[#174] subnet: Add RemoveUser method

Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>

subnet/subnet_contract.go

@@ -31,6 +31,8 @@ const (
 	ErrClientAdmNotExist = "client admin not found"
 	// ErrNodeNotExist is thrown when node is not found.
 	ErrNodeNotExist = "node not found"
+	// ErrUserNotExist is thrown when user is not found.
+	ErrUserNotExist = "user not found"
 	// ErrAccessDenied is thrown when operation is denied for caller.
 	ErrAccessDenied = "access denied"
 
@@ -228,32 +230,19 @@ func AddNode(subnetID []byte, node interop.PublicKey) {
 	ctx := storage.GetContext()
 
 	stKey := append([]byte{ownerPrefix}, subnetID...)
-	prefixLen := len(stKey)
 
 	rawOwner := storage.Get(ctx, stKey)
 	if rawOwner == nil {
 		panic("addNode: " + ErrSubNotExist)
 	}
 
-	owner := rawOwner.([]byte)
-	if !runtime.CheckWitness(owner) {
-		var hasAccess bool
-
 	stKey[0] = nodeAdminPrefix
 
-		iter := storage.Find(ctx, stKey, storage.KeysOnly)
+	owner := rawOwner.([]byte)
-		for iterator.Next(iter) {
-			key := iterator.Value(iter).([]byte)
-			if runtime.CheckWitness(key[prefixLen:]) {
-				hasAccess = true
-				break
-			}
-		}
 
-		if !hasAccess {
+	if !calledByOwnerOrAdmin(ctx, owner, stKey) {
 		panic("addNode: " + ErrAccessDenied)
 	}
-	}
 
 	stKey[0] = nodePrefix
 
@@ -275,32 +264,19 @@ func RemoveNode(subnetID []byte, node interop.PublicKey) {
 	ctx := storage.GetContext()
 
 	stKey := append([]byte{ownerPrefix}, subnetID...)
-	prefixLen := len(stKey)
 
 	rawOwner := storage.Get(ctx, stKey)
 	if rawOwner == nil {
 		panic("removeNode: " + ErrSubNotExist)
 	}
 
-	owner := rawOwner.([]byte)
-	if !runtime.CheckWitness(owner) {
-		var hasAccess bool
-
 	stKey[0] = nodeAdminPrefix
 
-		iter := storage.Find(ctx, stKey, storage.KeysOnly)
+	owner := rawOwner.([]byte)
-		for iterator.Next(iter) {
-			key := iterator.Value(iter).([]byte)
-			if runtime.CheckWitness(key[prefixLen:]) {
-				hasAccess = true
-				break
-			}
-		}
 
-		if !hasAccess {
+	if !calledByOwnerOrAdmin(ctx, owner, stKey) {
 		panic("removeNode: " + ErrAccessDenied)
 	}
-	}
 
 	stKey[0] = nodePrefix
 
@@ -413,28 +389,14 @@ func AddUser(subnetID []byte, groupID []byte, userID []byte) {
 		panic("addUser: " + ErrSubNotExist)
 	}
 
+	stKey[0] = clientAdminPrefix
 	stKey = append(stKey, groupID...)
-	prefixLen := len(stKey)
 
 	owner := rawOwner.([]byte)
-	if !runtime.CheckWitness(owner) {
-		var hasAccess bool
 
-		stKey[0] = clientAdminPrefix
+	if !calledByOwnerOrAdmin(ctx, owner, stKey) {
-
-		iter := storage.Find(ctx, stKey, storage.KeysOnly)
-		for iterator.Next(iter) {
-			key := iterator.Value(iter).([]byte)
-			if runtime.CheckWitness(key[prefixLen:]) {
-				hasAccess = true
-				break
-			}
-		}
-
-		if !hasAccess {
 		panic("addUser: " + ErrAccessDenied)
 	}
-	}
 
 	stKey[0] = userPrefix
 
@@ -445,6 +407,41 @@ func AddUser(subnetID []byte, groupID []byte, userID []byte) {
 	putKeyInList(ctx, userID, stKey)
 }
 
