/ src / test / txvalidation_tests.cpp
txvalidation_tests.cpp
  1  // Copyright (c) 2017-present The Bitcoin Core developers
  2  // Distributed under the MIT software license, see the accompanying
  3  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  4  
  5  #include <consensus/validation.h>
  6  #include <key_io.h>
  7  #include <policy/packages.h>
  8  #include <policy/policy.h>
  9  #include <policy/ephemeral_policy.h>
 10  #include <policy/truc_policy.h>
 11  #include <primitives/transaction.h>
 12  #include <random.h>
 13  #include <script/script.h>
 14  #include <test/util/common.h>
 15  #include <test/util/setup_common.h>
 16  #include <test/util/txmempool.h>
 17  #include <validation.h>
 18  
 19  #include <boost/test/unit_test.hpp>
 20  
 21  
 22  BOOST_AUTO_TEST_SUITE(txvalidation_tests)
 23  
 24  /**
 25   * Ensure that the mempool won't accept coinbase transactions.
 26   */
 27  BOOST_FIXTURE_TEST_CASE(tx_mempool_reject_coinbase, TestChain100Setup)
 28  {
 29      CScript scriptPubKey = CScript() << ToByteVector(coinbaseKey.GetPubKey()) << OP_CHECKSIG;
 30      CMutableTransaction coinbaseTx;
 31  
 32      coinbaseTx.version = 1;
 33      coinbaseTx.vin.resize(1);
 34      coinbaseTx.vout.resize(1);
 35      coinbaseTx.vin[0].scriptSig = CScript() << OP_11 << OP_EQUAL;
 36      coinbaseTx.vout[0].nValue = 1 * CENT;
 37      coinbaseTx.vout[0].scriptPubKey = scriptPubKey;
 38  
 39      BOOST_CHECK(CTransaction(coinbaseTx).IsCoinBase());
 40  
 41      LOCK(cs_main);
 42  
 43      unsigned int initialPoolSize = m_node.mempool->size();
 44      const MempoolAcceptResult result = m_node.chainman->ProcessTransaction(MakeTransactionRef(coinbaseTx));
 45  
 46      BOOST_CHECK(result.m_result_type == MempoolAcceptResult::ResultType::INVALID);
 47  
 48      // Check that the transaction hasn't been added to mempool.
 49      BOOST_CHECK_EQUAL(m_node.mempool->size(), initialPoolSize);
 50  
 51      // Check that the validation state reflects the unsuccessful attempt.
 52      BOOST_CHECK(result.m_state.IsInvalid());
 53      BOOST_CHECK_EQUAL(result.m_state.GetRejectReason(), "coinbase");
 54      BOOST_CHECK(result.m_state.GetResult() == TxValidationResult::TX_CONSENSUS);
 55  }
 56  
 57  // Generate a number of random, nonexistent outpoints.
 58  static inline std::vector<COutPoint> random_outpoints(size_t num_outpoints) {
 59      std::vector<COutPoint> outpoints;
 60      for (size_t i{0}; i < num_outpoints; ++i) {
 61          outpoints.emplace_back(Txid::FromUint256(GetRandHash()), 0);
 62      }
 63      return outpoints;
 64  }
 65  
 66  static inline std::vector<CPubKey> random_keys(size_t num_keys) {
 67      std::vector<CPubKey> keys;
 68      keys.reserve(num_keys);
 69      for (size_t i{0}; i < num_keys; ++i) {
 70          CKey key;
 71          key.MakeNewKey(true);
 72          keys.emplace_back(key.GetPubKey());
 73      }
 74      return keys;
 75  }
 76  
 77  // Creates a placeholder tx (not valid) with 25 outputs. Specify the version and the inputs.
