op-packages/luci-app-passwall/root/usr/share/passwall/socks_auto_switch.sh

#!/bin/sh

. /usr/share/passwall/utils.sh
APP_FILE=${APP_PATH}/app.sh

flag=0

check_process() {
	while busybox pgrep -af "${CONFIG}/" | grep -E 'app\.sh.*(start|stop)|nftables\.sh|iptables\.sh|subscribe\.lua' >/dev/null; do
		sleep 6s
	done
}

test_url() {
	local url="$1"
	local try="${2:-1}"
	local timeout="${3:-2}"
	local extra_params="$4"
	local repeat="$5"

	if [ -z "$curl_retry_all_errors" ]; then
		if /usr/bin/curl --help all | grep -q "\-\-retry-all-errors"; then
			curl_retry_all_errors=1
		fi
	fi
	[ "$curl_retry_all_errors" = "1" ] && extra_params="--retry-all-errors ${extra_params}"

	local max_time=$((timeout * (try + 1) + try + 3))
	curl_test() {
		/usr/bin/curl -skIL -o /dev/null ${extra_params} --max-time ${max_time} --connect-timeout ${timeout} --retry ${try} --retry-delay 1 -w "%{http_code}" "$url"
	}

	local status=$(curl_test)
	[ "$status" = "204" ] && status=200
	if [ "$status" = "200" ] && [ "$repeat" = "1" ]; then
		sleep 3s
		status=$(curl_test)
		[ "$status" = "204" ] && status=200
	fi
	echo $status
}

test_proxy() {
	local result=0
	local status=$(test_url "${probe_url}" ${retry_num} ${connect_timeout} "-x socks5h://127.0.0.1:${socks_port}")
	if [ "$status" = "200" ]; then
		result=0
	else
		local status2=$(test_url "https://www.baidu.com" ${retry_num} ${connect_timeout})
		if [ "$status2" = "200" ]; then
			result=1
		else
			result=2
			ping -c 3 -W 1 223.5.5.5 > /dev/null 2>&1
			[ $? -eq 0 ] && {
				result=1
			}
		fi
	fi
	echo $result
}

test_node() {
	local node_id=$1
	local _type=$(echo $(config_n_get ${node_id} type) | tr 'A-Z' 'a-z')
	[ -n "${_type}" ] && {
		check_process
		local _tmp_port=$(get_new_port 48800 tcp,udp)
		NO_REC_PROCESS=1 $APP_FILE run_socks flag="test_node_${node_id}" node=${node_id} bind=127.0.0.1 socks_port=${_tmp_port} config_file=test_node_${node_id}.json
		sleep 2s
		local curlx="socks5h://127.0.0.1:${_tmp_port}"
		local _proxy_status=$(test_url "${probe_url}" ${retry_num} ${connect_timeout} "-x $curlx" 1)
		# 结束 SS 插件进程
		local pid_file="/tmp/etc/${CONFIG}/test_node_${node_id}_plugin.pid"
		[ -s "$pid_file" ] && kill -9 "$(head -n 1 "$pid_file")" >/dev/null 2>&1
		busybox pgrep -af "test_node_${node_id}" | awk '! /socks_auto_switch\.sh/{print $1}' | xargs kill -9 >/dev/null 2>&1
		rm -rf /tmp/etc/${CONFIG}/test_node_${node_id}*.*
		if [ "${_proxy_status}" -eq 200 ]; then
			return 0
		fi
	}
	return 1
}

try_switch_backup() {
	local b_nodes="$1"
	local now_node="$2"
	local total tried
	local new_node msg
	local first_node found node

	# 只有一个后备节点时，与主节点轮询
	if [ "$backup_node_num" -eq 1 ]; then
		b_nodes="$b_nodes $main_node"
	fi

	total=$(printf "%s\n" "$b_nodes" | wc -w)
	tried=0

	while [ "$tried" -lt "$total" ]; do
		new_node=""
		first_node=""
		found=""
		for node in $b_nodes; do
			[ -z "$first_node" ] && first_node="$node"         # 记录第一个节点
			[ "$found" = "1" ] && { new_node="$node"; break; } # 找到当前节点后取下一个
			[ "$node" = "$now_node" ] && found=1               # 标记找到当前节点
		done
		# 如果没找到当前节点，或者当前节点是最后一个，就取第一个节点
		[ -z "$new_node" ] && new_node="$first_node"

		local node_role node_type node_remarks
		if [ "$new_node" = "$main_node" ]; then
			node_role="主节点"
		else
			node_role="后备节点"
		fi
		node_type=$(config_n_get $new_node type)
		node_remarks=$(config_n_get $new_node remarks)
		echolog "Socks切换检测：端口[${socks_port}] 尝试${node_role}【${node_type}：[$node_remarks]】"

