replace portmapping FNV1-128 by FNV1-64 + Base64

[transportpce.git] / common / src / main / java / org / opendaylight / transportpce / common / mapping / PortMappingVersion221.java

diff --git a/common/src/main/java/org/opendaylight/transportpce/common/mapping/PortMappingVersion221.java b/common/src/main/java/org/opendaylight/transportpce/common/mapping/PortMappingVersion221.java
index a939b8ce6108802a1495493c8dcf007dcd554c6c..db21ac39744db588db8040682863eec5aae50a26 100644 (file)
--- a/common/src/main/java/org/opendaylight/transportpce/common/mapping/PortMappingVersion221.java
+++ b/common/src/main/java/org/opendaylight/transportpce/common/mapping/PortMappingVersion221.java
@@ -13,6 +13,7 @@ import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import java.math.BigInteger;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
+import java.util.Base64;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.HashMap;
@@ -91,10 +92,10 @@ public class PortMappingVersion221 {
     private final DataBroker dataBroker;
     private final DeviceTransactionManager deviceTransactionManager;
     private final OpenRoadmInterfaces openRoadmInterfaces;
-    //FNV1 128 bit hash constants
-    private static final BigInteger FNV_PRIME = new BigInteger("309485009821345068724781371");
-    private static final BigInteger FNV_INIT = new BigInteger("6c62272e07bb014262b821756295c58d", 16);
-    private static final BigInteger FNV_MOD = new BigInteger("2").pow(128);
+    //FNV1 64 bit hash constants
+    private static final BigInteger FNV_PRIME = new BigInteger("100000001b3", 16);
+    private static final BigInteger FNV_INIT = new BigInteger("cbf29ce484222325", 16);
+    private static final BigInteger FNV_MOD = new BigInteger("2").pow(64);
 
     public PortMappingVersion221(DataBroker dataBroker, DeviceTransactionManager deviceTransactionManager,
         OpenRoadmInterfaces openRoadmInterfaces) {
@@ -1019,7 +1020,9 @@ public class PortMappingVersion221 {
     }
 
     /**
-     * Implements the FNV-1 128bit algorithm.
+     * Implements the FNV-1 64bit algorithm.
+     * FNV-1 128bit would be ideal for 16 bytes but we need an overhead for Base64 encoding.
+     * Otherwise, the hash cannot be stored in a UTF-8 string.
      * https://www.wikiwand.com/en/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function#/FNV-1_hash
      * https://github.com/pmdamora/fnv-cracker-app/blob/master/src/main/java/passwordcrack/cracking/HashChecker.java
      * @param stringdata the String to be hashed
@@ -1034,6 +1037,6 @@ public class PortMappingVersion221 {
             hash = hash.xor(BigInteger.valueOf((int) b & 0xff));
         }
 
-        return hash.toString(16);
+        return Base64.getEncoder().encodeToString(hash.toByteArray());
     }
 }