Add m_inbound_onion to AttemptToEvictConnection()

and an `m_is_onion` struct member to NodeEvictionCandidate and tests.

We'll use these in the peer eviction logic to protect inbound onion peers
in addition to the existing protection of localhost peers.

src/net.cpp

@@ -992,7 +992,8 @@ bool CConnman::AttemptToEvictConnection()
                                                node->nLastBlockTime, node->nLastTXTime,
                                                HasAllDesirableServiceFlags(node->nServices),
                                                peer_relay_txes, peer_filter_not_null, node->nKeyedNetGroup,
-                                               node->m_prefer_evict, node->addr.IsLocal()};
+                                               node->m_prefer_evict, node->addr.IsLocal(),
+                                               node->m_inbound_onion};
             vEvictionCandidates.push_back(candidate);
         }
     }

src/net.h

@@ -425,6 +425,7 @@ public:
 
     std::atomic<int64_t> nLastSend{0};
     std::atomic<int64_t> nLastRecv{0};
+    //! Unix epoch time at peer connection, in seconds.
     const int64_t nTimeConnected;
     std::atomic<int64_t> nTimeOffset{0};
     // Address of this peer
@@ -1281,6 +1282,7 @@ struct NodeEvictionCandidate
     uint64_t nKeyedNetGroup;
     bool prefer_evict;
     bool m_is_local;
+    bool m_is_onion;
 };
 
 /**

src/test/fuzz/node_eviction.cpp

@@ -31,6 +31,7 @@ FUZZ_TARGET(node_eviction)
             /* nKeyedNetGroup */ fuzzed_data_provider.ConsumeIntegral<uint64_t>(),
             /* prefer_evict */ fuzzed_data_provider.ConsumeBool(),
             /* m_is_local */ fuzzed_data_provider.ConsumeBool(),
+            /* m_is_onion */ fuzzed_data_provider.ConsumeBool(),
         });
     }
     // Make a copy since eviction_candidates may be in some valid but otherwise

src/test/net_peer_eviction_tests.cpp

@@ -36,6 +36,7 @@ std::vector<NodeEvictionCandidate> GetRandomNodeEvictionCandidates(const int n_c
             /* nKeyedNetGroup */ random_context.randrange(100),
             /* prefer_evict */ random_context.randbool(),
             /* m_is_local */ random_context.randbool(),
+            /* m_is_onion */ random_context.randbool(),
         });
     }
     return candidates;