From 7da9e64c27cda4147a6262ff8846e923c9979496 Mon Sep 17 00:00:00 2001
From: Daniel <dhaavi@users.noreply.github.com>
Date: Wed, 8 Apr 2020 14:07:59 +0200
Subject: [PATCH] Save blocked DNS queries

---
 nameserver/nameserver.go | 9 ++++++---
 network/connection.go    | 7 +++----
 network/dns.go           | 5 +++--
 3 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/nameserver/nameserver.go b/nameserver/nameserver.go
index c2ee2ef3..f4b10fa7 100644
--- a/nameserver/nameserver.go
+++ b/nameserver/nameserver.go
@@ -195,11 +195,11 @@ func handleRequest(ctx context.Context, w dns.ResponseWriter, query *dns.Msg) er
 	case network.VerdictBlock:
 		tracer.Infof("nameserver: %s blocked, returning nxdomain", conn)
 		returnNXDomain(w, query)
-		// FIXME: save denied dns connection
+		conn.Save() // save blocked request
 		return nil
 	case network.VerdictDrop:
 		tracer.Infof("nameserver: %s dropped, not replying", conn)
-		// FIXME: save denied dns connection
+		conn.Save() // save dropped request
 		return nil
 	}
 
@@ -218,7 +218,7 @@ func handleRequest(ctx context.Context, w dns.ResponseWriter, query *dns.Msg) er
 	if rrCache == nil {
 		tracer.Infof("nameserver: %s implicitly denied by filtering the dns response, returning nxdomain", conn)
 		returnNXDomain(w, query)
-		// FIXME: save denied dns connection
+		conn.Save() // save blocked request
 		return nil
 	}
 
@@ -265,5 +265,8 @@ func handleRequest(ctx context.Context, w dns.ResponseWriter, query *dns.Msg) er
 	_ = w.WriteMsg(m)
 	tracer.Debugf("nameserver: returning response %s%s to %s", q.FQDN, q.QType, conn.Process())
 
+	// save dns request as open
+	network.SaveOpenDNSRequest(conn)
+
 	return nil
 }
diff --git a/network/connection.go b/network/connection.go
index 1577d5c8..5a0626c3 100644
--- a/network/connection.go
+++ b/network/connection.go
@@ -71,7 +71,6 @@ func NewConnectionFromDNSRequest(ctx context.Context, fqdn string, ip net.IP, po
 		Started: timestamp,
 		Ended:   timestamp,
 	}
-	saveOpenDNSRequest(dnsConn)
 	return dnsConn
 }
 
@@ -218,8 +217,8 @@ func (conn *Connection) SaveWhenFinished() {
 	conn.saveWhenFinished = true
 }
 
-// save saves the link object in the storage and propagates the change.
-func (conn *Connection) save() {
+// Save saves the connection in the storage and propagates the change through the database system.
+func (conn *Connection) Save() {
 	if conn.ID == "" {
 
 		// dns request
@@ -336,7 +335,7 @@ func (conn *Connection) packetHandler() {
 		// must not be locked, will deadlock with cleaner functions
 		if conn.saveWhenFinished {
 			conn.saveWhenFinished = false
-			conn.save()
+			conn.Save()
 		}
 		// submit trace logs
 		log.Tracer(pkt.Ctx()).Submit()
diff --git a/network/dns.go b/network/dns.go
index 2b0f2301..88ca7be3 100644
--- a/network/dns.go
+++ b/network/dns.go
@@ -26,7 +26,8 @@ func removeOpenDNSRequest(pid int, fqdn string) {
 	delete(openDNSRequests, key)
 }
 
-func saveOpenDNSRequest(conn *Connection) {
+// SaveOpenDNSRequest saves a dns request connection that was allowed to proceed.
+func SaveOpenDNSRequest(conn *Connection) {
 	openDNSRequestsLock.Lock()
 	defer openDNSRequestsLock.Unlock()
 
@@ -65,7 +66,7 @@ func writeOpenDNSRequestsToDB() {
 	for id, conn := range openDNSRequests {
 		conn.Lock()
 		if conn.Ended < threshold {
-			conn.save()
+			conn.Save()
 			delete(openDNSRequests, id)
 		}
 		conn.Unlock()