Start of a Radio Signalling Link (RSL) dissector (3GPP TS 48.058).

svn path=/trunk/; revision=22919

1 files changed, 897 insertions, 0 deletions

diff --git a/epan/dissectors/packet-rsl.c b/epan/dissectors/packet-rsl.c
new file mode 100644
index 0000000000..ea777548b1
--- /dev/null
+++ b/epan/dissectors/packet-rsl.c
@@ -0,0 +1,897 @@
+/* packet-rsl.c
+ * Routines for Radio Signalling Link (RSL) dissection.
+ *
+ * Copyright 2007, Anders Broman <anders.broman@ericsson.com>
+ *
+ * $Id$
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * Copied from packet-cops.c
+ *
+ * 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.
+ *
+ * REF: 3GPP TS 48.058 version 6.1.0 Release 6 
+ * http://www.3gpp.org/ftp/Specs/html-info/48058.htm
+ * 
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+#include <epan/packet.h>
+#include <epan/proto.h>
+#include <epan/lapd_sapi.h>
+
+/* Initialize the protocol and registered fields */
+static int proto_rsl		= -1;
+
+static int hf_rsl_msg_type			= -1;
+static int hf_rsl_T_bit				= -1;
+static int hf_rsl_msg_dsc			= -1;
+static int hf_rsl_ie_id				= -1;
+static int hf_rsl_ie_length			= -1;
+static int hf_rsl_ch_no_Cbits		= -1;
+static int hf_rsl_ch_no_TN			= -1;
+
+static int hf_rsl_acc_delay			= -1;
+static int hf_rsl_req_ref_ra		= -1;
+static int hf_rsl_req_ref_T1prim	= -1;
+static int hf_rsl_req_ref_T3		= -1;
+static int hf_rsl_req_ref_T2		= -1;
+static int hf_rsl_phy_ctx			= -1;
+static int hf_rsl_na				= -1;
+static int hf_rsl_ch_type			= -1;
+static int hf_rsl_prio				= -1;
+static int hf_rsl_sapi				= -1;
+static int hf_rsl_cause				= -1;
+static int hf_rsl_rel_mode			= -1;
+
+/* Initialize the subtree pointers */
+static int ett_rsl = -1;
+static int ett_ie_ch_no = -1;
+static int ett_ie_phy_ctx = -1;
+static int ett_ie_access_delay = -1;
+static int ett_ie_req_ref = -1;
+static int ett_ie_full_imm_ass_inf = -1;
+
+proto_tree *top_tree;
+dissector_handle_t gsm_a_ccch_handle = NULL;
+dissector_handle_t gsm_a_dtap_handle = NULL;
+
+static const true_false_string rsl_t_bit_vals = {
+  "Considered transparent by BTS",
+  "Not considered transparent by BTS"
+};
+
+static const true_false_string rsl_na_vals = {
+  "Applicable",
+  "Not Applicable"
+};
+
+
+/*
+ * 9.1 Message discriminator
+ */
+static const value_string rsl_msg_disc_vals[] = {
+	{  0x00,		"Reserved" },
+	{  0x01,		"Radio Link Layer Management messages" },
+	{  0x04,		"Dedicated Channel Management messages" },
+	{  0x06,		"Common Channel Management messages" },
+	{  0x08,		"TRX Management messages" },
+	{  0x16,		"Location Services messages" },
+	{ 0,			NULL }
+};
+/*
+ * 9.2 MESSAGE TYPE
+ */
+#define RSL_MSG_TYPE_DATA_REQ	1
+#define RSL_MSG_TYPE_DATA_IND	2
+#define RSL_MSG_TYPE_ERROR_IND	3
+#define RSL_MSG_TYPE_EST_REQ	4
+#define RSL_MSG_TYPE_EST_CONF	5
+#define RSL_MSG_EST_IND			6
+#define RSL_MSG_REL_REQ			7
+#define RSL_MSG_REL_CONF		8
+#define RSL_MSG_REL_IND			9
+#define RSL_MSG_UNIT_DATA_REQ	10
+
+#define RSL_MSG_CHANRQD			19
+#define RSL_MSG_IMM_ASS_CMD		22
+static const value_string rsl_msg_type_vals[] = {
+	  /* 	0 0 0 0 - - - - Radio Link Layer Management messages: */
+	{  0x01,	"DATA REQuest" },								/* 8.3.1 */
+	{  0x02,	"DATA INDication" },							/* 8.3.2 */
+	{  0x03,	"ERROR INDication" },							/* 8.3.3 */
+	{  0x04,	"ESTablish REQuest" },							/* 8.3.4 */
+	{  0x05,	"ESTablish CONFirm" },							/* 8.3.5 */
+	{  0x06,	"ESTablish INDication" },						/* 8.3.6 */
+	{  0x07,	"RELease REQuest" },							/* 8.3.7 */
+	{  0x08,	"RELease CONFirm" },							/* 8.3.8 */
+	{  0x09,	"RELease INDication" },							/* 8.3.9 */
+	{  0x0a,	"UNIT DATA REQuest" },							/* 8.3.10 */
