mirror of
https://github.com/nspcc-dev/neo-go.git
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c5cdaae87a
It should be called for NEO contract to distribute committee bounties.
539 lines
16 KiB
Go
539 lines
16 KiB
Go
package native
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import (
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"encoding/binary"
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"errors"
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"fmt"
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"math/big"
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"sort"
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"sync"
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"github.com/nspcc-dev/neo-go/pkg/core/dao"
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"github.com/nspcc-dev/neo-go/pkg/core/interop"
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"github.com/nspcc-dev/neo-go/pkg/core/interop/runtime"
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"github.com/nspcc-dev/neo-go/pkg/core/state"
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"github.com/nspcc-dev/neo-go/pkg/core/transaction"
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"github.com/nspcc-dev/neo-go/pkg/network/payload"
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"github.com/nspcc-dev/neo-go/pkg/smartcontract"
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"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
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"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
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)
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const (
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policyName = "Policy"
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policyContractID = -3
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defaultMaxBlockSize = 1024 * 256
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defaultMaxTransactionsPerBlock = 512
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defaultFeePerByte = 1000
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defaultMaxVerificationGas = 50000000
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defaultMaxBlockSystemFee = 9000 * GASFactor
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// minBlockSystemFee is the minimum allowed system fee per block.
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minBlockSystemFee = 4007600
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)
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var (
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// maxTransactionsPerBlockKey is a key used to store the maximum number of
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// transactions allowed in block.
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maxTransactionsPerBlockKey = []byte{23}
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// feePerByteKey is a key used to store the minimum fee per byte for
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// transaction.
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feePerByteKey = []byte{10}
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// blockedAccountsKey is a key used to store the list of blocked accounts.
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blockedAccountsKey = []byte{15}
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// maxBlockSizeKey is a key used to store the maximum block size value.
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maxBlockSizeKey = []byte{12}
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// maxBlockSystemFeeKey is a key used to store the maximum block system fee value.
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maxBlockSystemFeeKey = []byte{17}
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)
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// Policy represents Policy native contract.
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type Policy struct {
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interop.ContractMD
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lock sync.RWMutex
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// isValid defies whether cached values were changed during the current
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// consensus iteration. If false, these values will be updated after
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// blockchain DAO persisting. If true, we can safely use cached values.
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isValid bool
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maxTransactionsPerBlock uint32
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maxBlockSize uint32
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feePerByte int64
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maxBlockSystemFee int64
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maxVerificationGas int64
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}
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var _ interop.Contract = (*Policy)(nil)
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// newPolicy returns Policy native contract.
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func newPolicy() *Policy {
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p := &Policy{ContractMD: *interop.NewContractMD(policyName)}
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p.ContractID = policyContractID
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p.Manifest.Features |= smartcontract.HasStorage
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desc := newDescriptor("getMaxTransactionsPerBlock", smartcontract.IntegerType)
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md := newMethodAndPrice(p.getMaxTransactionsPerBlock, 1000000, smartcontract.AllowStates)
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p.AddMethod(md, desc, true)
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desc = newDescriptor("getMaxBlockSize", smartcontract.IntegerType)
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md = newMethodAndPrice(p.getMaxBlockSize, 1000000, smartcontract.AllowStates)
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p.AddMethod(md, desc, true)
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desc = newDescriptor("getFeePerByte", smartcontract.IntegerType)
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md = newMethodAndPrice(p.getFeePerByte, 1000000, smartcontract.AllowStates)
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p.AddMethod(md, desc, true)
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desc = newDescriptor("getBlockedAccounts", smartcontract.ArrayType)
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md = newMethodAndPrice(p.getBlockedAccounts, 1000000, smartcontract.AllowStates)
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p.AddMethod(md, desc, true)
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desc = newDescriptor("getMaxBlockSystemFee", smartcontract.IntegerType)
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md = newMethodAndPrice(p.getMaxBlockSystemFee, 1000000, smartcontract.AllowStates)
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p.AddMethod(md, desc, true)
