documentation: Bump version

Reference: https://gitlab.com/go-extension/tls

.github/setup_go_for_windows7.sh

@@ -1,25 +1,27 @@
 #!/usr/bin/env bash
 
-VERSION="1.23.6"
+VERSION="1.25.1"
 
 mkdir -p $HOME/go
 cd $HOME/go
 wget "https://dl.google.com/go/go${VERSION}.linux-amd64.tar.gz"
 tar -xzf "go${VERSION}.linux-amd64.tar.gz"
-mv go go_legacy
-cd go_legacy
+mv go go_win7
+cd go_win7
 
 # modify from https://github.com/restic/restic/issues/4636#issuecomment-1896455557
-# this patch file only works on golang1.23.x
-# that means after golang1.24 release it must be changed
-# see: https://github.com/MetaCubeX/go/commits/release-branch.go1.23/
+# this patch file only works on golang1.25.x
+# that means after golang1.26 release it must be changed
+# see: https://github.com/MetaCubeX/go/commits/release-branch.go1.25/
 # revert:
 # 693def151adff1af707d82d28f55dba81ceb08e1: "crypto/rand,runtime: switch RtlGenRandom for ProcessPrng"
 # 7c1157f9544922e96945196b47b95664b1e39108: "net: remove sysSocket fallback for Windows 7"
 # 48042aa09c2f878c4faa576948b07fe625c4707a: "syscall: remove Windows 7 console handle workaround"
 # a17d959debdb04cd550016a3501dd09d50cd62e7: "runtime: always use LoadLibraryEx to load system libraries"
 
-curl https://github.com/MetaCubeX/go/commit/9ac42137ef6730e8b7daca016ece831297a1d75b.diff | patch --verbose -p 1
-curl https://github.com/MetaCubeX/go/commit/21290de8a4c91408de7c2b5b68757b1e90af49dd.diff | patch --verbose -p 1
-curl https://github.com/MetaCubeX/go/commit/6a31d3fa8e47ddabc10bd97bff10d9a85f4cfb76.diff | patch --verbose -p 1
-curl https://github.com/MetaCubeX/go/commit/69e2eed6dd0f6d815ebf15797761c13f31213dd6.diff | patch --verbose -p 1
+alias curl='curl -H "Authorization: Bearer ${{ secrets.GITHUB_TOKEN }}"'
+
+curl https://github.com/MetaCubeX/go/commit/8cb5472d94c34b88733a81091bd328e70ee565a4.diff | patch --verbose -p 1
+curl https://github.com/MetaCubeX/go/commit/6788c4c6f9fafb56729bad6b660f7ee2272d699f.diff | patch --verbose -p 1
+curl https://github.com/MetaCubeX/go/commit/a5b2168bb836ed9d6601c626f95e56c07923f906.diff | patch --verbose -p 1
+curl https://github.com/MetaCubeX/go/commit/f56f1e23507e646c85243a71bde7b9629b2f970c.diff | patch --verbose -p 1

.github/workflows/build.yml

@@ -40,13 +40,13 @@ jobs:
       version: ${{ steps.outputs.outputs.version }}
     steps:
       - name: Checkout
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           fetch-depth: 0
       - name: Setup Go
         uses: actions/setup-go@v5
         with:
-          go-version: ^1.24
+          go-version: ^1.25.1
       - name: Check input version
         if: github.event_name == 'workflow_dispatch'
         run: |-
@@ -88,13 +88,14 @@ jobs:
           - { os: linux, arch: loong64, debian: loongarch64, rpm: loongarch64, openwrt: "loongarch64_generic" }
 
           - { os: windows, arch: amd64 }
-          - { os: windows, arch: amd64, legacy_go: true }
+          - { os: windows, arch: amd64, legacy_win7: true, legacy_name: "windows-7" }
           - { os: windows, arch: "386" }
-          - { os: windows, arch: "386", legacy_go: true }
+          - { os: windows, arch: "386", legacy_win7: true, legacy_name: "windows-7" }
           - { os: windows, arch: arm64 }
 
           - { os: darwin, arch: amd64 }
           - { os: darwin, arch: arm64 }
+          - { os: darwin, arch: amd64, legacy_go124: true, legacy_name: "macos-11" }
 
           - { os: android, arch: arm64, ndk: "aarch64-linux-android21" }
           - { os: android, arch: arm, ndk: "armv7a-linux-androideabi21" }
@@ -102,31 +103,36 @@ jobs:
           - { os: android, arch: "386", ndk: "i686-linux-android21" }
     steps:
       - name: Checkout
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           fetch-depth: 0
       - name: Setup Go
-        if: ${{ ! matrix.legacy_go }}
+        if: ${{ ! (matrix.legacy_go123 || matrix.legacy_go124) }}
         uses: actions/setup-go@v5
         with:
-          go-version: ^1.24
-      - name: Cache Legacy Go
-        if: matrix.require_legacy_go
-        id: cache-legacy-go
+          go-version: ^1.25.1
+      - name: Setup Go 1.24
+        if: matrix.legacy_go124
+        uses: actions/setup-go@v5
+        with:
+          go-version: ~1.24.6
+      - name: Cache Go for Windows 7
+        if: matrix.legacy_win7
+        id: cache-go-for-windows7
         uses: actions/cache@v4
         with:
           path: |
-            ~/go/go_legacy
-          key: go_legacy_1236
-      - name: Setup Legacy Go
-        if: matrix.legacy_go && steps.cache-legacy-go.outputs.cache-hit != 'true'
+            ~/go/go_win7
+          key: go_win7_1251
+      - name: Setup Go for Windows 7
+        if: matrix.legacy_win7 && steps.cache-go-for-windows7.outputs.cache-hit != 'true'
         run: |-
-          .github/setup_legacy_go.sh
-      - name: Setup Legacy Go 2
-        if: matrix.legacy_go
+          .github/setup_go_for_windows7.sh
+      - name: Setup Go for Windows 7
+        if: matrix.legacy_win7
         run: |-
-          echo "PATH=$HOME/go/go_legacy/bin:$PATH" >> $GITHUB_ENV
-          echo "GOROOT=$HOME/go/go_legacy" >> $GITHUB_ENV
+          echo "PATH=$HOME/go/go_win7/bin:$PATH" >> $GITHUB_ENV
+          echo "GOROOT=$HOME/go/go_win7" >> $GITHUB_ENV
       - name: Setup Android NDK
         if: matrix.os == 'android'
         uses: nttld/setup-ndk@v1
@@ -148,7 +154,7 @@ jobs:
           set -xeuo pipefail
           mkdir -p dist
           go build -v -trimpath -o dist/sing-box -tags "${BUILD_TAGS}" \
-          -ldflags '-s -buildid= -X github.com/sagernet/sing-box/constant.Version=${{ needs.calculate_version.outputs.version }}' \
+          -ldflags '-s -buildid= -X github.com/sagernet/sing-box/constant.Version=${{ needs.calculate_version.outputs.version }} -checklinkname=0' \
           ./cmd/sing-box
         env:
           CGO_ENABLED: "0"
@@ -168,7 +174,7 @@ jobs:
           export CXX="${CC}++"
           mkdir -p dist
           GOOS=$BUILD_GOOS GOARCH=$BUILD_GOARCH build go build -v -trimpath -o dist/sing-box -tags "${BUILD_TAGS}" \
-          -ldflags '-s -buildid= -X github.com/sagernet/sing-box/constant.Version=${{ needs.calculate_version.outputs.version }}' \
+          -ldflags '-s -buildid= -X github.com/sagernet/sing-box/constant.Version=${{ needs.calculate_version.outputs.version }} -checklinkname=0' \
           ./cmd/sing-box
         env:
           CGO_ENABLED: "1"
@@ -184,8 +190,8 @@ jobs:
             DIR_NAME="${DIR_NAME}-${{ matrix.go386 }}"
           elif [[ -n "${{ matrix.gomips }}" && "${{ matrix.gomips }}" != 'hardfloat' ]]; then
             DIR_NAME="${DIR_NAME}-${{ matrix.gomips }}"
-          elif [[ "${{ matrix.legacy_go }}" == 'true' ]]; then
-            DIR_NAME="${DIR_NAME}-legacy"
+          elif [[ -n "${{ matrix.legacy_name }}" ]]; then
+            DIR_NAME="${DIR_NAME}-legacy-${{ matrix.legacy_name }}"
           fi
           echo "DIR_NAME=${DIR_NAME}" >> "${GITHUB_ENV}"
           PKG_VERSION="${{ needs.calculate_version.outputs.version }}"
@@ -277,7 +283,7 @@ jobs:
       - name: Upload artifact
         uses: actions/upload-artifact@v4
         with:
-          name: binary-${{ matrix.os }}_${{ matrix.arch }}${{ matrix.goarm && format('v{0}', matrix.goarm) }}${{ matrix.go386 && format('_{0}', matrix.go386) }}${{ matrix.gomips && format('_{0}', matrix.gomips) }}${{ matrix.legacy_go && '-legacy' || '' }}
+          name: binary-${{ matrix.os }}_${{ matrix.arch }}${{ matrix.goarm && format('v{0}', matrix.goarm) }}${{ matrix.go386 && format('_{0}', matrix.go386) }}${{ matrix.gomips && format('_{0}', matrix.gomips) }}${{ matrix.legacy_name && format('-legacy-{0}', matrix.legacy_name) }}
           path: "dist"
   build_android:
     name: Build Android
@@ -287,14 +293,14 @@ jobs:
       - calculate_version
     steps:
       - name: Checkout
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           fetch-depth: 0
           submodules: 'recursive'
       - name: Setup Go
         uses: actions/setup-go@v5
         with:
-          go-version: ^1.24
+          go-version: ^1.25.1
       - name: Setup Android NDK
         id: setup-ndk
         uses: nttld/setup-ndk@v1
@@ -367,14 +373,14 @@ jobs:
       - calculate_version
     steps:
       - name: Checkout
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           fetch-depth: 0
           submodules: 'recursive'
       - name: Setup Go
         uses: actions/setup-go@v5
         with:
-          go-version: ^1.24
+          go-version: ^1.25.1
       - name: Setup Android NDK
         id: setup-ndk
         uses: nttld/setup-ndk@v1
@@ -426,7 +432,8 @@ jobs:
           SERVICE_ACCOUNT_CREDENTIALS: ${{ secrets.SERVICE_ACCOUNT_CREDENTIALS }}
   build_apple:
     name: Build Apple clients
-    runs-on: macos-15
+    runs-on: macos-26
+    if: false
     needs:
       - calculate_version
     strategy:
@@ -464,7 +471,7 @@ jobs:
     steps:
       - name: Checkout
         if: matrix.if
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           fetch-depth: 0
           submodules: 'recursive'
@@ -472,15 +479,7 @@ jobs:
         if: matrix.if
         uses: actions/setup-go@v5
         with:
-          go-version: ^1.24
-      - name: Setup Xcode stable
-        if: matrix.if && github.ref == 'refs/heads/main-next'
-        run: |-
-          sudo xcode-select -s /Applications/Xcode_16.4.app
-      - name: Setup Xcode beta
-        if: matrix.if && github.ref == 'refs/heads/dev-next'
-        run: |-
-          sudo xcode-select -s /Applications/Xcode_16.4.app
+          go-version: ^1.25.1
       - name: Set tag
         if: matrix.if
         run: |-
@@ -624,7 +623,7 @@ jobs:
       - build_apple
     steps:
       - name: Checkout
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           fetch-depth: 0
       - name: Cache ghr
@@ -647,7 +646,7 @@ jobs:
           git tag v${{ needs.calculate_version.outputs.version }} -f
           echo "VERSION=${{ needs.calculate_version.outputs.version }}" >> "$GITHUB_ENV"
       - name: Download builds
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v5
         with:
           path: dist
           merge-multiple: true

.github/workflows/docker.yml

@@ -39,7 +39,7 @@ jobs:
           echo "ref=$ref"
           echo "ref=$ref" >> $GITHUB_OUTPUT
       - name: Checkout
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           ref: ${{ steps.ref.outputs.ref }}
           fetch-depth: 0
@@ -107,7 +107,7 @@ jobs:
           echo "latest=$latest"
           echo "latest=$latest" >> $GITHUB_OUTPUT
       - name: Download digests
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v5
         with:
           path: /tmp/digests
           pattern: digests-*

.github/workflows/lint.yml

@@ -22,15 +22,15 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           fetch-depth: 0
       - name: Setup Go
         uses: actions/setup-go@v5
         with:
-          go-version: ^1.24
+          go-version: ^1.25
       - name: golangci-lint
-        uses: golangci/golangci-lint-action@v6
+        uses: golangci/golangci-lint-action@v8
         with:
           version: latest
           args: --timeout=30m

.github/workflows/linux.yml

@@ -7,6 +7,11 @@ on:
         description: "Version name"
         required: true
         type: string
+      forceBeta:
+        description: "Force beta"
+        required: false
+        type: boolean
+        default: false
   release:
     types:
       - published
@@ -19,13 +24,13 @@ jobs:
       version: ${{ steps.outputs.outputs.version }}
     steps:
       - name: Checkout
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           fetch-depth: 0
       - name: Setup Go
         uses: actions/setup-go@v5
         with:
-          go-version: ^1.24
+          go-version: ^1.25.1
       - name: Check input version
         if: github.event_name == 'workflow_dispatch'
         run: |-
@@ -60,13 +65,13 @@ jobs:
           - { os: linux, arch: loong64, debian: loongarch64, rpm: loongarch64 }
     steps:
       - name: Checkout
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           fetch-depth: 0
       - name: Setup Go
         uses: actions/setup-go@v5
         with:
-          go-version: ^1.24
+          go-version: ^1.25.1
       - name: Setup Android NDK
         if: matrix.os == 'android'
         uses: nttld/setup-ndk@v1
@@ -87,7 +92,7 @@ jobs:
           set -xeuo pipefail
           mkdir -p dist
           go build -v -trimpath -o dist/sing-box -tags "${BUILD_TAGS}" \
-          -ldflags '-s -buildid= -X github.com/sagernet/sing-box/constant.Version=${{ needs.calculate_version.outputs.version }}' \
+          -ldflags '-s -buildid= -X github.com/sagernet/sing-box/constant.Version=${{ needs.calculate_version.outputs.version }} -checklinkname=0' \
           ./cmd/sing-box
         env:
           CGO_ENABLED: "0"
@@ -99,11 +104,11 @@ jobs:
         run: |-
           TZ=UTC touch -t '197001010000' dist/sing-box
       - name: Set name
-        if: ${{ ! contains(needs.calculate_version.outputs.version, '-') }}
+        if: (! contains(needs.calculate_version.outputs.version, '-')) && !inputs.forceBeta
         run: |-
           echo "NAME=sing-box" >> "$GITHUB_ENV"
       - name: Set beta name
-        if: contains(needs.calculate_version.outputs.version, '-')
+        if: contains(needs.calculate_version.outputs.version, '-') || inputs.forceBeta
         run: |-
           echo "NAME=sing-box-beta" >> "$GITHUB_ENV"
       - name: Set version
@@ -166,7 +171,7 @@ jobs:
       - build
     steps:
       - name: Checkout
-        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           fetch-depth: 0
       - name: Set tag
@@ -175,7 +180,7 @@ jobs:
           git tag v${{ needs.calculate_version.outputs.version }} -f
           echo "VERSION=${{ needs.calculate_version.outputs.version }}" >> "$GITHUB_ENV"
       - name: Download builds
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v5
         with:
           path: dist
           merge-multiple: true

.golangci.yml

@@ -1,27 +1,6 @@
-linters:
-  disable-all: true
-  enable:
-    - gofumpt
-    - govet
-    - gci
-    - staticcheck
-    - paralleltest
-    - ineffassign
-
-linters-settings:
-  gci:
-    custom-order: true
-    sections:
-      - standard
-      - prefix(github.com/sagernet/)
-      - default
-  staticcheck:
-    checks:
-      - all
-      - -SA1003
-
+version: "2"
 run:
-  go: "1.23"
+  go: "1.25"
   build-tags:
     - with_gvisor
     - with_quic
@@ -30,7 +9,51 @@ run:
     - with_utls
     - with_acme
     - with_clash_api
-
-issues:
-  exclude-dirs:
-    - transport/simple-obfs
+linters:
+  default: none
+  enable:
+    - govet
+    - ineffassign
+    - paralleltest
+    - staticcheck
+  settings:
+    staticcheck:
+      checks:
+        - all
+        - -S1000
+        - -S1008
+        - -S1017
+        - -ST1003
+        - -QF1001
+        - -QF1003
+        - -QF1008
+  exclusions:
+    generated: lax
+    presets:
+      - comments
+      - common-false-positives
+      - legacy
+      - std-error-handling
+    paths:
+      - transport/simple-obfs
+      - third_party$
+      - builtin$
+      - examples$
+formatters:
+  enable:
+    - gci
+    - gofumpt
+  settings:
+    gci:
+      sections:
+        - standard
+        - prefix(github.com/sagernet/)
+        - default
+      custom-order: true
+  exclusions:
+    generated: lax
+    paths:
+      - transport/simple-obfs
+      - third_party$
+      - builtin$
+      - examples$

Dockerfile

@@ -1,4 +1,4 @@
-FROM --platform=$BUILDPLATFORM golang:1.24-alpine AS builder
+FROM --platform=$BUILDPLATFORM golang:1.25-alpine AS builder
 LABEL maintainer="nekohasekai <contact-git@sekai.icu>"
 COPY . /go/src/github.com/sagernet/sing-box
 WORKDIR /go/src/github.com/sagernet/sing-box
@@ -15,7 +15,7 @@ RUN set -ex \
     && go build -v -trimpath -tags \
         "with_gvisor,with_quic,with_dhcp,with_wireguard,with_utls,with_acme,with_clash_api,with_tailscale" \
         -o /go/bin/sing-box \
-        -ldflags "-X \"github.com/sagernet/sing-box/constant.Version=$VERSION\" -s -w -buildid=" \
+        -ldflags "-X \"github.com/sagernet/sing-box/constant.Version=$VERSION\" -s -w -buildid= -checklinkname=0" \
         ./cmd/sing-box
 FROM --platform=$TARGETPLATFORM alpine AS dist
 LABEL maintainer="nekohasekai <contact-git@sekai.icu>"

Makefile

@@ -6,7 +6,7 @@ GOHOSTOS = $(shell go env GOHOSTOS)
 GOHOSTARCH = $(shell go env GOHOSTARCH)
 VERSION=$(shell CGO_ENABLED=0 GOOS=$(GOHOSTOS) GOARCH=$(GOHOSTARCH) go run github.com/sagernet/sing-box/cmd/internal/read_tag@latest)
 
-PARAMS = -v -trimpath -ldflags "-X 'github.com/sagernet/sing-box/constant.Version=$(VERSION)' -s -w -buildid="
+PARAMS = -v -trimpath -ldflags "-X 'github.com/sagernet/sing-box/constant.Version=$(VERSION)' -s -w -buildid= -checklinkname=0"
 MAIN_PARAMS = $(PARAMS) -tags "$(TAGS)"
 MAIN = ./cmd/sing-box
 PREFIX ?= $(shell go env GOPATH)
@@ -17,6 +17,10 @@ build:
 	export GOTOOLCHAIN=local && \
 	go build $(MAIN_PARAMS) $(MAIN)
 
+race:
+	export GOTOOLCHAIN=local && \
+	go build -race $(MAIN_PARAMS) $(MAIN)
+
 ci_build:
 	export GOTOOLCHAIN=local && \
 	go build $(PARAMS) $(MAIN) && \
@@ -45,7 +49,7 @@ lint:
 	GOOS=freebsd golangci-lint run ./...
 
 lint_install:
-	go install -v github.com/golangci/golangci-lint/cmd/golangci-lint@latest
+	go install -v github.com/golangci/golangci-lint/v2/cmd/golangci-lint@latest
 
 proto:
 	@go run ./cmd/internal/protogen
@@ -245,8 +249,8 @@ lib:
 	go run ./cmd/internal/build_libbox -target ios
 
 lib_install:
-	go install -v github.com/sagernet/gomobile/cmd/gomobile@v0.1.6
-	go install -v github.com/sagernet/gomobile/cmd/gobind@v0.1.6
+	go install -v github.com/sagernet/gomobile/cmd/gomobile@v0.1.8
+	go install -v github.com/sagernet/gomobile/cmd/gobind@v0.1.8
 
 docs:
 	venv/bin/mkdocs serve

adapter/dns.go

@@ -3,7 +3,6 @@ package adapter
 import (
 	"context"
 	"net/netip"
-	"time"
 
 	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/log"
@@ -37,7 +36,6 @@ type DNSQueryOptions struct {
 	Transport      DNSTransport
 	Strategy       C.DomainStrategy
 	LookupStrategy C.DomainStrategy
-	Timeout        time.Duration
 	DisableCache   bool
 	RewriteTTL     *uint32
 	ClientSubnet   netip.Prefix
@@ -55,7 +53,6 @@ func DNSQueryOptionsFrom(ctx context.Context, options *option.DomainResolveOptio
 	return &DNSQueryOptions{
 		Transport:    transport,
 		Strategy:     C.DomainStrategy(options.Strategy),
-		Timeout:      time.Duration(options.Timeout),
 		DisableCache: options.DisableCache,
 		RewriteTTL:   options.RewriteTTL,
 		ClientSubnet: options.ClientSubnet.Build(netip.Prefix{}),
@@ -73,7 +70,6 @@ type DNSTransport interface {
 	Type() string
 	Tag() string
 	Dependencies() []string
-	HasDetour() bool
 	Exchange(ctx context.Context, message *dns.Msg) (*dns.Msg, error)
 }
 

adapter/inbound.go

@@ -57,6 +57,7 @@ type InboundContext struct {
 	Domain       string
 	Client       string
 	SniffContext any
+	SnifferNames []string
 	SniffError   error
 
 	// cache
@@ -135,8 +136,7 @@ func ExtendContext(ctx context.Context) (context.Context, *InboundContext) {
 
 func OverrideContext(ctx context.Context) context.Context {
 	if metadata := ContextFrom(ctx); metadata != nil {
-		var newMetadata InboundContext
-		newMetadata = *metadata
+		newMetadata := *metadata
 		return WithContext(ctx, &newMetadata)
 	}
 	return ctx

adapter/network.go

@@ -20,6 +20,7 @@ type NetworkManager interface {
 	DefaultOptions() NetworkOptions
 	RegisterAutoRedirectOutputMark(mark uint32) error
 	AutoRedirectOutputMark() uint32
+	AutoRedirectOutputMarkFunc() control.Func
 	NetworkMonitor() tun.NetworkUpdateMonitor
 	InterfaceMonitor() tun.DefaultInterfaceMonitor
 	PackageManager() tun.PackageManager

adapter/outbound.go

@@ -2,9 +2,12 @@ package adapter
 
 import (
 	"context"
+	"net/netip"
+	"time"
 
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing-tun"
 	N "github.com/sagernet/sing/common/network"
 )
 
@@ -18,6 +21,17 @@ type Outbound interface {
 	N.Dialer
 }
 
+type OutboundWithPreferredRoutes interface {
+	Outbound
+	PreferredDomain(domain string) bool
+	PreferredAddress(address netip.Addr) bool
+}
+
+type DirectRouteOutbound interface {
+	Outbound
+	NewDirectRouteConnection(metadata InboundContext, routeContext tun.DirectRouteContext, timeout time.Duration) (tun.DirectRouteDestination, error)
+}
+
 type OutboundRegistry interface {
 	option.OutboundOptionsRegistry
 	CreateOutbound(ctx context.Context, router Router, logger log.ContextLogger, tag string, outboundType string, options any) (Outbound, error)

adapter/outbound/manager.go

@@ -30,7 +30,7 @@ type Manager struct {
 	outboundByTag           map[string]adapter.Outbound
 	dependByTag             map[string][]string
 	defaultOutbound         adapter.Outbound
-	defaultOutboundFallback adapter.Outbound
+	defaultOutboundFallback func() (adapter.Outbound, error)
 }
 
 func NewManager(logger logger.ContextLogger, registry adapter.OutboundRegistry, endpoint adapter.EndpointManager, defaultTag string) *Manager {
@@ -44,7 +44,7 @@ func NewManager(logger logger.ContextLogger, registry adapter.OutboundRegistry,
 	}
 }
 
-func (m *Manager) Initialize(defaultOutboundFallback adapter.Outbound) {
+func (m *Manager) Initialize(defaultOutboundFallback func() (adapter.Outbound, error)) {
 	m.defaultOutboundFallback = defaultOutboundFallback
 }
 
@@ -55,18 +55,31 @@ func (m *Manager) Start(stage adapter.StartStage) error {
 	}
 	m.started = true
 	m.stage = stage
-	outbounds := m.outbounds
-	m.access.Unlock()
 	if stage == adapter.StartStateStart {
 		if m.defaultTag != "" && m.defaultOutbound == nil {
 			defaultEndpoint, loaded := m.endpoint.Get(m.defaultTag)
 			if !loaded {
+				m.access.Unlock()
 				return E.New("default outbound not found: ", m.defaultTag)
 			}
 			m.defaultOutbound = defaultEndpoint
 		}
+		if m.defaultOutbound == nil {
+			directOutbound, err := m.defaultOutboundFallback()
+			if err != nil {
+				m.access.Unlock()
+				return E.Cause(err, "create direct outbound for fallback")
+			}
+			m.outbounds = append(m.outbounds, directOutbound)
+			m.outboundByTag[directOutbound.Tag()] = directOutbound
+			m.defaultOutbound = directOutbound
+		}
+		outbounds := m.outbounds
+		m.access.Unlock()
 		return m.startOutbounds(append(outbounds, common.Map(m.endpoint.Endpoints(), func(it adapter.Endpoint) adapter.Outbound { return it })...))
 	} else {
+		outbounds := m.outbounds
+		m.access.Unlock()
 		for _, outbound := range outbounds {
 			err := adapter.LegacyStart(outbound, stage)
 			if err != nil {
@@ -187,11 +200,7 @@ func (m *Manager) Outbound(tag string) (adapter.Outbound, bool) {
 func (m *Manager) Default() adapter.Outbound {
 	m.access.RLock()
 	defer m.access.RUnlock()
-	if m.defaultOutbound != nil {
-		return m.defaultOutbound
-	} else {
-		return m.defaultOutboundFallback
-	}
+	return m.defaultOutbound
 }
 
 func (m *Manager) Remove(tag string) error {

adapter/router.go

@@ -6,8 +6,10 @@ import (
 	"net"
 	"net/http"
 	"sync"
+	"time"
 
 	C "github.com/sagernet/sing-box/constant"
+	"github.com/sagernet/sing-tun"
 	M "github.com/sagernet/sing/common/metadata"
 	N "github.com/sagernet/sing/common/network"
 	"github.com/sagernet/sing/common/ntp"
@@ -19,7 +21,7 @@ import (
 type Router interface {
 	Lifecycle
 	ConnectionRouter
-	PreMatch(metadata InboundContext) error
+	PreMatch(metadata InboundContext, context tun.DirectRouteContext, timeout time.Duration) (tun.DirectRouteDestination, error)
 	ConnectionRouterEx
 	RuleSet(tag string) (RuleSet, bool)
 	NeedWIFIState() bool

adapter/upstream_legacy.go

@@ -78,8 +78,8 @@ func (w *myUpstreamHandlerWrapper) NewError(ctx context.Context, err error) {
 // Deprecated: removed
 func UpstreamMetadata(metadata InboundContext) M.Metadata {
 	return M.Metadata{
-		Source:      metadata.Source,
-		Destination: metadata.Destination,
+		Source:      metadata.Source.Unwrap(),
+		Destination: metadata.Destination.Unwrap(),
 	}
 }
 

box.go

@@ -314,22 +314,23 @@ func New(options Options) (*Box, error) {
 			return nil, E.Cause(err, "initialize service[", i, "]")
 		}
 	}
-	outboundManager.Initialize(common.Must1(
-		direct.NewOutbound(
+	outboundManager.Initialize(func() (adapter.Outbound, error) {
+		return direct.NewOutbound(
 			ctx,
 			router,
 			logFactory.NewLogger("outbound/direct"),
 			"direct",
 			option.DirectOutboundOptions{},
-		),
-	))
-	dnsTransportManager.Initialize(common.Must1(
-		local.NewTransport(
+		)
+	})
+	dnsTransportManager.Initialize(func() (adapter.DNSTransport, error) {
+		return local.NewTransport(
 			ctx,
 			logFactory.NewLogger("dns/local"),
 			"local",
 			option.LocalDNSServerOptions{},
-		)))
+		)
+	})
 	if platformInterface != nil {
 		err = platformInterface.Initialize(networkManager)
 		if err != nil {

cmd/internal/app_store_connect/main.go

@@ -134,6 +134,7 @@ func publishTestflight(ctx context.Context) error {
 			asc.PlatformTVOS,
 		}
 	}
+	waitingForProcess := false
 	for _, platform := range platforms {
 		log.Info(string(platform), " list builds")
 		for {
@@ -145,12 +146,13 @@ func publishTestflight(ctx context.Context) error {
 				return err
 			}
 			build := builds.Data[0]
-			if common.Contains(buildIDs, build.ID) || time.Since(build.Attributes.UploadedDate.Time) > 30*time.Minute {
+			if !waitingForProcess && (common.Contains(buildIDs, build.ID) || time.Since(build.Attributes.UploadedDate.Time) > 30*time.Minute) {
 				log.Info(string(platform), " ", tag, " waiting for process")
 				time.Sleep(15 * time.Second)
 				continue
 			}
 			if *build.Attributes.ProcessingState != "VALID" {
+				waitingForProcess = true
 				log.Info(string(platform), " ", tag, " waiting for process: ", *build.Attributes.ProcessingState)
 				time.Sleep(15 * time.Second)
 				continue
@@ -177,7 +179,7 @@ func publishTestflight(ctx context.Context) error {
 			}
 			log.Info(string(platform), " ", tag, " publish")
 			response, err := client.TestFlight.AddBuildsToBetaGroup(ctx, groupID, []string{build.ID})
-			if response != nil && response.StatusCode == http.StatusUnprocessableEntity {
+			if response != nil && (response.StatusCode == http.StatusUnprocessableEntity || response.StatusCode == http.StatusNotFound) {
 				log.Info("waiting for process")
 				time.Sleep(15 * time.Second)
 				continue

cmd/internal/build_libbox/main.go

@@ -46,8 +46,9 @@ var (
 	sharedFlags []string
 	debugFlags  []string
 	sharedTags  []string
-	iosTags     []string
+	macOSTags   []string
 	memcTags    []string
+	notMemcTags []string
 	debugTags   []string
 )
 
@@ -58,12 +59,13 @@ func init() {
 	if err != nil {
 		currentTag = "unknown"
 	}
-	sharedFlags = append(sharedFlags, "-ldflags", "-X github.com/sagernet/sing-box/constant.Version="+currentTag+" -s -w -buildid=")
-	debugFlags = append(debugFlags, "-ldflags", "-X github.com/sagernet/sing-box/constant.Version="+currentTag)
+	sharedFlags = append(sharedFlags, "-ldflags", "-X github.com/sagernet/sing-box/constant.Version="+currentTag+" -s -w -buildid=  -checklinkname=0")
+	debugFlags = append(debugFlags, "-ldflags", "-X github.com/sagernet/sing-box/constant.Version="+currentTag+" -checklinkname=0")
 
 	sharedTags = append(sharedTags, "with_gvisor", "with_quic", "with_wireguard", "with_utls", "with_clash_api", "with_conntrack")
-	iosTags = append(iosTags, "with_dhcp", "with_low_memory")
+	macOSTags = append(macOSTags, "with_dhcp")
 	memcTags = append(memcTags, "with_tailscale")
+	notMemcTags = append(notMemcTags, "with_low_memory")
 	debugTags = append(debugTags, "debug")
 }
 
