Safely paralelizes signature verification from different clients to exploit multicore machines.

src/navigators/smart/clientsmanagement/ClientData.java

@@ -18,11 +18,14 @@
 
 package navigators.smart.clientsmanagement;
 
+import java.security.PublicKey;
+import java.security.Signature;
+import java.security.SignatureException;
 import java.util.Iterator;
 import java.util.concurrent.locks.ReentrantLock;
 
-import navigators.smart.reconfiguration.ReconfigurationManager;
 import navigators.smart.tom.core.messages.TOMMessage;
+import navigators.smart.tom.util.Logger;
 import navigators.smart.tom.util.TOMUtil;
 
 public class ClientData {
@@ -43,15 +46,26 @@ public class ClientData {
 
     private TOMMessage lastReplySent = null;
 
-    private ReconfigurationManager manager;
+    private Signature signatureVerificator = null;
+
     /**
-     * Class constructor. Just store the clientId.
+     * Class constructor. Just store the clientId and creates a signature
+     * verificator for a given client public key.
      *
-     * @param clientId
+     * @param clientId client unique id
+     * @param publicKey client public key
      */
-    public ClientData(int clientId, ReconfigurationManager manager) {
+    public ClientData(int clientId, PublicKey publicKey) {
         this.clientId = clientId;
-        this.manager = manager;
+        if(publicKey != null) {
+            try {
+                signatureVerificator = Signature.getInstance("SHA1withRSA");
+                signatureVerificator.initVerify(publicKey);
+                Logger.println("Signature verifier initialized for client "+clientId);
+            } catch (Exception ex) {
+                ex.printStackTrace();
+            }
+        }
     }
 
     public int getClientId() {
@@ -79,12 +93,14 @@ public class ClientData {
     }*/
 
     public boolean verifySignature(byte[] message, byte[] signature) {
-        //******* EDUARDO BEGIN **************//
-
-        return TOMUtil.verifySignature(manager.getStaticConf().getRSAPublicKey(clientId),
-                message, signature);
-
-        //******* EDUARDO END **************//
+        if(signatureVerificator != null) {
+            try {
+                return TOMUtil.verifySignature(signatureVerificator, message, signature);
+            } catch (SignatureException ex) {
+                ex.printStackTrace();
+            }
+        }
+        return false;
     }
 
     public void setLastMessageExecuted(int lastMessageExecuted) {

src/navigators/smart/clientsmanagement/ClientsManager.java

@@ -64,9 +64,13 @@ public class ClientsManager {
 
         if (clientData == null) {
             Logger.println("(ClientsManager.getClientData) Creating new client data, client id="+clientId);
-             //******* EDUARDO BEGIN **************//
-            clientData = new ClientData(clientId,manager);
-             //******* EDUARDO END **************//
+
+            //******* EDUARDO BEGIN **************//
+            clientData = new ClientData(clientId,
+                    (manager.getStaticConf().getUseSignatures() == 1)?
+                        manager.getStaticConf().getRSAPublicKey(clientId):
+                        null);
+            //******* EDUARDO END **************//
             clientsData.put(clientId, clientData);
         }
 

src/navigators/smart/tom/core/TOMLayer.java

@@ -63,7 +63,6 @@ import navigators.smart.tom.core.timer.messages.RTMessage;
 import navigators.smart.tom.util.BatchBuilder;
 import navigators.smart.tom.util.BatchReader;
 import navigators.smart.tom.util.Logger;
-import navigators.smart.tom.util.Storage;
 
 import navigators.smart.tom.util.TOMUtil;
 
@@ -356,7 +355,7 @@ public final class TOMLayer extends Thread implements RequestReceiver {
         // return the batch
         return bb.createBatch(System.currentTimeMillis(), numberOfNonces, numberOfMessages, totalMessageSize, 
                 this.reconfManager.getStaticConf().getUseSignatures() == 1, messages, signatures,this.reconfManager);
-        }
+    }
 
 
 
@@ -510,9 +509,8 @@ public final class TOMLayer extends Thread implements RequestReceiver {
      * @return
      */
     public TOMMessage[] checkProposedValue(byte[] proposedValue) {
-        if (Logger.debug) {
         Logger.println("(TOMLayer.isProposedValueValid) starting");
-        }
+
         BatchReader batchReader = new BatchReader(proposedValue, 
                 this.reconfManager.getStaticConf().getUseSignatures() == 1);
 

