Key Refresh

Please refer to the Session creation section to learn how to create a new session.

Full example:

ECDSA

main.dart

import 'package:silent_shard_sdk/silent_shard_sdk.dart' as sdk;

Future<void> refresh(sdk.EcdsaSession session) async {
  // Creating a new keyshare for demo purpose. In real application, you can use an existing keyshare.
  final sdk.DklsKeyshare keyshare = await session.keygen();
  print('Keyshare created, public key: ${keyshare.publicKeyHex}');

  final sdk.DklsKeyshare refreshedKeyshare =
      await session.refresh(keyId: keyshare.keyId);

  print('Refreshed keyshare, public key: ${refreshedKeyshare.publicKeyHex}');
}

EdDSA

main.dart

import 'package:silent_shard_sdk/silent_shard_sdk.dart' as sdk;

Future<void> refresh(sdk.EddsaSession session) async {
  // Creating a new keyshare for demo purpose. In real application, you can use an existing keyshare.
  final sdk.SchnorrKeyshare keyshare = await session.keygen();
  print('Keyshare created, public key: ${keyshare.publicKeyHex}');

  final sdk.SchnorrKeyshare refreshedKeyshare =
      await session.refresh(keyId: await keyshare.keyId);

  print('Refreshed keyshare, public key: ${refreshedKeyshare.publicKeyHex}');
}

• When session.refresh(keyshare) is called, the app and the server exchange messages to "refresh" the MPC wallet. Refer to Key Refresh for more details.
• This process enhances the long-term security of the MPC wallet by proactively updating the client's and server's secret shares.
• The wallet's public address or key remains unchanged during this process.
• The refreshedKeyshare object is of type DklsKeyshare and represents the client's new share of the MPC wallet.

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During refresh, there are risks involved of loosing the complete keyshare. So to provide fallback method we added reconcile protocol.

Learn more about working of reconcile protocol.