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desc = newDescriptor("setMaxBlockSize", smartcontract.BoolType,
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manifest.NewParameter("value", smartcontract.IntegerType))
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md = newMethodAndPrice(p.setMaxBlockSize, 3000000, smartcontract.AllowModifyStates)
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p.AddMethod(md, desc, false)
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desc = newDescriptor("setMaxTransactionsPerBlock", smartcontract.BoolType,
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manifest.NewParameter("value", smartcontract.IntegerType))
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md = newMethodAndPrice(p.setMaxTransactionsPerBlock, 3000000, smartcontract.AllowModifyStates)
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p.AddMethod(md, desc, false)
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desc = newDescriptor("setFeePerByte", smartcontract.BoolType,
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manifest.NewParameter("value", smartcontract.IntegerType))
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md = newMethodAndPrice(p.setFeePerByte, 3000000, smartcontract.AllowModifyStates)
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p.AddMethod(md, desc, false)
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desc = newDescriptor("setMaxBlockSystemFee", smartcontract.BoolType,
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manifest.NewParameter("value", smartcontract.IntegerType))
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md = newMethodAndPrice(p.setMaxBlockSystemFee, 3000000, smartcontract.AllowModifyStates)
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p.AddMethod(md, desc, false)
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desc = newDescriptor("blockAccount", smartcontract.BoolType,
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manifest.NewParameter("account", smartcontract.Hash160Type))
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md = newMethodAndPrice(p.blockAccount, 3000000, smartcontract.AllowModifyStates)
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p.AddMethod(md, desc, false)
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desc = newDescriptor("unblockAccount", smartcontract.BoolType,
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manifest.NewParameter("account", smartcontract.Hash160Type))
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md = newMethodAndPrice(p.unblockAccount, 3000000, smartcontract.AllowModifyStates)
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p.AddMethod(md, desc, false)
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desc = newDescriptor("onPersist", smartcontract.VoidType)
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md = newMethodAndPrice(getOnPersistWrapper(p.OnPersist), 0, smartcontract.AllowModifyStates)
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p.AddMethod(md, desc, false)
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desc = newDescriptor("postPersist", smartcontract.VoidType)
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md = newMethodAndPrice(getOnPersistWrapper(postPersistBase), 0, smartcontract.AllowModifyStates)
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p.AddMethod(md, desc, false)
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return p
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}
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// Metadata implements Contract interface.
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func (p *Policy) Metadata() *interop.ContractMD {
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return &p.ContractMD
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}
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// Initialize initializes Policy native contract and implements Contract interface.
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func (p *Policy) Initialize(ic *interop.Context) error {
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si := &state.StorageItem{
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Value: make([]byte, 4, 8),
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}
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binary.LittleEndian.PutUint32(si.Value, defaultMaxBlockSize)
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err := ic.DAO.PutStorageItem(p.ContractID, maxBlockSizeKey, si)
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if err != nil {
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return err
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}
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binary.LittleEndian.PutUint32(si.Value, defaultMaxTransactionsPerBlock)
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err = ic.DAO.PutStorageItem(p.ContractID, maxTransactionsPerBlockKey, si)
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if err != nil {
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return err
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}
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si.Value = si.Value[:8]
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binary.LittleEndian.PutUint64(si.Value, defaultFeePerByte)
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err = ic.DAO.PutStorageItem(p.ContractID, feePerByteKey, si)
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if err != nil {
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return err
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}
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binary.LittleEndian.PutUint64(si.Value, defaultMaxBlockSystemFee)
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err = ic.DAO.PutStorageItem(p.ContractID, maxBlockSystemFeeKey, si)
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if err != nil {
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return err
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}
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ba := new(BlockedAccounts)
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si.Value = ba.Bytes()
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err = ic.DAO.PutStorageItem(p.ContractID, blockedAccountsKey, si)
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if err != nil {
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return err
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}
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p.isValid = true
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p.maxTransactionsPerBlock = defaultMaxTransactionsPerBlock
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p.maxBlockSize = defaultMaxBlockSize
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p.feePerByte = defaultFeePerByte
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p.maxBlockSystemFee = defaultMaxBlockSystemFee
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p.maxVerificationGas = defaultMaxVerificationGas
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return nil
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}
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// OnPersist implements Contract interface.
