external/bsd/tcpdump/dist/print-dvmrp.c

   1 /*
   2  * Copyright (c) 1995, 1996
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  */
  21
  22 #include <sys/cdefs.h>
  23 #ifndef lint
  24 __RCSID("$NetBSD: print-dvmrp.c,v 1.4 2014/11/20 03:05:03 christos Exp $");
  25 #endif
  26
  27 #define NETDISSECT_REWORKED
  28 #ifdef HAVE_CONFIG_H
  29 #include "config.h"
  30 #endif
  31
  32 #include <tcpdump-stdinc.h>
  33
  34 #include "interface.h"
  35 #include "extract.h"
  36 #include "addrtoname.h"
  37
  38 /*
  39  * DVMRP message types and flag values shamelessly stolen from
  40  * mrouted/dvmrp.h.
  41  */
  42 #define DVMRP_PROBE             1       /* for finding neighbors */
  43 #define DVMRP_REPORT            2       /* for reporting some or all routes */
  44 #define DVMRP_ASK_NEIGHBORS     3       /* sent by mapper, asking for a list */
  45                                         /* of this router's neighbors */
  46 #define DVMRP_NEIGHBORS         4       /* response to such a request */
  47 #define DVMRP_ASK_NEIGHBORS2    5       /* as above, want new format reply */
  48 #define DVMRP_NEIGHBORS2        6
  49 #define DVMRP_PRUNE             7       /* prune message */
  50 #define DVMRP_GRAFT             8       /* graft message */
  51 #define DVMRP_GRAFT_ACK         9       /* graft acknowledgement */
  52
  53 /*
  54  * 'flags' byte values in DVMRP_NEIGHBORS2 reply.
  55  */
  56 #define DVMRP_NF_TUNNEL         0x01    /* neighbors reached via tunnel */
  57 #define DVMRP_NF_SRCRT          0x02    /* tunnel uses IP source routing */
  58 #define DVMRP_NF_DOWN           0x10    /* kernel state of interface */
  59 #define DVMRP_NF_DISABLED       0x20    /* administratively disabled */
  60 #define DVMRP_NF_QUERIER        0x40    /* I am the subnet's querier */
  61
  62 static int print_probe(netdissect_options *, const u_char *, const u_char *, u_int);
  63 static int print_report(netdissect_options *, const u_char *, const u_char *, u_int);
  64 static int print_neighbors(netdissect_options *, const u_char *, const u_char *, u_int);
  65 static int print_neighbors2(netdissect_options *, const u_char *, const u_char *, u_int);
  66 static int print_prune(netdissect_options *, const u_char *);
  67 static int print_graft(netdissect_options *, const u_char *);
  68 static int print_graft_ack(netdissect_options *, const u_char *);
  69
  70 static uint32_t target_level;
  71
  72 void
  73 dvmrp_print(netdissect_options *ndo,
  74             register const u_char *bp, register u_int len)
  75 {
  76         register const u_char *ep;
  77         register u_char type;
  78
  79         ep = (const u_char *)ndo->ndo_snapend;
  80         if (bp >= ep)
  81                 return;
  82
  83         ND_TCHECK(bp[1]);
  84         type = bp[1];
  85
  86         /* Skip IGMP header */
  87         bp += 8;
  88         len -= 8;
  89
  90         switch (type) {
  91
  92         case DVMRP_PROBE:
  93                 ND_PRINT((ndo, " Probe"));
  94                 if (ndo->ndo_vflag) {
  95                         if (print_probe(ndo, bp, ep, len) < 0)
  96                                 goto trunc;
  97                 }
  98                 break;
  99
 100         case DVMRP_REPORT:
 101                 ND_PRINT((ndo, " Report"));
 102                 if (ndo->ndo_vflag > 1) {
 103                         if (print_report(ndo, bp, ep, len) < 0)
 104                                 goto trunc;
 105                 }
 106                 break;
 107
 108         case DVMRP_ASK_NEIGHBORS:
 109                 ND_PRINT((ndo, " Ask-neighbors(old)"));
 110                 break;
 111
 112         case DVMRP_NEIGHBORS:
 113                 ND_PRINT((ndo, " Neighbors(old)"));
 114                 if (print_neighbors(ndo, bp, ep, len) < 0)
 115                         goto trunc;
 116                 break;
 117
 118         case DVMRP_ASK_NEIGHBORS2:
 119                 ND_PRINT((ndo, " Ask-neighbors2"));
 120                 break;
 121
 122         case DVMRP_NEIGHBORS2:
 123                 ND_PRINT((ndo, " Neighbors2"));
 124                 /*
 125                  * extract version and capabilities from IGMP group
 126                  * address field
 127                  */
 128                 bp -= 4;
 129                 ND_TCHECK2(bp[0], 4);
