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Delphi DLL

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.

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Delphi DLL
uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Cert, Crypt2;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
crypt: HCkCrypt2;
cert: HCkCert;
toBeEncrypted: PWideChar;
result: PWideChar;

begin
success := False;

crypt := CkCrypt2_Create();

// Specify the encryption to be used.
// "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped-data) message.
CkCrypt2_putCryptAlgorithm(crypt,'pki');
CkCrypt2_putPkcs7CryptAlg(crypt,'aes');
CkCrypt2_putKeyLength(crypt,256);
CkCrypt2_putOaepHash(crypt,'sha256');
CkCrypt2_putOaepPadding(crypt,True);

cert := CkCert_Create();

// Use a certificate found in the Windows certificate store.
success := CkCert_LoadByCommonName(cert,'My Certificate');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(cert));
    Exit;
  end;

// Tell the crypt object to use the certificate.
CkCrypt2_SetEncryptCert(crypt,cert);

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

// Get the result in multi-line BASE64 MIME format.
CkCrypt2_putEncodingMode(crypt,'base64_mime');
CkCrypt2_putCharset(crypt,'utf-8');

result := CkCrypt2__encryptStringENC(crypt,toBeEncrypted);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

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

Memo1.Lines.Add(result);

// 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=

CkCrypt2_Dispose(crypt);
CkCert_Dispose(cert);

end;