/* packet-gsm_a_rp.c
 * Routines for GSM A Interface RP dissection - SMS GSM layer 3
 *
 * Copyright 2003, Michael Lum <mlum [AT] telostech.com>
 * In association with Telos Technology Inc.
 *
 * Title		3GPP			Other
 *
 *   Reference [5]
 *   Point-to-Point (PP) Short Message Service (SMS)
 *   support on mobile radio interface
 *   (3GPP TS 24.011 version 4.1.1 Release 4)
 *
 * $Id$
 *
 * 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.
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <glib.h>

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

#include "packet-sccp.h"
#include "packet-gsm_a_common.h"

/* PROTOTYPES/FORWARDS */

static const value_string gsm_rp_msg_strings[] = {
	{ 0x00,	"RP-DATA (MS to Network)" },
	{ 0x01,	"RP-DATA (Network to MS)" },
	{ 0x02,	"RP-ACK (MS to Network)" },
	{ 0x03,	"RP-ACK (Network to MS)" },
	{ 0x04,	"RP-ERROR (MS to Network)" },
	{ 0x05,	"RP-ERROR (Network to MS)" },
	{ 0x06,	"RP-SMMA (MS to Network)" },
	{ 0, NULL }
};

const value_string gsm_rp_elem_strings[] = {
	/* Short Message Service RP Information Elements [5] 8.2 */
	{ 0x00,	"RP-Message Reference" },
	{ 0x00,	"RP-Origination Address" },
	{ 0x00,	"RP-Destination Address" },
	{ 0x00,	"RP-User Data" },
	{ 0x00,	"RP-Cause" },
	{ 0, NULL }
};

/* Initialize the protocol and registered fields */
static int proto_a_rp = -1;

static int hf_gsm_a_rp_msg_type = -1;
int hf_gsm_a_rp_elem_id = -1;

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

static char a_bigbuf[1024];

static dissector_table_t sms_dissector_table;	/* SMS TPDU */

static proto_tree *g_tree;

typedef enum
{
	/* Short Message Service Information Elements [5] 8.2 */
	DE_RP_MESSAGE_REF,				/* RP-Message Reference */
	DE_RP_ORIG_ADDR,				/* RP-Origination Address */
	DE_RP_DEST_ADDR,				/* RP-Destination Address */
	DE_RP_USER_DATA,				/* RP-User Data */
	DE_RP_CAUSE,					/* RP-Cause */
	DE_RP_NONE							/* NONE */
}
rp_elem_idx_t;

#define	NUM_GSM_RP_ELEM (sizeof(gsm_rp_elem_strings)/sizeof(value_string))
gint ett_gsm_rp_elem[NUM_GSM_RP_ELEM];

/*
 * [5] 8.2.3
 */
static guint16
de_rp_message_ref(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
{
	guint8	oct;
	guint32	curr_offset;

	curr_offset = offset;

	oct = tvb_get_guint8(tvb, curr_offset);

	proto_tree_add_text(tree,
		tvb, curr_offset, 1,
		"RP-Message Reference: 0x%02x (%u)",
		oct,
		oct);

	curr_offset++;

	/* no length check possible */

	return(curr_offset - offset);
}

/*
 * [5] 8.2.5.1
 */
static guint16
de_rp_orig_addr(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len, gchar *add_string, int string_len)
{
	return(de_cld_party_bcd_num(tvb, tree, pinfo, offset, len, add_string, string_len));
}

/*
 * [5] 8.2.5.2
 */
static guint16
de_rp_dest_addr(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len, gchar *add_string, int string_len)
{
	return(de_cld_party_bcd_num(tvb, tree, pinfo, offset, len, add_string, string_len));
}

/*
 * [5] 8.2.5.3
 */
static guint16
de_rp_user_data(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len, gchar *add_string _U_, int string_len _U_)
{
	guint32	curr_offset;
	tvbuff_t	*tpdu_tvb;

	curr_offset = offset;

	proto_tree_add_text(tree, tvb, curr_offset, len,
		"TPDU (not displayed)");

	/*
	 * dissect the embedded TPDU message
	 */
	tpdu_tvb = tvb_new_subset(tvb, curr_offset, len, len);

	dissector_try_uint(sms_dissector_table, 0, tpdu_tvb, pinfo, g_tree);

	curr_offset += len;

