neo-go/pkg/core/native/policy.go
Roman Khimov 9d2ef775cf storage: simplify (*MemCachedStore).Put/Delete interface
They never return errors, so their interface should reflect that. This allows
to remove quite a lot of useless and never tested code.

Notice that Get still does return an error. It can be made not to do that, but
usually we need to differentiate between successful/unsuccessful accesses
anyway, so this doesn't help much.
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.DAO) 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.DAO) 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.DAO) 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.DAO, 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.DAO) 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.DAO, 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
}