 78  static inline CTransactionRef make_tx(const std::vector<COutPoint>& inputs, int32_t version)
 79  {
 80      CMutableTransaction mtx = CMutableTransaction{};
 81      mtx.version = version;
 82      mtx.vin.resize(inputs.size());
 83      mtx.vout.resize(25);
 84      for (size_t i{0}; i < inputs.size(); ++i) {
 85          mtx.vin[i].prevout = inputs[i];
 86      }
 87      for (auto i{0}; i < 25; ++i) {
 88          mtx.vout[i].scriptPubKey = CScript() << OP_TRUE;
 89          mtx.vout[i].nValue = 10000;
 90      }
 91      return MakeTransactionRef(mtx);
 92  }
 93  
 94  static constexpr auto NUM_EPHEMERAL_TX_OUTPUTS = 3;
 95  static constexpr auto EPHEMERAL_DUST_INDEX = NUM_EPHEMERAL_TX_OUTPUTS - 1;
 96  
 97  // Same as make_tx but adds 2 normal outputs and 0-value dust to end of vout
 98  static inline CTransactionRef make_ephemeral_tx(const std::vector<COutPoint>& inputs, int32_t version)
 99  {
100      CMutableTransaction mtx = CMutableTransaction{};
101      mtx.version = version;
102      mtx.vin.resize(inputs.size());
103      for (size_t i{0}; i < inputs.size(); ++i) {
104          mtx.vin[i].prevout = inputs[i];
105      }
106      mtx.vout.resize(NUM_EPHEMERAL_TX_OUTPUTS);
107      for (auto i{0}; i < NUM_EPHEMERAL_TX_OUTPUTS; ++i) {
108          mtx.vout[i].scriptPubKey = CScript() << OP_TRUE;
109          mtx.vout[i].nValue = (i == EPHEMERAL_DUST_INDEX) ? 0 : 10000;
110      }
111      return MakeTransactionRef(mtx);
112  }
113  
114  BOOST_FIXTURE_TEST_CASE(ephemeral_tests, RegTestingSetup)
115  {
116      CTxMemPool& pool = *Assert(m_node.mempool);
117      LOCK2(cs_main, pool.cs);
118      TestMemPoolEntryHelper entry;
119  
120      TxValidationState child_state;
121      Wtxid child_wtxid;
122  
123      // Arbitrary non-0 feerate for these tests
124      CFeeRate dustrelay(DUST_RELAY_TX_FEE);
125  
126      // Basic transaction with dust
127      auto grandparent_tx_1 = make_ephemeral_tx(random_outpoints(1), /*version=*/2);
128      const auto dust_txid = grandparent_tx_1->GetHash();
129  
130      // Child transaction spending dust
131      auto dust_spend = make_tx({COutPoint{dust_txid, EPHEMERAL_DUST_INDEX}}, /*version=*/2);
132  
133      // We first start with nothing "in the mempool", using package checks
134  
135      // Trivial single transaction with no dust
136      BOOST_CHECK(CheckEphemeralSpends({dust_spend}, dustrelay, pool, child_state, child_wtxid));
137      BOOST_CHECK(child_state.IsValid());
138      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
139  
140      // Now with dust, ok because the tx has no dusty parents
141      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_1}, dustrelay, pool, child_state, child_wtxid));
142      BOOST_CHECK(child_state.IsValid());
143      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
144  
145      // Dust checks pass
146      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_1, dust_spend}, CFeeRate(0), pool, child_state, child_wtxid));
147      BOOST_CHECK(child_state.IsValid());
148      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
149      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_1, dust_spend}, dustrelay, pool, child_state, child_wtxid));
150      BOOST_CHECK(child_state.IsValid());
151      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
152  
153      auto dust_non_spend = make_tx({COutPoint{dust_txid, EPHEMERAL_DUST_INDEX - 1}}, /*version=*/2);
154  
155      // Child spending non-dust only from parent should be disallowed even if dust otherwise spent
156      const auto dust_non_spend_wtxid{dust_non_spend->GetWitnessHash()};
157      BOOST_CHECK(!CheckEphemeralSpends({grandparent_tx_1, dust_non_spend, dust_spend}, dustrelay, pool, child_state, child_wtxid));
158      BOOST_CHECK(!child_state.IsValid());
159      BOOST_CHECK_EQUAL(child_wtxid, dust_non_spend_wtxid);
160      child_state = TxValidationState();
161      child_wtxid = Wtxid();
162  
163      BOOST_CHECK(!CheckEphemeralSpends({grandparent_tx_1, dust_spend, dust_non_spend}, dustrelay, pool, child_state, child_wtxid));
164      BOOST_CHECK(!child_state.IsValid());
165      BOOST_CHECK_EQUAL(child_wtxid, dust_non_spend_wtxid);
166      child_state = TxValidationState();
167      child_wtxid = Wtxid();
168  
169      BOOST_CHECK(!CheckEphemeralSpends({grandparent_tx_1, dust_non_spend}, dustrelay, pool, child_state, child_wtxid));
170      BOOST_CHECK(!child_state.IsValid());
171      BOOST_CHECK_EQUAL(child_wtxid, dust_non_spend_wtxid);
172      child_state = TxValidationState();
173      child_wtxid = Wtxid();
174  
175      auto grandparent_tx_2 = make_ephemeral_tx(random_outpoints(1), /*version=*/2);
176      const auto dust_txid_2 = grandparent_tx_2->GetHash();
177  
178      // Spend dust from one but not another is ok, as long as second grandparent has no child
