/*
 * ssh.c
 *
 * Copyright (C) 2009-2011 by ipoque GmbH
 * Copyright (C) 2011-15 - ntop.org
 *
 * This file is part of nDPI, an open source deep packet inspection
 * library based on the OpenDPI and PACE technology by ipoque GmbH
 *
 * nDPI is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * nDPI 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with nDPI.  If not, see <http://www.gnu.org/licenses/>.
 * 
 */


#include "ndpi_protocols.h"
#ifdef NDPI_PROTOCOL_SSH

static void ndpi_int_ssh_add_connection(struct ndpi_detection_module_struct
										  *ndpi_struct, struct ndpi_flow_struct *flow)
{
	ndpi_int_add_connection(ndpi_struct, flow, NDPI_PROTOCOL_SSH, NDPI_REAL_PROTOCOL);
}

void ndpi_search_ssh_tcp(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)
{
	struct ndpi_packet_struct *packet = &flow->packet;
	
//      struct ndpi_id_struct         *src=ndpi_struct->src;
//      struct ndpi_id_struct         *dst=ndpi_struct->dst;



	if (flow->l4.tcp.ssh_stage == 0) {
		if (packet->payload_packet_len > 7 && packet->payload_packet_len < 100
			&& memcmp(packet->payload, "SSH-", 4) == 0) {
			NDPI_LOG(NDPI_PROTOCOL_SSH, ndpi_struct, NDPI_LOG_DEBUG, "ssh stage 0 passed\n");
			flow->l4.tcp.ssh_stage = 1 + packet->packet_direction;
			return;
		}
	} else if (flow->l4.tcp.ssh_stage == (2 - packet->packet_direction)) {
		if (packet->payload_packet_len > 7 && packet->payload_packet_len < 100
			&& memcmp(packet->payload, "SSH-", 4) == 0) {
			NDPI_LOG(NDPI_PROTOCOL_SSH, ndpi_struct, NDPI_LOG_DEBUG, "found ssh\n");
			ndpi_int_ssh_add_connection(ndpi_struct, flow);
			return;

		}


	}

	NDPI_LOG(NDPI_PROTOCOL_SSH, ndpi_struct, NDPI_LOG_DEBUG, "excluding ssh at stage %d\n", flow->l4.tcp.ssh_stage);

	NDPI_ADD_PROTOCOL_TO_BITMASK(flow->excluded_protocol_bitmask, NDPI_PROTOCOL_SSH);
}

#endif