This commit is contained in:
Jeffrey Wilcke 2017-02-24 12:00:01 +00:00 committed by GitHub
commit 26158a7129
6 changed files with 97 additions and 29 deletions

View file

@ -32,6 +32,7 @@ import (
var (
ExpDiffPeriod = big.NewInt(100000)
big9 = big.NewInt(9)
big10 = big.NewInt(10)
bigMinus99 = big.NewInt(-99)
)
@ -203,7 +204,7 @@ func (v *BlockValidator) ValidateHeader(header, parent *types.Header, checkPow b
// Validates a header. Returns an error if the header is invalid.
//
// See YP section 4.3.4. "Block Header Validity"
func ValidateHeader(config *params.ChainConfig, pow pow.PoW, header *types.Header, parent *types.Header, checkPow, uncle bool) error {
func ValidateHeader(config *params.ChainConfig, pow pow.PoW, header, parent *types.Header, checkPow, uncle bool) error {
if uint64(len(header.Extra)) > params.MaximumExtraDataSize {
return fmt.Errorf("Header extra data too long (%d)", len(header.Extra))
}
@ -221,7 +222,7 @@ func ValidateHeader(config *params.ChainConfig, pow pow.PoW, header *types.Heade
return BlockEqualTSErr
}
expd := CalcDifficulty(config, header.Time.Uint64(), parent.Time.Uint64(), parent.Number, parent.Difficulty)
expd := CalcDifficulty(config, header.Time.Uint64(), parent)
if expd.Cmp(header.Difficulty) != 0 {
return fmt.Errorf("Difficulty check failed for header (remote: %v local: %v)", header.Difficulty, expd)
}
@ -262,15 +263,64 @@ func ValidateHeader(config *params.ChainConfig, pow pow.PoW, header *types.Heade
// CalcDifficulty is the difficulty adjustment algorithm. It returns
// the difficulty that a new block should have when created at time
// given the parent block's time and difficulty.
func CalcDifficulty(config *params.ChainConfig, time, parentTime uint64, parentNumber, parentDiff *big.Int) *big.Int {
if config.IsHomestead(new(big.Int).Add(parentNumber, common.Big1)) {
return calcDifficultyHomestead(time, parentTime, parentNumber, parentDiff)
} else {
return calcDifficultyFrontier(time, parentTime, parentNumber, parentDiff)
func CalcDifficulty(config *params.ChainConfig, time uint64, parent *types.Header) *big.Int {
next := new(big.Int).Add(parent.Number, common.Big1)
switch {
case config.IsEIP100(next):
return CalcDifficultyMetropolis(time, parent)
case config.IsHomestead(next):
return calcDifficultyHomestead(time, parent)
default:
return calcDifficultyFrontier(time, parent)
}
}
func calcDifficultyHomestead(time, parentTime uint64, parentNumber, parentDiff *big.Int) *big.Int {
func CalcDifficultyMetropolis(time uint64, parent *types.Header) *big.Int {
bigTime := new(big.Int).SetUint64(time)
bigParentTime := new(big.Int).Set(parent.Time)
// adj_factor = max((2 if len(parent.uncles) else 1) - ((timestamp - parent.timestamp) // 9), -99)
var x *big.Int
if parent.UncleHash == types.EmptyUncleHash {
x = big.NewInt(1)
} else {
x = big.NewInt(2)
}
z := new(big.Int).Sub(bigTime, bigParentTime)
z.Div(x, big9)
x.Sub(x, z)
// max(1 - (block_timestamp - parent_timestamp) // 10, -99)))
if x.Cmp(bigMinus99) < 0 {
x.Set(bigMinus99)
}
// (parent_diff + parent_diff // 2048 * max(1 - (block_timestamp - parent_timestamp) // 10, -99))
