diff --git a/go.mod b/go.mod
index 473ac94..8176bfd 100644
--- a/go.mod
+++ b/go.mod
@@ -7,12 +7,12 @@ require (
 	github.com/dgryski/go-camellia v0.0.0-20191119043421-69a8a13fb23d
 	github.com/dgryski/go-idea v0.0.0-20170306091226-d2fb45a411fb
 	github.com/dgryski/go-rc2 v0.0.0-20150621095337-8a9021637152
-	github.com/insomniacslk/dhcp v0.0.0-20211209223715-7d93572ebe8e
+	github.com/insomniacslk/dhcp v0.0.0-20211214070828-5297eed8f489
 	github.com/nadoo/conflag v0.2.3
 	github.com/nadoo/ipset v0.3.0
 	github.com/xtaci/kcp-go/v5 v5.6.1
-	golang.org/x/crypto v0.0.0-20211209193657-4570a0811e8b
-	golang.org/x/sys v0.0.0-20211210111614-af8b64212486
+	golang.org/x/crypto v0.0.0-20211215153901-e495a2d5b3d3
+	golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e
 )
 
 require (
@@ -26,7 +26,7 @@ require (
 	github.com/templexxx/xorsimd v0.4.1 // indirect
 	github.com/tjfoc/gmsm v1.4.1 // indirect
 	github.com/u-root/uio v0.0.0-20210528151154-e40b768296a7 // indirect
-	golang.org/x/net v0.0.0-20211209124913-491a49abca63 // indirect
+	golang.org/x/net v0.0.0-20211216030914-fe4d6282115f // indirect
 )
 
 // Replace dependency modules with local developing copy
diff --git a/go.sum b/go.sum
index 00b9bcd..26f07f5 100644
--- a/go.sum
+++ b/go.sum
@@ -39,8 +39,8 @@ github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/
 github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
 github.com/hugelgupf/socketpair v0.0.0-20190730060125-05d35a94e714 h1:/jC7qQFrv8CrSJVmaolDVOxTfS9kc36uB6H40kdbQq8=
 github.com/hugelgupf/socketpair v0.0.0-20190730060125-05d35a94e714/go.mod h1:2Goc3h8EklBH5mspfHFxBnEoURQCGzQQH1ga9Myjvis=
-github.com/insomniacslk/dhcp v0.0.0-20211209223715-7d93572ebe8e h1:IQpunlq7T+NiJJMO7ODYV2YWBiv/KnObR3gofX0mWOo=
-github.com/insomniacslk/dhcp v0.0.0-20211209223715-7d93572ebe8e/go.mod h1:h+MxyHxRg9NH3terB1nfRIUaQEcI0XOVkdR9LNBlp8E=
+github.com/insomniacslk/dhcp v0.0.0-20211214070828-5297eed8f489 h1:jhdHqd7DxBrzfuFSoPxjD6nUVaV/1RIn9aHA0WCf/as=
+github.com/insomniacslk/dhcp v0.0.0-20211214070828-5297eed8f489/go.mod h1:h+MxyHxRg9NH3terB1nfRIUaQEcI0XOVkdR9LNBlp8E=
 github.com/jsimonetti/rtnetlink v0.0.0-20190606172950-9527aa82566a/go.mod h1:Oz+70psSo5OFh8DBl0Zv2ACw7Esh6pPUphlvZG9x7uw=
 github.com/jsimonetti/rtnetlink v0.0.0-20200117123717-f846d4f6c1f4/go.mod h1:WGuG/smIU4J/54PblvSbh+xvCZmpJnFgr3ds6Z55XMQ=
 github.com/jsimonetti/rtnetlink v0.0.0-20201009170750-9c6f07d100c1/go.mod h1:hqoO/u39cqLeBLebZ8fWdE96O7FxrAsRYhnVOdgHxok=
@@ -105,8 +105,8 @@ golang.org/x/crypto v0.0.0-20191219195013-becbf705a915/go.mod h1:LzIPMQfyMNhhGPh
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20200728195943-123391ffb6de/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20201012173705-84dcc777aaee/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/crypto v0.0.0-20211209193657-4570a0811e8b h1:QAqMVf3pSa6eeTsuklijukjXBlj7Es2QQplab+/RbQ4=
-golang.org/x/crypto v0.0.0-20211209193657-4570a0811e8b/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
+golang.org/x/crypto v0.0.0-20211215153901-e495a2d5b3d3 h1:0es+/5331RGQPcXlMfP+WrnIIS6dNnNRe0WB02W0F4M=
+golang.org/x/crypto v0.0.0-20211215153901-e495a2d5b3d3/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
 golang.org/x/lint v0.0.0-20190227174305-5b3e6a55c961/go.mod h1:wehouNa3lNwaWXcvxsM5YxQ5yQlVC4a0KAMCusXpPoU=
@@ -130,8 +130,8 @@ golang.org/x/net v0.0.0-20200707034311-ab3426394381/go.mod h1:/O7V0waA8r7cgGh81R
 golang.org/x/net v0.0.0-20201010224723-4f7140c49acb/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/net v0.0.0-20201110031124-69a78807bb2b/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
-golang.org/x/net v0.0.0-20211209124913-491a49abca63 h1:iocB37TsdFuN6IBRZ+ry36wrkoV51/tl5vOWqkcPGvY=
-golang.org/x/net v0.0.0-20211209124913-491a49abca63/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/net v0.0.0-20211216030914-fe4d6282115f h1:hEYJvxw1lSnWIl8X9ofsYMklzaDs90JI2az5YMd4fPM=
+golang.org/x/net v0.0.0-20211216030914-fe4d6282115f/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -157,8 +157,8 @@ golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210525143221-35b2ab0089ea/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20211210111614-af8b64212486 h1:5hpz5aRr+W1erYCL5JRhSUBJRph7l9XkNveoExlrKYk=
-golang.org/x/sys v0.0.0-20211210111614-af8b64212486/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e h1:fLOSk5Q00efkSvAm+4xcoXD+RRmLmmulPn5I3Y9F2EM=
+golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1 h1:v+OssWQX+hTHEmOBgwxdZxK4zHq3yOs8F9J7mk0PY8E=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
diff --git a/proxy/http/server.go b/proxy/http/server.go
index 2c28489..0613bbe 100644
--- a/proxy/http/server.go
+++ b/proxy/http/server.go
@@ -42,13 +42,13 @@ func (s *HTTP) ListenAndServe() {
 
