001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018 package org.apache.hadoop.security;
019
020 import static org.apache.hadoop.fs.CommonConfigurationKeys.HADOOP_USER_GROUP_METRICS_PERCENTILES_INTERVALS;
021
022 import java.io.File;
023 import java.io.IOException;
024 import java.lang.reflect.UndeclaredThrowableException;
025 import java.security.AccessControlContext;
026 import java.security.AccessController;
027 import java.security.Principal;
028 import java.security.PrivilegedAction;
029 import java.security.PrivilegedActionException;
030 import java.security.PrivilegedExceptionAction;
031 import java.util.Arrays;
032 import java.util.Collection;
033 import java.util.Collections;
034 import java.util.HashMap;
035 import java.util.Iterator;
036 import java.util.List;
037 import java.util.Map;
038 import java.util.Set;
039
040 import javax.security.auth.Subject;
041 import javax.security.auth.callback.CallbackHandler;
042 import javax.security.auth.kerberos.KerberosKey;
043 import javax.security.auth.kerberos.KerberosPrincipal;
044 import javax.security.auth.kerberos.KerberosTicket;
045 import javax.security.auth.login.AppConfigurationEntry;
046 import javax.security.auth.login.LoginContext;
047 import javax.security.auth.login.LoginException;
048 import javax.security.auth.login.AppConfigurationEntry.LoginModuleControlFlag;
049 import javax.security.auth.spi.LoginModule;
050
051 import org.apache.commons.logging.Log;
052 import org.apache.commons.logging.LogFactory;
053 import org.apache.hadoop.classification.InterfaceAudience;
054 import org.apache.hadoop.classification.InterfaceStability;
055 import org.apache.hadoop.conf.Configuration;
056 import org.apache.hadoop.io.Text;
057 import org.apache.hadoop.metrics2.annotation.Metric;
058 import org.apache.hadoop.metrics2.annotation.Metrics;
059 import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
060 import org.apache.hadoop.metrics2.lib.MetricsRegistry;
061 import org.apache.hadoop.metrics2.lib.MutableQuantiles;
062 import org.apache.hadoop.metrics2.lib.MutableRate;
063 import org.apache.hadoop.security.SaslRpcServer.AuthMethod;
064 import org.apache.hadoop.security.authentication.util.KerberosUtil;
065 import org.apache.hadoop.security.token.Token;
066 import org.apache.hadoop.security.token.TokenIdentifier;
067 import org.apache.hadoop.util.Shell;
068 import org.apache.hadoop.util.Time;
069 import static org.apache.hadoop.util.PlatformName.IBM_JAVA;
070
071 import com.google.common.annotations.VisibleForTesting;
072
073 /**
074 * User and group information for Hadoop.
075 * This class wraps around a JAAS Subject and provides methods to determine the
076 * user's username and groups. It supports both the Windows, Unix and Kerberos
077 * login modules.
078 */
079 @InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce", "HBase", "Hive", "Oozie"})
080 @InterfaceStability.Evolving
081 public class UserGroupInformation {
082 private static final Log LOG = LogFactory.getLog(UserGroupInformation.class);
083 /**
084 * Percentage of the ticket window to use before we renew ticket.
085 */
086 private static final float TICKET_RENEW_WINDOW = 0.80f;
087 static final String HADOOP_USER_NAME = "HADOOP_USER_NAME";
088 static final String HADOOP_PROXY_USER = "HADOOP_PROXY_USER";
089
090 /**
091 * UgiMetrics maintains UGI activity statistics
092 * and publishes them through the metrics interfaces.
093 */
094 @Metrics(about="User and group related metrics", context="ugi")
095 static class UgiMetrics {
096 final MetricsRegistry registry = new MetricsRegistry("UgiMetrics");
097
098 @Metric("Rate of successful kerberos logins and latency (milliseconds)")
099 MutableRate loginSuccess;
100 @Metric("Rate of failed kerberos logins and latency (milliseconds)")
101 MutableRate loginFailure;
102 @Metric("GetGroups") MutableRate getGroups;
103 MutableQuantiles[] getGroupsQuantiles;
104
105 static UgiMetrics create() {
106 return DefaultMetricsSystem.instance().register(new UgiMetrics());
107 }
108
109 void addGetGroups(long latency) {
110 getGroups.add(latency);
111 if (getGroupsQuantiles != null) {
112 for (MutableQuantiles q : getGroupsQuantiles) {
113 q.add(latency);
114 }
115 }
116 }
117 }
118
119 /**
120 * A login module that looks at the Kerberos, Unix, or Windows principal and
121 * adds the corresponding UserName.
122 */
123 @InterfaceAudience.Private
124 public static class HadoopLoginModule implements LoginModule {
125 private Subject subject;
126
127 @Override
128 public boolean abort() throws LoginException {
129 return true;
130 }
131
132 private <T extends Principal> T getCanonicalUser(Class<T> cls) {
133 for(T user: subject.getPrincipals(cls)) {
134 return user;
135 }
136 return null;
137 }
138
139 @Override
140 public boolean commit() throws LoginException {
141 if (LOG.isDebugEnabled()) {
142 LOG.debug("hadoop login commit");
143 }
144 // if we already have a user, we are done.
145 if (!subject.getPrincipals(User.class).isEmpty()) {
146 if (LOG.isDebugEnabled()) {
147 LOG.debug("using existing subject:"+subject.getPrincipals());
148 }
149 return true;
150 }
151 Principal user = null;
152 // if we are using kerberos, try it out
153 if (isAuthenticationMethodEnabled(AuthenticationMethod.KERBEROS)) {
154 user = getCanonicalUser(KerberosPrincipal.class);
155 if (LOG.isDebugEnabled()) {
156 LOG.debug("using kerberos user:"+user);
157 }
158 }
159 //If we don't have a kerberos user and security is disabled, check
160 //if user is specified in the environment or properties
161 if (!isSecurityEnabled() && (user == null)) {
162 String envUser = System.getenv(HADOOP_USER_NAME);
163 if (envUser == null) {
164 envUser = System.getProperty(HADOOP_USER_NAME);
165 }
166 user = envUser == null ? null : new User(envUser);
167 }
168 // use the OS user
169 if (user == null) {
170 user = getCanonicalUser(OS_PRINCIPAL_CLASS);
171 if (LOG.isDebugEnabled()) {
172 LOG.debug("using local user:"+user);
173 }
174 }
175 // if we found the user, add our principal
176 if (user != null) {
177 subject.getPrincipals().add(new User(user.getName()));
178 return true;
179 }
180 LOG.error("Can't find user in " + subject);
181 throw new LoginException("Can't find user name");
182 }
183
184 @Override
185 public void initialize(Subject subject, CallbackHandler callbackHandler,
186 Map<String, ?> sharedState, Map<String, ?> options) {
187 this.subject = subject;
188 }
189
190 @Override
191 public boolean login() throws LoginException {
192 if (LOG.isDebugEnabled()) {
193 LOG.debug("hadoop login");
194 }
195 return true;
196 }
197
198 @Override
199 public boolean logout() throws LoginException {
200 if (LOG.isDebugEnabled()) {
201 LOG.debug("hadoop logout");
202 }
203 return true;
204 }
205 }
206
207 /** Metrics to track UGI activity */
208 static UgiMetrics metrics = UgiMetrics.create();
209 /** The auth method to use */
210 private static AuthenticationMethod authenticationMethod;
211 /** Server-side groups fetching service */
212 private static Groups groups;
213 /** The configuration to use */
214 private static Configuration conf;
215
216
217 /** Leave 10 minutes between relogin attempts. */
218 private static final long MIN_TIME_BEFORE_RELOGIN = 10 * 60 * 1000L;
219
220 /**Environment variable pointing to the token cache file*/
221 public static final String HADOOP_TOKEN_FILE_LOCATION =
222 "HADOOP_TOKEN_FILE_LOCATION";
223
224 /**
225 * A method to initialize the fields that depend on a configuration.