@@ -105,8 +107,10 @@ func buildAndroid() {
 	}
 
 	if !debugEnabled {
+		// sharedFlags[3] = sharedFlags[3] + " -checklinkname=0"
 		args = append(args, sharedFlags...)
 	} else {
+		// debugFlags[1] = debugFlags[1] + " -checklinkname=0"
 		args = append(args, debugFlags...)
 	}
 
@@ -153,9 +157,12 @@ func buildApple() {
 		"-v",
 		"-target", bindTarget,
 		"-libname=box",
+		"-tags-not-macos=with_low_memory",
 	}
 	if !withTailscale {
-		args = append(args, "-tags-macos="+strings.Join(memcTags, ","))
+		args = append(args, "-tags-macos="+strings.Join(append(macOSTags, memcTags...), ","))
+	} else {
+		args = append(args, "-tags-macos="+strings.Join(macOSTags, ","))
 	}
 
 	if !debugEnabled {
@@ -164,7 +171,7 @@ func buildApple() {
 		args = append(args, debugFlags...)
 	}
 
-	tags := append(sharedTags, iosTags...)
+	tags := sharedTags
 	if withTailscale {
 		tags = append(tags, memcTags...)
 	}

cmd/internal/tun_bench/main.go

@@ -0,0 +1,284 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net/netip"
+	"os"
+	"os/exec"
+	"strings"
+	"syscall"
+	"time"
+
+	C "github.com/sagernet/sing-box/constant"
+	"github.com/sagernet/sing-box/include"
+	"github.com/sagernet/sing-box/log"
+	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing/common"
+	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/json"
+	"github.com/sagernet/sing/common/shell"
+)
+
+var iperf3Path string
+
+func main() {
+	err := main0()
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func main0() error {
+	err := shell.Exec("sudo", "ls").Run()
+	if err != nil {
+		return err
+	}
+	results, err := runTests()
+	if err != nil {
+		return err
+	}
+	encoder := json.NewEncoder(os.Stdout)
+	encoder.SetIndent("", "  ")
+	return encoder.Encode(results)
+}
+
+func runTests() ([]TestResult, error) {
+	boxPaths := []string{
+		os.ExpandEnv("$HOME/Downloads/sing-box-1.11.15-darwin-arm64/sing-box"),
+		//"/Users/sekai/Downloads/sing-box-1.11.15-linux-arm64/sing-box",
+		"./sing-box",
+	}
+	stacks := []string{
+		"gvisor",
+		"system",
+	}
+	mtus := []int{
+		1500,
+		4064,
+		// 16384,
+		// 32768,
+		// 49152,
+		65535,
+	}
+	flagList := [][]string{
+		{},
+	}
+	var results []TestResult
+	for _, boxPath := range boxPaths {
+		for _, stack := range stacks {
+			for _, mtu := range mtus {
+				if strings.HasPrefix(boxPath, ".") {
+					for _, flags := range flagList {
+						result, err := testOnce(boxPath, stack, mtu, false, flags)
+						if err != nil {
+							return nil, err
+						}
+						results = append(results, *result)
+					}
+				} else {
+					result, err := testOnce(boxPath, stack, mtu, false, nil)
+					if err != nil {
+						return nil, err
+					}
+					results = append(results, *result)
+				}
+			}
+		}
+	}
+	return results, nil
+}
+
+type TestResult struct {
+	BoxPath       string   `json:"box_path"`
+	Stack         string   `json:"stack"`
+	MTU           int      `json:"mtu"`
+	Flags         []string `json:"flags"`
+	MultiThread   bool     `json:"multi_thread"`
+	UploadSpeed   string   `json:"upload_speed"`
+	DownloadSpeed string   `json:"download_speed"`
+}
+
+func testOnce(boxPath string, stackName string, mtu int, multiThread bool, flags []string) (result *TestResult, err error) {
+	testAddress := netip.MustParseAddr("1.1.1.1")
+	testConfig := option.Options{
+		Inbounds: []option.Inbound{
+			{
+				Type: C.TypeTun,
+				Options: &option.TunInboundOptions{
+					Address:      []netip.Prefix{netip.MustParsePrefix("172.18.0.1/30")},
+					AutoRoute:    true,
+					MTU:          uint32(mtu),
+					Stack:        stackName,
+					RouteAddress: []netip.Prefix{netip.PrefixFrom(testAddress, testAddress.BitLen())},
+				},
+			},
+		},
+		Route: &option.RouteOptions{
+			Rules: []option.Rule{
+				{
+					Type: C.RuleTypeDefault,
+					DefaultOptions: option.DefaultRule{
+						RawDefaultRule: option.RawDefaultRule{
+							IPCIDR: []string{testAddress.String()},
+						},
+						RuleAction: option.RuleAction{
+							Action: C.RuleActionTypeRouteOptions,
+							RouteOptionsOptions: option.RouteOptionsActionOptions{
+								OverrideAddress: "127.0.0.1",
+							},
+						},
+					},
+				},
+			},
+			AutoDetectInterface: true,
+		},
+	}
+	ctx := include.Context(context.Background())
+	tempConfig, err := os.CreateTemp("", "tun-bench-*.json")
+	if err != nil {
+		return
+	}
+	defer os.Remove(tempConfig.Name())
+	encoder := json.NewEncoderContext(ctx, tempConfig)
+	encoder.SetIndent("", "  ")
+	err = encoder.Encode(testConfig)
+	if err != nil {
+		return nil, E.Cause(err, "encode test config")
+	}
+	tempConfig.Close()
+	var sudoArgs []string
+	if len(flags) > 0 {
+		sudoArgs = append(sudoArgs, "env")
+		sudoArgs = append(sudoArgs, flags...)
+	}
+	sudoArgs = append(sudoArgs, boxPath, "run", "-c", tempConfig.Name())
+	boxProcess := shell.Exec("sudo", sudoArgs...)
+	boxProcess.Stdout = &stderrWriter{}
+	boxProcess.Stderr = io.Discard
+	err = boxProcess.Start()
+	if err != nil {
+		return
+	}
+
+	if C.IsDarwin {
+		iperf3Path, err = exec.LookPath("iperf3-darwin")
+	} else {
+		iperf3Path, err = exec.LookPath("iperf3")
+	}
+	if err != nil {
+		return
+	}
+	serverProcess := shell.Exec(iperf3Path, "-s")
+	serverProcess.Stdout = io.Discard
+	serverProcess.Stderr = io.Discard
+	err = serverProcess.Start()
+	if err != nil {
+		return nil, E.Cause(err, "start iperf3 server")
+	}
+
+	time.Sleep(time.Second)
+
+	args := []string{"-c", testAddress.String()}
+	if multiThread {
+		args = append(args, "-P", "10")
+	}
+
+	uploadProcess := shell.Exec(iperf3Path, args...)
+	output, err := uploadProcess.Read()
+	if err != nil {
+		boxProcess.Process.Signal(syscall.SIGKILL)
+		serverProcess.Process.Signal(syscall.SIGKILL)
+		println(output)
+		return
+	}
+
+	uploadResult := common.SubstringBeforeLast(output, "iperf Done.")
+	uploadResult = common.SubstringBeforeLast(uploadResult, "sender")
+	uploadResult = common.SubstringBeforeLast(uploadResult, "bits/sec")
+	uploadResult = common.SubstringAfterLast(uploadResult, "Bytes")
+	uploadResult = strings.ReplaceAll(uploadResult, " ", "")
+
+	result = &TestResult{
+		BoxPath:     boxPath,
+		Stack:       stackName,
+		MTU:         mtu,
+		Flags:       flags,
+		MultiThread: multiThread,
+		UploadSpeed: uploadResult,
+	}
+
+	downloadProcess := shell.Exec(iperf3Path, append(args, "-R")...)
+	output, err = downloadProcess.Read()
+	if err != nil {
+		boxProcess.Process.Signal(syscall.SIGKILL)
+		serverProcess.Process.Signal(syscall.SIGKILL)
+		println(output)
+		return
+	}
+
+	downloadResult := common.SubstringBeforeLast(output, "iperf Done.")
+	downloadResult = common.SubstringBeforeLast(downloadResult, "receiver")
+	downloadResult = common.SubstringBeforeLast(downloadResult, "bits/sec")
+	downloadResult = common.SubstringAfterLast(downloadResult, "Bytes")
+	downloadResult = strings.ReplaceAll(downloadResult, " ", "")
+
+	result.DownloadSpeed = downloadResult
+
+	printArgs := []any{boxPath, stackName, mtu, "upload", uploadResult, "download", downloadResult}
+	if len(flags) > 0 {
+		printArgs = append(printArgs, "flags", strings.Join(flags, " "))
+	}
+	if multiThread {
+		printArgs = append(printArgs, "(-P 10)")
+	}
+	fmt.Println(printArgs...)
+	err = boxProcess.Process.Signal(syscall.SIGTERM)
+	if err != nil {
+		return
+	}
+
+	err = serverProcess.Process.Signal(syscall.SIGTERM)
+	if err != nil {
+		return
+	}
+
+	boxDone := make(chan struct{})
+	go func() {
+		boxProcess.Cmd.Wait()
+		close(boxDone)
+	}()
+
+	serverDone := make(chan struct{})
+	go func() {
+		serverProcess.Process.Wait()
+		close(serverDone)
+	}()
+
+	select {
+	case <-boxDone:
+	case <-time.After(2 * time.Second):
+		boxProcess.Process.Kill()
+	case <-time.After(4 * time.Second):
+		println("box process did not close!")
+		os.Exit(1)
+	}
+
+	select {
+	case <-serverDone:
+	case <-time.After(2 * time.Second):
+		serverProcess.Process.Kill()
+	case <-time.After(4 * time.Second):
+		println("server process did not close!")
+		os.Exit(1)
+	}
+
+	return
+}
+
+type stderrWriter struct{}
+
+func (w *stderrWriter) Write(p []byte) (n int, err error) {
+	return os.Stderr.Write(p)
+}

cmd/sing-box/cmd_rule_set_compile.go

@@ -6,8 +6,10 @@ import (
 	"strings"
 
 	"github.com/sagernet/sing-box/common/srs"
+	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing-box/route/rule"
 	"github.com/sagernet/sing/common/json"
 
 	"github.com/spf13/cobra"
@@ -69,7 +71,7 @@ func compileRuleSet(sourcePath string) error {
 	if err != nil {
 		return err
 	}
-	err = srs.Write(outputFile, plainRuleSet.Options, plainRuleSet.Version)
+	err = srs.Write(outputFile, plainRuleSet.Options, downgradeRuleSetVersion(plainRuleSet.Version, plainRuleSet.Options))
 	if err != nil {
 		outputFile.Close()
 		os.Remove(outputPath)
@@ -78,3 +80,18 @@ func compileRuleSet(sourcePath string) error {
 	outputFile.Close()
 	return nil
 }
+
+func downgradeRuleSetVersion(version uint8, options option.PlainRuleSet) uint8 {
+	if version == C.RuleSetVersion4 && !rule.HasHeadlessRule(options.Rules, func(rule option.DefaultHeadlessRule) bool {
+		return rule.NetworkInterfaceAddress != nil && rule.NetworkInterfaceAddress.Size() > 0 ||
+			len(rule.DefaultInterfaceAddress) > 0
+	}) {
+		version = C.RuleSetVersion3
+	}
+	if version == C.RuleSetVersion3 && !rule.HasHeadlessRule(options.Rules, func(rule option.DefaultHeadlessRule) bool {
+		return len(rule.NetworkType) > 0 || rule.NetworkIsExpensive || rule.NetworkIsConstrained
+	}) {
+		version = C.RuleSetVersion2
+	}
+	return version
+}

cmd/sing-box/cmd_tools_fetch_http3.go

@@ -22,7 +22,7 @@ func initializeHTTP3Client(instance *box.Box) error {
 	}
 	http3Client = &http.Client{
 		Transport: &http3.Transport{
-			Dial: func(ctx context.Context, addr string, tlsCfg *tls.Config, cfg *quic.Config) (quic.EarlyConnection, error) {
+			Dial: func(ctx context.Context, addr string, tlsCfg *tls.Config, cfg *quic.Config) (*quic.Conn, error) {
 				destination := M.ParseSocksaddr(addr)
 				udpConn, dErr := dialer.DialContext(ctx, N.NetworkUDP, destination)
 				if dErr != nil {

common/badtls/raw_conn.go

@@ -0,0 +1,176 @@
+//go:build go1.25 && !without_badtls
+
+package badtls
+
+import (
+	"bytes"
+	"os"
+	"reflect"
+	"sync/atomic"
+	"unsafe"
+
+	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/tls"
+)
+
+type RawConn struct {
+	pointer unsafe.Pointer
+	methods *Methods
+
+	IsClient            *bool
+	IsHandshakeComplete *atomic.Bool
+	Vers                *uint16
+	CipherSuite         *uint16
+
+	RawInput *bytes.Buffer
+	Input    *bytes.Reader
+	Hand     *bytes.Buffer
+
+	CloseNotifySent *bool
+	CloseNotifyErr  *error
+
+	In  *RawHalfConn
+	Out *RawHalfConn
+
+	BytesSent   *int64
+	PacketsSent *int64
+
+	ActiveCall *atomic.Int32
+	Tmp        *[16]byte
+}
+
+func NewRawConn(rawTLSConn tls.Conn) (*RawConn, error) {
+	var (
+		pointer unsafe.Pointer
+		methods *Methods
+		loaded  bool
+	)
+	for _, tlsCreator := range methodRegistry {
+		pointer, methods, loaded = tlsCreator(rawTLSConn)
+		if loaded {
+			break
+		}
+	}
+	if !loaded {
+		return nil, os.ErrInvalid
+	}
+
+	conn := &RawConn{
+		pointer: pointer,
+		methods: methods,
+	}
+
+	rawConn := reflect.Indirect(reflect.ValueOf(rawTLSConn))
+
+	rawIsClient := rawConn.FieldByName("isClient")
+	if !rawIsClient.IsValid() || rawIsClient.Kind() != reflect.Bool {
+		return nil, E.New("invalid Conn.isClient")
+	}
+	conn.IsClient = (*bool)(unsafe.Pointer(rawIsClient.UnsafeAddr()))
+
+	rawIsHandshakeComplete := rawConn.FieldByName("isHandshakeComplete")
+	if !rawIsHandshakeComplete.IsValid() || rawIsHandshakeComplete.Kind() != reflect.Struct {
+		return nil, E.New("invalid Conn.isHandshakeComplete")
+	}
+	conn.IsHandshakeComplete = (*atomic.Bool)(unsafe.Pointer(rawIsHandshakeComplete.UnsafeAddr()))
+
+	rawVers := rawConn.FieldByName("vers")
+	if !rawVers.IsValid() || rawVers.Kind() != reflect.Uint16 {
+		return nil, E.New("invalid Conn.vers")
+	}
+	conn.Vers = (*uint16)(unsafe.Pointer(rawVers.UnsafeAddr()))
+
+	rawCipherSuite := rawConn.FieldByName("cipherSuite")
+	if !rawCipherSuite.IsValid() || rawCipherSuite.Kind() != reflect.Uint16 {
+		return nil, E.New("invalid Conn.cipherSuite")
+	}
+	conn.CipherSuite = (*uint16)(unsafe.Pointer(rawCipherSuite.UnsafeAddr()))
+
+	rawRawInput := rawConn.FieldByName("rawInput")
+	if !rawRawInput.IsValid() || rawRawInput.Kind() != reflect.Struct {
+		return nil, E.New("invalid Conn.rawInput")
+	}
+	conn.RawInput = (*bytes.Buffer)(unsafe.Pointer(rawRawInput.UnsafeAddr()))
+
+	rawInput := rawConn.FieldByName("input")
+	if !rawInput.IsValid() || rawInput.Kind() != reflect.Struct {
+		return nil, E.New("invalid Conn.input")
+	}
+	conn.Input = (*bytes.Reader)(unsafe.Pointer(rawInput.UnsafeAddr()))
+
+	rawHand := rawConn.FieldByName("hand")
+	if !rawHand.IsValid() || rawHand.Kind() != reflect.Struct {
+		return nil, E.New("invalid Conn.hand")
+	}
+	conn.Hand = (*bytes.Buffer)(unsafe.Pointer(rawHand.UnsafeAddr()))
+
+	rawCloseNotifySent := rawConn.FieldByName("closeNotifySent")
+	if !rawCloseNotifySent.IsValid() || rawCloseNotifySent.Kind() != reflect.Bool {
+		return nil, E.New("invalid Conn.closeNotifySent")
+	}
+	conn.CloseNotifySent = (*bool)(unsafe.Pointer(rawCloseNotifySent.UnsafeAddr()))
+
+	rawCloseNotifyErr := rawConn.FieldByName("closeNotifyErr")
+	if !rawCloseNotifyErr.IsValid() || rawCloseNotifyErr.Kind() != reflect.Interface {
+		return nil, E.New("invalid Conn.closeNotifyErr")
+	}
+	conn.CloseNotifyErr = (*error)(unsafe.Pointer(rawCloseNotifyErr.UnsafeAddr()))
+
+	rawIn := rawConn.FieldByName("in")
+	if !rawIn.IsValid() || rawIn.Kind() != reflect.Struct {
+		return nil, E.New("invalid Conn.in")
+	}
+	halfIn, err := NewRawHalfConn(rawIn, methods)
+	if err != nil {
+		return nil, E.Cause(err, "invalid Conn.in")
+	}
+	conn.In = halfIn
+
+	rawOut := rawConn.FieldByName("out")
+	if !rawOut.IsValid() || rawOut.Kind() != reflect.Struct {
+		return nil, E.New("invalid Conn.out")
+	}
+	halfOut, err := NewRawHalfConn(rawOut, methods)
+	if err != nil {
+		return nil, E.Cause(err, "invalid Conn.out")
+	}
+	conn.Out = halfOut
+
+	rawBytesSent := rawConn.FieldByName("bytesSent")
+	if !rawBytesSent.IsValid() || rawBytesSent.Kind() != reflect.Int64 {
+		return nil, E.New("invalid Conn.bytesSent")
+	}
+	conn.BytesSent = (*int64)(unsafe.Pointer(rawBytesSent.UnsafeAddr()))
+
+	rawPacketsSent := rawConn.FieldByName("packetsSent")
+	if !rawPacketsSent.IsValid() || rawPacketsSent.Kind() != reflect.Int64 {
+		return nil, E.New("invalid Conn.packetsSent")
+	}
+	conn.PacketsSent = (*int64)(unsafe.Pointer(rawPacketsSent.UnsafeAddr()))
+
+	rawActiveCall := rawConn.FieldByName("activeCall")
+	if !rawActiveCall.IsValid() || rawActiveCall.Kind() != reflect.Struct {
+		return nil, E.New("invalid Conn.activeCall")
+	}
+	conn.ActiveCall = (*atomic.Int32)(unsafe.Pointer(rawActiveCall.UnsafeAddr()))
+
+	rawTmp := rawConn.FieldByName("tmp")
+	if !rawTmp.IsValid() || rawTmp.Kind() != reflect.Array || rawTmp.Len() != 16 || rawTmp.Type().Elem().Kind() != reflect.Uint8 {
+		return nil, E.New("invalid Conn.tmp")
+	}
+	conn.Tmp = (*[16]byte)(unsafe.Pointer(rawTmp.UnsafeAddr()))
+
+	return conn, nil
+}
+
+func (c *RawConn) ReadRecord() error {
+	return c.methods.readRecord(c.pointer)
+}
+
+func (c *RawConn) HandlePostHandshakeMessage() error {
+	return c.methods.handlePostHandshakeMessage(c.pointer)
+}
+
+func (c *RawConn) WriteRecordLocked(typ uint16, data []byte) (int, error) {
+	return c.methods.writeRecordLocked(c.pointer, typ, data)
+}

common/badtls/raw_half_conn.go

@@ -0,0 +1,121 @@
+//go:build go1.25 && !without_badtls
+
+package badtls
+
+import (
+	"hash"
+	"reflect"
+	"sync"
+	"unsafe"
+
+	E "github.com/sagernet/sing/common/exceptions"
+)
+
+type RawHalfConn struct {
+	pointer unsafe.Pointer
+	methods *Methods
+	*sync.Mutex
+	Err           *error
+	Version       *uint16
+	Cipher        *any
+	Seq           *[8]byte
+	ScratchBuf    *[13]byte
+	TrafficSecret *[]byte
+	Mac           *hash.Hash
+	RawKey        *[]byte
+	RawIV         *[]byte
+	RawMac        *[]byte
+}
+
+func NewRawHalfConn(rawHalfConn reflect.Value, methods *Methods) (*RawHalfConn, error) {
+	halfConn := &RawHalfConn{
+		pointer: (unsafe.Pointer)(rawHalfConn.UnsafeAddr()),
+		methods: methods,
+	}
+
+	rawMutex := rawHalfConn.FieldByName("Mutex")
+	if !rawMutex.IsValid() || rawMutex.Kind() != reflect.Struct {
+		return nil, E.New("badtls: invalid halfConn.Mutex")
+	}
+	halfConn.Mutex = (*sync.Mutex)(unsafe.Pointer(rawMutex.UnsafeAddr()))
+
+	rawErr := rawHalfConn.FieldByName("err")
+	if !rawErr.IsValid() || rawErr.Kind() != reflect.Interface {
+		return nil, E.New("badtls: invalid halfConn.err")
+	}
+	halfConn.Err = (*error)(unsafe.Pointer(rawErr.UnsafeAddr()))
+
+	rawVersion := rawHalfConn.FieldByName("version")
+	if !rawVersion.IsValid() || rawVersion.Kind() != reflect.Uint16 {
+		return nil, E.New("badtls: invalid halfConn.version")
+	}
+	halfConn.Version = (*uint16)(unsafe.Pointer(rawVersion.UnsafeAddr()))
+
+	rawCipher := rawHalfConn.FieldByName("cipher")
+	if !rawCipher.IsValid() || rawCipher.Kind() != reflect.Interface {
+		return nil, E.New("badtls: invalid halfConn.cipher")
+	}
+	halfConn.Cipher = (*any)(unsafe.Pointer(rawCipher.UnsafeAddr()))
+
+	rawSeq := rawHalfConn.FieldByName("seq")
+	if !rawSeq.IsValid() || rawSeq.Kind() != reflect.Array || rawSeq.Len() != 8 || rawSeq.Type().Elem().Kind() != reflect.Uint8 {
+		return nil, E.New("badtls: invalid halfConn.seq")
+	}
+	halfConn.Seq = (*[8]byte)(unsafe.Pointer(rawSeq.UnsafeAddr()))
+
+	rawScratchBuf := rawHalfConn.FieldByName("scratchBuf")
+	if !rawScratchBuf.IsValid() || rawScratchBuf.Kind() != reflect.Array || rawScratchBuf.Len() != 13 || rawScratchBuf.Type().Elem().Kind() != reflect.Uint8 {
+		return nil, E.New("badtls: invalid halfConn.scratchBuf")
+	}
+	halfConn.ScratchBuf = (*[13]byte)(unsafe.Pointer(rawScratchBuf.UnsafeAddr()))
+
+	rawTrafficSecret := rawHalfConn.FieldByName("trafficSecret")
+	if !rawTrafficSecret.IsValid() || rawTrafficSecret.Kind() != reflect.Slice || rawTrafficSecret.Type().Elem().Kind() != reflect.Uint8 {
+		return nil, E.New("badtls: invalid halfConn.trafficSecret")
+	}
+	halfConn.TrafficSecret = (*[]byte)(unsafe.Pointer(rawTrafficSecret.UnsafeAddr()))
+
+	rawMac := rawHalfConn.FieldByName("mac")
+	if !rawMac.IsValid() || rawMac.Kind() != reflect.Interface {
+		return nil, E.New("badtls: invalid halfConn.mac")
+	}
+	halfConn.Mac = (*hash.Hash)(unsafe.Pointer(rawMac.UnsafeAddr()))
+
+	rawKey := rawHalfConn.FieldByName("rawKey")
+	if rawKey.IsValid() {
+		if /*!rawKey.IsValid() || */ rawKey.Kind() != reflect.Slice || rawKey.Type().Elem().Kind() != reflect.Uint8 {
+			return nil, E.New("badtls: invalid halfConn.rawKey")
+		}
+		halfConn.RawKey = (*[]byte)(unsafe.Pointer(rawKey.UnsafeAddr()))
+
+		rawIV := rawHalfConn.FieldByName("rawIV")
+		if !rawIV.IsValid() || rawIV.Kind() != reflect.Slice || rawIV.Type().Elem().Kind() != reflect.Uint8 {
+			return nil, E.New("badtls: invalid halfConn.rawIV")
+		}
+		halfConn.RawIV = (*[]byte)(unsafe.Pointer(rawIV.UnsafeAddr()))
+
+		rawMAC := rawHalfConn.FieldByName("rawMac")
+		if !rawMAC.IsValid() || rawMAC.Kind() != reflect.Slice || rawMAC.Type().Elem().Kind() != reflect.Uint8 {
+			return nil, E.New("badtls: invalid halfConn.rawMac")
+		}
+		halfConn.RawMac = (*[]byte)(unsafe.Pointer(rawMAC.UnsafeAddr()))
+	}
+
+	return halfConn, nil
+}
+
+func (hc *RawHalfConn) Decrypt(record []byte) ([]byte, uint8, error) {
+	return hc.methods.decrypt(hc.pointer, record)
+}
+
+func (hc *RawHalfConn) SetErrorLocked(err error) error {
+	return hc.methods.setErrorLocked(hc.pointer, err)
+}
+
+func (hc *RawHalfConn) SetTrafficSecret(suite unsafe.Pointer, level int, secret []byte) {
+	hc.methods.setTrafficSecret(hc.pointer, suite, level, secret)
+}
+
+func (hc *RawHalfConn) ExplicitNonceLen() int {
+	return hc.methods.explicitNonceLen(hc.pointer)
+}

common/badtls/read_wait.go

@@ -1,18 +1,9 @@
-//go:build go1.21 && !without_badtls
+//go:build go1.25 && !without_badtls
 
 package badtls
 
 import (
-	"bytes"
-	"context"
-	"net"
-	"os"
-	"reflect"
-	"sync"
-	"unsafe"
-
 	"github.com/sagernet/sing/common/buf"
-	E "github.com/sagernet/sing/common/exceptions"
 	N "github.com/sagernet/sing/common/network"
 	"github.com/sagernet/sing/common/tls"
 )
@@ -21,63 +12,21 @@ var _ N.ReadWaiter = (*ReadWaitConn)(nil)
 
 type ReadWaitConn struct {
 	tls.Conn
-	halfAccess                    *sync.Mutex
-	rawInput                      *bytes.Buffer
-	input                         *bytes.Reader
-	hand                          *bytes.Buffer
-	readWaitOptions               N.ReadWaitOptions
-	tlsReadRecord                 func() error
-	tlsHandlePostHandshakeMessage func() error
+	rawConn         *RawConn
+	readWaitOptions N.ReadWaitOptions
 }
 
 func NewReadWaitConn(conn tls.Conn) (tls.Conn, error) {
-	var (
-		loaded                        bool
-		tlsReadRecord                 func() error
-		tlsHandlePostHandshakeMessage func() error
-	)
-	for _, tlsCreator := range tlsRegistry {
-		loaded, tlsReadRecord, tlsHandlePostHandshakeMessage = tlsCreator(conn)
-		if loaded {
-			break
-		}
+	if _, isReadWaitConn := conn.(N.ReadWaiter); isReadWaitConn {
+		return conn, nil
 	}
-	if !loaded {
-		return nil, os.ErrInvalid
+	rawConn, err := NewRawConn(conn)
+	if err != nil {
+		return nil, err
 	}
-	rawConn := reflect.Indirect(reflect.ValueOf(conn))
-	rawHalfConn := rawConn.FieldByName("in")
-	if !rawHalfConn.IsValid() || rawHalfConn.Kind() != reflect.Struct {
-		return nil, E.New("badtls: invalid half conn")
-	}
-	rawHalfMutex := rawHalfConn.FieldByName("Mutex")
-	if !rawHalfMutex.IsValid() || rawHalfMutex.Kind() != reflect.Struct {
-		return nil, E.New("badtls: invalid half mutex")
-	}
-	halfAccess := (*sync.Mutex)(unsafe.Pointer(rawHalfMutex.UnsafeAddr()))
-	rawRawInput := rawConn.FieldByName("rawInput")
-	if !rawRawInput.IsValid() || rawRawInput.Kind() != reflect.Struct {
-		return nil, E.New("badtls: invalid raw input")
-	}
-	rawInput := (*bytes.Buffer)(unsafe.Pointer(rawRawInput.UnsafeAddr()))
-	rawInput0 := rawConn.FieldByName("input")
-	if !rawInput0.IsValid() || rawInput0.Kind() != reflect.Struct {
-		return nil, E.New("badtls: invalid input")
-	}
-	input := (*bytes.Reader)(unsafe.Pointer(rawInput0.UnsafeAddr()))
-	rawHand := rawConn.FieldByName("hand")
-	if !rawHand.IsValid() || rawHand.Kind() != reflect.Struct {
-		return nil, E.New("badtls: invalid hand")
-	}
-	hand := (*bytes.Buffer)(unsafe.Pointer(rawHand.UnsafeAddr()))
 	return &ReadWaitConn{
-		Conn:                          conn,
-		halfAccess:                    halfAccess,
-		rawInput:                      rawInput,
-		input:                         input,
-		hand:                          hand,
-		tlsReadRecord:                 tlsReadRecord,
-		tlsHandlePostHandshakeMessage: tlsHandlePostHandshakeMessage,
+		Conn:    conn,
+		rawConn: rawConn,
 	}, nil
 }
 
@@ -87,36 +36,36 @@ func (c *ReadWaitConn) InitializeReadWaiter(options N.ReadWaitOptions) (needCopy
 }
 
 func (c *ReadWaitConn) WaitReadBuffer() (buffer *buf.Buffer, err error) {
-	err = c.HandshakeContext(context.Background())
-	if err != nil {
-		return
-	}
-	c.halfAccess.Lock()
-	defer c.halfAccess.Unlock()
-	for c.input.Len() == 0 {
-		err = c.tlsReadRecord()
+	//err = c.HandshakeContext(context.Background())
+	//if err != nil {
+	//	return
+	//}
+	c.rawConn.In.Lock()
+	defer c.rawConn.In.Unlock()
+	for c.rawConn.Input.Len() == 0 {
+		err = c.rawConn.ReadRecord()
 		if err != nil {
 			return
 		}
-		for c.hand.Len() > 0 {
-			err = c.tlsHandlePostHandshakeMessage()
+		for c.rawConn.Hand.Len() > 0 {
+			err = c.rawConn.HandlePostHandshakeMessage()
 			if err != nil {
 				return
 			}
 		}
 	}
 	buffer = c.readWaitOptions.NewBuffer()
-	n, err := c.input.Read(buffer.FreeBytes())
+	n, err := c.rawConn.Input.Read(buffer.FreeBytes())
 	if err != nil {
 		buffer.Release()
 		return
 	}
 	buffer.Truncate(n)
 
-	if n != 0 && c.input.Len() == 0 && c.rawInput.Len() > 0 &&
-		// recordType(c.rawInput.Bytes()[0]) == recordTypeAlert {
-		c.rawInput.Bytes()[0] == 21 {
-		_ = c.tlsReadRecord()
+	if n != 0 && c.rawConn.Input.Len() == 0 && c.rawConn.Input.Len() > 0 &&
+		// recordType(c.RawInput.Bytes()[0]) == recordTypeAlert {
+		c.rawConn.RawInput.Bytes()[0] == 21 {
+		_ = c.rawConn.ReadRecord()
 		// return n, err // will be io.EOF on closeNotify
 	}
 