179      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_1, grandparent_tx_2, dust_spend}, dustrelay, pool, child_state, child_wtxid));
180      BOOST_CHECK(child_state.IsValid());
181      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
182  
183      auto dust_non_spend_both_parents = make_tx({COutPoint{dust_txid, EPHEMERAL_DUST_INDEX}, COutPoint{dust_txid_2, EPHEMERAL_DUST_INDEX - 1}}, /*version=*/2);
184      // But if we spend from the parent, it must spend dust
185      BOOST_CHECK(!CheckEphemeralSpends({grandparent_tx_1, grandparent_tx_2, dust_non_spend_both_parents}, dustrelay, pool, child_state, child_wtxid));
186      BOOST_CHECK(!child_state.IsValid());
187      BOOST_CHECK_EQUAL(child_wtxid, dust_non_spend_both_parents->GetWitnessHash());
188      child_state = TxValidationState();
189      child_wtxid = Wtxid();
190  
191      auto dust_spend_both_parents = make_tx({COutPoint{dust_txid, EPHEMERAL_DUST_INDEX}, COutPoint{dust_txid_2, EPHEMERAL_DUST_INDEX}}, /*version=*/2);
192      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_1, grandparent_tx_2, dust_spend_both_parents}, dustrelay, pool, child_state, child_wtxid));
193      BOOST_CHECK(child_state.IsValid());
194      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
195  
196      // Spending other outputs is also correct, as long as the dusty one is spent
197      const std::vector<COutPoint> all_outpoints{COutPoint(dust_txid, 0), COutPoint(dust_txid, 1), COutPoint(dust_txid, 2),
198          COutPoint(dust_txid_2, 0), COutPoint(dust_txid_2, 1), COutPoint(dust_txid_2, 2)};
199      auto dust_spend_all_outpoints = make_tx(all_outpoints, /*version=*/2);
200      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_1, grandparent_tx_2, dust_spend_all_outpoints}, dustrelay, pool, child_state, child_wtxid));
201      BOOST_CHECK(child_state.IsValid());
202      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
203  
204      // 2 grandparents with dust <- 1 dust-spending parent with dust <- child with no dust
205      auto parent_with_dust = make_ephemeral_tx({COutPoint{dust_txid, EPHEMERAL_DUST_INDEX}, COutPoint{dust_txid_2, EPHEMERAL_DUST_INDEX}}, /*version=*/2);
206      // Ok for parent to have dust
207      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_1, grandparent_tx_2, parent_with_dust}, dustrelay, pool, child_state, child_wtxid));
208      BOOST_CHECK(child_state.IsValid());
209      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
210      auto child_no_dust = make_tx({COutPoint{parent_with_dust->GetHash(), EPHEMERAL_DUST_INDEX}}, /*version=*/2);
211      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_1, grandparent_tx_2, parent_with_dust, child_no_dust}, dustrelay, pool, child_state, child_wtxid));
212      BOOST_CHECK(child_state.IsValid());
213      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
214  
215      // 2 grandparents with dust <- 1 dust-spending parent with dust <- child with dust
216      auto child_with_dust = make_ephemeral_tx({COutPoint{parent_with_dust->GetHash(), EPHEMERAL_DUST_INDEX}}, /*version=*/2);
217      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_1, grandparent_tx_2, parent_with_dust, child_with_dust}, dustrelay, pool, child_state, child_wtxid));
218      BOOST_CHECK(child_state.IsValid());
219      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
220  
221      // Tests with parents in mempool
222  
223      // Nothing in mempool, this should pass for any transaction
224      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_1}, dustrelay, pool, child_state, child_wtxid));
225      BOOST_CHECK(child_state.IsValid());
226      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
227  
228      // Add first grandparent to mempool and fetch entry
229      TryAddToMempool(pool, entry.FromTx(grandparent_tx_1));
230  
231      // Ignores ancestors that aren't direct parents
232      BOOST_CHECK(CheckEphemeralSpends({child_no_dust}, dustrelay, pool, child_state, child_wtxid));
233      BOOST_CHECK(child_state.IsValid());
234      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
235  
236      // Valid spend of dust with grandparent in mempool
237      BOOST_CHECK(CheckEphemeralSpends({parent_with_dust}, dustrelay, pool, child_state, child_wtxid));
238      BOOST_CHECK(child_state.IsValid());
239      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
240  
241      // Second grandparent in same package
242      BOOST_CHECK(CheckEphemeralSpends({parent_with_dust, grandparent_tx_2}, dustrelay, pool, child_state, child_wtxid));
243      BOOST_CHECK(child_state.IsValid());
244      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
245  
246      // Order in package doesn't matter
247      BOOST_CHECK(CheckEphemeralSpends({grandparent_tx_2, parent_with_dust}, dustrelay, pool, child_state, child_wtxid));
