// PrecompiledContracts returns the default set of precompiled ethereum
// contracts defined by the ethereum yellow paper.
func PrecompiledContracts() map[string]*PrecompiledAccount {
return map[string]*PrecompiledAccount{
// ECRECOVER
string(common.LeftPadBytes([]byte{1}, 20)): &PrecompiledAccount{func(l int) *big.Int {
return params.EcrecoverGas
}, ecrecoverFunc},
// SHA256
string(common.LeftPadBytes([]byte{2}, 20)): &PrecompiledAccount{func(l int) *big.Int {
n := big.NewInt(int64(l+31) / 32)
n.Mul(n, params.Sha256WordGas)
return n.Add(n, params.Sha256Gas)
}, sha256Func},
// RIPEMD160
string(common.LeftPadBytes([]byte{3}, 20)): &PrecompiledAccount{func(l int) *big.Int {
n := big.NewInt(int64(l+31) / 32)
n.Mul(n, params.Ripemd160WordGas)
return n.Add(n, params.Ripemd160Gas)
}, ripemd160Func},
string(common.LeftPadBytes([]byte{4}, 20)): &PrecompiledAccount{func(l int) *big.Int {
n := big.NewInt(int64(l+31) / 32)
n.Mul(n, params.IdentityWordGas)
return n.Add(n, params.IdentityGas)
}, memCpy},
}
}
// sha3 returns the canonical sha3 of the 32byte (padded) input
func sha3(in ...[]byte) []byte {
out := make([]byte, len(in)*32)
for i, input := range in {
copy(out[i*32:i*32+32], common.LeftPadBytes(input, 32))
}
return crypto.Sha3(out)
}
func ecrecoverFunc(in []byte) []byte {
in = common.RightPadBytes(in, 128)
// "in" is (hash, v, r, s), each 32 bytes
// but for ecrecover we want (r, s, v)
r := common.BytesToBig(in[64:96])
s := common.BytesToBig(in[96:128])
// Treat V as a 256bit integer
vbig := common.Bytes2Big(in[32:64])
v := byte(vbig.Uint64())
if !crypto.ValidateSignatureValues(v, r, s) {
glog.V(logger.Debug).Infof("EC RECOVER FAIL: v, r or s value invalid")
return nil
}
// v needs to be at the end and normalized for libsecp256k1
vbignormal := new(big.Int).Sub(vbig, big.NewInt(27))
vnormal := byte(vbignormal.Uint64())
rsv := append(in[64:128], vnormal)
pubKey, err := crypto.Ecrecover(in[:32], rsv)
// make sure the public key is a valid one
if err != nil {
glog.V(logger.Error).Infof("EC RECOVER FAIL: ", err)
return nil
}
// the first byte of pubkey is bitcoin heritage
return common.LeftPadBytes(crypto.Sha3(pubKey[1:])[12:], 32)
}
func opByte(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
th, val := stack.pop(), stack.pop()
if th.Cmp(big.NewInt(32)) < 0 {
byte := big.NewInt(int64(common.LeftPadBytes(val.Bytes(), 32)[th.Int64()]))
stack.push(byte)
} else {
stack.push(new(big.Int))
}
}
func Sign(hash []byte, prv *ecdsa.PrivateKey) (sig []byte, err error) {
if len(hash) != 32 {
return nil, fmt.Errorf("hash is required to be exactly 32 bytes (%d)", len(hash))
}
seckey := common.LeftPadBytes(prv.D.Bytes(), prv.Params().BitSize/8)
defer zeroBytes(seckey)
sig, err = secp256k1.Sign(hash, seckey)
return
}
// StdErrFormat formats a slice of StructLogs to human readable format
func StdErrFormat(logs []StructLog) {
fmt.Fprintf(os.Stderr, "VM STAT %d OPs\n", len(logs))
for _, log := range logs {
fmt.Fprintf(os.Stderr, "PC %08d: %s GAS: %v COST: %v", log.Pc, log.Op, log.Gas, log.GasCost)
if log.Err != nil {
fmt.Fprintf(os.Stderr, " ERROR: %v", log.Err)
}
fmt.Fprintf(os.Stderr, "\n")
fmt.Fprintln(os.Stderr, "STACK =", len(log.Stack))
for i := len(log.Stack) - 1; i >= 0; i-- {
fmt.Fprintf(os.Stderr, "%04d: %x\n", len(log.Stack)-i-1, common.LeftPadBytes(log.Stack[i].Bytes(), 32))
}
const maxMem = 10
addr := 0
fmt.Fprintln(os.Stderr, "MEM =", len(log.Memory))
for i := 0; i+16 <= len(log.Memory) && addr < maxMem; i += 16 {
data := log.Memory[i : i+16]
str := fmt.Sprintf("%04d: % x ", addr*16, data)
for _, r := range data {
if r == 0 {
str += "."