226 * Must be called before useKerberos or groups is used.
227 */
228 private static void ensureInitialized() {
229 if (conf == null) {
230 synchronized(UserGroupInformation.class) {
231 if (conf == null) { // someone might have beat us
232 initialize(new Configuration(), false);
233 }
234 }
235 }
236 }
237
238 /**
239 * Initialize UGI and related classes.
240 * @param conf the configuration to use
241 */
242 private static synchronized void initialize(Configuration conf,
243 boolean overrideNameRules) {
244 authenticationMethod = SecurityUtil.getAuthenticationMethod(conf);
245 if (overrideNameRules || !HadoopKerberosName.hasRulesBeenSet()) {
246 try {
247 HadoopKerberosName.setConfiguration(conf);
248 } catch (IOException ioe) {
249 throw new RuntimeException(
250 "Problem with Kerberos auth_to_local name configuration", ioe);
251 }
252 }
253 // If we haven't set up testing groups, use the configuration to find it
254 if (!(groups instanceof TestingGroups)) {
255 groups = Groups.getUserToGroupsMappingService(conf);
256 }
257 UserGroupInformation.conf = conf;
258
259 if (metrics.getGroupsQuantiles == null) {
260 int[] intervals = conf.getInts(HADOOP_USER_GROUP_METRICS_PERCENTILES_INTERVALS);
261 if (intervals != null && intervals.length > 0) {
262 final int length = intervals.length;
263 MutableQuantiles[] getGroupsQuantiles = new MutableQuantiles[length];
264 for (int i = 0; i < length; i++) {
265 getGroupsQuantiles[i] = metrics.registry.newQuantiles(
266 "getGroups" + intervals[i] + "s",
267 "Get groups", "ops", "latency", intervals[i]);
268 }
269 metrics.getGroupsQuantiles = getGroupsQuantiles;
270 }
271 }
272 }
273
274 /**
275 * Set the static configuration for UGI.
276 * In particular, set the security authentication mechanism and the
277 * group look up service.
278 * @param conf the configuration to use
279 */
280 @InterfaceAudience.Public
281 @InterfaceStability.Evolving
282 public static void setConfiguration(Configuration conf) {
283 initialize(conf, true);
284 }
285
286 @InterfaceAudience.Private
287 @VisibleForTesting
288 static void reset() {
289 authenticationMethod = null;
290 conf = null;
291 groups = null;
292 setLoginUser(null);
293 HadoopKerberosName.setRules(null);
294 }
295
296 /**
297 * Determine if UserGroupInformation is using Kerberos to determine
298 * user identities or is relying on simple authentication
299 *
300 * @return true if UGI is working in a secure environment
301 */
302 public static boolean isSecurityEnabled() {
303 return !isAuthenticationMethodEnabled(AuthenticationMethod.SIMPLE);
304 }
305
306 @InterfaceAudience.Private
307 @InterfaceStability.Evolving
308 private static boolean isAuthenticationMethodEnabled(AuthenticationMethod method) {
309 ensureInitialized();
310 return (authenticationMethod == method);
311 }
312
313 /**
314 * Information about the logged in user.
315 */
316 private static UserGroupInformation loginUser = null;
317 private static String keytabPrincipal = null;
318 private static String keytabFile = null;
319
320 private final Subject subject;
321 // All non-static fields must be read-only caches that come from the subject.
322 private final User user;
323 private final boolean isKeytab;
324 private final boolean isKrbTkt;
325
326 private static String OS_LOGIN_MODULE_NAME;
327 private static Class<? extends Principal> OS_PRINCIPAL_CLASS;
328
329 private static final boolean windows =
330 System.getProperty("os.name").startsWith("Windows");
331 private static final boolean is64Bit =
332 System.getProperty("os.arch").contains("64");
333 private static final boolean aix = System.getProperty("os.name").equals("AIX");
334
335 /* Return the OS login module class name */
336 private static String getOSLoginModuleName() {
337 if (IBM_JAVA) {
338 if (windows) {
339 return is64Bit ? "com.ibm.security.auth.module.Win64LoginModule"
340 : "com.ibm.security.auth.module.NTLoginModule";
341 } else if (aix) {
342 return is64Bit ? "com.ibm.security.auth.module.AIX64LoginModule"
343 : "com.ibm.security.auth.module.AIXLoginModule";
344 } else {
345 return "com.ibm.security.auth.module.LinuxLoginModule";
346 }
347 } else {
348 return windows ? "com.sun.security.auth.module.NTLoginModule"
349 : "com.sun.security.auth.module.UnixLoginModule";
350 }
351 }
352
353 /* Return the OS principal class */
354 @SuppressWarnings("unchecked")
355 private static Class<? extends Principal> getOsPrincipalClass() {
356 ClassLoader cl = ClassLoader.getSystemClassLoader();
357 try {
358 String principalClass = null;
359 if (IBM_JAVA) {
360 if (is64Bit) {
361 principalClass = "com.ibm.security.auth.UsernamePrincipal";
362 } else {
363 if (windows) {
364 principalClass = "com.ibm.security.auth.NTUserPrincipal";
365 } else if (aix) {
366 principalClass = "com.ibm.security.auth.AIXPrincipal";
367 } else {
368 principalClass = "com.ibm.security.auth.LinuxPrincipal";
369 }
370 }
371 } else {
372 principalClass = windows ? "com.sun.security.auth.NTUserPrincipal"
373 : "com.sun.security.auth.UnixPrincipal";
374 }
375 return (Class<? extends Principal>) cl.loadClass(principalClass);
376 } catch (ClassNotFoundException e) {
377 LOG.error("Unable to find JAAS classes:" + e.getMessage());
378 }
379 return null;
380 }
381 static {
382 OS_LOGIN_MODULE_NAME = getOSLoginModuleName();
383 OS_PRINCIPAL_CLASS = getOsPrincipalClass();
384 }
385
386 private static class RealUser implements Principal {
387 private final UserGroupInformation realUser;
388
389 RealUser(UserGroupInformation realUser) {
390 this.realUser = realUser;
391 }
392
393 @Override
394 public String getName() {
395 return realUser.getUserName();
396 }
397
398 public UserGroupInformation getRealUser() {
399 return realUser;
400 }
401
402 @Override
403 public boolean equals(Object o) {
404 if (this == o) {
405 return true;
406 } else if (o == null || getClass() != o.getClass()) {
407 return false;
408 } else {
409 return realUser.equals(((RealUser) o).realUser);
410 }
411 }
412
413 @Override
414 public int hashCode() {
415 return realUser.hashCode();
416 }
417
418 @Override
419 public String toString() {
420 return realUser.toString();
421 }
422 }
423
424 /**
425 * A JAAS configuration that defines the login modules that we want
426 * to use for login.
