Refactor: metadata use netip.Addr

adapter/adapter.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"net"
 	"net/http"
+	"net/netip"
 	"net/url"
 	"strings"
 	"time"
@@ -64,9 +65,9 @@ func (p *Proxy) ListenPacketContext(ctx context.Context, metadata *C.Metadata, o
 
 // DelayHistory implements C.Proxy
 func (p *Proxy) DelayHistory() []C.DelayHistory {
-	queue := p.history.Copy()
+	queueM := p.history.Copy()
 	histories := []C.DelayHistory{}
-	for _, item := range queue {
+	for _, item := range queueM {
 		histories = append(histories, item)
 	}
 	return histories
@@ -95,7 +96,7 @@ func (p *Proxy) MarshalJSON() ([]byte, error) {
 	}
 
 	mapping := map[string]any{}
-	json.Unmarshal(inner, &mapping)
+	_ = json.Unmarshal(inner, &mapping)
 	mapping["history"] = p.DelayHistory()
 	mapping["name"] = p.Name()
 	mapping["udp"] = p.SupportUDP()
@@ -129,7 +130,9 @@ func (p *Proxy) URLTest(ctx context.Context, url string) (t uint16, err error) {
 	if err != nil {
 		return
 	}
-	defer instance.Close()
+	defer func() {
+		_ = instance.Close()
+	}()
 
 	req, err := http.NewRequest(http.MethodHead, url, nil)
 	if err != nil {
@@ -138,7 +141,7 @@ func (p *Proxy) URLTest(ctx context.Context, url string) (t uint16, err error) {
 	req = req.WithContext(ctx)
 
 	transport := &http.Transport{
-		Dial: func(string, string) (net.Conn, error) {
+		DialContext: func(context.Context, string, string) (net.Conn, error) {
 			return instance, nil
 		},
 		// from http.DefaultTransport
@@ -167,8 +170,7 @@ func (p *Proxy) URLTest(ctx context.Context, url string) (t uint16, err error) {
 			return
 		}
 	}
-
+	_ = resp.Body.Close()
-	resp.Body.Close()
 	t = uint16(time.Since(start) / time.Millisecond)
 	return
 }
@@ -199,7 +201,7 @@ func urlToMetadata(rawURL string) (addr C.Metadata, err error) {
 	addr = C.Metadata{
 		AddrType: C.AtypDomainName,
 		Host:     u.Hostname(),
-		DstIP:    nil,
+		DstIP:    netip.Addr{},
 		DstPort:  port,
 	}
 	return

adapter/inbound/socket.go

@@ -37,7 +37,7 @@ func NewInner(conn net.Conn, dst string, host string) *context.ConnContext {
 		metadata.DstPort = port
 		if host == "" {
 			metadata.DstIP = ip
-			if ip.To4() == nil {
+			if ip.Is4() {
 				metadata.AddrType = C.AtypIPv6
 			} else {
 				metadata.AddrType = C.AtypIPv4

adapter/inbound/util.go

@@ -3,9 +3,11 @@ package inbound
 import (
 	"net"
 	"net/http"
+	"net/netip"
 	"strconv"
 	"strings"
 
+	"github.com/Dreamacro/clash/common/nnip"
 	C "github.com/Dreamacro/clash/constant"
 	"github.com/Dreamacro/clash/transport/socks5"
 )
@@ -21,12 +23,10 @@ func parseSocksAddr(target socks5.Addr) *C.Metadata {
 		metadata.Host = strings.TrimRight(string(target[2:2+target[1]]), ".")
 		metadata.DstPort = strconv.Itoa((int(target[2+target[1]]) << 8) | int(target[2+target[1]+1]))
 	case socks5.AtypIPv4:
-		ip := net.IP(target[1 : 1+net.IPv4len])
+		metadata.DstIP = nnip.IpToAddr(net.IP(target[1 : 1+net.IPv4len]))
-		metadata.DstIP = ip
 		metadata.DstPort = strconv.Itoa((int(target[1+net.IPv4len]) << 8) | int(target[1+net.IPv4len+1]))
 	case socks5.AtypIPv6:
-		ip := net.IP(target[1 : 1+net.IPv6len])
+		metadata.DstIP = nnip.IpToAddr(net.IP(target[1 : 1+net.IPv6len]))
-		metadata.DstIP = ip
 		metadata.DstPort = strconv.Itoa((int(target[1+net.IPv6len]) << 8) | int(target[1+net.IPv6len+1]))
 	}
 
@@ -47,14 +47,14 @@ func parseHTTPAddr(request *http.Request) *C.Metadata {
 		NetWork:  C.TCP,
 		AddrType: C.AtypDomainName,
 		Host:     host,
-		DstIP:    nil,
+		DstIP:    netip.Addr{},
 		DstPort:  port,
 	}
 
-	ip := net.ParseIP(host)
+	ip, err := netip.ParseAddr(host)
-	if ip != nil {
+	if err == nil {
 		switch {
-		case ip.To4() == nil:
+		case ip.Is6():
 			metadata.AddrType = C.AtypIPv6
 		default:
 			metadata.AddrType = C.AtypIPv4
@@ -65,12 +65,12 @@ func parseHTTPAddr(request *http.Request) *C.Metadata {
 	return metadata
 }
 
-func parseAddr(addr string) (net.IP, string, error) {
+func parseAddr(addr string) (netip.Addr, string, error) {
 	host, port, err := net.SplitHostPort(addr)
 	if err != nil {
-		return nil, "", err
+		return netip.Addr{}, "", err
 	}
 
-	ip := net.ParseIP(host)
+	ip, err := netip.ParseAddr(host)
-	return ip, port, nil
+	return ip, port, err
 }

adapter/outbound/util.go

@@ -22,8 +22,8 @@ var (
 
 func tcpKeepAlive(c net.Conn) {
 	if tcp, ok := c.(*net.TCPConn); ok {
-		tcp.SetKeepAlive(true)
+		_ = tcp.SetKeepAlive(true)
-		tcp.SetKeepAlivePeriod(30 * time.Second)
+		_ = tcp.SetKeepAlivePeriod(30 * time.Second)
 	}
 }
 
@@ -48,14 +48,14 @@ func serializesSocksAddr(metadata *C.Metadata) []byte {
 	port := []byte{uint8(p >> 8), uint8(p & 0xff)}
 	switch metadata.AddrType {
 	case socks5.AtypDomainName:
-		len := uint8(len(metadata.Host))
+		lenM := uint8(len(metadata.Host))
 		host := []byte(metadata.Host)
-		buf = [][]byte{{aType, len}, host, port}
+		buf = [][]byte{{aType, lenM}, host, port}
 	case socks5.AtypIPv4:
-		host := metadata.DstIP.To4()
+		host := metadata.DstIP.AsSlice()
 		buf = [][]byte{{aType}, host, port}
 	case socks5.AtypIPv6:
-		host := metadata.DstIP.To16()
+		host := metadata.DstIP.AsSlice()
 		buf = [][]byte{{aType}, host, port}
 	}
 	return bytes.Join(buf, nil)
@@ -76,6 +76,6 @@ func resolveUDPAddr(network, address string) (*net.UDPAddr, error) {
 
 func safeConnClose(c net.Conn, err error) {
 	if err != nil {
-		c.Close()
+		_ = c.Close()
 	}
 }

adapter/outbound/vless.go

@@ -259,11 +259,11 @@ func parseVlessAddr(metadata *C.Metadata) *vless.DstAddr {
 	case C.AtypIPv4:
 		addrType = byte(vless.AtypIPv4)
 		addr = make([]byte, net.IPv4len)
-		copy(addr[:], metadata.DstIP.To4())
+		copy(addr[:], metadata.DstIP.AsSlice())
 	case C.AtypIPv6:
 		addrType = byte(vless.AtypIPv6)
 		addr = make([]byte, net.IPv6len)
-		copy(addr[:], metadata.DstIP.To16())
+		copy(addr[:], metadata.DstIP.AsSlice())
 	case C.AtypDomainName:
 		addrType = byte(vless.AtypDomainName)
 		addr = make([]byte, len(metadata.Host)+1)

adapter/outbound/vmess.go

@@ -342,11 +342,11 @@ func parseVmessAddr(metadata *C.Metadata) *vmess.DstAddr {
 	case C.AtypIPv4:
 		addrType = byte(vmess.AtypIPv4)
 		addr = make([]byte, net.IPv4len)
-		copy(addr[:], metadata.DstIP.To4())
+		copy(addr[:], metadata.DstIP.AsSlice())
 	case C.AtypIPv6:
 		addrType = byte(vmess.AtypIPv6)
 		addr = make([]byte, net.IPv6len)
-		copy(addr[:], metadata.DstIP.To16())
+		copy(addr[:], metadata.DstIP.AsSlice())
 	case C.AtypDomainName:
 		addrType = byte(vmess.AtypDomainName)
 		addr = make([]byte, len(metadata.Host)+1)

adapter/outboundgroup/loadbalance.go

@@ -51,7 +51,7 @@ func getKey(metadata *C.Metadata) string {
 		}
 	}
 
-	if metadata.DstIP == nil {
+	if !metadata.DstIP.IsValid() {
 		return ""
 	}
 

adapter/outboundgroup/util.go

@@ -3,6 +3,7 @@ package outboundgroup
 import (
 	"fmt"
 	"net"
+	"net/netip"
 	"time"
 
 	C "github.com/Dreamacro/clash/constant"
@@ -15,20 +16,20 @@ func addrToMetadata(rawAddress string) (addr *C.Metadata, err error) {
 		return
 	}
 
-	ip := net.ParseIP(host)
+	ip, err := netip.ParseAddr(host)
-	if ip == nil {
+	if err != nil {
 		addr = &C.Metadata{
 			AddrType: C.AtypDomainName,
 			Host:     host,
-			DstIP:    nil,
+			DstIP:    netip.Addr{},
 			DstPort:  port,
 		}
 		return
-	} else if ip4 := ip.To4(); ip4 != nil {
+	} else if ip.Is4() {
 		addr = &C.Metadata{
 			AddrType: C.AtypIPv4,
 			Host:     "",
-			DstIP:    ip4,
+			DstIP:    ip,
 			DstPort:  port,
 		}
 		return
@@ -45,7 +46,7 @@ func addrToMetadata(rawAddress string) (addr *C.Metadata, err error) {
 
 func tcpKeepAlive(c net.Conn) {
 	if tcp, ok := c.(*net.TCPConn); ok {
-		tcp.SetKeepAlive(true)
+		_ = tcp.SetKeepAlive(true)
-		tcp.SetKeepAlivePeriod(30 * time.Second)
+		_ = tcp.SetKeepAlivePeriod(30 * time.Second)
 	}
 }

component/dhcp/dhcp.go

@@ -4,7 +4,9 @@ import (
 	"context"
 	"errors"
 	"net"
+	"net/netip"
 