+	/* 0 0 0 1 - - - - Common Channel Management/TRX Management messages: */
+	{  0x11,	"BCCH INFOrmation" },							/* 8.5.1 */
+	{  0x12,	"CCCH LOAD INDication" },						/* 8.5.2 */
+	{  0x13,	"CHANnel ReQuireD" },							/* 8.5.3 */
+	{  0x14,	"DELETE INDication" },							/* 8.5.4 */
+	{  0x15,	"PAGING CoMmanD" },								/* 8.5.5 */
+	{  0x16,	"IMMEDIATE ASSIGN COMMAND" },					/* 8.5.6 */
+	{  0x17,	"SMS BroadCast REQuest" },						/* 8.5.7 */
+	{  0x18,	"RF RESource INDication" },						/* 8.6.1 */
+	{  0x19,	"SACCH FILLing" },								/* 8.6.2 */
+	{  0x1b,	"OVERLOAD" },									/* 8.6.3 */
+	{  0x1c,	"ERROR REPORT" },								/* 8.6.4 */
+	{  0x1d,	"SMS BroadCast CoMmanD" },						/* 8.5.8 */
+	{  0x1e,	"CBCH LOAD INDication" },						/* 8.5.9 */
+	{  0x1f,	"NOTification CoMmanD" },						/* 8.5.10 */
+	/* 0 0 1 - - - - - Dedicated Channel Management messages: */
+	{  0x21,	"CHANnel ACTIVation" },							/* 8.4.1 */
+	{  0x22,	"CHANnel ACTIVation ACKnowledge" },				/* 8.4.2 */
+	{  0x23,	"CHANnel ACTIVation Negative ACK" },			/* 8.4.3 */
+	{  0x24,	"CONNection FAILure" },							/* 8.4.4 */
+	{  0x25,	"DEACTIVATE SACCH" },							/* 8.4.5 */
+	{  0x26,	"ENCRyption CoMmanD" },							/* 8.4.6 */
+	{  0x27,	"HANDOver DETection" },							/* 8.4.7 */
+	{  0x28,	"MEASurement RESult" },							/* 8.4.8 */
+	{  0x29,	"MODE MODIFY REQuest" },						/* 8.4.9 */
+	{  0x2a,	"MODE MODIFY ACKnowledge" },					/* 8.4.10 */
+	{  0x2b,	"MODE MODIFY Negative ACKnowledge" },			/* 8.4.11 */
+	{  0x2c,	"PHYsical CONTEXT REQuest" },					/* 8.4.12 */
+	{  0x2d,	"PHYsical CONTEXT CONFirm" },					/* 8.4.13 */
+	{  0x2e,	"RF CHANnel RELease" },							/* 8.4.14 */
+	{  0x2f,	"MS POWER CONTROL" },							/* 8.4.15 */
+	{  0x30,	"BS POWER CONTROL" },							/* 8.4.16 */
+	{  0x31,	"PREPROCess CONFIGure" },						/* 8.4.17 */
+	{  0x32,	"PREPROCessed MEASurement RESult" },			/* 8.4.18 */
+	{  0x33,	"RF CHANnel RELease ACKnowledge" },				/* 8.4.19 */
+	{  0x34,	"SACCH INFO MODIFY" },							/* 8.4.20 */
+	{  0x35,	"TALKER DETection" },							/* 8.4.21 */
+	{  0x36,	"LISTENER DETection" },							/* 8.4.22 */
+	{  0x37,	"REMOTE CODEC CONFiguration REPort" },			/* 8.4.23 */
+	{  0x38,	"Round Trip Delay REPort" },					/* 8.4.24 */
+	{  0x39,	"PRE-HANDOver NOTIFication" },					/* 8.4.25 */
+	{  0x3a,	"MultiRate CODEC MODification REQest" },		/* 8.4.26 */
+	{  0x3b,	"MultiRate CODEC MOD ACKnowledge" },			/* 8.4.27 */
+	{  0x3c,	"MultiRate CODEC MOD Negative ACKnowledge" },	/* 8.4.28 */
+	{  0x3d,	"MultiRate CODEC MOD PERformed" },				/* 8.4.29 */
+	{  0x3e,	"TFO REPort" },									/* 8.4.30 */
+	{  0x3f,	"TFO MODification REQuest" },					/* 8.4.31 */
+	/* 	0 1 - - - - - - Location Services messages: */
+	{  0x41,	"Location Information" },						/* 8.7.1 */
+	{ 0,		NULL }
+};
+
+
+static const value_string rsl_ie_type_vals[] = {
+	{  0x01,	"Channel Number" },				/*  9.3.1 */
+	{  0x02,	"Link Identifier" },			/*  9.3.2 */
+	{  0x03,	"Activation Type" },			/*  9.3.3 */
+	{  0x04,	"BS Power" },					/*  9.3.4 */
+	{  0x05,	"Channel Identification" },		/*  9.3.5 */
+	{  0x06,	"Channel Mode" },				/*  9.3.6 */
+	{  0x07,	"Encryption Information" },		/*  9.3.7 */
+	{  0x08,	"Frame Number" },				/*  9.3.8 */
+	{  0x09,	"Handover Reference" },			/*  9.3.9 */
+	{  0x0a,	"L1 Information" },				/*  9.3.10 */
+	{  0x0b,	"L3 Information" },				/*  9.3.11 */
+	{  0x0c,	"MS Identity" },				/*  9.3.12 */
+	{  0x0d,	"MS Power" },					/*  9.3.13 */
+	{  0x0e,	"Paging Group" },				/*  9.3.14 */
+	{  0x0f,	"Paging Load" },				/*  9.3.15 */
+	{  0x10,	"Physical Context" },			/*  9.3.16 */
+	{  0x11,	"Access Delay" },				/*  9.3.17 */
+	{  0x12,	"RACH Load" },					/*  9.3.18 */
+	{  0x13,	"Request Reference" },			/*  9.3.19 */