427 */
428 private static class HadoopConfiguration
429 extends javax.security.auth.login.Configuration {
430 private static final String SIMPLE_CONFIG_NAME = "hadoop-simple";
431 private static final String USER_KERBEROS_CONFIG_NAME =
432 "hadoop-user-kerberos";
433 private static final String KEYTAB_KERBEROS_CONFIG_NAME =
434 "hadoop-keytab-kerberos";
435
436 private static final Map<String, String> BASIC_JAAS_OPTIONS =
437 new HashMap<String,String>();
438 static {
439 String jaasEnvVar = System.getenv("HADOOP_JAAS_DEBUG");
440 if (jaasEnvVar != null && "true".equalsIgnoreCase(jaasEnvVar)) {
441 BASIC_JAAS_OPTIONS.put("debug", "true");
442 }
443 }
444
445 private static final AppConfigurationEntry OS_SPECIFIC_LOGIN =
446 new AppConfigurationEntry(OS_LOGIN_MODULE_NAME,
447 LoginModuleControlFlag.REQUIRED,
448 BASIC_JAAS_OPTIONS);
449 private static final AppConfigurationEntry HADOOP_LOGIN =
450 new AppConfigurationEntry(HadoopLoginModule.class.getName(),
451 LoginModuleControlFlag.REQUIRED,
452 BASIC_JAAS_OPTIONS);
453 private static final Map<String,String> USER_KERBEROS_OPTIONS =
454 new HashMap<String,String>();
455 static {
456 if (IBM_JAVA) {
457 USER_KERBEROS_OPTIONS.put("useDefaultCcache", "true");
458 } else {
459 USER_KERBEROS_OPTIONS.put("doNotPrompt", "true");
460 USER_KERBEROS_OPTIONS.put("useTicketCache", "true");
461 }
462 String ticketCache = System.getenv("KRB5CCNAME");
463 if (ticketCache != null) {
464 if (IBM_JAVA) {
465 // The first value searched when "useDefaultCcache" is used.
466 System.setProperty("KRB5CCNAME", ticketCache);
467 } else {
468 USER_KERBEROS_OPTIONS.put("ticketCache", ticketCache);
469 }
470 }
471 USER_KERBEROS_OPTIONS.put("renewTGT", "true");
472 USER_KERBEROS_OPTIONS.putAll(BASIC_JAAS_OPTIONS);
473 }
474 private static final AppConfigurationEntry USER_KERBEROS_LOGIN =
475 new AppConfigurationEntry(KerberosUtil.getKrb5LoginModuleName(),
476 LoginModuleControlFlag.OPTIONAL,
477 USER_KERBEROS_OPTIONS);
478 private static final Map<String,String> KEYTAB_KERBEROS_OPTIONS =
479 new HashMap<String,String>();
480 static {
481 if (IBM_JAVA) {
482 KEYTAB_KERBEROS_OPTIONS.put("credsType", "both");
483 } else {
484 KEYTAB_KERBEROS_OPTIONS.put("doNotPrompt", "true");
485 KEYTAB_KERBEROS_OPTIONS.put("useKeyTab", "true");
486 KEYTAB_KERBEROS_OPTIONS.put("storeKey", "true");
487 }
488 KEYTAB_KERBEROS_OPTIONS.put("refreshKrb5Config", "true");
489 KEYTAB_KERBEROS_OPTIONS.putAll(BASIC_JAAS_OPTIONS);
490 }
491 private static final AppConfigurationEntry KEYTAB_KERBEROS_LOGIN =
492 new AppConfigurationEntry(KerberosUtil.getKrb5LoginModuleName(),
493 LoginModuleControlFlag.REQUIRED,
494 KEYTAB_KERBEROS_OPTIONS);
495
496 private static final AppConfigurationEntry[] SIMPLE_CONF =
497 new AppConfigurationEntry[]{OS_SPECIFIC_LOGIN, HADOOP_LOGIN};
498
499 private static final AppConfigurationEntry[] USER_KERBEROS_CONF =
500 new AppConfigurationEntry[]{OS_SPECIFIC_LOGIN, USER_KERBEROS_LOGIN,
501 HADOOP_LOGIN};
502
503 private static final AppConfigurationEntry[] KEYTAB_KERBEROS_CONF =
504 new AppConfigurationEntry[]{KEYTAB_KERBEROS_LOGIN, HADOOP_LOGIN};
505
506 @Override
507 public AppConfigurationEntry[] getAppConfigurationEntry(String appName) {
508 if (SIMPLE_CONFIG_NAME.equals(appName)) {
509 return SIMPLE_CONF;
510 } else if (USER_KERBEROS_CONFIG_NAME.equals(appName)) {
511 return USER_KERBEROS_CONF;
512 } else if (KEYTAB_KERBEROS_CONFIG_NAME.equals(appName)) {
513 if (IBM_JAVA) {
514 KEYTAB_KERBEROS_OPTIONS.put("useKeytab",
515 prependFileAuthority(keytabFile));
516 } else {
517 KEYTAB_KERBEROS_OPTIONS.put("keyTab", keytabFile);
518 }
519 KEYTAB_KERBEROS_OPTIONS.put("principal", keytabPrincipal);
520 return KEYTAB_KERBEROS_CONF;
521 }
522 return null;
523 }
524 }
525
526 private static String prependFileAuthority(String keytabPath) {
527 return keytabPath.startsWith("file://") ? keytabPath
528 : "file://" + keytabPath;
529 }
530
531 /**
532 * Represents a javax.security configuration that is created at runtime.
533 */
534 private static class DynamicConfiguration
535 extends javax.security.auth.login.Configuration {
536 private AppConfigurationEntry[] ace;
537
538 DynamicConfiguration(AppConfigurationEntry[] ace) {
539 this.ace = ace;
540 }
541
542 @Override
543 public AppConfigurationEntry[] getAppConfigurationEntry(String appName) {
544 return ace;
545 }
546 }
547
548 private static LoginContext
549 newLoginContext(String appName, Subject subject,
550 javax.security.auth.login.Configuration loginConf)
551 throws LoginException {
552 // Temporarily switch the thread's ContextClassLoader to match this
553 // class's classloader, so that we can properly load HadoopLoginModule
554 // from the JAAS libraries.
555 Thread t = Thread.currentThread();
556 ClassLoader oldCCL = t.getContextClassLoader();
557 t.setContextClassLoader(HadoopLoginModule.class.getClassLoader());
558 try {
559 return new LoginContext(appName, subject, null, loginConf);
560 } finally {
561 t.setContextClassLoader(oldCCL);
562 }
563 }
564
565 private LoginContext getLogin() {
566 return user.getLogin();
567 }
568
569 private void setLogin(LoginContext login) {
570 user.setLogin(login);
571 }
572
573 /**
574 * Create a UserGroupInformation for the given subject.
575 * This does not change the subject or acquire new credentials.
576 * @param subject the user's subject
577 */
578 UserGroupInformation(Subject subject) {
579 this.subject = subject;
580 this.user = subject.getPrincipals(User.class).iterator().next();
581 this.isKeytab = !subject.getPrivateCredentials(KerberosKey.class).isEmpty();
582 this.isKrbTkt = !subject.getPrivateCredentials(KerberosTicket.class).isEmpty();
583 }
584
585 /**
586 * checks if logged in using kerberos
587 * @return true if the subject logged via keytab or has a Kerberos TGT
588 */
589 public boolean hasKerberosCredentials() {
590 return isKeytab || isKrbTkt;
591 }
592
593 /**
594 * Return the current user, including any doAs in the current stack.
