/*
* 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.sshd.server.auth;
import java.security.PublicKey;
import java.security.interfaces.RSAPublicKey;
import org.apache.sshd.common.KeyPairProvider;
import org.apache.sshd.common.NamedFactory;
import org.apache.sshd.common.Signature;
import org.apache.sshd.common.SshConstants;
import org.apache.sshd.common.SshException;
import org.apache.sshd.common.util.Buffer;
import org.apache.sshd.server.PublickeyAuthenticator;
import org.apache.sshd.server.UserAuth;
import org.apache.sshd.server.session.ServerSession;
/**
* TODO Add javadoc
*
* @author <a href="mailto:dev@mina.apache.org">Apache MINA SSHD Project</a>
*/
public class UserAuthPublicKey extends AbstractUserAuth {
public static class Factory implements NamedFactory<UserAuth> {
public String getName() {
return "publickey";
}
public UserAuth create() {
return new UserAuthPublicKey();
}
}
public Boolean doAuth(Buffer buffer, boolean init) throws Exception {
if (!init) {
throw new IllegalStateException();
}
if (!"ssh-connection".equals(service)) {
throw new SshException(SshConstants.SSH2_DISCONNECT_PROTOCOL_ERROR, "Unsupported service '" + service + "'");
}
boolean hasSig = buffer.getBoolean();
String alg = buffer.getString();
int oldLim = buffer.wpos();
int oldPos = buffer.rpos();
int len = buffer.getInt();
buffer.wpos(buffer.rpos() + len);
PublicKey key = buffer.getRawPublicKey();
String keyAlg = (key instanceof RSAPublicKey) ? KeyPairProvider.SSH_RSA : KeyPairProvider.SSH_DSS;
Signature verif = NamedFactory.Utils.create(session.getFactoryManager().getSignatureFactories(), keyAlg);
verif.init(key, null);
buffer.wpos(oldLim);
byte[] sig = hasSig ? buffer.getBytes() : null;
PublickeyAuthenticator authenticator = session.getServerFactoryManager().getPublickeyAuthenticator();
if (authenticator == null) {
throw new Exception("No PublickeyAuthenticator configured");
}
if (!authenticator.authenticate(username, key, session)) {
return false;
}
if (!hasSig) {
Buffer buf = session.createBuffer(SshConstants.Message.SSH_MSG_USERAUTH_PK_OK, 0);
buf.putString(alg);
buf.putRawBytes(buffer.array(), oldPos, 4 + len);
session.writePacket(buf);
return null;
} else {
Buffer buf = new Buffer();
buf.putString(session.getKex().getH());
buf.putCommand(SshConstants.Message.SSH_MSG_USERAUTH_REQUEST);
buf.putString(username);
buf.putString("ssh-connection");
buf.putString("publickey");
buf.putByte((byte) 1);
buf.putString(keyAlg);
buffer.rpos(oldPos);
buffer.wpos(oldPos + 4 + len);
buf.putBuffer(buffer);
verif.update(buf.array(), buf.rpos(), buf.available());
if (!verif.verify(sig)) {
throw new Exception("Key verification failed");
}
return true;
}
}
}