Sending emails from PHPMailer using proxies IP addresses

Question

I need to send emails from PHPMailer using proxies IP addresses, I know that to do so, I need to use the fsockopen function so I can connect to the SMTP account, I also know that if I have to connect to the proxy I have to use the fsockopen function again. But using it fsockopen inside another fsockopen is not doable.

I have transparent proxy and require no authentication. I need to send this to a distant SMTP server of an external Email Service Provider.

The code I have tried :

<?php

    //SMTP params
    $server      = 'smtp.espdomain.com';
    $server_port = '25';
    $username = 'smtp_login';
    $password = 'smtp_pass';

    //Proxy
    $proxy      = '1.1.1.1';
    $proxy_port = 1111;

    //Open connection
    $socket = fsockopen($proxy, $proxy_port);

    //Send command to proxy
    fputs($socket, "CONNECT $server:$server_port HTTP/1.0\r\nHost: $proxy\r\n\r\n");
    fgets($socket, 334);

    //SMTP authorization  
    fputs($socket, "AUTH LOGIN\r\n");
    fgets($socket, 334);

    fputs($socket, base64_encode($username)."\r\n");
    fgets($socket, 334);

    fputs($socket, base64_encode($password)."\r\n");
    $output = fgets($socket, 235);

    fputs($socket, "HELO $server \r\n"); 
    $output = fgets($socket, 515);

?>

And it's not working I'm not sure why?

Could socat commands help in this situation or is there any solution or alternative solution to achieve that?

Answer 1

I finally found the solution using socat, Kindly follow these steps :

1. First of all, you'll need to install socat on the server, you can do that simply using the command below :

   yum install socat
   

2. Then run the following socat command that will bind PROXY_IP:PORT with HOST_ESP:PORT :

   socat TCP4-LISTEN:proxy_port,bind=proxy_IP,fork,su=nobody TCP4:host:port,bind=proxy_IP
   

3. Then instead of making a send to the ESP through HOST_ESP:PORT you could just make it using PROXY_IP:PORT and socat will do the redirection automatically towards HOST_ESP:PORT using the output of PROXY_IP:PORT.

Hope this helps.