--- /dev/null
+/*
+ * Copyright (c) 2006-2011 Christian Plattner. All rights reserved.
+ * Please refer to the LICENSE.txt for licensing details.
+ */
+
+package ch.ethz.ssh2;
+
+import java.io.CharArrayWriter;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.SocketTimeoutException;
+import java.security.SecureRandom;
+import java.util.List;
+import java.util.Vector;
+
+import ch.ethz.ssh2.auth.AuthenticationManager;
+import ch.ethz.ssh2.channel.ChannelManager;
+import ch.ethz.ssh2.crypto.CryptoWishList;
+import ch.ethz.ssh2.crypto.cipher.BlockCipherFactory;
+import ch.ethz.ssh2.crypto.digest.MAC;
+import ch.ethz.ssh2.packets.PacketIgnore;
+import ch.ethz.ssh2.transport.KexManager;
+import ch.ethz.ssh2.transport.TransportManager;
+import ch.ethz.ssh2.util.TimeoutService;
+import ch.ethz.ssh2.util.TimeoutService.TimeoutToken;
+
+/**
+ * A <code>Connection</code> is used to establish an encrypted TCP/IP
+ * connection to a SSH-2 server.
+ * <p>
+ * Typically, one
+ * <ol>
+ * <li>creates a {@link #Connection(String) Connection} object.</li>
+ * <li>calls the {@link #connect() connect()} method.</li>
+ * <li>calls some of the authentication methods (e.g., {@link #authenticateWithPublicKey(String, File, String) authenticateWithPublicKey()}).</li>
+ * <li>calls one or several times the {@link #openSession() openSession()} method.</li>
+ * <li>finally, one must close the connection and release resources with the {@link #close() close()} method.</li>
+ * </ol>
+ *
+ * @author Christian Plattner
+ * @version $Id: Connection.java 69 2013-08-09 06:39:56Z dkocher@sudo.ch $
+ */
+
+public class Connection
+{
+ /**
+ * The identifier presented to the SSH-2 server. This is the same
+ * as the "softwareversion" defined in RFC 4253.
+ * <p/>
+ * <b>NOTE: As per the RFC, the "softwareversion" string MUST consist of printable
+ * US-ASCII characters, with the exception of whitespace characters and the minus sign (-).</b>
+ */
+ private String softwareversion = String.format("Ganymed_%s", Version.getSpecification());
+
+ /* Will be used to generate all random data needed for the current connection.
+ * Note: SecureRandom.nextBytes() is thread safe.
+ */
+
+ private SecureRandom generator;
+
+ /**
+ * Unless you know what you are doing, you will never need this.
+ *
+ * @return The list of supported cipher algorithms by this implementation.
+ */
+ public static synchronized String[] getAvailableCiphers()
+ {
+ return BlockCipherFactory.getDefaultCipherList();
+ }
+
+ /**
+ * Unless you know what you are doing, you will never need this.
+ *
+ * @return The list of supported MAC algorthims by this implementation.
+ */
+ public static synchronized String[] getAvailableMACs()
+ {
+ return MAC.getMacList();
+ }
+
+ /**
+ * Unless you know what you are doing, you will never need this.
+ *
+ * @return The list of supported server host key algorthims by this implementation.
+ */
+ public static synchronized String[] getAvailableServerHostKeyAlgorithms()
+ {
+ return KexManager.getDefaultServerHostkeyAlgorithmList();
+ }
+
+ private AuthenticationManager am;
+
+ private boolean authenticated = false;
+ private ChannelManager cm;
+
+ private CryptoWishList cryptoWishList = new CryptoWishList();
+
+ private DHGexParameters dhgexpara = new DHGexParameters();
+
+ private final String hostname;
+
+ private final int port;
+
+ private TransportManager tm;
+
+ private boolean tcpNoDelay = false;
+
+ private ProxyData proxyData = null;
+
+ private List<ConnectionMonitor> connectionMonitors = new Vector<ConnectionMonitor>();
+
+ /**
+ * Prepares a fresh <code>Connection</code> object which can then be used
+ * to establish a connection to the specified SSH-2 server.
+ * <p>
+ * Same as {@link #Connection(String, int) Connection(hostname, 22)}.
+ *
+ * @param hostname the hostname of the SSH-2 server.
+ */
+ public Connection(String hostname)
+ {
+ this(hostname, 22);
+ }
+
+ /**
+ * Prepares a fresh <code>Connection</code> object which can then be used
+ * to establish a connection to the specified SSH-2 server.
+ *
+ * @param hostname
+ * the host where we later want to connect to.
+ * @param port
+ * port on the server, normally 22.
+ */
+ public Connection(String hostname, int port)
+ {
+ this.hostname = hostname;
+ this.port = port;
+ }
+
+ /**
+ * Prepares a fresh <code>Connection</code> object which can then be used
+ * to establish a connection to the specified SSH-2 server.
+ *
+ * @param hostname
+ * the host where we later want to connect to.
+ * @param port
+ * port on the server, normally 22.
+ * @param softwareversion
+ * Allows you to set a custom "softwareversion" string as defined in RFC 4253.
+ * <b>NOTE: As per the RFC, the "softwareversion" string MUST consist of printable
+ * US-ASCII characters, with the exception of whitespace characters and the minus sign (-).</b>
+ */
+ public Connection(String hostname, int port, String softwareversion)
+ {
+ this.hostname = hostname;
+ this.port = port;
+ this.softwareversion = softwareversion;
+ }
+
+ /**
+ * After a successful connect, one has to authenticate oneself. This method
+ * is based on DSA (it uses DSA to sign a challenge sent by the server).
+ * <p>
+ * If the authentication phase is complete, <code>true</code> will be
+ * returned. If the server does not accept the request (or if further
+ * authentication steps are needed), <code>false</code> is returned and
+ * one can retry either by using this or any other authentication method
+ * (use the <code>getRemainingAuthMethods</code> method to get a list of
+ * the remaining possible methods).
+ *
+ * @param user
+ * A <code>String</code> holding the username.
+ * @param pem
+ * A <code>String</code> containing the DSA private key of the
+ * user in OpenSSH key format (PEM, you can't miss the
+ * "-----BEGIN DSA PRIVATE KEY-----" tag). The string may contain
+ * linefeeds.
