| // Copyright 2021 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. |
| // |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| package com.google.crypto.tink.hybrid.internal; |
| |
| import com.google.crypto.tink.HybridDecrypt; |
| import com.google.crypto.tink.KeyTemplate; |
| import com.google.crypto.tink.Registry; |
| import com.google.crypto.tink.internal.KeyTypeManager; |
| import com.google.crypto.tink.internal.PrimitiveFactory; |
| import com.google.crypto.tink.internal.PrivateKeyTypeManager; |
| import com.google.crypto.tink.proto.HpkeAead; |
| import com.google.crypto.tink.proto.HpkeKdf; |
| import com.google.crypto.tink.proto.HpkeKem; |
| import com.google.crypto.tink.proto.HpkeKeyFormat; |
| import com.google.crypto.tink.proto.HpkeParams; |
| import com.google.crypto.tink.proto.HpkePrivateKey; |
| import com.google.crypto.tink.proto.HpkePublicKey; |
| import com.google.crypto.tink.proto.KeyData.KeyMaterialType; |
| import com.google.crypto.tink.subtle.Validators; |
| import com.google.crypto.tink.subtle.X25519; |
| import com.google.protobuf.ByteString; |
| import com.google.protobuf.ExtensionRegistryLite; |
| import com.google.protobuf.InvalidProtocolBufferException; |
| import java.security.GeneralSecurityException; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| /** |
| * Key manager that generates new {@link HpkePrivateKey} keys and produces new instances of {@link |
| * HpkeDecrypt} primitives. |
| */ |
| public final class HpkePrivateKeyManager |
| extends PrivateKeyTypeManager<HpkePrivateKey, HpkePublicKey> { |
| public HpkePrivateKeyManager() { |
| super( |
| HpkePrivateKey.class, |
| HpkePublicKey.class, |
| new PrimitiveFactory<HybridDecrypt, HpkePrivateKey>(HybridDecrypt.class) { |
| @Override |
| public HybridDecrypt getPrimitive(HpkePrivateKey recipientPrivateKey) |
| throws GeneralSecurityException { |
| return HpkeDecrypt.createHpkeDecrypt(recipientPrivateKey); |
| } |
| }); |
| } |
| |
| /** |
| * Registers an {@link HpkePrivateKeyManager} and an {@link HpkePublicKeyManager} with the |
| * registry, so that HpkePrivateKey and HpkePublicKey key types can be used with Tink. |
| */ |
| public static void registerPair(boolean newKeyAllowed) throws GeneralSecurityException { |
| Registry.registerAsymmetricKeyManagers( |
| new HpkePrivateKeyManager(), new HpkePublicKeyManager(), newKeyAllowed); |
| } |
| |
| @Override |
| public String getKeyType() { |
| return "type.googleapis.com/google.crypto.tink.HpkePrivateKey"; |
| } |
| |
| @Override |
| public int getVersion() { |
| return 0; |
| } |
| |
| @Override |
| public HpkePublicKey getPublicKey(HpkePrivateKey key) { |
| return key.getPublicKey(); |
| } |
| |
| @Override |
| public KeyMaterialType keyMaterialType() { |
| return KeyMaterialType.ASYMMETRIC_PRIVATE; |
| } |
| |
| @Override |
| public HpkePrivateKey parseKey(ByteString byteString) throws InvalidProtocolBufferException { |
| return HpkePrivateKey.parseFrom(byteString, ExtensionRegistryLite.getEmptyRegistry()); |
| } |
| |
| @Override |
| public void validateKey(HpkePrivateKey key) throws GeneralSecurityException { |
