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-rw-r--r--core/vm/contracts.go300
1 files changed, 272 insertions, 28 deletions
diff --git a/core/vm/contracts.go b/core/vm/contracts.go
index 43b60ba77..b885d42bb 100644
--- a/core/vm/contracts.go
+++ b/core/vm/contracts.go
@@ -22,14 +22,14 @@ import (
"math/big"
"github.com/ethereum/go-ethereum/common"
+ "github.com/ethereum/go-ethereum/common/math"
"github.com/ethereum/go-ethereum/crypto"
+ "github.com/ethereum/go-ethereum/crypto/bn256"
"github.com/ethereum/go-ethereum/params"
"golang.org/x/crypto/ripemd160"
)
-var errBadPrecompileInput = errors.New("bad pre compile input")
-
-// Precompiled contract is the basic interface for native Go contracts. The implementation
+// PrecompiledContract is the basic interface for native Go contracts. The implementation
// requires a deterministic gas count based on the input size of the Run method of the
// contract.
type PrecompiledContract interface {
@@ -37,48 +37,61 @@ type PrecompiledContract interface {
Run(input []byte) ([]byte, error) // Run runs the precompiled contract
}
-// PrecompiledContracts contains the default set of ethereum contracts
-var PrecompiledContracts = map[common.Address]PrecompiledContract{
+// PrecompiledContractsHomestead contains the default set of pre-compiled Ethereum
+// contracts used in the Frontier and Homestead releases.
+var PrecompiledContractsHomestead = map[common.Address]PrecompiledContract{
common.BytesToAddress([]byte{1}): &ecrecover{},
common.BytesToAddress([]byte{2}): &sha256hash{},
common.BytesToAddress([]byte{3}): &ripemd160hash{},
common.BytesToAddress([]byte{4}): &dataCopy{},
}
-// RunPrecompile runs and evaluate the output of a precompiled contract defined in contracts.go
+// PrecompiledContractsMetropolis contains the default set of pre-compiled Ethereum
+// contracts used in the Metropolis release.
+var PrecompiledContractsMetropolis = map[common.Address]PrecompiledContract{
+ common.BytesToAddress([]byte{1}): &ecrecover{},
+ common.BytesToAddress([]byte{2}): &sha256hash{},
+ common.BytesToAddress([]byte{3}): &ripemd160hash{},
+ common.BytesToAddress([]byte{4}): &dataCopy{},
+ common.BytesToAddress([]byte{5}): &bigModExp{},
+ common.BytesToAddress([]byte{6}): &bn256Add{},
+ common.BytesToAddress([]byte{7}): &bn256ScalarMul{},
+ common.BytesToAddress([]byte{8}): &bn256Pairing{},
+}
+
+// RunPrecompiledContract runs and evaluates the output of a precompiled contract.
func RunPrecompiledContract(p PrecompiledContract, input []byte, contract *Contract) (ret []byte, err error) {
gas := p.RequiredGas(input)
if contract.UseGas(gas) {
return p.Run(input)
- } else {
- return nil, ErrOutOfGas
}
+ return nil, ErrOutOfGas
}
-// ECRECOVER implemented as a native contract
+// ECRECOVER implemented as a native contract.
type ecrecover struct{}
func (c *ecrecover) RequiredGas(input []byte) uint64 {
return params.EcrecoverGas
}
-func (c *ecrecover) Run(in []byte) ([]byte, error) {
+func (c *ecrecover) Run(input []byte) ([]byte, error) {
const ecRecoverInputLength = 128
- in = common.RightPadBytes(in, ecRecoverInputLength)
- // "in" is (hash, v, r, s), each 32 bytes
+ input = common.RightPadBytes(input, ecRecoverInputLength)
+ // "input" is (hash, v, r, s), each 32 bytes
// but for ecrecover we want (r, s, v)
- r := new(big.Int).SetBytes(in[64:96])
- s := new(big.Int).SetBytes(in[96:128])
- v := in[63] - 27
+ r := new(big.Int).SetBytes(input[64:96])
+ s := new(big.Int).SetBytes(input[96:128])
+ v := input[63] - 27
- // tighter sig s values in homestead only apply to tx sigs
- if !allZero(in[32:63]) || !crypto.ValidateSignatureValues(v, r, s, false) {
+ // tighter sig s values input homestead only apply to tx sigs
+ if !allZero(input[32:63]) || !crypto.ValidateSignatureValues(v, r, s, false) {
return nil, nil
}
// v needs to be at the end for libsecp256k1
- pubKey, err := crypto.Ecrecover(in[:32], append(in[64:128], v))
+ pubKey, err := crypto.Ecrecover(input[:32], append(input[64:128], v))
// make sure the public key is a valid one
if err != nil {
return nil, nil
@@ -88,7 +101,7 @@ func (c *ecrecover) Run(in []byte) ([]byte, error) {
return common.LeftPadBytes(crypto.Keccak256(pubKey[1:])[12:], 32), nil
}
-// SHA256 implemented as a native contract
+// SHA256 implemented as a native contract.