y := new(big.Int).Div(parent.Difficulty, params.DifficultyBoundDivisor)
x.Mul(y, x)
x.Add(parent.Difficulty, x)
// minimum difficulty can ever be (before exponential factor)
if x.Cmp(params.MinimumDifficulty) < 0 {
x.Set(params.MinimumDifficulty)
}
// for the exponential factor
periodCount := new(big.Int).Add(parent.Number, common.Big1)
periodCount.Div(periodCount, ExpDiffPeriod)
// the exponential factor, commonly referred to as "the bomb"
// diff = diff + 2^(periodCount - 2)
if periodCount.Cmp(common.Big1) > 0 {
y.Sub(periodCount, common.Big2)
y.Exp(common.Big2, y, nil)
x.Add(x, y)
}
return x
}
func calcDifficultyHomestead(time uint64, parent *types.Header) *big.Int {
// https://github.com/ethereum/EIPs/blob/master/EIPS/eip-2.mediawiki
// algorithm:
// diff = (parent_diff +
@ -278,7 +328,7 @@ func calcDifficultyHomestead(time, parentTime uint64, parentNumber, parentDiff *
// ) + 2^(periodCount - 2)
bigTime := new(big.Int).SetUint64(time)
bigParentTime := new(big.Int).SetUint64(parentTime)
bigParentTime := new(big.Int).Set(parent.Time)
// holds intermediate values to make the algo easier to read & audit
x := new(big.Int)
@ -295,9 +345,9 @@ func calcDifficultyHomestead(time, parentTime uint64, parentNumber, parentDiff *
}
// (parent_diff + parent_diff // 2048 * max(1 - (block_timestamp - parent_timestamp) // 10, -99))
y.Div(parentDiff, params.DifficultyBoundDivisor)
y.Div(parent.Difficulty, params.DifficultyBoundDivisor)
x.Mul(y, x)
x.Add(parentDiff, x)
x.Add(parent.Difficulty, x)
// minimum difficulty can ever be (before exponential factor)
if x.Cmp(params.MinimumDifficulty) < 0 {
@ -305,7 +355,7 @@ func calcDifficultyHomestead(time, parentTime uint64, parentNumber, parentDiff *
}
// for the exponential factor
periodCount := new(big.Int).Add(parentNumber, common.Big1)
periodCount := new(big.Int).Add(parent.Number, common.Big1)
periodCount.Div(periodCount, ExpDiffPeriod)
// the exponential factor, commonly referred to as "the bomb"
@ -319,25 +369,25 @@ func calcDifficultyHomestead(time, parentTime uint64, parentNumber, parentDiff *
return x
}
func calcDifficultyFrontier(time, parentTime uint64, parentNumber, parentDiff *big.Int) *big.Int {
func calcDifficultyFrontier(time uint64, parent *types.Header) *big.Int {
diff := new(big.Int)
adjust := new(big.Int).Div(parentDiff, params.DifficultyBoundDivisor)
adjust := new(big.Int).Div(parent.Difficulty, params.DifficultyBoundDivisor)
bigTime := new(big.Int)
bigParentTime := new(big.Int)
bigTime.SetUint64(time)
bigParentTime.SetUint64(parentTime)
bigParentTime.Set(parent.Time)
if bigTime.Sub(bigTime, bigParentTime).Cmp(params.DurationLimit) < 0 {
diff.Add(parentDiff, adjust)
diff.Add(parent.Difficulty, adjust)
} else {
diff.Sub(parentDiff, adjust)
diff.Sub(parent.Difficulty, adjust)
}
if diff.Cmp(params.MinimumDifficulty) < 0 {
diff.Set(params.MinimumDifficulty)
}
periodCount := new(big.Int).Add(parentNumber, common.Big1)
periodCount := new(big.Int).Add(parent.Number, common.Big1)
periodCount.Div(periodCount, ExpDiffPeriod)
if periodCount.Cmp(common.Big1) > 0 {
// diff = diff + 2^(periodCount - 2)

