PHP+Flex实现多人聊天之服务端（解决安全沙箱问题）

说明：

客户端在第一次请求service的时候，会事先发送安全信息请求验证，因此当你捕获到“policy-file-request”的时候，直接返回策略文件信息："<?xml version=\"1.0\"?><cross-domain-policy><site-control permitted-cross-domain-policies=\"all\"/><allow-access-from domain=\"*\" to-ports=\"*\"/></cross-domain-policy>\0"。此时，客户端会另外开一个连接请求service。这样就可以同过安全沙箱验证了。

跟踪service端信息：

2010-06-21 16:30:47 Listening on port 10000. Server started at 16:30:47
2010-06-21 16:30:54 New connection ( 0 ) from 192.168.17.55 on port 1872
2010-06-21 16:30:54 Received 'policy-file-request' from 0
2010-06-21 16:30:54 sending: "<?xml version="1.0"?><cross-domain-policy><site-control permitted-cross-domain-policies="all"/><allow-access-from domain="*" to-ports="*"/></cross-domain-policy>" to: 0
2010-06-21 16:30:54 Closed connection ( 0 ) from 192.168.17.55 on port 1872
2010-06-21 16:30:54 New connection ( 0 ) from 192.168.17.55 on port 1873

代码如下：

<?PHP
/**
* patServer
* PHP socket server base class
* Events that can be handled:
*   * onStart
*   * onConnect
*   * onConnectionRefused
*   * onClose
*   * onShutdown
*   * onReceiveData
*
* @version 1.1
* @author   Stephan Schmidt <[e-mail]>
* @package patServer
*/
class patServer{
    /**
* information about the project
* @var array $systemVars
*/
    var $systemVars   = array(

    "appName"   => "patServer",
    "appVersion"   => "1.1",
    "author"   => array("Stephan Schmidt <[e-mail]>", )
    );

    /**
* port to listen
* @var integer   $port
*/
    var $port   = 10000;

    /**
* domain to bind to
* @var string $domain
*/
    var $domain   = "localhost";

    /**
* maximum amount of clients
* @var integer $maxClients
*/
    var $maxClients = -1;

    /**
* buffer size for socket_read
* @var integer $readBufferSize
*/
    var $readBufferSize   = 128;

    /**
* end character for socket_read
* @var integer $readEndCharacter
*/
    var $readEndCharacter = "\n";

    /**
* maximum of backlog in queue
* @var integer $maxQueue
*/
    var $maxQueue = 500;

    /**
* debug mode
* @var boolean $debug
*/
    var $debug   = true;

    /**
* debug mode
* @var string $debugMode
*/
    var $debugMode = "text";

    /**
* debug destination (filename or stdout)
* @var string $debugDest
*/
    var $debugDest = "stdout";

    /**
* empty array, used for socket_select
* @var array $null
*/
    var $null   = array();

    /**
* all file descriptors are stored here
* @var array $clientFD
*/
    var $clientFD = array();

    /**
* needed to store client information
* @var array $clientInfo
*/
    var $clientInfo = array();

    /**
* needed to store server information
* @var array $serverInfo
*/
    var $serverInfo = array();

    /**
* amount of clients
* @var integer   $clients
*/
    var $clients = 0;

    /**
* create a new socket server
*
* @access public
* @param string   $domain   domain to bind to
* @param integer   $port   port to listen to
*/
    function patServer( $domain = "localhost", $port = 8083 ){
        $this->domain = $domain;
        $this->port   = $port;

        $this->serverInfo["domain"]         = $domain;
        $this->serverInfo["port"]         = $port;
        $this->serverInfo["servername"]     = $this->systemVars["appName"];
        $this->serverInfo["serverversion"] = $this->systemVars["appVersion"];
//        $this->readEndCharacter = chr('0');

        set_time_limit( 0 );
    }

    /**
* set maximum amount of simultaneous connections
*
* @access public
* @param int $maxClients
*/
    function setMaxClients( $maxClients ){
        $this->maxClients = $maxClients;
    }

    /**
* set debug mode
*
* @access public
* @param mixed $debug [text|htmlfalse]
* @param string $dest destination of debug message (stdout to output or filename if log should be written)
*/
    function setDebugMode( $debug, $dest = "stdout" ){
        if( $debug === false ){
            $this->debug = false;
            return true;
        }

        $this->debug   = true;
        $this->debugMode = $debug;
        $this->debugDest = $dest;
    }

    /**
* start the server
*
* @access public
* @param int $maxClients
*/
    function start(){
        $this->initFD = @socket_create( AF_INET, SOCK_STREAM, 0 );
        if( !$this->initFD )
        die( "patServer: Could not create socket." );

        // adress may be reused
        socket_setopt( $this->initFD, SOL_SOCKET, SO_REUSEADDR, 1 );

