[SPARK-18547][CORE] Propagate I/O encryption key when executors register.

This change modifies the method used to propagate encryption keys used during
shuffle. Instead of relying on YARN's UserGroupInformation credential propagation,
this change explicitly distributes the key using the messages exchanged between
driver and executor during registration. When RPC encryption is enabled, this means
key propagation is also secure.

This allows shuffle encryption to work in non-YARN mode, which means that it's
easier to write unit tests for areas of the code that are affected by the feature.

The key is stored in the SecurityManager; because there are many instances of
that class used in the code, the key is only guaranteed to exist in the instance
managed by the SparkEnv. This path was chosen to avoid storing the key in the
SparkConf, which would risk having the key being written to disk as part of the
configuration (as, for example, is done when starting YARN applications).

Tested by new and existing unit tests (which were moved from the YARN module to
core), and by running apps with shuffle encryption enabled.

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #15981 from vanzin/SPARK-18547.

1 files changed, 0 insertions, 108 deletions

diff --git a/yarn/src/test/scala/org/apache/spark/deploy/yarn/IOEncryptionSuite.scala b/yarn/src/test/scala/org/apache/spark/deploy/yarn/IOEncryptionSuite.scala
deleted file mode 100644
index 1c60315b21..0000000000
--- a/yarn/src/test/scala/org/apache/spark/deploy/yarn/IOEncryptionSuite.scala
+++ /dev/null
@@ -1,108 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements.  See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License.  You may obtain a copy of the License at
- *
- *    http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.apache.spark.deploy.yarn
-
-import java.io._
-import java.nio.charset.StandardCharsets
-import java.security.PrivilegedExceptionAction
-import java.util.UUID
-
-import org.apache.hadoop.security.{Credentials, UserGroupInformation}
-import org.scalatest.{BeforeAndAfterAll, BeforeAndAfterEach, Matchers}
-
-import org.apache.spark._
-import org.apache.spark.deploy.SparkHadoopUtil
-import org.apache.spark.internal.config._
-import org.apache.spark.serializer._
-import org.apache.spark.storage._
-
-class IOEncryptionSuite extends SparkFunSuite with Matchers with BeforeAndAfterAll
-  with BeforeAndAfterEach {
-  private[this] val blockId = new TempShuffleBlockId(UUID.randomUUID())
-  private[this] val conf = new SparkConf()
-  private[this] val ugi = UserGroupInformation.createUserForTesting("testuser", Array("testgroup"))
-  private[this] val serializer = new KryoSerializer(conf)
-
-  override def beforeAll(): Unit = {
-    System.setProperty("SPARK_YARN_MODE", "true")
-    ugi.doAs(new PrivilegedExceptionAction[Unit]() {
-      override def run(): Unit = {
-        conf.set(IO_ENCRYPTION_ENABLED, true)
-        val creds = new Credentials()
-        SecurityManager.initIOEncryptionKey(conf, creds)
-        SparkHadoopUtil.get.addCurrentUserCredentials(creds)
-      }
-    })
-  }
-
-  override def afterAll(): Unit = {
-    SparkEnv.set(null)
-    System.clearProperty("SPARK_YARN_MODE")
-  }
-
-  override def beforeEach(): Unit = {
-    super.beforeEach()
-  }
-
-  override def afterEach(): Unit = {
-    super.afterEach()
-    conf.set("spark.shuffle.compress", false.toString)
-    conf.set("spark.shuffle.spill.compress", false.toString)
-  }
-
-  test("IO encryption read and write") {
-    ugi.doAs(new PrivilegedExceptionAction[Unit] {
-      override def run(): Unit = {
-        conf.set(IO_ENCRYPTION_ENABLED, true)
-        conf.set("spark.shuffle.compress", false.toString)
-        conf.set("spark.shuffle.spill.compress", false.toString)
-        testYarnIOEncryptionWriteRead()
-      }
-    })
-  }
-
-  test("IO encryption read and write with shuffle compression enabled") {
-    ugi.doAs(new PrivilegedExceptionAction[Unit] {
-      override def run(): Unit = {
-        conf.set(IO_ENCRYPTION_ENABLED, true)
-        conf.set("spark.shuffle.compress", true.toString)
-        conf.set("spark.shuffle.spill.compress", true.toString)
-        testYarnIOEncryptionWriteRead()
-      }
-    })
-  }
-
-  private[this] def testYarnIOEncryptionWriteRead(): Unit = {
-    val plainStr = "hello world"
-    val outputStream = new ByteArrayOutputStream()
-    val serializerManager = new SerializerManager(serializer, conf)
-    val wrappedOutputStream = serializerManager.wrapStream(blockId, outputStream)
-    wrappedOutputStream.write(plainStr.getBytes(StandardCharsets.UTF_8))
-    wrappedOutputStream.close()
-
-    val encryptedBytes = outputStream.toByteArray
-    val encryptedStr = new String(encryptedBytes)
-    assert(plainStr !== encryptedStr)
-
-    val inputStream = new ByteArrayInputStream(encryptedBytes)
-    val wrappedInputStream = serializerManager.wrapStream(blockId, inputStream)
-    val decryptedBytes = new Array[Byte](1024)
-    val len = wrappedInputStream.read(decryptedBytes)
-    val decryptedStr = new String(decryptedBytes, 0, len, StandardCharsets.UTF_8)
-    assert(decryptedStr === plainStr)
-  }
-}