Pascal (Lazarus/Delphi)

Get Ed25519 Key in Different Formats

See more Ed25519 Examples

Demonstrates how to get/save an Ed25519 private key to different formats.

Converting a private key from one format to another is done by loading in one format and saving/getting in another.

Note: This example requires Chilkat v9.5.0.83 or greater.

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.StringBuilder,
  Chilkat.EdDSA,
  Chilkat.Prng,
  Chilkat.JsonObject,
  Chilkat.PrivateKey;

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

procedure RunDemo;
var
  success: Boolean;
  eddsa: TEdDSA;
  prng: TPrng;
  privKey: TPrivateKey;
  pkcs1Base64: string;
  pkcs8Base64: string;
  password: string;
  pkcs8EncBase64: string;
  ed25519Pem: string;
  jwk: string;
  json: TJsonObject;
  ed25519_xml: string;
  sbPubKeyHex: TStringBuilder;
  privKeyHex: string;

begin
  success := False;

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

  eddsa := TEdDSA.Create;
  prng := TPrng.Create;
  privKey := TPrivateKey.Create;

  //  Generates a new ed25519 key and stores it in privKey.
  success := eddsa.GenEd25519Key(prng,privKey);
  if (success = False) then
    begin
      WriteLn(eddsa.LastErrorText);
      Exit;
    end;

  //  ----------------------------------------------------------
  //  Ed25519 PKCS1 format
  //  
  //  This is the format created by:  openssl genpkey -algorithm X25519 -out xkey.pem
  pkcs1Base64 := privKey.GetPkcs1ENC('base64');
  WriteLn(pkcs1Base64);

  //  Sample output:  MC4CAQAwBQYDK2VuBCIEIB1mwirs+eC6XGbkjPIiZyBwQ7768uSd9v5PHOLFbIXo

  //  PKCS1 is a binary ASN.1 DER format.  You can examine the contents with two online tools:
  //  1) Go to ASN.1 Decoder  and paste the base64 into the online form.
  //  2) Or Decode Base64 ASN.1 to XML 

  //  The PKCS1 ASN.1 format for an Ed25519 key look like this:
  //    SEQUENCE
  //      INTEGER 0
  //      SEQUENCE
  //        OBJECT IDENTIFIER 1.3.101.110 curveX25519 (ECDH 25519 key agreement algorithm)
  //      OCTET STRING 
  //        OCTET STRING (32 byte) 1D66C...

  //  Save it directly to a file.
  success := privKey.SavePkcs1File('qa_output/ed25519.key');

  //  ----------------------------------------------------------
  //  Ed25519 Unencrypted PKCS8 format
  //  
  //  For ed25519, the ASN.1 output is the same as for PKCS1.
  pkcs8Base64 := privKey.GetPkcs8ENC('base64');
  WriteLn(pkcs8Base64);

  //  PKCS8 is a binary ASN.1 DER format.  You can examine the contents with two online tools:
  //  1) Go to ASN.1 Decoder  and paste the base64 into the online form.
  //  2) Or Decode Base64 ASN.1 to XML 

  //  ----------------------------------------------------------
  //  Ed25519 Encrypted PKCS8 format
  //  
  //  Note: The encrypted output cannot be examined using the above online tools because the ASN.1 is encrypted.
  password := 'secret';
  pkcs8EncBase64 := privKey.GetPkcs8EncryptedENC('base64',password);
  WriteLn(pkcs8EncBase64);

  //  ----------------------------------------------------------
  //  Ed25519 in PEM format:
  //  
  ed25519Pem := privKey.GetPkcs1Pem();
  WriteLn(ed25519Pem);

  //  Sample output:

  //  -----BEGIN PRIVATE KEY-----
  //  MC4CAQAwBQYDK2VuBCIEIOKPhbULJagBAi7hbRdn1f4AAzh1RqqCHqCAvau7N6yO
  //  -----END PRIVATE KEY-----

  //  ----------------------------------------------------------
  //  Ed25519 in JWK Format
  //  
  jwk := privKey.GetJwk();

  json := TJsonObject.Create;
  json.Load(jwk);
  json.EmitCompact := False;
  WriteLn(json.Emit());

  //  Sample output:
  //  {
  //    "kty": "OKP",
  //    "crv": "Ed25519",
  //    "x": "SE2Kne5xt51z1eciMH2T2ftDQp96Gl6FhY6zSQujiP0",
  //    "d": "O-eRXewadF0sNyB0U9omcnt8Qg2ZmeK3WSXPYgqe570",
  //    "use": "sig"
  //  }

  //  In the above JWK, x is the public key, y is the private key.
  //  Both are 32 bytes and are base64-url encoded.

  //  ----------------------------------------------------------
  //  Ed25519 in XML Format
  //  
  ed25519_xml := privKey.GetXml();
  WriteLn(ed25519_xml);

  //  Sample output:  <Ed25519KeyValue>w4b/gI0zgYKgjtfWLjNfc4issmP7Qap84uesYNgEefP/WoY3jNOhOzgTYsMtOnuyGn3MdA4NZtsUXVNI1NiTlA==</Ed25519KeyValue>

  //  The base64 content is composed of the concatenation of the 32-byte private key with the 32-byte public key and then base64 encoded.
  //  In other words:  Base64(privKey || pubKey)

  //  ----------------------------------------------------------
  //  Ed25519 in Raw Hex Format
  //  
  sbPubKeyHex := TStringBuilder.Create;
  privKeyHex := privKey.GetRawHex(sbPubKeyHex);

  //  We should have a 32-byte private key (a 64 character hex string).
  WriteLn('private key = ' + privKeyHex);

  //  We should have a 32-byte public key (a 64 character hex string).
  WriteLn('public key = ' + sbPubKeyHex.GetAsString());

  //  Sample output:
  //  key type = ed25519
  //  size in bits = 256
  //  private key = d4ee72dbf913584ad5b6d8f1f769f8ad3afe7c28cbf1d4fbe097a88f44755842
  //  public key = 19bf44096984cdfe8541bac167dc3b96c85086aa30b6b6cb0c5c38ad703166e1


  eddsa.Free;
  prng.Free;
  privKey.Free;
  json.Free;
  sbPubKeyHex.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.