diff options
Diffstat (limited to 'src/net_processing.cpp')
| -rw-r--r-- | src/net_processing.cpp | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/src/net_processing.cpp b/src/net_processing.cpp index fd96cdfa97..ac4551faa7 100644 --- a/src/net_processing.cpp +++ b/src/net_processing.cpp @@ -1410,7 +1410,23 @@ void RelayTransaction(const uint256& txid, const uint256& wtxid, const CConnman& }); } -static void RelayAddress(const CAddress& addr, bool fReachable, const CConnman& connman) +/** + * Relay (gossip) an address to a few randomly chosen nodes. + * We choose the same nodes within a given 24h window (if the list of connected + * nodes does not change) and we don't relay to nodes that already know an + * address. So within 24h we will likely relay a given address once. This is to + * prevent a peer from unjustly giving their address better propagation by sending + * it to us repeatedly. + * @param[in] originator The peer that sent us the address. We don't want to relay it back. + * @param[in] addr Address to relay. + * @param[in] fReachable Whether the address' network is reachable. We relay unreachable + * addresses less. + * @param[in] connman Connection manager to choose nodes to relay to. + */ +static void RelayAddress(const CNode& originator, + const CAddress& addr, + bool fReachable, + const CConnman& connman) { if (!fReachable && !addr.IsRelayable()) return; @@ -1427,8 +1443,8 @@ static void RelayAddress(const CAddress& addr, bool fReachable, const CConnman& std::array<std::pair<uint64_t, CNode*>,2> best{{{0, nullptr}, {0, nullptr}}}; assert(nRelayNodes <= best.size()); - auto sortfunc = [&best, &hasher, nRelayNodes](CNode* pnode) { - if (pnode->RelayAddrsWithConn()) { + auto sortfunc = [&best, &hasher, nRelayNodes, &originator](CNode* pnode) { + if (pnode->RelayAddrsWithConn() && pnode != &originator) { uint64_t hashKey = CSipHasher(hasher).Write(pnode->GetId()).Finalize(); for (unsigned int i = 0; i < nRelayNodes; i++) { if (hashKey > best[i].first) { @@ -2570,7 +2586,7 @@ void PeerManager::ProcessMessage(CNode& pfrom, const std::string& msg_type, CDat if (addr.nTime > nSince && !pfrom.fGetAddr && vAddr.size() <= 10 && addr.IsRoutable()) { // Relay to a limited number of other nodes - RelayAddress(addr, fReachable, m_connman); + RelayAddress(pfrom, addr, fReachable, m_connman); } // Do not store addresses outside our network if (fReachable) |