Pascal (Lazarus/Delphi)

How to Generate a JSON Web Key (JWK)

See more JSON Web Signatures (JWS) Examples

Demonstrates how to generate the following types of JSON Web Keys:

• RSA key pair
• EC key pair
• Octet sequence key (HMAC-256)
• 192-bit AES GCM key

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.Prng,
  Chilkat.Crypt2,
  Chilkat.JsonObject,
  Chilkat.PrivateKey,
  Chilkat.Rsa,
  Chilkat.Ecc;

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

procedure RunDemo;
var
  success: Boolean;
  rsa: TRsa;
  rsaKey: TPrivateKey;
  rsaJwkStr: string;
  json: TJsonObject;
  prng: TPrng;
  ecc: TEcc;
  ecKey: TPrivateKey;
  ecJwkStr: string;
  crypt: TCrypt2;
  jwkHmac: TJsonObject;
  jwkAes: TJsonObject;

begin
  success := False;

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

  //  ----------------------------------------------
  //  Generate an RSA key pair in JWK format.
  //  (Examples for generating other key types are shown below...)
  rsa := TRsa.Create;
  rsaKey := TPrivateKey.Create;
  success := rsa.GenKey(2048,rsaKey);
  if (success = False) then
    begin
      WriteLn(rsa.LastErrorText);
      Exit;
    end;

  rsaJwkStr := rsaKey.GetJwk();

  //  The string returned is the most compact possible, and therefore it is not
  //  very readable.  To pretty-print, load into a JSON object and emit..
  json := TJsonObject.Create;
  json.EmitCompact := False;
  json.Load(rsaJwkStr);
  WriteLn(json.Emit());

  //  Sample RSA JWK:

  //  { 
  //    "kty": "RSA",
  //    "n": "6w1Xpof7gKmytJ3yc_yjI5_K3MvVXnBYBDy5Oh2W6Xqu_fOl3W18SjS2AU5xJrTHlB_j84yQjPyXJh_ixjACK4K4dCSYqlLmn3R7QJ84vnHLIEkqwUICqOHdCBjK5xhMrdZxIhuNlJzbARY-3u9RqjsT3HYTjA6JNHUWTYBBRou4gYGm4cJgvX4uexdikqxnze014RmZMaOV_4MR--WL4G8QfNJ2pRBEXQeKyije89H6M5oTSK7KZqFTIqu9hwNtx2oGpGAIcS0Jv5xVl-hDtwXZNwQJaOxMzLw1nwnb2kMliJa67EabQFrQY_xthQNsfzcHJJlpqYiMprW8wRkzmQ",
  //    "e": "AQAB",
  //    "d": "1_bnXMw-SeYhmxAwb19lqVqtMpdaES5ZwHLmoT4EpbsiQ5T1BfENrMSnoaWoEy8w3Kk8cU7qlY-TdOUBIKWFqOKvhY8GciA_Y6zLfgGNSnYVczGmxfBXr0HvKvxUmWZbNbH9OqBkQnKoSmRdGcp7l1Q2mG4o4ZuNdxRJjKXV0_DTrNLUJzst0hsfoZ6mWUrQcn39XGvvLjz9ySS-DYGI1vli3ayx8jVNuw0rU8UXVs9WmPQLvZO_ZDMhoLEeKsdejnNkUNPAUjqxcSOZRojt4BfCmbt-_1slFb0NsoaqnDVZGezd9J9ocxGuyIWHAJu9GGZEcdaFyiDDs_WA1IS_fQ",
  //    "p": "9dU8f6yOklRcpV6ayVMKpyQ6AMuBTF3rZmB498eAvvTkVG1-upm8IkikTVNpPjEalc82Sxuq8oF4N5x1-F33sgVEoCZG-1WFZTn-rnPnXSALES9hqSaVYEwnh61EiY8ckjBVr9jD2nL1JKdbfgVVeo69-9PdjnKYYDVL8eLNPwM",
  //    "q": "9MX2sW0GyaOsZ86AYe3eG2ZgcgKHvhJa573gih5Jvi2e-Nv-L0EVK29_DA7n0Pjm-gl9zVAsGsMMkphJyEF9QgyUlJ-59XLqWnECS5gO6WZdtHrJxVvcO-_AOrLIxeYnYcwhmaVaxs_UEpqGzupKHCWgf4cfXe49lrIsqGKH4jM",
  //    "dp": "IQgj9uvSxGq9gCL0HXUhC1Bc0tqFZyN_i-QOnQybig0R2R5VVvFtTBYCrbk1fPvQHK0ZGIKBN9CZvK8zUsodjDgU_ofmJcNaBz4BsKM2RVcW5Zo-PyJGFAhnj12CxhEKv8Hq4ZP4zROBSQmLy6Uf1TX05S-Up51SSCshJ0FYXs0",
  //    "dq": "RijsMiUfGfL5OvP85pUI4e-xW1yQThHyzpQlZVGTL5jiBVEBhcfw6ndWAj3Pgp2ljyvjTFNboPwhgW93Tpg-8AytFgDGi605sVzNHJ_kPlBiMZY0eYaAFQn-npSaaecziJu7UdAMugneLsruMycCwRij7Ynsmr7sFmLR3B4J9vM",
  //    "qi": "jZE-a1pa8YjflpCSH5oqp1f6f6I6-hpZcLdamLCoAcjVSIPk86gtXtOFES4411-DqYzYIZM6B_g_SRYY6JpKAOuZ40mmMTlnIEoVf8BHiGl3g6bBAiN1yQGXrwXJsg2OYnocyRA-xWNdcMSSFA52SwEdar2Mmw29qVzxtC1QbpA"
  //  }

