HDFS-14305. Fix serial number calculation in BlockTokenSecretManager to avoid token key ID overlap between NameNodes. Contributed by Konstantin V Shvachko.

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/security/token/block/BlockTokenSecretManager.java

@@ -116,8 +116,6 @@ public class BlockTokenSecretManager extends
         encryptionAlgorithm, nnIndex, numNNs, shouldWrapQOP);
     Preconditions.checkArgument(nnIndex >= 0);
     Preconditions.checkArgument(numNNs > 0);
-    setSerialNo(new SecureRandom().nextInt());
-    generateKeys();
   }
 
   public BlockTokenSecretManager(long keyUpdateInterval,
@@ -140,13 +138,19 @@ public class BlockTokenSecretManager extends
     this.encryptionAlgorithm = encryptionAlgorithm;
     this.shouldWrapQOP = shouldWrapQOP;
     this.timer = new Timer();
+    setSerialNo(new SecureRandom().nextInt(Integer.MAX_VALUE));
+    LOG.info("Block token key range: [" +
+        nnRangeStart + ", " + (nnRangeStart + intRange) + ")");
     generateKeys();
   }
   
   @VisibleForTesting
-  public synchronized void setSerialNo(int serialNo) {
+  public synchronized void setSerialNo(int nextNo) {
     // we mod the serial number by the range and then add that times the index
-    this.serialNo = (serialNo % intRange) + (nnRangeStart);
+    this.serialNo = (nextNo % intRange) + (nnRangeStart);
+    assert serialNo >= nnRangeStart && serialNo < (nnRangeStart + intRange) :
+      "serialNo " + serialNo + " is not in the designated range: [" +
+      nnRangeStart + ", " + (nnRangeStart + intRange) + ")";
   }
   
   public void setBlockPoolId(String blockPoolId) {

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/security/token/block/TestBlockToken.java

@@ -411,4 +411,28 @@ public class TestBlockToken {
       cluster.shutdown();
     }
   }
+
+  /**
+   * Verify that block token serialNo is always within the range designated to
+   * to the NameNode.
+   */
+  @Test
+  public void testBlockTokenRanges() throws IOException {
+    final int interval = 1024;
+    final int numNNs = Integer.MAX_VALUE / interval;
+    for(int nnIdx = 0; nnIdx < 64; nnIdx++) {
+      BlockTokenSecretManager sm = new BlockTokenSecretManager(
+          blockKeyUpdateInterval, blockTokenLifetime, nnIdx, numNNs,
+          "fake-pool", null, false);
+      int rangeStart = nnIdx * interval;
+      for(int i = 0; i < interval * 3; i++) {
+        int serialNo = sm.getSerialNoForTesting();
+        assertTrue(
+            "serialNo " + serialNo + " is not in the designated range: [" +
+                rangeStart + ", " + (rangeStart + interval) + ")",
+                serialNo >= rangeStart && serialNo < (rangeStart + interval));
+        sm.updateKeys();
+      }
+    }
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestFailoverWithBlockTokensEnabled.java

@@ -92,11 +92,10 @@ public class TestFailoverWithBlockTokensEnabled {
 
     setAndCheckSerialNumber(0, btsm1, btsm2, btsm3);
     setAndCheckSerialNumber(Integer.MAX_VALUE, btsm1, btsm2, btsm3);
-    setAndCheckSerialNumber(Integer.MIN_VALUE, btsm1, btsm2, btsm3);
     setAndCheckSerialNumber(Integer.MAX_VALUE / 2, btsm1, btsm2, btsm3);
-    setAndCheckSerialNumber(Integer.MIN_VALUE / 2, btsm1, btsm2, btsm3);
     setAndCheckSerialNumber(Integer.MAX_VALUE / 3, btsm1, btsm2, btsm3);
-    setAndCheckSerialNumber(Integer.MIN_VALUE / 3, btsm1, btsm2, btsm3);
+    setAndCheckSerialNumber(Integer.MAX_VALUE / 171717,
+        btsm1, btsm2, btsm3);
   }
 
   private void setAndCheckSerialNumber(int serialNumber, BlockTokenSecretManager... btsms) {