+ * @param password
+ * If the PEM string is 3DES encrypted ("DES-EDE3-CBC"), then you
+ * must specify the password. Otherwise, this argument will be
+ * ignored and can be set to <code>null</code>.
+ *
+ * @return whether the connection is now authenticated.
+ * @throws IOException
+ *
+ * @deprecated You should use one of the {@link #authenticateWithPublicKey(String, File, String) authenticateWithPublicKey()}
+ * methods, this method is just a wrapper for it and will
+ * disappear in future builds.
+ *
+ */
+ public synchronized boolean authenticateWithDSA(String user, String pem, String password) throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("Connection is not established!");
+
+ if (authenticated)
+ throw new IllegalStateException("Connection is already authenticated!");
+
+ if (am == null)
+ am = new AuthenticationManager(tm);
+
+ if (cm == null)
+ cm = new ChannelManager(tm);
+
+ if (user == null)
+ throw new IllegalArgumentException("user argument is null");
+
+ if (pem == null)
+ throw new IllegalArgumentException("pem argument is null");
+
+ authenticated = am.authenticatePublicKey(user, pem.toCharArray(), password, getOrCreateSecureRND());
+
+ return authenticated;
+ }
+
+ /**
+ * A wrapper that calls {@link #authenticateWithKeyboardInteractive(String, String[], InteractiveCallback)
+ * authenticateWithKeyboardInteractivewith} a <code>null</code> submethod list.
+ *
+ * @param user
+ * A <code>String</code> holding the username.
+ * @param cb
+ * An <code>InteractiveCallback</code> which will be used to
+ * determine the responses to the questions asked by the server.
+ * @return whether the connection is now authenticated.
+ * @throws IOException
+ */
+ public synchronized boolean authenticateWithKeyboardInteractive(String user, InteractiveCallback cb)
+ throws IOException
+ {
+ return authenticateWithKeyboardInteractive(user, null, cb);
+ }
+
+ /**
+ * After a successful connect, one has to authenticate oneself. This method
+ * is based on "keyboard-interactive", specified in
+ * draft-ietf-secsh-auth-kbdinteract-XX. Basically, you have to define a
+ * callback object which will be feeded with challenges generated by the
+ * server. Answers are then sent back to the server. It is possible that the
+ * callback will be called several times during the invocation of this
+ * method (e.g., if the server replies to the callback's answer(s) with
+ * another challenge...)
+ * <p>
+ * If the authentication phase is complete, <code>true</code> will be
+ * returned. If the server does not accept the request (or if further
+ * authentication steps are needed), <code>false</code> is returned and
+ * one can retry either by using this or any other authentication method
+ * (use the <code>getRemainingAuthMethods</code> method to get a list of
+ * the remaining possible methods).
+ * <p>
+ * Note: some SSH servers advertise "keyboard-interactive", however, any
+ * interactive request will be denied (without having sent any challenge to
+ * the client).
+ *
+ * @param user
+ * A <code>String</code> holding the username.
+ * @param submethods
+ * An array of submethod names, see
+ * draft-ietf-secsh-auth-kbdinteract-XX. May be <code>null</code>
+ * to indicate an empty list.
+ * @param cb
+ * An <code>InteractiveCallback</code> which will be used to
+ * determine the responses to the questions asked by the server.
+ *
+ * @return whether the connection is now authenticated.
+ * @throws IOException
+ */
+ public synchronized boolean authenticateWithKeyboardInteractive(String user, String[] submethods,
+ InteractiveCallback cb) throws IOException
+ {
+ if (cb == null)
+ throw new IllegalArgumentException("Callback may not ne NULL!");
+
+ if (tm == null)
+ throw new IllegalStateException("Connection is not established!");
+
+ if (authenticated)
+ throw new IllegalStateException("Connection is already authenticated!");
+
+ if (am == null)
+ am = new AuthenticationManager(tm);
+
+ if (cm == null)
+ cm = new ChannelManager(tm);
+
+ if (user == null)
+ throw new IllegalArgumentException("user argument is null");
+
+ authenticated = am.authenticateInteractive(user, submethods, cb);
+
+ return authenticated;
+ }
+
+ /**
+ * After a successful connect, one has to authenticate oneself. This method
+ * sends username and password to the server.
+ * <p>
+ * If the authentication phase is complete, <code>true</code> will be
+ * returned. If the server does not accept the request (or if further
+ * authentication steps are needed), <code>false</code> is returned and
+ * one can retry either by using this or any other authentication method
+ * (use the <code>getRemainingAuthMethods</code> method to get a list of
+ * the remaining possible methods).
+ * <p>
+ * Note: if this method fails, then please double-check that it is actually
+ * offered by the server (use {@link #getRemainingAuthMethods(String) getRemainingAuthMethods()}.
+ * <p>
+ * Often, password authentication is disabled, but users are not aware of it.
+ * Many servers only offer "publickey" and "keyboard-interactive". However,
+ * even though "keyboard-interactive" *feels* like password authentication
+ * (e.g., when using the putty or openssh clients) it is *not* the same mechanism.
+ *
+ * @param user
+ * @param password
+ * @return if the connection is now authenticated.
+ * @throws IOException
+ */
+ public synchronized boolean authenticateWithPassword(String user, String password) throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("Connection is not established!");
+
+ if (authenticated)
+ throw new IllegalStateException("Connection is already authenticated!");
+
+ if (am == null)
+ am = new AuthenticationManager(tm);
+
+ if (cm == null)
+ cm = new ChannelManager(tm);
+
+ if (user == null)
+ throw new IllegalArgumentException("user argument is null");
+
+ if (password == null)
+ throw new IllegalArgumentException("password argument is null");
+
+ authenticated = am.authenticatePassword(user, password);
+
+ return authenticated;
+ }
+
+ /**
+ * After a successful connect, one has to authenticate oneself.
+ * This method can be used to explicitly use the special "none"
+ * authentication method (where only a username has to be specified).
+ * <p>
+ * Note 1: The "none" method may always be tried by clients, however as by
+ * the specs, the server will not explicitly announce it. In other words,
+ * the "none" token will never show up in the list returned by
+ * {@link #getRemainingAuthMethods(String)}.
