frostfs-node/pkg/morph/client/notary.go
Evgenii Stratonikov 050a4bb2b0 [#1115] *: link TODOs to corresponding issues
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
2022-02-11 12:58:59 +03:00

888 lines
24 KiB
Go

package client
import (
"encoding/binary"
"errors"
"fmt"
"strings"
"github.com/nspcc-dev/neo-go/pkg/core/native/nativenames"
"github.com/nspcc-dev/neo-go/pkg/core/native/noderoles"
"github.com/nspcc-dev/neo-go/pkg/core/transaction"
"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
"github.com/nspcc-dev/neo-go/pkg/encoding/fixedn"
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
sc "github.com/nspcc-dev/neo-go/pkg/smartcontract"
"github.com/nspcc-dev/neo-go/pkg/util"
"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
"github.com/nspcc-dev/neo-go/pkg/wallet"
"github.com/nspcc-dev/neofs-node/pkg/util/rand"
"go.uber.org/zap"
)
type (
notary struct {
txValidTime uint32 // minimum amount of blocks when mainTx will be valid
roundTime uint32 // extra amount of blocks to synchronize sidechain height diff of inner ring nodes
fallbackTime uint32 // mainTx's ValidUntilBlock - fallbackTime + 1 is when fallbackTx is sent
alphabetSource AlphabetKeys // source of alphabet node keys to prepare witness
notary util.Uint160
proxy util.Uint160
}
notaryCfg struct {
proxy util.Uint160
txValidTime, roundTime, fallbackTime uint32
alphabetSource AlphabetKeys
}
AlphabetKeys func() (keys.PublicKeys, error)
NotaryOption func(*notaryCfg)
)
const (
defaultNotaryValidTime = 50
defaultNotaryRoundTime = 100
defaultNotaryFallbackTime = 40
notaryBalanceOfMethod = "balanceOf"
notaryExpirationOfMethod = "expirationOf"
setDesignateMethod = "designateAsRole"
notaryBalanceErrMsg = "can't fetch notary balance"
notaryNotEnabledPanicMsg = "notary support was not enabled on this client"
)
var errUnexpectedItems = errors.New("invalid number of NEO VM arguments on stack")
func defaultNotaryConfig(c *Client) *notaryCfg {
return &notaryCfg{
txValidTime: defaultNotaryValidTime,
roundTime: defaultNotaryRoundTime,
fallbackTime: defaultNotaryFallbackTime,
alphabetSource: c.Committee,
}
}
// EnableNotarySupport creates notary structure in client that provides
// ability for client to get alphabet keys from committee or provided source
// and use proxy contract script hash to create tx for notary contract.
func (c *Client) EnableNotarySupport(opts ...NotaryOption) error {
cfg := defaultNotaryConfig(c)
for _, opt := range opts {
opt(cfg)
}
if cfg.proxy.Equals(util.Uint160{}) {
var err error
cfg.proxy, err = c.NNSContractAddress(NNSProxyContractName)
if err != nil {
return fmt.Errorf("get proxy contract addess from NNS: %w", err)
}
}
notaryCfg := &notary{
proxy: cfg.proxy,
txValidTime: cfg.txValidTime,
roundTime: cfg.roundTime,
fallbackTime: cfg.fallbackTime,
alphabetSource: cfg.alphabetSource,
}
var err error
getNotaryHashFunc := func(c *Client) error {
notaryCfg.notary, err = c.client.GetNativeContractHash(nativenames.Notary)
if err != nil {
return fmt.Errorf("can't get notary contract script hash: %w", err)
}
return nil
}
if c.multiClient == nil {
// single client case
err = getNotaryHashFunc(c)
if err != nil {
return err
}
c.notary = notaryCfg
return nil
}
// multi client case
if err = c.iterateClients(getNotaryHashFunc); err != nil {
return err
}
c.clientsMtx.Lock()
c.sharedNotary = notaryCfg
// update client cache
for _, cached := range c.clients {
cached.notary = c.sharedNotary
}
c.clientsMtx.Unlock()
return nil
}
// ProbeNotary checks if native `Notary` contract is presented on chain.
func (c *Client) ProbeNotary() (res bool) {
if c.multiClient != nil {
_ = c.multiClient.iterateClients(func(c *Client) error {
res = c.ProbeNotary()
return nil
})
return
}
_, err := c.client.GetNativeContractHash(nativenames.Notary)
return err == nil
}
// DepositNotary calls notary deposit method. Deposit is required to operate
// with notary contract. It used by notary contract in to produce fallback tx
// if main tx failed to create. Deposit isn't last forever, so it should
// be called periodically. Notary support should be enabled in client to
// use this function.