  //  ----------------------------------------------
  //  Generate an EC P-256 key pair in JWK format

  prng := TPrng.Create;
  ecc := TEcc.Create;
  ecKey := TPrivateKey.Create;
  ecc.GenKey('P-256',prng,ecKey);

  ecJwkStr := ecKey.GetJwk();
  json.Load(ecJwkStr);
  WriteLn(json.Emit());

  //  Sample EC JWK Key:
  //  { 
  //    "kty": "EC",
  //    "crv": "P-256",
  //    "x": "tDeeYABgKEAbWicYPCEEI8sP4SRIhHKcHDW7VqrB4LA",
  //    "y": "J08HOoIZ0rX2Me3bNFZUltfxIk1Hrc8FsLu8VaSxsMI",
  //    "d": "-bqt1T0wNAN8sP5ruycQZRVlMlt3V_dSwlJ60xAX5io"
  //  }

  //  ----------------------------------------------
  //  Octet sequence keys are intended for representing secret keys, such as HMAC keys and AES keys.

  //  We'll use crypt to generate a random UUID..
  crypt := TCrypt2.Create;

  //  AES and HMAC keys are simply random arrays of bytes
  //  For these, we can just build the JSON directly,
  //  with the help of the PRNG object.

  jwkHmac := TJsonObject.Create;
  jwkHmac.EmitCompact := False;

  //  Generate a 256-bit HMAK key (32 bytes)
  jwkHmac.AppendString('kty','oct');
  //  Give the key an optional ID, which can be anything, even strings as simple as "1", "2", etc.
  jwkHmac.AppendString('kid',crypt.GenerateUuid());
  //  Indicate the intended key alg (optional)
  jwkHmac.AppendString('alg','HS256');
  //  Generate the actual key bytes
  jwkHmac.AppendString('k',prng.GenRandom(32,'base64url'));

  WriteLn(jwkHmac.Emit());

  //  Sample HMAC-256 JWK:

  //  { 
  //    "kty": "oct",
  //    "kid": "06c2515d-41fb-e436-e405-3abb361f5f7a",
  //    "alg": "HS256",
  //    "k": "wR32w7yiMe5Lhb1vkW2koBpoMxpXTFYuxOYCCIEKjdE"
  //  }

  //  ----------------------------------------------
  //  Now generate a 192-bit (24 byte) key that could be used with AES192GCM

  jwkAes := TJsonObject.Create;
  jwkAes.EmitCompact := False;

  jwkAes.AppendString('kty','oct');
  jwkAes.AppendString('kid','2');
  jwkAes.AppendString('k',prng.GenRandom(24,'base64url'));

  WriteLn(jwkAes.Emit());

  //  Sample AES key:
  //  { 
  //    "kty": "oct",
  //    "kid": "2",
  //    "k": "akAkq-L_ZTZ6-tEIhDUMtU2ENhsEgL-p"
  //  }


  rsa.Free;
  rsaKey.Free;
  json.Free;
  prng.Free;
  ecc.Free;
  ecKey.Free;
  crypt.Free;
  jwkHmac.Free;
  jwkAes.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.