1 files changed, 44 insertions, 9 deletions
diff --git a/vm/address.go b/vm/address.go
index 235143b34..1c9369ab7 100644
--- a/vm/address.go
+++ b/vm/address.go
@@ -11,19 +11,46 @@ type Address interface {
 	Call(in []byte) []byte
 }
 
-type PrecompiledAddress struct {
-	Gas *big.Int
+type PrecompiledAccount struct {
+	Gas func(l int) *big.Int
 	fn  func(in []byte) []byte
 }
 
-func (self PrecompiledAddress) Call(in []byte) []byte {
+func (self PrecompiledAccount) Call(in []byte) []byte {
 	return self.fn(in)
 }
 
-var Precompiled = map[uint64]*PrecompiledAddress{
-	1: &PrecompiledAddress{big.NewInt(500), ecrecoverFunc},
-	2: &PrecompiledAddress{big.NewInt(100), sha256Func},
-	3: &PrecompiledAddress{big.NewInt(100), ripemd160Func},
+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(ethutil.LeftPadBytes([]byte{1}, 20)): &PrecompiledAccount{func(l int) *big.Int {
+			return GasEcrecover
+		}, ecrecoverFunc},
+
+		// SHA256
+		string(ethutil.LeftPadBytes([]byte{2}, 20)): &PrecompiledAccount{func(l int) *big.Int {
+			n := big.NewInt(int64(l+31)/32 + 1)
+			n.Mul(n, GasSha256)
+			return n
+		}, sha256Func},
+
+		// RIPEMD160
+		string(ethutil.LeftPadBytes([]byte{3}, 20)): &PrecompiledAccount{func(l int) *big.Int {
+			n := big.NewInt(int64(l+31)/32 + 1)
+			n.Mul(n, GasRipemd)
+			return n
+		}, ripemd160Func},
+
+		string(ethutil.LeftPadBytes([]byte{4}, 20)): &PrecompiledAccount{func(l int) *big.Int {
+			n := big.NewInt(int64(l+31)/32 + 1)
+			n.Mul(n, GasMemCpy)
+
+			return n
+		}, memCpy},
+	}
 }
 
 func sha256Func(in []byte) []byte {
@@ -31,12 +58,20 @@ func sha256Func(in []byte) []byte {
 }
 
 func ripemd160Func(in []byte) []byte {
-	return ethutil.RightPadBytes(crypto.Ripemd160(in), 32)
+	return ethutil.LeftPadBytes(crypto.Ripemd160(in), 32)
 }
 
 func ecrecoverFunc(in []byte) []byte {
 	// In case of an invalid sig. Defaults to return nil
 	defer func() { recover() }()
 
-	return crypto.Ecrecover(in)
+	hash := in[:32]
+	v := ethutil.BigD(in[32:64]).Bytes()[0] - 27
+	sig := append(in[64:], v)
+
+	return ethutil.LeftPadBytes(crypto.Sha3(crypto.Ecrecover(append(hash, sig...))[1:])[12:], 32)
+}
+
+func memCpy(in []byte) []byte {
+	return in
 }