Use job priorities in process_message job based on exchange types

src/libcharon/processing/jobs/process_message_job.c

@@ -87,7 +87,22 @@ METHOD(job_t, execute, void,
 METHOD(job_t, get_priority, job_priority_t,
 	private_process_message_job_t *this)
 {
-	return JOB_PRIO_MEDIUM;
+	switch (this->message->get_exchange_type(this->message))
+	{
+		case IKE_AUTH:
+			/* IKE auth is rather expensive and often blocking, low priority */
+			return JOB_PRIO_LOW;
+		case INFORMATIONAL:
+			/* INFORMATIONALs are inexpensive, for DPD we should have low
+			 * reaction times */
+			return JOB_PRIO_HIGH;
+		case IKE_SA_INIT:
+		case CREATE_CHILD_SA:
+		default:
+			/* IKE_SA_INIT is expensive, but we will drop them in the receiver
+			 * if we are overloaded */
+			return JOB_PRIO_MEDIUM;
+	}
 }
 
 /*