src/java.security.sasl/share/classes/javax/security/sasl/SaslServer.java
changeset 47216 71c04702a3d5
parent 25859 3317bb8137f4
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.security.sasl/share/classes/javax/security/sasl/SaslServer.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,220 @@
+/*
+ * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package javax.security.sasl;
+
+/**
+ * Performs SASL authentication as a server.
+ *<p>
+ * A server such an LDAP server gets an instance of this
+ * class in order to perform authentication defined by a specific SASL
+ * mechanism. Invoking methods on the {@code SaslServer} instance
+ * generates challenges according to the SASL
+ * mechanism implemented by the {@code SaslServer}.
+ * As the authentication proceeds, the instance
+ * encapsulates the state of a SASL server's authentication exchange.
+ *<p>
+ * Here's an example of how an LDAP server might use a {@code SaslServer}.
+ * It first gets an instance of a {@code SaslServer} for the SASL mechanism
+ * requested by the client:
+ *<blockquote><pre>
+ * SaslServer ss = Sasl.createSaslServer(mechanism,
+ *     "ldap", myFQDN, props, callbackHandler);
+ *</pre></blockquote>
+ * It can then proceed to use the server for authentication.
+ * For example, suppose the LDAP server received an LDAP BIND request
+ * containing the name of the SASL mechanism and an (optional) initial
+ * response. It then might use the server as follows:
+ *<blockquote><pre>{@code
+ * while (!ss.isComplete()) {
+ *     try {
+ *         byte[] challenge = ss.evaluateResponse(response);
+ *         if (ss.isComplete()) {
+ *             status = ldap.sendBindResponse(mechanism, challenge, SUCCESS);
+ *         } else {
+ *             status = ldap.sendBindResponse(mechanism, challenge,
+                   SASL_BIND_IN_PROGRESS);
+ *             response = ldap.readBindRequest();
+ *         }
+ *     } catch (SaslException e) {
+ *          status = ldap.sendErrorResponse(e);
+ *          break;
+ *     }
+ * }
+ * if (ss.isComplete() && status == SUCCESS) {
+ *    String qop = (String) sc.getNegotiatedProperty(Sasl.QOP);
+ *    if (qop != null
+ *        && (qop.equalsIgnoreCase("auth-int")
+ *            || qop.equalsIgnoreCase("auth-conf"))) {
+ *
+ *      // Use SaslServer.wrap() and SaslServer.unwrap() for future
+ *      // communication with client
+ *      ldap.in = new SecureInputStream(ss, ldap.in);
+ *      ldap.out = new SecureOutputStream(ss, ldap.out);
+ *    }
+ * }
+ *}</pre></blockquote>
+ *
+ * @since 1.5
+ *
+ * @see Sasl
+ * @see SaslServerFactory
+ *
+ * @author Rosanna Lee
+ * @author Rob Weltman
+ */
+public abstract interface SaslServer {
+
+    /**
+     * Returns the IANA-registered mechanism name of this SASL server.
+     * (e.g. "CRAM-MD5", "GSSAPI").
+     * @return A non-null string representing the IANA-registered mechanism name.
+     */
+    public abstract String getMechanismName();
+
+    /**
+     * Evaluates the response data and generates a challenge.
+     *
+     * If a response is received from the client during the authentication
+     * process, this method is called to prepare an appropriate next
+     * challenge to submit to the client. The challenge is null if the
+     * authentication has succeeded and no more challenge data is to be sent
+     * to the client. It is non-null if the authentication must be continued
+     * by sending a challenge to the client, or if the authentication has
+     * succeeded but challenge data needs to be processed by the client.
+     * {@code isComplete()} should be called
+     * after each call to {@code evaluateResponse()},to determine if any further
+     * response is needed from the client.
+     *
+     * @param response The non-null (but possibly empty) response sent
+     * by the client.
+     *
+     * @return The possibly null challenge to send to the client.
+     * It is null if the authentication has succeeded and there is
+     * no more challenge data to be sent to the client.
+     * @exception SaslException If an error occurred while processing
+     * the response or generating a challenge.