        // bind the socket
        if( !@socket_bind( $this->initFD, $this->domain, $this->port ) ){
            @socket_close( $this->initFD );
            die( "patServer: Could not bind socket to ".$this->domain." on port ".$this->port." ( ".$this->getLastSocketError( $this->initFd )." )." );
        }

        // listen on selected port
        if( !@socket_listen( $this->initFD, $this->maxQueue ) )
        die( "patServer: Could not listen ( ".$this->getLastSocketError( $this->initFd )." )." );

        $this->sendDebugMessage( "Listening on port ".$this->port.". Server started at ".date( "H:i:s", time() ) );

        // this allows the shutdown function to check whether the server is already shut down
        $GLOBALS["_patServerStatus"] = "running";
        // this ensures that the server will be sutdown correctly
        register_shutdown_function( array( $this, "shutdown" ) );

        if( method_exists( $this, "onStart" ) )
        $this->onStart();

        $this->serverInfo["started"] = time();
        $this->serverInfo["status"]   = "running";

        while( true ){
            $readFDs = array();
            array_push( $readFDs, $this->initFD );

            // fetch all clients that are awaiting connections
            for( $i = 0; $i < count( $this->clientFD ); $i++ )
            if( isset( $this->clientFD[$i] ) )
            array_push( $readFDs, $this->clientFD[$i] );

            // block and wait for data or new connection
            $ready = @socket_select( $readFDs, $this->null, $this->null, NULL );

            if( $ready === false ){
                $this->sendDebugMessage( "socket_select failed." );
                $this->shutdown();
            }

            // check for new connection
            if( in_array( $this->initFD, $readFDs ) ){
                $newClient = $this->acceptConnection( $this->initFD );

                // check for maximum amount of connections
                if( $this->maxClients > 0 ){
                    if( $this->clients > $this->maxClients ){
                        $this->sendDebugMessage( "Too many connections." );

                        if( method_exists( $this, "onConnectionRefused" ) )
                        $this->onConnectionRefused( $newClient );

                        $this->closeConnection( $newClient );
                    }
                }

                if( --$ready <= 0 )
                continue;
            }

            // check all clients for incoming data
            for( $i = 0; $i < count( $this->clientFD ); $i++ ){
                if( !isset( $this->clientFD[$i] ) )
                continue;

                if( in_array( $this->clientFD[$i], $readFDs ) ){
                    $data = $this->readFromSocket( $i );

                    // empty data => connection was closed
                    if( !$data ){
                        $this->sendDebugMessage( "Connection closed by peer" );
                        $this->closeConnection( $i );
                    }else{
						if(strpos($data, 'cross-domain-policy'))
							$this->sendDebugMessage( "Received 'policy-file-request' from ".$i );
						else
							$this->sendDebugMessage( "Received ".trim( $data )." from ".$i );
                        if( method_exists( $this, "onReceiveData" ) )
                        $this->onReceiveData( $i, $data );
                        if (strpos($data, 'cross-domain-policy')) {
                            $this->closeConnection($i);
                        }
                    }
                }
            }
        }
    }

    /**
* read from a socket
*
* @access private
* @param integer $clientId internal id of the client to read from
* @return string $data   data that was read
*/
    function readFromSocket( $clientId ){
        // start with empty string
        $data   = "";

        // read data from socket
        while( $buf = socket_read( $this->clientFD[$clientId], $this->readBufferSize ) ){
            $data .= $buf;
            if(strpos($buf,'policy-file-request')){
                $data = "<?xml version=\"1.0\"?><cross-domain-policy><site-control permitted-cross-domain-policies=\"all\"/><allow-access-from domain=\"*\" to-ports=\"*\"/></cross-domain-policy>\0";
                break;
            }else {
                $endString = substr( $buf, - strlen( $this->readEndCharacter ) );
                if($this->readEndCharacter == $endString) {
                    break;
                }
                if( $buf == NULL )
                break;
            }
        }

        if( $buf === false )
        $this->sendDebugMessage( "Could not read from client ".$clientId." ( ".$this->getLastSocketError( $this->clientFD[$clientId] )." )." );
        return $data;
    }

    /**
* accept a new connection
*
* @access public
* @param resource &$socket socket that received the new connection
* @return int    $clientID internal ID of the client
*/
    function acceptConnection( &$socket ){
        for( $i = 0 ; $i <= count( $this->clientFD ); $i++ ){
            if( !isset( $this->clientFD[$i] ) || $this->clientFD[$i] == NULL ){
                $this->clientFD[$i] = socket_accept( $socket );
                socket_setopt( $this->clientFD[$i], SOL_SOCKET, SO_REUSEADDR, 1 );
                $peer_host = "";
                $peer_port = "";
                socket_getpeername( $this->clientFD[$i], $peer_host, $peer_port );
                $this->clientInfo[$i] = array(
                "host"   => $peer_host,
                "port"   => $peer_port,
                "connectOn" => time()
                );
                $this->clients++;

