J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2000-2004 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package javax.security.sasl; |
| 27 | |
| 28 | /** |
| 29 | * Performs SASL authentication as a server. |
| 30 | *<p> |
| 31 | * A server such an LDAP server gets an instance of this |
| 32 | * class in order to perform authentication defined by a specific SASL |
| 33 | * mechanism. Invoking methods on the <tt>SaslServer</tt> instance |
| 34 | * generates challenges according to the SASL |
| 35 | * mechanism implemented by the <tt>SaslServer</tt>. |
| 36 | * As the authentication proceeds, the instance |
| 37 | * encapsulates the state of a SASL server's authentication exchange. |
| 38 | *<p> |
| 39 | * Here's an example of how an LDAP server might use a <tt>SaslServer</tt>. |
| 40 | * It first gets an instance of a <tt>SaslServer</tt> for the SASL mechanism |
| 41 | * requested by the client: |
| 42 | *<blockquote><pre> |
| 43 | * SaslServer ss = Sasl.createSaslServer(mechanism, |
| 44 | * "ldap", myFQDN, props, callbackHandler); |
| 45 | *</pre></blockquote> |
| 46 | * It can then proceed to use the server for authentication. |
| 47 | * For example, suppose the LDAP server received an LDAP BIND request |
| 48 | * containing the name of the SASL mechanism and an (optional) initial |
| 49 | * response. It then might use the server as follows: |
| 50 | *<blockquote><pre> |
| 51 | * while (!ss.isComplete()) { |
| 52 | * try { |
| 53 | * byte[] challenge = ss.evaluateResponse(response); |
| 54 | * if (ss.isComplete()) { |
| 55 | * status = ldap.sendBindResponse(mechanism, challenge, SUCCESS); |
| 56 | * } else { |
| 57 | * status = ldap.sendBindResponse(mechanism, challenge, |
| 58 | SASL_BIND_IN_PROGRESS); |
| 59 | * response = ldap.readBindRequest(); |
| 60 | * } |
| 61 | * } catch (SaslException e) { |
| 62 | * status = ldap.sendErrorResponse(e); |
| 63 | * break; |
| 64 | * } |
| 65 | * } |
| 66 | * if (ss.isComplete() && status == SUCCESS) { |
| 67 | * String qop = (String) sc.getNegotiatedProperty(Sasl.QOP); |
| 68 | * if (qop != null |
| 69 | * && (qop.equalsIgnoreCase("auth-int") |
| 70 | * || qop.equalsIgnoreCase("auth-conf"))) { |
| 71 | * |
| 72 | * // Use SaslServer.wrap() and SaslServer.unwrap() for future |
| 73 | * // communication with client |
| 74 | * ldap.in = new SecureInputStream(ss, ldap.in); |
| 75 | * ldap.out = new SecureOutputStream(ss, ldap.out); |
| 76 | * } |
| 77 | * } |
| 78 | *</pre></blockquote> |
| 79 | * |
| 80 | * @since 1.5 |
| 81 | * |
| 82 | * @see Sasl |
| 83 | * @see SaslServerFactory |
| 84 | * |
| 85 | * @author Rosanna Lee |
| 86 | * @author Rob Weltman |
| 87 | */ |
| 88 | public abstract interface SaslServer { |
| 89 | |
| 90 | /** |
| 91 | * Returns the IANA-registered mechanism name of this SASL server. |
| 92 | * (e.g. "CRAM-MD5", "GSSAPI"). |
| 93 | * @return A non-null string representing the IANA-registered mechanism name. |
| 94 | */ |
| 95 | public abstract String getMechanismName(); |
| 96 | |
| 97 | /** |
| 98 | * Evaluates the response data and generates a challenge. |
| 99 | * |
| 100 | * If a response is received from the client during the authentication |
| 101 | * process, this method is called to prepare an appropriate next |
| 102 | * challenge to submit to the client. The challenge is null if the |
| 103 | * authentication has succeeded and no more challenge data is to be sent |
| 104 | * to the client. It is non-null if the authentication must be continued |
| 105 | * by sending a challenge to the client, or if the authentication has |
| 106 | * succeeded but challenge data needs to be processed by the client. |
| 107 | * <tt>isComplete()</tt> should be called |
| 108 | * after each call to <tt>evaluateResponse()</tt>,to determine if any further |
| 109 | * response is needed from the client. |
| 110 | * |
| 111 | * @param response The non-null (but possibly empty) response sent |
| 112 | * by the client. |
| 113 | * |
| 114 | * @return The possibly null challenge to send to the client. |
| 115 | * It is null if the authentication has succeeded and there is |
| 116 | * no more challenge data to be sent to the client. |
| 117 | * @exception SaslException If an error occurred while processing |
| 118 | * the response or generating a challenge. |
| 119 | */ |
| 120 | public abstract byte[] evaluateResponse(byte[] response) |
| 121 | throws SaslException; |
| 122 | |
| 123 | /** |
| 124 | * Determines whether the authentication exchange has completed. |
| 125 | * This method is typically called after each invocation of |
| 126 | * <tt>evaluateResponse()</tt> to determine whether the |
| 127 | * authentication has completed successfully or should be continued. |