+	"github.com/Dreamacro/clash/common/nnip"
 	"github.com/Dreamacro/clash/component/iface"
 
 	"github.com/insomniacslk/dhcp/dhcpv4"
@@ -15,14 +17,16 @@ var (
 	ErrNotFound      = errors.New("DNS option not found")
 )
 
-func ResolveDNSFromDHCP(context context.Context, ifaceName string) ([]net.IP, error) {
+func ResolveDNSFromDHCP(context context.Context, ifaceName string) ([]netip.Addr, error) {
 	conn, err := ListenDHCPClient(context, ifaceName)
 	if err != nil {
 		return nil, err
 	}
-	defer conn.Close()
+	defer func() {
+		_ = conn.Close()
+	}()
 
-	result := make(chan []net.IP, 1)
+	result := make(chan []netip.Addr, 1)
 
 	ifaceObj, err := iface.ResolveInterface(ifaceName)
 	if err != nil {
@@ -52,7 +56,7 @@ func ResolveDNSFromDHCP(context context.Context, ifaceName string) ([]net.IP, er
 	}
 }
 
-func receiveOffer(conn net.PacketConn, id dhcpv4.TransactionID, result chan<- []net.IP) {
+func receiveOffer(conn net.PacketConn, id dhcpv4.TransactionID, result chan<- []netip.Addr) {
 	defer close(result)
 
 	buf := make([]byte, dhcpv4.MaxMessageSize)
@@ -77,11 +81,17 @@ func receiveOffer(conn net.PacketConn, id dhcpv4.TransactionID, result chan<- []
 		}
 
 		dns := pkt.DNS()
-		if len(dns) == 0 {
+		l := len(dns)
+		if l == 0 {
 			return
 		}
 
-		result <- dns
+		dnsAddr := make([]netip.Addr, l)
+		for i := 0; i < l; i++ {
+			dnsAddr[i] = nnip.IpToAddr(dns[i])
+		}
+
+		result <- dnsAddr
 
 		return
 	}

component/dialer/bind_darwin.go

@@ -2,6 +2,7 @@ package dialer
 
 import (
 	"net"
+	"net/netip"
 	"syscall"
 
 	"github.com/Dreamacro/clash/component/iface"
@@ -19,13 +20,10 @@ func bindControl(ifaceIdx int, chain controlFn) controlFn {
 			}
 		}()
 
-		ipStr, _, err := net.SplitHostPort(address)
+		addrPort, err := netip.ParseAddrPort(address)
-		if err == nil {
+		if err == nil && !addrPort.Addr().IsGlobalUnicast() {
-			ip := net.ParseIP(ipStr)
-			if ip != nil && !ip.IsGlobalUnicast() {
 			return
 		}
-		}
 
 		var innerErr error
 		err = c.Control(func(fd uintptr) {
@@ -45,7 +43,7 @@ func bindControl(ifaceIdx int, chain controlFn) controlFn {
 	}
 }
 
-func bindIfaceToDialer(ifaceName string, dialer *net.Dialer, _ string, _ net.IP) error {
+func bindIfaceToDialer(ifaceName string, dialer *net.Dialer, _ string, _ netip.Addr) error {
 	ifaceObj, err := iface.ResolveInterface(ifaceName)
 	if err != nil {
 		return err

component/dialer/bind_linux.go

@@ -2,6 +2,7 @@ package dialer
 
 import (
 	"net"
+	"net/netip"
 	"syscall"
 
 	"golang.org/x/sys/unix"
@@ -17,13 +18,10 @@ func bindControl(ifaceName string, chain controlFn) controlFn {
 			}
 		}()
 
-		ipStr, _, err := net.SplitHostPort(address)
+		addrPort, err := netip.ParseAddrPort(address)
-		if err == nil {
+		if err == nil && !addrPort.Addr().IsGlobalUnicast() {
-			ip := net.ParseIP(ipStr)
-			if ip != nil && !ip.IsGlobalUnicast() {
 			return
 		}
-		}
 
 		var innerErr error
 		err = c.Control(func(fd uintptr) {
@@ -38,7 +36,7 @@ func bindControl(ifaceName string, chain controlFn) controlFn {
 	}
 }
 
-func bindIfaceToDialer(ifaceName string, dialer *net.Dialer, _ string, _ net.IP) error {
+func bindIfaceToDialer(ifaceName string, dialer *net.Dialer, _ string, _ netip.Addr) error {
 	dialer.Control = bindControl(ifaceName, dialer.Control)
 
 	return nil

component/dialer/bind_others.go

@@ -4,27 +4,28 @@ package dialer
 
 import (
 	"net"
+	"net/netip"
 	"strconv"
 	"strings"
 
 	"github.com/Dreamacro/clash/component/iface"
 )
 
-func lookupLocalAddr(ifaceName string, network string, destination net.IP, port int) (net.Addr, error) {
+func lookupLocalAddr(ifaceName string, network string, destination netip.Addr, port int) (net.Addr, error) {
 	ifaceObj, err := iface.ResolveInterface(ifaceName)
 	if err != nil {
 		return nil, err
 	}
 
-	var addr *net.IPNet
+	var addr *netip.Prefix
 	switch network {
 	case "udp4", "tcp4":
 		addr, err = ifaceObj.PickIPv4Addr(destination)
 	case "tcp6", "udp6":
 		addr, err = ifaceObj.PickIPv6Addr(destination)
 	default:
-		if destination != nil {
+		if destination.IsValid() {
-			if destination.To4() != nil {
+			if destination.Is4() {
 				addr, err = ifaceObj.PickIPv4Addr(destination)
 			} else {
 				addr, err = ifaceObj.PickIPv6Addr(destination)
@@ -39,12 +40,12 @@ func lookupLocalAddr(ifaceName string, network string, destination net.IP, port
 
 	if strings.HasPrefix(network, "tcp") {
 		return &net.TCPAddr{
-			IP:   addr.IP,
+			IP:   addr.Addr().AsSlice(),
 			Port: port,
 		}, nil
 	} else if strings.HasPrefix(network, "udp") {
 		return &net.UDPAddr{
-			IP:   addr.IP,
+			IP:   addr.Addr().AsSlice(),
 			Port: port,
 		}, nil
 	}
@@ -52,7 +53,7 @@ func lookupLocalAddr(ifaceName string, network string, destination net.IP, port
 	return nil, iface.ErrAddrNotFound
 }
 
-func bindIfaceToDialer(ifaceName string, dialer *net.Dialer, network string, destination net.IP) error {
+func bindIfaceToDialer(ifaceName string, dialer *net.Dialer, network string, destination netip.Addr) error {
 	if !destination.IsGlobalUnicast() {
 		return nil
 	}
@@ -83,7 +84,7 @@ func bindIfaceToListenConfig(ifaceName string, _ *net.ListenConfig, network, add
 
 	local, _ := strconv.ParseUint(port, 10, 16)
 
-	addr, err := lookupLocalAddr(ifaceName, network, nil, int(local))
+	addr, err := lookupLocalAddr(ifaceName, network, netip.Addr{}, int(local))
 	if err != nil {
 		return "", err
 	}

component/dialer/dialer.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"net"
+	"net/netip"
 
 	"github.com/Dreamacro/clash/component/resolver"
 )
@@ -29,7 +30,7 @@ func DialContext(ctx context.Context, network, address string, options ...Option
 			return nil, err
 		}
 
-		var ip net.IP
+		var ip netip.Addr
 		switch network {
 		case "tcp4", "udp4":
 			if !opt.direct {
@@ -88,7 +89,7 @@ func ListenPacket(ctx context.Context, network, address string, options ...Optio
 	return lc.ListenPacket(ctx, network, address)
 }
 
-func dialContext(ctx context.Context, network string, destination net.IP, port string, opt *option) (net.Conn, error) {
+func dialContext(ctx context.Context, network string, destination netip.Addr, port string, opt *option) (net.Conn, error) {
 	dialer := &net.Dialer{}
 	if opt.interfaceName != "" {
 		if err := bindIfaceToDialer(opt.interfaceName, dialer, network, destination); err != nil {
@@ -128,12 +129,12 @@ func dualStackDialContext(ctx context.Context, network, address string, opt *opt
 			case results <- result:
 			case <-returned:
 				if result.Conn != nil {
-					result.Conn.Close()
+					_ = result.Conn.Close()
 				}
 			}
 		}()
 
-		var ip net.IP
+		var ip netip.Addr
 		if ipv6 {
 			if !direct {
 				ip, result.error = resolver.ResolveIPv6ProxyServerHost(host)

component/dialer/mark_linux.go

@@ -4,14 +4,15 @@ package dialer
 
 import (
 	"net"
+	"net/netip"
 	"syscall"
 )
 
-func bindMarkToDialer(mark int, dialer *net.Dialer, _ string, _ net.IP) {
+func bindMarkToDialer(mark int, dialer *net.Dialer, _ string, _ netip.Addr) {
 	dialer.Control = bindMarkToControl(mark, dialer.Control)
 }
 
-func bindMarkToListenConfig(mark int, lc *net.ListenConfig, _, address string) {
+func bindMarkToListenConfig(mark int, lc *net.ListenConfig, _, _ string) {
 	lc.Control = bindMarkToControl(mark, lc.Control)
 }
 
@@ -23,20 +24,17 @@ func bindMarkToControl(mark int, chain controlFn) controlFn {
 			}
 		}()
 
-		ipStr, _, err := net.SplitHostPort(address)
+		addrPort, err := netip.ParseAddrPort(address)
-		if err == nil {
+		if err == nil && !addrPort.Addr().IsGlobalUnicast() {
-			ip := net.ParseIP(ipStr)
-			if ip != nil && !ip.IsGlobalUnicast() {
 			return
 		}
-		}
 
 		return c.Control(func(fd uintptr) {
 			switch network {
 			case "tcp4", "udp4":
-				syscall.SetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_MARK, mark)
+				_ = syscall.SetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_MARK, mark)
 			case "tcp6", "udp6":
-				syscall.SetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_MARK, mark)
+				_ = syscall.SetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_MARK, mark)
 			}
 		})
 	}

component/dialer/mark_nonlinux.go

@@ -4,6 +4,7 @@ package dialer
 
 import (
 	"net"
+	"net/netip"
 	"sync"
 
