chore: sync android-jca-branch with master

example/webcrypto/hmac/import_raw_key.dart

@@ -0,0 +1,31 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// ignore_for_file: unused_local_variable
+
+// #region example
+import 'dart:convert' show base64;
+
+import 'package:webcrypto/webcrypto.dart';
+
+Future<void> main() async {
+  final key = await HmacSecretKey.importRawKey(
+    base64.decode(
+      'WzIxLDg0LDEwMCw5OSwxMCwxMDUsMjIsODAsMTkwLDExNiwyMDMsMjQ5XQ==',
+    ),
+    Hash.sha256,
+  );
+}
+
+// #endregion

lib/src/boringssl/lookup/utils.dart

@@ -29,10 +29,12 @@ String get libraryFileName {
   if (Platform.isMacOS) {
     return 'lib$libraryName.dylib';
   }
+  // coverage:ignore-start
   throw UnsupportedError(
     'Platform ${Platform.operatingSystem} is unsupported or embed '
     'the binary webcrypto library for package:webcrypto',
   );
+  // coverage:ignore-end
 }
 
 /// Look for the webcrypto binary library in the `.dart_tool/webcrypto/` folder.

lib/src/impl_ffi/impl_ffi.aes_common.dart

@@ -18,7 +18,9 @@ Uint8List _aesImportRawKey(List<int> keyData) {
   if (keyData.length == 24) {
     // 192-bit AES is intentionally unsupported, see https://crbug.com/533699
     // If not supported in Chrome, there is not reason to support it in Dart.
+    // coverage:ignore-start
     throw UnsupportedError('192-bit AES keys are not supported');
+    // coverage:ignore-end
   }
   if (keyData.length != 16 && keyData.length != 32) {
     throw const FormatException('keyData for AES must be 128 or 256 bits');
@@ -43,7 +45,9 @@ Uint8List _aesImportJwkKey(
   if (keyData.length == 24) {
     // 192-bit AES is intentionally unsupported, see https://crbug.com/533699
     // If not supported in Chrome, there is not reason to support it in Dart.
+    // coverage:ignore-start
     throw UnsupportedError('192-bit AES keys are not supported');
+    // coverage:ignore-end
   }
   checkJwk(
     keyData.length == 16 || keyData.length == 32,
@@ -82,7 +86,9 @@ Uint8List _aesGenerateKey(int length) {
   if (length == 192) {
     // 192-bit AES is intentionally unsupported, see https://crbug.com/533699
     // If not supported in Chrome, there is not reason to support it in Dart.
+    // coverage:ignore-start
     throw UnsupportedError('192-bit AES keys are not supported');
+    // coverage:ignore-end
   }
   if (length != 128 && length != 256) {
     throw const FormatException('keyData for AES must be 128 or 256 bits');

lib/src/impl_ffi/impl_ffi.digest.dart

@@ -74,7 +74,7 @@ abstract class _HashImpl implements HashImpl {
 
   /// Algorithm (`alg` for JWK) when this hash algorithm is used in RSA-OAEP.
   ///
-  /// For SHA-1, it returns 'RSA-OAEP-1'.
+  /// For SHA-1, it returns 'RSA-OAEP'.
   /// For SHA-256, it returns 'RSA-OAEP-256'.
   /// For SHA-384, it returns 'RSA-OAEP-384'.
   /// For SHA-512, it returns 'RSA-OAEP-512'.
@@ -113,7 +113,7 @@ final class _Sha1 extends _HashImpl {
   String get hmacJwkAlg => 'HS1';
 
   @override
-  String get rsaOaepJwkAlg => 'RSA-OAEP-1';
+  String get rsaOaepJwkAlg => 'RSA-OAEP';
 
   @override
   String get rsaPssJwkAlg => 'PS1';

lib/src/impl_ffi/impl_ffi.ec_common.dart

@@ -26,7 +26,9 @@ int _ecCurveToNID(EllipticCurve curve) {
     return NID_secp521r1;
   }
   // This should never happen!
+  // coverage:ignore-start
   throw UnsupportedError('curve "$curve" is not supported');
+  // coverage:ignore-end
 }
 
 /// Get [EllipticCurve] from matching BoringSSL `ssl.NID_...`.
@@ -41,7 +43,9 @@ EllipticCurve _ecCurveFromNID(int nid) {
     return EllipticCurve.p521;
   }
   // This should never happen!
+  // coverage:ignore-start
   throw operationError('internal error detecting curve');
+  // coverage:ignore-end
 }
 
 String _ecCurveToJwkCrv(EllipticCurve curve) {
@@ -55,7 +59,9 @@ String _ecCurveToJwkCrv(EllipticCurve curve) {
     return 'P-521';
   }
   // This should never happen!
+  // coverage:ignore-start
   throw UnsupportedError('curve "$curve" is not supported');
+  // coverage:ignore-end
 }
 
 /// Perform some post-import validation for EC keys.