@@ -128,24 +77,6 @@ func (c *ReadWaitConn) Upstream() any {
 	return c.Conn
 }
 
-var tlsRegistry []func(conn net.Conn) (loaded bool, tlsReadRecord func() error, tlsHandlePostHandshakeMessage func() error)
-
-func init() {
-	tlsRegistry = append(tlsRegistry, func(conn net.Conn) (loaded bool, tlsReadRecord func() error, tlsHandlePostHandshakeMessage func() error) {
-		tlsConn, loaded := conn.(*tls.STDConn)
-		if !loaded {
-			return
-		}
-		return true, func() error {
-				return stdTLSReadRecord(tlsConn)
-			}, func() error {
-				return stdTLSHandlePostHandshakeMessage(tlsConn)
-			}
-	})
+func (c *ReadWaitConn) ReaderReplaceable() bool {
+	return true
 }
-
-//go:linkname stdTLSReadRecord crypto/tls.(*Conn).readRecord
-func stdTLSReadRecord(c *tls.STDConn) error
-
-//go:linkname stdTLSHandlePostHandshakeMessage crypto/tls.(*Conn).handlePostHandshakeMessage
-func stdTLSHandlePostHandshakeMessage(c *tls.STDConn) error

common/badtls/read_wait_stub.go

@@ -1,4 +1,4 @@
-//go:build !go1.21 || without_badtls
+//go:build !go1.25 || without_badtls
 
 package badtls
 

common/badtls/read_wait_utls.go

@@ -1,32 +0,0 @@
-//go:build go1.21 && !without_badtls && with_utls
-
-package badtls
-
-import (
-	"net"
-	_ "unsafe"
-
-	"github.com/sagernet/sing/common"
-
-	"github.com/metacubex/utls"
-)
-
-func init() {
-	tlsRegistry = append(tlsRegistry, func(conn net.Conn) (loaded bool, tlsReadRecord func() error, tlsHandlePostHandshakeMessage func() error) {
-		tlsConn, loaded := common.Cast[*tls.UConn](conn)
-		if !loaded {
-			return
-		}
-		return true, func() error {
-				return utlsReadRecord(tlsConn.Conn)
-			}, func() error {
-				return utlsHandlePostHandshakeMessage(tlsConn.Conn)
-			}
-	})
-}
-
-//go:linkname utlsReadRecord github.com/metacubex/utls.(*Conn).readRecord
-func utlsReadRecord(c *tls.Conn) error
-
-//go:linkname utlsHandlePostHandshakeMessage github.com/metacubex/utls.(*Conn).handlePostHandshakeMessage
-func utlsHandlePostHandshakeMessage(c *tls.Conn) error

common/badtls/registry.go

@@ -0,0 +1,62 @@
+//go:build go1.25 && !without_badtls
+
+package badtls
+
+import (
+	"crypto/tls"
+	"net"
+	"unsafe"
+)
+
+type Methods struct {
+	readRecord                 func(c unsafe.Pointer) error
+	handlePostHandshakeMessage func(c unsafe.Pointer) error
+	writeRecordLocked          func(c unsafe.Pointer, typ uint16, data []byte) (int, error)
+
+	setErrorLocked   func(hc unsafe.Pointer, err error) error
+	decrypt          func(hc unsafe.Pointer, record []byte) ([]byte, uint8, error)
+	setTrafficSecret func(hc unsafe.Pointer, suite unsafe.Pointer, level int, secret []byte)
+	explicitNonceLen func(hc unsafe.Pointer) int
+}
+
+var methodRegistry []func(conn net.Conn) (unsafe.Pointer, *Methods, bool)
+
+func init() {
+	methodRegistry = append(methodRegistry, func(conn net.Conn) (unsafe.Pointer, *Methods, bool) {
+		tlsConn, loaded := conn.(*tls.Conn)
+		if !loaded {
+			return nil, nil, false
+		}
+		return unsafe.Pointer(tlsConn), &Methods{
+			readRecord:                 stdTLSReadRecord,
+			handlePostHandshakeMessage: stdTLSHandlePostHandshakeMessage,
+			writeRecordLocked:          stdWriteRecordLocked,
+
+			setErrorLocked:   stdSetErrorLocked,
+			decrypt:          stdDecrypt,
+			setTrafficSecret: stdSetTrafficSecret,
+			explicitNonceLen: stdExplicitNonceLen,
+		}, true
+	})
+}
+
+//go:linkname stdTLSReadRecord crypto/tls.(*Conn).readRecord
+func stdTLSReadRecord(c unsafe.Pointer) error
+
+//go:linkname stdTLSHandlePostHandshakeMessage crypto/tls.(*Conn).handlePostHandshakeMessage
+func stdTLSHandlePostHandshakeMessage(c unsafe.Pointer) error
+
+//go:linkname stdWriteRecordLocked crypto/tls.(*Conn).writeRecordLocked
+func stdWriteRecordLocked(c unsafe.Pointer, typ uint16, data []byte) (int, error)
+
+//go:linkname stdSetErrorLocked crypto/tls.(*halfConn).setErrorLocked
+func stdSetErrorLocked(hc unsafe.Pointer, err error) error
+
+//go:linkname stdDecrypt crypto/tls.(*halfConn).decrypt
+func stdDecrypt(hc unsafe.Pointer, record []byte) ([]byte, uint8, error)
+
+//go:linkname stdSetTrafficSecret crypto/tls.(*halfConn).setTrafficSecret
+func stdSetTrafficSecret(hc unsafe.Pointer, suite unsafe.Pointer, level int, secret []byte)
+
+//go:linkname stdExplicitNonceLen crypto/tls.(*halfConn).explicitNonceLen
+func stdExplicitNonceLen(hc unsafe.Pointer) int

common/badtls/registry_utls.go

@@ -0,0 +1,56 @@
+//go:build go1.25 && !without_badtls
+
+package badtls
+
+import (
+	"net"
+	"unsafe"
+
+	N "github.com/sagernet/sing/common/network"
+
+	"github.com/metacubex/utls"
+)
+
+func init() {
+	methodRegistry = append(methodRegistry, func(conn net.Conn) (unsafe.Pointer, *Methods, bool) {
+		var pointer unsafe.Pointer
+		if uConn, loaded := N.CastReader[*tls.Conn](conn); loaded {
+			pointer = unsafe.Pointer(uConn)
+		} else if uConn, loaded := N.CastReader[*tls.UConn](conn); loaded {
+			pointer = unsafe.Pointer(uConn.Conn)
+		} else {
+			return nil, nil, false
+		}
+		return pointer, &Methods{
+			readRecord:                 utlsReadRecord,
+			handlePostHandshakeMessage: utlsHandlePostHandshakeMessage,
+			writeRecordLocked:          utlsWriteRecordLocked,
+
+			setErrorLocked:   utlsSetErrorLocked,
+			decrypt:          utlsDecrypt,
+			setTrafficSecret: utlsSetTrafficSecret,
+			explicitNonceLen: utlsExplicitNonceLen,
+		}, true
+	})
+}
+
+//go:linkname utlsReadRecord github.com/metacubex/utls.(*Conn).readRecord
+func utlsReadRecord(c unsafe.Pointer) error
+
+//go:linkname utlsHandlePostHandshakeMessage github.com/metacubex/utls.(*Conn).handlePostHandshakeMessage
+func utlsHandlePostHandshakeMessage(c unsafe.Pointer) error
+
+//go:linkname utlsWriteRecordLocked github.com/metacubex/utls.(*Conn).writeRecordLocked
+func utlsWriteRecordLocked(hc unsafe.Pointer, typ uint16, data []byte) (int, error)
+
+//go:linkname utlsSetErrorLocked github.com/metacubex/utls.(*halfConn).setErrorLocked
+func utlsSetErrorLocked(hc unsafe.Pointer, err error) error
+
+//go:linkname utlsDecrypt github.com/metacubex/utls.(*halfConn).decrypt
+func utlsDecrypt(hc unsafe.Pointer, record []byte) ([]byte, uint8, error)
+
+//go:linkname utlsSetTrafficSecret github.com/metacubex/utls.(*halfConn).setTrafficSecret
+func utlsSetTrafficSecret(hc unsafe.Pointer, suite unsafe.Pointer, level int, secret []byte)
+
+//go:linkname utlsExplicitNonceLen github.com/metacubex/utls.(*halfConn).explicitNonceLen
+func utlsExplicitNonceLen(hc unsafe.Pointer) int

common/badversion/version.go

@@ -5,6 +5,8 @@ import (
 	"strings"
 
 	F "github.com/sagernet/sing/common/format"
+
+	"golang.org/x/mod/semver"
 )
 
 type Version struct {
@@ -16,7 +18,19 @@ type Version struct {
 	PreReleaseVersion    int
 }
 
-func (v Version) After(anotherVersion Version) bool {
+func (v Version) LessThan(anotherVersion Version) bool {
+	return !v.GreaterThanOrEqual(anotherVersion)
+}
+
+func (v Version) LessThanOrEqual(anotherVersion Version) bool {
+	return v == anotherVersion || anotherVersion.GreaterThan(v)
+}
+
+func (v Version) GreaterThanOrEqual(anotherVersion Version) bool {
+	return v == anotherVersion || v.GreaterThan(anotherVersion)
+}
+
+func (v Version) GreaterThan(anotherVersion Version) bool {
 	if v.Major > anotherVersion.Major {
 		return true
 	} else if v.Major < anotherVersion.Major {
@@ -44,19 +58,29 @@ func (v Version) After(anotherVersion Version) bool {
 			} else if v.PreReleaseVersion < anotherVersion.PreReleaseVersion {
 				return false
 			}
-		} else if v.PreReleaseIdentifier == "rc" && anotherVersion.PreReleaseIdentifier == "beta" {
+		}
+		preReleaseIdentifier := parsePreReleaseIdentifier(v.PreReleaseIdentifier)
+		anotherPreReleaseIdentifier := parsePreReleaseIdentifier(anotherVersion.PreReleaseIdentifier)
+		if preReleaseIdentifier < anotherPreReleaseIdentifier {
 			return true
-		} else if v.PreReleaseIdentifier == "beta" && anotherVersion.PreReleaseIdentifier == "rc" {
-			return false
-		} else if v.PreReleaseIdentifier == "beta" && anotherVersion.PreReleaseIdentifier == "alpha" {
-			return true
-		} else if v.PreReleaseIdentifier == "alpha" && anotherVersion.PreReleaseIdentifier == "beta" {
+		} else if preReleaseIdentifier > anotherPreReleaseIdentifier {
 			return false
 		}
 	}
 	return false
 }
 
+func parsePreReleaseIdentifier(identifier string) int {
+	if strings.HasPrefix(identifier, "rc") {
+		return 1
+	} else if strings.HasPrefix(identifier, "beta") {
+		return 2
+	} else if strings.HasPrefix(identifier, "alpha") {
+		return 3
+	}
+	return 0
+}
+
 func (v Version) VersionString() string {
 	return F.ToString(v.Major, ".", v.Minor, ".", v.Patch)
 }
@@ -83,6 +107,10 @@ func (v Version) BadString() string {
 	return version
 }
 
+func IsValid(versionName string) bool {
+	return semver.IsValid("v" + versionName)
+}
+
 func Parse(versionName string) (version Version) {
 	if strings.HasPrefix(versionName, "v") {
 		versionName = versionName[1:]

common/badversion/version_test.go

@@ -10,9 +10,9 @@ func TestCompareVersion(t *testing.T) {
 	t.Parallel()
 	require.Equal(t, "1.3.0-beta.1", Parse("v1.3.0-beta1").String())
 	require.Equal(t, "1.3-beta1", Parse("v1.3.0-beta.1").BadString())
-	require.True(t, Parse("1.3.0").After(Parse("1.3-beta1")))
-	require.True(t, Parse("1.3.0").After(Parse("1.3.0-beta1")))
-	require.True(t, Parse("1.3.0-beta1").After(Parse("1.3.0-alpha1")))
-	require.True(t, Parse("1.3.1").After(Parse("1.3.0")))
-	require.True(t, Parse("1.4").After(Parse("1.3")))
+	require.True(t, Parse("1.3.0").GreaterThan(Parse("1.3-beta1")))
+	require.True(t, Parse("1.3.0").GreaterThan(Parse("1.3.0-beta1")))
+	require.True(t, Parse("1.3.0-beta1").GreaterThan(Parse("1.3.0-alpha1")))
+	require.True(t, Parse("1.3.1").GreaterThan(Parse("1.3.0")))
+	require.True(t, Parse("1.4").GreaterThan(Parse("1.3")))
 }

common/certificate/store.go

@@ -7,6 +7,7 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"sync"
 
 	"github.com/sagernet/fswatch"
 	"github.com/sagernet/sing-box/adapter"
@@ -21,6 +22,7 @@ import (
 var _ adapter.CertificateStore = (*Store)(nil)
 
 type Store struct {
+	access                    sync.RWMutex
 	systemPool                *x509.CertPool
 	currentPool               *x509.CertPool
 	certificate               string
@@ -115,10 +117,14 @@ func (s *Store) Close() error {
 }
 
 func (s *Store) Pool() *x509.CertPool {
+	s.access.RLock()
+	defer s.access.RUnlock()
 	return s.currentPool
 }
 
 func (s *Store) update() error {
+	s.access.Lock()
+	defer s.access.Unlock()
 	var currentPool *x509.CertPool
 	if s.systemPool == nil {
 		currentPool = x509.NewCertPool()

common/convertor/adguard/convertor.go

@@ -454,5 +454,5 @@ func parseADGuardIPCIDRLine(ruleLine string) (netip.Prefix, error) {
 	for len(ruleParts) < 4 {
 		ruleParts = append(ruleParts, 0)
 	}
-	return netip.PrefixFrom(netip.AddrFrom4(*(*[4]byte)(ruleParts)), bitLen), nil
+	return netip.PrefixFrom(netip.AddrFrom4([4]byte(ruleParts)), bitLen), nil
 }

common/dialer/default.go

@@ -15,7 +15,6 @@ import (
 	"github.com/sagernet/sing-box/experimental/libbox/platform"
 	"github.com/sagernet/sing-box/option"
 	"github.com/sagernet/sing/common"
-	"github.com/sagernet/sing/common/atomic"
 	"github.com/sagernet/sing/common/control"
 	E "github.com/sagernet/sing/common/exceptions"
 	M "github.com/sagernet/sing/common/metadata"
@@ -43,7 +42,7 @@ type DefaultDialer struct {
 	networkType            []C.InterfaceType
 	fallbackNetworkType    []C.InterfaceType
 	networkFallbackDelay   time.Duration
-	networkLastFallback    atomic.TypedValue[time.Time]
+	networkLastFallback    common.TypedValue[time.Time]
 }
 
 func NewDefault(ctx context.Context, options option.DialerOptions) (*DefaultDialer, error) {
@@ -89,37 +88,35 @@ func NewDefault(ctx context.Context, options option.DialerOptions) (*DefaultDial
 
 	if networkManager != nil {
 		defaultOptions := networkManager.DefaultOptions()
-		if !disableDefaultBind {
-			if defaultOptions.BindInterface != "" {
-				bindFunc := control.BindToInterface(networkManager.InterfaceFinder(), defaultOptions.BindInterface, -1)
+		if defaultOptions.BindInterface != "" {
+			bindFunc := control.BindToInterface(networkManager.InterfaceFinder(), defaultOptions.BindInterface, -1)
+			dialer.Control = control.Append(dialer.Control, bindFunc)
+			listener.Control = control.Append(listener.Control, bindFunc)
+		} else if networkManager.AutoDetectInterface() && !disableDefaultBind {
+			if platformInterface != nil {
+				networkStrategy = (*C.NetworkStrategy)(options.NetworkStrategy)
+				networkType = common.Map(options.NetworkType, option.InterfaceType.Build)
+				fallbackNetworkType = common.Map(options.FallbackNetworkType, option.InterfaceType.Build)
+				if networkStrategy == nil && len(networkType) == 0 && len(fallbackNetworkType) == 0 {
+					networkStrategy = defaultOptions.NetworkStrategy
+					networkType = defaultOptions.NetworkType
+					fallbackNetworkType = defaultOptions.FallbackNetworkType
+				}
+				networkFallbackDelay = time.Duration(options.FallbackDelay)
+				if networkFallbackDelay == 0 && defaultOptions.FallbackDelay != 0 {
+					networkFallbackDelay = defaultOptions.FallbackDelay
+				}
+				if networkStrategy == nil {
+					networkStrategy = common.Ptr(C.NetworkStrategyDefault)
+					defaultNetworkStrategy = true
+				}
+				bindFunc := networkManager.ProtectFunc()
+				dialer.Control = control.Append(dialer.Control, bindFunc)
+				listener.Control = control.Append(listener.Control, bindFunc)
+			} else {
+				bindFunc := networkManager.AutoDetectInterfaceFunc()
 				dialer.Control = control.Append(dialer.Control, bindFunc)
 				listener.Control = control.Append(listener.Control, bindFunc)
-			} else if networkManager.AutoDetectInterface() {
-				if platformInterface != nil {
-					networkStrategy = (*C.NetworkStrategy)(options.NetworkStrategy)
-					networkType = common.Map(options.NetworkType, option.InterfaceType.Build)
-					fallbackNetworkType = common.Map(options.FallbackNetworkType, option.InterfaceType.Build)
-					if networkStrategy == nil && len(networkType) == 0 && len(fallbackNetworkType) == 0 {
-						networkStrategy = defaultOptions.NetworkStrategy
-						networkType = defaultOptions.NetworkType
-						fallbackNetworkType = defaultOptions.FallbackNetworkType
-					}
-					networkFallbackDelay = time.Duration(options.FallbackDelay)
-					if networkFallbackDelay == 0 && defaultOptions.FallbackDelay != 0 {
-						networkFallbackDelay = defaultOptions.FallbackDelay
-					}
-					if networkStrategy == nil {
-						networkStrategy = common.Ptr(C.NetworkStrategyDefault)
-						defaultNetworkStrategy = true
-					}
-					bindFunc := networkManager.ProtectFunc()
-					dialer.Control = control.Append(dialer.Control, bindFunc)
-					listener.Control = control.Append(listener.Control, bindFunc)
-				} else {
-					bindFunc := networkManager.AutoDetectInterfaceFunc()
-					dialer.Control = control.Append(dialer.Control, bindFunc)
-					listener.Control = control.Append(listener.Control, bindFunc)
-				}
 			}
 		}
 		if options.RoutingMark == 0 && defaultOptions.RoutingMark != 0 {
@@ -127,6 +124,11 @@ func NewDefault(ctx context.Context, options option.DialerOptions) (*DefaultDial
 			listener.Control = control.Append(listener.Control, setMarkWrapper(networkManager, defaultOptions.RoutingMark, true))
 		}
 	}
+	if networkManager != nil {
+		markFunc := networkManager.AutoRedirectOutputMarkFunc()
+		dialer.Control = control.Append(dialer.Control, markFunc)
+		listener.Control = control.Append(listener.Control, markFunc)
+	}
 	if options.ReuseAddr {
 		listener.Control = control.Append(listener.Control, control.ReuseAddr())
 	}
@@ -271,7 +273,7 @@ func (d *DefaultDialer) DialParallelInterface(ctx context.Context, network strin
 	} else {
 		dialer = d.udpDialer4
 	}
-	fastFallback := time.Now().Sub(d.networkLastFallback.Load()) < C.TCPTimeout
+	fastFallback := time.Since(d.networkLastFallback.Load()) < C.TCPTimeout
 	var (
 		conn      net.Conn
 		isPrimary bool
@@ -313,6 +315,14 @@ func (d *DefaultDialer) ListenPacket(ctx context.Context, destination M.Socksadd
 	}
 }
 
+func (d *DefaultDialer) DialerForICMPDestination(destination netip.Addr) net.Dialer {
+	if !destination.Is6() {
+		return dialerFromTCPDialer(d.dialer6)
+	} else {
+		return dialerFromTCPDialer(d.dialer4)
+	}
+}
+
 func (d *DefaultDialer) ListenSerialInterfacePacket(ctx context.Context, destination M.Socksaddr, strategy *C.NetworkStrategy, interfaceType []C.InterfaceType, fallbackInterfaceType []C.InterfaceType, fallbackDelay time.Duration) (net.PacketConn, error) {
 	if strategy == nil {
 		strategy = d.networkStrategy
@@ -346,18 +356,8 @@ func (d *DefaultDialer) ListenSerialInterfacePacket(ctx context.Context, destina
 	return trackPacketConn(packetConn, nil)
 }
 
-func (d *DefaultDialer) ListenPacketCompat(network, address string) (net.PacketConn, error) {
-	udpListener := d.udpListener
-	udpListener.Control = control.Append(udpListener.Control, func(network, address string, conn syscall.RawConn) error {
-		for _, wgControlFn := range WgControlFns {
-			err := wgControlFn(network, address, conn)
-			if err != nil {
-				return err
-			}
-		}
-		return nil
-	})
-	return udpListener.ListenPacket(context.Background(), network, address)
+func (d *DefaultDialer) WireGuardControl() control.Func {
+	return d.udpListener.Control
 }
 
 func trackConn(conn net.Conn, err error) (net.Conn, error) {

common/dialer/dialer.go

@@ -89,7 +89,6 @@ func NewWithOptions(options Options) (N.Dialer, error) {
 			dnsQueryOptions = adapter.DNSQueryOptions{
 				Transport:    transport,
 				Strategy:     strategy,
-				Timeout:      time.Duration(dialOptions.DomainResolver.Timeout),
 				DisableCache: dialOptions.DomainResolver.DisableCache,
 				RewriteTTL:   dialOptions.DomainResolver.RewriteTTL,
 				ClientSubnet: dialOptions.DomainResolver.ClientSubnet.Build(netip.Prefix{}),
@@ -112,7 +111,7 @@ func NewWithOptions(options Options) (N.Dialer, error) {
 					dnsQueryOptions.Transport = dnsTransport.Default()
 				} else if options.NewDialer {
 					return nil, E.New("missing domain resolver for domain server address")
-				} else if !options.DirectOutbound {
+				} else {
 					deprecated.Report(options.Context, deprecated.OptionMissingDomainResolver)
 				}
 			}

common/dialer/tfo.go

@@ -8,8 +8,10 @@ import (
 	"net"
 	"os"
 	"sync"
+	"sync/atomic"
 	"time"
 
+	"github.com/sagernet/sing/common"
 	"github.com/sagernet/sing/common/bufio"
 	M "github.com/sagernet/sing/common/metadata"
 	N "github.com/sagernet/sing/common/network"
@@ -22,7 +24,7 @@ type slowOpenConn struct {
 	ctx         context.Context
 	network     string
 	destination M.Socksaddr
-	conn        net.Conn
+	conn        atomic.Pointer[net.TCPConn]
 	create      chan struct{}
 	done        chan struct{}
 	access      sync.Mutex
@@ -50,22 +52,25 @@ func DialSlowContext(dialer *tcpDialer, ctx context.Context, network string, des
 }
 
 func (c *slowOpenConn) Read(b []byte) (n int, err error) {
-	if c.conn == nil {
-		select {
-		case <-c.create:
-			if c.err != nil {
-				return 0, c.err
-			}
-		case <-c.done:
-			return 0, os.ErrClosed
-		}
+	conn := c.conn.Load()
+	if conn != nil {
+		return conn.Read(b)
+	}
+	select {
+	case <-c.create:
+		if c.err != nil {
+			return 0, c.err
+		}
+		return c.conn.Load().Read(b)
+	case <-c.done:
+		return 0, os.ErrClosed
 	}
-	return c.conn.Read(b)
 }
 
 func (c *slowOpenConn) Write(b []byte) (n int, err error) {
-	if c.conn != nil {
-		return c.conn.Write(b)
+	tcpConn := c.conn.Load()
+	if tcpConn != nil {
+		return tcpConn.Write(b)
 	}
 	c.access.Lock()
 	defer c.access.Unlock()
@@ -74,7 +79,7 @@ func (c *slowOpenConn) Write(b []byte) (n int, err error) {
 		if c.err != nil {
 			return 0, c.err
 		}
-		return c.conn.Write(b)
+		return c.conn.Load().Write(b)
 	case <-c.done:
 		return 0, os.ErrClosed
 	default:
@@ -83,7 +88,7 @@ func (c *slowOpenConn) Write(b []byte) (n int, err error) {
 	if err != nil {
 		c.err = err
 	} else {
-		c.conn = conn
+		c.conn.Store(conn.(*net.TCPConn))
 	}
 	n = len(b)
 	close(c.create)
@@ -93,70 +98,77 @@ func (c *slowOpenConn) Write(b []byte) (n int, err error) {
 func (c *slowOpenConn) Close() error {
 	c.closeOnce.Do(func() {
 		close(c.done)
-		if c.conn != nil {
-			c.conn.Close()
+		conn := c.conn.Load()
+		if conn != nil {
+			conn.Close()
 		}
 	})
 	return nil
 }
 
 func (c *slowOpenConn) LocalAddr() net.Addr {
-	if c.conn == nil {
+	conn := c.conn.Load()
+	if conn == nil {
 		return M.Socksaddr{}
 	}
-	return c.conn.LocalAddr()
+	return conn.LocalAddr()
 }
 
 func (c *slowOpenConn) RemoteAddr() net.Addr {
-	if c.conn == nil {
+	conn := c.conn.Load()
+	if conn == nil {
 		return M.Socksaddr{}
 	}
-	return c.conn.RemoteAddr()
+	return conn.RemoteAddr()
 }
 
 func (c *slowOpenConn) SetDeadline(t time.Time) error {
-	if c.conn == nil {
+	conn := c.conn.Load()
+	if conn == nil {
 		return os.ErrInvalid
 	}
-	return c.conn.SetDeadline(t)
+	return conn.SetDeadline(t)
 }
 
 func (c *slowOpenConn) SetReadDeadline(t time.Time) error {
-	if c.conn == nil {
+	conn := c.conn.Load()
+	if conn == nil {
 		return os.ErrInvalid
 	}
-	return c.conn.SetReadDeadline(t)
+	return conn.SetReadDeadline(t)
 }
 
 func (c *slowOpenConn) SetWriteDeadline(t time.Time) error {
-	if c.conn == nil {
+	conn := c.conn.Load()
+	if conn == nil {
 		return os.ErrInvalid
 	}
-	return c.conn.SetWriteDeadline(t)
+	return conn.SetWriteDeadline(t)
 }
 
 func (c *slowOpenConn) Upstream() any {
-	return c.conn
+	return common.PtrOrNil(c.conn.Load())
 }
 
 func (c *slowOpenConn) ReaderReplaceable() bool {
-	return c.conn != nil
+	return c.conn.Load() != nil
 }
 
 func (c *slowOpenConn) WriterReplaceable() bool {
-	return c.conn != nil
+	return c.conn.Load() != nil
 }
 
 func (c *slowOpenConn) LazyHeadroom() bool {
-	return c.conn == nil
+	return c.conn.Load() == nil
 }
 
 func (c *slowOpenConn) NeedHandshake() bool {
-	return c.conn == nil
+	return c.conn.Load() == nil
 }
 
 func (c *slowOpenConn) WriteTo(w io.Writer) (n int64, err error) {
-	if c.conn == nil {
+	conn := c.conn.Load()
+	if conn == nil {
 		select {
 		case <-c.create:
 			if c.err != nil {
@@ -166,5 +178,5 @@ func (c *slowOpenConn) WriteTo(w io.Writer) (n int64, err error) {
 			return 0, c.err
 		}
 	}
-	return bufio.Copy(w, c.conn)
+	return bufio.Copy(w, c.conn.Load())
 }

common/dialer/wireguard.go

@@ -1,13 +1,9 @@
 package dialer
 
 import (
-	"net"
-
 	"github.com/sagernet/sing/common/control"
 )
 
 type WireGuardListener interface {
-	ListenPacketCompat(network, address string) (net.PacketConn, error)
+	WireGuardControl() control.Func
 }
-
-var WgControlFns []control.Func

common/ktls/ktls.go

@@ -0,0 +1,133 @@
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import (
+	"bytes"
+	"context"
+	"crypto/tls"
+	"errors"
+	"io"
+	"net"
+	"os"
+	"syscall"
+
+	"github.com/sagernet/sing-box/common/badtls"
+	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
+	N "github.com/sagernet/sing/common/network"
+	aTLS "github.com/sagernet/sing/common/tls"
+
+	"golang.org/x/sys/unix"
+)
+
+type Conn struct {
+	aTLS.Conn
+	ctx             context.Context
+	logger          logger.ContextLogger
+	conn            net.Conn
+	rawConn         *badtls.RawConn
+	syscallConn     syscall.Conn
+	rawSyscallConn  syscall.RawConn
+	readWaitOptions N.ReadWaitOptions
+	kernelTx        bool
+	kernelRx        bool
+	pendingRxSplice bool
+}
+
+func NewConn(ctx context.Context, logger logger.ContextLogger, conn aTLS.Conn, txOffload, rxOffload bool) (aTLS.Conn, error) {
+	err := Load()
+	if err != nil {
+		return nil, err
+	}
+	syscallConn, isSyscallConn := N.CastReader[interface {
+		io.Reader
+		syscall.Conn
+	}](conn.NetConn())
+	if !isSyscallConn {
+		return nil, os.ErrInvalid
+	}
+	rawSyscallConn, err := syscallConn.SyscallConn()
+	if err != nil {
+		return nil, err
+	}
+	rawConn, err := badtls.NewRawConn(conn)
+	if err != nil {
+		return nil, err
+	}
+	if *rawConn.Vers != tls.VersionTLS13 {
+		return nil, os.ErrInvalid
+	}
+	for rawConn.RawInput.Len() > 0 {
+		err = rawConn.ReadRecord()
+		if err != nil {
+			return nil, err
+		}
+		for rawConn.Hand.Len() > 0 {
+			err = rawConn.HandlePostHandshakeMessage()
+			if err != nil {
+				return nil, E.Cause(err, "handle post-handshake messages")
+			}
+		}
+	}
+	kConn := &Conn{
+		Conn:           conn,
+		ctx:            ctx,
+		logger:         logger,
+		conn:           conn.NetConn(),
+		rawConn:        rawConn,
+		syscallConn:    syscallConn,
+		rawSyscallConn: rawSyscallConn,
+	}
+	err = kConn.setupKernel(txOffload, rxOffload)
+	if err != nil {
+		return nil, err
+	}
+	return kConn, nil
+}
+
+func (c *Conn) Upstream() any {
+	return c.Conn
+}
+
+func (c *Conn) SyscallConnForRead() syscall.RawConn {
+	if !c.kernelRx {
+		return nil
+	}
+	if !*c.rawConn.IsClient {
+		c.logger.WarnContext(c.ctx, "ktls: RX splice is unavailable on the server size, since it will cause an unknown failure")
+		return nil
+	}
+	c.logger.DebugContext(c.ctx, "ktls: RX splice requested")
+	return c.rawSyscallConn
+}
+
+func (c *Conn) HandleSyscallReadError(inputErr error) ([]byte, error) {
+	if errors.Is(inputErr, unix.EINVAL) {
+		c.pendingRxSplice = true
+		err := c.readRecord()
+		if err != nil {
+			return nil, E.Cause(err, "ktls: handle non-application-data record")
+		}
+		var input bytes.Buffer
+		if c.rawConn.Input.Len() > 0 {
+			_, err = c.rawConn.Input.WriteTo(&input)
+			if err != nil {
+				return nil, err
+			}
+		}
+		return input.Bytes(), nil
+	} else if errors.Is(inputErr, unix.EBADMSG) {
+		return nil, c.rawConn.In.SetErrorLocked(c.sendAlert(alertBadRecordMAC))
+	} else {
+		return nil, E.Cause(inputErr, "ktls: unexpected errno")
+	}
+}
+
+func (c *Conn) SyscallConnForWrite() syscall.RawConn {
+	if !c.kernelTx {
+		return nil
+	}
+	c.logger.DebugContext(c.ctx, "ktls: TX splice requested")
+	return c.rawSyscallConn
+}

