I tryed to create a socket in php and reuse it from other process.
I know this can be done with a daemon script but I want to do this without.
I created a socket and binded it to a specific port.
$sock = socket_create (AF_INET, SOCK_STREAM, SOL_TCP);
socket_set_option ($sock, SOL_SOCKET, SO_REUSEADDR, 1);
socket_bind ($sock, 'xx.xx.xx.xx', 10000);
socket_connect ($sock, $host, $port);
And from another php file I did the same thing. But the packets that I send from the 2 file are not "validated" by host. I sniffed all ports and I see that it uses same local and destination port. I don't understand where is the problem.
Can you help me with this?
It's ok in any other programming language, or any other solution for this.
Andrew
Sockets are not symmetrical. The server side listens on a specific port for a client to conect - the client does not specify the local port - only the remote port and address. Its nothing to do with the language you implement it in.
There's a very good socket server implementation available at http://www.phpclasses.org/browse/package/5758.html with examples.
C.
You can't really use persistent sockets in php. When you execute a php file, a new process is created which cannot access the variables - or sockets - of a different php process so it won't know if there already exists a socket and just creates it.
Related
I have a function which creates a socket connection and listens on a port number for HL7 messages sent by a laboratory machine via TCP.
If the lab machine is not sending anything, my listen function keeps listening. Is there a way to specify that it should listen only for say 10 seconds and then if there are no messages, an error should be thrown?
$address = '0.0.0.0';
$port = 5600;
// Create a TCP Stream socket
$sock = socket_create(AF_INET, SOCK_STREAM, 0);
// Bind the socket to an address/port
$bind = socket_bind($sock, $address, $port);
// Start listening for connections
socket_listen($sock);
$client = socket_accept($sock);
// Read the input from the client
$input = socket_read($client, 2024);
// Strip all white spaces from input
$segs = explode("|",$input);
// Close the master sockets
$close = socket_close($sock);
This is the solution:
socket_set_option($sock,SOL_SOCKET,SO_RCVTIMEO,array("sec"=>10,"usec"=>0)); // after 10 seconds socket will destroy the connection. Also you can set and uses
This looks like the XY problem.
That the thing you want to measure acts as a client rather implies that you might want to do more than just detect an open TCP connection in your script, e.g. capture some data. Further, the underlying OS has a lot of complex, well tested, reliable and tunable mechanisms for tracking the state of connections.
While you could do as stefo91 suggests and try to manipulate receive timeout, I'm not sure if this is applied in the wait for an initial connection. A better solution would be to set the socket to non-blocking. Don't forget to either:
inject some calls to sleep()/usleep() or
use socket_select()
unless you want your script to be burning a lot of resource with nothing to do.
But depending on a lot of information you've not told us about, the right solution might be to run one script as a server, and a second as a monitor. The second could be polling/parsing the output of netstat to check the connection.
I'm trying to understand how we can use Php socket to let our client send messages to our Node.js server using TLS...
My problem is that i don't know how that is done in Php. Can someone please show me how that can be done in php and explain the steps please???
I have tried to search on many website to gain understanding about it. To connect to TCP server in Php we can do such:
// IPv4
$sock = #socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
// IPv6
$sock = #socket_create(AF_INET6, SOCK_STREAM, SOL_TCP);
$sock->connect($address);
// now we can send to the server using socket_write
How can the same be done with TLS instead of TCP in PHP???
I'm not looking for help with the Node.js server, just php..
I have written some code in PHP to create a socket and listen for incoming connections. I am trying to do this using a specific port I'm interested in.
Everything is going well, except it opens the listening TCP socket on some random port, instead of the one chosen by me.
I'm running this code on Google Compute Engine (GCE).
Here is the exact php code that I tried:
set_time_limit(0);
$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_set_option($socket, SOL_SOCKET, SO_REUSEADDR, 1);
$address = '35.190.179.17';
//bind socket to specified host
socket_bind($socket, $address,54468);
//listen to port
socket_listen($socket);
I got the issue resolved by using the internal IP instead of external IP address and opening the port for external connections.
Compute engine was not allowing socket bind using external IP address.
I've got a Python server which multiple clients connect to using sockets. At the moment one server isn't able to cope with the load so I'm looking at ways to split the clients up according to some criteria such as their username.
The intention is to put clients with usernames starting with A-G on server 1, H-P on server 2 and P-Z on server 3.
What I'm trying to do is to write a process that will listen for connections on port 45000 and will then forward those on to the appropriate server on 45001, 45002 and 45003.
At the moment, when a client connects to the original server they connect via a TCP port e.g. 45000. The server checks that they are authorised and responds on a random port with a handshake e.g. 59117, 60647 or 61573.
The response port is not specified when the client first connects so my question is, when is the value determined and how does the client know to listen on that port for the reply ?
So far I've written a PHP process which takes the data from the clients and forwards it to the appropriate server but I can't work out which port to listen on for the response back from the server. Is there some way that PHP sockets can negotiate the response port so that it can be stored in a variable in my script ?
Here's my basic connection code in PHP. I have no knowledge of Python so this is going to have to be done in PHP:
// Define remote Server
$socket=socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
// Open socket on remote server to send $buf data to
socket_connect($socket, 'X.X.X.X', 40149);
echo ("Forwarding data ($buf) to $socket ....\r\n");
$bytesWritten=socket_write($socket, $buf, strlen($buf));
echo ("Wrote: $bytesWritten bytes\r\n");
// Now listen for response but this will be on another socket
// How do we know what this is ?
if (false === ($response = socket_read($socket, 16384))) {
echo ("Response: $response\r\n");
}
This is way out of my comfort zone so I may have this completely wrong but an afternoon spent Googling has turned up any answers yet.
I intend to design a web gps tracking application. the gps transmits data using TCP (no HTTP headers) on port 7070 (which I intented to change to 80). I know the protocol for communication between the GPS tracker and client, however i am stuck as i cannot intercept the datapacket on webserver.
Since application is in development stage and me being a hobbyist, I cannot afford a dedicated web host server and thus get access to php-cli interface for socket programming.
is there any way i can circumvent the need for php-cli and intercept the raw tcp packet.
Thanks
Simply have a dedicated PHP script listening on port 7070, which you can accomplish with fsockopen(). You don't want to have your GPS sending directly to port 80 when Apache's already listening on port 80. Apache'll see a non-HTTP set of data come in and ignore the request completely.
$handle = fsockopen('localhost', 7070, $errno, $errstr);
if (!$handle) {
die("Couldn't bind to socket (err $errno): $errstr");
}
while($data = fgets($handle)) {
... process gps data ...
}
would be the very simplest basic form of this.