/* packet-manolito.c
 * Routines for Blubster/Piolet Manolito Protocol dissection
 * Copyright 2003-2004, Jeff Connelly <shellreef+mp2p@gmail.com>
 *
 * Official home page: http://openlito.sourceforge.net/
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "config.h"

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

void proto_register_manolito(void);
void proto_reg_handoff_manolito(void);

static dissector_handle_t manolito_handle;

#define MANOLITO_PORT   41170 /* Not IANA registered */

static int proto_manolito;

static int hf_manolito_checksum;
static int hf_manolito_seqno;
static int hf_manolito_src;
static int hf_manolito_dest;
static int hf_manolito_options_short;
static int hf_manolito_options;
static int hf_manolito_string;
static int hf_manolito_integer;

static int ett_manolito;

static expert_field ei_manolito_type;

#define MANOLITO_STRING  1
#define MANOLITO_INTEGER 0

static const value_string field_longname[] = {
	{ 0x4144, "???" },
	{ 0x4252, "Bit Rate" },
	{ 0x434b, "Checksum" },
	{ 0x434e, "Client Name" },
	{ 0x4356, "Client Version" },
	{ 0x4643, "Frequency" },
	{ 0x464c, "File Length" },
	{ 0x464e, "Filename" },
	{ 0x484e, "???" },
	{ 0x4944, "Identification" },
	{ 0x4d45, "Message" },
	{ 0x4e43, "Num. Connections" },
	{ 0x4e49, "Network ID" },
	{ 0x4e4e, "Nickname" },
	{ 0x5054, "Port" },
	{ 0x5346, "Shared Files" },
	{ 0x534b, "Shared Kilobytes" },
	{ 0x534c, "Song Length (s)" },
	{ 0x5354, "???" },
	{ 0x564c, "Velocity" },
	{ 0, NULL }
};
static value_string_ext field_longname_ext = VALUE_STRING_EXT_INIT(field_longname);


static int
dissect_manolito(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* dissector_data _U_)
{
	int offset = 0;
	proto_item *ti;
	proto_tree *manolito_tree;
	char *packet_type = NULL;

	col_set_str(pinfo->cinfo, COL_PROTOCOL, "MANOLITO");

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

	manolito_tree = proto_item_add_subtree(ti, ett_manolito);

	/* MANOLITO packet header (network byte order) */
	proto_tree_add_checksum(manolito_tree, tvb, offset, hf_manolito_checksum,
	    -1, NULL, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
	offset += 4;
	proto_tree_add_item(manolito_tree,
	    hf_manolito_seqno, tvb, offset, 4, ENC_BIG_ENDIAN);
	offset += 4;
	proto_tree_add_item(manolito_tree,
	    hf_manolito_src, tvb, offset, 4, ENC_BIG_ENDIAN);
	offset += 4;
	proto_tree_add_item(manolito_tree,
	    hf_manolito_dest, tvb, offset, 4, ENC_BIG_ENDIAN);
	offset += 4;

	if (tvb_reported_length_remaining(tvb, offset) == 3) {
		proto_tree_add_item(manolito_tree,
		    hf_manolito_options_short, tvb, offset, 3, ENC_BIG_ENDIAN);
		offset += 3;
		col_set_str(pinfo->cinfo, COL_INFO, "Ping (truncated)");
		return offset;
	}

	proto_tree_add_item(manolito_tree,
			hf_manolito_options, tvb, 16, 4, ENC_BIG_ENDIAN);
	offset += 4;

	if (tvb_reported_length_remaining(tvb, offset) == 0) {
		col_set_str(pinfo->cinfo, COL_INFO, "Ping");
		return offset;
	}

	/* fields format: 2-byte name, optional NULL, 1-byte lenlen, */
	/* that many bytes(len or data), for NI,CN,VL is len, more */
	/* (that many bytes) data follows; else is raw data. */
	do
	{
		uint16_t    field_name;        /* 16-bit field name */
		uint8_t     dtype;             /* data-type */
		uint8_t     length;            /* length */
		int         start;             /* field starting location */
		uint8_t    *field_name_str;

		start = offset;

		/* 2-byte field name */
		field_name = tvb_get_ntohs(tvb, offset);
		field_name_str = tvb_get_string_enc(pinfo->pool, tvb, offset, 2, ENC_ASCII);
		if (!packet_type) {
			/* Identify the packet based on existing fields */
			/* Maybe using the options fields is a better idea...*/
			if (field_name == 0x434b)    /* CK */
				packet_type = "Search Hit";
			if (field_name == 0x4e43)    /* NC */
				packet_type = "User Information";
			if (field_name == 0x464e)    /* FN - if only field */
				packet_type = "Search Query";
			if (field_name == 0x4944)    /* ID ?? search by CK? */
				packet_type = "Search Query (by hash)";
			if (field_name == 0x5054)    /* PT */
				packet_type = "Download Request";
			if (field_name == 0x4d45)    /* ME */
				packet_type = "Chat";
		}
		offset += 2;