		if test_node ${new_node}; then
			check_process
			echolog "Socks切换检测：端口[${socks_port}]【${node_type}：[$node_remarks]】正常，切换到此节点！"
			NO_REC_PROCESS=1 $APP_FILE socks_node_switch flag=${id} new_node=${new_node}
			[ $? -eq 0 ] && {
				echolog "Socks切换检测：端口[${socks_port}] 节点切换完毕！"
			}
			return 0
		fi
		echolog "Socks切换检测：端口[${socks_port}]【${node_type}：[$node_remarks]】异常。"
		now_node="$new_node"
		tried=$((tried + 1))
	done

	echolog "Socks切换检测：端口[${socks_port}] 所有节点均不可用！"
	return 1
}

test_auto_switch() {
	flag=$((flag + 1))
	local b_nodes=$1
	local now_node=$2
	[ -z "$now_node" ] && {
		if [ -n "$(get_cache_var "${id}")" ]; then
			now_node=$(get_cache_var "${id}")
		else
			#echolog "Socks切换检测：未知错误"
			return 1
		fi
	}

	[ $flag -le 1 ] && main_node=$now_node

	local status=$(test_proxy)
	if [ "$status" = "2" ]; then
		echolog "Socks切换检测：无法连接到网络，请检查网络是否正常！"
		return 2
	fi

	#检测主节点是否能使用
	if [ "$restore_switch" = "1" ] && [ -n "$main_node" ] && [ "$now_node" != "$main_node" ]; then
		test_node ${main_node}
		[ $? -eq 0 ] && {
			check_process
			echolog "Socks切换检测：端口[${socks_port}] 主节点【$(config_n_get $main_node type)：[$(config_n_get $main_node remarks)]】正常，切换到主节点！"
			NO_REC_PROCESS=1 $APP_FILE socks_node_switch flag=${id} new_node=${main_node}
			[ $? -eq 0 ] && echolog "Socks切换检测：端口[${socks_port}] 节点切换完毕！"
			return 0
		}
	fi

	[ "$status" = "0" ] && {
		#echolog "Socks切换检测：${id}【$(config_n_get $now_node type)：[$(config_n_get $now_node remarks)]】正常。"
		return 0
	}

	echolog "Socks切换检测：端口[${socks_port}]【$(config_n_get $now_node type)：[$(config_n_get $now_node remarks)]】异常。"
	try_switch_backup "$b_nodes" "$now_node"
	return $?
}

start() {
	id=$1
	LOCK_FILE=${LOCK_PATH}/${CONFIG}_socks_auto_switch_${id}.lock
	LOG_EVENT_FILTER=$(uci -q get "${CONFIG}.global[0].log_event_filter" 2>/dev/null)
	LOG_EVENT_CMD=$(uci -q get "${CONFIG}.global[0].log_event_cmd" 2>/dev/null)
	main_node=$(config_n_get $id node)
	socks_port=$(config_n_get $id port 0)
	delay=$(config_n_get $id autoswitch_testing_time 30)
	connect_timeout=$(config_n_get $id autoswitch_connect_timeout 3)
	retry_num=$(config_n_get $id autoswitch_retry_num 1)
	restore_switch=$(config_n_get $id autoswitch_restore_switch 0)
	probe_url=$(config_n_get $id autoswitch_probe_url "https://www.google.com/generate_204")
	backup_node=$(lua_api "get_socks_backup_nodes(\"${id}\")")
	if [ -n "$backup_node" ]; then
		backup_node_num=$(printf "%s\n" "$backup_node" | wc -w)
		echolog "  - Socks切换检测：端口[${socks_port}] 后备节点数量：${backup_node_num}"
		if [ "$backup_node_num" -eq 1 ]; then
			[ "$main_node" = "$backup_node" ] && return
		elif [ "$backup_node_num" -gt 1 ]; then
			[ "$restore_switch" != "1" ] && {
				[ -z "$(echo $backup_node | grep -F "$main_node")" ] && backup_node="${backup_node} ${main_node}"
			}
		fi
	else
		echolog "  - Socks切换检测：端口[${socks_port}] 后备节点数量：0"
		return
	fi
	while [ -n "$backup_node" ]; do
		[ -f "$LOCK_FILE" ] && {
			sleep 6s
			continue
		}
		check_process
		touch $LOCK_FILE
		test_auto_switch "$backup_node"
		rm -f $LOCK_FILE
		sleep ${delay}
	done
}

start $@