248      BOOST_CHECK(child_state.IsValid());
249      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
250  
251      // Add second grandparent to mempool
252      TryAddToMempool(pool, entry.FromTx(grandparent_tx_2));
253  
254      // Only spends single dust out of two direct parents
255      BOOST_CHECK(!CheckEphemeralSpends({dust_non_spend_both_parents}, dustrelay, pool, child_state, child_wtxid));
256      BOOST_CHECK(!child_state.IsValid());
257      BOOST_CHECK_EQUAL(child_wtxid, dust_non_spend_both_parents->GetWitnessHash());
258      child_state = TxValidationState();
259      child_wtxid = Wtxid();
260  
261      // Spends both parents' dust
262      BOOST_CHECK(CheckEphemeralSpends({parent_with_dust}, dustrelay, pool, child_state, child_wtxid));
263      BOOST_CHECK(child_state.IsValid());
264      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
265  
266      // Now add dusty parent to mempool
267      TryAddToMempool(pool, entry.FromTx(parent_with_dust));
268  
269      // Passes dust checks even with non-parent ancestors
270      BOOST_CHECK(CheckEphemeralSpends({child_no_dust}, dustrelay, pool, child_state, child_wtxid));
271      BOOST_CHECK(child_state.IsValid());
272      BOOST_CHECK_EQUAL(child_wtxid, Wtxid());
273  }
274  
275  BOOST_FIXTURE_TEST_CASE(version3_tests, RegTestingSetup)
276  {
277      // Test TRUC policy helper functions
278      CTxMemPool& pool = *Assert(m_node.mempool);
279      LOCK2(cs_main, pool.cs);
280      TestMemPoolEntryHelper entry;
281      std::set<Txid> empty_conflicts_set;
282      std::vector<CTxMemPoolEntry::CTxMemPoolEntryRef> empty_parents;
283  
284      auto mempool_tx_v3 = make_tx(random_outpoints(1), /*version=*/3);
285      TryAddToMempool(pool, entry.FromTx(mempool_tx_v3));
286      auto mempool_tx_v2 = make_tx(random_outpoints(1), /*version=*/2);
287      TryAddToMempool(pool, entry.FromTx(mempool_tx_v2));
288  
289      // Cannot spend from an unconfirmed TRUC transaction unless this tx is also TRUC.
290      {
291          // mempool_tx_v3
292          //      ^
293          // tx_v2_from_v3
294          auto tx_v2_from_v3 = make_tx({COutPoint{mempool_tx_v3->GetHash(), 0}}, /*version=*/2);
295          auto parents_v2_from_v3 = pool.GetParents(entry.FromTx(tx_v2_from_v3));
296          const auto expected_error_str{strprintf("non-version=3 tx %s (wtxid=%s) cannot spend from version=3 tx %s (wtxid=%s)",
297              tx_v2_from_v3->GetHash().ToString(), tx_v2_from_v3->GetWitnessHash().ToString(),
298              mempool_tx_v3->GetHash().ToString(), mempool_tx_v3->GetWitnessHash().ToString())};
299          auto result_v2_from_v3{SingleTRUCChecks(pool, tx_v2_from_v3, parents_v2_from_v3, empty_conflicts_set, GetVirtualTransactionSize(*tx_v2_from_v3))};
300          BOOST_CHECK_EQUAL(result_v2_from_v3->first, expected_error_str);
301          BOOST_CHECK_EQUAL(result_v2_from_v3->second, nullptr);
302  
303          Package package_v3_v2{mempool_tx_v3, tx_v2_from_v3};
304          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, tx_v2_from_v3, GetVirtualTransactionSize(*tx_v2_from_v3), package_v3_v2, empty_parents), expected_error_str);
305          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, tx_v2_from_v3, GetVirtualTransactionSize(*tx_v2_from_v3), {tx_v2_from_v3}, parents_v2_from_v3), expected_error_str);
306  
307          // mempool_tx_v3  mempool_tx_v2
308          //            ^    ^
309          //    tx_v2_from_v2_and_v3
310          auto tx_v2_from_v2_and_v3 = make_tx({COutPoint{mempool_tx_v3->GetHash(), 0}, COutPoint{mempool_tx_v2->GetHash(), 0}}, /*version=*/2);
311          auto parents_2_from_both{pool.GetParents(entry.FromTx(tx_v2_from_v2_and_v3))};
312          const auto expected_error_str_2{strprintf("non-version=3 tx %s (wtxid=%s) cannot spend from version=3 tx %s (wtxid=%s)",
313              tx_v2_from_v2_and_v3->GetHash().ToString(), tx_v2_from_v2_and_v3->GetWitnessHash().ToString(),
314              mempool_tx_v3->GetHash().ToString(), mempool_tx_v3->GetWitnessHash().ToString())};
315          auto result_v2_from_both{SingleTRUCChecks(pool, tx_v2_from_v2_and_v3, parents_2_from_both, empty_conflicts_set, GetVirtualTransactionSize(*tx_v2_from_v2_and_v3))};
316          BOOST_CHECK_EQUAL(result_v2_from_both->first, expected_error_str_2);
317          BOOST_CHECK_EQUAL(result_v2_from_both->second, nullptr);
318  
319          Package package_v3_v2_v2{mempool_tx_v3, mempool_tx_v2, tx_v2_from_v2_and_v3};
320          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, tx_v2_from_v2_and_v3, GetVirtualTransactionSize(*tx_v2_from_v2_and_v3), package_v3_v2_v2, empty_parents), expected_error_str_2);
321      }
322  
323      // TRUC cannot spend from an unconfirmed non-TRUC transaction.
