Merge pull request #109 from apernet/wip-io-rst

feat: io tcp reset support (forward only)
refactor(io): nft/ipt generator func
2024-03-21 18:43:43 -07:00 · 2024-03-22 02:04:25 +08:00 · 2024-03-20 19:01:26 -07:00 · 2024-03-20 18:41:45 -07:00 · 2024-03-20 18:40:49 -07:00 · 2024-03-20 18:39:05 -07:00
20 changed files with 617 additions and 262 deletions
--- a/.github/workflows/check.yaml
+++ b/.github/workflows/check.yaml
@@ -0,0 +1,47 @@
+name: Quality check
+on:
+  push:
+    branches:
+    - "*"
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  static-analysis:
+    name: Static analysis
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: 'stable'
+
+      - run: go vet ./...
+
+      - name: staticcheck
+        uses: dominikh/staticcheck-action@v1.3.0
+        with:
+          install-go: false
+
+  tests:
+    name: Tests
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: 'stable'
+
+      - run: go test ./...
--- a/.github/workflows/release.yaml
+++ b/.github/workflows/release.yaml
@@ -1,6 +1,7 @@
+name: Release
 on:
  release:
-    types: [ created ]
+    types: [published]

 permissions:
  contents: write
@@ -12,8 +13,8 @@ jobs:
    runs-on: ubuntu-latest
    strategy:
      matrix:
-        goos: [ linux ]
-        goarch: [ "386", amd64, arm64 ]
+        goos: [linux]
+        goarch: ["386", amd64, arm64]
    steps:
      - uses: actions/checkout@v4
      - uses: wangyoucao577/go-release-action@v1
@@ -21,6 +22,6 @@ jobs:
          github_token: ${{ secrets.GITHUB_TOKEN }}
          goos: ${{ matrix.goos }}
          goarch: ${{ matrix.goarch }}
-          goversion: "https://go.dev/dl/go1.21.6.linux-amd64.tar.gz"
+          goversion: "https://go.dev/dl/go1.22.0.linux-amd64.tar.gz"
          binary_name: "OpenGFW"
-          extra_files: LICENSE README.md README.zh.md
+          extra_files: LICENSE README.md README.zh.md
--- a/README.ja.md
+++ b/README.ja.md
@@ -1,5 +1,6 @@
 # ![OpenGFW](docs/logo.png)

+[![Quality check status](https://github.com/apernet/OpenGFW/actions/workflows/check.yaml/badge.svg)](https://github.com/apernet/OpenGFW/actions/workflows/check.yaml)
 [![License][1]][2]

 [1]: https://img.shields.io/badge/License-MPL_2.0-brightgreen.svg
@@ -19,8 +20,8 @@ Telegram グループ: https://t.me/OpGFW

 - フル IP/TCP 再アセンブル、各種プロトコルアナライザー
  - HTTP、TLS、QUIC、DNS、SSH、SOCKS4/5、WireGuard、その他多数
-  - Shadowsocks の「完全に暗号化されたトラフィック」の検出など (https://gfw.report/publications/usenixsecurity23/data/paper/paper.pdf)
-  - トロイの木馬キラー (https://github.com/XTLS/Trojan-killer) に基づくトロイの木馬 (プロキシプロトコル) 検出
+  - Shadowsocks の「完全に暗号化されたトラフィック」の検出など (https://gfw.report/publications/usenixsecurity23/en/)
+  - Trojan プロキシプロトコルの検出
  - [WIP] 機械学習に基づくトラフィック分類
 - IPv4 と IPv6 をフルサポート
 - フローベースのマルチコア負荷分散
@@ -62,7 +63,11 @@ OpenGFW は OpenWrt 23.05 で動作することがテストされています（
 依存関係をインストールしてください：

 ```shell
+# バージョン22.03以降（nftables をベースとしたファイアウォール）の場合
 opkg install kmod-nft-queue kmod-nf-conntrack-netlink
+
+# バージョン22.03以前（22.03を除く、iptablesをベースとしたファイアウォール）の場合
+opkg install kmod-ipt-nfqueue iptables-mod-nfqueue kmod-nf-conntrack-netlink
 ```

 ### 設定例
@@ -70,7 +75,10 @@ opkg install kmod-nft-queue kmod-nf-conntrack-netlink
 ```yaml
 io:
  queueSize: 1024
+  rcvBuf: 4194304
+  sndBuf: 4194304
  local: true # FORWARD チェーンで OpenGFW を実行したい場合は false に設定する
+  rst: false # ブロックされたTCP接続に対してRSTを送信する場合はtrueに設定してください。local=falseのみです

 workers:
  count: 4
--- a/README.md
+++ b/README.md
@@ -1,5 +1,6 @@
 # ![OpenGFW](docs/logo.png)

+[![Quality check status](https://github.com/apernet/OpenGFW/actions/workflows/check.yaml/badge.svg)](https://github.com/apernet/OpenGFW/actions/workflows/check.yaml)
 [![License][1]][2]

 [1]: https://img.shields.io/badge/License-MPL_2.0-brightgreen.svg
@@ -23,8 +24,8 @@ Telegram group: https://t.me/OpGFW
 - Full IP/TCP reassembly, various protocol analyzers
  - HTTP, TLS, QUIC, DNS, SSH, SOCKS4/5, WireGuard, and many more to come
  - "Fully encrypted traffic" detection for Shadowsocks,
-    etc. (https://gfw.report/publications/usenixsecurity23/data/paper/paper.pdf)
-  - Trojan (proxy protocol) detection based on Trojan-killer (https://github.com/XTLS/Trojan-killer)
+    etc. (https://gfw.report/publications/usenixsecurity23/en/)
+  - Trojan (proxy protocol) detection
  - [WIP] Machine learning based traffic classification
 - Full IPv4 and IPv6 support
 - Flow-based multicore load balancing
@@ -66,7 +67,11 @@ OpenGFW has been tested to work on OpenWrt 23.05 (other versions should also wor
 Install the dependencies:

 ```shell
+# For OpenWrt version 22.03 and later (nftables based firewall)
 opkg install kmod-nft-queue kmod-nf-conntrack-netlink
+
+# For OpenWrt versions prior to 22.03 (excluding 22.03, iptables based firewall)
+opkg install kmod-ipt-nfqueue iptables-mod-nfqueue kmod-nf-conntrack-netlink
 ```

 ### Example config
@@ -74,7 +79,10 @@ opkg install kmod-nft-queue kmod-nf-conntrack-netlink
 ```yaml
 io:
  queueSize: 1024
+  rcvBuf: 4194304
+  sndBuf: 4194304
  local: true # set to false if you want to run OpenGFW on FORWARD chain
+  rst: false # set to true if you want to send RST for blocked TCP connections, local=false only

 workers:
  count: 4
--- a/README.zh.md
+++ b/README.zh.md
@@ -1,5 +1,6 @@
 # ![OpenGFW](docs/logo.png)

+[![Quality check status](https://github.com/apernet/OpenGFW/actions/workflows/check.yaml/badge.svg)](https://github.com/apernet/OpenGFW/actions/workflows/check.yaml)
 [![License][1]][2]

 [1]: https://img.shields.io/badge/License-MPL_2.0-brightgreen.svg
@@ -19,8 +20,8 @@ Telegram 群组： https://t.me/OpGFW

 - 完整的 IP/TCP 重组，各种协议解析器
  - HTTP, TLS, QUIC, DNS, SSH, SOCKS4/5, WireGuard, 更多协议正在开发中
-  - Shadowsocks 等 "全加密流量" 检测 (https://gfw.report/publications/usenixsecurity23/data/paper/paper.pdf)
-  - 基于 Trojan-killer 的 Trojan 检测 (https://github.com/XTLS/Trojan-killer)
+  - Shadowsocks 等 "全加密流量" 检测 (https://gfw.report/publications/usenixsecurity23/zh/)
+  - Trojan 协议检测
  - [开发中] 基于机器学习的流量分类
 - 同等支持 IPv4 和 IPv6
 - 基于流的多核负载均衡
@@ -62,7 +63,11 @@ OpenGFW 在 OpenWrt 23.05 上测试可用（其他版本应该也可以，暂时
 安装依赖：

 ```shell
+# 对于 22.03 或者之后的版本（基于 nftables 的防火墙）
 opkg install kmod-nft-queue kmod-nf-conntrack-netlink
+
+# 对于 22.03 之前的版本（不包括 22.03， 基于 iptables 的防火墙）
+opkg install kmod-ipt-nfqueue iptables-mod-nfqueue kmod-nf-conntrack-netlink
 ```

