/*
** Zabbix
** Copyright (C) 2001-2016 Zabbix SIA
**
** 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.
**/

#include "common.h"
#include "poller/checks_agent.h"
#include "poller/checks_ipmi.h"
#include "poller/checks_ssh.h"
#include "poller/checks_telnet.h"
#include "zbxexec.h"
#include "zbxserver.h"
#include "db.h"
#include "log.h"

#include "scripts.h"

extern int	CONFIG_TRAPPER_TIMEOUT;

static int	zbx_execute_script_on_agent(DC_HOST *host, const char *command, char **result,
		char *error, size_t max_error_len)
{
	const char	*__function_name = "zbx_execute_script_on_agent";
	int		ret;
	AGENT_RESULT	agent_result;
	char		*param, *port = NULL;
	DC_ITEM		item;

	zabbix_log(LOG_LEVEL_DEBUG, "In %s()", __function_name);

	*error = '\0';
	memset(&item, 0, sizeof(item));
	memcpy(&item.host, host, sizeof(item.host));

	if (SUCCEED != (ret = DCconfig_get_interface_by_type(&item.interface, host->hostid, INTERFACE_TYPE_AGENT)))
	{
		zbx_snprintf(error, max_error_len, "Zabbix agent interface is not defined for host [%s]", host->host);
		goto fail;
	}

	port = zbx_strdup(port, item.interface.port_orig);
	substitute_simple_macros(NULL, NULL, NULL, NULL, &host->hostid, NULL, NULL, &port, MACRO_TYPE_COMMON, NULL, 0);

	if (SUCCEED != (ret = is_ushort(port, &item.interface.port)))
	{
		zbx_snprintf(error, max_error_len, "Invalid port number [%s]", item.interface.port_orig);
		goto fail;
	}

	param = zbx_dyn_escape_string(command, "\"");
	item.key = zbx_dsprintf(item.key, "system.run[\"%s\",\"%s\"]", param, NULL == result ? "nowait" : "wait");
	item.value_type = ITEM_VALUE_TYPE_TEXT;
	zbx_free(param);

	init_result(&agent_result);

	alarm(CONFIG_TIMEOUT);

	if (SUCCEED != (ret = get_value_agent(&item, &agent_result)))
	{
		if (ISSET_MSG(&agent_result))
			zbx_strlcpy(error, agent_result.msg, max_error_len);
		ret = FAIL;
	}
	else if (NULL != result && ISSET_TEXT(&agent_result))
		*result = zbx_strdup(*result, agent_result.text);

	alarm(0);

	free_result(&agent_result);

	zbx_free(item.key);
fail:
	zbx_free(port);

	zabbix_log(LOG_LEVEL_DEBUG, "End of %s():%s", __function_name, zbx_result_string(ret));

	return ret;
}

#ifdef HAVE_OPENIPMI
static int	zbx_execute_ipmi_command(DC_HOST *host, const char *command, char *error, size_t max_error_len)
{
	const char	*__function_name = "zbx_execute_ipmi_command";
	int		val, ret;
	char		*port = NULL;
	DC_ITEM		item;

	zabbix_log(LOG_LEVEL_DEBUG, "In %s()", __function_name);

	*error = '\0';
	memset(&item, 0, sizeof(item));
	memcpy(&item.host, host, sizeof(item.host));

	if (SUCCEED != (ret = DCconfig_get_interface_by_type(&item.interface, host->hostid, INTERFACE_TYPE_IPMI)))
	{
		zbx_snprintf(error, max_error_len, "IPMI interface is not defined for host [%s]", host->host);
		goto fail;
	}

	port = zbx_strdup(port, item.interface.port_orig);
	substitute_simple_macros(NULL, NULL, NULL, NULL, &host->hostid, NULL, NULL, &port, MACRO_TYPE_COMMON, NULL, 0);

	if (SUCCEED != (ret = is_ushort(port, &item.interface.port)))
	{
		zbx_snprintf(error, max_error_len, "invalid port number [%s]", item.interface.port_orig);
		goto fail;
	}

	if (SUCCEED == (ret = parse_ipmi_command(command, item.ipmi_sensor, &val, error, max_error_len)))
	{
		if (SUCCEED != (ret = set_ipmi_control_value(&item, val, error, max_error_len)))
			ret = FAIL;
	}
fail:
	zbx_free(port);

	zabbix_log(LOG_LEVEL_DEBUG, "End of %s():%s", __function_name, zbx_result_string(ret));

	return ret;
}
#endif

static int	zbx_execute_script_on_terminal(DC_HOST *host, zbx_script_t *script, char **result,
		char *error, size_t max_error_len)
{
	const char	*__function_name = "zbx_execute_script_on_terminal";
	int		ret;
	AGENT_RESULT	agent_result;
	DC_ITEM		item;
	int             (*function)();

