Method AddTx

src/node/txorphanage.cpp:307–353

}

bool TxOrphanageImpl::AddTx(const CTransactionRef& tx, NodeId peer)
{
    const auto& wtxid{tx->GetWitnessHash()};
    const auto& txid{tx->GetHash()};

    // Ignore transactions above max standard size to avoid a send-big-orphans memory exhaustion attack.
    TxOrphanage::Usage sz = GetTransactionWeight(*tx);
    if (sz > MAX_STANDARD_TX_WEIGHT) {
        LogDebug(BCLog::TXPACKAGES, "ignoring large orphan tx (size: %u, txid: %s, wtxid: %s)\n", sz, txid.ToString(), wtxid.ToString());
        return false;
    }

    // We will return false if the tx already exists under a different peer.
    const bool brand_new{!HaveTx(wtxid)};

    auto [iter, inserted] = m_orphans.get<ByWtxid>().emplace(tx, peer, m_current_sequence);
    // If the announcement (same wtxid, same peer) already exists, emplacement fails. Return false.
    if (!inserted) return false;

    ++m_current_sequence;
    auto& peer_info = m_peer_orphanage_info.try_emplace(peer).first->second;
    peer_info.Add(*iter);

    // Add links in m_outpoint_to_orphan_wtxids
    if (brand_new) {
        for (const auto& input : tx->vin) {
            auto& wtxids_for_prevout = m_outpoint_to_orphan_wtxids.try_emplace(input.prevout).first->second;
            wtxids_for_prevout.emplace(wtxid);
        }

        m_unique_orphans += 1;
        m_unique_orphan_usage += iter->GetMemUsage();
        m_unique_rounded_input_scores += iter->GetLatencyScore() - 1;

        LogDebug(BCLog::TXPACKAGES, "stored orphan tx %s (wtxid=%s), weight: %u (mapsz %u outsz %u)\n",
                    txid.ToString(), wtxid.ToString(), sz, m_orphans.size(), m_outpoint_to_orphan_wtxids.size());
        Assume(IsUnique(iter));
    } else {
        LogDebug(BCLog::TXPACKAGES, "added peer=%d as announcer of orphan tx %s (wtxid=%s)\n",
                    peer, txid.ToString(), wtxid.ToString());
        Assume(!IsUnique(iter));
    }

    // DoS prevention: do not allow m_orphanage to grow unbounded (see CVE-2012-3789)
    LimitOrphans();
    return brand_new;
}

bool TxOrphanageImpl::AddAnnouncer(const Wtxid& wtxid, NodeId peer)
{