first version

internal/history/history.go

@@ -0,0 +1,103 @@
+package history
+
+import (
+	"kf2-antiddos/internal/common"
+)
+
+type History struct {
+	quit      chan struct{}
+	eventChan *chan common.Event
+	banChan   *chan string
+	resetChan *chan string
+	head      byte
+	history   map[byte]common.Event
+	ips       map[string]uint // map[ip]conn_count
+	whitelist map[string]struct{}
+	banned    map[string]struct{}
+	maxConn   uint
+	workerID  uint
+}
+
+func New(workerID uint, eventChan *chan common.Event, banChan *chan string, resetChan *chan string, maxConn uint) *History {
+	return &History{
+		quit:      make(chan struct{}),
+		ips:       make(map[string]uint, 0),
+		history:   make(map[byte]common.Event, 0),
+		whitelist: make(map[string]struct{}, 0),
+		banned:    make(map[string]struct{}, 0),
+		eventChan: eventChan,
+		banChan:   banChan,
+		resetChan: resetChan,
+		head:      0,
+		maxConn:   maxConn,
+		workerID:  workerID,
+	}
+}
+
+func (h *History) Do() {
+	go func() {
+		for {
+			select {
+			case event := <-*h.eventChan:
+				h.registerEvent(event)
+			case ip := <-*h.resetChan:
+				h.resetIp(ip)
+			case <-h.quit:
+				return
+			}
+		}
+	}()
+}
+
+func (h *History) Stop() {
+	close(h.quit)
+}
+
+func (h *History) registerEvent(e common.Event) {
+	h.history[e.LineNum] = e
+
+	for {
+		nextEvent, nextEventExists := h.history[h.head+1]
+		if nextEventExists {
+			switch {
+			case nextEvent.ConnectIP != "":
+				h.registerConnect(nextEvent.ConnectIP)
+			case nextEvent.PlayerEndIP != "":
+				h.registerEndPlayer(nextEvent.PlayerEndIP)
+			case nextEvent.PlayerStartIP != "":
+				h.registerNewPlayer(nextEvent.PlayerEndIP)
+			}
+			delete(h.history, h.head+1)
+			h.head++
+		} else {
+			break
+		}
+	}
+}
+
+func (h *History) registerConnect(ip string) {
+	h.ips[ip]++
+	if h.ips[ip] > h.maxConn {
+		_, whitelisted := h.whitelist[ip]
+		_, banned := h.banned[ip]
+		if !whitelisted && !banned {
+			h.banned[ip] = struct{}{}
+			*h.banChan <- ip
+		}
+	}
+}
+
+func (h *History) registerNewPlayer(ip string) {
+	h.whitelist[ip] = struct{}{}
+}
+
+func (h *History) registerEndPlayer(ip string) {
+	delete(h.whitelist, ip)
+	delete(h.ips, ip)
+	delete(h.banned, ip)
+}
+
+func (h *History) resetIp(ip string) {
+	delete(h.ips, ip)
+	delete(h.banned, ip)
+}