1 // Copyright 2022 Google LLC 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 // 15 //////////////////////////////////////////////////////////////////////////////// 16 17 package com.google.crypto.tink.internal; 18 19 import com.google.crypto.tink.Key; 20 import com.google.crypto.tink.PrimitiveSet; 21 import com.google.crypto.tink.PrimitiveWrapper; 22 import java.security.GeneralSecurityException; 23 import java.util.concurrent.atomic.AtomicReference; 24 25 /** 26 * A Mutable version of the {@link PrimitiveRegistry}. 27 * 28 * <p>This class probably shouldn't exist; it would be better if we had only the 29 * PrimitiveRegistry. However, at the moment, we need this, since a call to e.g. 30 * 31 * <pre> AesCmacKeyManager.register() </pre> 32 * 33 * should register such an object into a global, mutable registry. 34 */ 35 public final class MutablePrimitiveRegistry { 36 private static MutablePrimitiveRegistry globalInstance = 37 new MutablePrimitiveRegistry(); 38 globalInstance()39 public static MutablePrimitiveRegistry globalInstance() { 40 return globalInstance; 41 } 42 resetGlobalInstanceTestOnly()43 public static void resetGlobalInstanceTestOnly() { 44 globalInstance = new MutablePrimitiveRegistry(); 45 } 46 47 private final AtomicReference<PrimitiveRegistry> registry = 48 new AtomicReference<>(PrimitiveRegistry.builder().build()); 49 MutablePrimitiveRegistry()50 MutablePrimitiveRegistry() {} 51 52 /** 53 * Registers a key primitive constructor for later use in {@link #getPrimitive}. 54 * 55 * <p>This registers a primitive constructor which can later be used to create a primitive by 56 * calling {@link #getPrimitive}. If a constructor for the pair {@code (KeyT, PrimitiveT)} has 57 * already been registered and is the same, then the call is ignored; otherwise, an exception is 58 * thrown. 59 */ registerPrimitiveConstructor( PrimitiveConstructor<KeyT, PrimitiveT> constructor)60 public synchronized <KeyT extends Key, PrimitiveT> void registerPrimitiveConstructor( 61 PrimitiveConstructor<KeyT, PrimitiveT> constructor) throws GeneralSecurityException { 62 PrimitiveRegistry newRegistry = 63 PrimitiveRegistry.builder(registry.get()) 64 .registerPrimitiveConstructor(constructor) 65 .build(); 66 registry.set(newRegistry); 67 } 68 registerPrimitiveWrapper( PrimitiveWrapper<InputPrimitiveT, WrapperPrimitiveT> wrapper)69 public synchronized <InputPrimitiveT, WrapperPrimitiveT> void registerPrimitiveWrapper( 70 PrimitiveWrapper<InputPrimitiveT, WrapperPrimitiveT> wrapper) 71 throws GeneralSecurityException { 72 PrimitiveRegistry newRegistry = 73 PrimitiveRegistry.builder(registry.get()).registerPrimitiveWrapper(wrapper).build(); 74 registry.set(newRegistry); 75 } 76 77 /** 78 * Creates a primitive from a given key. 79 * 80 * <p>This will look up a previously registered constructor for the given pair of {@code (KeyT, 81 * PrimitiveT)}, and, if successful, use the registered PrimitiveConstructor object to create the 82 * requested primitive. Throws if the required constructor has not been registered, or if the 83 * primitive construction threw. 84 */ getPrimitive( KeyT key, Class<PrimitiveT> primitiveClass)85 public <KeyT extends Key, PrimitiveT> PrimitiveT getPrimitive( 86 KeyT key, Class<PrimitiveT> primitiveClass) throws GeneralSecurityException { 87 return registry.get().getPrimitive(key, primitiveClass); 88 } 89 getInputPrimitiveClass( Class<WrapperPrimitiveT> wrapperClassObject)90 public <WrapperPrimitiveT> Class<?> getInputPrimitiveClass( 91 Class<WrapperPrimitiveT> wrapperClassObject) throws GeneralSecurityException { 92 return registry.get().getInputPrimitiveClass(wrapperClassObject); 93 } 94 wrap( PrimitiveSet<InputPrimitiveT> primitives, Class<WrapperPrimitiveT> wrapperClassObject)95 public <InputPrimitiveT, WrapperPrimitiveT> WrapperPrimitiveT wrap( 96 PrimitiveSet<InputPrimitiveT> primitives, Class<WrapperPrimitiveT> wrapperClassObject) 97 throws GeneralSecurityException { 98 return registry.get().wrap(primitives, wrapperClassObject); 99 } 100 } 101