595 * @return the current user
596 * @throws IOException if login fails
597 */
598 @InterfaceAudience.Public
599 @InterfaceStability.Evolving
600 public synchronized
601 static UserGroupInformation getCurrentUser() throws IOException {
602 AccessControlContext context = AccessController.getContext();
603 Subject subject = Subject.getSubject(context);
604 if (subject == null || subject.getPrincipals(User.class).isEmpty()) {
605 return getLoginUser();
606 } else {
607 return new UserGroupInformation(subject);
608 }
609 }
610
611 /**
612 * Find the most appropriate UserGroupInformation to use
613 *
614 * @param ticketCachePath The Kerberos ticket cache path, or NULL
615 * if none is specfied
616 * @param user The user name, or NULL if none is specified.
617 *
618 * @return The most appropriate UserGroupInformation
619 */
620 public static UserGroupInformation getBestUGI(
621 String ticketCachePath, String user) throws IOException {
622 if (ticketCachePath != null) {
623 return getUGIFromTicketCache(ticketCachePath, user);
624 } else if (user == null) {
625 return getCurrentUser();
626 } else {
627 return createRemoteUser(user);
628 }
629 }
630
631 /**
632 * Create a UserGroupInformation from a Kerberos ticket cache.
633 *
634 * @param user The principal name to load from the ticket
635 * cache
636 * @param ticketCachePath the path to the ticket cache file
637 *
638 * @throws IOException if the kerberos login fails
639 */
640 @InterfaceAudience.Public
641 @InterfaceStability.Evolving
642 public static UserGroupInformation getUGIFromTicketCache(
643 String ticketCache, String user) throws IOException {
644 if (!isAuthenticationMethodEnabled(AuthenticationMethod.KERBEROS)) {
645 return getBestUGI(null, user);
646 }
647 try {
648 Map<String,String> krbOptions = new HashMap<String,String>();
649 if (IBM_JAVA) {
650 krbOptions.put("useDefaultCcache", "true");
651 // The first value searched when "useDefaultCcache" is used.
652 System.setProperty("KRB5CCNAME", ticketCache);
653 } else {
654 krbOptions.put("doNotPrompt", "true");
655 krbOptions.put("useTicketCache", "true");
656 krbOptions.put("useKeyTab", "false");
657 krbOptions.put("ticketCache", ticketCache);
658 }
659 krbOptions.put("renewTGT", "false");
660 krbOptions.putAll(HadoopConfiguration.BASIC_JAAS_OPTIONS);
661 AppConfigurationEntry ace = new AppConfigurationEntry(
662 KerberosUtil.getKrb5LoginModuleName(),
663 LoginModuleControlFlag.REQUIRED,
664 krbOptions);
665 DynamicConfiguration dynConf =
666 new DynamicConfiguration(new AppConfigurationEntry[]{ ace });
667 LoginContext login = newLoginContext(
668 HadoopConfiguration.USER_KERBEROS_CONFIG_NAME, null, dynConf);
669 login.login();
670
671 Subject loginSubject = login.getSubject();
672 Set<Principal> loginPrincipals = loginSubject.getPrincipals();
673 if (loginPrincipals.isEmpty()) {
674 throw new RuntimeException("No login principals found!");
675 }
676 if (loginPrincipals.size() != 1) {
677 LOG.warn("found more than one principal in the ticket cache file " +
678 ticketCache);
679 }
680 User ugiUser = new User(loginPrincipals.iterator().next().getName(),
681 AuthenticationMethod.KERBEROS, login);
682 loginSubject.getPrincipals().add(ugiUser);
683 UserGroupInformation ugi = new UserGroupInformation(loginSubject);
684 ugi.setLogin(login);
685 ugi.setAuthenticationMethod(AuthenticationMethod.KERBEROS);
686 return ugi;
687 } catch (LoginException le) {
688 throw new IOException("failure to login using ticket cache file " +
689 ticketCache, le);
690 }
691 }
692
693 /**
694 * Get the currently logged in user.
695 * @return the logged in user
696 * @throws IOException if login fails
697 */
698 @InterfaceAudience.Public
699 @InterfaceStability.Evolving
700 public synchronized
701 static UserGroupInformation getLoginUser() throws IOException {
702 if (loginUser == null) {
703 loginUserFromSubject(null);
704 }
705 return loginUser;
706 }
707
708 /**
709 * Log in a user using the given subject
710 * @parma subject the subject to use when logging in a user, or null to
711 * create a new subject.
712 * @throws IOException if login fails
713 */
714 @InterfaceAudience.Public
715 @InterfaceStability.Evolving
716 public synchronized
717 static void loginUserFromSubject(Subject subject) throws IOException {
718 ensureInitialized();
719 try {
720 if (subject == null) {
721 subject = new Subject();
722 }
723 LoginContext login =
724 newLoginContext(authenticationMethod.getLoginAppName(),
725 subject, new HadoopConfiguration());
726 login.login();
727 UserGroupInformation realUser = new UserGroupInformation(subject);
728 realUser.setLogin(login);
729 realUser.setAuthenticationMethod(authenticationMethod);
730 realUser = new UserGroupInformation(login.getSubject());
731 // If the HADOOP_PROXY_USER environment variable or property
732 // is specified, create a proxy user as the logged in user.
733 String proxyUser = System.getenv(HADOOP_PROXY_USER);
734 if (proxyUser == null) {
735 proxyUser = System.getProperty(HADOOP_PROXY_USER);
736 }
737 loginUser = proxyUser == null ? realUser : createProxyUser(proxyUser, realUser);
738
739 String fileLocation = System.getenv(HADOOP_TOKEN_FILE_LOCATION);
740 if (fileLocation != null) {
741 // Load the token storage file and put all of the tokens into the
742 // user. Don't use the FileSystem API for reading since it has a lock
743 // cycle (HADOOP-9212).
744 Credentials cred = Credentials.readTokenStorageFile(
745 new File(fileLocation), conf);
746 loginUser.addCredentials(cred);
747 }
748 loginUser.spawnAutoRenewalThreadForUserCreds();
749 } catch (LoginException le) {
750 LOG.debug("failure to login", le);
751 throw new IOException("failure to login", le);
752 }
753 if (LOG.isDebugEnabled()) {
754 LOG.debug("UGI loginUser:"+loginUser);
755 }
756 }
757
758 @InterfaceAudience.Private
759 @InterfaceStability.Unstable
760 @VisibleForTesting
761 public synchronized static void setLoginUser(UserGroupInformation ugi) {
762 // if this is to become stable, should probably logout the currently
763 // logged in ugi if it's different
764 loginUser = ugi;
765 }
766
767 /**
768 * Is this user logged in from a keytab file?
769 * @return true if the credentials are from a keytab file.