	EXTRANEOUS_DATA_CHECK(len, curr_offset - offset);

	return(curr_offset - offset);
}

/*
 * [5] 8.2.5.4
 */
static guint16
de_rp_cause(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len, gchar *add_string, int string_len)
{
	guint8	oct;
	guint32	curr_offset;
	const gchar *str;

	curr_offset = offset;

	oct = tvb_get_guint8(tvb, curr_offset);

	other_decode_bitfield_value(a_bigbuf, oct, 0x80, 8);
	proto_tree_add_text(tree,
		tvb, curr_offset, 1,
		"%s :  Extension: %s",
		a_bigbuf,
		(oct & 0x80) ? "extended" : "not extended");

	switch (oct & 0x7f)
	{
	case 1: str = "Unassigned (unallocated) number"; break;
	case 8: str = "Operator determined barring"; break;
	case 10: str = "Call barred"; break;
	case 11: str = "Reserved"; break;
	case 21: str = "Short message transfer rejected"; break;
	case 22: str = "Memory capacity exceeded"; break;
	case 27: str = "Destination out of order"; break;
	case 28: str = "Unidentified subscriber"; break;
	case 29: str = "Facility rejected"; break;
	case 30: str = "Unknown subscriber"; break;
	case 38: str = "Network out of order"; break;
	case 41: str = "Temporary failure"; break;
	case 42: str = "Congestion"; break;
	case 47: str = "Resources unavailable, unspecified"; break;
	case 50: str = "Requested facility not subscribed"; break;
	case 69: str = "Requested facility not implemented"; break;
	case 81: str = "Invalid short message transfer reference value"; break;
	case 95: str = "Semantically incorrect message"; break;
	case 96: str = "Invalid mandatory information"; break;
	case 97: str = "Message type non-existent or not implemented"; break;
	case 98: str = "Message not compatible with short message protocol state"; break;
	case 99: str = "Information element non-existent or not implemented"; break;
	case 111: str = "Protocol error, unspecified"; break;
	case 127: str = "Interworking, unspecified"; break;
	default:
		str = "Reserved";
		break;
	}

	other_decode_bitfield_value(a_bigbuf, oct, 0x7f, 8);
	proto_tree_add_text(tree,
		tvb, curr_offset, 1,
		"%s :  Cause: (%u) %s",
		a_bigbuf,
		oct & 0x7f,
		str);

	curr_offset++;

	if (add_string)
		g_snprintf(add_string, string_len, " - (%u) %s", oct & 0x7f, str);

	NO_MORE_DATA_CHECK(len);

	proto_tree_add_text(tree,
		tvb, curr_offset, len - (curr_offset - offset),
		"Diagnostic field");

	curr_offset += len - (curr_offset - offset);

	EXTRANEOUS_DATA_CHECK(len, curr_offset - offset);

	return(curr_offset - offset);
}

guint16 (*rp_elem_fcn[])(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len, gchar *add_string, int string_len) = {
	/* Short Message Service Information Elements [5] 8.2 */
	de_rp_message_ref,	/* RP-Message Reference */
	de_rp_orig_addr,	/* RP-Origination Address */
	de_rp_dest_addr,	/* RP-Destination Address */
	de_rp_user_data,	/* RP-User Data */
	de_rp_cause,	/* RP-Cause */
	NULL,	/* NONE */
};

/* MESSAGE FUNCTIONS */

/*
 * [5] 7.3.1.1
 */
void
rp_data_n_ms(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len)
{
	guint32	curr_offset;
	guint32	consumed;
	guint	curr_len;

	curr_offset = offset;
	curr_len = len;

	pinfo->p2p_dir = P2P_DIR_SENT;

	ELEM_MAND_V(GSM_A_PDU_TYPE_RP, DE_RP_MESSAGE_REF, NULL);

	ELEM_MAND_LV(GSM_A_PDU_TYPE_RP, DE_RP_ORIG_ADDR, NULL);

	ELEM_MAND_LV(GSM_A_PDU_TYPE_RP, DE_RP_DEST_ADDR, NULL);

	ELEM_MAND_LV(GSM_A_PDU_TYPE_RP, DE_RP_USER_DATA, NULL);

	EXTRANEOUS_DATA_CHECK(curr_len, 0);
}

/*
 * [5] 7.3.1.2
 */
static void
rp_data_ms_n(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len)
{
	guint32	curr_offset;
	guint32	consumed;
	guint	curr_len;

	curr_offset = offset;
	curr_len = len;

	pinfo->p2p_dir = P2P_DIR_RECV;

	ELEM_MAND_V(GSM_A_PDU_TYPE_RP, DE_RP_MESSAGE_REF, NULL);

	ELEM_MAND_LV(GSM_A_PDU_TYPE_RP, DE_RP_ORIG_ADDR, NULL);