+// RemoveUser removes user from the specified subnetwork and group.
+// Must be called by the owner or the group's admin only.
+func RemoveUser(subnetID []byte, groupID []byte, userID []byte) {
+	// V2 format check
+	if len(userID) != userIDSize {
+		panic("addUser: " + ErrInvalidUser)
+	}
+
+	ctx := storage.GetContext()
+
+	stKey := append([]byte{ownerPrefix}, subnetID...)
+
+	rawOwner := storage.Get(ctx, stKey)
+	if rawOwner == nil {
+		panic("removeUser: " + ErrSubNotExist)
+	}
+
+	stKey[0] = clientAdminPrefix
+	stKey = append(stKey, groupID...)
+
+	owner := rawOwner.([]byte)
+
+	if !calledByOwnerOrAdmin(ctx, owner, stKey) {
+		panic("removeUser: " + ErrAccessDenied)
+	}
+
+	stKey[0] = userPrefix
+
+	if !keyInList(ctx, userID, stKey) {
+		panic("removeUser: " + ErrUserNotExist)
+	}
+
+	deleteKeyFromList(ctx, userID, stKey)
+}
+
 // Version returns version of the contract.
 func Version() int {
 	return common.Version
@@ -461,3 +458,21 @@ func putKeyInList(ctx storage.Context, keyToPut interop.PublicKey, prefix []byte
 func deleteKeyFromList(ctx storage.Context, keyToDelete interop.PublicKey, prefix []byte) {
 	storage.Delete(ctx, append(prefix, keyToDelete...))
 }
+
+func calledByOwnerOrAdmin(ctx storage.Context, owner []byte, adminPrefix []byte) bool {
+	if runtime.CheckWitness(owner) {
+		return true
+	}
+
+	prefixLen := len(adminPrefix)
+
+	iter := storage.Find(ctx, adminPrefix, storage.KeysOnly)
+	for iterator.Next(iter) {
+		key := iterator.Value(iter).([]byte)
+		if runtime.CheckWitness(key[prefixLen:]) {
+			return true
+		}
+	}
+
+	return false
+}

tests/subnet_test.go

@@ -258,6 +258,33 @@ func TestSubnet_AddUser(t *testing.T) {
 	cOwn.InvokeFail(t, method+errSeparator+"user has already been added", method, id, groupId, user)
 }
 
+func TestSubnet_RemoveUser(t *testing.T) {
+	e := newSubnetInvoker(t)
+
+	id, owner := createSubnet(t, e)
+
+	groupId := randomBytes(8)
+	user := randomBytes(27)
+
+	adm := e.NewAccount(t)
+	admPub, ok := vm.ParseSignatureContract(adm.Script())
+	require.True(t, ok)
+
+	const method = "removeUser"
+
+	cOwn := e.WithSigners(owner)
+	cOwn.InvokeFail(t, method+errSeparator+subnet.ErrSubNotExist, method, []byte{0, 0, 0, 0}, groupId, user)
+
+	cOwn.InvokeFail(t, method+errSeparator+subnet.ErrUserNotExist, method, id, groupId, user)
+	cOwn.Invoke(t, stackitem.Null{}, "addUser", id, groupId, user)
+	cOwn.Invoke(t, stackitem.Null{}, method, id, groupId, user)
+
+	cAdm := cOwn.WithSigners(adm)
+
+	cOwn.Invoke(t, stackitem.Null{}, "addClientAdmin", id, groupId, admPub)
+	cAdm.InvokeFail(t, method+errSeparator+subnet.ErrUserNotExist, method, id, groupId, user)
+}
+
 func createSubnet(t *testing.T, e *neotest.ContractInvoker) (id []byte, owner neotest.Signer) {
 	var (
 		ok  bool