type sha256hash struct{}
// RequiredGas returns the gas required to execute the pre-compiled contract.
@@ -96,14 +109,14 @@ type sha256hash struct{}
// This method does not require any overflow checking as the input size gas costs
// required for anything significant is so high it's impossible to pay for.
func (c *sha256hash) RequiredGas(input []byte) uint64 {
- return uint64(len(input)+31)/32*params.Sha256WordGas + params.Sha256Gas
+ return uint64(len(input)+31)/32*params.Sha256PerWordGas + params.Sha256BaseGas
}
-func (c *sha256hash) Run(in []byte) ([]byte, error) {
- h := sha256.Sum256(in)
+func (c *sha256hash) Run(input []byte) ([]byte, error) {
+ h := sha256.Sum256(input)
return h[:], nil
}
-// RIPMED160 implemented as a native contract
+// RIPMED160 implemented as a native contract.
type ripemd160hash struct{}
// RequiredGas returns the gas required to execute the pre-compiled contract.
@@ -111,15 +124,15 @@ type ripemd160hash struct{}
// This method does not require any overflow checking as the input size gas costs
// required for anything significant is so high it's impossible to pay for.
func (c *ripemd160hash) RequiredGas(input []byte) uint64 {
- return uint64(len(input)+31)/32*params.Ripemd160WordGas + params.Ripemd160Gas
+ return uint64(len(input)+31)/32*params.Ripemd160PerWordGas + params.Ripemd160BaseGas
}
-func (c *ripemd160hash) Run(in []byte) ([]byte, error) {
+func (c *ripemd160hash) Run(input []byte) ([]byte, error) {
ripemd := ripemd160.New()
- ripemd.Write(in)
+ ripemd.Write(input)
return common.LeftPadBytes(ripemd.Sum(nil), 32), nil
}
-// data copy implemented as a native contract
+// data copy implemented as a native contract.
type dataCopy struct{}
// RequiredGas returns the gas required to execute the pre-compiled contract.
@@ -127,8 +140,239 @@ type dataCopy struct{}
// This method does not require any overflow checking as the input size gas costs
// required for anything significant is so high it's impossible to pay for.
func (c *dataCopy) RequiredGas(input []byte) uint64 {
- return uint64(len(input)+31)/32*params.IdentityWordGas + params.IdentityGas
+ return uint64(len(input)+31)/32*params.IdentityPerWordGas + params.IdentityBaseGas
}
func (c *dataCopy) Run(in []byte) ([]byte, error) {
return in, nil
}
+
+// bigModExp implements a native big integer exponential modular operation.
+type bigModExp struct{}
+
+var (
+ big1 = big.NewInt(1)
+ big4 = big.NewInt(4)
+ big8 = big.NewInt(8)
+ big16 = big.NewInt(16)
+ big32 = big.NewInt(32)
+ big64 = big.NewInt(64)
+ big96 = big.NewInt(96)
+ big480 = big.NewInt(480)
+ big1024 = big.NewInt(1024)
+ big3072 = big.NewInt(3072)
+ big199680 = big.NewInt(199680)
+)
+
+// RequiredGas returns the gas required to execute the pre-compiled contract.
