forked from cerc-io/plugeth
92 lines
2.2 KiB
Go
92 lines
2.2 KiB
Go
package vm
|
|
|
|
import (
|
|
"math/big"
|
|
|
|
"github.com/ethereum/go-ethereum/common"
|
|
"github.com/ethereum/go-ethereum/crypto"
|
|
)
|
|
|
|
type Address interface {
|
|
Call(in []byte) []byte
|
|
}
|
|
|
|
type PrecompiledAccount struct {
|
|
Gas func(l int) *big.Int
|
|
fn func(in []byte) []byte
|
|
}
|
|
|
|
func (self PrecompiledAccount) Call(in []byte) []byte {
|
|
return self.fn(in)
|
|
}
|
|
|
|
var Precompiled = PrecompiledContracts()
|
|
|
|
// XXX Could set directly. Testing requires resetting and setting of pre compiled contracts.
|
|
func PrecompiledContracts() map[string]*PrecompiledAccount {
|
|
return map[string]*PrecompiledAccount{
|
|
// ECRECOVER
|
|
string(common.LeftPadBytes([]byte{1}, 20)): &PrecompiledAccount{func(l int) *big.Int {
|
|
return GasEcrecover
|
|
}, ecrecoverFunc},
|
|
|
|
// SHA256
|
|
string(common.LeftPadBytes([]byte{2}, 20)): &PrecompiledAccount{func(l int) *big.Int {
|
|
n := big.NewInt(int64(l+31) / 32)
|
|
n.Mul(n, GasSha256Word)
|
|
return n.Add(n, GasSha256Base)
|
|
}, sha256Func},
|
|
|
|
// RIPEMD160
|
|
string(common.LeftPadBytes([]byte{3}, 20)): &PrecompiledAccount{func(l int) *big.Int {
|
|
n := big.NewInt(int64(l+31) / 32)
|
|
n.Mul(n, GasRipemdWord)
|
|
return n.Add(n, GasRipemdBase)
|
|
}, ripemd160Func},
|
|
|
|
string(common.LeftPadBytes([]byte{4}, 20)): &PrecompiledAccount{func(l int) *big.Int {
|
|
n := big.NewInt(int64(l+31) / 32)
|
|
n.Mul(n, GasIdentityWord)
|
|
|
|
return n.Add(n, GasIdentityBase)
|
|
}, memCpy},
|
|
}
|
|
}
|
|
|
|
func sha256Func(in []byte) []byte {
|
|
return crypto.Sha256(in)
|
|
}
|
|
|
|
func ripemd160Func(in []byte) []byte {
|
|
return common.LeftPadBytes(crypto.Ripemd160(in), 32)
|
|
}
|
|
|
|
const EcRecoverInputLength = 128
|
|
|
|
func ecrecoverFunc(in []byte) []byte {
|
|
// "in" is (hash, v, r, s), each 32 bytes
|
|
// but for ecrecover we want (r, s, v)
|
|
if len(in) < EcRecoverInputLength {
|
|
return nil
|
|
}
|
|
hash := in[:32]
|
|
// v is only a bit, but comes as 32 bytes from vm. We only need least significant byte
|
|
encodedV := in[32:64]
|
|
v := encodedV[31] - 27
|
|
if !(v == 0 || v == 1) {
|
|
return nil
|
|
}
|
|
sig := append(in[64:], v)
|
|
pubKey := crypto.Ecrecover(append(hash, sig...))
|
|
// secp256.go returns either nil or 65 bytes
|
|
if pubKey == nil || len(pubKey) != 65 {
|
|
return nil
|
|
}
|
|
// the first byte of pubkey is bitcoin heritage
|
|
return common.LeftPadBytes(crypto.Sha3(pubKey[1:])[12:], 32)
|
|
}
|
|
|
|
func memCpy(in []byte) []byte {
|
|
return in
|
|
}
|