 130                 target_level = (bp[0] << 24) | (bp[1] << 16) |
 131                     (bp[2] << 8) | bp[3];
 132                 bp += 4;
 133                 if (print_neighbors2(ndo, bp, ep, len) < 0)
 134                         goto trunc;
 135                 break;
 136
 137         case DVMRP_PRUNE:
 138                 ND_PRINT((ndo, " Prune"));
 139                 if (print_prune(ndo, bp) < 0)
 140                         goto trunc;
 141                 break;
 142
 143         case DVMRP_GRAFT:
 144                 ND_PRINT((ndo, " Graft"));
 145                 if (print_graft(ndo, bp) < 0)
 146                         goto trunc;
 147                 break;
 148
 149         case DVMRP_GRAFT_ACK:
 150                 ND_PRINT((ndo, " Graft-ACK"));
 151                 if (print_graft_ack(ndo, bp) < 0)
 152                         goto trunc;
 153                 break;
 154
 155         default:
 156                 ND_PRINT((ndo, " [type %d]", type));
 157                 break;
 158         }
 159         return;
 160
 161 trunc:
 162         ND_PRINT((ndo, "[|dvmrp]"));
 163         return;
 164 }
 165
 166 static int
 167 print_report(netdissect_options *ndo,
 168              register const u_char *bp, register const u_char *ep,
 169              register u_int len)
 170 {
 171         register uint32_t mask, origin;
 172         register int metric, done;
 173         register u_int i, width;
 174
 175         while (len > 0) {
 176                 if (len < 3) {
 177                         ND_PRINT((ndo, " [|]"));
 178                         return (0);
 179                 }
 180                 ND_TCHECK2(bp[0], 3);
 181                 mask = (uint32_t)0xff << 24 | bp[0] << 16 | bp[1] << 8 | bp[2];
 182                 width = 1;
 183                 if (bp[0])
 184                         width = 2;
 185                 if (bp[1])
 186                         width = 3;
 187                 if (bp[2])
 188                         width = 4;
 189
 190                 ND_PRINT((ndo, "\n\tMask %s", intoa(htonl(mask))));
 191                 bp += 3;
 192                 len -= 3;
 193                 do {
 194                         if (bp + width + 1 > ep) {
 195                                 ND_PRINT((ndo, " [|]"));
 196                                 return (0);
 197                         }
 198                         if (len < width + 1) {
 199                                 ND_PRINT((ndo, "\n\t  [Truncated Report]"));
 200                                 return (0);
 201                         }
 202                         origin = 0;
 203                         for (i = 0; i < width; ++i) {
 204                                 ND_TCHECK(*bp);
 205                                 origin = origin << 8 | *bp++;
 206                         }
 207                         for ( ; i < 4; ++i)
 208                                 origin <<= 8;
 209
 210                         ND_TCHECK(*bp);
 211                         metric = *bp++;
 212                         done = metric & 0x80;
 213                         metric &= 0x7f;
 214                         ND_PRINT((ndo, "\n\t  %s metric %d", intoa(htonl(origin)),
 215                                 metric));
 216                         len -= width + 1;
 217                 } while (!done);
 218         }
 219         return (0);
 220 trunc:
 221         return (-1);
 222 }
 223
 224 static int
 225 print_probe(netdissect_options *ndo,
 226             register const u_char *bp, register const u_char *ep,
 227             register u_int len)
 228 {
 229         register uint32_t genid;
 230
 231         ND_TCHECK2(bp[0], 4);
 232         if ((len < 4) || ((bp + 4) > ep)) {
 233                 /* { (ctags) */
 234                 ND_PRINT((ndo, " [|}"));
 235                 return (0);
 236         }
 237         genid = (bp[0] << 24) | (bp[1] << 16) | (bp[2] << 8) | bp[3];
 238         bp += 4;
 239         len -= 4;
 240         ND_PRINT((ndo, ndo->ndo_vflag > 1 ? "\n\t" : " "));
 241         ND_PRINT((ndo, "genid %u", genid));
 242         if (ndo->ndo_vflag < 2)
 243                 return (0);
 244
 245         while ((len > 0) && (bp < ep)) {
 246                 ND_TCHECK2(bp[0], 4);
 247                 ND_PRINT((ndo, "\n\tneighbor %s", ipaddr_string(ndo, bp)));
 248                 bp += 4; len -= 4;
 249         }
