Add redirect check

ReadMe.md

@@ -216,6 +216,9 @@ Non-authoritative answer:
 * 如已经安装chinaDNS，建议将chinaDNS的上游配置为SmartDNS。
 * SmartDNS默认情况，将53端口的请求转发到SmartDNS的本地端口，由`Redirect`配置选项控制。
 
+6. 界面提示重定向失败：
+* openwrt 15.01系统不支持IPV6重定向，如网络需要支持IPV6，请将DNSMASQ上游改为smartdns，或者将smartdns的端口改为53，并停用dnsmasq。
+* LEDE之后系统，请安装IPV6的nat转发驱动。点击`system`->`Software`，点击`update lists`更新软件列表后，安装`ip6tables-mod-nat`
 
 华硕路由器原生固件
 --------------

package/luci/files/luci/controller/smartdns.lua

@@ -1,6 +1,7 @@
 -- Copyright 2018 Nick Peng (pymumu@gmail.com)
 
 module("luci.controller.smartdns", package.seeall)
+local smartdns = require "luci.model.smartdns"
 
 function index()
 	if not nixio.fs.access("/etc/config/smartdns") then
@@ -17,9 +18,23 @@ end
 local function is_running()
 	return luci.sys.call("pidof smartdns >/dev/null") == 0
 end
+
 function act_status()
 	local e={}
+	e.ipv6_works = 2;
+	e.ipv4_works = 2;
+	e.redirect = smartdns.get_config_option("smartdns", "smartdns", "redirect", nil);
+	e.local_port = smartdns.get_config_option("smartdns", "smartdns", "port", nil);
+	if e.redirect == "1" then 
+		if e.local_port ~= nil and e.local_port ~= "53" then
+			e.ipv4_works = luci.sys.call("iptables -t nat -nL PREROUTING | grep REDIRECT | grep dpt:53 | grep %q >/dev/null 2>&1" % e.local_port) == 0
+			e.ipv6_works = luci.sys.call("ip6tables -t nat -nL PREROUTING | grep REDIRECT | grep dpt:53 | grep %q >/dev/null 2>&1" % e.local_port) == 0
+		else
+			e.redirect = 0
+		end
+	end
 	e.running = is_running()
+
 	luci.http.prepare_content("application/json")
 	luci.http.write_json(e)
 end

package/luci/files/luci/i18n/smartdns.zh-cn.po

@@ -31,6 +31,12 @@ msgstr "本地端口"
 msgid "Smartdns local server port"
 msgstr "SmartDNS本地服务端口"
 
+msgid "IPV4 53 Port Redirect Failure"
+msgstr "IPV4 53端口重定向失败"
+
+msgid "IPV6 53 Port Redirect Failure"
+msgstr "IPV6 53端口重定向失败"
+
 msgid "Redirect"
 msgstr "重定向"
 

package/luci/files/luci/model/smartdns.lua

@@ -0,0 +1,17 @@
+-- Copyright 2018 Nick Peng (pymumu@gmail.com)
+
+require ("nixio.fs")
+require ("luci.http")
+require ("luci.dispatcher")
+require ("nixio.fs")
+
+local uci = require "luci.model.uci".cursor()
+
+module("luci.model.smartdns", package.seeall)
+
+function get_config_option(module, section, option, default)
+	return uci:get_first(module, section, option) or default
+end
+
+return m
+

package/luci/files/luci/view/smartdns/smartdns_status.htm

@@ -3,12 +3,23 @@ XHR.poll(3, '<%=luci.dispatcher.build_url("admin", "services", "smartdns", "stat
 	function(x, data) {
 		var tb = document.getElementById('smartdns_status');
 		if (data && tb) {
+			var links = "";
 			if (data.running) {
-				var links = '<b><font color=green>SmartDNS - <%:RUNNING%></font></b></em>';
+				links = '<b><font color=green>SmartDNS - <%:RUNNING%></font></b></em>';
-				tb.innerHTML = links;
+				if (data.redirect && data.redirect == 1) {
+					if (data.ipv4_works == 0) {
+						links += "<br></br><b><font color=red><%:IPV4 53 Port Redirect Failure%></font></b>"
+					}
+
+					if (data.ipv6_works == 0) {
+						links += "<br></br><b><font color=red><%:IPV6 53 Port Redirect Failure%></font></b>"
+					}
+				}
 			} else {
-				tb.innerHTML = '<b><font color=red>SmartDNS - <%:NOT RUNNING%></font></b>';
+				links = '<b><font color=red>SmartDNS - <%:NOT RUNNING%></font></b>';
 			}
+
+			tb.innerHTML = links;
 		}
 	}
 );

package/openwrt/files/etc/init.d/smartdns

@@ -18,6 +18,12 @@ set_iptable()
 		iptables -t nat -A PREROUTING -p udp -d $IP --dport 53 -j REDIRECT --to-ports $SMARTDNS_PORT >/dev/null 2>&1
 	done
 
+	IPS="`ifconfig | grep "inet6 addr" | grep -v " fe80::" | grep -v " ::1" | grep "Global" | awk '{print $3}'`"
+	for IP in $IPS
+	do
+		ip6tables -t nat -A PREROUTING -p udp -d $IP --dport 53 -j REDIRECT --to-ports $SMARTDNS_PORT >/dev/null 2>&1
+	done
+
 }
 
 clear_iptable()
@@ -27,6 +33,12 @@ clear_iptable()
 	do
 		iptables -t nat -D PREROUTING -p udp -d $IP --dport 53 -j REDIRECT --to-ports $SMARTDNS_PORT >/dev/null 2>&1
 	done
+
+	IPS="`ifconfig | grep "inet6 addr" | grep -v " fe80::" | grep -v " ::1" | grep "Global" | awk '{print $3}'`"
+	for IP in $IPS
+	do
+		ip6tables -t nat -D PREROUTING -p udp -d $IP --dport 53 -j REDIRECT --to-ports $SMARTDNS_PORT >/dev/null 2>&1
+	done
 	
 }