nearly completed PA-TNC error handling

src/libimcv/imv/imv_agent.c

@@ -319,6 +319,63 @@ METHOD(imv_agent_t, set_recommendation, TNC_Result,
 	return this->provide_recommendation(this->id, connection_id, rec, eval);
 }
 
+METHOD(imv_agent_t, receive_message, TNC_Result,
+	private_imv_agent_t *this, TNC_ConnectionID connection_id, chunk_t msg,
+	TNC_MessageType msg_type, pa_tnc_msg_t **pa_tnc_msg)
+{
+	pa_tnc_msg_t *pa_msg, *error_msg;
+	pa_tnc_attr_t *error_attr;
+	enumerator_t *enumerator;
+	TNC_Result result;
+
+	DBG2(DBG_IMV, "IMV %u \"%s\" received message type 0x%08x for Connection ID %u",
+				   this->id, this->name, msg_type, connection_id);
+
+	*pa_tnc_msg = NULL;
+	pa_msg = pa_tnc_msg_create_from_data(msg);
+
+	switch (pa_msg->process(pa_msg))
+	{
+		case SUCCESS:
+			*pa_tnc_msg = pa_msg;
+			break;
+		case VERIFY_ERROR:
+			if (!this->send_message)
+			{
+				/* TNCS doen't have a SendMessage() function */
+				return TNC_RESULT_FATAL;
+			}
+
+			/* build error message */
+			error_msg = pa_tnc_msg_create();
+			enumerator = pa_msg->create_error_enumerator(pa_msg);
+			while (enumerator->enumerate(enumerator, &error_attr))
+			{
+				error_msg->add_attribute(error_msg,
+										 error_attr->get_ref(error_attr));
+			}
+			enumerator->destroy(enumerator);
+			error_msg->build(error_msg);
+
+			/* send error message */
+			msg = error_msg->get_encoding(error_msg);
+			result = this->send_message(this->id, connection_id,
+										msg.ptr, msg.len, msg_type);
+
+			/* clean up */
+			error_msg->destroy(error_msg);
+			pa_msg->destroy(pa_msg);
+			return result;
+		case FAILED:
+		default:
+			pa_msg->destroy(pa_msg);
+			return set_recommendation(this, connection_id,
+							TNC_IMV_ACTION_RECOMMENDATION_NO_RECOMMENDATION,
+							TNC_IMV_EVALUATION_RESULT_ERROR);
+	}
+	return TNC_RESULT_SUCCESS;
+}
+
 METHOD(imv_agent_t, provide_recommendation, TNC_Result,
 	private_imv_agent_t *this, TNC_ConnectionID connection_id)
 {
@@ -373,6 +430,7 @@ imv_agent_t *imv_agent_create(const char *name,
 			.change_state = _change_state,
 			.get_state = _get_state,
 			.send_message = _send_message,
+			.receive_message = _receive_message,
 			.set_recommendation = _set_recommendation,
 			.provide_recommendation = _provide_recommendation,
 			.destroy = _destroy,

src/libimcv/imv/imv_agent.h

@@ -22,6 +22,7 @@
 #define IMV_AGENT_H_
 
 #include "imv_state.h"
+#include "pa_tnc/pa_tnc_msg.h"
 
 #include <tncifimv.h>
 #include <pen/pen.h>
@@ -131,7 +132,7 @@ struct imv_agent_t {
 					  TNC_ConnectionID connection_id, imv_state_t **state);
 
 	/**
-	 * Call when an IMV-IMC message is to be sent
+	 * Call when a PA-TNC message is to be sent
 	 *
 	 * @param connection_id		network connection ID assigned by TNCS
 	 * @param msg				message to send
@@ -140,6 +141,20 @@ struct imv_agent_t {
 	TNC_Result (*send_message)(imv_agent_t *this,
 							   TNC_ConnectionID connection_id, chunk_t msg);
 
+	/**
+	 * Call when a PA-TNC message was received
+	 *
+	 * @param connection_id		network connection ID assigned by TNCS
+	 * @param msg				received unparsed message
+	 * @param msg_type			message type of the received message
+	 * @param pa_tnc_message	parsed PA-TNC message or NULL if an error occurred
+	 * @return					TNC result code
+	 */
+	TNC_Result (*receive_message)(imv_agent_t *this,
+								  TNC_ConnectionID connection_id, chunk_t msg,
+								  TNC_MessageType msg_type,
+								  pa_tnc_msg_t **pa_tnc_msg);
+
 	/**
 	 * Set Action Recommendation and Evaluation Result in the IMV state
 	 *