neo-go/pkg/core/native/policy.go
Roman Khimov aefb26255a dao: drop DAO interface
It's a remnant from the days when we had Simple and Cached DAO
implementations, now it makes zero sense.
2022-02-16 18:24:20 +03:00

351 lines
11 KiB
Go

package native
import (
"fmt"
"math/big"
"sort"
"sync"
"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/native/nativenames"
"github.com/nspcc-dev/neo-go/pkg/core/state"
"github.com/nspcc-dev/neo-go/pkg/core/transaction"
"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"
)
const (
policyContractID = -7
defaultExecFeeFactor = interop.DefaultBaseExecFee
defaultFeePerByte = 1000
defaultMaxVerificationGas = 1_50000000
// DefaultStoragePrice is the price to pay for 1 byte of storage.
DefaultStoragePrice = 100000
// maxExecFeeFactor is the maximum allowed execution fee factor.
maxExecFeeFactor = 100
// maxFeePerByte is the maximum allowed fee per byte value.
maxFeePerByte = 100_000_000
// maxStoragePrice is the maximum allowed price for a byte of storage.
maxStoragePrice = 10000000
// blockedAccountPrefix is a prefix used to store blocked account.
blockedAccountPrefix = 15
)
var (
// execFeeFactorKey is a key used to store execution fee factor.
execFeeFactorKey = []byte{18}
// feePerByteKey is a key used to store the minimum fee per byte for
// transaction.
feePerByteKey = []byte{10}
// storagePriceKey is a key used to store storage price.
storagePriceKey = []byte{19}
)
// Policy represents Policy native contract.
type Policy struct {
interop.ContractMD
NEO *NEO
lock sync.RWMutex
// isValid defies whether cached values were changed during the current
// consensus iteration. If false, these values will be updated after
// blockchain DAO persisting. If true, we can safely use cached values.
isValid bool
execFeeFactor uint32
feePerByte int64
maxVerificationGas int64
storagePrice uint32
blockedAccounts []util.Uint160
}
var _ interop.Contract = (*Policy)(nil)
// newPolicy returns Policy native contract.
func newPolicy() *Policy {
p := &Policy{ContractMD: *interop.NewContractMD(nativenames.Policy, policyContractID)}
defer p.UpdateHash()
desc := newDescriptor("getFeePerByte", smartcontract.IntegerType)
md := newMethodAndPrice(p.getFeePerByte, 1<<15, callflag.ReadStates)
p.AddMethod(md, desc)
desc = newDescriptor("isBlocked", smartcontract.BoolType,
manifest.NewParameter("account", smartcontract.Hash160Type))
md = newMethodAndPrice(p.isBlocked, 1<<15, callflag.ReadStates)
p.AddMethod(md, desc)
desc = newDescriptor("getExecFeeFactor", smartcontract.IntegerType)
md = newMethodAndPrice(p.getExecFeeFactor, 1<<15, callflag.ReadStates)
p.AddMethod(md, desc)
desc = newDescriptor("setExecFeeFactor", smartcontract.VoidType,
manifest.NewParameter("value", smartcontract.IntegerType))
md = newMethodAndPrice(p.setExecFeeFactor, 1<<15, callflag.States)
p.AddMethod(md, desc)
desc = newDescriptor("getStoragePrice", smartcontract.IntegerType)
md = newMethodAndPrice(p.getStoragePrice, 1<<15, callflag.ReadStates)
p.AddMethod(md, desc)
desc = newDescriptor("setStoragePrice", smartcontract.VoidType,
manifest.NewParameter("value", smartcontract.IntegerType))
md = newMethodAndPrice(p.setStoragePrice, 1<<15, callflag.States)
p.AddMethod(md, desc)
desc = newDescriptor("setFeePerByte", smartcontract.VoidType,
manifest.NewParameter("value", smartcontract.IntegerType))
md = newMethodAndPrice(p.setFeePerByte, 1<<15, callflag.States)
p.AddMethod(md, desc)
desc = newDescriptor("blockAccount", smartcontract.BoolType,
manifest.NewParameter("account", smartcontract.Hash160Type))
md = newMethodAndPrice(p.blockAccount, 1<<15, callflag.States)
p.AddMethod(md, desc)
desc = newDescriptor("unblockAccount", smartcontract.BoolType,
manifest.NewParameter("account", smartcontract.Hash160Type))
md = newMethodAndPrice(p.unblockAccount, 1<<15, callflag.States)
p.AddMethod(md, desc)
return p
}
// Metadata implements Contract interface.
