                         }
 184                         ND_PRINT((ndo, "(type-0x%02x: len=%u)", bp[i], bp[i + 1]));
 185                         break;
 186                 }
 187         }
 188         return 0;
 189
 190 trunc:
 191         return 1;
 192 }
 193
 194 /*
 195  * Mobility Header
 196  */
 197 int
 198 mobility_print(netdissect_options *ndo,
 199                const u_char *bp, const u_char *bp2 _U_)
 200 {
 201         const struct ip6_mobility *mh;
 202         const u_char *ep;
 203         unsigned mhlen, hlen;
 204         uint8_t type;
 205
 206         mh = (const struct ip6_mobility *)bp;
 207
 208         /* 'ep' points to the end of available data. */
 209         ep = ndo->ndo_snapend;
 210
 211         if (!ND_TTEST(mh->ip6m_len)) {
 212                 /*
 213                  * There's not enough captured data to include the
 214                  * mobility header length.
 215                  *
 216                  * Our caller expects us to return the length, however,
 217                  * so return a value that will run to the end of the
 218                  * captured data.
 219                  *
 220                  * XXX - "ip6_print()" doesn't do anything with the
 221                  * returned length, however, as it breaks out of the
 222                  * header-processing loop.
 223                  */
 224                 mhlen = ep - bp;
 225                 goto trunc;
 226         }
 227         mhlen = (mh->ip6m_len + 1) << 3;
 228
 229         /* XXX ip6m_cksum */
 230
 231         ND_TCHECK(mh->ip6m_type);
 232         type = mh->ip6m_type;
 233         if (type <= IP6M_MAX && mhlen < ip6m_hdrlen[type]) {
 234                 ND_PRINT((ndo, "(header length %u is too small for type %u)", mhlen, type));
 235                 goto trunc;
 236         }
 237         ND_PRINT((ndo, "mobility: %s", tok2str(ip6m_str, "type-#%u", type)));
 238         switch (type) {
 239         case IP6M_BINDING_REQUEST:
 240                 hlen = IP6M_MINLEN;
 241                 break;
 242         case IP6M_HOME_TEST_INIT:
 243         case IP6M_CAREOF_TEST_INIT:
 244                 hlen = IP6M_MINLEN;
 245                 if (ndo->ndo_vflag) {
 246                         ND_TCHECK_32BITS(&bp[hlen + 4]);
 247                         ND_PRINT((ndo, " %s Init Cookie=%08x:%08x",
 248                                type == IP6M_HOME_TEST_INIT ? "Home" : "Care-of",
 249                                EXTRACT_32BITS(&bp[hlen]),
 250                                EXTRACT_32BITS(&bp[hlen + 4])));
 251                 }
 252                 hlen += 8;
 253                 break;
 254         case IP6M_HOME_TEST:
 255         case IP6M_CAREOF_TEST:
 256                 ND_TCHECK(mh->ip6m_data16[0]);
 257                 ND_PRINT((ndo, " nonce id=0x%x", EXTRACT_16BITS(&mh->ip6m_data16[0])));
 258                 hlen = IP6M_MINLEN;
 259                 if (ndo->ndo_vflag) {
 260                         ND_TCHECK_32BITS(&bp[hlen + 4]);
 261                         ND_PRINT((ndo, " %s Init Cookie=%08x:%08x",
 262                                type == IP6M_HOME_TEST ? "Home" : "Care-of",
 263                                EXTRACT_32BITS(&bp[hlen]),
 264                                EXTRACT_32BITS(&bp[hlen + 4])));
 265                 }
 266                 hlen += 8;
 267                 if (ndo->ndo_vflag) {
 268                         ND_TCHECK_32BITS(&bp[hlen + 4]);
 269                         ND_PRINT((ndo, " %s Keygen Token=%08x:%08x",
 270                                type == IP6M_HOME_TEST ? "Home" : "Care-of",
 271                                EXTRACT_32BITS(&bp[hlen]),
 272                                EXTRACT_32BITS(&bp[hlen + 4])));
 273                 }
 274                 hlen += 8;
 275                 break;
 276         case IP6M_BINDING_UPDATE:
 277                 ND_TCHECK(mh->ip6m_data16[0]);
 278                 ND_PRINT((ndo, " seq#=%u", EXTRACT_16BITS(&mh->ip6m_data16[0])));
 279                 hlen = IP6M_MINLEN;
 280                 ND_TCHECK_16BITS(&bp[hlen]);
 281                 if (bp[hlen] & 0xf0) {
 282                         ND_PRINT((ndo, " "));
 283                         if (bp[hlen] & 0x80)
 284                                 ND_PRINT((ndo, "A"));
 285                         if (bp[hlen] & 0x40)
 286                                 ND_PRINT((ndo, "H"));
 287                         if (bp[hlen] & 0x20)
 288                                 ND_PRINT((ndo, "L"));
 289                         if (bp[hlen] & 0x10)
 290                                 ND_PRINT((ndo, "K"));
 291                 }
 292                 /* Reserved (4bits) */
 293                 hlen += 1;
 294                 /* Reserved (8bits) */
 295                 hlen += 1;
 296                 ND_TCHECK_16BITS(&bp[hlen]);
 297                 /* units of 4 secs */
 298                 ND_PRINT((ndo, " lifetime=%u", EXTRACT_16BITS(&bp[hlen]) << 2));
 299                 hlen += 2;
 300                 break;
 301         case IP6M_BINDING_ACK:
 302                 ND_TCHECK(mh->ip6m_data8[0]);
 303                 ND_PRINT((ndo, " status=%u", mh->ip6m_data8[0]));
 304                 ND_TCHECK(mh->ip6m_data8[1]);
 305                 if (mh->ip6m_data8[1] & 0x80)
 306                         ND_PRINT((ndo, " K"));
 307                 /* Reserved (7bits) */
 308                 hlen = IP6M_MINLEN;
 309                 ND_TCHECK_16BITS(&bp[hlen]);
 310                 ND_PRINT((ndo, " seq#=%u", EXTRACT_16BITS(&bp[hlen])));
 311                 hlen += 2;
 312                 ND_TCHECK_16BITS(&bp[hlen]);
 313                 /* units of 4 secs */
 314                 ND_PRINT((ndo, " lifetime=%u", EXTRACT_16BITS(&bp[hlen]) << 2));
 315                 hlen += 2;
 316                 break;
 317         case IP6M_BINDING_ERROR:
 318                 ND_TCHECK(mh->ip6m_data8[0]);
 319                 ND_PRINT((ndo, " status=%u", mh->ip6m_data8[0]));
 320                 /* Reserved */
 321                 hlen = IP6M_MINLEN;
 322                 ND_TCHECK2(bp[hlen], 16);
 323                 ND_PRINT((ndo, " homeaddr %s", ip6addr_string(ndo, &bp[hlen])));
 324                 hlen += 16;
 325                 break;
 326         default:
 327                 ND_PRINT((ndo, " len=%u", mh->ip6m_len));
 328                 return(mhlen);
 329                 break;
 330         }
 331         if (ndo->ndo_vflag)
 332                 if (mobility_opt_print(ndo, &bp[hlen], mhlen - hlen))
 333                         goto trunc;
 334
 335         return(mhlen);
 336
 337  trunc:
 338         ND_PRINT((ndo, "%s", tstr));
 339         return(-1);
 340 }