Delphi DLL Requires Chilkat v11.0.0+

RSASSA-PSS Sign Text

Signs text to create a PKCS7/CMS signature. The signature algorithm is RSASSA-PSS with SHA256. Delphi DLL

var
success: Boolean;
crypt: HCkCrypt2;
pfx: HCkPfx;
cert: HCkCert;
sb: HCkStringBuilder;
i: Integer;
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');

//  Build a string to sign
sb := CkStringBuilder_Create();
i := 1;
while i < 12 do
  begin
    CkStringBuilder_AppendInt(sb,i);
    CkStringBuilder_Append(sb,' the quick brown fox jumped over the lazy dog.' + #13#10);
    i := i + 1;
  end;

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

//  The string to be encrypted looks like this:

//  1 the quick brown fox jumped over the lazy dog.
//  2 the quick brown fox jumped over the lazy dog.
//  3 the quick brown fox jumped over the lazy dog.
//  4 the quick brown fox jumped over the lazy dog.
//  ...

//  Make sure to specify the byte representation (character encoding)
CkCrypt2_putCharset(crypt,'utf-8');

//  Sign the string to get a PKCS7 detached signature in base64 format.
pkcs7sig := CkCrypt2__signSbENC(crypt,sb);
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
//  MQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTcwNDI5MTYzNTQ3WjAvBgkqhkiG9w0BCQQx
//  IgQgnXqtpfBjs9ZZUJxbNYbwYvpmXTGgIbYErkIA3jQo0EEwXwYJKoZIhvcNAQkPMVIwUDALBglg
//  hkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFAMAcGBSsO
//  AwIHMA0GCCqGSIb3DQMCAgEoMIGxBgkrBgEEAYI3EAQxgaMwgaAwgZIxCzAJBgNVBAYTAkFVMREw
//  DwYDVQQIDAhWaWN0b3JpYTESMBAGA1UEBwwJTWVsYm91cm5lMSEwHwYDVQQKDBhJbnRlcm5ldCBX
//  aWRnaXRzIFB0eSBMdGQxDzANBgNVBAMMBldpZGdldDEoMCYGCSqGSIb3DQEJARYZYWRtaW5AaW50
//  ZXJuZXR3aWRnZXRzLmNvbQIJAMPsJCT11cniMIGzBgsqhkiG9w0BCRACCzGBo6CBoDCBkjELMAkG
//  A1UEBhMCQVUxETAPBgNVBAgMCFZpY3RvcmlhMRIwEAYDVQQHDAlNZWxib3VybmUxITAfBgNVBAoM
//  GEludGVybmV0IFdpZGdpdHMgUHR5IEx0ZDEPMA0GA1UEAwwGV2lkZ2V0MSgwJgYJKoZIhvcNAQkB
//  FhlhZG1pbkBpbnRlcm5ldHdpZGdldHMuY29tAgkAw+wkJPXVyeIwPQYJKoZIhvcNAQEKMDCgDTAL
//  BglghkgBZQMEAgGhGjAYBgkqhkiG9w0BAQgwCwYJYIZIAWUDBAIBogMCASAEgYBFgBS1vtBoac6P
//  /NRcY3jdytoxK7xc8vEYW/PhgsbE+sP7dvu6eoRLVicoQ8RIeMh3CtPZFq1+JcL5NNzQoAotizTX
//  EKhiceX1mC5ocCeEvgNouxkN2Qr/X12m60rNvNl5r+GEqiqx/1fs2yRAl5sIzwPsMMY3p9tGOpy0
//  5p7sRQ==

//  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_VerifySbENC(crypt,sb,pkcs7sig);
Memo1.Lines.Add('Signature verified: ' + IntToStr(Ord(success)));

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