native: introduce attribute pricing

Port the neo-project/neo#2916.

Signed-off-by: Anna Shaleva <shaleva.ann@nspcc.ru>

pkg/compiler/native_test.go

@@ -123,6 +123,14 @@ func TestLedgerVMStates(t *testing.T) {
 	require.EqualValues(t, ledger.BreakState, vmstate.Break)
 }
 
+func TestPolicyAttributeType(t *testing.T) {
+	require.EqualValues(t, policy.HighPriority, transaction.HighPriority)
+	require.EqualValues(t, policy.OracleResponseT, transaction.OracleResponseT)
+	require.EqualValues(t, policy.NotValidBeforeT, transaction.NotValidBeforeT)
+	require.EqualValues(t, policy.ConflictsT, transaction.ConflictsT)
+	require.EqualValues(t, policy.NotaryAssistedT, transaction.NotaryAssistedT)
+}
+
 type nativeTestCase struct {
 	method string
 	params []string
@@ -179,6 +187,8 @@ func TestNativeHelpersCompile(t *testing.T) {
 		{"setFeePerByte", []string{"42"}},
 		{"setStoragePrice", []string{"42"}},
 		{"unblockAccount", []string{u160}},
+		{"getAttributeFee", []string{"1"}},
+		{"setAttributeFee", []string{"1", "123"}},
 	})
 	runNativeTestCases(t, cs.Ledger.ContractMD, "ledger", []nativeTestCase{
 		{"currentHash", nil},

pkg/core/blockchain.go

@@ -2485,7 +2485,7 @@ func (bc *Blockchain) verifyAndPoolTx(t *transaction.Transaction, pool *mempool.
 	if size > transaction.MaxTransactionSize {
 		return fmt.Errorf("%w: (%d > MaxTransactionSize %d)", ErrTxTooBig, size, transaction.MaxTransactionSize)
 	}
-	needNetworkFee := int64(size) * bc.FeePerByte()
+	needNetworkFee := int64(size)*bc.FeePerByte() + bc.CalculateAttributesFee(t)
 	if bc.P2PSigExtensionsEnabled() {
 		attrs := t.GetAttributes(transaction.NotaryAssistedT)
 		if len(attrs) != 0 {
@@ -2508,7 +2508,7 @@ func (bc *Blockchain) verifyAndPoolTx(t *transaction.Transaction, pool *mempool.
 			return err
 		}
 	}
-	err = bc.verifyTxWitnesses(t, nil, isPartialTx)
+	err = bc.verifyTxWitnesses(t, nil, isPartialTx, netFee)
 	if err != nil {
 		return err
 	}
@@ -2536,6 +2536,32 @@ func (bc *Blockchain) verifyAndPoolTx(t *transaction.Transaction, pool *mempool.
 	return nil
 }
 
