YARN-2424. LCE should support non-cgroups, non-secure mode (Chris Douglas via aw)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1619421 13f79535-47bb-0310-9956-ffa450edef68

hadoop-yarn-project/CHANGES.txt

@@ -226,6 +226,9 @@ Release 2.6.0 - UNRELEASED
     YARN-1919. Potential NPE in EmbeddedElectorService#stop. 
     (Tsuyoshi Ozawa via kasha)
 
+    YARN-2424. LCE should support non-cgroups, non-secure mode (Chris Douglas 
+    via aw)
+
 Release 2.5.0 - 2014-08-11
 
   INCOMPATIBLE CHANGES

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/conf/YarnConfiguration.java

@@ -836,6 +836,15 @@ public class YarnConfiguration extends Configuration {
   public static final String NM_LINUX_CONTAINER_GROUP =
     NM_PREFIX + "linux-container-executor.group";
 
+  /**
+   * True if linux-container-executor should limit itself to one user
+   * when running in non-secure mode.
+   */
+  public static final String NM_NONSECURE_MODE_LIMIT_USERS = NM_PREFIX +
+     "linux-container-executor.nonsecure-mode.limit-users";
+
+  public static final boolean DEFAULT_NM_NONSECURE_MODE_LIMIT_USERS = true;
+
   /**
    * The UNIX user that containers will run as when Linux-container-executor
    * is used in nonsecure mode (a use case for this is using cgroups).

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

@@ -991,8 +991,22 @@
   </property>
 
   <property>
-    <description>The UNIX user that containers will run as when Linux-container-executor
-    is used in nonsecure mode (a use case for this is using cgroups).</description>
+    <description>This determines which of the two modes that LCE should use on
+      a non-secure cluster.  If this value is set to true, then all containers
+      will be launched as the user specified in
+      yarn.nodemanager.linux-container-executor.nonsecure-mode.local-user.  If
+      this value is set to false, then containers will run as the user who
+      submitted the application.</description>
+    <name>yarn.nodemanager.linux-container-executor.nonsecure-mode.limit-users</name>
+    <value>true</value>
+  </property>
+
+  <property>
+    <description>The UNIX user that containers will run as when
+      Linux-container-executor is used in nonsecure mode (a use case for this
+      is using cgroups) if the
+      yarn.nodemanager.linux-container-executor.nonsecure-mode.limit-users is
+      set to true.</description>
     <name>yarn.nodemanager.linux-container-executor.nonsecure-mode.local-user</name>
     <value>nobody</value>
   </property>

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/LinuxContainerExecutor.java

@@ -57,8 +57,8 @@ public class LinuxContainerExecutor extends ContainerExecutor {
   private LCEResourcesHandler resourcesHandler;
   private boolean containerSchedPriorityIsSet = false;
   private int containerSchedPriorityAdjustment = 0;
-  
-  
+  private boolean containerLimitUsers;
+
   @Override
   public void setConf(Configuration conf) {
     super.setConf(conf);
@@ -81,6 +81,13 @@ public class LinuxContainerExecutor extends ContainerExecutor {
     nonsecureLocalUserPattern = Pattern.compile(
         conf.get(YarnConfiguration.NM_NONSECURE_MODE_USER_PATTERN_KEY,
             YarnConfiguration.DEFAULT_NM_NONSECURE_MODE_USER_PATTERN));        
+    containerLimitUsers = conf.getBoolean(
+      YarnConfiguration.NM_NONSECURE_MODE_LIMIT_USERS,
+      YarnConfiguration.DEFAULT_NM_NONSECURE_MODE_LIMIT_USERS);
+    if (!containerLimitUsers) {
+      LOG.warn(YarnConfiguration.NM_NONSECURE_MODE_LIMIT_USERS +
+          ": impersonation without authentication enabled");
+    }
   }
 
   void verifyUsernamePattern(String user) {
@@ -92,7 +99,12 @@ public class LinuxContainerExecutor extends ContainerExecutor {
   }
 
   String getRunAsUser(String user) {
-    return UserGroupInformation.isSecurityEnabled() ? user : nonsecureLocalUser;
+    if (UserGroupInformation.isSecurityEnabled() ||
+       !containerLimitUsers) {
+      return user;
+    } else {
+      return nonsecureLocalUser;
+    }
   }
 
   /**

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/test/java/org/apache/hadoop/yarn/server/nodemanager/TestLinuxContainerExecutor.java

@@ -279,6 +279,13 @@ public class TestLinuxContainerExecutor {
       lce.setConf(conf);
       Assert.assertEquals("bar", lce.getRunAsUser("foo"));
 
+      //nonsecure without limits
+      conf.set(YarnConfiguration.NM_NONSECURE_MODE_LOCAL_USER_KEY, "bar");
+      conf.setBoolean(YarnConfiguration.NM_NONSECURE_MODE_LIMIT_USERS, false);
+      lce = new LinuxContainerExecutor();
+      lce.setConf(conf);
+      Assert.assertEquals("foo", lce.getRunAsUser("foo"));
+
       //secure
       conf = new YarnConfiguration();
       conf.set(CommonConfigurationKeysPublic.HADOOP_SECURITY_AUTHENTICATION,