| // 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.prf; |
| |
| import com.google.crypto.tink.proto.HashType; |
| import com.google.crypto.tink.proto.HkdfPrfKeyFormat; |
| import com.google.crypto.tink.proto.HkdfPrfParams; |
| import com.google.crypto.tink.proto.KeyTemplate; |
| import com.google.crypto.tink.proto.OutputPrefixType; |
| |
| /** |
| * Key templates for PRF-Keys. |
| * |
| * @deprecated use the key template methods in the key managers, e.g., |
| * HkdfPrfKeyManager.hkdfSha256Template(). |
| */ |
| @Deprecated |
| public final class PrfKeyTemplates { |
| |
| private PrfKeyTemplates() {} |
| |
| private static KeyTemplate createHkdfKeyTemplate() { |
| HkdfPrfKeyFormat format = |
| HkdfPrfKeyFormat.newBuilder() |
| .setKeySize(32) // the size in bytes of the HKDF key |
| .setParams(HkdfPrfParams.newBuilder().setHash(HashType.SHA256)) |
| .build(); |
| return KeyTemplate.newBuilder() |
| .setValue(format.toByteString()) |
| .setTypeUrl(HkdfPrfKeyManager.staticKeyType()) |
| .setOutputPrefixType(OutputPrefixType.RAW) |
| .build(); |
| } |
| |
| /** |
| * Generates a {@link KeyTemplate} for a {@link com.google.crypto.tink.proto.HkdfPrfKey} key with |
| * the following parameters. |
| * |
| * <ul> |
| * <li>Hash function: SHA256 |
| * <li>HMAC key size: 32 bytes |
| * <li>Salt: empty |
| * </ul> |
| */ |
| public static final KeyTemplate HKDF_SHA256 = createHkdfKeyTemplate(); |
| } |