Pam xref
1 /***
2 * Copyright 2003-2007 Greg Luck
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package net.sf.jpam;
18
19 import org.apache.commons.logging.Log;
20 import org.apache.commons.logging.LogFactory;
21
22 /***
23 * The PAM bridging class. Most of the work is done here.
24 * <p/>
25 * To see debugging output for this class and native code, set the installed logging toolkit level
26 * for this class to DEBUG or equivalent. The debugging output for the native code will
27 * be sent to <code>STDOUT</code>.
28 * <p/>
29 * This class may be called directly, or by using JAAS, via the {@link net.sf.jpam.jaas.JpamLoginModule}.
30 *
31 * @author <a href="mailto:gregluck@users.sourceforge.net">Greg Luck</a>
32 * @author David Lutterkort, RedHat
33 * @author Ken Huffman
34 * @version $Id: Pam.java 20 2007年04月15日 00:46:53Z gregluck $
35 *
36 */
37 public class Pam {
38 private static final Log LOG = LogFactory.getLog(Pam.class.getName());
39 private static final String JPAM_SHARED_LIBRARY_NAME = "jpam";
40 private String serviceName;
41
42
43 /***
44 * The default service name of "net-sf-pam".
45 * <p/>
46 * This service is expected to be configured in /etc/pam.d
47 */
48 public static final String DEFAULT_SERVICE_NAME = "net-sf-" + JPAM_SHARED_LIBRARY_NAME;
49
50 static {
51 System.loadLibrary(JPAM_SHARED_LIBRARY_NAME);
52 }
53
54
55 /***
56 * Creates a new Pam object configured to use the {@link #DEFAULT_SERVICE_NAME}
57 */
58 public Pam() {
59 this(DEFAULT_SERVICE_NAME);
60 }
61
62 /***
63 * Creates a new PAM object configured with the specified service name.
64 * <p/>
65 * A file with the same name must exist in /etc/pam.d
66 *
67 * @param serviceName
68 * @throws NullPointerException
69 * @throws IllegalArgumentException
70 */
71 public Pam(String serviceName) throws NullPointerException, IllegalArgumentException {
72 if (serviceName == null) {
73 throw new NullPointerException("Service name is null");
74 } else if (serviceName.length() == 0) {
75 throw new IllegalArgumentException("Service name is empty");
76 }
77 this.serviceName = serviceName;
78 }
79
80 /***
81 * A simple way to check that JNI is installed and properly works
82 *
83 * @return true if working
84 */
85 native boolean isSharedLibraryWorking();
86
87 /***
88 * The {@link #isSharedLibraryWorking()} native method callsback to this method to make sure all is well.
89 */
90 private void callback() {
91 //noop
92 }
93
94 /***
95 * Authenticates a user.
96 * <p/>
97 * This method is threadsafe.
98 * <p/>
99 * If the logging toolkit is set to DEBUG, the shared library will emit debug
100 * information to the console.
101 *
102 * @param username the username to be authenticated
103 * @param credentials the credentials to use in the authentication .e.g a password
104 * @return true if the <code>PamReturnValue</code> is {@link PamReturnValue#PAM_SUCCESS}
105 */
106 public boolean authenticateSuccessful(String username, String credentials) {
107 PamReturnValue success = PamReturnValue.PAM_SUCCESS;
108 PamReturnValue actual = authenticate(username, credentials);
109 return actual.equals(success);
110 }
111
112 /***
113 * Sames as <code>authenticateSuccessful</code>, except a {@link PamReturnValue} is returned
114 * <p/>
115 * This method is threadsafe.
116 * @param username
117 * @param credentials
118 * @return a PAM specific return value
119 * @throws NullPointerException if any of the parameters are null
120 * @see #authenticateSuccessful(String, String)
121 */
122 public PamReturnValue authenticate(String username, String credentials) throws NullPointerException {
123 boolean debug = LOG.isDebugEnabled();
124 LOG.debug("Debug mode active.");
125 if (serviceName == null) {
126 throw new NullPointerException("Service name is null");
127 } else if (username == null) {
128 throw new NullPointerException("User name is null");
129 } else if (credentials == null) {
130 throw new NullPointerException("Credentials are null");
131 }
132 synchronized (Pam.class) {
133 PamReturnValue pamReturnValue = PamReturnValue.fromId(authenticate(serviceName, username, credentials, debug));
134 return pamReturnValue;
135 }
136 }
137
138
139 /***
140 * A main method
141 */
142 public static void main(String[] args) {
143 Pam pam = new Pam();
144 PamReturnValue pamReturnValue = pam.authenticate(args[0], args[1]);
145 System.out.println("Response: " + pamReturnValue);
146 }
147
148 /***
149 * Authenticates a user.
150 *
151 * Warning: Any calls to this method should be synchronized on the class. The underlying PAM mechanism is not
152 * threadsafe.
153 *
154 * @param serviceName the pam.d config file to use
155 * @param username the username to be authenticated
156 * @param credentials the credentials to be authenticated
157 * @param debug if true, debugging information will be emitted
158 * @return an integer, which can be converted to a {@link PamReturnValue} using {@link PamReturnValue#fromId(int)}
159 */
160 private native int authenticate(String serviceName, String username, String credentials, boolean debug);
161
162 /***
163 * @return the system dependent name of the shared library the Pam class is expecting.
164 */
165 public static String getLibraryName() {
166 return System.mapLibraryName(JPAM_SHARED_LIBRARY_NAME);
167 }
168
169
170 /***
171 * @return the servicename this PAM object is using
172 */
173 public String getServiceName() {
174 return serviceName;
175 }
176 }