contrib/tcpdump/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
  85 static const char *
  86 format_id(const u_char *id)
  87 {
  88     static char buf[25];
  89     snprintf(buf, 25, "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x",
  90              id[0], id[1], id[2], id[3], id[4], id[5], id[6], id[7]);
  91     buf[24] = '\0';
  92     return buf;
  93 }
  94
  95 static const unsigned char v4prefix[16] =
  96     {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };
  97
  98 static const char *
  99 format_prefix(const u_char *prefix, unsigned char plen)
 100 {
 101     static char buf[50];
 102     if(plen >= 96 && memcmp(prefix, v4prefix, 12) == 0)
 103         snprintf(buf, 50, "%s/%u", ipaddr_string(prefix + 12), plen - 96);
 104     else
 105         snprintf(buf, 50, "%s/%u", ip6addr_string(prefix), plen);
 106     buf[49] = '\0';
 107     return buf;
 108 }
 109
 110 static const char *
 111 format_address(const u_char *prefix)
 112 {
 113     if(memcmp(prefix, v4prefix, 12) == 0)
 114         return ipaddr_string(prefix + 12);
 115     else
 116         return ip6addr_string(prefix);
 117 }
 118
 119 static int
 120 network_prefix(int ae, int plen, unsigned int omitted,
 121                const unsigned char *p, const unsigned char *dp,
 122                unsigned int len, unsigned char *p_r)
 123 {
 124     unsigned pb;
 125     unsigned char prefix[16];
 126
 127     if(plen >= 0)
 128         pb = (plen + 7) / 8;
 129     else if(ae == 1)
 130         pb = 4;
 131     else
 132         pb = 16;
 133
 134     if(pb > 16)
 135         return -1;
 136
 137     memset(prefix, 0, 16);
 138
 139     switch(ae) {
 140     case 0: break;
 141     case 1:
 142         if(omitted > 4 || pb > 4 || (pb > omitted && len < pb - omitted))
 143             return -1;
 144         memcpy(prefix, v4prefix, 12);
 145         if(omitted) {
 146             if (dp == NULL) return -1;
 147             memcpy(prefix, dp, 12 + omitted);
 148         }
 149         if(pb > omitted) memcpy(prefix + 12 + omitted, p, pb - omitted);
 150         break;
 151     case 2:
 152         if(omitted > 16 || (pb > omitted && len < pb - omitted))
 153             return -1;
 154         if(omitted) {
 155             if (dp == NULL) return -1;
 156             memcpy(prefix, dp, omitted);
 157         }
 158         if(pb > omitted) memcpy(prefix + omitted, p, pb - omitted);
 159         break;
 160     case 3:
 161         if(pb > 8 && len < pb - 8) return -1;
 162         prefix[0] = 0xfe;
 163         prefix[1] = 0x80;
 164         if(pb > 8) memcpy(prefix + 8, p, pb - 8);
 165         break;
 166     default:
 167         return -1;
 168     }
 169
 170     memcpy(p_r, prefix, 16);
 171     return 1;
 172 }
 173
 174 static int
 175 network_address(int ae, const unsigned char *a, unsigned int len,
 176                 unsigned char *a_r)
 177 {
 178     return network_prefix(ae, -1, 0, a, NULL, len, a_r);
 179 }
 180
 181 #define ICHECK(i, l) \
 182         if ((i) + (l) > bodylen || (i) + (l) > length) goto corrupt;
 183
 184 static void
 185 babel_print_v2(const u_char *cp, u_int length) {
 186     u_int i;
 187     u_short bodylen;
 188     u_char v4_prefix[16] =
 189         {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };
 190     u_char v6_prefix[16] = {0};
 191
 192     TCHECK2(*cp, 4);
 193     if (length < 4)
 194         goto corrupt;
 195     bodylen = EXTRACT_16BITS(cp + 2);
 196     printf(" (%u)", bodylen);
 197
 198     /* Process the TLVs in the body */
 199     i = 0;
 200     while(i < bodylen) {
 201         const u_char *message;
 202         u_char type, len;
 203
 204         message = cp + 4 + i;
 205         TCHECK2(*message, 2);
 206         ICHECK(i, 2);
 207         type = message[0];
 208         len = message[1];
 209
 210         TCHECK2(*message, 2 + len);
 211         ICHECK(i, 2 + len);
 212
 213         switch(type) {
 214         case MESSAGE_PAD1: {
 215             if(!vflag)
 216                 printf(" pad1");
 217             else
 218                 printf("\n\tPad 1");
 219         }
 220             break;
 221
 222         case MESSAGE_PADN: {
 223             if(!vflag)
 224                 printf(" padN");
 225             else
 226                 printf("\n\tPad %d", len + 2);
 227         }
 228             break;
 229
 230         case MESSAGE_ACK_REQ: {
 231             u_short nonce, interval;
 232             if(!vflag)
 233                 printf(" ack-req");
 234             else {
 235                 printf("\n\tAcknowledgment Request ");
 236                 if(len < 6) goto corrupt;
 237                 nonce = EXTRACT_16BITS(message + 4);
 238                 interval = EXTRACT_16BITS(message + 6);
 239                 printf("%04x %d", nonce, interval);
 240             }
 241         }
 242             break;
 243
 244         case MESSAGE_ACK: {
 245             u_short nonce;
 246             if(!vflag)
 247                 printf(" ack");
 248             else {
 249                 printf("\n\tAcknowledgment ");
 250                 if(len < 2) goto corrupt;
 251                 nonce = EXTRACT_16BITS(message + 2);
 252                 printf("%04x", nonce);
 253             }
 254         }
 255             break;
 256
 257         case MESSAGE_HELLO:  {
 258             u_short seqno, interval;
 259             if(!vflag)
 260                 printf(" hello");
 261             else {
 262                 printf("\n\tHello ");
 263                 if(len < 6) goto corrupt;
 264                 seqno = EXTRACT_16BITS(message + 4);
 265                 interval = EXTRACT_16BITS(message + 6);
 266                 printf("seqno %u interval %u", seqno, interval);
 267             }
 268         }
 269             break;
