(PHP ActiveX) Encrypt File using X.509 Certificate using AES in CBC Mode

Demonstrates how to encrypt a file using an X.509 Certificate's public key, where the underlying bulk encryption algorithm is 128-bit AES in CBC mode. (The underlying bulk encryption algorithm can be specified to be other algorithms/strengths.)

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows Note: The php_com_dotnet.dll may need to be enabled inside of php.ini.

<?php

// This example requires the Chilkat Crypt API to have been previously unlocked.
// See Unlock Chilkat Crypt for sample code.

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Crypt2')
$crypt = new COM("Chilkat.Crypt2");

// Use public-key cryptography for encryption.
$crypt->CryptAlgorithm = 'pki';

// Get an X.509 certificate to use for encrypting.
// Note: Chilkat provides many different ways of loading a certificate, from many different formats,
// or if on Windows, from the installed certificates on the system.
// This example simply loads a certificate from a file.
// Also, for encryption, only the public key is needed.  Digital certificates embed the public key
// within the X.509 format itself.  Therefore, if you have a certificate, you also have the public key.
// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Cert')
$cert = new COM("Chilkat.Cert");
$success = $cert->LoadFromFile('qa_data/certs/testCert.cer');
if ($success != 1) {
    print $cert->LastErrorText . "\n";
    exit;
}

$success = $crypt->SetEncryptCert($cert);
if ($success != 1) {
    print $crypt->LastErrorText . "\n";
    exit;
}

// Indicate the underlying bulk encryption algorithm to be used:
$crypt->Pkcs7CryptAlg = 'aes';
$crypt->KeyLength = 128;

// Note: When doing public-key encryption the underlying bulk symmetric cipher mode will always be CBC. (at least with Chilkat...)

// There's one last option that could be set.  If is the RSA encryption encryption/padding scheme. 
// By default, RSAES_PKCS1-V1_5 is used.  If desired, the OaepPadding property could be set to 1 to
// use RSAES_OAEP.  (We'll leave it set at the default value of 0)
$crypt->OaepPadding = 0;

// Everything is specified.  Now just encrypt...
// The output is PKCS7 in binary DER format.
$success = $crypt->CkEncryptFile('qa_data/hamlet.xml','qa_output/hamlet.p7');
if ($success != 1) {
    print $crypt->LastErrorText . "\n";
    exit;
}

print 'Finished.' . "\n";

?>