(PHP ActiveX) Create PKCS7 (CMS) EnvelopedData

Encrypt some data to a recipient by creating a PKCS7 (CMS) EnvelopedData structure. The data will be encrypted using a symmetric content-encryption algorithm (e.g., AES), and the randomly generated symmetric key will be encrypted using the recipient’s RSA public key extracted from their X.509 certificate.

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

$crypt = new COM("Chilkat.Crypt2");

// Specify the encryption to be used.
// "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped-data) message.
$crypt->CryptAlgorithm = 'pki';
$crypt->Pkcs7CryptAlg = 'aes';
$crypt->KeyLength = 256;
$crypt->OaepHash = 'sha256';
$crypt->OaepPadding = 1;

$cert = new COM("Chilkat.Cert");

// Use a certificate found in the Windows certificate store.
$success = $cert->LoadByCommonName('My Certificate');
if ($success != 1) {
    print $cert->LastErrorText . "\n";
    exit;
}

// Tell the crypt object to use the certificate.
$crypt->SetEncryptCert($cert);

$toBeEncrypted = 'This string is to be encrypted.';

// Get the result in multi-line BASE64 MIME format.
$crypt->EncodingMode = 'base64_mime';
$crypt->Charset = 'utf-8';

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

// -------------------------------------------------------------------------
// See the following example to decrypt what was created in this example
// Decrypt PKCS7 (CMS) EnvelopedData
// -------------------------------------------------------------------------

print $result . "\n";

// Sample output:

// MIICSgYJKoZIhvcNAQcDoIICOzCCAjcCAQAxggHiMIIB3gIBADCBljCBgTELMAkGA1UEBhMCSVQx
// EDAOBgNVBAgMB0JlcmdhbW8xGTAXBgNVBAcMEFBvbnRlIFNhbiBQaWV0cm8xFzAVBgNVBAoMDkFj
// dGFsaXMgUy5wLkEuMSwwKgYDVQQDDCNBY3RhbGlzIENsaWVudCBBdXRoZW50aWNhdGlvbiBDQSBH
// MwIQPCWvkSv8oQ7xRmEHJ6TzEDA8BgkqhkiG9w0BAQcwL6APMA0GCWCGSAFlAwQCAQUAoRwwGgYJ
// KoZIhvcNAQEIMA0GCWCGSAFlAwQCAQUABIIBAKqHAPQNSsQoX7B2NH7QyEOWQRsSVs8oCHXmy8f4
// MVZD2er3bvYUCIomxpwbLEAl14qjUIMynahooYGgqip7+4FqL301G+BVjZVfEhHWj+VI1dAWnWuL
// VHlvc/pbQNBWqV8rKVJsNIsuAZkdj4WSwLVKxYkYX43B8fh/g71XN2DTJu7Z/824v48KBmgpQBOT
// 2q7IcDGxNPAFN2p6eavIVGn2LvhEbf/Fszyj+GR5tMcnQP1BOLJ3s3JzUBbvj8hcZrF1Vhl9HnTU
// YQx8G/KdW1mR+Wlhl3BWoK0LYKRTbnTx2BXOs0CY1SXOAdhKr01ZYjA+xW4nGzY0lfXS9QZjh9gw
// TAYJKoZIhvcNAQcBMB0GCWCGSAFlAwQBKgQQw0xTbfmnt0zjWHo5SaQIp4AgxTVY9E/Ncqy6t+RM
// 8y4c3Av62/wB8IpPUEmtM2OeuZo=

?>