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Delphi ActiveX

Convert PuTTY Private Key (ppk) to OpenSSH (pem)

See more SSH Key Examples

Convert a PuTTY format private key file (.ppk) to OpenSSH (.pem).

Chilkat Delphi ActiveX Downloads

Delphi ActiveX
uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Integer;
key: TChilkatSshKey;
keyStr: WideString;
unencryptedKeyStr: WideString;
bEncrypt: Integer;
encryptedKeyStr: WideString;

begin
success := 0;

key := TChilkatSshKey.Create(Self);

// Load an unencrypted or encrypted PuTTY private key.

// If  your PuTTY private key is encrypted, set the Password
// property before calling FromPuttyPrivateKey.
// If your PuTTY private key is not encrypted, it makes no diffference
// if Password is set or not set.
key.Password := 'secret';

// First load the .ppk file into a string:

keyStr := key.LoadText('putty_private_key.ppk');

// Import into the SSH key object:
success := key.FromPuttyPrivateKey(keyStr);
if (success <> 1) then
  begin
    Memo1.Lines.Add(key.LastErrorText);
    Exit;
  end;

// Convert to an encrypted or unencrypted OpenSSH key.

// First demonstrate converting to an unencrypted OpenSSH key

bEncrypt := 0;
unencryptedKeyStr := key.ToOpenSshPrivateKey(bEncrypt);
success := key.SaveText(unencryptedKeyStr,'unencrypted_openssh.pem');
if (success <> 1) then
  begin
    Memo1.Lines.Add(key.LastErrorText);
    Exit;
  end;

// Save to an encrypted OpenSSH PEM file:

bEncrypt := 1;
key.Password := 'myPassword';
encryptedKeyStr := key.ToOpenSshPrivateKey(bEncrypt);
success := key.SaveText(encryptedKeyStr,'encrypted_openssh.pem');
if (success <> 1) then
  begin
    Memo1.Lines.Add(key.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('Done!');
end;