+	{  0x14,	"Release Mode" },				/*  9.3.20 */
+	{  0x15,	"Resource Information" },		/*  9.3.21 */
+	{  0x16,	"RLM Cause" },					/*  9.3.22 */
+	{  0x17,	"Starting Time" },				/*  9.3.23 */
+	{  0x18,	"Timing Advance" },				/*  9.3.24 */
+	{  0x19,	"Uplink Measurements" },		/*  9.3.25 */
+	{  0x1a,	"Cause" },						/*  9.3.26 */
+	{  0x1b,	"Measurement result number" },	/*  9.3.27 */
+	{  0x1c,	"Message Identifier" },			/*  9.3.28 */
+	{  0x1d,	"reserved" },					/*  */
+	{  0x1e,	"System Info Type" },			/*  9.3.30 */
+	{  0x1f,	"MS Power Parameters" },		/*  9.3.31 */
+	{  0x20,	"BS Power Parameters" },		/*  9.3.32 */
+	{  0x21,	"Pre-processing Parameters" },	/*  9.3.33 */
+	{  0x22,	"Pre-processed Measurements" },	/*  9.3.34 */
+	{  0x23,	"reserved" },					/*  */
+	{  0x24,	"SMSCB Information" },			/*  9.3.36 */
+	{  0x25,	"MS Timing Offset" },			/*  9.3.37 */
+	{  0x26,	"Erroneous Message" },			/*  9.3.38 */
+	{  0x27,	"Full BCCH Information" },		/*  9.3.39 */
+	{  0x28,	"Channel Needed" },				/*  9.3.40 */
+	{  0x29,	"CB Command type" },			/*  9.3.41 */
+	{  0x2a,	"SMSCB message" },				/*  9.3.42 */
+	{  0x2b,	"Full Immediate Assign Info" },	/*  9.3.35 */
+	{  0x2c,	"SACCH Information" },			/*  9.3.29 */
+	{  0x2d,	"CBCH Load Information" },		/*  9.3.43 */
+	{  0x2e,	"SMSCB Channel Indicator" },	/*  9.3.44 */
+	{  0x2f,	"Group call reference" },		/*  9.3.45 */
+	{  0x30,	"Channel description" },		/*  9.3.46 */
+	{  0x31,	"NCH DRX information" },		/*  9.3.47 */
+	{  0x32,	"Command indicator" },			/*  9.3.48 */
+	{  0x33,	"eMLPP Priority" },				/*  9.3.49 */
+	{  0x34,	"UIC" },						/*  9.3.50 */
+	{  0x35,	"Main channel reference" },		/*  9.3.51 */
+	{  0x36,	"MultiRate configuration" },	/*  9.3.52 */
+	{  0x37,	"MultiRate Control" },			/*  9.3.53 */
+	{  0x38,	"Supported Codec Types" },		/*  9.3.54 */
+	{  0x39,	"Codec Configuration" },		/*  9.3.55 */
+	{  0x3a,	"Round Trip Delay" },			/*  9.3.56 */
+	{  0x3b,	"TFO Status" },					/*  9.3.57 */
+	{  0x3c,	"LLP APDU" },					/*  9.3.58 */
+	{  0x3d,	"TFO transparent container" },	/*  9.3.59 */
+	/*
+			0 0 1 1 1 1 1 0
+			to 
+			1 1 1 0 1 1 1 1
+			Reserved for future use
+			
+			1 1 1 1 0 0 0 0
+			to 
+			1 1 1 1 1 1 1 1
+			Not used
+			
+	*/
+	{ 0,			NULL }
+};
+
+
+/*
+C5	C4	C3	C2	C1
+0	0	0	0	1	Bm + ACCH's
+0	0	0	1	T	Lm + ACCH's
+0	0	1	T	T	SDCCH/4 + ACCH
+0	1	T	T	T	SDCCH/8 + ACCH
+1	0	0	0	0	BCCH
+1	0	0	0	1	Uplink CCCH (RACH)
+1	0	0	1	0	Downlink CCCH (PCH + AGCH)
+*/
+static const value_string rsl_ch_no_Cbits_vals[] = {
+	{  0x01,	"Bm + ACCH's" },
+	{  0x03,	"Lm + ACCH's" },
+	{  0x03,	"Lm + ACCH's" },
+	{  0x04,	"SDCCH/4 + ACCH" },
+	{  0x05,	"SDCCH/4 + ACCH" },
+	{  0x06,	"SDCCH/4 + ACCH" },
+	{  0x07,	"SDCCH/4 + ACCH" },
+	{  0x08,	"SDCCH/8 + ACCH" },
+	{  0x09,	"SDCCH/8 + ACCH" },
+	{  0x0a,	"SDCCH/8 + ACCH" },
+	{  0x0b,	"SDCCH/8 + ACCH" },
+	{  0x0c,	"SDCCH/8 + ACCH" },
+	{  0x0d,	"SDCCH/8 + ACCH" },
+	{  0x0e,	"SDCCH/8 + ACCH" },
+	{  0x0f,	"SDCCH/8 + ACCH" },
+	{  0x10,	"BCCH" },
+	{  0x11,	"Uplink CCCH (RACH)" },
+	{  0x12,	"Downlink CCCH (PCH + AGCH)" },
+	{ 0,			NULL }
+};
+/* 9.3.1 Channel number			9.3.1	M TV 2 */
+static int
+dissect_rsl_ie_ch_no(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+	proto_item *ti;
+	proto_tree *ie_tree;
+
+	ti = proto_tree_add_text(tree, tvb,offset,2,"Channel number IE ");
+	ie_tree = proto_item_add_subtree(ti, ett_ie_ch_no);
+
+
+	/* Element identifier */
+	proto_tree_add_item(ie_tree, hf_rsl_ie_id, tvb, offset, 1, FALSE);
+	offset++;
+	/* C-bits */
+	proto_tree_add_item(ie_tree, hf_rsl_ch_no_Cbits, tvb, offset, 1, FALSE);
+	/* TN is time slot number, binary represented as in 3GPP TS 45.002.