//
// This function must be invoked with notary enabled otherwise it throws panic.
func (c *Client) DepositNotary(amount fixedn.Fixed8, delta uint32) (res util.Uint256, err error) {
if c.multiClient != nil {
return res, c.multiClient.iterateClients(func(c *Client) error {
res, err = c.DepositNotary(amount, delta)
return err
})
}
if c.notary == nil {
panic(notaryNotEnabledPanicMsg)
}
bc, err := c.client.GetBlockCount()
if err != nil {
return util.Uint256{}, fmt.Errorf("can't get blockchain height: %w", err)
}
currentTill, err := c.depositExpirationOf()
if err != nil {
return util.Uint256{}, fmt.Errorf("can't get previous expiration value: %w", err)
}
till := int64(bc + delta)
if till < currentTill {
till = currentTill
}
gas, err := c.client.GetNativeContractHash(nativenames.Gas)
if err != nil {
return util.Uint256{}, fmt.Errorf("can't get GAS script hash: %w", err)
}
txHash, err := c.client.TransferNEP17(
c.acc,
c.notary.notary,
gas,
int64(amount),
0,
[]interface{}{c.acc.PrivateKey().GetScriptHash(), till},
nil,
)
if err != nil {
return util.Uint256{}, fmt.Errorf("can't make notary deposit: %w", err)
}
c.logger.Debug("notary deposit invoke",
zap.Int64("amount", int64(amount)),
zap.Int64("expire_at", till),
zap.Stringer("tx_hash", txHash.Reverse()))
return txHash, nil
}
// GetNotaryDeposit returns deposit of client's account in notary contract.
// Notary support should be enabled in client to use this function.
//
// This function must be invoked with notary enabled otherwise it throws panic.
func (c *Client) GetNotaryDeposit() (res int64, err error) {
if c.multiClient != nil {
return res, c.multiClient.iterateClients(func(c *Client) error {
res, err = c.GetNotaryDeposit()
return err
})
}
if c.notary == nil {
panic(notaryNotEnabledPanicMsg)
}
sh := c.acc.PrivateKey().PublicKey().GetScriptHash()
items, err := c.TestInvoke(c.notary.notary, notaryBalanceOfMethod, sh)
if err != nil {
return 0, fmt.Errorf("%v: %w", notaryBalanceErrMsg, err)
}
if len(items) != 1 {
return 0, wrapNeoFSError(fmt.Errorf("%v: %w", notaryBalanceErrMsg, errUnexpectedItems))
}
bigIntDeposit, err := items[0].TryInteger()
if err != nil {
return 0, wrapNeoFSError(fmt.Errorf("%v: %w", notaryBalanceErrMsg, err))
}
return bigIntDeposit.Int64(), nil
}
// UpdateNotaryListPrm groups parameters of UpdateNotaryList operation.
type UpdateNotaryListPrm struct {
list keys.PublicKeys
hash util.Uint256
}
// SetList sets list of the new notary role keys.
func (u *UpdateNotaryListPrm) SetList(list keys.PublicKeys) {
u.list = list
}
// SetHash sets hash of the transaction that led to the update
// of the notary role in the designate contract.
func (u *UpdateNotaryListPrm) SetHash(hash util.Uint256) {
u.hash = hash
}
// UpdateNotaryList updates list of notary nodes in designate contract. Requires
// committee multi signature.
//
// This function must be invoked with notary enabled otherwise it throws panic.
func (c *Client) UpdateNotaryList(prm UpdateNotaryListPrm) error {
if c.multiClient != nil {
return c.multiClient.iterateClients(func(c *Client) error {
return c.UpdateNotaryList(prm)
})
}
if c.notary == nil {
panic(notaryNotEnabledPanicMsg)
}
nonce, vub, err := c.CalculateNonceAndVUB(prm.hash)
if err != nil {
return fmt.Errorf("could not calculate nonce and `valicUntilBlock` values: %w", err)
}
return c.notaryInvokeAsCommittee(
setDesignateMethod,
nonce,
vub,
noderoles.P2PNotary,
prm.list,
)
}
// UpdateAlphabetListPrm groups parameters of UpdateNeoFSAlphabetList operation.
type UpdateAlphabetListPrm struct {
list keys.PublicKeys
hash util.Uint256
}
// SetList sets list of the new alphabet role keys.
func (u *UpdateAlphabetListPrm) SetList(list keys.PublicKeys) {
u.list = list
}
// SetHash sets hash of the transaction that led to the update
// of the alphabet role in the designate contract.
func (u *UpdateAlphabetListPrm) SetHash(hash util.Uint256) {
u.hash = hash
}
// UpdateNeoFSAlphabetList updates list of alphabet nodes in designate contract.