common/ktls/ktls_alert.go

@@ -0,0 +1,80 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import (
+	"crypto/tls"
+	"net"
+)
+
+const (
+	// alert level
+	alertLevelWarning = 1
+	alertLevelError   = 2
+)
+
+const (
+	alertCloseNotify                  = 0
+	alertUnexpectedMessage            = 10
+	alertBadRecordMAC                 = 20
+	alertDecryptionFailed             = 21
+	alertRecordOverflow               = 22
+	alertDecompressionFailure         = 30
+	alertHandshakeFailure             = 40
+	alertBadCertificate               = 42
+	alertUnsupportedCertificate       = 43
+	alertCertificateRevoked           = 44
+	alertCertificateExpired           = 45
+	alertCertificateUnknown           = 46
+	alertIllegalParameter             = 47
+	alertUnknownCA                    = 48
+	alertAccessDenied                 = 49
+	alertDecodeError                  = 50
+	alertDecryptError                 = 51
+	alertExportRestriction            = 60
+	alertProtocolVersion              = 70
+	alertInsufficientSecurity         = 71
+	alertInternalError                = 80
+	alertInappropriateFallback        = 86
+	alertUserCanceled                 = 90
+	alertNoRenegotiation              = 100
+	alertMissingExtension             = 109
+	alertUnsupportedExtension         = 110
+	alertCertificateUnobtainable      = 111
+	alertUnrecognizedName             = 112
+	alertBadCertificateStatusResponse = 113
+	alertBadCertificateHashValue      = 114
+	alertUnknownPSKIdentity           = 115
+	alertCertificateRequired          = 116
+	alertNoApplicationProtocol        = 120
+	alertECHRequired                  = 121
+)
+
+func (c *Conn) sendAlertLocked(err uint8) error {
+	switch err {
+	case alertNoRenegotiation, alertCloseNotify:
+		c.rawConn.Tmp[0] = alertLevelWarning
+	default:
+		c.rawConn.Tmp[0] = alertLevelError
+	}
+	c.rawConn.Tmp[1] = byte(err)
+
+	_, writeErr := c.writeRecordLocked(recordTypeAlert, c.rawConn.Tmp[0:2])
+	if err == alertCloseNotify {
+		// closeNotify is a special case in that it isn't an error.
+		return writeErr
+	}
+
+	return c.rawConn.Out.SetErrorLocked(&net.OpError{Op: "local error", Err: tls.AlertError(err)})
+}
+
+// sendAlert sends a TLS alert message.
+func (c *Conn) sendAlert(err uint8) error {
+	c.rawConn.Out.Lock()
+	defer c.rawConn.Out.Unlock()
+	return c.sendAlertLocked(err)
+}

common/ktls/ktls_cipher_suites_linux.go

@@ -0,0 +1,326 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import (
+	"crypto/tls"
+	"unsafe"
+
+	"github.com/sagernet/sing-box/common/badtls"
+)
+
+type kernelCryptoCipherType uint16
+
+const (
+	TLS_CIPHER_AES_GCM_128              kernelCryptoCipherType = 51
+	TLS_CIPHER_AES_GCM_128_IV_SIZE      kernelCryptoCipherType = 8
+	TLS_CIPHER_AES_GCM_128_KEY_SIZE     kernelCryptoCipherType = 16
+	TLS_CIPHER_AES_GCM_128_SALT_SIZE    kernelCryptoCipherType = 4
+	TLS_CIPHER_AES_GCM_128_TAG_SIZE     kernelCryptoCipherType = 16
+	TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE kernelCryptoCipherType = 8
+
+	TLS_CIPHER_AES_GCM_256              kernelCryptoCipherType = 52
+	TLS_CIPHER_AES_GCM_256_IV_SIZE      kernelCryptoCipherType = 8
+	TLS_CIPHER_AES_GCM_256_KEY_SIZE     kernelCryptoCipherType = 32
+	TLS_CIPHER_AES_GCM_256_SALT_SIZE    kernelCryptoCipherType = 4
+	TLS_CIPHER_AES_GCM_256_TAG_SIZE     kernelCryptoCipherType = 16
+	TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE kernelCryptoCipherType = 8
+
+	TLS_CIPHER_AES_CCM_128              kernelCryptoCipherType = 53
+	TLS_CIPHER_AES_CCM_128_IV_SIZE      kernelCryptoCipherType = 8
+	TLS_CIPHER_AES_CCM_128_KEY_SIZE     kernelCryptoCipherType = 16
+	TLS_CIPHER_AES_CCM_128_SALT_SIZE    kernelCryptoCipherType = 4
+	TLS_CIPHER_AES_CCM_128_TAG_SIZE     kernelCryptoCipherType = 16
+	TLS_CIPHER_AES_CCM_128_REC_SEQ_SIZE kernelCryptoCipherType = 8
+
+	TLS_CIPHER_CHACHA20_POLY1305              kernelCryptoCipherType = 54
+	TLS_CIPHER_CHACHA20_POLY1305_IV_SIZE      kernelCryptoCipherType = 12
+	TLS_CIPHER_CHACHA20_POLY1305_KEY_SIZE     kernelCryptoCipherType = 32
+	TLS_CIPHER_CHACHA20_POLY1305_SALT_SIZE    kernelCryptoCipherType = 0
+	TLS_CIPHER_CHACHA20_POLY1305_TAG_SIZE     kernelCryptoCipherType = 16
+	TLS_CIPHER_CHACHA20_POLY1305_REC_SEQ_SIZE kernelCryptoCipherType = 8
+
+	// TLS_CIPHER_SM4_GCM              kernelCryptoCipherType = 55
+	// TLS_CIPHER_SM4_GCM_IV_SIZE      kernelCryptoCipherType = 8
+	// TLS_CIPHER_SM4_GCM_KEY_SIZE     kernelCryptoCipherType = 16
+	// TLS_CIPHER_SM4_GCM_SALT_SIZE    kernelCryptoCipherType = 4
+	// TLS_CIPHER_SM4_GCM_TAG_SIZE     kernelCryptoCipherType = 16
+	// TLS_CIPHER_SM4_GCM_REC_SEQ_SIZE kernelCryptoCipherType = 8
+
+	// TLS_CIPHER_SM4_CCM              kernelCryptoCipherType = 56
+	// TLS_CIPHER_SM4_CCM_IV_SIZE      kernelCryptoCipherType = 8
+	// TLS_CIPHER_SM4_CCM_KEY_SIZE     kernelCryptoCipherType = 16
+	// TLS_CIPHER_SM4_CCM_SALT_SIZE    kernelCryptoCipherType = 4
+	// TLS_CIPHER_SM4_CCM_TAG_SIZE     kernelCryptoCipherType = 16
+	// TLS_CIPHER_SM4_CCM_REC_SEQ_SIZE kernelCryptoCipherType = 8
+
+	TLS_CIPHER_ARIA_GCM_128              kernelCryptoCipherType = 57
+	TLS_CIPHER_ARIA_GCM_128_IV_SIZE      kernelCryptoCipherType = 8
+	TLS_CIPHER_ARIA_GCM_128_KEY_SIZE     kernelCryptoCipherType = 16
+	TLS_CIPHER_ARIA_GCM_128_SALT_SIZE    kernelCryptoCipherType = 4
+	TLS_CIPHER_ARIA_GCM_128_TAG_SIZE     kernelCryptoCipherType = 16
+	TLS_CIPHER_ARIA_GCM_128_REC_SEQ_SIZE kernelCryptoCipherType = 8
+
+	TLS_CIPHER_ARIA_GCM_256              kernelCryptoCipherType = 58
+	TLS_CIPHER_ARIA_GCM_256_IV_SIZE      kernelCryptoCipherType = 8
+	TLS_CIPHER_ARIA_GCM_256_KEY_SIZE     kernelCryptoCipherType = 32
+	TLS_CIPHER_ARIA_GCM_256_SALT_SIZE    kernelCryptoCipherType = 4
+	TLS_CIPHER_ARIA_GCM_256_TAG_SIZE     kernelCryptoCipherType = 16
+	TLS_CIPHER_ARIA_GCM_256_REC_SEQ_SIZE kernelCryptoCipherType = 8
+)
+
+type kernelCrypto interface {
+	String() string
+}
+
+type kernelCryptoInfo struct {
+	version     uint16
+	cipher_type kernelCryptoCipherType
+}
+
+var _ kernelCrypto = &kernelCryptoAES128GCM{}
+
+type kernelCryptoAES128GCM struct {
+	kernelCryptoInfo
+	iv      [TLS_CIPHER_AES_GCM_128_IV_SIZE]byte
+	key     [TLS_CIPHER_AES_GCM_128_KEY_SIZE]byte
+	salt    [TLS_CIPHER_AES_GCM_128_SALT_SIZE]byte
+	rec_seq [TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE]byte
+}
+
+func (crypto *kernelCryptoAES128GCM) String() string {
+	crypto.cipher_type = TLS_CIPHER_AES_GCM_128
+	return string((*[unsafe.Sizeof(*crypto)]byte)(unsafe.Pointer(crypto))[:])
+}
+
+var _ kernelCrypto = &kernelCryptoAES256GCM{}
+
+type kernelCryptoAES256GCM struct {
+	kernelCryptoInfo
+	iv      [TLS_CIPHER_AES_GCM_256_IV_SIZE]byte
+	key     [TLS_CIPHER_AES_GCM_256_KEY_SIZE]byte
+	salt    [TLS_CIPHER_AES_GCM_256_SALT_SIZE]byte
+	rec_seq [TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE]byte
+}
+
+func (crypto *kernelCryptoAES256GCM) String() string {
+	crypto.cipher_type = TLS_CIPHER_AES_GCM_256
+	return string((*[unsafe.Sizeof(*crypto)]byte)(unsafe.Pointer(crypto))[:])
+}
+
+var _ kernelCrypto = &kernelCryptoAES128CCM{}
+
+type kernelCryptoAES128CCM struct {
+	kernelCryptoInfo
+	iv      [TLS_CIPHER_AES_CCM_128_IV_SIZE]byte
+	key     [TLS_CIPHER_AES_CCM_128_KEY_SIZE]byte
+	salt    [TLS_CIPHER_AES_CCM_128_SALT_SIZE]byte
+	rec_seq [TLS_CIPHER_AES_CCM_128_REC_SEQ_SIZE]byte
+}
+
+func (crypto *kernelCryptoAES128CCM) String() string {
+	crypto.cipher_type = TLS_CIPHER_AES_CCM_128
+	return string((*[unsafe.Sizeof(*crypto)]byte)(unsafe.Pointer(crypto))[:])
+}
+
+var _ kernelCrypto = &kernelCryptoChacha20Poly1035{}
+
+type kernelCryptoChacha20Poly1035 struct {
+	kernelCryptoInfo
+	iv      [TLS_CIPHER_CHACHA20_POLY1305_IV_SIZE]byte
+	key     [TLS_CIPHER_CHACHA20_POLY1305_KEY_SIZE]byte
+	salt    [TLS_CIPHER_CHACHA20_POLY1305_SALT_SIZE]byte
+	rec_seq [TLS_CIPHER_CHACHA20_POLY1305_REC_SEQ_SIZE]byte
+}
+
+func (crypto *kernelCryptoChacha20Poly1035) String() string {
+	crypto.cipher_type = TLS_CIPHER_CHACHA20_POLY1305
+	return string((*[unsafe.Sizeof(*crypto)]byte)(unsafe.Pointer(crypto))[:])
+}
+
+// var _ kernelCrypto = &kernelCryptoSM4GCM{}
+
+// type kernelCryptoSM4GCM struct {
+// 	kernelCryptoInfo
+// 	iv      [TLS_CIPHER_SM4_GCM_IV_SIZE]byte
+// 	key     [TLS_CIPHER_SM4_GCM_KEY_SIZE]byte
+// 	salt    [TLS_CIPHER_SM4_GCM_SALT_SIZE]byte
+// 	rec_seq [TLS_CIPHER_SM4_GCM_REC_SEQ_SIZE]byte
+// }
+
+// func (crypto *kernelCryptoSM4GCM) String() string {
+// 	crypto.cipher_type = TLS_CIPHER_SM4_GCM
+// 	return string((*[unsafe.Sizeof(*crypto)]byte)(unsafe.Pointer(crypto))[:])
+// }
+
+// var _ kernelCrypto = &kernelCryptoSM4CCM{}
+
+// type kernelCryptoSM4CCM struct {
+// 	kernelCryptoInfo
+// 	iv      [TLS_CIPHER_SM4_CCM_IV_SIZE]byte
+// 	key     [TLS_CIPHER_SM4_CCM_KEY_SIZE]byte
+// 	salt    [TLS_CIPHER_SM4_CCM_SALT_SIZE]byte
+// 	rec_seq [TLS_CIPHER_SM4_CCM_REC_SEQ_SIZE]byte
+// }
+
+// func (crypto *kernelCryptoSM4CCM) String() string {
+// 	crypto.cipher_type = TLS_CIPHER_SM4_CCM
+// 	return string((*[unsafe.Sizeof(*crypto)]byte)(unsafe.Pointer(crypto))[:])
+// }
+
+var _ kernelCrypto = &kernelCryptoARIA128GCM{}
+
+type kernelCryptoARIA128GCM struct {
+	kernelCryptoInfo
+	iv      [TLS_CIPHER_ARIA_GCM_128_IV_SIZE]byte
+	key     [TLS_CIPHER_ARIA_GCM_128_KEY_SIZE]byte
+	salt    [TLS_CIPHER_ARIA_GCM_128_SALT_SIZE]byte
+	rec_seq [TLS_CIPHER_ARIA_GCM_128_REC_SEQ_SIZE]byte
+}
+
+func (crypto *kernelCryptoARIA128GCM) String() string {
+	crypto.cipher_type = TLS_CIPHER_ARIA_GCM_128
+	return string((*[unsafe.Sizeof(*crypto)]byte)(unsafe.Pointer(crypto))[:])
+}
+
+var _ kernelCrypto = &kernelCryptoARIA256GCM{}
+
+type kernelCryptoARIA256GCM struct {
+	kernelCryptoInfo
+	iv      [TLS_CIPHER_ARIA_GCM_256_IV_SIZE]byte
+	key     [TLS_CIPHER_ARIA_GCM_256_KEY_SIZE]byte
+	salt    [TLS_CIPHER_ARIA_GCM_256_SALT_SIZE]byte
+	rec_seq [TLS_CIPHER_ARIA_GCM_256_REC_SEQ_SIZE]byte
+}
+
+func (crypto *kernelCryptoARIA256GCM) String() string {
+	crypto.cipher_type = TLS_CIPHER_ARIA_GCM_256
+	return string((*[unsafe.Sizeof(*crypto)]byte)(unsafe.Pointer(crypto))[:])
+}
+
+func kernelCipher(kernel *Support, hc *badtls.RawHalfConn, cipherSuite uint16, isRX bool) kernelCrypto {
+	if !kernel.TLS {
+		return nil
+	}
+
+	switch *hc.Version {
+	case tls.VersionTLS12:
+		if isRX && !kernel.TLS_Version13_RX {
+			return nil
+		}
+
+	case tls.VersionTLS13:
+		if !kernel.TLS_Version13 {
+			return nil
+		}
+
+		if isRX && !kernel.TLS_Version13_RX {
+			return nil
+		}
+
+	default:
+		return nil
+	}
+
+	var key, iv []byte
+	if *hc.Version == tls.VersionTLS13 {
+		key, iv = trafficKey(cipherSuiteTLS13ByID(cipherSuite), *hc.TrafficSecret)
+		/*if isRX {
+			key, iv = trafficKey(cipherSuiteTLS13ByID(cipherSuite), keyLog.RemoteTrafficSecret)
+		} else {
+			key, iv = trafficKey(cipherSuiteTLS13ByID(cipherSuite), keyLog.TrafficSecret)
+		}*/
+	} else {
+		// csPtr := cipherSuiteByID(cipherSuite)
+		// keysFromMasterSecret(*hc.Version, csPtr, keyLog.Secret, keyLog.Random)
+		return nil
+	}
+
+	switch cipherSuite {
+	case tls.TLS_AES_128_GCM_SHA256, tls.TLS_RSA_WITH_AES_128_GCM_SHA256, tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256:
+		crypto := new(kernelCryptoAES128GCM)
+
+		crypto.version = *hc.Version
+		copy(crypto.key[:], key)
+		copy(crypto.iv[:], iv[4:])
+		copy(crypto.salt[:], iv[:4])
+		crypto.rec_seq = *hc.Seq
+
+		return crypto
+	case tls.TLS_AES_256_GCM_SHA384, tls.TLS_RSA_WITH_AES_256_GCM_SHA384, tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384:
+		if !kernel.TLS_AES_256_GCM {
+			return nil
+		}
+
+		crypto := new(kernelCryptoAES256GCM)
+
+		crypto.version = *hc.Version
+		copy(crypto.key[:], key)
+		copy(crypto.iv[:], iv[4:])
+		copy(crypto.salt[:], iv[:4])
+		crypto.rec_seq = *hc.Seq
+
+		return crypto
+	//case tls.TLS_AES_128_CCM_SHA256, tls.TLS_RSA_WITH_AES_128_CCM_SHA256, tls.TLS_ECDHE_ECDSA_WITH_AES_128_CCM_SHA256:
+	//	if !kernel.TLS_AES_128_CCM {
+	//		return nil
+	//	}
+	//
+	//	crypto := new(kernelCryptoAES128CCM)
+	//
+	//	crypto.version = *hc.Version
+	//	copy(crypto.key[:], key)
+	//	copy(crypto.iv[:], iv[4:])
+	//	copy(crypto.salt[:], iv[:4])
+	//	crypto.rec_seq = *hc.Seq
+	//
+	//	return crypto
+	case tls.TLS_CHACHA20_POLY1305_SHA256, tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256, tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256:
+		if !kernel.TLS_CHACHA20_POLY1305 {
+			return nil
+		}
+
+		crypto := new(kernelCryptoChacha20Poly1035)
+
+		crypto.version = *hc.Version
+		copy(crypto.key[:], key)
+		copy(crypto.iv[:], iv)
+		crypto.rec_seq = *hc.Seq
+
+		return crypto
+	//case tls.TLS_RSA_WITH_ARIA_128_GCM_SHA256, tls.TLS_ECDHE_RSA_WITH_ARIA_128_GCM_SHA256, tls.TLS_ECDHE_ECDSA_WITH_ARIA_128_GCM_SHA256:
+	//	if !kernel.TLS_ARIA_GCM {
+	//		return nil
+	//	}
+	//
+	//	crypto := new(kernelCryptoARIA128GCM)
+	//
+	//	crypto.version = *hc.Version
+	//	copy(crypto.key[:], key)
+	//	copy(crypto.iv[:], iv[4:])
+	//	copy(crypto.salt[:], iv[:4])
+	//	crypto.rec_seq = *hc.Seq
+	//
+	//	return crypto
+	//case tls.TLS_RSA_WITH_ARIA_256_GCM_SHA384, tls.TLS_ECDHE_RSA_WITH_ARIA_256_GCM_SHA384, tls.TLS_ECDHE_ECDSA_WITH_ARIA_256_GCM_SHA384:
+	//	if !kernel.TLS_ARIA_GCM {
+	//		return nil
+	//	}
+	//
+	//	crypto := new(kernelCryptoARIA256GCM)
+	//
+	//	crypto.version = *hc.Version
+	//	copy(crypto.key[:], key)
+	//	copy(crypto.iv[:], iv[4:])
+	//	copy(crypto.salt[:], iv[:4])
+	//	crypto.rec_seq = *hc.Seq
+	//
+	//	return crypto
+	default:
+		return nil
+	}
+}

common/ktls/ktls_close.go

@@ -0,0 +1,67 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import (
+	"fmt"
+	"net"
+	"time"
+)
+
+func (c *Conn) Close() error {
+	if !c.kernelTx {
+		return c.Conn.Close()
+	}
+
+	// Interlock with Conn.Write above.
+	var x int32
+	for {
+		x = c.rawConn.ActiveCall.Load()
+		if x&1 != 0 {
+			return net.ErrClosed
+		}
+		if c.rawConn.ActiveCall.CompareAndSwap(x, x|1) {
+			break
+		}
+	}
+	if x != 0 {
+		// io.Writer and io.Closer should not be used concurrently.
+		// If Close is called while a Write is currently in-flight,
+		// interpret that as a sign that this Close is really just
+		// being used to break the Write and/or clean up resources and
+		// avoid sending the alertCloseNotify, which may block
+		// waiting on handshakeMutex or the c.out mutex.
+		return c.conn.Close()
+	}
+
+	var alertErr error
+	if c.rawConn.IsHandshakeComplete.Load() {
+		if err := c.closeNotify(); err != nil {
+			alertErr = fmt.Errorf("tls: failed to send closeNotify alert (but connection was closed anyway): %w", err)
+		}
+	}
+
+	if err := c.conn.Close(); err != nil {
+		return err
+	}
+	return alertErr
+}
+
+func (c *Conn) closeNotify() error {
+	c.rawConn.Out.Lock()
+	defer c.rawConn.Out.Unlock()
+
+	if !*c.rawConn.CloseNotifySent {
+		// Set a Write Deadline to prevent possibly blocking forever.
+		c.SetWriteDeadline(time.Now().Add(time.Second * 5))
+		*c.rawConn.CloseNotifyErr = c.sendAlertLocked(alertCloseNotify)
+		*c.rawConn.CloseNotifySent = true
+		// Any subsequent writes will fail.
+		c.SetWriteDeadline(time.Now())
+	}
+	return *c.rawConn.CloseNotifyErr
+}

common/ktls/ktls_const.go

@@ -0,0 +1,24 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+const (
+	maxPlaintext               = 16384        // maximum plaintext payload length
+	maxCiphertext              = 16384 + 2048 // maximum ciphertext payload length
+	maxCiphertextTLS13         = 16384 + 256  // maximum ciphertext length in TLS 1.3
+	recordHeaderLen            = 5            // record header length
+	maxHandshake               = 65536        // maximum handshake we support (protocol max is 16 MB)
+	maxHandshakeCertificateMsg = 262144       // maximum certificate message size (256 KiB)
+	maxUselessRecords          = 16           // maximum number of consecutive non-advancing records
+)
+
+const (
+	recordTypeChangeCipherSpec = 20
+	recordTypeAlert            = 21
+	recordTypeHandshake        = 22
+	recordTypeApplicationData  = 23
+)

common/ktls/ktls_handshake_messages.go

@@ -0,0 +1,238 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import (
+	"fmt"
+
+	"golang.org/x/crypto/cryptobyte"
+)
+
+// The marshalingFunction type is an adapter to allow the use of ordinary
+// functions as cryptobyte.MarshalingValue.
+type marshalingFunction func(b *cryptobyte.Builder) error
+
+func (f marshalingFunction) Marshal(b *cryptobyte.Builder) error {
+	return f(b)
+}
+
+// addBytesWithLength appends a sequence of bytes to the cryptobyte.Builder. If
+// the length of the sequence is not the value specified, it produces an error.
+func addBytesWithLength(b *cryptobyte.Builder, v []byte, n int) {
+	b.AddValue(marshalingFunction(func(b *cryptobyte.Builder) error {
+		if len(v) != n {
+			return fmt.Errorf("invalid value length: expected %d, got %d", n, len(v))
+		}
+		b.AddBytes(v)
+		return nil
+	}))
+}
+
+// addUint64 appends a big-endian, 64-bit value to the cryptobyte.Builder.
+func addUint64(b *cryptobyte.Builder, v uint64) {
+	b.AddUint32(uint32(v >> 32))
+	b.AddUint32(uint32(v))
+}
+
+// readUint64 decodes a big-endian, 64-bit value into out and advances over it.
+// It reports whether the read was successful.
+func readUint64(s *cryptobyte.String, out *uint64) bool {
+	var hi, lo uint32
+	if !s.ReadUint32(&hi) || !s.ReadUint32(&lo) {
+		return false
+	}
+	*out = uint64(hi)<<32 | uint64(lo)
+	return true
+}
+
+// readUint8LengthPrefixed acts like s.ReadUint8LengthPrefixed, but targets a
+// []byte instead of a cryptobyte.String.
+func readUint8LengthPrefixed(s *cryptobyte.String, out *[]byte) bool {
+	return s.ReadUint8LengthPrefixed((*cryptobyte.String)(out))
+}
+
+// readUint16LengthPrefixed acts like s.ReadUint16LengthPrefixed, but targets a
+// []byte instead of a cryptobyte.String.
+func readUint16LengthPrefixed(s *cryptobyte.String, out *[]byte) bool {
+	return s.ReadUint16LengthPrefixed((*cryptobyte.String)(out))
+}
+
+// readUint24LengthPrefixed acts like s.ReadUint24LengthPrefixed, but targets a
+// []byte instead of a cryptobyte.String.
+func readUint24LengthPrefixed(s *cryptobyte.String, out *[]byte) bool {
+	return s.ReadUint24LengthPrefixed((*cryptobyte.String)(out))
+}
+
+type keyUpdateMsg struct {
+	updateRequested bool
+}
+
+func (m *keyUpdateMsg) marshal() ([]byte, error) {
+	var b cryptobyte.Builder
+	b.AddUint8(typeKeyUpdate)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		if m.updateRequested {
+			b.AddUint8(1)
+		} else {
+			b.AddUint8(0)
+		}
+	})
+
+	return b.Bytes()
+}
+
+func (m *keyUpdateMsg) unmarshal(data []byte) bool {
+	s := cryptobyte.String(data)
+
+	var updateRequested uint8
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint8(&updateRequested) || !s.Empty() {
+		return false
+	}
+	switch updateRequested {
+	case 0:
+		m.updateRequested = false
+	case 1:
+		m.updateRequested = true
+	default:
+		return false
+	}
+	return true
+}
+
+// TLS handshake message types.
+const (
+	typeHelloRequest          uint8 = 0
+	typeClientHello           uint8 = 1
+	typeServerHello           uint8 = 2
+	typeNewSessionTicket      uint8 = 4
+	typeEndOfEarlyData        uint8 = 5
+	typeEncryptedExtensions   uint8 = 8
+	typeCertificate           uint8 = 11
+	typeServerKeyExchange     uint8 = 12
+	typeCertificateRequest    uint8 = 13
+	typeServerHelloDone       uint8 = 14
+	typeCertificateVerify     uint8 = 15
+	typeClientKeyExchange     uint8 = 16
+	typeFinished              uint8 = 20
+	typeCertificateStatus     uint8 = 22
+	typeKeyUpdate             uint8 = 24
+	typeCompressedCertificate uint8 = 25
+	typeMessageHash           uint8 = 254 // synthetic message
+)
+
+// TLS compression types.
+const (
+	compressionNone uint8 = 0
+)
+
+// TLS extension numbers
+const (
+	extensionServerName              uint16 = 0
+	extensionStatusRequest           uint16 = 5
+	extensionSupportedCurves         uint16 = 10 // supported_groups in TLS 1.3, see RFC 8446, Section 4.2.7
+	extensionSupportedPoints         uint16 = 11
+	extensionSignatureAlgorithms     uint16 = 13
+	extensionALPN                    uint16 = 16
+	extensionSCT                     uint16 = 18
+	extensionPadding                 uint16 = 21
+	extensionExtendedMasterSecret    uint16 = 23
+	extensionCompressCertificate     uint16 = 27 // compress_certificate in TLS 1.3
+	extensionSessionTicket           uint16 = 35
+	extensionPreSharedKey            uint16 = 41
+	extensionEarlyData               uint16 = 42
+	extensionSupportedVersions       uint16 = 43
+	extensionCookie                  uint16 = 44
+	extensionPSKModes                uint16 = 45
+	extensionCertificateAuthorities  uint16 = 47
+	extensionSignatureAlgorithmsCert uint16 = 50
+	extensionKeyShare                uint16 = 51
+	extensionQUICTransportParameters uint16 = 57
+	extensionALPS                    uint16 = 17513
+	extensionRenegotiationInfo       uint16 = 0xff01
+	extensionECHOuterExtensions      uint16 = 0xfd00
+	extensionEncryptedClientHello    uint16 = 0xfe0d
+)
+
+type handshakeMessage interface {
+	marshal() ([]byte, error)
+	unmarshal([]byte) bool
+}
+type newSessionTicketMsgTLS13 struct {
+	lifetime     uint32
+	ageAdd       uint32
+	nonce        []byte
+	label        []byte
+	maxEarlyData uint32
+}
+
+func (m *newSessionTicketMsgTLS13) marshal() ([]byte, error) {
+	var b cryptobyte.Builder
+	b.AddUint8(typeNewSessionTicket)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint32(m.lifetime)
+		b.AddUint32(m.ageAdd)
+		b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.nonce)
+		})
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.label)
+		})
+
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			if m.maxEarlyData > 0 {
+				b.AddUint16(extensionEarlyData)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint32(m.maxEarlyData)
+				})
+			}
+		})
+	})
+
+	return b.Bytes()
+}
+
+func (m *newSessionTicketMsgTLS13) unmarshal(data []byte) bool {
+	*m = newSessionTicketMsgTLS13{}
+	s := cryptobyte.String(data)
+
+	var extensions cryptobyte.String
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint32(&m.lifetime) ||
+		!s.ReadUint32(&m.ageAdd) ||
+		!readUint8LengthPrefixed(&s, &m.nonce) ||
+		!readUint16LengthPrefixed(&s, &m.label) ||
+		!s.ReadUint16LengthPrefixed(&extensions) ||
+		!s.Empty() {
+		return false
+	}
+
+	for !extensions.Empty() {
+		var extension uint16
+		var extData cryptobyte.String
+		if !extensions.ReadUint16(&extension) ||
+			!extensions.ReadUint16LengthPrefixed(&extData) {
+			return false
+		}
+
+		switch extension {
+		case extensionEarlyData:
+			if !extData.ReadUint32(&m.maxEarlyData) {
+				return false
+			}
+		default:
+			// Ignore unknown extensions.
+			continue
+		}
+
+		if !extData.Empty() {
+			return false
+		}
+	}
+
+	return true
+}