324      {
325          // mempool_tx_v2
326          //      ^
327          // tx_v3_from_v2
328          auto tx_v3_from_v2 = make_tx({COutPoint{mempool_tx_v2->GetHash(), 0}}, /*version=*/3);
329          auto parents_v3_from_v2{pool.GetParents(entry.FromTx(tx_v3_from_v2))};
330          const auto expected_error_str{strprintf("version=3 tx %s (wtxid=%s) cannot spend from non-version=3 tx %s (wtxid=%s)",
331              tx_v3_from_v2->GetHash().ToString(), tx_v3_from_v2->GetWitnessHash().ToString(),
332              mempool_tx_v2->GetHash().ToString(), mempool_tx_v2->GetWitnessHash().ToString())};
333          auto result_v3_from_v2{SingleTRUCChecks(pool, tx_v3_from_v2, parents_v3_from_v2,  empty_conflicts_set, GetVirtualTransactionSize(*tx_v3_from_v2))};
334          BOOST_CHECK_EQUAL(result_v3_from_v2->first, expected_error_str);
335          BOOST_CHECK_EQUAL(result_v3_from_v2->second, nullptr);
336  
337          Package package_v2_v3{mempool_tx_v2, tx_v3_from_v2};
338          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, tx_v3_from_v2, GetVirtualTransactionSize(*tx_v3_from_v2), package_v2_v3, empty_parents), expected_error_str);
339          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, tx_v3_from_v2, GetVirtualTransactionSize(*tx_v3_from_v2), {tx_v3_from_v2}, parents_v3_from_v2), expected_error_str);
340  
341          // mempool_tx_v3  mempool_tx_v2
342          //            ^    ^
343          //    tx_v3_from_v2_and_v3
344          auto tx_v3_from_v2_and_v3 = make_tx({COutPoint{mempool_tx_v3->GetHash(), 0}, COutPoint{mempool_tx_v2->GetHash(), 0}}, /*version=*/3);
345          auto parents_v3_from_both{pool.GetParents(entry.FromTx(tx_v3_from_v2_and_v3))};
346          const auto expected_error_str_2{strprintf("version=3 tx %s (wtxid=%s) cannot spend from non-version=3 tx %s (wtxid=%s)",
347              tx_v3_from_v2_and_v3->GetHash().ToString(), tx_v3_from_v2_and_v3->GetWitnessHash().ToString(),
348              mempool_tx_v2->GetHash().ToString(), mempool_tx_v2->GetWitnessHash().ToString())};
349          auto result_v3_from_both{SingleTRUCChecks(pool, tx_v3_from_v2_and_v3, parents_v3_from_both, empty_conflicts_set, GetVirtualTransactionSize(*tx_v3_from_v2_and_v3))};
350          BOOST_CHECK_EQUAL(result_v3_from_both->first, expected_error_str_2);
351          BOOST_CHECK_EQUAL(result_v3_from_both->second, nullptr);
352  
353          // tx_v3_from_v2_and_v3 also violates TRUC_ANCESTOR_LIMIT.
354          const auto expected_error_str_3{strprintf("tx %s (wtxid=%s) would have too many ancestors",
355              tx_v3_from_v2_and_v3->GetHash().ToString(), tx_v3_from_v2_and_v3->GetWitnessHash().ToString())};
356          Package package_v3_v2_v3{mempool_tx_v3, mempool_tx_v2, tx_v3_from_v2_and_v3};
357          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, tx_v3_from_v2_and_v3, GetVirtualTransactionSize(*tx_v3_from_v2_and_v3), package_v3_v2_v3, empty_parents), expected_error_str_3);
358      }
359      // V3 from V3 is ok, and non-V3 from non-V3 is ok.
360      {
361          // mempool_tx_v3
362          //      ^
363          // tx_v3_from_v3
364          auto tx_v3_from_v3 = make_tx({COutPoint{mempool_tx_v3->GetHash(), 0}}, /*version=*/3);
365          auto parents_v3{pool.GetParents(entry.FromTx(tx_v3_from_v3))};
366          BOOST_CHECK(SingleTRUCChecks(pool, tx_v3_from_v3, parents_v3, empty_conflicts_set, GetVirtualTransactionSize(*tx_v3_from_v3))
367                      == std::nullopt);
368  
369          Package package_v3_v3{mempool_tx_v3, tx_v3_from_v3};
370          BOOST_CHECK(PackageTRUCChecks(pool, tx_v3_from_v3, GetVirtualTransactionSize(*tx_v3_from_v3), package_v3_v3, empty_parents) == std::nullopt);
371  
372          // mempool_tx_v2
373          //      ^
374          // tx_v2_from_v2
375          auto tx_v2_from_v2 = make_tx({COutPoint{mempool_tx_v2->GetHash(), 0}}, /*version=*/2);
376          auto parents_v2{pool.GetParents(entry.FromTx(tx_v2_from_v2))};
377          BOOST_CHECK(SingleTRUCChecks(pool, tx_v2_from_v2, parents_v2, empty_conflicts_set, GetVirtualTransactionSize(*tx_v2_from_v2))
378                      == std::nullopt);
379  
380          Package package_v2_v2{mempool_tx_v2, tx_v2_from_v2};
381          BOOST_CHECK(PackageTRUCChecks(pool, tx_v2_from_v2, GetVirtualTransactionSize(*tx_v2_from_v2), package_v2_v2, empty_parents) == std::nullopt);
382      }
383  
384      // Tx spending TRUC cannot have too many mempool ancestors
385      // Configuration where the tx has multiple direct parents.
