/* packet-nntp.c
 * Routines for nntp packet dissection
 * Copyright 1999, Richard Sharpe <rsharpe@ns.aus.com>
 *
 * 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>

void proto_register_nntp(void);
void proto_reg_handoff_nntp(void);

static int proto_nntp = -1;
static int hf_nntp_response = -1;
static int hf_nntp_request = -1;

static gint ett_nntp = -1;

#define TCP_PORT_NNTP			119

static int
dissect_nntp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
	const gchar     *type;
	proto_tree	*nntp_tree;
	proto_item	*ti;
	gint		offset = 0;
	gint		next_offset;
	int		linelen;

	if (pinfo->match_uint == pinfo->destport)
		type = "Request";
	else
		type = "Response";

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

	/*
	 * Put the first line from the buffer into the summary
	 * (but leave out the line terminator).
	 *
	 * Note that "tvb_find_line_end()" will return a value that
	 * is not longer than what's in the buffer, so the
	 * "tvb_get_ptr()" call won't throw an exception.
	 */
	linelen = tvb_find_line_end(tvb, offset, -1, &next_offset, FALSE);
	col_add_fstr(pinfo->cinfo, COL_INFO, "%s: %s", type,
		    tvb_format_text(pinfo->pool, tvb, offset, linelen));

	if (tree) {
		ti = proto_tree_add_item(tree, proto_nntp, tvb, offset, -1,
		    ENC_NA);
		nntp_tree = proto_item_add_subtree(ti, ett_nntp);

		if (pinfo->match_uint == pinfo->destport) {
			ti = proto_tree_add_boolean(nntp_tree,
			    hf_nntp_request, tvb, 0, 0, TRUE);
		} else {
			ti = proto_tree_add_boolean(nntp_tree,
			    hf_nntp_response, tvb, 0, 0, TRUE);
		}
		proto_item_set_hidden(ti);

		/*
		 * Show the request or response as text, a line at a time.
		 * XXX - for requests, we could display the stuff after the
		 * first line, if any, based on what the request was, and
		 * for responses, we could display it based on what the
		 * matching request was, although the latter requires us to
		 * know what the matching request was....
		 */
		while (tvb_offset_exists(tvb, offset)) {
			/*
			 * Find the end of the line.
			 */
			tvb_find_line_end(tvb, offset, -1, &next_offset,
			    FALSE);

			/*
			 * Put this line.
			 */
			proto_tree_add_format_text(nntp_tree, tvb, offset, next_offset - offset);
			offset = next_offset;
		}
	}
	return tvb_captured_length(tvb);
}

void
proto_register_nntp(void)
{
	static hf_register_info hf[] = {
	    { &hf_nntp_response,
	      { "Response",           "nntp.response",
		FT_BOOLEAN, BASE_NONE, NULL, 0x0,
	      	"TRUE if NNTP response", HFILL }},

	    { &hf_nntp_request,
	      { "Request",            "nntp.request",
		FT_BOOLEAN, BASE_NONE, NULL, 0x0,
	      	"TRUE if NNTP request", HFILL }}
	};
	static gint *ett[] = {
		&ett_nntp,
	};

	proto_nntp = proto_register_protocol("Network News Transfer Protocol",
	    "NNTP", "nntp");
	proto_register_field_array(proto_nntp, hf, array_length(hf));
	proto_register_subtree_array(ett, array_length(ett));
}

void
proto_reg_handoff_nntp(void)
{
	dissector_handle_t nntp_handle;

	nntp_handle = create_dissector_handle(dissect_nntp, proto_nntp);
	dissector_add_uint_with_preference("tcp.port", TCP_PORT_NNTP, nntp_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:
 */