		/* 1-byte data type */
		dtype = tvb_get_uint8(tvb, offset);
		offset++;
		length = tvb_get_uint8(tvb, offset);
		offset++;

		if (dtype == MANOLITO_STRING) {
			uint8_t *str;

			str = tvb_get_string_enc(pinfo->pool, tvb, offset, length, ENC_ASCII);
			proto_tree_add_string_format(manolito_tree, hf_manolito_string, tvb, start,
					4+length, str, "%s (%s): %s",
					field_name_str,
					val_to_str_ext_const(field_name, &field_longname_ext, "unknown"),
					str);
			offset += length;
		}
		else if (dtype == MANOLITO_INTEGER) {
			bool len_ok = true;
			uint64_t n = 0;

			/* integers can be up to 5 bytes */
			switch(length)
			{
				case 5:
					n = tvb_get_ntoh40(tvb, offset);
					break;
				case 4:
					n = tvb_get_ntohl(tvb, offset);
					break;
				case 3:
					n = tvb_get_ntoh24(tvb, offset);
					break;
				case 2:
					n = tvb_get_ntohs(tvb, offset);
					break;
				case 1:
					n = tvb_get_uint8(tvb, offset);
					break;

				default:
					len_ok = false;
			}

			if (len_ok) {
				proto_tree_add_uint64_format(manolito_tree, hf_manolito_integer, tvb, start,
						4+length, n, "%s (%s): %" PRIu64,
						field_name_str,
						val_to_str_ext_const(field_name, &field_longname_ext, "unknown"),
						n);
			}
			else {
				/* XXX - expert info */
			}
			offset += length;
		}
		else {
			proto_tree_add_expert_format(manolito_tree, pinfo, &ei_manolito_type,
					tvb, start, offset - start, "Unknown type %d", dtype);
		}

	} while(tvb_reported_length_remaining(tvb, offset));

	if (packet_type)
		col_set_str(pinfo->cinfo, COL_INFO, packet_type);

	return offset;
}


void
proto_register_manolito(void)
{
	static hf_register_info hf[] = {
		{ &hf_manolito_checksum,
		  { "Checksum", "manolito.checksum",
		    FT_UINT32, BASE_HEX, NULL, 0,
		    "Checksum used for verifying integrity", HFILL }
		},
		{ &hf_manolito_seqno,
		  { "Sequence Number", "manolito.seqno",
		    FT_UINT32, BASE_HEX, NULL, 0,
		    "Incremental sequence number", HFILL }
		},
		{ &hf_manolito_src,
		  { "Forwarded IP Address", "manolito.src",
		    FT_IPv4, BASE_NONE, NULL, 0,
		    "Host packet was forwarded from (or 0)", HFILL }
		},
		{ &hf_manolito_dest,
		  { "Destination IP Address", "manolito.dest",
		    FT_IPv4, BASE_NONE, NULL, 0,
		    "Destination IPv4 address", HFILL }
		},
		{ &hf_manolito_options_short,
		  { "Options", "manolito.options",
		    FT_UINT24, BASE_HEX, NULL, 0,
		    "Packet-dependent data", HFILL }
		},
		{ &hf_manolito_options,
		  { "Options", "manolito.options",
		    FT_UINT32, BASE_HEX, NULL, 0,
		    "Packet-dependent data", HFILL }
		},
		{ &hf_manolito_string,
		  { "String field", "manolito.string",
		    FT_STRING, BASE_NONE, NULL, 0,
		    NULL, HFILL }
		},
		{ &hf_manolito_integer,
		  { "Integer field", "manolito.integer",
		    FT_UINT40, BASE_DEC, NULL, 0,
		    NULL, HFILL }
		},
	};

	static int *ett[] = {
		&ett_manolito,
	};

	static ei_register_info ei[] = {
		{ &ei_manolito_type, { "manolito.type.unknown", PI_PROTOCOL, PI_WARN, "Unknown type", EXPFILL }},
	};

	expert_module_t* expert_manolito;

	proto_manolito = proto_register_protocol("Blubster/Piolet MANOLITO Protocol", "Manolito", "manolito");

	proto_register_field_array(proto_manolito, hf, array_length(hf));
	proto_register_subtree_array(ett, array_length(ett));
	expert_manolito = expert_register_protocol(proto_manolito);
	expert_register_field_array(expert_manolito, ei, array_length(ei));

	manolito_handle = register_dissector("manolito", dissect_manolito, proto_manolito);
}


void
proto_reg_handoff_manolito(void)
{
	dissector_add_uint_with_preference("udp.port", MANOLITO_PORT, manolito_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:
 */