View file

@ -165,7 +165,7 @@ func (b *BlockGen) OffsetTime(seconds int64) {
if b.header.Time.Cmp(b.parent.Header().Time) <= 0 {
panic("block time out of range")
}
b.header.Difficulty = CalcDifficulty(MakeChainConfig(), b.header.Time.Uint64(), b.parent.Time().Uint64(), b.parent.Number(), b.parent.Difficulty())
b.header.Difficulty = CalcDifficulty(MakeChainConfig(), b.header.Time.Uint64(), b.parent.Header())
}
// GenerateChain creates a chain of n blocks. The first block's
@ -233,11 +233,15 @@ func makeHeader(config *params.ChainConfig, parent *types.Block, state *state.St
} else {
time = new(big.Int).Add(parent.Time(), big.NewInt(10)) // block time is fixed at 10 seconds
}
parentHeader := parent.Header()
// adjust the parent time
parentHeader.Time = new(big.Int).Sub(time, big.NewInt(10))
return &types.Header{
Root: state.IntermediateRoot(config.IsEIP158(parent.Number())),
ParentHash: parent.Hash(),
Coinbase: parent.Coinbase(),
Difficulty: CalcDifficulty(MakeChainConfig(), time.Uint64(), new(big.Int).Sub(time, big.NewInt(10)).Uint64(), parent.Number(), parent.Difficulty()),
Difficulty: CalcDifficulty(MakeChainConfig(), time.Uint64(), parentHeader),
GasLimit: CalcGasLimit(parent),
GasUsed: new(big.Int),
Number: new(big.Int).Add(parent.Number(), common.Big1),

View file

@ -34,7 +34,7 @@ import (
)
type diffTest struct {
ParentTimestamp uint64
ParentTimestamp *big.Int
ParentDifficulty *big.Int
CurrentTimestamp uint64
CurrentBlocknumber *big.Int
@ -53,7 +53,7 @@ func (d *diffTest) UnmarshalJSON(b []byte) (err error) {
return err
}
d.ParentTimestamp = common.String2Big(ext.ParentTimestamp).Uint64()
d.ParentTimestamp = common.String2Big(ext.ParentTimestamp)
d.ParentDifficulty = common.String2Big(ext.ParentDifficulty)
d.CurrentTimestamp = common.String2Big(ext.CurrentTimestamp).Uint64()
d.CurrentBlocknumber = common.String2Big(ext.CurrentBlocknumber)
@ -78,7 +78,7 @@ func TestCalcDifficulty(t *testing.T) {
config := &params.ChainConfig{HomesteadBlock: big.NewInt(1150000)}
for name, test := range tests {
number := new(big.Int).Sub(test.CurrentBlocknumber, big.NewInt(1))
diff := CalcDifficulty(config, test.CurrentTimestamp, test.ParentTimestamp, number, test.ParentDifficulty)
diff := CalcDifficulty(config, test.CurrentTimestamp, &types.Header{Time: test.ParentTimestamp, Number: number, Difficulty: test.ParentDifficulty})
if diff.Cmp(test.CurrentDifficulty) != 0 {
t.Error(name, "failed. Expected", test.CurrentDifficulty, "and calculated", diff)
}

View file

@ -434,7 +434,7 @@ func (self *worker) commitNewWork() {
header := &types.Header{
ParentHash: parent.Hash(),
Number: num.Add(num, common.Big1),
Difficulty: core.CalcDifficulty(self.config, uint64(tstamp), parent.Time().Uint64(), parent.Number(), parent.Difficulty()),
Difficulty: core.CalcDifficulty(self.config, uint64(tstamp), parent.Header()),
GasLimit: core.CalcGasLimit(parent),
GasUsed: new(big.Int),
Coinbase: self.coinbase,