+func (c *bigModExp) RequiredGas(input []byte) uint64 {
+ var (
+ baseLen = new(big.Int).SetBytes(getData(input, 0, 32))
+ expLen = new(big.Int).SetBytes(getData(input, 32, 32))
+ modLen = new(big.Int).SetBytes(getData(input, 64, 32))
+ )
+ if len(input) > 96 {
+ input = input[96:]
+ } else {
+ input = input[:0]
+ }
+ // Retrieve the head 32 bytes of exp for the adjusted exponent length
+ var expHead *big.Int
+ if big.NewInt(int64(len(input))).Cmp(baseLen) <= 0 {
+ expHead = new(big.Int)
+ } else {
+ if expLen.Cmp(big32) > 0 {
+ expHead = new(big.Int).SetBytes(getData(input, baseLen.Uint64(), 32))
+ } else {
+ expHead = new(big.Int).SetBytes(getData(input, baseLen.Uint64(), expLen.Uint64()))
+ }
+ }
+ // Calculate the adjusted exponent length
+ var msb int
+ if bitlen := expHead.BitLen(); bitlen > 0 {
+ msb = bitlen - 1
+ }
+ adjExpLen := new(big.Int)
+ if expLen.Cmp(big32) > 0 {
+ adjExpLen.Sub(expLen, big32)
+ adjExpLen.Mul(big8, adjExpLen)
+ }
+ adjExpLen.Add(adjExpLen, big.NewInt(int64(msb)))
+
+ // Calculate the gas cost of the operation
+ gas := new(big.Int).Set(math.BigMax(modLen, baseLen))
+ switch {
+ case gas.Cmp(big64) <= 0:
+ gas.Mul(gas, gas)
+ case gas.Cmp(big1024) <= 0:
+ gas = new(big.Int).Add(
+ new(big.Int).Div(new(big.Int).Mul(gas, gas), big4),
+ new(big.Int).Sub(new(big.Int).Mul(big96, gas), big3072),
+ )
+ default:
+ gas = new(big.Int).Add(
+ new(big.Int).Div(new(big.Int).Mul(gas, gas), big16),
+ new(big.Int).Sub(new(big.Int).Mul(big480, gas), big199680),
+ )
+ }
+ gas.Mul(gas, math.BigMax(adjExpLen, big1))
+ gas.Div(gas, new(big.Int).SetUint64(params.ModExpQuadCoeffDiv))
+
+ if gas.BitLen() > 64 {
+ return math.MaxUint64
+ }
+ return gas.Uint64()
+}
+
+func (c *bigModExp) Run(input []byte) ([]byte, error) {
+ var (
+ baseLen = new(big.Int).SetBytes(getData(input, 0, 32)).Uint64()
+ expLen = new(big.Int).SetBytes(getData(input, 32, 32)).Uint64()
+ modLen = new(big.Int).SetBytes(getData(input, 64, 32)).Uint64()
+ )
+ if len(input) > 96 {
+ input = input[96:]
+ } else {
+ input = input[:0]
+ }
+ // Handle a special case when both the base and mod length is zero
+ if baseLen == 0 && modLen == 0 {
+ return []byte{}, nil
+ }
+ // Retrieve the operands and execute the exponentiation
+ var (
+ base = new(big.Int).SetBytes(getData(input, 0, baseLen))
+ exp = new(big.Int).SetBytes(getData(input, baseLen, expLen))
+ mod = new(big.Int).SetBytes(getData(input, baseLen+expLen, modLen))
+ )
+ if mod.BitLen() == 0 {
+ // Modulo 0 is undefined, return zero
+ return common.LeftPadBytes([]byte{}, int(modLen)), nil
+ }
+ return common.LeftPadBytes(base.Exp(base, exp, mod).Bytes(), int(modLen)), nil
+}
+
+var (
+ // errNotOnCurve is returned if a point being unmarshalled as a bn256 elliptic
+ // curve point is not on the curve.
+ errNotOnCurve = errors.New("point not on elliptic curve")
+
+ // errInvalidCurvePoint is returned if a point being unmarshalled as a bn256
+ // elliptic curve point is invalid.
+ errInvalidCurvePoint = errors.New("invalid elliptic curve point")
+)
+
+// newCurvePoint unmarshals a binary blob into a bn256 elliptic curve point,
+// returning it, or an error if the point is invalid.