+// CalculateAttributesFee returns network fee for all transaction attributes that should be
+// paid according to native Policy.
+func (bc *Blockchain) CalculateAttributesFee(tx *transaction.Transaction) int64 {
+	var (
+		feeCache map[transaction.AttrType]int64
+		feeSum   int64
+	)
+	for _, attr := range tx.Attributes {
+		if feeCache == nil {
+			feeCache = make(map[transaction.AttrType]int64)
+		}
+		base, ok := feeCache[attr.Type]
+		if !ok {
+			base = bc.contracts.Policy.GetAttributeFeeInternal(bc.dao, attr.Type)
+			feeCache[attr.Type] = base
+		}
+		switch attr.Type {
+		case transaction.ConflictsT:
+			feeSum += base * int64(len(tx.Signers))
+		default:
+			feeSum += base
+		}
+	}
+	return feeSum
+}
+
 func (bc *Blockchain) verifyTxAttributes(d *dao.Simple, tx *transaction.Transaction, isPartialTx bool) error {
 	for i := range tx.Attributes {
 		switch attrType := tx.Attributes[i].Type; attrType {
@@ -2885,17 +2911,24 @@ func (bc *Blockchain) verifyHashAgainstScript(hash util.Uint160, witness *transa
 // transaction. It can reorder them by ScriptHash, because that's required to
 // match a slice of script hashes from the Blockchain. Block parameter
 // is used for easy interop access and can be omitted for transactions that are
-// not yet added into any block.
+// not yet added into any block. verificationFee argument can be provided to
+// restrict the maximum amount of GAS allowed to spend on transaction
+// verification.
 // Golang implementation of VerifyWitnesses method in C# (https://github.com/neo-project/neo/blob/master/neo/SmartContract/Helper.cs#L87).
-func (bc *Blockchain) verifyTxWitnesses(t *transaction.Transaction, block *block.Block, isPartialTx bool) error {
+func (bc *Blockchain) verifyTxWitnesses(t *transaction.Transaction, block *block.Block, isPartialTx bool, verificationFee ...int64) error {
 	interopCtx := bc.newInteropContext(trigger.Verification, bc.dao, block, t)
-	gasLimit := t.NetworkFee - int64(t.Size())*bc.FeePerByte()
-	if bc.P2PSigExtensionsEnabled() {
-		attrs := t.GetAttributes(transaction.NotaryAssistedT)
-		if len(attrs) != 0 {
-			na := attrs[0].Value.(*transaction.NotaryAssisted)
-			gasLimit -= (int64(na.NKeys) + 1) * bc.contracts.Notary.GetNotaryServiceFeePerKey(bc.dao)
+	var gasLimit int64
+	if len(verificationFee) == 0 {
+		gasLimit = t.NetworkFee - int64(t.Size())*bc.FeePerByte() - bc.CalculateAttributesFee(t)
+		if bc.P2PSigExtensionsEnabled() {
+			attrs := t.GetAttributes(transaction.NotaryAssistedT)
+			if len(attrs) != 0 {
+				na := attrs[0].Value.(*transaction.NotaryAssisted)
+				gasLimit -= (int64(na.NKeys) + 1) * bc.contracts.Notary.GetNotaryServiceFeePerKey(bc.dao)
+			}
 		}
+	} else {
+		gasLimit = verificationFee[0]
 	}
 	for i := range t.Signers {
 		gasConsumed, err := bc.verifyHashAgainstScript(t.Signers[i].Account, &t.Scripts[i], interopCtx, gasLimit)

pkg/core/native/native_nep17.go

@@ -356,6 +356,18 @@ func toUint32(s stackitem.Item) uint32 {
 	return uint32(uint64Value)
 }
 
+func toUint8(s stackitem.Item) uint8 {
+	bigInt := toBigInt(s)
+	if !bigInt.IsUint64() {
+		panic("bigint is not an uint64")
+	}
+	uint64Value := bigInt.Uint64()
+	if uint64Value > math.MaxUint8 {
+		panic("bigint does not fit into uint8")
+	}
+	return uint8(uint64Value)
+}
+
 func toInt64(s stackitem.Item) int64 {
 	bigInt := toBigInt(s)
 	if !bigInt.IsInt64() {

pkg/core/native/native_test/policy_test.go

@@ -7,8 +7,14 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/native"
 	"github.com/nspcc-dev/neo-go/pkg/core/native/nativenames"
+	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
+	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/neotest"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
 	"github.com/nspcc-dev/neo-go/pkg/util"
+	"github.com/nspcc-dev/neo-go/pkg/vm/emit"
+	"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
+	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
 )
 
 func newPolicyClient(t *testing.T) *neotest.ContractInvoker {
@@ -39,6 +45,67 @@ func TestPolicy_StoragePriceCache(t *testing.T) {
 	testGetSetCache(t, newPolicyClient(t), "StoragePrice", native.DefaultStoragePrice)
 }
 
