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 #ifdef INET6
 108         snprintf(buf, 50, "%s/%u", ip6addr_string(prefix), plen);
 109 #else
 110         snprintf(buf, 50, "IPv6 addresses not supported");
 111 #endif
 112     buf[49] = '\0';
 113     return buf;
 114 }
 115
 116 static const char *
 117 format_address(const u_char *prefix)
 118 {
 119     if(memcmp(prefix, v4prefix, 12) == 0)
 120         return ipaddr_string(prefix + 12);
 121     else
 122 #ifdef INET6
 123         return ip6addr_string(prefix);
 124 #else
 125         return "IPv6 addresses not supported";
 126 #endif
 127 }
 128
 129 static int
 130 network_prefix(int ae, int plen, unsigned int omitted,
 131                const unsigned char *p, const unsigned char *dp,
 132                unsigned int len, unsigned char *p_r)
 133 {
 134     unsigned pb;
 135     unsigned char prefix[16];
 136
 137     if(plen >= 0)
 138         pb = (plen + 7) / 8;
 139     else if(ae == 1)
 140         pb = 4;
 141     else
 142         pb = 16;
 143
 144     if(pb > 16)
 145         return -1;
 146
 147     memset(prefix, 0, 16);
 148
 149     switch(ae) {
 150     case 0: break;
 151     case 1:
 152         if(omitted > 4 || pb > 4 || (pb > omitted && len < pb - omitted))
 153             return -1;
 154         memcpy(prefix, v4prefix, 12);
 155         if(omitted) {
 156             if (dp == NULL) return -1;
 157             memcpy(prefix, dp, 12 + omitted);
 158         }
 159         if(pb > omitted) memcpy(prefix + 12 + omitted, p, pb - omitted);
 160         break;
 161     case 2:
 162         if(omitted > 16 || (pb > omitted && len < pb - omitted))
 163             return -1;
 164         if(omitted) {
 165             if (dp == NULL) return -1;
 166             memcpy(prefix, dp, omitted);
 167         }
 168         if(pb > omitted) memcpy(prefix + omitted, p, pb - omitted);
 169         break;
 170     case 3:
 171         if(pb > 8 && len < pb - 8) return -1;
 172         prefix[0] = 0xfe;
 173         prefix[1] = 0x80;
 174         if(pb > 8) memcpy(prefix + 8, p, pb - 8);
 175         break;
 176     default:
 177         return -1;
 178     }
 179
 180     memcpy(p_r, prefix, 16);
 181     return 1;
 182 }
 183
 184 static int
 185 network_address(int ae, const unsigned char *a, unsigned int len,
 186                 unsigned char *a_r)
 187 {
 188     return network_prefix(ae, -1, 0, a, NULL, len, a_r);
 189 }
 190
 191 #define ICHECK(i, l) \
 192         if ((i) + (l) > bodylen || (i) + (l) > length) goto corrupt;
 193
 194 static void
 195 babel_print_v2(const u_char *cp, u_int length) {
 196     u_int i;
 197     u_short bodylen;
 198     u_char v4_prefix[16] =
 199         {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };
 200     u_char v6_prefix[16] = {0};
 201
 202     TCHECK2(*cp, 4);
 203     if (length < 4)
 204         goto corrupt;
 205     bodylen = EXTRACT_16BITS(cp + 2);
 206     printf(" (%u)", bodylen);
 207
 208     /* Process the TLVs in the body */
 209     i = 0;
 210     while(i < bodylen) {
 211         const u_char *message;
 212         u_int type, len;
 213
 214         message = cp + 4 + i;
 215
 216         TCHECK2(*message, 1);
 217         if((type = message[0]) == MESSAGE_PAD1) {
 218             printf(vflag ? "\n\tPad 1" : " pad1");
 219             i += 1;
 220             continue;
 221         }
 222
 223         TCHECK2(*message, 2);
 224         ICHECK(i, 2);
 225         len = message[1];
 226
 227         TCHECK2(*message, 2 + len);
 228         ICHECK(i, 2 + len);
 229
 230         switch(type) {
 231         case MESSAGE_PADN: {
 232             if(!vflag)
 233                 printf(" padN");
 234             else
 235                 printf("\n\tPad %d", len + 2);
 236         }
 237             break;
 238
 239         case MESSAGE_ACK_REQ: {
 240             u_short nonce, interval;
 241             if(!vflag)
 242                 printf(" ack-req");
 243             else {
