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Pascal (Lazarus/Delphi)

Generate DSA SSH Key

See more SSH Key Examples

Generates a DSA SSH key and saves to various public and private key file formats (OpenSSH and PuTTY).

Chilkat Pascal (Lazarus/Delphi) Downloads

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;

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

procedure RunDemo;
var
  success: Boolean;
  key: TSshKey;
  numBits: Integer;
  exportedKey: string;
  exportEncrypted: Boolean;

begin
  success := False;

  key := TSshKey.Create;

  //  numBits should be a minimum of 1024 and
  //  a multiple of 64.  Typical values are
  //  1024 or 2048. 
  numBits := 2048;
  success := key.GenerateDsaKey(numBits);
  if (success <> True) then
    begin
      WriteLn('Invalid numBits passed to DSA key generation method.');
      Exit;
    end;

  //  Note: Generating a public/private key pair is CPU intensive
  //  and may take a short amount of time (more than few seconds,
  //  but less than a minute).

  //  Export the DSA private key to OpenSSH, PuTTY, and XML and save. 
  exportEncrypted := False;
  exportedKey := key.ToOpenSshPrivateKey(exportEncrypted);
  //  Chilkat provides a SaveText method for convenience...
  success := key.SaveText(exportedKey,'privkey_openssh_unencrypted.pem');

  //  Export with encryption to OpenSSH private key format:
  key.Password := 'secret';
  exportEncrypted := True;
  exportedKey := key.ToOpenSshPrivateKey(exportEncrypted);
  success := key.SaveText(exportedKey,'privkey_openssh_encrypted.pem');

  //  Export the DSA private key to unencrypted PuTTY format:
  exportEncrypted := False;
  exportedKey := key.ToPuttyPrivateKey(exportEncrypted);
  success := key.SaveText(exportedKey,'privkey_putty_unencrypted.ppk');

  //  Export the DSA private key to encrypted PuTTY format:
  key.Password := 'secret';
  exportEncrypted := True;
  exportedKey := key.ToPuttyPrivateKey(exportEncrypted);
  success := key.SaveText(exportedKey,'privkey_putty_encrypted.ppk');

  //  Export private key to XML:
  exportedKey := key.ToXml();
  success := key.SaveText(exportedKey,'privkey.xml');

  //  ----------------------------------------------------
  //  Now for the public key....
  //  ----------------------------------------------------

  //  The Secure Shell (SSH) Public Key File Format
  //  is documented in RFC 4716.
  exportedKey := key.ToRfc4716PublicKey();
  success := key.SaveText(exportedKey,'pubkey_rfc4716.pub');

  //  OpenSSH has a separate public-key file format, which 
  //  is also supported by Chilkat SshKey:
  exportedKey := key.ToOpenSshPublicKey();
  success := key.SaveText(exportedKey,'pubkey_openSsh.pub');

  WriteLn('Finished.');


  key.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.