770 */
771 public boolean isFromKeytab() {
772 return isKeytab;
773 }
774
775 /**
776 * Get the Kerberos TGT
777 * @return the user's TGT or null if none was found
778 */
779 private synchronized KerberosTicket getTGT() {
780 Set<KerberosTicket> tickets = subject
781 .getPrivateCredentials(KerberosTicket.class);
782 for (KerberosTicket ticket : tickets) {
783 if (SecurityUtil.isOriginalTGT(ticket)) {
784 if (LOG.isDebugEnabled()) {
785 LOG.debug("Found tgt " + ticket);
786 }
787 return ticket;
788 }
789 }
790 return null;
791 }
792
793 private long getRefreshTime(KerberosTicket tgt) {
794 long start = tgt.getStartTime().getTime();
795 long end = tgt.getEndTime().getTime();
796 return start + (long) ((end - start) * TICKET_RENEW_WINDOW);
797 }
798
799 /**Spawn a thread to do periodic renewals of kerberos credentials*/
800 private void spawnAutoRenewalThreadForUserCreds() {
801 if (isSecurityEnabled()) {
802 //spawn thread only if we have kerb credentials
803 if (user.getAuthenticationMethod() == AuthenticationMethod.KERBEROS &&
804 !isKeytab) {
805 Thread t = new Thread(new Runnable() {
806
807 @Override
808 public void run() {
809 String cmd = conf.get("hadoop.kerberos.kinit.command",
810 "kinit");
811 KerberosTicket tgt = getTGT();
812 if (tgt == null) {
813 return;
814 }
815 long nextRefresh = getRefreshTime(tgt);
816 while (true) {
817 try {
818 long now = Time.now();
819 if(LOG.isDebugEnabled()) {
820 LOG.debug("Current time is " + now);
821 LOG.debug("Next refresh is " + nextRefresh);
822 }
823 if (now < nextRefresh) {
824 Thread.sleep(nextRefresh - now);
825 }
826 Shell.execCommand(cmd, "-R");
827 if(LOG.isDebugEnabled()) {
828 LOG.debug("renewed ticket");
829 }
830 reloginFromTicketCache();
831 tgt = getTGT();
832 if (tgt == null) {
833 LOG.warn("No TGT after renewal. Aborting renew thread for " +
834 getUserName());
835 return;
836 }
837 nextRefresh = Math.max(getRefreshTime(tgt),
838 now + MIN_TIME_BEFORE_RELOGIN);
839 } catch (InterruptedException ie) {
840 LOG.warn("Terminating renewal thread");
841 return;
842 } catch (IOException ie) {
843 LOG.warn("Exception encountered while running the" +
844 " renewal command. Aborting renew thread. " + ie);
845 return;
846 }
847 }
848 }
849 });
850 t.setDaemon(true);
851 t.setName("TGT Renewer for " + getUserName());
852 t.start();
853 }
854 }
855 }
856 /**
857 * Log a user in from a keytab file. Loads a user identity from a keytab
858 * file and logs them in. They become the currently logged-in user.
859 * @param user the principal name to load from the keytab
860 * @param path the path to the keytab file
861 * @throws IOException if the keytab file can't be read
862 */
863 @InterfaceAudience.Public
864 @InterfaceStability.Evolving
865 public synchronized
866 static void loginUserFromKeytab(String user,
867 String path
868 ) throws IOException {
869 if (!isSecurityEnabled())
870 return;
871
872 keytabFile = path;
873 keytabPrincipal = user;
874 Subject subject = new Subject();
875 LoginContext login;
876 long start = 0;
877 try {
878 login = newLoginContext(HadoopConfiguration.KEYTAB_KERBEROS_CONFIG_NAME,
879 subject, new HadoopConfiguration());
880 start = Time.now();
881 login.login();
882 metrics.loginSuccess.add(Time.now() - start);
883 loginUser = new UserGroupInformation(subject);
884 loginUser.setLogin(login);
885 loginUser.setAuthenticationMethod(AuthenticationMethod.KERBEROS);
886 } catch (LoginException le) {
887 if (start > 0) {
888 metrics.loginFailure.add(Time.now() - start);
889 }
890 throw new IOException("Login failure for " + user + " from keytab " +
891 path, le);
892 }
893 LOG.info("Login successful for user " + keytabPrincipal
894 + " using keytab file " + keytabFile);
895 }
896
897 /**
898 * Re-login a user from keytab if TGT is expired or is close to expiry.
899 *
900 * @throws IOException
901 */
902 public synchronized void checkTGTAndReloginFromKeytab() throws IOException {
903 if (!isSecurityEnabled()
904 || user.getAuthenticationMethod() != AuthenticationMethod.KERBEROS
905 || !isKeytab)
906 return;
907 KerberosTicket tgt = getTGT();
908 if (tgt != null && Time.now() < getRefreshTime(tgt)) {
909 return;
910 }
911 reloginFromKeytab();
912 }
913
914 /**
915 * Re-Login a user in from a keytab file. Loads a user identity from a keytab
916 * file and logs them in. They become the currently logged-in user. This
917 * method assumes that {@link #loginUserFromKeytab(String, String)} had
918 * happened already.
919 * The Subject field of this UserGroupInformation object is updated to have
920 * the new credentials.
921 * @throws IOException on a failure
922 */
923 @InterfaceAudience.Public
924 @InterfaceStability.Evolving
925 public synchronized void reloginFromKeytab()
926 throws IOException {
927 if (!isSecurityEnabled() ||
928 user.getAuthenticationMethod() != AuthenticationMethod.KERBEROS ||
929 !isKeytab)
930 return;
931
932 long now = Time.now();
933 if (!hasSufficientTimeElapsed(now)) {
934 return;
935 }
936
937 KerberosTicket tgt = getTGT();
938 //Return if TGT is valid and is not going to expire soon.
939 if (tgt != null && now < getRefreshTime(tgt)) {
940 return;
941 }
942
943 LoginContext login = getLogin();
944 if (login == null || keytabFile == null) {
945 throw new IOException("loginUserFromKeyTab must be done first");
946 }
947
948 long start = 0;
949 // register most recent relogin attempt
950 user.setLastLogin(now);
951 try {
952 LOG.info("Initiating logout for " + getUserName());
953 synchronized (UserGroupInformation.class) {
954 // clear up the kerberos state. But the tokens are not cleared! As per
955 // the Java kerberos login module code, only the kerberos credentials
956 // are cleared
957 login.logout();
958 // login and also update the subject field of this instance to
959 // have the new credentials (pass it to the LoginContext constructor)
960 login = newLoginContext(
961 HadoopConfiguration.KEYTAB_KERBEROS_CONFIG_NAME, getSubject(),
962 new HadoopConfiguration());
963 LOG.info("Initiating re-login for " + keytabPrincipal);
964 start = Time.now();
965 login.login();
966 metrics.loginSuccess.add(Time.now() - start);
967 setLogin(login);
968 }
969 } catch (LoginException le) {
970 if (start > 0) {
971 metrics.loginFailure.add(Time.now() - start);
972 }
973 throw new IOException("Login failure for " + keytabPrincipal +
974 " from keytab " + keytabFile, le);
975 }
976 }
977
978 /**
979 * Re-Login a user in from the ticket cache. This
980 * method assumes that login had happened already.
981 * The Subject field of this UserGroupInformation object is updated to have
982 * the new credentials.
