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 #ifdef HAVE_CONFIG_H
  31 #include "config.h"
  32 #endif
  33
  34 #include <netdissect-stdinc.h>
  35
  36 #include "ip6.h"
  37 #include "netdissect.h"
  38 #include "addrtoname.h"
  39 #include "extract.h"
  40
  41 /* Mobility header */
  42 struct ip6_mobility {
  43         uint8_t ip6m_pproto;    /* following payload protocol (for PG) */
  44         uint8_t ip6m_len;       /* length in units of 8 octets */
  45         uint8_t ip6m_type;      /* message type */
  46         uint8_t reserved;       /* reserved */
  47         uint16_t ip6m_cksum;    /* sum of IPv6 pseudo-header and MH */
  48         union {
  49                 uint16_t        ip6m_un_data16[1]; /* type-specific field */
  50                 uint8_t         ip6m_un_data8[2];  /* type-specific field */
  51         } ip6m_dataun;
  52 };
  53
  54 #define ip6m_data16     ip6m_dataun.ip6m_un_data16
  55 #define ip6m_data8      ip6m_dataun.ip6m_un_data8
  56
  57 #define IP6M_MINLEN     8
  58
  59 /* http://www.iana.org/assignments/mobility-parameters/mobility-parameters.xhtml */
  60
  61 /* message type */
  62 #define IP6M_BINDING_REQUEST    0       /* Binding Refresh Request */
  63 #define IP6M_HOME_TEST_INIT     1       /* Home Test Init */
  64 #define IP6M_CAREOF_TEST_INIT   2       /* Care-of Test Init */
  65 #define IP6M_HOME_TEST          3       /* Home Test */
  66 #define IP6M_CAREOF_TEST        4       /* Care-of Test */
  67 #define IP6M_BINDING_UPDATE     5       /* Binding Update */
  68 #define IP6M_BINDING_ACK        6       /* Binding Acknowledgement */
  69 #define IP6M_BINDING_ERROR      7       /* Binding Error */
  70 #define IP6M_MAX                7
  71
  72 static const struct tok ip6m_str[] = {
  73         { IP6M_BINDING_REQUEST,  "BRR"  },
  74         { IP6M_HOME_TEST_INIT,   "HoTI" },
  75         { IP6M_CAREOF_TEST_INIT, "CoTI" },
  76         { IP6M_HOME_TEST,        "HoT"  },
  77         { IP6M_CAREOF_TEST,      "CoT"  },
  78         { IP6M_BINDING_UPDATE,   "BU"   },
  79         { IP6M_BINDING_ACK,      "BA"   },
  80         { IP6M_BINDING_ERROR,    "BE"   },
  81         { 0, NULL }
  82 };
  83
  84 static const unsigned ip6m_hdrlen[IP6M_MAX + 1] = {
  85         IP6M_MINLEN,      /* IP6M_BINDING_REQUEST  */
  86         IP6M_MINLEN + 8,  /* IP6M_HOME_TEST_INIT   */
  87         IP6M_MINLEN + 8,  /* IP6M_CAREOF_TEST_INIT */
  88         IP6M_MINLEN + 16, /* IP6M_HOME_TEST        */
  89         IP6M_MINLEN + 16, /* IP6M_CAREOF_TEST      */
  90         IP6M_MINLEN + 4,  /* IP6M_BINDING_UPDATE   */
  91         IP6M_MINLEN + 4,  /* IP6M_BINDING_ACK      */
  92         IP6M_MINLEN + 16, /* IP6M_BINDING_ERROR    */
  93 };
  94
  95 /* Mobility Header Options */
  96 #define IP6MOPT_MINLEN          2
  97 #define IP6MOPT_PAD1          0x0       /* Pad1 */
  98 #define IP6MOPT_PADN          0x1       /* PadN */
  99 #define IP6MOPT_REFRESH       0x2       /* Binding Refresh Advice */
 100 #define IP6MOPT_REFRESH_MINLEN  4
 101 #define IP6MOPT_ALTCOA        0x3       /* Alternate Care-of Address */
 102 #define IP6MOPT_ALTCOA_MINLEN  18
 103 #define IP6MOPT_NONCEID       0x4       /* Nonce Indices */
 104 #define IP6MOPT_NONCEID_MINLEN  6
 105 #define IP6MOPT_AUTH          0x5       /* Binding Authorization Data */
 106 #define IP6MOPT_AUTH_MINLEN    12
 107
 108 static void
 109 mobility_opt_print(netdissect_options *ndo,
 110                    const u_char *bp, const unsigned len)
 111 {
 112         unsigned i, optlen;
 113
 114         for (i = 0; i < len; i += optlen) {
 115                 ND_TCHECK(bp[i]);
 116                 if (bp[i] == IP6MOPT_PAD1)
 117                         optlen = 1;
 118                 else {
 119                         if (i + 1 < len) {
 120                                 ND_TCHECK(bp[i + 1]);
 121                                 optlen = bp[i + 1] + 2;
 122                         }
 123                         else
