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Delphi DLL

Create CMS (PKCS7) Detached MIME Signature

Demonstrates how to add a CMS detached signature to MIME.

Chilkat Delphi DLL Downloads

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
mime: HCkMime;
cert: HCkCert;

begin
success := False;

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

mime := CkMime_Create();

// Load a certificate w/ private key for signing.
cert := CkCert_Create();
success := CkCert_LoadPfxFile(cert,'qa_data/pfx/ecc256_12345.p12','12345');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(cert));
    Exit;
  end;

Memo1.Lines.Add('Cert: ' + CkCert__subjectDN(cert));

// Create a simple MIME message to be signed:
CkMime_AddHeaderField(mime,'Subject','This is a test');
CkMime_AddHeaderField(mime,'MyCustomHeader','abc123');
CkMime_putContentType(mime,'text/plain');
CkMime_SetBody(mime,'This is a plain-text body.');

// Examine the MIME prior to signing:
Memo1.Lines.Add('--- MIME prior to signing ---');
Memo1.Lines.Add(CkMime__getMime(mime));

// The MIME prior to signing looks like this:

// Subject: This is a test
// MyCustomHeader: abc123
// Content-Type: text/plain; format=flowed
// 
// This is a plain-text body.

// Use SHA256 as the hash algorithm in the CMS signature.
CkMime_putSigningHashAlg(mime,'SHA256');

// Add a detached signature:
success := CkMime_AddDetachedSignature(mime,cert);
if (success = False) then
  begin
    Memo1.Lines.Add(CkMime__lastErrorText(mime));
    Exit;
  end;

// Examine the MIME with detached signature:
Memo1.Lines.Add('--- MIME with detached signature ---');
Memo1.Lines.Add(CkMime__getMime(mime));

// Content-Type: multipart/signed; boundary="----=_NextPart_6e3_c655_9641494d.b4f00501";
//  protocol="application/x-pkcs7-signature";
//  micalg=sha256
// 
// ------=_NextPart_6e3_c655_9641494d.b4f00501
// Subject: This is a test
// MyCustomHeader: abc123
// Content-Type: text/plain; format=flowed
// 
// This is a plain-text body.
// ------=_NextPart_6e3_c655_9641494d.b4f00501
// Content-Transfer-Encoding: base64
// Content-Type: application/x-pkcs7-signature; name="smime.p7s"
// Content-Disposition: attachment; filename="smime.p7s"
// 
// MIID7AYJKoZIhvcNAQcCoIID3TCCA9kCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg
// ggJxMIICbTCCAhOgAwIBAgIJAJuS2kgOoyr+MAkGByqGSM49BAEwWzELMAkGA1UEBhMCQVUxEzAR
// BgNVBAgTClNvbWUtU3RhdGUxITAfBgNVBAoTGEludGVybmV0IFdpZGdpdHMgUHR5IEx0ZDEUMBIG
// A1UEAxMLZWNjMjU2LXRlc3QwHhcNMTYwODIzMTU0OTM5WhcNNDQwMTA4MTU0OTM5WjBbMQswCQYD
// VQQGEwJBVTETMBEGA1UECBMKU29tZS1TdGF0ZTEhMB8GA1UEChMYSW50ZXJuZXQgV2lkZ2l0cyBQ
// dHkgTHRkMRQwEgYDVQQDEwtlY2MyNTYtdGVzdDBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABARy
// Hd86A7+qQ4DlIfKynZaFGdGLpkU3GlQwqaVD6GIJg3QIDhaWEksYtZ9OWjNHn9a6+i/P9o5/NrdI
// SP0VWDWjgcAwgb0wHQYDVR0OBBYEFGmd2DfK4c3VBTVn8ebKH2BTmRicMIGNBgNVHSMEgYUwgYKA
// FGmd2DfK4c3VBTVn8ebKH2BTmRicoV+kXTBbMQswCQYDVQQGEwJBVTETMBEGA1UECBMKU29tZS1T
// dGF0ZTEhMB8GA1UEChMYSW50ZXJuZXQgV2lkZ2l0cyBQdHkgTHRkMRQwEgYDVQQDEwtlY2MyNTYt
// dGVzdIIJAJuS2kgOoyr+MAwGA1UdEwQFMAMBAf8wCQYHKoZIzj0EAQNJADBGAiEAhuiwGy0lZKtK
// LA13Ffc8AMTK7NsePPSfs0clXlZUR78CIQDXsJXpYsJ7tlTeockrK+6099sG/gGFTRPiQYU8juyf
// LzGCAT8wggE7AgEBMGgwWzELMAkGA1UEBhMCQVUxEzARBgNVBAgTClNvbWUtU3RhdGUxITAfBgNV
// BAoTGEludGVybmV0IFdpZGdpdHMgUHR5IEx0ZDEUMBIGA1UEAxMLZWNjMjU2LXRlc3QCCQCbktpI
// DqMq/jANBglghkgBZQMEAgEFAKBpMBgGCSqGSIb3DQEJAzELBgkqhkiG9w0BBwEwHAYJKoZIhvcN
// AQkFMQ8XDTIyMDUwODE0MzM1NFowLwYJKoZIhvcNAQkEMSIEIMvNpYuymLvF68aFFe+l3NEQTdkB
// 7T8U6/j+Y5FgDlIUMAoGCCqGSM49BAMCBEYwRAIgQ6migEn3Le9ciIVUP/qc2JZAJZWjpulJXY9Q
// IZJ3XK0CIGZwpLOgiv7ES8958hqT9a/q7aPc1xmkaZHtsat/k+Ki
// 
// ------=_NextPart_6e3_c655_9641494d.b4f00501--

CkMime_Dispose(mime);
CkCert_Dispose(cert);

end;