	ELEM_MAND_LV(GSM_A_PDU_TYPE_RP, DE_RP_DEST_ADDR, NULL);

	ELEM_MAND_LV(GSM_A_PDU_TYPE_RP, DE_RP_USER_DATA, NULL);

	EXTRANEOUS_DATA_CHECK(curr_len, 0);
}

/*
 * [5] 7.3.2
 */
static void
rp_smma(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
{
	guint32	curr_offset;
	guint32	consumed;
	guint	curr_len;

	curr_offset = offset;
	curr_len = len;

	ELEM_MAND_V(GSM_A_PDU_TYPE_RP, DE_RP_MESSAGE_REF, NULL);

	EXTRANEOUS_DATA_CHECK(curr_len, 0);
}

/*
 * [5] 7.3.3
 */
static void
rp_ack_n_ms(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len)
{
	guint32	curr_offset;
	guint32	consumed;
	guint	curr_len;

	curr_offset = offset;
	curr_len = len;

	pinfo->p2p_dir = P2P_DIR_SENT;

	ELEM_MAND_V(GSM_A_PDU_TYPE_RP, DE_RP_MESSAGE_REF, NULL);

	ELEM_OPT_TLV(0x41, GSM_A_PDU_TYPE_RP, DE_RP_USER_DATA, NULL);

	EXTRANEOUS_DATA_CHECK(curr_len, 0);
}

/*
 * [5] 7.3.3
 */
static void
rp_ack_ms_n(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len)
{
	guint32	curr_offset;
	guint32	consumed;
	guint	curr_len;

	curr_offset = offset;
	curr_len = len;

	pinfo->p2p_dir = P2P_DIR_RECV;

	ELEM_MAND_V(GSM_A_PDU_TYPE_RP, DE_RP_MESSAGE_REF, NULL);

	ELEM_OPT_TLV(0x41, GSM_A_PDU_TYPE_RP, DE_RP_USER_DATA, NULL);

	EXTRANEOUS_DATA_CHECK(curr_len, 0);
}

/*
 * [5] 7.3.4
 */
static void
rp_error_n_ms(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len)
{
	guint32	curr_offset;
	guint32	consumed;
	guint	curr_len;

	curr_offset = offset;
	curr_len = len;

	pinfo->p2p_dir = P2P_DIR_SENT;

	ELEM_MAND_V(GSM_A_PDU_TYPE_RP, DE_RP_MESSAGE_REF, NULL);

	ELEM_MAND_LV(GSM_A_PDU_TYPE_RP, DE_RP_CAUSE, NULL);

	ELEM_OPT_TLV(0x41, GSM_A_PDU_TYPE_RP, DE_RP_USER_DATA, NULL);

	EXTRANEOUS_DATA_CHECK(curr_len, 0);
}

/*
 * [5] 7.3.4
 */
static void
rp_error_ms_n(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len)
{
	guint32	curr_offset;
	guint32	consumed;
	guint	curr_len;

	curr_offset = offset;
	curr_len = len;

	pinfo->p2p_dir = P2P_DIR_RECV;

	ELEM_MAND_V(GSM_A_PDU_TYPE_RP, DE_RP_MESSAGE_REF, NULL);

	ELEM_MAND_LV(GSM_A_PDU_TYPE_RP, DE_RP_CAUSE, NULL);

	ELEM_OPT_TLV(0x41, GSM_A_PDU_TYPE_RP, DE_RP_USER_DATA, NULL);

	EXTRANEOUS_DATA_CHECK(curr_len, 0);
}

#define	NUM_GSM_RP_MSG (sizeof(gsm_rp_msg_strings)/sizeof(value_string))
static gint ett_gsm_rp_msg[NUM_GSM_RP_MSG];
static void (*rp_msg_fcn[])(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len) = {
	rp_data_ms_n,	/* RP-DATA (MS to Network) */
	rp_data_n_ms,	/* RP-DATA (Network to MS) */
	rp_ack_ms_n,	/* RP-ACK (MS to Network) */
	rp_ack_n_ms,	/* RP-ACK (Network to MS) */
	rp_error_ms_n,	/* RP-ERROR (MS to Network) */
	rp_error_n_ms,	/* RP-ERROR (Network to MS) */
	rp_smma,	/* RP-SMMA (MS to Network) */
	NULL,	/* NONE */
};

