Add new DomainType for application usage (#10740)

* Add new DomainType for application usage

* Add DomainApplicationMask to config_test

* Add func to convert uint32 to 4 byte array

We add a convenience function Uint32ToBytes4 that takes a uint32,
converts it to big endian order and return a 4 byte array.

* Add unit test for Uint32ToBytes4

Co-authored-by: Raul Jordan <raul@prysmaticlabs.com>
Co-authored-by: terencechain <terence@prysmaticlabs.com>

beacon-chain/rpc/eth/beacon/config_test.go

@@ -123,6 +123,9 @@ func TestGetSpec(t *testing.T) {
 	var daap [4]byte
 	copy(daap[:], []byte{'0', '0', '0', '7'})
 	config.DomainAggregateAndProof = daap
+	var dam [4]byte
+	copy(dam[:], []byte{'1', '0', '0', '0'})
+	config.DomainApplicationMask = dam
 
 	params.OverrideBeaconConfig(config)
 
@@ -130,7 +133,7 @@ func TestGetSpec(t *testing.T) {
 	resp, err := server.GetSpec(context.Background(), &emptypb.Empty{})
 	require.NoError(t, err)
 
-	assert.Equal(t, 98, len(resp.Data))
+	assert.Equal(t, 99, len(resp.Data))
 	for k, v := range resp.Data {
 		switch k {
 		case "CONFIG_NAME":
@@ -315,6 +318,8 @@ func TestGetSpec(t *testing.T) {
 			assert.Equal(t, "0x30303036", v)
 		case "DOMAIN_AGGREGATE_AND_PROOF":
 			assert.Equal(t, "0x30303037", v)
+		case "DOMAIN_APPLICATION_MASK":
+			assert.Equal(t, "0x31303030", v)
 		case "DOMAIN_SYNC_COMMITTEE":
 			assert.Equal(t, "0x07000000", v)
 		case "DOMAIN_SYNC_COMMITTEE_SELECTION_PROOF":

config/params/config.go

@@ -110,6 +110,7 @@ type BeaconChainConfig struct {
 	DomainSyncCommittee               [4]byte `yaml:"DOMAIN_SYNC_COMMITTEE" spec:"true"`                 // DomainVoluntaryExit defines the BLS signature domain for sync committee.
 	DomainSyncCommitteeSelectionProof [4]byte `yaml:"DOMAIN_SYNC_COMMITTEE_SELECTION_PROOF" spec:"true"` // DomainSelectionProof defines the BLS signature domain for sync committee selection proof.
 	DomainContributionAndProof        [4]byte `yaml:"DOMAIN_CONTRIBUTION_AND_PROOF" spec:"true"`         // DomainAggregateAndProof defines the BLS signature domain for contribution and proof.
+	DomainApplicationMask             [4]byte `yaml:"DOMAIN_APPLICATION_MASK" spec:"true"`               // DomainApplicationMask defines the BLS signature domain for application mask.
 
 	// Prysm constants.
 	GweiPerEth                     uint64        // GweiPerEth is the amount of gwei corresponding to 1 eth.

config/params/mainnet_config.go

@@ -155,16 +155,17 @@ var mainnetBeaconConfig = &BeaconChainConfig{
 	MaxVoluntaryExits:    16,
 
 	// BLS domain values.
-	DomainBeaconProposer:              bytesutil.ToBytes4(bytesutil.Bytes4(0)),
-	DomainBeaconAttester:              bytesutil.ToBytes4(bytesutil.Bytes4(1)),
-	DomainRandao:                      bytesutil.ToBytes4(bytesutil.Bytes4(2)),
-	DomainDeposit:                     bytesutil.ToBytes4(bytesutil.Bytes4(3)),
-	DomainVoluntaryExit:               bytesutil.ToBytes4(bytesutil.Bytes4(4)),
-	DomainSelectionProof:              bytesutil.ToBytes4(bytesutil.Bytes4(5)),
-	DomainAggregateAndProof:           bytesutil.ToBytes4(bytesutil.Bytes4(6)),
-	DomainSyncCommittee:               bytesutil.ToBytes4(bytesutil.Bytes4(7)),
-	DomainSyncCommitteeSelectionProof: bytesutil.ToBytes4(bytesutil.Bytes4(8)),
-	DomainContributionAndProof:        bytesutil.ToBytes4(bytesutil.Bytes4(9)),
+	DomainBeaconProposer:              bytesutil.Uint32ToBytes4(0x00000000),
+	DomainBeaconAttester:              bytesutil.Uint32ToBytes4(0x01000000),
+	DomainRandao:                      bytesutil.Uint32ToBytes4(0x02000000),
+	DomainDeposit:                     bytesutil.Uint32ToBytes4(0x03000000),
+	DomainVoluntaryExit:               bytesutil.Uint32ToBytes4(0x04000000),
+	DomainSelectionProof:              bytesutil.Uint32ToBytes4(0x05000000),
+	DomainAggregateAndProof:           bytesutil.Uint32ToBytes4(0x06000000),
+	DomainSyncCommittee:               bytesutil.Uint32ToBytes4(0x07000000),
+	DomainSyncCommitteeSelectionProof: bytesutil.Uint32ToBytes4(0x08000000),
+	DomainContributionAndProof:        bytesutil.Uint32ToBytes4(0x09000000),
+	DomainApplicationMask:             bytesutil.Uint32ToBytes4(0x00000001),
 
 	// Prysm constants.
 	GweiPerEth:                     1000000000,

encoding/bytesutil/bytes.go

@@ -339,6 +339,14 @@ func HighestBitIndexAt(b []byte, index int) (int, error) {
 	return 0, nil
 }
 
+// Uint32ToBytes4 is a convenience method for converting uint32 to a fix
+// sized 4 byte array in big endian order. Returns 4 byte array.
+func Uint32ToBytes4(i uint32) [4]byte {
+	buf := make([]byte, 4)
+	binary.BigEndian.PutUint32(buf, i)
+	return ToBytes4(buf)
+}
+
 // Uint64ToBytesLittleEndian conversion.
 func Uint64ToBytesLittleEndian(i uint64) []byte {
 	buf := make([]byte, 8)

encoding/bytesutil/bytes_test.go

@@ -2,6 +2,7 @@ package bytesutil_test
 
 import (
 	"bytes"
+	"fmt"
 	"reflect"
 	"testing"
 
@@ -582,3 +583,26 @@ func TestIsValidRoot(t *testing.T) {
 		})
 	}
 }
+
+func TestUint32ToBytes4(t *testing.T) {
+	tests := []struct {
+		value uint32
+		want  [4]byte
+	}{
+		{
+			value: 0x01000000,
+			want:  [4]byte{1, 0, 0, 0},
+		},
+		{
+			value: 0x00000001,
+			want:  [4]byte{0, 0, 0, 1},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(fmt.Sprintf("0x%08x", tt.value), func(t *testing.T) {
+			if got := bytesutil.Uint32ToBytes4(tt.value); !bytes.Equal(got[:], tt.want[:]) {
+				t.Errorf("Uint32ToBytes4() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}