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Delphi DLL

Use PuTTY Key for SFTP Authentication

See more SFTP Examples

Demonstrates how to authenticate with a username + .ppk PuTTY private key for SFTP authentication.

Chilkat Delphi DLL Downloads

Delphi DLL
uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, SFtp, SshKey;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
sftp: HCkSFtp;
puttyKey: HCkSshKey;
ppkText: PWideChar;
sshHostname: PWideChar;
sshPort: Integer;

begin
success := False;

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

sftp := CkSFtp_Create();

// Load a .ppk PuTTY private key.
puttyKey := CkSshKey_Create();
ppkText := CkSshKey__loadText(puttyKey,'qa_data/ppk/putty_private_secret.ppk');

// The ppkText contains this content:

// 	PuTTY-User-Key-File-2: ssh-rsa
// 	Encryption: aes256-cbc
// 	Comment: rsa-key-20170126
// 	Public-Lines: 6
// 	AAAAB3NzaC1yc2EAAAABJQAAAQEAx+52s7vvaZ8rT2UdFZWlSUVDHDQ+5ZRFvgRW
// 	6nm2sO1c9WqNg7u2PQL4jeKSDX2XWcMnpleALz2x8Rr4rMy5E1iZzvWov8VtFd8l
// 	fa9HOkgEeJB3VFuYR3NlnD3eyCoYJYPVpHJHrIeui2WZs5vQ76HDe+th8+z5Ald4
// 	zPw3p2c6ZJpBrkSBM67hWokoBDi23c7NhszDHhJBrv+B98cQxnagI1PUKqN7E8Vg
// 	bNtBI8beIMHyI69up9G1AXSEi0cGIjYNx9RNUPau1mRk/SvfqxgWkAjM005lj7hc
// 	bOsjbdKK3T2NtrKTaYjEiXlEXcj1iGuApsD/m73pYaEJB3Nd7w==
// 	Private-Lines: 14
// 	MoaDbq0owouN/7Z9Pga0favDhM2bSEgMErJBxdDmNUXIVVcUoLiD/Ps1RA+BeBBX
// 	wxqKUt9PqLy/pnafPR/i2xjJiQtQ0CWkPxND16Gi1dqLzmbQYYl1ev4+LzuG0zNX
// 	HDGMvRiwagY7mY+F1tUjBYfOL6z8XHw4m40YcY1QorOO+0MMzAVT5Hkg8YyXW209
// 	B/V/LRADFMVA2BlL39y11cb5ZpFStPH/waYUMY+2w1ZmJZ7dcRoMjuKmY+YE/tUx
// 	n9X3P0qTNSbw6e6sMG3Dhr1vfoJUQWApUliD6GpUiCeIvXBcVqG8Vsfq9XADsPl0
// 	+nFAwjSZflywcB7/FwhGb7q5UmcJK06SzoMl7Og5e3g7NCs3yNNQIv+qCpDjhxrA
// 	hpT03mbipu7OXCZDeUwUhMGJAmYHE5iqm1rPCsSVbaMgpxhCWf01Cx4gLx3aMvn4
// 	MdylA31GuL3wSxcWTslrOI8+449lZN/qZEnGEZkYTrnlu123jTqsAWMMtuHSz2Ig
// 	6GA89oTdlppkNflhNH3OJ85kMUrc3p/ZBMdndz8jTDTljmJjHR5oNMoShFof115A
// 	nWjUHqBwCgcubLYyH3afDvBTOhtl0tJ9Oby0wJlOAGnCXiPSDbF/y7J7xml/PS9t
// 	XlSVNxtAY15NDO6Fp96sBVfKuJsfJ90PzdBom4ikIuf7sMwtElrHHLuYfcXJQYLp
// 	G5jBmqDgnirosVPEBIxlxFzz/HCRmdU+tsYg46gqI4R5UpKUe8WSaJoZkDGsrqhm
// 	e+1SJaBuafR4v2bx/bV414Hg7LGQosK2S3crxH4UgZl+g02vWznZfBH+9CmHvKDR
// 	AxfcKOTzsaILKJtQPV81lmJ45sARYMcB5jMiE4kBg56hiXouChsvKkm55WVcW1E+
// 	Private-MAC: 17512c9f7582c1d9c3ae2b01b4d67a6b1dbd1d0e

// "secret" is the actual password for the above PPK.
CkSshKey_putPassword(puttyKey,'secret');
success := CkSshKey_FromPuttyPrivateKey(puttyKey,ppkText);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSshKey__lastErrorText(puttyKey));
    Exit;
  end;

sshHostname := 'sftp.example.com';
sshPort := 22;

// Connect to an SSH/SFTP server
success := CkSFtp_Connect(sftp,sshHostname,sshPort);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSFtp__lastErrorText(sftp));
    Exit;
  end;

// Authenticate with the SSH server using a username + private key.
// (The private key serves as the password.  The username identifies
// the SSH user account on the server.)
success := CkSFtp_AuthenticatePk(sftp,'mySshLogin',puttyKey);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSFtp__lastErrorText(sftp));
    Exit;
  end;

Memo1.Lines.Add('OK, the connection and authentication with the SSH server is completed.');

// This example is only to show the connection + authentication using a PuTTY private key...

CkSFtp_Dispose(sftp);
CkSshKey_Dispose(puttyKey);

end;