386      {
387          Package package_multi_parents;
388          std::vector<COutPoint> mempool_outpoints;
389          mempool_outpoints.emplace_back(mempool_tx_v3->GetHash(), 0);
390          package_multi_parents.emplace_back(mempool_tx_v3);
391          for (size_t i{0}; i < 2; ++i) {
392              auto mempool_tx = make_tx(random_outpoints(i + 1), /*version=*/3);
393              TryAddToMempool(pool, entry.FromTx(mempool_tx));
394              mempool_outpoints.emplace_back(mempool_tx->GetHash(), 0);
395              package_multi_parents.emplace_back(mempool_tx);
396          }
397          auto tx_v3_multi_parent = make_tx(mempool_outpoints, /*version=*/3);
398          package_multi_parents.emplace_back(tx_v3_multi_parent);
399          auto parents{pool.GetParents(entry.FromTx(tx_v3_multi_parent))};
400          BOOST_CHECK_EQUAL(parents.size(), 3);
401          const auto expected_error_str{strprintf("tx %s (wtxid=%s) would have too many ancestors",
402              tx_v3_multi_parent->GetHash().ToString(), tx_v3_multi_parent->GetWitnessHash().ToString())};
403          auto result{SingleTRUCChecks(pool, tx_v3_multi_parent, parents, empty_conflicts_set, GetVirtualTransactionSize(*tx_v3_multi_parent))};
404          BOOST_CHECK_EQUAL(result->first, expected_error_str);
405          BOOST_CHECK_EQUAL(result->second, nullptr);
406  
407          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, tx_v3_multi_parent, GetVirtualTransactionSize(*tx_v3_multi_parent), package_multi_parents, empty_parents),
408                            expected_error_str);
409      }
410  
411      // Configuration where the tx is in a multi-generation chain.
412      {
413          Package package_multi_gen;
414          CTransactionRef middle_tx;
415          auto last_outpoint{random_outpoints(1)[0]};
416          for (size_t i{0}; i < 2; ++i) {
417              auto mempool_tx = make_tx({last_outpoint}, /*version=*/3);
418              TryAddToMempool(pool, entry.FromTx(mempool_tx));
419              last_outpoint = COutPoint{mempool_tx->GetHash(), 0};
420              package_multi_gen.emplace_back(mempool_tx);
421              if (i == 1) middle_tx = mempool_tx;
422          }
423          auto tx_v3_multi_gen = make_tx({last_outpoint}, /*version=*/3);
424          package_multi_gen.emplace_back(tx_v3_multi_gen);
425          auto parents{pool.GetParents(entry.FromTx(tx_v3_multi_gen))};
426          const auto expected_error_str{strprintf("tx %s (wtxid=%s) would have too many ancestors",
427              tx_v3_multi_gen->GetHash().ToString(), tx_v3_multi_gen->GetWitnessHash().ToString())};
428          auto result{SingleTRUCChecks(pool, tx_v3_multi_gen, parents, empty_conflicts_set, GetVirtualTransactionSize(*tx_v3_multi_gen))};
429          BOOST_CHECK_EQUAL(result->first, expected_error_str);
430          BOOST_CHECK_EQUAL(result->second, nullptr);
431  
432          // Middle tx is what triggers a failure for the grandchild:
433          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, middle_tx, GetVirtualTransactionSize(*middle_tx), package_multi_gen, empty_parents), expected_error_str);
434          BOOST_CHECK(PackageTRUCChecks(pool, tx_v3_multi_gen, GetVirtualTransactionSize(*tx_v3_multi_gen), package_multi_gen, empty_parents) == std::nullopt);
435      }
436  
437      // Tx spending TRUC cannot be too large in virtual size.
438      auto many_inputs{random_outpoints(100)};
439      many_inputs.emplace_back(mempool_tx_v3->GetHash(), 0);
440      {
441          auto tx_v3_child_big = make_tx(many_inputs, /*version=*/3);
442          const auto vsize{GetVirtualTransactionSize(*tx_v3_child_big)};
443          auto parents{pool.GetParents(entry.FromTx(tx_v3_child_big))};
444          const auto expected_error_str{strprintf("version=3 child tx %s (wtxid=%s) is too big: %u > %u virtual bytes",
445              tx_v3_child_big->GetHash().ToString(), tx_v3_child_big->GetWitnessHash().ToString(), vsize, TRUC_CHILD_MAX_VSIZE)};
446          auto result{SingleTRUCChecks(pool, tx_v3_child_big, parents, empty_conflicts_set, GetVirtualTransactionSize(*tx_v3_child_big))};
447          BOOST_CHECK_EQUAL(result->first, expected_error_str);
448          BOOST_CHECK_EQUAL(result->second, nullptr);
449  
450          Package package_child_big{mempool_tx_v3, tx_v3_child_big};
451          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, tx_v3_child_big, GetVirtualTransactionSize(*tx_v3_child_big), package_child_big, empty_parents),
452                            expected_error_str);
453      }
454  
455      // Tx spending TRUC cannot have too many sigops.
