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

   1 /*
   2  * Copyright (c) 2007-2011 Grégoire Henry, Juliusz Chroboczek
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  * 3. Neither the name of the project nor the names of its contributors
  13  *    may be used to endorse or promote products derived from this software
  14  *    without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #ifdef HAVE_CONFIG_H
  30 #include "config.h"
  31 #endif
  32
  33 #include <tcpdump-stdinc.h>
  34
  35 #include <stdio.h>
  36 #include <string.h>
  37
  38 #include "addrtoname.h"
  39 #include "interface.h"
  40 #include "extract.h"
  41
  42 static void babel_print_v2(const u_char *cp, u_int length);
  43
  44 void
  45 babel_print(const u_char *cp, u_int length) {
  46     printf("babel");
  47
  48     TCHECK2(*cp, 4);
  49
  50     if(cp[0] != 42) {
  51         printf(" malformed header");
  52         return;
  53     } else {
  54         printf(" %d", cp[1]);
  55     }
  56
  57     switch(cp[1]) {
  58     case 2:
  59         babel_print_v2(cp,length);
  60         break;
  61     default:
  62         printf(" unknown version");
  63         break;
  64     }
  65
  66     return;
  67
  68  trunc:
  69     printf(" [|babel]");
  70     return;
  71 }
  72
  73 #define MESSAGE_PAD1 0
  74 #define MESSAGE_PADN 1
  75 #define MESSAGE_ACK_REQ 2
  76 #define MESSAGE_ACK 3
  77 #define MESSAGE_HELLO 4
  78 #define MESSAGE_IHU 5
  79 #define MESSAGE_ROUTER_ID 6
  80 #define MESSAGE_NH 7
  81 #define MESSAGE_UPDATE 8
  82 #define MESSAGE_REQUEST 9
  83 #define MESSAGE_MH_REQUEST 10
  84 #define MESSAGE_TSPC 11
  85 #define MESSAGE_HMAC 12
  86
  87 static const char *
  88 format_id(const u_char *id)
  89 {
  90     static char buf[25];
  91     snprintf(buf, 25, "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x",
  92              id[0], id[1], id[2], id[3], id[4], id[5], id[6], id[7]);
  93     buf[24] = '\0';
  94     return buf;
  95 }
  96
  97 static const unsigned char v4prefix[16] =
  98     {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };
  99
 100 static const char *
 101 format_prefix(const u_char *prefix, unsigned char plen)
 102 {
 103     static char buf[50];
 104     if(plen >= 96 && memcmp(prefix, v4prefix, 12) == 0)
 105         snprintf(buf, 50, "%s/%u", ipaddr_string(prefix + 12), plen - 96);
 106     else
 107         snprintf(buf, 50, "%s/%u", ip6addr_string(prefix), plen);
 108     buf[49] = '\0';
 109     return buf;
 110 }
 111
 112 static const char *
 113 format_address(const u_char *prefix)
 114 {
 115     if(memcmp(prefix, v4prefix, 12) == 0)
 116         return ipaddr_string(prefix + 12);
 117     else
 118         return ip6addr_string(prefix);
 119 }
 120
 121 static int
 122 network_prefix(int ae, int plen, unsigned int omitted,
 123                const unsigned char *p, const unsigned char *dp,
 124                unsigned int len, unsigned char *p_r)
 125 {
 126     unsigned pb;
 127     unsigned char prefix[16];
 128
 129     if(plen >= 0)
 130         pb = (plen + 7) / 8;
 131     else if(ae == 1)
 132         pb = 4;
 133     else
 134         pb = 16;
 135
 136     if(pb > 16)
 137         return -1;
 138
 139     memset(prefix, 0, 16);
 140
 141     switch(ae) {
 142     case 0: break;
 143     case 1:
 144         if(omitted > 4 || pb > 4 || (pb > omitted && len < pb - omitted))
 145             return -1;
 146         memcpy(prefix, v4prefix, 12);
 147         if(omitted) {
 148             if (dp == NULL) return -1;
 149             memcpy(prefix, dp, 12 + omitted);
 150         }
 151         if(pb > omitted) memcpy(prefix + 12 + omitted, p, pb - omitted);
 152         break;
 153     case 2:
 154         if(omitted > 16 || (pb > omitted && len < pb - omitted))
 155             return -1;
 156         if(omitted) {
 157             if (dp == NULL) return -1;
 158             memcpy(prefix, dp, omitted);
 159         }
 160         if(pb > omitted) memcpy(prefix + omitted, p, pb - omitted);
 161         break;
 162     case 3:
 163         if(pb > 8 && len < pb - 8) return -1;
 164         prefix[0] = 0xfe;
 165         prefix[1] = 0x80;
 166         if(pb > 8) memcpy(prefix + 8, p, pb - 8);
 167         break;
 168     default:
 169         return -1;
 170     }
 171
 172     memcpy(p_r, prefix, 16);
 173     return 1;
 174 }
 175
 176 static int
 177 network_address(int ae, const unsigned char *a, unsigned int len,
 178                 unsigned char *a_r)
 179 {
 180     return network_prefix(ae, -1, 0, a, NULL, len, a_r);
 181 }
 182
 183 #define ICHECK(i, l) \
 184         if ((i) + (l) > bodylen || (i) + (l) > length) goto corrupt;
 185
 186 static void
