From 97488efed7a6e9d294895989cbf557603b0b433f Mon Sep 17 00:00:00 2001
From: Matt Joiner <anacrolix@gmail.com>
Date: Mon, 22 May 2023 15:27:06 +1000
Subject: [PATCH] Add holepunch message fuzzing

---
 .../ut-holepunch/ut-holepunch_test.go         | 63 +++++++++++++++++++
 1 file changed, 63 insertions(+)
 create mode 100644 peer_protocol/ut-holepunch/ut-holepunch_test.go

diff --git a/peer_protocol/ut-holepunch/ut-holepunch_test.go b/peer_protocol/ut-holepunch/ut-holepunch_test.go
new file mode 100644
index 00000000..7221e1f7
--- /dev/null
+++ b/peer_protocol/ut-holepunch/ut-holepunch_test.go
@@ -0,0 +1,63 @@
+package utHolepunch
+
+import (
+	"bytes"
+	"net/netip"
+	"testing"
+
+	qt "github.com/frankban/quicktest"
+)
+
+var exampleMsgs = []Msg{
+	{
+		MsgType:  Rendezvous,
+		AddrPort: netip.MustParseAddrPort("[1234::1]:42069"),
+		ErrCode:  16777216,
+	},
+	{
+		MsgType:  Connect,
+		AddrPort: netip.MustParseAddrPort("1.2.3.4:42069"),
+		ErrCode:  16777216,
+	},
+}
+
+func TestUnmarshalMsg(t *testing.T) {
+	c := qt.New(t)
+	for _, m := range exampleMsgs {
+		b, err := m.MarshalBinary()
+		c.Assert(err, qt.IsNil)
+		expectedLen := 24
+		if m.AddrPort.Addr().Is4() {
+			expectedLen = 12
+		}
+		c.Check(b, qt.HasLen, expectedLen)
+		var um Msg
+		err = um.UnmarshalBinary(b)
+		c.Assert(err, qt.IsNil)
+		c.Check(um, qt.Equals, m)
+	}
+}
+
+func FuzzMsg(f *testing.F) {
+	for _, m := range exampleMsgs {
+		emb, err := m.MarshalBinary()
+		if err != nil {
+			f.Fatal(err)
+		}
+		f.Add(emb)
+	}
+	f.Fuzz(func(t *testing.T, b []byte) {
+		var m Msg
+		err := m.UnmarshalBinary(b)
+		if err != nil {
+			t.SkipNow()
+		}
+		mb, err := m.MarshalBinary()
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !bytes.Equal(b, mb) {
+			t.FailNow()
+		}
+	})
+}
-- 
2.48.1