neo-go/pkg/core/native/name_service.go
Roman Khimov ac527650eb native: add Ledger contract, fix #1696
But don't change the way we process/store transactions and blocks. Effectively
it's just an interface for smart contracts that replaces old syscalls.

Transaction definition is moved temporarily to runtime package and Block
definition is removed (till we solve #1691 properly).
2021-02-04 13:12:11 +03:00

749 lines
20 KiB
Go

package native
import (
"encoding/binary"
"errors"
"math"
"math/big"
"net"
"regexp"
"sort"
"strings"
"unicode/utf8"
"github.com/nspcc-dev/neo-go/pkg/core/dao"
"github.com/nspcc-dev/neo-go/pkg/core/interop"
"github.com/nspcc-dev/neo-go/pkg/core/interop/runtime"
"github.com/nspcc-dev/neo-go/pkg/core/native/nativenames"
"github.com/nspcc-dev/neo-go/pkg/core/state"
"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
"github.com/nspcc-dev/neo-go/pkg/io"
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
"github.com/nspcc-dev/neo-go/pkg/util"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
// NameService represents native NameService contract.
type NameService struct {
nonfungible
NEO *NEO
}
type nameState struct {
state.NFTTokenState
// Expiration is token expiration height.
Expiration uint32
// HasAdmin is true if token has admin.
HasAdmin bool
// Admin is token admin.
Admin util.Uint160
}
// RecordType represents name record type.
type RecordType byte
// Pre-defined record types.
const (
RecordTypeA RecordType = 1
RecordTypeCNAME RecordType = 5
RecordTypeTXT RecordType = 16
RecordTypeAAAA RecordType = 28
)
const (
nameServiceID = -8
prefixRoots = 10
prefixDomainPrice = 22
prefixExpiration = 20
prefixRecord = 12
secondsInYear = 365 * 24 * 3600
// DefaultDomainPrice is the default price of register method.
DefaultDomainPrice = 10_00000000
// MinDomainNameLength is minimum domain length.
MinDomainNameLength = 3
// MaxDomainNameLength is maximum domain length.
MaxDomainNameLength = 255
)
var (
// Lookahead is not supported by Go, but it is simple `(?=.{3,255}$)`,
// so we check name length explicitly.
nameRegex = regexp.MustCompile("^([a-z0-9]{1,62}\\.)+[a-z][a-z0-9]{0,15}$")
ipv4Regex = regexp.MustCompile("^(2(5[0-5]|[0-4]\\d))|1?\\d{1,2}(\\.((2(5[0-5]|[0-4]\\d))|1?\\d{1,2})){3}$")
ipv6Regex = regexp.MustCompile("^([a-f0-9A-F]{1,4}:){7}[a-f0-9A-F]{1,4}$")
rootRegex = regexp.MustCompile("^[a-z][a-z0-9]{0,15}$")
)
// matchName checks if provided name is valid.
func matchName(name string) bool {
ln := len(name)
return MinDomainNameLength <= ln && ln <= MaxDomainNameLength &&
nameRegex.Match([]byte(name))
}
func newNameService() *NameService {
nf := newNonFungible(nativenames.NameService, nameServiceID, "NNS", 0)
nf.getTokenKey = func(tokenID []byte) []byte {
return append([]byte{prefixNFTToken}, hash.Hash160(tokenID).BytesBE()...)