 	"github.com/Dreamacro/clash/log"
@@ -17,10 +18,10 @@ func printMarkWarn() {
 	})
 }
 
-func bindMarkToDialer(mark int, dialer *net.Dialer, _ string, _ net.IP) {
+func bindMarkToDialer(mark int, dialer *net.Dialer, _ string, _ netip.Addr) {
 	printMarkWarn()
 }
 
-func bindMarkToListenConfig(mark int, lc *net.ListenConfig, _, address string) {
+func bindMarkToListenConfig(mark int, lc *net.ListenConfig, _, _ string) {
 	printMarkWarn()
 }

component/dialer/resolver.go

@@ -3,6 +3,7 @@ package dialer
 import (
 	"context"
 	"net"
+	"net/netip"
 )
 
 func init() {
@@ -18,9 +19,9 @@ func resolverDialContext(ctx context.Context, network, address string) (net.Conn
 	interfaceName := DefaultInterface.Load()
 
 	if interfaceName != "" {
-		dstIP := net.ParseIP(address)
+		dstIP, err := netip.ParseAddr(address)
-		if dstIP != nil {
+		if err == nil {
-			bindIfaceToDialer(interfaceName, d, network, dstIP)
+			_ = bindIfaceToDialer(interfaceName, d, network, dstIP)
 		}
 	}
 

component/iface/iface.go

@@ -3,6 +3,7 @@ package iface
 import (
 	"errors"
 	"net"
+	"net/netip"
 	"time"
 
 	"github.com/Dreamacro/clash/common/singledo"
@@ -11,7 +12,7 @@ import (
 type Interface struct {
 	Index        int
 	Name         string
-	Addrs        []*net.IPNet
+	Addrs        []*netip.Prefix
 	HardwareAddr net.HardwareAddr
 }
 
@@ -37,14 +38,18 @@ func ResolveInterface(name string) (*Interface, error) {
 				continue
 			}
 
-			ipNets := make([]*net.IPNet, 0, len(addrs))
+			ipNets := make([]*netip.Prefix, 0, len(addrs))
 			for _, addr := range addrs {
 				ipNet := addr.(*net.IPNet)
-				if v4 := ipNet.IP.To4(); v4 != nil {
+				ip, _ := netip.AddrFromSlice(ipNet.IP)
-					ipNet.IP = v4
+
+				ones, bits := ipNet.Mask.Size()
+				if bits == 32 {
+					ip = ip.Unmap()
 				}
 
-				ipNets = append(ipNets, ipNet)
+				pf := netip.PrefixFrom(ip, ones)
+				ipNets = append(ipNets, &pf)
 			}
 
 			r[iface.Name] = &Interface{
@@ -74,35 +79,35 @@ func FlushCache() {
 	interfaces.Reset()
 }
 
-func (iface *Interface) PickIPv4Addr(destination net.IP) (*net.IPNet, error) {
+func (iface *Interface) PickIPv4Addr(destination netip.Addr) (*netip.Prefix, error) {
-	return iface.pickIPAddr(destination, func(addr *net.IPNet) bool {
+	return iface.pickIPAddr(destination, func(addr *netip.Prefix) bool {
-		return addr.IP.To4() != nil
+		return addr.Addr().Is4()
 	})
 }
 
-func (iface *Interface) PickIPv6Addr(destination net.IP) (*net.IPNet, error) {
+func (iface *Interface) PickIPv6Addr(destination netip.Addr) (*netip.Prefix, error) {
-	return iface.pickIPAddr(destination, func(addr *net.IPNet) bool {
+	return iface.pickIPAddr(destination, func(addr *netip.Prefix) bool {
-		return addr.IP.To4() == nil
+		return addr.Addr().Is6()
 	})
 }
 
-func (iface *Interface) pickIPAddr(destination net.IP, accept func(addr *net.IPNet) bool) (*net.IPNet, error) {
+func (iface *Interface) pickIPAddr(destination netip.Addr, accept func(addr *netip.Prefix) bool) (*netip.Prefix, error) {
-	var fallback *net.IPNet
+	var fallback *netip.Prefix
 
 	for _, addr := range iface.Addrs {
 		if !accept(addr) {
 			continue
 		}
 
-		if fallback == nil && !addr.IP.IsLinkLocalUnicast() {
+		if fallback == nil && !addr.Addr().IsLinkLocalUnicast() {
 			fallback = addr
 
-			if destination == nil {
+			if !destination.IsValid() {
 				break
 			}
 		}
 
-		if destination != nil && addr.Contains(destination) {
+		if destination.IsValid() && addr.Contains(destination) {
 			return addr, nil
 		}
 	}

component/process/process.go

@@ -3,8 +3,10 @@ package process
 import (
 	"errors"
 	"net"
+	"net/netip"
 	"runtime"
 
+	"github.com/Dreamacro/clash/common/nnip"
 	C "github.com/Dreamacro/clash/constant"
 )
 
@@ -19,7 +21,7 @@ const (
 	UDP = "udp"
 )
 
-func FindProcessName(network string, srcIP net.IP, srcPort int) (string, error) {
+func FindProcessName(network string, srcIP netip.Addr, srcPort int) (string, error) {
 	return findProcessName(network, srcIP, srcPort)
 }
 
@@ -31,23 +33,23 @@ func ShouldFindProcess(metadata *C.Metadata) bool {
 		return false
 	}
 	for _, ip := range localIPs {
-		if ip.Equal(metadata.SrcIP) {
+		if ip == metadata.SrcIP {
 			return true
 		}
 	}
 	return false
 }
 
-func AppendLocalIPs(ip ...net.IP) {
+func AppendLocalIPs(ip ...netip.Addr) {
 	localIPs = append(ip, localIPs...)
 }
 
-func getLocalIPs() []net.IP {
+func getLocalIPs() []netip.Addr {
-	ips := []net.IP{net.IPv4zero, net.IPv6zero}
+	ips := []netip.Addr{netip.IPv4Unspecified(), netip.IPv6Unspecified()}
 
 	netInterfaces, err := net.Interfaces()
 	if err != nil {
-		ips = append(ips, net.IPv4(127, 0, 0, 1), net.IPv6loopback)
+		ips = append(ips, netip.AddrFrom4([4]byte{127, 0, 0, 1}), nnip.IpToAddr(net.IPv6loopback))
 		return ips
 	}
 
@@ -57,7 +59,7 @@ func getLocalIPs() []net.IP {
 
 			for _, address := range adds {
 				if ipNet, ok := address.(*net.IPNet); ok {
-					ips = append(ips, ipNet.IP)
+					ips = append(ips, nnip.IpToAddr(ipNet.IP))
 				}
 			}
 		}
@@ -66,7 +68,7 @@ func getLocalIPs() []net.IP {
 	return ips
 }
 
-var localIPs []net.IP
+var localIPs []netip.Addr
 
 func init() {
 	localIPs = getLocalIPs()

component/process/process_darwin.go

@@ -2,10 +2,12 @@ package process
 
 import (
 	"encoding/binary"
-	"net"
+	"net/netip"
 	"syscall"
 	"unsafe"
 
+	"github.com/Dreamacro/clash/common/nnip"
+
 	"golang.org/x/sys/unix"
 )
 
@@ -15,7 +17,7 @@ const (
 	proccallnumpidinfo  = 0x2
 )
 
-func findProcessName(network string, ip net.IP, port int) (string, error) {
+func findProcessName(network string, ip netip.Addr, port int) (string, error) {
 	var spath string
 	switch network {
 	case TCP:
@@ -26,7 +28,7 @@ func findProcessName(network string, ip net.IP, port int) (string, error) {
 		return "", ErrInvalidNetwork
 	}
 
-	isIPv4 := ip.To4() != nil
+	isIPv4 := ip.Is4()
 
 	value, err := syscall.Sysctl(spath)
 	if err != nil {
@@ -57,19 +59,19 @@ func findProcessName(network string, ip net.IP, port int) (string, error) {
 		// xinpcb_n.inp_vflag
 		flag := buf[inp+44]
 
-		var srcIP net.IP
+		var srcIP netip.Addr
 		switch {
 		case flag&0x1 > 0 && isIPv4:
 			// ipv4
-			srcIP = net.IP(buf[inp+76 : inp+80])
+			srcIP = nnip.IpToAddr(buf[inp+76 : inp+80])
 		case flag&0x2 > 0 && !isIPv4:
 			// ipv6
-			srcIP = net.IP(buf[inp+64 : inp+80])
+			srcIP = nnip.IpToAddr(buf[inp+64 : inp+80])
 		default:
 			continue
 		}
 
-		if !ip.Equal(srcIP) && (network == TCP || !srcIP.IsUnspecified()) {
+		if ip != srcIP && (network == TCP || !srcIP.IsUnspecified()) {
 			continue
 		}
 

component/process/process_freebsd_amd64.go

@@ -3,13 +3,14 @@ package process
 import (
 	"encoding/binary"
 	"fmt"
-	"net"
+	"net/netip"
 	"strconv"
 	"strings"
 	"sync"
 	"syscall"
 	"unsafe"
 
+	"github.com/Dreamacro/clash/common/nnip"
 	"github.com/Dreamacro/clash/log"
 )
 
@@ -20,7 +21,7 @@ var (
 	once sync.Once
 )
 
-func findProcessName(network string, ip net.IP, srcPort int) (string, error) {
+func findProcessName(network string, ip netip.Addr, srcPort int) (string, error) {
 	once.Do(func() {
 		if err := initSearcher(); err != nil {
 			log.Errorln("Initialize PROCESS-NAME failed: %s", err.Error())
@@ -102,7 +103,7 @@ type searcher struct {
 	pid          int
 }
 
-func (s *searcher) Search(buf []byte, ip net.IP, port uint16, isTCP bool) (uint32, error) {
+func (s *searcher) Search(buf []byte, ip netip.Addr, port uint16, isTCP bool) (uint32, error) {
 	var itemSize int
 	var inpOffset int
 