lib/src/impl_ffi/impl_ffi.ecdh.dart

@@ -111,8 +111,8 @@ final class _EcdhPrivateKeyImpl implements EcdhPrivateKeyImpl {
         'custom implementations of EcdhPublicKey is not supported',
       );
     }
-    if (length <= 0) {
-      throw ArgumentError.value(length, 'length', 'must be positive');
+    if (length < 0) {
+      throw ArgumentError.value(length, 'length', 'must be non-negative');
     }
 
     return _Scope.async((scope) async {

lib/src/impl_ffi/impl_ffi.ecdsa.dart

@@ -29,7 +29,9 @@ String _ecdsaCurveToJwkAlg(EllipticCurve curve) {
     return 'ES512';
   }
   // This should never happen!
+  // coverage:ignore-start
   throw UnsupportedError('curve "$curve" is not supported');
+  // coverage:ignore-end
 }
 
 Future<EcdsaPrivateKeyImpl> ecdsaPrivateKey_importPkcs8Key(

lib/src/impl_ffi/impl_ffi.pbkdf2.dart

@@ -60,16 +60,14 @@ final class _Pbkdf2SecretKeyImpl implements Pbkdf2SecretKeyImpl {
         'The length for PBKDF2 must be a multiple of 8 bits',
       );
     }
-    if (length == 0) {
-      throw operationError(
-        'A length of zero is not allowed Pbkdf2SecretKey.deriveBits',
-      );
-    }
     if (iterations <= 0) {
       throw operationError(
         'Iterations <= 0 is not allowed for Pbkdf2SecretKey.deriveBits',
       );
     }
+    if (length == 0) {
+      return Uint8List(0);
+    }
 
     final lengthInBytes = length ~/ 8;
 

lib/src/impl_js/impl_js.utils.dart

@@ -45,8 +45,10 @@ String _curveToName(EllipticCurve curve) {
       return 'P-521';
   }
   // This should never happen.
+  // coverage:ignore-start
   // ignore: dead_code
   throw AssertionError('Unknown curve "$curve"');
+  // coverage:ignore-end
 }
 
 Object _translateDomException(

lib/src/impl_stub/impl_stub.aescbc.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticAesCbcSecretKeyImpl implements StaticAesCbcSecretKeyImpl {

lib/src/impl_stub/impl_stub.aesctr.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticAesCtrSecretKeyImpl implements StaticAesCtrSecretKeyImpl {

lib/src/impl_stub/impl_stub.aesgcm.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticAesGcmSecretKeyImpl implements StaticAesGcmSecretKeyImpl {

lib/src/impl_stub/impl_stub.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 library;
 
 import 'dart:typed_data';

lib/src/impl_stub/impl_stub.digest.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _HashImpl implements HashImpl {

lib/src/impl_stub/impl_stub.ecdh.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticEcdhPrivateKeyImpl implements StaticEcdhPrivateKeyImpl {

lib/src/impl_stub/impl_stub.ecdsa.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticEcdsaPrivateKeyImpl implements StaticEcdsaPrivateKeyImpl {

lib/src/impl_stub/impl_stub.hkdf.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticHkdfSecretKeyImpl implements StaticHkdfSecretKeyImpl {

lib/src/impl_stub/impl_stub.hmac.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticHmacSecretKeyImpl implements StaticHmacSecretKeyImpl {

lib/src/impl_stub/impl_stub.pbkdf2.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticPbkdf2SecretKeyImpl implements StaticPbkdf2SecretKeyImpl {

lib/src/impl_stub/impl_stub.random.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _RandomImpl implements RandomImpl {

lib/src/impl_stub/impl_stub.rsaoaep.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticRsaOaepPrivateKeyImpl

lib/src/impl_stub/impl_stub.rsapss.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticRsaPssPrivateKeyImpl implements StaticRsaPssPrivateKeyImpl {

lib/src/impl_stub/impl_stub.rsassapkcs1v15.dart

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// coverage:ignore-file
 part of 'impl_stub.dart';
 
 final class _StaticRsaSsaPkcs1V15PrivateKeyImpl

lib/src/testing/regression/derive_bits_zero_length.dart

@@ -0,0 +1,42 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'dart:typed_data';
+
+import 'package:webcrypto/webcrypto.dart';
+import '../utils/utils.dart';
+
+List<({String name, Future<void> Function() test})> tests() => [
+  (
+    name: 'ECDH derives an empty secret when length is zero',
+    test: () async {
+      final alice = await EcdhPrivateKey.generateKey(EllipticCurve.p256);
+      final bob = await EcdhPrivateKey.generateKey(EllipticCurve.p256);
+
+      final secret = await alice.privateKey.deriveBits(0, bob.publicKey);
+
+      check(secret.isEmpty, 'Expected an empty ECDH secret');
+    },
+  ),
+  (
+    name: 'PBKDF2 derives an empty secret when length is zero',
+    test: () async {
+      final key = await Pbkdf2SecretKey.importRawKey(Uint8List(16));
+
+      final secret = await key.deriveBits(0, Hash.sha256, Uint8List(16), 1);
+
+      check(secret.isEmpty, 'Expected an empty PBKDF2 secret');
+    },
+  ),
+];