} else if unicode.IsPrint(rune(r)) {
str += fmt.Sprintf("%s", string(r))
} else {
str += "?"
}
}
addr++
fmt.Fprintln(os.Stderr, str)
}
fmt.Fprintln(os.Stderr, "STORAGE =", len(log.Storage))
for h, item := range log.Storage {
fmt.Fprintf(os.Stderr, "%x: %x\n", h, common.LeftPadBytes(item, 32))
}
fmt.Fprintln(os.Stderr)
}
}
func S256(n *big.Int) []byte {
sint := common.S256(n)
ret := common.LeftPadBytes(sint.Bytes(), 32)
if sint.Cmp(common.Big0) < 0 {
for i, b := range ret {
if b == 0 {
ret[i] = 1
continue
}
break
}
}
return ret
}
func ripemd160Func(in []byte) []byte {
return common.LeftPadBytes(crypto.Ripemd160(in), 32)
}
// Test the given input parameter `v` and checks if it matches certain
// criteria
// * Big integers are checks for ptr types and if the given value is
// assignable
// * Integer are checked for size
// * Strings, addresses and bytes are checks for type and size
func (t Type) pack(v interface{}) ([]byte, error) {
value := reflect.ValueOf(v)
switch kind := value.Kind(); kind {
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
if t.Type != ubig_t {
return nil, fmt.Errorf("type mismatch: %s for %T", t.Type, v)
}
return packNum(value, t.T), nil
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
if t.Type != ubig_t {
return nil, fmt.Errorf("type mismatch: %s for %T", t.Type, v)
}
return packNum(value, t.T), nil
case reflect.Ptr:
// If the value is a ptr do a assign check (only used by
// big.Int for now)
if t.Type == ubig_t && value.Type() != ubig_t {
return nil, fmt.Errorf("type mismatch: %s for %T", t.Type, v)
}
return packNum(value, t.T), nil
case reflect.String:
if t.Size > -1 && value.Len() > t.Size {
return nil, fmt.Errorf("%v out of bound. %d for %d", value.Kind(), value.Len(), t.Size)
}
return []byte(common.LeftPadString(t.String(), 32)), nil
case reflect.Slice:
if t.Size > -1 && value.Len() > t.Size {
return nil, fmt.Errorf("%v out of bound. %d for %d", value.Kind(), value.Len(), t.Size)
}
// Address is a special slice. The slice acts as one rather than a list of elements.
if t.T == AddressTy {
return common.LeftPadBytes(v.([]byte), 32), nil
}
// Signed / Unsigned check
if (t.T != IntTy && isSigned(value)) || (t.T == UintTy && isSigned(value)) {
return nil, fmt.Errorf("slice of incompatible types.")
}
var packed []byte
for i := 0; i < value.Len(); i++ {
packed = append(packed, packNum(value.Index(i), t.T)...)
}
return packed, nil
case reflect.Bool:
if value.Bool() {
return common.LeftPadBytes(common.Big1.Bytes(), 32), nil
} else {
return common.LeftPadBytes(common.Big0.Bytes(), 32), nil
}
case reflect.Array:
if v, ok := value.Interface().(common.Address); ok {
return common.LeftPadBytes(v[:], 32), nil
} else if v, ok := value.Interface().(common.Hash); ok {
return v[:], nil
}
}
return nil, fmt.Errorf("ABI: bad input given %v", value.Kind())
}
// U256 will ensure unsigned 256bit on big nums
func U256(n *big.Int) []byte {
return common.LeftPadBytes(common.U256(n).Bytes(), 32)
}