+	 * 3 Bits
+	 */
+	proto_tree_add_item(ie_tree, hf_rsl_ch_no_TN, tvb, offset, 1, FALSE);
+	offset++;
+	return offset;
+}
+
+static const value_string rsl_ch_type_vals[] = {
+	{  0x00,	"Main signalling channel (FACCH or SDCCH)" },
+	{  0x01,	"SACCH" },
+	{ 0,			NULL }
+};
+
+static const value_string rsl_prio_vals[] = {
+	{  0x00,	"Normal Priority" },
+	{  0x01,	"High Priority" },
+	{  0x02,	"Low Priority" },
+	{ 0,			NULL }
+};
+
+/*
+ * 9.3.2 Link Identifier M TV 2
+ */
+static int
+dissect_rsl_ie_link_id(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+	proto_item *ti;
+	proto_tree *ie_tree;
+	guint8 octet;
+
+	ti = proto_tree_add_text(tree, tvb,offset,2,"Link Identifier IE ");
+	ie_tree = proto_item_add_subtree(ti, ett_ie_phy_ctx);
+
+	/* Element identifier */
+	proto_tree_add_item(ie_tree, hf_rsl_ie_id, tvb, offset, 1, FALSE);
+	offset++;
+
+	octet = tvb_get_guint8(tvb,offset);
+
+	if(octet&0x20 == 0x20){
+		/* Not applicable */
+		proto_tree_add_item(ie_tree, hf_rsl_na, tvb, offset, 1, FALSE);
+		return offset++;
+	}
+	/* channel type */
+	proto_tree_add_item(ie_tree, hf_rsl_ch_type, tvb, offset, 1, FALSE);
+	/* NA - Not applicable */
+	proto_tree_add_item(ie_tree, hf_rsl_na, tvb, offset, 1, FALSE);
+	/* Priority */
+	proto_tree_add_item(ie_tree, hf_rsl_prio, tvb, offset, 1, FALSE);
+	/* SAPI 	 
+	 * The SAPI field contains the SAPI value as defined in 3GPP TS 44.005.
+	 */
+	proto_tree_add_item(ie_tree, hf_rsl_sapi, tvb, offset, 1, FALSE);
+	offset++;
+
+	return offset;
+}
+
+/*
+ * 9.3.11 L3 Information			9.3.11	M TLV >=3
+ *
+ * This element contains a link layer service data unit (L3 message).
+ * It is used to forward a complete L3 message as specified in 
+ * 3GPP TS 24.008 or 3GPP TS 44.018 between BTS and BSC.
+ */
+static int
+dissect_rsl_ie_L3_inf(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+	proto_item *ti;
+	proto_tree *ie_tree;
+	tvbuff_t	*next_tvb;
+	guint16 length;
+
+	ti = proto_tree_add_text(tree, tvb,offset,0,"L3 Information ");
+	ie_tree = proto_item_add_subtree(ti, ett_ie_phy_ctx);
+
+	/* Element identifier */
+	proto_tree_add_item(ie_tree, hf_rsl_ie_id, tvb, offset, 1, FALSE);
+	offset++;
+	/* Length */
+	length = tvb_get_ntohs(tvb, offset);
+	proto_item_set_len(ti, length+2);
+	proto_tree_add_item(ie_tree, hf_rsl_ie_length, tvb, offset, 2, FALSE);
+ 	offset= offset +2;
+
+	/* Link Layer Service Data Unit (i.e. a layer 3 message
+	 * as defined in 3GPP TS 24.008 or 3GPP TS 44.018)
+	 */
+
+	proto_tree_add_text(ie_tree, tvb,offset,length,"Link Layer Service Data Unit ( L3 Message)");
+	next_tvb = tvb_new_subset(tvb, offset, length, length);
+	call_dissector(gsm_a_dtap_handle, next_tvb, pinfo, top_tree);
+
+	offset = offset + length;
+
+	return offset;
+ }
+
+
+/*
+ * 9.3.16 Physical Context TLV
+ */
+static int
+dissect_rsl_ie_phy_ctx(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+	proto_item *ti;
+	proto_tree *ie_tree;
+	guint length;
+
+	ti = proto_tree_add_text(tree, tvb,offset,0,"Physical Context IE ");
+	ie_tree = proto_item_add_subtree(ti, ett_ie_phy_ctx);
+
+	/* Element identifier */
+	proto_tree_add_item(ie_tree, hf_rsl_ie_id, tvb, offset, 1, FALSE);
+	offset++;
+	/* Length */
+	length = tvb_get_guint8(tvb,offset);
+	proto_item_set_len(ti, length+2);
+	proto_tree_add_item(ie_tree, hf_rsl_ie_length, tvb, offset, 1, FALSE);
+	offset++;
+
+	/*
+	 * Physical Context Information:
+	 *	The Physical Context Information field is not specified. 