common/ktls/ktls_key_update.go

@@ -0,0 +1,173 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import (
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+)
+
+// handlePostHandshakeMessage processes a handshake message arrived after the
+// handshake is complete. Up to TLS 1.2, it indicates the start of a renegotiation.
+func (c *Conn) handlePostHandshakeMessage() error {
+	if *c.rawConn.Vers != tls.VersionTLS13 {
+		return errors.New("ktls: kernel does not support TLS 1.2 renegotiation")
+	}
+
+	msg, err := c.readHandshake(nil)
+	if err != nil {
+		return err
+	}
+	//c.retryCount++
+	//if c.retryCount > maxUselessRecords {
+	//	c.sendAlert(alertUnexpectedMessage)
+	//	return c.in.setErrorLocked(errors.New("tls: too many non-advancing records"))
+	//}
+
+	switch msg := msg.(type) {
+	case *newSessionTicketMsgTLS13:
+		// return errors.New("ktls: received new session ticket")
+		return nil
+	case *keyUpdateMsg:
+		return c.handleKeyUpdate(msg)
+	}
+	// The QUIC layer is supposed to treat an unexpected post-handshake CertificateRequest
+	// as a QUIC-level PROTOCOL_VIOLATION error (RFC 9001, Section 4.4). Returning an
+	// unexpected_message alert here doesn't provide it with enough information to distinguish
+	// this condition from other unexpected messages. This is probably fine.
+	c.sendAlert(alertUnexpectedMessage)
+	return fmt.Errorf("tls: received unexpected handshake message of type %T", msg)
+}
+
+func (c *Conn) handleKeyUpdate(keyUpdate *keyUpdateMsg) error {
+	//if c.quic != nil {
+	//	c.sendAlert(alertUnexpectedMessage)
+	//	return c.in.setErrorLocked(errors.New("tls: received unexpected key update message"))
+	//}
+
+	cipherSuite := cipherSuiteTLS13ByID(*c.rawConn.CipherSuite)
+	if cipherSuite == nil {
+		return c.rawConn.In.SetErrorLocked(c.sendAlert(alertInternalError))
+	}
+
+	newSecret := nextTrafficSecret(cipherSuite, *c.rawConn.In.TrafficSecret)
+	c.rawConn.In.SetTrafficSecret(cipherSuite, 0 /*tls.QUICEncryptionLevelInitial*/, newSecret)
+
+	err := c.resetupRX()
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return c.rawConn.In.SetErrorLocked(fmt.Errorf("ktls: resetupRX failed: %w", err))
+	}
+
+	if keyUpdate.updateRequested {
+		c.rawConn.Out.Lock()
+		defer c.rawConn.Out.Unlock()
+
+		resetup, err := c.resetupTX()
+		if err != nil {
+			c.sendAlertLocked(alertInternalError)
+			return c.rawConn.Out.SetErrorLocked(fmt.Errorf("ktls: resetupTX failed: %w", err))
+		}
+
+		msg := &keyUpdateMsg{}
+		msgBytes, err := msg.marshal()
+		if err != nil {
+			return err
+		}
+		_, err = c.writeRecordLocked(recordTypeHandshake, msgBytes)
+		if err != nil {
+			// Surface the error at the next write.
+			c.rawConn.Out.SetErrorLocked(err)
+			return nil
+		}
+
+		newSecret := nextTrafficSecret(cipherSuite, *c.rawConn.Out.TrafficSecret)
+		c.rawConn.Out.SetTrafficSecret(cipherSuite, 0 /*QUICEncryptionLevelInitial*/, newSecret)
+
+		err = resetup()
+		if err != nil {
+			return c.rawConn.Out.SetErrorLocked(fmt.Errorf("ktls: resetupTX failed: %w", err))
+		}
+	}
+
+	return nil
+}
+
+func (c *Conn) readHandshakeBytes(n int) error {
+	//if c.quic != nil {
+	//	return c.quicReadHandshakeBytes(n)
+	//}
+	for c.rawConn.Hand.Len() < n {
+		if err := c.readRecord(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (c *Conn) readHandshake(transcript io.Writer) (any, error) {
+	if err := c.readHandshakeBytes(4); err != nil {
+		return nil, err
+	}
+	data := c.rawConn.Hand.Bytes()
+
+	maxHandshakeSize := maxHandshake
+	// hasVers indicates we're past the first message, forcing someone trying to
+	// make us just allocate a large buffer to at least do the initial part of
+	// the handshake first.
+	//if c.haveVers && data[0] == typeCertificate {
+	// Since certificate messages are likely to be the only messages that
+	// can be larger than maxHandshake, we use a special limit for just
+	// those messages.
+	//maxHandshakeSize = maxHandshakeCertificateMsg
+	//}
+
+	n := int(data[1])<<16 | int(data[2])<<8 | int(data[3])
+	if n > maxHandshakeSize {
+		c.sendAlertLocked(alertInternalError)
+		return nil, c.rawConn.In.SetErrorLocked(fmt.Errorf("tls: handshake message of length %d bytes exceeds maximum of %d bytes", n, maxHandshakeSize))
+	}
+	if err := c.readHandshakeBytes(4 + n); err != nil {
+		return nil, err
+	}
+	data = c.rawConn.Hand.Next(4 + n)
+	return c.unmarshalHandshakeMessage(data, transcript)
+}
+
+func (c *Conn) unmarshalHandshakeMessage(data []byte, transcript io.Writer) (any, error) {
+	var m handshakeMessage
+	switch data[0] {
+	case typeNewSessionTicket:
+		if *c.rawConn.Vers == tls.VersionTLS13 {
+			m = new(newSessionTicketMsgTLS13)
+		} else {
+			return nil, os.ErrInvalid
+		}
+	case typeKeyUpdate:
+		m = new(keyUpdateMsg)
+	default:
+		return nil, c.rawConn.In.SetErrorLocked(c.sendAlert(alertUnexpectedMessage))
+	}
+
+	// The handshake message unmarshalers
+	// expect to be able to keep references to data,
+	// so pass in a fresh copy that won't be overwritten.
+	data = append([]byte(nil), data...)
+
+	if !m.unmarshal(data) {
+		return nil, c.rawConn.In.SetErrorLocked(c.sendAlert(alertDecodeError))
+	}
+
+	if transcript != nil {
+		transcript.Write(data)
+	}
+
+	return m, nil
+}

common/ktls/ktls_linux.go

@@ -0,0 +1,329 @@
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import (
+	"crypto/tls"
+	"errors"
+	"io"
+	"os"
+	"strings"
+	"sync"
+	"syscall"
+	"unsafe"
+
+	"github.com/sagernet/sing-box/common/badversion"
+	"github.com/sagernet/sing/common/control"
+	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/shell"
+
+	"golang.org/x/sys/unix"
+)
+
+// mod from https://gitlab.com/go-extension/tls
+
+const (
+	TLS_TX               = 1
+	TLS_RX               = 2
+	TLS_TX_ZEROCOPY_RO   = 3 // TX zerocopy (only sendfile now)
+	TLS_RX_EXPECT_NO_PAD = 4 // Attempt opportunistic zero-copy, TLS 1.3 only
+
+	TLS_SET_RECORD_TYPE = 1
+	TLS_GET_RECORD_TYPE = 2
+)
+
+type Support struct {
+	TLS, TLS_RX                     bool
+	TLS_Version13, TLS_Version13_RX bool
+
+	TLS_TX_ZEROCOPY  bool
+	TLS_RX_NOPADDING bool
+
+	TLS_AES_256_GCM       bool
+	TLS_AES_128_CCM       bool
+	TLS_CHACHA20_POLY1305 bool
+	TLS_SM4               bool
+	TLS_ARIA_GCM          bool
+
+	TLS_Version13_KeyUpdate bool
+}
+
+var KernelSupport = sync.OnceValues(func() (*Support, error) {
+	var uname unix.Utsname
+	err := unix.Uname(&uname)
+	if err != nil {
+		return nil, err
+	}
+
+	kernelVersion := badversion.Parse(strings.Trim(string(uname.Release[:]), "\x00"))
+	if err != nil {
+		return nil, err
+	}
+	var support Support
+	switch {
+	case kernelVersion.GreaterThanOrEqual(badversion.Version{Major: 6, Minor: 14}):
+		support.TLS_Version13_KeyUpdate = true
+		fallthrough
+	case kernelVersion.GreaterThanOrEqual(badversion.Version{Major: 6, Minor: 1}):
+		support.TLS_ARIA_GCM = true
+		fallthrough
+	case kernelVersion.GreaterThanOrEqual(badversion.Version{Major: 6}):
+		support.TLS_Version13_RX = true
+		support.TLS_RX_NOPADDING = true
+		fallthrough
+	case kernelVersion.GreaterThanOrEqual(badversion.Version{Major: 5, Minor: 19}):
+		support.TLS_TX_ZEROCOPY = true
+		fallthrough
+	case kernelVersion.GreaterThanOrEqual(badversion.Version{Major: 5, Minor: 16}):
+		support.TLS_SM4 = true
+		fallthrough
+	case kernelVersion.GreaterThanOrEqual(badversion.Version{Major: 5, Minor: 11}):
+		support.TLS_CHACHA20_POLY1305 = true
+		fallthrough
+	case kernelVersion.GreaterThanOrEqual(badversion.Version{Major: 5, Minor: 2}):
+		support.TLS_AES_128_CCM = true
+		fallthrough
+	case kernelVersion.GreaterThanOrEqual(badversion.Version{Major: 5, Minor: 1}):
+		support.TLS_AES_256_GCM = true
+		support.TLS_Version13 = true
+		fallthrough
+	case kernelVersion.GreaterThanOrEqual(badversion.Version{Major: 4, Minor: 17}):
+		support.TLS_RX = true
+		fallthrough
+	case kernelVersion.GreaterThanOrEqual(badversion.Version{Major: 4, Minor: 13}):
+		support.TLS = true
+	}
+
+	if support.TLS && support.TLS_Version13 {
+		_, err := os.Stat("/sys/module/tls")
+		if err != nil {
+			if os.Getuid() == 0 {
+				output, err := shell.Exec("modprobe", "tls").Read()
+				if err != nil {
+					return nil, E.Extend(E.Cause(err, "modprobe tls"), output)
+				}
+			} else {
+				return nil, E.New("ktls: kernel TLS module not loaded")
+			}
+		}
+	}
+
+	return &support, nil
+})
+
+func Load() error {
+	support, err := KernelSupport()
+	if err != nil {
+		return E.Cause(err, "ktls: check availability")
+	}
+	if !support.TLS || !support.TLS_Version13 {
+		return E.New("ktls: kernel does not support TLS 1.3")
+	}
+	return nil
+}
+
+func (c *Conn) setupKernel(txOffload, rxOffload bool) error {
+	if !txOffload && !rxOffload {
+		return os.ErrInvalid
+	}
+	support, err := KernelSupport()
+	if err != nil {
+		return E.Cause(err, "check availability")
+	}
+	if !support.TLS || !support.TLS_Version13 {
+		return E.New("kernel does not support TLS 1.3")
+	}
+	c.rawConn.Out.Lock()
+	defer c.rawConn.Out.Unlock()
+	err = control.Raw(c.rawSyscallConn, func(fd uintptr) error {
+		return syscall.SetsockoptString(int(fd), unix.SOL_TCP, unix.TCP_ULP, "tls")
+	})
+	if err != nil {
+		return os.NewSyscallError("setsockopt", err)
+	}
+
+	if txOffload {
+		txCrypto := kernelCipher(support, c.rawConn.Out, *c.rawConn.CipherSuite, false)
+		if txCrypto == nil {
+			return E.New("unsupported cipher suite")
+		}
+		err = control.Raw(c.rawSyscallConn, func(fd uintptr) error {
+			return syscall.SetsockoptString(int(fd), unix.SOL_TLS, TLS_TX, txCrypto.String())
+		})
+		if err != nil {
+			return err
+		}
+		if support.TLS_TX_ZEROCOPY {
+			err = control.Raw(c.rawSyscallConn, func(fd uintptr) error {
+				return syscall.SetsockoptInt(int(fd), unix.SOL_TLS, TLS_TX_ZEROCOPY_RO, 1)
+			})
+			if err != nil {
+				return err
+			}
+		}
+		c.kernelTx = true
+		c.logger.DebugContext(c.ctx, "ktls: kernel TLS TX enabled")
+	}
+
+	if rxOffload {
+		rxCrypto := kernelCipher(support, c.rawConn.In, *c.rawConn.CipherSuite, true)
+		if rxCrypto == nil {
+			return E.New("unsupported cipher suite")
+		}
+		err = control.Raw(c.rawSyscallConn, func(fd uintptr) error {
+			return syscall.SetsockoptString(int(fd), unix.SOL_TLS, TLS_RX, rxCrypto.String())
+		})
+		if err != nil {
+			return err
+		}
+		if *c.rawConn.Vers >= tls.VersionTLS13 && support.TLS_RX_NOPADDING {
+			err = control.Raw(c.rawSyscallConn, func(fd uintptr) error {
+				return syscall.SetsockoptInt(int(fd), unix.SOL_TLS, TLS_RX_EXPECT_NO_PAD, 1)
+			})
+			if err != nil {
+				return err
+			}
+		}
+		c.kernelRx = true
+		c.logger.DebugContext(c.ctx, "ktls: kernel TLS RX enabled")
+	}
+	return nil
+}
+
+func (c *Conn) resetupTX() (func() error, error) {
+	if !c.kernelTx {
+		return nil, nil
+	}
+	support, err := KernelSupport()
+	if err != nil {
+		return nil, err
+	}
+	if !support.TLS_Version13_KeyUpdate {
+		return nil, errors.New("ktls: kernel does not support rekey")
+	}
+	txCrypto := kernelCipher(support, c.rawConn.Out, *c.rawConn.CipherSuite, false)
+	if txCrypto == nil {
+		return nil, errors.New("ktls: set kernelCipher on unsupported tls session")
+	}
+	return func() error {
+		return control.Raw(c.rawSyscallConn, func(fd uintptr) error {
+			return syscall.SetsockoptString(int(fd), unix.SOL_TLS, TLS_TX, txCrypto.String())
+		})
+	}, nil
+}
+
+func (c *Conn) resetupRX() error {
+	if !c.kernelRx {
+		return nil
+	}
+	support, err := KernelSupport()
+	if err != nil {
+		return err
+	}
+	if !support.TLS_Version13_KeyUpdate {
+		return errors.New("ktls: kernel does not support rekey")
+	}
+	rxCrypto := kernelCipher(support, c.rawConn.In, *c.rawConn.CipherSuite, true)
+	if rxCrypto == nil {
+		return errors.New("ktls: set kernelCipher on unsupported tls session")
+	}
+	return control.Raw(c.rawSyscallConn, func(fd uintptr) error {
+		return syscall.SetsockoptString(int(fd), unix.SOL_TLS, TLS_RX, rxCrypto.String())
+	})
+}
+
+func (c *Conn) readKernelRecord() (uint8, []byte, error) {
+	if c.rawConn.RawInput.Len() < maxPlaintext {
+		c.rawConn.RawInput.Grow(maxPlaintext - c.rawConn.RawInput.Len())
+	}
+
+	data := c.rawConn.RawInput.Bytes()[:maxPlaintext]
+
+	// cmsg for record type
+	buffer := make([]byte, unix.CmsgSpace(1))
+	cmsg := (*unix.Cmsghdr)(unsafe.Pointer(&buffer[0]))
+	cmsg.SetLen(unix.CmsgLen(1))
+
+	var iov unix.Iovec
+	iov.Base = &data[0]
+	iov.SetLen(len(data))
+
+	var msg unix.Msghdr
+	msg.Control = &buffer[0]
+	msg.Controllen = cmsg.Len
+	msg.Iov = &iov
+	msg.Iovlen = 1
+
+	var n int
+	var err error
+	er := c.rawSyscallConn.Read(func(fd uintptr) bool {
+		n, err = recvmsg(int(fd), &msg, 0)
+		return err != unix.EAGAIN || c.pendingRxSplice
+	})
+	if er != nil {
+		return 0, nil, er
+	}
+	switch err {
+	case nil:
+	case syscall.EINVAL, syscall.EAGAIN:
+		return 0, nil, c.rawConn.In.SetErrorLocked(c.sendAlert(alertProtocolVersion))
+	case syscall.EMSGSIZE:
+		return 0, nil, c.rawConn.In.SetErrorLocked(c.sendAlert(alertRecordOverflow))
+	case syscall.EBADMSG:
+		return 0, nil, c.rawConn.In.SetErrorLocked(c.sendAlert(alertDecryptError))
+	default:
+		return 0, nil, err
+	}
+
+	if n <= 0 {
+		return 0, nil, c.rawConn.In.SetErrorLocked(io.EOF)
+	}
+
+	if cmsg.Level == unix.SOL_TLS && cmsg.Type == TLS_GET_RECORD_TYPE {
+		typ := buffer[unix.CmsgLen(0)]
+		return typ, data[:n], nil
+	}
+
+	return recordTypeApplicationData, data[:n], nil
+}
+
+func (c *Conn) writeKernelRecord(typ uint16, data []byte) (int, error) {
+	if typ == recordTypeApplicationData {
+		return c.conn.Write(data)
+	}
+
+	// cmsg for record type
+	buffer := make([]byte, unix.CmsgSpace(1))
+	cmsg := (*unix.Cmsghdr)(unsafe.Pointer(&buffer[0]))
+	cmsg.SetLen(unix.CmsgLen(1))
+	buffer[unix.CmsgLen(0)] = byte(typ)
+	cmsg.Level = unix.SOL_TLS
+	cmsg.Type = TLS_SET_RECORD_TYPE
+
+	var iov unix.Iovec
+	iov.Base = &data[0]
+	iov.SetLen(len(data))
+
+	var msg unix.Msghdr
+	msg.Control = &buffer[0]
+	msg.Controllen = cmsg.Len
+	msg.Iov = &iov
+	msg.Iovlen = 1
+
+	var n int
+	var err error
+	ew := c.rawSyscallConn.Write(func(fd uintptr) bool {
+		n, err = sendmsg(int(fd), &msg, 0)
+		return err != unix.EAGAIN
+	})
+	if ew != nil {
+		return 0, ew
+	}
+	return n, err
+}
+
+//go:linkname recvmsg golang.org/x/sys/unix.recvmsg
+func recvmsg(fd int, msg *unix.Msghdr, flags int) (n int, err error)
+
+//go:linkname sendmsg golang.org/x/sys/unix.sendmsg
+func sendmsg(fd int, msg *unix.Msghdr, flags int) (n int, err error)

common/ktls/ktls_prf.go

@@ -0,0 +1,24 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import "unsafe"
+
+//go:linkname cipherSuiteByID github.com/metacubex/utls.cipherSuiteByID
+func cipherSuiteByID(id uint16) unsafe.Pointer
+
+//go:linkname keysFromMasterSecret github.com/metacubex/utls.keysFromMasterSecret
+func keysFromMasterSecret(version uint16, suite unsafe.Pointer, masterSecret, clientRandom, serverRandom []byte, macLen, keyLen, ivLen int) (clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV []byte)
+
+//go:linkname cipherSuiteTLS13ByID github.com/metacubex/utls.cipherSuiteTLS13ByID
+func cipherSuiteTLS13ByID(id uint16) unsafe.Pointer
+
+//go:linkname nextTrafficSecret github.com/metacubex/utls.(*cipherSuiteTLS13).nextTrafficSecret
+func nextTrafficSecret(cs unsafe.Pointer, trafficSecret []byte) []byte
+
+//go:linkname trafficKey github.com/metacubex/utls.(*cipherSuiteTLS13).trafficKey
+func trafficKey(cs unsafe.Pointer, trafficSecret []byte) (key, iv []byte)

common/ktls/ktls_read.go

@@ -0,0 +1,292 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import (
+	"bytes"
+	"crypto/tls"
+	"fmt"
+	"io"
+	"net"
+)
+
+func (c *Conn) Read(b []byte) (int, error) {
+	if !c.kernelRx {
+		return c.Conn.Read(b)
+	}
+
+	if len(b) == 0 {
+		// Put this after Handshake, in case people were calling
+		// Read(nil) for the side effect of the Handshake.
+		return 0, nil
+	}
+
+	c.rawConn.In.Lock()
+	defer c.rawConn.In.Unlock()
+
+	for c.rawConn.Input.Len() == 0 {
+		if err := c.readRecord(); err != nil {
+			return 0, err
+		}
+		for c.rawConn.Hand.Len() > 0 {
+			if err := c.handlePostHandshakeMessage(); err != nil {
+				return 0, err
+			}
+		}
+	}
+
+	n, _ := c.rawConn.Input.Read(b)
+
+	// If a close-notify alert is waiting, read it so that we can return (n,
+	// EOF) instead of (n, nil), to signal to the HTTP response reading
+	// goroutine that the connection is now closed. This eliminates a race
+	// where the HTTP response reading goroutine would otherwise not observe
+	// the EOF until its next read, by which time a client goroutine might
+	// have already tried to reuse the HTTP connection for a new request.
+	// See https://golang.org/cl/76400046 and https://golang.org/issue/3514
+	if n != 0 && c.rawConn.Input.Len() == 0 && c.rawConn.RawInput.Len() > 0 &&
+		c.rawConn.RawInput.Bytes()[0] == recordTypeAlert {
+		if err := c.readRecord(); err != nil {
+			return n, err // will be io.EOF on closeNotify
+		}
+	}
+
+	return n, nil
+}
+
+func (c *Conn) readRecord() error {
+	if *c.rawConn.In.Err != nil {
+		return *c.rawConn.In.Err
+	}
+
+	typ, data, err := c.readRawRecord()
+	if err != nil {
+		return err
+	}
+
+	if len(data) > maxPlaintext {
+		return c.rawConn.In.SetErrorLocked(c.sendAlert(alertRecordOverflow))
+	}
+
+	// Application Data messages are always protected.
+	if c.rawConn.In.Cipher == nil && typ == recordTypeApplicationData {
+		return c.rawConn.In.SetErrorLocked(c.sendAlert(alertUnexpectedMessage))
+	}
+
+	//if typ != recordTypeAlert && typ != recordTypeChangeCipherSpec && len(data) > 0 {
+	// This is a state-advancing message: reset the retry count.
+	// c.retryCount = 0
+	//}
+
+	// Handshake messages MUST NOT be interleaved with other record types in TLS 1.3.
+	if *c.rawConn.Vers == tls.VersionTLS13 && typ != recordTypeHandshake && c.rawConn.Hand.Len() > 0 {
+		return c.rawConn.In.SetErrorLocked(c.sendAlert(alertUnexpectedMessage))
+	}
+
+	switch typ {
+	default:
+		return c.rawConn.In.SetErrorLocked(c.sendAlert(alertUnexpectedMessage))
+	case recordTypeAlert:
+		//if c.quic != nil {
+		//	return c.rawConn.In.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		//}
+		if len(data) != 2 {
+			return c.rawConn.In.SetErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		}
+		if data[1] == alertCloseNotify {
+			return c.rawConn.In.SetErrorLocked(io.EOF)
+		}
+		if *c.rawConn.Vers == tls.VersionTLS13 {
+			// TLS 1.3 removed warning-level alerts except for alertUserCanceled
+			// (RFC 8446, § 6.1). Since at least one major implementation
+			// (https://bugs.openjdk.org/browse/JDK-8323517) misuses this alert,
+			// many TLS stacks now ignore it outright when seen in a TLS 1.3
+			// handshake (e.g. BoringSSL, NSS, Rustls).
+			if data[1] == alertUserCanceled {
+				// Like TLS 1.2 alertLevelWarning alerts, we drop the record and retry.
+				return c.retryReadRecord( /*expectChangeCipherSpec*/ )
+			}
+			return c.rawConn.In.SetErrorLocked(&net.OpError{Op: "remote error", Err: tls.AlertError(data[1])})
+		}
+		switch data[0] {
+		case alertLevelWarning:
+			// Drop the record on the floor and retry.
+			return c.retryReadRecord( /*expectChangeCipherSpec*/ )
+		case alertLevelError:
+			return c.rawConn.In.SetErrorLocked(&net.OpError{Op: "remote error", Err: tls.AlertError(data[1])})
+		default:
+			return c.rawConn.In.SetErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		}
+
+	case recordTypeChangeCipherSpec:
+		if len(data) != 1 || data[0] != 1 {
+			return c.rawConn.In.SetErrorLocked(c.sendAlert(alertDecodeError))
+		}
+		// Handshake messages are not allowed to fragment across the CCS.
+		if c.rawConn.Hand.Len() > 0 {
+			return c.rawConn.In.SetErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		}
+		// In TLS 1.3, change_cipher_spec records are ignored until the
+		// Finished. See RFC 8446, Appendix D.4. Note that according to Section
+		// 5, a server can send a ChangeCipherSpec before its ServerHello, when
+		// c.vers is still unset. That's not useful though and suspicious if the
+		// server then selects a lower protocol version, so don't allow that.
+		if *c.rawConn.Vers == tls.VersionTLS13 {
+			return c.retryReadRecord( /*expectChangeCipherSpec*/ )
+		}
+		// if !expectChangeCipherSpec {
+		return c.rawConn.In.SetErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		//}
+		//if err := c.rawConn.In.changeCipherSpec(); err != nil {
+		//	return c.rawConn.In.setErrorLocked(c.sendAlert(err.(alert)))
+		//}
+
+	case recordTypeApplicationData:
+		// Some OpenSSL servers send empty records in order to randomize the
+		// CBC RawIV. Ignore a limited number of empty records.
+		if len(data) == 0 {
+			return c.retryReadRecord( /*expectChangeCipherSpec*/ )
+		}
+		// Note that data is owned by c.rawInput, following the Next call above,
+		// to avoid copying the plaintext. This is safe because c.rawInput is
+		// not read from or written to until c.input is drained.
+		c.rawConn.Input.Reset(data)
+	case recordTypeHandshake:
+		if len(data) == 0 {
+			return c.rawConn.In.SetErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		}
+		c.rawConn.Hand.Write(data)
+	}
+
+	return nil
+}
+
+//nolint:staticcheck
+func (c *Conn) readRawRecord() (typ uint8, data []byte, err error) {
+	// Read from kernel.
+	if c.kernelRx {
+		return c.readKernelRecord()
+	}
+
+	// Read header, payload.
+	if err = c.readFromUntil(c.conn, recordHeaderLen); err != nil {
+		// RFC 8446, Section 6.1 suggests that EOF without an alertCloseNotify
+		// is an error, but popular web sites seem to do this, so we accept it
+		// if and only if at the record boundary.
+		if err == io.ErrUnexpectedEOF && c.rawConn.RawInput.Len() == 0 {
+			err = io.EOF
+		}
+		if e, ok := err.(net.Error); !ok || !e.Temporary() {
+			c.rawConn.In.SetErrorLocked(err)
+		}
+		return
+	}
+	hdr := c.rawConn.RawInput.Bytes()[:recordHeaderLen]
+	typ = hdr[0]
+
+	vers := uint16(hdr[1])<<8 | uint16(hdr[2])
+	expectedVers := *c.rawConn.Vers
+	if expectedVers == tls.VersionTLS13 {
+		// All TLS 1.3 records are expected to have 0x0303 (1.2) after
+		// the initial hello (RFC 8446 Section 5.1).
+		expectedVers = tls.VersionTLS12
+	}
+	n := int(hdr[3])<<8 | int(hdr[4])
+	if /*c.haveVers && */ vers != expectedVers {
+		c.sendAlert(alertProtocolVersion)
+		msg := fmt.Sprintf("received record with version %x when expecting version %x", vers, expectedVers)
+		err = c.rawConn.In.SetErrorLocked(c.newRecordHeaderError(nil, msg))
+		return
+	}
+	//if !c.haveVers {
+	//	// First message, be extra suspicious: this might not be a TLS
+	//	// client. Bail out before reading a full 'body', if possible.
+	//	// The current max version is 3.3 so if the version is >= 16.0,
+	//	// it's probably not real.
+	//	if (typ != recordTypeAlert && typ != recordTypeHandshake) || vers >= 0x1000 {
+	//		err = c.rawConn.In.SetErrorLocked(c.newRecordHeaderError(c.conn, "first record does not look like a TLS handshake"))
+	//		return
+	//	}
+	//}
+	if *c.rawConn.Vers == tls.VersionTLS13 && n > maxCiphertextTLS13 || n > maxCiphertext {
+		c.sendAlert(alertRecordOverflow)
+		msg := fmt.Sprintf("oversized record received with length %d", n)
+		err = c.rawConn.In.SetErrorLocked(c.newRecordHeaderError(nil, msg))
+		return
+	}
+	if err = c.readFromUntil(c.conn, recordHeaderLen+n); err != nil {
+		if e, ok := err.(net.Error); !ok || !e.Temporary() {
+			c.rawConn.In.SetErrorLocked(err)
+		}
+		return
+	}
+
+	// Process message.
+	record := c.rawConn.RawInput.Next(recordHeaderLen + n)
+	data, typ, err = c.rawConn.In.Decrypt(record)
+	if err != nil {
+		err = c.rawConn.In.SetErrorLocked(c.sendAlert(uint8(err.(tls.AlertError))))
+		return
+	}
+	return
+}
+
+// retryReadRecord recurs into readRecordOrCCS to drop a non-advancing record, like
+// a warning alert, empty application_data, or a change_cipher_spec in TLS 1.3.
+func (c *Conn) retryReadRecord( /*expectChangeCipherSpec bool*/ ) error {
+	//c.retryCount++
+	//if c.retryCount > maxUselessRecords {
+	//	c.sendAlert(alertUnexpectedMessage)
+	//	return c.in.setErrorLocked(errors.New("tls: too many ignored records"))
+	//}
+	return c.readRecord( /*expectChangeCipherSpec*/ )
+}
+
+// atLeastReader reads from R, stopping with EOF once at least N bytes have been
+// read. It is different from an io.LimitedReader in that it doesn't cut short
+// the last Read call, and in that it considers an early EOF an error.
+type atLeastReader struct {
+	R io.Reader
+	N int64
+}
+
+func (r *atLeastReader) Read(p []byte) (int, error) {
+	if r.N <= 0 {
+		return 0, io.EOF
+	}
+	n, err := r.R.Read(p)
+	r.N -= int64(n) // won't underflow unless len(p) >= n > 9223372036854775809
+	if r.N > 0 && err == io.EOF {
+		return n, io.ErrUnexpectedEOF
+	}
+	if r.N <= 0 && err == nil {
+		return n, io.EOF
+	}
+	return n, err
+}
+
+// readFromUntil reads from r into c.rawConn.RawInput until c.rawConn.RawInput contains
+// at least n bytes or else returns an error.
+func (c *Conn) readFromUntil(r io.Reader, n int) error {
+	if c.rawConn.RawInput.Len() >= n {
+		return nil
+	}
+	needs := n - c.rawConn.RawInput.Len()
+	// There might be extra input waiting on the wire. Make a best effort
+	// attempt to fetch it so that it can be used in (*Conn).Read to
+	// "predict" closeNotify alerts.
+	c.rawConn.RawInput.Grow(needs + bytes.MinRead)
+	_, err := c.rawConn.RawInput.ReadFrom(&atLeastReader{r, int64(needs)})
+	return err
+}
+
+func (c *Conn) newRecordHeaderError(conn net.Conn, msg string) (err tls.RecordHeaderError) {
+	err.Msg = msg
+	err.Conn = conn
+	copy(err.RecordHeader[:], c.rawConn.RawInput.Bytes())
+	return err
+}

common/ktls/ktls_read_wait.go

@@ -0,0 +1,41 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import (
+	"github.com/sagernet/sing/common/buf"
+	N "github.com/sagernet/sing/common/network"
+)
+
+func (c *Conn) InitializeReadWaiter(options N.ReadWaitOptions) (needCopy bool) {
+	c.readWaitOptions = options
+	return false
+}
+
+func (c *Conn) WaitReadBuffer() (buffer *buf.Buffer, err error) {
+	c.rawConn.In.Lock()
+	defer c.rawConn.In.Unlock()
+	for c.rawConn.Input.Len() == 0 {
+		err = c.readRecord()
+		if err != nil {
+			return
+		}
+	}
+	buffer = c.readWaitOptions.NewBuffer()
+	n, err := c.rawConn.Input.Read(buffer.FreeBytes())
+	if err != nil {
+		buffer.Release()
+		return
+	}
+	buffer.Truncate(n)
+	if n != 0 && c.rawConn.Input.Len() == 0 && c.rawConn.Input.Len() > 0 &&
+		c.rawConn.RawInput.Bytes()[0] == recordTypeAlert {
+		_ = c.rawConn.ReadRecord()
+	}
+	c.readWaitOptions.PostReturn(buffer)
+	return
+}

common/ktls/ktls_stub.go

@@ -0,0 +1,15 @@
+//go:build !linux || !go1.25 || without_badtls
+
+package ktls
+
+import (
+	"context"
+	"os"
+
+	"github.com/sagernet/sing/common/logger"
+	aTLS "github.com/sagernet/sing/common/tls"
+)
+
+func NewConn(ctx context.Context, logger logger.ContextLogger, conn aTLS.Conn, txOffload, rxOffload bool) (aTLS.Conn, error) {
+	return nil, os.ErrInvalid
+}

common/ktls/ktls_write.go

@@ -0,0 +1,154 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && go1.25 && !without_badtls
+
+package ktls
+
+import (
+	"crypto/cipher"
+	"crypto/tls"
+	"errors"
+	"net"
+)
+
+func (c *Conn) Write(b []byte) (int, error) {
+	if !c.kernelTx {
+		return c.Conn.Write(b)
+	}
+	// interlock with Close below
+	for {
+		x := c.rawConn.ActiveCall.Load()
+		if x&1 != 0 {
+			return 0, net.ErrClosed
+		}
+		if c.rawConn.ActiveCall.CompareAndSwap(x, x+2) {
+			break
+		}
+	}
+	defer c.rawConn.ActiveCall.Add(-2)
+
+	//if err := c.Conn.HandshakeContext(context.Background()); err != nil {
+	//	return 0, err
+	//}
+
+	c.rawConn.Out.Lock()
+	defer c.rawConn.Out.Unlock()
+
+	if err := *c.rawConn.Out.Err; err != nil {
+		return 0, err
+	}
+
+	if !c.rawConn.IsHandshakeComplete.Load() {
+		return 0, tls.AlertError(alertInternalError)
+	}
+
+	if *c.rawConn.CloseNotifySent {
+		// return 0, errShutdown
+		return 0, errors.New("tls: protocol is shutdown")
+	}
+
+	// TLS 1.0 is susceptible to a chosen-plaintext
+	// attack when using block mode ciphers due to predictable IVs.
+	// This can be prevented by splitting each Application Data
+	// record into two records, effectively randomizing the RawIV.
+	//
+	// https://www.openssl.org/~bodo/tls-cbc.txt
+	// https://bugzilla.mozilla.org/show_bug.cgi?id=665814
+	// https://www.imperialviolet.org/2012/01/15/beastfollowup.html
+
+	var m int
+	if len(b) > 1 && *c.rawConn.Vers == tls.VersionTLS10 {
+		if _, ok := (*c.rawConn.Out.Cipher).(cipher.BlockMode); ok {
+			n, err := c.writeRecordLocked(recordTypeApplicationData, b[:1])
+			if err != nil {
+				return n, c.rawConn.Out.SetErrorLocked(err)
+			}
+			m, b = 1, b[1:]
+		}
+	}
+
+	n, err := c.writeRecordLocked(recordTypeApplicationData, b)
+	return n + m, c.rawConn.Out.SetErrorLocked(err)
+}
+
+func (c *Conn) writeRecordLocked(typ uint16, data []byte) (n int, err error) {
+	if !c.kernelTx {
+		return c.rawConn.WriteRecordLocked(typ, data)
+	}
+	/*for len(data) > 0 {
+		m := len(data)
+		if maxPayload := c.maxPayloadSizeForWrite(typ); m > maxPayload {
+			m = maxPayload
+		}
+		_, err = c.writeKernelRecord(typ, data[:m])
+		if err != nil {
+			return
+		}
+		n += m
+		data = data[m:]
+	}*/
+	return c.writeKernelRecord(typ, data)
+}
+
+const (
+	// tcpMSSEstimate is a conservative estimate of the TCP maximum segment
+	// size (MSS). A constant is used, rather than querying the kernel for
+	// the actual MSS, to avoid complexity. The value here is the IPv6
+	// minimum MTU (1280 bytes) minus the overhead of an IPv6 header (40
+	// bytes) and a TCP header with timestamps (32 bytes).
+	tcpMSSEstimate = 1208
+
+	// recordSizeBoostThreshold is the number of bytes of application data
+	// sent after which the TLS record size will be increased to the
+	// maximum.
+	recordSizeBoostThreshold = 128 * 1024
+)
+
+func (c *Conn) maxPayloadSizeForWrite(typ uint16) int {
+	if /*c.config.DynamicRecordSizingDisabled ||*/ typ != recordTypeApplicationData {
+		return maxPlaintext
+	}
+
+	if *c.rawConn.PacketsSent >= recordSizeBoostThreshold {
+		return maxPlaintext
+	}
+
+	// Subtract TLS overheads to get the maximum payload size.
+	payloadBytes := tcpMSSEstimate - recordHeaderLen - c.rawConn.Out.ExplicitNonceLen()
+	if rawCipher := *c.rawConn.Out.Cipher; rawCipher != nil {
+		switch ciph := rawCipher.(type) {
+		case cipher.Stream:
+			payloadBytes -= (*c.rawConn.Out.Mac).Size()
+		case cipher.AEAD:
+			payloadBytes -= ciph.Overhead()
+		/*case cbcMode:
+		blockSize := ciph.BlockSize()
+		// The payload must fit in a multiple of blockSize, with
+		// room for at least one padding byte.
+		payloadBytes = (payloadBytes & ^(blockSize - 1)) - 1
+		// The RawMac is appended before padding so affects the
+		// payload size directly.
+		payloadBytes -= c.out.mac.Size()*/
+		default:
+			panic("unknown cipher type")
+		}
+	}
+	if *c.rawConn.Vers == tls.VersionTLS13 {
+		payloadBytes-- // encrypted ContentType
+	}
+
+	// Allow packet growth in arithmetic progression up to max.
+	pkt := *c.rawConn.PacketsSent
+	*c.rawConn.PacketsSent++
+	if pkt > 1000 {
+		return maxPlaintext // avoid overflow in multiply below
+	}
+
+	n := payloadBytes * int(pkt+1)
+	if n > maxPlaintext {
+		n = maxPlaintext
+	}
+	return n
+}

common/listener/listener_tcp.go

@@ -3,6 +3,7 @@ package listener
 import (
 	"net"
 	"net/netip"
+	"strings"
 	"syscall"
 	"time"
 