| 128 | * @return true if the authentication exchange has completed; false otherwise. |
| 129 | */ |
| 130 | public abstract boolean isComplete(); |
| 131 | |
| 132 | /** |
| 133 | * Reports the authorization ID in effect for the client of this |
| 134 | * session. |
| 135 | * This method can only be called if isComplete() returns true. |
| 136 | * @return The authorization ID of the client. |
| 137 | * @exception IllegalStateException if this authentication session has not completed |
| 138 | */ |
| 139 | public String getAuthorizationID(); |
| 140 | |
| 141 | /** |
| 142 | * Unwraps a byte array received from the client. |
| 143 | * This method can be called only after the authentication exchange has |
| 144 | * completed (i.e., when <tt>isComplete()</tt> returns true) and only if |
| 145 | * the authentication exchange has negotiated integrity and/or privacy |
| 146 | * as the quality of protection; otherwise, |
| 147 | * an <tt>IllegalStateException</tt> is thrown. |
| 148 | *<p> |
| 149 | * <tt>incoming</tt> is the contents of the SASL buffer as defined in RFC 2222 |
| 150 | * without the leading four octet field that represents the length. |
| 151 | * <tt>offset</tt> and <tt>len</tt> specify the portion of <tt>incoming</tt> |
| 152 | * to use. |
| 153 | * |
| 154 | * @param incoming A non-null byte array containing the encoded bytes |
| 155 | * from the client. |
| 156 | * @param offset The starting position at <tt>incoming</tt> of the bytes to use. |
| 157 | * @param len The number of bytes from <tt>incoming</tt> to use. |
| 158 | * @return A non-null byte array containing the decoded bytes. |
| 159 | * @exception SaslException if <tt>incoming</tt> cannot be successfully |
| 160 | * unwrapped. |
| 161 | * @exception IllegalStateException if the authentication exchange has |
| 162 | * not completed, or if the negotiated quality of protection |
| 163 | * has neither integrity nor privacy |
| 164 | */ |
| 165 | public abstract byte[] unwrap(byte[] incoming, int offset, int len) |
| 166 | throws SaslException; |
| 167 | |
| 168 | /** |
| 169 | * Wraps a byte array to be sent to the client. |
| 170 | * This method can be called only after the authentication exchange has |
| 171 | * completed (i.e., when <tt>isComplete()</tt> returns true) and only if |
| 172 | * the authentication exchange has negotiated integrity and/or privacy |
| 173 | * as the quality of protection; otherwise, a <tt>SaslException</tt> is thrown. |
| 174 | *<p> |
| 175 | * The result of this method |
| 176 | * will make up the contents of the SASL buffer as defined in RFC 2222 |
| 177 | * without the leading four octet field that represents the length. |
| 178 | * <tt>offset</tt> and <tt>len</tt> specify the portion of <tt>outgoing</tt> |
| 179 | * to use. |
| 180 | * |
| 181 | * @param outgoing A non-null byte array containing the bytes to encode. |
| 182 | * @param offset The starting position at <tt>outgoing</tt> of the bytes to use. |
| 183 | * @param len The number of bytes from <tt>outgoing</tt> to use. |
| 184 | * @return A non-null byte array containing the encoded bytes. |
| 185 | * @exception SaslException if <tt>outgoing</tt> cannot be successfully |
| 186 | * wrapped. |
| 187 | * @exception IllegalStateException if the authentication exchange has |
| 188 | * not completed, or if the negotiated quality of protection has |
| 189 | * neither integrity nor privacy. |
| 190 | */ |
| 191 | public abstract byte[] wrap(byte[] outgoing, int offset, int len) |
| 192 | throws SaslException; |
| 193 | |
| 194 | /** |
| 195 | * Retrieves the negotiated property. |
| 196 | * This method can be called only after the authentication exchange has |
| 197 | * completed (i.e., when <tt>isComplete()</tt> returns true); otherwise, an |
| 198 | * <tt>IllegalStateException</tt> is thrown. |
| 199 | * |
| 200 | * @param propName the property |
| 201 | * @return The value of the negotiated property. If null, the property was |
| 202 | * not negotiated or is not applicable to this mechanism. |
| 203 | * @exception IllegalStateException if this authentication exchange has not completed |
| 204 | */ |
| 205 | |
| 206 | public abstract Object getNegotiatedProperty(String propName); |
| 207 | |
| 208 | /** |
| 209 | * Disposes of any system resources or security-sensitive information |
| 210 | * the SaslServer might be using. Invoking this method invalidates |
| 211 | * the SaslServer instance. This method is idempotent. |
| 212 | * @throws SaslException If a problem was encountered while disposing |
| 213 | * the resources. |
| 214 | */ |
| 215 | public abstract void dispose() throws SaslException; |
| 216 | } |