/*
    * Copyright (C) 2018, 2021 Thomas Wolf <thomas.wolf@paranor.ch> and others
    *
    * This program and the accompanying materials are made available under the
    * terms of the Eclipse Distribution License v. 1.0 which is available at
    * https://www.eclipse.org/org/documents/edl-v10.php.
    *
    * SPDX-License-Identifier: BSD-3-Clause
    */
  
  package org.eclipse.jgit.transport;
  
  import org.eclipse.jgit.lib.Constants;
  
  /**
   * Constants relating to ssh.
   *
   * @since 5.2
   */
  @SuppressWarnings("nls")
  public final class SshConstants {
  
  	private SshConstants() {
  		// No instances, please.
  	}
  
  	/** IANA assigned port number for ssh. */
  	public static final int SSH_DEFAULT_PORT = 22;
  
  	/** URI scheme for ssh. */
  	public static final String SSH_SCHEME = "ssh";
  
  	/** URI scheme for sftp. */
  	public static final String SFTP_SCHEME = "sftp";
  
  	/** Default name for a ssh directory. */
  	public static final String SSH_DIR = ".ssh";
  
  	/** Name of the ssh config file. */
  	public static final String CONFIG = Constants.CONFIG;
  
  	/** Default name of the user "known hosts" file. */
  	public static final String KNOWN_HOSTS = "known_hosts";
  
  	// Config file keys
  
  	/**
  	 * Property to control whether private keys are added to an SSH agent, if
  	 * one is running, after having been loaded.
  	 *
  	 * @since 6.1
  	 */
  	public static final String ADD_KEYS_TO_AGENT = "AddKeysToAgent";
  
  	/** Key in an ssh config file. */
  	public static final String BATCH_MODE = "BatchMode";
  
  	/** Key in an ssh config file. */
  	public static final String CANONICAL_DOMAINS = "CanonicalDomains";
  
  	/** Key in an ssh config file. */
  	public static final String CERTIFICATE_FILE = "CertificateFile";
  
  	/** Key in an ssh config file. */
  	public static final String CIPHERS = "Ciphers";
  
  	/** Key in an ssh config file. */
  	public static final String COMPRESSION = "Compression";
  
  	/** Key in an ssh config file. */
  	public static final String CONNECTION_ATTEMPTS = "ConnectionAttempts";
  
  	/**
  	 * An OpenSSH time value for the connection timeout. In OpenSSH, this
  	 * includes everything until the end of the initial key exchange; in JGit it
  	 * covers only the underlying TCP connect.
  	 *
  	 * @since 6.1
  	 */
  	public static final String CONNECT_TIMEOUT = "ConnectTimeout";
  
  	/** Key in an ssh config file. */
  	public static final String CONTROL_PATH = "ControlPath";
  
  	/** Key in an ssh config file. */
  	public static final String GLOBAL_KNOWN_HOSTS_FILE = "GlobalKnownHostsFile";
  
  	/**
  	 * Key in an ssh config file.
  	 *
  	 * @since 5.5
  	 */
  	public static final String HASH_KNOWN_HOSTS = "HashKnownHosts";
  
  	/** Key in an ssh config file. */
  	public static final String HOST = "Host";
  
  	/** Key in an ssh config file. */
  	public static final String HOST_KEY_ALGORITHMS = "HostKeyAlgorithms";
 
 	/** Key in an ssh config file. */
 	public static final String HOST_NAME = "HostName";
 
 	/** Key in an ssh config file. */
 	public static final String IDENTITIES_ONLY = "IdentitiesOnly";
 
 	/** Key in an ssh config file. */
 	public static final String IDENTITY_AGENT = "IdentityAgent";
 
 	/** Key in an ssh config file. */
 	public static final String IDENTITY_FILE = "IdentityFile";
 
 	/** Key in an ssh config file. */
 	public static final String KEX_ALGORITHMS = "KexAlgorithms";
 
 	/** Key in an ssh config file. */
 	public static final String LOCAL_COMMAND = "LocalCommand";
 
 	/** Key in an ssh config file. */
 	public static final String LOCAL_FORWARD = "LocalForward";
 
 	/** Key in an ssh config file. */
 	public static final String MACS = "MACs";
 
 	/** Key in an ssh config file. */
 	public static final String NUMBER_OF_PASSWORD_PROMPTS = "NumberOfPasswordPrompts";
 
 	/** Key in an ssh config file. */
 	public static final String PORT = "Port";
 