 ### 样例配置
@@ -70,7 +75,10 @@ opkg install kmod-nft-queue kmod-nf-conntrack-netlink
 ```yaml
 io:
  queueSize: 1024
+  rcvBuf: 4194304
+  sndBuf: 4194304
  local: true # 如果需要在 FORWARD 链上运行 OpenGFW，请设置为 false
+  rst: false # 是否对要阻断的 TCP 连接发送 RST。仅在 local=false 时有效

 workers:
  count: 4
--- a/analyzer/internal/tls.go
+++ b/analyzer/internal/tls.go
@@ -5,7 +5,26 @@ import (
 	"github.com/apernet/OpenGFW/analyzer/utils"
 )

-func ParseTLSClientHello(chBuf *utils.ByteBuffer) analyzer.PropMap {
+// TLS record types.
+const (
+	RecordTypeHandshake = 0x16
+)
+
+// TLS handshake message types.
+const (
+	TypeClientHello = 0x01
+	TypeServerHello = 0x02
+)
+
+// TLS extension numbers.
+const (
+	extServerName           = 0x0000
+	extALPN                 = 0x0010
+	extSupportedVersions    = 0x002b
+	extEncryptedClientHello = 0xfe0d
+)
+
+func ParseTLSClientHelloMsgData(chBuf *utils.ByteBuffer) analyzer.PropMap {
 	var ok bool
 	m := make(analyzer.PropMap)
 	// Version, random & session ID length combined are within 35 bytes,
@@ -76,7 +95,7 @@ func ParseTLSClientHello(chBuf *utils.ByteBuffer) analyzer.PropMap {
 	return m
 }

-func ParseTLSServerHello(shBuf *utils.ByteBuffer) analyzer.PropMap {
+func ParseTLSServerHelloMsgData(shBuf *utils.ByteBuffer) analyzer.PropMap {
 	var ok bool
 	m := make(analyzer.PropMap)
 	// Version, random & session ID length combined are within 35 bytes,
@@ -133,7 +152,7 @@ func ParseTLSServerHello(shBuf *utils.ByteBuffer) analyzer.PropMap {

 func parseTLSExtensions(extType uint16, extDataBuf *utils.ByteBuffer, m analyzer.PropMap) bool {
 	switch extType {
-	case 0x0000: // SNI
+	case extServerName:
 		ok := extDataBuf.Skip(2) // Ignore list length, we only care about the first entry for now
 		if !ok {
 			// Not enough data for list length
@@ -154,7 +173,7 @@ func parseTLSExtensions(extType uint16, extDataBuf *utils.ByteBuffer, m analyzer
 			// Not enough data for SNI
 			return false
 		}
-	case 0x0010: // ALPN
+	case extALPN:
 		ok := extDataBuf.Skip(2) // Ignore list length, as we read until the end
 		if !ok {
 			// Not enough data for list length
@@ -175,7 +194,7 @@ func parseTLSExtensions(extType uint16, extDataBuf *utils.ByteBuffer, m analyzer
 			alpnList = append(alpnList, alpn)
 		}
 		m["alpn"] = alpnList
-	case 0x002b: // Supported Versions
+	case extSupportedVersions:
 		if extDataBuf.Len() == 2 {
 			// Server only selects one version
 			m["supported_versions"], _ = extDataBuf.GetUint16(false, true)
@@ -197,7 +216,7 @@ func parseTLSExtensions(extType uint16, extDataBuf *utils.ByteBuffer, m analyzer
 			}
 			m["supported_versions"] = versions
 		}
-	case 0xfe0d: // ECH
+	case extEncryptedClientHello:
 		// We can't parse ECH for now, just set a flag
 		m["ech"] = true
 	}
--- a/analyzer/tcp/fet.go
+++ b/analyzer/tcp/fet.go
@@ -143,8 +143,11 @@ func isTLSorHTTP(bytes []byte) bool {
 	if len(bytes) < 3 {
 		return false
 	}
-	if bytes[0] == 0x16 && bytes[1] == 0x03 && bytes[2] <= 0x03 {
-		// TLS handshake for TLS 1.0-1.3
+	// "We observe that the GFW exempts any connection whose first
+	// three bytes match the following regular expression:
+	// [\x16-\x17]\x03[\x00-\x09]" - from the paper in Section 4.3
+	if bytes[0] >= 0x16 && bytes[0] <= 0x17 &&
+		bytes[1] == 0x03 && bytes[2] <= 0x09 {
 		return true
 	}
 	// HTTP request
--- a/analyzer/tcp/http_test.go
+++ b/analyzer/tcp/http_test.go
@@ -0,0 +1,64 @@
+package tcp
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/apernet/OpenGFW/analyzer"
+)
+
+func TestHTTPParsing_Request(t *testing.T) {
+	testCases := map[string]analyzer.PropMap{
+		"GET / HTTP/1.1\r\n": {
+			"method": "GET", "path": "/", "version": "HTTP/1.1",
+		},
+		"POST /hello?a=1&b=2 HTTP/1.0\r\n": {
+			"method": "POST", "path": "/hello?a=1&b=2", "version": "HTTP/1.0",
+		},
+		"PUT /world HTTP/1.1\r\nContent-Length: 4\r\n\r\nbody": {
+			"method": "PUT", "path": "/world", "version": "HTTP/1.1", "headers": analyzer.PropMap{"content-length": "4"},
+		},
+		"DELETE /goodbye HTTP/2.0\r\n": {
+			"method": "DELETE", "path": "/goodbye", "version": "HTTP/2.0",
+		},
+	}
+
+	for tc, want := range testCases {
+		t.Run(strings.Split(tc, " ")[0], func(t *testing.T) {
+			tc, want := tc, want
+			t.Parallel()
+
+			u, _ := newHTTPStream(nil).Feed(false, false, false, 0, []byte(tc))
+			got := u.M.Get("req")
+			if !reflect.DeepEqual(got, want) {
+				t.Errorf("\"%s\" parsed = %v, want %v", tc, got, want)
+			}
+		})
+	}
+}
+
+func TestHTTPParsing_Response(t *testing.T) {
+	testCases := map[string]analyzer.PropMap{
+		"HTTP/1.0 200 OK\r\nContent-Length: 4\r\n\r\nbody": {
+			"version": "HTTP/1.0", "status": 200,
+			"headers": analyzer.PropMap{"content-length": "4"},
+		},
+		"HTTP/2.0 204 No Content\r\n\r\n": {
+			"version": "HTTP/2.0", "status": 204,
+		},
+	}
+
+	for tc, want := range testCases {
+		t.Run(strings.Split(tc, " ")[0], func(t *testing.T) {
+			tc, want := tc, want
+			t.Parallel()
+
+			u, _ := newHTTPStream(nil).Feed(true, false, false, 0, []byte(tc))
+			got := u.M.Get("resp")
+			if !reflect.DeepEqual(got, want) {
+				t.Errorf("\"%s\" parsed = %v, want %v", tc, got, want)
+			}
+		})
+	}
+}
--- a/analyzer/tcp/socks.go
+++ b/analyzer/tcp/socks.go
@@ -208,10 +208,10 @@ func (s *socksStream) parseSocks5ReqMethod() utils.LSMAction {
 		switch method {
 		case Socks5AuthNotRequired:
 			s.authReqMethod = Socks5AuthNotRequired
-			break
+			return utils.LSMActionNext
 		case Socks5AuthPassword:
 			s.authReqMethod = Socks5AuthPassword
-			break
+			return utils.LSMActionNext
 		default:
 			// TODO: more auth method to support
 		}
--- a/analyzer/tcp/tls.go
+++ b/analyzer/tcp/tls.go
@@ -44,12 +44,12 @@ type tlsStream struct {
 func newTLSStream(logger analyzer.Logger) *tlsStream {
 	s := &tlsStream{logger: logger, reqBuf: &utils.ByteBuffer{}, respBuf: &utils.ByteBuffer{}}
 	s.reqLSM = utils.NewLinearStateMachine(
-		s.tlsClientHelloSanityCheck,
-		s.parseClientHello,
+		s.tlsClientHelloPreprocess,
+		s.parseClientHelloData,
 	)
 	s.respLSM = utils.NewLinearStateMachine(
-		s.tlsServerHelloSanityCheck,
-		s.parseServerHello,
+		s.tlsServerHelloPreprocess,
+		s.parseServerHelloData,
 	)
 	return s
 }
@@ -89,61 +89,105 @@ func (s *tlsStream) Feed(rev, start, end bool, skip int, data []byte) (u *analyz
 	return update, cancelled || (s.reqDone && s.respDone)
 }

-func (s *tlsStream) tlsClientHelloSanityCheck() utils.LSMAction {
-	data, ok := s.reqBuf.Get(9, true)
+// tlsClientHelloPreprocess validates ClientHello message.
+//
+// During validation, message header and first handshake header may be removed
+// from `s.reqBuf`.
+func (s *tlsStream) tlsClientHelloPreprocess() utils.LSMAction {
+	// headers size: content type (1 byte) + legacy protocol version (2 bytes) +
+	//   + content length (2 bytes) + message type (1 byte) +
+	//   + handshake length (3 bytes)
+	const headersSize = 9
+
+	// minimal data size: protocol version (2 bytes) + random (32 bytes) +
+	//   + session ID (1 byte) + cipher suites (4 bytes) +
+	//   + compression methods (2 bytes) + no extensions
+	const minDataSize = 41
+
+	header, ok := s.reqBuf.Get(headersSize, true)
 	if !ok {
+		// not a full header yet
 		return utils.LSMActionPause
 	}
-	if data[0] != 0x16 || data[5] != 0x01 {
-		// Not a TLS handshake, or not a client hello
+
+	if header[0] != internal.RecordTypeHandshake || header[5] != internal.TypeClientHello {
 		return utils.LSMActionCancel
 	}
-	s.clientHelloLen = int(data[6])<<16 | int(data[7])<<8 | int(data[8])
-	if s.clientHelloLen < 41 {
-		// 2 (Protocol Version) +
-		// 32 (Random) +
-		// 1 (Session ID Length) +
-		// 2 (Cipher Suites Length) +_ws.col.protocol == "TLSv1.3"
-		// 2 (Cipher Suite) +
-		// 1 (Compression Methods Length) +
-		// 1 (Compression Method) +
-		// No extensions
-		// This should be the bare minimum for a client hello
+
+	s.clientHelloLen = int(header[6])<<16 | int(header[7])<<8 | int(header[8])
+	if s.clientHelloLen < minDataSize {
 		return utils.LSMActionCancel
 	}
+
+	// TODO: something is missing. See:
+	//   const messageHeaderSize = 4
+	//   fullMessageLen := int(header[3])<<8 | int(header[4])
+	//   msgNo := fullMessageLen / int(messageHeaderSize+s.serverHelloLen)
+	//   if msgNo != 1 {
+	// 	   // what here?
+	//   }
+	//   if messageNo != int(messageNo) {
+	// 	   // what here?
+	//   }
+
 	return utils.LSMActionNext
 }

-func (s *tlsStream) tlsServerHelloSanityCheck() utils.LSMAction {
-	data, ok := s.respBuf.Get(9, true)
+// tlsServerHelloPreprocess validates ServerHello message.
+//
+// During validation, message header and first handshake header may be removed
+// from `s.reqBuf`.
+func (s *tlsStream) tlsServerHelloPreprocess() utils.LSMAction {
+	// header size: content type (1 byte) + legacy protocol version (2 byte) +
+	//   + content length (2 byte) + message type (1 byte) +
+	//   + handshake length (3 byte)
+	const headersSize = 9
+
+	// minimal data size: server version (2 byte) + random (32 byte) +
+	//	 + session ID (>=1 byte) + cipher suite (2 byte) +
+	//	 + compression method (1 byte) + no extensions
+	const minDataSize = 38
+
+	header, ok := s.respBuf.Get(headersSize, true)
 	if !ok {
+		// not a full header yet
 		return utils.LSMActionPause
 	}
-	if data[0] != 0x16 || data[5] != 0x02 {
-		// Not a TLS handshake, or not a server hello
+
+	if header[0] != internal.RecordTypeHandshake || header[5] != internal.TypeServerHello {
 		return utils.LSMActionCancel
 	}
-	s.serverHelloLen = int(data[6])<<16 | int(data[7])<<8 | int(data[8])
-	if s.serverHelloLen < 38 {
-		// 2 (Protocol Version) +
-		// 32 (Random) +
-		// 1 (Session ID Length) +
-		// 2 (Cipher Suite) +
-		// 1 (Compression Method) +
-		// No extensions
-		// This should be the bare minimum for a server hello
+
+	s.serverHelloLen = int(header[6])<<16 | int(header[7])<<8 | int(header[8])
+	if s.serverHelloLen < minDataSize {
 		return utils.LSMActionCancel
 	}
+
+	// TODO: something is missing. See example:
+	//   const messageHeaderSize = 4
+	//   fullMessageLen := int(header[3])<<8 | int(header[4])
+	//   msgNo := fullMessageLen / int(messageHeaderSize+s.serverHelloLen)
+	//   if msgNo != 1 {
+	// 	   // what here?
+	//   }
+	//   if messageNo != int(messageNo) {
+	// 	   // what here?
+	//   }
+
 	return utils.LSMActionNext
 }

-func (s *tlsStream) parseClientHello() utils.LSMAction {
+// parseClientHelloData converts valid ClientHello message data (without
+// headers) into `analyzer.PropMap`.
+//
+// Parsing error may leave `s.reqBuf` in an unusable state.
+func (s *tlsStream) parseClientHelloData() utils.LSMAction {
 	chBuf, ok := s.reqBuf.GetSubBuffer(s.clientHelloLen, true)
 	if !ok {
 		// Not a full client hello yet
 		return utils.LSMActionPause
 	}
-	m := internal.ParseTLSClientHello(chBuf)
+	m := internal.ParseTLSClientHelloMsgData(chBuf)
 	if m == nil {
 		return utils.LSMActionCancel
 	} else {
@@ -153,13 +197,17 @@ func (s *tlsStream) parseClientHello() utils.LSMAction {
 	}
 }

-func (s *tlsStream) parseServerHello() utils.LSMAction {
+// parseServerHelloData converts valid ServerHello message data (without
+// headers) into `analyzer.PropMap`.
+//
+// Parsing error may leave `s.respBuf` in an unusable state.
+func (s *tlsStream) parseServerHelloData() utils.LSMAction {
 	shBuf, ok := s.respBuf.GetSubBuffer(s.serverHelloLen, true)
 	if !ok {
 		// Not a full server hello yet
 		return utils.LSMActionPause
 	}
-	m := internal.ParseTLSServerHello(shBuf)
+	m := internal.ParseTLSServerHelloMsgData(shBuf)
 	if m == nil {
 		return utils.LSMActionCancel
 	} else {
--- a/analyzer/tcp/tls_test.go
+++ b/analyzer/tcp/tls_test.go
@@ -0,0 +1,69 @@
+package tcp
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/apernet/OpenGFW/analyzer"
+)
+
+func TestTlsStreamParsing_ClientHello(t *testing.T) {
+	// example packet taken from <https://tls12.xargs.org/#client-hello/annotated>
+	clientHello := []byte{
+		0x16, 0x03, 0x01, 0x00, 0xa5, 0x01, 0x00, 0x00, 0xa1, 0x03, 0x03, 0x00,
+		0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c,
+		0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18,
+		0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x00, 0x00, 0x20, 0xcc, 0xa8,
+		0xcc, 0xa9, 0xc0, 0x2f, 0xc0, 0x30, 0xc0, 0x2b, 0xc0, 0x2c, 0xc0, 0x13,
+		0xc0, 0x09, 0xc0, 0x14, 0xc0, 0x0a, 0x00, 0x9c, 0x00, 0x9d, 0x00, 0x2f,
+		0x00, 0x35, 0xc0, 0x12, 0x00, 0x0a, 0x01, 0x00, 0x00, 0x58, 0x00, 0x00,
+		0x00, 0x18, 0x00, 0x16, 0x00, 0x00, 0x13, 0x65, 0x78, 0x61, 0x6d, 0x70,
+		0x6c, 0x65, 0x2e, 0x75, 0x6c, 0x66, 0x68, 0x65, 0x69, 0x6d, 0x2e, 0x6e,
+		0x65, 0x74, 0x00, 0x05, 0x00, 0x05, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x0a, 0x00, 0x0a, 0x00, 0x08, 0x00, 0x1d, 0x00, 0x17, 0x00, 0x18, 0x00,
+		0x19, 0x00, 0x0b, 0x00, 0x02, 0x01, 0x00, 0x00, 0x0d, 0x00, 0x12, 0x00,
