epan/dissectors/packet-gvcp.c

   1 /* packet-gvcp.c
   2  * Routines for gvcp (GigEVision Control Protocol) dissection
   3  * Copyright 2010, Adrian Daerr <adrian.daerr@gmx.de>
   4  *
   5  * $Id$
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version 2
  14  * of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
  24  * USA.
  25  */
  26 /*
  27  * Credits to Falco Hirschenberger for his description of GVCP
  28  * ( http://gitorious.org/opengigevision )
  29  *
  30  * GVCP is part of the GigE-Vision interface (a closed standard) to
  31  * so-called industrial cameras.
  32  *
  33  * see also: http://en.wikipedia.org/wiki/GigE_vision
  34  *
  35  * This dissector is based on traffic analysis alone, as the
  36  * description of the GVCP is accessible only to members of the
  37  * Automated Imaging Association. The resulting packet description is
  38  * therefore likely to be incomplete or inaccurate.
  39  *
  40  * TODO:
  41  * - fill holes (missing opcodes / field meanings / ...)
  42  * - conversation level:
  43  *   . validity of anwers (is CMD packet properly ACK'ed by follow-up packet?)
  44  *   . reassemble, unzip, store and parse XML file, so that addresses
  45  *     may be translated back into register names
  46  *
  47  */
  48 #include "config.h"
  49
  50 #include <epan/packet.h>
  51 #include <epan/wmem/wmem.h>
  52
  53 #define GVCP_PORT 3956
  54
  55 static int proto_gvcp = -1;
  56 static int hf_gvcp_type = -1;
  57 static int hf_gvcp_opcode = -1;
  58 static int hf_gvcp_payloadsize = -1;
  59 static int hf_gvcp_sequenceno = -1;
  60 static int hf_gvcp_address = -1;
  61 static int hf_gvcp_value = -1;
  62 static int hf_gvcp_address2 = -1;
  63 static int hf_gvcp_value2 = -1;
  64 static int hf_gvcp_remainder = -1;
  65 static int hf_gvcp_nwritten = -1;
  66 static int hf_gvcp_nbytes = -1;
  67 static int hf_gvcp_unknown16 = -1;
  68 static int hf_gvcp_data = -1;
  69 static int hf_gvcp_ip = -1;
  70 static int hf_gvcp_ether = -1;
  71 static int hf_gvcp_netmask = -1;
  72 static gint ett_gvcp = -1;
  73
  74 static const value_string opcode_names[] = {
  75   { 0x02, "Discovery ping" },
  76   { 0x03, "Discovery pong" },
  77   { 0x04, "Assign IP" },
  78   { 0x05, "Ack IP change" },
  79   { 0x40, "Resend request" },
  80   { 0x80, "Register read request" },
  81   { 0x81, "Register read answer" },
  82   { 0x82, "Register write request" },
  83   { 0x83, "Register write answer" },
  84   { 0x84, "MemBlock read request" },
  85   { 0x85, "MemBlock read answer" },
  86   { 0x86, "MemBlock write request" },
  87   { 0x87, "MemBlock write answer" },
  88   { 0, NULL }
  89 };
  90
  91 #if 0
  92 static const value_string opcode_short_names[] = {
  93   { 0x02, "Disc_Ping" },
  94   { 0x03, "Disc_Pong" },
  95   { 0x04, "Assign IP" },
  96   { 0x05, "Ack IP" },
  97   { 0x40, "Res_Req" },
  98   { 0x80, "Reg_Rd_Req" },
  99   { 0x81, "Reg_Rd_Ans" },
 100   { 0x82, "Reg_Wr_Req" },
 101   { 0x83, "Reg_Wr_Ans" },
 102   { 0x84, "Blk_Rd_Req" },
 103   { 0x85, "Blk_Rd_Ans" },
 104   { 0x86, "Blk_Wr_Req" },
 105   { 0x87, "Blk_Wr_Ans" },
 106   { 0, NULL }
 107 };
 108 #endif
 109
 110 static int
 111 dissect_gvcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
 112 {
 113   guint16 packet_type, packet_opcode, packet_plsize;
 114   wmem_strbuf_t *info;
 115
 116   /* Check that there's enough data */
 117   if (tvb_length(tvb) < 8)
 118     return 0;
 119