+ * <p>
+ * Note 2: no matter which one of the authenticateWithXXX() methods
+ * you call, the library will always issue exactly one initial "none"
+ * authentication request to retrieve the initially allowed list of
+ * authentication methods by the server. Please read RFC 4252 for the
+ * details.
+ * <p>
+ * If the authentication phase is complete, <code>true</code> will be
+ * returned. If further authentication steps are needed, <code>false</code>
+ * is returned and one can retry by any other authentication method
+ * (use the <code>getRemainingAuthMethods</code> method to get a list of
+ * the remaining possible methods).
+ *
+ * @param user
+ * @return if the connection is now authenticated.
+ * @throws IOException
+ */
+ public synchronized boolean authenticateWithNone(String user) throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("Connection is not established!");
+
+ if (authenticated)
+ throw new IllegalStateException("Connection is already authenticated!");
+
+ if (am == null)
+ am = new AuthenticationManager(tm);
+
+ if (cm == null)
+ cm = new ChannelManager(tm);
+
+ if (user == null)
+ throw new IllegalArgumentException("user argument is null");
+
+ /* Trigger the sending of the PacketUserauthRequestNone packet */
+ /* (if not already done) */
+
+ authenticated = am.authenticateNone(user);
+
+ return authenticated;
+ }
+
+ /**
+ * After a successful connect, one has to authenticate oneself.
+ * The authentication method "publickey" works by signing a challenge
+ * sent by the server. The signature is either DSA or RSA based - it
+ * just depends on the type of private key you specify, either a DSA
+ * or RSA private key in PEM format. And yes, this is may seem to be a
+ * little confusing, the method is called "publickey" in the SSH-2 protocol
+ * specification, however since we need to generate a signature, you
+ * actually have to supply a private key =).
+ * <p>
+ * The private key contained in the PEM file may also be encrypted ("Proc-Type: 4,ENCRYPTED").
+ * The library supports DES-CBC and DES-EDE3-CBC encryption, as well
+ * as the more exotic PEM encrpytions AES-128-CBC, AES-192-CBC and AES-256-CBC.
+ * <p>
+ * If the authentication phase is complete, <code>true</code> will be
+ * returned. If the server does not accept the request (or if further
+ * authentication steps are needed), <code>false</code> is returned and
+ * one can retry either by using this or any other authentication method
+ * (use the <code>getRemainingAuthMethods</code> method to get a list of
+ * the remaining possible methods).
+ * <p>
+ * NOTE PUTTY USERS: Event though your key file may start with "-----BEGIN..."
+ * it is not in the expected format. You have to convert it to the OpenSSH
+ * key format by using the "puttygen" tool (can be downloaded from the Putty
+ * website). Simply load your key and then use the "Conversions/Export OpenSSH key"
+ * functionality to get a proper PEM file.
+ *
+ * @param user
+ * A <code>String</code> holding the username.
+ * @param pemPrivateKey
+ * A <code>char[]</code> containing a DSA or RSA private key of the
+ * user in OpenSSH key format (PEM, you can't miss the
+ * "-----BEGIN DSA PRIVATE KEY-----" or "-----BEGIN RSA PRIVATE KEY-----"
+ * tag). The char array may contain linebreaks/linefeeds.
+ * @param password
+ * If the PEM structure is encrypted ("Proc-Type: 4,ENCRYPTED") then
+ * you must specify a password. Otherwise, this argument will be ignored
+ * and can be set to <code>null</code>.
+ *
+ * @return whether the connection is now authenticated.
+ * @throws IOException
+ */
+ public synchronized boolean authenticateWithPublicKey(String user, char[] pemPrivateKey, String password)
+ throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("Connection is not established!");
+
+ if (authenticated)
+ throw new IllegalStateException("Connection is already authenticated!");
+
+ if (am == null)
+ am = new AuthenticationManager(tm);
+
+ if (cm == null)
+ cm = new ChannelManager(tm);
+
+ if (user == null)
+ throw new IllegalArgumentException("user argument is null");
+
+ if (pemPrivateKey == null)
+ throw new IllegalArgumentException("pemPrivateKey argument is null");
+
+ authenticated = am.authenticatePublicKey(user, pemPrivateKey, password, getOrCreateSecureRND());
+
+ return authenticated;
+ }
+
+ /**
+ * A convenience wrapper function which reads in a private key (PEM format, either DSA or RSA)
+ * and then calls <code>authenticateWithPublicKey(String, char[], String)</code>.
+ * <p>
+ * NOTE PUTTY USERS: Event though your key file may start with "-----BEGIN..."
+ * it is not in the expected format. You have to convert it to the OpenSSH
+ * key format by using the "puttygen" tool (can be downloaded from the Putty
+ * website). Simply load your key and then use the "Conversions/Export OpenSSH key"
+ * functionality to get a proper PEM file.
+ *
+ * @param user
+ * A <code>String</code> holding the username.
+ * @param pemFile
+ * A <code>File</code> object pointing to a file containing a DSA or RSA
+ * private key of the user in OpenSSH key format (PEM, you can't miss the
+ * "-----BEGIN DSA PRIVATE KEY-----" or "-----BEGIN RSA PRIVATE KEY-----"
+ * tag).
+ * @param password
+ * If the PEM file is encrypted then you must specify the password.
+ * Otherwise, this argument will be ignored and can be set to <code>null</code>.
+ *
+ * @return whether the connection is now authenticated.
+ * @throws IOException
+ */
+ public synchronized boolean authenticateWithPublicKey(String user, File pemFile, String password)
+ throws IOException
+ {
+ if (pemFile == null)
+ throw new IllegalArgumentException("pemFile argument is null");
+
+ char[] buff = new char[256];
+
+ CharArrayWriter cw = new CharArrayWriter();
+
+ FileReader fr = new FileReader(pemFile);
+
+ while (true)
+ {
+ int len = fr.read(buff);
+ if (len < 0)
+ break;
+ cw.write(buff, 0, len);
+ }
+
+ fr.close();
+
+ return authenticateWithPublicKey(user, cw.toCharArray(), password);
+ }
+
+ /**
+ * Add a {@link ConnectionMonitor} to this connection. Can be invoked at any time,
+ * but it is best to add connection monitors before invoking
+ * <code>connect()</code> to avoid glitches (e.g., you add a connection monitor after
+ * a successful connect(), but the connection has died in the mean time. Then,
+ * your connection monitor won't be notified.)
