diff options
Diffstat (limited to 'lib/src/main/java/com/trilead/ssh2/Connection.java')
| -rw-r--r-- | lib/src/main/java/com/trilead/ssh2/Connection.java | 3256 |
1 files changed, 1628 insertions, 1628 deletions
diff --git a/lib/src/main/java/com/trilead/ssh2/Connection.java b/lib/src/main/java/com/trilead/ssh2/Connection.java index c1e8711..163fdb5 100644 --- a/lib/src/main/java/com/trilead/ssh2/Connection.java +++ b/lib/src/main/java/com/trilead/ssh2/Connection.java @@ -1,1628 +1,1628 @@ -
-package com.trilead.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.KeyPair;
-import java.security.SecureRandom;
-import java.security.Security;
-import java.util.Set;
-import java.util.Vector;
-
-import com.trilead.ssh2.auth.AuthenticationManager;
-import com.trilead.ssh2.channel.ChannelManager;
-import com.trilead.ssh2.crypto.CryptoWishList;
-import com.trilead.ssh2.crypto.cipher.BlockCipherFactory;
-import com.trilead.ssh2.crypto.digest.MAC;
-import com.trilead.ssh2.log.Logger;
-import com.trilead.ssh2.packets.PacketIgnore;
-import com.trilead.ssh2.transport.KexManager;
-import com.trilead.ssh2.transport.TransportManager;
-import com.trilead.ssh2.util.TimeoutService;
-import com.trilead.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, plattner@trilead.com
- * @version $Id: Connection.java,v 1.3 2008/04/01 12:38:09 cplattne Exp $
- */
-
-public class Connection
-{
- /**
- * The identifier presented to the SSH-2 server.
- */
- public final static String identification = "TrileadSSH2Java_213";
-
- /**
- * 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 boolean compression = 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 Vector<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;
- }
-
- /**
- * 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;
- }
-
- /**
- * 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>
- * 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 key
- * A <code>RSAPrivateKey</code> or <code>DSAPrivateKey</code>
- * containing a DSA or RSA private key of
- * the user in Trilead object format.
- *
- * @return whether the connection is now authenticated.
- * @throws IOException
- */
- public synchronized boolean authenticateWithPublicKey(String user, KeyPair pair)
- 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 (pair == null)
- throw new IllegalArgumentException("Key pair argument is null");
-
- authenticated = am.authenticatePublicKey(user, pair, 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.
- *
- * @see ConnectionMonitor
- *
- * @param cmon
- * An object implementing the <code>ConnectionMonitor</code>
- * interface.
- */
- public synchronized void addConnectionMonitor(ConnectionMonitor cmon)
- {
- if (cmon == null)
- throw new IllegalArgumentException("cmon argument is null");
-
- connectionMonitors.addElement(cmon);
-
- if (tm != null)
- tm.setConnectionMonitors(connectionMonitors);
- }
-
- /**
- * Controls whether compression is used on the link or not.
- * <p>
- * Note: This can only be called before connect()
- * @param enabled whether to enable compression
- * @throws IOException
- */
- public synchronized void setCompression(boolean enabled) throws IOException {
- if (tm != null)
- throw new IOException("Connection to " + hostname + " is already in connected state!");
-
- compression = enabled;
- }
-
- /**
- * 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);
- }
-
- private 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(hostname, port);
-
- tm.setConnectionMonitors(connectionMonitors);
-
- // Don't offer compression if not requested
- if (!compression) {
- cryptoWishList.c2s_comp_algos = new String[] { "none" };
- cryptoWishList.s2c_comp_algos = new String[] { "none" };
- }
-
- /*
- * 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.initialize(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);
- }
-
- /**
- * Creates a new {@link DynamicPortForwarder}. A
- * <code>DynamicPortForwarder</code> forwards TCP/IP connections that arrive
- * at a local port via the secure tunnel to another host that is chosen via
- * the SOCKS protocol.
- * <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
- * @return A {@link DynamicPortForwarder} object.