 120   /* Do some tests on what seems to be PDU field to determine if we
 121      really have a GVCP packet here, otherwise return 0 to give
 122      another dissector a chance to dissect it. */
 123   packet_type = tvb_get_ntohs(tvb, 0);
 124
 125   /* packets from the PC to the camera on GVCP_PORT seem to always
 126      start with 0x4201 or 0x4200 */
 127   if ( pinfo->destport == GVCP_PORT &&
 128        (packet_type != 0x4200 && packet_type != 0x4201) )
 129     return 0;
 130
 131   /* packets from the camera GVCP_PORT to the PC seem to start
 132      with 0x0000, but can be different on error condition (e.g. 0x8005) */
 133 #if 0
 134   if ( pinfo->srcport == GVCP_PORT && tvb_get_ntohs(tvb, 0) != 0x0 )
 135     return 0;
 136 #endif
 137
 138   col_set_str(pinfo->cinfo, COL_PROTOCOL, "GVCP");
 139   /* Clear out stuff in the info column */
 140   col_clear(pinfo->cinfo,COL_INFO);
 141
 142   /* dissect 8 byte header */
 143   packet_opcode = tvb_get_ntohs(tvb, 2);
 144   packet_plsize = tvb_get_ntohs(tvb, 4);
 145
 146   /* allocate growable info string */
 147   info = wmem_strbuf_new(wmem_packet_scope(), val_to_str(packet_opcode, opcode_names, "Unknown opcode (0x%04x)"));
 148
 149   /* check that GVCP header+payload match total packet size */
 150   if (tvb_reported_length(tvb) < 8+(guint32)packet_plsize) {
 151     wmem_strbuf_append_printf(info, " (truncated? %u bytes missing)",
 152                               (8 + packet_plsize) - tvb_reported_length(tvb));
 153     col_add_str(pinfo->cinfo, COL_INFO, wmem_strbuf_get_str(info));
 154     return tvb_length(tvb);/* or should we assume this is not GVCP, return 0?*/
 155   }
 156   if (tvb_reported_length(tvb) > 8+(guint32)packet_plsize) {
 157     wmem_strbuf_append_printf(info, " (%u excess bytes)",
 158                               tvb_reported_length(tvb) - (8 + packet_plsize));
 159     col_add_str(pinfo->cinfo, COL_INFO, wmem_strbuf_get_str(info));
 160     return tvb_length(tvb);/* or should we assume this is not GVCP, return 0?*/
 161   }
 162   if (packet_plsize & 3) {/* payload is always a multiple of 4 bytes */
 163     wmem_strbuf_append(info, " (payload is not multiple of 4 bytes)");
 164     col_add_str(pinfo->cinfo, COL_INFO, wmem_strbuf_get_str(info));
 165     return tvb_length(tvb);/* or should we assume this is not GVCP, return 0?*/
 166   }
 167
 168   /* switch just concerned with building a meaningfull Info column string */
 169
 170   switch (packet_opcode) {
 171   case 0x04: /* Assign new temporary IP */
 172     if (packet_plsize < 24) {/* 56 bytes seem to be normal */
 173       wmem_strbuf_append(info, " <missing args>");
 174     } else { /* packet contain new network configuration */
 175       wmem_strbuf_append_printf(info, "%d.%d.%d.%d to %s",
 176                                 tvb_get_guint8(tvb, 28), tvb_get_guint8(tvb, 29),
 177                                 tvb_get_guint8(tvb, 30), tvb_get_guint8(tvb, 31),
 178                                 tvb_bytes_to_str_punct(tvb, 10, 6, ':'));
 179     }
 180     break;
 181   case 0x80: /* Register Read Request */
 182   case 0x81: /* Register Read Answer */
 183     if (packet_plsize == 0) {
 184       wmem_strbuf_append(info, " <missing arg(s)>");
 185     } else { /* packet contains address(es) to read from */
 186       wmem_strbuf_append_printf(info, " 0x%08x", tvb_get_ntohl(tvb, 8));
 187       if (packet_plsize >= 8) {
 188         wmem_strbuf_append_printf(info, ", 0x%08x", tvb_get_ntohl(tvb, 12));
