/*
 * 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 under the License.
 */
package org.apache.kafka.connect.util;

import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectStreamClass;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

public class SafeObjectInputStream extends ObjectInputStream {

    protected static final Set<String> DEFAULT_NO_DESERIALIZE_CLASS_NAMES;

    static {

        Set<String> s = new HashSet<>();
        s.add("org.apache.commons.collections.functors.InvokerTransformer");
        s.add("org.apache.commons.collections.functors.InstantiateTransformer");
        s.add("org.apache.commons.collections4.functors.InvokerTransformer");
        s.add("org.apache.commons.collections4.functors.InstantiateTransformer");
        s.add("org.codehaus.groovy.runtime.ConvertedClosure");
        s.add("org.codehaus.groovy.runtime.MethodClosure");
        s.add("org.springframework.beans.factory.ObjectFactory");
        s.add("com.sun.org.apache.xalan.internal.xsltc.trax.TemplatesImpl");
        s.add("org.apache.xalan.xsltc.trax.TemplatesImpl");
        DEFAULT_NO_DESERIALIZE_CLASS_NAMES = Collections.unmodifiableSet(s);
    }


    public SafeObjectInputStream(InputStream in) throws IOException {
        super(in);
    }

    @Override
    protected Class<?> resolveClass(ObjectStreamClass desc) throws IOException, ClassNotFoundException {
        String name = desc.getName();

        if (isBlocked(name)) {
            throw new SecurityException("Illegal type to deserialize: prevented for security reasons");
        }

        return super.resolveClass(desc);
    }

    private boolean isBlocked(String name) {
        for (String list : DEFAULT_NO_DESERIALIZE_CLASS_NAMES) {
            if (name.endsWith(list)) {
                return true;
            }
        }

        return false;
    }
}