}
nf.newTokenState = func() nftTokenState {
return new(nameState)
}
nf.onTransferred = func(tok nftTokenState) {
tok.(*nameState).HasAdmin = false
}
n := &NameService{nonfungible: *nf}
desc := newDescriptor("addRoot", smartcontract.VoidType,
manifest.NewParameter("root", smartcontract.StringType))
md := newMethodAndPrice(n.addRoot, 3000000, callflag.WriteStates)
n.AddMethod(md, desc)
desc = newDescriptor("setPrice", smartcontract.VoidType,
manifest.NewParameter("price", smartcontract.IntegerType))
md = newMethodAndPrice(n.setPrice, 3000000, callflag.WriteStates)
n.AddMethod(md, desc)
desc = newDescriptor("getPrice", smartcontract.IntegerType)
md = newMethodAndPrice(n.getPrice, 1000000, callflag.ReadStates)
n.AddMethod(md, desc)
desc = newDescriptor("isAvailable", smartcontract.BoolType,
manifest.NewParameter("name", smartcontract.StringType))
md = newMethodAndPrice(n.isAvailable, 1000000, callflag.ReadStates)
n.AddMethod(md, desc)
desc = newDescriptor("register", smartcontract.BoolType,
manifest.NewParameter("name", smartcontract.StringType),
manifest.NewParameter("owner", smartcontract.Hash160Type))
md = newMethodAndPrice(n.register, 1000000, callflag.WriteStates)
n.AddMethod(md, desc)
desc = newDescriptor("renew", smartcontract.IntegerType,
manifest.NewParameter("name", smartcontract.StringType))
md = newMethodAndPrice(n.renew, 0, callflag.WriteStates)
n.AddMethod(md, desc)
desc = newDescriptor("setAdmin", smartcontract.VoidType,
manifest.NewParameter("name", smartcontract.StringType),
manifest.NewParameter("admin", smartcontract.Hash160Type))
md = newMethodAndPrice(n.setAdmin, 3000000, callflag.WriteStates)
n.AddMethod(md, desc)
desc = newDescriptor("setRecord", smartcontract.VoidType,
manifest.NewParameter("name", smartcontract.StringType),
manifest.NewParameter("type", smartcontract.IntegerType),
manifest.NewParameter("data", smartcontract.StringType))
md = newMethodAndPrice(n.setRecord, 30000000, callflag.WriteStates)
n.AddMethod(md, desc)
desc = newDescriptor("getRecord", smartcontract.StringType,
manifest.NewParameter("name", smartcontract.StringType),
manifest.NewParameter("type", smartcontract.IntegerType))
md = newMethodAndPrice(n.getRecord, 1000000, callflag.ReadStates)
n.AddMethod(md, desc)
desc = newDescriptor("deleteRecord", smartcontract.VoidType,
manifest.NewParameter("name", smartcontract.StringType),
manifest.NewParameter("type", smartcontract.IntegerType))
md = newMethodAndPrice(n.deleteRecord, 1000000, callflag.WriteStates)
n.AddMethod(md, desc)
desc = newDescriptor("resolve", smartcontract.StringType,
manifest.NewParameter("name", smartcontract.StringType),
manifest.NewParameter("type", smartcontract.IntegerType))
md = newMethodAndPrice(n.resolve, 3000000, callflag.ReadStates)
n.AddMethod(md, desc)
return n
}
// Metadata implements interop.Contract interface.
func (n *NameService) Metadata() *interop.ContractMD {
return &n.ContractMD
}
// Initialize implements interop.Contract interface.
func (n *NameService) Initialize(ic *interop.Context) error {
si := &state.StorageItem{Value: bigint.ToBytes(big.NewInt(DefaultDomainPrice))}
if err := ic.DAO.PutStorageItem(n.ContractID, []byte{prefixDomainPrice}, si); err != nil {
return err
}
roots := stringList{}
return putSerializableToDAO(n.ContractID, ic.DAO, []byte{prefixRoots}, &roots)
}
// OnPersist implements interop.Contract interface.
func (n *NameService) OnPersist(ic *interop.Context) error {
now := uint32(ic.Block.Timestamp/1000 + 1)
keys := []string{}
ic.DAO.Seek(n.ContractID, []byte{prefixExpiration}, func(k, v []byte) {
if binary.BigEndian.Uint32(k) >= now {
return
}
// Removal is done separately because of `Seek` takes storage mutex.
keys = append(keys, string(k))
})
var keysToRemove [][]byte
key := []byte{prefixExpiration}
keyRecord := []byte{prefixRecord}
for i := range keys {
key[0] = prefixExpiration
key = append(key[:1], []byte(keys[i])...)