 189         if (packet_plsize >= 12)
 190           wmem_strbuf_append(info, ", ...");
 191       }
 192     }
 193     break;
 194   case 0x82: /* Register Write Request */
 195     if (packet_plsize < 8) {
 196       wmem_strbuf_append(info, " <missing arg(s)>");
 197     } else { /* packet contains address/value pairs to read from */
 198       wmem_strbuf_append_printf(info, " *0x%08x = 0x%08x", tvb_get_ntohl(tvb, 8),
 199                                 tvb_get_ntohl(tvb, 12));
 200       if (packet_plsize >= 16) {
 201         wmem_strbuf_append_printf(info, ", *0x%08x = 0x%08x",
 202                                   tvb_get_ntohl(tvb, 16), tvb_get_ntohl(tvb, 20));
 203         if (packet_plsize >= 24)
 204           wmem_strbuf_append(info, ", ...");
 205       }
 206     }
 207     break;
 208   case 0x83: /* Register Write Answer */
 209     if (packet_plsize < 4) {
 210       wmem_strbuf_append(info, " <missing arg>");
 211     } else {
 212       wmem_strbuf_append_printf(info, " %d register%s written",
 213                                 tvb_get_ntohl(tvb, 8),
 214                                 tvb_get_ntohl(tvb, 8)==1?"":"s");
 215     }
 216     break;
 217   case 0x84: /* Block Read Request */
 218     if (packet_plsize < 8) {
 219       wmem_strbuf_append(info, " <missing args>");
 220     } else { /* packet contains address/size pair to read from */
 221       wmem_strbuf_append_printf(info, " 0x%08x (%d bytes, X=0x%04x)",
 222                                 tvb_get_ntohl(tvb, 8), tvb_get_ntohs(tvb, 14),
 223                                 tvb_get_ntohs(tvb, 12));
 224       if (packet_plsize > 8) {
 225         wmem_strbuf_append(info, "; excess payload");
 226       }
 227     }
 228     break;
 229   case 0x85: /* Block Read Answer */
 230     if (packet_plsize < 8) {
 231       wmem_strbuf_append(info, " <missing args>");
 232     } else { /* packet contains desired data */
 233       wmem_strbuf_append_printf(info, " %d bytes from 0x%08x", packet_plsize - 4,
 234                                 tvb_get_ntohl(tvb, 8));
 235     }
 236     break;
 237   case 0x86: /* Block Write Request */
 238     if (packet_plsize < 8) {
 239       wmem_strbuf_append(info, " <missing args>");
 240     } else { /* packet contains desired data */
 241       wmem_strbuf_append_printf(info, " *0x%08x = <%d bytes>",
 242                                 tvb_get_ntohl(tvb, 8), packet_plsize - 4);
 243     }
 244     break;
 245   case 0x87: /* Block Write Answer */
 246     if (packet_plsize < 4) {
 247       wmem_strbuf_append(info, " <missing arg>");
 248     } else {
 249       wmem_strbuf_append_printf(info, " %d bytes written", tvb_get_ntohl(tvb, 8));
 250     }
 251     break;
 252   }
 253
 254   col_add_str(pinfo->cinfo, COL_INFO, wmem_strbuf_get_str(info));
 255
 256   if (tree) { /* we are being asked for details */
 257     proto_item *ti = NULL;
 258     proto_tree *gvcp_tree = NULL;
 259
 260     ti = proto_tree_add_item(tree, proto_gvcp, tvb, 0, -1, ENC_NA);
 261     gvcp_tree = proto_item_add_subtree(ti, ett_gvcp);
 262     proto_tree_add_item(gvcp_tree, hf_gvcp_type, tvb, 0, 2, ENC_BIG_ENDIAN);
 263     proto_tree_add_item(gvcp_tree, hf_gvcp_opcode, tvb, 2, 2, ENC_BIG_ENDIAN);
 264     proto_tree_add_item(gvcp_tree, hf_gvcp_payloadsize, tvb, 4, 2, ENC_BIG_ENDIAN);
 265     proto_tree_add_item(gvcp_tree, hf_gvcp_sequenceno, tvb, 6, 2, ENC_BIG_ENDIAN);
 266
 267     /* opcode specific fields */