@@ -116,7 +117,7 @@ func (s *searcher) Search(buf []byte, ip net.IP, port uint16, isTCP bool) (uint3
 		inpOffset = s.udpInpOffset
 	}
 
-	isIPv4 := ip.To4() != nil
+	isIPv4 := ip.Is4()
 	// skip the first xinpgen block
 	for i := s.headSize; i+itemSize <= len(buf); i += itemSize {
 		inp := i + inpOffset
@@ -130,19 +131,19 @@ func (s *searcher) Search(buf []byte, ip net.IP, port uint16, isTCP bool) (uint3
 		// xinpcb.inp_vflag
 		flag := buf[inp+s.vflag]
 
-		var srcIP net.IP
+		var srcIP netip.Addr
 		switch {
 		case flag&0x1 > 0 && isIPv4:
 			// ipv4
-			srcIP = net.IP(buf[inp+s.ip : inp+s.ip+4])
+			srcIP = nnip.IpToAddr(buf[inp+s.ip : inp+s.ip+4])
 		case flag&0x2 > 0 && !isIPv4:
 			// ipv6
-			srcIP = net.IP(buf[inp+s.ip-12 : inp+s.ip+4])
+			srcIP = nnip.IpToAddr(buf[inp+s.ip-12 : inp+s.ip+4])
 		default:
 			continue
 		}
 
-		if !ip.Equal(srcIP) {
+		if ip != srcIP {
 			continue
 		}
 

component/process/process_linux.go

@@ -5,6 +5,7 @@ import (
 	"encoding/binary"
 	"fmt"
 	"net"
+	"net/netip"
 	"os"
 	"path"
 	"strings"
@@ -31,7 +32,7 @@ const (
 	pathProc                = "/proc"
 )
 
-func findProcessName(network string, ip net.IP, srcPort int) (string, error) {
+func findProcessName(network string, ip netip.Addr, srcPort int) (string, error) {
 	inode, uid, err := resolveSocketByNetlink(network, ip, srcPort)
 	if err != nil {
 		return "", err
@@ -40,7 +41,7 @@ func findProcessName(network string, ip net.IP, srcPort int) (string, error) {
 	return resolveProcessNameByProcSearch(inode, uid)
 }
 
-func resolveSocketByNetlink(network string, ip net.IP, srcPort int) (int32, int32, error) {
+func resolveSocketByNetlink(network string, ip netip.Addr, srcPort int) (int32, int32, error) {
 	var family byte
 	var protocol byte
 
@@ -53,7 +54,7 @@ func resolveSocketByNetlink(network string, ip net.IP, srcPort int) (int32, int3
 		return 0, 0, ErrInvalidNetwork
 	}
 
-	if ip.To4() != nil {
+	if ip.Is4() {
 		family = syscall.AF_INET
 	} else {
 		family = syscall.AF_INET6
@@ -65,10 +66,12 @@ func resolveSocketByNetlink(network string, ip net.IP, srcPort int) (int32, int3
 	if err != nil {
 		return 0, 0, fmt.Errorf("dial netlink: %w", err)
 	}
-	defer syscall.Close(socket)
+	defer func() {
+		_ = syscall.Close(socket)
+	}()
 
-	syscall.SetsockoptTimeval(socket, syscall.SOL_SOCKET, syscall.SO_SNDTIMEO, &syscall.Timeval{Usec: 100})
+	_ = syscall.SetsockoptTimeval(socket, syscall.SOL_SOCKET, syscall.SO_SNDTIMEO, &syscall.Timeval{Usec: 100})
-	syscall.SetsockoptTimeval(socket, syscall.SOL_SOCKET, syscall.SO_RCVTIMEO, &syscall.Timeval{Usec: 100})
+	_ = syscall.SetsockoptTimeval(socket, syscall.SOL_SOCKET, syscall.SO_RCVTIMEO, &syscall.Timeval{Usec: 100})
 
 	if err := syscall.Connect(socket, &syscall.SockaddrNetlink{
 		Family: syscall.AF_NETLINK,
@@ -84,7 +87,9 @@ func resolveSocketByNetlink(network string, ip net.IP, srcPort int) (int32, int3
 	}
 
 	rb := pool.Get(pool.RelayBufferSize)
-	defer pool.Put(rb)
+	defer func() {
+		_ = pool.Put(rb)
+	}()
 
 	n, err := syscall.Read(socket, rb)
 	if err != nil {
@@ -111,14 +116,10 @@ func resolveSocketByNetlink(network string, ip net.IP, srcPort int) (int32, int3
 	return inode, uid, nil
 }
 
-func packSocketDiagRequest(family, protocol byte, source net.IP, sourcePort uint16) []byte {
+func packSocketDiagRequest(family, protocol byte, source netip.Addr, sourcePort uint16) []byte {
 	s := make([]byte, 16)
 
-	if v4 := source.To4(); v4 != nil {
+	copy(s, source.AsSlice())
-		copy(s, v4)
-	} else {
-		copy(s, source)
-	}
 
 	buf := make([]byte, sizeOfSocketDiagRequest)
 

component/process/process_other.go

@@ -2,8 +2,8 @@
 
 package process
 
-import "net"
+import "net/netip"
 
-func findProcessName(network string, ip net.IP, srcPort int) (string, error) {
+func findProcessName(network string, ip netip.Addr, srcPort int) (string, error) {
 	return "", ErrPlatformNotSupport
 }

component/process/process_windows.go

@@ -2,11 +2,12 @@ package process
 
 import (
 	"fmt"
-	"net"
+	"net/netip"
 	"sync"
 	"syscall"
 	"unsafe"
 
+	"github.com/Dreamacro/clash/common/nnip"
 	"github.com/Dreamacro/clash/log"
 
 	"golang.org/x/sys/windows"
@@ -57,7 +58,7 @@ func initWin32API() error {
 	return nil
 }
 
-func findProcessName(network string, ip net.IP, srcPort int) (string, error) {
+func findProcessName(network string, ip netip.Addr, srcPort int) (string, error) {
 	once.Do(func() {
 		err := initWin32API()
 		if err != nil {
@@ -67,7 +68,7 @@ func findProcessName(network string, ip net.IP, srcPort int) (string, error) {
 		}
 	})
 	family := windows.AF_INET
-	if ip.To4() == nil {
+	if ip.Is6() {
 		family = windows.AF_INET6
 	}
 
@@ -107,7 +108,7 @@ type searcher struct {
 	tcpState int
 }
 
-func (s *searcher) Search(b []byte, ip net.IP, port uint16) (uint32, error) {
+func (s *searcher) Search(b []byte, ip netip.Addr, port uint16) (uint32, error) {
 	n := int(readNativeUint32(b[:4]))
 	itemSize := s.itemSize
 	for i := 0; i < n; i++ {
@@ -131,9 +132,9 @@ func (s *searcher) Search(b []byte, ip net.IP, port uint16) (uint32, error) {
 			continue
 		}
 
-		srcIP := net.IP(row[s.ip : s.ip+s.ipSize])
+		srcIP := nnip.IpToAddr(row[s.ip : s.ip+s.ipSize])
 		// windows binds an unbound udp socket to 0.0.0.0/[::] while first sendto
-		if !ip.Equal(srcIP) && (!srcIP.IsUnspecified() || s.tcpState != -1) {
+		if ip != srcIP && (!srcIP.IsUnspecified() || s.tcpState != -1) {
 			continue
 		}
 

component/resolver/enhancer.go

@@ -1,20 +1,18 @@
 package resolver
 
-import (
+import "net/netip"
-	"net"
-)
 
 var DefaultHostMapper Enhancer
 
 type Enhancer interface {
 	FakeIPEnabled() bool
 	MappingEnabled() bool
-	IsFakeIP(net.IP) bool
+	IsFakeIP(netip.Addr) bool
-	IsFakeBroadcastIP(net.IP) bool
+	IsFakeBroadcastIP(netip.Addr) bool
-	IsExistFakeIP(net.IP) bool
+	IsExistFakeIP(netip.Addr) bool
-	FindHostByIP(net.IP) (string, bool)
+	FindHostByIP(netip.Addr) (string, bool)
 	FlushFakeIP() error
-	InsertHostByIP(net.IP, string)
+	InsertHostByIP(netip.Addr, string)
 	StoreFakePoolState()
 }
 
@@ -34,7 +32,7 @@ func MappingEnabled() bool {
 	return false
 }
 
-func IsFakeIP(ip net.IP) bool {
+func IsFakeIP(ip netip.Addr) bool {
 	if mapper := DefaultHostMapper; mapper != nil {
 		return mapper.IsFakeIP(ip)
 	}
@@ -42,7 +40,7 @@ func IsFakeIP(ip net.IP) bool {
 	return false
 }
 
-func IsFakeBroadcastIP(ip net.IP) bool {
+func IsFakeBroadcastIP(ip netip.Addr) bool {
 	if mapper := DefaultHostMapper; mapper != nil {
 		return mapper.IsFakeBroadcastIP(ip)
 	}
@@ -50,7 +48,7 @@ func IsFakeBroadcastIP(ip net.IP) bool {
 	return false
 }
 
-func IsExistFakeIP(ip net.IP) bool {
+func IsExistFakeIP(ip netip.Addr) bool {
 	if mapper := DefaultHostMapper; mapper != nil {
 		return mapper.IsExistFakeIP(ip)
 	}
@@ -58,13 +56,13 @@ func IsExistFakeIP(ip net.IP) bool {
 	return false
 }
 
-func InsertHostByIP(ip net.IP, host string) {
+func InsertHostByIP(ip netip.Addr, host string) {
 	if mapper := DefaultHostMapper; mapper != nil {
 		mapper.InsertHostByIP(ip, host)
 	}
 }
 
-func FindHostByIP(ip net.IP) (string, bool) {
+func FindHostByIP(ip netip.Addr) (string, bool) {
 	if mapper := DefaultHostMapper; mapper != nil {
 		return mapper.FindHostByIP(ip)
 	}

component/resolver/resolver.go

@@ -6,9 +6,9 @@ import (
 	"math/rand"
 	"net"
 	"net/netip"
-	"strings"
 	"time"
 
+	"github.com/Dreamacro/clash/common/nnip"
 	"github.com/Dreamacro/clash/component/trie"
 )
 
