multi: add version to MuSig2 API, bump btcd/btcec to v2.3.2

With this commit we bump the github.com/btcd/btcec/v2 library to v2.3.2
which implements the MuSig2 BIP version v1.0.0rc2. With this the
github.com/btcsuite/btcd/btcec/v2/schnorr/musig2 package becomes
v1.0.0rc2 and the github.com/lightningnetwork/lnd/internal/musig2v040
stays at the old v0.4.0 version.

input/musig2_test.go

@@ -40,6 +40,19 @@ var (
 			"CA66",
 	))
 
+	testVector100Key1, _ = btcec.ParsePubKey(hexDecode(
+		"02F9308A019258C31049344F85F89D5229B531C845836F99B08601F113BC" +
+			"E036F9",
+	))
+	testVector100Key2, _ = btcec.ParsePubKey(hexDecode(
+		"03DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B50" +
+			"2BA659",
+	))
+	testVector100Key3, _ = btcec.ParsePubKey(hexDecode(
+		"023590A94E768F8E1815C2F24B4D80A8E3149316C3518CE7B7AD338368D0" +
+			"38CA66",
+	))
+
 	bip86Tweak = &MuSig2Tweaks{TaprootBIP0086Tweak: true}
 )
 
@@ -48,6 +61,7 @@ func TestMuSig2CombineKeys(t *testing.T) {
 
 	testCases := []struct {
 		name                string
+		version             MuSig2Version
 		keys                []*btcec.PublicKey
 		sortKeys            bool
 		tweak               *MuSig2Tweaks
@@ -55,16 +69,21 @@ func TestMuSig2CombineKeys(t *testing.T) {
 		expectedFinalKey    string
 		expectedPreTweakKey string
 	}{{
+		name:        "invalid version",
+		version:     7,
+		expectedErr: "unknown MuSig2 version: <7>",
+	}, {
 		name:     "v0.4.0 two dummy keys BIP86",
+		version:  MuSig2Version040,
 		keys:     []*btcec.PublicKey{dummyPubKey1, dummyPubKey2},
-		sortKeys: true,
-		tweak:    bip86Tweak,
+		sortKeys: true, tweak: bip86Tweak,
 		expectedFinalKey: "03b54fb320a8fc3589e86a1559c6aaa774fbab4e4d" +
 			"9fbf31e2fd836b661ac6a132",
 		expectedPreTweakKey: "0279c76a15dcf6786058a571e4022b78633e1bf" +
 			"8a7a4ca440bcbbeeaea772228a2",
 	}, {
-		name: "v0.4.0 three dummy keys BIP86",
+		name:    "v0.4.0 three dummy keys BIP86",
+		version: MuSig2Version040,
 		keys: []*btcec.PublicKey{
 			dummyPubKey1, dummyPubKey2, dummyPubKey3,
 		},
@@ -75,12 +94,13 @@ func TestMuSig2CombineKeys(t *testing.T) {
 		expectedPreTweakKey: "03e615b8aad4ed10544537bc48b1d6600e15773" +
 			"476a675c6cbba6808f21b1988e5",
 	}, {
-		name: "v0.4.0 three test vector keys BIP86",
+		name:    "v0.4.0 three test vector keys BIP86",
+		version: MuSig2Version040,
 		keys: []*btcec.PublicKey{
 			testVector040Key1, testVector040Key2, testVector040Key3,
 		},
-		sortKeys: true,
 		tweak:    bip86Tweak,
+		sortKeys: true,
 		expectedFinalKey: "025b257b4e785d61157ef5303051f45184bd5cb47b" +
 			"c4b4069ed4dd4536459cb83b",
 		expectedPreTweakKey: "02d70cd69a2647f7390973df48cbfa2ccc407b8" +
@@ -107,6 +127,54 @@ func TestMuSig2CombineKeys(t *testing.T) {
 			"dfdb788b3735b76a55538179",
 		expectedPreTweakKey: "03e5830140512195d74c8307e39637cbe5fb730" +
 			"ebeab80ec514cf88a877ceeee0b",
+	}, {
+		name:    "v1.0.0rc2 three dummy keys BIP86",
+		version: MuSig2Version100RC2,
+		keys: []*btcec.PublicKey{
+			dummyPubKey1, dummyPubKey2, dummyPubKey3,
+		},
+		sortKeys: true,
+		tweak:    bip86Tweak,
+		expectedFinalKey: "029d11a433e446276c88ee099cecfda1e4234dc486" +
+			"49e2b07f9b159176731eb68a",
+		expectedPreTweakKey: "03f0bacfef76086c519b6db216a252f1435336f" +
+			"d23fc86cfb51f67056439c256d4",
+	}, {
+		name:    "v1.0.0rc2 three test vector keys BIP86",
+		version: MuSig2Version100RC2,
+		keys: []*btcec.PublicKey{
+			testVector100Key1, testVector100Key2, testVector100Key3,
+		},
+		sortKeys: false,
+		tweak:    bip86Tweak,
+		expectedFinalKey: "03f79d14149ecd4bb74921865906a8e4f1333439a9" +
+			"1b96610d72caa7495dcf2376",
+		expectedPreTweakKey: "0290539eede565f5d054f32cc0c220126889ed1" +
+			"e5d193baf15aef344fe59d4610c",
+	}, {
+		name:    "v1.0.0rc2 three test vector keys BIP86 sorted",
+		version: MuSig2Version100RC2,
+		keys: []*btcec.PublicKey{
+			testVector100Key1, testVector100Key2, testVector100Key3,
+		},
+		sortKeys: true,
+		tweak:    bip86Tweak,
+		expectedFinalKey: "0379e6c3e628c9bfbce91de6b7fb28e2aec7713d37" +
+			"7cf260ab599dcbc40e542312",
+		expectedPreTweakKey: "03789d937bade6673538f3e28d8368dda4d0512" +
+			"f94da44cf477a505716d26a1575",
+	}, {
+		name:    "v1.0.0rc2 three test vector keys BIP86 reverse order",
+		version: MuSig2Version100RC2,
+		keys: []*btcec.PublicKey{
+			testVector100Key3, testVector100Key2, testVector100Key1,
+		},
+		sortKeys: false,
+		tweak:    bip86Tweak,
+		expectedFinalKey: "03d61d333ab8c53c330290c144f406ce0c0dc3564b" +
+			"8e3dee6d1daa6288609bfc75",
+		expectedPreTweakKey: "036204de8b083426dc6eaf9502d27024d53fc82" +
+			"6bf7d2012148a0575435df54b2b",
 	}}
 
 	for _, tc := range testCases {
@@ -115,7 +183,7 @@ func TestMuSig2CombineKeys(t *testing.T) {
 			tt.Parallel()
 
 			res, err := MuSig2CombineKeys(
-				tc.keys, tc.sortKeys, tc.tweak,
+				tc.version, tc.keys, tc.sortKeys, tc.tweak,
 			)
 
 			if tc.expectedErr != "" {