+     */
+    public abstract byte[] evaluateResponse(byte[] response)
+        throws SaslException;
+
+    /**
+      * Determines whether the authentication exchange has completed.
+      * This method is typically called after each invocation of
+      * {@code evaluateResponse()} to determine whether the
+      * authentication has completed successfully or should be continued.
+      * @return true if the authentication exchange has completed; false otherwise.
+      */
+    public abstract boolean isComplete();
+
+    /**
+     * Reports the authorization ID in effect for the client of this
+     * session.
+     * This method can only be called if isComplete() returns true.
+     * @return The authorization ID of the client.
+     * @exception IllegalStateException if this authentication session has not completed
+     */
+    public String getAuthorizationID();
+
+    /**
+     * Unwraps a byte array received from the client.
+     * This method can be called only after the authentication exchange has
+     * completed (i.e., when {@code isComplete()} returns true) and only if
+     * the authentication exchange has negotiated integrity and/or privacy
+     * as the quality of protection; otherwise,
+     * an {@code IllegalStateException} is thrown.
+     *<p>
+     * {@code incoming} is the contents of the SASL buffer as defined in RFC 2222
+     * without the leading four octet field that represents the length.
+     * {@code offset} and {@code len} specify the portion of {@code incoming}
+     * to use.
+     *
+     * @param incoming A non-null byte array containing the encoded bytes
+     *                from the client.
+     * @param offset The starting position at {@code incoming} of the bytes to use.
+     * @param len The number of bytes from {@code incoming} to use.
+     * @return A non-null byte array containing the decoded bytes.
+     * @exception SaslException if {@code incoming} cannot be successfully
+     * unwrapped.
+     * @exception IllegalStateException if the authentication exchange has
+     * not completed, or if the negotiated quality of protection
+     * has neither integrity nor privacy
+     */
+    public abstract byte[] unwrap(byte[] incoming, int offset, int len)
+        throws SaslException;
+
+    /**
+     * Wraps a byte array to be sent to the client.
+     * This method can be called only after the authentication exchange has
+     * completed (i.e., when {@code isComplete()} returns true) and only if
+     * the authentication exchange has negotiated integrity and/or privacy
+     * as the quality of protection; otherwise, a {@code SaslException} is thrown.
+     *<p>
+     * The result of this method
+     * will make up the contents of the SASL buffer as defined in RFC 2222
+     * without the leading four octet field that represents the length.
+     * {@code offset} and {@code len} specify the portion of {@code outgoing}
+     * to use.
+     *
+     * @param outgoing A non-null byte array containing the bytes to encode.
+     * @param offset The starting position at {@code outgoing} of the bytes to use.
+     * @param len The number of bytes from {@code outgoing} to use.
+     * @return A non-null byte array containing the encoded bytes.
+     * @exception SaslException if {@code outgoing} cannot be successfully
+     * wrapped.
+     * @exception IllegalStateException if the authentication exchange has
+     * not completed, or if the negotiated quality of protection has
+     * neither integrity nor privacy.
+     */
+    public abstract byte[] wrap(byte[] outgoing, int offset, int len)
+        throws SaslException;
+
+    /**
+     * Retrieves the negotiated property.
+     * This method can be called only after the authentication exchange has
+     * completed (i.e., when {@code isComplete()} returns true); otherwise, an
+     * {@code IllegalStateException} is thrown.
+     * <p>
+     * The {@link Sasl} class includes several well-known property names
+     * (For example, {@link Sasl#QOP}). A SASL provider can support other
+     * properties which are specific to the vendor and/or a mechanism.
+     *
+     * @param propName the property
+     * @return The value of the negotiated property. If null, the property was
+     * not negotiated or is not applicable to this mechanism.
+     * @exception IllegalStateException if this authentication exchange has not completed
+     */
+
+    public abstract Object getNegotiatedProperty(String propName);
+
+     /**
+      * Disposes of any system resources or security-sensitive information
+      * the SaslServer might be using. Invoking this method invalidates
+      * the SaslServer instance. This method is idempotent.
+      * @throws SaslException If a problem was encountered while disposing
+      * the resources.
+      */
+    public abstract void dispose() throws SaslException;
+}