if err := ic.DAO.DeleteStorageItem(n.ContractID, key); err != nil {
return err
}
keysToRemove = keysToRemove[:0]
key[0] = prefixRecord
key = append(key[:1], keys[i][4:]...)
ic.DAO.Seek(n.ContractID, key, func(k, v []byte) {
keysToRemove = append(keysToRemove, k)
})
for i := range keysToRemove {
keyRecord = append(keyRecord[:0], key...)
keyRecord = append(keyRecord, keysToRemove[i]...)
err := ic.DAO.DeleteStorageItem(n.ContractID, keyRecord)
if err != nil {
return err
}
}
key[0] = prefixNFTToken
n.burnByKey(ic, key)
}
return nil
}
// PostPersist implements interop.Contract interface.
func (n *NameService) PostPersist(ic *interop.Context) error {
return nil
}
func (n *NameService) addRoot(ic *interop.Context, args []stackitem.Item) stackitem.Item {
root := toString(args[0])
if !rootRegex.Match([]byte(root)) {
panic("invalid root")
}
n.checkCommittee(ic)
roots, _ := n.getRootsInternal(ic.DAO)
if !roots.add(root) {
panic("name already exists")
}
err := putSerializableToDAO(n.ContractID, ic.DAO, []byte{prefixRoots}, &roots)
if err != nil {
panic(err)
}
return stackitem.Null{}
}
var maxPrice = big.NewInt(10000_00000000)
func (n *NameService) setPrice(ic *interop.Context, args []stackitem.Item) stackitem.Item {
price := toBigInt(args[0])
if price.Sign() <= 0 || price.Cmp(maxPrice) >= 0 {
panic("invalid price")
}
n.checkCommittee(ic)
si := &state.StorageItem{Value: bigint.ToBytes(price)}
err := ic.DAO.PutStorageItem(n.ContractID, []byte{prefixDomainPrice}, si)
if err != nil {
panic(err)
}
return stackitem.Null{}
}
func (n *NameService) getPrice(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
return stackitem.NewBigInteger(n.getPriceInternal(ic.DAO))
}
func (n *NameService) getPriceInternal(d dao.DAO) *big.Int {
si := d.GetStorageItem(n.ContractID, []byte{prefixDomainPrice})
return bigint.FromBytes(si.Value)
}
func (n *NameService) parseName(item stackitem.Item) (string, []string, []byte) {
name := toName(item)
names := strings.Split(name, ".")
if len(names) != 2 {
panic("invalid name")
}
return name, names, n.getTokenKey([]byte(name))
}
func (n *NameService) isAvailable(ic *interop.Context, args []stackitem.Item) stackitem.Item {
_, names, key := n.parseName(args[0])
if ic.DAO.GetStorageItem(n.ContractID, key) != nil {
return stackitem.NewBool(false)
}
roots, _ := n.getRootsInternal(ic.DAO)
_, ok := roots.index(names[1])
if !ok {
panic("domain is not registered")
}
return stackitem.NewBool(true)
}
func (n *NameService) getRootsInternal(d dao.DAO) (stringList, bool) {
var sl stringList
err := getSerializableFromDAO(n.ContractID, d, []byte{prefixRoots}, &sl)
if err != nil {
// Roots are being stored in `Initialize()` and thus must always be present.