+		0x10, 0x04, 0x01, 0x04, 0x03, 0x05, 0x01, 0x05, 0x03, 0x06, 0x01, 0x06,
+		0x03, 0x02, 0x01, 0x02, 0x03, 0xff, 0x01, 0x00, 0x01, 0x00, 0x00, 0x12,
+		0x00, 0x00,
+	}
+	want := analyzer.PropMap{
+		"ciphers":     []uint16{52392, 52393, 49199, 49200, 49195, 49196, 49171, 49161, 49172, 49162, 156, 157, 47, 53, 49170, 10},
+		"compression": []uint8{0},
+		"random":      []uint8{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31},
+		"session":     []uint8{},
+		"sni":         "example.ulfheim.net",
+		"version":     uint16(771),
+	}
+
+	s := newTLSStream(nil)
+	u, _ := s.Feed(false, false, false, 0, clientHello)
+	got := u.M.Get("req")
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("%d B parsed = %v, want %v", len(clientHello), got, want)
+	}
+}
+
+func TestTlsStreamParsing_ServerHello(t *testing.T) {
+	// example packet taken from <https://tls12.xargs.org/#server-hello/annotated>
+	serverHello := []byte{
+		0x16, 0x03, 0x03, 0x00, 0x31, 0x02, 0x00, 0x00, 0x2d, 0x03, 0x03, 0x70,
+		0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c,
+		0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88,
+		0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x00, 0xc0, 0x13, 0x00, 0x00,
+		0x05, 0xff, 0x01, 0x00, 0x01, 0x00,
+	}
+	want := analyzer.PropMap{
+		"cipher":      uint16(49171),
+		"compression": uint8(0),
+		"random":      []uint8{112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143},
+		"session":     []uint8{},
+		"version":     uint16(771),
+	}
+
+	s := newTLSStream(nil)
+	u, _ := s.Feed(true, false, false, 0, serverHello)
+	got := u.M.Get("resp")
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("%d B parsed = %v, want %v", len(serverHello), got, want)
+	}
+}
--- a/analyzer/tcp/trojan.go
+++ b/analyzer/tcp/trojan.go
@@ -9,22 +9,14 @@ import (
 var _ analyzer.TCPAnalyzer = (*TrojanAnalyzer)(nil)

 // CCS stands for "Change Cipher Spec"
-var trojanCCS = []byte{20, 3, 3, 0, 1, 1}
+var ccsPattern = []byte{20, 3, 3, 0, 1, 1}

-const (
-	trojanUpLB    = 650
-	trojanUpUB    = 1000
-	trojanDownLB1 = 170
-	trojanDownUB1 = 180
-	trojanDownLB2 = 3000
-	trojanDownUB2 = 7500
-)
-
-// TrojanAnalyzer uses a very simple packet length based check to determine
-// if a TLS connection is actually the Trojan proxy protocol.
-// The algorithm is from the following project, with small modifications:
-// https://github.com/XTLS/Trojan-killer
-// Warning: Experimental only. This method is known to have significant false positives and false negatives.
+// TrojanAnalyzer uses length-based heuristics to detect Trojan traffic based on
+// its "TLS-in-TLS" nature. The heuristics are trained using a decision tree with
+// about 2000 samples. This is highly experimental and is known to have significant
+// false positives (about 9% false positives & 3% false negatives).
+// We do NOT recommend directly blocking all positive connections, as this is likely
+// to break many normal TLS connections.
 type TrojanAnalyzer struct{}

 func (a *TrojanAnalyzer) Name() string {
@@ -32,7 +24,7 @@ func (a *TrojanAnalyzer) Name() string {
 }

 func (a *TrojanAnalyzer) Limit() int {
-	return 16384
+	return 512000
 }

 func (a *TrojanAnalyzer) NewTCP(info analyzer.TCPInfo, logger analyzer.Logger) analyzer.TCPStream {
@@ -40,10 +32,12 @@ func (a *TrojanAnalyzer) NewTCP(info analyzer.TCPInfo, logger analyzer.Logger) a
 }

 type trojanStream struct {
-	logger    analyzer.Logger
-	active    bool
-	upCount   int
-	downCount int
+	logger   analyzer.Logger
+	first    bool
+	count    bool
+	rev      bool
+	seq      [3]int
+	seqIndex int
 }

 func newTrojanStream(logger analyzer.Logger) *trojanStream {
@@ -57,33 +51,47 @@ func (s *trojanStream) Feed(rev, start, end bool, skip int, data []byte) (u *ana
 	if len(data) == 0 {
 		return nil, false
 	}
-	if !rev && !s.active && len(data) >= 6 && bytes.Equal(data[:6], trojanCCS) {
-		// Client CCS encountered, start counting
-		s.active = true
+
+	if s.first {
+		s.first = false
+		// Stop if it's not a valid TLS connection
+		if !(!rev && len(data) >= 3 && data[0] >= 0x16 && data[0] <= 0x17 &&
+			data[1] == 0x03 && data[2] <= 0x09) {
+			return nil, true
+		}
 	}
-	if s.active {
-		if rev {
-			// Down direction
-			s.downCount += len(data)
+
+	if !rev && !s.count && len(data) >= 6 && bytes.Equal(data[:6], ccsPattern) {
+		// Client Change Cipher Spec encountered, start counting
+		s.count = true
+	}
+
+	if s.count {
+		if rev == s.rev {
+			// Same direction as last time, just update the number
+			s.seq[s.seqIndex] += len(data)
 		} else {
-			// Up direction
-			if s.upCount >= trojanUpLB && s.upCount <= trojanUpUB &&
-				((s.downCount >= trojanDownLB1 && s.downCount <= trojanDownUB1) ||
-					(s.downCount >= trojanDownLB2 && s.downCount <= trojanDownUB2)) {
+			// Different direction, bump the index
+			s.seqIndex += 1
+			if s.seqIndex == 3 {
+				// Time to evaluate
+				yes := s.seq[0] >= 180 &&
+					s.seq[1] <= 11000 &&
+					s.seq[2] >= 40
 				return &analyzer.PropUpdate{
 					Type: analyzer.PropUpdateReplace,
 					M: analyzer.PropMap{
-						"up":   s.upCount,
-						"down": s.downCount,
-						"yes":  true,
+						"seq": s.seq,
+						"yes": yes,
 					},
 				}, true
 			}
-			s.upCount += len(data)
+			s.seq[s.seqIndex] += len(data)
+			s.rev = rev
 		}
 	}
-	// Give up when either direction is over the limit
-	return nil, s.upCount > trojanUpUB || s.downCount > trojanDownUB2
+
+	return nil, false
 }

 func (s *trojanStream) Close(limited bool) *analyzer.PropUpdate {
--- a/analyzer/udp/quic.go
+++ b/analyzer/udp/quic.go
@@ -36,41 +36,40 @@ type quicStream struct {
 }

 func (s *quicStream) Feed(rev bool, data []byte) (u *analyzer.PropUpdate, done bool) {
+	// minimal data size: protocol version (2 bytes) + random (32 bytes) +
+	//   + session ID (1 byte) + cipher suites (4 bytes) +
+	//   + compression methods (2 bytes) + no extensions
+	const minDataSize = 41
+
 	if rev {
 		// We don't support server direction for now
 		s.invalidCount++
 		return nil, s.invalidCount >= quicInvalidCountThreshold
 	}
+
 	pl, err := quic.ReadCryptoPayload(data)
-	if err != nil || len(pl) < 4 {
+	if err != nil || len(pl) < 4 { // FIXME: isn't length checked inside quic.ReadCryptoPayload? Also, what about error handling?
 		s.invalidCount++
 		return nil, s.invalidCount >= quicInvalidCountThreshold
 	}
-	// Should be a TLS client hello
-	if pl[0] != 0x01 {
-		// Not a client hello
+
+	if pl[0] != internal.TypeClientHello {
 		s.invalidCount++
 		return nil, s.invalidCount >= quicInvalidCountThreshold
 	}
+
 	chLen := int(pl[1])<<16 | int(pl[2])<<8 | int(pl[3])
-	if chLen < 41 {
-		// 2 (Protocol Version) +
-		// 32 (Random) +
-		// 1 (Session ID Length) +
-		// 2 (Cipher Suites Length) +_ws.col.protocol == "TLSv1.3"
-		// 2 (Cipher Suite) +
-		// 1 (Compression Methods Length) +
-		// 1 (Compression Method) +
-		// No extensions
-		// This should be the bare minimum for a client hello
+	if chLen < minDataSize {
 		s.invalidCount++
 		return nil, s.invalidCount >= quicInvalidCountThreshold
 	}
-	m := internal.ParseTLSClientHello(&utils.ByteBuffer{Buf: pl[4:]})
+
+	m := internal.ParseTLSClientHelloMsgData(&utils.ByteBuffer{Buf: pl[4:]})
 	if m == nil {
 		s.invalidCount++
 		return nil, s.invalidCount >= quicInvalidCountThreshold
 	}
+
 	return &analyzer.PropUpdate{
 		Type: analyzer.PropUpdateMerge,
 		M:    analyzer.PropMap{"req": m},
--- a/analyzer/udp/quic_test.go
+++ b/analyzer/udp/quic_test.go
@@ -0,0 +1,58 @@
+package udp
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/apernet/OpenGFW/analyzer"
+)
+
+func TestQuicStreamParsing_ClientHello(t *testing.T) {
+	// example packet taken from <https://quic.xargs.org/#client-initial-packet/annotated>
+	clientHello := make([]byte, 1200)
+	clientInitial := []byte{
+		0xcd, 0x00, 0x00, 0x00, 0x01, 0x08, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05,
+		0x06, 0x07, 0x05, 0x63, 0x5f, 0x63, 0x69, 0x64, 0x00, 0x41, 0x03, 0x98,
+		0x1c, 0x36, 0xa7, 0xed, 0x78, 0x71, 0x6b, 0xe9, 0x71, 0x1b, 0xa4, 0x98,
+		0xb7, 0xed, 0x86, 0x84, 0x43, 0xbb, 0x2e, 0x0c, 0x51, 0x4d, 0x4d, 0x84,
+		0x8e, 0xad, 0xcc, 0x7a, 0x00, 0xd2, 0x5c, 0xe9, 0xf9, 0xaf, 0xa4, 0x83,
+		0x97, 0x80, 0x88, 0xde, 0x83, 0x6b, 0xe6, 0x8c, 0x0b, 0x32, 0xa2, 0x45,
+		0x95, 0xd7, 0x81, 0x3e, 0xa5, 0x41, 0x4a, 0x91, 0x99, 0x32, 0x9a, 0x6d,
+		0x9f, 0x7f, 0x76, 0x0d, 0xd8, 0xbb, 0x24, 0x9b, 0xf3, 0xf5, 0x3d, 0x9a,
+		0x77, 0xfb, 0xb7, 0xb3, 0x95, 0xb8, 0xd6, 0x6d, 0x78, 0x79, 0xa5, 0x1f,
+		0xe5, 0x9e, 0xf9, 0x60, 0x1f, 0x79, 0x99, 0x8e, 0xb3, 0x56, 0x8e, 0x1f,
+		0xdc, 0x78, 0x9f, 0x64, 0x0a, 0xca, 0xb3, 0x85, 0x8a, 0x82, 0xef, 0x29,
+		0x30, 0xfa, 0x5c, 0xe1, 0x4b, 0x5b, 0x9e, 0xa0, 0xbd, 0xb2, 0x9f, 0x45,
+		0x72, 0xda, 0x85, 0xaa, 0x3d, 0xef, 0x39, 0xb7, 0xef, 0xaf, 0xff, 0xa0,
+		0x74, 0xb9, 0x26, 0x70, 0x70, 0xd5, 0x0b, 0x5d, 0x07, 0x84, 0x2e, 0x49,
+		0xbb, 0xa3, 0xbc, 0x78, 0x7f, 0xf2, 0x95, 0xd6, 0xae, 0x3b, 0x51, 0x43,
+		0x05, 0xf1, 0x02, 0xaf, 0xe5, 0xa0, 0x47, 0xb3, 0xfb, 0x4c, 0x99, 0xeb,
+		0x92, 0xa2, 0x74, 0xd2, 0x44, 0xd6, 0x04, 0x92, 0xc0, 0xe2, 0xe6, 0xe2,
+		0x12, 0xce, 0xf0, 0xf9, 0xe3, 0xf6, 0x2e, 0xfd, 0x09, 0x55, 0xe7, 0x1c,
+		0x76, 0x8a, 0xa6, 0xbb, 0x3c, 0xd8, 0x0b, 0xbb, 0x37, 0x55, 0xc8, 0xb7,
+		0xeb, 0xee, 0x32, 0x71, 0x2f, 0x40, 0xf2, 0x24, 0x51, 0x19, 0x48, 0x70,
+		0x21, 0xb4, 0xb8, 0x4e, 0x15, 0x65, 0xe3, 0xca, 0x31, 0x96, 0x7a, 0xc8,
+		0x60, 0x4d, 0x40, 0x32, 0x17, 0x0d, 0xec, 0x28, 0x0a, 0xee, 0xfa, 0x09,
+		0x5d, 0x08, 0xb3, 0xb7, 0x24, 0x1e, 0xf6, 0x64, 0x6a, 0x6c, 0x86, 0xe5,
+		0xc6, 0x2c, 0xe0, 0x8b, 0xe0, 0x99,
+	}
+	copy(clientHello, clientInitial)
+
+	want := analyzer.PropMap{
+		"alpn":               []string{"ping/1.0"},
+		"ciphers":            []uint16{4865, 4866, 4867},
+		"compression":        []uint8{0},
+		"random":             []uint8{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31},
+		"session":            []uint8{},
+		"sni":                "example.ulfheim.net",
+		"supported_versions": []uint16{772},
+		"version":            uint16(771),
+	}
+
+	s := quicStream{}
+	u, _ := s.Feed(false, clientHello)
+	got := u.M.Get("req")
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("%d B parsed = %v, want %v", len(clientHello), got, want)
+	}
+}
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"os"
 	"os/signal"
-	"strconv"
 	"strings"
 	"syscall"

@@ -168,8 +167,11 @@ type cliConfig struct {
 }

 type cliConfigIO struct {
-	QueueSize uint32 `mapstructure:"queueSize"`
-	Local     bool   `mapstructure:"local"`
+	QueueSize   uint32 `mapstructure:"queueSize"`
+	ReadBuffer  int    `mapstructure:"rcvBuf"`
+	WriteBuffer int    `mapstructure:"sndBuf"`
+	Local       bool   `mapstructure:"local"`
+	RST         bool   `mapstructure:"rst"`
 }

 type cliConfigWorkers struct {
@@ -192,8 +194,11 @@ func (c *cliConfig) fillLogger(config *engine.Config) error {

 func (c *cliConfig) fillIO(config *engine.Config) error {
 	nfio, err := io.NewNFQueuePacketIO(io.NFQueuePacketIOConfig{
-		QueueSize: c.IO.QueueSize,
-		Local:     c.IO.Local,
+		QueueSize:   c.IO.QueueSize,
+		ReadBuffer:  c.IO.ReadBuffer,
+		WriteBuffer: c.IO.WriteBuffer,
+		Local:       c.IO.Local,
+		RST:         c.IO.RST,
 	})
 	if err != nil {
 		return configError{Field: "io", Err: err}
@@ -274,15 +279,15 @@ func runMain(cmd *cobra.Command, args []string) {
 	ctx, cancelFunc := context.WithCancel(context.Background())
 	go func() {
 		// Graceful shutdown
-		shutdownChan := make(chan os.Signal)
-		signal.Notify(shutdownChan, os.Interrupt, os.Kill)
+		shutdownChan := make(chan os.Signal, 1)
+		signal.Notify(shutdownChan, os.Interrupt, syscall.SIGTERM)
 		<-shutdownChan
 		logger.Info("shutting down gracefully...")
 		cancelFunc()
 	}()
 	go func() {
 		// Rule reload
-		reloadChan := make(chan os.Signal)
+		reloadChan := make(chan os.Signal, 1)
 		signal.Notify(reloadChan, syscall.SIGHUP)
 		for {
 			<-reloadChan
@@ -427,11 +432,3 @@ func envOrDefaultString(key, def string) string {
 	}
 	return def
 }
-
-func envOrDefaultBool(key string, def bool) bool {
-	if v := os.Getenv(key); v != "" {
-		b, _ := strconv.ParseBool(v)
-		return b
-	}
-	return def
-}
--- a/docs/Analyzers.md
+++ b/docs/Analyzers.md
@@ -246,13 +246,10 @@ Example for blocking QUIC connections to `quic.rocks`:

 ## Trojan (proxy protocol)

-Check https://github.com/XTLS/Trojan-killer for more information.
-
 ```json
 {
  "trojan": {
-    "down": 4712,
-    "up": 671,
+    "seq": [680, 4514, 293],
    "yes": true
  }
 }
--- a/go.mod
+++ b/go.mod
@@ -13,15 +13,14 @@ require (
 	github.com/quic-go/quic-go v0.41.0
 	github.com/spf13/cobra v1.8.0
 	github.com/spf13/viper v1.18.2
-	github.com/stretchr/testify v1.8.4
 	go.uber.org/zap v1.26.0
 	golang.org/x/crypto v0.19.0
+	golang.org/x/sys v0.17.0
 	google.golang.org/protobuf v1.31.0
 	gopkg.in/yaml.v3 v3.0.1
 )

