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         version = EXTRACT_U_1(bp);
  68         msg_type = EXTRACT_U_1(bp + 1);
  69         msg_type_str = tok2str(msg_type_values, "unknown (%u)", msg_type);
  70
  71         ND_PRINT("; ItsPduHeader v:%u t:%u-%s", version, msg_type, msg_type_str);
  72 }
  73
  74 static void
  75 print_btp(netdissect_options *ndo,
  76           const u_char *bp)
  77 {
  78         uint16_t dest = EXTRACT_BE_U_2(bp + 0);
  79         uint16_t src = EXTRACT_BE_U_2(bp + 2);
  80         ND_PRINT("; BTP Dst:%u Src:%u", dest, src);
  81 }
  82
  83 static int
  84 print_long_pos_vector(netdissect_options *ndo,
  85                       const u_char *bp)
  86 {
  87         uint32_t lat, lon;
  88
  89         if (!ND_TTEST_LEN(bp, GEONET_ADDR_LEN))
  90                 return (-1);
  91         ND_PRINT("GN_ADDR:%s ", linkaddr_string (ndo, bp, 0, GEONET_ADDR_LEN));
  92
  93         if (!ND_TTEST_8(bp + 12))
  94                 return (-1);
  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 }
 101
 102
 103 /*
 104  * This is the top level routine of the printer.  'p' points
 105  * to the geonet header of the packet.
 106  */
 107 void
 108 geonet_print(netdissect_options *ndo, const u_char *bp, u_int length,
 109              const struct lladdr_info *src)
 110 {
 111         u_int version;
 112         u_int next_hdr;
 113         u_int hdr_type;
 114         u_int hdr_subtype;
 115         uint16_t payload_length;
 116         u_int hop_limit;
 117         const char *next_hdr_txt = "Unknown";
 118         const char *hdr_type_txt = "Unknown";
 119         int hdr_size = -1;
 120
 121         ndo->ndo_protocol = "geonet";
 122         ND_PRINT("GeoNet ");
 123         if (src != NULL)
 124                 ND_PRINT("src:%s", (src->addr_string)(ndo, src->addr));
 125         ND_PRINT("; ");
 126
 127         /* Process Common Header */
 128         if (length < 36)
 129                 goto invalid;
 130
 131         ND_TCHECK_8(bp);
 132         version = EXTRACT_U_1(bp) >> 4;
 133         next_hdr = EXTRACT_U_1(bp) & 0x0f;
 134         hdr_type = EXTRACT_U_1(bp + 1) >> 4;
 135         hdr_subtype = EXTRACT_U_1(bp + 1) & 0x0f;
 136         payload_length = EXTRACT_BE_U_2(bp + 4);
 137         hop_limit = EXTRACT_U_1(bp + 7);
 138
 139         switch (next_hdr) {
 140                 case 0: next_hdr_txt = "Any"; break;
 141                 case 1: next_hdr_txt = "BTP-A"; break;
 142                 case 2: next_hdr_txt = "BTP-B"; break;
 143                 case 3: next_hdr_txt = "IPv6"; break;
 144         }
 145
 146         switch (hdr_type) {
 147                 case 0: hdr_type_txt = "Any"; break;
 148                 case 1: hdr_type_txt = "Beacon"; break;
 149                 case 2: hdr_type_txt = "GeoUnicast"; break;
 150                 case 3: switch (hdr_subtype) {
 151                                 case 0: hdr_type_txt = "GeoAnycastCircle"; break;
 152                                 case 1: hdr_type_txt = "GeoAnycastRect"; break;
 153                                 case 2: hdr_type_txt = "GeoAnycastElipse"; break;
 154                         }
 155                         break;
 156                 case 4: switch (hdr_subtype) {
 157                                 case 0: hdr_type_txt = "GeoBroadcastCircle"; break;
 158                                 case 1: hdr_type_txt = "GeoBroadcastRect"; break;
 159                                 case 2: hdr_type_txt = "GeoBroadcastElipse"; break;
 160                         }
 161                         break;
 162                 case 5: switch (hdr_subtype) {
 163                                 case 0: hdr_type_txt = "TopoScopeBcast-SH"; break;
 164                                 case 1: hdr_type_txt = "TopoScopeBcast-MH"; break;
 165                         }
 166                         break;
 167                 case 6: switch (hdr_subtype) {
 168                                 case 0: hdr_type_txt = "LocService-Request"; break;
 169                                 case 1: hdr_type_txt = "LocService-Reply"; break;
 170                         }
 171                         break;
 172         }
 173
 174         ND_PRINT("v:%u ", version);
 175         ND_PRINT("NH:%u-%s ", next_hdr, next_hdr_txt);
 176         ND_PRINT("HT:%u-%u-%s ", hdr_type, hdr_subtype, hdr_type_txt);
 177         ND_PRINT("HopLim:%u ", hop_limit);
 178         ND_PRINT("Payload:%u ", payload_length);
