From 0081b02e35306cb757c63d0f11a536941d73a139 Mon Sep 17 00:00:00 2001
From: Tsz Wo Nicholas Sze <szetszwo@apache.org>
Date: Thu, 29 Nov 2018 13:55:21 -0800
Subject: [PATCH] HDFS-14112. Avoid recursive call to external authorizer for
 getContentSummary.

---
 .../java/org/apache/hadoop/hdfs/DFSConfigKeys.java     |  4 ++++
 .../hdfs/server/namenode/FSDirStatAndListingOp.java    |  5 +++++
 .../hadoop/hdfs/server/namenode/FSDirectory.java       |  7 +++++++
 .../hadoop-hdfs/src/main/resources/hdfs-default.xml    | 10 ++++++++++
 4 files changed, 26 insertions(+)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java
index 3628b2b45e..5899c9297b 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java
@@ -284,6 +284,10 @@ public class DFSConfigKeys extends CommonConfigurationKeys {
       HdfsClientConfigKeys.DFS_WEBHDFS_USER_PATTERN_DEFAULT;
   public static final String  DFS_PERMISSIONS_ENABLED_KEY =
       HdfsClientConfigKeys.DeprecatedKeys.DFS_PERMISSIONS_ENABLED_KEY;
+  public static final String  DFS_PERMISSIONS_CONTENT_SUMMARY_SUBACCESS_KEY
+      = "dfs.permissions.ContentSummary.subAccess";
+  public static final boolean DFS_PERMISSIONS_CONTENT_SUMMARY_SUBACCESS_DEFAULT
+      = false;
   public static final boolean DFS_PERMISSIONS_ENABLED_DEFAULT = true;
   public static final String  DFS_PERMISSIONS_SUPERUSERGROUP_KEY =
       HdfsClientConfigKeys.DeprecatedKeys.DFS_PERMISSIONS_SUPERUSERGROUP_KEY;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirStatAndListingOp.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirStatAndListingOp.java
index 01de2360fa..052e522794 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirStatAndListingOp.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirStatAndListingOp.java
@@ -128,6 +128,11 @@ class FSDirStatAndListingOp {
   static ContentSummary getContentSummary(
       FSDirectory fsd, FSPermissionChecker pc, String src) throws IOException {
     final INodesInPath iip = fsd.resolvePath(pc, src, DirOp.READ_LINK);
+    if (fsd.isPermissionEnabled() && fsd.isPermissionContentSummarySubAccess()) {
+      fsd.checkPermission(pc, iip, false, null, null, null,
+          FsAction.READ_EXECUTE);
+      pc = null;
+    }
     // getContentSummaryInt() call will check access (if enabled) when
     // traversing all sub directories.
     return getContentSummaryInt(fsd, pc, iip);
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirectory.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirectory.java
index 712a327696..45f859c8ff 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirectory.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirectory.java
@@ -175,6 +175,7 @@ public class FSDirectory implements Closeable {
   private final ReentrantReadWriteLock dirLock;
 
   private final boolean isPermissionEnabled;
+  private final boolean isPermissionContentSummarySubAccess;
   /**
    * Support for ACLs is controlled by a configuration flag. If the
    * configuration flag is false, then the NameNode will reject all
@@ -274,6 +275,9 @@ public class FSDirectory implements Closeable {
     this.isPermissionEnabled = conf.getBoolean(
       DFSConfigKeys.DFS_PERMISSIONS_ENABLED_KEY,
       DFSConfigKeys.DFS_PERMISSIONS_ENABLED_DEFAULT);
+    this.isPermissionContentSummarySubAccess = conf.getBoolean(
+        DFSConfigKeys.DFS_PERMISSIONS_CONTENT_SUMMARY_SUBACCESS_KEY,
+        DFSConfigKeys.DFS_PERMISSIONS_CONTENT_SUMMARY_SUBACCESS_DEFAULT);
     this.fsOwnerShortUserName =
       UserGroupInformation.getCurrentUser().getShortUserName();
     this.supergroup = conf.get(
@@ -538,6 +542,9 @@ public class FSDirectory implements Closeable {
   boolean isAclsEnabled() {
     return aclsEnabled;
   }
+  boolean isPermissionContentSummarySubAccess() {
+    return isPermissionContentSummarySubAccess;
+  }
 
   @VisibleForTesting
   public boolean isPosixAclInheritanceEnabled() {
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml b/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
index c187a7d0ce..4e6c4db03d 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
@@ -469,6 +469,16 @@
   </description>
 </property>
 
+<property>
+  <name>dfs.permissions.ContentSummary.subAccess</name>
+  <value>false</value>
+  <description>
+    If "true", the ContentSummary permission checking will use subAccess.
+    If "false", the ContentSummary permission checking will NOT use subAccess.
+    subAccess means using recursion to check the access of all descendants.
+  </description>
+</property>
+
 <property>
   <name>dfs.permissions.superusergroup</name>
   <value>supergroup</value>