panic(err)
}
return sl, true
}
func (n *NameService) register(ic *interop.Context, args []stackitem.Item) stackitem.Item {
name, names, key := n.parseName(args[0])
owner := toUint160(args[1])
if !n.checkWitness(ic, owner) {
panic("owner is not witnessed")
}
if ic.DAO.GetStorageItem(n.ContractID, key) != nil {
return stackitem.NewBool(false)
}
roots, _ := n.getRootsInternal(ic.DAO)
if _, ok := roots.index(names[1]); !ok {
panic("missing root")
}
if !ic.VM.AddGas(n.getPriceInternal(ic.DAO).Int64()) {
panic("insufficient gas")
}
token := &nameState{
NFTTokenState: state.NFTTokenState{
Owner: owner,
Name: name,
},
Expiration: uint32(ic.Block.Timestamp/1000 + secondsInYear),
}
n.mint(ic, token)
err := ic.DAO.PutStorageItem(n.ContractID,
makeExpirationKey(token.Expiration, token.ID()),
&state.StorageItem{Value: []byte{0}})
if err != nil {
panic(err)
}
return stackitem.NewBool(true)
}
func (n *NameService) renew(ic *interop.Context, args []stackitem.Item) stackitem.Item {
_, _, key := n.parseName(args[0])
if !ic.VM.AddGas(n.getPriceInternal(ic.DAO).Int64()) {
panic("insufficient gas")
}
token := new(nameState)
err := getSerializableFromDAO(n.ContractID, ic.DAO, key, token)
if err != nil {
panic(err)
}
keyExpiration := makeExpirationKey(token.Expiration, token.ID())
if err := ic.DAO.DeleteStorageItem(n.ContractID, keyExpiration); err != nil {
panic(err)
}
token.Expiration += secondsInYear
err = putSerializableToDAO(n.ContractID, ic.DAO, key, token)
if err != nil {
panic(err)
}
binary.BigEndian.PutUint32(key[1:], token.Expiration)
si := &state.StorageItem{Value: []byte{0}}
err = ic.DAO.PutStorageItem(n.ContractID, key, si)
if err != nil {
panic(err)
}
bi := new(big.Int).SetUint64(uint64(token.Expiration))
return stackitem.NewBigInteger(bi)
}
func (n *NameService) setAdmin(ic *interop.Context, args []stackitem.Item) stackitem.Item {
_, _, key := n.parseName(args[0])
var admin util.Uint160
_, isNull := args[1].(stackitem.Null)
if !isNull {
admin = toUint160(args[1])
if !n.checkWitness(ic, admin) {
panic("not witnessed by admin")
}
}
token := new(nameState)
err := getSerializableFromDAO(n.ContractID, ic.DAO, key, token)
if err != nil {
panic(err)
}
if !n.checkWitness(ic, token.Owner) {
panic("only owner can set admin")
}
token.HasAdmin = !isNull
token.Admin = admin
err = putSerializableToDAO(n.ContractID, ic.DAO, key, token)
if err != nil {
panic(err)
}
return stackitem.Null{}
}
func (n *NameService) checkWitness(ic *interop.Context, owner util.Uint160) bool {
ok, err := runtime.CheckHashedWitness(ic, owner)
if err != nil {
panic(err)
}
return ok
}
func (n *NameService) checkCommittee(ic *interop.Context) {
if !n.NEO.checkCommittee(ic) {
panic("not witnessed by committee")
}
}
func (n *NameService) checkAdmin(ic *interop.Context, token *nameState) bool {
if n.checkWitness(ic, token.Owner) {
return true
}
return token.HasAdmin && n.checkWitness(ic, token.Admin)
}
func (n *NameService) setRecord(ic *interop.Context, args []stackitem.Item) stackitem.Item {
name := toName(args[0])
rt := toRecordType(args[1])
data := toString(args[2])
n.checkName(rt, data)
domain := toDomain(name)
token, _, err := n.tokenState(ic.DAO, []byte(domain))
if err != nil {
panic(err)
}
if !n.checkAdmin(ic, token.(*nameState)) {
panic("not witnessed by admin")
}
key := makeRecordKey(domain, name, rt)
si := &state.StorageItem{Value: []byte(data)}
if err := ic.DAO.PutStorageItem(n.ContractID, key, si); err != nil {
panic(err)
}
return stackitem.Null{}
}
func (n *NameService) checkName(rt RecordType, name string) {
var valid bool
switch rt {
case RecordTypeA:
// We can't rely on `len(ip) == net.IPv4len` because
// IPv4 can be parsed to mapped representation.