 187 babel_print_v2(const u_char *cp, u_int length) {
 188     u_int i;
 189     u_short bodylen;
 190     u_char v4_prefix[16] =
 191         {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };
 192     u_char v6_prefix[16] = {0};
 193
 194     TCHECK2(*cp, 4);
 195     if (length < 4)
 196         goto corrupt;
 197     bodylen = EXTRACT_16BITS(cp + 2);
 198     printf(" (%u)", bodylen);
 199
 200     /* Process the TLVs in the body */
 201     i = 0;
 202     while(i < bodylen) {
 203         const u_char *message;
 204         u_int type, len;
 205
 206         message = cp + 4 + i;
 207         TCHECK2(*message, 2);
 208         ICHECK(i, 2);
 209         type = message[0];
 210         len = message[1];
 211
 212         TCHECK2(*message, 2 + len);
 213         ICHECK(i, 2 + len);
 214
 215         switch(type) {
 216         case MESSAGE_PAD1: {
 217             if(!vflag)
 218                 printf(" pad1");
 219             else
 220                 printf("\n\tPad 1");
 221         }
 222             break;
 223
 224         case MESSAGE_PADN: {
 225             if(!vflag)
 226                 printf(" padN");
 227             else
 228                 printf("\n\tPad %d", len + 2);
 229         }
 230             break;
 231
 232         case MESSAGE_ACK_REQ: {
 233             u_short nonce, interval;
 234             if(!vflag)
 235                 printf(" ack-req");
 236             else {
 237                 printf("\n\tAcknowledgment Request ");
 238                 if(len < 6) goto corrupt;
 239                 nonce = EXTRACT_16BITS(message + 4);
 240                 interval = EXTRACT_16BITS(message + 6);
 241                 printf("%04x %d", nonce, interval);
 242             }
 243         }
 244             break;
 245
 246         case MESSAGE_ACK: {
 247             u_short nonce;
 248             if(!vflag)
 249                 printf(" ack");
 250             else {
 251                 printf("\n\tAcknowledgment ");
 252                 if(len < 2) goto corrupt;
 253                 nonce = EXTRACT_16BITS(message + 2);
 254                 printf("%04x", nonce);
 255             }
 256         }
 257             break;
 258
 259         case MESSAGE_HELLO:  {
 260             u_short seqno, interval;
 261             if(!vflag)
 262                 printf(" hello");
 263             else {
 264                 printf("\n\tHello ");
 265                 if(len < 6) goto corrupt;
 266                 seqno = EXTRACT_16BITS(message + 4);
 267                 interval = EXTRACT_16BITS(message + 6);
 268                 printf("seqno %u interval %u", seqno, interval);
 269             }
 270         }
 271             break;
 272
 273         case MESSAGE_IHU: {
 274             unsigned short txcost, interval;
 275             if(!vflag)
 276                 printf(" ihu");
 277             else {
 278                 u_char address[16];
 279                 int rc;
 280                 printf("\n\tIHU ");
 281                 if(len < 6) goto corrupt;
 282                 txcost = EXTRACT_16BITS(message + 4);
 283                 interval = EXTRACT_16BITS(message + 6);
 284                 rc = network_address(message[2], message + 8, len - 6, address);
 285                 if(rc < 0) { printf("[|babel]"); break; }
 286                 printf("%s txcost %u interval %d",
 287                        format_address(address), txcost, interval);
 288             }
 289         }
 290             break;
 291
 292         case MESSAGE_ROUTER_ID: {
 293             if(!vflag)
 294                 printf(" router-id");
 295             else {
 296                 printf("\n\tRouter Id");
 297                 if(len < 10) goto corrupt;
 298                 printf(" %s", format_id(message + 4));
 299             }
 300         }
 301             break;
 302
 303         case MESSAGE_NH: {
 304             if(!vflag)
 305                 printf(" nh");
 306             else {
 307                 int rc;
 308                 u_char nh[16];
 309                 printf("\n\tNext Hop");
 310                 if(len < 2) goto corrupt;
 311                 rc = network_address(message[2], message + 4, len - 2, nh);
 312                 if(rc < 0) goto corrupt;
 313                 printf(" %s", format_address(nh));
 314             }
 315         }
 316             break;
 317
 318         case MESSAGE_UPDATE: {
 319             if(!vflag) {
 320                 printf(" update");
 321                 if(len < 1)
 322                     printf("/truncated");
 323                 else
 324                     printf("%s%s%s",
 325                            (message[3] & 0x80) ? "/prefix": "",