983 * @throws IOException on a failure
984 */
985 @InterfaceAudience.Public
986 @InterfaceStability.Evolving
987 public synchronized void reloginFromTicketCache()
988 throws IOException {
989 if (!isSecurityEnabled() ||
990 user.getAuthenticationMethod() != AuthenticationMethod.KERBEROS ||
991 !isKrbTkt)
992 return;
993 LoginContext login = getLogin();
994 if (login == null) {
995 throw new IOException("login must be done first");
996 }
997 long now = Time.now();
998 if (!hasSufficientTimeElapsed(now)) {
999 return;
1000 }
1001 // register most recent relogin attempt
1002 user.setLastLogin(now);
1003 try {
1004 LOG.info("Initiating logout for " + getUserName());
1005 //clear up the kerberos state. But the tokens are not cleared! As per
1006 //the Java kerberos login module code, only the kerberos credentials
1007 //are cleared
1008 login.logout();
1009 //login and also update the subject field of this instance to
1010 //have the new credentials (pass it to the LoginContext constructor)
1011 login =
1012 newLoginContext(HadoopConfiguration.USER_KERBEROS_CONFIG_NAME,
1013 getSubject(), new HadoopConfiguration());
1014 LOG.info("Initiating re-login for " + getUserName());
1015 login.login();
1016 setLogin(login);
1017 } catch (LoginException le) {
1018 throw new IOException("Login failure for " + getUserName(), le);
1019 }
1020 }
1021
1022
1023 /**
1024 * Log a user in from a keytab file. Loads a user identity from a keytab
1025 * file and login them in. This new user does not affect the currently
1026 * logged-in user.
1027 * @param user the principal name to load from the keytab
1028 * @param path the path to the keytab file
1029 * @throws IOException if the keytab file can't be read
1030 */
1031 public synchronized
1032 static UserGroupInformation loginUserFromKeytabAndReturnUGI(String user,
1033 String path
1034 ) throws IOException {
1035 if (!isSecurityEnabled())
1036 return UserGroupInformation.getCurrentUser();
1037 String oldKeytabFile = null;
1038 String oldKeytabPrincipal = null;
1039
1040 long start = 0;
1041 try {
1042 oldKeytabFile = keytabFile;
1043 oldKeytabPrincipal = keytabPrincipal;
1044 keytabFile = path;
1045 keytabPrincipal = user;
1046 Subject subject = new Subject();
1047
1048 LoginContext login = newLoginContext(
1049 HadoopConfiguration.KEYTAB_KERBEROS_CONFIG_NAME, subject,
1050 new HadoopConfiguration());
1051
1052 start = Time.now();
1053 login.login();
1054 metrics.loginSuccess.add(Time.now() - start);
1055 UserGroupInformation newLoginUser = new UserGroupInformation(subject);
1056 newLoginUser.setLogin(login);
1057 newLoginUser.setAuthenticationMethod(AuthenticationMethod.KERBEROS);
1058
1059 return newLoginUser;
1060 } catch (LoginException le) {
1061 if (start > 0) {
1062 metrics.loginFailure.add(Time.now() - start);
1063 }
1064 throw new IOException("Login failure for " + user + " from keytab " +
1065 path, le);
1066 } finally {
1067 if(oldKeytabFile != null) keytabFile = oldKeytabFile;
1068 if(oldKeytabPrincipal != null) keytabPrincipal = oldKeytabPrincipal;
1069 }
1070 }
1071
1072 private boolean hasSufficientTimeElapsed(long now) {
1073 if (now - user.getLastLogin() < MIN_TIME_BEFORE_RELOGIN ) {
1074 LOG.warn("Not attempting to re-login since the last re-login was " +
1075 "attempted less than " + (MIN_TIME_BEFORE_RELOGIN/1000) + " seconds"+
1076 " before.");
1077 return false;
1078 }
1079 return true;
1080 }
1081
1082 /**
1083 * Did the login happen via keytab
1084 * @return true or false
1085 */
1086 @InterfaceAudience.Public
1087 @InterfaceStability.Evolving
1088 public synchronized static boolean isLoginKeytabBased() throws IOException {
1089 return getLoginUser().isKeytab;
1090 }
1091
1092 /**
1093 * Create a user from a login name. It is intended to be used for remote
1094 * users in RPC, since it won't have any credentials.
1095 * @param user the full user principal name, must not be empty or null
1096 * @return the UserGroupInformation for the remote user.
1097 */
1098 @InterfaceAudience.Public
1099 @InterfaceStability.Evolving
1100 public static UserGroupInformation createRemoteUser(String user) {
1101 if (user == null || user.isEmpty()) {
1102 throw new IllegalArgumentException("Null user");
1103 }
1104 Subject subject = new Subject();
1105 subject.getPrincipals().add(new User(user));
1106 UserGroupInformation result = new UserGroupInformation(subject);
1107 result.setAuthenticationMethod(AuthenticationMethod.SIMPLE);
1108 return result;
1109 }
1110
1111 /**
1112 * existing types of authentications' methods
1113 */
1114 @InterfaceAudience.Public
1115 @InterfaceStability.Evolving
1116 public static enum AuthenticationMethod {
1117 // currently we support only one auth per method, but eventually a
1118 // subtype is needed to differentiate, ex. if digest is token or ldap
1119 SIMPLE(AuthMethod.SIMPLE,
1120 HadoopConfiguration.SIMPLE_CONFIG_NAME),
1121 KERBEROS(AuthMethod.KERBEROS,
1122 HadoopConfiguration.USER_KERBEROS_CONFIG_NAME),
1123 TOKEN(AuthMethod.TOKEN),
1124 CERTIFICATE(null),
1125 KERBEROS_SSL(null),
1126 PROXY(null);
1127
1128 private final AuthMethod authMethod;
1129 private final String loginAppName;
1130
1131 private AuthenticationMethod(AuthMethod authMethod) {
1132 this(authMethod, null);
1133 }
1134 private AuthenticationMethod(AuthMethod authMethod, String loginAppName) {
1135 this.authMethod = authMethod;
1136 this.loginAppName = loginAppName;
1137 }
1138
1139 public AuthMethod getAuthMethod() {
1140 return authMethod;
1141 }
1142
1143 String getLoginAppName() {
1144 if (loginAppName == null) {
1145 throw new UnsupportedOperationException(
1146 this + " login authentication is not supported");
1147 }
1148 return loginAppName;
1149 }
1150
1151 public static AuthenticationMethod valueOf(AuthMethod authMethod) {
1152 for (AuthenticationMethod value : values()) {
1153 if (value.getAuthMethod() == authMethod) {
1154 return value;
1155 }
1156 }
1157 throw new IllegalArgumentException(
1158 "no authentication method for " + authMethod);
1159 }
1160 };
1161
1162 /**
1163 * Create a proxy user using username of the effective user and the ugi of the
1164 * real user.