+func TestPolicy_AttributeFee(t *testing.T) {
+	c := newPolicyClient(t)
+	getName := "getAttributeFee"
+	setName := "setAttributeFee"
+
+	randomInvoker := c.WithSigners(c.NewAccount(t))
+	committeeInvoker := c.WithSigners(c.Committee)
+
+	t.Run("set, not signed by committee", func(t *testing.T) {
+		randomInvoker.InvokeFail(t, "invalid committee signature", setName, byte(transaction.ConflictsT), 123)
+	})
+	t.Run("get, unknown attribute", func(t *testing.T) {
+		randomInvoker.InvokeFail(t, "invalid attribute type: 84", getName, byte(0x54))
+	})
+	t.Run("get, default value", func(t *testing.T) {
+		randomInvoker.Invoke(t, 0, getName, byte(transaction.ConflictsT))
+	})
+	t.Run("set, too large value", func(t *testing.T) {
+		committeeInvoker.InvokeFail(t, "out of range", setName, byte(transaction.ConflictsT), 10_0000_0001)
+	})
+	t.Run("set, unknown attribute", func(t *testing.T) {
+		committeeInvoker.InvokeFail(t, "invalid attribute type: 84", setName, 0x54, 5)
+	})
+	t.Run("set, success", func(t *testing.T) {
+		// Set and get in the same block.
+		txSet := committeeInvoker.PrepareInvoke(t, setName, byte(transaction.ConflictsT), 1)
+		txGet := randomInvoker.PrepareInvoke(t, getName, byte(transaction.ConflictsT))
+		c.AddNewBlock(t, txSet, txGet)
+		c.CheckHalt(t, txSet.Hash(), stackitem.Null{})
+		c.CheckHalt(t, txGet.Hash(), stackitem.Make(1))
+		// Get in the next block.
+		randomInvoker.Invoke(t, 1, getName, byte(transaction.ConflictsT))
+	})
+}
+
+func TestPolicy_AttributeFeeCache(t *testing.T) {
+	c := newPolicyClient(t)
+	getName := "getAttributeFee"
+	setName := "setAttributeFee"
+
+	committeeInvoker := c.WithSigners(c.Committee)
+
+	// Change fee, abort the transaction and check that contract cache wasn't persisted
+	// for FAULTed tx at the same block.
+	w := io.NewBufBinWriter()
+	emit.AppCall(w.BinWriter, committeeInvoker.Hash, setName, callflag.All, byte(transaction.ConflictsT), 5)
+	emit.Opcodes(w.BinWriter, opcode.ABORT)
+	tx1 := committeeInvoker.PrepareInvocation(t, w.Bytes(), committeeInvoker.Signers)
+	tx2 := committeeInvoker.PrepareInvoke(t, getName, byte(transaction.ConflictsT))
+	committeeInvoker.AddNewBlock(t, tx1, tx2)
+	committeeInvoker.CheckFault(t, tx1.Hash(), "ABORT")
+	committeeInvoker.CheckHalt(t, tx2.Hash(), stackitem.Make(0))
+
+	// Change fee and check that change is available for the next tx.
+	tx1 = committeeInvoker.PrepareInvoke(t, setName, byte(transaction.ConflictsT), 5)
+	tx2 = committeeInvoker.PrepareInvoke(t, getName, byte(transaction.ConflictsT))
+	committeeInvoker.AddNewBlock(t, tx1, tx2)
+	committeeInvoker.CheckHalt(t, tx1.Hash())
+	committeeInvoker.CheckHalt(t, tx2.Hash(), stackitem.Make(5))
+}
+
 func TestPolicy_BlockedAccounts(t *testing.T) {
 	c := newPolicyClient(t)
 	e := c.Executor

pkg/core/native/policy.go

@@ -1,6 +1,7 @@
 package native
 
 import (
+	"encoding/hex"
 	"fmt"
 	"math/big"
 	"sort"
@@ -11,6 +12,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
+	"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
 	"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"
@@ -24,6 +26,8 @@ const (
 	defaultExecFeeFactor      = interop.DefaultBaseExecFee
 	defaultFeePerByte         = 1000
 	defaultMaxVerificationGas = 1_50000000
+	// defaultAttributeFee is a default fee for a transaction attribute those price wasn't set yet.
+	defaultAttributeFee = 0
 	// DefaultStoragePrice is the price to pay for 1 byte of storage.
 	DefaultStoragePrice = 100000
 