 // Serve serves a connection.
 func (s *HTTP) Serve(cc net.Conn) {
-	defer cc.Close()
-
 	if c, ok := cc.(*net.TCPConn); ok {
 		c.SetKeepAlive(true)
 	}
 
 	c := proxy.NewConn(cc)
+	defer c.Close()
+
 	req, err := parseRequest(c.Reader())
 	if err != nil {
 		log.F("[http] can not parse request from %s, error: %v", c.RemoteAddr(), err)
diff --git a/proxy/mixed/mixed.go b/proxy/mixed/mixed.go
index 3ba58f4..199dbeb 100644
--- a/proxy/mixed/mixed.go
+++ b/proxy/mixed/mixed.go
@@ -1,7 +1,6 @@
 package mixed
 
 import (
-	"bytes"
 	"net"
 	"net/url"
 
@@ -80,37 +79,12 @@ func (m *Mixed) ListenAndServe() {
 
 // Serve serves connections.
 func (m *Mixed) Serve(c net.Conn) {
-	defer c.Close()
-
-	if c, ok := c.(*net.TCPConn); ok {
-		c.SetKeepAlive(true)
-	}
-
-	cc := proxy.NewConn(c)
-	head, err := cc.Peek(1)
-	if err != nil {
-		// log.F("[mixed] socks5 peek error: %s", err)
-		return
-	}
-
-	// check socks5, client send socksversion: 5 as the first byte
-	if head[0] == socks5.Version {
-		m.socks5Server.Serve(cc)
-		return
-	}
-
-	head, err = cc.Peek(8)
-	if err != nil {
-		log.F("[mixed] http peek error: %s", err)
-		return
-	}
-
-	for _, method := range http.Methods {
-		if bytes.HasPrefix(head, method) {
-			m.httpServer.Serve(cc)
+	conn := proxy.NewConn(c)
+	if head, err := conn.Peek(1); err == nil {
+		if head[0] == socks5.Version {
+			m.socks5Server.Serve(conn)
 			return
 		}
 	}
-
-	log.F("[mixed] unknown request from %s, ignored", c.RemoteAddr())
+	m.httpServer.Serve(conn)
 }
diff --git a/systemd/glider@.service b/systemd/glider@.service
index 20840bd..92cbb06 100644
--- a/systemd/glider@.service
+++ b/systemd/glider@.service
@@ -4,7 +4,7 @@ After=network.target iptables.service ip6tables.service
 
 [Service]
 Type=simple
-User=nobody
+DynamicUser=yes
 Restart=always
 LimitNOFILE=102400