From 9f855c60674f5d1929a79d891cf435db3f4f4b42 Mon Sep 17 00:00:00 2001
From: Julius Michaelis <caesar@hg.openclonk.org>
Date: Thu, 5 Jan 2012 23:30:11 +0100
Subject: [PATCH] Add a way to test hosts for their hosting capabilities to the
 masterserver.

---
 .../web/server/include/C4HostTest.php         | 124 ++++++++++++++++++
 masterserver/web/server/include/config.ini    |  12 ++
 masterserver/web/server/index.php             |   8 +-
 3 files changed, 143 insertions(+), 1 deletion(-)
 create mode 100644 masterserver/web/server/include/C4HostTest.php

diff --git a/masterserver/web/server/include/C4HostTest.php b/masterserver/web/server/include/C4HostTest.php
new file mode 100644
index 000000000..5c960d923
--- /dev/null
+++ b/masterserver/web/server/include/C4HostTest.php
@@ -0,0 +1,124 @@
+<?php
+// If not in Include mode: Perform test!
+if(!$C4HostTestIncludeMode)
+	if(performHostTest($_GET['ip'],$_GET['tcp'],$_GET['udp'],$_GET['time']))
+		echo "Reached=Yes\n";
+	else
+		echo "Reached=No\n";
+/**
+ * Parse configuration and call actual host testing.
+ * May open a http connection
+ *
+ * @param string $req Request Data
+ */ 
+function testHostConn(&$req) {
+	global $config;
+	$mode = ParseINI::parseValue('hosttest_mode', $config);
+	if($mode == 0)
+		return true; // Say it works if we didn't test.
+	$timeout = ParseINI::parseValue('hosttest_timeout', $config);
+	$addr = ParseINI::parseValue('Address', $req);
+	preg_match('/TCP:0.0.0.0:([0-9]+),|$/',$addr, $addr_tcp);
+	$tcpport = count($addr_tcp)==2 ? ((int) $addr_tcp[1]) : 0; // Be sure that this is injection safe: this machine might have elevated privilegues on the host test provider based on ip
+	preg_match('/UDP:0.0.0.0:([0-9]+),|$/',$addr, $addr_udp);
+	$udpport = count($addr_udp)==2 ? ((int) $addr_udp[1]) : 0;
+	if(!$udpport && !$tcpport)
+		return false; // That might be a false false, but it's weird anyway.
+	unset($addr, $addr_tcp, $addr_udp);
+	if($mode == 1) { // Perform the check from local host
+		return performHostTest($_SERVER['REMOTE_ADDR'],$tcpport,$udpport,$timeout);
+	} else { // Call hostchecker on remote service
+		$url = ParseINI::parseValue('hosttest_url', $config);
+		$remotetimeout = ParseINI::parseValue('hosttest_remote_timeout', $config);
+		if(!preg_match('#^([a-z.]+\.[a-z]+):([0-9]+)(/.*)$#', $url, $url_split)) {
+			trigger_error('Unable to parse hosttest_url from config.', E_USER_WARNING);
+			return true; // As earlier
+		}
+		$remote_start = microtime(true);
+		$fp = fsockopen($url_split[1], $url_split[2], $errno, $errstr, $remotetimeout);
+		if(!$fp) {
+			trigger_error('Unable to connect to remote C4HostTest '.$url_split[1].':'.$url_split[2]." in $removetimeout secons.", E_USER_WARNING);
+			return true;
+		}
+		$req_str = $url_split[3] . '?remotecall&tcp='.$tcpport.'&udp='.$udpport.'&ip='.$_SERVER['REMOTE_ADDR'].'&time='.$timeout;
+		$remotetimeout += $timeout;	
+		fwrite($fp, "GET ".$req_str." HTTP/1.0\r\nHost: ".$url_split[1]."\r\nUser-Agent: C4Masterserver\r\n\r\n"); // Injection warning!
+		$reply = '';
+		do {
+			stream_set_timeout($fp, $remotetimeout-microtime(true)+$remote_start);
+			$reply .= fread($fp, 8192);
+		} while (!feof($fp) && $remotetimeout > (microtime(true)-$remote_start));
+		if(!preg_match('#^HTTP/1.[01] 200#', $reply)) {
+			trigger_error('Unable to process response from C4HostTest. Wrong address in hosttest_url? No redirects allowed!', E_USER_WARNING);
+			return true;
+		}
+		if(!preg_match('/\r\n\r\n(.*\n)?Reached=[Yy]es\r?\n/s', $reply))
+			return false;
+		return true;
+	}
+}
+/**
+ * Perform host test on $host with $tcpport and $udpport, maximally take $timeout time.
+ *
+ */
+function performHostTest ($host,$tcpport,$udpport,$timeout) {
+	global $C4HostTestIncludeMode;
+	if($tcpport < 1024) 
+		$tcpport = false;
+	if($udpport < 1024)
+		$udpport = false;
+	if($timeout < 0.001) // 0 check
+		return false;
+	if($timeout > 60)
+		$timeout = 60; // Actually, something larger than 30 seconds doesn't make much sense
+	$udpreqhex = array( // Magic UDP data stolen from a capture.
+		0x02, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 
+		0x00, 0x02, 0x00, 0x2b, 0x73, 0x3e, 0xb4, 0x6c, 
+		0xec, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
+		0x00 );
+	$udpreq = '';
+	for($i=0; $i<count($udpreqhex); ++$i) {
+		$udpreq .= chr($udpreqhex[$i]);
+	}
+	$timeend = microtime(true) + $timeout; 
+	$udpreply = false;
+	while(($cyclestart = microtime(true)) < $timeend) {
+		if(!$udp && $udpport)
+			if($udp = @fsockopen('udp://'.$host, $udpport, $udperrno, $udperrstr, 0.1)) // Timeout 1 sec, should theretically not take 'time' at all
+				stream_set_blocking($udp, false);
+		if($udp && !$udpreply) {
+			if(microtime(true) - $lastudppack > $timeout/5) // Send 5 Paks a max, usually because tcp waits for half timeout.
+				fwrite($udp, $udpreq);
+			$lastudppack = microtime(true);
+			$udpreply = fread($udp,1500);
+		}
+		if(!$tcp && $tcpport)
+			$tcp = @fsockopen($host, $tcpport, $tcperrno, $tcperrstr, min($timeout/2 - 0.1, $timeend-microtime(true)));
+		usleep(max(0,min($timeout*1000000/20,microtime(true)-$cylcestart))); // That means 20 cycles limit, even if $stuff goes wrong
+		if ($tcp || $udpreply)
+			break;
+	}
+	if(!$C4HostTestIncludeMode)
+		if($tcperrno && !$tcp)
+			echo "TCP=Error $tcperrno - $tcperrstr\n";
+		else if($tcp) 
+			echo "TCP=Reached\n";
+		else 
+			echo "TCP=Unknown\n"; //Somewhat unbeliegable that UDP replied that quick. 
+	if(!$C4HostTestIncludeMode)
+		if($udperrno && !$udp)
+			echo "UDP=Error $udperrno - $udperrstr\n";
+	if(!$udpreply && $udp)
+		$udpreply = fread($udp,1500); // Last chance udp!
+	if(!$C4HostTestIncludeMode)
+		if(!$tcp && !$udpreply) // we can't say if tcp was just faster, so: ignore
+			echo "UDP=Timeout\n";
+		else if($tcp && !$udpreply)
+			echo "UDP=Unknown\n";
+		else if($udpreply)
+			echo "UDP=Reached\n";
+	return ($tcp || $udpreply); // Reachable if a tcp connection could be made, udp replied
+}
+?>
diff --git a/masterserver/web/server/include/config.ini b/masterserver/web/server/include/config.ini
index 3b0e76e7a..ff8da07aa 100644
--- a/masterserver/web/server/include/config.ini
+++ b/masterserver/web/server/include/config.ini
@@ -46,3 +46,15 @@ oc_update_url=http://www.example.com/
 