- * @throws IOException
- */
- public synchronized DynamicPortForwarder createDynamicPortForwarder(int local_port) 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 DynamicPortForwarder(cm, local_port);
- }
-
- /**
- * Creates a new {@link DynamicPortForwarder}. A
- * <code>DynamicPortForwarder</code> forwards TCP/IP connections that arrive
- * at a local port via the secure tunnel to another host that is chosen via
- * the SOCKS protocol.
- * <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.
- * @return A {@link DynamicPortForwarder} object.
- * @throws IOException
- */
- public synchronized DynamicPortForwarder createDynamicPortForwarder(InetSocketAddress addr) 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 DynamicPortForwarder(cm, addr);
- }
-
- /**
- * 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);
- }
-
- /**
- * 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 final 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;
- }
-
- /**
- * Enable/disable debug logging. <b>Only do this when requested by Trilead
- * support.</b>
- * <p>
- * For speed reasons, some static variables used to check whether debugging
- * is enabled are not protected with locks. In other words, if you
- * dynamicaly enable/disable debug logging, then some threads may still use
- * the old setting. To be on the safe side, enable debugging before doing
- * the <code>connect()</code> call.
- *
- * @param enable
- * on/off
- * @param logger
- * a {@link DebugLogger DebugLogger} instance, <code>null</code>
- * means logging using the simple logger which logs all messages
- * to to stderr. Ignored if enabled is <code>false</code>
- */
- public synchronized void enableDebugging(boolean enable, DebugLogger logger)
- {
- Logger.enabled = enable;
-
- if (enable == false)
- {
- Logger.logger = null;
- }
- else
- {
- if (logger == null)
- {
- logger = new DebugLogger()
- {
-
- public void log(int level, String className, String message)
- {
- long now = System.currentTimeMillis();
- System.err.println(now + " : " + className + ": " + message);
- }
- };
- }
-
- Logger.logger = logger;
- }
- }
-
- /**
- * This method can be used to perform end-to-end connection testing. It
- * sends a 'ping' message to the server and waits for the 'pong' from the
- * server.
- * <p>
- * When this method throws an exception, then you can assume that the
- * connection should be abandoned.
- * <p>
- * Note: Works only after one has passed successfully the authentication
- * step.
- * <p>
- * Implementation details: this method sends a SSH_MSG_GLOBAL_REQUEST
- * request ('trilead-ping') to the server and waits for the
- * SSH_MSG_REQUEST_FAILURE reply packet from the server.
- *
- * @throws IOException
- * in case of any problem
- */
- public synchronized void ping() 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.requestGlobalTrileadPing();
- }
-}
+ +package com.trilead.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.KeyPair; +import java.security.SecureRandom; +import java.security.Security; +import java.util.Set; +import java.util.Vector; + +import com.trilead.ssh2.auth.AuthenticationManager; +import com.trilead.ssh2.channel.ChannelManager; +import com.trilead.ssh2.crypto.CryptoWishList; +import com.trilead.ssh2.crypto.cipher.BlockCipherFactory; +import com.trilead.ssh2.crypto.digest.MAC; +import com.trilead.ssh2.log.Logger; +import com.trilead.ssh2.packets.PacketIgnore; +import com.trilead.ssh2.transport.KexManager; +import com.trilead.ssh2.transport.TransportManager; +import com.trilead.ssh2.util.TimeoutService; +import com.trilead.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, plattner@trilead.com + * @version $Id: Connection.java,v 1.3 2008/04/01 12:38:09 cplattne Exp $ + */ + +public class Connection +{ + /** + * The identifier presented to the SSH-2 server. + */ + public final static String identification = "TrileadSSH2Java_213"; + + /** + * 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 boolean compression = 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 Vector<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; + } + + /** + * 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; + } + + /** + * 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> + * 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 key + * A <code>RSAPrivateKey</code> or <code>DSAPrivateKey</code> + * containing a DSA or RSA private key of + * the user in Trilead object format. + * + * @return whether the connection is now authenticated. + * @throws IOException + */ + public synchronized boolean authenticateWithPublicKey(String user, KeyPair pair) + 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 (pair == null) + throw new IllegalArgumentException("Key