@@ -56,7 +57,7 @@ func (l *Listener) ListenTCP() (net.Listener, error) {
 	if l.tproxy {
 		listenConfig.Control = control.Append(listenConfig.Control, func(network, address string, conn syscall.RawConn) error {
 			return control.Raw(conn, func(fd uintptr) error {
-				return redir.TProxy(fd, !M.ParseSocksaddr(address).IsIPv4(), false)
+				return redir.TProxy(fd, !strings.HasSuffix(network, "4"), false)
 			})
 		})
 	}

common/listener/listener_udp.go

@@ -5,6 +5,7 @@ import (
 	"net"
 	"net/netip"
 	"os"
+	"strings"
 	"syscall"
 
 	"github.com/sagernet/sing-box/adapter"
@@ -41,7 +42,7 @@ func (l *Listener) ListenUDP() (net.PacketConn, error) {
 	if l.tproxy {
 		listenConfig.Control = control.Append(listenConfig.Control, func(network, address string, conn syscall.RawConn) error {
 			return control.Raw(conn, func(fd uintptr) error {
-				return redir.TProxy(fd, !M.ParseSocksaddr(address).IsIPv4(), true)
+				return redir.TProxy(fd, !strings.HasSuffix(network, "4"), true)
 			})
 		})
 	}
@@ -164,9 +165,8 @@ func (l *Listener) loopUDPOut() {
 				if l.shutdown.Load() && E.IsClosed(err) {
 					return
 				}
-				l.udpConn.Close()
 				l.logger.Error("udp listener write back: ", destination, ": ", err)
-				return
+				continue
 			}
 			continue
 		case <-l.packetOutboundClosed:

common/process/searcher_darwin.go

@@ -96,11 +96,11 @@ func findProcessName(network string, ip netip.Addr, port int) (string, error) {
 		switch {
 		case flag&0x1 > 0 && isIPv4:
 			// ipv4
-			srcIP = netip.AddrFrom4(*(*[4]byte)(buf[inp+76 : inp+80]))
+			srcIP = netip.AddrFrom4([4]byte(buf[inp+76 : inp+80]))
 			srcIsIPv4 = true
 		case flag&0x2 > 0 && !isIPv4:
 			// ipv6
-			srcIP = netip.AddrFrom16(*(*[16]byte)(buf[inp+64 : inp+80]))
+			srcIP = netip.AddrFrom16([16]byte(buf[inp+64 : inp+80]))
 		default:
 			continue
 		}

common/sniff/quic_blacklist.go

@@ -17,8 +17,5 @@ var uQUICChrome115 = &ja3.ClientHello{
 }
 
 func maybeUQUIC(fingerprint *ja3.ClientHello) bool {
-	if uQUICChrome115.Equals(fingerprint, true) {
-		return true
-	}
-	return false
+	return !uQUICChrome115.Equals(fingerprint, true)
 }

common/sniff/quic_test.go

@@ -56,7 +56,7 @@ func TestSniffUQUICChrome115(t *testing.T) {
 	err = sniff.QUICClientHello(context.Background(), &metadata, pkt)
 	require.NoError(t, err)
 	require.Equal(t, metadata.Protocol, C.ProtocolQUIC)
-	require.Equal(t, metadata.Client, C.ClientQUICGo)
+	require.Equal(t, metadata.Client, C.ClientChromium)
 	require.Equal(t, metadata.Domain, "www.google.com")
 }
 

common/srs/binary.go

@@ -12,6 +12,8 @@ import (
 	"github.com/sagernet/sing/common"
 	"github.com/sagernet/sing/common/domain"
 	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/json/badjson"
+	"github.com/sagernet/sing/common/json/badoption"
 	"github.com/sagernet/sing/common/varbin"
 
 	"go4.org/netipx"
@@ -41,6 +43,8 @@ const (
 	ruleItemNetworkType
 	ruleItemNetworkIsExpensive
 	ruleItemNetworkIsConstrained
+	ruleItemNetworkInterfaceAddress
+	ruleItemDefaultInterfaceAddress
 	ruleItemFinal uint8 = 0xFF
 )
 
@@ -230,6 +234,51 @@ func readDefaultRule(reader varbin.Reader, recover bool) (rule option.DefaultHea
 			rule.NetworkIsExpensive = true
 		case ruleItemNetworkIsConstrained:
 			rule.NetworkIsConstrained = true
+		case ruleItemNetworkInterfaceAddress:
+			rule.NetworkInterfaceAddress = new(badjson.TypedMap[option.InterfaceType, badoption.Listable[*badoption.Prefixable]])
+			var size uint64
+			size, err = binary.ReadUvarint(reader)
+			if err != nil {
+				return
+			}
+			for i := uint64(0); i < size; i++ {
+				var key uint8
+				err = binary.Read(reader, binary.BigEndian, &key)
+				if err != nil {
+					return
+				}
+				var value []*badoption.Prefixable
+				var prefixCount uint64
+				prefixCount, err = binary.ReadUvarint(reader)
+				if err != nil {
+					return
+				}
+				for j := uint64(0); j < prefixCount; j++ {
+					var prefix netip.Prefix
+					prefix, err = readPrefix(reader)
+					if err != nil {
+						return
+					}
+					value = append(value, common.Ptr(badoption.Prefixable(prefix)))
+				}
+				rule.NetworkInterfaceAddress.Put(option.InterfaceType(key), value)
+			}
+		case ruleItemDefaultInterfaceAddress:
+			var value []*badoption.Prefixable
+			var prefixCount uint64
+			prefixCount, err = binary.ReadUvarint(reader)
+			if err != nil {
+				return
+			}
+			for j := uint64(0); j < prefixCount; j++ {
+				var prefix netip.Prefix
+				prefix, err = readPrefix(reader)
+				if err != nil {
+					return
+				}
+				value = append(value, common.Ptr(badoption.Prefixable(prefix)))
+			}
+			rule.DefaultInterfaceAddress = value
 		case ruleItemFinal:
 			err = binary.Read(reader, binary.BigEndian, &rule.Invert)
 			return
@@ -346,7 +395,7 @@ func writeDefaultRule(writer varbin.Writer, rule option.DefaultHeadlessRule, gen
 	}
 	if len(rule.NetworkType) > 0 {
 		if generateVersion < C.RuleSetVersion3 {
-			return E.New("network_type rule item is only supported in version 3 or later")
+			return E.New("`network_type` rule item is only supported in version 3 or later")
 		}
 		err = writeRuleItemUint8(writer, ruleItemNetworkType, rule.NetworkType)
 		if err != nil {
@@ -354,17 +403,71 @@ func writeDefaultRule(writer varbin.Writer, rule option.DefaultHeadlessRule, gen
 		}
 	}
 	if rule.NetworkIsExpensive {
+		if generateVersion < C.RuleSetVersion3 {
+			return E.New("`network_is_expensive` rule item is only supported in version 3 or later")
+		}
 		err = binary.Write(writer, binary.BigEndian, ruleItemNetworkIsExpensive)
 		if err != nil {
 			return err
 		}
 	}
 	if rule.NetworkIsConstrained {
+		if generateVersion < C.RuleSetVersion3 {
+			return E.New("`network_is_constrained` rule item is only supported in version 3 or later")
+		}
 		err = binary.Write(writer, binary.BigEndian, ruleItemNetworkIsConstrained)
 		if err != nil {
 			return err
 		}
 	}
+	if rule.NetworkInterfaceAddress != nil && rule.NetworkInterfaceAddress.Size() > 0 {
+		if generateVersion < C.RuleSetVersion4 {
+			return E.New("`network_interface_address` rule item is only supported in version 4 or later")
+		}
+		err = writer.WriteByte(ruleItemNetworkInterfaceAddress)
+		if err != nil {
+			return err
+		}
+		_, err = varbin.WriteUvarint(writer, uint64(rule.NetworkInterfaceAddress.Size()))
+		if err != nil {
+			return err
+		}
+		for _, entry := range rule.NetworkInterfaceAddress.Entries() {
+			err = binary.Write(writer, binary.BigEndian, uint8(entry.Key.Build()))
+			if err != nil {
+				return err
+			}
+			_, err = varbin.WriteUvarint(writer, uint64(len(entry.Value)))
+			if err != nil {
+				return err
+			}
+			for _, rawPrefix := range entry.Value {
+				err = writePrefix(writer, rawPrefix.Build(netip.Prefix{}))
+				if err != nil {
+					return err
+				}
+			}
+		}
+	}
+	if len(rule.DefaultInterfaceAddress) > 0 {
+		if generateVersion < C.RuleSetVersion4 {
+			return E.New("`default_interface_address` rule item is only supported in version 4 or later")
+		}
+		err = writer.WriteByte(ruleItemDefaultInterfaceAddress)
+		if err != nil {
+			return err
+		}
+		_, err = varbin.WriteUvarint(writer, uint64(len(rule.DefaultInterfaceAddress)))
+		if err != nil {
+			return err
+		}
+		for _, rawPrefix := range rule.DefaultInterfaceAddress {
+			err = writePrefix(writer, rawPrefix.Build(netip.Prefix{}))
+			if err != nil {
+				return err
+			}
+		}
+	}
 	if len(rule.WIFISSID) > 0 {
 		err = writeRuleItemString(writer, ruleItemWIFISSID, rule.WIFISSID)
 		if err != nil {

common/srs/ip_cidr.go

@@ -0,0 +1,33 @@
+package srs
+
+import (
+	"encoding/binary"
+	"net/netip"
+
+	M "github.com/sagernet/sing/common/metadata"
+	"github.com/sagernet/sing/common/varbin"
+)
+
+func readPrefix(reader varbin.Reader) (netip.Prefix, error) {
+	addrSlice, err := varbin.ReadValue[[]byte](reader, binary.BigEndian)
+	if err != nil {
+		return netip.Prefix{}, err
+	}
+	prefixBits, err := varbin.ReadValue[uint8](reader, binary.BigEndian)
+	if err != nil {
+		return netip.Prefix{}, err
+	}
+	return netip.PrefixFrom(M.AddrFromIP(addrSlice), int(prefixBits)), nil
+}
+
+func writePrefix(writer varbin.Writer, prefix netip.Prefix) error {
+	err := varbin.Write(writer, binary.BigEndian, prefix.Addr().AsSlice())
+	if err != nil {
+		return err
+	}
+	err = binary.Write(writer, binary.BigEndian, uint8(prefix.Bits()))
+	if err != nil {
+		return err
+	}
+	return nil
+}

common/tls/client.go

@@ -2,39 +2,71 @@ package tls
 
 import (
 	"context"
+	"crypto/tls"
+	"errors"
 	"net"
 	"os"
 
-	"github.com/sagernet/sing-box/adapter"
 	"github.com/sagernet/sing-box/common/badtls"
 	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing/common/logger"
 	M "github.com/sagernet/sing/common/metadata"
 	N "github.com/sagernet/sing/common/network"
 	aTLS "github.com/sagernet/sing/common/tls"
 )
 
-func NewDialerFromOptions(ctx context.Context, router adapter.Router, dialer N.Dialer, serverAddress string, options option.OutboundTLSOptions) (N.Dialer, error) {
+func NewDialerFromOptions(ctx context.Context, logger logger.ContextLogger, dialer N.Dialer, serverAddress string, options option.OutboundTLSOptions) (N.Dialer, error) {
 	if !options.Enabled {
 		return dialer, nil
 	}
-	config, err := NewClient(ctx, serverAddress, options)
+	config, err := NewClientWithOptions(ClientOptions{
+		Context:       ctx,
+		Logger:        logger,
+		ServerAddress: serverAddress,
+		Options:       options,
+	})
 	if err != nil {
 		return nil, err
 	}
 	return NewDialer(dialer, config), nil
 }
 
-func NewClient(ctx context.Context, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
-	if !options.Enabled {
+func NewClient(ctx context.Context, logger logger.ContextLogger, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
+	return NewClientWithOptions(ClientOptions{
+		Context:       ctx,
+		Logger:        logger,
+		ServerAddress: serverAddress,
+		Options:       options,
+	})
+}
+
+type ClientOptions struct {
+	Context        context.Context
+	Logger         logger.ContextLogger
+	ServerAddress  string
+	Options        option.OutboundTLSOptions
+	KTLSCompatible bool
+}
+
+func NewClientWithOptions(options ClientOptions) (Config, error) {
+	if !options.Options.Enabled {
 		return nil, nil
 	}
-	if options.Reality != nil && options.Reality.Enabled {
-		return NewRealityClient(ctx, serverAddress, options)
-	} else if options.UTLS != nil && options.UTLS.Enabled {
-		return NewUTLSClient(ctx, serverAddress, options)
+	if !options.KTLSCompatible {
+		if options.Options.KernelTx {
+			options.Logger.Warn("enabling kTLS TX in current scenarios will definitely reduce performance, please checkout https://sing-box.sagernet.org/configuration/shared/tls/#kernel_tx")
+		}
 	}
-	return NewSTDClient(ctx, serverAddress, options)
+	if options.Options.KernelRx {
+		options.Logger.Warn("enabling kTLS RX will definitely reduce performance, please checkout https://sing-box.sagernet.org/configuration/shared/tls/#kernel_rx")
+	}
+	if options.Options.Reality != nil && options.Options.Reality.Enabled {
+		return NewRealityClient(options.Context, options.Logger, options.ServerAddress, options.Options)
+	} else if options.Options.UTLS != nil && options.Options.UTLS.Enabled {
+		return NewUTLSClient(options.Context, options.Logger, options.ServerAddress, options.Options)
+	}
+	return NewSTDClient(options.Context, options.Logger, options.ServerAddress, options.Options)
 }
 
 func ClientHandshake(ctx context.Context, conn net.Conn, config Config) (Conn, error) {
@@ -53,26 +85,57 @@ func ClientHandshake(ctx context.Context, conn net.Conn, config Config) (Conn, e
 	return tlsConn, nil
 }
 
-type Dialer struct {
+type Dialer interface {
+	N.Dialer
+	DialTLSContext(ctx context.Context, destination M.Socksaddr) (Conn, error)
+}
+
+type defaultDialer struct {
 	dialer N.Dialer
 	config Config
 }
 
-func NewDialer(dialer N.Dialer, config Config) N.Dialer {
-	return &Dialer{dialer, config}
+func NewDialer(dialer N.Dialer, config Config) Dialer {
+	return &defaultDialer{dialer, config}
 }
 
-func (d *Dialer) DialContext(ctx context.Context, network string, destination M.Socksaddr) (net.Conn, error) {
-	if network != N.NetworkTCP {
+func (d *defaultDialer) DialContext(ctx context.Context, network string, destination M.Socksaddr) (net.Conn, error) {
+	if N.NetworkName(network) != N.NetworkTCP {
 		return nil, os.ErrInvalid
 	}
-	conn, err := d.dialer.DialContext(ctx, network, destination)
+	return d.DialTLSContext(ctx, destination)
+}
+
+func (d *defaultDialer) ListenPacket(ctx context.Context, destination M.Socksaddr) (net.PacketConn, error) {
+	return nil, os.ErrInvalid
+}
+
+func (d *defaultDialer) DialTLSContext(ctx context.Context, destination M.Socksaddr) (Conn, error) {
+	return d.dialContext(ctx, destination, true)
+}
+
+func (d *defaultDialer) dialContext(ctx context.Context, destination M.Socksaddr, echRetry bool) (Conn, error) {
+	conn, err := d.dialer.DialContext(ctx, N.NetworkTCP, destination)
 	if err != nil {
 		return nil, err
 	}
-	return ClientHandshake(ctx, conn, d.config)
+	tlsConn, err := ClientHandshake(ctx, conn, d.config)
+	if err == nil {
+		return tlsConn, nil
+	}
+	conn.Close()
+	if echRetry {
+		var echErr *tls.ECHRejectionError
+		if errors.As(err, &echErr) && len(echErr.RetryConfigList) > 0 {
+			if echConfig, isECH := d.config.(ECHCapableConfig); isECH {
+				echConfig.SetECHConfigList(echErr.RetryConfigList)
+			}
+		}
+		return d.dialContext(ctx, destination, false)
+	}
+	return nil, err
 }
 
-func (d *Dialer) ListenPacket(ctx context.Context, destination M.Socksaddr) (net.PacketConn, error) {
-	return nil, os.ErrInvalid
+func (d *defaultDialer) Upstream() any {
+	return d.dialer
 }

common/tls/ech.go

@@ -69,11 +69,7 @@ func parseECHServerConfig(ctx context.Context, options option.InboundTLSOptions,
 	} else {
 		return E.New("missing ECH keys")
 	}
-	block, rest := pem.Decode(echKey)
-	if block == nil || block.Type != "ECH KEYS" || len(rest) > 0 {
-		return E.New("invalid ECH keys pem")
-	}
-	echKeys, err := UnmarshalECHKeys(block.Bytes)
+	echKeys, err := parseECHKeys(echKey)
 	if err != nil {
 		return E.Cause(err, "parse ECH keys")
 	}
@@ -85,21 +81,29 @@ func parseECHServerConfig(ctx context.Context, options option.InboundTLSOptions,
 	return nil
 }
 
-func reloadECHKeys(echKeyPath string, tlsConfig *tls.Config) error {
-	echKey, err := os.ReadFile(echKeyPath)
+func (c *STDServerConfig) setECHServerConfig(echKey []byte) error {
+	echKeys, err := parseECHKeys(echKey)
 	if err != nil {
-		return E.Cause(err, "reload ECH keys from ", echKeyPath)
+		return err
 	}
+	c.access.Lock()
+	config := c.config.Clone()
+	config.EncryptedClientHelloKeys = echKeys
+	c.config = config
+	c.access.Unlock()
+	return nil
+}
+
+func parseECHKeys(echKey []byte) ([]tls.EncryptedClientHelloKey, error) {
 	block, _ := pem.Decode(echKey)
 	if block == nil || block.Type != "ECH KEYS" {
-		return E.New("invalid ECH keys pem")
+		return nil, E.New("invalid ECH keys pem")
 	}
 	echKeys, err := UnmarshalECHKeys(block.Bytes)
 	if err != nil {
-		return E.Cause(err, "parse ECH keys")
+		return nil, E.Cause(err, "parse ECH keys")
 	}
-	tlsConfig.EncryptedClientHelloKeys = echKeys
-	return nil
+	return echKeys, nil
 }
 
 type ECHClientConfig struct {
@@ -125,7 +129,7 @@ func (s *ECHClientConfig) ClientHandshake(ctx context.Context, conn net.Conn) (a
 func (s *ECHClientConfig) fetchAndHandshake(ctx context.Context, conn net.Conn) (aTLS.Conn, error) {
 	s.access.Lock()
 	defer s.access.Unlock()
-	if len(s.ECHConfigList()) == 0 || s.lastTTL == 0 || time.Now().Sub(s.lastUpdate) > s.lastTTL {
+	if len(s.ECHConfigList()) == 0 || s.lastTTL == 0 || time.Since(s.lastUpdate) > s.lastTTL {
 		message := &mDNS.Msg{
 			MsgHdr: mDNS.MsgHdr{
 				RecursionDesired: true,

common/tls/ech_shared.go

@@ -1,14 +1,11 @@
 package tls
 
 import (
-	"bytes"
-	"encoding/binary"
+	"crypto/ecdh"
+	"crypto/rand"
 	"encoding/pem"
 
-	E "github.com/sagernet/sing/common/exceptions"
-
-	"github.com/cloudflare/circl/hpke"
-	"github.com/cloudflare/circl/kem"
+	"golang.org/x/crypto/cryptobyte"
 )
 
 type ECHCapableConfig interface {
@@ -17,145 +14,68 @@ type ECHCapableConfig interface {
 	SetECHConfigList([]byte)
 }
 
-func ECHKeygenDefault(serverName string) (configPem string, keyPem string, err error) {
-	cipherSuites := []echCipherSuite{
-		{
-			kdf:  hpke.KDF_HKDF_SHA256,
-			aead: hpke.AEAD_AES128GCM,
-		}, {
-			kdf:  hpke.KDF_HKDF_SHA256,
-			aead: hpke.AEAD_ChaCha20Poly1305,
-		},
-	}
-	keyConfig := []myECHKeyConfig{
-		{id: 0, kem: hpke.KEM_X25519_HKDF_SHA256},
-	}
-
-	keyPairs, err := echKeygen(0xfe0d, serverName, keyConfig, cipherSuites)
+func ECHKeygenDefault(publicName string) (configPem string, keyPem string, err error) {
+	echKey, err := ecdh.X25519().GenerateKey(rand.Reader)
 	if err != nil {
 		return
 	}
-
-	var configBuffer bytes.Buffer
-	var totalLen uint16
-	for _, keyPair := range keyPairs {
-		totalLen += uint16(len(keyPair.rawConf))
+	echConfig, err := marshalECHConfig(0, echKey.PublicKey().Bytes(), publicName, 0)
+	if err != nil {
+		return
 	}
-	binary.Write(&configBuffer, binary.BigEndian, totalLen)
-	for _, keyPair := range keyPairs {
-		configBuffer.Write(keyPair.rawConf)
+	configBuilder := cryptobyte.NewBuilder(nil)
+	configBuilder.AddUint16LengthPrefixed(func(builder *cryptobyte.Builder) {
+		builder.AddBytes(echConfig)
+	})
+	configBytes, err := configBuilder.Bytes()
+	if err != nil {
+		return
 	}
-
-	var keyBuffer bytes.Buffer
-	for _, keyPair := range keyPairs {
-		keyBuffer.Write(keyPair.rawKey)
+	keyBuilder := cryptobyte.NewBuilder(nil)
+	keyBuilder.AddUint16LengthPrefixed(func(builder *cryptobyte.Builder) {
+		builder.AddBytes(echKey.Bytes())
+	})
+	keyBuilder.AddUint16LengthPrefixed(func(builder *cryptobyte.Builder) {
+		builder.AddBytes(echConfig)
+	})
+	keyBytes, err := keyBuilder.Bytes()
+	if err != nil {
+		return
 	}
-
-	configPem = string(pem.EncodeToMemory(&pem.Block{Type: "ECH CONFIGS", Bytes: configBuffer.Bytes()}))
-	keyPem = string(pem.EncodeToMemory(&pem.Block{Type: "ECH KEYS", Bytes: keyBuffer.Bytes()}))
+	configPem = string(pem.EncodeToMemory(&pem.Block{Type: "ECH CONFIGS", Bytes: configBytes}))
+	keyPem = string(pem.EncodeToMemory(&pem.Block{Type: "ECH KEYS", Bytes: keyBytes}))
 	return
 }
 
-type echKeyConfigPair struct {
-	id      uint8
-	rawKey  []byte
-	conf    myECHKeyConfig
-	rawConf []byte
-}
+func marshalECHConfig(id uint8, pubKey []byte, publicName string, maxNameLen uint8) ([]byte, error) {
+	const extensionEncryptedClientHello = 0xfe0d
+	const DHKEM_X25519_HKDF_SHA256 = 0x0020
+	const KDF_HKDF_SHA256 = 0x0001
+	builder := cryptobyte.NewBuilder(nil)
+	builder.AddUint16(extensionEncryptedClientHello)
+	builder.AddUint16LengthPrefixed(func(builder *cryptobyte.Builder) {
+		builder.AddUint8(id)
 
-type echCipherSuite struct {
-	kdf  hpke.KDF
-	aead hpke.AEAD
-}
-
-type myECHKeyConfig struct {
-	id   uint8
-	kem  hpke.KEM
-	seed []byte
-}
-
-func echKeygen(version uint16, serverName string, conf []myECHKeyConfig, suite []echCipherSuite) ([]echKeyConfigPair, error) {
-	be := binary.BigEndian
-	// prepare for future update
-	if version != 0xfe0d {
-		return nil, E.New("unsupported ECH version", version)
-	}
-
-	suiteBuf := make([]byte, 0, len(suite)*4+2)
-	suiteBuf = be.AppendUint16(suiteBuf, uint16(len(suite))*4)
-	for _, s := range suite {
-		if !s.kdf.IsValid() || !s.aead.IsValid() {
-			return nil, E.New("invalid HPKE cipher suite")
-		}
-		suiteBuf = be.AppendUint16(suiteBuf, uint16(s.kdf))
-		suiteBuf = be.AppendUint16(suiteBuf, uint16(s.aead))
-	}
-
-	pairs := []echKeyConfigPair{}
-	for _, c := range conf {
-		pair := echKeyConfigPair{}
-		pair.id = c.id
-		pair.conf = c
-
-		if !c.kem.IsValid() {
-			return nil, E.New("invalid HPKE KEM")
-		}
-
-		kpGenerator := c.kem.Scheme().GenerateKeyPair
-		if len(c.seed) > 0 {
-			kpGenerator = func() (kem.PublicKey, kem.PrivateKey, error) {
-				pub, sec := c.kem.Scheme().DeriveKeyPair(c.seed)
-				return pub, sec, nil
+		builder.AddUint16(DHKEM_X25519_HKDF_SHA256) // The only DHKEM we support
+		builder.AddUint16LengthPrefixed(func(builder *cryptobyte.Builder) {
+			builder.AddBytes(pubKey)
+		})
+		builder.AddUint16LengthPrefixed(func(builder *cryptobyte.Builder) {
+			const (
+				AEAD_AES_128_GCM      = 0x0001
+				AEAD_AES_256_GCM      = 0x0002
+				AEAD_ChaCha20Poly1305 = 0x0003
+			)
+			for _, aeadID := range []uint16{AEAD_AES_128_GCM, AEAD_AES_256_GCM, AEAD_ChaCha20Poly1305} {
+				builder.AddUint16(KDF_HKDF_SHA256) // The only KDF we support
+				builder.AddUint16(aeadID)
 			}
-			if len(c.seed) < c.kem.Scheme().PrivateKeySize() {
-				return nil, E.New("HPKE KEM seed too short")
-			}
-		}
-
-		pub, sec, err := kpGenerator()
-		if err != nil {
-			return nil, E.Cause(err, "generate ECH config key pair")
-		}
-		b := []byte{}
-		b = be.AppendUint16(b, version)
-		b = be.AppendUint16(b, 0) // length field
-		// contents
-		// key config
-		b = append(b, c.id)
-		b = be.AppendUint16(b, uint16(c.kem))
-		pubBuf, err := pub.MarshalBinary()
-		if err != nil {
-			return nil, E.Cause(err, "serialize ECH public key")
-		}
-		b = be.AppendUint16(b, uint16(len(pubBuf)))
-		b = append(b, pubBuf...)
-
-		b = append(b, suiteBuf...)
-		// end key config
-		// max name len, not supported
-		b = append(b, 0)
-		// server name
-		b = append(b, byte(len(serverName)))
-		b = append(b, []byte(serverName)...)
-		// extensions, not supported
-		b = be.AppendUint16(b, 0)
-
-		be.PutUint16(b[2:], uint16(len(b)-4))
-
-		pair.rawConf = b
-
-		secBuf, err := sec.MarshalBinary()
-		if err != nil {
-			return nil, E.Cause(err, "serialize ECH private key")
-		}
-		sk := []byte{}
-		sk = be.AppendUint16(sk, uint16(len(secBuf)))
-		sk = append(sk, secBuf...)
-		sk = be.AppendUint16(sk, uint16(len(b)))
-		sk = append(sk, b...)
-		pair.rawKey = sk
-
-		pairs = append(pairs, pair)
-	}
-	return pairs, nil
+		})
+		builder.AddUint8(maxNameLen)
+		builder.AddUint8LengthPrefixed(func(builder *cryptobyte.Builder) {
+			builder.AddBytes([]byte(publicName))
+		})
+		builder.AddUint16(0) // extensions
+	})
+	return builder.Bytes()
 }

common/tls/ech_stub.go

@@ -18,6 +18,6 @@ func parseECHServerConfig(ctx context.Context, options option.InboundTLSOptions,
 	return E.New("ECH requires go1.24, please recompile your binary.")
 }
 