456      // This child has 10 P2WSH multisig inputs.
457      auto multisig_outpoints{random_outpoints(10)};
458      multisig_outpoints.emplace_back(mempool_tx_v3->GetHash(), 0);
459      auto keys{random_keys(2)};
460      CScript script_multisig;
461      script_multisig << OP_1;
462      for (const auto& key : keys) {
463          script_multisig << ToByteVector(key);
464      }
465      script_multisig << OP_2 << OP_CHECKMULTISIG;
466      {
467          CMutableTransaction mtx_many_sigops = CMutableTransaction{};
468          mtx_many_sigops.version = TRUC_VERSION;
469          for (const auto& outpoint : multisig_outpoints) {
470              mtx_many_sigops.vin.emplace_back(outpoint);
471              mtx_many_sigops.vin.back().scriptWitness.stack.emplace_back(script_multisig.begin(), script_multisig.end());
472          }
473          mtx_many_sigops.vout.resize(1);
474          mtx_many_sigops.vout.back().scriptPubKey = CScript() << OP_TRUE;
475          mtx_many_sigops.vout.back().nValue = 10000;
476          auto tx_many_sigops{MakeTransactionRef(mtx_many_sigops)};
477  
478          auto parents{pool.GetParents(entry.FromTx(tx_many_sigops))};
479          // legacy uses fAccurate = false, and the maximum number of multisig keys is used
480          const int64_t total_sigops{static_cast<int64_t>(tx_many_sigops->vin.size()) * static_cast<int64_t>(script_multisig.GetSigOpCount(/*fAccurate=*/false))};
481          BOOST_CHECK_EQUAL(total_sigops, tx_many_sigops->vin.size() * MAX_PUBKEYS_PER_MULTISIG);
482          const int64_t bip141_vsize{GetVirtualTransactionSize(*tx_many_sigops)};
483          // Weight limit is not reached...
484          BOOST_CHECK(SingleTRUCChecks(pool, tx_many_sigops, parents, empty_conflicts_set, bip141_vsize) == std::nullopt);
485          // ...but sigop limit is.
486          const auto expected_error_str{strprintf("version=3 child tx %s (wtxid=%s) is too big: %u > %u virtual bytes",
487              tx_many_sigops->GetHash().ToString(), tx_many_sigops->GetWitnessHash().ToString(),
488              total_sigops * DEFAULT_BYTES_PER_SIGOP / WITNESS_SCALE_FACTOR, TRUC_CHILD_MAX_VSIZE)};
489          auto result{SingleTRUCChecks(pool, tx_many_sigops, parents, empty_conflicts_set,
490                                          GetVirtualTransactionSize(*tx_many_sigops, /*nSigOpCost=*/total_sigops, /*bytes_per_sigop=*/ DEFAULT_BYTES_PER_SIGOP))};
491          BOOST_CHECK_EQUAL(result->first, expected_error_str);
492          BOOST_CHECK_EQUAL(result->second, nullptr);
493  
494          Package package_child_sigops{mempool_tx_v3, tx_many_sigops};
495          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, tx_many_sigops, total_sigops * DEFAULT_BYTES_PER_SIGOP / WITNESS_SCALE_FACTOR, package_child_sigops, empty_parents),
496                            expected_error_str);
497      }
498  
499      // Parent + child with TRUC in the mempool. Child is allowed as long as it is under TRUC_CHILD_MAX_VSIZE.
500      auto tx_mempool_v3_child = make_tx({COutPoint{mempool_tx_v3->GetHash(), 0}}, /*version=*/3);
501      {
502          BOOST_CHECK(GetTransactionWeight(*tx_mempool_v3_child) <= TRUC_CHILD_MAX_VSIZE * WITNESS_SCALE_FACTOR);
503          auto parents{pool.GetParents(entry.FromTx(tx_mempool_v3_child))};
504          BOOST_CHECK(SingleTRUCChecks(pool, tx_mempool_v3_child, parents, empty_conflicts_set, GetVirtualTransactionSize(*tx_mempool_v3_child)) == std::nullopt);
505          TryAddToMempool(pool, entry.FromTx(tx_mempool_v3_child));
506  
507          Package package_v3_1p1c{mempool_tx_v3, tx_mempool_v3_child};
508          BOOST_CHECK(PackageTRUCChecks(pool, tx_mempool_v3_child, GetVirtualTransactionSize(*tx_mempool_v3_child), package_v3_1p1c, empty_parents) == std::nullopt);
509      }
510  
511      // A TRUC transaction cannot have more than 1 descendant. Sibling is returned when exactly 1 exists.