+ * <p>
+ * You can add as many monitors as you like. If a monitor has already been added, then
+ * this method does nothing.
+ *
+ * @see ConnectionMonitor
+ *
+ * @param cmon An object implementing the {@link ConnectionMonitor} interface.
+ */
+ public synchronized void addConnectionMonitor(ConnectionMonitor cmon)
+ {
+ if (cmon == null)
+ throw new IllegalArgumentException("cmon argument is null");
+
+ if (!connectionMonitors.contains(cmon))
+ {
+ connectionMonitors.add(cmon);
+
+ if (tm != null)
+ tm.setConnectionMonitors(connectionMonitors);
+ }
+ }
+
+ /**
+ * Remove a {@link ConnectionMonitor} from this connection.
+ *
+ * @param cmon
+ * @return whether the monitor could be removed
+ */
+ public synchronized boolean removeConnectionMonitor(ConnectionMonitor cmon)
+ {
+ if (cmon == null)
+ throw new IllegalArgumentException("cmon argument is null");
+
+ boolean existed = connectionMonitors.remove(cmon);
+
+ if (tm != null)
+ tm.setConnectionMonitors(connectionMonitors);
+
+ return existed;
+ }
+
+ /**
+ * Close the connection to the SSH-2 server. All assigned sessions will be
+ * closed, too. Can be called at any time. Don't forget to call this once
+ * you don't need a connection anymore - otherwise the receiver thread may
+ * run forever.
+ */
+ public synchronized void close()
+ {
+ Throwable t = new Throwable("Closed due to user request.");
+ close(t, false);
+ }
+
+ public synchronized void close(Throwable t, boolean hard)
+ {
+ if (cm != null)
+ cm.closeAllChannels();
+
+ if (tm != null)
+ {
+ tm.close(t, hard == false);
+ tm = null;
+ }
+ am = null;
+ cm = null;
+ authenticated = false;
+ }
+
+ /**
+ * Same as {@link #connect(ServerHostKeyVerifier, int, int) connect(null, 0, 0)}.
+ *
+ * @return see comments for the {@link #connect(ServerHostKeyVerifier, int, int) connect(ServerHostKeyVerifier, int, int)} method.
+ * @throws IOException
+ */
+ public synchronized ConnectionInfo connect() throws IOException
+ {
+ return connect(null, 0, 0);
+ }
+
+ /**
+ * Same as {@link #connect(ServerHostKeyVerifier, int, int) connect(verifier, 0, 0)}.
+ *
+ * @return see comments for the {@link #connect(ServerHostKeyVerifier, int, int) connect(ServerHostKeyVerifier, int, int)} method.
+ * @throws IOException
+ */
+ public synchronized ConnectionInfo connect(ServerHostKeyVerifier verifier) throws IOException
+ {
+ return connect(verifier, 0, 0);
+ }
+
+ /**
+ * Connect to the SSH-2 server and, as soon as the server has presented its
+ * host key, use the {@link ServerHostKeyVerifier#verifyServerHostKey(String,
+ * int, String, byte[]) ServerHostKeyVerifier.verifyServerHostKey()}
+ * method of the <code>verifier</code> to ask for permission to proceed.
+ * If <code>verifier</code> is <code>null</code>, then any host key will be
+ * accepted - this is NOT recommended, since it makes man-in-the-middle attackes
+ * VERY easy (somebody could put a proxy SSH server between you and the real server).
+ * <p>
+ * Note: The verifier will be called before doing any crypto calculations
+ * (i.e., diffie-hellman). Therefore, if you don't like the presented host key then
+ * no CPU cycles are wasted (and the evil server has less information about us).
+ * <p>
+ * However, it is still possible that the server presented a fake host key: the server
+ * cheated (typically a sign for a man-in-the-middle attack) and is not able to generate
+ * a signature that matches its host key. Don't worry, the library will detect such
+ * a scenario later when checking the signature (the signature cannot be checked before
+ * having completed the diffie-hellman exchange).
+ * <p>
+ * Note 2: The {@link ServerHostKeyVerifier#verifyServerHostKey(String,
+ * int, String, byte[]) ServerHostKeyVerifier.verifyServerHostKey()} method
+ * will *NOT* be called from the current thread, the call is being made from a
+ * background thread (there is a background dispatcher thread for every
+ * established connection).
+ * <p>
+ * Note 3: This method will block as long as the key exchange of the underlying connection
+ * has not been completed (and you have not specified any timeouts).
+ * <p>
+ * Note 4: If you want to re-use a connection object that was successfully connected,
+ * then you must call the {@link #close()} method before invoking <code>connect()</code> again.
+ *
+ * @param verifier
+ * An object that implements the
+ * {@link ServerHostKeyVerifier} interface. Pass <code>null</code>
+ * to accept any server host key - NOT recommended.
+ *
+ * @param connectTimeout
+ * Connect the underlying TCP socket to the server with the given timeout
+ * value (non-negative, in milliseconds). Zero means no timeout. If a proxy is being
+ * used (see {@link #setProxyData(ProxyData)}), then this timeout is used for the
+ * connection establishment to the proxy.
+ *
+ * @param kexTimeout
+ * Timeout for complete connection establishment (non-negative,
+ * in milliseconds). Zero means no timeout. The timeout counts from the
+ * moment you invoke the connect() method and is cancelled as soon as the
+ * first key-exchange round has finished. It is possible that
+ * the timeout event will be fired during the invocation of the
+ * <code>verifier</code> callback, but it will only have an effect after
+ * the <code>verifier</code> returns.
+ *
+ * @return A {@link ConnectionInfo} object containing the details of
+ * the established connection.
+ *
+ * @throws IOException
+ * If any problem occurs, e.g., the server's host key is not
+ * accepted by the <code>verifier</code> or there is problem during
+ * the initial crypto setup (e.g., the signature sent by the server is wrong).
