Add holepunch message fuzzing

diff --git a/peer_protocol/ut-holepunch/ut-holepunch_test.go b/peer_protocol/ut-holepunch/ut-holepunch_test.go
new file mode 100644 (file)
index 0000000..7221e1f
--- /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()
+               }
+       })
+}