[SOLVED] need linux script to listen to port 12111 read request verify it and reply

maaking · 01-28-2012, 11:20 AM

Hello there,

I need to create linux bash script to listen to port eg. 12111 read user request verify it then reply one line of data.

the user will send this: userid|mobile_imei|symbid

then should take userid and search in database

PHP Code:



$sql = mysql_query("select * from users where u_id=userid"); 
if(mysql_numrows($sql) == 1){ 
//if the user is in database then 
//grab data from table 
$row = mysql_fetach_array($sql); 
 
reply with the following 
 
{1}{$row[mobile_activation_number]} 
 
}

I did this on my machine:

Code:

Code:

nc -l 12111

the port was open okay . and i received the request. BUT i cannot do anything more.

any help will be appreciated .

regards

Nominal Animal · 01-28-2012, 02:11 PM

You seem to know PHP, so why not use the CLI (command-line-interface) PHP for this? Here is a skeleton to get you fully started:

PHP Code:



#!/usr/bin/php5
<?PHP

if (count($argv) != 3) {
    fprintf(STDERR, "Usage: %s address port\n", $argv[0]);
    exit(1);
}

$socket = @socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
if ($socket === FALSE) {
    fprintf(STDERR, "Cannot create an IPv4 TCP socket.\n");
    exit(1);
}

if (@socket_bind($socket, $argv[1], intval($argv[2])) === FALSE) {
    fprintf(STDERR, "Cannot bind to %s port %d: %s.\n",
                    $argv[1], intval($argv[2]),
                    socket_strerror(socket_last_error()));
    exit(1);
}

if (@socket_listen($socket) === FALSE) {
    fprintf(STDERR, "Cannot listen %s port %d: %s.\n",
                    $argv[1], intval($argv[2]),
                    socket_strerror(socket_last_error()));
    exit(1);
}

fprintf(STDERR, "Waiting for incoming connections.\n");
fflush(STDERR);

/* Single-threaded incoming service loop. */
while (($connection = @socket_accept($socket)) !== FALSE) {

    /* Find out who the other end is. */
    $client_address = "";
    $client_port = 0;
    if (@socket_getpeername($connection, $client_address, $client_port) === TRUE) {

        /* Show the connection information. */
        fprintf(STDERR, "Connection from %s port %d:\n",
                        $client_address, $client_port);
        fflush(STDERR);

        /* Read the request, accepting up to 256 bytes only. */
        $request = "";
        $length = @socket_recv($connection, $request, 256, 0);

        /* Filter out all unwanted characters. Simpler than escaping. */
        $request = preg_replace('/[^-._\/0-9@A-Z_a-z|]/', "", $request);

        /* Split the request into components. */
        list($user, $mobile, $sym, $ignore) = explode('|', $request . "|||", 4);

        /* Check the request. */
        if ((strlen($user)   > 0 && strlen($user)   < 64) &&
            (strlen($mobile) > 0 && strlen($mobile) < 32) &&
            (strlen($sym)    > 0 && strlen($sym)    < 32)) {

            /* Okay, looks like a valid request. */
            fprintf(STDERR, "\tRequest for user '%s', mobile '%s', sym '%s'.\n",
                            $user, $mobile, $sym);
            fflush(STDERR);

            /* Process the request.
             * This example just returns the SHA1 hash of the request fields,
             * as text, with a newline appended.
            */
            $response = sha1($user . "|" . $mobile . "|" . $sym, FALSE) . "\n";

            /* Send the response. Includes end-of-connection mark. */
            $response_length = strlen($response);
            $response_sent   = 0;
            while ($response_sent < $response_length) {
                $bytes = socket_send($connection,
                                     substr($response, $response_sent),
                                     $response_length - $response_sent,
                                     MSG_EOF);
                if ($bytes > 0)
                    $response_sent += $bytes;
                else
                    break;
            }
            if ($response_sent == $response_length)
                fprintf(STDERR, "\tResponse sent successfully.\n");
            else
                fprintf(STDERR, "\tError sending response: %s.\n",
                                socket_strerror(socket_last_error($connection)));

        } else
            fprintf(STDERR, "\tInvalid request '%s'.\n", $request);

    } else
        fprintf(STDERR, "Incoming connection was aborted.\n");

    /* Tell the client we are fully done, and close the connection. */
    @socket_shutdown($connection, 2);
    @socket_close($connection);

    fprintf(STDERR, "\tConnection closed.\n");
    fflush(STDERR);
}

/* Report the cause of the malfunction. */
fprintf(STDERR, "Cannot accept connection: %s.\n",
                socket_strerror(socket_last_error()));

/* Close socket, making sure no connections are left to linger. */
@socket_set_option($socket, SOL_SOCKET, SO_LINGER, array(0, 0));
@socket_set_option($socket, SOL_SOCKET, SO_KEEPALIVE, 0);
@socket_set_option($socket, SOL_SOCKET, SO_REUSEADDR, 1);
@socket_close($socket);

exit(0);
?>

Save it as ./myserver, allow it to be executed (chmod u=rwx,g=rx ./myserver), and run it specifying both the address and port, e.g.

Code:

./myserver 127.0.0.1 50000

Then you can see what it returns by using e.g.

Code:

echo "foo|bar|baz" | nc 127.0.0.1 50000

There is nothing PHP-y in the connection. It is exactly the same as you'd get by using Python or Ruby or Perl or C++ or C on the server side. The resource use is not that different, either, but if you find you want something more powerful, then you can switch languages without any effect on the clients.

maaking · 02-07-2012, 11:09 AM

hello Nominal Animal

your code has worked fine with me. I am very happy for it.

I am unable to thank you for this. you have saved my live.

much much much appreciated.

regards