 244                 printf("\n\tAcknowledgment Request ");
 245                 if(len < 6) goto corrupt;
 246                 nonce = EXTRACT_16BITS(message + 4);
 247                 interval = EXTRACT_16BITS(message + 6);
 248                 printf("%04x %d", nonce, interval);
 249             }
 250         }
 251             break;
 252
 253         case MESSAGE_ACK: {
 254             u_short nonce;
 255             if(!vflag)
 256                 printf(" ack");
 257             else {
 258                 printf("\n\tAcknowledgment ");
 259                 if(len < 2) goto corrupt;
 260                 nonce = EXTRACT_16BITS(message + 2);
 261                 printf("%04x", nonce);
 262             }
 263         }
 264             break;
 265
 266         case MESSAGE_HELLO:  {
 267             u_short seqno, interval;
 268             if(!vflag)
 269                 printf(" hello");
 270             else {
 271                 printf("\n\tHello ");
 272                 if(len < 6) goto corrupt;
 273                 seqno = EXTRACT_16BITS(message + 4);
 274                 interval = EXTRACT_16BITS(message + 6);
 275                 printf("seqno %u interval %u", seqno, interval);
 276             }
 277         }
 278             break;
 279
 280         case MESSAGE_IHU: {
 281             unsigned short txcost, interval;
 282             if(!vflag)
 283                 printf(" ihu");
 284             else {
 285                 u_char address[16];
 286                 int rc;
 287                 printf("\n\tIHU ");
 288                 if(len < 6) goto corrupt;
 289                 txcost = EXTRACT_16BITS(message + 4);
 290                 interval = EXTRACT_16BITS(message + 6);
 291                 rc = network_address(message[2], message + 8, len - 6, address);
 292                 if(rc < 0) { printf("[|babel]"); break; }
 293                 printf("%s txcost %u interval %d",
 294                        format_address(address), txcost, interval);
 295             }
 296         }
 297             break;
 298
 299         case MESSAGE_ROUTER_ID: {
 300             if(!vflag)
 301                 printf(" router-id");
 302             else {
 303                 printf("\n\tRouter Id");
 304                 if(len < 10) goto corrupt;
 305                 printf(" %s", format_id(message + 4));
 306             }
 307         }
 308             break;
 309
 310         case MESSAGE_NH: {
 311             if(!vflag)
 312                 printf(" nh");
 313             else {
 314                 int rc;
 315                 u_char nh[16];
 316                 printf("\n\tNext Hop");
 317                 if(len < 2) goto corrupt;
 318                 rc = network_address(message[2], message + 4, len - 2, nh);
 319                 if(rc < 0) goto corrupt;
 320                 printf(" %s", format_address(nh));
 321             }
 322         }
 323             break;
 324
 325         case MESSAGE_UPDATE: {
 326             if(!vflag) {
 327                 printf(" update");
 328                 if(len < 1)
 329                     printf("/truncated");
 330                 else
 331                     printf("%s%s%s",
 332                            (message[3] & 0x80) ? "/prefix": "",
 333                            (message[3] & 0x40) ? "/id" : "",
 334                            (message[3] & 0x3f) ? "/unknown" : "");
 335             } else {
 336                 u_short interval, seqno, metric;
 337                 u_char plen;
 338                 int rc;
 339                 u_char prefix[16];
 340                 printf("\n\tUpdate");
 341                 if(len < 10) goto corrupt;
 342                 plen = message[4] + (message[2] == 1 ? 96 : 0);
 343                 rc = network_prefix(message[2], message[4], message[5],
 344                                     message + 12,
 345                                     message[2] == 1 ? v4_prefix : v6_prefix,