 124                                 goto trunc;
 125                 }
 126                 if (i + optlen > len)
 127                         goto trunc;
 128                 ND_TCHECK(bp[i + optlen]);
 129
 130                 switch (bp[i]) {
 131                 case IP6MOPT_PAD1:
 132                         ND_PRINT((ndo, "(pad1)"));
 133                         break;
 134                 case IP6MOPT_PADN:
 135                         if (len - i < IP6MOPT_MINLEN) {
 136                                 ND_PRINT((ndo, "(padn: trunc)"));
 137                                 goto trunc;
 138                         }
 139                         ND_PRINT((ndo, "(padn)"));
 140                         break;
 141                 case IP6MOPT_REFRESH:
 142                         if (len - i < IP6MOPT_REFRESH_MINLEN) {
 143                                 ND_PRINT((ndo, "(refresh: trunc)"));
 144                                 goto trunc;
 145                         }
 146                         /* units of 4 secs */
 147                         ND_PRINT((ndo, "(refresh: %u)",
 148                                 EXTRACT_16BITS(&bp[i+2]) << 2));
 149                         break;
 150                 case IP6MOPT_ALTCOA:
 151                         if (len - i < IP6MOPT_ALTCOA_MINLEN) {
 152                                 ND_PRINT((ndo, "(altcoa: trunc)"));
 153                                 goto trunc;
 154                         }
 155                         ND_PRINT((ndo, "(alt-CoA: %s)", ip6addr_string(ndo, &bp[i+2])));
 156                         break;
 157                 case IP6MOPT_NONCEID:
 158                         if (len - i < IP6MOPT_NONCEID_MINLEN) {
 159                                 ND_PRINT((ndo, "(ni: trunc)"));
 160                                 goto trunc;
 161                         }
 162                         ND_PRINT((ndo, "(ni: ho=0x%04x co=0x%04x)",
 163                                 EXTRACT_16BITS(&bp[i+2]),
 164                                 EXTRACT_16BITS(&bp[i+4])));
 165                         break;
 166                 case IP6MOPT_AUTH:
 167                         if (len - i < IP6MOPT_AUTH_MINLEN) {
 168                                 ND_PRINT((ndo, "(auth: trunc)"));
 169                                 goto trunc;
 170                         }
 171                         ND_PRINT((ndo, "(auth)"));
 172                         break;
 173                 default:
 174                         if (len - i < IP6MOPT_MINLEN) {
 175                                 ND_PRINT((ndo, "(sopt_type %u: trunc)", bp[i]));
 176                                 goto trunc;
 177                         }
 178                         ND_PRINT((ndo, "(type-0x%02x: len=%u)", bp[i], bp[i + 1]));
 179                         break;
 180                 }
 181         }
 182         return;
 183
 184 trunc:
 185         ND_PRINT((ndo, "[trunc] "));
 186 }
 187
 188 /*
 189  * Mobility Header
 190  */
 191 int
 192 mobility_print(netdissect_options *ndo,
 193                const u_char *bp, const u_char *bp2 _U_)
 194 {
 195         const struct ip6_mobility *mh;
 196         const u_char *ep;
 197         unsigned mhlen, hlen;
 198         uint8_t type;
 199
 200         mh = (const struct ip6_mobility *)bp;
 201
 202         /* 'ep' points to the end of available data. */
 203         ep = ndo->ndo_snapend;
 204
 205         if (!ND_TTEST(mh->ip6m_len)) {
 206                 /*
 207                  * There's not enough captured data to include the
 208                  * mobility header length.
 209                  *
 210                  * Our caller expects us to return the length, however,
 211                  * so return a value that will run to the end of the
 212                  * captured data.
 213                  *
 214                  * XXX - "ip6_print()" doesn't do anything with the
 215                  * returned length, however, as it breaks out of the
 216                  * header-processing loop.
