io.jsonwebtoken.impl.crypto.RsaSignatureValidator Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of jjwt Show documentation

Legacy dependency. Please update your dependencies as documented here: https://github.com/jwtk/jjwt#installation

There is a newer version: 0.12.6

/*
 * Copyright (C) 2014 jsonwebtoken.io
 *
 * 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 io.jsonwebtoken.impl.crypto;

import io.jsonwebtoken.SignatureAlgorithm;
import io.jsonwebtoken.SignatureException;
import io.jsonwebtoken.lang.Assert;

import java.security.InvalidKeyException;
import java.security.Key;
import java.security.PublicKey;
import java.security.Signature;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.util.Arrays;

public class RsaSignatureValidator extends RsaProvider implements SignatureValidator {

    private final RsaSigner SIGNER;

    public RsaSignatureValidator(SignatureAlgorithm alg, Key key) {
        super(alg, key);
        Assert.isTrue(key instanceof RSAPrivateKey || key instanceof RSAPublicKey,
                      "RSA Signature validation requires either a RSAPublicKey or RSAPrivateKey instance.");
        this.SIGNER = key instanceof RSAPrivateKey ? new RsaSigner(alg, key) : null;
    }

    @Override
    public boolean isValid(byte[] data, byte[] signature) {
        if (key instanceof PublicKey) {
            Signature sig = createSignatureInstance();
            PublicKey publicKey = (PublicKey) key;
            try {
                return doVerify(sig, publicKey, data, signature);
            } catch (Exception e) {
                String msg = "Unable to verify RSA signature using configured PublicKey. " + e.getMessage();
                throw new SignatureException(msg, e);
            }
        } else {
            Assert.notNull(this.SIGNER, "RSA Signer instance cannot be null.  This is a bug.  Please report it.");
            byte[] computed = this.SIGNER.sign(data);
            return Arrays.equals(computed, signature);
        }
    }

    protected boolean doVerify(Signature sig, PublicKey publicKey, byte[] data, byte[] signature)
        throws InvalidKeyException, java.security.SignatureException {
        sig.initVerify(publicKey);
        sig.update(data);
        return sig.verify(signature);
    }

}