 require (
-	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/fsnotify/fsnotify v1.7.0 // indirect
 	github.com/google/go-cmp v0.5.9 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
@@ -31,7 +30,6 @@ require (
 	github.com/mdlayher/socket v0.1.1 // indirect
 	github.com/mitchellh/mapstructure v1.5.0 // indirect
 	github.com/pelletier/go-toml/v2 v2.1.0 // indirect
-	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/sagikazarmark/locafero v0.4.0 // indirect
 	github.com/sagikazarmark/slog-shim v0.1.0 // indirect
 	github.com/sourcegraph/conc v0.3.0 // indirect
@@ -43,7 +41,6 @@ require (
 	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect
 	golang.org/x/net v0.19.0 // indirect
 	golang.org/x/sync v0.5.0 // indirect
-	golang.org/x/sys v0.17.0 // indirect
 	golang.org/x/text v0.14.0 // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect
 )
--- a/io/nfqueue.go
+++ b/io/nfqueue.go
@@ -12,6 +12,7 @@ import (
 	"github.com/coreos/go-iptables/iptables"
 	"github.com/florianl/go-nfqueue"
 	"github.com/mdlayher/netlink"
+	"golang.org/x/sys/unix"
 )

 const (
@@ -26,59 +27,60 @@ const (
 	nftTable  = "opengfw"
 )