+ * <p>
+ * In case of a timeout (either connectTimeout or kexTimeout)
+ * a SocketTimeoutException is thrown.
+ * <p>
+ * An exception may also be thrown if the connection was already successfully
+ * connected (no matter if the connection broke in the mean time) and you invoke
+ * <code>connect()</code> again without having called {@link #close()} first.
+ * <p>
+ * If a HTTP proxy is being used and the proxy refuses the connection,
+ * then a {@link HTTPProxyException} may be thrown, which
+ * contains the details returned by the proxy. If the proxy is buggy and does
+ * not return a proper HTTP response, then a normal IOException is thrown instead.
+ */
+ public synchronized ConnectionInfo connect(ServerHostKeyVerifier verifier, int connectTimeout, int kexTimeout)
+ throws IOException
+ {
+ final class TimeoutState
+ {
+ boolean isCancelled = false;
+ boolean timeoutSocketClosed = false;
+ }
+
+ if (tm != null)
+ throw new IOException("Connection to " + hostname + " is already in connected state!");
+
+ if (connectTimeout < 0)
+ throw new IllegalArgumentException("connectTimeout must be non-negative!");
+
+ if (kexTimeout < 0)
+ throw new IllegalArgumentException("kexTimeout must be non-negative!");
+
+ final TimeoutState state = new TimeoutState();
+
+ tm = new TransportManager();
+ tm.setSoTimeout(connectTimeout);
+ tm.setConnectionMonitors(connectionMonitors);
+
+ /* Make sure that the runnable below will observe the new value of "tm"
+ * and "state" (the runnable will be executed in a different thread, which
+ * may be already running, that is why we need a memory barrier here).
+ * See also the comment in Channel.java if you
+ * are interested in the details.
+ *
+ * OKOK, this is paranoid since adding the runnable to the todo list
+ * of the TimeoutService will ensure that all writes have been flushed
+ * before the Runnable reads anything
+ * (there is a synchronized block in TimeoutService.addTimeoutHandler).
+ */
+
+ synchronized (tm)
+ {
+ /* We could actually synchronize on anything. */
+ }
+
+ try
+ {
+ TimeoutToken token = null;
+
+ if (kexTimeout > 0)
+ {
+ final Runnable timeoutHandler = new Runnable()
+ {
+ public void run()
+ {
+ synchronized (state)
+ {
+ if (state.isCancelled)
+ return;
+ state.timeoutSocketClosed = true;
+ tm.close(new SocketTimeoutException("The connect timeout expired"), false);
+ }
+ }
+ };
+
+ long timeoutHorizont = System.currentTimeMillis() + kexTimeout;
+
+ token = TimeoutService.addTimeoutHandler(timeoutHorizont, timeoutHandler);
+ }
+
+ try
+ {
+ tm.clientInit(hostname, port, softwareversion, cryptoWishList, verifier, dhgexpara, connectTimeout,
+ getOrCreateSecureRND(), proxyData);
+ }
+ catch (SocketTimeoutException se)
+ {
+ throw (SocketTimeoutException) new SocketTimeoutException(
+ "The connect() operation on the socket timed out.").initCause(se);
+ }
+
+ tm.setTcpNoDelay(tcpNoDelay);
+
+ /* Wait until first KEX has finished */
+
+ ConnectionInfo ci = tm.getConnectionInfo(1);
+
+ /* Now try to cancel the timeout, if needed */
+
+ if (token != null)
+ {
+ TimeoutService.cancelTimeoutHandler(token);
+
+ /* Were we too late? */
+
+ synchronized (state)
+ {
+ if (state.timeoutSocketClosed)
+ throw new IOException("This exception will be replaced by the one below =)");
+ /* Just in case the "cancelTimeoutHandler" invocation came just a little bit
+ * too late but the handler did not enter the semaphore yet - we can
+ * still stop it.
+ */
+ state.isCancelled = true;
+ }
+ }
+
+ return ci;
+ }
+ catch (SocketTimeoutException ste)
+ {
+ throw ste;
+ }
+ catch (IOException e1)
+ {
+ /* This will also invoke any registered connection monitors */
+ close(new Throwable("There was a problem during connect."), false);
+
+ synchronized (state)
+ {
+ /* Show a clean exception, not something like "the socket is closed!?!" */
+ if (state.timeoutSocketClosed)
+ throw new SocketTimeoutException("The kexTimeout (" + kexTimeout + " ms) expired.");
+ }
+
+ /* Do not wrap a HTTPProxyException */
+ if (e1 instanceof HTTPProxyException)
+ throw e1;
+
+ throw (IOException) new IOException("There was a problem while connecting to " + hostname + ":" + port)
+ .initCause(e1);
+ }
+ }
+
+ /**
+ * Creates a new {@link LocalPortForwarder}.
+ * A <code>LocalPortForwarder</code> forwards TCP/IP connections that arrive at a local
+ * port via the secure tunnel to another host (which may or may not be
+ * identical to the remote SSH-2 server).
+ * <p>
+ * This method must only be called after one has passed successfully the authentication step.
+ * There is no limit on the number of concurrent forwardings.
+ *
+ * @param local_port the local port the LocalPortForwarder shall bind to.
+ * @param host_to_connect target address (IP or hostname)
+ * @param port_to_connect target port
+ * @return A {@link LocalPortForwarder} object.
+ * @throws IOException
+ */
+ public synchronized LocalPortForwarder createLocalPortForwarder(int local_port, String host_to_connect,
+ int port_to_connect) throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("Cannot forward ports, you need to establish a connection first.");
+
+ if (!authenticated)
+ throw new IllegalStateException("Cannot forward ports, connection is not authenticated.");
+
+ return new LocalPortForwarder(cm, local_port, host_to_connect, port_to_connect);
+ }
+
+ /**
+ * Creates a new {@link LocalPortForwarder}.
+ * A <code>LocalPortForwarder</code> forwards TCP/IP connections that arrive at a local
+ * port via the secure tunnel to another host (which may or may not be
+ * identical to the remote SSH-2 server).
+ * <p>
+ * This method must only be called after one has passed successfully the authentication step.