// As for side chain list should contain all inner ring nodes.
// Requires committee multi signature.
//
// This function must be invoked with notary enabled otherwise it throws panic.
func (c *Client) UpdateNeoFSAlphabetList(prm UpdateAlphabetListPrm) error {
if c.multiClient != nil {
return c.multiClient.iterateClients(func(c *Client) error {
return c.UpdateNeoFSAlphabetList(prm)
})
}
if c.notary == nil {
panic(notaryNotEnabledPanicMsg)
}
nonce, vub, err := c.CalculateNonceAndVUB(prm.hash)
if err != nil {
return fmt.Errorf("could not calculate nonce and `valicUntilBlock` values: %w", err)
}
return c.notaryInvokeAsCommittee(
setDesignateMethod,
nonce,
vub,
noderoles.NeoFSAlphabet,
prm.list,
)
}
// NotaryInvoke invokes contract method by sending tx to notary contract in
// blockchain. Fallback tx is a `RET`. If Notary support is not enabled
// it fallbacks to a simple `Invoke()`.
//
// `nonce` and `vub` are used only if notary is enabled.
func (c *Client) NotaryInvoke(contract util.Uint160, fee fixedn.Fixed8, nonce uint32, vub *uint32, method string, args ...interface{}) error {
if c.multiClient != nil {
return c.multiClient.iterateClients(func(c *Client) error {
return c.NotaryInvoke(contract, fee, nonce, vub, method, args...)
})
}
if c.notary == nil {
return c.Invoke(contract, fee, method, args...)
}
return c.notaryInvoke(false, true, contract, nonce, vub, method, args...)
}
// NotaryInvokeNotAlpha does the same as NotaryInvoke but does not use client's
// private key in Invocation script. It means that main TX of notary request is
// not expected to be signed by the current node.
//
// Considered to be used by non-IR nodes.
func (c *Client) NotaryInvokeNotAlpha(contract util.Uint160, fee fixedn.Fixed8, method string, args ...interface{}) error {
if c.multiClient != nil {
return c.multiClient.iterateClients(func(c *Client) error {
return c.NotaryInvokeNotAlpha(contract, fee, method, args...)
})
}
if c.notary == nil {
return c.Invoke(contract, fee, method, args...)
}
return c.notaryInvoke(false, false, contract, rand.Uint32(), nil, method, args...)
}
// NotarySignAndInvokeTX signs and sends notary request that was received from
// Notary service.
// NOTE: does not fallback to simple `Invoke()`. Expected to be used only for
// TXs retrieved from the received notary requests.
func (c *Client) NotarySignAndInvokeTX(mainTx *transaction.Transaction) error {
if c.multiClient != nil {
return c.multiClient.iterateClients(func(c *Client) error {
return c.NotarySignAndInvokeTX(mainTx)
})
}
alphabetList, err := c.notary.alphabetSource()
if err != nil {
return fmt.Errorf("could not fetch current alphabet keys: %w", err)
}
multiaddrAccount, err := c.notaryMultisigAccount(alphabetList, false, true)
if err != nil {
return err
}
// mainTX is expected to be pre-validated: second witness must exist and be empty
mainTx.Scripts[1].VerificationScript = multiaddrAccount.GetVerificationScript()
mainTx.Scripts[1].InvocationScript = append(
[]byte{byte(opcode.PUSHDATA1), 64},
multiaddrAccount.PrivateKey().SignHashable(uint32(c.client.GetNetwork()), mainTx)...,
)
resp, err := c.client.SignAndPushP2PNotaryRequest(mainTx,
[]byte{byte(opcode.RET)},
-1,
0,
c.notary.fallbackTime,
c.acc)
if err != nil && !alreadyOnChainError(err) {
return err
}
c.logger.Debug("notary request with prepared main TX invoked",
zap.Uint32("fallback_valid_for", c.notary.fallbackTime),
zap.Stringer("tx_hash", resp.Hash().Reverse()))
return nil
}
func (c *Client) notaryInvokeAsCommittee(method string, nonce, vub uint32, args ...interface{}) error {
designate, err := c.GetDesignateHash()
if err != nil {
return err
}
return c.notaryInvoke(true, true, designate, nonce, &vub, method, args...)