 250         return (0);
 251 trunc:
 252         return (-1);
 253 }
 254
 255 static int
 256 print_neighbors(netdissect_options *ndo,
 257                 register const u_char *bp, register const u_char *ep,
 258                 register u_int len)
 259 {
 260         const u_char *laddr;
 261         register u_char metric;
 262         register u_char thresh;
 263         register int ncount;
 264
 265         while (len > 0 && bp < ep) {
 266                 ND_TCHECK2(bp[0], 7);
 267                 laddr = bp;
 268                 bp += 4;
 269                 metric = *bp++;
 270                 thresh = *bp++;
 271                 ncount = *bp++;
 272                 len -= 7;
 273                 while (--ncount >= 0) {
 274                         ND_TCHECK2(bp[0], 4);
 275                         ND_PRINT((ndo, " [%s ->", ipaddr_string(ndo, laddr)));
 276                         ND_PRINT((ndo, " %s, (%d/%d)]",
 277                                    ipaddr_string(ndo, bp), metric, thresh));
 278                         bp += 4;
 279                         len -= 4;
 280                 }
 281         }
 282         return (0);
 283 trunc:
 284         return (-1);
 285 }
 286
 287 static int
 288 print_neighbors2(netdissect_options *ndo,
 289                  register const u_char *bp, register const u_char *ep,
 290                  register u_int len)
 291 {
 292         const u_char *laddr;
 293         register u_char metric, thresh, flags;
 294         register int ncount;
 295
 296         ND_PRINT((ndo, " (v %d.%d):",
 297                (int)target_level & 0xff,
 298                (int)(target_level >> 8) & 0xff));
 299
 300         while (len > 0 && bp < ep) {
 301                 ND_TCHECK2(bp[0], 8);
 302                 laddr = bp;
 303                 bp += 4;
 304                 metric = *bp++;
 305                 thresh = *bp++;
 306                 flags = *bp++;
 307                 ncount = *bp++;
 308                 len -= 8;
 309                 while (--ncount >= 0 && (len >= 4) && (bp + 4) <= ep) {
 310                         ND_PRINT((ndo, " [%s -> ", ipaddr_string(ndo, laddr)));
 311                         ND_PRINT((ndo, "%s (%d/%d", ipaddr_string(ndo, bp),
 312                                      metric, thresh));
 313                         if (flags & DVMRP_NF_TUNNEL)
 314                                 ND_PRINT((ndo, "/tunnel"));
 315                         if (flags & DVMRP_NF_SRCRT)
 316                                 ND_PRINT((ndo, "/srcrt"));
 317                         if (flags & DVMRP_NF_QUERIER)
 318                                 ND_PRINT((ndo, "/querier"));
 319                         if (flags & DVMRP_NF_DISABLED)
 320                                 ND_PRINT((ndo, "/disabled"));
 321                         if (flags & DVMRP_NF_DOWN)
 322                                 ND_PRINT((ndo, "/down"));
 323                         ND_PRINT((ndo, ")]"));
 324                         bp += 4;
 325                         len -= 4;
 326                 }
 327                 if (ncount != -1) {
 328                         ND_PRINT((ndo, " [|]"));
 329                         return (0);
 330                 }
 331         }
 332         return (0);
 333 trunc:
 334         return (-1);
 335 }
 336
 337 static int
 338 print_prune(netdissect_options *ndo,
 339             register const u_char *bp)
 340 {
 341         ND_TCHECK2(bp[0], 12);
 342         ND_PRINT((ndo, " src %s grp %s", ipaddr_string(ndo, bp), ipaddr_string(ndo, bp + 4)));
 343         bp += 8;
 344         ND_PRINT((ndo, " timer "));
 345         relts_print(ndo, EXTRACT_32BITS(bp));
 346         return (0);
 347 trunc:
 348         return (-1);
 349 }
 350
 351 static int
 352 print_graft(netdissect_options *ndo,
 353             register const u_char *bp)
 354 {
 355         ND_TCHECK2(bp[0], 8);
 356         ND_PRINT((ndo, " src %s grp %s", ipaddr_string(ndo, bp), ipaddr_string(ndo, bp + 4)));
 357         return (0);
 358 trunc:
 359         return (-1);
 360 }
 361
 362 static int
 363 print_graft_ack(netdissect_options *ndo,
 364                 register const u_char *bp)
 365 {
 366         ND_TCHECK2(bp[0], 8);
 367         ND_PRINT((ndo, " src %s grp %s", ipaddr_string(ndo, bp), ipaddr_string(ndo, bp + 4)));
 368         return (0);
 369 trunc:
 370         return (-1);
 371 }