faster binding of snatives to vm (available every call)

state/execution.go

@@ -361,7 +361,6 @@ func ExecTx(blockCache *BlockCache, tx_ types.Tx, runCall bool, evc events.Firea
 
 	case *types.CallTx:
 		var inAcc, outAcc *account.Account
-		var isDoug bool // is this a call to the gendoug?
 
 		// Validate input
 		inAcc = blockCache.GetAccount(tx.Input.Address)
@@ -466,14 +465,11 @@ func ExecTx(blockCache *BlockCache, tx_ types.Tx, runCall bool, evc events.Firea
 			txCache.UpdateAccount(callee) // because we adjusted by input above.
 			vmach := vm.NewVM(txCache, params, caller.Address, account.HashSignBytes(_s.ChainID, tx))
 			vmach.SetFireable(evc)
-			vmach.EnablePermissions()
-			// NOTE: Call() transfers the value from caller to callee iff call succeeds.
 
-			if isDoug {
-				// enables the snative contracts
-				vmach.EnableDoug() // setupDoug(vmach, txCache, _s)
-			}
+			vmach.EnablePermissions() // permission checks on CALL/CREATE
+			vmach.EnableSNatives()    // allows calls to snatives (with permission checks)
 
+			// NOTE: Call() transfers the value from caller to callee iff call succeeds.
 			ret, err := vmach.Call(caller, callee, code, tx.Data, value, &gas)
 			exception := ""
 			if err != nil {

vm/snative.go

@@ -21,6 +21,7 @@ const (
 	// first 32 bits of BasePermission are for chain, second 32 are for snative
 	FirstSNativePerm ptypes.PermFlag = 1 << 32
 
+	// each snative has an associated permission flag
 	HasBasePerm ptypes.PermFlag = FirstSNativePerm << iota
 	SetBasePerm
 	UnsetBasePerm
@@ -35,8 +36,42 @@ const (
 	TopSNativePermission  ptypes.PermFlag = FirstSNativePerm << (NumSNativePermissions - 1)
 )
 
+var registeredSNativeContracts = map[Word256]ptypes.PermFlag{
+	RightPadWord256([]byte("hasBasePerm")):   HasBasePerm,
+	RightPadWord256([]byte("setBasePerm")):   SetBasePerm,
+	RightPadWord256([]byte("unsetBasePerm")): UnsetBasePerm,
+	RightPadWord256([]byte("setGlobalPerm")): SetGlobalPerm,
+	RightPadWord256([]byte("hasRole")):       HasRole,
+	RightPadWord256([]byte("addRole")):       AddRole,
+	RightPadWord256([]byte("rmRole")):        RmRole,
+}
+
+// takes an account so it can check for permission to access the contract
+// NOTE: the account is the currently executing account (the callee), not say an origin caller
 type SNativeContract func(acc *Account, input []byte) (output []byte, err error)
 
+func (vm *VM) SNativeContract(name Word256) SNativeContract {
+	flag := registeredSNativeContracts[name]
+	switch flag {
+	case HasBasePerm:
+		return vm.hasBasePerm
+	case SetBasePerm:
+		return vm.setBasePerm
+	case UnsetBasePerm:
+		return vm.unsetBasePerm
+	case SetGlobalPerm:
+		return vm.setGlobalPerm
+	case HasRole:
+		return vm.hasRole
+	case AddRole:
+		return vm.addRole
+	case RmRole:
+		return vm.rmRole
+	default:
+		return nil
+	}
+}
+
 //-----------------------------------------------------------------------------
 // snative are native contracts that can access and manipulate the chain state
 // (in particular the permissions values)

vm/vm.go

@@ -61,9 +61,8 @@ type VM struct {
 
 	evc events.Fireable
 
-	doug             bool // is this the gendoug contract
-	perms            bool // permission checking can be turned off
-	snativeContracts map[Word256]SNativeContract
+	perms   bool // permission checking can be turned off
+	snative bool // access to snatives
 }
 
 func NewVM(appState AppState, params Params, origin Word256, txid []byte) *VM {
@@ -73,7 +72,6 @@ func NewVM(appState AppState, params Params, origin Word256, txid []byte) *VM {
 		origin:    origin,
 		callDepth: 0,
 		txid:      txid,
-		doug:      false,
 	}
 }
 
@@ -83,17 +81,8 @@ func (vm *VM) SetFireable(evc events.Fireable) {
 }
 
 // to allow calls to native DougContracts (off by default)
-func (vm *VM) EnableDoug() {
-	vm.doug = true
-	vm.snativeContracts = map[Word256]SNativeContract{
-		RightPadWord256([]byte("hasBasePerm")):   vm.hasBasePerm,
-		RightPadWord256([]byte("setBasePerm")):   vm.setBasePerm,
-		RightPadWord256([]byte("unsetBasePerm")): vm.unsetBasePerm,
-		RightPadWord256([]byte("setGlobalPerm")): vm.setGlobalPerm,
-		RightPadWord256([]byte("hasRole")):       vm.hasRole,
-		RightPadWord256([]byte("addRole")):       vm.addRole,
-		RightPadWord256([]byte("rmRole")):        vm.rmRole,
-	}
+func (vm *VM) EnableSNatives() {
+	vm.snative = true
 }
 
 // run permission checks before call and create
@@ -757,9 +746,8 @@ func (vm *VM) call(caller, callee *Account, code, input []byte, value int64, gas
 			if nativeContract := nativeContracts[addr]; nativeContract != nil {
 				// Native contract
 				ret, err = nativeContract(args, &gasLimit)
-			} else if snativeContract := vm.snativeContracts[addr]; vm.doug && snativeContract != nil {
-				// This is Doug and we're calling a snative contract
-				// TODO: Doug contract should have all permissions
+			} else if snativeContract := vm.SNativeContract(addr); vm.snative && snativeContract != nil {
+				// Secure native contract (with access to chain state)
 				ret, err = snativeContract(callee, args)
 			} else {
 				// EVM contract