Delphi DLL

Create PEM-encoded PKCS#7 Detached Signature

See more Digital Signatures Examples

Demonstrates how to create a PKCS7 PEM-encoded object containing a detached signature. Delphi DLL

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
cert: HCkCert;
crypt: HCkCrypt2;
textToSign: PWideChar;
sigBase64: PWideChar;
sb: HCkStringBuilder;
crlf: Boolean;

begin
success := False;

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

cert := CkCert_Create();

// Load the cert and private key.
success := CkCert_LoadPfxFile(cert,'qa_data/pfx/myCertAndKey.p12','password');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(cert));
    Exit;
  end;

crypt := CkCrypt2_Create();

success := CkCrypt2_SetSigningCert(crypt,cert);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

// Use SHA-256
CkCrypt2_putHashAlgorithm(crypt,'sha256');

// Hash the utf-8 byte representation of the string
CkCrypt2_putCharset(crypt,'utf-8');

// Return the result in base64
CkCrypt2_putEncodingMode(crypt,'base64Mime');

// Sign some text to create a detached signature (i.e. a signature that does not include the signed data)
textToSign := 'This is the text to be hashed and signed.';
sigBase64 := CkCrypt2__signStringENC(crypt,textToSign);
if (CkCrypt2_getLastMethodSuccess(crypt) <> True) then
  begin
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

Memo1.Lines.Add(sigBase64);

// The result:

// MIIWbgYJKoZIhvcNAQcCoIIWXzCCFlsCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg
// ghMXMIIFuzCCA6OgAwIBAgIIVwoRl0LE48wwDQYJKoZIhvcNAQELBQAwazELMAkGA1UEBhMCSVQx
// ...
// ...

// If we want it in PEM format with just LF line-endings:
sb := CkStringBuilder_Create();
// Just LF line endings, not CRLF.
crlf := False;
CkStringBuilder_AppendLine(sb,'-----BEGIN PKCS7-----',crlf);
CkStringBuilder_Append(sb,sigBase64);
CkStringBuilder_AppendLine(sb,'-----END PKCS7-----',crlf);
CkStringBuilder_ToLF(sb);

// Save to a file.
CkStringBuilder_WriteFile(sb,'c:/temp/qa_output/sig.pem','utf-8',False);

// Examine..
Memo1.Lines.Add(CkStringBuilder__getAsString(sb));

// Result is:

// -----BEGIN PKCS7-----
// MIIWbgYJKoZIhvcNAQcCoIIWXzCCFlsCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg
// ghMXMIIFuzCCA6OgAwIBAgIIVwoRl0LE48wwDQYJKoZIhvcNAQELBQAwazELMAkGA1UEBhMCSVQx
// DjAMBgNVBAcMBU1pbGFuMSMwIQYDVQQKDBpBY3RhbGlzIFMucC5BLi8wMzM1ODUyMDk2NzEnMCUG
// A1UEAwweQWN0YWxpcyBBdXRoZW50aWNhdGlvbiBSb290IENBMB4XDTExMDkyMjExMjIwMloXDTMw
// MDkyMjExMjIwMlowazELMAkGA1UEBhMCSVQxDjAMBgNVBAcMBU1pbGFuMSMwIQYDVQQKDBpBY3Rh
// bGlzIFMucC5BLi8wMzM1ODUyMDk2NzEnMCUGA1UEAwweQWN0YWxpcyBBdXRoZW50aWNhdGlvbiBS
// b290IENBMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEAp8bEpSmkLO/lGMWwUKNvUTuf
// ClrJwkg4CsIcoBh/kbWHuUA/3R1oHwiD1S0eiKD4j1aPbZkCkpAW1V8IbInX4ay8IMKx4INRimlN
// AJZaby/ARH6jDuSRzVju3PvHHkVH3Se5CAGfpiEd9UEtL0z9KK3giq0itFZljoZUj5NDKd45Rnij
// MCO6zfB9E1fAXdKDa0hMxKufgFpbOr3JpyI/gCczWw63igxdBzcIy2zSekciRDXFzMwujt0q7bd9
// ...
// ...
// -----END PKCS7-----

CkCert_Dispose(cert);
CkCrypt2_Dispose(crypt);
CkStringBuilder_Dispose(sb);

end;