@@ -33,9 +37,13 @@ const (
 	maxFeePerByte = 100_000_000
 	// maxStoragePrice is the maximum allowed price for a byte of storage.
 	maxStoragePrice = 10000000
+	// maxAttributeFee is the maximum allowed value for a transaction attribute fee.
+	maxAttributeFee = 10_00000000
 
 	// blockedAccountPrefix is a prefix used to store blocked account.
 	blockedAccountPrefix = 15
+	// attributeFeePrefix is a prefix used to store attribute fee.
+	attributeFeePrefix = 20
 )
 
 var (
@@ -59,6 +67,7 @@ type PolicyCache struct {
 	feePerByte         int64
 	maxVerificationGas int64
 	storagePrice       uint32
+	attributeFee       map[transaction.AttrType]uint32
 	blockedAccounts    []util.Uint160
 }
 
@@ -76,6 +85,10 @@ func (c *PolicyCache) Copy() dao.NativeContractCache {
 
 func copyPolicyCache(src, dst *PolicyCache) {
 	*dst = *src
+	dst.attributeFee = make(map[transaction.AttrType]uint32, len(src.attributeFee))
+	for t, v := range src.attributeFee {
+		dst.attributeFee[t] = v
+	}
 	dst.blockedAccounts = make([]util.Uint160, len(src.blockedAccounts))
 	copy(dst.blockedAccounts, src.blockedAccounts)
 }
@@ -112,6 +125,17 @@ func newPolicy() *Policy {
 	md = newMethodAndPrice(p.setStoragePrice, 1<<15, callflag.States)
 	p.AddMethod(md, desc)
 
+	desc = newDescriptor("getAttributeFee", smartcontract.IntegerType,
+		manifest.NewParameter("attributeType", smartcontract.IntegerType))
+	md = newMethodAndPrice(p.getAttributeFee, 1<<15, callflag.ReadStates)
+	p.AddMethod(md, desc)
+
+	desc = newDescriptor("setAttributeFee", smartcontract.VoidType,
+		manifest.NewParameter("attributeType", smartcontract.IntegerType),
+		manifest.NewParameter("value", smartcontract.IntegerType))
+	md = newMethodAndPrice(p.setAttributeFee, 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)
@@ -146,6 +170,7 @@ func (p *Policy) Initialize(ic *interop.Context) error {
 		feePerByte:         defaultFeePerByte,
 		maxVerificationGas: defaultMaxVerificationGas,
 		storagePrice:       DefaultStoragePrice,
+		attributeFee:       map[transaction.AttrType]uint32{},
 		blockedAccounts:    make([]util.Uint160, 0),
 	}
 	ic.DAO.SetCache(p.ID, cache)
@@ -183,6 +208,25 @@ func (p *Policy) fillCacheFromDAO(cache *PolicyCache, d *dao.Simple) error {
 	if fErr != nil {
 		return fmt.Errorf("failed to initialize blocked accounts: %w", fErr)
 	}
+
+	cache.attributeFee = make(map[transaction.AttrType]uint32)
+	d.Seek(p.ID, storage.SeekRange{Prefix: []byte{attributeFeePrefix}}, func(k, v []byte) bool {
+		if len(k) != 1 {
+			fErr = fmt.Errorf("unexpected attribute type len %d (%s)", len(k), hex.EncodeToString(k))
+			return false
+		}
+		t := transaction.AttrType(k[0])
+		value := bigint.FromBytes(v)
+		if value == nil {
+			fErr = fmt.Errorf("unexpected attribute value format: key=%s, value=%s", hex.EncodeToString(k), hex.EncodeToString(v))
+			return false
+		}
+		cache.attributeFee[t] = uint32(value.Int64())
+		return true
+	})
+	if fErr != nil {
+		return fmt.Errorf("failed to initialize attribute fees: %w", fErr)
+	}
 	return nil
 }
 