@@ -37,29 +37,29 @@ var (
 )
 
 type Resolver interface {
-	ResolveIP(host string) (ip net.IP, err error)
+	ResolveIP(host string) (ip netip.Addr, err error)
-	ResolveIPv4(host string) (ip net.IP, err error)
+	ResolveIPv4(host string) (ip netip.Addr, err error)
-	ResolveIPv6(host string) (ip net.IP, err error)
+	ResolveIPv6(host string) (ip netip.Addr, err error)
 }
 
 // ResolveIPv4 with a host, return ipv4
-func ResolveIPv4(host string) (net.IP, error) {
+func ResolveIPv4(host string) (netip.Addr, error) {
 	return ResolveIPv4WithResolver(host, DefaultResolver)
 }
 
-func ResolveIPv4WithResolver(host string, r Resolver) (net.IP, error) {
+func ResolveIPv4WithResolver(host string, r Resolver) (netip.Addr, error) {
 	if node := DefaultHosts.Search(host); node != nil {
 		if ip := node.Data; ip.Is4() {
-			return ip.AsSlice(), nil
+			return ip, nil
 		}
 	}
 
-	ip := net.ParseIP(host)
+	ip, err := netip.ParseAddr(host)
-	if ip != nil {
+	if err == nil {
-		if !strings.Contains(host, ":") {
+		if ip.Is4() {
 			return ip, nil
 		}
-		return nil, ErrIPVersion
+		return netip.Addr{}, ErrIPVersion
 	}
 
 	if r != nil {
@@ -71,39 +71,44 @@ func ResolveIPv4WithResolver(host string, r Resolver) (net.IP, error) {
 		defer cancel()
 		ipAddrs, err := net.DefaultResolver.LookupIP(ctx, "ip4", host)
 		if err != nil {
-			return nil, err
+			return netip.Addr{}, err
 		} else if len(ipAddrs) == 0 {
-			return nil, ErrIPNotFound
+			return netip.Addr{}, ErrIPNotFound
 		}
 
-		return ipAddrs[rand.Intn(len(ipAddrs))], nil
+		ip := ipAddrs[rand.Intn(len(ipAddrs))].To4()
+		if ip == nil {
+			return netip.Addr{}, ErrIPVersion
 		}
 
-	return nil, ErrIPNotFound
+		return netip.AddrFrom4(*(*[4]byte)(ip)), nil
+	}
+
+	return netip.Addr{}, ErrIPNotFound
 }
 
 // ResolveIPv6 with a host, return ipv6
-func ResolveIPv6(host string) (net.IP, error) {
+func ResolveIPv6(host string) (netip.Addr, error) {
 	return ResolveIPv6WithResolver(host, DefaultResolver)
 }
 
-func ResolveIPv6WithResolver(host string, r Resolver) (net.IP, error) {
+func ResolveIPv6WithResolver(host string, r Resolver) (netip.Addr, error) {
 	if DisableIPv6 {
-		return nil, ErrIPv6Disabled
+		return netip.Addr{}, ErrIPv6Disabled
 	}
 
 	if node := DefaultHosts.Search(host); node != nil {
 		if ip := node.Data; ip.Is6() {
-			return ip.AsSlice(), nil
+			return ip, nil
 		}
 	}
 
-	ip := net.ParseIP(host)
+	ip, err := netip.ParseAddr(host)
-	if ip != nil {
+	if err == nil {
-		if strings.Contains(host, ":") {
+		if ip.Is6() {
 			return ip, nil
 		}
-		return nil, ErrIPVersion
+		return netip.Addr{}, ErrIPVersion
 	}
 
 	if r != nil {
@@ -115,22 +120,21 @@ func ResolveIPv6WithResolver(host string, r Resolver) (net.IP, error) {
 		defer cancel()
 		ipAddrs, err := net.DefaultResolver.LookupIP(ctx, "ip6", host)
 		if err != nil {
-			return nil, err
+			return netip.Addr{}, err
 		} else if len(ipAddrs) == 0 {
-			return nil, ErrIPNotFound
+			return netip.Addr{}, ErrIPNotFound
 		}
 
-		return ipAddrs[rand.Intn(len(ipAddrs))], nil
+		return netip.AddrFrom16(*(*[16]byte)(ipAddrs[rand.Intn(len(ipAddrs))])), nil
 	}
 
-	return nil, ErrIPNotFound
+	return netip.Addr{}, ErrIPNotFound
 }
 
 // ResolveIPWithResolver same as ResolveIP, but with a resolver
-func ResolveIPWithResolver(host string, r Resolver) (net.IP, error) {
+func ResolveIPWithResolver(host string, r Resolver) (netip.Addr, error) {
 	if node := DefaultHosts.Search(host); node != nil {
-		ip := node.Data
+		return node.Data, nil
-		return ip.Unmap().AsSlice(), nil
 	}
 
 	if r != nil {
@@ -142,30 +146,30 @@ func ResolveIPWithResolver(host string, r Resolver) (net.IP, error) {
 		return ResolveIPv4(host)
 	}
 
-	ip := net.ParseIP(host)
+	ip, err := netip.ParseAddr(host)
-	if ip != nil {
+	if err == nil {
 		return ip, nil
 	}
 
 	if DefaultResolver == nil {
 		ipAddr, err := net.ResolveIPAddr("ip", host)
 		if err != nil {
-			return nil, err
+			return netip.Addr{}, err
 		}
 
-		return ipAddr.IP, nil
+		return nnip.IpToAddr(ipAddr.IP), nil
 	}
 
-	return nil, ErrIPNotFound
+	return netip.Addr{}, ErrIPNotFound
 }
 
 // ResolveIP with a host, return ip
-func ResolveIP(host string) (net.IP, error) {
+func ResolveIP(host string) (netip.Addr, error) {
 	return ResolveIPWithResolver(host, DefaultResolver)
 }
 
 // ResolveIPv4ProxyServerHost proxies server host only
-func ResolveIPv4ProxyServerHost(host string) (net.IP, error) {
+func ResolveIPv4ProxyServerHost(host string) (netip.Addr, error) {
 	if ProxyServerHostResolver != nil {
 		return ResolveIPv4WithResolver(host, ProxyServerHostResolver)
 	}
@@ -173,7 +177,7 @@ func ResolveIPv4ProxyServerHost(host string) (net.IP, error) {
 }
 
 // ResolveIPv6ProxyServerHost proxies server host only
-func ResolveIPv6ProxyServerHost(host string) (net.IP, error) {
+func ResolveIPv6ProxyServerHost(host string) (netip.Addr, error) {
 	if ProxyServerHostResolver != nil {
 		return ResolveIPv6WithResolver(host, ProxyServerHostResolver)
 	}
@@ -181,7 +185,7 @@ func ResolveIPv6ProxyServerHost(host string) (net.IP, error) {
 }
 
 // ResolveProxyServerHost proxies server host only
-func ResolveProxyServerHost(host string) (net.IP, error) {
+func ResolveProxyServerHost(host string) (netip.Addr, error) {
 	if ProxyServerHostResolver != nil {
 		return ResolveIPWithResolver(host, ProxyServerHostResolver)
 	}

component/sniffer/dispatcher.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"github.com/Dreamacro/clash/component/trie"
 	"net"
+	"net/netip"
 
 	CN "github.com/Dreamacro/clash/common/net"
 	"github.com/Dreamacro/clash/component/resolver"
@@ -58,7 +59,7 @@ func (sd *SnifferDispatcher) replaceDomain(metadata *C.Metadata, host string) {
 	metadata.Host = host
 	metadata.DNSMode = C.DNSMapping
 	resolver.InsertHostByIP(metadata.DstIP, host)
-	metadata.DstIP = nil
+	metadata.DstIP = netip.Addr{}
 }
 
 func (sd *SnifferDispatcher) Enable() bool {

config/config.go

@@ -87,7 +87,7 @@ type DNS struct {
 type FallbackFilter struct {
 	GeoIP     bool                    `yaml:"geoip"`
 	GeoIPCode string                  `yaml:"geoip-code"`
-	IPCIDR    []*net.IPNet            `yaml:"ipcidr"`
+	IPCIDR    []*netip.Prefix         `yaml:"ipcidr"`
 	Domain    []string                `yaml:"domain"`
 	GeoSite   []*router.DomainMatcher `yaml:"geosite"`
 }
@@ -702,15 +702,15 @@ func parseNameServerPolicy(nsPolicy map[string]string) (map[string]dns.NameServe
 	return policy, nil
 }
 
-func parseFallbackIPCIDR(ips []string) ([]*net.IPNet, error) {
+func parseFallbackIPCIDR(ips []string) ([]*netip.Prefix, error) {
-	var ipNets []*net.IPNet
+	var ipNets []*netip.Prefix
 
 	for idx, ip := range ips {
-		_, ipnet, err := net.ParseCIDR(ip)
+		ipnet, err := netip.ParsePrefix(ip)
 		if err != nil {
 			return nil, fmt.Errorf("DNS FallbackIP[%d] format error: %s", idx, err.Error())
 		}
-		ipNets = append(ipNets, ipnet)
+		ipNets = append(ipNets, &ipnet)
 	}
 
 	return ipNets, nil
@@ -763,7 +763,7 @@ func parseDNS(rawCfg *RawConfig, hosts *trie.DomainTrie[netip.Addr], rules []C.R
 		IPv6:         cfg.IPv6,
 		EnhancedMode: cfg.EnhancedMode,
 		FallbackFilter: FallbackFilter{
-			IPCIDR:  []*net.IPNet{},
+			IPCIDR:  []*netip.Prefix{},
 			GeoSite: []*router.DomainMatcher{},
 		},
 	}

constant/metadata.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net"
+	"net/netip"
 	"strconv"
 )
 
@@ -75,8 +76,8 @@ func (t Type) MarshalJSON() ([]byte, error) {
 type Metadata struct {
 	NetWork     NetWork    `json:"network"`
 	Type        Type       `json:"type"`
-	SrcIP       net.IP  `json:"sourceIP"`
+	SrcIP       netip.Addr `json:"sourceIP"`
-	DstIP       net.IP  `json:"destinationIP"`
+	DstIP       netip.Addr `json:"destinationIP"`
 	SrcPort     string     `json:"sourcePort"`
 	DstPort     string     `json:"destinationPort"`
 	AddrType    int        `json:"-"`
@@ -84,11 +85,15 @@ type Metadata struct {
 	DNSMode     DNSMode    `json:"dnsMode"`
 	Process     string     `json:"process"`
 	ProcessPath string     `json:"processPath"`
+	UserAgent   string     `json:"userAgent"`
 }
 
 func (m *Metadata) RemoteAddress() string {
+	if m.DstIP.IsValid() {
+		return net.JoinHostPort(m.DstIP.String(), m.DstPort)
+	} else {
 		return net.JoinHostPort(m.String(), m.DstPort)
-	
+	}
 }
 
 func (m *Metadata) SourceAddress() string {
@@ -108,33 +113,33 @@ func (m *Metadata) SourceDetail() string {
 }
 
 func (m *Metadata) Resolved() bool {
-	return m.DstIP != nil
+	return m.DstIP.IsValid()
 }
 