| if (key.getPrivateKey().isEmpty()) { |
| throw new GeneralSecurityException("Private key is empty."); |
| } |
| if (!key.hasPublicKey()) { |
| throw new GeneralSecurityException("Missing public key."); |
| } |
| Validators.validateVersion(key.getVersion(), getVersion()); |
| HpkeUtil.validateParams(key.getPublicKey().getParams()); |
| } |
| |
| @Override |
| public KeyTypeManager.KeyFactory<HpkeKeyFormat, HpkePrivateKey> keyFactory() { |
| return new KeyTypeManager.KeyFactory<HpkeKeyFormat, HpkePrivateKey>(HpkeKeyFormat.class) { |
| @Override |
| public void validateKeyFormat(HpkeKeyFormat keyFormat) throws GeneralSecurityException { |
| HpkeUtil.validateParams(keyFormat.getParams()); |
| } |
| |
| @Override |
| public HpkeKeyFormat parseKeyFormat(ByteString byteString) |
| throws InvalidProtocolBufferException { |
| return HpkeKeyFormat.parseFrom(byteString, ExtensionRegistryLite.getEmptyRegistry()); |
| } |
| |
| @Override |
| public HpkePrivateKey createKey(HpkeKeyFormat keyFormat) throws GeneralSecurityException { |
| byte[] privateKeyBytes = X25519.generatePrivateKey(); |
| byte[] publicKeyBytes = X25519.publicFromPrivate(privateKeyBytes); |
| |
| HpkePublicKey publicKey = |
| HpkePublicKey.newBuilder() |
| .setVersion(getVersion()) |
| .setParams(keyFormat.getParams()) |
| .setPublicKey(ByteString.copyFrom(publicKeyBytes)) |
| .build(); |
| |
| return HpkePrivateKey.newBuilder() |
| .setVersion(getVersion()) |
| .setPublicKey(publicKey) |
| .setPrivateKey(ByteString.copyFrom(privateKeyBytes)) |
| .build(); |
| } |
| |
| @Override |
| public Map<String, KeyFactory.KeyFormat<HpkeKeyFormat>> keyFormats() { |
| Map<String, KeyFactory.KeyFormat<HpkeKeyFormat>> result = new HashMap<>(); |
| result.put( |
| "DHKEM_X25519_HKDF_SHA256_HKDF_SHA256_AES_128_GCM", |
| createKeyFormat( |
| HpkeKem.DHKEM_X25519_HKDF_SHA256, |
| HpkeKdf.HKDF_SHA256, |
| HpkeAead.AES_128_GCM, |
| KeyTemplate.OutputPrefixType.TINK)); |
| result.put( |
| "DHKEM_X25519_HKDF_SHA256_HKDF_SHA256_AES_128_GCM_RAW", |
| createKeyFormat( |
| HpkeKem.DHKEM_X25519_HKDF_SHA256, |
| HpkeKdf.HKDF_SHA256, |
| HpkeAead.AES_128_GCM, |
| KeyTemplate.OutputPrefixType.RAW)); |
| result.put( |
| "DHKEM_X25519_HKDF_SHA256_HKDF_SHA256_AES_256_GCM", |
| createKeyFormat( |
| HpkeKem.DHKEM_X25519_HKDF_SHA256, |
| HpkeKdf.HKDF_SHA256, |
| HpkeAead.AES_256_GCM, |
| KeyTemplate.OutputPrefixType.TINK)); |
| result.put( |
| "DHKEM_X25519_HKDF_SHA256_HKDF_SHA256_AES_256_GCM_RAW", |
| createKeyFormat( |
| HpkeKem.DHKEM_X25519_HKDF_SHA256, |
| HpkeKdf.HKDF_SHA256, |
| HpkeAead.AES_256_GCM, |
| KeyTemplate.OutputPrefixType.RAW)); |
| result.put( |
| "DHKEM_X25519_HKDF_SHA256_HKDF_SHA256_CHACHA20_POLY1305", |
| createKeyFormat( |
| HpkeKem.DHKEM_X25519_HKDF_SHA256, |
| HpkeKdf.HKDF_SHA256, |
| HpkeAead.CHACHA20_POLY1305, |
| KeyTemplate.OutputPrefixType.TINK)); |
| result.put( |
| "DHKEM_X25519_HKDF_SHA256_HKDF_SHA256_CHACHA20_POLY1305_RAW", |
| createKeyFormat( |
| HpkeKem.DHKEM_X25519_HKDF_SHA256, |
| HpkeKdf.HKDF_SHA256, |
| HpkeAead.CHACHA20_POLY1305, |
| KeyTemplate.OutputPrefixType.RAW)); |
