--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/src/main/java/ch/ethz/ssh2/ServerAuthenticationCallback.java	Thu Dec 03 11:23:55 2015 -0800
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2012-2013 Christian Plattner. All rights reserved.
+ * Please refer to the LICENSE.txt for licensing details.
+ */
+
+package ch.ethz.ssh2;
+
+/**
+ * A callback used during the authentication phase (see RFC 4252) when
+ * implementing a SSH server.
+ *
+ * @author Christian Plattner
+ * @version 2.50, 03/15/10
+ */
+public interface ServerAuthenticationCallback {
+    /**
+     * The method name for host-based authentication.
+     */
+    public final String METHOD_HOSTBASED = "hostbased";
+
+    /**
+     * The method name for public-key authentication.
+     */
+    public final String METHOD_PUBLICKEY = "publickey";
+
+    /**
+     * The method name for password authentication.
+     */
+    public final String METHOD_PASSWORD = "password";
+
+    /**
+     * Called when the client enters authentication.
+     * This gives you the chance to set a custom authentication banner
+     * for this SSH-2 session. This is the first method called in this interface.
+     * It will only called at most once per <code>ServerConnection</code>.
+     *
+     * @param sc The corresponding <code>ServerConnection</code>
+     * @return The authentication banner or <code>NULL</code> in case no banner should be send.
+     */
+    public String initAuthentication(ServerConnection sc);
+
+    /**
+     * Return the authentication methods that are currently available to the client.
+     * Be prepared to return this information at any time during the authentication procedure.
+     * <p/>
+     * The returned name-list of 'method names' (see RFC4252) indicate the authentication methods
+     * that may productively continue the authentication dialog.
+     * </p>
+     * It is RECOMMENDED that servers only include those 'method name'
+     * values in the name-list that are actually useful.  However, it is not
+     * illegal to include 'method name' values that cannot be used to
+     * authenticate the user.
+     * <p/>
+     * Already successfully completed authentications SHOULD NOT be included
+     * in the name-list, unless they should be performed again for some reason.
+     *
+     * @see #METHOD_HOSTBASED
+     * @see #METHOD_PASSWORD
+     * @see #METHOD_PUBLICKEY
+     *
+     * @param sc
+     * @return A list of method names.
+     */
+    public String[] getRemainingAuthMethods(ServerConnection sc);
+
+    /**
+     * Typically, this will be called be the client to get the list of
+     * authentication methods that can continue. You should simply return
+     * {@link AuthenticationResult#FAILURE}.
+     *
+     * @param sc
+     * @param username Name of the user that wants to log in with the "none" method.
+     * @return
+     */
+    public AuthenticationResult authenticateWithNone(ServerConnection sc, String username);
+
+    public AuthenticationResult authenticateWithPassword(ServerConnection sc, String username, String password);
+
+    /**
+     * NOTE: Not implemented yet.
+     *
+     * @param sc
+     * @param username
+     * @param algorithm
+     * @param publickey
+     * @param signature
+     * @return
+     */
+    public AuthenticationResult authenticateWithPublicKey(ServerConnection sc, String username, String algorithm,
+            byte[] publickey, byte[] signature);
+}