}
func (c *Client) notaryInvoke(committee, invokedByAlpha bool, contract util.Uint160, nonce uint32, vub *uint32, method string, args ...interface{}) error {
alphabetList, err := c.notary.alphabetSource() // prepare arguments for test invocation
if err != nil {
return err
}
_, n := mn(alphabetList, committee)
u8n := uint8(n)
if !invokedByAlpha {
u8n++
}
cosigners, err := c.notaryCosigners(invokedByAlpha, alphabetList, committee)
if err != nil {
return err
}
params, err := invocationParams(args...)
if err != nil {
return err
}
// make test invocation of the method
test, err := c.client.InvokeFunction(contract, method, params, cosigners)
if err != nil {
return err
}
// check invocation state
if test.State != HaltState {
return wrapNeoFSError(&notHaltStateError{state: test.State, exception: test.FaultException})
}
// if test invocation failed, then return error
if len(test.Script) == 0 {
return wrapNeoFSError(errEmptyInvocationScript)
}
// after test invocation we build main multisig transaction
multiaddrAccount, err := c.notaryMultisigAccount(alphabetList, committee, invokedByAlpha)
if err != nil {
return err
}
var until uint32
if vub != nil {
until = *vub
} else {
until, err = c.notaryTxValidationLimit()
if err != nil {
return err
}
}
// prepare main tx
mainTx := &transaction.Transaction{
Nonce: nonce,
SystemFee: test.GasConsumed,
ValidUntilBlock: until,
Script: test.Script,
Attributes: []transaction.Attribute{
{
Type: transaction.NotaryAssistedT,
Value: &transaction.NotaryAssisted{NKeys: u8n},
},
},
Signers: cosigners,
}
// calculate notary fee
notaryFee, err := c.client.CalculateNotaryFee(u8n)
if err != nil {
return err
}
// add network fee for cosigners
err = c.client.AddNetworkFee(
mainTx,
notaryFee,
c.notaryAccounts(invokedByAlpha, multiaddrAccount)...,
)
if err != nil {
return err
}
// define witnesses
mainTx.Scripts = c.notaryWitnesses(invokedByAlpha, multiaddrAccount, mainTx)
resp, err := c.client.SignAndPushP2PNotaryRequest(mainTx,
[]byte{byte(opcode.RET)},
-1,
0,
c.notary.fallbackTime,
c.acc)
if err != nil && !alreadyOnChainError(err) {
return err
}
c.logger.Debug("notary request invoked",
zap.String("method", method),
zap.Uint32("valid_until_block", until),
zap.Uint32("fallback_valid_for", c.notary.fallbackTime),
zap.Stringer("tx_hash", resp.Hash().Reverse()))
return nil
}
func (c *Client) notaryCosigners(invokedByAlpha bool, ir []*keys.PublicKey, committee bool) ([]transaction.Signer, error) {
s := make([]transaction.Signer, 0, 4)
// first we have proxy contract signature, as it will pay for the execution
s = append(s, transaction.Signer{
Account: c.notary.proxy,
Scopes: transaction.None,
})
// then we have inner ring multiaddress signature
m, _ := mn(ir, committee)
multisigScript, err := sc.CreateMultiSigRedeemScript(m, ir)
if err != nil {
// wrap error as NeoFS-specific since the call is not related to any client
return nil, wrapNeoFSError(fmt.Errorf("can't create ir multisig redeem script: %w", err))
}
s = append(s, transaction.Signer{
Account: hash.Hash160(multisigScript),
Scopes: c.signer.Scopes,
AllowedContracts: c.signer.AllowedContracts,
AllowedGroups: c.signer.AllowedGroups,
})
if !invokedByAlpha {
// then we have invoker signature
s = append(s, transaction.Signer{
Account: hash.Hash160(c.acc.GetVerificationScript()),
Scopes: c.signer.Scopes,
AllowedContracts: c.signer.AllowedContracts,
AllowedGroups: c.signer.AllowedGroups,
})
}
// last one is a placeholder for notary contract signature
s = append(s, transaction.Signer{
Account: c.notary.notary,
Scopes: transaction.None,
})
return s, nil
}
func (c *Client) notaryAccounts(invokedByAlpha bool, multiaddr *wallet.Account) []*wallet.Account {
if multiaddr == nil {
return nil
}
a := make([]*wallet.Account, 0, 4)
// first we have proxy account, as it will pay for the execution
a = append(a, &wallet.Account{
Contract: &wallet.Contract{
Deployed: true,
},
})
// then we have inner ring multiaddress account
a = append(a, multiaddr)
if !invokedByAlpha {
// then we have invoker account
a = append(a, c.acc)
}
// last one is a placeholder for notary contract account