+	 *	This information should not be analysed by BSC, but merely
+	 *	forwarded from one TRX/channel to another.
+	 */
+	proto_tree_add_item(ie_tree, hf_rsl_phy_ctx, tvb, offset, length, FALSE);
+	offset = offset + length;
+
+	return offset;
+}
+/*
+ * 9.3.17 Access Delay M TV 2 
+ */
+static int
+dissect_rsl_ie_access_delay(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+	proto_item *ti;
+	proto_tree *ie_tree;
+
+	ti = proto_tree_add_text(tree, tvb,offset,2,"Access Delay IE ");
+	ie_tree = proto_item_add_subtree(ti, ett_ie_access_delay);
+
+	/* Element identifier */
+	proto_tree_add_item(ie_tree, hf_rsl_ie_id, tvb, offset, 1, FALSE);
+	offset++;
+	proto_tree_add_item(ie_tree, hf_rsl_acc_delay, tvb, offset, 1, FALSE);
+	offset++;
+	return offset;
+}
+/*
+ * 9.3.19 Request Reference M TV 4 
+ */
+static int
+dissect_rsl_ie_req_ref(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+	proto_item *ti;
+	proto_tree *ie_tree;
+
+	ti = proto_tree_add_text(tree, tvb,offset,4,"Request Reference IE ");
+	ie_tree = proto_item_add_subtree(ti, ett_ie_req_ref);
+
+	/* Element identifier */
+	proto_tree_add_item(ie_tree, hf_rsl_ie_id, tvb, offset, 1, FALSE);
+	offset++;
+	proto_tree_add_item(ie_tree, hf_rsl_req_ref_ra, tvb, offset, 1, FALSE);
+	offset++;
+	proto_tree_add_item(ie_tree, hf_rsl_req_ref_T1prim, tvb, offset, 1, FALSE);
+	proto_tree_add_item(ie_tree, hf_rsl_req_ref_T3, tvb, offset, 2, FALSE);
+	offset++;
+	proto_tree_add_item(ie_tree, hf_rsl_req_ref_T2, tvb, offset, 1, FALSE);
+	offset++;
+	return offset;
+}
+
+static const value_string rel_mode_vals[] = {
+	{  0x00,	"Normal Release" },
+	{  0x01,	"Local End Release" },
+	{ 0,			NULL }
+};
+
+/*
+ * 9.3.20 Release Mode				9.3.20	M TV 2
+ */
+dissect_rsl_ie_rel_mode(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+	proto_item *ti;
+	proto_tree *ie_tree;
+
+	ti = proto_tree_add_text(tree, tvb,offset,4,"Release Mode IE ");
+	ie_tree = proto_item_add_subtree(ti, ett_ie_req_ref);
+
+	/* Element identifier */
+	proto_tree_add_item(ie_tree, hf_rsl_ie_id, tvb, offset, 1, FALSE);
+	offset++;
+
+	/* 	The M bit is coded as follows:
+	 * 0 normal release
+	 * 1 local end release
+	 */
+	proto_tree_add_item(ie_tree, hf_rsl_rel_mode, tvb, offset, 1, FALSE);
+
+	offset++;
+	return offset;
+}
+
+static const value_string rsl_cause_vals[] = {
+	{  0x00,	"reserved" },
+	{  0x01,	"timer T200 expired (N200+1) times" },
+	{  0x02,	"re-establishment request" },
+	{  0x03,	"unsolicited UA response" },
+	{  0x04,	"unsolicited DM response" },
+	{  0x05,	"unsolicated DM response, multiple frame established state" },
+	{  0x06,	"unsolicited supervisory response" },
+	{  0x07,	"sequence error" },
+	{  0x08,	"U-frame with incorrect parameters" },
+	{  0x09,	"S-frame with incorrect parameters" },
+	{  0x0a,	"I-frame with incorrect use of M bit" },
+	{  0x0b,	"I-frame with incorrect length" },
+	{  0x0c,	"frame not implemented" },
+	{  0x0d,	"SABM command, multiple frame established state" },
+	{  0x0e,	"SABM frame with information not allowed in this state" },
+	{ 0,			NULL }
+};
+
+
+/* 
+ * 9.3.22 RLM Cause				9.3.22	M TLV 2-4	
+ */
+dissect_rsl_ie_rlm_cause(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+	proto_item *ti;
+	proto_tree *ie_tree;
+
+	guint		length;
+
+	ti = proto_tree_add_text(tree, tvb,offset,0,"RLM Cause IE ");
+	ie_tree = proto_item_add_subtree(ti, ett_ie_full_imm_ass_inf);
+
+	/* Element identifier */
+	proto_tree_add_item(ie_tree, hf_rsl_ie_id, tvb, offset, 1, FALSE);
+	offset++;
+	/* Length */
+	length = tvb_get_guint8(tvb,offset);
+	proto_item_set_len(ti, length+2);
+
+	proto_tree_add_item(ie_tree, hf_rsl_ie_length, tvb, offset, 1, FALSE);
+
+	/* The Cause Value is a one octet field if the extension bit is set to 0. 
