prysm-pulse/beacon-chain/state/stateutil/block_header_root.go
2021-03-18 16:29:06 -07:00

35 lines
1.3 KiB
Go

package stateutil
import (
"encoding/binary"
ethpb "github.com/prysmaticlabs/ethereumapis/eth/v1alpha1"
"github.com/prysmaticlabs/prysm/shared/bytesutil"
"github.com/prysmaticlabs/prysm/shared/hashutil"
"github.com/prysmaticlabs/prysm/shared/htrutils"
)
// BlockHeaderRoot computes the HashTreeRoot Merkleization of
// a BeaconBlockHeader struct according to the eth2
// Simple Serialize specification.
func BlockHeaderRoot(header *ethpb.BeaconBlockHeader) ([32]byte, error) {
fieldRoots := make([][]byte, 5)
if header != nil {
headerSlotBuf := make([]byte, 8)
binary.LittleEndian.PutUint64(headerSlotBuf, uint64(header.Slot))
headerSlotRoot := bytesutil.ToBytes32(headerSlotBuf)
fieldRoots[0] = headerSlotRoot[:]
proposerIdxBuf := make([]byte, 8)
binary.LittleEndian.PutUint64(proposerIdxBuf, uint64(header.ProposerIndex))
proposerIndexRoot := bytesutil.ToBytes32(proposerIdxBuf)
fieldRoots[1] = proposerIndexRoot[:]
parentRoot := bytesutil.ToBytes32(header.ParentRoot)
fieldRoots[2] = parentRoot[:]
stateRoot := bytesutil.ToBytes32(header.StateRoot)
fieldRoots[3] = stateRoot[:]
bodyRoot := bytesutil.ToBytes32(header.BodyRoot)
fieldRoots[4] = bodyRoot[:]
}
return htrutils.BitwiseMerkleize(hashutil.CustomSHA256Hasher(), fieldRoots, uint64(len(fieldRoots)), uint64(len(fieldRoots)))
}