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Delphi DLL Requires Chilkat v11.0.0+

RSASSA-PSS Sign Binary Data

See more Digital Signatures Examples

Signs binary data to create a PKCS7/CMS signature. The signature algorithm is RSASSA-PSS with SHA256.

Chilkat Delphi DLL Downloads

Delphi DLL
var
success: Boolean;
crypt: HCkCrypt2;
pfx: HCkPfx;
cert: HCkCert;
binaryData: HCkBinData;
pkcs7sig: PWideChar;

begin
success := False;

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

crypt := CkCrypt2_Create();

//  Get a digital certificate with private key from a .pfx
//  (Chilkat has many different ways to provide a cert + private key for siging.
//  Using a PFX is just one possible option.)
pfx := CkPfx_Create();
success := CkPfx_LoadPfxFile(pfx,'qa_data/rsassa-pss/privatekey.pfx','PFX_PASSWORD');
if (success = False) then
  begin
    Memo1.Lines.Add(CkPfx__lastErrorText(pfx));
    Exit;
  end;

//  Get the certificate to be used for signing.
//  (The typical case for a PFX is that it contains a cert with an associated private key,
//  as well as other certificates in the chain of authentication.  The cert with the private
//  key should be in the first position at index 0.)

cert := CkCert_Create();
success := CkPfx_CertAt(pfx,0,cert);
if (success = False) then
  begin
    Memo1.Lines.Add(CkPfx__lastErrorText(pfx));
    Exit;
  end;

CkCrypt2_SetSigningCert(crypt,cert);

//  Indicate that RSASSA-PSS with SHA256 should be used.
CkCrypt2_putSigningAlg(crypt,'pss');
CkCrypt2_putHashAlgorithm(crypt,'sha256');

CkCrypt2_putEncodingMode(crypt,'base64_mime');

//  Load a binary file to be signed:
binaryData := CkBinData_Create();
success := CkBinData_LoadFile(binaryData,'qa_data/jpg/starfish20.jpg');
if (success <> True) then
  begin
    Memo1.Lines.Add('Failed to load file.');
    Exit;
  end;

//  Sign the binary bytes to get a PKCS7 detached signature in base64 format:
pkcs7sig := CkCrypt2__signBdENC(crypt,binaryData);
Memo1.Lines.Add('Detached PCKS7 Signature:');
Memo1.Lines.Add(pkcs7sig);

//  This signature looks like this:

