Remove unused Seal field from the extra data (#1379)

* Remove unused Seal field from the extra data

* Fix tests

* Update field comments

consensus/polybft/extra.go

@@ -28,7 +28,6 @@ var PolyBFTMixDigest = types.StringToHash("adce6e5230abe012342a44e4e9b6d05997d6f
 // Extra defines the structure of the extra field for Istanbul
 type Extra struct {
 	Validators *ValidatorSetDelta
-	Seal       []byte
 	Parent     *Signature
 	Committed  *Signature
 	Checkpoint *CheckpointData
@@ -52,21 +51,14 @@ func (i *Extra) MarshalRLPWith(ar *fastrlp.Arena) *fastrlp.Value {
 		vv.Set(i.Validators.MarshalRLPWith(ar))
 	}
 
-	// Seal
-	if len(i.Seal) == 0 {
-		vv.Set(ar.NewNull())
-	} else {
-		vv.Set(ar.NewBytes(i.Seal))
-	}
-
-	// ParentSeal
+	// Parent Signatures
 	if i.Parent == nil {
 		vv.Set(ar.NewNullArray())
 	} else {
 		vv.Set(i.Parent.MarshalRLPWith(ar))
 	}
 
-	// CommittedSeal
+	// Committed Signatures
 	if i.Committed == nil {
 		vv.Set(ar.NewNullArray())
 	} else {
@@ -90,7 +82,7 @@ func (i *Extra) UnmarshalRLP(input []byte) error {
 
 // UnmarshalRLPWith defines the unmarshal implementation for Extra
 func (i *Extra) UnmarshalRLPWith(v *fastrlp.Value) error {
-	const expectedElements = 5
+	const expectedElements = 4
 
 	elems, err := v.GetElems()
 	if err != nil {
@@ -109,33 +101,26 @@ func (i *Extra) UnmarshalRLPWith(v *fastrlp.Value) error {
 		}
 	}
 
-	// Seal
-	if elems[1].Len() > 0 {
-		if i.Seal, err = elems[1].GetBytes(i.Seal); err != nil {
-			return err
-		}
-	}
-
-	// Parent
-	if elems[2].Elems() > 0 {
+	// Parent Signatures
+	if elems[1].Elems() > 0 {
 		i.Parent = &Signature{}
-		if err := i.Parent.UnmarshalRLPWith(elems[2]); err != nil {
+		if err := i.Parent.UnmarshalRLPWith(elems[1]); err != nil {
 			return err
 		}
 	}
 
-	// Committed
-	if elems[3].Elems() > 0 {
+	// Committed Signatures
+	if elems[2].Elems() > 0 {
 		i.Committed = &Signature{}
-		if err := i.Committed.UnmarshalRLPWith(elems[3]); err != nil {
+		if err := i.Committed.UnmarshalRLPWith(elems[2]); err != nil {
 			return err
 		}
 	}
 
 	// Checkpoint
-	if elems[4].Elems() > 0 {
+	if elems[3].Elems() > 0 {
 		i.Checkpoint = &CheckpointData{}
-		if err := i.Checkpoint.UnmarshalRLPWith(elems[4]); err != nil {
+		if err := i.Checkpoint.UnmarshalRLPWith(elems[3]); err != nil {
 			return err
 		}
 	}
@@ -689,7 +674,6 @@ func GetIbftExtraClean(extraRaw []byte) ([]byte, error) {
 		Parent:     extra.Parent,
 		Validators: extra.Validators,
 		Checkpoint: extra.Checkpoint,
-		Seal:       []byte{},
 		Committed:  &Signature{},
 	}
 

consensus/polybft/extra_test.go

@@ -12,6 +12,7 @@ import (
 	"github.com/0xPolygon/polygon-edge/consensus/polybft/bitmap"
 	bls "github.com/0xPolygon/polygon-edge/consensus/polybft/signer"
 	"github.com/0xPolygon/polygon-edge/consensus/polybft/wallet"
+	"github.com/0xPolygon/polygon-edge/crypto"
 	"github.com/0xPolygon/polygon-edge/types"
 	"github.com/hashicorp/go-hclog"
 	"github.com/stretchr/testify/assert"
@@ -23,9 +24,17 @@ import (
 func TestExtra_Encoding(t *testing.T) {
 	t.Parallel()
 
-	parentStr := []byte("Here is the parent signature")
-	committedStr := []byte("Here is the committed signature")
-	bitmapStr := []byte("Here are the bitmap bytes")
+	digest := crypto.Keccak256([]byte("Dummy content to sign"))
+	keys := createRandomTestKeys(t, 2)
+	parentSig, err := keys[0].Sign(digest)
+	require.NoError(t, err)
+
+	committedSig, err := keys[1].Sign(digest)
+	require.NoError(t, err)
+
+	bmp := bitmap.Bitmap{}
+	bmp.Set(1)
+	bmp.Set(4)
 
 	addedValidators := newTestValidatorsWithAliases(t, []string{"A", "B", "C"}).getPublicIdentities()
 
