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 EPostTicket struct { Partial []byte SectorID uint64 ChallengeIndex uint64 } type EPostProof struct { Proof []byte PostRand []byte Candidates []EPostTicket } type BlockHeader struct { Miner address.Address Ticket *Ticket EPostProof EPostProof 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) // Not sure i'm entirely comfortable with this one, needs to be checked } 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.Ticket } func (blk *BlockHeader) SigningBytes() ([]byte, error) { blkcopy := *blk blkcopy.BlockSig = nil return blkcopy.Serialize() } func (blk *BlockHeader) CheckBlockSignature(ctx context.Context, worker address.Address) error { _, 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) // also maybe sketchy } 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) const sha256bits = 256 func IsTicketWinner(partialTicket []byte, ssizeI uint64, snum uint64, totpow BigInt) bool { ssize := NewInt(ssizeI) ssampled := ElectionPostChallengeCount(snum) /* Need to check that (h(vrfout) + 1) / (max(h) + 1) <= e * sectorSize / totalPower max(h) == 2^256-1 which in terms of integer math means: (h(vrfout) + 1) * totalPower <= e * sectorSize * 2^256 in 2^256 space, it is equivalent to: h(vrfout) * totalPower < e * sectorSize * 2^256 Because of SectorChallengeRatioDiv sampling for proofs we need to scale this appropriately. Let c = ceil(numSectors/SectorChallengeRatioDiv) (c is the number of tickets a miner requests) Accordingly we check (h(vrfout) + 1) / 2^256 <= e * sectorSize / totalPower * snum / c or h(vrfout) * totalPower * c < e * sectorSize * 2^256 * snum */ h := sha256.Sum256(partialTicket) lhs := BigFromBytes(h[:]).Int lhs = lhs.Mul(lhs, totpow.Int) lhs = lhs.Mul(lhs, new(big.Int).SetUint64(ssampled)) // rhs = sectorSize * 2^256 // rhs = sectorSize << 256 rhs := new(big.Int).Lsh(ssize.Int, sha256bits) rhs = rhs.Mul(rhs, new(big.Int).SetUint64(snum)) rhs = rhs.Mul(rhs, blocksPerEpoch.Int) // h(vrfout) * totalPower < e * sectorSize * 2^256? return lhs.Cmp(rhs) < 0 } func ElectionPostChallengeCount(sectors uint64) uint64 { if sectors == 0 { return 0 } // ceil(sectors / build.SectorChallengeRatioDiv) return (sectors-1)/build.SectorChallengeRatioDiv + 1 } func (t *Ticket) Equals(ot *Ticket) bool { return bytes.Equal(t.VRFProof, ot.VRFProof) }