1165 * @param user
1166 * @param realUser
1167 * @return proxyUser ugi
1168 */
1169 @InterfaceAudience.Public
1170 @InterfaceStability.Evolving
1171 public static UserGroupInformation createProxyUser(String user,
1172 UserGroupInformation realUser) {
1173 if (user == null || user.isEmpty()) {
1174 throw new IllegalArgumentException("Null user");
1175 }
1176 if (realUser == null) {
1177 throw new IllegalArgumentException("Null real user");
1178 }
1179 Subject subject = new Subject();
1180 Set<Principal> principals = subject.getPrincipals();
1181 principals.add(new User(user));
1182 principals.add(new RealUser(realUser));
1183 UserGroupInformation result =new UserGroupInformation(subject);
1184 result.setAuthenticationMethod(AuthenticationMethod.PROXY);
1185 return result;
1186 }
1187
1188 /**
1189 * get RealUser (vs. EffectiveUser)
1190 * @return realUser running over proxy user
1191 */
1192 @InterfaceAudience.Public
1193 @InterfaceStability.Evolving
1194 public UserGroupInformation getRealUser() {
1195 for (RealUser p: subject.getPrincipals(RealUser.class)) {
1196 return p.getRealUser();
1197 }
1198 return null;
1199 }
1200
1201
1202
1203 /**
1204 * This class is used for storing the groups for testing. It stores a local
1205 * map that has the translation of usernames to groups.
1206 */
1207 private static class TestingGroups extends Groups {
1208 private final Map<String, List<String>> userToGroupsMapping =
1209 new HashMap<String,List<String>>();
1210 private Groups underlyingImplementation;
1211
1212 private TestingGroups(Groups underlyingImplementation) {
1213 super(new org.apache.hadoop.conf.Configuration());
1214 this.underlyingImplementation = underlyingImplementation;
1215 }
1216
1217 @Override
1218 public List<String> getGroups(String user) throws IOException {
1219 List<String> result = userToGroupsMapping.get(user);
1220
1221 if (result == null) {
1222 result = underlyingImplementation.getGroups(user);
1223 }
1224
1225 return result;
1226 }
1227
1228 private void setUserGroups(String user, String[] groups) {
1229 userToGroupsMapping.put(user, Arrays.asList(groups));
1230 }
1231 }
1232
1233 /**
1234 * Create a UGI for testing HDFS and MapReduce
1235 * @param user the full user principal name
1236 * @param userGroups the names of the groups that the user belongs to
1237 * @return a fake user for running unit tests
1238 */
1239 @InterfaceAudience.Public
1240 @InterfaceStability.Evolving
1241 public static UserGroupInformation createUserForTesting(String user,
1242 String[] userGroups) {
1243 ensureInitialized();
1244 UserGroupInformation ugi = createRemoteUser(user);
1245 // make sure that the testing object is setup
1246 if (!(groups instanceof TestingGroups)) {
1247 groups = new TestingGroups(groups);
1248 }
1249 // add the user groups
1250 ((TestingGroups) groups).setUserGroups(ugi.getShortUserName(), userGroups);
1251 return ugi;
1252 }
1253
1254
1255 /**
1256 * Create a proxy user UGI for testing HDFS and MapReduce
1257 *
1258 * @param user
1259 * the full user principal name for effective user
1260 * @param realUser
1261 * UGI of the real user
1262 * @param userGroups
1263 * the names of the groups that the user belongs to
1264 * @return a fake user for running unit tests
1265 */
1266 public static UserGroupInformation createProxyUserForTesting(String user,
1267 UserGroupInformation realUser, String[] userGroups) {
1268 ensureInitialized();
1269 UserGroupInformation ugi = createProxyUser(user, realUser);
1270 // make sure that the testing object is setup
1271 if (!(groups instanceof TestingGroups)) {
1272 groups = new TestingGroups(groups);
1273 }
1274 // add the user groups
1275 ((TestingGroups) groups).setUserGroups(ugi.getShortUserName(), userGroups);
1276 return ugi;
1277 }
1278
1279 /**
1280 * Get the user's login name.
1281 * @return the user's name up to the first '/' or '@'.
1282 */
1283 public String getShortUserName() {
1284 for (User p: subject.getPrincipals(User.class)) {
1285 return p.getShortName();
1286 }
1287 return null;
1288 }
1289
1290 public String getPrimaryGroupName() throws IOException {
1291 String[] groups = getGroupNames();
1292 if (groups.length == 0) {
1293 throw new IOException("There is no primary group for UGI " + this);
1294 }
1295 return groups[0];
1296 }
1297
1298 /**
1299 * Get the user's full principal name.
1300 * @return the user's full principal name.
1301 */
1302 @InterfaceAudience.Public
1303 @InterfaceStability.Evolving
1304 public String getUserName() {
1305 return user.getName();
1306 }
1307
1308 /**
1309 * Add a TokenIdentifier to this UGI. The TokenIdentifier has typically been
1310 * authenticated by the RPC layer as belonging to the user represented by this
1311 * UGI.
1312 *
1313 * @param tokenId
1314 * tokenIdentifier to be added
1315 * @return true on successful add of new tokenIdentifier
1316 */
1317 public synchronized boolean addTokenIdentifier(TokenIdentifier tokenId) {
1318 return subject.getPublicCredentials().add(tokenId);
1319 }
1320
1321 /**
1322 * Get the set of TokenIdentifiers belonging to this UGI
1323 *
1324 * @return the set of TokenIdentifiers belonging to this UGI
1325 */
1326 public synchronized Set<TokenIdentifier> getTokenIdentifiers() {
1327 return subject.getPublicCredentials(TokenIdentifier.class);
1328 }
1329
1330 /**
1331 * Add a token to this UGI
1332 *
1333 * @param token Token to be added
1334 * @return true on successful add of new token
1335 */
1336 public synchronized boolean addToken(Token<? extends TokenIdentifier> token) {
1337 return (token != null) ? addToken(token.getService(), token) : false;
1338 }
1339
1340 /**
1341 * Add a named token to this UGI
1342 *
1343 * @param alias Name of the token
1344 * @param token Token to be added
1345 * @return true on successful add of new token
1346 */
1347 public synchronized boolean addToken(Text alias,
1348 Token<? extends TokenIdentifier> token) {
1349 getCredentialsInternal().addToken(alias, token);
1350 return true;
1351 }
1352
1353 /**
1354 * Obtain the collection of tokens associated with this user.
1355 *
1356 * @return an unmodifiable collection of tokens associated with user
1357 */
1358 public synchronized
1359 Collection<Token<? extends TokenIdentifier>> getTokens() {
1360 return Collections.unmodifiableCollection(
1361 getCredentialsInternal().getAllTokens());
1362 }
1363
1364 /**
1365 * Obtain the tokens in credentials form associated with this user.
1366 *
1367 * @return Credentials of tokens associated with this user
1368 */
1369 public synchronized Credentials getCredentials() {
1370 Credentials creds = new Credentials(getCredentialsInternal());
1371 Iterator<Token<?>> iter = creds.getAllTokens().iterator();
1372 while (iter.hasNext()) {
1373 if (iter.next() instanceof Token.PrivateToken) {
1374 iter.remove();
1375 }
1376 }
1377 return creds;
1378 }
1379
1380 /**
1381 * Add the given Credentials to this user.
1382 * @param credentials of tokens and secrets
1383 */
1384 public synchronized void addCredentials(Credentials credentials) {
1385 getCredentialsInternal().addAll(credentials);
1386 }
1387
1388 private synchronized Credentials getCredentialsInternal() {
1389 final Credentials credentials;
1390 final Set<Credentials> credentialsSet =
1391 subject.getPrivateCredentials(Credentials.class);
1392 if (!credentialsSet.isEmpty()){
1393 credentials = credentialsSet.iterator().next();
1394 } else {
1395 credentials = new Credentials();
1396 subject.getPrivateCredentials().add(credentials);
1397 }
1398 return credentials;
1399 }
1400
1401 /**
1402 * Get the group names for this user.
