Using Gmails Outgoing SMTP from PHP using TLS

Question

I'm sending email from PHP through the Gmail SMTP server. I've been using the CakePHP email component with SMTP settings set. I originally had it all working fine using SSL over port 465 but have found my web host doesn't allow outgoing traffic over 465. They did however tell me that outgoing connections over port 587 is allowed.

After reading http://mail.google.com/support/bin/answer.py?answer=13287 I thought it would be as easy as changing the port number and protocol but I can't get it to work.

The offending line of code seems to be a fsockopen call:

fsockopen("ssl://smtp.gmail.com", 465, $errNum, $errStr, 30); // WORKS
fsockopen("tls://smtp.gmail.com", 587, $errNum, $errStr, 30); // FAILS

The errors given are:

Warning: fsockopen(): SSL operation failed with code 1. OpenSSL Error messages:
error:1408F10B:SSL routines:SSL3_GET_RECORD:wrong version number in Command line code on line 1

Warning: fsockopen(): Failed to enable crypto in Command line code on line 1

Warning: fsockopen(): unable to connect to tls://smtp.gmail.com:587 (Unknown error) in Command line code on line 1

This is with PHP 5.3, phpinfo shows OpenSSL is enabled. Any help would be greatly appreciated.

Answer 1

Not sure if you are still looking for it, but to start tls, you have to do it from the commands with the server. Here is a simple set up that works for tls with gmail (if you want more help beyond just connecting via tls, start another question):

<?php
function get($socket,$length=1024){
    $send = '';
    $sr = fgets($socket,$length);
    while( $sr ){
        $send .= $sr;
        if( $sr[3] != '-' ){ break; }
        $sr = fgets($socket,$length);
    }
    return $send;
}
function put($socket,$cmd,$length=1024){
    fputs($socket,$cmd."\r\n",$length);
}
if (!($smtp = fsockopen("smtp.gmail.com", 587, $errno, $errstr, 15))) {
    die("Unable to connect");
}
echo "<pre>\n";
echo get($smtp); // should return a 220 if you want to check

$cmd = "EHLO ${_SERVER['HTTP_HOST']}";
echo $cmd."\r\n";
put($smtp,$cmd);
echo get($smtp); // 250

$cmd = "STARTTLS";
echo $cmd."\r\n";
put($smtp,$cmd);
echo get($smtp); // 220
if(false == stream_socket_enable_crypto($smtp, true, STREAM_CRYPTO_METHOD_TLS_CLIENT)){
    // fclose($smtp); // unsure if you need to close as I haven't run into a security fail at this point
    die("unable to start tls encryption");
}

$cmd = "EHLO ".$_SERVER['HTTP_HOST'];
echo $cmd;
put($smtp,$cmd);
echo get($smtp); // 250

$cmd = "QUIT";
echo $cmd."\r\n";
put($smtp,$cmd);
echo get($smtp);

echo "</pre>";

fclose($smtp);

Answer 2

Why not use PEAR?

http://email.about.com/od/emailprogrammingtips/qt/PHP_Email_SMTP_Authentication.htm

Change the port in the second example.