更改目录结构

server/pkg/arpdis/addr.go

@@ -0,0 +1,99 @@
+package arpdis
+
+import (
+	"net"
+	"sync"
+	"time"
+)
+
+const (
+	StaleTimeNormal      = time.Minute * 5
+	StaleTimeUnreachable = time.Minute * 10
+
+	TypeNormal      = 0
+	TypeUnreachable = 1
+	TypeStatic      = 2
+)
+
+var (
+	table   = make(map[string]*Addr)
+	tableMu sync.RWMutex
+)
+
+type Addr struct {
+	IP           net.IP
+	HardwareAddr net.HardwareAddr
+	disTime      time.Time
+	Type         int8
+}
+
+func Lookup(ip net.IP, onlyTable bool) *Addr {
+	addr := tableLookup(ip.To4())
+	if addr != nil || onlyTable {
+		return addr
+	}
+
+	addr = doLookup(ip.To4())
+	Add(addr)
+	return addr
+}
+
+// Add adds a IP-MAC map to a runtime ARP table.
+func tableLookup(ip net.IP) *Addr {
+	tableMu.Lock()
+	addr := table[ip.To4().String()]
+	tableMu.Unlock()
+	if addr == nil {
+		return nil
+	}
+
+	// 判断老化过期时间
+	tsub := time.Since(addr.disTime)
+	switch addr.Type {
+	case TypeNormal:
+		if tsub > StaleTimeNormal {
+			return nil
+		}
+	case TypeUnreachable:
+		if tsub > StaleTimeUnreachable {
+			return nil
+		}
+	case TypeStatic:
+	}
+
+	return addr
+}
+
+// Add adds a IP-MAC map to a runtime ARP table.
+func Add(addr *Addr) {
+	if addr == nil {
+		return
+	}
+	if addr.disTime.IsZero() {
+		addr.disTime = time.Now()
+	}
+	ip := addr.IP.To4().String()
+	tableMu.Lock()
+	defer tableMu.Unlock()
+	if a, ok := table[ip]; ok {
+		// 静态地址只能设置一次
+		if a.Type == TypeStatic {
+			return
+		}
+	}
+	table[ip] = addr
+}
+
+// Delete removes an IP from the runtime ARP table.
+func Delete(ip net.IP) {
+	tableMu.Lock()
+	defer tableMu.Unlock()
+	delete(table, ip.To4().String())
+}
+
+// List returns the current runtime ARP table.
+func List() map[string]*Addr {
+	tableMu.RLock()
+	defer tableMu.RUnlock()
+	return table
+}