func (p *Policy) Metadata() *interop.ContractMD {
return &p.ContractMD
}
// Initialize initializes Policy native contract and implements Contract interface.
func (p *Policy) Initialize(ic *interop.Context) error {
setIntWithKey(p.ID, ic.DAO, feePerByteKey, defaultFeePerByte)
setIntWithKey(p.ID, ic.DAO, execFeeFactorKey, defaultExecFeeFactor)
setIntWithKey(p.ID, ic.DAO, storagePriceKey, DefaultStoragePrice)
p.isValid = true
p.execFeeFactor = defaultExecFeeFactor
p.feePerByte = defaultFeePerByte
p.maxVerificationGas = defaultMaxVerificationGas
p.storagePrice = DefaultStoragePrice
p.blockedAccounts = make([]util.Uint160, 0)
return nil
}
// OnPersist implements Contract interface.
func (p *Policy) OnPersist(ic *interop.Context) error {
return nil
}
// PostPersist implements Contract interface.
func (p *Policy) PostPersist(ic *interop.Context) error {
p.lock.Lock()
defer p.lock.Unlock()
if p.isValid {
return nil
}
p.execFeeFactor = uint32(getIntWithKey(p.ID, ic.DAO, execFeeFactorKey))
p.feePerByte = getIntWithKey(p.ID, ic.DAO, feePerByteKey)
p.maxVerificationGas = defaultMaxVerificationGas
p.storagePrice = uint32(getIntWithKey(p.ID, ic.DAO, storagePriceKey))
p.blockedAccounts = make([]util.Uint160, 0)
siArr, err := ic.DAO.GetStorageItemsWithPrefix(p.ID, []byte{blockedAccountPrefix})
if err != nil {
return fmt.Errorf("failed to get blocked accounts from storage: %w", err)
}
for _, kv := range siArr {
hash, err := util.Uint160DecodeBytesBE([]byte(kv.Key))
if err != nil {
return fmt.Errorf("failed to decode blocked account hash: %w", err)
}
p.blockedAccounts = append(p.blockedAccounts, hash)
}
// blockedAccounts should be sorted by account BE bytes, but GetStorageItemsWithPrefix
// returns values sorted by key (which is account's BE bytes), so don't need to sort
// one more time.
p.isValid = true
return nil
}
// getFeePerByte is Policy contract method and returns required transaction's fee
// per byte.
func (p *Policy) getFeePerByte(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
return stackitem.NewBigInteger(big.NewInt(p.GetFeePerByteInternal(ic.DAO)))
}
// GetFeePerByteInternal returns required transaction's fee per byte.
func (p *Policy) GetFeePerByteInternal(dao *dao.Simple) int64 {
p.lock.RLock()
defer p.lock.RUnlock()
if p.isValid {
return p.feePerByte
}
return getIntWithKey(p.ID, dao, feePerByteKey)
}
// GetMaxVerificationGas returns maximum gas allowed to be burned during verificaion.
func (p *Policy) GetMaxVerificationGas(_ *dao.Simple) int64 {
if p.isValid {
return p.maxVerificationGas
}
return defaultMaxVerificationGas
}
func (p *Policy) getExecFeeFactor(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
return stackitem.NewBigInteger(big.NewInt(int64(p.GetExecFeeFactorInternal(ic.DAO))))
}
// GetExecFeeFactorInternal returns current execution fee factor.
func (p *Policy) GetExecFeeFactorInternal(d *dao.Simple) int64 {
p.lock.RLock()
defer p.lock.RUnlock()
if p.isValid {
return int64(p.execFeeFactor)
}
return getIntWithKey(p.ID, d, execFeeFactorKey)
}
func (p *Policy) setExecFeeFactor(ic *interop.Context, args []stackitem.Item) stackitem.Item {
value := toUint32(args[0])
if value <= 0 || maxExecFeeFactor < value {
panic(fmt.Errorf("ExecFeeFactor must be between 0 and %d", maxExecFeeFactor))
}
if !p.NEO.checkCommittee(ic) {
panic("invalid committee signature")
}
p.lock.Lock()
defer p.lock.Unlock()
setIntWithKey(p.ID, ic.DAO, execFeeFactorKey, int64(value))
p.isValid = false
return stackitem.Null{}
}
// isBlocked is Policy contract method and checks whether provided account is blocked.
