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Socket-Funktionen

<<socket_close

socket_create_listen>>

socket_connect

(PHP 4 >= 4.1.0, PHP 5)

socket_connectBaut eine Verbindung über einen Socket auf

Beschreibung

bool socket_connect ( resource $socket , string $address [, int $port = 0 ] )

Baut über den gültigen Socket-Deskriptor socket, der von socket_create() zurückgegeben wurde, eine Verbindung zu address auf.

Parameter-Liste

socket

address

Der Parameter address ist entweder eine IPv4-Adresse in Punktnotation (z.B. 127.0.0.1), falls socket zur AF_INET-Familie gehört, oder eine gültige IPv6-Adresse (z.B ::1), falls die IPv6-Unterstützung aktiviert ist und socket zur AF_INET6-Familie gehört, oder der Pfadname eines Unix-Domain socket, falls der Socket zur AF_UNIX-Familie gehört.

port

Der Parameter port wird nur benutzt und ist dann zwingend erforderlich, wenn eine Verbindung zu einem AF_INET- oder einem AF_INET6-Socket aufgebaut wird. Er gibt an, zu welchem Port des entfernten Hosts eine Verbindung hergestellt werden soll.

Rückgabewerte

Gibt bei Erfolg TRUE zurück. Im Fehlerfall wird FALSE zurückgegeben. Der Fehlercode kann mit der Funktion socket_last_error() ermittelt werden. Dieser Fehlercode kann an die Funktion socket_strerror() übergeben werden, um eine textuelle Beschreibung des Fehlers zu erhalten.

Hinweis:

Falls der Socket nicht blockiert ist, gibt diese Funktion FALSE sowie die Fehlermeldung Operation now in progress zurück.

Siehe auch


13 BenutzerBeiträge:
- Beiträge aktualisieren...
peter at videoripper dot org
29.10.2009 20:29
This will give you a simple port-checker.

Note that on production-machines, you might want to alter the error reporting-level,
since unsuccessful connects will give you a "No connection could be made because
the target machine actively refused it"-error in the log.

Under Windows, make sure you enable the php_sockets.dll extension in your php.ini.

<?php 
  $address
=$_SERVER['REMOTE_ADDR'];
 
  if (isset(
$_REQUEST['port']) and
      (!
strlen($_REQUEST['port'])==0))
   
$port=$_REQUEST['port'];
  else
    unset(
$port);
   
  if (isset(
$port) and
      (
$socket=socket_create(AF_INET, SOCK_STREAM, SOL_TCP)) and
      (
socket_connect($socket, $address, $port)))
    {
     
$text="Connection successful on IP $address, port $port";
     
socket_close($socket);
    }
  else
   
$text="Unable to connect<pre>".socket_strerror(socket_last_error())."</pre>";
   
  echo
"<html><head></head><body>".
      
$text.
      
"</body></html>";
?>

Greetz,

Peter.
jerrywilborn at gmail dot com
2.09.2009 18:40
This will print the banner from a true 'telnet' server (router, switch, host, etc).

$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_connect($socket, '127.0.0.1', 23);

while (TRUE) {
        $r = array($socket);
        $c = socket_select($r, $w = NULL, $e = NULL, 5);

        foreach ($r as $read_socket) {
                if ($r = negotiate($read_socket)) {
                        var_dump($r);
                        exit;
                }
        }
}

function negotiate ($socket) {
        socket_recv($socket, $buffer, 1024, 0);

        for ($chr = 0; $chr < strlen($buffer); $chr++) {
                if ($buffer[$chr] == chr(255)) {

                        $send = (isset($send) ? $send . $buffer[$chr] : $buffer[$chr]);

                        $chr++;
                        if (in_array($buffer[$chr], array(chr(251), chr(252)))) $send .= chr(254);
                        if (in_array($buffer[$chr], array(chr(253), chr(254)))) $send .= chr(252);

                        $chr++;
                        $send .= $buffer[$chr];
                } else {
                        break;
                }
        }

        if (isset($send)) socket_send($socket, $send, strlen($send), 0);
        if ($chr - 1 < strlen($buffer)) return substr($buffer, $chr);

}
vshih at yahoo
14.04.2009 21:52
rbarnes' tip is helpful, but I found that I needed to add a check for SOCKET_EISCONN in the while loop:

    ...
    $error = socket_last_error();

    if ($error == SOCKET_EISCONN) {
        $connected = true;
        break;
    }
    ...

At least on Mac OS X 10.5.
maganap
18.09.2008 9:15
Hi there!

For the TCP connections: socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
In case you're having problems in socket_connect() with socket_strerror() = "Permission denied", you may be having a SELinux config issue.

Check if SELinux is enabled:
# /usr/sbin/sestatus -v
In case it is, you can just type the command:
# setsebool httpd_can_network_connect=1

That's it... I read you had to reboot, but I didn't and it worked fine anyway. More info, you may check:
http://arkiv.netbsd.se/?ml=squirrelmail-users&a=2005-11&t=1523021
rbarnes at fake dot com
15.07.2008 19:04
Here is an example of a non-blocking connect which should perform quite a bit faster than the one posted by Seymour below:

<?php
function msConnectSocket($remote, $port, $timeout = 30) {
       
# this works whether $remote is a hostname or IP
       
$ip = "";
        if( !
preg_match('/^\d+\.\d+\.\d+\.\d+$/', $remote) ) {
           
$ip = gethostbyname($remote);
            if (
$ip == $remote) {
               
$this->errstr = "Error Connecting Socket: Unknown host";
                return
NULL;
            }
        } else
$ip = $remote;

        if (!(
$this->_SOCK = @socket_create(AF_INET, SOCK_STREAM, SOL_TCP))) {
           
$this->errstr = "Error Creating Socket: ".socket_strerror(socket_last_error());
            return
NULL;
        }

       
socket_set_nonblock($this->_SOCK);

