src/main/java/org/apache/sling/cli/impl/pgp/SHA1HashValidator.java

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 ~ Licensed to the Apache Software Foundation (ASF) under one
 ~ or more contributor license agreements.  See the NOTICE file
 ~ distributed with this work for additional information
 ~ regarding copyright ownership.  The ASF licenses this file
 ~ to you 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
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package org.apache.sling.cli.impl.pgp;

import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import org.bouncycastle.util.encoders.Hex;
import org.osgi.service.component.annotations.Component;

@Component(service = SHA1HashValidator.class)
public class SHA1HashValidator {

    public SHA1HashResult validate(Path artifact, Path hash) {
        try {
            MessageDigest digest = MessageDigest.getInstance("SHA-1");
            InputStream artifactIS = Files.newInputStream(artifact);
            byte[] buff = new byte[4096];
            int read;
            while ((read = artifactIS.read(buff)) != -1) {
                digest.update(buff, 0, read);
            }
            byte[] hashed = digest.digest();
            String actualHash = Hex.toHexString(hashed);
            String expectedHash = Files.readString(hash, StandardCharsets.US_ASCII);
            return new SHA1HashResult(actualHash.equalsIgnoreCase(expectedHash), expectedHash, actualHash);
        } catch (NoSuchAlgorithmException | IOException e) {
            throw new IllegalStateException("Cannot validate SHA-1 hash.", e);
        }
    }

}