 ;secret key for the HAMC-updating system (using sha256) to verify files
 oc_update_secret=
+
+;host port testing: 0 - off (default), 1 - perfrom from local host, 2 - perform from from hosttest_url
+hosttest_mode=0
+
+;time for the client to reply - keep in mind that if that test fails, a client will have to wait at least that long.
+hosttest_timeout=6
+
+;remote address of host testing script, supply in format of masterserver address in oc config
+hosttest_url=
+
+;hosttest provider answer time. Additional time that may be consumed by establishing the http connection, etc.
+hosttest_remote_timeout=1.5
diff --git a/masterserver/web/server/index.php b/masterserver/web/server/index.php
index bab834a7e..a3cd250f8 100644
--- a/masterserver/web/server/index.php
+++ b/masterserver/web/server/index.php
@@ -14,6 +14,8 @@ require_once('include/C4Masterserver.php');
 require_once('include/C4Network.php');
 require_once('include/FloodProtection.php');
 require_once('include/ParseINI.php');
+$C4HostTestIncludeMode = true;
+require_once('include/C4HostTest.php');
 
 $config = file_get_contents('include/config.ini');
 $link = mysql_connect(
@@ -85,7 +87,11 @@ if ($link && $db) {
 				} else {
 					$csid = $server->addReference($reference);
 					if ($csid) {
-						C4Network::sendAnswer(C4Network::createAnswer(array('Status' => 'Success', 'CSID' => $csid)));
+						$answer = array('Status' => 'Success', 'CSID' => $csid);
+						if(!testHostConn($input))
+							$answer['Message'] = 'Your network failed to pass certain tests. It is unlikely that are you able to host for the public.|To fix that, you need port forwarding in your router.';
+						C4Network::sendAnswer(C4Network::createAnswer($answer));
+						unset($answer);
 					} else {
 						C4Network::sendAnswer(C4Network::createError('Round signup failed. (To many tries?)'));
 					}