org.apache.sshd.server.PublickeyAuthenticatorUtils.java Source code

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Here is the source code for org.apache.sshd.server.PublickeyAuthenticatorUtils.java

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/*
 * Copyright 2013 Lyor Goldstein
 * 
 * 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 org.apache.sshd.server;

import java.io.File;
import java.security.PublicKey;
import java.util.Arrays;
import java.util.Collection;
import java.util.Map;

import org.apache.commons.collections15.AbstractExtendedPredicate;
import org.apache.commons.collections15.CollectionUtils;
import org.apache.commons.collections15.ExtendedCollectionUtils;
import org.apache.commons.collections15.ExtendedMapUtils;
import org.apache.commons.lang3.ArrayUtils;
import org.apache.commons.net.ssh.keys.CryptoKeyEntry;
import org.apache.sshd.server.session.ServerSession;

/**
 * <P>Copyright as per GPLv2</P>
 * @author Lyor G.
 * @since Jul 2, 2013 3:20:47 PM
 */
public class PublickeyAuthenticatorUtils {
    /**
     * A {@link PublickeyAuthenticator} that accepts all authentication attempts
     */
    public static final PublickeyAuthenticator ACCEPT_ALL_AUTHENTICATOR = new PublickeyAuthenticator() {
        @Override
        public boolean authenticate(String username, PublicKey key, ServerSession session) {
            return true;
        }
    };

    /**
     * A {@link PublickeyAuthenticator} that rejects all authentication attempts
     */
    public static final PublickeyAuthenticator REJECT_ALL_AUTHENTICATOR = new PublickeyAuthenticator() {
        @Override
        public boolean authenticate(String username, PublicKey key, ServerSession session) {
            return false;
        }
    };

    /**
     * @param entries A {@link Collection} of {@link CryptoKeyEntry}-ies
     * @return A {@link PublickeyAuthenticator} that matches the received encoded
     * public key bytes to one of the authorized keys published by the user
     * @see CryptoKeyEntry#readAuthorizedKeys(File)
     */
    public static final PublickeyAuthenticator authorizedKeysAuthenticator(
            Collection<? extends CryptoKeyEntry> entries) {
        final Map<String, ? extends Collection<CryptoKeyEntry>> keysMap = ExtendedMapUtils.mapCollectionMultiValues(
                CryptoKeyEntry.USERNAME_EXTRACTOR, ExtendedCollectionUtils.<CryptoKeyEntry>linkedListFactory(),
                entries);
        return new PublickeyAuthenticator() {
            @Override
            public boolean authenticate(String username, PublicKey key, ServerSession session) {
                Collection<CryptoKeyEntry> keySet = keysMap.get(username);
                if (ExtendedCollectionUtils.isEmpty(keySet)) {
                    return false;
                }

                final byte[] keyBytes = key.getEncoded();
                if (ArrayUtils.isEmpty(keyBytes)) {
                    return false; // TODO consider throwing an exception
                }

                CryptoKeyEntry entry = CollectionUtils.find(keySet,
                        new AbstractExtendedPredicate<CryptoKeyEntry>(CryptoKeyEntry.class) {
                            @Override
                            public boolean evaluate(CryptoKeyEntry e) {
                                byte[] entryBytes = e.getKeyData();
                                if (Arrays.equals(keyBytes, entryBytes)) {
                                    return true;
                                } else {
                                    return false; // debug breakpoint;
                                }
                            }
                        });
                if (entry == null) {
                    return false;
                } else {
                    return true;
                }
            }
        };
    }
}