/* GENERIC DISSECTOR FUNCTIONS */

static void
dissect_rp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
	guint8	oct;
	guint32	offset, saved_offset;
	guint32	len;
	gint	idx;
	proto_item	*rp_item = NULL;
	proto_tree	*rp_tree = NULL;
	const gchar	*str;

	col_append_str(pinfo->cinfo, COL_INFO, "(RP) ");

	/*
	 * In the interest of speed, if "tree" is NULL, don't do any work
	 * not necessary to generate protocol tree items.
	 */
	if (!tree)
	{
		return;
	}

	offset = 0;
	saved_offset = offset;

	g_tree = tree;

	len = tvb_length(tvb);

	/*
	 * add RP message name
	 */
	oct = tvb_get_guint8(tvb, offset++);

	str = match_strval_idx((guint32) oct, gsm_rp_msg_strings, &idx);

	/*
	 * create the protocol tree
	 */
	if (str == NULL)
	{
		rp_item =
			proto_tree_add_protocol_format(tree, proto_a_rp, tvb, 0, len,
				"GSM A-I/F RP - Unknown RP Message Type (0x%02x)",
				oct);

		rp_tree = proto_item_add_subtree(rp_item, ett_rp_msg);
	}
	else
	{
		rp_item =
			proto_tree_add_protocol_format(tree, proto_a_rp, tvb, 0, -1,
				"GSM A-I/F RP - %s",
				str);

		rp_tree = proto_item_add_subtree(rp_item, ett_gsm_rp_msg[idx]);

		col_append_fstr(pinfo->cinfo, COL_INFO, "%s ", str);
	}

	/*
	 * add RP message name
	 */
	proto_tree_add_uint_format(rp_tree, hf_gsm_a_rp_msg_type,
		tvb, saved_offset, 1, oct, "Message Type %s", str ? str : "(Unknown)");

	if (str == NULL) return;

	if (offset >=len) return;

	/*
	 * decode elements
	 */
	if (rp_msg_fcn[idx] == NULL)
	{
		proto_tree_add_text(rp_tree,
			tvb, offset, len - offset,
		"Message Elements");
	}
	else
	{
		(*rp_msg_fcn[idx])(tvb, rp_tree, pinfo, offset, len - offset);
	}
}

/* Register the protocol with Wireshark */
void
proto_register_gsm_a_rp(void)
{
	guint		i;
	guint		last_offset;

	/* Setup list of header fields */

	static hf_register_info hf[] =
	{
	{ &hf_gsm_a_rp_msg_type,
		{ "RP Message Type",	"gsm_a_rp.msg_type",
		FT_UINT8, BASE_HEX, VALS(gsm_rp_msg_strings), 0x0,
		NULL, HFILL }
	},
	{ &hf_gsm_a_rp_elem_id,
		{ "Element ID",	"gsm_a_rp.elem_id",
		FT_UINT8, BASE_HEX, NULL, 0,
		NULL, HFILL }
	},
	};

	/* Setup protocol subtree array */
#define	NUM_INDIVIDUAL_ELEMS	1
	gint *ett[NUM_INDIVIDUAL_ELEMS +
		  NUM_GSM_RP_MSG +
		  NUM_GSM_RP_ELEM];
        
	ett[0] = &ett_rp_msg;

	last_offset = NUM_INDIVIDUAL_ELEMS;

	for (i=0; i < NUM_GSM_RP_MSG; i++, last_offset++)
	{
		ett_gsm_rp_msg[i] = -1;
		ett[last_offset] = &ett_gsm_rp_msg[i];
	}

	for (i=0; i < NUM_GSM_RP_ELEM; i++, last_offset++)
	{
		ett_gsm_rp_elem[i] = -1;
		ett[last_offset] = &ett_gsm_rp_elem[i];
	}

	/* Register the protocol name and description */

	proto_a_rp =
		proto_register_protocol("GSM A-I/F RP", "GSM RP", "gsm_a_rp");

	proto_register_field_array(proto_a_rp, hf, array_length(hf));

	sms_dissector_table =
		register_dissector_table("gsm_a.sms_tpdu", "GSM SMS TPDU",
		FT_UINT8, BASE_DEC);

	proto_register_subtree_array(ett, array_length(ett));

	register_dissector("gsm_a_rp", dissect_rp, proto_a_rp);
}

void
proto_reg_handoff_gsm_a_rp(void)
{
    dissector_handle_t	gsm_a_rp_handle;

	gsm_a_rp_handle = create_dissector_handle(dissect_rp, proto_a_rp);
	/* Dissect messages embedded in SIP */
	dissector_add_string("media_type","application/vnd.3gpp.sms", gsm_a_rp_handle);

}