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Delphi DLL

SFTP Public-Key Authentication

See more SFTP Examples

Demonstrates how to authenticate with an SSH/SFTP server using publickey 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;
hostname: PWideChar;
port: Integer;
key: HCkSshKey;
privKey: PWideChar;

begin
success := False;

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

sftp := CkSFtp_Create();

// Set some timeouts, in milliseconds:
CkSFtp_putConnectTimeoutMs(sftp,5000);
CkSFtp_putIdleTimeoutMs(sftp,15000);

// Connect to the SSH server.  
// The standard SSH port = 22
// The hostname may be a hostname or IP address.
hostname := 'sftp.example.com';
port := 22;
success := CkSFtp_Connect(sftp,hostname,port);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSFtp__lastErrorText(sftp));
    Exit;
  end;

key := CkSshKey_Create();

// Load a PEM file into a string variable:
// (This does not load the PEM file into the key.  The LoadText
// method is a convenience method for loading the full contents of ANY text
// file into a string variable.)
privKey := CkSshKey__loadText(key,'myPrivateKey.pem');
if (CkSshKey_getLastMethodSuccess(key) <> True) then
  begin
    Memo1.Lines.Add(CkSshKey__lastErrorText(key));
    Exit;
  end;

// Load a private key from a PEM string:
// (Private keys may be loaded from OpenSSH and Putty formats.
// Both encrypted and unencrypted private key file formats
// are supported.  This example loads an unencrypted private
// key in OpenSSH format.
success := CkSshKey_FromOpenSshPrivateKey(key,privKey);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSshKey__lastErrorText(key));
    Exit;
  end;

// Authenticate with the SSH server.  Chilkat SFTP supports
// both password-based authenication as well as public-key
// authentication.  
success := CkSFtp_AuthenticatePk(sftp,'myLogin',key);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSFtp__lastErrorText(sftp));
    Exit;
  end;
Memo1.Lines.Add(CkSFtp__lastErrorText(sftp));
Memo1.Lines.Add('Public-Key Authentication Successful!');

CkSFtp_Dispose(sftp);
CkSshKey_Dispose(key);

end;