/* packet-mpeg1.c

 *

 * Routines for RFC 2250 MPEG-1 dissection

 *

 * Copyright 2001,

 * Francisco Javier Cabello Torres, <fjcabello@vtools.es>

 *

 * Wireshark - Network traffic analyzer

 * By Gerald Combs <gerald@wireshark.org>

 * Copyright 1998 Gerald Combs

 *

 * SPDX-License-Identifier: GPL-2.0-or-later

 */

/*

 * This dissector tries to dissect the MPEG-1 video streams.

 */

#include "config.h"

#include <epan/packet.h>

#include "packet-rtp_pt.h"

void proto_register_mpeg1(void);

void proto_reg_handoff_mpeg1(void);

static dissector_handle_t mpeg1_handle;

/* MPEG1 header fields             */

static int proto_mpg;

static int hf_rtp_mpg_mbz;

static int hf_rtp_mpg_T;

static int hf_rtp_mpg_tr;

static int hf_rtp_mpg_an;

static int hf_rtp_mpg_n;

static int hf_rtp_mpg_s;

static int hf_rtp_mpg_b;

static int hf_rtp_mpg_e;

static int hf_rtp_mpg_p;

static int hf_rtp_mpg_fbv;

static int hf_rtp_mpg_bfc;

static int hf_rtp_mpg_ffv;

static int hf_rtp_mpg_ffc;

static int hf_rtp_mpg_data;

/* MPEG-1 fields defining a sub tree */

static int ett_mpg;

static const value_string rtp_mpg_picture_types_vals[] =

{

  { 0, "Forbidden" },

  { 1, "I-Picture" },

  { 2, "P-Picture" },

  { 3, "B-Picture" },

  { 4, "D-Picture" },

  { 5, "reserved" },

  { 6, "reserved" },

  { 7, "reserved" },

  { 0, NULL },

};

static int

dissect_mpeg1( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_ )

{

  proto_item *ti;

  proto_tree *mpg_tree;

  unsigned int offset       = 0;

  static int * const mpg_fields1[] = {

    &hf_rtp_mpg_mbz,

    &hf_rtp_mpg_T,

    &hf_rtp_mpg_tr,

    NULL

  };

  static int * const mpg_fields2[] = {

    &hf_rtp_mpg_an,

    &hf_rtp_mpg_n,

    &hf_rtp_mpg_s,

    &hf_rtp_mpg_b,

    &hf_rtp_mpg_e,

    &hf_rtp_mpg_p,

    NULL

  };

  static int * const mpg_fields3[] = {

    &hf_rtp_mpg_fbv,

    &hf_rtp_mpg_bfc,

    &hf_rtp_mpg_ffv,

    &hf_rtp_mpg_ffc,

    NULL

  };

  col_set_str(pinfo->cinfo, COL_PROTOCOL, "MPEG-1");

  col_set_str(pinfo->cinfo, COL_INFO, "MPEG-1 message");

  /* Get MPEG-1  fields */

  ti = proto_tree_add_item( tree, proto_mpg, tvb, offset, -1, ENC_NA );

  mpg_tree = proto_item_add_subtree( ti, ett_mpg );

  proto_tree_add_bitmask_list(mpg_tree, tvb, offset, 2, mpg_fields1, ENC_BIG_ENDIAN);

  offset += 2;

  proto_tree_add_bitmask_list(mpg_tree, tvb, offset, 2, mpg_fields2, ENC_BIG_ENDIAN);

  offset += 1;

  proto_tree_add_bitmask_list(mpg_tree, tvb, offset, 1, mpg_fields3, ENC_NA);

  offset += 1;

  /* The rest of the packet is the MPEG-1 stream */

  proto_tree_add_item( mpg_tree, hf_rtp_mpg_data, tvb, offset, -1, ENC_NA );

  return tvb_captured_length(tvb);

}

void

proto_register_mpeg1(void)

{

  static hf_register_info hf[] =

  {

    {

      &hf_rtp_mpg_mbz,

      {

        "MBZ",

        "rtp.payload_mpeg_mbz",

        FT_UINT16,

        BASE_DEC,

        NULL,

        0xF800,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_T,

      {

        "T",

        "rtp.payload_mpeg_T",

        FT_UINT16,

        BASE_DEC,

        NULL,

        0x0400,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_tr,

      {

        "Temporal Reference",

        "rtp.payload_mpeg_tr",

        FT_UINT16,

        BASE_DEC,

        NULL,

        0x03FF,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_an,

      {

        "AN",

        "rtp.payload_mpeg_an",

        FT_UINT16,

        BASE_DEC,

        NULL,

        0x80,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_n,

      {

        "New Picture Header",

        "rtp.payload_mpeg_n",

        FT_UINT16,

        BASE_DEC,

        NULL,

        0x40,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_s,

      {

        "Sequence Header",

        "rtp.payload_mpeg_s",

        FT_BOOLEAN,

        16,

        NULL,

        0x0020,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_b,

      {

        "Beginning-of-slice",

        "rtp.payload_mpeg_b",

        FT_BOOLEAN,

        16,

        NULL,

        0x0010,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_e,

      {

        "End-of-slice",

        "rtp.payload_mpeg_e",

        FT_BOOLEAN,

        16,

        NULL,

        0x0008,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_p,

      {

        "Picture type",

        "rtp.payload_mpeg_p",

        FT_UINT16,

        BASE_DEC,

        VALS(rtp_mpg_picture_types_vals),

        0x07,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_fbv,

      {

        "FBV",

        "rtp.payload_mpeg_fbv",

        FT_UINT16,

        BASE_DEC,

        NULL,

        0x80,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_bfc,

      {

        "BFC",

        "rtp.payload_mpeg_bfc",

        FT_UINT16,

        BASE_DEC,

        NULL,

        0x70,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_ffv,

      {

        "FFV",

        "rtp.payload_mpeg_ffv",

        FT_UINT16,

        BASE_DEC,

        NULL,

        0x08,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_ffc,

      {

        "FFC",

        "rtp.payload_mpeg_ffc",

        FT_UINT16,

        BASE_DEC,

        NULL,

        0x07,

        NULL, HFILL

      }

    },

    {

      &hf_rtp_mpg_data,

      {

        "MPEG-1 stream",

        "mpeg1.stream",

        FT_BYTES,

        BASE_NONE,

        NULL,

        0x0,

        NULL, HFILL

      }

    },

  };

  static int *ett[] =

  {

    &ett_mpg,

  };

  proto_mpg = proto_register_protocol("RFC 2250 MPEG1","MPEG1","mpeg1");

  mpeg1_handle = register_dissector("mpeg1", dissect_mpeg1, proto_mpg);

  proto_register_field_array(proto_mpg, hf, array_length(hf));

  proto_register_subtree_array(ett, array_length(ett));

}

void

proto_reg_handoff_mpeg1(void)

{

  dissector_add_uint("rtp.pt", PT_MPV, mpeg1_handle);

}

/*

 * Editor modelines  -  https://www.wireshark.org/tools/modelines.html

 *

 * Local variables:

 * c-basic-offset: 8

 * tab-width: 8

 * indent-tabs-mode: t

 * End:

 *

 * vi: set shiftwidth=8 tabstop=8 noexpandtab:

 * :indentSize=8:tabSize=8:noTabs=false:

 */