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

   1 /*
   2  * Copyright (c) 2013 The TCPDUMP project
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that: (1) source code
   6  * distributions retain the above copyright notice and this paragraph
   7  * in its entirety, and (2) distributions including binary code include
   8  * the above copyright notice and this paragraph in its entirety in
   9  * the documentation or other materials provided with the distribution.
  10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
  11  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
  12  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  13  * FOR A PARTICULAR PURPOSE.
  14  *
  15  * Original code by Ola Martin Lykkja (ola.lykkja@q-free.com)
  16  */
  17
  18 /* \summary: ISO CALM FAST and ETSI GeoNetworking printer */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include <config.h>
  22 #endif
  23
  24 #include "netdissect-stdinc.h"
  25
  26 #include "netdissect.h"
  27 #include "extract.h"
  28 #include "addrtoname.h"
  29
  30
  31 /*
  32    ETSI TS 102 636-5-1 V1.1.1 (2011-02)
  33    Intelligent Transport Systems (ITS); Vehicular Communications; GeoNetworking;
  34    Part 5: Transport Protocols; Sub-part 1: Basic Transport Protocol
  35
  36    ETSI TS 102 636-4-1 V1.1.1 (2011-06)
  37    Intelligent Transport Systems (ITS); Vehicular communications; GeoNetworking;
  38    Part 4: Geographical addressing and forwarding for point-to-point and point-to-multipoint communications;
  39    Sub-part 1: Media-Independent Functionality
  40 */
  41
  42 #define GEONET_ADDR_LEN 8
  43
  44 static const struct tok msg_type_values[] = {
  45         {   0, "CAM" },
  46         {   1, "DENM" },
  47         { 101, "TPEGM" },
  48         { 102, "TSPDM" },
  49         { 103, "VPM" },
  50         { 104, "SRM" },
  51         { 105, "SLAM" },
  52         { 106, "ecoCAM" },
  53         { 107, "ITM" },
  54         { 150, "SA" },
  55         {   0, NULL }
  56 };
  57
  58 static void
  59 print_btp_body(netdissect_options *ndo,
  60                const u_char *bp)
  61 {
  62         u_int version;
  63         u_int msg_type;
  64         const char *msg_type_str;
  65
  66         /* Assuming ItsDpuHeader */
  67         /* 2 bytes ND_TCHECKed in geonet_print() */
  68         version = EXTRACT_U_1(bp);
  69         msg_type = EXTRACT_U_1(bp + 1);
  70         msg_type_str = tok2str(msg_type_values, "unknown (%u)", msg_type);
  71
  72         ND_PRINT("; ItsPduHeader v:%u t:%u-%s", version, msg_type, msg_type_str);
  73 }
  74
  75 static void
  76 print_btp(netdissect_options *ndo,
  77           const u_char *bp)
  78 {
  79         /* 4 bytes ND_TCHECKed in geonet_print() */
  80         uint16_t dest = EXTRACT_BE_U_2(bp + 0);
  81         uint16_t src = EXTRACT_BE_U_2(bp + 2);
  82         ND_PRINT("; BTP Dst:%u Src:%u", dest, src);
  83 }
  84
  85 static int
  86 print_long_pos_vector(netdissect_options *ndo,
  87                       const u_char *bp)
  88 {
  89         uint32_t lat, lon;
  90
  91         ND_TCHECK_LEN(bp, GEONET_ADDR_LEN);
  92         ND_PRINT("GN_ADDR:%s ", linkaddr_string (ndo, bp, 0, GEONET_ADDR_LEN));
  93
  94         ND_TCHECK_8(bp + 12);
  95         lat = EXTRACT_BE_U_4(bp + 12);
  96         ND_PRINT("lat:%u ", lat);
  97         lon = EXTRACT_BE_U_4(bp + 16);
  98         ND_PRINT("lon:%u", lon);
  99         return (0);
 100 trunc:
 101         return -1;
 102 }
 103
 104
 105 /*
 106  * This is the top level routine of the printer.  'p' points
 107  * to the geonet header of the packet.