 268     switch (packet_opcode) {
 269     case 0x04: /* Assign new temporary network configuration */
 270       if (packet_plsize >= 48) {
 271         proto_tree_add_item(gvcp_tree, hf_gvcp_ether, tvb, 10, 6, ENC_NA);
 272         proto_tree_add_item(gvcp_tree, hf_gvcp_ip, tvb, 28, 4, ENC_BIG_ENDIAN);
 273         proto_tree_add_item(gvcp_tree, hf_gvcp_netmask, tvb, 44, 4, ENC_BIG_ENDIAN);
 274       }
 275       break;
 276     case 0x80: /* Register Read Request */
 277       if (packet_plsize >= 4) {
 278         proto_tree_add_item(gvcp_tree, hf_gvcp_address, tvb, 8, 4, ENC_BIG_ENDIAN);
 279         if (packet_plsize >= 8) {
 280           proto_tree_add_item(gvcp_tree, hf_gvcp_address2, tvb, 12, 4, ENC_BIG_ENDIAN);
 281           if (packet_plsize >= 12)
 282             proto_tree_add_item(gvcp_tree, hf_gvcp_remainder, tvb, 16, -1, ENC_NA);
 283         }
 284       }
 285       break;
 286     case 0x81: /* Register Read Answer */
 287       if (packet_plsize >= 4) {
 288         proto_tree_add_item(gvcp_tree, hf_gvcp_value, tvb, 8, 4, ENC_BIG_ENDIAN);
 289         if (packet_plsize >= 8) {
 290           proto_tree_add_item(gvcp_tree, hf_gvcp_value2, tvb, 12, 4, ENC_BIG_ENDIAN);
 291           if (packet_plsize >= 12)
 292             proto_tree_add_item(gvcp_tree, hf_gvcp_remainder, tvb, 16, -1, ENC_NA);
 293         }
 294       }
 295       break;
 296     case 0x82: /* Register Write Request */
 297       if (packet_plsize >= 8) {
 298         proto_tree_add_item(gvcp_tree, hf_gvcp_address, tvb, 8, 4, ENC_BIG_ENDIAN);
 299         proto_tree_add_item(gvcp_tree, hf_gvcp_value, tvb, 12, 4, ENC_BIG_ENDIAN);
 300         if (packet_plsize >= 16) {
 301           proto_tree_add_item(gvcp_tree, hf_gvcp_address2, tvb, 16, 4, ENC_BIG_ENDIAN);
 302           proto_tree_add_item(gvcp_tree, hf_gvcp_value2, tvb, 20, 4, ENC_BIG_ENDIAN);
 303           if (packet_plsize >= 24)
 304             proto_tree_add_item(gvcp_tree, hf_gvcp_remainder, tvb, 24, -1, ENC_NA);
 305         }
 306       }
 307       break;
 308     case 0x83: /* Register Write Answer */
 309       if (packet_plsize >= 4)
 310         proto_tree_add_item(gvcp_tree, hf_gvcp_nwritten, tvb, 8, 4, ENC_BIG_ENDIAN);
 311       break;
 312     case 0x84: /* Block Read Request */
 313       if (packet_plsize >= 8) {
 314         proto_tree_add_item(gvcp_tree, hf_gvcp_address, tvb, 8, 4, ENC_BIG_ENDIAN);
 315         proto_tree_add_item(gvcp_tree, hf_gvcp_unknown16, tvb, 12, 2, ENC_BIG_ENDIAN);
 316         proto_tree_add_item(gvcp_tree, hf_gvcp_nbytes, tvb, 14, 2, ENC_BIG_ENDIAN);
 317       }
 318       break;
 319     case 0x85: /* Block Read Answer */
 320     case 0x86: /* Block Write Request */
 321       if (packet_plsize >= 8) {
 322         proto_tree_add_item(gvcp_tree, hf_gvcp_address, tvb, 8, 4, ENC_BIG_ENDIAN);
 323         proto_tree_add_item(gvcp_tree, hf_gvcp_data, tvb, 12, -1, ENC_NA);
 324       }
 325       break;
 326     case 0x87: /* Block Write Answer */
 327       if (packet_plsize >= 4)
 328         proto_tree_add_item(gvcp_tree, hf_gvcp_nbytes, tvb, 10, 2, ENC_BIG_ENDIAN);
 329       break;
 330     default:
 331       if (packet_plsize > 0)
 332         proto_tree_add_item(gvcp_tree, hf_gvcp_data, tvb, 8, -1, ENC_NA);
 333       break;
 334     }
 335
 336   }
 337
 338   return tvb_length(tvb);
 339 }
 340
 341 void
 342 proto_register_gvcp(void)
 343 {
 344   static hf_register_info hf[] = {
 345     { &hf_gvcp_type,