+ * There is no limit on the number of concurrent forwardings.
+ *
+ * @param addr specifies the InetSocketAddress where the local socket shall be bound to.
+ * @param host_to_connect target address (IP or hostname)
+ * @param port_to_connect target port
+ * @return A {@link LocalPortForwarder} object.
+ * @throws IOException
+ */
+ public synchronized LocalPortForwarder createLocalPortForwarder(InetSocketAddress addr, String host_to_connect,
+ int port_to_connect) throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("Cannot forward ports, you need to establish a connection first.");
+
+ if (!authenticated)
+ throw new IllegalStateException("Cannot forward ports, connection is not authenticated.");
+
+ return new LocalPortForwarder(cm, addr, host_to_connect, port_to_connect);
+ }
+
+ /**
+ * Creates a new {@link LocalStreamForwarder}.
+ * A <code>LocalStreamForwarder</code> manages an Input/Outputstream pair
+ * that is being forwarded via the secure tunnel into a TCP/IP connection to another host
+ * (which may or may not be identical to the remote SSH-2 server).
+ *
+ * @param host_to_connect
+ * @param port_to_connect
+ * @return A {@link LocalStreamForwarder} object.
+ * @throws IOException
+ */
+ public synchronized LocalStreamForwarder createLocalStreamForwarder(String host_to_connect, int port_to_connect)
+ throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("Cannot forward, you need to establish a connection first.");
+
+ if (!authenticated)
+ throw new IllegalStateException("Cannot forward, connection is not authenticated.");
+
+ return new LocalStreamForwarder(cm, host_to_connect, port_to_connect);
+ }
+
+ /**
+ * Create a very basic {@link SCPClient} that can be used to copy
+ * files from/to the SSH-2 server.
+ * <p>
+ * Works only after one has passed successfully the authentication step.
+ * There is no limit on the number of concurrent SCP clients.
+ * <p>
+ * Note: This factory method will probably disappear in the future.
+ *
+ * @return A {@link SCPClient} object.
+ * @throws IOException
+ */
+ public synchronized SCPClient createSCPClient() throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("Cannot create SCP client, you need to establish a connection first.");
+
+ if (!authenticated)
+ throw new IllegalStateException("Cannot create SCP client, connection is not authenticated.");
+
+ return new SCPClient(this);
+ }
+
+ /**
+ * Force an asynchronous key re-exchange (the call does not block). The
+ * latest values set for MAC, Cipher and DH group exchange parameters will
+ * be used. If a key exchange is currently in progress, then this method has
+ * the only effect that the so far specified parameters will be used for the
+ * next (server driven) key exchange.
+ * <p>
+ * Note: This implementation will never start a key exchange (other than the initial one)
+ * unless you or the SSH-2 server ask for it.
+ *
+ * @throws IOException
+ * In case of any failure behind the scenes.
+ */
+ public synchronized void forceKeyExchange() throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("You need to establish a connection first.");
+
+ tm.forceKeyExchange(cryptoWishList, dhgexpara, null, null);
+ }
+
+ /**
+ * Returns the hostname that was passed to the constructor.
+ *
+ * @return the hostname
+ */
+ public synchronized String getHostname()
+ {
+ return hostname;
+ }
+
+ /**
+ * Returns the port that was passed to the constructor.
+ *
+ * @return the TCP port
+ */
+ public synchronized int getPort()
+ {
+ return port;
+ }
+
+ /**
+ * Returns a {@link ConnectionInfo} object containing the details of
+ * the connection. Can be called as soon as the connection has been
+ * established (successfully connected).
+ *
+ * @return A {@link ConnectionInfo} object.
+ * @throws IOException
+ * In case of any failure behind the scenes.
+ */
+ public synchronized ConnectionInfo getConnectionInfo() throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException(
+ "Cannot get details of connection, you need to establish a connection first.");
+ return tm.getConnectionInfo(1);
+ }
+
+ /**
+ * After a successful connect, one has to authenticate oneself. This method
+ * can be used to tell which authentication methods are supported by the
+ * server at a certain stage of the authentication process (for the given
+ * username).
+ * <p>
+ * Note 1: the username will only be used if no authentication step was done
+ * so far (it will be used to ask the server for a list of possible
+ * authentication methods by sending the initial "none" request). Otherwise,
+ * this method ignores the user name and returns a cached method list
+ * (which is based on the information contained in the last negative server response).
+ * <p>
+ * Note 2: the server may return method names that are not supported by this
+ * implementation.
+ * <p>
+ * After a successful authentication, this method must not be called
+ * anymore.
+ *
+ * @param user
+ * A <code>String</code> holding the username.
+ *
+ * @return a (possibly emtpy) array holding authentication method names.
+ * @throws IOException
+ */
+ public synchronized String[] getRemainingAuthMethods(String user) throws IOException
+ {
+ if (user == null)
+ throw new IllegalArgumentException("user argument may not be NULL!");
+
+ if (tm == null)
+ throw new IllegalStateException("Connection is not established!");
+
+ if (authenticated)
+ throw new IllegalStateException("Connection is already authenticated!");
+
+ if (am == null)
+ am = new AuthenticationManager(tm);
+
+ if (cm == null)
+ cm = new ChannelManager(tm);
+
+ return am.getRemainingMethods(user);
+ }
+
+ /**
+ * Determines if the authentication phase is complete. Can be called at any
+ * time.
+ *
+ * @return <code>true</code> if no further authentication steps are
+ * needed.
+ */
+ public synchronized boolean isAuthenticationComplete()
+ {
+ return authenticated;
+ }
+
+ /**
+ * Returns true if there was at least one failed authentication request and
+ * the last failed authentication request was marked with "partial success"
+ * by the server. This is only needed in the rare case of SSH-2 server setups
+ * that cannot be satisfied with a single successful authentication request
+ * (i.e., multiple authentication steps are needed.)
+ * <p>
+ * If you are interested in the details, then have a look at RFC4252.
+ *
+ * @return if the there was a failed authentication step and the last one
+ * was marked as a "partial success".