 // Pure is used to solve unexpected behavior
 // when dialing proxy connection in DNSMapping mode.
 func (m *Metadata) Pure() *Metadata {
-	if m.DNSMode == DNSMapping && m.DstIP != nil {
+	if m.DNSMode == DNSMapping && m.DstIP.IsValid() {
-		copy := *m
+		copyM := *m
-		copy.Host = ""
+		copyM.Host = ""
-		if copy.DstIP.To4() != nil {
+		if copyM.DstIP.Is4() {
-			copy.AddrType = AtypIPv4
+			copyM.AddrType = AtypIPv4
 		} else {
-			copy.AddrType = AtypIPv6
+			copyM.AddrType = AtypIPv6
 		}
-		return &copy
+		return &copyM
 	}
 
 	return m
 }
 
 func (m *Metadata) UDPAddr() *net.UDPAddr {
-	if m.NetWork != UDP || m.DstIP == nil {
+	if m.NetWork != UDP || !m.DstIP.IsValid() {
 		return nil
 	}
 	port, _ := strconv.ParseUint(m.DstPort, 10, 16)
 	return &net.UDPAddr{
-		IP:   m.DstIP,
+		IP:   m.DstIP.AsSlice(),
 		Port: int(port),
 	}
 }
@@ -142,7 +147,7 @@ func (m *Metadata) UDPAddr() *net.UDPAddr {
 func (m *Metadata) String() string {
 	if m.Host != "" {
 		return m.Host
-	} else if m.DstIP != nil {
+	} else if m.DstIP.IsValid() {
 		return m.DstIP.String()
 	} else {
 		return "<nil>"
@@ -150,5 +155,5 @@ func (m *Metadata) String() string {
 }
 
 func (m *Metadata) Valid() bool {
-	return m.Host != "" || m.DstIP != nil
+	return m.Host != "" || m.DstIP.IsValid()
 }

constant/rule_extra.go

@@ -1,7 +1,7 @@
 package constant
 
 import (
-	"net"
+	"net/netip"
 	"strings"
 
 	"github.com/Dreamacro/clash/component/geodata/router"
@@ -9,7 +9,7 @@ import (
 
 type RuleExtra struct {
 	Network      NetWork
-	SourceIPs    []*net.IPNet
+	SourceIPs    []*netip.Prefix
 	ProcessNames []string
 }
 
@@ -17,7 +17,7 @@ func (re *RuleExtra) NotMatchNetwork(network NetWork) bool {
 	return re.Network != ALLNet && re.Network != network
 }
 
-func (re *RuleExtra) NotMatchSourceIP(srcIP net.IP) bool {
+func (re *RuleExtra) NotMatchSourceIP(srcIP netip.Addr) bool {
 	if re.SourceIPs == nil {
 		return false
 	}

dns/client.go

@@ -5,6 +5,7 @@ import (
 	"crypto/tls"
 	"fmt"
 	"net"
+	"net/netip"
 	"strings"
 
 	"github.com/Dreamacro/clash/component/dialer"
@@ -28,10 +29,10 @@ func (c *client) Exchange(m *D.Msg) (*D.Msg, error) {
 
 func (c *client) ExchangeContext(ctx context.Context, m *D.Msg) (*D.Msg, error) {
 	var (
-		ip  net.IP
+		ip  netip.Addr
 		err error
 	)
-	if ip = net.ParseIP(c.host); ip == nil {
+	if ip, err = netip.ParseAddr(c.host); err != nil {
 		if c.r == nil {
 			return nil, fmt.Errorf("dns %s not a valid ip", c.host)
 		} else {
@@ -62,7 +63,9 @@ func (c *client) ExchangeContext(ctx context.Context, m *D.Msg) (*D.Msg, error)
 	if err != nil {
 		return nil, err
 	}
-	defer conn.Close()
+	defer func() {
+		_ = conn.Close()
+	}()
 
 	// miekg/dns ExchangeContext doesn't respond to context cancel.
 	// this is a workaround

dns/dhcp.go

@@ -1,9 +1,9 @@
 package dns
 
 import (
-	"bytes"
 	"context"
 	"net"
+	"net/netip"
 	"sync"
 	"time"
 
@@ -27,7 +27,7 @@ type dhcpClient struct {
 	ifaceInvalidate time.Time
 	dnsInvalidate   time.Time
 
-	ifaceAddr *net.IPNet
+	ifaceAddr *netip.Prefix
 	done      chan struct{}
 	resolver  *Resolver
 	err       error
@@ -127,12 +127,12 @@ func (d *dhcpClient) invalidate() (bool, error) {
 		return false, err
 	}
 
-	addr, err := ifaceObj.PickIPv4Addr(nil)
+	addr, err := ifaceObj.PickIPv4Addr(netip.Addr{})
 	if err != nil {
 		return false, err
 	}
 
-	if time.Now().Before(d.dnsInvalidate) && d.ifaceAddr.IP.Equal(addr.IP) && bytes.Equal(d.ifaceAddr.Mask, addr.Mask) {
+	if time.Now().Before(d.dnsInvalidate) && d.ifaceAddr == addr {
 		return false, nil
 	}
 

dns/enhancer.go

@@ -1,11 +1,9 @@
 package dns
 
 import (
-	"net"
 	"net/netip"
 
 	"github.com/Dreamacro/clash/common/cache"
-	"github.com/Dreamacro/clash/common/nnip"
 	"github.com/Dreamacro/clash/component/fakeip"
 	C "github.com/Dreamacro/clash/constant"
 )
@@ -24,54 +22,51 @@ func (h *ResolverEnhancer) MappingEnabled() bool {
 	return h.mode == C.DNSFakeIP || h.mode == C.DNSMapping
 }
 
-func (h *ResolverEnhancer) IsExistFakeIP(ip net.IP) bool {
+func (h *ResolverEnhancer) IsExistFakeIP(ip netip.Addr) bool {
 	if !h.FakeIPEnabled() {
 		return false
 	}
 
 	if pool := h.fakePool; pool != nil {
-		return pool.Exist(nnip.IpToAddr(ip))
+		return pool.Exist(ip)
 	}
 
 	return false
 }
 
-func (h *ResolverEnhancer) IsFakeIP(ip net.IP) bool {
+func (h *ResolverEnhancer) IsFakeIP(ip netip.Addr) bool {
-	if !h.FakeIPEnabled() {
-		return false
-	}
-
-	addr := nnip.IpToAddr(ip)
-
-	if pool := h.fakePool; pool != nil {
-		return pool.IPNet().Contains(addr) && addr != pool.Gateway() && addr != pool.Broadcast()
-	}
-
-	return false
-}
-
-func (h *ResolverEnhancer) IsFakeBroadcastIP(ip net.IP) bool {
 	if !h.FakeIPEnabled() {
 		return false
 	}
 
 	if pool := h.fakePool; pool != nil {
-		return pool.Broadcast() == nnip.IpToAddr(ip)
+		return pool.IPNet().Contains(ip) && ip != pool.Gateway() && ip != pool.Broadcast()
 	}
 
 	return false
 }
 
-func (h *ResolverEnhancer) FindHostByIP(ip net.IP) (string, bool) {
+func (h *ResolverEnhancer) IsFakeBroadcastIP(ip netip.Addr) bool {
-	addr := nnip.IpToAddr(ip)
+	if !h.FakeIPEnabled() {
+		return false
+	}
+
 	if pool := h.fakePool; pool != nil {
-		if host, existed := pool.LookBack(addr); existed {
+		return pool.Broadcast() == ip
+	}
+
+	return false
+}
+
+func (h *ResolverEnhancer) FindHostByIP(ip netip.Addr) (string, bool) {
+	if pool := h.fakePool; pool != nil {
+		if host, existed := pool.LookBack(ip); existed {
 			return host, true
 		}
 	}
 
 	if mapping := h.mapping; mapping != nil {
-		if host, existed := h.mapping.Get(addr); existed {
+		if host, existed := h.mapping.Get(ip); existed {
 			return host, true
 		}
 	}
@@ -79,9 +74,9 @@ func (h *ResolverEnhancer) FindHostByIP(ip net.IP) (string, bool) {
 	return "", false
 }
 
-func (h *ResolverEnhancer) InsertHostByIP(ip net.IP, host string) {
+func (h *ResolverEnhancer) InsertHostByIP(ip netip.Addr, host string) {
 	if mapping := h.mapping; mapping != nil {
-		h.mapping.Set(nnip.IpToAddr(ip), host)
+		h.mapping.Set(ip, host)
 	}
 }
 

dns/filters.go

@@ -1,18 +1,19 @@
 package dns
 
 import (
+	"net/netip"
+
 	"github.com/Dreamacro/clash/component/geodata"
 	"github.com/Dreamacro/clash/component/geodata/router"
 	"github.com/Dreamacro/clash/component/mmdb"
 	"github.com/Dreamacro/clash/component/trie"
 	C "github.com/Dreamacro/clash/constant"
 	"github.com/Dreamacro/clash/log"
-	"net"
 	"strings"
 )
 
 type fallbackIPFilter interface {
-	Match(net.IP) bool
+	Match(netip.Addr) bool
 }
 
 type geoipFilter struct {
@@ -21,9 +22,9 @@ type geoipFilter struct {
 
 var geoIPMatcher *router.GeoIPMatcher
 
-func (gf *geoipFilter) Match(ip net.IP) bool {
+func (gf *geoipFilter) Match(ip netip.Addr) bool {
 	if !C.GeodataMode {
-		record, _ := mmdb.Instance().Country(ip)
+		record, _ := mmdb.Instance().Country(ip.AsSlice())
 		return !strings.EqualFold(record.Country.IsoCode, gf.code) && !ip.IsPrivate()
 	}
 