@@ -290,6 +334,43 @@ func (p *Policy) setStoragePrice(ic *interop.Context, args []stackitem.Item) sta
 	return stackitem.Null{}
 }
 
+func (p *Policy) getAttributeFee(ic *interop.Context, args []stackitem.Item) stackitem.Item {
+	t := transaction.AttrType(toUint8(args[0]))
+	if !transaction.IsValidAttrType(ic.Chain.GetConfig().ReservedAttributes, t) {
+		panic(fmt.Errorf("invalid attribute type: %d", t))
+	}
+	return stackitem.NewBigInteger(big.NewInt(p.GetAttributeFeeInternal(ic.DAO, t)))
+}
+
+// GetAttributeFeeInternal returns required transaction's attribute fee.
+func (p *Policy) GetAttributeFeeInternal(d *dao.Simple, t transaction.AttrType) int64 {
+	cache := d.GetROCache(p.ID).(*PolicyCache)
+	v, ok := cache.attributeFee[t]
+	if !ok {
+		// We may safely omit this part, but let it be here in case if defaultAttributeFee value is changed.
+		v = defaultAttributeFee
+	}
+	return int64(v)
+}
+
+func (p *Policy) setAttributeFee(ic *interop.Context, args []stackitem.Item) stackitem.Item {
+	t := transaction.AttrType(toUint8(args[0]))
+	value := toUint32(args[1])
+	if !transaction.IsValidAttrType(ic.Chain.GetConfig().ReservedAttributes, t) {
+		panic(fmt.Errorf("invalid attribute type: %d", t))
+	}
+	if value > maxAttributeFee {
+		panic(fmt.Errorf("attribute value is out of range: %d", value))
+	}
+	if !p.NEO.checkCommittee(ic) {
+		panic("invalid committee signature")
+	}
+	setIntWithKey(p.ID, ic.DAO, []byte{attributeFeePrefix, byte(t)}, int64(value))
+	cache := ic.DAO.GetRWCache(p.ID).(*PolicyCache)
+	cache.attributeFee[t] = value
+	return stackitem.Null{}
+}
+
 // setFeePerByte is a Policy contract method that sets transaction's fee per byte.
 func (p *Policy) setFeePerByte(ic *interop.Context, args []stackitem.Item) stackitem.Item {
 	value := toBigInt(args[0]).Int64()

pkg/core/transaction/attrtype.go

@@ -21,6 +21,15 @@ const (
 	NotaryAssistedT AttrType = 0x22 // NotaryAssisted
 )
 
+// attrTypes contains a set of valid attribute types (does not include reserved attributes).
+var attrTypes = map[AttrType]struct{}{
+	HighPriority:    {},
+	OracleResponseT: {},
+	NotValidBeforeT: {},
+	ConflictsT:      {},
+	NotaryAssistedT: {},
+}
+
 func (a AttrType) allowMultiple() bool {
 	switch a {
 	case ConflictsT:
@@ -29,3 +38,11 @@ func (a AttrType) allowMultiple() bool {
 		return false
 	}
 }
+
+// IsValidAttrType returns whether the provided attribute type is valid.
+func IsValidAttrType(reservedAttributesEnabled bool, attrType AttrType) bool {
+	if _, ok := attrTypes[attrType]; ok {
+		return true
+	}
+	return reservedAttributesEnabled && ReservedLowerBound <= attrType && attrType <= ReservedUpperBound
+}