a = append(a, &wallet.Account{
Contract: &wallet.Contract{},
})
return a
}
func (c *Client) notaryWitnesses(invokedByAlpha bool, multiaddr *wallet.Account, tx *transaction.Transaction) []transaction.Witness {
if multiaddr == nil || tx == nil {
return nil
}
w := make([]transaction.Witness, 0, 4)
// first we have empty proxy witness, because notary will execute `Verify`
// method on the proxy contract to check witness
w = append(w, transaction.Witness{
InvocationScript: []byte{},
VerificationScript: []byte{},
})
// then we have inner ring multiaddress witness
// invocation script should be of the form:
// { PUSHDATA1, 64, signatureBytes... }
// to pass Notary module verification
var invokeScript []byte
if invokedByAlpha {
invokeScript = append(
[]byte{byte(opcode.PUSHDATA1), 64},
multiaddr.PrivateKey().SignHashable(uint32(c.client.GetNetwork()), tx)...,
)
} else {
// we can't provide alphabet node signature
// because Storage Node doesn't own alphabet's
// private key. Thus, add dummy witness with
// empty bytes instead of signature
invokeScript = append(
[]byte{byte(opcode.PUSHDATA1), 64},
make([]byte, 64)...,
)
}
w = append(w, transaction.Witness{
InvocationScript: invokeScript,
VerificationScript: multiaddr.GetVerificationScript(),
})
if !invokedByAlpha {
// then we have invoker witness
invokeScript = append(
[]byte{byte(opcode.PUSHDATA1), 64},
c.acc.PrivateKey().SignHashable(uint32(c.client.GetNetwork()), tx)...,
)
w = append(w, transaction.Witness{
InvocationScript: invokeScript,
VerificationScript: c.acc.GetVerificationScript(),
})
}
// last one is a placeholder for notary contract witness
w = append(w, transaction.Witness{
InvocationScript: append(
[]byte{byte(opcode.PUSHDATA1), 64},
make([]byte, 64)...,
),
VerificationScript: []byte{},
})
return w
}
func (c *Client) notaryMultisigAccount(ir []*keys.PublicKey, committee, invokedByAlpha bool) (*wallet.Account, error) {
m, _ := mn(ir, committee)
var multisigAccount *wallet.Account
if invokedByAlpha {
multisigAccount = wallet.NewAccountFromPrivateKey(c.acc.PrivateKey())
err := multisigAccount.ConvertMultisig(m, ir)
if err != nil {
// wrap error as NeoFS-specific since the call is not related to any client
return nil, wrapNeoFSError(fmt.Errorf("can't convert account to inner ring multisig wallet: %w", err))
}
} else {
script, err := smartcontract.CreateMultiSigRedeemScript(m, ir)
if err != nil {
// wrap error as NeoFS-specific since the call is not related to any client
return nil, wrapNeoFSError(fmt.Errorf("can't make inner ring multisig wallet: %w", err))
}
// alphabet multisig redeem script is
// used as verification script for
// inner ring multiaddress witness
multisigAccount = &wallet.Account{
Contract: &wallet.Contract{
Script: script,
},
}
}
return multisigAccount, nil
}
func (c *Client) notaryTxValidationLimit() (uint32, error) {
bc, err := c.client.GetBlockCount()
if err != nil {
return 0, fmt.Errorf("can't get current blockchain height: %w", err)
}
min := bc + c.notary.txValidTime
rounded := (min/c.notary.roundTime + 1) * c.notary.roundTime
return rounded, nil
}
func (c *Client) depositExpirationOf() (int64, error) {
expirationRes, err := c.TestInvoke(c.notary.notary, notaryExpirationOfMethod, c.acc.PrivateKey().GetScriptHash())
if err != nil {
return 0, fmt.Errorf("can't invoke method: %w", err)
}
if len(expirationRes) != 1 {
return 0, fmt.Errorf("method returned unexpected item count: %d", len(expirationRes))
}
currentTillBig, err := expirationRes[0].TryInteger()
if err != nil {
return 0, fmt.Errorf("can't parse deposit till value: %w", err)
}
return currentTillBig.Int64(), nil
}
func invocationParams(args ...interface{}) ([]sc.Parameter, error) {
params := make([]sc.Parameter, 0, len(args))
for i := range args {
param, err := toStackParameter(args[i])
if err != nil {
return nil, err
}
params = append(params, param)
}
return params, nil
}
// mn returns M and N multi signature numbers. For NeoFS N is a length of
// inner ring list, and M is a 2/3+1 of it (like in dBFT). If committee is
// true, returns M as N/2+1.
