/* wimax_harq_map_decoder.c * WiMax HARQ Map Message decoder * * Copyright (c) 2007 by Intel Corporation. * * Author: Lu Pan * * $Id$ * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1999 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* Include files */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include "crc.h" extern guint wimax_compact_dlmap_ie_decoder(proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, guint offset, guint nibble_offset); extern guint wimax_compact_ulmap_ie_decoder(proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, guint offset, guint nibble_offset); extern gint proto_wimax; /* forward reference */ void dissector_wimax_harq_map_decoder(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree); static gint proto_wimax_harq_map_decoder = -1; static gint ett_wimax_harq_map_decoder = -1; /* MASKs */ #define LSB_NIBBLE_MASK 0x0F /* HARQ MAP masks */ #define WIMAX_HARQ_MAP_INDICATOR_MASK 0xE00000 #define WIMAX_HARQ_UL_MAP_APPENDED_MASK 0x100000 #define WIMAX_HARQ_MAP_RESERVED_MASK 0x080000 #define WIMAX_HARQ_MAP_MSG_LENGTH_MASK 0x07FC00 #define WIMAX_HARQ_MAP_DL_IE_COUNT_MASK 0x0003F0 #define WIMAX_HARQ_MAP_MSG_LENGTH_SHIFT 10 #define WIMAX_HARQ_MAP_DL_IE_COUNT_SHIFT 4 /* HARQ MAP display indexies */ static gint hf_harq_map_indicator = -1; static gint hf_harq_ul_map_appended = -1; static gint hf_harq_map_reserved = -1; static gint hf_harq_map_msg_length = -1; static gint hf_harq_dl_ie_count = -1; static gint hf_harq_map_msg_crc = -1; /* HARQ MAP message decoder */ void dissector_wimax_harq_map_decoder(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { guint i, offset = 0; guint tvb_len, length, dl_ie_count; guint ie_length; proto_item *harq_map_item = NULL; proto_tree *harq_map_tree = NULL; guint nibble_offset; proto_item *parent_item = NULL; proto_item *it = NULL; guint ulmap_appended; guint32 harq_map_msg_crc, calculated_crc; guint32 first_24bits; /* check the tvb reported length */ tvb_len = tvb_reported_length(tvb); if(!tvb_len) { /* do nothing if tvb is empty */ return; } /* Ensure the right payload type */ first_24bits = tvb_get_ntoh24(tvb, offset); if((first_24bits & WIMAX_HARQ_MAP_INDICATOR_MASK) != WIMAX_HARQ_MAP_INDICATOR_MASK) { /* do nothing if tvb is not a HARQ MAP message */ return; } /* update the info column */ col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, "HARQ-MAP Message: "); if (tree) { /* we are being asked for details */ /* get the parent */ parent_item = proto_tree_get_parent(tree); /* display HARQ-MAP Message and create subtree */ harq_map_item = proto_tree_add_protocol_format(tree, proto_wimax_harq_map_decoder, tvb, offset, tvb_len, "HARQ-MAP Message (%u bytes)", tvb_len); harq_map_tree = proto_item_add_subtree(harq_map_item, ett_wimax_harq_map_decoder); /* display the HARQ MAP Indicator */ proto_tree_add_item(harq_map_tree, hf_harq_map_indicator, tvb, offset, 3, FALSE); /* display the HARQ MAp UL-MAP Appended */ proto_tree_add_item(harq_map_tree, hf_harq_ul_map_appended, tvb, offset, 3, FALSE); /* display the reserved bit */ proto_tree_add_item(harq_map_tree, hf_harq_map_reserved, tvb, offset, 3, FALSE); /* display the HARQ MAP message length */ proto_tree_add_item(harq_map_tree, hf_harq_map_msg_length, tvb, offset, 3, FALSE); /* display the DL IE count */ proto_tree_add_item(harq_map_tree, hf_harq_dl_ie_count, tvb, offset, 3, FALSE); /* get the message length */ length = ((first_24bits & WIMAX_HARQ_MAP_MSG_LENGTH_MASK) >> WIMAX_HARQ_MAP_MSG_LENGTH_SHIFT); /* get the DL IE count */ dl_ie_count = ((first_24bits & WIMAX_HARQ_MAP_DL_IE_COUNT_MASK) >> WIMAX_HARQ_MAP_DL_IE_COUNT_SHIFT); /* get the UL MAP appended */ ulmap_appended = (first_24bits & WIMAX_HARQ_UL_MAP_APPENDED_MASK); if (parent_item == NULL || PITEM_FINFO(parent_item) == NULL) { parent_item = harq_map_item; /* Prevent crash */ } /* set the offsets to Compact DL-MAP IEs */ offset += 2; nibble_offset = 1; /* process the compact dl_map ies */ for(i=0; i> 1); nibble_offset = ((nibble_offset + ie_length) & 1); } /* check if there exist the compact ul_map IEs */ if (ulmap_appended) { /* add the UL-MAp IEs info */ proto_item_append_text(parent_item, ",UL-MAP IEs"); /* process the compact ul_map ies */ while(offset < (length - sizeof(harq_map_msg_crc))) { /* decode Compact UL-MAP IEs */ ie_length = wimax_compact_ulmap_ie_decoder(harq_map_tree, pinfo, tvb, offset, nibble_offset); /* Prevent endless loop with erroneous data. */ if (ie_length < 2) ie_length = 2; offset += ((nibble_offset + ie_length) >> 1); nibble_offset = ((nibble_offset + ie_length) & 1); } } /* handle the padding */ if(nibble_offset) { /* add the Padding info */ proto_item_append_text(parent_item, ",Padding"); proto_tree_add_protocol_format(harq_map_tree, proto_wimax_harq_map_decoder, tvb, offset, 1, "Padding Nibble: 0x%x", (tvb_get_guint8(tvb, offset) & LSB_NIBBLE_MASK)); } /* add the CRC info */ proto_item_append_text(parent_item, ",CRC"); /* get the CRC */ harq_map_msg_crc = tvb_get_ntohl(tvb, length - sizeof(harq_map_msg_crc)); /* calculate the HARQ MAM Message CRC */ calculated_crc = wimax_mac_calc_crc32(tvb_get_ptr(tvb, 0, length - sizeof(harq_map_msg_crc)), length - sizeof(harq_map_msg_crc)); /* display the CRC */ it = proto_tree_add_item(harq_map_tree, hf_harq_map_msg_crc, tvb, length - sizeof(harq_map_msg_crc), sizeof(harq_map_msg_crc), FALSE); /* verify the CRC */ if (harq_map_msg_crc != calculated_crc) { proto_item_append_text(it, " - incorrect! (should be: 0x%x)", calculated_crc); } } } /* Register Wimax HARQ MAP Protocol */ void proto_register_wimax_harq_map(void) { /* HARQ MAP display */ static hf_register_info hf_harq_map[] = { { &hf_harq_map_indicator, {"HARQ MAP Indicator", "wmx.harq_map.indicator", FT_UINT24, BASE_HEX, NULL, WIMAX_HARQ_MAP_INDICATOR_MASK, NULL, HFILL} }, { &hf_harq_ul_map_appended, {"HARQ UL-MAP Appended", "wmx.harq_map.ul_map_appended", FT_UINT24, BASE_HEX, NULL, WIMAX_HARQ_UL_MAP_APPENDED_MASK, NULL, HFILL} }, { &hf_harq_map_reserved, {"Reserved", "wmx.harq_map.reserved", FT_UINT24, BASE_HEX, NULL, WIMAX_HARQ_MAP_RESERVED_MASK, NULL, HFILL} }, { &hf_harq_map_msg_length, {"Map Message Length", "wmx.harq_map.msg_length", FT_UINT24, BASE_DEC, NULL, WIMAX_HARQ_MAP_MSG_LENGTH_MASK, NULL, HFILL} }, { &hf_harq_dl_ie_count, {"DL IE Count", "wmx.harq_map.dl_ie_count", FT_UINT24, BASE_DEC, NULL, WIMAX_HARQ_MAP_DL_IE_COUNT_MASK, NULL, HFILL} }, { &hf_harq_map_msg_crc, {"HARQ MAP Message CRC", "wmx.harq_map.msg_crc", FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL} } }; /* Setup protocol subtree array */ static gint *ett[] = { &ett_wimax_harq_map_decoder, }; proto_wimax_harq_map_decoder = proto_wimax; proto_register_subtree_array(ett, array_length(ett)); proto_register_field_array(proto_wimax_harq_map_decoder, hf_harq_map, array_length(hf_harq_map)); }