Pascal (Lazarus/Delphi)

SSH Authenticate using Smart Card Private Key

See more SSH Examples

Demonstrates how to use a private key stored on an HSM (smartcard or token) for SSH public-key authentication. (Public-key authentication means the client, which is your application, uses the private key, while the corresponding public key is installed on the server under your SSH account.)

Note: This example requires Chilkat v9.5.0.96 or later.

Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.SshKey,
  Chilkat.Pkcs11,
  Chilkat.Ssh,
  Chilkat.JsonObject;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  pkcs11: TPkcs11;
  pin: string;
  userType: Integer;
  jsonTemplate: TJsonObject;
  privKeyHandle: LongWord;
  pubKeyHandle: LongWord;
  sshKey: TSshKey;
  ssh: TSsh;

begin
  success := False;

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

  //  Note: Chilkat's PKCS11 implementation runs on Windows, Linux, Mac OS X, and other supported operating systems.

  pkcs11 := TPkcs11.Create;

  //  Use the PKCS11 driver (.dll, .so, .dylib) for your particular HSM.
  //  For example:
  pkcs11.SharedLibPath := 'C:/Program Files (x86)/Gemalto/IDGo 800 PKCS#11/IDPrimePKCS11.dll';

  //  Use your HSM's PIN.
  pin := '0000';

  //  Normal user = 1
  userType := 1;

  //  Establish a logged-on user session with the HSM.
  success := pkcs11.QuickSession(userType,pin);
  if (success = False) then
    begin
      WriteLn(pkcs11.LastErrorText);
      Exit;
    end;

  //  Provide a template to find a PKCS11 object.
  jsonTemplate := TJsonObject.Create;

  //  Find an RSA private key with the label "MySshKey".
  //  Here's an example of how the key was originally imported: 
  //  PKCS11 Import SSH Key
  jsonTemplate.UpdateString('class','private_key');
  jsonTemplate.UpdateString('key_type','rsa');
  jsonTemplate.UpdateString('label','MySshKey');

  privKeyHandle := pkcs11.FindObject(jsonTemplate);
  if (privKeyHandle = 0) then
    begin
      WriteLn(pkcs11.LastErrorText);
      Exit;
    end;

  //  The private key handle is only valid during the PKCS11 session.
  //  If you wish to use the private key in another PKCS11 session,
  //  you'll first need to find it.  See:  
  WriteLn('private key handle: ' + privKeyHandle);

  //  We'll also need the PKCS11 public key handle
  //  Modify the template by updating the "class" to "public_key"
  jsonTemplate.UpdateString('class','public_key');

  pubKeyHandle := pkcs11.FindObject(jsonTemplate);
  if (pubKeyHandle = 0) then
    begin
      WriteLn(pkcs11.LastErrorText);
      Exit;
    end;

  WriteLn('public key handle: ' + pubKeyHandle);

  //  Create an empty SSH key object, and tell it to use the PKCS11 handles.
  //  We also need to indicate the key type.
  sshKey := TSshKey.Create;
  success := sshKey.UsePkcs11(pkcs11,privKeyHandle,pubKeyHandle,'rsa');
  if (success = False) then
    begin
      WriteLn(sshKey.LastErrorText);
      Exit;
    end;

  //  Create an SSH object and authenticate using the SSH key, which will utilize the existing PKCS11 session.
  ssh := TSsh.Create;

  success := ssh.Connect('my-ssh-server.com',22);
  if (success = False) then
    begin
      WriteLn(ssh.LastErrorText);
      Exit;
    end;

  //  This is where the PKCS11 private key on the smart card is used.
  success := ssh.AuthenticatePk('your_ssh_username',sshKey);
  if (success = False) then
    begin
      WriteLn(ssh.LastErrorText);
      Exit;
    end;

  //  Do whatever it is your app needs to do using the authenticated SSH session....
  //  ...
  //  ...

  ssh.Disconnect();

  pkcs11.Logout();
  pkcs11.CloseSession();


  pkcs11.Free;
  jsonTemplate.Free;
  sshKey.Free;
  ssh.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.