importJsonWebKey static method

Future<AesGcmSecretKey> importJsonWebKey(
  1. Map<String, dynamic> jwk
)

Import an AesGcmSecretKey from JSON Web Key.

JSON Web Keys imported using AesGcmSecretKey.importJsonWebKey must have "kty": "oct", and the "alg" property of the imported jwk must be either:

  • "alg": "A128GCM" for AES-128, or
  • "alg": "A256GCM" for AES-256.

Support for AES-192 (24 byte keys) is intentionally omitted, in line with the decision not support AES-192 in Chrome.

If specified the "use" property of the imported jwk must be "use": "sig".

Throws FormatException if jwk is invalid.

Example

import 'dart:convert' show jsonEncode, jsonDecode;
import 'package:webcrypto/webcrypto.dart';

// JSON Web Key as a string containing JSON.
final jwk = '{"kty": "oct", "alg": "A256GCM", "k": ...}';

// Import secret key from decoded JSON.
final key = await AesGcmSecretKey.importJsonWebKey(jsonDecode(jwk));

// Export the key (print it in same format as it was given).
Map<String, dynamic> keyData = await key.exportJsonWebKey();
print(jsonEncode(keyData));

Implementation

static Future<AesGcmSecretKey> importJsonWebKey(
    Map<String, dynamic> jwk) async {
  final impl = await webCryptImpl.aesGcmSecretKey.importJsonWebKey(jwk);
  return AesGcmSecretKey._(impl);
}