Merge pull request #274 from cconlon/WolfSSLAuthStoreLock

Reduce synchronization overhead in WolfSSLAuthStore

src/java/com/wolfssl/WolfSSLDebug.java

@@ -548,9 +548,13 @@ public class WolfSSLDebug {
     }
 
     /**
-     * Check if debug logging is enabled for the specified component
+     * Check if debug logging is enabled for the specified component.
+     *
+     * @param component the component to check (JNI or JSSE)
+     *
+     * @return true if debug logging is enabled for the component,
      */
-    private static boolean isDebugEnabled(Component component) {
+    public static boolean isDebugEnabled(Component component) {
         if (component == Component.JSSE && DEBUG) {
             return true;
         }

src/java/com/wolfssl/provider/jsse/WolfSSLAuthStore.java

@@ -314,13 +314,14 @@ public class WolfSSLAuthStore {
      *         object if not in cache, called on server side, or host
      *         is null
      */
-    protected synchronized WolfSSLImplementSSLSession getSession(
+    protected WolfSSLImplementSSLSession getSession(
         WolfSSLSession ssl, int port, String host, boolean clientMode,
         String[] enabledCipherSuites, String[] enabledProtocols) {
 
         boolean needNewSession = false;
         WolfSSLImplementSSLSession ses = null;
         String toHash = null;
+        int hashCode = 0;
 
         if (ssl == null) {
             return null;
@@ -339,22 +340,25 @@ public class WolfSSLAuthStore {
          * Synchronizes on storeLock internally. */
         printSessionStoreStatus();
 
-        /* Lock on static/global storeLock, since Java session cache table
+        /* Generate cache key hash (host:port), outside lock */
-         * is shared between all threads */
+        toHash = host.concat(Integer.toString(port));
+        hashCode = toHash.hashCode();
+
+        /* Lock on static/global storeLock while getting session out of
+         * store, since Java session cache table is shared between all
+         * threads */
         synchronized (storeLock) {
 
-            /* Generate cache key hash (host:port) */
-            toHash = host.concat(Integer.toString(port));
-
             /* Try getting session out of Java store */
-            ses = store.get(toHash.hashCode());
+            ses = store.get(hashCode);
 
             /* Remove old entry from table. TLS 1.3 binder changes between
              * resumptions and stored session should only be used to
              * resume once. New session structure/object will be cached
              * after the resumed session completes the handshake, for
              * subsequent resumption attempts to use. */
-            store.remove(toHash.hashCode());
+            store.remove(hashCode);
+        }
 
         /* Check conditions where we need to create a new new session:
          *   1. Session not found in cache
@@ -437,7 +441,6 @@ public class WolfSSLAuthStore {
 
         return ses;
     }
-    }
 
     /**
      * Check if cipher suite from original WOLFSSL_SESSION
@@ -531,6 +534,11 @@ public class WolfSSLAuthStore {
      * prints out host:port of all sessions stored in the store.
      * Called by getSession(). */
     private void printSessionStoreStatus() {
+
+        if (!WolfSSLDebug.isDebugEnabled(WolfSSLDebug.Component.JSSE)) {
+            return;
+        }
+
         synchronized (storeLock) {
             Collection<WolfSSLImplementSSLSession> values =
                 store.values();
@@ -640,8 +648,6 @@ public class WolfSSLAuthStore {
             return WolfSSL.SSL_FAILURE;
         }
 
-        /* Lock access to store while adding new session, store is global */
-        synchronized (storeLock) {
         if (session.getPeerHost() != null) {
             /* Generate key for storing into session table (host:port) */
             toHash = session.getPeerHost().concat(Integer.toString(
@@ -669,10 +675,14 @@ public class WolfSSLAuthStore {
                 session.getPeerHost() + ", port: " +
                 session.getPeerPort() + ") " + "hashCode = " + hashCode +
                 " side = " + session.getSideString());
-                store.put(hashCode, session);
             session.isInTable = true;
-                printSessionStoreStatus();
+
+            /* Lock access to store while adding new session, store is global */
+            synchronized (storeLock) {
+                store.put(hashCode, session);
             }
+
+            printSessionStoreStatus();
         }
 
         return WolfSSL.SSL_SUCCESS;