 346       { "GVCP Type", "gvcp.type",
 347         FT_UINT16, BASE_HEX,
 348         NULL, 0x0,
 349         NULL, HFILL }
 350     },
 351     { &hf_gvcp_opcode,
 352       { "GVCP Opcode", "gvcp.opcode",
 353         FT_UINT16, BASE_HEX,
 354         VALS(opcode_names), 0x0,
 355         NULL, HFILL }
 356     },
 357     { &hf_gvcp_payloadsize,
 358       { "GVCP Payload bytes", "gvcp.size",
 359         FT_UINT16, BASE_DEC,
 360         NULL, 0x0,
 361         NULL, HFILL }
 362     },
 363     { &hf_gvcp_sequenceno,
 364       { "GVCP Sequence number", "gvcp.seqn",
 365         FT_UINT16, BASE_DEC,
 366         NULL, 0x0,
 367         NULL, HFILL }
 368     },
 369     { &hf_gvcp_address,
 370       { "Address", "gvcp.address",
 371         FT_UINT32, BASE_HEX,
 372         NULL, 0x0,
 373         NULL, HFILL }
 374     },
 375     { &hf_gvcp_value,
 376       { "Value", "gvcp.value",
 377         FT_UINT32, BASE_HEX,
 378         NULL, 0x0,
 379         NULL, HFILL }
 380     },
 381     { &hf_gvcp_address2,
 382       { "Address 2", "gvcp.address2",
 383         FT_UINT32, BASE_HEX,
 384         NULL, 0x0,
 385         NULL, HFILL }
 386     },
 387     { &hf_gvcp_value2,
 388       { "Value 2", "gvcp.value2",
 389         FT_UINT32, BASE_HEX,
 390         NULL, 0x0,
 391         NULL, HFILL }
 392     },
 393     { &hf_gvcp_remainder,
 394       { "Remaining arguments", "gvcp.remainder",
 395         FT_BYTES, BASE_NONE,
 396         NULL, 0x0,
 397         NULL, HFILL }
 398     },
 399     { &hf_gvcp_nwritten,
 400       { "Number of registers written", "gvcp.nwritten",
 401         FT_UINT32, BASE_DEC,
 402         NULL, 0x0,
 403         NULL, HFILL }
 404     },
 405     { &hf_gvcp_nbytes,
 406       { "Number of bytes", "gvcp.nbytes",
 407         FT_UINT32, BASE_DEC,
 408         NULL, 0x0,
 409         NULL, HFILL }
 410     },
 411     { &hf_gvcp_unknown16,
 412       { "2-byte unknown meaning", "gvcp.unknown16",
 413         FT_UINT16, BASE_HEX,
 414         NULL, 0x0,
 415         NULL, HFILL }
 416     },
 417     { &hf_gvcp_data,
 418       { "Data", "gvcp.data",
 419         FT_BYTES, BASE_NONE,
 420         NULL, 0x0,
 421         NULL, HFILL }
 422     },
 423     { &hf_gvcp_ether,
 424       { "Link layer address (ethernet)", "gvcp.ether",
 425         FT_ETHER, BASE_NONE,
 426         NULL, 0x0,
 427         NULL, HFILL }
 428     },
 429     { &hf_gvcp_ip,
 430       { "IPv4 address", "gvcp.ip",
 431         FT_IPv4, BASE_NONE,
 432         NULL, 0x0,
 433         NULL, HFILL }
 434     },
 435     { &hf_gvcp_netmask,
 436       { "Netmask", "gvcp.netmask",
 437         FT_IPv4, BASE_NONE,
 438         NULL, 0x0,
 439         NULL, HFILL }
 440     }
 441   };
 442
 443   /* Setup protocol subtree array */
 444   static gint *ett[] = {
 445     &ett_gvcp
 446   };
 447
 448   proto_gvcp = proto_register_protocol ("GigE Vision Control Protocol", /*name*/
 449                                         "GVCP",         /* short name */
 450                                         "gvcp"          /* abbrev     */);
 451
 452   proto_register_field_array(proto_gvcp, hf, array_length(hf));
 453   proto_register_subtree_array(ett, array_length(ett));
 454
 455 }
 456
 457 void
 458 proto_reg_handoff_gvcp(void)
 459 {
 460   dissector_handle_t gvcp_handle;
 461
 462   gvcp_handle = new_create_dissector_handle(dissect_gvcp, proto_gvcp);
 463   dissector_add_uint("udp.port", GVCP_PORT, gvcp_handle);
 464 }
 465