/* packet-cmstatus.c
 * Routines for DOCSIS 3.0 CM-STATUS Report Message dissection.
 * Copyright 2011, Hendrik Robbel <hendrik.robbel[AT]kabeldeutschland.de>
 *
 * $Id$
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "config.h"

#include <epan/packet.h>
#include <epan/exceptions.h>

#define SEC_CH_MDD_TIMEOUT      1
#define QAM_FEC_LOCK_FAILURE    2
#define SEQ_OUT_OF_RANGE        3
#define SEC_CH_MDD_RECOVERY     4
#define QAM_FEC_LOCK_RECOVERY   5
#define T4_TIMEOUT              6
#define T3_RETRIES_EXCEEDED     7
#define SUCCESS_RANGING_AFTER_T3_RETRIES_EXCEEDED 8
#define CM_ON_BATTERY           9
#define CM_ON_AC_POWER         10

#define EVENT_DESCR             2
#define EVENT_DS_CH_ID          4
#define EVENT_US_CH_ID          5
#define EVENT_DSID              6


/* Initialize the protocol and registered fields */
static int proto_docsis_cmstatus = -1;
static int hf_docsis_cmstatus_tranid = -1;
static int hf_docsis_cmstatus_e_t_mdd_t = -1;
static int hf_docsis_cmstatus_e_t_qfl_f = -1;
static int hf_docsis_cmstatus_e_t_s_o = -1;
static int hf_docsis_cmstatus_e_t_mdd_r = -1;
static int hf_docsis_cmstatus_e_t_qfl_r = -1;
static int hf_docsis_cmstatus_e_t_t4_t = -1;
static int hf_docsis_cmstatus_e_t_t3_e = -1;
static int hf_docsis_cmstatus_e_t_rng_s = -1;
static int hf_docsis_cmstatus_e_t_cm_b = -1;
static int hf_docsis_cmstatus_e_t_cm_a = -1;
static int hf_docsis_cmstatus_ds_ch_id = -1;
static int hf_docsis_cmstatus_us_ch_id = -1;
static int hf_docsis_cmstatus_dsid = -1;
static int hf_docsis_cmstatus_descr = -1;


/* Initialize the subtree pointers */
static gint ett_docsis_cmstatus = -1;
static gint ett_docsis_cmstatus_tlv = -1;

/* See Table 6-52 in CM-SP-MULPIv3.0-I14-101008 */
static void
dissect_cmstatus_tlv (tvbuff_t * tvb, proto_tree * tree, guint8 start, guint16 len)
{
  proto_item *it;
  proto_tree *tlv_tree;
  guint16 pos = start + 1;
  guint8 type, length;

  it = proto_tree_add_protocol_format (tree, proto_docsis_cmstatus, tvb, 0, len, "TLV Data");
  tlv_tree = proto_item_add_subtree (it, ett_docsis_cmstatus_tlv);

  while (pos < (len + start + 1))
  {
    length = tvb_get_guint8 (tvb, pos++);
    type = tvb_get_guint8 (tvb, pos++);
    switch (type)
    {
    case EVENT_DS_CH_ID:
      if (length == 3)
      {
        proto_tree_add_item (tlv_tree, hf_docsis_cmstatus_ds_ch_id, tvb, pos + 1, 1, ENC_BIG_ENDIAN);
      }
      else
      {
        THROW (ReportedBoundsError);
      }
      break;

    case EVENT_US_CH_ID:
      if (length == 3)
      {
        proto_tree_add_item (tlv_tree, hf_docsis_cmstatus_us_ch_id, tvb, pos + 1, 1, ENC_BIG_ENDIAN);
      }
      else
      {
        THROW (ReportedBoundsError);
      }
      break;

    case EVENT_DSID:
      if (length == 5)
      {
        proto_tree_add_item (tlv_tree, hf_docsis_cmstatus_dsid, tvb, pos + 1, 3, ENC_BIG_ENDIAN);
      }
      else
      {
        THROW (ReportedBoundsError);
      }
      break;

    case EVENT_DESCR:
      if (length >= 3 && length <= 82)
      {
        proto_tree_add_item (tlv_tree, hf_docsis_cmstatus_descr, tvb, pos + 1, length - 2, ENC_NA);
      }
      else
      {
        THROW (ReportedBoundsError);
      }
      break;
    } /* switch */
    pos = pos + length;
  } /* while */
}

static void
dissect_cmstatus (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
{
  proto_item *it;
  proto_tree *cmstatus_tree = NULL;
  guint16 transid;
  guint8 event_type;
  guint16 len;
  transid = tvb_get_ntohs (tvb, 0);
  event_type = tvb_get_guint8 (tvb, 2);
  len = tvb_reported_length_remaining (tvb, 3);
  col_add_fstr (pinfo->cinfo, COL_INFO, "CM-STATUS Report: Transaction ID = %u", transid);

  if (tree)
  {
    it = proto_tree_add_protocol_format (tree, proto_docsis_cmstatus, tvb, 0, -1, "CM-STATUS Report");
    cmstatus_tree = proto_item_add_subtree (it, ett_docsis_cmstatus);
    proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_tranid, tvb, 0, 2, ENC_BIG_ENDIAN);

    switch (event_type)
    {
    case SEC_CH_MDD_TIMEOUT:
      proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_e_t_mdd_t, tvb, 2, 1, ENC_BIG_ENDIAN);
      break;

    case QAM_FEC_LOCK_FAILURE:
      proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_e_t_qfl_f, tvb, 2, 1, ENC_BIG_ENDIAN);
      break;

    case SEQ_OUT_OF_RANGE:
      proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_e_t_s_o, tvb, 2, 1, ENC_BIG_ENDIAN);
      break;

