HADOOP-7930. Kerberos relogin interval in UserGroupInformation should be configurable (xiaochen via rkanter)

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/CommonConfigurationKeysPublic.java

@@ -585,6 +585,12 @@ public class CommonConfigurationKeysPublic {
   /** Only used by HttpServer. */
   public static final boolean HADOOP_SSL_ENABLED_DEFAULT = false;
 
+  /** See <a href="{@docRoot}/../core-default.html">core-default.xml</a> */
+  public static final String HADOOP_KERBEROS_MIN_SECONDS_BEFORE_RELOGIN =
+      "hadoop.kerberos.min.seconds.before.relogin";
+  /** Default value for HADOOP_KERBEROS_MIN_SECONDS_BEFORE_RELOGIN */
+  public static final int HADOOP_KERBEROS_MIN_SECONDS_BEFORE_RELOGIN_DEFAULT =
+      60;
 
   // HTTP policies to be used in configuration
   // Use HttpPolicy.name() instead

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/UserGroupInformation.java

@@ -17,6 +17,8 @@
  */
 package org.apache.hadoop.security;
 
+import static org.apache.hadoop.fs.CommonConfigurationKeys.HADOOP_KERBEROS_MIN_SECONDS_BEFORE_RELOGIN;
+import static org.apache.hadoop.fs.CommonConfigurationKeys.HADOOP_KERBEROS_MIN_SECONDS_BEFORE_RELOGIN_DEFAULT;
 import static org.apache.hadoop.fs.CommonConfigurationKeys.HADOOP_USER_GROUP_METRICS_PERCENTILES_INTERVALS;
 import static org.apache.hadoop.fs.CommonConfigurationKeysPublic.HADOOP_TOKEN_FILES;
 import static org.apache.hadoop.security.UGIExceptionMessages.*;
@@ -253,13 +255,11 @@ public class UserGroupInformation {
   private static AuthenticationMethod authenticationMethod;
   /** Server-side groups fetching service */
   private static Groups groups;
+  /** Min time (in seconds) before relogin for Kerberos */
+  private static long kerberosMinSecondsBeforeRelogin;
   /** The configuration to use */
   private static Configuration conf;
 
-  
-  /** Leave 10 minutes between relogin attempts. */
-  private static final long MIN_TIME_BEFORE_RELOGIN = 10 * 60 * 1000L;
-  
   /**Environment variable pointing to the token cache file*/
   public static final String HADOOP_TOKEN_FILE_LOCATION = 
     "HADOOP_TOKEN_FILE_LOCATION";
@@ -293,6 +293,16 @@ public class UserGroupInformation {
             "Problem with Kerberos auth_to_local name configuration", ioe);
       }
     }
+    try {
+        kerberosMinSecondsBeforeRelogin = 1000L * conf.getLong(
+                HADOOP_KERBEROS_MIN_SECONDS_BEFORE_RELOGIN,
+                HADOOP_KERBEROS_MIN_SECONDS_BEFORE_RELOGIN_DEFAULT);
+    }
+    catch(NumberFormatException nfe) {
+        throw new IllegalArgumentException("Invalid attribute value for " +
+                HADOOP_KERBEROS_MIN_SECONDS_BEFORE_RELOGIN + " of " +
+                conf.get(HADOOP_KERBEROS_MIN_SECONDS_BEFORE_RELOGIN));
+    }
     // If we haven't set up testing groups, use the configuration to find it
     if (!(groups instanceof TestingGroups)) {
       groups = Groups.getUserToGroupsMappingService(conf);
@@ -973,7 +983,7 @@ public class UserGroupInformation {
               return;
             }
             nextRefresh = Math.max(getRefreshTime(tgt),
-              now + MIN_TIME_BEFORE_RELOGIN);
+              now + kerberosMinSecondsBeforeRelogin);
           } catch (InterruptedException ie) {
             LOG.warn("Terminating renewal thread");
             return;
@@ -1265,10 +1275,10 @@ public class UserGroupInformation {
   }
 
   private boolean hasSufficientTimeElapsed(long now) {
-    if (now - user.getLastLogin() < MIN_TIME_BEFORE_RELOGIN ) {
+    if (now - user.getLastLogin() < kerberosMinSecondsBeforeRelogin ) {
       LOG.warn("Not attempting to re-login since the last re-login was " +
-          "attempted less than " + (MIN_TIME_BEFORE_RELOGIN/1000) + " seconds"+
-          " before. Last Login=" + user.getLastLogin());
+          "attempted less than " + (kerberosMinSecondsBeforeRelogin/1000) +
+          " seconds before. Last Login=" + user.getLastLogin());
       return false;
     }
     return true;

hadoop-common-project/hadoop-common/src/main/resources/core-default.xml

@@ -546,6 +546,14 @@
   </description>
 </property>
 
+<property>
+    <name>hadoop.kerberos.min.seconds.before.relogin</name>
+    <value>60</value>
+    <description>The minimum time between relogin attempts for Kerberos, in
+    seconds.
+    </description>
+</property>
+
 <property>
   <name>hadoop.security.auth_to_local</name>
   <value></value>

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/security/TestUserGroupInformation.java

@@ -40,6 +40,7 @@ import java.io.BufferedReader;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStreamReader;
+import java.lang.reflect.Method;
 import java.security.PrivilegedExceptionAction;
 import java.util.Collection;
 import java.util.ConcurrentModificationException;
@@ -975,4 +976,39 @@ public class TestUserGroupInformation {
     });
 
   }
+
+  /** Test hasSufficientTimeElapsed method */
+  @Test
+  public void testHasSufficientTimeElapsed() throws Exception {
+    // Make hasSufficientTimeElapsed public
+    Method method = UserGroupInformation.class
+            .getDeclaredMethod("hasSufficientTimeElapsed", long.class);
+    method.setAccessible(true);
+
+    UserGroupInformation ugi = UserGroupInformation.getCurrentUser();
+    User user = ugi.getSubject().getPrincipals(User.class).iterator().next();
+    long now = System.currentTimeMillis();
+
+    // Using default relogin time (1 minute)
+    user.setLastLogin(now - 2 * 60 * 1000);  // 2 minutes before "now"
+    assertTrue((Boolean)method.invoke(ugi, now));
+    user.setLastLogin(now - 30 * 1000);      // 30 seconds before "now"
+    assertFalse((Boolean)method.invoke(ugi, now));
+
+    // Using relogin time of 10 minutes
+    Configuration conf2 = new Configuration(conf);
+    conf2.setLong(
+       CommonConfigurationKeysPublic.HADOOP_KERBEROS_MIN_SECONDS_BEFORE_RELOGIN,
+       10 * 60);
+    UserGroupInformation.setConfiguration(conf2);
+    user.setLastLogin(now - 15 * 60 * 1000); // 15 minutes before "now"
+    assertTrue((Boolean)method.invoke(ugi, now));
+    user.setLastLogin(now - 6 * 60 * 1000);  // 6 minutes before "now"
+    assertFalse((Boolean)method.invoke(ugi, now));
+    // Restore original conf to UGI
+    UserGroupInformation.setConfiguration(conf);
+
+    // Restore hasSufficientTimElapsed back to private
+    method.setAccessible(false);
+  }
 }