//  MIIG5wYJKoZIhvcNAQcCoIIG2DCCBtQCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg
//  ggL4MIIC9DCCAl2gAwIBAgIJAMPsJCT11cniMA0GCSqGSIb3DQEBCwUAMIGSMQswCQYDVQQGEwJB
//  VTERMA8GA1UECAwIVmljdG9yaWExEjAQBgNVBAcMCU1lbGJvdXJuZTEhMB8GA1UECgwYSW50ZXJu
//  ZXQgV2lkZ2l0cyBQdHkgTHRkMQ8wDQYDVQQDDAZXaWRnZXQxKDAmBgkqhkiG9w0BCQEWGWFkbWlu
//  QGludGVybmV0d2lkZ2V0cy5jb20wHhcNMTYxMTAxMTY1MjMyWhcNMjExMDMxMTY1MjMyWjCBkjEL
//  MAkGA1UEBhMCQVUxETAPBgNVBAgMCFZpY3RvcmlhMRIwEAYDVQQHDAlNZWxib3VybmUxITAfBgNV
//  BAoMGEludGVybmV0IFdpZGdpdHMgUHR5IEx0ZDEPMA0GA1UEAwwGV2lkZ2V0MSgwJgYJKoZIhvcN
//  AQkBFhlhZG1pbkBpbnRlcm5ldHdpZGdldHMuY29tMIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKB
//  gQDGIdoCjyavs+F/Rm0VIB4m6O7VL1j+1IqieoR9NEX2GQvu2VCdceyxf9qaw1bxipEvjLwUkw7M
//  e+BTlLpWQbBMH87s6KpsC8MVyXhMLpP0oM8NFix/vLz2wdLhUh7CZvJA0plqkJk9bj57QIu+EO1k
//  tUHM2DFb6sckvCL2yybD1wIDAQABo1AwTjAdBgNVHQ4EFgQUONKKu2zsXIrinWxIGT654vrcQwsw
//  HwYDVR0jBBgwFoAUONKKu2zsXIrinWxIGT654vrcQwswDAYDVR0TBAUwAwEB/zANBgkqhkiG9w0B
//  AQsFAAOBgQArFvdi5u9i2QF1Qw+cdC1l7w2Y3+q6RIkln2W8rWJFje00644o8hXy7v46giJCedmF
//  ULlhm1n7XIsZGy2W3lJ77v5agn9gFwXu1h3cqkGXkoteE6SQJQXWgsW3GWPveObvTL8LF4y57fgM
//  9ZWS+V9MJajeu44Rf/tU17TLYKjvEjGCA7MwggOvAgEBMIGgMIGSMQswCQYDVQQGEwJBVTERMA8G
//  A1UECAwIVmljdG9yaWExEjAQBgNVBAcMCU1lbGJvdXJuZTEhMB8GA1UECgwYSW50ZXJuZXQgV2lk
//  Z2l0cyBQdHkgTHRkMQ8wDQYDVQQDDAZXaWRnZXQxKDAmBgkqhkiG9w0BCQEWGWFkbWluQGludGVy
//  bmV0d2lkZ2V0cy5jb20CCQDD7CQk9dXJ4jANBglghkgBZQMEAgEFAKCCAjQwGAYJKoZIhvcNAQkD
//  MQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTcwNDI5MTYxMDI2WjAvBgkqhkiG9w0BCQQx
//  IgQgrjUQkoMeBYUhmDGjPg147WybF0w2LAY6F+Ih6qHUMB8wXwYJKoZIhvcNAQkPMVIwUDALBglg
//  hkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFAMAcGBSsO
//  AwIHMA0GCCqGSIb3DQMCAgEoMIGxBgkrBgEEAYI3EAQxgaMwgaAwgZIxCzAJBgNVBAYTAkFVMREw
//  DwYDVQQIDAhWaWN0b3JpYTESMBAGA1UEBwwJTWVsYm91cm5lMSEwHwYDVQQKDBhJbnRlcm5ldCBX
//  aWRnaXRzIFB0eSBMdGQxDzANBgNVBAMMBldpZGdldDEoMCYGCSqGSIb3DQEJARYZYWRtaW5AaW50
//  ZXJuZXR3aWRnZXRzLmNvbQIJAMPsJCT11cniMIGzBgsqhkiG9w0BCRACCzGBo6CBoDCBkjELMAkG
//  A1UEBhMCQVUxETAPBgNVBAgMCFZpY3RvcmlhMRIwEAYDVQQHDAlNZWxib3VybmUxITAfBgNVBAoM
//  GEludGVybmV0IFdpZGdpdHMgUHR5IEx0ZDEPMA0GA1UEAwwGV2lkZ2V0MSgwJgYJKoZIhvcNAQkB
//  FhlhZG1pbkBpbnRlcm5ldHdpZGdldHMuY29tAgkAw+wkJPXVyeIwPQYJKoZIhvcNAQEKMDCgDTAL
//  BglghkgBZQMEAgGhGjAYBgkqhkiG9w0BAQgwCwYJYIZIAWUDBAIBogMCASAEgYCWV0g82volvnwf
//  YpwIpqpQzMmTPBKNQmFGjbyH2opdcbJwgu2qEFvaXkyjYDtgQ7XsCqc15dm6Ee1Ujkosbp57kLTt
//  /WbwxY1CC/uxs3oV+5ESUyB+2iocTYABYn4ye0FhBPut86n/gzZTL+RLG6Z1fxwwzkoxWUp7GjKK
//  58mveQ==

//  The ASN.1 of the signature can be examined by browsing to https://lapo.it/asn1js/ ,
//  then copy-and-paste the Base64 signature into the form and decode..

//  The signature can be verified against the original data like this:
success := CkCrypt2_VerifyBdENC(crypt,binaryData,pkcs7sig);
Memo1.Lines.Add('Signature verified: ' + IntToStr(Ord(success)));

//  Now we'll create an opaque signature (the opposite of a detached signature). 
//  An opaque signature is a PKCS7/CMS message that contains both the original data and
//  the signature.  The verification process extracts the original data.