 346                                     len - 10, prefix);
 347                 if(rc < 0) goto corrupt;
 348                 interval = EXTRACT_16BITS(message + 6);
 349                 seqno = EXTRACT_16BITS(message + 8);
 350                 metric = EXTRACT_16BITS(message + 10);
 351                 printf("%s%s%s %s metric %u seqno %u interval %u",
 352                        (message[3] & 0x80) ? "/prefix": "",
 353                        (message[3] & 0x40) ? "/id" : "",
 354                        (message[3] & 0x3f) ? "/unknown" : "",
 355                        format_prefix(prefix, plen),
 356                        metric, seqno, interval);
 357                 if(message[3] & 0x80) {
 358                     if(message[2] == 1)
 359                         memcpy(v4_prefix, prefix, 16);
 360                     else
 361                         memcpy(v6_prefix, prefix, 16);
 362                 }
 363             }
 364         }
 365             break;
 366
 367         case MESSAGE_REQUEST: {
 368             if(!vflag)
 369                 printf(" request");
 370             else {
 371                 int rc;
 372                 u_char prefix[16], plen;
 373                 printf("\n\tRequest ");
 374                 if(len < 2) goto corrupt;
 375                 plen = message[3] + (message[2] == 1 ? 96 : 0);
 376                 rc = network_prefix(message[2], message[3], 0,
 377                                     message + 4, NULL, len - 2, prefix);
 378                 if(rc < 0) goto corrupt;
 379                 plen = message[3] + (message[2] == 1 ? 96 : 0);
 380                 printf("for %s",
 381                        message[2] == 0 ? "any" : format_prefix(prefix, plen));
 382             }
 383         }
 384             break;
 385
 386         case MESSAGE_MH_REQUEST : {
 387             if(!vflag)
 388                 printf(" mh-request");
 389             else {
 390                 int rc;
 391                 u_short seqno;
 392                 u_char prefix[16], plen;
 393                 printf("\n\tMH-Request ");
 394                 if(len < 14) goto corrupt;
 395                 seqno = EXTRACT_16BITS(message + 4);
 396                 rc = network_prefix(message[2], message[3], 0,
 397                                     message + 16, NULL, len - 14, prefix);
 398                 if(rc < 0) goto corrupt;
 399                 plen = message[3] + (message[2] == 1 ? 96 : 0);
 400                 printf("(%u hops) for %s seqno %u id %s",
 401                        message[6], format_prefix(prefix, plen),
 402                        seqno, format_id(message + 8));
 403             }
 404         }
 405             break;
 406         case MESSAGE_TSPC :
 407             if(!vflag)
 408                 printf(" tspc");
 409             else {
 410                 printf("\n\tTS/PC ");
 411                 if(len < 6) goto corrupt;
 412                 printf("timestamp %u packetcounter %u", EXTRACT_32BITS (message + 4),
 413                        EXTRACT_16BITS(message + 2));
 414             }
 415             break;
 416         case MESSAGE_HMAC : {
 417             if(!vflag)
 418                 printf(" hmac");
 419             else {
 420                 unsigned j;
 421                 printf("\n\tHMAC ");
 422                 if(len < 18) goto corrupt;
 423                 printf("key-id %u digest-%u ", EXTRACT_16BITS(message + 2), len - 2);
 424                 for (j = 0; j < len - 2; j++)
 425                     printf ("%02X", message[4 + j]);
 426             }
 427         }
 428             break;
 429         default:
 430             if(!vflag)
 431                 printf(" unknown");
 432             else
 433                 printf("\n\tUnknown message type %d", type);
 434         }
 435         i += len + 2;
 436     }
 437     return;
 438
 439  trunc:
 440     printf(" [|babel]");
 441     return;
 442
 443  corrupt:
 444     printf(" (corrupt)");
 445     return;
 446 }