-var nftRulesForward = fmt.Sprintf(`
-define ACCEPT_CTMARK=%d
-define DROP_CTMARK=%d
-define QUEUE_NUM=%d
-
-table %s %s {
-  chain FORWARD {
-    type filter hook forward priority filter; policy accept;
-
-    ct mark $ACCEPT_CTMARK counter accept
-    ct mark $DROP_CTMARK counter drop
-    counter queue num $QUEUE_NUM bypass
-  }
-}
-`, nfqueueConnMarkAccept, nfqueueConnMarkDrop, nfqueueNum, nftFamily, nftTable)
-
-var nftRulesLocal = fmt.Sprintf(`
-define ACCEPT_CTMARK=%d
-define DROP_CTMARK=%d
-define QUEUE_NUM=%d
-
-table %s %s {
-  chain INPUT {
-    type filter hook input priority filter; policy accept;
-
-    ct mark $ACCEPT_CTMARK counter accept
-    ct mark $DROP_CTMARK counter drop
-    counter queue num $QUEUE_NUM bypass
-  }
-  chain OUTPUT {
-    type filter hook output priority filter; policy accept;
-
-    ct mark $ACCEPT_CTMARK counter accept
-    ct mark $DROP_CTMARK counter drop
-    counter queue num $QUEUE_NUM bypass
-  }
-}
-`, nfqueueConnMarkAccept, nfqueueConnMarkDrop, nfqueueNum, nftFamily, nftTable)
-
-var iptRulesForward = []iptRule{
-	{"filter", "FORWARD", []string{"-m", "connmark", "--mark", strconv.Itoa(nfqueueConnMarkAccept), "-j", "ACCEPT"}},
-	{"filter", "FORWARD", []string{"-m", "connmark", "--mark", strconv.Itoa(nfqueueConnMarkDrop), "-j", "DROP"}},
-	{"filter", "FORWARD", []string{"-j", "NFQUEUE", "--queue-num", strconv.Itoa(nfqueueNum), "--queue-bypass"}},
+func generateNftRules(local, rst bool) (*nftTableSpec, error) {
+	if local && rst {
+		return nil, errors.New("tcp rst is not supported in local mode")
+	}
+	table := &nftTableSpec{
+		Family: nftFamily,
+		Table:  nftTable,
+	}
+	table.Defines = append(table.Defines, fmt.Sprintf("define ACCEPT_CTMARK=%d", nfqueueConnMarkAccept))
+	table.Defines = append(table.Defines, fmt.Sprintf("define DROP_CTMARK=%d", nfqueueConnMarkDrop))
+	table.Defines = append(table.Defines, fmt.Sprintf("define QUEUE_NUM=%d", nfqueueNum))
+	if local {
+		table.Chains = []nftChainSpec{
+			{Chain: "INPUT", Header: "type filter hook input priority filter; policy accept;"},
+			{Chain: "OUTPUT", Header: "type filter hook output priority filter; policy accept;"},
+		}
+	} else {
+		table.Chains = []nftChainSpec{
+			{Chain: "FORWARD", Header: "type filter hook forward priority filter; policy accept;"},
+		}
+	}
+	for i := range table.Chains {
+		c := &table.Chains[i]
+		c.Rules = append(c.Rules, "ct mark $ACCEPT_CTMARK counter accept")
+		if rst {
+			c.Rules = append(c.Rules, "ip protocol tcp ct mark $DROP_CTMARK counter reject with tcp reset")
+		}
+		c.Rules = append(c.Rules, "ct mark $DROP_CTMARK counter drop")
+		c.Rules = append(c.Rules, "counter queue num $QUEUE_NUM bypass")
+	}
+	return table, nil
 }