       
$error = NULL;
       
$attempts = 0;
       
$timeout *= 1000// adjust because we sleeping in 1 millisecond increments
       
$connected;
        while (!(
$connected = @socket_connect($this->_SOCK, $remote, $port+0)) && $attempts++ < $timeout) {
           
$error = socket_last_error();
            if (
$error != SOCKET_EINPROGRESS && $error != SOCKET_EALREADY) {
               
$this->errstr = "Error Connecting Socket: ".socket_strerror($error);
               
socket_close($this->_SOCK);
                return
NULL;
            }
           
usleep(1000);
        }

        if (!
$connected) {
           
$this->errstr = "Error Connecting Socket: Connect Timed Out After $timeout seconds. ".socket_strerror(socket_last_error());
           
socket_close($this->_SOCK);
            return
NULL;
        }
       
       
socket_set_block($this->_SOCK);

        return
1;     
}
?>
mike at fserve dot us
22.02.2008 23:14
This probably sounds like common sense, but it is something nobody i asked thought of... you can't bind the socket to localhost, you must bind it to either the IP your router assigns you, or your public IP address. If you bind to localhost, it will give an invalid resource error.
ScriptBlue at nyc dot rr dot com
17.09.2005 18:13
If you do want to have a socket_connect operation timeout you can use the following code.
<?php
$sock
= socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_set_nonblock($sock);
socket_connect($sock,"127.0.0.1", 80);
socket_set_block($sock);
switch(
socket_select($r = array($sock), $w = array($sock), $f = array($sock), 5))
{
        case
2:
                echo
"[-] Connection Refused\n";
                break;
        case
1:
                echo
"[+] Connected\n";
                break;
        case
0:
                echo
"[-] Timeout\n";
                break;
}
?>
This basically makes socket_connect return immediately then you can use socket_select to see how the socket reacted.
telefoontoestel at home
23.11.2003 9:05
In reply to the function socket_raw_connect posted by "net_del at freemail dot ru". In the function you give a return value and afterwords you try to close the connection. That won't ever work. I think you want to alter your code ;-)
seymour@itsyourdomain
1.10.2003 21:43
here's how you can implement timeouts with the socket functions.

this example works for blocking sockets but will work for both blocking and nonblocking with minor modifications. first call to connect in nonblocking mode returns 115 EINPROGRESS, additional calls return 114 EALREADY if the connection has not already failed or succeeded. once the connection succeeds, the socket resource will be returned.

<?
    $host
= "127.0.0.1";
   
$port = "80";
   
$timeout = 15//timeout in seconds

   
$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP)
      or die(
"Unable to create socket\n");

   
socket_set_nonblock($socket)
      or die(
"Unable to set nonblock on socket\n");

   
$time = time();
    while (!@
socket_connect($socket, $host, $port))
    {
     
$err = socket_last_error($socket);
      if (
$err == 115 || $err == 114)
      {
        if ((
time() - $time) >= $timeout)
        {
         
socket_close($socket);
          die(
"Connection timed out.\n");
        }
       
sleep(1);
        continue;
      }
      die(
socket_strerror($err) . "\n");
    }

   
socket_set_block($this->socket)
      or die(
"Unable to set block on socket\n");
?>
net_del at freemail dot ru
26.08.2003 22:54
function socket_raw_connect ($server, $port, $timeout,$request)
{
 if (!is_numeric($port) or !is_numeric($timeout)) {return false;}
 $socket = fsockopen($server, $port, $errno, $errstr, $timeout);
 fputs($socket, $request);
 $ret = '';
 while (!feof($socket))
 {
  $ret .= fgets($socket, 4096);
 }
 return $ret;
 fclose($socket);
}

this code for easy raw connect.

Comment by net_del[nkg] (www.nkg.ru)
I am from russia. PHP is good language!
w at ff dot st
28.06.2003 11:20
man page for connect :
 EINPROGRESS
The socket is non-blocking and the connection cannot be completed immediately.  It is possible to select(2) or poll(2) for completion by selecting the socket for writing. After select indicates  writability,  use  getsockopt(2)  to read the SO_ERROR option at level SOL_SOCKET to determine whether connect completed successfully (SO_ERROR is zero) or unsuccessfully (SO_ERROR is one of the usual error codes listed here, explaining the reason for the failure).

use socket_getoption($socket,SOL_SOCKET,SO_ERROR) . If you get value 115, it is connecting. If you get value different than 115 and 0, that means that an error has occured (see what error with socket_strerror()).

However, I don't know how does that works under Windows, maybe it wont work at all. It is supposed to work under Linux (man pages said that).
greg at mtechsolutions dot ca
30.04.2003 23:12
If you're using non-blocking, be sure not to turn it on until after you connect, otherwise you will get the mesasge:

PHP Warning:  socket_connect() unable to connect [115]: Operation now in progress in file.php on line 123

and socket_connect() will return false (even though it will connect).
logan at voerthegame dot com
24.07.2002 20:24
I had the same problem with the timeout, and i applied this solution.

It works only on linux PHP, i make a ping to the ip before connect the socket.....

<?php
$address
= gethostbyname ($ip);
       
$command = "ping -c 1 " . $address
       
$r = exec($command); 
          if (
$r[0]=="r")
          {       
           
$socket = socket_create (AF_INET, SOCK_STREAM, 0);
            if (
$socket < 0) {
                echo
"socket_create() failed: reason: " . socket_strerror ($socket) . "\n";
            } else {
                echo
"OK.\n";
            }
?>



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