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
  32 #ifdef HAVE_CONFIG_H
  33 #include "config.h"
  34 #endif
  35
  36 #include <netdissect-stdinc.h>
  37
  38 #include "ip6.h"
  39 #include "netdissect.h"
  40 #include "addrtoname.h"
  41 #include "extract.h"
  42
  43 /* Mobility header */
  44 struct ip6_mobility {
  45         uint8_t ip6m_pproto;    /* following payload protocol (for PG) */
  46         uint8_t ip6m_len;       /* length in units of 8 octets */
  47         uint8_t ip6m_type;      /* message type */
  48         uint8_t reserved;       /* reserved */
  49         uint16_t ip6m_cksum;    /* sum of IPv6 pseudo-header and MH */
  50         union {
  51                 uint16_t        ip6m_un_data16[1]; /* type-specific field */
  52                 uint8_t         ip6m_un_data8[2];  /* type-specific field */
  53         } ip6m_dataun;
  54 };
  55
  56 #define ip6m_data16     ip6m_dataun.ip6m_un_data16
  57 #define ip6m_data8      ip6m_dataun.ip6m_un_data8
  58
  59 #define IP6M_MINLEN     8
  60
  61 /* http://www.iana.org/assignments/mobility-parameters/mobility-parameters.xhtml */
  62
  63 /* message type */
  64 #define IP6M_BINDING_REQUEST    0       /* Binding Refresh Request */
  65 #define IP6M_HOME_TEST_INIT     1       /* Home Test Init */
  66 #define IP6M_CAREOF_TEST_INIT   2       /* Care-of Test Init */
  67 #define IP6M_HOME_TEST          3       /* Home Test */
  68 #define IP6M_CAREOF_TEST        4       /* Care-of Test */
  69 #define IP6M_BINDING_UPDATE     5       /* Binding Update */
  70 #define IP6M_BINDING_ACK        6       /* Binding Acknowledgement */
  71 #define IP6M_BINDING_ERROR      7       /* Binding Error */
  72 #define IP6M_MAX                7
  73
  74 static const struct tok ip6m_str[] = {
  75         { IP6M_BINDING_REQUEST,  "BRR"  },
  76         { IP6M_HOME_TEST_INIT,   "HoTI" },
  77         { IP6M_CAREOF_TEST_INIT, "CoTI" },
  78         { IP6M_HOME_TEST,        "HoT"  },
  79         { IP6M_CAREOF_TEST,      "CoT"  },
  80         { IP6M_BINDING_UPDATE,   "BU"   },
  81         { IP6M_BINDING_ACK,      "BA"   },
  82         { IP6M_BINDING_ERROR,    "BE"   },
  83         { 0, NULL }
  84 };
  85
  86 static const unsigned ip6m_hdrlen[IP6M_MAX + 1] = {
  87         IP6M_MINLEN,      /* IP6M_BINDING_REQUEST  */
  88         IP6M_MINLEN + 8,  /* IP6M_HOME_TEST_INIT   */
  89         IP6M_MINLEN + 8,  /* IP6M_CAREOF_TEST_INIT */
  90         IP6M_MINLEN + 16, /* IP6M_HOME_TEST        */
  91         IP6M_MINLEN + 16, /* IP6M_CAREOF_TEST      */
  92         IP6M_MINLEN + 4,  /* IP6M_BINDING_UPDATE   */
  93         IP6M_MINLEN + 4,  /* IP6M_BINDING_ACK      */
  94         IP6M_MINLEN + 16, /* IP6M_BINDING_ERROR    */
  95 };
  96
  97 /* Mobility Header Options */
  98 #define IP6MOPT_MINLEN          2
  99 #define IP6MOPT_PAD1          0x0       /* Pad1 */
 100 #define IP6MOPT_PADN          0x1       /* PadN */
 101 #define IP6MOPT_REFRESH       0x2       /* Binding Refresh Advice */
 102 #define IP6MOPT_REFRESH_MINLEN  4
 103 #define IP6MOPT_ALTCOA        0x3       /* Alternate Care-of Address */
 104 #define IP6MOPT_ALTCOA_MINLEN  18
 105 #define IP6MOPT_NONCEID       0x4       /* Nonce Indices */
 106 #define IP6MOPT_NONCEID_MINLEN  6
 107 #define IP6MOPT_AUTH          0x5       /* Binding Authorization Data */
 108 #define IP6MOPT_AUTH_MINLEN    12
 109
 110 static void
 111 mobility_opt_print(netdissect_options *ndo,
 112                    const u_char *bp, const unsigned len)
 113 {
 114         unsigned i, optlen;
 115
 116         for (i = 0; i < len; i += optlen) {
 117                 ND_TCHECK(bp[i]);
 118                 if (bp[i] == IP6MOPT_PAD1)
 119                         optlen = 1;
 120                 else {
 121                         if (i + 1 < len) {
 122                                 ND_TCHECK(bp[i + 1]);
 123                                 optlen = bp[i + 1] + 2;
 124                         }
 125                         else
