[net processing] FeeFilterRounder doesn't own a FastRandomContext

Author: dergoegge

src/net_processing.cpp

@@ -1813,7 +1813,7 @@ PeerManagerImpl::PeerManagerImpl(CConnman& connman, AddrMan& addrman,
                                  BanMan* banman, ChainstateManager& chainman,
                                  CTxMemPool& pool, Options opts)
     : m_rng{opts.deterministic_rng},
-      m_fee_filter_rounder{CFeeRate{DEFAULT_MIN_RELAY_TX_FEE}},
+      m_fee_filter_rounder{CFeeRate{DEFAULT_MIN_RELAY_TX_FEE}, m_rng},
       m_chainparams(chainman.GetParams()),
       m_connman(connman),
       m_addrman(addrman),

src/policy/fees.cpp

@@ -1054,8 +1054,9 @@ static std::set<double> MakeFeeSet(const CFeeRate& min_incremental_fee,
     return fee_set;
 }
 
-FeeFilterRounder::FeeFilterRounder(const CFeeRate& minIncrementalFee)
-    : m_fee_set{MakeFeeSet(minIncrementalFee, MAX_FILTER_FEERATE, FEE_FILTER_SPACING)}
+FeeFilterRounder::FeeFilterRounder(const CFeeRate& minIncrementalFee, FastRandomContext& rng)
+    : m_fee_set{MakeFeeSet(minIncrementalFee, MAX_FILTER_FEERATE, FEE_FILTER_SPACING)},
+      insecure_rand{rng}
 {
 }
 

src/policy/fees.h

@@ -320,15 +320,15 @@ class FeeFilterRounder
 
 public:
     /** Create new FeeFilterRounder */
-    explicit FeeFilterRounder(const CFeeRate& min_incremental_fee);
+    explicit FeeFilterRounder(const CFeeRate& min_incremental_fee, FastRandomContext& rng);
 
     /** Quantize a minimum fee for privacy purpose before broadcast. */
     CAmount round(CAmount currentMinFee) EXCLUSIVE_LOCKS_REQUIRED(!m_insecure_rand_mutex);
 
 private:
     const std::set<double> m_fee_set;
     Mutex m_insecure_rand_mutex;
-    FastRandomContext insecure_rand GUARDED_BY(m_insecure_rand_mutex);
+    FastRandomContext& insecure_rand GUARDED_BY(m_insecure_rand_mutex);
 };
 
 #endif // BITCOIN_POLICY_FEES_H

src/test/fuzz/fees.cpp

@@ -17,7 +17,8 @@ FUZZ_TARGET(fees)
 {
     FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
     const CFeeRate minimal_incremental_fee{ConsumeMoney(fuzzed_data_provider)};
-    FeeFilterRounder fee_filter_rounder{minimal_incremental_fee};
+    FastRandomContext rng{/*fDeterministic=*/true};
+    FeeFilterRounder fee_filter_rounder{minimal_incremental_fee, rng};
     LIMITED_WHILE(fuzzed_data_provider.ConsumeBool(), 10000) {
         const CAmount current_minimum_fee = ConsumeMoney(fuzzed_data_provider);
         const CAmount rounded_fee = fee_filter_rounder.round(current_minimum_fee);

src/test/policy_fee_tests.cpp

@@ -13,7 +13,8 @@ BOOST_AUTO_TEST_SUITE(policy_fee_tests)
 
 BOOST_AUTO_TEST_CASE(FeeRounder)
 {
-    FeeFilterRounder fee_rounder{CFeeRate{1000}};
+    FastRandomContext rng{/*fDeterministic=*/true};
+    FeeFilterRounder fee_rounder{CFeeRate{1000}, rng};
 
     // check that 1000 rounds to 974 or 1071
     std::set<CAmount> results;