+ */
+ public synchronized boolean isAuthenticationPartialSuccess()
+ {
+ if (am == null)
+ return false;
+
+ return am.getPartialSuccess();
+ }
+
+ /**
+ * Checks if a specified authentication method is available. This method is
+ * actually just a wrapper for {@link #getRemainingAuthMethods(String)
+ * getRemainingAuthMethods()}.
+ *
+ * @param user
+ * A <code>String</code> holding the username.
+ * @param method
+ * An authentication method name (e.g., "publickey", "password",
+ * "keyboard-interactive") as specified by the SSH-2 standard.
+ * @return if the specified authentication method is currently available.
+ * @throws IOException
+ */
+ public synchronized boolean isAuthMethodAvailable(String user, String method) throws IOException
+ {
+ if (method == null)
+ throw new IllegalArgumentException("method argument may not be NULL!");
+
+ String methods[] = getRemainingAuthMethods(user);
+
+ for (int i = 0; i < methods.length; i++)
+ {
+ if (methods[i].compareTo(method) == 0)
+ return true;
+ }
+
+ return false;
+ }
+
+ private SecureRandom getOrCreateSecureRND()
+ {
+ if (generator == null)
+ generator = new SecureRandom();
+
+ return generator;
+ }
+
+ /**
+ * Open a new {@link Session} on this connection. Works only after one has passed
+ * successfully the authentication step. There is no limit on the number of
+ * concurrent sessions.
+ *
+ * @return A {@link Session} object.
+ * @throws IOException
+ */
+ public synchronized Session openSession() throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("Cannot open session, you need to establish a connection first.");
+
+ if (!authenticated)
+ throw new IllegalStateException("Cannot open session, connection is not authenticated.");
+
+ return new Session(cm, getOrCreateSecureRND());
+ }
+
+ /**
+ * Send an SSH_MSG_IGNORE packet. This method will generate a random data attribute
+ * (length between 0 (invlusive) and 16 (exclusive) bytes, contents are random bytes).
+ * <p>
+ * This method must only be called once the connection is established.
+ *
+ * @throws IOException
+ */
+ public synchronized void sendIgnorePacket() throws IOException
+ {
+ SecureRandom rnd = getOrCreateSecureRND();
+
+ byte[] data = new byte[rnd.nextInt(16)];
+ rnd.nextBytes(data);
+
+ sendIgnorePacket(data);
+ }
+
+ /**
+ * Send an SSH_MSG_IGNORE packet with the given data attribute.
+ * <p>
+ * This method must only be called once the connection is established.
+ *
+ * @throws IOException
+ */
+ public synchronized void sendIgnorePacket(byte[] data) throws IOException
+ {
+ if (data == null)
+ throw new IllegalArgumentException("data argument must not be null.");
+
+ if (tm == null)
+ throw new IllegalStateException(
+ "Cannot send SSH_MSG_IGNORE packet, you need to establish a connection first.");
+
+ PacketIgnore pi = new PacketIgnore();
+ pi.setData(data);
+
+ tm.sendMessage(pi.getPayload());
+ }
+
+ /**
+ * Removes duplicates from a String array, keeps only first occurence
+ * of each element. Does not destroy order of elements; can handle nulls.
+ * Uses a very efficient O(N^2) algorithm =)
+ *
+ * @param list a String array.
+ * @return a cleaned String array.
+ */
+ private String[] removeDuplicates(String[] list)
+ {
+ if ((list == null) || (list.length < 2))
+ return list;
+
+ String[] list2 = new String[list.length];
+
+ int count = 0;
+
+ for (int i = 0; i < list.length; i++)
+ {
+ boolean duplicate = false;
+
+ String element = list[i];
+
+ for (int j = 0; j < count; j++)
+ {
+ if (((element == null) && (list2[j] == null)) || ((element != null) && (element.equals(list2[j]))))
+ {
+ duplicate = true;
+ break;
+ }
+ }
+
+ if (duplicate)
+ continue;
+
+ list2[count++] = list[i];
+ }
+
+ if (count == list2.length)
+ return list2;
+
+ String[] tmp = new String[count];
+ System.arraycopy(list2, 0, tmp, 0, count);
+
+ return tmp;
+ }
+
+ /**
+ * Unless you know what you are doing, you will never need this.
+ *
+ * @param ciphers
+ */
+ public synchronized void setClient2ServerCiphers(String[] ciphers)
+ {
+ if ((ciphers == null) || (ciphers.length == 0))
+ throw new IllegalArgumentException();
+ ciphers = removeDuplicates(ciphers);
+ BlockCipherFactory.checkCipherList(ciphers);
+ cryptoWishList.c2s_enc_algos = ciphers;
+ }
+
+ /**
+ * Unless you know what you are doing, you will never need this.
+ *
+ * @param macs
+ */
+ public synchronized void setClient2ServerMACs(String[] macs)
+ {
+ if ((macs == null) || (macs.length == 0))
+ throw new IllegalArgumentException();
+ macs = removeDuplicates(macs);
+ MAC.checkMacList(macs);
+ cryptoWishList.c2s_mac_algos = macs;
+ }
+
+ /**
+ * Sets the parameters for the diffie-hellman group exchange. Unless you
+ * know what you are doing, you will never need this. Default values are
+ * defined in the {@link DHGexParameters} class.
+ *
+ * @param dgp {@link DHGexParameters}, non null.
+ *
+ */
+ public synchronized void setDHGexParameters(DHGexParameters dgp)
+ {
+ if (dgp == null)
+ throw new IllegalArgumentException();
+
+ dhgexpara = dgp;
+ }
+
+ /**
+ * Unless you know what you are doing, you will never need this.
+ *
+ * @param ciphers
+ */
+ public synchronized void setServer2ClientCiphers(String[] ciphers)
+ {
+ if ((ciphers == null) || (ciphers.length == 0))
+ throw new IllegalArgumentException();
+ ciphers = removeDuplicates(ciphers);
+ BlockCipherFactory.checkCipherList(ciphers);
+ cryptoWishList.s2c_enc_algos = ciphers;
+ }
+
+ /**
+ * Unless you know what you are doing, you will never need this.