#ifdef HAVE_SSH2
	assert(ZBX_SCRIPT_TYPE_SSH == script->type || ZBX_SCRIPT_TYPE_TELNET == script->type);
#else
	assert(ZBX_SCRIPT_TYPE_TELNET == script->type);
#endif

	zabbix_log(LOG_LEVEL_DEBUG, "In %s()", __function_name);

	*error = '\0';
	memset(&item, 0, sizeof(item));
	memcpy(&item.host, host, sizeof(item.host));

	if (SUCCEED != (ret = DCconfig_get_interface_by_type(&item.interface, host->hostid, INTERFACE_TYPE_AGENT)))
	{
		zbx_snprintf(error, max_error_len, "Zabbix agent interface is not defined for host [%s]", host->host);
		goto fail;
	}

	switch (script->type)
	{
		case ZBX_SCRIPT_TYPE_SSH:
			item.authtype = script->authtype;
			item.publickey = script->publickey;
			item.privatekey = script->privatekey;
			/* break; is not missing here */
		case ZBX_SCRIPT_TYPE_TELNET:
			item.username = script->username;
			item.password = script->password;
			break;
	}

	substitute_simple_macros(NULL, NULL, NULL, NULL, &host->hostid, NULL, NULL,
			&script->port, MACRO_TYPE_COMMON, NULL, 0);

	if ('\0' != *script->port && SUCCEED != (ret = is_ushort(script->port, NULL)))
	{
		zbx_snprintf(error, max_error_len, "Invalid port number [%s]", script->port);
		goto fail;
	}

#ifdef HAVE_SSH2
	if (ZBX_SCRIPT_TYPE_SSH == script->type)
	{
		item.key = zbx_dsprintf(item.key, "ssh.run[,,%s]", script->port);
		function = get_value_ssh;
	}
	else
	{
#endif
		item.key = zbx_dsprintf(item.key, "telnet.run[,,%s]", script->port);
		function = get_value_telnet;
#ifdef HAVE_SSH2
	}
#endif
	item.value_type = ITEM_VALUE_TYPE_TEXT;
	item.params = zbx_strdup(item.params, script->command);

	init_result(&agent_result);

	alarm(CONFIG_TIMEOUT);

	if (SUCCEED != (ret = function(&item, &agent_result)))
	{
		if (ISSET_MSG(&agent_result))
			zbx_strlcpy(error, agent_result.msg, max_error_len);
		ret = FAIL;
	}
	else if (NULL != result && ISSET_TEXT(&agent_result))
		*result = zbx_strdup(*result, agent_result.text);

	alarm(0);

	free_result(&agent_result);

	zbx_free(item.params);
	zbx_free(item.key);
fail:
	zabbix_log(LOG_LEVEL_DEBUG, "End of %s():%s", __function_name, zbx_result_string(ret));

	return ret;
}

static int	DBget_script_by_scriptid(zbx_uint64_t scriptid, zbx_script_t *script, zbx_uint64_t *groupid)
{
	const char	*__function_name = "DBget_script_by_scriptid";
	DB_RESULT	result;
	DB_ROW		row;
	int		ret = FAIL;

	zabbix_log(LOG_LEVEL_DEBUG, "In %s()", __function_name);

	result = DBselect(
			"select type,execute_on,command,groupid"
			" from scripts"
			" where scriptid=" ZBX_FS_UI64,
			scriptid);

	if (NULL != (row = DBfetch(result)))
	{
		script->type = (unsigned char)atoi(row[0]);
		script->execute_on = (unsigned char)atoi(row[1]);
		script->command = zbx_strdup(script->command, row[2]);
		ZBX_DBROW2UINT64(*groupid, row[3]);
		ret = SUCCEED;
	}
	DBfree_result(result);

	zabbix_log(LOG_LEVEL_DEBUG, "End of %s():%s", __function_name, zbx_result_string(ret));

	return ret;
}

static int	check_script_permissions(zbx_uint64_t groupid, zbx_uint64_t hostid, char *error, size_t max_error_len)
{
	const char	*__function_name = "check_script_permissions";
	DB_RESULT	result;
	int		ret = SUCCEED;

	zabbix_log(LOG_LEVEL_DEBUG, "In %s() groupid:" ZBX_FS_UI64 " hostid:" ZBX_FS_UI64,
			__function_name, groupid, hostid);

	if (0 == groupid)
		goto exit;

	result = DBselect(
			"select hostid"
			" from hosts_groups"
			" where hostid=" ZBX_FS_UI64
				" and groupid=" ZBX_FS_UI64,
			hostid, groupid);

	if (NULL == DBfetch(result))
	{
		zbx_strlcpy(error, "Insufficient permissions. Host is not in an allowed host group.", max_error_len);
		ret = FAIL;
	}
	DBfree_result(result);
exit:
	zabbix_log(LOG_LEVEL_DEBUG, "End of %s():%s", __function_name, zbx_result_string(ret));

	return ret;
}

void	zbx_script_init(zbx_script_t *script)
{
	memset(script, 0, sizeof(zbx_script_t));
}

void	zbx_script_clean(zbx_script_t *script)
{
	zbx_free(script->port);
	zbx_free(script->username);
	zbx_free(script->publickey);
	zbx_free(script->privatekey);
	zbx_free(script->password);
	zbx_free(script->command);
}