1403 * @return the list of users with the primary group first. If the command
1404 * fails, it returns an empty list.
1405 */
1406 public synchronized String[] getGroupNames() {
1407 ensureInitialized();
1408 try {
1409 List<String> result = groups.getGroups(getShortUserName());
1410 return result.toArray(new String[result.size()]);
1411 } catch (IOException ie) {
1412 LOG.warn("No groups available for user " + getShortUserName());
1413 return new String[0];
1414 }
1415 }
1416
1417 /**
1418 * Return the username.
1419 */
1420 @Override
1421 public String toString() {
1422 StringBuilder sb = new StringBuilder(getUserName());
1423 sb.append(" (auth:"+getAuthenticationMethod()+")");
1424 if (getRealUser() != null) {
1425 sb.append(" via ").append(getRealUser().toString());
1426 }
1427 return sb.toString();
1428 }
1429
1430 /**
1431 * Sets the authentication method in the subject
1432 *
1433 * @param authMethod
1434 */
1435 public synchronized
1436 void setAuthenticationMethod(AuthenticationMethod authMethod) {
1437 user.setAuthenticationMethod(authMethod);
1438 }
1439
1440 /**
1441 * Sets the authentication method in the subject
1442 *
1443 * @param authMethod
1444 */
1445 public void setAuthenticationMethod(AuthMethod authMethod) {
1446 user.setAuthenticationMethod(AuthenticationMethod.valueOf(authMethod));
1447 }
1448
1449 /**
1450 * Get the authentication method from the subject
1451 *
1452 * @return AuthenticationMethod in the subject, null if not present.
1453 */
1454 public synchronized AuthenticationMethod getAuthenticationMethod() {
1455 return user.getAuthenticationMethod();
1456 }
1457
1458 /**
1459 * Get the authentication method from the real user's subject. If there
1460 * is no real user, return the given user's authentication method.
1461 *
1462 * @return AuthenticationMethod in the subject, null if not present.
1463 */
1464 public synchronized AuthenticationMethod getRealAuthenticationMethod() {
1465 UserGroupInformation ugi = getRealUser();
1466 if (ugi == null) {
1467 ugi = this;
1468 }
1469 return ugi.getAuthenticationMethod();
1470 }
1471
1472 /**
1473 * Returns the authentication method of a ugi. If the authentication method is
1474 * PROXY, returns the authentication method of the real user.
1475 *
1476 * @param ugi
1477 * @return AuthenticationMethod
1478 */
1479 public static AuthenticationMethod getRealAuthenticationMethod(
1480 UserGroupInformation ugi) {
1481 AuthenticationMethod authMethod = ugi.getAuthenticationMethod();
1482 if (authMethod == AuthenticationMethod.PROXY) {
1483 authMethod = ugi.getRealUser().getAuthenticationMethod();
1484 }
1485 return authMethod;
1486 }
1487
1488 /**
1489 * Compare the subjects to see if they are equal to each other.
1490 */
1491 @Override
1492 public boolean equals(Object o) {
1493 if (o == this) {
1494 return true;
1495 } else if (o == null || getClass() != o.getClass()) {
1496 return false;
1497 } else {
1498 return subject == ((UserGroupInformation) o).subject;
1499 }
1500 }
1501
1502 /**
1503 * Return the hash of the subject.
1504 */
1505 @Override
1506 public int hashCode() {
1507 return System.identityHashCode(subject);
1508 }
1509
1510 /**
1511 * Get the underlying subject from this ugi.
1512 * @return the subject that represents this user.
1513 */
1514 protected Subject getSubject() {
1515 return subject;
1516 }
1517
1518 /**
1519 * Run the given action as the user.
1520 * @param <T> the return type of the run method
1521 * @param action the method to execute
1522 * @return the value from the run method
1523 */
1524 @InterfaceAudience.Public
1525 @InterfaceStability.Evolving
1526 public <T> T doAs(PrivilegedAction<T> action) {
1527 logPrivilegedAction(subject, action);
1528 return Subject.doAs(subject, action);
1529 }
1530
1531 /**
1532 * Run the given action as the user, potentially throwing an exception.
1533 * @param <T> the return type of the run method
1534 * @param action the method to execute
1535 * @return the value from the run method
1536 * @throws IOException if the action throws an IOException
1537 * @throws Error if the action throws an Error
1538 * @throws RuntimeException if the action throws a RuntimeException
1539 * @throws InterruptedException if the action throws an InterruptedException
1540 * @throws UndeclaredThrowableException if the action throws something else
1541 */
1542 @InterfaceAudience.Public
1543 @InterfaceStability.Evolving
1544 public <T> T doAs(PrivilegedExceptionAction<T> action
1545 ) throws IOException, InterruptedException {
1546 try {
1547 logPrivilegedAction(subject, action);
1548 return Subject.doAs(subject, action);
1549 } catch (PrivilegedActionException pae) {
1550 Throwable cause = pae.getCause();
1551 LOG.warn("PriviledgedActionException as:"+this+" cause:"+cause);
1552 if (cause instanceof IOException) {
1553 throw (IOException) cause;
1554 } else if (cause instanceof Error) {
1555 throw (Error) cause;
1556 } else if (cause instanceof RuntimeException) {
1557 throw (RuntimeException) cause;
1558 } else if (cause instanceof InterruptedException) {
1559 throw (InterruptedException) cause;
1560 } else {
1561 throw new UndeclaredThrowableException(cause);
1562 }
1563 }
1564 }
1565
1566 private void logPrivilegedAction(Subject subject, Object action) {
1567 if (LOG.isDebugEnabled()) {
1568 // would be nice if action included a descriptive toString()
1569 String where = new Throwable().getStackTrace()[2].toString();
1570 LOG.debug("PrivilegedAction as:"+this+" from:"+where);
1571 }
1572 }
1573
1574 private void print() throws IOException {
1575 System.out.println("User: " + getUserName());
1576 System.out.print("Group Ids: ");
1577 System.out.println();
1578 String[] groups = getGroupNames();
1579 System.out.print("Groups: ");
1580 for(int i=0; i < groups.length; i++) {
1581 System.out.print(groups[i] + " ");
1582 }
1583 System.out.println();
1584 }
1585
1586 /**
1587 * A test method to print out the current user's UGI.
1588 * @param args if there are two arguments, read the user from the keytab
1589 * and print it out.
1590 * @throws Exception
1591 */
1592 public static void main(String [] args) throws Exception {
1593 System.out.println("Getting UGI for current user");
1594 UserGroupInformation ugi = getCurrentUser();
1595 ugi.print();
1596 System.out.println("UGI: " + ugi);
1597 System.out.println("Auth method " + ugi.user.getAuthenticationMethod());
1598 System.out.println("Keytab " + ugi.isKeytab);
1599 System.out.println("============================================================");
1600
1601 if (args.length == 2) {
1602 System.out.println("Getting UGI from keytab....");
1603 loginUserFromKeytab(args[0], args[1]);
1604 getCurrentUser().print();
1605 System.out.println("Keytab: " + ugi);
1606 System.out.println("Auth method " + loginUser.user.getAuthenticationMethod());
1607 System.out.println("Keytab " + loginUser.isKeytab);
1608 }
1609 }
1610
1611 }