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func (p *Policy) OnPersist(ic *interop.Context) error {
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return nil
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}
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// OnPersistEnd updates cached Policy values if they've been changed
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func (p *Policy) OnPersistEnd(dao dao.DAO) {
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if p.isValid {
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return
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}
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p.lock.Lock()
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defer p.lock.Unlock()
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maxTxPerBlock := p.getUint32WithKey(dao, maxTransactionsPerBlockKey)
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p.maxTransactionsPerBlock = maxTxPerBlock
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maxBlockSize := p.getUint32WithKey(dao, maxBlockSizeKey)
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p.maxBlockSize = maxBlockSize
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feePerByte := p.getInt64WithKey(dao, feePerByteKey)
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p.feePerByte = feePerByte
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maxBlockSystemFee := p.getInt64WithKey(dao, maxBlockSystemFeeKey)
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p.maxBlockSystemFee = maxBlockSystemFee
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p.maxVerificationGas = defaultMaxVerificationGas
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p.isValid = true
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}
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// getMaxTransactionsPerBlock is Policy contract method and returns the upper
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// limit of transactions per block.
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func (p *Policy) getMaxTransactionsPerBlock(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
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return stackitem.NewBigInteger(big.NewInt(int64(p.GetMaxTransactionsPerBlockInternal(ic.DAO))))
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}
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// GetMaxTransactionsPerBlockInternal returns the upper limit of transactions per
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// block.
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func (p *Policy) GetMaxTransactionsPerBlockInternal(dao dao.DAO) uint32 {
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p.lock.RLock()
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defer p.lock.RUnlock()
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if p.isValid {
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return p.maxTransactionsPerBlock
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}
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return p.getUint32WithKey(dao, maxTransactionsPerBlockKey)
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}
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// getMaxBlockSize is Policy contract method and returns maximum block size.
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func (p *Policy) getMaxBlockSize(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
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return stackitem.NewBigInteger(big.NewInt(int64(p.GetMaxBlockSizeInternal(ic.DAO))))
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}
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// GetMaxBlockSizeInternal returns maximum block size.
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func (p *Policy) GetMaxBlockSizeInternal(dao dao.DAO) uint32 {
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p.lock.RLock()
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defer p.lock.RUnlock()
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if p.isValid {
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return p.maxBlockSize
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}
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return p.getUint32WithKey(dao, maxBlockSizeKey)
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}
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// getFeePerByte is Policy contract method and returns required transaction's fee
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// per byte.
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func (p *Policy) getFeePerByte(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
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return stackitem.NewBigInteger(big.NewInt(p.GetFeePerByteInternal(ic.DAO)))
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}
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// GetFeePerByteInternal returns required transaction's fee per byte.
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func (p *Policy) GetFeePerByteInternal(dao dao.DAO) int64 {
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p.lock.RLock()
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defer p.lock.RUnlock()
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if p.isValid {
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return p.feePerByte
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}
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return p.getInt64WithKey(dao, feePerByteKey)
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}
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// GetMaxVerificationGas returns maximum gas allowed to be burned during verificaion.
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func (p *Policy) GetMaxVerificationGas(_ dao.DAO) int64 {
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if p.isValid {
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return p.maxVerificationGas
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}
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return defaultMaxVerificationGas
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}
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// getMaxBlockSystemFee is Policy contract method and returns the maximum overall
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// system fee per block.
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func (p *Policy) getMaxBlockSystemFee(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
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return stackitem.NewBigInteger(big.NewInt(p.GetMaxBlockSystemFeeInternal(ic.DAO)))
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}
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// GetMaxBlockSystemFeeInternal the maximum overall system fee per block.
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func (p *Policy) GetMaxBlockSystemFeeInternal(dao dao.DAO) int64 {
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p.lock.RLock()
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defer p.lock.RUnlock()
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if p.isValid {
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return p.maxBlockSystemFee
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}
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return p.getInt64WithKey(dao, maxBlockSystemFeeKey)
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}
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// getBlockedAccounts is Policy contract method and returns list of blocked
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// accounts hashes.
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func (p *Policy) getBlockedAccounts(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
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ba, err := p.GetBlockedAccountsInternal(ic.DAO)
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if err != nil {
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panic(err)
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}
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return ba.ToStackItem()
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}
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// GetBlockedAccountsInternal returns list of blocked accounts hashes.
