neo-go/pkg/smartcontract/manifest/manifest.go
2021-02-05 19:10:15 +03:00

318 lines
8.4 KiB
Go

package manifest
import (
"encoding/json"
"errors"
"math"
"github.com/nspcc-dev/neo-go/pkg/io"
"github.com/nspcc-dev/neo-go/pkg/util"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
const (
// MaxManifestSize is a max length for a valid contract manifest.
MaxManifestSize = math.MaxUint16
// MethodInit is a name for default initialization method.
MethodInit = "_initialize"
// MethodDeploy is a name for default method called during contract deployment.
MethodDeploy = "_deploy"
// MethodVerify is a name for default verification method.
MethodVerify = "verify"
// MethodOnPayment is name of the method which is called when contract receives funds.
MethodOnPayment = "onPayment"
// NEP10StandardName represents the name of NEP10 smartcontract standard.
NEP10StandardName = "NEP-10"
// NEP17StandardName represents the name of NEP17 smartcontract standard.
NEP17StandardName = "NEP-17"
)
// ABI represents a contract application binary interface.
type ABI struct {
Methods []Method `json:"methods"`
Events []Event `json:"events"`
}
// Manifest represens contract metadata.
type Manifest struct {
// Name is a contract's name.
Name string `json:"name"`
// ABI is a contract's ABI.
ABI ABI `json:"abi"`
// Groups is a set of groups to which a contract belongs.
Groups []Group `json:"groups"`
Permissions []Permission `json:"permissions"`
// SupportedStandards is a list of standards supported by the contract.
SupportedStandards []string `json:"supportedstandards"`
// Trusts is a set of hashes to a which contract trusts.
Trusts WildUint160s `json:"trusts"`
// Extra is an implementation-defined user data.
Extra interface{} `json:"extra"`
}
// NewManifest returns new manifest with necessary fields initialized.
func NewManifest(name string) *Manifest {
m := &Manifest{
Name: name,
ABI: ABI{
Methods: []Method{},
Events: []Event{},
},
Groups: []Group{},
Permissions: []Permission{},
SupportedStandards: []string{},
}
m.Trusts.Restrict()
return m
}
// DefaultManifest returns default contract manifest.
func DefaultManifest(name string) *Manifest {
m := NewManifest(name)
m.Permissions = []Permission{*NewPermission(PermissionWildcard)}
return m
}
// GetMethod returns methods with the specified name.
func (a *ABI) GetMethod(name string, paramCount int) *Method {
for i := range a.Methods {
if a.Methods[i].Name == name && (paramCount == -1 || len(a.Methods[i].Parameters) == paramCount) {
return &a.Methods[i]
}
}
return nil
}
// GetEvent returns event with the specified name.
func (a *ABI) GetEvent(name string) *Event {
for i := range a.Events {
if a.Events[i].Name == name {
return &a.Events[i]
}
}
return nil
}
// CanCall returns true is current contract is allowed to call
// method of another contract with specified hash.
func (m *Manifest) CanCall(hash util.Uint160, toCall *Manifest, method string) bool {
for i := range m.Permissions {
if m.Permissions[i].IsAllowed(hash, toCall, method) {
return true
}
}
return false
}
// IsValid checks whether the hash given is correct wrt manifest's groups.
func (m *Manifest) IsValid(hash util.Uint160) bool {
for _, g := range m.Groups {
if !g.IsValid(hash) {
return false
}
}
return true
}
// EncodeBinary implements io.Serializable.
func (m *Manifest) EncodeBinary(w *io.BinWriter) {
data, err := json.Marshal(m)
if err != nil {
w.Err = err
return
}
w.WriteVarBytes(data)
}
// DecodeBinary implements io.Serializable.
func (m *Manifest) DecodeBinary(r *io.BinReader) {
data := r.ReadVarBytes(MaxManifestSize)
if r.Err != nil {
return
} else if err := json.Unmarshal(data, m); err != nil {
r.Err = err
}
}
// ToStackItem converts Manifest to stackitem.Item.
