input+lnwallet: move some MuSig2 calls to input pkg

As a preparation for making it possible to version switch calls to the MuSig2 API, we move some of the calls to the input package where in a future commit we'll call the corresponding code in the correct package.
2025-08-29 15:11:09 +02:00 · 2023-01-27 16:13:13 +01:00
parent 4f5ede84c6
commit 13789f5d95
4 changed files with 217 additions and 43 deletions
--- a/input/musig2_test.go
+++ b/input/musig2_test.go
@@ -0,0 +1,122 @@
+package input
+
+import (
+	"encoding/hex"
+	"testing"
+
+	"github.com/btcsuite/btcd/btcec/v2"
+	"github.com/btcsuite/btcd/btcec/v2/schnorr"
+	"github.com/stretchr/testify/require"
+)
+
+var (
+	hexDecode = func(keyStr string) []byte {
+		keyBytes, _ := hex.DecodeString(keyStr)
+		return keyBytes
+	}
+	dummyPubKey1, _ = btcec.ParsePubKey(hexDecode(
+		"02ec95e4e8ad994861b95fc5986eedaac24739e5ea3d0634db4c8ccd44cd" +
+			"a126ea",
+	))
+	dummyPubKey2, _ = btcec.ParsePubKey(hexDecode(
+		"0356167ba3e54ac542e86e906d4186aba9ca0b9df45001c62b753d33fe06" +
+			"f5b4e8",
+	))
+	dummyPubKey3, _ = btcec.ParsePubKey(hexDecode(
+		"02a9b0e1777e35d4620061a9fb0e614bf0254a50dea4f872babf6d44bf4d" +
+			"8ee7c6",
+	))
+
+	testVector040Key1, _ = schnorr.ParsePubKey(hexDecode(
+		"F9308A019258C31049344F85F89D5229B531C845836F99B08601F113BCE0" +
+			"36F9",
+	))
+	testVector040Key2, _ = schnorr.ParsePubKey(hexDecode(
+		"DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502B" +
+			"A659",
+	))
+	testVector040Key3, _ = schnorr.ParsePubKey(hexDecode(
+		"3590A94E768F8E1815C2F24B4D80A8E3149316C3518CE7B7AD338368D038" +
+			"CA66",
+	))
+
+	bip86Tweak = &MuSig2Tweaks{TaprootBIP0086Tweak: true}
+)
+
+func TestMuSig2CombineKeys(t *testing.T) {
+	t.Parallel()
+
+	testCases := []struct {
+		name                string
+		keys                []*btcec.PublicKey
+		tweak               *MuSig2Tweaks
+		expectedErr         string
+		expectedFinalKey    string
+		expectedPreTweakKey string
+	}{{
+		name:  "v0.4.0 two dummy keys BIP86",
+		keys:  []*btcec.PublicKey{dummyPubKey1, dummyPubKey2},
+		tweak: bip86Tweak,
+		expectedFinalKey: "03b54fb320a8fc3589e86a1559c6aaa774fbab4e4d" +
+			"9fbf31e2fd836b661ac6a132",
+		expectedPreTweakKey: "0279c76a15dcf6786058a571e4022b78633e1bf" +
+			"8a7a4ca440bcbbeeaea772228a2",
+	}, {
+		name: "v0.4.0 three dummy keys BIP86",
+		keys: []*btcec.PublicKey{
+			dummyPubKey1, dummyPubKey2, dummyPubKey3,
+		},
+		tweak: bip86Tweak,
+		expectedFinalKey: "03fa8195d584b195476f20e2fe978fd7312f4b08f2" +
+			"777f080bcdfc9350603cd6e7",
+		expectedPreTweakKey: "03e615b8aad4ed10544537bc48b1d6600e15773" +
+			"476a675c6cbba6808f21b1988e5",
+	}, {
+		name: "v0.4.0 three test vector keys BIP86",
+		keys: []*btcec.PublicKey{
+			testVector040Key1, testVector040Key2, testVector040Key3,
+		},
+		tweak: bip86Tweak,
+		expectedFinalKey: "025b257b4e785d61157ef5303051f45184bd5cb47b" +
+			"c4b4069ed4dd4536459cb83b",
+		expectedPreTweakKey: "02d70cd69a2647f7390973df48cbfa2ccc407b8" +
+			"b2d60b08c5f1641185c7998a290",
+	}, {
+		name: "v0.4.0 three test vector keys BIP86 reverse order",
+		keys: []*btcec.PublicKey{
+			testVector040Key3, testVector040Key2, testVector040Key1,
+		},
+		tweak: bip86Tweak,
+		expectedFinalKey: "025b257b4e785d61157ef5303051f45184bd5cb47b" +
+			"c4b4069ed4dd4536459cb83b",
+		expectedPreTweakKey: "02d70cd69a2647f7390973df48cbfa2ccc407b8" +
+			"b2d60b08c5f1641185c7998a290",
+	}}
+
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.name, func(tt *testing.T) {
+			tt.Parallel()
+
+			res, err := MuSig2CombineKeys(tc.keys, tc.tweak)
+
+			if tc.expectedErr != "" {
+				require.ErrorContains(tt, err, tc.expectedErr)
+				return
+			}
+
+			require.NoError(tt, err)
+
+			finalKey := res.FinalKey.SerializeCompressed()
+			preTweakKey := res.PreTweakedKey.SerializeCompressed()
+			require.Equal(
+				tt, tc.expectedFinalKey,
+				hex.EncodeToString(finalKey),
+			)
+			require.Equal(
+				tt, tc.expectedPreTweakKey,
+				hex.EncodeToString(preTweakKey),
+			)
+		})
+	}
+}