valid = ipv4Regex.MatchString(name) &&
net.ParseIP(name) != nil
case RecordTypeCNAME:
valid = matchName(name)
case RecordTypeTXT:
valid = utf8.RuneCountInString(name) <= 255
case RecordTypeAAAA:
valid = ipv6Regex.MatchString(name) &&
net.ParseIP(name) != nil
}
if !valid {
panic("invalid name")
}
}
func (n *NameService) getRecord(ic *interop.Context, args []stackitem.Item) stackitem.Item {
name := toName(args[0])
domain := toDomain(name)
rt := toRecordType(args[1])
key := makeRecordKey(domain, name, rt)
si := ic.DAO.GetStorageItem(n.ContractID, key)
if si == nil {
return stackitem.Null{}
}
return stackitem.NewByteArray(si.Value)
}
func (n *NameService) deleteRecord(ic *interop.Context, args []stackitem.Item) stackitem.Item {
name := toName(args[0])
rt := toRecordType(args[1])
domain := toDomain(name)
key := n.getTokenKey([]byte(domain))
token := new(nameState)
err := getSerializableFromDAO(n.ContractID, ic.DAO, key, token)
if err != nil {
panic(err)
}
if !n.checkAdmin(ic, token) {
panic("not witnessed by admin")
}
key = makeRecordKey(domain, name, rt)
if err := ic.DAO.DeleteStorageItem(n.ContractID, key); err != nil {
panic(err)
}
return stackitem.Null{}
}
func (n *NameService) resolve(ic *interop.Context, args []stackitem.Item) stackitem.Item {
name := toString(args[0])
rt := toRecordType(args[1])
result, ok := n.resolveInternal(ic, name, rt, 2)
if !ok {
return stackitem.Null{}
}
return stackitem.NewByteArray([]byte(result))
}
func (n *NameService) resolveInternal(ic *interop.Context, name string, t RecordType, redirect int) (string, bool) {
if redirect < 0 {
panic("invalid redirect")
}
records := n.getRecordsInternal(ic.DAO, name)
if data, ok := records[t]; ok {
return data, true
}
data, ok := records[RecordTypeCNAME]
if !ok {
return "", false
}
return n.resolveInternal(ic, data, t, redirect-1)
}
func (n *NameService) getRecordsInternal(d dao.DAO, name string) map[RecordType]string {
domain := toDomain(name)
key := makeRecordKey(domain, name, 0)
key = key[:len(key)-1]
res := make(map[RecordType]string)
d.Seek(n.ContractID, key, func(k, v []byte) {
rt := RecordType(k[len(k)-1])
var si state.StorageItem
r := io.NewBinReaderFromBuf(v)
si.DecodeBinary(r)
if r.Err != nil {
panic(r.Err)
}
res[rt] = string(si.Value)
})
return res
}
func makeRecordKey(domain, name string, rt RecordType) []byte {
key := make([]byte, 1+util.Uint160Size+util.Uint160Size+1)
key[0] = prefixRecord
i := 1
i += copy(key[i:], hash.Hash160([]byte(domain)).BytesBE())
i += copy(key[i:], hash.Hash160([]byte(name)).BytesBE())
key[i] = byte(rt)
return key
}
func makeExpirationKey(expiration uint32, tokenID []byte) []byte {
key := make([]byte, 1+4+util.Uint160Size)
key[0] = prefixExpiration
binary.BigEndian.PutUint32(key[1:], expiration)
copy(key[5:], hash.Hash160(tokenID).BytesBE())
return key
}
// ToMap implements nftTokenState interface.
func (s *nameState) ToMap() *stackitem.Map {
m := s.NFTTokenState.ToMap()
m.Add(stackitem.NewByteArray([]byte("expiration")),
stackitem.NewBigInteger(new(big.Int).SetUint64(uint64(s.Expiration))))
return m
}
// EncodeBinary implements io.Serializable.
func (s *nameState) EncodeBinary(w *io.BinWriter) {
stackitem.EncodeBinaryStackItem(s.ToStackItem(), w)
}
// DecodeBinary implements io.Serializable.
func (s *nameState) DecodeBinary(r *io.BinReader) {
item := stackitem.DecodeBinaryStackItem(r)
if r.Err == nil {
s.FromStackItem(item)
}
}
// ToStackItem implements nftTokenState interface.