@@ -49,7 +58,6 @@ func TestExtra_Encoding(t *testing.T) {
 		{
 			&Extra{
 				Validators: &ValidatorSetDelta{},
-				Seal:       []byte{3, 4},
 			},
 		},
 		{
@@ -66,7 +74,7 @@ func TestExtra_Encoding(t *testing.T) {
 				Validators: &ValidatorSetDelta{
 					Removed: removedValidators,
 				},
-				Parent:    &Signature{AggregatedSignature: parentStr, Bitmap: bitmapStr},
+				Parent:    &Signature{AggregatedSignature: parentSig, Bitmap: bmp},
 				Committed: &Signature{},
 			},
 		},
@@ -78,19 +86,19 @@ func TestExtra_Encoding(t *testing.T) {
 					Removed: removedValidators,
 				},
 				Parent:    &Signature{},
-				Committed: &Signature{AggregatedSignature: committedStr, Bitmap: bitmapStr},
+				Committed: &Signature{AggregatedSignature: committedSig, Bitmap: bmp},
 			},
 		},
 		{
 			&Extra{
-				Parent:    &Signature{AggregatedSignature: parentStr, Bitmap: bitmapStr},
-				Committed: &Signature{AggregatedSignature: committedStr, Bitmap: bitmapStr},
+				Parent:    &Signature{AggregatedSignature: parentSig, Bitmap: bmp},
+				Committed: &Signature{AggregatedSignature: committedSig, Bitmap: bmp},
 			},
 		},
 		{
 			&Extra{
-				Parent:    &Signature{AggregatedSignature: parentStr, Bitmap: bitmapStr},
-				Committed: &Signature{AggregatedSignature: committedStr, Bitmap: bitmapStr},
+				Parent:    &Signature{AggregatedSignature: parentSig, Bitmap: bmp},
+				Committed: &Signature{AggregatedSignature: committedSig, Bitmap: bmp},
 				Checkpoint: &CheckpointData{
 					BlockRound:            0,
 					EpochNumber:           3,
@@ -126,7 +134,7 @@ func TestExtra_UnmarshalRLPWith_NegativeCases(t *testing.T) {
 
 		extra := &Extra{}
 		ar := &fastrlp.Arena{}
-		require.ErrorContains(t, extra.UnmarshalRLPWith(ar.NewArray()), "incorrect elements count to decode Extra, expected 5 but found 0")
+		require.ErrorContains(t, extra.UnmarshalRLPWith(ar.NewArray()), "incorrect elements count to decode Extra, expected 4 but found 0")
 	})
 
 	t.Run("Incorrect ValidatorSetDelta marshalled", func(t *testing.T) {
@@ -152,7 +160,6 @@ func TestExtra_UnmarshalRLPWith_NegativeCases(t *testing.T) {
 		extraMarshalled := ar.NewArray()
 		deltaMarshalled := new(ValidatorSetDelta).MarshalRLPWith(ar)
 		extraMarshalled.Set(deltaMarshalled)       // ValidatorSetDelta
-		extraMarshalled.Set(ar.NewNull())          // Seal
 		extraMarshalled.Set(ar.NewBytes([]byte{})) // Parent
 		extraMarshalled.Set(ar.NewBytes([]byte{})) // Committed
 		require.Error(t, extra.UnmarshalRLPWith(extraMarshalled))

consensus/polybft/hash_test.go

@@ -15,7 +15,6 @@ func Test_setupHeaderHashFunc(t *testing.T) {
 		Validators: &ValidatorSetDelta{Removed: bitmap.Bitmap{1}},
 		Parent:     createSignature(t, []*wallet.Account{generateTestAccount(t)}, types.ZeroHash, bls.DomainCheckpointManager),
 		Checkpoint: &CheckpointData{},
-		Seal:       []byte{},
 		Committed:  &Signature{},
 	}
 
@@ -28,7 +27,6 @@ func Test_setupHeaderHashFunc(t *testing.T) {
 	header.ExtraData = append(make([]byte, ExtraVanity), extra.MarshalRLPTo(nil)...)
 	notFullExtraHash := types.HeaderHash(header)
 
-	extra.Seal = []byte{1, 2, 3, 255}
 	extra.Committed = createSignature(t, []*wallet.Account{generateTestAccount(t)}, types.ZeroHash, bls.DomainCheckpointManager)
 	header.ExtraData = append(make([]byte, ExtraVanity), extra.MarshalRLPTo(nil)...)
 	fullExtraHash := types.HeaderHash(header)

consensus/polybft/polybft_test.go

@@ -41,7 +41,6 @@ func TestPolybft_VerifyHeader(t *testing.T) {
 			Parent:     parentSignature,
 			Checkpoint: checkpointData,
 			Committed:  &Signature{},
-			Seal:       []byte{},
 		}
 
 		if extra.Checkpoint == nil {