func mn(ir []*keys.PublicKey, committee bool) (m int, n int) {
n = len(ir)
if committee {
m = n/2 + 1
} else {
m = n*2/3 + 1
}
return
}
// WithTxValidTime returns a notary support option for client
// that specifies minimum amount of blocks when mainTx will be valid.
func WithTxValidTime(t uint32) NotaryOption {
return func(c *notaryCfg) {
c.txValidTime = t
}
}
// WithRoundTime returns a notary support option for client
// that specifies extra blocks to synchronize side chain
// height diff of inner ring nodes.
func WithRoundTime(t uint32) NotaryOption {
return func(c *notaryCfg) {
c.roundTime = t
}
}
// WithFallbackTime returns a notary support option for client
// that specifies amount of blocks before fallbackTx will be sent.
// Should be less than TxValidTime.
func WithFallbackTime(t uint32) NotaryOption {
return func(c *notaryCfg) {
c.fallbackTime = t
}
}
// WithAlphabetSource returns a notary support option for client
// that specifies function to return list of alphabet node keys.
// By default notary subsystem uses committee as a source. This is
// valid for side chain but notary in main chain should override it.
func WithAlphabetSource(t AlphabetKeys) NotaryOption {
return func(c *notaryCfg) {
c.alphabetSource = t
}
}
// WithProxyContract sets proxy contract hash.
func WithProxyContract(h util.Uint160) NotaryOption {
return func(c *notaryCfg) {
c.proxy = h
}
}
// Neo RPC node can return `core.ErrInvalidAttribute` error with
// `conflicting transaction <> is already on chain` message. This
// error is expected and ignored. As soon as main tx persisted on
// chain everything is fine. This happens because notary contract
// requires 5 out of 7 signatures to send main tx, thus last two
// notary requests may be processed after main tx appeared on chain.
func alreadyOnChainError(err error) bool {
const alreadyOnChainErrorMessage = "already on chain"
return strings.Contains(err.Error(), alreadyOnChainErrorMessage)
}
// CalculateNotaryDepositAmount calculates notary deposit amount
// using the rule:
// IF notaryBalance < gasBalance * gasMul {
// DEPOSIT gasBalance / gasDiv
// } ELSE {
// DEPOSIT 1
// }
// gasMul and gasDiv must be positive.
func CalculateNotaryDepositAmount(c *Client, gasMul, gasDiv int64) (fixedn.Fixed8, error) {
notaryBalance, err := c.GetNotaryDeposit()
if err != nil {
return 0, fmt.Errorf("could not get notary balance: %w", err)
}
gasBalance, err := c.GasBalance()
if err != nil {
return 0, fmt.Errorf("could not get GAS balance: %w", err)
}
var depositAmount int64
if gasBalance*gasMul > notaryBalance {
depositAmount = gasBalance / gasDiv
} else {
depositAmount = 1
}
return fixedn.Fixed8(depositAmount), nil
}
// CalculateNonceAndVUB calculates nonce and ValidUntilBlock values
// based on transaction hash. Uses MurmurHash3.
func (c *Client) CalculateNonceAndVUB(hash util.Uint256) (nonce uint32, vub uint32, err error) {
if c.multiClient != nil {
return nonce, vub, c.multiClient.iterateClients(func(c *Client) error {
nonce, vub, err = c.CalculateNonceAndVUB(hash)
return err
})
}
if c.notary == nil {
return 0, 0, nil
}
// TODO: #1151 cache values since some operations uses same TX as triggers
nonce = binary.LittleEndian.Uint32(hash.BytesLE())
height, err := c.client.GetTransactionHeight(hash)
if err != nil {
return 0, 0, fmt.Errorf("could not get transaction height: %w", err)
}
return nonce, height + c.notary.txValidTime, nil
}