HADOOP-12716. KerberosAuthenticator#doSpnegoSequence use incorrect class to determine isKeyTab in JDK8. Contributed by Xiaoyu Yao.

hadoop-common-project/hadoop-auth/src/main/java/org/apache/hadoop/security/authentication/client/KerberosAuthenticator.java

@@ -24,8 +24,6 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import javax.security.auth.Subject;
-import javax.security.auth.kerberos.KerberosKey;
-import javax.security.auth.kerberos.KerberosTicket;
 import javax.security.auth.login.AppConfigurationEntry;
 import javax.security.auth.login.Configuration;
 import javax.security.auth.login.LoginContext;
@@ -272,8 +270,8 @@ public class KerberosAuthenticator implements Authenticator {
       AccessControlContext context = AccessController.getContext();
       Subject subject = Subject.getSubject(context);
       if (subject == null
-          || (subject.getPrivateCredentials(KerberosKey.class).isEmpty()
-              && subject.getPrivateCredentials(KerberosTicket.class).isEmpty())) {
+          || (!KerberosUtil.hasKerberosKeyTab(subject)
+              && !KerberosUtil.hasKerberosTicket(subject))) {
         LOG.debug("No subject in context, logging in");
         subject = new Subject();
         LoginContext login = new LoginContext("", subject,

hadoop-common-project/hadoop-auth/src/main/java/org/apache/hadoop/security/authentication/util/KerberosUtil.java

@@ -38,6 +38,10 @@ import org.apache.directory.server.kerberos.shared.keytab.KeytabEntry;
 import org.ietf.jgss.GSSException;
 import org.ietf.jgss.Oid;
 
+import javax.security.auth.Subject;
+import javax.security.auth.kerberos.KerberosTicket;
+import javax.security.auth.kerberos.KeyTab;
+
 public class KerberosUtil {
 
   /* Return the Kerberos login module name */
@@ -227,4 +231,28 @@ public class KerberosUtil {
     }
     return principals;
   }
+
+  /**
+   * Check if the subject contains Kerberos keytab related objects.
+   * The Kerberos keytab object attached in subject has been changed
+   * from KerberosKey (JDK 7) to KeyTab (JDK 8)
+   *
+   *
+   * @param subject subject to be checked
+   * @return true if the subject contains Kerberos keytab
+   */
+  public static boolean hasKerberosKeyTab(Subject subject) {
+    return !subject.getPrivateCredentials(KeyTab.class).isEmpty();
+  }
+
+  /**
+   * Check if the subject contains Kerberos ticket.
+   *
+   *
+   * @param subject subject to be checked
+   * @return true if the subject contains Kerberos ticket
+   */
+  public static boolean hasKerberosTicket(Subject subject) {
+    return !subject.getPrivateCredentials(KerberosTicket.class).isEmpty();
+  }
 }

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -1744,6 +1744,9 @@ Release 2.8.0 - UNRELEASED
 
     HADOOP-12878. KMS SPNEGO sequence does not work with WEBHDFS. (xyao)
 
+    HADOOP-12716. KerberosAuthenticator#doSpnegoSequence use incorrect class to
+    determine isKeyTab in JDK8. (Xiaoyu Yao via cnauroth)
+
 Release 2.7.3 - UNRELEASED
 
   INCOMPATIBLE CHANGES

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

@@ -48,7 +48,6 @@ import javax.security.auth.Subject;
 import javax.security.auth.callback.CallbackHandler;
 import javax.security.auth.kerberos.KerberosPrincipal;
 import javax.security.auth.kerberos.KerberosTicket;
-import javax.security.auth.kerberos.KeyTab;
 import javax.security.auth.login.AppConfigurationEntry;
 import javax.security.auth.login.AppConfigurationEntry.LoginModuleControlFlag;
 import javax.security.auth.login.LoginContext;
@@ -624,8 +623,8 @@ public class UserGroupInformation {
   UserGroupInformation(Subject subject) {
     this.subject = subject;
     this.user = subject.getPrincipals(User.class).iterator().next();
-    this.isKeytab = !subject.getPrivateCredentials(KeyTab.class).isEmpty();
-    this.isKrbTkt = !subject.getPrivateCredentials(KerberosTicket.class).isEmpty();
+    this.isKeytab = KerberosUtil.hasKerberosKeyTab(subject);
+    this.isKrbTkt = KerberosUtil.hasKerberosTicket(subject);
   }
   
   /**