func (s *nameState) ToStackItem() stackitem.Item {
item := s.NFTTokenState.ToStackItem().(*stackitem.Struct)
exp := new(big.Int).SetUint64(uint64(s.Expiration))
item.Append(stackitem.NewBigInteger(exp))
if s.HasAdmin {
item.Append(stackitem.NewByteArray(s.Admin.BytesBE()))
} else {
item.Append(stackitem.Null{})
}
return item
}
// FromStackItem implements nftTokenState interface.
func (s *nameState) FromStackItem(item stackitem.Item) error {
err := s.NFTTokenState.FromStackItem(item)
if err != nil {
return err
}
elems := item.Value().([]stackitem.Item)
if len(elems) < 5 {
return errors.New("invalid stack item")
}
bi, err := elems[3].TryInteger()
if err != nil || !bi.IsUint64() {
return errors.New("invalid stack item")
}
_, isNull := elems[4].(stackitem.Null)
if !isNull {
bs, err := elems[4].TryBytes()
if err != nil {
return err
}
u, err := util.Uint160DecodeBytesBE(bs)
if err != nil {
return err
}
s.Admin = u
}
s.Expiration = uint32(bi.Uint64())
s.HasAdmin = !isNull
return nil
}
// Helpers
func domainFromString(name string) (string, bool) {
i := strings.LastIndexAny(name, ".")
if i < 0 {
return "", false
}
i = strings.LastIndexAny(name[:i], ".")
if i < 0 {
return name, true
}
return name[i+1:], true
}
func toDomain(name string) string {
domain, ok := domainFromString(name)
if !ok {
panic("invalid record")
}
return domain
}
func toRecordType(item stackitem.Item) RecordType {
bi, err := item.TryInteger()
if err != nil || !bi.IsInt64() {
panic("invalid record type")
}
val := bi.Uint64()
if val > math.MaxUint8 {
panic("invalid record type")
}
switch rt := RecordType(val); rt {
case RecordTypeA, RecordTypeCNAME, RecordTypeTXT, RecordTypeAAAA:
return rt
default:
panic("invalid record type")
}
}
func toName(item stackitem.Item) string {
name := toString(item)
if !matchName(name) {
panic("invalid name")
}
return name
}
type stringList []string
// ToStackItem converts sl to stack item.
func (sl stringList) ToStackItem() stackitem.Item {
arr := make([]stackitem.Item, len(sl))
for i := range sl {
arr[i] = stackitem.NewByteArray([]byte(sl[i]))
}
return stackitem.NewArray(arr)
}
// FromStackItem converts stack item to string list.
func (sl *stringList) FromStackItem(item stackitem.Item) error {
arr, ok := item.Value().([]stackitem.Item)
if !ok {
return errors.New("invalid stack item")
}
res := make([]string, len(arr))
for i := range res {
s, err := stackitem.ToString(arr[i])
if err != nil {
return err
}
res[i] = s
}
*sl = res
return nil
}
// EncodeBinary implements io.Serializable.
func (sl stringList) EncodeBinary(w *io.BinWriter) {
stackitem.EncodeBinaryStackItem(sl.ToStackItem(), w)
}
// DecodeBinary implements io.Serializable.
func (sl *stringList) DecodeBinary(r *io.BinReader) {
item := stackitem.DecodeBinaryStackItem(r)
if r.Err == nil {
sl.FromStackItem(item)
}
}
func (sl stringList) index(s string) (int, bool) {
index := sort.Search(len(sl), func(i int) bool {
return sl[i] >= s
})
return index, index < len(sl) && sl[index] == s
}
func (sl *stringList) remove(s string) bool {
index, has := sl.index(s)
if !has {
return false
}
copy((*sl)[index:], (*sl)[index+1:])
*sl = (*sl)[:len(*sl)-1]
return true
}
func (sl *stringList) add(s string) bool {
index, has := sl.index(s)
if has {
return false
}
*sl = append(*sl, "")
copy((*sl)[index+1:], (*sl)[index:])
(*sl)[index] = s
return true
}