protocol/validation/block.go

   1 package validation
   2
   3 import (
   4         "time"
   5
   6         log "github.com/sirupsen/logrus"
   7
   8         "github.com/vapor/chain"
   9         "github.com/vapor/consensus"
  10         engine "github.com/vapor/consensus/consensus"
  11         "github.com/vapor/errors"
  12         "github.com/vapor/protocol/bc"
  13         "github.com/vapor/protocol/bc/types"
  14         "github.com/vapor/protocol/state"
  15 )
  16
  17 const logModule = "leveldb"
  18
  19 var (
  20         errBadTimestamp          = errors.New("block timestamp is not in the valid range")
  21         errBadBits               = errors.New("block bits is invalid")
  22         errMismatchedBlock       = errors.New("mismatched block")
  23         errMismatchedMerkleRoot  = errors.New("mismatched merkle root")
  24         errMisorderedBlockHeight = errors.New("misordered block height")
  25         errOverBlockLimit        = errors.New("block's gas is over the limit")
  26         errWorkProof             = errors.New("invalid difficulty proof of work")
  27         errVersionRegression     = errors.New("version regression")
  28 )
  29
  30 func checkBlockTime(b *bc.Block, parent *state.BlockNode) error {
  31         if b.Timestamp > uint64(time.Now().Unix())+consensus.MaxTimeOffsetSeconds {
  32                 return errBadTimestamp
  33         }
  34
  35         if b.Timestamp <= parent.CalcPastMedianTime() {
  36                 return errBadTimestamp
  37         }
  38         return nil
  39 }
  40
  41 func checkCoinbaseAmount(b *bc.Block, amount uint64) error {
  42         if len(b.Transactions) == 0 {
  43                 return errors.Wrap(ErrWrongCoinbaseTransaction, "block is empty")
  44         }
  45
  46         tx := b.Transactions[0]
  47         output, err := tx.Output(*tx.TxHeader.ResultIds[0])
  48         if err != nil {
  49                 return err
  50         }
  51
  52         if output.Source.Value.Amount != amount {
  53                 return errors.Wrap(ErrWrongCoinbaseTransaction, "dismatch output amount")
  54         }
  55         return nil
  56 }
  57
  58 // ValidateBlockHeader check the block's header
  59 func ValidateBlockHeader(b *bc.Block, block *types.Block, parent *state.BlockNode, c chain.Chain, engine engine.Engine) error {
  60         if b.Version < parent.Version {
  61                 return errors.WithDetailf(errVersionRegression, "previous block verson %d, current block version %d", parent.Version, b.Version)
  62         }
  63         if b.Height != parent.Height+1 {
  64                 return errors.WithDetailf(errMisorderedBlockHeight, "previous block height %d, current block height %d", parent.Height, b.Height)
  65         }
  66         if parent.Hash != *b.PreviousBlockId {
  67                 return errors.WithDetailf(errMismatchedBlock, "previous block ID %x, current block wants %x", parent.Hash.Bytes(), b.PreviousBlockId.Bytes())
  68         }
  69         if err := checkBlockTime(b, parent); err != nil {
  70                 return err
  71         }
  72         if err := engine.VerifySeal(c, &block.BlockHeader); err != nil {
  73                 return err
  74         }
  75
  76         return nil
  77 }
  78
  79 // ValidateBlock validates a block and the transactions within.
  80 func ValidateBlock(b *bc.Block, parent *state.BlockNode, block *types.Block, c chain.Chain, engine engine.Engine) error {
  81         startTime := time.Now()
  82         if err := ValidateBlockHeader(b, block, parent, c, engine); err != nil {
  83                 return err
  84         }
  85
  86         blockGasSum := uint64(0)
  87         coinbaseAmount := consensus.BlockSubsidy(b.BlockHeader.Height)
  88         b.TransactionStatus = bc.NewTransactionStatus()
  89         for i, tx := range b.Transactions {
  90                 gasStatus, err := ValidateTx(tx, b)
  91                 if !gasStatus.GasValid {
  92                         return errors.Wrapf(err, "validate of transaction %d of %d", i, len(b.Transactions))
  93                 }
  94
  95                 if err := b.TransactionStatus.SetStatus(i, err != nil); err != nil {
  96                         return err
  97                 }
  98                 coinbaseAmount += gasStatus.BTMValue
  99                 if blockGasSum += uint64(gasStatus.GasUsed); blockGasSum > consensus.MaxBlockGas {
 100                         return errOverBlockLimit
 101                 }
 102         }
 103
 104         if err := checkCoinbaseAmount(b, coinbaseAmount); err != nil {
 105                 return err
 106         }
 107
 108         txMerkleRoot, err := types.TxMerkleRoot(b.Transactions)
 109         if err != nil {
 110                 return errors.Wrap(err, "computing transaction id merkle root")
 111         }
 112         if txMerkleRoot != *b.TransactionsRoot {
 113                 return errors.WithDetailf(errMismatchedMerkleRoot, "transaction id merkle root")
 114         }
 115
 116         txStatusHash, err := types.TxStatusMerkleRoot(b.TransactionStatus.VerifyStatus)
 117         if err != nil {
 118                 return errors.Wrap(err, "computing transaction status merkle root")
 119         }
 120         if txStatusHash != *b.TransactionStatusHash {
 121                 return errors.WithDetailf(errMismatchedMerkleRoot, "transaction status merkle root")
 122         }
 123
 124         log.WithFields(log.Fields{
 125                 "module":   logModule,
 126                 "height":   b.Height,
 127                 "hash":     b.ID.String(),
 128                 "duration": time.Since(startTime),
 129         }).Debug("finish validate block")
 130         return nil
 131 }