HADOOP-18329. Support for IBM Semeru JVM > 11.0.15.0 Vendor Name Changes (#4537) (#5208)

The static boolean PlatformName.IBM_JAVA now identifies
Java 11+ IBM Semeru runtimes as IBM JVM releases.

Contributed by Jack Buggins.

hadoop-common-project/hadoop-auth/src/main/java/org/apache/hadoop/util/PlatformName.java

@@ -18,6 +18,10 @@
 
 package org.apache.hadoop.util;
 
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+import java.util.Arrays;
+
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 
@@ -33,10 +37,10 @@ public class PlatformName {
    * per the java-vm.
    */
   public static final String PLATFORM_NAME =
-      (System.getProperty("os.name").startsWith("Windows")
-      ? System.getenv("os") : System.getProperty("os.name"))
-      + "-" + System.getProperty("os.arch")
-      + "-" + System.getProperty("sun.arch.data.model");
+      (System.getProperty("os.name").startsWith("Windows") ?
+      System.getenv("os") : System.getProperty("os.name"))
+      + "-" + System.getProperty("os.arch") + "-"
+      + System.getProperty("sun.arch.data.model");
 
   /**
    * The java vendor name used in this platform.
@@ -44,10 +48,60 @@ public class PlatformName {
   public static final String JAVA_VENDOR_NAME = System.getProperty("java.vendor");
 
   /**
-   * A public static variable to indicate the current java vendor is
-   * IBM java or not.
+   * Define a system class accessor that is open to changes in underlying implementations
+   * of the system class loader modules.
    */
-  public static final boolean IBM_JAVA = JAVA_VENDOR_NAME.contains("IBM");
+  private static final class SystemClassAccessor extends ClassLoader {
+    public Class<?> getSystemClass(String className) throws ClassNotFoundException {
+      return findSystemClass(className);
+    }
+  }
+
+  /**
+   * A public static variable to indicate the current java vendor is
+   * IBM and the type is Java Technology Edition which provides its
+   * own implementations of many security packages and Cipher suites.
+   * Note that these are not provided in Semeru runtimes:
+   * See https://developer.ibm.com/languages/java/semeru-runtimes for details.
+   */
+  public static final boolean IBM_JAVA = JAVA_VENDOR_NAME.contains("IBM") &&
+      hasIbmTechnologyEditionModules();
+
+  private static boolean hasIbmTechnologyEditionModules() {
+    return Arrays.asList(
+        "com.ibm.security.auth.module.JAASLoginModule",
+        "com.ibm.security.auth.module.Win64LoginModule",
+        "com.ibm.security.auth.module.NTLoginModule",
+        "com.ibm.security.auth.module.AIX64LoginModule",
+        "com.ibm.security.auth.module.LinuxLoginModule",
+        "com.ibm.security.auth.module.Krb5LoginModule"
+    ).stream().anyMatch((module) -> isSystemClassAvailable(module));
+  }
+
+  /**
+   * In rare cases where different behaviour is performed based on the JVM vendor
+   * this method should be used to test for a unique JVM class provided by the
+   * vendor rather than using the vendor method. For example if on JVM provides a
+   * different Kerberos login module testing for that login module being loadable
+   * before configuring to use it is preferable to using the vendor data.
+   *
+   * @param className the name of a class in the JVM to test for
+   * @return true if the class is available, false otherwise.
+   */
+  private static boolean isSystemClassAvailable(String className) {
+    return AccessController.doPrivileged((PrivilegedAction<Boolean>) () -> {
+      try {
+        // Using ClassLoader.findSystemClass() instead of
+        // Class.forName(className, false, null) because Class.forName with a null
+        // ClassLoader only looks at the boot ClassLoader with Java 9 and above
+        // which doesn't look at all the modules available to the findSystemClass.
+        new SystemClassAccessor().getSystemClass(className);
+        return true;
+      } catch (Exception ignored) {
+        return false;
+      }
+    });
+  }
 
   public static void main(String[] args) {
     System.out.println(PLATFORM_NAME);

hadoop-common-project/hadoop-minikdc/src/test/java/org/apache/hadoop/minikdc/TestMiniKdc.java

@@ -38,8 +38,35 @@ import java.util.HashMap;
 import java.util.Arrays;
 
 public class TestMiniKdc extends KerberosSecurityTestcase {
-  private static final boolean IBM_JAVA = System.getProperty("java.vendor")
-      .contains("IBM");
+  private static final boolean IBM_JAVA = shouldUseIbmPackages();
+  // duplicated to avoid cycles in the build
+  private static boolean shouldUseIbmPackages() {
+    final List<String> ibmTechnologyEditionSecurityModules = Arrays.asList(
+        "com.ibm.security.auth.module.JAASLoginModule",
+        "com.ibm.security.auth.module.Win64LoginModule",
+        "com.ibm.security.auth.module.NTLoginModule",
+        "com.ibm.security.auth.module.AIX64LoginModule",
+        "com.ibm.security.auth.module.LinuxLoginModule",
+        "com.ibm.security.auth.module.Krb5LoginModule"
+    );
+
+    if (System.getProperty("java.vendor").contains("IBM")) {
+      return ibmTechnologyEditionSecurityModules
+          .stream().anyMatch((module) -> isSystemClassAvailable(module));
+    }
+
+    return false;
+  }
+
+  private static boolean isSystemClassAvailable(String className) {
+    try {
+      Class.forName(className);
+      return true;
+    } catch (Exception ignored) {
+      return false;
+    }
+  }
+
   @Test
   public void testMiniKdcStart() {
     MiniKdc kdc = getKdc();