chainkey_platform_interface 0.2.0

Common platform interface for the chainkey federated plugin.

chainkey_platform_interface

A common platform interface for the chainkey federated plugin.

This package defines the core abstractions, data models, exceptions, and Pigeon-generated host API contracts implemented by platform-specific packages (chainkey_android, chainkey_ios, and chainkey_web).

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Architecture Overview

chainkey uses the federated plugin architecture. Platform implementations extend ChainkeyPlatform to handle native hardware-isolated security enclaves and WebAuthn authenticators:

• App-facing package: chainkey
• Platform interface: chainkey_platform_interface (this package)
• Android implementation: chainkey_android
• iOS implementation: chainkey_ios
• Web implementation: chainkey_web

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Core Models

HardwareIsolationLevel

Defines the hardware security boundary protecting the cryptographic keypair:

• secureEnclave: Apple Secure Enclave Processor (SEP).
• strongBox: Dedicated hardware security chip (Android StrongBox Keymaster / KeyMint).
• tee: Trusted Execution Environment (Android ARM TrustZone).
• software: Platform keystore or browser-managed software sandbox.

EnclavePublicKey

Represents an elliptic curve public key generated within the enclave:

• x: 32-byte big-endian X-coordinate on the NIST P-256 (secp256r1) curve.
• y: 32-byte big-endian Y-coordinate on the NIST P-256 curve.
• uncompressedBytes: 65-byte uncompressed SEC1 representation (0x04 || X || Y).
• isolationLevel: Confirmed isolation level.

DerSignatureResult

Cryptographic signature produced by the enclave:

• rawDerSignature: ASN.1 DER-encoded signature bytes.
• r: 32-byte big-endian scalar component.
• s: 32-byte big-endian scalar component.
• isLowS: Indicates whether $s$ is normalized to low-$S$ ($s \le n/2$) per BIP-62 / EIP-2.

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Usage for Platform Implementers

To implement a new platform for chainkey, extend ChainkeyPlatform:

import 'package:chainkey_platform_interface/chainkey_platform_interface.dart';

class CustomChainkeyPlatform extends ChainkeyPlatform {
  static void registerWith() {
    ChainkeyPlatform.instance = CustomChainkeyPlatform();
  }

  @override
  Future<bool> isHardwareIsolationSupported(HardwareIsolationLevel level) async {
    // Custom platform isolation check
    return true;
  }
}

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Issues & Contributing

For issues, bug reports, and feature requests, please visit the Chainkey GitHub Repository.