Rate-limit client connection attempts

This commit is contained in:
sfan5 2024-01-05 15:12:20 +01:00
parent 050152eb90
commit b2f0a37b18
2 changed files with 32 additions and 1 deletions

@ -44,6 +44,8 @@ namespace con
// TODO: Clean this up. // TODO: Clean this up.
#define LOG(a) a #define LOG(a) a
#define MAX_NEW_PEERS_PER_SEC 30
static inline session_t readPeerId(const u8 *packetdata) static inline session_t readPeerId(const u8 *packetdata)
{ {
return readU16(&packetdata[4]); return readU16(&packetdata[4]);
@ -971,9 +973,21 @@ void ConnectionReceiveThread::receive(SharedBuffer<u8> &packetdata,
// Someone new is trying to talk to us. Add them. // Someone new is trying to talk to us. Add them.
if (peer_id == PEER_ID_INEXISTENT) { if (peer_id == PEER_ID_INEXISTENT) {
auto &l = m_new_peer_ratelimit;
l.tick();
if (++l.counter > MAX_NEW_PEERS_PER_SEC) {
if (!l.logged) {
warningstream << m_connection->getDesc()
<< "Receive(): More than " << MAX_NEW_PEERS_PER_SEC
<< " new clients within 1s. Throttling." << std::endl;
}
l.logged = true;
// We simply drop the packet, the client can try again.
} else {
peer_id = m_connection->createPeer(sender, MTP_MINETEST_RELIABLE_UDP, 0); peer_id = m_connection->createPeer(sender, MTP_MINETEST_RELIABLE_UDP, 0);
} }
} }
}
PeerHelper peer = m_connection->getPeerNoEx(peer_id); PeerHelper peer = m_connection->getPeerNoEx(peer_id);
if (!peer) { if (!peer) {

@ -162,8 +162,25 @@ private:
bool reliable); bool reliable);
}; };
struct RateLimitHelper {
u64 time = 0;
int counter = 0;
bool logged = false;
void tick() {
u64 now = porting::getTimeS();
if (time != now) {
time = now;
counter = 0;
logged = false;
}
}
};
static const PacketTypeHandler packetTypeRouter[PACKET_TYPE_MAX]; static const PacketTypeHandler packetTypeRouter[PACKET_TYPE_MAX];
Connection *m_connection = nullptr; Connection *m_connection = nullptr;
RateLimitHelper m_new_peer_ratelimit;
}; };
} }