diff --git a/src/net.cpp b/src/net.cpp index 9cfb9d71d..d8d2783c4 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -836,13 +836,20 @@ static bool AttemptToEvictConnection(bool fPreferNewConnection) { } // Protect connections with certain characteristics + + // Deterministically select 4 peers to protect by netgroup. + // An attacker cannot predict which netgroups will be protected. static CompareNetGroupKeyed comparerNetGroupKeyed; std::sort(vEvictionCandidates.begin(), vEvictionCandidates.end(), comparerNetGroupKeyed); vEvictionCandidates.erase(vEvictionCandidates.end() - std::min(4, static_cast(vEvictionCandidates.size())), vEvictionCandidates.end()); + // Protect the 8 nodes with the best ping times. + // An attacker cannot manipulate this metric without physically moving nodes closer to the target. std::sort(vEvictionCandidates.begin(), vEvictionCandidates.end(), ReverseCompareNodeMinPingTime); vEvictionCandidates.erase(vEvictionCandidates.end() - std::min(8, static_cast(vEvictionCandidates.size())), vEvictionCandidates.end()); + // Protect the 64 nodes which have been connected the longest. + // This replicates the existing implicit behavior. std::sort(vEvictionCandidates.begin(), vEvictionCandidates.end(), ReverseCompareNodeTimeConnected); vEvictionCandidates.erase(vEvictionCandidates.end() - std::min(64, static_cast(vEvictionCandidates.size())), vEvictionCandidates.end());