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func (p *Policy) GetBlockedAccountsInternal(dao dao.DAO) (BlockedAccounts, error) {
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si := dao.GetStorageItem(p.ContractID, blockedAccountsKey)
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if si == nil {
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return nil, errors.New("BlockedAccounts uninitialized")
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}
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ba, err := BlockedAccountsFromBytes(si.Value)
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if err != nil {
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return nil, err
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}
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return ba, nil
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}
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// setMaxTransactionsPerBlock is Policy contract method and sets the upper limit
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// of transactions per block.
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func (p *Policy) setMaxTransactionsPerBlock(ic *interop.Context, args []stackitem.Item) stackitem.Item {
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ok, err := p.checkValidators(ic)
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if err != nil {
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panic(err)
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}
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if !ok {
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return stackitem.NewBool(false)
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}
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value := uint32(toBigInt(args[0]).Int64())
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p.lock.Lock()
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defer p.lock.Unlock()
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err = p.setUint32WithKey(ic.DAO, maxTransactionsPerBlockKey, value)
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if err != nil {
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panic(err)
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}
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p.isValid = false
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return stackitem.NewBool(true)
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}
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// setMaxBlockSize is Policy contract method and sets maximum block size.
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func (p *Policy) setMaxBlockSize(ic *interop.Context, args []stackitem.Item) stackitem.Item {
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ok, err := p.checkValidators(ic)
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if err != nil {
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panic(err)
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}
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if !ok {
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return stackitem.NewBool(false)
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}
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value := uint32(toBigInt(args[0]).Int64())
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if payload.MaxSize <= value {
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return stackitem.NewBool(false)
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}
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p.lock.Lock()
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defer p.lock.Unlock()
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err = p.setUint32WithKey(ic.DAO, maxBlockSizeKey, value)
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if err != nil {
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panic(err)
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}
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p.isValid = false
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return stackitem.NewBool(true)
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}
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// setFeePerByte is Policy contract method and sets transaction's fee per byte.
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func (p *Policy) setFeePerByte(ic *interop.Context, args []stackitem.Item) stackitem.Item {
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ok, err := p.checkValidators(ic)
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if err != nil {
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panic(err)
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}
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if !ok {
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return stackitem.NewBool(false)
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}
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value := toBigInt(args[0]).Int64()
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p.lock.Lock()
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defer p.lock.Unlock()
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err = p.setInt64WithKey(ic.DAO, feePerByteKey, value)
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if err != nil {
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panic(err)
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}
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p.isValid = false
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return stackitem.NewBool(true)
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}
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// setMaxBlockSystemFee is Policy contract method and sets the maximum system fee per block.
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func (p *Policy) setMaxBlockSystemFee(ic *interop.Context, args []stackitem.Item) stackitem.Item {
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ok, err := p.checkValidators(ic)
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if err != nil {
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panic(err)
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}
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if !ok {
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return stackitem.NewBool(false)
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}
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value := toBigInt(args[0]).Int64()
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if value <= minBlockSystemFee {
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return stackitem.NewBool(false)
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}
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p.lock.Lock()
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defer p.lock.Unlock()
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err = p.setInt64WithKey(ic.DAO, maxBlockSystemFeeKey, value)
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if err != nil {
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panic(err)
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}
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p.isValid = false
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return stackitem.NewBool(true)
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}
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// blockAccount is Policy contract method and adds given account hash to the list
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// of blocked accounts.
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func (p *Policy) blockAccount(ic *interop.Context, args []stackitem.Item) stackitem.Item {
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ok, err := p.checkValidators(ic)
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if err != nil {
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panic(err)
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}
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if !ok {
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return stackitem.NewBool(false)
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}
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value := toUint160(args[0])
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si := ic.DAO.GetStorageItem(p.ContractID, blockedAccountsKey)
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if si == nil {
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panic("BlockedAccounts uninitialized")
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}
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ba, err := BlockedAccountsFromBytes(si.Value)
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if err != nil {
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panic(err)
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}
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indexToInsert := sort.Search(len(ba), func(i int) bool {
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return !ba[i].Less(value)
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})
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ba = append(ba, value)
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if indexToInsert != len(ba)-1 && ba[indexToInsert].Equals(value) {
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return stackitem.NewBool(false)
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}
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if len(ba) > 1 {
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copy(ba[indexToInsert+1:], ba[indexToInsert:])
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ba[indexToInsert] = value
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}
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err = ic.DAO.PutStorageItem(p.ContractID, blockedAccountsKey, &state.StorageItem{
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Value: ba.Bytes(),
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})
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if err != nil {
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panic(err)
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}
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return stackitem.NewBool(true)
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}
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// unblockAccount is Policy contract method and removes given account hash from
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// the list of blocked accounts.