-func reloadECHKeys(echKeyPath string, tlsConfig *tls.Config) error {
-	return E.New("ECH requires go1.24, please recompile your binary.")
+func (c *STDServerConfig) setECHServerConfig(echKey []byte) error {
+	panic("unreachable")
 }

common/tls/ktls.go

@@ -0,0 +1,67 @@
+package tls
+
+import (
+	"context"
+	"net"
+
+	"github.com/sagernet/sing-box/common/ktls"
+	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
+	aTLS "github.com/sagernet/sing/common/tls"
+)
+
+type KTLSClientConfig struct {
+	Config
+	logger             logger.ContextLogger
+	kernelTx, kernelRx bool
+}
+
+func (w *KTLSClientConfig) ClientHandshake(ctx context.Context, conn net.Conn) (aTLS.Conn, error) {
+	tlsConn, err := aTLS.ClientHandshake(ctx, conn, w.Config)
+	if err != nil {
+		return nil, err
+	}
+	kConn, err := ktls.NewConn(ctx, w.logger, tlsConn, w.kernelTx, w.kernelRx)
+	if err != nil {
+		tlsConn.Close()
+		return nil, E.Cause(err, "initialize kernel TLS")
+	}
+	return kConn, nil
+}
+
+func (w *KTLSClientConfig) Clone() Config {
+	return &KTLSClientConfig{
+		w.Config.Clone(),
+		w.logger,
+		w.kernelTx,
+		w.kernelRx,
+	}
+}
+
+type KTlSServerConfig struct {
+	ServerConfig
+	logger             logger.ContextLogger
+	kernelTx, kernelRx bool
+}
+
+func (w *KTlSServerConfig) ServerHandshake(ctx context.Context, conn net.Conn) (aTLS.Conn, error) {
+	tlsConn, err := aTLS.ServerHandshake(ctx, conn, w.ServerConfig)
+	if err != nil {
+		return nil, err
+	}
+	kConn, err := ktls.NewConn(ctx, w.logger, tlsConn, w.kernelTx, w.kernelRx)
+	if err != nil {
+		tlsConn.Close()
+		return nil, E.Cause(err, "initialize kernel TLS")
+	}
+	return kConn, nil
+}
+
+func (w *KTlSServerConfig) Clone() Config {
+	return &KTlSServerConfig{
+		w.ServerConfig.Clone().(ServerConfig),
+		w.logger,
+		w.kernelTx,
+		w.kernelRx,
+	}
+}

common/tls/reality_client.go

@@ -28,10 +28,12 @@ import (
 	"unsafe"
 
 	"github.com/sagernet/sing-box/adapter"
+	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/option"
 	"github.com/sagernet/sing/common"
 	"github.com/sagernet/sing/common/debug"
 	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
 	"github.com/sagernet/sing/common/ntp"
 	aTLS "github.com/sagernet/sing/common/tls"
 
@@ -49,12 +51,12 @@ type RealityClientConfig struct {
 	shortID   [8]byte
 }
 
-func NewRealityClient(ctx context.Context, serverAddress string, options option.OutboundTLSOptions) (*RealityClientConfig, error) {
+func NewRealityClient(ctx context.Context, logger logger.ContextLogger, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
 	if options.UTLS == nil || !options.UTLS.Enabled {
 		return nil, E.New("uTLS is required by reality client")
 	}
 
-	uClient, err := NewUTLSClient(ctx, serverAddress, options)
+	uClient, err := NewUTLSClient(ctx, logger, serverAddress, options)
 	if err != nil {
 		return nil, err
 	}
@@ -74,7 +76,20 @@ func NewRealityClient(ctx context.Context, serverAddress string, options option.
 	if decodedLen > 8 {
 		return nil, E.New("invalid short_id")
 	}
-	return &RealityClientConfig{ctx, uClient.(*UTLSClientConfig), publicKey, shortID}, nil
+
+	var config Config = &RealityClientConfig{ctx, uClient.(*UTLSClientConfig), publicKey, shortID}
+	if options.KernelRx || options.KernelTx {
+		if !C.IsLinux {
+			return nil, E.New("kTLS is only supported on Linux")
+		}
+		config = &KTLSClientConfig{
+			Config:   config,
+			logger:   logger,
+			kernelTx: options.KernelTx,
+			kernelRx: options.KernelRx,
+		}
+	}
+	return config, nil
 }
 
 func (e *RealityClientConfig) ServerName() string {
@@ -93,7 +108,7 @@ func (e *RealityClientConfig) SetNextProtos(nextProto []string) {
 	e.uClient.SetNextProtos(nextProto)
 }
 
-func (e *RealityClientConfig) Config() (*STDConfig, error) {
+func (e *RealityClientConfig) STDConfig() (*STDConfig, error) {
 	return nil, E.New("unsupported usage for reality")
 }
 
@@ -307,3 +322,11 @@ func (c *realityClientConnWrapper) Upstream() any {
 func (c *realityClientConnWrapper) CloseWrite() error {
 	return c.Close()
 }
+
+func (c *realityClientConnWrapper) ReaderReplaceable() bool {
+	return true
+}
+
+func (c *realityClientConnWrapper) WriterReplaceable() bool {
+	return true
+}

common/tls/reality_server.go

@@ -12,6 +12,7 @@ import (
 	"time"
 
 	"github.com/sagernet/sing-box/common/dialer"
+	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
 	E "github.com/sagernet/sing/common/exceptions"
@@ -28,7 +29,7 @@ type RealityServerConfig struct {
 	config *utls.RealityConfig
 }
 
-func NewRealityServer(ctx context.Context, logger log.Logger, options option.InboundTLSOptions) (*RealityServerConfig, error) {
+func NewRealityServer(ctx context.Context, logger log.ContextLogger, options option.InboundTLSOptions) (ServerConfig, error) {
 	var tlsConfig utls.RealityConfig
 
 	if options.ACME != nil && len(options.ACME.Domain) > 0 {
@@ -119,7 +120,22 @@ func NewRealityServer(ctx context.Context, logger log.Logger, options option.Inb
 		return handshakeDialer.DialContext(ctx, network, M.ParseSocksaddr(addr))
 	}
 
-	return &RealityServerConfig{&tlsConfig}, nil
+	if options.ECH != nil && options.ECH.Enabled {
+		return nil, E.New("Reality is conflict with ECH")
+	}
+	var config ServerConfig = &RealityServerConfig{&tlsConfig}
+	if options.KernelTx || options.KernelRx {
+		if !C.IsLinux {
+			return nil, E.New("kTLS is only supported on Linux")
+		}
+		config = &KTlSServerConfig{
+			ServerConfig: config,
+			logger:       logger,
+			kernelTx:     options.KernelTx,
+			kernelRx:     options.KernelRx,
+		}
+	}
+	return config, nil
 }
 
 func (c *RealityServerConfig) ServerName() string {
@@ -138,7 +154,7 @@ func (c *RealityServerConfig) SetNextProtos(nextProto []string) {
 	c.config.NextProtos = nextProto
 }
 
-func (c *RealityServerConfig) Config() (*tls.Config, error) {
+func (c *RealityServerConfig) STDConfig() (*tls.Config, error) {
 	return nil, E.New("unsupported usage for reality")
 }
 
@@ -206,3 +222,11 @@ func (c *realityConnWrapper) Upstream() any {
 func (c *realityConnWrapper) CloseWrite() error {
 	return c.Close()
 }
+
+func (c *realityConnWrapper) ReaderReplaceable() bool {
+	return true
+}
+
+func (c *realityConnWrapper) WriterReplaceable() bool {
+	return true
+}

common/tls/server.go

@@ -12,14 +12,37 @@ import (
 	aTLS "github.com/sagernet/sing/common/tls"
 )
 
-func NewServer(ctx context.Context, logger log.Logger, options option.InboundTLSOptions) (ServerConfig, error) {
-	if !options.Enabled {
+type ServerOptions struct {
+	Context        context.Context
+	Logger         log.ContextLogger
+	Options        option.InboundTLSOptions
+	KTLSCompatible bool
+}
+
+func NewServer(ctx context.Context, logger log.ContextLogger, options option.InboundTLSOptions) (ServerConfig, error) {
+	return NewServerWithOptions(ServerOptions{
+		Context: ctx,
+		Logger:  logger,
+		Options: options,
+	})
+}
+
+func NewServerWithOptions(options ServerOptions) (ServerConfig, error) {
+	if !options.Options.Enabled {
 		return nil, nil
 	}
-	if options.Reality != nil && options.Reality.Enabled {
-		return NewRealityServer(ctx, logger, options)
+	if !options.KTLSCompatible {
+		if options.Options.KernelTx {
+			options.Logger.Warn("enabling kTLS TX in current scenarios will definitely reduce performance, please checkout https://sing-box.sagernet.org/configuration/shared/tls/#kernel_tx")
+		}
 	}
-	return NewSTDServer(ctx, logger, options)
+	if options.Options.KernelRx {
+		options.Logger.Warn("enabling kTLS RX will definitely reduce performance, please checkout https://sing-box.sagernet.org/configuration/shared/tls/#kernel_rx")
+	}
+	if options.Options.Reality != nil && options.Options.Reality.Enabled {
+		return NewRealityServer(options.Context, options.Logger, options.Options)
+	}
+	return NewSTDServer(options.Context, options.Logger, options.Options)
 }
 
 func ServerHandshake(ctx context.Context, conn net.Conn, config ServerConfig) (Conn, error) {

common/tls/std_client.go

@@ -11,8 +11,10 @@ import (
 
 	"github.com/sagernet/sing-box/adapter"
 	"github.com/sagernet/sing-box/common/tlsfragment"
+	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/option"
 	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
 	"github.com/sagernet/sing/common/ntp"
 )
 
@@ -40,7 +42,7 @@ func (c *STDClientConfig) SetNextProtos(nextProto []string) {
 	c.config.NextProtos = nextProto
 }
 
-func (c *STDClientConfig) Config() (*STDConfig, error) {
+func (c *STDClientConfig) STDConfig() (*STDConfig, error) {
 	return c.config, nil
 }
 
@@ -52,7 +54,13 @@ func (c *STDClientConfig) Client(conn net.Conn) (Conn, error) {
 }
 
 func (c *STDClientConfig) Clone() Config {
-	return &STDClientConfig{c.ctx, c.config.Clone(), c.fragment, c.fragmentFallbackDelay, c.recordFragment}
+	return &STDClientConfig{
+		ctx:                   c.ctx,
+		config:                c.config.Clone(),
+		fragment:              c.fragment,
+		fragmentFallbackDelay: c.fragmentFallbackDelay,
+		recordFragment:        c.recordFragment,
+	}
 }
 
 func (c *STDClientConfig) ECHConfigList() []byte {
@@ -63,7 +71,7 @@ func (c *STDClientConfig) SetECHConfigList(EncryptedClientHelloConfigList []byte
 	c.config.EncryptedClientHelloConfigList = EncryptedClientHelloConfigList
 }
 
-func NewSTDClient(ctx context.Context, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
+func NewSTDClient(ctx context.Context, logger logger.ContextLogger, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
 	var serverName string
 	if options.ServerName != "" {
 		serverName = options.ServerName
@@ -86,12 +94,16 @@ func NewSTDClient(ctx context.Context, serverAddress string, options option.Outb
 		tlsConfig.InsecureSkipVerify = true
 		tlsConfig.VerifyConnection = func(state tls.ConnectionState) error {
 			verifyOptions := x509.VerifyOptions{
+				Roots:         tlsConfig.RootCAs,
 				DNSName:       serverName,
 				Intermediates: x509.NewCertPool(),
 			}
 			for _, cert := range state.PeerCertificates[1:] {
 				verifyOptions.Intermediates.AddCert(cert)
 			}
+			if tlsConfig.Time != nil {
+				verifyOptions.CurrentTime = tlsConfig.Time()
+			}
 			_, err := state.PeerCertificates[0].Verify(verifyOptions)
 			return err
 		}
@@ -142,10 +154,24 @@ func NewSTDClient(ctx context.Context, serverAddress string, options option.Outb
 		}
 		tlsConfig.RootCAs = certPool
 	}
-	stdConfig := &STDClientConfig{ctx, &tlsConfig, options.Fragment, time.Duration(options.FragmentFallbackDelay), options.RecordFragment}
+	var config Config = &STDClientConfig{ctx, &tlsConfig, options.Fragment, time.Duration(options.FragmentFallbackDelay), options.RecordFragment}
 	if options.ECH != nil && options.ECH.Enabled {
-		return parseECHClientConfig(ctx, stdConfig, options)
-	} else {
-		return stdConfig, nil
+		var err error
+		config, err = parseECHClientConfig(ctx, config.(ECHCapableConfig), options)
+		if err != nil {
+			return nil, err
+		}
 	}
+	if options.KernelRx || options.KernelTx {
+		if !C.IsLinux {
+			return nil, E.New("kTLS is only supported on Linux")
+		}
+		config = &KTLSClientConfig{
+			Config:   config,
+			logger:   logger,
+			kernelTx: options.KernelTx,
+			kernelRx: options.KernelRx,
+		}
+	}
+	return config, nil
 }

common/tls/std_server.go

@@ -6,10 +6,12 @@ import (
 	"net"
 	"os"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/sagernet/fswatch"
 	"github.com/sagernet/sing-box/adapter"
+	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
 	"github.com/sagernet/sing/common"
@@ -20,6 +22,7 @@ import (
 var errInsecureUnused = E.New("tls: insecure unused")
 
 type STDServerConfig struct {
+	access          sync.RWMutex
 	config          *tls.Config
 	logger          log.Logger
 	acmeService     adapter.SimpleLifecycle
@@ -32,14 +35,22 @@ type STDServerConfig struct {
 }
 
 func (c *STDServerConfig) ServerName() string {
+	c.access.RLock()
+	defer c.access.RUnlock()
 	return c.config.ServerName
 }
 
 func (c *STDServerConfig) SetServerName(serverName string) {
-	c.config.ServerName = serverName
+	c.access.Lock()
+	defer c.access.Unlock()
+	config := c.config.Clone()
+	config.ServerName = serverName
+	c.config = config
 }
 
 func (c *STDServerConfig) NextProtos() []string {
+	c.access.RLock()
+	defer c.access.RUnlock()
 	if c.acmeService != nil && len(c.config.NextProtos) > 1 && c.config.NextProtos[0] == ACMETLS1Protocol {
 		return c.config.NextProtos[1:]
 	} else {
@@ -48,14 +59,18 @@ func (c *STDServerConfig) NextProtos() []string {
 }
 
 func (c *STDServerConfig) SetNextProtos(nextProto []string) {
+	c.access.Lock()
+	defer c.access.Unlock()
+	config := c.config.Clone()
 	if c.acmeService != nil && len(c.config.NextProtos) > 1 && c.config.NextProtos[0] == ACMETLS1Protocol {
-		c.config.NextProtos = append(c.config.NextProtos[:1], nextProto...)
+		config.NextProtos = append(c.config.NextProtos[:1], nextProto...)
 	} else {
-		c.config.NextProtos = nextProto
+		config.NextProtos = nextProto
 	}
+	c.config = config
 }
 
-func (c *STDServerConfig) Config() (*STDConfig, error) {
+func (c *STDServerConfig) STDConfig() (*STDConfig, error) {
 	return c.config, nil
 }
 
@@ -77,9 +92,6 @@ func (c *STDServerConfig) Start() error {
 	if c.acmeService != nil {
 		return c.acmeService.Start()
 	} else {
-		if c.certificatePath == "" && c.keyPath == "" {
-			return nil
-		}
 		err := c.startWatcher()
 		if err != nil {
 			c.logger.Warn("create fsnotify watcher: ", err)
@@ -99,6 +111,9 @@ func (c *STDServerConfig) startWatcher() error {
 	if c.echKeyPath != "" {
 		watchPath = append(watchPath, c.echKeyPath)
 	}
+	if len(watchPath) == 0 {
+		return nil
+	}
 	watcher, err := fswatch.NewWatcher(fswatch.Options{
 		Path: watchPath,
 		Callback: func(path string) {
@@ -138,10 +153,18 @@ func (c *STDServerConfig) certificateUpdated(path string) error {
 		if err != nil {
 			return E.Cause(err, "reload key pair")
 		}
-		c.config.Certificates = []tls.Certificate{keyPair}
+		c.access.Lock()
+		config := c.config.Clone()
+		config.Certificates = []tls.Certificate{keyPair}
+		c.config = config
+		c.access.Unlock()
 		c.logger.Info("reloaded TLS certificate")
 	} else if path == c.echKeyPath {
-		err := reloadECHKeys(c.echKeyPath, c.config)
+		echKey, err := os.ReadFile(c.echKeyPath)
+		if err != nil {
+			return E.Cause(err, "reload ECH keys from ", c.echKeyPath)
+		}
+		err = c.setECHServerConfig(echKey)
 		if err != nil {
 			return err
 		}
@@ -160,7 +183,7 @@ func (c *STDServerConfig) Close() error {
 	return nil
 }
 
-func NewSTDServer(ctx context.Context, logger log.Logger, options option.InboundTLSOptions) (ServerConfig, error) {
+func NewSTDServer(ctx context.Context, logger log.ContextLogger, options option.InboundTLSOptions) (ServerConfig, error) {
 	if !options.Enabled {
 		return nil, nil
 	}
@@ -262,7 +285,7 @@ func NewSTDServer(ctx context.Context, logger log.Logger, options option.Inbound
 			return nil, err
 		}
 	}
-	return &STDServerConfig{
+	serverConfig := &STDServerConfig{
 		config:          tlsConfig,
 		logger:          logger,
 		acmeService:     acmeService,
@@ -271,5 +294,23 @@ func NewSTDServer(ctx context.Context, logger log.Logger, options option.Inbound
 		certificatePath: options.CertificatePath,
 		keyPath:         options.KeyPath,
 		echKeyPath:      echKeyPath,
-	}, nil
+	}
+	serverConfig.config.GetConfigForClient = func(info *tls.ClientHelloInfo) (*tls.Config, error) {
+		serverConfig.access.Lock()
+		defer serverConfig.access.Unlock()
+		return serverConfig.config, nil
+	}
+	var config ServerConfig = serverConfig
+	if options.KernelTx || options.KernelRx {
+		if !C.IsLinux {
+			return nil, E.New("kTLS is only supported on Linux")
+		}
+		config = &KTlSServerConfig{
+			ServerConfig: config,
+			logger:       logger,
+			kernelTx:     options.KernelTx,
+			kernelRx:     options.KernelRx,
+		}
+	}
+	return config, nil
 }

common/tls/time_wrapper.go

@@ -11,10 +11,13 @@ type TimeServiceWrapper struct {
 }
 
 func (w *TimeServiceWrapper) TimeFunc() func() time.Time {
-	if w.TimeService == nil {
-		return nil
+	return func() time.Time {
+		if w.TimeService != nil {
+			return w.TimeService.TimeFunc()()
+		} else {
+			return time.Now()
+		}
 	}
-	return w.TimeService.TimeFunc()
 }
 
 func (w *TimeServiceWrapper) Upstream() any {

common/tls/utls_client.go

@@ -14,8 +14,11 @@ import (
 
 	"github.com/sagernet/sing-box/adapter"
 	"github.com/sagernet/sing-box/common/tlsfragment"
+	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing/common"
 	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
 	"github.com/sagernet/sing/common/ntp"
 
 	utls "github.com/metacubex/utls"
@@ -50,7 +53,7 @@ func (c *UTLSClientConfig) SetNextProtos(nextProto []string) {
 	c.config.NextProtos = nextProto
 }
 
-func (c *UTLSClientConfig) Config() (*STDConfig, error) {
+func (c *UTLSClientConfig) STDConfig() (*STDConfig, error) {
 	return nil, E.New("unsupported usage for uTLS")
 }
 
@@ -106,6 +109,14 @@ func (c *utlsConnWrapper) Upstream() any {
 	return c.UConn
 }
 
+func (c *utlsConnWrapper) ReaderReplaceable() bool {
+	return true
+}
+
+func (c *utlsConnWrapper) WriterReplaceable() bool {
+	return true
+}
+
 type utlsALPNWrapper struct {
 	utlsConnWrapper
 	nextProtocols []string
@@ -131,7 +142,7 @@ func (c *utlsALPNWrapper) HandshakeContext(ctx context.Context) error {
 	return c.UConn.HandshakeContext(ctx)
 }
 
-func NewUTLSClient(ctx context.Context, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
+func NewUTLSClient(ctx context.Context, logger logger.ContextLogger, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
 	var serverName string
 	if options.ServerName != "" {
 		serverName = options.ServerName
@@ -145,11 +156,16 @@ func NewUTLSClient(ctx context.Context, serverAddress string, options option.Out
 	var tlsConfig utls.Config
 	tlsConfig.Time = ntp.TimeFuncFromContext(ctx)
 	tlsConfig.RootCAs = adapter.RootPoolFromContext(ctx)
-	tlsConfig.ServerName = serverName
+	if !options.DisableSNI {
+		tlsConfig.ServerName = serverName
+	}
 	if options.Insecure {
 		tlsConfig.InsecureSkipVerify = options.Insecure
 	} else if options.DisableSNI {
-		return nil, E.New("disable_sni is unsupported in uTLS")
+		if options.Reality != nil && options.Reality.Enabled {
+			return nil, E.New("disable_sni is unsupported in reality")
+		}
+		tlsConfig.InsecureServerNameToVerify = serverName
 	}
 	if len(options.ALPN) > 0 {
 		tlsConfig.NextProtos = options.ALPN
@@ -201,15 +217,28 @@ func NewUTLSClient(ctx context.Context, serverAddress string, options option.Out
 	if err != nil {
 		return nil, err
 	}
-	uConfig := &UTLSClientConfig{ctx, &tlsConfig, id, options.Fragment, time.Duration(options.FragmentFallbackDelay), options.RecordFragment}
+	var config Config = &UTLSClientConfig{ctx, &tlsConfig, id, options.Fragment, time.Duration(options.FragmentFallbackDelay), options.RecordFragment}
 	if options.ECH != nil && options.ECH.Enabled {
 		if options.Reality != nil && options.Reality.Enabled {
 			return nil, E.New("Reality is conflict with ECH")
 		}
-		return parseECHClientConfig(ctx, uConfig, options)
-	} else {
-		return uConfig, nil
+		config, err = parseECHClientConfig(ctx, config.(ECHCapableConfig), options)
+		if err != nil {
+			return nil, err
+		}
 	}
+	if (options.KernelRx || options.KernelTx) && !common.PtrValueOrDefault(options.Reality).Enabled {
+		if !C.IsLinux {
+			return nil, E.New("kTLS is only supported on Linux")
+		}
+		config = &KTLSClientConfig{
+			Config:   config,
+			logger:   logger,
+			kernelTx: options.KernelTx,
+			kernelRx: options.KernelRx,
+		}
+	}
+	return config, nil
 }
 
 var (

common/tls/utls_stub.go

@@ -8,13 +8,14 @@ import (
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
 	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
 )
 
-func NewUTLSClient(ctx context.Context, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
+func NewUTLSClient(ctx context.Context, logger logger.ContextLogger, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
 	return nil, E.New(`uTLS is not included in this build, rebuild with -tags with_utls`)
 }
 
-func NewRealityClient(ctx context.Context, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
+func NewRealityClient(ctx context.Context, logger logger.ContextLogger, serverAddress string, options option.OutboundTLSOptions) (Config, error) {
 	return nil, E.New(`uTLS, which is required by reality is not included in this build, rebuild with -tags with_utls`)
 }
 

common/tlsfragment/conn.go

@@ -45,7 +45,7 @@ func (c *Conn) Write(b []byte) (n int, err error) {
 		defer func() {
 			c.firstPacketWritten = true
 		}()
-		serverName := indexTLSServerName(b)
+		serverName := IndexTLSServerName(b)
 		if serverName != nil {
 			if c.splitPacket {
 				if c.tcpConn != nil {
@@ -109,6 +109,9 @@ func (c *Conn) Write(b []byte) (n int, err error) {
 						if err != nil {
 							return
 						}
+						if i != len(splitIndexes) {
+							time.Sleep(c.fallbackDelay)
+						}
 					}
 				}
 			}

common/tlsfragment/index.go

@@ -22,13 +22,13 @@ const (
 	tls13                   uint16 = 0x0304
 )
 
-type myServerName struct {
+type MyServerName struct {
 	Index      int
 	Length     int
 	ServerName string
 }
 
-func indexTLSServerName(payload []byte) *myServerName {
+func IndexTLSServerName(payload []byte) *MyServerName {
 	if len(payload) < recordLayerHeaderLen || payload[0] != contentType {
 		return nil
 	}
@@ -36,47 +36,48 @@ func indexTLSServerName(payload []byte) *myServerName {
 	if len(payload) < recordLayerHeaderLen+int(segmentLen) {
 		return nil
 	}
-	serverName := indexTLSServerNameFromHandshake(payload[recordLayerHeaderLen : recordLayerHeaderLen+int(segmentLen)])
+	serverName := indexTLSServerNameFromHandshake(payload[recordLayerHeaderLen:])
 	if serverName == nil {
 		return nil
 	}
-	serverName.Length += recordLayerHeaderLen
+	serverName.Index += recordLayerHeaderLen
 	return serverName
 }
 
-func indexTLSServerNameFromHandshake(hs []byte) *myServerName {
-	if len(hs) < handshakeHeaderLen+randomDataLen+sessionIDHeaderLen {
+func indexTLSServerNameFromHandshake(handshake []byte) *MyServerName {
+	if len(handshake) < handshakeHeaderLen+randomDataLen+sessionIDHeaderLen {
 		return nil
 	}
-	if hs[0] != handshakeType {
+	if handshake[0] != handshakeType {
 		return nil
 	}
-	handshakeLen := uint32(hs[1])<<16 | uint32(hs[2])<<8 | uint32(hs[3])
-	if len(hs[4:]) != int(handshakeLen) {
+	handshakeLen := uint32(handshake[1])<<16 | uint32(handshake[2])<<8 | uint32(handshake[3])
+	if len(handshake[4:]) != int(handshakeLen) {
 		return nil
 	}
-	tlsVersion := uint16(hs[4])<<8 | uint16(hs[5])
+	tlsVersion := uint16(handshake[4])<<8 | uint16(handshake[5])
 	if tlsVersion&tlsVersionBitmask != 0x0300 && tlsVersion != tls13 {
 		return nil
 	}
-	sessionIDLen := hs[38]
-	if len(hs) < handshakeHeaderLen+randomDataLen+sessionIDHeaderLen+int(sessionIDLen) {
+	sessionIDLen := handshake[38]
+	currentIndex := handshakeHeaderLen + randomDataLen + sessionIDHeaderLen + int(sessionIDLen)
+	if len(handshake) < currentIndex {
 		return nil
 	}
-	cs := hs[handshakeHeaderLen+randomDataLen+sessionIDHeaderLen+int(sessionIDLen):]
-	if len(cs) < cipherSuiteHeaderLen {
+	cipherSuites := handshake[currentIndex:]
+	if len(cipherSuites) < cipherSuiteHeaderLen {
 		return nil
 	}
-	csLen := uint16(cs[0])<<8 | uint16(cs[1])
-	if len(cs) < cipherSuiteHeaderLen+int(csLen)+compressMethodHeaderLen {
+	csLen := uint16(cipherSuites[0])<<8 | uint16(cipherSuites[1])
+	if len(cipherSuites) < cipherSuiteHeaderLen+int(csLen)+compressMethodHeaderLen {
 		return nil
 	}
-	compressMethodLen := uint16(cs[cipherSuiteHeaderLen+int(csLen)])
-	if len(cs) < cipherSuiteHeaderLen+int(csLen)+compressMethodHeaderLen+int(compressMethodLen) {
+	compressMethodLen := uint16(cipherSuites[cipherSuiteHeaderLen+int(csLen)])
+	currentIndex += cipherSuiteHeaderLen + int(csLen) + compressMethodHeaderLen + int(compressMethodLen)
+	if len(handshake) < currentIndex {
 		return nil
 	}
-	currentIndex := cipherSuiteHeaderLen + int(csLen) + compressMethodHeaderLen + int(compressMethodLen)
-	serverName := indexTLSServerNameFromExtensions(cs[currentIndex:])
+	serverName := indexTLSServerNameFromExtensions(handshake[currentIndex:])
 	if serverName == nil {
 		return nil
 	}
@@ -84,7 +85,7 @@ func indexTLSServerNameFromHandshake(hs []byte) *myServerName {
 	return serverName
 }
 
-func indexTLSServerNameFromExtensions(exs []byte) *myServerName {
+func indexTLSServerNameFromExtensions(exs []byte) *MyServerName {
 	if len(exs) == 0 {
 		return nil
 	}
@@ -118,7 +119,8 @@ func indexTLSServerNameFromExtensions(exs []byte) *myServerName {
 			}
 			sniLen := uint16(sex[3])<<8 | uint16(sex[4])
 			sex = sex[sniExtensionHeaderLen:]
-			return &myServerName{
+
+			return &MyServerName{
 				Index:      currentIndex + extensionHeaderLen + sniExtensionHeaderLen,
 				Length:     int(sniLen),
 				ServerName: string(sex),

common/tlsfragment/index_test.go

@@ -0,0 +1,20 @@
+package tf_test
+
+import (
+	"encoding/hex"
+	"testing"
+
+	"github.com/sagernet/sing-box/common/tlsfragment"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestIndexTLSServerName(t *testing.T) {
+	t.Parallel()
+	payload, err := hex.DecodeString("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")
+	require.NoError(t, err)
+	serverName := tf.IndexTLSServerName(payload)
+	require.NotNil(t, serverName)
+	require.Equal(t, serverName.ServerName, string(payload[serverName.Index:serverName.Index+serverName.Length]))
+	require.Equal(t, "github.com", serverName.ServerName)
+}

common/tlsfragment/wait_stub.go

@@ -9,6 +9,10 @@ import (
 )
 
 func writeAndWaitAck(ctx context.Context, conn *net.TCPConn, payload []byte, fallbackDelay time.Duration) error {
+	_, err := conn.Write(payload)
+	if err != nil {
+		return err
+	}
 	time.Sleep(fallbackDelay)
 	return nil
 }

common/tlsfragment/wait_windows.go

@@ -16,6 +16,9 @@ func writeAndWaitAck(ctx context.Context, conn *net.TCPConn, payload []byte, fal
 	err := winiphlpapi.WriteAndWaitAck(ctx, conn, payload)
 	if err != nil {
 		if errors.Is(err, windows.ERROR_ACCESS_DENIED) {
+			if _, err := conn.Write(payload); err != nil {
+				return err
+			}
 			time.Sleep(fallbackDelay)
 			return nil
 		}

common/urltest/urltest.go

@@ -11,7 +11,6 @@ import (
 
 	"github.com/sagernet/sing-box/adapter"
 	C "github.com/sagernet/sing-box/constant"
-	"github.com/sagernet/sing/common"
 	M "github.com/sagernet/sing/common/metadata"
 	N "github.com/sagernet/sing/common/network"
 	"github.com/sagernet/sing/common/ntp"
@@ -47,15 +46,15 @@ func (s *HistoryStorage) LoadURLTestHistory(tag string) *adapter.URLTestHistory
 func (s *HistoryStorage) DeleteURLTestHistory(tag string) {
 	s.access.Lock()
 	delete(s.delayHistory, tag)
-	s.access.Unlock()
 	s.notifyUpdated()
+	s.access.Unlock()
 }
 
 func (s *HistoryStorage) StoreURLTestHistory(tag string, history *adapter.URLTestHistory) {
 	s.access.Lock()
 	s.delayHistory[tag] = history
-	s.access.Unlock()
 	s.notifyUpdated()
+	s.access.Unlock()
 }
 
 func (s *HistoryStorage) notifyUpdated() {
@@ -69,6 +68,8 @@ func (s *HistoryStorage) notifyUpdated() {
 }
 
 func (s *HistoryStorage) Close() error {
+	s.access.Lock()
+	defer s.access.Unlock()
 	s.updateHook = nil
 	return nil
 }
@@ -98,7 +99,7 @@ func URLTest(ctx context.Context, link string, detour N.Dialer) (t uint16, err e
 		return
 	}
 	defer instance.Close()
-	if earlyConn, isEarlyConn := common.Cast[N.EarlyConn](instance); isEarlyConn && earlyConn.NeedHandshake() {
+	if N.NeedHandshakeForWrite(instance) {
 		start = time.Now()
 	}
 	req, err := http.NewRequest(http.MethodHead, link, nil)

constant/rule.go

@@ -22,7 +22,8 @@ const (
 	RuleSetVersion1 = 1 + iota
 	RuleSetVersion2
 	RuleSetVersion3
-	RuleSetVersionCurrent = RuleSetVersion3
+	RuleSetVersion4
+	RuleSetVersionCurrent = RuleSetVersion4
 )
 
 const (
@@ -39,4 +40,5 @@ const (
 const (
 	RuleActionRejectMethodDefault = "default"
 	RuleActionRejectMethodDrop    = "drop"
+	RuleActionRejectMethodReply   = "reply"
 )

constant/timeout.go

@@ -9,7 +9,6 @@ const (
 	TCPTimeout                 = 15 * time.Second
 	ReadPayloadTimeout         = 300 * time.Millisecond
 	DNSTimeout                 = 10 * time.Second
-	DirectDNSTimeout           = 5 * time.Second
 	UDPTimeout                 = 5 * time.Minute
 	DefaultURLTestInterval     = 3 * time.Minute
 	DefaultURLTestIdleTimeout  = 30 * time.Minute

dns/client.go

@@ -2,12 +2,14 @@ package dns
 
 import (
 	"context"
+	"errors"
 	"net"
 	"net/netip"
 	"strings"
 	"time"
 
