lotus/chain/types/blockheader.go
Łukasz Magiera e98feb4a39 fix PowerCmp
2019-10-28 21:28:01 +01:00

192 lines
3.5 KiB
Go

package types
import (
"bytes"
"context"
"math/big"
block "github.com/ipfs/go-block-format"
"github.com/ipfs/go-cid"
"github.com/minio/sha256-simd"
"github.com/multiformats/go-multihash"
"go.opencensus.io/trace"
xerrors "golang.org/x/xerrors"
"github.com/filecoin-project/lotus/build"
"github.com/filecoin-project/lotus/chain/address"
)
type Ticket struct {
VRFProof []byte
}
type ElectionProof []byte
type BlockHeader struct {
Miner address.Address
Tickets []*Ticket
ElectionProof []byte
Parents []cid.Cid
ParentWeight BigInt
Height uint64
ParentStateRoot cid.Cid
ParentMessageReceipts cid.Cid
Messages cid.Cid
BLSAggregate Signature
Timestamp uint64
BlockSig Signature
}
func (b *BlockHeader) ToStorageBlock() (block.Block, error) {
data, err := b.Serialize()
if err != nil {
return nil, err
}
pref := cid.NewPrefixV1(cid.DagCBOR, multihash.BLAKE2B_MIN+31)
c, err := pref.Sum(data)
if err != nil {
return nil, err
}
return block.NewBlockWithCid(data, c)
}
func (b *BlockHeader) Cid() cid.Cid {
sb, err := b.ToStorageBlock()
if err != nil {
panic(err)
}
return sb.Cid()
}
func DecodeBlock(b []byte) (*BlockHeader, error) {
var blk BlockHeader
if err := blk.UnmarshalCBOR(bytes.NewReader(b)); err != nil {
return nil, err
}
return &blk, nil
}
func (blk *BlockHeader) Serialize() ([]byte, error) {
buf := new(bytes.Buffer)
if err := blk.MarshalCBOR(buf); err != nil {
return nil, err
}
return buf.Bytes(), nil
}
func (blk *BlockHeader) LastTicket() *Ticket {
return blk.Tickets[len(blk.Tickets)-1]
}
func (blk *BlockHeader) SigningBytes() ([]byte, error) {
blkcopy := *blk
blkcopy.BlockSig = Signature{}
return blkcopy.Serialize()
}
func (blk *BlockHeader) CheckBlockSignature(ctx context.Context, worker address.Address) error {
ctx, span := trace.StartSpan(ctx, "checkBlockSignature")
defer span.End()
sigb, err := blk.SigningBytes()
if err != nil {
return xerrors.Errorf("failed to get block signing bytes: %w", err)
}
return blk.BlockSig.Verify(worker, sigb)
}
type MsgMeta struct {
BlsMessages cid.Cid
SecpkMessages cid.Cid
}
func (mm *MsgMeta) Cid() cid.Cid {
b, err := mm.ToStorageBlock()
if err != nil {
panic(err)
}
return b.Cid()
}
func (mm *MsgMeta) ToStorageBlock() (block.Block, error) {
buf := new(bytes.Buffer)
if err := mm.MarshalCBOR(buf); err != nil {
return nil, xerrors.Errorf("failed to marshal MsgMeta: %w", err)
}
pref := cid.NewPrefixV1(cid.DagCBOR, multihash.BLAKE2B_MIN+31)
c, err := pref.Sum(buf.Bytes())
if err != nil {
return nil, err
}
return block.NewBlockWithCid(buf.Bytes(), c)
}
func CidArrsEqual(a, b []cid.Cid) bool {
if len(a) != len(b) {
return false
}
// order ignoring compare...
s := make(map[cid.Cid]bool)
for _, c := range a {
s[c] = true
}
for _, c := range b {
if !s[c] {
return false
}
}
return true
}
var blocksPerEpoch = NewInt(build.BlocksPerEpoch)
func PowerCmp(eproof ElectionProof, mpow, totpow BigInt) bool {
/*
Need to check that
h(vrfout) / max(h) < e * minerPower / totalPower
max(h) == 2^256-1
which in terms of integer math means:
h(vrfout) * totalPower < e * minerPower * (2^256-1)
*/
h := sha256.Sum256(eproof)
lhs := BigFromBytes(h[:]).Int
lhs = lhs.Mul(lhs, totpow.Int)
// rhs = minerPower * 2^256 - minerPower
// rhs = minerPower << 256 - minerPower
rhs := new(big.Int).Lsh(mpow.Int, 256)
rhs = rhs.Mul(rhs, blocksPerEpoch.Int)
rhs = rhs.Sub(rhs, mpow.Int)
return lhs.Cmp(rhs) == -1
}
func (t *Ticket) Equals(ot *Ticket) bool {
return bytes.Equal(t.VRFProof, ot.VRFProof)
}