refactored message handling

src/libcharon/plugins/tnccs_20/tnccs_20.c

@@ -116,14 +116,8 @@ METHOD(tnccs_t, send_message, void,
 	this->mutex->unlock(this->mutex);
 }
 
-static status_t handle_messages(private_tnccs_20_t *this, pb_tnc_batch_t *batch)
+static void handle_message(private_tnccs_20_t *this, pb_tnc_message_t *msg)
 {
-	enumerator_t *enumerator;
-	pb_tnc_message_t *msg;
-
-	enumerator = batch->create_msg_enumerator(batch);
-	while (enumerator->enumerate(enumerator, &msg))
-	{
 	switch (msg->get_type(msg))
 	{
 		case PB_MSG_EXPERIMENTAL:
@@ -239,8 +233,7 @@ static status_t handle_messages(private_tnccs_20_t *this, pb_tnc_batch_t *batch)
 			lang_msg = (pb_language_preference_message_t*)msg;
 			lang = lang_msg->get_language_preference(lang_msg);
 
-				DBG2(DBG_TNC, "setting language preference '%.*s'",
-							   lang.len, lang.ptr);
+			DBG2(DBG_TNC, "setting language preference '%.*s'", lang.len, lang.ptr);
 			this->recs->set_preferred_language(this->recs, lang);
 			break;
 		}
@@ -261,10 +254,6 @@ static status_t handle_messages(private_tnccs_20_t *this, pb_tnc_batch_t *batch)
 		default:
 			break;
 	}
-	}
-	enumerator->destroy(enumerator);
-
-	return SUCCESS;
 }
 
 METHOD(tls_t, process, status_t,
@@ -296,10 +285,50 @@ METHOD(tls_t, process, status_t,
 	batch = pb_tnc_batch_create_from_data(this->is_server, data);
 	status = batch->process(batch, this->state_machine);
 
-	switch (status)
+	if (status != FAILED)
 	{
-		case SUCCESS:
-			handle_messages(this, batch);
+		enumerator_t *enumerator;
+		pb_tnc_message_t *msg;
+		pb_tnc_batch_type_t batch_type;
+		bool empty = TRUE;
+
+		batch_type = batch->get_type(batch);
+
+		if (batch_type == PB_BATCH_CRETRY)
+		{
+			this->mutex->lock(this->mutex);
+			if (this->batch)
+			{
+				DBG1(DBG_TNC, "cancelling PB-TNC %N Batch",
+					pb_tnc_batch_type_names, this->batch->get_type(this->batch));
+				this->batch->destroy(this->batch);
+			 }
+			this->batch = pb_tnc_batch_create(this->is_server, PB_BATCH_SRETRY);
+			this->mutex->unlock(this->mutex);
+		}
+		else if (batch_type == PB_BATCH_SRETRY)
+		{
+			/* Restart the measurements */
+			charon->imcs->notify_connection_change(charon->imcs,
+			this->connection_id, TNC_CONNECTION_STATE_HANDSHAKE);
+			charon->imcs->begin_handshake(charon->imcs, this->connection_id);
+		}
+
+		enumerator = batch->create_msg_enumerator(batch);
+		while (enumerator->enumerate(enumerator, &msg))
+		{
+			handle_message(this, msg);
+			empty = FALSE;
+		}
+		enumerator->destroy(enumerator);
+
+		/* received an empty CLOSE Batch from PB-TNC Client */
+		if (this->is_server && batch_type == PB_BATCH_CLOSE && empty)
+		{
+			batch->destroy(batch);
+			return SUCCESS;
+		}
+
 		if (this->is_server)
 		{
 			charon->imvs->batch_ending(charon->imvs, this->connection_id);
@@ -308,7 +337,10 @@ METHOD(tls_t, process, status_t,
 		{
 			charon->imcs->batch_ending(charon->imcs, this->connection_id);
 		}
-			break;
+	}
+
+	switch (status)
+	{
 		case FAILED:
 			this->mutex->lock(this->mutex);
 			if (this->batch)
@@ -319,7 +351,7 @@ METHOD(tls_t, process, status_t,
 			 }
 			this->batch = pb_tnc_batch_create(this->is_server, PB_BATCH_CLOSE);
 			this->mutex->unlock(this->mutex);
-			/* fall through */
+			/* fall through to add error messages to outbound batch */
 		case VERIFY_ERROR:
 			enumerator = batch->create_error_enumerator(batch);
 			while (enumerator->enumerate(enumerator, &msg))
@@ -329,6 +361,8 @@ METHOD(tls_t, process, status_t,
 				this->mutex->unlock(this->mutex);
 			}
 			enumerator->destroy(enumerator);
+			break;
+		case SUCCESS:
 		default:
 			break;
 	}
@@ -340,6 +374,8 @@ METHOD(tls_t, process, status_t,
 METHOD(tls_t, build, status_t,
 	private_tnccs_20_t *this, void *buf, size_t *buflen, size_t *msglen)
 {
+	status_t status;
+
 	if (!this->is_server && !this->connection_id)
 	{
 		pb_tnc_message_t *msg;
@@ -369,13 +405,24 @@ METHOD(tls_t, build, status_t,
 		charon->imcs->begin_handshake(charon->imcs, this->connection_id);
 	}
 
+	/* Do not allow any asynchronous IMCs or IMVs to add additional messages */
+	this->mutex->lock(this->mutex);
+
+	/**
+	 * if the DECIDED state has been reached, close down the TNCCS connection
+	 * by sending an empty CLOSE batch unless a CRETRY batch is under way
+	 */
+	if (this->state_machine->get_state(this->state_machine) == PB_STATE_DECIDED &&
+	   !this->batch)
+	{
+		this->batch = pb_tnc_batch_create(this->is_server, PB_BATCH_CLOSE);
+	}
+
 	if (this->batch)
 	{
 		pb_tnc_batch_type_t batch_type;
-		status_t status;
 		chunk_t data;
 
-		this->mutex->lock(this->mutex);
 		batch_type = this->batch->get_type(this->batch);
 
 		if (this->state_machine->send_batch(this->state_machine, batch_type))
@@ -401,15 +448,15 @@ METHOD(tls_t, build, status_t,
 
 		this->batch->destroy(this->batch);
 		this->batch = NULL;
-		this->mutex->unlock(this->mutex);
-
-		return status;
 	}
 	else
 	{
 		DBG1(DBG_TNC, "no TNCCS Batch to send");
-		return INVALID_STATE;
+		status = INVALID_STATE;
 	}
+	this->mutex->unlock(this->mutex);
+
+	return status;
 }
 
 METHOD(tls_t, is_server, bool,