remove redunant code and cleanup (#1970)

* remove redundant code

* check invalid ip address first

* remove redundant code

* cleanup

Co-authored-by: 刘海洋 <haiyang@snqu.com>

util/addr/addr.go

@@ -10,11 +10,14 @@ var (
 )
 
 func init() {
-	for _, b := range []string{"10.0.0.0/8", "172.16.0.0/12", "192.168.0.0/16", "100.64.0.0/10", "fd00::/8"} {
+	blocks := []string{
-		if _, block, err := net.ParseCIDR(b); err == nil {
+		"10.0.0.0/8",
-			privateBlocks = append(privateBlocks, block)
+		"172.16.0.0/12",
-		}
+		"192.168.0.0/16",
+		"100.64.0.0/10",
+		"fd00::/8",
 	}
+	AppendPrivateBlocks(blocks...)
 }
 
 // AppendPrivateBlocks append private network blocks
@@ -28,14 +31,53 @@ func AppendPrivateBlocks(bs ...string) {
 
 func isPrivateIP(ipAddr string) bool {
 	ip := net.ParseIP(ipAddr)
-	for _, priv := range privateBlocks {
+	if ip == nil {
-		if priv.Contains(ip) {
+		return false
+	}
+
+	for _, blocks := range privateBlocks {
+		if blocks.Contains(ip) {
 			return true
 		}
 	}
 	return false
 }
 
+func addrToIP(addr net.Addr) net.IP {
+	switch v := addr.(type) {
+	case *net.IPAddr:
+		return v.IP
+	case *net.IPNet:
+		return v.IP
+	default:
+		return nil
+	}
+}
+
+func localIPs() []string {
+	ifaces, err := net.Interfaces()
+	if err != nil {
+		return nil
+	}
+
+	var ipAddrs []string
+
+	for _, iface := range ifaces {
+		addrs, err := iface.Addrs()
+		if err != nil {
+			continue // ignore error
+		}
+
+		for _, addr := range addrs {
+			if ip := addrToIP(addr); ip != nil {
+				ipAddrs = append(ipAddrs, ip.String())
+			}
+		}
+	}
+
+	return ipAddrs
+}
+
 // IsLocal tells us whether an ip is local
 func IsLocal(addr string) bool {
 	// extract the host
@@ -50,7 +92,7 @@ func IsLocal(addr string) bool {
 	}
 
 	// check against all local ips
-	for _, ip := range IPs() {
+	for _, ip := range localIPs() {
 		if addr == ip {
 			return true
 		}
@@ -62,71 +104,41 @@ func IsLocal(addr string) bool {
 // Extract returns a real ip
 func Extract(addr string) (string, error) {
 	// if addr specified then its returned
-	if len(addr) > 0 && (addr != "0.0.0.0" && addr != "[::]" && addr != "::") {
+	if len(addr) > 0 {
+		if addr != "0.0.0.0" && addr != "[::]" && addr != "::" {
 			return addr, nil
 		}
-
-	ifaces, err := net.Interfaces()
-	if err != nil {
-		return "", fmt.Errorf("Failed to get interfaces! Err: %v", err)
 	}
 
-	//nolint:prealloc
+	var privateAddrs []string
-	var addrs []net.Addr
+	var publicAddrs []string
-	var loAddrs []net.Addr
+	var loopbackAddrs []string
-	for _, iface := range ifaces {
-		ifaceAddrs, err := iface.Addrs()
-		if err != nil {
-			// ignore error, interface can disappear from system
-			continue
-		}
-		if iface.Flags&net.FlagLoopback != 0 {
-			loAddrs = append(loAddrs, ifaceAddrs...)
-			continue
-		}
-		addrs = append(addrs, ifaceAddrs...)
-	}
-	addrs = append(addrs, loAddrs...)
 
-	var ipAddr string
+	for _, ipAddr := range localIPs() {
-	var publicIP string
+		ip := net.ParseIP(ipAddr)
-
+		if ip == nil {
-	for _, rawAddr := range addrs {
-		var ip net.IP
-		switch addr := rawAddr.(type) {
-		case *net.IPAddr:
-			ip = addr.IP
-		case *net.IPNet:
-			ip = addr.IP
-		default:
 			continue
 		}
 
-		if !isPrivateIP(ip.String()) {
+		if ip.IsUnspecified() {
-			publicIP = ip.String()
 			continue
 		}
 
-		ipAddr = ip.String()
+		if ip.IsLoopback() {
-		break
+			loopbackAddrs = append(loopbackAddrs, ipAddr)
+		} else if isPrivateIP(ipAddr) {
+			privateAddrs = append(privateAddrs, ipAddr)
+		} else {
+			publicAddrs = append(publicAddrs, ipAddr)
+		}
 	}
 
-	// return private ip
+	if len(privateAddrs) > 0 {
-	if len(ipAddr) > 0 {
+		return privateAddrs[0], nil
-		a := net.ParseIP(ipAddr)
+	} else if len(publicAddrs) > 0 {
-		if a == nil {
+		return publicAddrs[0], nil
-			return "", fmt.Errorf("ip addr %s is invalid", ipAddr)
+	} else if len(loopbackAddrs) > 0 {
-		}
+		return loopbackAddrs[0], nil
-		return a.String(), nil
-	}
-
-	// return public or virtual ip
-	if len(publicIP) > 0 {
-		a := net.ParseIP(publicIP)
-		if a == nil {
-			return "", fmt.Errorf("ip addr %s is invalid", publicIP)
-		}
-		return a.String(), nil
 	}
 
 	return "", fmt.Errorf("No IP address found, and explicit IP not provided")
@@ -134,43 +146,5 @@ func Extract(addr string) (string, error) {
 
 // IPs returns all known ips
 func IPs() []string {
-	ifaces, err := net.Interfaces()
+	return localIPs()
-	if err != nil {
-		return nil
-	}
-
-	var ipAddrs []string
-
-	for _, i := range ifaces {
-		addrs, err := i.Addrs()
-		if err != nil {
-			continue
-		}
-
-		for _, addr := range addrs {
-			var ip net.IP
-			switch v := addr.(type) {
-			case *net.IPNet:
-				ip = v.IP
-			case *net.IPAddr:
-				ip = v.IP
-			}
-
-			if ip == nil {
-				continue
-			}
-
-			// dont skip ipv6 addrs
-			/*
-				ip = ip.To4()
-				if ip == nil {
-					continue
-				}
-			*/
-
-			ipAddrs = append(ipAddrs, ip.String())
-		}
-	}
-
-	return ipAddrs
 }