 126                                 goto trunc;
 127                 }
 128                 if (i + optlen > len)
 129                         goto trunc;
 130                 ND_TCHECK(bp[i + optlen]);
 131
 132                 switch (bp[i]) {
 133                 case IP6MOPT_PAD1:
 134                         ND_PRINT((ndo, "(pad1)"));
 135                         break;
 136                 case IP6MOPT_PADN:
 137                         if (len - i < IP6MOPT_MINLEN) {
 138                                 ND_PRINT((ndo, "(padn: trunc)"));
 139                                 goto trunc;
 140                         }
 141                         ND_PRINT((ndo, "(padn)"));
 142                         break;
 143                 case IP6MOPT_REFRESH:
 144                         if (len - i < IP6MOPT_REFRESH_MINLEN) {
 145                                 ND_PRINT((ndo, "(refresh: trunc)"));
 146                                 goto trunc;
 147                         }
 148                         /* units of 4 secs */
 149                         ND_PRINT((ndo, "(refresh: %u)",
 150                                 EXTRACT_16BITS(&bp[i+2]) << 2));
 151                         break;
 152                 case IP6MOPT_ALTCOA:
 153                         if (len - i < IP6MOPT_ALTCOA_MINLEN) {
 154                                 ND_PRINT((ndo, "(altcoa: trunc)"));
 155                                 goto trunc;
 156                         }
 157                         ND_PRINT((ndo, "(alt-CoA: %s)", ip6addr_string(ndo, &bp[i+2])));
 158                         break;
 159                 case IP6MOPT_NONCEID:
 160                         if (len - i < IP6MOPT_NONCEID_MINLEN) {
 161                                 ND_PRINT((ndo, "(ni: trunc)"));
 162                                 goto trunc;
 163                         }
 164                         ND_PRINT((ndo, "(ni: ho=0x%04x co=0x%04x)",
 165                                 EXTRACT_16BITS(&bp[i+2]),
 166                                 EXTRACT_16BITS(&bp[i+4])));
 167                         break;
 168                 case IP6MOPT_AUTH:
 169                         if (len - i < IP6MOPT_AUTH_MINLEN) {
 170                                 ND_PRINT((ndo, "(auth: trunc)"));
 171                                 goto trunc;
 172                         }
 173                         ND_PRINT((ndo, "(auth)"));
 174                         break;
 175                 default:
 176                         if (len - i < IP6MOPT_MINLEN) {
 177                                 ND_PRINT((ndo, "(sopt_type %u: trunc)", bp[i]));
 178                                 goto trunc;
 179                         }
 180                         ND_PRINT((ndo, "(type-0x%02x: len=%u)", bp[i], bp[i + 1]));
 181                         break;
 182                 }
 183         }
 184         return;
 185
 186 trunc:
 187         ND_PRINT((ndo, "[trunc] "));
 188 }
 189
 190 /*
 191  * Mobility Header
 192  */
 193 int
 194 mobility_print(netdissect_options *ndo,
 195                const u_char *bp, const u_char *bp2 _U_)
 196 {
 197         const struct ip6_mobility *mh;
 198         const u_char *ep;
 199         unsigned mhlen, hlen;
 200         uint8_t type;
 201
 202         mh = (const struct ip6_mobility *)bp;
 203
 204         /* 'ep' points to the end of available data. */
 205         ep = ndo->ndo_snapend;
 206
 207         if (!ND_TTEST(mh->ip6m_len)) {
 208                 /*
 209                  * There's not enough captured data to include the
 210                  * mobility header length.
 211                  *
 212                  * Our caller expects us to return the length, however,
 213                  * so return a value that will run to the end of the
 214                  * captured data.
 215                  *
 216                  * XXX - "ip6_print()" doesn't do anything with the
 217                  * returned length, however, as it breaks out of the
 218                  * header-processing loop.
