From 182d9cb752ffe08fc5e40718031bc8a497311ff5 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?P=C3=A9ter=20Szil=C3=A1gyi?= Date: Fri, 14 Oct 2016 15:32:06 +0300 Subject: core: add global (soft) limits on the pending transactions --- core/tx_pool.go | 65 ++++++++++++++++++++++++++++++++++--- core/tx_pool_test.go | 90 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 150 insertions(+), 5 deletions(-) (limited to 'core') diff --git a/core/tx_pool.go b/core/tx_pool.go index 4c9410d8e..2c8a5c396 100644 --- a/core/tx_pool.go +++ b/core/tx_pool.go @@ -30,6 +30,7 @@ import ( "github.com/ethereum/go-ethereum/event" "github.com/ethereum/go-ethereum/logger" "github.com/ethereum/go-ethereum/logger/glog" + "gopkg.in/karalabe/cookiejar.v2/collections/prque" ) var ( @@ -46,10 +47,12 @@ var ( ) var ( - maxQueuedPerAccount = uint64(64) // Max limit of queued transactions per address - maxQueuedInTotal = uint64(8192) // Max limit of queued transactions from all accounts - maxQueuedLifetime = 3 * time.Hour // Max amount of time transactions from idle accounts are queued - evictionInterval = time.Minute // Time interval to check for evictable transactions + minPendingPerAccount = uint64(16) // Min number of guaranteed transaction slots per address + maxPendingTotal = uint64(4096) // Max limit of pending transactions from all accounts (soft) + maxQueuedPerAccount = uint64(64) // Max limit of queued transactions per address + maxQueuedInTotal = uint64(1024) // Max limit of queued transactions from all accounts + maxQueuedLifetime = 3 * time.Hour // Max amount of time transactions from idle accounts are queued + evictionInterval = time.Minute // Time interval to check for evictable transactions ) type stateFn func() (*state.StateDB, error) @@ -481,7 +484,6 @@ func (pool *TxPool) promoteExecutables() { } // Iterate over all accounts and promote any executable transactions queued := uint64(0) - for addr, list := range pool.queue { // Drop all transactions that are deemed too old (low nonce) for _, tx := range list.Forward(state.GetNonce(addr)) { @@ -519,6 +521,59 @@ func (pool *TxPool) promoteExecutables() { delete(pool.queue, addr) } } + // If the pending limit is overflown, start equalizing allowances + pending := uint64(0) + for _, list := range pool.pending { + pending += uint64(list.Len()) + } + if pending > maxPendingTotal { + // Assemble a spam order to penalize large transactors first + spammers := prque.New() + for addr, list := range pool.pending { + // Only evict transactions from high rollers + if uint64(list.Len()) > minPendingPerAccount { + // Skip local accounts as pools should maintain backlogs for themselves + for _, tx := range list.txs.items { + if !pool.localTx.contains(tx.Hash()) { + spammers.Push(addr, float32(list.Len())) + } + break // Checking on transaction for locality is enough + } + } + } + // Gradually drop transactions from offenders + offenders := []common.Address{} + for pending > maxPendingTotal && !spammers.Empty() { + // Retrieve the next offender if not local address + offender, _ := spammers.Pop() + offenders = append(offenders, offender.(common.Address)) + + // Equalize balances until all the same or below threshold + if len(offenders) > 1 { + // Calculate the equalization threshold for all current offenders + threshold := pool.pending[offender.(common.Address)].Len() + + // Iteratively reduce all offenders until below limit or threshold reached + for pending > maxPendingTotal && pool.pending[offenders[len(offenders)-2]].Len() > threshold { + for i := 0; i < len(offenders)-1; i++ { + list := pool.pending[offenders[i]] + list.Cap(list.Len() - 1) + pending-- + } + } + } + } + // If still above threshold, reduce to limit or min allowance + if pending > maxPendingTotal && len(offenders) > 0 { + for pending > maxPendingTotal && uint64(pool.pending[offenders[len(offenders)-1]].Len()) > minPendingPerAccount { + for _, addr := range offenders { + list := pool.pending[addr] + list.Cap(list.Len() - 