[fix] SSL session resumption failure due to BC classloader mismatch (#369)

Author: thiagoparrilha

src/main/java/org/jruby/ext/openssl/BCSSLSupport.java

@@ -46,8 +46,16 @@ static SSLSession getBCSession(final SSLEngine engine) {
 
     static boolean setBCSessionToResume(final SSLEngine engine, final SSLSession session) {
         if (engine instanceof BCSSLEngine && session instanceof BCExtendedSSLSession) {
-            ((BCSSLEngine) engine).setBCSessionToResume((BCExtendedSSLSession) session);
-            return true;
+            try {
+                ((BCSSLEngine) engine).setBCSessionToResume((BCExtendedSSLSession) session);
+                return true;
+            } catch (IllegalArgumentException e) {
+                // This can happen when a Java gem's post-install hook (e.g. fast-rsa-engine)
+                // downloads BC JARs via Maven and loads them under a new classloader. At that
+                // point there are two copies of BC in the JVM, and ProvSSLEngine rejects the
+                // stored session because it came from a different classloader context.
+                // Just fall through and let the caller do a fresh handshake.
+            }
         }
         return false;
     }

src/main/java/org/jruby/ext/openssl/SSLSocket.java

@@ -1356,10 +1356,12 @@ private void tryResumeSessionIfSet(final ThreadContext context) {
 
         if (BCSSLSupport.setBCSessionToResume(engine, setSession.sslSession())) return;
 
-        // can not support this without the (BC) SSL provider internals (e.g. on SunJSSE)
-        // but we can assume setting a session= is meant to be a *forced* session re-use:
+        // Without BC internals (e.g. on SunJSSE) we can't force session re-use.
+        // We used to call setEnableSessionCreation(false) here to signal that intent,
+        // but that backfires: if the stored session can't be resumed for any reason
+        // (including the BC classloader mismatch above), BC-JSSE throws instead of
+        // falling back to a fresh handshake. Leave session creation enabled.
         if (reusableSSLEngine()) {
-            engine.setEnableSessionCreation(false);
             final SSLSession session = getSession(context.runtime);
             if (!setSession.equals(session)) {
                 session.set_timeout(context, setSession.timeout(context));