(PHP Extension) FTP Connect, Examine Server Certificate, and then Authenticate

Demonstrates how to connect to an FTP server, examine the server's SSL/TLS certificate, and then, if it meets the application's security requirements, proceed to authenticate.

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux, Solaris

<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

// This example assumes Chilkat Ftp2 to have been previously unlocked.
// See Unlock Ftp2 for sample code.

$ftp = new CkFtp2();

$ftp->put_Hostname('www.authtls-ftps-server.com');
$ftp->put_Username('FTP_LOGIN');
$ftp->put_Password('FTP_PASSWORD');
$ftp->put_AuthTls(true);
$ftp->put_Port(21);

// Connect to the FTP server using explicit TLS (AUTH TLS).
$success = $ftp->ConnectOnly();
if ($success != true) {
    print $ftp->lastErrorText() . "\n";
    exit;
}

// Get the FTP server's certificate.
// serverCert is a CkCert
$serverCert = $ftp->GetSslServerCert();
if ($ftp->get_LastMethodSuccess() != true) {
    print $ftp->lastErrorText() . "\n";
    exit;
}

// Now that we have the certificate, we can check it in any way we desire.
// (See the online reference documentation for the certificate object's methods
// and properties)...

// Assuming the certificate is OK, proceed to authenticate with the FTP server.
$success = $ftp->LoginAfterConnectOnly();
if ($success != true) {
    print $ftp->lastErrorText() . "\n";
    exit;
}

// 
// Proceed with uploading/download files, etc...
// 

$ftp->Disconnect();
print 'Success.' . "\n";

?>