(Delphi DLL) Create PKCS7 Signed File (.p7m)

Demonstrates how to sign a file to create a .p7m that contains both the file contents and the signature.

Note: This example requires Chilkat v10.1.2 or greater.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
crypt: HCkCrypt2;
certStore: HCkCertStore;
success: Boolean;
jsonCN: HCkJsonObject;
cert: HCkCert;
inFile: PWideChar;
outFile: PWideChar;

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

crypt := CkCrypt2_Create();

certStore := CkCertStore_Create();

// Load a PFX file into a certificate store object.
success := CkCertStore_LoadPfxFile(certStore,'myPfx.pfx','pfxPassword');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCertStore__lastErrorText(certStore));
    Exit;
  end;

// Get the certificate by subject common name.
// This should be the cert within the PFX that also
// has a private key (also stored within the PFX).
jsonCN := CkJsonObject_Create();
CkJsonObject_UpdateString(jsonCN,'CN','myCert');
cert := CkCert_Create();
success := CkCertStore_FindCert(certStore,jsonCN,cert);
if (success = False) then
  begin
    Memo1.Lines.Add(CkCertStore__lastErrorText(certStore));
    Exit;
  end;

// Tell the crypt object to use the certificate for signing:
success := CkCrypt2_SetSigningCert(crypt,cert);

// Sign a file, producing a .p7m as output.
// The input file is unchanged, the test.p7m contains the 
// contents of the input file and the signature.
inFile := 'test.txt';
outFile := 'testp7m';
success := CkCrypt2_CreateP7M(crypt,inFile,outFile);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

Memo1.Lines.Add('Success!');

CkCrypt2_Dispose(crypt);
CkCertStore_Dispose(certStore);
CkJsonObject_Dispose(jsonCN);
CkCert_Dispose(cert);

end;