View file

@ -33,6 +33,7 @@ var MainnetChainConfig = &ChainConfig{
EIP150Hash: MainNetHomesteadGasRepriceHash,
EIP155Block: MainNetSpuriousDragon,
EIP158Block: MainNetSpuriousDragon,
EIP100Block: MainNetMetropolis,
}
// TestnetChainConfig is the chain parameters to run a node on the test network.
@ -45,6 +46,7 @@ var TestnetChainConfig = &ChainConfig{
EIP150Hash: common.HexToHash("0x41941023680923e0fe4d74a34bdac8141f2540e3ae90623718e47d66d1ca4a2d"),
EIP155Block: big.NewInt(10),
EIP158Block: big.NewInt(10),
EIP100Block: big.NewInt(11),
}
// ChainConfig is the core config which determines the blockchain settings.
@ -65,11 +67,12 @@ type ChainConfig struct {
EIP155Block *big.Int `json:"eip155Block"` // EIP155 HF block
EIP158Block *big.Int `json:"eip158Block"` // EIP158 HF block
EIP100Block *big.Int `json:"eip98Block"` // EIP100 HF block
}
// String implements the Stringer interface.
func (c *ChainConfig) String() string {
return fmt.Sprintf("{ChainID: %v Homestead: %v DAO: %v DAOSupport: %v EIP150: %v EIP155: %v EIP158: %v}",
return fmt.Sprintf("{ChainID: %v Homestead: %v DAO: %v DAOSupport: %v EIP150: %v EIP155: %v EIP158: %v, EIP100: %v}",
c.ChainId,
c.HomesteadBlock,
c.DAOForkBlock,
@ -77,11 +80,12 @@ func (c *ChainConfig) String() string {
c.EIP150Block,
c.EIP155Block,
c.EIP158Block,
c.EIP100Block,
)
}
var (
TestChainConfig = &ChainConfig{big.NewInt(1), new(big.Int), new(big.Int), true, new(big.Int), common.Hash{}, new(big.Int), new(big.Int)}
TestChainConfig = &ChainConfig{big.NewInt(1), new(big.Int), new(big.Int), true, new(big.Int), common.Hash{}, new(big.Int), new(big.Int), nil}
TestRules = TestChainConfig.Rules(new(big.Int))
)
@ -135,16 +139,23 @@ func (c *ChainConfig) IsEIP158(num *big.Int) bool {
}
func (c *ChainConfig) IsEIP100(num *big.Int) bool {
if c.EIP100Block == nil || num == nil {
return false
}
return num.Cmp(c.EIP100Block) >= 0
}
// Rules wraps ChainConfig and is merely syntatic sugar or can be used for functions
// that do not have or require information about the block.
//
// Rules is a one time interface meaning that it shouldn't be used in between transition
// phases.
type Rules struct {
ChainId *big.Int
IsHomestead, IsEIP150, IsEIP155, IsEIP158 bool
ChainId *big.Int
IsHomestead, IsEIP150, IsEIP155, IsEIP158, IsEIP100 bool
}
func (c *ChainConfig) Rules(num *big.Int) Rules {
return Rules{ChainId: new(big.Int).Set(c.ChainId), IsHomestead: c.IsHomestead(num), IsEIP150: c.IsEIP150(num), IsEIP155: c.IsEIP155(num), IsEIP158: c.IsEIP158(num)}
return Rules{ChainId: new(big.Int).Set(c.ChainId), IsHomestead: c.IsHomestead(num), IsEIP150: c.IsEIP150(num), IsEIP155: c.IsEIP155(num), IsEIP158: c.IsEIP158(num), IsEIP100: c.IsEIP100(num)}
}

View file

@ -38,6 +38,9 @@ var (
TestNetSpuriousDragon = big.NewInt(10)
MainNetSpuriousDragon = big.NewInt(2675000)
TestNetMetropolis = big.NewInt(11)
MainNetMetropolis = big.NewInt(10000000)
TestNetChainID = big.NewInt(3) // Test net default chain ID
MainNetChainID = big.NewInt(1) // main net default chain ID
)