//  Then OpaqueSignBd method in-place signs the binaryData.
//  The contents of binaryData are replaced with the CMS/PKCS7 message.
success := CkCrypt2_OpaqueSignBd(crypt,binaryData);

//  Show the contents of the opaque signature in base64 format:
Memo1.Lines.Add('Opaque Signature:');
Memo1.Lines.Add(CkBinData__getEncoded(binaryData,'base64_mime'));

//  MIIKCgYJKoZIhvcNAQcCoIIJ+zCCCfcCAQExDzANBglghkgBZQMEAgEFADCCAywGCSqGSIb3DQEH
//  AaCCAx0EggMZ/9j/4AAQSkZJRgABAQEASABIAAD//gAmRmlsZSB3cml0dGVuIGJ5IEFkb2JlIFBo
//  b3Rvc2hvcD8gNC4w/9sAQwAQCwwODAoQDg0OEhEQExgoGhgWFhgxIyUdKDozPTw5Mzg3QEhcTkBE
//  V0U3OFBtUVdfYmdoZz5NcXlwZHhcZWdj/9sAQwEREhIYFRgvGhovY0I4QmNjY2NjY2NjY2NjY2Nj
//  Y2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2Nj/8IAEQgAFAAUAwERAAIRAQMRAf/E
//  ABcAAAMBAAAAAAAAAAAAAAAAAAIDBAX/xAAYAQADAQEAAAAAAAAAAAAAAAABAgMEAP/aAAwDAQAC
//  EAMQAAAB2kZYNNEijWKddfTmLgALWH//xAAbEAACAgMBAAAAAAAAAAAAAAABAgMRAAQSE//aAAgB
//  AQABBQL0XqN+pM2aqJGMiqFFCyg7z//EABwRAAICAgMAAAAAAAAAAAAAAAERAAIQIQMSUf/aAAgB
//  AwEBPwHqU5aqAxx+y1tMQl4elj//xAAcEQEAAQUBAQAAAAAAAAAAAAABEQACEBIhA1H/2gAIAQIB
//  AT8B3Bhqy7ZcenyiwmGgDhiOzj//xAAdEAABAwUBAAAAAAAAAAAAAAABAAIREBIhIkFR/9oACAEB
//  AAY/ArZyn+CgxtxWuJaoCnqDuin/xAAcEAABBAMBAAAAAAAAAAAAAAABABEhYRAxQVH/2gAIAQEA
//  AT8hkEwPUUR9DYfE4nxtRpIkBTsayuALIiuY/9oADAMBAAIAAwAAABDWPTsf/8QAGhEAAwADAQAA
//  AAAAAAAAAAAAAAEREDFBIf/aAAgBAwEBPxC0DVPcWm+Ce4OesrkE6bjH/8QAGBEBAQEBAQAAAAAA
//  AAAAAAAAAREAQRD/2gAIAQIBAT8QahMiOc8YgSrnTY3ELclHXn//xAAcEAEBAAIDAQEAAAAAAAAA
//  AAABEQAhMUFxEFH/2gAIAQEAAT8Qn3igmSZSj+c4N4zapMy9IjFV98wncN2iuLFsCEbDGxQkI6RO
//  /n//2aCCAvgwggL0MIICXaADAgECAgkAw+wkJPXVyeIwDQYJKoZIhvcNAQELBQAwgZIxCzAJBgNV
//  BAYTAkFVMREwDwYDVQQIDAhWaWN0b3JpYTESMBAGA1UEBwwJTWVsYm91cm5lMSEwHwYDVQQKDBhJ
//  bnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQxDzANBgNVBAMMBldpZGdldDEoMCYGCSqGSIb3DQEJARYZ
//  YWRtaW5AaW50ZXJuZXR3aWRnZXRzLmNvbTAeFw0xNjExMDExNjUyMzJaFw0yMTEwMzExNjUyMzJa
//  MIGSMQswCQYDVQQGEwJBVTERMA8GA1UECAwIVmljdG9yaWExEjAQBgNVBAcMCU1lbGJvdXJuZTEh
//  MB8GA1UECgwYSW50ZXJuZXQgV2lkZ2l0cyBQdHkgTHRkMQ8wDQYDVQQDDAZXaWRnZXQxKDAmBgkq
//  hkiG9w0BCQEWGWFkbWluQGludGVybmV0d2lkZ2V0cy5jb20wgZ8wDQYJKoZIhvcNAQEBBQADgY0A
//  MIGJAoGBAMYh2gKPJq+z4X9GbRUgHibo7tUvWP7UiqJ6hH00RfYZC+7ZUJ1x7LF/2prDVvGKkS+M
//  vBSTDsx74FOUulZBsEwfzuzoqmwLwxXJeEwuk/Sgzw0WLH+8vPbB0uFSHsJm8kDSmWqQmT1uPntA
