| // Copyright 2017 Google Inc. |
| // |
| // 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.subtle; |
| |
| import com.google.crypto.tink.PublicKeyVerify; |
| import com.google.crypto.tink.subtle.EllipticCurves.EcdsaEncoding; |
| import com.google.crypto.tink.subtle.Enums.HashType; |
| import java.security.GeneralSecurityException; |
| import java.security.Signature; |
| import java.security.interfaces.ECPublicKey; |
| import java.security.spec.EllipticCurve; |
| |
| /** |
| * ECDSA verifying with JCE. |
| * |
| * @since 1.0.0 |
| */ |
| public final class EcdsaVerifyJce implements PublicKeyVerify { |
| private final ECPublicKey publicKey; |
| private final String signatureAlgorithm; |
| private final EcdsaEncoding encoding; |
| |
| public EcdsaVerifyJce(final ECPublicKey pubKey, HashType hash, EcdsaEncoding encoding) |
| throws GeneralSecurityException { |
| EllipticCurves.checkPublicKey(pubKey); |
| this.signatureAlgorithm = SubtleUtil.toEcdsaAlgo(hash); |
| this.publicKey = pubKey; |
| this.encoding = encoding; |
| } |
| |
| @Override |
| public void verify(final byte[] signature, final byte[] data) throws GeneralSecurityException { |
| byte[] derSignature = signature; |
| if (encoding == EcdsaEncoding.IEEE_P1363) { |
| EllipticCurve curve = publicKey.getParams().getCurve(); |
| if (signature.length != 2 * EllipticCurves.fieldSizeInBytes(curve)) { |
| throw new GeneralSecurityException("Invalid signature"); |
| } |
| derSignature = EllipticCurves.ecdsaIeee2Der(signature); |
| } |
| if (!EllipticCurves.isValidDerEncoding(derSignature)) { |
| throw new GeneralSecurityException("Invalid signature"); |
| } |
| Signature verifier = EngineFactory.SIGNATURE.getInstance(signatureAlgorithm); |
| verifier.initVerify(publicKey); |
| verifier.update(data); |
| boolean verified = false; |
| try { |
| verified = verifier.verify(derSignature); |
| } catch (java.lang.RuntimeException ex) { |
| verified = false; |
| } |
| if (!verified) { |
| throw new GeneralSecurityException("Invalid signature"); |
| } |
| } |
| } |