+	 * If the extension bit is set to 1, the Cause Value is a two octet field.
+	 */
+	proto_tree_add_item(ie_tree, hf_rsl_cause, tvb, offset, 1, FALSE);
+	offset++;
+	offset = offset + length;
+
+	return offset;
+}
+
+/*
+ * 9.3.35 Full Immediate Assign Info TLV 25
+ */
+static int
+dissect_rsl_ie_full_imm_ass_inf(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+	proto_item *ti;
+	proto_tree *ie_tree;
+
+	guint		length;
+	tvbuff_t	*next_tvb;
+
+	ti = proto_tree_add_text(tree, tvb,offset,0,"Full Immediate Assign Info IE ");
+	ie_tree = proto_item_add_subtree(ti, ett_ie_full_imm_ass_inf);
+
+	/* Element identifier */
+	proto_tree_add_item(ie_tree, hf_rsl_ie_id, tvb, offset, 1, FALSE);
+	offset++;
+	/* Length */
+	length = tvb_get_guint8(tvb,offset);
+	proto_item_set_len(ti, length+2);
+
+	proto_tree_add_item(ie_tree, hf_rsl_ie_length, tvb, offset, 1, FALSE);
+	offset++;
+	/*	The Full Immediate Assign Info field (octets 3-25) 
+	 * contains a complete immediate assign message (IMMEDIATE ASSIGNMENT or
+	 * IMMEDIATE ASSIGNMENT EXTENDED or IMMEDIATE ASSIGNMENT REJECT)
+	 * as defined in 3GPP TS 44.018.
+	 */
+	proto_tree_add_text(ie_tree, tvb,offset,length,"Full Immediate Assign Info field");
+	next_tvb = tvb_new_subset(tvb, offset, length, length);
+	call_dissector(gsm_a_ccch_handle, next_tvb, pinfo, top_tree);
+
+	offset = offset + length;
+
+	return offset;
+}
+static int
+dissct_rsl_msg(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+	guint8	msg_type;
+
+	msg_type = tvb_get_guint8(tvb,offset)&0x7f;
+	proto_tree_add_item(tree, hf_rsl_msg_type, tvb, offset, 1, FALSE);
+	offset++;
+
+	if (check_col(pinfo->cinfo, COL_INFO)){
+		col_append_fstr(pinfo->cinfo, COL_INFO, "%s ",val_to_str(msg_type, rsl_msg_type_vals,"unknown %u"));
+	}
+
+
+	switch (msg_type){
+/* Radio Link Layer Management messages */
+	/* 8.3.1 DATA REQUEST */
+	case RSL_MSG_TYPE_DATA_REQ:
+		/* Channel number			9.3.1	M TV 2		*/
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* Link Identifier			9.3.2	M TV 2		*/
+		offset = dissect_rsl_ie_link_id(tvb, pinfo, tree, offset);
+		/* L3 Information			9.3.11	M TLV >=3	*/
+		offset = dissect_rsl_ie_L3_inf(tvb, pinfo, tree, offset);
+		break;
+	/* 8.3.2 DATA INDICATION */
+	case RSL_MSG_TYPE_DATA_IND:
+		/* Channel number			9.3.1	M TV 2		*/
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* Link Identifier			9.3.2	M TV 2		*/
+		offset = dissect_rsl_ie_link_id(tvb, pinfo, tree, offset);
+		/* L3 Information			9.3.11	M TLV >=3	*/
+		offset = dissect_rsl_ie_L3_inf(tvb, pinfo, tree, offset);
+		break;
+	/* 8.3.3 ERROR INDICATION */
+	case RSL_MSG_TYPE_ERROR_IND:
+		/* Channel number			9.3.1	M TV 2		*/
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* Link Identifier			9.3.2	M TV 2		*/
+		offset = dissect_rsl_ie_link_id(tvb, pinfo, tree, offset);
+		/* RLM Cause				9.3.22	M TLV 2-4	*/
+		offset = dissect_rsl_ie_rlm_cause(tvb, pinfo, tree, offset);
+		break;
+	/* 8.3.4 ESTABLISH REQUEST */
+	case RSL_MSG_TYPE_EST_REQ:
+		/* Channel number			9.3.1	M TV 2		*/
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* Link Identifier			9.3.2	M TV 2		*/
+		offset = dissect_rsl_ie_link_id(tvb, pinfo, tree, offset);
+		break;
+	/* 8.3.5 ESTABLISH CONFIRM */
+	case RSL_MSG_TYPE_EST_CONF:
+		/* Channel number			9.3.1	M TV 2		*/
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* Link Identifier			9.3.2	M TV 2		*/
+		offset = dissect_rsl_ie_link_id(tvb, pinfo, tree, offset);
+		break;
+	/* 8.3.6 */
+	case RSL_MSG_EST_IND:
+		/* 	Channel number			9.3.1	M TV 2				 */