512      {
513          auto tx_v3_child2 = make_tx({COutPoint{mempool_tx_v3->GetHash(), 1}}, /*version=*/3);
514          // Configuration where parent already has 1 other child in mempool
515          auto parents_1sibling{pool.GetParents(entry.FromTx(tx_v3_child2))};
516          const auto expected_error_str{strprintf("tx %s (wtxid=%s) would exceed descendant count limit",
517              mempool_tx_v3->GetHash().ToString(), mempool_tx_v3->GetWitnessHash().ToString())};
518          auto result_with_sibling_eviction{SingleTRUCChecks(pool, tx_v3_child2, parents_1sibling, empty_conflicts_set, GetVirtualTransactionSize(*tx_v3_child2))};
519          BOOST_CHECK_EQUAL(result_with_sibling_eviction->first, expected_error_str);
520          // The other mempool child is returned to allow for sibling eviction.
521          BOOST_CHECK_EQUAL(result_with_sibling_eviction->second, tx_mempool_v3_child);
522  
523          // If directly replacing the child, make sure there is no double-counting.
524          BOOST_CHECK(SingleTRUCChecks(pool, tx_v3_child2, parents_1sibling, {tx_mempool_v3_child->GetHash()}, GetVirtualTransactionSize(*tx_v3_child2))
525                      == std::nullopt);
526  
527          Package package_v3_1p2c{mempool_tx_v3, tx_mempool_v3_child, tx_v3_child2};
528          BOOST_CHECK_EQUAL(*PackageTRUCChecks(pool, tx_v3_child2, GetVirtualTransactionSize(*tx_v3_child2), package_v3_1p2c, empty_parents),
529                            expected_error_str);
530  
531          // Configuration where parent already has 2 other children in mempool (no sibling eviction allowed). This may happen as the result of a reorg.
532          TryAddToMempool(pool, entry.FromTx(tx_v3_child2));
533          auto tx_v3_child3 = make_tx({COutPoint{mempool_tx_v3->GetHash(), 24}}, /*version=*/3);
534          auto entry_mempool_parent = pool.GetIter(mempool_tx_v3->GetHash()).value();
535          BOOST_CHECK_EQUAL(pool.GetDescendantCount(entry_mempool_parent), 3);
536          auto parents_2siblings{pool.GetParents(entry.FromTx(tx_v3_child3))};
537  
538          auto result_2children{SingleTRUCChecks(pool, tx_v3_child3, parents_2siblings, empty_conflicts_set, GetVirtualTransactionSize(*tx_v3_child3))};
539          BOOST_CHECK_EQUAL(result_2children->first, expected_error_str);
540          // The other mempool child is not returned because sibling eviction is not allowed.
541          BOOST_CHECK_EQUAL(result_2children->second, nullptr);
542      }
543  
544      // Sibling eviction: parent already has 1 other child, which also has its own child (no sibling eviction allowed). This may happen as the result of a reorg.
545      {
546          auto tx_mempool_grandparent = make_tx(random_outpoints(1), /*version=*/3);
547          auto tx_mempool_sibling = make_tx({COutPoint{tx_mempool_grandparent->GetHash(), 0}}, /*version=*/3);
548          auto tx_mempool_nibling = make_tx({COutPoint{tx_mempool_sibling->GetHash(), 0}}, /*version=*/3);
549          auto tx_to_submit = make_tx({COutPoint{tx_mempool_grandparent->GetHash(), 1}}, /*version=*/3);
550  
551          TryAddToMempool(pool, entry.FromTx(tx_mempool_grandparent));
552          TryAddToMempool(pool, entry.FromTx(tx_mempool_sibling));
553          TryAddToMempool(pool, entry.FromTx(tx_mempool_nibling));
554  
555          auto parents_3gen{pool.GetParents(entry.FromTx(tx_to_submit))};
556          const auto expected_error_str{strprintf("tx %s (wtxid=%s) would exceed descendant count limit",
557              tx_mempool_grandparent->GetHash().ToString(), tx_mempool_grandparent->GetWitnessHash().ToString())};
558          auto result_3gen{SingleTRUCChecks(pool, tx_to_submit, parents_3gen, empty_conflicts_set, GetVirtualTransactionSize(*tx_to_submit))};
559          BOOST_CHECK_EQUAL(result_3gen->first, expected_error_str);
560          // The other mempool child is not returned because sibling eviction is not allowed.
561          BOOST_CHECK_EQUAL(result_3gen->second, nullptr);
562      }
563  
564      // Configuration where tx has multiple generations of descendants is not tested because that is
565      // equivalent to the tx with multiple generations of ancestors.
566  }
567  
568  BOOST_AUTO_TEST_SUITE_END()