Add tracked vpnruntime implementation for CI guard tests

agents/rap-node-agent/internal/vpnruntime/checksum_test.go

@@ -0,0 +1,52 @@
+package vpnruntime
+
+import (
+	"encoding/binary"
+	"testing"
+)
+
+func TestNormalizeIPv4PacketChecksumsRepairsTCP(t *testing.T) {
+	packet := []byte{
+		0x45, 0x00, 0x00, 0x28, 0x00, 0x00, 0x40, 0x00, 0x40, 0x06, 0x12, 0x34, 192, 168, 200, 61, 10, 77, 0, 2,
+		0x46, 0xa0, 0xdd, 0x78, 0, 0, 0, 1, 0, 0, 0, 0, 0x50, 0x12, 0x72, 0x10, 0xab, 0xcd, 0, 0,
+	}
+	if !normalizeIPv4PacketChecksums(packet) {
+		t.Fatal("normalize returned false")
+	}
+	if got := checksum(packet[:20]); got != 0 {
+		t.Fatalf("ip checksum verification = %#x, want 0", got)
+	}
+	tcp := packet[20:]
+	pseudo := make([]byte, 12+len(tcp))
+	copy(pseudo[0:4], packet[12:16])
+	copy(pseudo[4:8], packet[16:20])
+	pseudo[9] = 6
+	binary.BigEndian.PutUint16(pseudo[10:12], uint16(len(tcp)))
+	copy(pseudo[12:], tcp)
+	if got := checksum(pseudo); got != 0 {
+		t.Fatalf("tcp checksum verification = %#x, want 0", got)
+	}
+}
+
+func TestNormalizeIPv4PacketChecksumsRepairsUDP(t *testing.T) {
+	packet := []byte{
+		0x45, 0x00, 0x00, 0x20, 0, 0, 0x40, 0, 0x40, 0x11, 0x12, 0x34, 10, 77, 0, 2, 192, 168, 200, 210,
+		0x30, 0x39, 0x00, 0x35, 0x00, 0x0c, 0xab, 0xcd, 0xde, 0xad, 0xbe, 0xef,
+	}
+	if !normalizeIPv4PacketChecksums(packet) {
+		t.Fatal("normalize returned false")
+	}
+	if got := checksum(packet[:20]); got != 0 {
+		t.Fatalf("ip checksum verification = %#x, want 0", got)
+	}
+	udp := packet[20:]
+	pseudo := make([]byte, 12+len(udp))
+	copy(pseudo[0:4], packet[12:16])
+	copy(pseudo[4:8], packet[16:20])
+	pseudo[9] = 17
+	binary.BigEndian.PutUint16(pseudo[10:12], uint16(len(udp)))
+	copy(pseudo[12:], udp)
+	if got := checksum(pseudo); got != 0 {
+		t.Fatalf("udp checksum verification = %#x, want 0", got)
+	}
+}