 217                  */
 218                 mhlen = ep - bp;
 219                 goto trunc;
 220         }
 221         mhlen = (mh->ip6m_len + 1) << 3;
 222
 223         /* XXX ip6m_cksum */
 224
 225         ND_TCHECK(mh->ip6m_type);
 226         type = mh->ip6m_type;
 227         if (type <= IP6M_MAX && mhlen < ip6m_hdrlen[type]) {
 228                 ND_PRINT((ndo, "(header length %u is too small for type %u)", mhlen, type));
 229                 goto trunc;
 230         }
 231         ND_PRINT((ndo, "mobility: %s", tok2str(ip6m_str, "type-#%u", type)));
 232         switch (type) {
 233         case IP6M_BINDING_REQUEST:
 234                 hlen = IP6M_MINLEN;
 235                 break;
 236         case IP6M_HOME_TEST_INIT:
 237         case IP6M_CAREOF_TEST_INIT:
 238                 hlen = IP6M_MINLEN;
 239                 if (ndo->ndo_vflag) {
 240                         ND_TCHECK2(*mh, hlen + 8);
 241                         ND_PRINT((ndo, " %s Init Cookie=%08x:%08x",
 242                                type == IP6M_HOME_TEST_INIT ? "Home" : "Care-of",
 243                                EXTRACT_32BITS(&bp[hlen]),
 244                                EXTRACT_32BITS(&bp[hlen + 4])));
 245                 }
 246                 hlen += 8;
 247                 break;
 248         case IP6M_HOME_TEST:
 249         case IP6M_CAREOF_TEST:
 250                 ND_TCHECK(mh->ip6m_data16[0]);
 251                 ND_PRINT((ndo, " nonce id=0x%x", EXTRACT_16BITS(&mh->ip6m_data16[0])));
 252                 hlen = IP6M_MINLEN;
 253                 if (ndo->ndo_vflag) {
 254                         ND_TCHECK2(*mh, hlen + 8);
 255                         ND_PRINT((ndo, " %s Init Cookie=%08x:%08x",
 256                                type == IP6M_HOME_TEST ? "Home" : "Care-of",
 257                                EXTRACT_32BITS(&bp[hlen]),
 258                                EXTRACT_32BITS(&bp[hlen + 4])));
 259                 }
 260                 hlen += 8;
 261                 if (ndo->ndo_vflag) {
 262                         ND_TCHECK2(*mh, hlen + 8);
 263                         ND_PRINT((ndo, " %s Keygen Token=%08x:%08x",
 264                                type == IP6M_HOME_TEST ? "Home" : "Care-of",
 265                                EXTRACT_32BITS(&bp[hlen]),
 266                                EXTRACT_32BITS(&bp[hlen + 4])));
 267                 }
 268                 hlen += 8;
 269                 break;
 270         case IP6M_BINDING_UPDATE:
 271                 ND_TCHECK(mh->ip6m_data16[0]);
 272                 ND_PRINT((ndo, " seq#=%u", EXTRACT_16BITS(&mh->ip6m_data16[0])));
 273                 hlen = IP6M_MINLEN;
 274                 ND_TCHECK2(*mh, hlen + 1);
 275                 if (bp[hlen] & 0xf0)
 276                         ND_PRINT((ndo, " "));
 277                 if (bp[hlen] & 0x80)
 278                         ND_PRINT((ndo, "A"));
 279                 if (bp[hlen] & 0x40)
 280                         ND_PRINT((ndo, "H"));
 281                 if (bp[hlen] & 0x20)
 282                         ND_PRINT((ndo, "L"));
 283                 if (bp[hlen] & 0x10)
 284                         ND_PRINT((ndo, "K"));
 285                 /* Reserved (4bits) */
 286                 hlen += 1;
 287                 /* Reserved (8bits) */
 288                 hlen += 1;
 289                 ND_TCHECK2(*mh, hlen + 2);
 290                 /* units of 4 secs */
 291                 ND_PRINT((ndo, " lifetime=%u", EXTRACT_16BITS(&bp[hlen]) << 2));
 292                 hlen += 2;
 293                 break;
 294         case IP6M_BINDING_ACK:
 295                 ND_TCHECK(mh->ip6m_data8[0]);
 296                 ND_PRINT((ndo, " status=%u", mh->ip6m_data8[0]));
 297                 if (mh->ip6m_data8[1] & 0x80)
 298                         ND_PRINT((ndo, " K"));
 299                 /* Reserved (7bits) */
 300                 hlen = IP6M_MINLEN;
 301                 ND_TCHECK2(*mh, hlen + 2);
 302                 ND_PRINT((ndo, " seq#=%u", EXTRACT_16BITS(&bp[hlen])));
 303                 hlen += 2;
 304                 ND_TCHECK2(*mh, hlen + 2);
 305                 /* units of 4 secs */
 306                 ND_PRINT((ndo, " lifetime=%u", EXTRACT_16BITS(&bp[hlen]) << 2));
 307                 hlen += 2;
 308                 break;
 309         case IP6M_BINDING_ERROR:
 310                 ND_TCHECK(mh->ip6m_data8[0]);
 311                 ND_PRINT((ndo, " status=%u", mh->ip6m_data8[0]));
 312                 /* Reserved */
 313                 hlen = IP6M_MINLEN;
 314                 ND_TCHECK2(*mh, hlen + 16);
 315                 ND_PRINT((ndo, " homeaddr %s", ip6addr_string(ndo, &bp[hlen])));
 316                 hlen += 16;
 317                 break;
 318         default:
 319                 ND_PRINT((ndo, " len=%u", mh->ip6m_len));
 320                 return(mhlen);
 321                 break;
 322         }
 323         if (ndo->ndo_vflag)
 324                 mobility_opt_print(ndo, &bp[hlen], mhlen - hlen);
 325
 326         return(mhlen);
 327
 328  trunc:
 329         ND_PRINT((ndo, "[|MOBILITY]"));
 330         return(mhlen);
 331 }