    case SEC_CH_MDD_RECOVERY:
      proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_e_t_mdd_r, tvb, 2, 1, ENC_BIG_ENDIAN);
      break;

    case QAM_FEC_LOCK_RECOVERY:
      proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_e_t_qfl_r, tvb, 2, 1, ENC_BIG_ENDIAN);
      break;

    case T4_TIMEOUT:
      proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_e_t_t4_t, tvb, 2, 1, ENC_BIG_ENDIAN);
      break;

    case T3_RETRIES_EXCEEDED:
      proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_e_t_t3_e, tvb, 2, 1, ENC_BIG_ENDIAN);
      break;

    case SUCCESS_RANGING_AFTER_T3_RETRIES_EXCEEDED:
      proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_e_t_rng_s, tvb, 2, 1, ENC_BIG_ENDIAN);
      break;

    case CM_ON_BATTERY:
      proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_e_t_cm_b, tvb, 2, 1, ENC_BIG_ENDIAN);
      break;

    case CM_ON_AC_POWER:
      proto_tree_add_item (cmstatus_tree, hf_docsis_cmstatus_e_t_cm_a, tvb, 2, 1, ENC_BIG_ENDIAN);
      break;
    } /* switch */

  }
    /* Call Dissector TLV's */
  dissect_cmstatus_tlv(tvb, cmstatus_tree, 3, len);
}



/* Register the protocol with Wireshark */
/* this format is require because a script is used to build the C function
   that calls all the protocol registration. */

void
proto_register_docsis_cmstatus (void)
{
/* Setup list of header fields  See Section 1.6.1 for details*/
  static hf_register_info hf[] = {
    {&hf_docsis_cmstatus_tranid,
      {"Transaction ID", "docsis_cmstatus.tranid",FT_UINT16, BASE_DEC, NULL, 0x0,NULL, HFILL}
    },
    /* See Table 10-3 in CM-SP-MULPIv3.0-I14-101008 */

    {&hf_docsis_cmstatus_e_t_mdd_t,
      {"Secondary Channel MDD timeout", "docsis_cmstatus.mdd_timeout", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL}
    },
    {&hf_docsis_cmstatus_e_t_qfl_f,
      {"QAM/FEC lock failure", "docsis_cmstatus.qam_fec_lock_failure", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL}
    },
    {&hf_docsis_cmstatus_e_t_s_o,
      {"Sequence out-of-range", "docsis_cmstatus.sequence_out_of_range", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL}
    },
    {&hf_docsis_cmstatus_e_t_mdd_r,
      {"Secondary Channel MDD Recovery", "docsis_cmstatus.mdd_recovery", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL}
    },
    {&hf_docsis_cmstatus_e_t_qfl_r,
      {"QAM/FEC Lock Recovery", "docsis_cmstatus.qam_fec_lock_recovery", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL}
    },
    {&hf_docsis_cmstatus_e_t_t4_t,
      {"T4 timeout", "docsis_cmstatus.t4_timeout", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL}
    },
    {&hf_docsis_cmstatus_e_t_t3_e,
      {"T3 retries exceeded", "docsis_cmstatus.t3_retries_exceeded", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL}
    },
    {&hf_docsis_cmstatus_e_t_rng_s,
      {"Successful ranging after T3 retries exceeded", "docsis_cmstatus.successful_ranging_after_t3_retries_exceeded", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL}
    },
    {&hf_docsis_cmstatus_e_t_cm_b,
      {"CM operating on battery backup", "docsis_cmstatus.cm_on_battery", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL}
    },
    {&hf_docsis_cmstatus_e_t_cm_a,
      {"CM returned to A/C power", "docsis_cmstatus.cm_on_ac_power", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL}
    },
    {&hf_docsis_cmstatus_descr,
      {"1.2 Description", "docsis_cmstatus.description",FT_BYTES, BASE_NONE, NULL, 0x0,"Description", HFILL}
    },
    {&hf_docsis_cmstatus_ds_ch_id,
      {"1.4 Downstream Channel ID", "docsis_cmstatus.ds_chid",FT_UINT8, BASE_DEC, NULL, 0x0, "Downstream Channel ID", HFILL}
    },
    {&hf_docsis_cmstatus_us_ch_id,
      {"1.5 Upstream Channel ID", "docsis_cmstatus.us_chid",FT_UINT8, BASE_DEC, NULL, 0x0, "Upstream Channel ID", HFILL}
    },
    {&hf_docsis_cmstatus_dsid,
      {"1.6 DSID", "docsis_cmstatus.dsid", FT_UINT24, BASE_DEC, NULL, 0x0, "DSID", HFILL}
    }
  };

/* Setup protocol subtree array */
static gint *ett[] = {
  &ett_docsis_cmstatus,
  &ett_docsis_cmstatus_tlv
};

/* Register the protocol name and description */
  proto_docsis_cmstatus = proto_register_protocol ("DOCSIS CM-STATUS Report", "DOCSIS CM-STATUS", "docsis_cmstatus");

/* Required function calls to register the header fields and subtrees used */
  proto_register_field_array (proto_docsis_cmstatus, hf, array_length (hf));
  proto_register_subtree_array (ett, array_length (ett));
  register_dissector ("docsis_cmstatus", dissect_cmstatus, proto_docsis_cmstatus);
}


/* If this dissector uses sub-dissector registration add a registration routine.
   This format is required because a script is used to find these routines and
   create the code that calls these routines.
*/
void
proto_reg_handoff_docsis_cmstatus (void)
{
  dissector_handle_t docsis_cmstatus_handle;
  docsis_cmstatus_handle = find_dissector ("docsis_cmstatus");
  dissector_add_uint ("docsis_mgmt", 0x29, docsis_cmstatus_handle);
}