| result.put( |
| "DHKEM_P256_HKDF_SHA256_HKDF_SHA256_AES_128_GCM", |
| createKeyFormat( |
| HpkeKem.DHKEM_P256_HKDF_SHA256, |
| HpkeKdf.HKDF_SHA256, |
| HpkeAead.AES_128_GCM, |
| KeyTemplate.OutputPrefixType.TINK)); |
| result.put( |
| "DHKEM_P256_HKDF_SHA256_HKDF_SHA256_AES_128_GCM_RAW", |
| createKeyFormat( |
| HpkeKem.DHKEM_P256_HKDF_SHA256, |
| HpkeKdf.HKDF_SHA256, |
| HpkeAead.AES_128_GCM, |
| KeyTemplate.OutputPrefixType.RAW)); |
| result.put( |
| "DHKEM_P256_HKDF_SHA256_HKDF_SHA256_AES_256_GCM", |
| createKeyFormat( |
| HpkeKem.DHKEM_P256_HKDF_SHA256, |
| HpkeKdf.HKDF_SHA256, |
| HpkeAead.AES_256_GCM, |
| KeyTemplate.OutputPrefixType.TINK)); |
| result.put( |
| "DHKEM_P256_HKDF_SHA256_HKDF_SHA256_AES_256_GCM_RAW", |
| createKeyFormat( |
| HpkeKem.DHKEM_P256_HKDF_SHA256, |
| HpkeKdf.HKDF_SHA256, |
| HpkeAead.AES_256_GCM, |
| KeyTemplate.OutputPrefixType.RAW)); |
| result.put( |
| "DHKEM_P384_HKDF_SHA384_HKDF_SHA384_AES_128_GCM", |
| createKeyFormat( |
| HpkeKem.DHKEM_P384_HKDF_SHA384, |
| HpkeKdf.HKDF_SHA384, |
| HpkeAead.AES_128_GCM, |
| KeyTemplate.OutputPrefixType.TINK)); |
| result.put( |
| "DHKEM_P384_HKDF_SHA384_HKDF_SHA384_AES_128_GCM_RAW", |
| createKeyFormat( |
| HpkeKem.DHKEM_P384_HKDF_SHA384, |
| HpkeKdf.HKDF_SHA384, |
| HpkeAead.AES_128_GCM, |
| KeyTemplate.OutputPrefixType.RAW)); |
| result.put( |
| "DHKEM_P384_HKDF_SHA384_HKDF_SHA384_AES_256_GCM", |
| createKeyFormat( |
| HpkeKem.DHKEM_P384_HKDF_SHA384, |
| HpkeKdf.HKDF_SHA384, |
| HpkeAead.AES_256_GCM, |
| KeyTemplate.OutputPrefixType.TINK)); |
| result.put( |
| "DHKEM_P384_HKDF_SHA384_HKDF_SHA384_AES_256_GCM_RAW", |
| createKeyFormat( |
| HpkeKem.DHKEM_P384_HKDF_SHA384, |
| HpkeKdf.HKDF_SHA384, |
| HpkeAead.AES_256_GCM, |
| KeyTemplate.OutputPrefixType.RAW)); |
| result.put( |
| "DHKEM_P521_HKDF_SHA512_HKDF_SHA512_AES_128_GCM", |
| createKeyFormat( |
| HpkeKem.DHKEM_P521_HKDF_SHA512, |
| HpkeKdf.HKDF_SHA512, |
| HpkeAead.AES_128_GCM, |
| KeyTemplate.OutputPrefixType.TINK)); |
| result.put( |
| "DHKEM_P521_HKDF_SHA512_HKDF_SHA512_AES_128_GCM_RAW", |
| createKeyFormat( |
| HpkeKem.DHKEM_P521_HKDF_SHA512, |
| HpkeKdf.HKDF_SHA512, |
| HpkeAead.AES_128_GCM, |
| KeyTemplate.OutputPrefixType.RAW)); |
| result.put( |
| "DHKEM_P521_HKDF_SHA512_HKDF_SHA512_AES_256_GCM", |
| createKeyFormat( |
| HpkeKem.DHKEM_P521_HKDF_SHA512, |
| HpkeKdf.HKDF_SHA512, |
| HpkeAead.AES_256_GCM, |
| KeyTemplate.OutputPrefixType.TINK)); |
| result.put( |
| "DHKEM_P521_HKDF_SHA512_HKDF_SHA512_AES_256_GCM_RAW", |
| createKeyFormat( |
| HpkeKem.DHKEM_P521_HKDF_SHA512, |
| HpkeKdf.HKDF_SHA512, |
| HpkeAead.AES_256_GCM, |
| KeyTemplate.OutputPrefixType.RAW)); |
| return Collections.unmodifiableMap(result); |
| } |
| }; |
| } |
| |
| private static KeyFactory.KeyFormat<HpkeKeyFormat> createKeyFormat( |
| HpkeKem kem, HpkeKdf kdf, HpkeAead aead, KeyTemplate.OutputPrefixType prefixType) { |
| HpkeParams params = HpkeParams.newBuilder().setKem(kem).setKdf(kdf).setAead(aead).build(); |
| return new KeyFactory.KeyFormat<>( |
| HpkeKeyFormat.newBuilder().setParams(params).build(), prefixType); |
| } |
| } |