//  i74Q7WS1QczYMVvqxyS8IvbLJsPXAgMBAAGjUDBOMB0GA1UdDgQWBBQ40oq7bOxciuKdbEgZPrni
//  +txDCzAfBgNVHSMEGDAWgBQ40oq7bOxciuKdbEgZPrni+txDCzAMBgNVHRMEBTADAQH/MA0GCSqG
//  SIb3DQEBCwUAA4GBACsW92Lm72LZAXVDD5x0LWXvDZjf6rpEiSWfZbytYkWN7TTrjijyFfLu/jqC
//  IkJ52YVQuWGbWftcixkbLZbeUnvu/lqCf2AXBe7WHdyqQZeSi14TpJAlBdaCxbcZY+945u9MvwsX
//  jLnt+Az1lZL5X0wlqN67jhF/+1TXtMtgqO8SMYIDszCCA68CAQEwgaAwgZIxCzAJBgNVBAYTAkFV
//  MREwDwYDVQQIDAhWaWN0b3JpYTESMBAGA1UEBwwJTWVsYm91cm5lMSEwHwYDVQQKDBhJbnRlcm5l
//  dCBXaWRnaXRzIFB0eSBMdGQxDzANBgNVBAMMBldpZGdldDEoMCYGCSqGSIb3DQEJARYZYWRtaW5A
//  aW50ZXJuZXR3aWRnZXRzLmNvbQIJAMPsJCT11cniMA0GCWCGSAFlAwQCAQUAoIICNDAYBgkqhkiG
//  9w0BCQMxCwYJKoZIhvcNAQcBMBwGCSqGSIb3DQEJBTEPFw0xNzA0MjkxNjEwMjZaMC8GCSqGSIb3
//  DQEJBDEiBCCuNRCSgx4FhSGYMaM+DXjtbJsXTDYsBjoX4iHqodQwHzBfBgkqhkiG9w0BCQ8xUjBQ
//  MAsGCWCGSAFlAwQBAjAKBggqhkiG9w0DBzAOBggqhkiG9w0DAgICAIAwDQYIKoZIhvcNAwICAUAw
//  BwYFKw4DAgcwDQYIKoZIhvcNAwICASgwgbEGCSsGAQQBgjcQBDGBozCBoDCBkjELMAkGA1UEBhMC
//  QVUxETAPBgNVBAgMCFZpY3RvcmlhMRIwEAYDVQQHDAlNZWxib3VybmUxITAfBgNVBAoMGEludGVy
//  bmV0IFdpZGdpdHMgUHR5IEx0ZDEPMA0GA1UEAwwGV2lkZ2V0MSgwJgYJKoZIhvcNAQkBFhlhZG1p
//  bkBpbnRlcm5ldHdpZGdldHMuY29tAgkAw+wkJPXVyeIwgbMGCyqGSIb3DQEJEAILMYGjoIGgMIGS
//  MQswCQYDVQQGEwJBVTERMA8GA1UECAwIVmljdG9yaWExEjAQBgNVBAcMCU1lbGJvdXJuZTEhMB8G
//  A1UECgwYSW50ZXJuZXQgV2lkZ2l0cyBQdHkgTHRkMQ8wDQYDVQQDDAZXaWRnZXQxKDAmBgkqhkiG
//  9w0BCQEWGWFkbWluQGludGVybmV0d2lkZ2V0cy5jb20CCQDD7CQk9dXJ4jA9BgkqhkiG9w0BAQow
//  MKANMAsGCWCGSAFlAwQCAaEaMBgGCSqGSIb3DQEBCDALBglghkgBZQMEAgGiAwIBIASBgAGVtpI5
//  slxfw+1EyJK4jqxokLvUrqksBLotv1vaP4QaSeF2A1lNrsPfJoEjZJpD1F6vXrFPsR4sPD+6n7P/
//  lz3sGoFykTjE2rPwKEFIbzfxD3gSZKJPWFgDa19DojarmwJMkSPXt9TQEzdjDPrbsCGLYOy29Puq
//  ZDI1rUcyxg7Y

//  The ASN.1 of the signature can be examined by browsing to https://lapo.it/asn1js/ ,
//  then copy-and-paste the Base64 signature into the form and decode..

//  The signature is verified, and the original data restored like this:
success := CkCrypt2_OpaqueVerifyBd(crypt,binaryData);
if (success <> True) then
  begin
    Memo1.Lines.Add('Signature verification failed.');
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

//  Save the extracted data to a file:
success := CkBinData_WriteFile(binaryData,'qa_output/extractedStarfish20.jpg');

Memo1.Lines.Add('Signature verified.');

CkCrypt2_Dispose(crypt);
CkPfx_Dispose(pfx);
CkCert_Dispose(cert);
CkBinData_Dispose(binaryData);