func (m *Manifest) ToStackItem() (stackitem.Item, error) {
groups := make([]stackitem.Item, len(m.Groups))
for i := range m.Groups {
groups[i] = m.Groups[i].ToStackItem()
}
supportedStandards := make([]stackitem.Item, len(m.SupportedStandards))
for i := range m.SupportedStandards {
supportedStandards[i] = stackitem.Make(m.SupportedStandards[i])
}
abi := m.ABI.ToStackItem()
permissions := make([]stackitem.Item, len(m.Permissions))
for i := range m.Permissions {
permissions[i] = m.Permissions[i].ToStackItem()
}
trusts := stackitem.Item(stackitem.Null{})
if !m.Trusts.IsWildcard() {
tItems := make([]stackitem.Item, len(m.Trusts.Value))
for i := range m.Trusts.Value {
tItems[i] = stackitem.NewByteArray(m.Trusts.Value[i].BytesBE())
}
trusts = stackitem.Make(tItems)
}
extra := stackitem.Make("null")
if m.Extra != nil {
e, err := json.Marshal(m.Extra)
if err != nil {
return nil, err
}
extra = stackitem.NewByteArray(e)
}
return stackitem.NewStruct([]stackitem.Item{
stackitem.Make(m.Name),
stackitem.Make(groups),
stackitem.Make(supportedStandards),
abi,
stackitem.Make(permissions),
trusts,
extra,
}), nil
}
// FromStackItem converts stackitem.Item to Manifest.
func (m *Manifest) FromStackItem(item stackitem.Item) error {
var err error
if item.Type() != stackitem.StructT {
return errors.New("invalid Manifest stackitem type")
}
str := item.Value().([]stackitem.Item)
if len(str) != 7 {
return errors.New("invalid stackitem length")
}
m.Name, err = stackitem.ToString(str[0])
if err != nil {
return err
}
if str[1].Type() != stackitem.ArrayT {
return errors.New("invalid Groups stackitem type")
}
groups := str[1].Value().([]stackitem.Item)
m.Groups = make([]Group, len(groups))
for i := range groups {
group := new(Group)
err := group.FromStackItem(groups[i])
if err != nil {
return err
}
m.Groups[i] = *group
}
if str[2].Type() != stackitem.ArrayT {
return errors.New("invalid SupportedStandards stackitem type")
}
supportedStandards := str[2].Value().([]stackitem.Item)
m.SupportedStandards = make([]string, len(supportedStandards))
for i := range supportedStandards {
m.SupportedStandards[i], err = stackitem.ToString(supportedStandards[i])
if err != nil {
return err
}
}
abi := new(ABI)
if err := abi.FromStackItem(str[3]); err != nil {
return err
}
m.ABI = *abi
if str[4].Type() != stackitem.ArrayT {
return errors.New("invalid Permissions stackitem type")
}
permissions := str[4].Value().([]stackitem.Item)
m.Permissions = make([]Permission, len(permissions))
for i := range permissions {
p := new(Permission)
if err := p.FromStackItem(permissions[i]); err != nil {
return err
}
m.Permissions[i] = *p
}
if _, ok := str[5].(stackitem.Null); ok {
m.Trusts.Restrict()
} else {
if str[5].Type() != stackitem.ArrayT {
return errors.New("invalid Trusts stackitem type")
}
trusts := str[5].Value().([]stackitem.Item)
m.Trusts = WildUint160s{Value: make([]util.Uint160, len(trusts))}
for i := range trusts {
bytes, err := trusts[i].TryBytes()
if err != nil {
return err
}
m.Trusts.Value[i], err = util.Uint160DecodeBytesBE(bytes)
if err != nil {
return err
}
}
}
extra, err := str[6].TryBytes()
if err != nil {
return err
}
if string(extra) == "null" {
return nil
}
return json.Unmarshal(extra, &m.Extra)
}
// ToStackItem converts ABI to stackitem.Item.
func (a *ABI) ToStackItem() stackitem.Item {
methods := make([]stackitem.Item, len(a.Methods))
for i := range a.Methods {
methods[i] = a.Methods[i].ToStackItem()
}
events := make([]stackitem.Item, len(a.Events))
for i := range a.Events {
events[i] = a.Events[i].ToStackItem()
}
return stackitem.NewStruct([]stackitem.Item{
stackitem.Make(methods),
stackitem.Make(events),
})
}
// FromStackItem converts stackitem.Item to ABI.
func (a *ABI) FromStackItem(item stackitem.Item) error {
if item.Type() != stackitem.StructT {
return errors.New("invalid ABI stackitem type")
}
str := item.Value().([]stackitem.Item)
if len(str) != 2 {
return errors.New("invalid ABI stackitem length")
}
if str[0].Type() != stackitem.ArrayT {
return errors.New("invalid Methods stackitem type")
}
methods := str[0].Value().([]stackitem.Item)
a.Methods = make([]Method, len(methods))
for i := range methods {
m := new(Method)
if err := m.FromStackItem(methods[i]); err != nil {
return err
}
a.Methods[i] = *m
}
if str[1].Type() != stackitem.ArrayT {
return errors.New("invalid Events stackitem type")
}
events := str[1].Value().([]stackitem.Item)
a.Events = make([]Event, len(events))
for i := range events {
e := new(Event)
if err := e.FromStackItem(events[i]); err != nil {
return err
}
a.Events[i] = *e
}
return nil
}