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* 	Link Identifier			9.3.2	M TV 2				 */
+		offset = dissect_rsl_ie_link_id(tvb, pinfo, tree, offset);
+		/* 	L3 Information			9.3.11	O (note 1) TLV 3-23	 */
+		if(tvb_length_remaining(tvb,offset) >1)
+			offset = dissect_rsl_ie_L3_inf(tvb, pinfo, tree, offset);
+		break;
+	/* 8.3.7 RELEASE REQUEST */
+	case RSL_MSG_REL_REQ:
+		/* 	Channel number			9.3.1	M TV 2				 */
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* 	Link Identifier			9.3.2	M TV 2				 */
+		offset = dissect_rsl_ie_link_id(tvb, pinfo, tree, offset);
+		/* Release Mode				9.3.20	M TV 2				*/
+		offset = dissect_rsl_ie_rel_mode(tvb, pinfo, tree, offset);
+		break;
+	/* 8.3.8 RELEASE CONFIRM */
+	case RSL_MSG_REL_CONF:
+		/* 	Channel number			9.3.1	M TV 2				 */
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* 	Link Identifier			9.3.2	M TV 2				 */
+		offset = dissect_rsl_ie_link_id(tvb, pinfo, tree, offset);
+		break;
+	/* 8.3.9 RELEASE INDICATION */
+	case RSL_MSG_REL_IND:
+		/* 	Channel number			9.3.1	M TV 2				 */
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* 	Link Identifier			9.3.2	M TV 2				 */
+		offset = dissect_rsl_ie_link_id(tvb, pinfo, tree, offset);
+		break;
+	/* 8.3.10 UNIT DATA REQUEST */
+	case RSL_MSG_UNIT_DATA_REQ:
+		/* 	Channel number			9.3.1	M TV 2				 */
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* 	Link Identifier			9.3.2	M TV 2				 */
+		offset = dissect_rsl_ie_link_id(tvb, pinfo, tree, offset);
+		/* 	L3 Information			9.3.11	O (note 1) TLV 3-23	 */
+		offset = dissect_rsl_ie_L3_inf(tvb, pinfo, tree, offset);
+		break;
+
+/* Common Channel Management/TRX Management messages: */ 
+	/* 8.5.3 */
+	case RSL_MSG_CHANRQD:
+		/* Channel number			9.3.1	M TV 2 */
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* Request Reference		9.3.19	M TV 4 */
+		offset = dissect_rsl_ie_req_ref(tvb, pinfo, tree, offset);
+		/* Access Delay				9.3.17	M TV 2 */
+		offset = dissect_rsl_ie_access_delay(tvb, pinfo, tree, offset);
+		/* Physical Context			9.3.16	O 1) TLV >=2 */
+		if(tvb_length_remaining(tvb,offset) > 0)
+			offset = dissect_rsl_ie_phy_ctx(tvb, pinfo, tree, offset);
+		break;
+	case RSL_MSG_IMM_ASS_CMD:
+		/* Channel number			9.3.1	M TV 2 */
+		offset = dissect_rsl_ie_ch_no(tvb, pinfo, tree, offset);
+		/* Full Imm. Assign Info	9.3.35	M TLV 25 */
+		offset = dissect_rsl_ie_full_imm_ass_inf(tvb, pinfo, tree, offset);
+		break;
+/* Dedicated Channel Management messages: */
+	default:
+		break;
+	}
+
+	return offset;
+
+}
+static void
+dissect_rsl(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+	proto_item *ti;
+	proto_tree *rsl_tree;
+
+
+	int offset = 0;
+
+	if (check_col(pinfo->cinfo, COL_PROTOCOL))
+		col_set_str(pinfo->cinfo, COL_PROTOCOL, "RSL");
+	if (check_col(pinfo->cinfo, COL_INFO))
+		col_clear(pinfo->cinfo, COL_INFO);
+
+	top_tree = tree;
+	/*if (tree) {*/
+		ti = proto_tree_add_item(tree, proto_rsl, tvb, 0, -1, FALSE);
+		rsl_tree = proto_item_add_subtree(ti, ett_rsl);
+
+		/* 9.1 Message discriminator */
+		proto_tree_add_item(rsl_tree, hf_rsl_msg_dsc, tvb, offset, 1, FALSE);
+		proto_tree_add_item(rsl_tree, hf_rsl_T_bit, tvb, offset, 1, FALSE);
+		offset++;
+		offset = dissct_rsl_msg(tvb, pinfo, rsl_tree, offset );
+		
+	/*}*/
+
+}
+
+void
+proto_reg_handoff_rsl(void)
+{
+	dissector_handle_t rsl_handle;
+
+	rsl_handle = create_dissector_handle(dissect_rsl, proto_rsl);
+	dissector_add("lapd.gsm.sapi", LAPD_GSM_SAPI_RA_SIG_PROC, rsl_handle);
+
+	gsm_a_ccch_handle = find_dissector("gsm_a_ccch");
+	gsm_a_dtap_handle = find_dissector("gsm_a_dtap");
+}
+
