From 3750040174e5b1749a356382935bae2b113868fb Mon Sep 17 00:00:00 2001
From: nullswan <pro@nullswan.io>
Date: Sun, 22 Sep 2024 13:27:02 +0200
Subject: [PATCH] feat(internal/bpf): enhance NetworkEvent with enums for
 direction and protocol

---
 internal/bpf/event.go           | 32 ++++++++++++++++++++++++++++++--
 internal/bpf/event_processor.go |  4 +++-
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/internal/bpf/event.go b/internal/bpf/event.go
index d50c20b..525552d 100644
--- a/internal/bpf/event.go
+++ b/internal/bpf/event.go
@@ -27,6 +27,34 @@ type NetworkEvent struct {
 	Sport uint16
 	Dport uint16
 
-	Direction uint8
-	Protocol  uint8
+	Direction NetworkEventDirection
+	Protocol  NetworkEventProtocol
+}
+
+type NetworkEventDirection uint8
+
+const (
+	NetworkEventDirectionInbound  NetworkEventDirection = 0
+	NetworkEventDirectionOutbound NetworkEventDirection = 1
+)
+
+func (d NetworkEventDirection) String() string {
+	if d == NetworkEventDirectionInbound {
+		return "inbound"
+	}
+	return "outbound"
+}
+
+type NetworkEventProtocol uint8
+
+const (
+	NetworkEventProtocolTCP NetworkEventProtocol = 6
+	NetworkEventProtocolUDP NetworkEventProtocol = 17
+)
+
+func (p NetworkEventProtocol) String() string {
+	if p == NetworkEventProtocolTCP {
+		return "tcp"
+	}
+	return "udp"
 }
diff --git a/internal/bpf/event_processor.go b/internal/bpf/event_processor.go
index 7a5635b..8d67b50 100644
--- a/internal/bpf/event_processor.go
+++ b/internal/bpf/event_processor.go
@@ -35,7 +35,9 @@ func ProcessNetworkEvent(
 			Debug("Received network event")
 	}
 
-	if event.Protocol == 17 && event.Direction == 1 && event.Dport == 53 {
+	if event.Protocol == NetworkEventProtocolUDP &&
+		event.Direction == NetworkEventDirectionOutbound &&
+		event.Dport == 53 {
 		metrics.DNSQueryCounter.WithLabelValues(container).Inc()
 	}