 108  */
 109 void
 110 geonet_print(netdissect_options *ndo, const u_char *bp, u_int length,
 111              const struct lladdr_info *src)
 112 {
 113         u_int version;
 114         u_int next_hdr;
 115         u_int hdr_type;
 116         u_int hdr_subtype;
 117         uint16_t payload_length;
 118         u_int hop_limit;
 119         const char *next_hdr_txt = "Unknown";
 120         const char *hdr_type_txt = "Unknown";
 121         int hdr_size = -1;
 122
 123         ndo->ndo_protocol = "geonet";
 124         ND_PRINT("GeoNet ");
 125         if (src != NULL)
 126                 ND_PRINT("src:%s", (src->addr_string)(ndo, src->addr));
 127         ND_PRINT("; ");
 128
 129         /* Process Common Header */
 130         if (length < 36)
 131                 goto invalid;
 132
 133         ND_TCHECK_8(bp);
 134         version = EXTRACT_U_1(bp) >> 4;
 135         next_hdr = EXTRACT_U_1(bp) & 0x0f;
 136         hdr_type = EXTRACT_U_1(bp + 1) >> 4;
 137         hdr_subtype = EXTRACT_U_1(bp + 1) & 0x0f;
 138         payload_length = EXTRACT_BE_U_2(bp + 4);
 139         hop_limit = EXTRACT_U_1(bp + 7);
 140
 141         switch (next_hdr) {
 142                 case 0: next_hdr_txt = "Any"; break;
 143                 case 1: next_hdr_txt = "BTP-A"; break;
 144                 case 2: next_hdr_txt = "BTP-B"; break;
 145                 case 3: next_hdr_txt = "IPv6"; break;
 146         }
 147
 148         switch (hdr_type) {
 149                 case 0: hdr_type_txt = "Any"; break;
 150                 case 1: hdr_type_txt = "Beacon"; break;
 151                 case 2: hdr_type_txt = "GeoUnicast"; break;
 152                 case 3: switch (hdr_subtype) {
 153                                 case 0: hdr_type_txt = "GeoAnycastCircle"; break;
 154                                 case 1: hdr_type_txt = "GeoAnycastRect"; break;
 155                                 case 2: hdr_type_txt = "GeoAnycastElipse"; break;
 156                         }
 157                         break;
 158                 case 4: switch (hdr_subtype) {
 159                                 case 0: hdr_type_txt = "GeoBroadcastCircle"; break;
 160                                 case 1: hdr_type_txt = "GeoBroadcastRect"; break;
 161                                 case 2: hdr_type_txt = "GeoBroadcastElipse"; break;
 162                         }
 163                         break;
 164                 case 5: switch (hdr_subtype) {
 165                                 case 0: hdr_type_txt = "TopoScopeBcast-SH"; break;
 166                                 case 1: hdr_type_txt = "TopoScopeBcast-MH"; break;
 167                         }
 168                         break;
 169                 case 6: switch (hdr_subtype) {
 170                                 case 0: hdr_type_txt = "LocService-Request"; break;
 171                                 case 1: hdr_type_txt = "LocService-Reply"; break;
 172                         }
 173                         break;
 174         }
 175
 176         ND_PRINT("v:%u ", version);
 177         ND_PRINT("NH:%u-%s ", next_hdr, next_hdr_txt);
 178         ND_PRINT("HT:%u-%u-%s ", hdr_type, hdr_subtype, hdr_type_txt);
 179         ND_PRINT("HopLim:%u ", hop_limit);
 180         ND_PRINT("Payload:%u ", payload_length);
 181         if (print_long_pos_vector(ndo, bp + 8) == -1)
 182                 goto trunc;
 183
 184         /* Skip Common Header */
 185         length -= 36;
 186         bp += 36;
 187
 188         /* Process Extended Headers */
 189         switch (hdr_type) {
 190                 case 0: /* Any */
 191                         hdr_size = 0;
 192                         break;
 193                 case 1: /* Beacon */
 194                         hdr_size = 0;
 195                         break;
 196                 case 2: /* GeoUnicast */
 197                         break;
 198                 case 3: switch (hdr_subtype) {
 199                                 case 0: /* GeoAnycastCircle */
 200                                         break;
 201                                 case 1: /* GeoAnycastRect */
 202                                         break;
 203                                 case 2: /* GeoAnycastElipse */
 204                                         break;
 205                         }
 206                         break;
 207                 case 4: switch (hdr_subtype) {
 208                                 case 0: /* GeoBroadcastCircle */
 209                                         break;
 210                                 case 1: /* GeoBroadcastRect */
 211                                         break;
 212                                 case 2: /* GeoBroadcastElipse */
 213                                         break;
 214                         }
 215                         break;
 216                 case 5: switch (hdr_subtype) {
 217                                 case 0: /* TopoScopeBcast-SH */
 218                                         hdr_size = 0;
 219                                         break;
 220                                 case 1: /* TopoScopeBcast-MH */
 221                                         hdr_size = 68 - 36;
 222                                         break;
 223                         }
 224                         break;
 225                 case 6: switch (hdr_subtype) {
 226                                 case 0: /* LocService-Request */
 227                                         break;
 228                                 case 1: /* LocService-Reply */
 229                                         break;
 230                         }
 231                         break;
 232         }
 233
 234         /* Skip Extended headers */
 235         if (hdr_size >= 0) {
 236                 if (length < (u_int)hdr_size)
 237                         goto invalid;
 238                 ND_TCHECK_LEN(bp, hdr_size);
 239                 length -= hdr_size;
 240                 bp += hdr_size;
 241                 switch (next_hdr) {
 242                         case 0: /* Any */
 243                                 break;
 244                         case 1:
 245                         case 2: /* BTP A/B */
 246                                 if (length < 4)
 247                                         goto invalid;
 248                                 ND_TCHECK_4(bp);
 249                                 print_btp(ndo, bp);
 250                                 length -= 4;
 251                                 bp += 4;
 252                                 if (length >= 2) {
 253                                         /*
 254                                          * XXX - did print_btp_body()
 255                                          * return if length < 2
 256                                          * because this is optional,
 257                                          * or was that just not
 258                                          * reporting genuine errors?
 259                                          */
 260                                         ND_TCHECK_2(bp);
 261                                         print_btp_body(ndo, bp);
 262                                 }
 263                                 break;
 264                         case 3: /* IPv6 */
 265                                 break;
 266                 }
 267         }
 268
 269         /* Print user data part */
 270         if (ndo->ndo_vflag)
 271                 ND_DEFAULTPRINT(bp, length);
 272         return;
 273
 274 invalid:
 275         ND_PRINT(" Malformed (small) ");
 276         /* XXX - print the remaining data as hex? */
 277         return;
 278
 279 trunc:
 280         nd_print_trunc(ndo);
 281 }