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Pascal (Lazarus/Delphi)

SFTP Authenticate with Password and Private Key

See more SFTP Examples

Demonstrates the Chilkat SFtp.AuthenticatePwPk method, which authenticates with a server that requires both a password and a private key. The arguments are the username, the password, and an SshKey private key.

Note: The private-key path is relative to the application's current working directory. Supply the path to your own key file.

Background: Most servers require either a password or a public key, not both — but some high-security deployments mandate two-factor SSH, combining something you know (the password) with something you have (the key). This method satisfies that policy in one call. As always, the password should come from a secure source rather than a literal in code.

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.SFtp,
  Chilkat.SshKey;

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

procedure RunDemo;
var
  success: Boolean;
  sftp: TSFtp;
  port: Integer;
  password: string;
  privKey: TSshKey;
  keyText: string;

begin
  success := False;

  //  Demonstrates the SFtp.AuthenticatePwPk method, which authenticates with a server that requires
  //  BOTH a password and a private key.  The 1st argument is the username, the 2nd is the password,
  //  and the 3rd is an SshKey private key.

  sftp := TSFtp.Create;

  //  Step 1: Connect the SSH transport.  Port 22 is the usual port.
  port := 22;
  success := sftp.Connect('sftp.example.com',port);
  if (success = False) then
    begin
      WriteLn(sftp.LastErrorText);
      Exit;
    end;

  //  Normally you would not hard-code the password in source.  You should instead obtain it
  //  from an interactive prompt, environment variable, or a secrets vault.
  password := 'mySshPassword';

  //  Load the SSH private key.  LoadText reads the file's text, which is then imported.
  privKey := TSshKey.Create;
  keyText := privKey.LoadText('qa_data/id_rsa');
  if (privKey.LastMethodSuccess = False) then
    begin
      WriteLn(privKey.LastErrorText);
      Exit;
    end;
  success := privKey.FromOpenSshPrivateKey(keyText);
  if (success = False) then
    begin
      WriteLn(privKey.LastErrorText);
      Exit;
    end;

  success := sftp.AuthenticatePwPk('mySshLogin',password,privKey);
  if (success = False) then
    begin
      WriteLn(sftp.LastErrorText);
      Exit;
    end;

  //  Step 3: Open the SFTP subsystem.  This must be done after authentication and before any
  //  file or directory operations.
  success := sftp.InitializeSftp();
  if (success = False) then
    begin
      WriteLn(sftp.LastErrorText);
      Exit;
    end;

  WriteLn('Authenticated with a password and a private key.');

  sftp.Disconnect();


  sftp.Free;
  privKey.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.