/******************************************************************************
 *                                                                            *
 * Function: zbx_execute_script                                               *
 *                                                                            *
 * Purpose: executing user scripts or remote commands                         *
 *                                                                            *
 * Return value:  SUCCEED - processed successfully                            *
 *                FAIL - an error occurred                                    *
 *                TIMEOUT_ERROR - a timeout occurred                          *
 *                                                                            *
 * Comments: !!! always call 'zbx_script_clean' function after                *
 *           'zbx_execute_script' to clear allocated memory                   *
 *                                                                            *
 ******************************************************************************/
int	zbx_execute_script(DC_HOST *host, zbx_script_t *script, char **result, char *error, size_t max_error_len)
{
	const char	*__function_name = "zbx_execute_script";
	int		ret = FAIL;
	zbx_uint64_t	groupid;

	zabbix_log(LOG_LEVEL_DEBUG, "In %s()", __function_name);

	*error = '\0';

	switch (script->type)
	{
		case ZBX_SCRIPT_TYPE_CUSTOM_SCRIPT:
			dos2unix(script->command);	/* CR+LF (Windows) => LF (Unix) */

			switch (script->execute_on)
			{
				case ZBX_SCRIPT_EXECUTE_ON_AGENT:
					ret = zbx_execute_script_on_agent(host, script->command, result,
							error, max_error_len);
					break;
				case ZBX_SCRIPT_EXECUTE_ON_SERVER:
					ret = zbx_execute(script->command, result, error, max_error_len,
							CONFIG_TRAPPER_TIMEOUT);
					break;
				default:
					zbx_snprintf(error, max_error_len, "Invalid 'Execute on' option [%d]",
							(int)script->execute_on);
			}
			break;
		case ZBX_SCRIPT_TYPE_IPMI:
#ifdef HAVE_OPENIPMI
			if (SUCCEED == (ret = zbx_execute_ipmi_command(host, script->command, error, max_error_len)))
			{
				if (NULL != result)
					*result = zbx_strdup(*result, "IPMI command successfully executed");
			}
#else
			zbx_strlcpy(error, "Support for IPMI commands was not compiled in", max_error_len);
#endif
			break;
		case ZBX_SCRIPT_TYPE_SSH:
#ifdef HAVE_SSH2
			substitute_simple_macros(NULL, NULL, NULL, NULL, &host->hostid, NULL, NULL,
					&script->publickey, MACRO_TYPE_COMMON, NULL, 0);
			substitute_simple_macros(NULL, NULL, NULL, NULL, &host->hostid, NULL, NULL,
					&script->privatekey, MACRO_TYPE_COMMON, NULL, 0);
			/* break; is not missing here */
#else
			zbx_strlcpy(error, "Support for SSH script was not compiled in", max_error_len);
			break;
#endif
		case ZBX_SCRIPT_TYPE_TELNET:
			substitute_simple_macros(NULL, NULL, NULL, NULL, &host->hostid, NULL, NULL,
					&script->username, MACRO_TYPE_COMMON, NULL, 0);
			substitute_simple_macros(NULL, NULL, NULL, NULL, &host->hostid, NULL, NULL,
					&script->password, MACRO_TYPE_COMMON, NULL, 0);

			ret = zbx_execute_script_on_terminal(host, script, result, error, max_error_len);
			break;
		case ZBX_SCRIPT_TYPE_GLOBAL_SCRIPT:
			if (SUCCEED != DBget_script_by_scriptid(script->scriptid, script, &groupid))
			{
				zbx_snprintf(error, max_error_len,
						"Unknown Script ID [" ZBX_FS_UI64 "]", script->scriptid);
				break;
			}

			if (SUCCEED == check_script_permissions(groupid, host->hostid, error, max_error_len))
			{
				substitute_simple_macros(NULL, NULL, NULL, NULL, NULL, host, NULL,
						&script->command, MACRO_TYPE_SCRIPT, NULL, 0);

				ret = zbx_execute_script(host, script, result, error, max_error_len);	/* recursion */
			}
			break;
		default:
			zbx_snprintf(error, max_error_len, "Invalid command type [%d]", (int)script->type);
	}

	if (SUCCEED != ret && NULL != result)
		*result = zbx_strdup(*result, "");

	zabbix_log(LOG_LEVEL_DEBUG, "End of %s():%s", __function_name, zbx_result_string(ret));

	return ret;
}
