MIME S/MIME Encryption Algorithm Properties

See more MIME Examples

Demonstrates the properties that control S/MIME encryption: Pkcs7CryptAlg (the symmetric content-encryption algorithm), Pkcs7KeyLength (the content-encryption key length in bits), OaepPadding (whether RSAES-OAEP key transport is used instead of RSAES-PKCS1-v1_5), and the OAEP hash settings OaepHash and OaepMgfHash. The properties are configured before calling Encrypt.

var
success: Boolean;
mime: HCkMime;
cert: HCkCert;

begin
success := False;

mime := CkMime_Create();
success := CkMime_SetBodyFromPlainText(mime,'This message will be encrypted.');
if (success = False) then
  begin
    Memo1.Lines.Add(CkMime__lastErrorText(mime));
    Exit;
  end;

//  Pkcs7CryptAlg is the symmetric content-encryption algorithm.  Supported values are aes, aes-gcm,
//  des, 3des, and rc2.  The default is aes.
CkMime_putPkcs7CryptAlg(mime,'aes');

//  Pkcs7KeyLength is the content-encryption key length in bits.  The default is 128.
CkMime_putPkcs7KeyLength(mime,256);

//  OaepPadding selects the RSA key-transport padding.  The default is 0 (RSAES-PKCS1-v1_5).
//  Set 1 to use RSAES-OAEP, in which case the OAEP hash settings apply.
CkMime_putOaepPadding(mime,True);
CkMime_putOaepHash(mime,'sha256');
CkMime_putOaepMgfHash(mime,'sha256');

//  Load the recipient certificate (public key is sufficient for encrypting).
cert := CkCert_Create();
success := CkCert_LoadFromFile(cert,'qa_data/recipient.cer');
if (success = False) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(cert));
    Exit;
  end;

//  Encrypt using the algorithm settings configured above.
success := CkMime_Encrypt(mime,cert);
if (success = False) then
  begin
    Memo1.Lines.Add(CkMime__lastErrorText(mime));
    Exit;
  end;

Memo1.Lines.Add('Encrypted with ' + CkMime__pkcs7CryptAlg(mime) + ' ' + IntToStr(CkMime_getPkcs7KeyLength(mime)) + '-bit key.');

CkMime_Dispose(mime);
CkCert_Dispose(cert);