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Delphi DLL

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

See more SSH Key Examples

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

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
key: HCkSshKey;
keyStr: PWideChar;
unencryptedKeyStr: PWideChar;
bEncrypt: Boolean;
encryptedKeyStr: PWideChar;

begin
success := False;

key := CkSshKey_Create();

// 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.
CkSshKey_putPassword(key,'secret');

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

keyStr := CkSshKey__loadText(key,'putty_private_key.ppk');

// Import into the SSH key object:
success := CkSshKey_FromPuttyPrivateKey(key,keyStr);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSshKey__lastErrorText(key));
    Exit;
  end;

// Convert to an encrypted or unencrypted OpenSSH key.

// First demonstrate converting to an unencrypted OpenSSH key

bEncrypt := False;
unencryptedKeyStr := CkSshKey__toOpenSshPrivateKey(key,bEncrypt);
success := CkSshKey_SaveText(key,unencryptedKeyStr,'unencrypted_openssh.pem');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSshKey__lastErrorText(key));
    Exit;
  end;

// Save to an encrypted OpenSSH PEM file:

bEncrypt := True;
CkSshKey_putPassword(key,'myPassword');
encryptedKeyStr := CkSshKey__toOpenSshPrivateKey(key,bEncrypt);
success := CkSshKey_SaveText(key,encryptedKeyStr,'encrypted_openssh.pem');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSshKey__lastErrorText(key));
    Exit;
  end;

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

CkSshKey_Dispose(key);

end;