func (p *Policy) isBlocked(ic *interop.Context, args []stackitem.Item) stackitem.Item {
hash := toUint160(args[0])
return stackitem.NewBool(p.IsBlockedInternal(ic.DAO, hash))
}
// IsBlockedInternal checks whether provided account is blocked.
func (p *Policy) IsBlockedInternal(dao *dao.Simple, hash util.Uint160) bool {
p.lock.RLock()
defer p.lock.RUnlock()
if p.isValid {
length := len(p.blockedAccounts)
i := sort.Search(length, func(i int) bool {
return !p.blockedAccounts[i].Less(hash)
})
if length != 0 && i != length && p.blockedAccounts[i].Equals(hash) {
return true
}
return false
}
key := append([]byte{blockedAccountPrefix}, hash.BytesBE()...)
return dao.GetStorageItem(p.ID, key) != nil
}
func (p *Policy) getStoragePrice(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
return stackitem.NewBigInteger(big.NewInt(p.GetStoragePriceInternal(ic.DAO)))
}
// GetStoragePriceInternal returns current execution fee factor.
func (p *Policy) GetStoragePriceInternal(d *dao.Simple) int64 {
p.lock.RLock()
defer p.lock.RUnlock()
if p.isValid {
return int64(p.storagePrice)
}
return getIntWithKey(p.ID, d, storagePriceKey)
}
func (p *Policy) setStoragePrice(ic *interop.Context, args []stackitem.Item) stackitem.Item {
value := toUint32(args[0])
if value <= 0 || maxStoragePrice < value {
panic(fmt.Errorf("StoragePrice must be between 0 and %d", maxStoragePrice))
}
if !p.NEO.checkCommittee(ic) {
panic("invalid committee signature")
}
p.lock.Lock()
defer p.lock.Unlock()
setIntWithKey(p.ID, ic.DAO, storagePriceKey, int64(value))
p.isValid = false
return stackitem.Null{}
}
// setFeePerByte is Policy contract method and sets transaction's fee per byte.
func (p *Policy) setFeePerByte(ic *interop.Context, args []stackitem.Item) stackitem.Item {
value := toBigInt(args[0]).Int64()
if value < 0 || value > maxFeePerByte {
panic(fmt.Errorf("FeePerByte shouldn't be negative or greater than %d", maxFeePerByte))
}
if !p.NEO.checkCommittee(ic) {
panic("invalid committee signature")
}
p.lock.Lock()
defer p.lock.Unlock()
setIntWithKey(p.ID, ic.DAO, feePerByteKey, value)
p.isValid = false
return stackitem.Null{}
}
// blockAccount is Policy contract method and adds given account hash to the list
// of blocked accounts.
func (p *Policy) blockAccount(ic *interop.Context, args []stackitem.Item) stackitem.Item {
if !p.NEO.checkCommittee(ic) {
panic("invalid committee signature")
}
hash := toUint160(args[0])
for i := range ic.Natives {
if ic.Natives[i].Metadata().Hash == hash {
panic("cannot block native contract")
}
}
if p.IsBlockedInternal(ic.DAO, hash) {
return stackitem.NewBool(false)
}
key := append([]byte{blockedAccountPrefix}, hash.BytesBE()...)
p.lock.Lock()
defer p.lock.Unlock()
ic.DAO.PutStorageItem(p.ID, key, state.StorageItem{})
p.isValid = false
return stackitem.NewBool(true)
}
// unblockAccount is Policy contract method and removes given account hash from
// the list of blocked accounts.
func (p *Policy) unblockAccount(ic *interop.Context, args []stackitem.Item) stackitem.Item {
if !p.NEO.checkCommittee(ic) {
panic("invalid committee signature")
}
hash := toUint160(args[0])
if !p.IsBlockedInternal(ic.DAO, hash) {
return stackitem.NewBool(false)
}
key := append([]byte{blockedAccountPrefix}, hash.BytesBE()...)
p.lock.Lock()
defer p.lock.Unlock()
ic.DAO.DeleteStorageItem(p.ID, key)
p.isValid = false
return stackitem.NewBool(true)
}
// CheckPolicy checks whether transaction conforms to current policy restrictions
// like not being signed by blocked account or not exceeding block-level system
// fee limit.
func (p *Policy) CheckPolicy(d *dao.Simple, tx *transaction.Transaction) error {
for _, signer := range tx.Signers {
if p.IsBlockedInternal(d, signer.Account) {
return fmt.Errorf("account %s is blocked", signer.Account.StringLE())
}
}
return nil
}