/*
* 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.common.kex;
import java.security.PublicKey;
import java.util.Collections;
import java.util.Map;
import org.apache.sshd.common.NamedResource;
import org.apache.sshd.common.SshConstants;
import org.apache.sshd.common.digest.Digest;
import org.apache.sshd.common.session.Session;
import org.apache.sshd.common.util.GenericUtils;
import org.apache.sshd.common.util.buffer.Buffer;
import org.apache.sshd.common.util.logging.LoggingUtils;
/**
* Key exchange algorithm.
*
* @author <a href="mailto:dev@mina.apache.org">Apache MINA SSHD Project</a>
*/
public interface KeyExchange extends NamedResource {
Map<Integer, String> GROUP_KEX_OPCODES_MAP =
Collections.unmodifiableMap(LoggingUtils.generateMnemonicMap(SshConstants.class, "SSH_MSG_KEX_DH_GEX_"));
Map<Integer, String> SIMPLE_KEX_OPCODES_MAP =
Collections.unmodifiableMap(LoggingUtils.generateMnemonicMap(SshConstants.class, "SSH_MSG_KEXDH_"));
/**
* Initialize the key exchange algorithm.
*
* @param session the session using this algorithm
* @param v_s the server identification string
* @param v_c the client identification string
* @param i_s the server key initialization packet
* @param i_c the client key initialization packet
* @throws Exception if an error occurs
*/
void init(Session session, byte[] v_s, byte[] v_c, byte[] i_s, byte[] i_c) throws Exception;
/**
* Process the next packet
*
* @param cmd the command
* @param buffer the packet contents positioned after the command
* @return a boolean indicating if the processing is complete or if more packets are to be received
* @throws Exception if an error occurs
*/
boolean next(int cmd, Buffer buffer) throws Exception;
/**
* The message digest used by this key exchange algorithm.
*
* @return the message digest
*/
Digest getHash();
/**
* Retrieves the computed {@code h} parameter
*
* @return The {@code h} parameter
*/
byte[] getH();
/**
* Retrieves the computed k parameter
*
* @return The {@code k} parameter
*/
byte[] getK();
/**
* Retrieves the server's key
*
* @return The server's {@link PublicKey}
*/
PublicKey getServerKey();
static String getGroupKexOpcodeName(int cmd) {
String name = GROUP_KEX_OPCODES_MAP.get(cmd);
if (GenericUtils.isEmpty(name)) {
return SshConstants.getCommandMessageName(cmd);
} else {
return name;
}
}
static String getSimpleKexOpcodeName(int cmd) {
String name = SIMPLE_KEX_OPCODES_MAP.get(cmd);
if (GenericUtils.isEmpty(name)) {
return SshConstants.getCommandMessageName(cmd);
} else {
return name;
}
}
}