org.apache.sshd.common.kex.KexProposalOption Maven / Gradle / Ivy
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* 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.util.Collections;
import java.util.Comparator;
import java.util.EnumSet;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;
import org.apache.sshd.common.util.GenericUtils;
/**
* @author Apache MINA SSHD Project
*/
public enum KexProposalOption {
ALGORITHMS(Constants.PROPOSAL_KEX_ALGS, "kex algorithms"),
SERVERKEYS(Constants.PROPOSAL_SERVER_HOST_KEY_ALGS, "server host key algorithms"),
C2SENC(Constants.PROPOSAL_ENC_ALGS_CTOS, "encryption algorithms (client to server)"),
S2CENC(Constants.PROPOSAL_ENC_ALGS_STOC, "encryption algorithms (server to client)"),
C2SMAC(Constants.PROPOSAL_MAC_ALGS_CTOS, "mac algorithms (client to server)"),
S2CMAC(Constants.PROPOSAL_MAC_ALGS_STOC, "mac algorithms (server to client)"),
C2SCOMP(Constants.PROPOSAL_COMP_ALGS_CTOS, "compression algorithms (client to server)"),
S2CCOMP(Constants.PROPOSAL_COMP_ALGS_STOC, "compression algorithms (server to client)"),
C2SLANG(Constants.PROPOSAL_LANG_CTOS, "languages (client to server)"),
S2CLANG(Constants.PROPOSAL_LANG_STOC, "languages (server to client)");
public static final Set CIPHER_PROPOSALS = Collections.unmodifiableSet(EnumSet.of(C2SENC, S2CENC));
public static final Set MAC_PROPOSALS = Collections.unmodifiableSet(EnumSet.of(C2SMAC, S2CMAC));
public static final Set COMPRESSION_PROPOSALS
= Collections.unmodifiableSet(EnumSet.of(C2SCOMP, S2CCOMP));
public static final Set LANGUAGE_PROPOSALS = Collections.unmodifiableSet(EnumSet.of(C2SLANG, S2CLANG));
public static final Set FIRST_KEX_PACKET_GUESS_MATCHES
= Collections.unmodifiableSet(EnumSet.of(ALGORITHMS, SERVERKEYS));
/**
* Compares values according to {@link KexProposalOption#getProposalIndex()}
*/
public static final Comparator BY_PROPOSAL_INDEX
= Comparator.comparingInt(KexProposalOption::getProposalIndex);
/**
* A {@link List} of all the options sorted according to {@link #getProposalIndex()}
*
* @see #BY_PROPOSAL_INDEX
*/
public static final List VALUES = Collections.unmodifiableList(
EnumSet.allOf(KexProposalOption.class)
.stream()
.sorted(BY_PROPOSAL_INDEX)
.collect(Collectors.toList()));
public static final int PROPOSAL_MAX = VALUES.size();
private final int proposalIndex;
private final String description;
KexProposalOption(int index, String desc) {
proposalIndex = index;
description = desc;
}
/**
* @return The proposal option location in the KEX array
*/
public final int getProposalIndex() {
return proposalIndex;
}
/**
* @return User-friendly name for the KEX negotiation item
* @see RFC-4253 - section 7.1
*/
public final String getDescription() {
return description;
}
/**
* @param n The option name - ignored if {@code null}/empty
* @return The matching {@link KexProposalOption#name()} - case insensitive or {@code null} if no match
* found
*/
public static KexProposalOption fromName(String n) {
if (GenericUtils.isEmpty(n)) {
return null;
}
for (KexProposalOption o : VALUES) {
if (n.equalsIgnoreCase(o.name())) {
return o;
}
}
return null;
}
public static KexProposalOption fromProposalIndex(int index) {
if ((index < 0) || (index >= VALUES.size())) {
return null;
} else {
return VALUES.get(index);
}
}
public static final class Constants {
public static final int PROPOSAL_KEX_ALGS = 0;
public static final int PROPOSAL_SERVER_HOST_KEY_ALGS = 1;
public static final int PROPOSAL_ENC_ALGS_CTOS = 2;
public static final int PROPOSAL_ENC_ALGS_STOC = 3;
public static final int PROPOSAL_MAC_ALGS_CTOS = 4;
public static final int PROPOSAL_MAC_ALGS_STOC = 5;
public static final int PROPOSAL_COMP_ALGS_CTOS = 6;
public static final int PROPOSAL_COMP_ALGS_STOC = 7;
public static final int PROPOSAL_LANG_CTOS = 8;
public static final int PROPOSAL_LANG_STOC = 9;
private Constants() {
throw new UnsupportedOperationException("No instance allowed");
}
}
}