+func newCurvePoint(blob []byte) (*bn256.G1, error) {
+ p, onCurve := new(bn256.G1).Unmarshal(blob)
+ if !onCurve {
+ return nil, errNotOnCurve
+ }
+ gx, gy, _, _ := p.CurvePoints()
+ if gx.Cmp(bn256.P) >= 0 || gy.Cmp(bn256.P) >= 0 {
+ return nil, errInvalidCurvePoint
+ }
+ return p, nil
+}
+
+// newTwistPoint unmarshals a binary blob into a bn256 elliptic curve point,
+// returning it, or an error if the point is invalid.
+func newTwistPoint(blob []byte) (*bn256.G2, error) {
+ p, onCurve := new(bn256.G2).Unmarshal(blob)
+ if !onCurve {
+ return nil, errNotOnCurve
+ }
+ x2, y2, _, _ := p.CurvePoints()
+ if x2.Real().Cmp(bn256.P) >= 0 || x2.Imag().Cmp(bn256.P) >= 0 ||
+ y2.Real().Cmp(bn256.P) >= 0 || y2.Imag().Cmp(bn256.P) >= 0 {
+ return nil, errInvalidCurvePoint
+ }
+ return p, nil
+}
+
+// bn256Add implements a native elliptic curve point addition.
+type bn256Add struct{}
+
+// RequiredGas returns the gas required to execute the pre-compiled contract.
+func (c *bn256Add) RequiredGas(input []byte) uint64 {
+ return params.Bn256AddGas
+}
+
+func (c *bn256Add) Run(input []byte) ([]byte, error) {
+ x, err := newCurvePoint(getData(input, 0, 64))
+ if err != nil {
+ return nil, err
+ }
+ y, err := newCurvePoint(getData(input, 64, 64))
+ if err != nil {
+ return nil, err
+ }
+ x.Add(x, y)
+ return x.Marshal(), nil
+}
+
+// bn256ScalarMul implements a native elliptic curve scalar multiplication.
+type bn256ScalarMul struct{}
+
+// RequiredGas returns the gas required to execute the pre-compiled contract.
+func (c *bn256ScalarMul) RequiredGas(input []byte) uint64 {
+ return params.Bn256ScalarMulGas
+}
+
+func (c *bn256ScalarMul) Run(input []byte) ([]byte, error) {
+ p, err := newCurvePoint(getData(input, 0, 64))
+ if err != nil {
+ return nil, err
+ }
+ p.ScalarMult(p, new(big.Int).SetBytes(getData(input, 64, 32)))
+ return p.Marshal(), nil
+}
+
+var (
+ // true32Byte is returned if the bn256 pairing check succeeds.
+ true32Byte = []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
+
+ // false32Byte is returned if the bn256 pairing check fails.
+ false32Byte = make([]byte, 32)
+
+ // errBadPairingInput is returned if the bn256 pairing input is invalid.
+ errBadPairingInput = errors.New("bad elliptic curve pairing size")
+)
+
+// bn256Pairing implements a pairing pre-compile for the bn256 curve
+type bn256Pairing struct{}
+
+// RequiredGas returns the gas required to execute the pre-compiled contract.
+func (c *bn256Pairing) RequiredGas(input []byte) uint64 {
+ return params.Bn256PairingBaseGas + uint64(len(input)/192)*params.Bn256PairingPerPointGas
+}
+
+func (c *bn256Pairing) Run(input []byte) ([]byte, error) {
+ // Handle some corner cases cheaply
+ if len(input)%192 > 0 {
+ return nil, errBadPairingInput
+ }
+ // Convert the input into a set of coordinates
+ var (
+ cs []*bn256.G1
+ ts []*bn256.G2
+ )
+ for i := 0; i < len(input); i += 192 {
+ c, err := newCurvePoint(input[i : i+64])
+ if err != nil {
+ return nil, err
+ }
+ t, err := newTwistPoint(input[i+64 : i+192])
+ if err != nil {
+ return nil, err
+ }
+ cs = append(cs, c)
+ ts = append(ts, t)
+ }
+ // Execute the pairing checks and return the results
+ ok := bn256.PairingCheck(cs, ts)
+ if ok {
+ return true32Byte, nil
+ }
+ return false32Byte, nil
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-03-25 17:45:45 +0800