-var iptRulesLocal = []iptRule{
-	{"filter", "INPUT", []string{"-m", "connmark", "--mark", strconv.Itoa(nfqueueConnMarkAccept), "-j", "ACCEPT"}},
-	{"filter", "INPUT", []string{"-m", "connmark", "--mark", strconv.Itoa(nfqueueConnMarkDrop), "-j", "DROP"}},
-	{"filter", "INPUT", []string{"-j", "NFQUEUE", "--queue-num", strconv.Itoa(nfqueueNum), "--queue-bypass"}},
+func generateIptRules(local, rst bool) ([]iptRule, error) {
+	if local && rst {
+		return nil, errors.New("tcp rst is not supported in local mode")
+	}
+	var chains []string
+	if local {
+		chains = []string{"INPUT", "OUTPUT"}
+	} else {
+		chains = []string{"FORWARD"}
+	}
+	rules := make([]iptRule, 0, 4*len(chains))
+	for _, chain := range chains {
+		rules = append(rules, iptRule{"filter", chain, []string{"-m", "connmark", "--mark", strconv.Itoa(nfqueueConnMarkAccept), "-j", "ACCEPT"}})
+		if rst {
+			rules = append(rules, iptRule{"filter", chain, []string{"-p", "tcp", "-m", "connmark", "--mark", strconv.Itoa(nfqueueConnMarkDrop), "-j", "REJECT", "--reject-with", "tcp-reset"}})
+		}
+		rules = append(rules, iptRule{"filter", chain, []string{"-m", "connmark", "--mark", strconv.Itoa(nfqueueConnMarkDrop), "-j", "DROP"}})
+		rules = append(rules, iptRule{"filter", chain, []string{"-j", "NFQUEUE", "--queue-num", strconv.Itoa(nfqueueNum), "--queue-bypass"}})
+	}