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func (p *Policy) unblockAccount(ic *interop.Context, args []stackitem.Item) stackitem.Item {
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ok, err := p.checkValidators(ic)
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if err != nil {
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panic(err)
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}
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if !ok {
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return stackitem.NewBool(false)
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}
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value := toUint160(args[0])
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si := ic.DAO.GetStorageItem(p.ContractID, blockedAccountsKey)
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if si == nil {
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panic("BlockedAccounts uninitialized")
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}
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ba, err := BlockedAccountsFromBytes(si.Value)
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if err != nil {
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panic(err)
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}
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indexToRemove := sort.Search(len(ba), func(i int) bool {
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return !ba[i].Less(value)
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})
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if indexToRemove == len(ba) || !ba[indexToRemove].Equals(value) {
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return stackitem.NewBool(false)
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}
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ba = append(ba[:indexToRemove], ba[indexToRemove+1:]...)
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err = ic.DAO.PutStorageItem(p.ContractID, blockedAccountsKey, &state.StorageItem{
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Value: ba.Bytes(),
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})
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if err != nil {
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panic(err)
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}
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return stackitem.NewBool(true)
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}
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func (p *Policy) getUint32WithKey(dao dao.DAO, key []byte) uint32 {
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si := dao.GetStorageItem(p.ContractID, key)
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if si == nil {
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return 0
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}
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return binary.LittleEndian.Uint32(si.Value)
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}
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func (p *Policy) setUint32WithKey(dao dao.DAO, key []byte, value uint32) error {
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si := dao.GetStorageItem(p.ContractID, key)
|
|
binary.LittleEndian.PutUint32(si.Value, value)
|
|
err := dao.PutStorageItem(p.ContractID, key, si)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (p *Policy) getInt64WithKey(dao dao.DAO, key []byte) int64 {
|
|
si := dao.GetStorageItem(p.ContractID, key)
|
|
if si == nil {
|
|
return 0
|
|
}
|
|
return int64(binary.LittleEndian.Uint64(si.Value))
|
|
}
|
|
|
|
func (p *Policy) setInt64WithKey(dao dao.DAO, key []byte, value int64) error {
|
|
si := dao.GetStorageItem(p.ContractID, key)
|
|
binary.LittleEndian.PutUint64(si.Value, uint64(value))
|
|
err := dao.PutStorageItem(p.ContractID, key, si)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (p *Policy) checkValidators(ic *interop.Context) (bool, error) {
|
|
prevBlock, err := ic.Chain.GetBlock(ic.Block.PrevHash)
|
|
if err != nil {
|
|
return false, err
|
|
}
|
|
return runtime.CheckHashedWitness(ic, prevBlock.NextConsensus)
|
|
}
|
|
|
|
// 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 {
|
|
ba, err := p.GetBlockedAccountsInternal(d)
|
|
if err != nil {
|
|
return fmt.Errorf("unable to get blocked accounts list: %w", err)
|
|
}
|
|
if len(ba) > 0 {
|
|
for _, signer := range tx.Signers {
|
|
i := sort.Search(len(ba), func(i int) bool {
|
|
return !ba[i].Less(signer.Account)
|
|
})
|
|
if i != len(ba) && ba[i].Equals(signer.Account) {
|
|
return fmt.Errorf("account %s is blocked", signer.Account.StringLE())
|
|
}
|
|
}
|
|
}
|
|
maxBlockSystemFee := p.GetMaxBlockSystemFeeInternal(d)
|
|
if maxBlockSystemFee < tx.SystemFee {
|
|
return fmt.Errorf("transaction's fee can't exceed maximum block system fee %d", maxBlockSystemFee)
|
|
}
|
|
return nil
|
|
}
|