 	/** Key in an ssh config file. */
 	public static final String PREFERRED_AUTHENTICATIONS = "PreferredAuthentications";
 
 	/**
 	 * Key in an ssh config file; defines signature algorithms for public key
 	 * authentication as a comma-separated list.
 	 *
 	 * @since 5.11.1
 	 */
 	public static final String PUBKEY_ACCEPTED_ALGORITHMS = "PubkeyAcceptedAlgorithms";
 
 	/** Key in an ssh config file. */
 	public static final String PROXY_COMMAND = "ProxyCommand";
 
 	/**
 	 * Comma-separated list of jump hosts, defining a jump host chain <em>in
 	 * reverse order</em>. Each jump host is a SSH URI or "[user@]host[:port]".
 	 * <p>
 	 * Reverse order means: to connect A->B->target, one can do in
 	 * {@code ~/.ssh/config} either of:
 	 * </p>
 	 *
 	 * <pre>
 	 * Host target
 	 *   ProxyJump B,A
 	 * </pre>
 	 * <p>
 	 * <em>or</em>
 	 * </p>
 	 *
 	 * <pre>
 	 * Host target
 	 *   ProxyJump B
 	 *
 	 * Host B
 	 *   ProxyJump A
 	 * </pre>
 	 *
 	 * @since 5.10
 	 */
 	public static final String PROXY_JUMP = "ProxyJump";
 
 	/** Key in an ssh config file. */
 	public static final String REMOTE_COMMAND = "RemoteCommand";
 
 	/** Key in an ssh config file. */
 	public static final String REMOTE_FORWARD = "RemoteForward";
 
 	/**
 	 * (Absolute) path to a middleware library the SSH agent shall use to load
 	 * SK (U2F) keys.
 	 *
 	 * @since 6.1
 	 */
 	public static final String SECURITY_KEY_PROVIDER = "SecurityKeyProvider";
 
 	/** Key in an ssh config file. */
 	public static final String SEND_ENV = "SendEnv";
 
 	/** Key in an ssh config file. */
 	public static final String STRICT_HOST_KEY_CHECKING = "StrictHostKeyChecking";
 
 	/** Key in an ssh config file. */
 	public static final String USER = "User";
 
 	/** Key in an ssh config file. */
 	public static final String USER_KNOWN_HOSTS_FILE = "UserKnownHostsFile";
 
 	// Values
 
 	/** Flag value. */
 	public static final String YES = "yes";
 
 	/** Flag value. */
 	public static final String ON = "on";
 
 	/** Flag value. */
 	public static final String TRUE = "true";
 
 	/** Flag value. */
 	public static final String NO = "no";
 
 	/** Flag value. */
 	public static final String OFF = "off";
 
 	/** Flag value. */
 	public static final String FALSE = "false";
 
 	/**
 	 * Property value. Some keys accept a special 'none' value to override and
 	 * clear a setting otherwise contributed by another host entry, for instance
 	 * {@link #PROXY_COMMAND} or {@link #PROXY_JUMP}. Example:
 	 *
 	 * <pre>
 	 * Host bastion.example.org
 	 *   ProxyJump none
 	 *
 	 * Host *.example.org
 	 *   ProxyJump bastion.example.org
 	 * </pre>
 	 * <p>
 	 * OpenSSH supports this since OpenSSH 7.8.
 	 * </p>
 	 *
 	 * @since 6.0
 	 */
 	public static final String NONE = "none";
 
 	// Default identity file names
 
 	/** Name of the default RSA private identity file. */
 	public static final String ID_RSA = "id_rsa";
 
 	/** Name of the default DSA private identity file. */
 	public static final String ID_DSA = "id_dsa";
 
 	/** Name of the default ECDSA private identity file. */
 	public static final String ID_ECDSA = "id_ecdsa";
 
 	/** Name of the default ED25519 private identity file. */
 	public static final String ID_ED25519 = "id_ed25519";
 
 	/** All known default identity file names. */
 	public static final String[] DEFAULT_IDENTITIES = { //
 			ID_RSA, ID_DSA, ID_ECDSA, ID_ED25519
 	};
 
 	/**
 	 * Name of the environment variable holding the Unix domain socket for
 	 * communication with an SSH agent.
 	 *
 	 * @since 6.1
 	 */
 	public static final String ENV_SSH_AUTH_SOCKET = "SSH_AUTH_SOCK";
 }