 326                            (message[3] & 0x40) ? "/id" : "",
 327                            (message[3] & 0x3f) ? "/unknown" : "");
 328             } else {
 329                 u_short interval, seqno, metric;
 330                 u_char plen;
 331                 int rc;
 332                 u_char prefix[16];
 333                 printf("\n\tUpdate");
 334                 if(len < 10) goto corrupt;
 335                 plen = message[4] + (message[2] == 1 ? 96 : 0);
 336                 rc = network_prefix(message[2], message[4], message[5],
 337                                     message + 12,
 338                                     message[2] == 1 ? v4_prefix : v6_prefix,
 339                                     len - 10, prefix);
 340                 if(rc < 0) goto corrupt;
 341                 interval = EXTRACT_16BITS(message + 6);
 342                 seqno = EXTRACT_16BITS(message + 8);
 343                 metric = EXTRACT_16BITS(message + 10);
 344                 printf("%s%s%s %s metric %u seqno %u interval %u",
 345                        (message[3] & 0x80) ? "/prefix": "",
 346                        (message[3] & 0x40) ? "/id" : "",
 347                        (message[3] & 0x3f) ? "/unknown" : "",
 348                        format_prefix(prefix, plen),
 349                        metric, seqno, interval);
 350                 if(message[3] & 0x80) {
 351                     if(message[2] == 1)
 352                         memcpy(v4_prefix, prefix, 16);
 353                     else
 354                         memcpy(v6_prefix, prefix, 16);
 355                 }
 356             }
 357         }
 358             break;
 359
 360         case MESSAGE_REQUEST: {
 361             if(!vflag)
 362                 printf(" request");
 363             else {
 364                 int rc;
 365                 u_char prefix[16], plen;
 366                 printf("\n\tRequest ");
 367                 if(len < 2) goto corrupt;
 368                 plen = message[3] + (message[2] == 1 ? 96 : 0);
 369                 rc = network_prefix(message[2], message[3], 0,
 370                                     message + 4, NULL, len - 2, prefix);
 371                 if(rc < 0) goto corrupt;
 372                 plen = message[3] + (message[2] == 1 ? 96 : 0);
 373                 printf("for %s",
 374                        message[2] == 0 ? "any" : format_prefix(prefix, plen));
 375             }
 376         }
 377             break;
 378
 379         case MESSAGE_MH_REQUEST : {
 380             if(!vflag)
 381                 printf(" mh-request");
 382             else {
 383                 int rc;
 384                 u_short seqno;
 385                 u_char prefix[16], plen;
 386                 printf("\n\tMH-Request ");
 387                 if(len < 14) goto corrupt;
 388                 seqno = EXTRACT_16BITS(message + 4);
 389                 rc = network_prefix(message[2], message[3], 0,
 390                                     message + 16, NULL, len - 14, prefix);
 391                 if(rc < 0) goto corrupt;
 392                 plen = message[3] + (message[2] == 1 ? 96 : 0);
 393                 printf("(%u hops) for %s seqno %u id %s",
 394                        message[6], format_prefix(prefix, plen),
 395                        seqno, format_id(message + 8));
 396             }
 397         }
 398             break;
 399         case MESSAGE_TSPC :
 400             if(!vflag)
 401                 printf(" tspc");
 402             else {
 403                 printf("\n\tTS/PC ");
 404                 if(len < 6) goto corrupt;
 405                 printf("timestamp %u packetcounter %u", EXTRACT_32BITS (message + 4),
 406                        EXTRACT_16BITS(message + 2));
 407             }
 408             break;
 409         case MESSAGE_HMAC : {
 410             if(!vflag)
 411                 printf(" hmac");
 412             else {
 413                 unsigned j;
 414                 printf("\n\tHMAC ");
 415                 if(len < 18) goto corrupt;
 416                 printf("key-id %u digest-%u ", EXTRACT_16BITS(message + 2), len - 2);
 417                 for (j = 0; j < len - 2; j++)
 418                     printf ("%02X", message[4 + j]);
 419             }
 420         }
 421             break;
 422         default:
 423             if(!vflag)
 424                 printf(" unknown");
 425             else
 426                 printf("\n\tUnknown message type %d", type);
 427         }
 428         i += len + 2;
 429     }
 430     return;
 431
 432  trunc:
 433     printf(" [|babel]");
 434     return;
 435
 436  corrupt:
 437     printf(" (corrupt)");
 438     return;
 439 }