-	{"filter", "OUTPUT", []string{"-m", "connmark", "--mark", strconv.Itoa(nfqueueConnMarkAccept), "-j", "ACCEPT"}},
-	{"filter", "OUTPUT", []string{"-m", "connmark", "--mark", strconv.Itoa(nfqueueConnMarkDrop), "-j", "DROP"}},
-	{"filter", "OUTPUT", []string{"-j", "NFQUEUE", "--queue-num", strconv.Itoa(nfqueueNum), "--queue-bypass"}},
+	return rules, nil
 }

 var _ PacketIO = (*nfqueuePacketIO)(nil)
@@ -88,6 +90,7 @@ var errNotNFQueuePacket = errors.New("not an NFQueue packet")
 type nfqueuePacketIO struct {
 	n     *nfqueue.Nfqueue
 	local bool
+	rst   bool
 	rSet  bool // whether the nftables/iptables rules have been set

 	// iptables not nil = use iptables instead of nftables
@@ -96,8 +99,11 @@ type nfqueuePacketIO struct {
 }

 type NFQueuePacketIOConfig struct {
-	QueueSize uint32
-	Local     bool
+	QueueSize   uint32
+	ReadBuffer  int
+	WriteBuffer int
+	Local       bool
+	RST         bool
 }

 func NewNFQueuePacketIO(config NFQueuePacketIOConfig) (PacketIO, error) {
@@ -127,9 +133,24 @@ func NewNFQueuePacketIO(config NFQueuePacketIOConfig) (PacketIO, error) {
 	if err != nil {
 		return nil, err
 	}
+	if config.ReadBuffer > 0 {
+		err = n.Con.SetReadBuffer(config.ReadBuffer)
+		if err != nil {
+			_ = n.Close()
+			return nil, err
+		}
+	}
+	if config.WriteBuffer > 0 {
+		err = n.Con.SetWriteBuffer(config.WriteBuffer)
+		if err != nil {
+			_ = n.Close()
+			return nil, err
+		}
+	}
 	return &nfqueuePacketIO{
 		n:     n,
 		local: config.Local,
+		rst:   config.RST,
 		ipt4:  ipt4,
 		ipt6:  ipt6,
 	}, nil
@@ -138,9 +159,10 @@ func NewNFQueuePacketIO(config NFQueuePacketIOConfig) (PacketIO, error) {
 func (n *nfqueuePacketIO) Register(ctx context.Context, cb PacketCallback) error {
 	err := n.n.RegisterWithErrorFunc(ctx,
 		func(a nfqueue.Attribute) int {
-			if a.PacketID == nil || a.Ct == nil || a.Payload == nil || len(*a.Payload) < 20 {
-				// Invalid packet, ignore
-				// 20 is the minimum possible size of an IP packet
+			if ok, verdict := n.packetAttributeSanityCheck(a); !ok {
+				if a.PacketID != nil {
+					_ = n.n.SetVerdict(*a.PacketID, verdict)
+				}
 				return 0
 			}
 			p := &nfqueuePacket{
@@ -151,6 +173,12 @@ func (n *nfqueuePacketIO) Register(ctx context.Context, cb PacketCallback) error
 			return okBoolToInt(cb(p, nil))
 		},
 		func(e error) int {
+			if opErr := (*netlink.OpError)(nil); errors.As(e, &opErr) {
+				if errors.Is(opErr.Err, unix.ENOBUFS) {
+					// Kernel buffer temporarily full, ignore
+					return 0
+				}
+			}
 			return okBoolToInt(cb(nil, e))
 		})
 	if err != nil {
@@ -158,9 +186,9 @@ func (n *nfqueuePacketIO) Register(ctx context.Context, cb PacketCallback) error
 	}
 	if !n.rSet {
 		if n.ipt4 != nil {
-			err = n.setupIpt(n.local, false)
+			err = n.setupIpt(n.local, n.rst, false)
 		} else {
-			err = n.setupNft(n.local, false)
+			err = n.setupNft(n.local, n.rst, false)
 		}
 		if err != nil {
 			return err
@@ -170,6 +198,25 @@ func (n *nfqueuePacketIO) Register(ctx context.Context, cb PacketCallback) error
 	return nil
 }

+func (n *nfqueuePacketIO) packetAttributeSanityCheck(a nfqueue.Attribute) (ok bool, verdict int) {
+	if a.PacketID == nil {
+		// Re-inject to NFQUEUE is actually not possible in this condition
+		return false, -1
+	}
+	if a.Payload == nil || len(*a.Payload) < 20 {
+		// 20 is the minimum possible size of an IP packet
+		return false, nfqueue.NfDrop
+	}
+	if a.Ct == nil {
+		// Multicast packets may not have a conntrack, but only appear in local mode
+		if n.local {
+			return false, nfqueue.NfAccept
+		}
+		return false, nfqueue.NfDrop
+	}
+	return true, -1
+}
+
 func (n *nfqueuePacketIO) SetVerdict(p Packet, v Verdict, newPacket []byte) error {
 	nP, ok := p.(*nfqueuePacket)
 	if !ok {
@@ -195,29 +242,27 @@ func (n *nfqueuePacketIO) SetVerdict(p Packet, v Verdict, newPacket []byte) erro
 func (n *nfqueuePacketIO) Close() error {
 	if n.rSet {
 		if n.ipt4 != nil {
-			_ = n.setupIpt(n.local, true)
+			_ = n.setupIpt(n.local, n.rst, true)
 		} else {
-			_ = n.setupNft(n.local, true)
+			_ = n.setupNft(n.local, n.rst, true)
 		}
 		n.rSet = false
 	}
 	return n.n.Close()
 }

-func (n *nfqueuePacketIO) setupNft(local, remove bool) error {
-	var rules string
-	if local {
-		rules = nftRulesLocal
-	} else {
-		rules = nftRulesForward
+func (n *nfqueuePacketIO) setupNft(local, rst, remove bool) error {
+	rules, err := generateNftRules(local, rst)
+	if err != nil {
+		return err
 	}
-	var err error
+	rulesText := rules.String()
 	if remove {
 		err = nftDelete(nftFamily, nftTable)
 	} else {
 		// Delete first to make sure no leftover rules
 		_ = nftDelete(nftFamily, nftTable)
-		err = nftAdd(rules)
+		err = nftAdd(rulesText)
 	}
 	if err != nil {
 		return err
@@ -225,14 +270,11 @@ func (n *nfqueuePacketIO) setupNft(local, remove bool) error {
 	return nil
 }

-func (n *nfqueuePacketIO) setupIpt(local, remove bool) error {
-	var rules []iptRule
-	if local {
-		rules = iptRulesLocal
-	} else {
-		rules = iptRulesForward
+func (n *nfqueuePacketIO) setupIpt(local, rst, remove bool) error {
+	rules, err := generateIptRules(local, rst)
+	if err != nil {
+		return err
 	}
-	var err error
 	if remove {
 		err = iptsBatchDeleteIfExists([]*iptables.IPTables{n.ipt4, n.ipt6}, rules)
 	} else {
@@ -287,6 +329,42 @@ func nftDelete(family, table string) error {
 	return cmd.Run()
 }

