Dart

Load ECC Public Key from JWK Format (JSON Web Key)

See more ECC Examples

Demonstrates how to load an ECC public key from JWK (JSON Web Key) format.

Note: This example requires Chilkat v9.5.0.66 or later.

Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // Note: This example requires Chilkat v9.5.0.66 or later.

  // First build a JWK sample to load..
  final json = CkJsonObject();
  json.updateString('kty', 'EC');
  json.updateString('crv', 'P-256');
  json.updateString('x', 'oBUyo8CQAFPeYPvv78ylh5MwFZjTCLQeb042TjiMJxE');
  json.updateString('y', 'vvQyxZkUjJQUPU_0bCy3Pj5qQdfu8jwEfqEeYGZ95CU');

  // The JSON contains the following:
  // { 
  //   "kty": "EC",
  //   "crv": "P-256",
  //   "x": "oBUyo8CQAFPeYPvv78ylh5MwFZjTCLQeb042TjiMJxE",
  //   "y": "vvQyxZkUjJQUPU_0bCy3Pj5qQdfu8jwEfqEeYGZ95CU",
  // }

  // Note: The JSON can contain other members, such as "use", "kid", or anything else.  These will be ignored.
  json.emitCompact = false;

  // Show the JWK string to be loaded:
  final jwkStr = json.emit();

  final pubKey = CkPublicKey();
  // The LoadFromString method will automatically detect the format.
  try {
    pubKey.loadFromString(jwkStr);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // OK.. the JWK is loaded.  It can be used in whatever way desired...

  // The key can be retrieved in any other format, such as XML or PEM..
  print(pubKey.getXml());

  // XML output:
  // <ECCPublicKey curve="secp256r1" 
  //    x="A01532A3C0900053DE60FBEFEFCCA58793301598D308B41E6F4E364E388C2711" 
  //    y="BEF432C599148C94143D4FF46C2CB73E3E6A41D7EEF23C047EA11E60667DE425">
  //    MIIBSzCCAQMGByqGSM49AgEwgfcCAQEwLAYHKoZIzj0BAQIhAP////8AAAABAAAAAAAAAAAAAAAA////////////////MFsEIP////8AAAABAAAAAAAAAAAAAAAA///////////////8BCBaxjXYqjqT57PrvVV2mIa8ZR0GsMxTsPY7zjw+J9JgSwMVAMSdNgiG5wSTamZ44ROdJreBn36QBEEEaxfR8uEsQkf4vOblY6RA8ncDfYEt6zOg9KE5RdiYwpZP40Li/hp/m47n60p8D54WK84zV2sxXs7LtkBoN79R9QIhAP////8AAAAA//////////+85vqtpxeehPO5ysL8YyVRAgEBA0IABKAVMqPAkABT3mD77+/MpYeTMBWY0wi0Hm9ONk44jCcRvvQyxZkUjJQUPU/0bCy3Pj5qQdfu8jwEfqEeYGZ95CU=
  // </ECCPublicKey>

  // Choose PCKS1 or PCKS8 PEM format..
  final bPreferPkcs1 = false;
  print(pubKey.getPem(bPreferPkcs1));

  // PEM output
  // -----BEGIN PUBLIC KEY-----
  // MIIBSzCCAQMGByqGSM49AgEwgfcCAQEwLAYHKoZIzj0BAQIhAP////8AAAABAAAA
  // AAAAAAAAAAAA////////////////MFsEIP////8AAAABAAAAAAAAAAAAAAAA////
  // ///////////8BCBaxjXYqjqT57PrvVV2mIa8ZR0GsMxTsPY7zjw+J9JgSwMVAMSd
  // NgiG5wSTamZ44ROdJreBn36QBEEEaxfR8uEsQkf4vOblY6RA8ncDfYEt6zOg9KE5
  // RdiYwpZP40Li/hp/m47n60p8D54WK84zV2sxXs7LtkBoN79R9QIhAP////8AAAAA
  // //////////+85vqtpxeehPO5ysL8YyVRAgEBA0IABKAVMqPAkABT3mD77+/MpYeT
  // MBWY0wi0Hm9ONk44jCcRvvQyxZkUjJQUPU/0bCy3Pj5qQdfu8jwEfqEeYGZ95CU=
  // -----END PUBLIC KEY-----
}