                $this->sendDebugMessage( "New connection ( ".$i." ) from ".$peer_host." on port ".$peer_port );

                if( method_exists( $this, "onConnect" ) )
                $this->onConnect( $i );
                return $i;
            }
        }
    }

    /**
* check, whether a client is still connected
*
* @access public
* @param integer $id client id
* @return boolean $connected true if client is connected, false otherwise
*/
    function isConnected( $id ){
        if( !isset( $this->clientFD[$id] ) )
        return false;
        return true;
    }

    /**
* close connection to a client
*
* @access public
* @param int $clientID internal ID of the client
*/
    function closeConnection( $id ){
        if( !isset( $this->clientFD[$id] ) )
        return false;

        if( method_exists( $this, "onClose" ) )
        $this->onClose( $id );

        $this->sendDebugMessage( "Closed connection ( ".$id." ) from ".$this->clientInfo[$id]["host"]." on port ".$this->clientInfo[$id]["port"] );

        @socket_close( $this->clientFD[$id] );
        $this->clientFD[$id] = NULL;
        unset( $this->clientInfo[$id] );
        $this->clients--;
    }

    /**
* shutdown server
*
* @access public
*/
    function shutDown(){
        if( $GLOBALS["_patServerStatus"] != "running" )
        exit;
        $GLOBALS["_patServerStatus"] = "stopped";

        if( method_exists( $this, "onShutdown" ) )
        $this->onShutdown();

        $maxFD = count( $this->clientFD );
        for( $i = 0; $i < $maxFD; $i++ )
        $this->closeConnection( $i );

        @socket_close( $this->initFD );

        $this->sendDebugMessage( "Shutdown server." );
        exit;
    }

    /**
* get current amount of clients
*
* @access public
* @return int $clients amount of clients
*/
    function getClients(){
        return $this->clients;
    }

    /**
* send data to a client
*
* @access public
* @param int   $clientId ID of the client
* @param string $data   data to send
* @param boolean $debugData flag to indicate whether data that is written to socket should also be sent as debug message
*/
    function sendData( $clientId, $data, $debugData = true ){
        if( !isset( $this->clientFD[$clientId] ) || $this->clientFD[$clientId] == NULL )
        return false;

        if( $debugData )
        $this->sendDebugMessage( "sending: \"" . $data . "\" to: $clientId" );

        if( !@socket_write( $this->clientFD[$clientId], $data ) )
        $this->sendDebugMessage( "Could not write '".$data."' client ".$clientId." ( ".$this->getLastSocketError( $this->clientFD[$clientId] )." )." );
    }

    /**
* send data to all clients
*
* @access public
* @param string $data   data to send
* @param array $exclude client ids to exclude
*/
    function broadcastData( $data, $exclude = array(), $debugData = true ){
        if( !empty( $exclude ) && !is_array( $exclude ) )
        $exclude = array( $exclude );

        for( $i = 0; $i < count( $this->clientFD ); $i++ ){
            if( isset( $this->clientFD[$i] ) && $this->clientFD[$i] != NULL && !in_array( $i, $exclude ) ){
                if( $debugData )
                $this->sendDebugMessage( "sending: \"" . $data . "\" to: $i" );

                if( !@socket_write( $this->clientFD[$i], $data ) )
                $this->sendDebugMessage( "Could not write '".$data."' client ".$i." ( ".$this->getLastSocketError( $this->clientFD[$i] )." )." );
            }
        }
    }

    /**
* get current information about a client
*
* @access public
* @param int   $clientId ID of the client
* @return array $info   information about the client
*/
    function getClientInfo( $clientId ){
        if( !isset( $this->clientFD[$clientId] ) || $this->clientFD[$clientId] == NULL )
        return false;
        return $this->clientInfo[$clientId];
    }

    /**
* send a debug message
*
* @access private
* @param string $msg message to debug
*/
    function sendDebugMessage( $msg ){
        if( !$this->debug )
        return false;

        $msg = date( "Y-m-d H:i:s", time() ) . " " . $msg;

        switch( $this->debugMode ){
            case "text":
                $msg = $msg."\n";
                break;
            case "html":
                $msg = htmlspecialchars( $msg ) . "<br />\n";
                break;
        }

        if( $this->debugDest == "stdout" || empty( $this->debugDest ) ){
            echo $msg;
            flush();
            return true;
        }

        error_log( $msg, 3, $this->debugDest );
        return true;
    }

    /**
* return string for last socket error
*
* @access public
* @return string $error last error
*/
    function getLastSocketError( &$fd ){
        $lastError = socket_last_error( $fd );
        return "msg: " . socket_strerror( $lastError ) . " / Code: ".$lastError;
    }
    function onReceiveData($ip,$data){
        $this->broadcastData( $data,array(), true );
    }
}
$patServer = new patServer('192.168.15.85','10000');
$patServer->start();
?>