 270
 271         case MESSAGE_IHU: {
 272             unsigned short txcost, interval;
 273             if(!vflag)
 274                 printf(" ihu");
 275             else {
 276                 u_char address[16];
 277                 int rc;
 278                 printf("\n\tIHU ");
 279                 if(len < 6) goto corrupt;
 280                 txcost = EXTRACT_16BITS(message + 4);
 281                 interval = EXTRACT_16BITS(message + 6);
 282                 rc = network_address(message[2], message + 8, len - 6, address);
 283                 if(rc < 0) { printf("[|babel]"); break; }
 284                 printf("%s txcost %u interval %d",
 285                        format_address(address), txcost, interval);
 286             }
 287         }
 288             break;
 289
 290         case MESSAGE_ROUTER_ID: {
 291             if(!vflag)
 292                 printf(" router-id");
 293             else {
 294                 printf("\n\tRouter Id");
 295                 if(len < 10) goto corrupt;
 296                 printf(" %s", format_id(message + 4));
 297             }
 298         }
 299             break;
 300
 301         case MESSAGE_NH: {
 302             if(!vflag)
 303                 printf(" nh");
 304             else {
 305                 int rc;
 306                 u_char nh[16];
 307                 printf("\n\tNext Hop");
 308                 if(len < 2) goto corrupt;
 309                 rc = network_address(message[2], message + 4, len - 2, nh);
 310                 if(rc < 0) goto corrupt;
 311                 printf(" %s", format_address(nh));
 312             }
 313         }
 314             break;
 315
 316         case MESSAGE_UPDATE: {
 317             if(!vflag) {
 318                 printf(" update");
 319                 if(len < 1)
 320                     printf("/truncated");
 321                 else
 322                     printf("%s%s%s",
 323                            (message[3] & 0x80) ? "/prefix": "",
 324                            (message[3] & 0x40) ? "/id" : "",
 325                            (message[3] & 0x3f) ? "/unknown" : "");
 326             } else {
 327                 u_short interval, seqno, metric;
 328                 u_char plen;
 329                 int rc;
 330                 u_char prefix[16];
 331                 printf("\n\tUpdate");
 332                 if(len < 10) goto corrupt;
 333                 plen = message[4] + (message[2] == 1 ? 96 : 0);
 334                 rc = network_prefix(message[2], message[4], message[5],
 335                                     message + 12,
 336                                     message[2] == 1 ? v4_prefix : v6_prefix,
 337                                     len - 10, prefix);
 338                 if(rc < 0) goto corrupt;
 339                 interval = EXTRACT_16BITS(message + 6);
 340                 seqno = EXTRACT_16BITS(message + 8);
 341                 metric = EXTRACT_16BITS(message + 10);
 342                 printf("%s%s%s %s metric %u seqno %u interval %u",
 343                        (message[3] & 0x80) ? "/prefix": "",
 344                        (message[3] & 0x40) ? "/id" : "",
 345                        (message[3] & 0x3f) ? "/unknown" : "",
 346                        format_prefix(prefix, plen),
 347                        metric, seqno, interval);
 348                 if(message[3] & 0x80) {
 349                     if(message[2] == 1)
 350                         memcpy(v4_prefix, prefix, 16);
 351                     else
 352                         memcpy(v6_prefix, prefix, 16);
 353                 }
 354             }
 355         }
 356             break;
 357
 358         case MESSAGE_REQUEST: {
 359             if(!vflag)
 360                 printf(" request");
 361             else {
 362                 int rc;
 363                 u_char prefix[16], plen;
 364                 printf("\n\tRequest ");
 365                 if(len < 2) goto corrupt;
 366                 plen = message[3] + (message[2] == 1 ? 96 : 0);
 367                 rc = network_prefix(message[2], message[3], 0,
 368                                     message + 4, NULL, len - 2, prefix);
 369                 if(rc < 0) goto corrupt;
 370                 plen = message[3] + (message[2] == 1 ? 96 : 0);
 371                 printf("for %s",
 372                        message[2] == 0 ? "any" : format_prefix(prefix, plen));
 373             }
 374         }
 375             break;
 376
 377         case MESSAGE_MH_REQUEST : {
 378             if(!vflag)
 379                 printf(" mh-request");
 380             else {
 381                 int rc;
 382                 u_short seqno;
 383                 u_char prefix[16], plen;
 384                 printf("\n\tMH-Request ");
 385                 if(len < 14) goto corrupt;
 386                 seqno = EXTRACT_16BITS(message + 4);
 387                 rc = network_prefix(message[2], message[3], 0,
 388                                     message + 16, NULL, len - 14, prefix);
 389                 if(rc < 0) goto corrupt;
 390                 plen = message[3] + (message[2] == 1 ? 96 : 0);
 391                 printf("(%u hops) for %s seqno %u id %s",
 392                        message[6], format_prefix(prefix, plen),
 393                        seqno, format_id(message + 8));
 394             }
 395         }
 396             break;
 397         default:
 398             if(!vflag)
 399                 printf(" unknown");
 400             else
 401                 printf("\n\tUnknown message type %d", type);
 402         }
 403         i += len + 2;
 404     }
 405     return;
 406
 407  trunc:
 408     printf(" [|babel]");
 409     return;
 410
 411  corrupt:
 412     printf(" (corrupt)");
 413     return;
 414 }