--- a/plugins/mod_s2s/s2sout.lib.lua	Fri Jan 22 13:20:00 2016 +0000
+++ b/plugins/mod_s2s/s2sout.lib.lua	Fri Jan 22 14:49:05 2016 +0100
@@ -18,31 +18,13 @@
 local adns = require "net.adns";
 local dns = require "net.dns";
 local t_insert, t_sort, ipairs = table.insert, table.sort, ipairs;
+local local_addresses = require "util.net".local_addresses;
 
 local s2s_destroy_session = require "core.s2smanager".destroy_session;
 
 local log = module._log;
 
-local anysource = { IPv4 = "0.0.0.0", IPv6 = "::" };
-local function get_sources(addrs)
-	local sources = {};
-	for _, IP in ipairs(addrs) do
-		local sock;
-		if IP.proto == "IPv4" then
-			sock = socket.udp();
-		elseif IP.proto == "IPv6" then
-			sock = socket.udp6();
-		end
-		sock:setpeername(IP.addr, 9);
-		local localaddr = sock:getsockname() or anysource[IP.proto];
-		sock:close();
-		if not sources[localaddr] then
-			sources[localaddr] = true;
-			t_insert(sources, new_ip(localaddr, IP.proto));
-		end
-	end
-	return sources;
-end
+local sources = {};
 local has_ipv4, has_ipv6;
 
 local dns_timeout = module:get_option_number("dns_timeout", 15);
@@ -196,7 +178,7 @@
 
 				if have_other_result then
 					if #IPs > 0 then
-						rfc6724_dest(host_session.ip_hosts, get_sources(host_session.ip_hosts));
+						rfc6724_dest(host_session.ip_hosts, sources);
 						for i = 1, #IPs do
 							IPs[i] = {ip = IPs[i], port = connect_port};
 						end
@@ -232,7 +214,7 @@
 
 				if have_other_result then
 					if #IPs > 0 then
-						rfc6724_dest(host_session.ip_hosts, get_sources(host_session.ip_hosts));
+						rfc6724_dest(host_session.ip_hosts, sources);
 						for i = 1, #IPs do
 							IPs[i] = {ip = IPs[i], port = connect_port};
 						end
@@ -320,12 +302,28 @@
 		return;
 	end
 	for source, _ in pairs(s2s_sources) do
-		if source:find(":") then
+		if source == "*" or source == "0.0.0.0" then
+			for _, addr in ipairs(local_addresses("ipv4", true)) do
+				sources[#sources + 1] = new_ip(addr, "IPv4");
+			end
+		elseif source == "::" then
+			for _, addr in ipairs(local_addresses("ipv6", true)) do
+				sources[#sources + 1] = new_ip(addr, "IPv6");
+			end
+		else
+			sources[#sources + 1] = new_ip(source, (source:find(":") and "IPv6") or "IPv4");
+		end
+	end
+	for i = 1,#sources do
+		if sources[i].proto == "IPv6" then
 			has_ipv6 = true;
-		else
+		elseif sources[i].proto == "IPv4" then
 			has_ipv4 = true;
 		end
 	end
+	if not (has_ipv4 or has_ipv6)  then
+		module:log("warn", "No local IPv4 or IPv6 addresses detected, outgoing connections may fail");
+	end
 end);
 
 return s2sout;