@@ -54,14 +55,14 @@ func (gf *geoipFilter) Match(ip net.IP) bool {
 			return false
 		}
 	}
-	return !geoIPMatcher.Match(ip)
+	return !geoIPMatcher.Match(ip.AsSlice())
 }
 
 type ipnetFilter struct {
-	ipnet *net.IPNet
+	ipnet *netip.Prefix
 }
 
-func (inf *ipnetFilter) Match(ip net.IP) bool {
+func (inf *ipnetFilter) Match(ip netip.Addr) bool {
 	return inf.ipnet.Contains(ip)
 }
 
@@ -76,7 +77,7 @@ type domainFilter struct {
 func NewDomainFilter(domains []string) *domainFilter {
 	df := domainFilter{tree: trie.New[bool]()}
 	for _, domain := range domains {
-		df.tree.Insert(domain, true)
+		_ = df.tree.Insert(domain, true)
 	}
 	return &df
 }

dns/middleware.go

@@ -1,7 +1,6 @@
 package dns
 
 import (
-	"net"
 	"net/netip"
 	"strings"
 	"time"
@@ -88,21 +87,21 @@ func withMapping(mapping *cache.LruCache[netip.Addr, string]) middleware {
 			host := strings.TrimRight(q.Name, ".")
 
 			for _, ans := range msg.Answer {
-				var ip net.IP
+				var ip netip.Addr
 				var ttl uint32
 
 				switch a := ans.(type) {
 				case *D.A:
-					ip = a.A
+					ip = nnip.IpToAddr(a.A)
 					ttl = a.Hdr.Ttl
 				case *D.AAAA:
-					ip = a.AAAA
+					ip = nnip.IpToAddr(a.AAAA)
 					ttl = a.Hdr.Ttl
 				default:
 					continue
 				}
 
-				mapping.SetWithExpire(nnip.IpToAddr(ip), host, time.Now().Add(time.Second*time.Duration(ttl)))
+				mapping.SetWithExpire(ip, host, time.Now().Add(time.Second*time.Duration(ttl)))
 			}
 
 			return msg, nil

dns/resolver.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"math/rand"
-	"net"
 	"net/netip"
 	"strings"
 	"time"
@@ -46,8 +45,8 @@ type Resolver struct {
 }
 
 // ResolveIP request with TypeA and TypeAAAA, priority return TypeA
-func (r *Resolver) ResolveIP(host string) (ip net.IP, err error) {
+func (r *Resolver) ResolveIP(host string) (ip netip.Addr, err error) {
-	ch := make(chan net.IP, 1)
+	ch := make(chan netip.Addr, 1)
 	go func() {
 		defer close(ch)
 		ip, err := r.resolveIP(host, D.TypeAAAA)
@@ -64,23 +63,23 @@ func (r *Resolver) ResolveIP(host string) (ip net.IP, err error) {
 
 	ip, open := <-ch
 	if !open {
-		return nil, resolver.ErrIPNotFound
+		return netip.Addr{}, resolver.ErrIPNotFound
 	}
 
 	return ip, nil
 }
 
 // ResolveIPv4 request with TypeA
-func (r *Resolver) ResolveIPv4(host string) (ip net.IP, err error) {
+func (r *Resolver) ResolveIPv4(host string) (ip netip.Addr, err error) {
 	return r.resolveIP(host, D.TypeA)
 }
 
 // ResolveIPv6 request with TypeAAAA
-func (r *Resolver) ResolveIPv6(host string) (ip net.IP, err error) {
+func (r *Resolver) ResolveIPv6(host string) (ip netip.Addr, err error) {
 	return r.resolveIP(host, D.TypeAAAA)
 }
 
-func (r *Resolver) shouldIPFallback(ip net.IP) bool {
+func (r *Resolver) shouldIPFallback(ip netip.Addr) bool {
 	for _, filter := range r.fallbackIPFilters {
 		if filter.Match(ip) {
 			return true
@@ -101,10 +100,10 @@ func (r *Resolver) ExchangeContext(ctx context.Context, m *D.Msg) (msg *D.Msg, e
 	}
 
 	q := m.Question[0]
-	cache, expireTime, hit := r.lruCache.GetWithExpire(q.String())
+	cacheM, expireTime, hit := r.lruCache.GetWithExpire(q.String())
 	if hit {
 		now := time.Now()
-		msg = cache.Copy()
+		msg = cacheM.Copy()
 		if expireTime.Before(now) {
 			setMsgTTL(msg, uint32(1)) // Continue fetch
 			go r.exchangeWithoutCache(ctx, m)
@@ -255,16 +254,16 @@ func (r *Resolver) ipExchange(ctx context.Context, m *D.Msg) (msg *D.Msg, err er
 	return
 }
 
-func (r *Resolver) resolveIP(host string, dnsType uint16) (ip net.IP, err error) {
+func (r *Resolver) resolveIP(host string, dnsType uint16) (ip netip.Addr, err error) {
-	ip = net.ParseIP(host)
+	ip, err = netip.ParseAddr(host)
-	if ip != nil {
+	if err == nil {
-		isIPv4 := ip.To4() != nil
+		isIPv4 := ip.Is4()
 		if dnsType == D.TypeAAAA && !isIPv4 {
 			return ip, nil
 		} else if dnsType == D.TypeA && isIPv4 {
 			return ip, nil
 		} else {
-			return nil, resolver.ErrIPVersion
+			return netip.Addr{}, resolver.ErrIPVersion
 		}
 	}
 
@@ -273,13 +272,13 @@ func (r *Resolver) resolveIP(host string, dnsType uint16) (ip net.IP, err error)
 
 	msg, err := r.Exchange(query)
 	if err != nil {
-		return nil, err
+		return netip.Addr{}, err
 	}
 
 	ips := msgToIP(msg)
 	ipLength := len(ips)
 	if ipLength == 0 {
-		return nil, resolver.ErrIPNotFound
+		return netip.Addr{}, resolver.ErrIPNotFound
 	}
 
 	ip = ips[rand.Intn(ipLength)]
@@ -318,7 +317,7 @@ type NameServer struct {
 type FallbackFilter struct {
 	GeoIP     bool
 	GeoIPCode string
-	IPCIDR    []*net.IPNet
+	IPCIDR    []*netip.Prefix
 	Domain    []string
 	GeoSite   []*router.DomainMatcher
 }
@@ -359,7 +358,7 @@ func NewResolver(config Config) *Resolver {
 	if len(config.Policy) != 0 {
 		r.policy = trie.New[*Policy]()
 		for domain, nameserver := range config.Policy {
-			r.policy.Insert(domain, NewPolicy(transform([]NameServer{nameserver}, defaultResolver)))
+			_ = r.policy.Insert(domain, NewPolicy(transform([]NameServer{nameserver}, defaultResolver)))
 		}
 	}
 

dns/util.go

@@ -5,9 +5,11 @@ import (
 	"crypto/tls"
 	"fmt"
 	"net"
+	"net/netip"
 	"time"
 
 	"github.com/Dreamacro/clash/common/cache"
+	"github.com/Dreamacro/clash/common/nnip"
 	"github.com/Dreamacro/clash/component/dialer"
 	C "github.com/Dreamacro/clash/constant"
 	"github.com/Dreamacro/clash/log"
@@ -99,15 +101,15 @@ func handleMsgWithEmptyAnswer(r *D.Msg) *D.Msg {
 	return msg
 }
 
-func msgToIP(msg *D.Msg) []net.IP {
+func msgToIP(msg *D.Msg) []netip.Addr {
-	ips := []net.IP{}
+	ips := []netip.Addr{}
 
 	for _, answer := range msg.Answer {
 		switch ans := answer.(type) {
 		case *D.AAAA:
-			ips = append(ips, ans.AAAA)
+			ips = append(ips, nnip.IpToAddr(ans.AAAA))
 		case *D.A:
-			ips = append(ips, ans.A)
+			ips = append(ips, nnip.IpToAddr(ans.A))
 		}
 	}
 
@@ -132,7 +134,7 @@ func (wpc *wrapPacketConn) RemoteAddr() net.Addr {
 	return wpc.rAddr
 }
 
-func dialContextWithProxyAdapter(ctx context.Context, adapterName string, network string, dstIP net.IP, port string, opts ...dialer.Option) (net.Conn, error) {
+func dialContextWithProxyAdapter(ctx context.Context, adapterName string, network string, dstIP netip.Addr, port string, opts ...dialer.Option) (net.Conn, error) {
 	adapter, ok := tunnel.Proxies()[adapterName]
 	if !ok {
 		return nil, fmt.Errorf("proxy adapter [%s] not found", adapterName)
@@ -147,7 +149,7 @@ func dialContextWithProxyAdapter(ctx context.Context, adapterName string, networ
 	}
 
 	addrType := C.AtypIPv4
-	if dstIP.To4() == nil {
+	if dstIP.Is6() {
 		addrType = C.AtypIPv6
 	}
 

listener/tun/ipstack/system/stack.go

@@ -83,6 +83,7 @@ func New(device device.Device, dnsHijack []netip.AddrPort, tunAddress netip.Pref
 			lAddr := conn.LocalAddr().(*net.TCPAddr)
 			rAddr := conn.RemoteAddr().(*net.TCPAddr)
 
+			lAddrPort := netip.AddrPortFrom(nnip.IpToAddr(lAddr.IP), uint16(lAddr.Port))
 			rAddrPort := netip.AddrPortFrom(nnip.IpToAddr(rAddr.IP), uint16(rAddr.Port))
 
 			if rAddrPort.Addr().IsLoopback() {
@@ -135,8 +136,8 @@ func New(device device.Device, dnsHijack []netip.AddrPort, tunAddress netip.Pref
 			metadata := &C.Metadata{
 				NetWork:  C.TCP,
 				Type:     C.TUN,
-				SrcIP:    lAddr.IP,
+				SrcIP:    lAddrPort.Addr(),
-				DstIP:    rAddr.IP,
+				DstIP:    rAddrPort.Addr(),
 				SrcPort:  strconv.Itoa(lAddr.Port),
 				DstPort:  strconv.Itoa(rAddr.Port),
 				AddrType: C.AtypIPv4,

listener/tun/tun_adapter.go

@@ -50,7 +50,7 @@ func New(tunConf *config.Tun, dnsConf *config.DNS, tcpIn chan<- C.ConnContext, u
 		tunAddress = netip.MustParsePrefix("198.18.0.1/16")
 	}
 
