diff --git a/server.go b/server.go index 6506c95d..c5fc4aff 100644 --- a/server.go +++ b/server.go @@ -387,11 +387,13 @@ func (sp *serverPeer) addBanScore(persistent, transient uint32, reason string) b } score := sp.banScore.Increase(persistent, transient) if score > warnThreshold { - peerLog.Warnf("Misbehaving peer %s: %s -- ban score increased to %d", - sp, reason, score) + peerLog.Warnf("Misbehaving peer %s: %s -- ban score increased to %d", sp, reason, score) if score > cfg.BanThreshold { - peerLog.Warnf("Misbehaving peer %s -- banning and disconnecting", - sp) + if sp.server.ConnectedCount() <= 1 { + peerLog.Warnf("Refusing to ban peer %s as it is the only peer", sp) + return false + } + peerLog.Warnf("Misbehaving peer %s -- banning and disconnecting", sp) sp.server.BanPeer(sp) sp.Disconnect() return true @@ -1328,24 +1330,28 @@ func (sp *serverPeer) OnNotFound(p *peer.Peer, msg *wire.MsgNotFound) { case wire.InvTypeWitnessTx: numTxns++ default: - peerLog.Debugf("Invalid inv type '%d' in notfound message from %s", - inv.Type, sp) + peerLog.Infof("Invalid inv type '%d' in NotFound message from %s. Disconnecting...", inv.Type, sp) sp.Disconnect() return } } if numBlocks > 0 { blockStr := pickNoun(uint64(numBlocks), "block", "blocks") - reason := fmt.Sprintf("%d %v not found", numBlocks, blockStr) - if sp.addBanScore(20*numBlocks, 0, reason) { - return + reason := fmt.Sprintf("%d %v not found on %s", numBlocks, blockStr, sp) + if sp.addBanScore(20, 0, reason) { + return // once they fail to return us five block requests they're gone for good } } if numTxns > 0 { - txStr := pickNoun(uint64(numTxns), "transaction", "transactions") - reason := fmt.Sprintf("%d %v not found", numBlocks, txStr) - if sp.addBanScore(0, 10*numTxns, reason) { - return + // This is an expected situation if transactions in the mempool make it into a block before + // this node knows about said block. We don't want to ban them for that alone + peerLog.Debugf("%d transactions not found on %s", numTxns, sp) + if numBlocks+numTxns < wire.MaxInvPerMsg { // if our message is full then it is likely followed by another one that isn't + txStr := pickNoun(uint64(numTxns), "transaction", "transactions") + reason := fmt.Sprintf("%d %v not found on %s", numTxns, txStr, sp) + if sp.addBanScore(0, 20, reason) { + return // if they fail us five times in one minute, they're gone -- hitting them at new-block should be rare + } } }