 219                  */
 220                 mhlen = ep - bp;
 221                 goto trunc;
 222         }
 223         mhlen = (mh->ip6m_len + 1) << 3;
 224
 225         /* XXX ip6m_cksum */
 226
 227         ND_TCHECK(mh->ip6m_type);
 228         type = mh->ip6m_type;
 229         if (type <= IP6M_MAX && mhlen < ip6m_hdrlen[type]) {
 230                 ND_PRINT((ndo, "(header length %u is too small for type %u)", mhlen, type));
 231                 goto trunc;
 232         }
 233         ND_PRINT((ndo, "mobility: %s", tok2str(ip6m_str, "type-#%u", type)));
 234         switch (type) {
 235         case IP6M_BINDING_REQUEST:
 236                 hlen = IP6M_MINLEN;
 237                 break;
 238         case IP6M_HOME_TEST_INIT:
 239         case IP6M_CAREOF_TEST_INIT:
 240                 hlen = IP6M_MINLEN;
 241                 if (ndo->ndo_vflag) {
 242                         ND_TCHECK2(*mh, hlen + 8);
 243                         ND_PRINT((ndo, " %s Init Cookie=%08x:%08x",
 244                                type == IP6M_HOME_TEST_INIT ? "Home" : "Care-of",
 245                                EXTRACT_32BITS(&bp[hlen]),
 246                                EXTRACT_32BITS(&bp[hlen + 4])));
 247                 }
 248                 hlen += 8;
 249                 break;
 250         case IP6M_HOME_TEST:
 251         case IP6M_CAREOF_TEST:
 252                 ND_TCHECK(mh->ip6m_data16[0]);
 253                 ND_PRINT((ndo, " nonce id=0x%x", EXTRACT_16BITS(&mh->ip6m_data16[0])));
 254                 hlen = IP6M_MINLEN;
 255                 if (ndo->ndo_vflag) {
 256                         ND_TCHECK2(*mh, hlen + 8);
 257                         ND_PRINT((ndo, " %s Init Cookie=%08x:%08x",
 258                                type == IP6M_HOME_TEST ? "Home" : "Care-of",
 259                                EXTRACT_32BITS(&bp[hlen]),
 260                                EXTRACT_32BITS(&bp[hlen + 4])));
 261                 }
 262                 hlen += 8;
 263                 if (ndo->ndo_vflag) {
 264                         ND_TCHECK2(*mh, hlen + 8);
 265                         ND_PRINT((ndo, " %s Keygen Token=%08x:%08x",
 266                                type == IP6M_HOME_TEST ? "Home" : "Care-of",
 267                                EXTRACT_32BITS(&bp[hlen]),
 268                                EXTRACT_32BITS(&bp[hlen + 4])));
 269                 }
 270                 hlen += 8;
 271                 break;
 272         case IP6M_BINDING_UPDATE:
 273                 ND_TCHECK(mh->ip6m_data16[0]);
 274                 ND_PRINT((ndo, " seq#=%u", EXTRACT_16BITS(&mh->ip6m_data16[0])));
 275                 hlen = IP6M_MINLEN;
 276                 ND_TCHECK2(*mh, hlen + 1);
 277                 if (bp[hlen] & 0xf0)
 278                         ND_PRINT((ndo, " "));
 279                 if (bp[hlen] & 0x80)
 280                         ND_PRINT((ndo, "A"));
 281                 if (bp[hlen] & 0x40)
 282                         ND_PRINT((ndo, "H"));
 283                 if (bp[hlen] & 0x20)
 284                         ND_PRINT((ndo, "L"));
 285                 if (bp[hlen] & 0x10)
 286                         ND_PRINT((ndo, "K"));
 287                 /* Reserved (4bits) */
 288                 hlen += 1;
 289                 /* Reserved (8bits) */
 290                 hlen += 1;
 291                 ND_TCHECK2(*mh, hlen + 2);
 292                 /* units of 4 secs */
 293                 ND_PRINT((ndo, " lifetime=%u", EXTRACT_16BITS(&bp[hlen]) << 2));
 294                 hlen += 2;
 295                 break;
 296         case IP6M_BINDING_ACK:
 297                 ND_TCHECK(mh->ip6m_data8[0]);
 298                 ND_PRINT((ndo, " status=%u", mh->ip6m_data8[0]));
 299                 if (mh->ip6m_data8[1] & 0x80)
 300                         ND_PRINT((ndo, " K"));
 301                 /* Reserved (7bits) */
 302                 hlen = IP6M_MINLEN;
 303                 ND_TCHECK2(*mh, hlen + 2);
 304                 ND_PRINT((ndo, " seq#=%u", EXTRACT_16BITS(&bp[hlen])));
 305                 hlen += 2;
 306                 ND_TCHECK2(*mh, hlen + 2);
 307                 /* units of 4 secs */
 308                 ND_PRINT((ndo, " lifetime=%u", EXTRACT_16BITS(&bp[hlen]) << 2));
 309                 hlen += 2;
 310                 break;
 311         case IP6M_BINDING_ERROR:
 312                 ND_TCHECK(mh->ip6m_data8[0]);
 313                 ND_PRINT((ndo, " status=%u", mh->ip6m_data8[0]));
 314                 /* Reserved */
 315                 hlen = IP6M_MINLEN;
 316                 ND_TCHECK2(*mh, hlen + 16);
 317                 ND_PRINT((ndo, " homeaddr %s", ip6addr_string(ndo, &bp[hlen])));
 318                 hlen += 16;
 319                 break;
 320         default:
 321                 ND_PRINT((ndo, " len=%u", mh->ip6m_len));
 322                 return(mhlen);
 323                 break;
 324         }
 325         if (ndo->ndo_vflag)
 326                 mobility_opt_print(ndo, &bp[hlen], mhlen - hlen);
 327
 328         return(mhlen);
 329
 330  trunc:
 331         ND_PRINT((ndo, "[|MOBILITY]"));
 332         return(mhlen);
 333 }