-	process.AppendLocalIPs(tunAddress.Masked().Addr().Next().AsSlice())
+	process.AppendLocalIPs(tunAddress.Masked().Addr().Next())
 
 	// open tun device
 	tunDevice, err = parseDevice(devName, uint32(mtu))

rule/common/base.go

@@ -2,7 +2,7 @@ package common
 
 import (
 	"errors"
-	"net"
+	"net/netip"
 	"strings"
 
 	C "github.com/Dreamacro/clash/constant"
@@ -54,17 +54,17 @@ func FindNetwork(params []string) C.NetWork {
 	return C.ALLNet
 }
 
-func FindSourceIPs(params []string) []*net.IPNet {
+func FindSourceIPs(params []string) []*netip.Prefix {
-	var ips []*net.IPNet
+	var ips []*netip.Prefix
 	for _, p := range params {
 		if p == noResolve || len(p) < 7 {
 			continue
 		}
-		_, ipnet, err := net.ParseCIDR(p)
+		ipnet, err := netip.ParsePrefix(p)
 		if err != nil {
 			continue
 		}
-		ips = append(ips, ipnet)
+		ips = append(ips, &ipnet)
 	}
 
 	if len(ips) > 0 {

rule/common/geoip.go

@@ -26,7 +26,7 @@ func (g *GEOIP) RuleType() C.RuleType {
 
 func (g *GEOIP) Match(metadata *C.Metadata) bool {
 	ip := metadata.DstIP
-	if ip == nil {
+	if !ip.IsValid() {
 		return false
 	}
 
@@ -39,10 +39,10 @@ func (g *GEOIP) Match(metadata *C.Metadata) bool {
 			resolver.IsFakeBroadcastIP(ip)
 	}
 	if !C.GeodataMode {
-		record, _ := mmdb.Instance().Country(ip)
+		record, _ := mmdb.Instance().Country(ip.AsSlice())
 		return strings.EqualFold(record.Country.IsoCode, g.country)
 	}
-	return g.geoIPMatcher.Match(ip)
+	return g.geoIPMatcher.Match(ip.AsSlice())
 }
 
 func (g *GEOIP) Adapter() string {

rule/common/ipcidr.go

@@ -1,7 +1,7 @@
 package common
 
 import (
-	"net"
+	"net/netip"
 
 	C "github.com/Dreamacro/clash/constant"
 )
@@ -22,7 +22,7 @@ func WithIPCIDRNoResolve(noResolve bool) IPCIDROption {
 
 type IPCIDR struct {
 	*Base
-	ipnet       *net.IPNet
+	ipnet       *netip.Prefix
 	adapter     string
 	isSourceIP  bool
 	noResolveIP bool
@@ -40,7 +40,7 @@ func (i *IPCIDR) Match(metadata *C.Metadata) bool {
 	if i.isSourceIP {
 		ip = metadata.SrcIP
 	}
-	return ip != nil && i.ipnet.Contains(ip)
+	return ip.IsValid() && i.ipnet.Contains(ip)
 }
 
 func (i *IPCIDR) Adapter() string {
@@ -56,14 +56,14 @@ func (i *IPCIDR) ShouldResolveIP() bool {
 }
 
 func NewIPCIDR(s string, adapter string, opts ...IPCIDROption) (*IPCIDR, error) {
-	_, ipnet, err := net.ParseCIDR(s)
+	ipnet, err := netip.ParsePrefix(s)
 	if err != nil {
 		return nil, errPayload
 	}
 
 	ipcidr := &IPCIDR{
 		Base:    &Base{},
-		ipnet:   ipnet,
+		ipnet:   &ipnet,
 		adapter: adapter,
 	}
 

rule/provider/ipcidr_strategy.go

@@ -13,7 +13,7 @@ type ipcidrStrategy struct {
 }
 
 func (i *ipcidrStrategy) Match(metadata *C.Metadata) bool {
-	return i.trie != nil && i.trie.IsContain(metadata.DstIP)
+	return i.trie != nil && i.trie.IsContain(metadata.DstIP.AsSlice())
 }
 
 func (i *ipcidrStrategy) Count() int {

transport/socks4/socks4.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"io"
 	"net"
+	"net/netip"
 	"strconv"
 
 	"github.com/Dreamacro/clash/component/auth"
@@ -40,6 +41,8 @@ var (
 	ErrRequestUnknownCode      = errors.New("request failed with unknown code")
 )
 
+var subnet = netip.PrefixFrom(netip.IPv4Unspecified(), 24)
+
 func ServerHandshake(rw io.ReadWriter, authenticator auth.Authenticator) (addr string, command Command, err error) {
 	var req [8]byte
 	if _, err = io.ReadFull(rw, req[:]); err != nil {
@@ -57,7 +60,7 @@ func ServerHandshake(rw io.ReadWriter, authenticator auth.Authenticator) (addr s
 	}
 
 	var (
-		dstIP   = req[4:8] // [4]byte
+		dstIP   = netip.AddrFrom4(*(*[4]byte)(req[4:8])) // [4]byte
 		dstPort = req[2:4]                               // [2]byte
 	)
 
@@ -83,7 +86,7 @@ func ServerHandshake(rw io.ReadWriter, authenticator auth.Authenticator) (addr s
 	if host != "" {
 		addr = net.JoinHostPort(host, port)
 	} else {
-		addr = net.JoinHostPort(net.IP(dstIP).String(), port)
+		addr = net.JoinHostPort(dstIP.String(), port)
 	}
 
 	// SOCKS4 only support USERID auth.
@@ -97,7 +100,7 @@ func ServerHandshake(rw io.ReadWriter, authenticator auth.Authenticator) (addr s
 	var reply [8]byte
 	reply[0] = 0x00 // reply code
 	reply[1] = code // result code
-	copy(reply[4:8], dstIP)
+	copy(reply[4:8], dstIP.AsSlice())
 	copy(reply[2:4], dstPort)
 
 	_, wErr := rw.Write(reply[:])
@@ -118,20 +121,18 @@ func ClientHandshake(rw io.ReadWriter, addr string, command Command, userID stri
 		return err
 	}
 
-	ip := net.ParseIP(host)
+	dstIP, err := netip.ParseAddr(host)
-	if ip == nil /* HOST */ {
+	if err != nil /* HOST */ {
-		ip = net.IPv4(0, 0, 0, 1).To4()
+		dstIP = netip.AddrFrom4([4]byte{0, 0, 0, 1})
-	} else if ip.To4() == nil /* IPv6 */ {
+	} else if dstIP.Is6() /* IPv6 */ {
 		return errIPv6NotSupported
 	}
 
-	dstIP := ip.To4()
-
 	req := &bytes.Buffer{}
 	req.WriteByte(Version)
 	req.WriteByte(command)
-	binary.Write(req, binary.BigEndian, uint16(port))
+	_ = binary.Write(req, binary.BigEndian, uint16(port))
-	req.Write(dstIP)
+	req.Write(dstIP.AsSlice())
 	req.WriteString(userID)
 	req.WriteByte(0) /* NULL */
 
@@ -174,12 +175,7 @@ func ClientHandshake(rw io.ReadWriter, addr string, command Command, userID stri
 // Internet Assigned Numbers Authority -- such an address is inadmissible
 // as a destination IP address and thus should never occur if the client
 // can resolve the domain name.)
-func isReservedIP(ip net.IP) bool {
+func isReservedIP(ip netip.Addr) bool {
-	subnet := net.IPNet{
-		IP:   net.IPv4zero,
-		Mask: net.IPv4Mask(0xff, 0xff, 0xff, 0x00),
-	}
-
 	return !ip.IsUnspecified() && subnet.Contains(ip)
 }
 

tunnel/tunnel.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	P "github.com/Dreamacro/clash/component/process"
 	"net"
+	"net/netip"
 	"path/filepath"
 	"runtime"
 	"strconv"
@@ -131,15 +132,15 @@ func process() {
 }
 
 func needLookupIP(metadata *C.Metadata) bool {
-	return resolver.MappingEnabled() && metadata.Host == "" && metadata.DstIP != nil
+	return resolver.MappingEnabled() && metadata.Host == "" && metadata.DstIP.IsValid()
 }
 
 func preHandleMetadata(metadata *C.Metadata) error {
 	// handle IP string on host
-	if ip := net.ParseIP(metadata.Host); ip != nil {
+	if ip, err := netip.ParseAddr(metadata.Host); err == nil {
 		metadata.DstIP = ip
 		metadata.Host = ""
-		if ip.To4() != nil {
+		if ip.Is4() {
 			metadata.AddrType = C.AtypIPv4
 		} else {
 			metadata.AddrType = C.AtypIPv6
@@ -154,11 +155,11 @@ func preHandleMetadata(metadata *C.Metadata) error {
 			metadata.AddrType = C.AtypDomainName
 			metadata.DNSMode = C.DNSMapping
 			if resolver.FakeIPEnabled() {
-				metadata.DstIP = nil
+				metadata.DstIP = netip.Addr{}
 				metadata.DNSMode = C.DNSFakeIP
 			} else if node := resolver.DefaultHosts.Search(host); node != nil {
 				// redir-host should lookup the hosts
-				metadata.DstIP = node.Data.AsSlice()
+				metadata.DstIP = node.Data
 			}
 		} else if resolver.IsFakeIP(metadata.DstIP) {
 			return fmt.Errorf("fake DNS record %s missing", metadata.DstIP)
@@ -351,7 +352,7 @@ func handleTCPConn(connCtx C.ConnContext) {
 }
 
 func shouldResolveIP(rule C.Rule, metadata *C.Metadata) bool {
-	return rule.ShouldResolveIP() && metadata.Host != "" && metadata.DstIP == nil
+	return rule.ShouldResolveIP() && metadata.Host != "" && !metadata.DstIP.IsValid()
 }
 
 func match(metadata *C.Metadata) (C.Proxy, C.Rule, error) {
@@ -360,7 +361,7 @@ func match(metadata *C.Metadata) (C.Proxy, C.Rule, error) {
 	var resolved bool
 
 	if node := resolver.DefaultHosts.Search(metadata.Host); node != nil {
-		metadata.DstIP = node.Data.AsSlice()
+		metadata.DstIP = node.Data
 		resolved = true
 	}