src/navigators/smart/tom/util/SignatureTest.java

+/*
+ * To change this template, choose Tools | Templates
+ * and open the template in the editor.
+ */
+
+package navigators.smart.tom.util;
+
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.PrivateKey;
+import java.security.PublicKey;
+import java.security.Signature;
+
+/**
+ *
+ * @author alysson
+ */
+public class SignatureTest {
+
+    public static void main(String[] args) throws Exception {
+        byte[] data = new byte[20];
+        byte[] signature;
+        Signature signEng;
+        long start, end;
+
+        KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA");
+        kpg.initialize(1024);
+        KeyPair kp = kpg.genKeyPair();
+        PublicKey publicKey = kp.getPublic();
+        PrivateKey privateKey = kp.getPrivate();
+
+        signEng = Signature.getInstance("SHA1withRSA");
+
+        for(int i=0; i<1000; i++) {
+            signEng = Signature.getInstance("SHA1withRSA");
+            signEng.initSign(privateKey);
+        }
+        start = System.currentTimeMillis();
+        for(int i=0; i<1000; i++) {
+            signEng = Signature.getInstance("SHA1withRSA");
+            signEng.initSign(privateKey);
+        }
+        end = System.currentTimeMillis();
+        System.out.println("1000 init sign: "+(end-start)+"ms");
+
+        for(int i=0; i<1000; i++) {
+            signEng.update(data);
+            signature = signEng.sign();
+        }
+        start = System.currentTimeMillis();
+        for(int i=0; i<1000; i++) {
+            signEng.update(data);
+            signature = signEng.sign();
+        }
+        end = System.currentTimeMillis();
+        System.out.println("1000 sign: "+(end-start)+"ms");
+
+        signEng.update(data);
+        signature = signEng.sign();
+
+        for(int i=0; i<1000; i++) {
+            signEng = Signature.getInstance("SHA1withRSA");
+            signEng.initVerify(publicKey);
+        }
+        start = System.currentTimeMillis();
+        for(int i=0; i<1000; i++) {
+            signEng = Signature.getInstance("SHA1withRSA");
+            signEng.initVerify(publicKey);
+        }
+        end = System.currentTimeMillis();
+        System.out.println("1000 init verify: "+(end-start)+"ms");
+
+        for(int i=0; i<1000; i++) {
+            signEng.update(data);
+            signEng.verify(signature);
+        }
+        start = System.currentTimeMillis();
+        for(int i=0; i<1000; i++) {
+            signEng.update(data);
+            signEng.verify(signature);
+        }
+        end = System.currentTimeMillis();
+        System.out.println("1000 verify: "+(end-start)+"ms");
+    }
+
+}

src/navigators/smart/tom/util/TOMUtil.java

@@ -25,7 +25,9 @@ import java.io.ObjectOutputStream;
 import java.security.PrivateKey;
 import java.security.PublicKey;
 import java.security.Signature;
+import java.security.SignatureException;
 import java.util.Arrays;
+import java.util.concurrent.Semaphore;
 import java.util.concurrent.locks.ReentrantLock;
 import navigators.smart.reconfiguration.ViewManager;
 
@@ -80,13 +82,16 @@ public class TOMUtil {
 
         } catch (IOException ex) {
             ex.printStackTrace();
+            return null;
         }
 
         return bOut.toByteArray();
     }
 
     public static Object getObject(byte[] b) {
-        if (b == null) System.out.println("O ARRAY E NULL!!!!");
+        if (b == null)
+            return null;
+
         ByteArrayInputStream bInp = new ByteArrayInputStream(b);
         try {
             ObjectInputStream obInp = new ObjectInputStream(bInp);
@@ -95,7 +100,6 @@ public class TOMUtil {
             bInp.close();
             return ret;
         } catch (Exception ex) {
-            System.out.println("Isto rebenta aqui!!");
             ex.printStackTrace();
             return null;
         }
@@ -111,6 +115,7 @@ public class TOMUtil {
      */
     public static byte[] signMessage(PrivateKey key, byte[] message) {
         lock.lock();
+        byte[] result = null;
         try {
             if (signatureEngine == null) {
                 signatureEngine = Signature.getInstance("SHA1withRSA");
@@ -120,14 +125,13 @@ public class TOMUtil {
 
             signatureEngine.update(message);
 
-            byte[] result = signatureEngine.sign();
-            lock.unlock();
-            return result;
+            result = signatureEngine.sign();
         } catch (Exception e) {
-            lock.unlock();
             e.printStackTrace();
-            return null;
         }
+
+        lock.unlock();
+        return result;
     }
 
     /**
@@ -136,10 +140,11 @@ public class TOMUtil {
      * @param key the public key to be used to verify the signature
      * @param message the signed message
      * @param signature the signature to be verified
-     * @return the signature
+     * @return true if the signature is valid, false otherwise
      */
     public static boolean verifySignature(PublicKey key, byte[] message, byte[] signature) {
         lock.lock();
+        boolean result = false;
         //long startTime = System.nanoTime();
         try {
             if (signatureEngine == null) {
@@ -148,9 +153,7 @@ public class TOMUtil {
 
             signatureEngine.initVerify(key);
 
-            signatureEngine.update(message);
-
-            boolean result = signatureEngine.verify(signature);
+            result = verifySignature(signatureEngine, message, signature);
             /*
             st.store(System.nanoTime()-startTime);
             //statistics about signature execution time
@@ -166,14 +169,30 @@ public class TOMUtil {
             count = 0;
             st = new Storage(BENCHMARK_PERIOD);
             }
-             */
-            lock.unlock();
-            return result;
+         */
         } catch (Exception e) {
-            lock.unlock();
             e.printStackTrace();
-            return false;
         }
+
+        lock.unlock();
+        return result;
+    }
+
+    /**
+     * Verify the signature of a message.
+     *
+     * @param initializedSignatureEngine a signature engine already initialized
+     *        for verification
+     * @param message the signed message
+     * @param signature the signature to be verified
+     * @return true if the signature is valid, false otherwise
+     */
+    public static boolean verifySignature(Signature initializedSignatureEngine, byte[] message, byte[] signature) throws SignatureException {
+        //TODO: limit the amount of parallelization we can do to save some cores for other tasks
+        //maybe we can use a semaphore here initialized with the maximum number of parallel verifications:
+        //Semaphore sem = new Semaphore(10, true); then we can run sem.acquire() and sem.release()
+        initializedSignatureEngine.update(message);
+        return initializedSignatureEngine.verify(signature);
     }
 
     public static String byteArrayToString(byte[] b) {