+type nftTableSpec struct {
+	Defines       []string
+	Family, Table string
+	Chains        []nftChainSpec
+}
+
+func (t *nftTableSpec) String() string {
+	chains := make([]string, 0, len(t.Chains))
+	for _, c := range t.Chains {
+		chains = append(chains, c.String())
+	}
+
+	return fmt.Sprintf(`
+%s
+
+table %s %s {
+%s
+}
+`, strings.Join(t.Defines, "\n"), t.Family, t.Table, strings.Join(chains, ""))
+}
+
+type nftChainSpec struct {
+	Chain  string
+	Header string
+	Rules  []string
+}
+
+func (c *nftChainSpec) String() string {
+	return fmt.Sprintf(`
+  chain %s {
+    %s
+    %s
+  }
+`, c.Chain, c.Header, strings.Join(c.Rules, "\n\x20\x20\x20\x20"))
+}
+
 type iptRule struct {
 	Table, Chain string
 	RuleSpec     []string
--- a/ruleset/builtins/geo/geo_loader.go
+++ b/ruleset/builtins/geo/geo_loader.go
@@ -49,7 +49,7 @@ func (l *V2GeoLoader) shouldDownload(filename string) bool {
 	if os.IsNotExist(err) {
 		return true
 	}
-	dt := time.Now().Sub(info.ModTime())
+	dt := time.Since(info.ModTime())
 	if l.UpdateInterval == 0 {
 		return dt > geoDefaultUpdateInterval
 	} else {
--- a/ruleset/builtins/geo/v2geo/load_test.go
+++ b/ruleset/builtins/geo/v2geo/load_test.go
@@ -1,54 +0,0 @@
-package v2geo
-
-import (
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-)
-
-func TestLoadGeoIP(t *testing.T) {
-	m, err := LoadGeoIP("geoip.dat")
-	assert.NoError(t, err)
-
-	// Exact checks since we know the data.
-	assert.Len(t, m, 252)
-	assert.Equal(t, m["cn"].CountryCode, "CN")
-	assert.Len(t, m["cn"].Cidr, 10407)
-	assert.Equal(t, m["us"].CountryCode, "US")
-	assert.Len(t, m["us"].Cidr, 193171)
-	assert.Equal(t, m["private"].CountryCode, "PRIVATE")
-	assert.Len(t, m["private"].Cidr, 18)
-	assert.Contains(t, m["private"].Cidr, &CIDR{
-		Ip:     []byte("\xc0\xa8\x00\x00"),
-		Prefix: 16,
-	})
-}
-
-func TestLoadGeoSite(t *testing.T) {
-	m, err := LoadGeoSite("geosite.dat")
-	assert.NoError(t, err)
-
-	// Exact checks since we know the data.
-	assert.Len(t, m, 1204)
-	assert.Equal(t, m["netflix"].CountryCode, "NETFLIX")
-	assert.Len(t, m["netflix"].Domain, 25)
-	assert.Contains(t, m["netflix"].Domain, &Domain{
-		Type:  Domain_Full,
-		Value: "netflix.com.edgesuite.net",
-	})
-	assert.Contains(t, m["netflix"].Domain, &Domain{
-		Type:  Domain_RootDomain,
-		Value: "fast.com",
-	})
-	assert.Len(t, m["google"].Domain, 1066)
-	assert.Contains(t, m["google"].Domain, &Domain{
-		Type:  Domain_RootDomain,
-		Value: "ggpht.cn",
-		Attribute: []*Domain_Attribute{
-			{
-				Key:        "cn",
-				TypedValue: &Domain_Attribute_BoolValue{BoolValue: true},
-			},
-		},
-	})
-}
Author	SHA1	Message	Date
Toby	bf2988116a	Merge pull request #109 from apernet/wip-io-rst feat: io tcp reset support (forward only)	2024-03-21 18:43:43 -07:00
Haruue	ef1416274d	refactor(io): nft/ipt generator func	2024-03-22 02:04:25 +08:00
Toby	57c818038c	feat: io tcp reset support (forward only)	2024-03-20 19:01:26 -07:00
Toby	6ad7714c9a	Merge pull request #108 from apernet/fix-trojan-doc docs: remove trojan-killer ref	2024-03-20 18:41:45 -07:00
Toby	ff9c4ccf79	docs: remove trojan-killer ref	2024-03-20 18:40:49 -07:00
Toby	e1d9406fdb	Merge pull request #107 from apernet/fix-trojan fix: trojan analyzer heuristics	2024-03-20 18:39:05 -07:00
Toby	b8e5079b8a	fix: trojan analyzer heuristics	2024-03-20 18:37:43 -07:00
Toby	f3b72895ad	Merge pull request #106 from apernet/wip-new-trojan feat: new heuristics for trojan analyzer	2024-03-20 18:11:09 -07:00
Toby	0732dfa7a5	docs: no longer use trojan-killer	2024-03-20 18:10:22 -07:00
Toby	9d96acd8db	feat: new heuristics for trojan analyzer	2024-03-20 18:07:26 -07:00
Toby	d1775184ce	Merge pull request #102 from macie/badge_fix docs: Fix status badge URL	2024-03-14 00:37:37 -07:00
macie	05d56616fc	ci: Add readable name for workflow It is visible on Workflows list inside GH Actions tab.	2024-03-14 08:14:30 +01:00
macie	ede70e1a87	docs: Fix badge URL	2024-03-14 08:06:27 +01:00
Toby	920783bd65	Merge pull request #98 from macie/ci CI/CD: New workflow for testing and static analysis	2024-03-13 19:29:36 -07:00
macie	3a45461c19	test: Remove broken integration test This tests fails when there are no specific binary files, but there is no method to get the files during test. Marking the tests as a skipped will gives us a false sense of security. So it's better to remove it at all.	2024-03-12 12:15:10 +01:00
macie	3022bde81b	fix: Linter errors Fixed: - "ineffective break statement. Did you mean to break out of the outer loop?" (SA4011) - "channels used with os/signal.Notify should be buffered" (SA1017) - "os.Kill cannot be trapped (did you mean syscall.SIGTERM?)" (SA1016) - "func envOrDefaultBool is unused" (U1000) - "should use time.Since instead of time.Now().Sub" (S1012)	2024-03-12 12:14:58 +01:00
macie	d98136bac7	ci: Add quality check Runs tests and linters after each commit.	2024-03-11 22:19:26 +01:00
macie	c0e2483f6c	test: Add basic tests for packet parsing Tests performed on real-like packets secure expected behavior.	2024-03-11 21:25:34 +01:00
macie	3bd02ed46e	refactor: Improve parsing docs Reveal intentions by: - extracting magic numbers into constants - changing function names with >1 responsibilities - documenting non-obvious behaviors.	2024-03-11 20:35:01 +01:00
Toby	4257788f33	Merge pull request #92 from apernet/wip-doc-openwrt-ipt docs: instruction for OpenWrt 22.02 or earlier	2024-03-09 09:23:53 -08:00
Haruue	e77c2fabea	docs: instruction for OpenWrt 22.02 or earlier	2024-03-09 21:42:49 +08:00
Toby	1dce82745d	Merge pull request #85 from apernet/wip-buf feat: netlink rcv/snd buffer config options	2024-02-29 11:23:08 -08:00
Toby	50cc94889f	feat: netlink rcv/snd buffer config options	2024-02-28 17:45:24 -08:00
Toby	5d2d874089	Merge pull request #82 from apernet/update-fet feat: update FET analyzer to better reflect what's described in the paper	2024-02-26 15:28:33 -08:00
Toby	797dce3dc2	feat: update FET analyzer to better reflect what's described in the paper	2024-02-26 15:27:35 -08:00
Toby	420286a46c	Merge pull request #81 from apernet/update-gfwreport chore: update gfw report links	2024-02-26 15:17:33 -08:00
Toby	531a7b0ceb	chore: update gfw report links	2024-02-26 15:17:07 -08:00
Toby	20e0637756	Merge pull request #79 from apernet/update-ci fix: release workflow	2024-02-26 10:50:44 -08:00
Toby	74dcc92fc6	fix: release workflow	2024-02-26 10:49:19 -08:00
Toby	b780ff65a4	Merge pull request #76 from apernet/fix-enobufs fix: engine exit with "netlink receive: recvmsg: no buffer space available" when too many packets hit NFQUEUE	2024-02-26 10:40:08 -08:00
Haruue	8bd34d7798	chore: go mod tidy	2024-02-26 16:48:39 +08:00
Haruue	bed34f94be	fix: engine exit when too many packets hit NFQUEUE	2024-02-26 16:46:50 +08:00
Toby	bc2e21e35d	Merge pull request #75 from apernet/fix-missing-verdict fix: verdict is missing for multicast packets	2024-02-26 00:12:42 -08:00
Haruue	a0b994ce22	fix: verdict is missing for multicast packets	2024-02-26 15:45:07 +08:00