+/* Register the protocol with Wireshark */
+void proto_register_rsl(void)
+{
+
+	/* Setup list of header fields */
+	static hf_register_info hf[] = {
+		{ &hf_rsl_msg_dsc,
+			{ "Message discriminator",           "rsl.msg_dsc",
+			FT_UINT8, BASE_DEC, VALS(rsl_msg_disc_vals), 0xfe,          
+			"Message discriminator", HFILL }
+		},
+		{ &hf_rsl_T_bit,
+			{ "T bit",           "rsl.T_bit",
+			FT_BOOLEAN, 8, TFS(&rsl_t_bit_vals), 0x01,          
+			"T bit", HFILL }
+		},
+		{ &hf_rsl_msg_type,
+			{ "Message type",           "rsl.msg_type",
+			FT_UINT8, BASE_HEX_DEC, VALS(rsl_msg_type_vals), 0x7f,          
+			"Message type", HFILL }
+		},
+		{ &hf_rsl_ie_id,
+			{ "Element identifier",           "rsl.ie_id",
+			FT_UINT8, BASE_HEX_DEC, VALS(rsl_ie_type_vals), 0x0,          
+			"Element identifier", HFILL }
+		},
+		{ &hf_rsl_ie_length,
+			{ "Length",           "rsl.ie_length",
+			FT_UINT16, BASE_DEC, NULL, 0x0,          
+			"Length", HFILL }
+		},
+		{ &hf_rsl_ch_no_Cbits,
+			{ "C-bits",           "rsl.ch_no_Cbits",
+			FT_UINT8, BASE_DEC, VALS(rsl_ch_no_Cbits_vals), 0xf8,          
+			"C-bits", HFILL }
+		},
+		{ &hf_rsl_ch_no_TN,
+			{ "Time slot number (TN)",  "rsl.ch_no_TN",
+			FT_UINT8, BASE_DEC, NULL, 0x03,          
+			"Time slot number (TN)", HFILL }
+		},
+		{ &hf_rsl_req_ref_ra,
+			{ "Random Access Information (RA)", "rsl.req_ref_ra",
+			FT_UINT8, BASE_DEC, NULL, 0x0,          
+			"Random Access Information (RA)", HFILL }
+		},
+		{ &hf_rsl_req_ref_T1prim,
+			{ "T1'",           "rsl.req_ref_T1prim",
+			FT_UINT8, BASE_DEC, NULL, 0xf8,          
+			"T1'", HFILL }
+		},
+		{ &hf_rsl_req_ref_T3,
+			{ "T3",           "rsl.req_ref_T3",
+			FT_UINT16, BASE_DEC, NULL, 0x07e0,          
+			"T3", HFILL }
+		},
+		{ &hf_rsl_req_ref_T2,
+			{ "T2",           "rsl.req_ref_T2",
+			FT_UINT8, BASE_DEC, NULL, 0x1f,          
+			"T2", HFILL }
+		},
+		{ &hf_rsl_acc_delay,
+			{ "Access Delay",           "rsl.acc_del",
+			FT_UINT8, BASE_DEC, NULL, 0x0,          
+			"Access Delay", HFILL }
+		},
+		{ &hf_rsl_phy_ctx,
+			{ "Physical Context",           "rsl.phy_ctx",
+			FT_BYTES, BASE_NONE, NULL, 0x0,          
+			"Physical Context", HFILL }
+		},
+		{ &hf_rsl_na,
+			{ "Not applicable (NA)",           "rsl.na",
+			FT_BOOLEAN, 8, TFS(&rsl_na_vals), 0x20,          
+			"Not applicable (NA)", HFILL }
+		},
+		{ &hf_rsl_ch_type,
+			{ "channel type",           "rsl.ch_type",
+			FT_UINT8, BASE_DEC, VALS(rsl_ch_type_vals), 0xc0,          
+			"channel type", HFILL }
+		},
+		{ &hf_rsl_prio,
+			{ "Priority",           "rsl.prio",
+			FT_UINT8, BASE_DEC, VALS(rsl_prio_vals), 0x18,          
+			"Priority", HFILL }
+		},
+		{ &hf_rsl_sapi,
+			{ "SAPI",           "rsl.sapi",
+			FT_UINT8, BASE_DEC, NULL, 0x07,          
+			"SAPI", HFILL }
+		},
+		{ &hf_rsl_cause,
+			{ "Cause",           "rsl.cause",
+			FT_UINT8, BASE_DEC, VALS(rsl_cause_vals), 0x7f,          
+			"Cause", HFILL }
+		},
+		{ &hf_rsl_rel_mode,
+			{ "Release Mode",           "rsl.rel_mode",
+			FT_UINT8, BASE_DEC, VALS(rel_mode_vals), 0x01,          
+			"Relese Mode", HFILL }
+		},
+
+	};
+	static gint *ett[] = {
+		&ett_rsl,
+		&ett_ie_ch_no,
+		&ett_ie_phy_ctx,
+		&ett_ie_access_delay,
+		&ett_ie_req_ref,
+		&ett_ie_full_imm_ass_inf,
+	};
+
+	/* Register the protocol name and description */
+	proto_rsl = proto_register_protocol("Radio Signalling Link (RSL)",
+	                                    "RSL", "rsl");
+
+	proto_register_field_array(proto_rsl, hf, array_length(hf));
+	proto_register_subtree_array(ett, array_length(ett));
+
+
+}