 179         if (print_long_pos_vector(ndo, bp + 8) == -1)
 180                 goto trunc;
 181
 182         /* Skip Common Header */
 183         length -= 36;
 184         bp += 36;
 185
 186         /* Process Extended Headers */
 187         switch (hdr_type) {
 188                 case 0: /* Any */
 189                         hdr_size = 0;
 190                         break;
 191                 case 1: /* Beacon */
 192                         hdr_size = 0;
 193                         break;
 194                 case 2: /* GeoUnicast */
 195                         break;
 196                 case 3: switch (hdr_subtype) {
 197                                 case 0: /* GeoAnycastCircle */
 198                                         break;
 199                                 case 1: /* GeoAnycastRect */
 200                                         break;
 201                                 case 2: /* GeoAnycastElipse */
 202                                         break;
 203                         }
 204                         break;
 205                 case 4: switch (hdr_subtype) {
 206                                 case 0: /* GeoBroadcastCircle */
 207                                         break;
 208                                 case 1: /* GeoBroadcastRect */
 209                                         break;
 210                                 case 2: /* GeoBroadcastElipse */
 211                                         break;
 212                         }
 213                         break;
 214                 case 5: switch (hdr_subtype) {
 215                                 case 0: /* TopoScopeBcast-SH */
 216                                         hdr_size = 0;
 217                                         break;
 218                                 case 1: /* TopoScopeBcast-MH */
 219                                         hdr_size = 68 - 36;
 220                                         break;
 221                         }
 222                         break;
 223                 case 6: switch (hdr_subtype) {
 224                                 case 0: /* LocService-Request */
 225                                         break;
 226                                 case 1: /* LocService-Reply */
 227                                         break;
 228                         }
 229                         break;
 230         }
 231
 232         /* Skip Extended headers */
 233         if (hdr_size >= 0) {
 234                 if (length < (u_int)hdr_size)
 235                         goto invalid;
 236                 ND_TCHECK_LEN(bp, hdr_size);
 237                 length -= hdr_size;
 238                 bp += hdr_size;
 239                 switch (next_hdr) {
 240                         case 0: /* Any */
 241                                 break;
 242                         case 1:
 243                         case 2: /* BTP A/B */
 244                                 if (length < 4)
 245                                         goto invalid;
 246                                 ND_TCHECK_4(bp);
 247                                 print_btp(ndo, bp);
 248                                 length -= 4;
 249                                 bp += 4;
 250                                 if (length >= 2) {
 251                                         /*
 252                                          * XXX - did print_btp_body()
 253                                          * return if length < 2
 254                                          * because this is optional,
 255                                          * or was that just not
 256                                          * reporting genuine errors?
 257                                          */
 258                                         ND_TCHECK_2(bp);
 259                                         print_btp_body(ndo, bp);
 260                                 }
 261                                 break;
 262                         case 3: /* IPv6 */
 263                                 break;
 264                 }
 265         }
 266
 267         /* Print user data part */
 268         if (ndo->ndo_vflag)
 269                 ND_DEFAULTPRINT(bp, length);
 270         return;
 271
 272 invalid:
 273         ND_PRINT(" Malformed (small) ");
 274         /* XXX - print the remaining data as hex? */
 275         return;
 276
 277 trunc:
 278         nd_print_trunc(ndo);
 279 }