1) + pending-- + } + } + } + } // If we've queued more transactions than the hard limit, drop oldest ones if queued > maxQueuedInTotal { // Sort all accounts with queued transactions by heartbeat diff --git a/core/tx_pool_test.go b/core/tx_pool_test.go index 4bc5aed38..dbe6fa635 100644 --- a/core/tx_pool_test.go +++ b/core/tx_pool_test.go @@ -618,6 +618,96 @@ func testTransactionLimitingEquivalency(t *testing.T, origin uint64) { } } +// Tests that if the transaction count belonging to multiple accounts go above +// some hard threshold, the higher transactions are dropped to prevent DOS +// attacks. +func TestTransactionPendingGlobalLimiting(t *testing.T) { + // Reduce the queue limits to shorten test time + defer func(old uint64) { maxPendingTotal = old }(maxPendingTotal) + maxPendingTotal = minPendingPerAccount * 10 + + // Create the pool to test the limit enforcement with + db, _ := ethdb.NewMemDatabase() + statedb, _ := state.New(common.Hash{}, db) + + pool := NewTxPool(testChainConfig(), new(event.TypeMux), func() (*state.StateDB, error) { return statedb, nil }, func() *big.Int { return big.NewInt(1000000) }) + pool.resetState() + + // Create a number of test accounts and fund them + state, _ := pool.currentState() + + keys := make([]*ecdsa.PrivateKey, 5) + for i := 0; i < len(keys); i++ { + keys[i], _ = crypto.GenerateKey() + state.AddBalance(crypto.PubkeyToAddress(keys[i].PublicKey), big.NewInt(1000000)) + } + // Generate and queue a batch of transactions + nonces := make(map[common.Address]uint64) + + txs := types.Transactions{} + for _, key := range keys { + addr := crypto.PubkeyToAddress(key.PublicKey) + for j := 0; j < int(maxPendingTotal)/len(keys)*2; j++ { + txs = append(txs, transaction(nonces[addr], big.NewInt(100000), key)) + nonces[addr]++ + } + } + // Import the batch and verify that limits have been enforced + pool.AddBatch(txs) + + pending := 0 + for _, list := range pool.pending { + pending += list.Len() + } + if pending > int(maxPendingTotal) { + t.Fatalf("total pending transactions overflow allowance: %d > %d", pending, maxPendingTotal) + } +} + +// Tests that if the transaction count belonging to multiple accounts go above +// some hard threshold, if they are under the minimum guaranteed slot count then +// the transactions are still kept. +func TestTransactionPendingMinimumAllowance(t *testing.T) { + // Reduce the queue limits to shorten test time + defer func(old uint64) { maxPendingTotal = old }(maxPendingTotal) + maxPendingTotal = 0 + + // Create the pool to test the limit enforcement with + db, _ := ethdb.NewMemDatabase() + statedb, _ := state.New(common.Hash{}, db) + + pool := NewTxPool(testChainConfig(), new(event.TypeMux), func() (*state.StateDB, error) { return statedb, nil }, func() *big.Int { return big.NewInt(1000000) }) + pool.resetState() + + // Create a number of test accounts and fund them + state, _ := pool.currentState() + + keys := make([]*ecdsa.PrivateKey, 5) + for i := 0; i < len(keys); i++ { + keys[i], _ = crypto.GenerateKey() + state.AddBalance(crypto.PubkeyToAddress(keys[i].PublicKey), big.NewInt(1000000)) + } + // Generate and queue a batch of transactions + nonces := make(map[common.Address]uint64) + + txs := types.Transactions{} + for _, key := range keys { + addr := crypto.PubkeyToAddress(key.PublicKey) + for j := 0; j < int(minPendingPerAccount)*2; j++ { + txs = append(txs, transaction(nonces[addr], big.NewInt(100000), key)) + nonces[addr]++ + } + } + // Import the batch and verify that limits have been enforced + pool.AddBatch(txs) + + for addr, list := range pool.pending { + if list.Len() != int(minPendingPerAccount) { + t.Errorf("addr %x: total pending transactions mismatch: have %d, want %d", addr, list.Len(), minPendingPerAccount) + } + } +} + // Benchmarks the speed of validating the contents of the pending queue of the // transaction pool. func BenchmarkPendingDemotion100(b *testing.B) { benchmarkPendingDemotion(b, 100) } -- cgit v1.2.3