pair argument is null"); + + authenticated = am.authenticatePublicKey(user, pair, 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. + * + * @see ConnectionMonitor + * + * @param cmon + * An object implementing the <code>ConnectionMonitor</code> + * interface. + */ + public synchronized void addConnectionMonitor(ConnectionMonitor cmon) + { + if (cmon == null) + throw new IllegalArgumentException("cmon argument is null"); + + connectionMonitors.addElement(cmon); + + if (tm != null) + tm.setConnectionMonitors(connectionMonitors); + } + + /** + * Controls whether compression is used on the link or not. + * <p> + * Note: This can only be called before connect() + * @param enabled whether to enable compression + * @throws IOException + */ + public synchronized void setCompression(boolean enabled) throws IOException { + if (tm != null) + throw new IOException("Connection to " + hostname + " is already in connected state!"); + + compression = enabled; + } + + /** + * 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); + } + + private 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(hostname, port); + + tm.setConnectionMonitors(connectionMonitors); + + // Don't offer compression if not requested + if (!compression) { + cryptoWishList.c2s_comp_algos = new String[] { "none" }; + cryptoWishList.s2c_comp_algos = new String[] { "none" }; + } + + /* + * 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.initialize(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); + } + + /** + * Creates a new {@link DynamicPortForwarder}. A + * <code>DynamicPortForwarder</code> forwards TCP/IP connections that arrive + * at a local port via the secure tunnel to another host that is chosen via + * the SOCKS protocol. + * <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 + * @return A {@link DynamicPortForwarder} object. + * @throws IOException + */ + public synchronized DynamicPortForwarder createDynamicPortForwarder(int local_port) 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 DynamicPortForwarder(cm, local_port); + } + + /** + * Creates a new {@link DynamicPortForwarder}. A + * <code>DynamicPortForwarder</code> forwards TCP/IP connections that arrive + * at a local port via the secure tunnel to another host that is chosen via + * the SOCKS protocol. + * <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. + * @return A {@link DynamicPortForwarder} object. + * @throws IOException + */ + public synchronized DynamicPortForwarder createDynamicPortForwarder(InetSocketAddress addr) 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 DynamicPortForwarder(cm, addr); + } + + /** + * 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); + } + + /** + * 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 final 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; + } + + /** + * Enable/disable debug logging. <b>Only do this when requested by Trilead + * support.</b> + * <p> + * For speed reasons, some static variables used to check whether debugging + * is enabled are not protected with locks. In other words, if you + * dynamicaly enable/disable debug logging, then some threads may still use + * the old setting. To be on the safe side, enable debugging before doing + * the <code>connect()</code> call. + * + * @param enable + * on/off + * @param logger + * a {@link DebugLogger DebugLogger} instance, <code>null</code> + * means logging using the simple logger which logs all messages + * to to stderr. Ignored if enabled is <code>false</code> + */ + public synchronized void enableDebugging(boolean enable, DebugLogger logger) + { + Logger.enabled = enable; + + if (enable == false) + { + Logger.logger = null; + } + else + { + if (logger == null) + { + logger = new DebugLogger() + { + + public void log(int level, String className, String message) + { + long now = System.currentTimeMillis(); + System.err.println(now + " : " + className + ": " + message); + } + }; + } + + Logger.logger = logger; + } + } + + /** + * This method can be used to perform end-to-end connection testing. It + * sends a 'ping' message to the server and waits for the 'pong' from the + * server. + * <p> + * When this method throws an exception, then you can assume that the + * connection should be abandoned. + * <p> + * Note: Works only after one has passed successfully the authentication + * step. + * <p> + * Implementation details: this method sends a SSH_MSG_GLOBAL_REQUEST + * request ('trilead-ping') to the server and waits for the + * SSH_MSG_REQUEST_FAILURE reply packet from the server. + * + * @throws IOException + * in case of any problem + */ + public synchronized void ping() 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.requestGlobalTrileadPing(); + } +} |