/* * Copyright (c) 2000, 2004, Oracle and/or its affiliates. All rights reserved. * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. * * * * * * * * * * * * * * * * * * * * */ package javax.security.sasl; /** * Performs SASL authentication as a server. *

* 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 SaslServer instance * generates challenges according to the SASL * mechanism implemented by the SaslServer. * As the authentication proceeds, the instance * encapsulates the state of a SASL server's authentication exchange. *

* Here's an example of how an LDAP server might use a SaslServer. * It first gets an instance of a SaslServer for the SASL mechanism * requested by the client: *

 * SaslServer ss = Sasl.createSaslServer(mechanism,
 *     "ldap", myFQDN, props, callbackHandler);
 *
* 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: *
 * 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);
 *    }
 * }
 *
* * @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. * isComplete() should be called * after each call to 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 * 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 isComplete() returns true) and only if * the authentication exchange has negotiated integrity and/or privacy * as the quality of protection; otherwise, * an IllegalStateException is thrown. *

* incoming is the contents of the SASL buffer as defined in RFC 2222 * without the leading four octet field that represents the length. * offset and len specify the portion of incoming * to use. * * @param incoming A non-null byte array containing the encoded bytes * from the client. * @param offset The starting position at incoming of the bytes to use. * @param len The number of bytes from incoming to use. * @return A non-null byte array containing the decoded bytes. * @exception SaslException if 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 isComplete() returns true) and only if * the authentication exchange has negotiated integrity and/or privacy * as the quality of protection; otherwise, a SaslException is thrown. *

* 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. * offset and len specify the portion of outgoing * to use. * * @param outgoing A non-null byte array containing the bytes to encode. * @param offset The starting position at outgoing of the bytes to use. * @param len The number of bytes from outgoing to use. * @return A non-null byte array containing the encoded bytes. * @exception SaslException if 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 isComplete() returns true); otherwise, an * IllegalStateException is thrown. * * @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; }