+ *
+ * @param macs
+ */
+ public synchronized void setServer2ClientMACs(String[] macs)
+ {
+ if ((macs == null) || (macs.length == 0))
+ throw new IllegalArgumentException();
+
+ macs = removeDuplicates(macs);
+ MAC.checkMacList(macs);
+ cryptoWishList.s2c_mac_algos = macs;
+ }
+
+ /**
+ * Define the set of allowed server host key algorithms to be used for
+ * the following key exchange operations.
+ * <p>
+ * Unless you know what you are doing, you will never need this.
+ *
+ * @param algos An array of allowed server host key algorithms.
+ * SSH-2 defines <code>ssh-dss</code> and <code>ssh-rsa</code>.
+ * The entries of the array must be ordered after preference, i.e.,
+ * the entry at index 0 is the most preferred one. You must specify
+ * at least one entry.
+ */
+ public synchronized void setServerHostKeyAlgorithms(String[] algos)
+ {
+ if ((algos == null) || (algos.length == 0))
+ throw new IllegalArgumentException();
+
+ algos = removeDuplicates(algos);
+ KexManager.checkServerHostkeyAlgorithmsList(algos);
+ cryptoWishList.serverHostKeyAlgorithms = algos;
+ }
+
+ /**
+ * Enable/disable TCP_NODELAY (disable/enable Nagle's algorithm) on the underlying socket.
+ * <p>
+ * Can be called at any time. If the connection has not yet been established
+ * then the passed value will be stored and set after the socket has been set up.
+ * The default value that will be used is <code>false</code>.
+ *
+ * @param enable the argument passed to the <code>Socket.setTCPNoDelay()</code> method.
+ * @throws IOException
+ */
+ public synchronized void setTCPNoDelay(boolean enable) throws IOException
+ {
+ tcpNoDelay = enable;
+
+ if (tm != null)
+ tm.setTcpNoDelay(enable);
+ }
+
+ /**
+ * Used to tell the library that the connection shall be established through a proxy server.
+ * It only makes sense to call this method before calling the {@link #connect() connect()}
+ * method.
+ * <p>
+ * At the moment, only HTTP proxies are supported.
+ * <p>
+ * Note: This method can be called any number of times. The {@link #connect() connect()}
+ * method will use the value set in the last preceding invocation of this method.
+ *
+ * @see HTTPProxyData
+ *
+ * @param proxyData Connection information about the proxy. If <code>null</code>, then
+ * no proxy will be used (non surprisingly, this is also the default).
+ */
+ public synchronized void setProxyData(ProxyData proxyData)
+ {
+ this.proxyData = proxyData;
+ }
+
+ /**
+ * Request a remote port forwarding.
+ * If successful, then forwarded connections will be redirected to the given target address.
+ * You can cancle a requested remote port forwarding by calling
+ * {@link #cancelRemotePortForwarding(int) cancelRemotePortForwarding()}.
+ * <p>
+ * A call of this method will block until the peer either agreed or disagreed to your request-
+ * <p>
+ * Note 1: this method typically fails if you
+ * <ul>
+ * <li>pass a port number for which the used remote user has not enough permissions (i.e., port
+ * < 1024)</li>
+ * <li>or pass a port number that is already in use on the remote server</li>
+ * <li>or if remote port forwarding is disabled on the server.</li>
+ * </ul>
+ * <p>
+ * Note 2: (from the openssh man page): By default, the listening socket on the server will be
+ * bound to the loopback interface only. This may be overriden by specifying a bind address.
+ * Specifying a remote bind address will only succeed if the server's <b>GatewayPorts</b> option
+ * is enabled (see sshd_config(5)).
+ *
+ * @param bindAddress address to bind to on the server:
+ * <ul>
+ * <li>"" means that connections are to be accepted on all protocol families
+ * supported by the SSH implementation</li>
+ * <li>"0.0.0.0" means to listen on all IPv4 addresses</li>
+ * <li>"::" means to listen on all IPv6 addresses</li>
+ * <li>"localhost" means to listen on all protocol families supported by the SSH
+ * implementation on loopback addresses only, [RFC3330] and RFC3513]</li>
+ * <li>"127.0.0.1" and "::1" indicate listening on the loopback interfaces for
+ * IPv4 and IPv6 respectively</li>
+ * </ul>
+ * @param bindPort port number to bind on the server (must be > 0)
+ * @param targetAddress the target address (IP or hostname)
+ * @param targetPort the target port
+ * @throws IOException
+ */
+ public synchronized void requestRemotePortForwarding(String bindAddress, int bindPort, String targetAddress,
+ int targetPort) throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("You need to establish a connection first.");
+
+ if (!authenticated)
+ throw new IllegalStateException("The connection is not authenticated.");
+
+ if ((bindAddress == null) || (targetAddress == null) || (bindPort <= 0) || (targetPort <= 0))
+ throw new IllegalArgumentException();
+
+ cm.requestGlobalForward(bindAddress, bindPort, targetAddress, targetPort);
+ }
+
+ /**
+ * Cancel an earlier requested remote port forwarding.
+ * Currently active forwardings will not be affected (e.g., disrupted).
+ * Note that further connection forwarding requests may be received until
+ * this method has returned.
+ *
+ * @param bindPort the allocated port number on the server
+ * @throws IOException if the remote side refuses the cancel request or another low
+ * level error occurs (e.g., the underlying connection is closed)
+ */
+ public synchronized void cancelRemotePortForwarding(int bindPort) throws IOException
+ {
+ if (tm == null)
+ throw new IllegalStateException("You need to establish a connection first.");
+
+ if (!authenticated)
+ throw new IllegalStateException("The connection is not authenticated.");
+
+ cm.requestCancelGlobalForward(bindPort);
+ }
+
+ /**
+ * Provide your own instance of SecureRandom. Can be used, e.g., if you
+ * want to seed the used SecureRandom generator manually.
+ * <p>
+ * The SecureRandom instance is used during key exchanges, public key authentication,
+ * x11 cookie generation and the like.
+ *
+ * @param rnd a SecureRandom instance
+ */
+ public synchronized void setSecureRandom(SecureRandom rnd)
+ {
+ if (rnd == null)
+ throw new IllegalArgumentException();
+
+ this.generator = rnd;
+ }
+}
Code Review / controller.git / blobdiff