 	"github.com/sagernet/sing-box/adapter"
+	"github.com/sagernet/sing-box/common/compatible"
 	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing/common"
 	E "github.com/sagernet/sing/common/exceptions"
@@ -17,7 +19,7 @@ import (
 	"github.com/sagernet/sing/contrab/freelru"
 	"github.com/sagernet/sing/contrab/maphash"
 
-	dns "github.com/miekg/dns"
+	"github.com/miekg/dns"
 )
 
 var (
@@ -30,18 +32,22 @@ var (
 var _ adapter.DNSClient = (*Client)(nil)
 
 type Client struct {
-	disableCache     bool
-	disableExpire    bool
-	independentCache bool
-	clientSubnet     netip.Prefix
-	rdrc             adapter.RDRCStore
-	initRDRCFunc     func() adapter.RDRCStore
-	logger           logger.ContextLogger
-	cache            freelru.Cache[dns.Question, *dns.Msg]
-	transportCache   freelru.Cache[transportCacheKey, *dns.Msg]
+	timeout            time.Duration
+	disableCache       bool
+	disableExpire      bool
+	independentCache   bool
+	clientSubnet       netip.Prefix
+	rdrc               adapter.RDRCStore
+	initRDRCFunc       func() adapter.RDRCStore
+	logger             logger.ContextLogger
+	cache              freelru.Cache[dns.Question, *dns.Msg]
+	cacheLock          compatible.Map[dns.Question, chan struct{}]
+	transportCache     freelru.Cache[transportCacheKey, *dns.Msg]
+	transportCacheLock compatible.Map[dns.Question, chan struct{}]
 }
 
 type ClientOptions struct {
+	Timeout          time.Duration
 	DisableCache     bool
 	DisableExpire    bool
 	IndependentCache bool
@@ -53,6 +59,7 @@ type ClientOptions struct {
 
 func NewClient(options ClientOptions) *Client {
 	client := &Client{
+		timeout:          options.Timeout,
 		disableCache:     options.DisableCache,
 		disableExpire:    options.DisableExpire,
 		independentCache: options.IndependentCache,
@@ -60,6 +67,9 @@ func NewClient(options ClientOptions) *Client {
 		initRDRCFunc:     options.RDRC,
 		logger:           options.Logger,
 	}
+	if client.timeout == 0 {
+		client.timeout = C.DNSTimeout
+	}
 	cacheCapacity := options.CacheCapacity
 	if cacheCapacity < 1024 {
 		cacheCapacity = 1024
@@ -90,17 +100,15 @@ func (c *Client) Exchange(ctx context.Context, transport adapter.DNSTransport, m
 		if c.logger != nil {
 			c.logger.WarnContext(ctx, "bad question size: ", len(message.Question))
 		}
-		responseMessage := dns.Msg{
-			MsgHdr: dns.MsgHdr{
-				Id:       message.Id,
-				Response: true,
-				Rcode:    dns.RcodeFormatError,
-			},
-			Question: message.Question,
-		}
-		return &responseMessage, nil
+		return FixedResponseStatus(message, dns.RcodeFormatError), nil
 	}
 	question := message.Question[0]
+	if question.Qtype == dns.TypeA && options.Strategy == C.DomainStrategyIPv6Only || question.Qtype == dns.TypeAAAA && options.Strategy == C.DomainStrategyIPv4Only {
+		if c.logger != nil {
+			c.logger.DebugContext(ctx, "strategy rejected")
+		}
+		return FixedResponseStatus(message, dns.RcodeSuccess), nil
+	}
 	clientSubnet := options.ClientSubnet
 	if !clientSubnet.IsValid() {
 		clientSubnet = c.clientSubnet
@@ -108,12 +116,38 @@ func (c *Client) Exchange(ctx context.Context, transport adapter.DNSTransport, m
 	if clientSubnet.IsValid() {
 		message = SetClientSubnet(message, clientSubnet)
 	}
+
 	isSimpleRequest := len(message.Question) == 1 &&
 		len(message.Ns) == 0 &&
-		len(message.Extra) == 0 &&
+		(len(message.Extra) == 0 || len(message.Extra) == 1 &&
+			message.Extra[0].Header().Rrtype == dns.TypeOPT &&
+			message.Extra[0].Header().Class > 0 &&
+			message.Extra[0].Header().Ttl == 0 &&
+			len(message.Extra[0].(*dns.OPT).Option) == 0) &&
 		!options.ClientSubnet.IsValid()
 	disableCache := !isSimpleRequest || c.disableCache || options.DisableCache
 	if !disableCache {
+		if c.cache != nil {
+			cond, loaded := c.cacheLock.LoadOrStore(question, make(chan struct{}))
+			if loaded {
+				<-cond
+			} else {
+				defer func() {
+					c.cacheLock.Delete(question)
+					close(cond)
+				}()
+			}
+		} else if c.transportCache != nil {
+			cond, loaded := c.transportCacheLock.LoadOrStore(question, make(chan struct{}))
+			if loaded {
+				<-cond
+			} else {
+				defer func() {
+					c.transportCacheLock.Delete(question)
+					close(cond)
+				}()
+			}
+		}
 		response, ttl := c.loadResponse(question, transport)
 		if response != nil {
 			logCachedResponse(c.logger, ctx, response, ttl)
@@ -121,45 +155,29 @@ func (c *Client) Exchange(ctx context.Context, transport adapter.DNSTransport, m
 			return response, nil
 		}
 	}
-	if question.Qtype == dns.TypeA && options.Strategy == C.DomainStrategyIPv6Only || question.Qtype == dns.TypeAAAA && options.Strategy == C.DomainStrategyIPv4Only {
-		responseMessage := dns.Msg{
-			MsgHdr: dns.MsgHdr{
-				Id:       message.Id,
-				Response: true,
-				Rcode:    dns.RcodeSuccess,
-			},
-			Question: []dns.Question{question},
-		}
-		if c.logger != nil {
-			c.logger.DebugContext(ctx, "strategy rejected")
-		}
-		return &responseMessage, nil
-	}
+
 	messageId := message.Id
 	contextTransport, clientSubnetLoaded := transportTagFromContext(ctx)
 	if clientSubnetLoaded && transport.Tag() == contextTransport {
 		return nil, E.New("DNS query loopback in transport[", contextTransport, "]")
 	}
 	ctx = contextWithTransportTag(ctx, transport.Tag())
-	if responseChecker != nil && c.rdrc != nil {
+	if !disableCache && responseChecker != nil && c.rdrc != nil {
 		rejected := c.rdrc.LoadRDRC(transport.Tag(), question.Name, question.Qtype)
 		if rejected {
 			return nil, ErrResponseRejectedCached
 		}
 	}
-	timeout := options.Timeout
-	if timeout == 0 {
-		if transport.HasDetour() {
-			timeout = C.DNSTimeout
-		} else {
-			timeout = C.DirectDNSTimeout
-		}
-	}
-	ctx, cancel := context.WithTimeout(ctx, timeout)
+	ctx, cancel := context.WithTimeout(ctx, c.timeout)
 	response, err := transport.Exchange(ctx, message)
 	cancel()
 	if err != nil {
-		return nil, err
+		var rcodeError RcodeError
+		if errors.As(err, &rcodeError) {
+			response = FixedResponseStatus(message, int(rcodeError))
+		} else {
+			return nil, err
+		}
 	}
 	/*if question.Qtype == dns.TypeA || question.Qtype == dns.TypeAAAA {
 		validResponse := response
@@ -196,10 +214,17 @@ func (c *Client) Exchange(ctx context.Context, transport adapter.DNSTransport, m
 			response.Answer = append(response.Answer, validResponse.Answer...)
 		}
 	}*/
+	disableCache = disableCache || response.Rcode != dns.RcodeSuccess || len(response.Answer) == 0
 	if responseChecker != nil {
-		addr, addrErr := MessageToAddresses(response)
-		if addrErr != nil || !responseChecker(addr) {
-			if c.rdrc != nil {
+		var rejected bool
+		// TODO: add accept_any rule and support to check response instead of addresses
+		if response.Rcode != dns.RcodeSuccess || len(response.Answer) == 0 {
+			rejected = true
+		} else {
+			rejected = !responseChecker(MessageToAddresses(response))
+		}
+		if rejected {
+			if !disableCache && c.rdrc != nil {
 				c.rdrc.SaveRDRCAsync(transport.Tag(), question.Name, question.Qtype, c.logger)
 			}
 			logRejectedResponse(c.logger, ctx, response)
@@ -256,7 +281,7 @@ func (c *Client) Exchange(ctx context.Context, transport adapter.DNSTransport, m
 		}
 	}
 	logExchangedResponse(c.logger, ctx, response, timeToLive)
-	return response, err
+	return response, nil
 }
 
 func (c *Client) Lookup(ctx context.Context, transport adapter.DNSTransport, domain string, options adapter.DNSQueryOptions, responseChecker func(responseAddrs []netip.Addr) bool) ([]netip.Addr, error) {
@@ -302,8 +327,7 @@ func (c *Client) Lookup(ctx context.Context, transport adapter.DNSTransport, dom
 func (c *Client) ClearCache() {
 	if c.cache != nil {
 		c.cache.Purge()
-	}
-	if c.transportCache != nil {
+	} else if c.transportCache != nil {
 		c.transportCache.Purge()
 	}
 }
@@ -317,36 +341,36 @@ func (c *Client) LookupCache(domain string, strategy C.DomainStrategy) ([]netip.
 	}
 	dnsName := dns.Fqdn(domain)
 	if strategy == C.DomainStrategyIPv4Only {
-		response, err := c.questionCache(dns.Question{
+		addresses, err := c.questionCache(dns.Question{
 			Name:   dnsName,
 			Qtype:  dns.TypeA,
 			Qclass: dns.ClassINET,
 		}, nil)
 		if err != ErrNotCached {
-			return response, true
+			return addresses, true
 		}
 	} else if strategy == C.DomainStrategyIPv6Only {
-		response, err := c.questionCache(dns.Question{
+		addresses, err := c.questionCache(dns.Question{
 			Name:   dnsName,
 			Qtype:  dns.TypeAAAA,
 			Qclass: dns.ClassINET,
 		}, nil)
 		if err != ErrNotCached {
-			return response, true
+			return addresses, true
 		}
 	} else {
-		response4, _ := c.questionCache(dns.Question{
+		response4, _ := c.loadResponse(dns.Question{
 			Name:   dnsName,
 			Qtype:  dns.TypeA,
 			Qclass: dns.ClassINET,
 		}, nil)
-		response6, _ := c.questionCache(dns.Question{
+		response6, _ := c.loadResponse(dns.Question{
 			Name:   dnsName,
 			Qtype:  dns.TypeAAAA,
 			Qclass: dns.ClassINET,
 		}, nil)
-		if len(response4) > 0 || len(response6) > 0 {
-			return sortAddresses(response4, response6, strategy), true
+		if response4 != nil || response6 != nil {
+			return sortAddresses(MessageToAddresses(response4), MessageToAddresses(response6), strategy), true
 		}
 	}
 	return nil, false
@@ -387,15 +411,15 @@ func (c *Client) storeCache(transport adapter.DNSTransport, question dns.Questio
 				transportTag: transport.Tag(),
 			}, message)
 		}
-		return
-	}
-	if !c.independentCache {
-		c.cache.AddWithLifetime(question, message, time.Second*time.Duration(timeToLive))
 	} else {
-		c.transportCache.AddWithLifetime(transportCacheKey{
-			Question:     question,
-			transportTag: transport.Tag(),
-		}, message, time.Second*time.Duration(timeToLive))
+		if !c.independentCache {
+			c.cache.AddWithLifetime(question, message, time.Second*time.Duration(timeToLive))
+		} else {
+			c.transportCache.AddWithLifetime(transportCacheKey{
+				Question:     question,
+				transportTag: transport.Tag(),
+			}, message, time.Second*time.Duration(timeToLive))
+		}
 	}
 }
 
@@ -422,7 +446,10 @@ func (c *Client) lookupToExchange(ctx context.Context, transport adapter.DNSTran
 	if err != nil {
 		return nil, err
 	}
-	return MessageToAddresses(response)
+	if response.Rcode != dns.RcodeSuccess {
+		return nil, RcodeError(response.Rcode)
+	}
+	return MessageToAddresses(response), nil
 }
 
 func (c *Client) questionCache(question dns.Question, transport adapter.DNSTransport) ([]netip.Addr, error) {
@@ -430,7 +457,10 @@ func (c *Client) questionCache(question dns.Question, transport adapter.DNSTrans
 	if response == nil {
 		return nil, ErrNotCached
 	}
-	return MessageToAddresses(response)
+	if response.Rcode != dns.RcodeSuccess {
+		return nil, RcodeError(response.Rcode)
+	}
+	return MessageToAddresses(response), nil
 }
 
 func (c *Client) loadResponse(question dns.Question, transport adapter.DNSTransport) (*dns.Msg, int) {
@@ -507,9 +537,9 @@ func (c *Client) loadResponse(question dns.Question, transport adapter.DNSTransp
 	}
 }
 
-func MessageToAddresses(response *dns.Msg) ([]netip.Addr, error) {
-	if response.Rcode != dns.RcodeSuccess {
-		return nil, RcodeError(response.Rcode)
+func MessageToAddresses(response *dns.Msg) []netip.Addr {
+	if response == nil || response.Rcode != dns.RcodeSuccess {
+		return nil
 	}
 	addresses := make([]netip.Addr, 0, len(response.Answer))
 	for _, rawAnswer := range response.Answer {
@@ -526,7 +556,7 @@ func MessageToAddresses(response *dns.Msg) ([]netip.Addr, error) {
 			}
 		}
 	}
-	return addresses, nil
+	return addresses
 }
 
 func wrapError(err error) error {
@@ -555,9 +585,12 @@ func transportTagFromContext(ctx context.Context) (string, bool) {
 func FixedResponseStatus(message *dns.Msg, rcode int) *dns.Msg {
 	return &dns.Msg{
 		MsgHdr: dns.MsgHdr{
-			Id:       message.Id,
-			Rcode:    rcode,
-			Response: true,
+			Id:                 message.Id,
+			Response:           true,
+			Authoritative:      true,
+			RecursionDesired:   true,
+			RecursionAvailable: true,
+			Rcode:              rcode,
 		},
 		Question: message.Question,
 	}

dns/rcode.go

@@ -5,6 +5,7 @@ import (
 )
 
 const (
+	RcodeSuccess     RcodeError = mDNS.RcodeSuccess
 	RcodeFormatError RcodeError = mDNS.RcodeFormatError
 	RcodeNameError   RcodeError = mDNS.RcodeNameError
 	RcodeRefused     RcodeError = mDNS.RcodeRefused

dns/router.go

@@ -158,9 +158,6 @@ func (r *Router) matchDNS(ctx context.Context, allowFakeIP bool, ruleIndex int,
 				if action.Strategy != C.DomainStrategyAsIS {
 					options.Strategy = action.Strategy
 				}
-				if action.Timeout > 0 {
-					options.Timeout = action.Timeout
-				}
 				if isFakeIP || action.DisableCache {
 					options.DisableCache = true
 				}
@@ -183,9 +180,6 @@ func (r *Router) matchDNS(ctx context.Context, allowFakeIP bool, ruleIndex int,
 				if action.Strategy != C.DomainStrategyAsIS {
 					options.Strategy = action.Strategy
 				}
-				if action.Timeout > 0 {
-					options.Timeout = action.Timeout
-				}
 				if action.DisableCache {
 					options.DisableCache = true
 				}
@@ -299,12 +293,7 @@ func (r *Router) Exchange(ctx context.Context, message *mDNS.Msg, options adapte
 					} else if errors.Is(err, ErrResponseRejected) {
 						rejected = true
 						r.logger.DebugContext(ctx, E.Cause(err, "response rejected for ", FormatQuestion(message.Question[0].String())))
-						/*} else if responseCheck!= nil && errors.Is(err, RcodeError(mDNS.RcodeNameError)) {
-						rejected = true
-						r.logger.DebugContext(ctx, E.Cause(err, "response rejected for ", FormatQuestion(message.Question[0].String())))
-						*/
 					} else if len(message.Question) > 0 {
-						rejected = true
 						r.logger.ErrorContext(ctx, E.Cause(err, "exchange failed for ", FormatQuestion(message.Question[0].String())))
 					} else {
 						r.logger.ErrorContext(ctx, E.Cause(err, "exchange failed for <empty query>"))

dns/transport/dhcp/dhcp.go

@@ -2,17 +2,18 @@ package dhcp
 
 import (
 	"context"
+	"errors"
+	"io"
 	"net"
 	"runtime"
 	"strings"
 	"sync"
+	"syscall"
 	"time"
 
 	"github.com/sagernet/sing-box/adapter"
-	"github.com/sagernet/sing-box/common/dialer"
 	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/dns"
-	"github.com/sagernet/sing-box/dns/transport"
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
 	"github.com/sagernet/sing-tun"
@@ -29,6 +30,7 @@ import (
 
 	"github.com/insomniacslk/dhcp/dhcpv4"
 	mDNS "github.com/miekg/dns"
+	"golang.org/x/exp/slices"
 )
 
 func RegisterTransport(registry *dns.TransportRegistry) {
@@ -41,14 +43,16 @@ type Transport struct {
 	dns.TransportAdapter
 	ctx               context.Context
 	dialer            N.Dialer
-	hasDetour         bool
 	logger            logger.ContextLogger
 	networkManager    adapter.NetworkManager
 	interfaceName     string
 	interfaceCallback *list.Element[tun.DefaultInterfaceUpdateCallback]
-	transports        []adapter.DNSTransport
-	updateAccess      sync.Mutex
+	transportLock     sync.RWMutex
 	updatedAt         time.Time
+	servers           []M.Socksaddr
+	search            []string
+	ndots             int
+	attempts          int
 }
 
 func NewTransport(ctx context.Context, logger log.ContextLogger, tag string, options option.DHCPDNSServerOptions) (adapter.DNSTransport, error) {
@@ -60,59 +64,88 @@ func NewTransport(ctx context.Context, logger log.ContextLogger, tag string, opt
 		TransportAdapter: dns.NewTransportAdapterWithLocalOptions(C.DNSTypeDHCP, tag, options.LocalDNSServerOptions),
 		ctx:              ctx,
 		dialer:           transportDialer,
-		hasDetour:        options.Detour != "",
 		logger:           logger,
 		networkManager:   service.FromContext[adapter.NetworkManager](ctx),
 		interfaceName:    options.Interface,
+		ndots:            1,
+		attempts:         2,
 	}, nil
 }
 
+func NewRawTransport(transportAdapter dns.TransportAdapter, ctx context.Context, dialer N.Dialer, logger log.ContextLogger) *Transport {
+	return &Transport{
+		TransportAdapter: transportAdapter,
+		ctx:              ctx,
+		dialer:           dialer,
+		logger:           logger,
+		networkManager:   service.FromContext[adapter.NetworkManager](ctx),
+		ndots:            1,
+		attempts:         2,
+	}
+}
+
 func (t *Transport) Start(stage adapter.StartStage) error {
 	if stage != adapter.StartStateStart {
 		return nil
 	}
-	err := t.fetchServers()
-	if err != nil {
-		return err
-	}
 	if t.interfaceName == "" {
 		t.interfaceCallback = t.networkManager.InterfaceMonitor().RegisterCallback(t.interfaceUpdated)
 	}
+	go func() {
+		_, err := t.Fetch()
+		if err != nil {
+			t.logger.Error(E.Cause(err, "fetch DNS servers"))
+		}
+	}()
 	return nil
 }
 
 func (t *Transport) Close() error {
-	for _, transport := range t.transports {
-		transport.Close()
-	}
 	if t.interfaceCallback != nil {
 		t.networkManager.InterfaceMonitor().UnregisterCallback(t.interfaceCallback)
 	}
 	return nil
 }
 
-func (t *Transport) HasDetour() bool {
-	return t.hasDetour
-}
-
 func (t *Transport) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.Msg, error) {
-	err := t.fetchServers()
+	servers, err := t.Fetch()
 	if err != nil {
 		return nil, err
 	}
-
-	if len(t.transports) == 0 {
+	if len(servers) == 0 {
 		return nil, E.New("dhcp: empty DNS servers from response")
 	}
+	return t.Exchange0(ctx, message, servers)
+}
 
-	var response *mDNS.Msg
-	for _, transport := range t.transports {
-		response, err = transport.Exchange(ctx, message)
-		if err == nil {
-			return response, nil
-		}
+func (t *Transport) Exchange0(ctx context.Context, message *mDNS.Msg, servers []M.Socksaddr) (*mDNS.Msg, error) {
+	question := message.Question[0]
+	domain := dns.FqdnToDomain(question.Name)
+	if len(servers) == 1 || !(message.Question[0].Qtype == mDNS.TypeA || message.Question[0].Qtype == mDNS.TypeAAAA) {
+		return t.exchangeSingleRequest(ctx, servers, message, domain)
+	} else {
+		return t.exchangeParallel(ctx, servers, message, domain)
 	}
-	return nil, err
+}
+
+func (t *Transport) Fetch() ([]M.Socksaddr, error) {
+	t.transportLock.RLock()
+	updatedAt := t.updatedAt
+	servers := t.servers
+	t.transportLock.RUnlock()
+	if time.Since(updatedAt) < C.DHCPTTL {
+		return servers, nil
+	}
+	t.transportLock.Lock()
+	defer t.transportLock.Unlock()
+	if time.Since(t.updatedAt) < C.DHCPTTL {
+		return t.servers, nil
+	}
+	err := t.updateServers()
+	if err != nil {
+		return nil, err
+	}
+	return t.servers, nil
 }
 
 func (t *Transport) fetchInterface() (*control.Interface, error) {
@@ -130,18 +163,6 @@ func (t *Transport) fetchInterface() (*control.Interface, error) {
 	}
 }
 
-func (t *Transport) fetchServers() error {
-	if time.Since(t.updatedAt) < C.DHCPTTL {
-		return nil
-	}
-	t.updateAccess.Lock()
-	defer t.updateAccess.Unlock()
-	if time.Since(t.updatedAt) < C.DHCPTTL {
-		return nil
-	}
-	return t.updateServers()
-}
-
 func (t *Transport) updateServers() error {
 	iface, err := t.fetchInterface()
 	if err != nil {
@@ -154,7 +175,7 @@ func (t *Transport) updateServers() error {
 	cancel()
 	if err != nil {
 		return err
-	} else if len(t.transports) == 0 {
+	} else if len(t.servers) == 0 {
 		return E.New("dhcp: empty DNS servers response")
 	} else {
 		t.updatedAt = time.Now()
@@ -177,13 +198,27 @@ func (t *Transport) fetchServers0(ctx context.Context, iface *control.Interface)
 	if runtime.GOOS == "linux" || runtime.GOOS == "android" {
 		listenAddr = "255.255.255.255:68"
 	}
-	packetConn, err := listener.ListenPacket(t.ctx, "udp4", listenAddr)
+	var (
+		packetConn net.PacketConn
+		err        error
+	)
+	for i := 0; i < 5; i++ {
+		packetConn, err = listener.ListenPacket(t.ctx, "udp4", listenAddr)
+		if err == nil || !errors.Is(err, syscall.EADDRINUSE) {
+			break
+		}
+		time.Sleep(time.Second)
+	}
 	if err != nil {
 		return err
 	}
 	defer packetConn.Close()
 
-	discovery, err := dhcpv4.NewDiscovery(iface.HardwareAddr, dhcpv4.WithBroadcast(true), dhcpv4.WithRequestedOptions(dhcpv4.OptionDomainNameServer))
+	discovery, err := dhcpv4.NewDiscovery(iface.HardwareAddr, dhcpv4.WithBroadcast(true), dhcpv4.WithRequestedOptions(
+		dhcpv4.OptionDomainName,
+		dhcpv4.OptionDomainNameServer,
+		dhcpv4.OptionDNSDomainSearchList,
+	))
 	if err != nil {
 		return err
 	}
@@ -210,6 +245,9 @@ func (t *Transport) fetchServersResponse(iface *control.Interface, packetConn ne
 	for {
 		_, _, err := buffer.ReadPacketFrom(packetConn)
 		if err != nil {
+			if errors.Is(err, io.ErrShortBuffer) {
+				continue
+			}
 			return err
 		}
 
@@ -229,31 +267,23 @@ func (t *Transport) fetchServersResponse(iface *control.Interface, packetConn ne
 			continue
 		}
 
-		dns := dhcpPacket.DNS()
-		if len(dns) == 0 {
-			return nil
-		}
-		return t.recreateServers(iface, common.Map(dns, func(it net.IP) M.Socksaddr {
-			return M.SocksaddrFrom(M.AddrFromIP(it), 53)
-		}))
+		return t.recreateServers(iface, dhcpPacket)
 	}
 }
 
-func (t *Transport) recreateServers(iface *control.Interface, serverAddrs []M.Socksaddr) error {
-	if len(serverAddrs) > 0 {
-		t.logger.Info("dhcp: updated DNS servers from ", iface.Name, ": [", strings.Join(common.Map(serverAddrs, M.Socksaddr.String), ","), "]")
+func (t *Transport) recreateServers(iface *control.Interface, dhcpPacket *dhcpv4.DHCPv4) error {
+	searchList := dhcpPacket.DomainSearch()
+	if searchList != nil && len(searchList.Labels) > 0 {
+		t.search = searchList.Labels
+	} else if dhcpPacket.DomainName() != "" {
+		t.search = []string{dhcpPacket.DomainName()}
 	}
-	serverDialer := common.Must1(dialer.NewDefault(t.ctx, option.DialerOptions{
-		BindInterface:      iface.Name,
-		UDPFragmentDefault: true,
-	}))
-	var transports []adapter.DNSTransport
-	for _, serverAddr := range serverAddrs {
-		transports = append(transports, transport.NewUDPRaw(t.logger, t.TransportAdapter, serverDialer, serverAddr))
+	serverAddrs := common.Map(dhcpPacket.DNS(), func(it net.IP) M.Socksaddr {
+		return M.SocksaddrFrom(M.AddrFromIP(it), 53)
+	})
+	if len(serverAddrs) > 0 && !slices.Equal(t.servers, serverAddrs) {
+		t.logger.Info("dhcp: updated DNS servers from ", iface.Name, ": [", strings.Join(common.Map(serverAddrs, M.Socksaddr.String), ","), "], search: [", strings.Join(t.search, ","), "]")
 	}
-	for _, transport := range t.transports {
-		transport.Close()
-	}
-	t.transports = transports
+	t.servers = serverAddrs
 	return nil
 }

dns/transport/dhcp/dhcp_shared.go

@@ -0,0 +1,213 @@
+package dhcp
+
+import (
+	"context"
+	"errors"
+	"math/rand"
+	"strings"
+	"syscall"
+
+	"github.com/sagernet/sing-box/dns"
+	"github.com/sagernet/sing-box/dns/transport"
+	"github.com/sagernet/sing/common/buf"
+	E "github.com/sagernet/sing/common/exceptions"
+	M "github.com/sagernet/sing/common/metadata"
+	N "github.com/sagernet/sing/common/network"
+
+	mDNS "github.com/miekg/dns"
+)
+
+func (t *Transport) exchangeSingleRequest(ctx context.Context, servers []M.Socksaddr, message *mDNS.Msg, domain string) (*mDNS.Msg, error) {
+	var lastErr error
+	for _, fqdn := range t.nameList(domain) {
+		response, err := t.tryOneName(ctx, servers, fqdn, message)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+		return response, nil
+	}
+	return nil, lastErr
+}
+
+func (t *Transport) exchangeParallel(ctx context.Context, servers []M.Socksaddr, message *mDNS.Msg, domain string) (*mDNS.Msg, error) {
+	returned := make(chan struct{})
+	defer close(returned)
+	type queryResult struct {
+		response *mDNS.Msg
+		err      error
+	}
+	results := make(chan queryResult)
+	startRacer := func(ctx context.Context, fqdn string) {
+		response, err := t.tryOneName(ctx, servers, fqdn, message)
+		if err == nil {
+			if response.Rcode != mDNS.RcodeSuccess {
+				err = dns.RcodeError(response.Rcode)
+			} else if len(dns.MessageToAddresses(response)) == 0 {
+				err = dns.RcodeSuccess
+			}
+		}
+		select {
+		case results <- queryResult{response, err}:
+		case <-returned:
+		}
+	}
+	queryCtx, queryCancel := context.WithCancel(ctx)
+	defer queryCancel()
+	var nameCount int
+	for _, fqdn := range t.nameList(domain) {
+		nameCount++
+		go startRacer(queryCtx, fqdn)
+	}
+	var errors []error
+	for {
+		select {
+		case <-ctx.Done():
+			return nil, ctx.Err()
+		case result := <-results:
+			if result.err == nil {
+				return result.response, nil
+			}
+			errors = append(errors, result.err)
+			if len(errors) == nameCount {
+				return nil, E.Errors(errors...)
+			}
+		}
+	}
+}
+
+func (t *Transport) tryOneName(ctx context.Context, servers []M.Socksaddr, fqdn string, message *mDNS.Msg) (*mDNS.Msg, error) {
+	sLen := len(servers)
+	var lastErr error
+	for i := 0; i < t.attempts; i++ {
+		for j := 0; j < sLen; j++ {
+			server := servers[j]
+			question := message.Question[0]
+			question.Name = fqdn
+			response, err := t.exchangeOne(ctx, server, question)
+			if err != nil {
+				lastErr = err
+				continue
+			}
+			return response, nil
+		}
+	}
+	return nil, E.Cause(lastErr, fqdn)
+}
+
+func (t *Transport) exchangeOne(ctx context.Context, server M.Socksaddr, question mDNS.Question) (*mDNS.Msg, error) {
+	if server.Port == 0 {
+		server.Port = 53
+	}
+	request := &mDNS.Msg{
+		MsgHdr: mDNS.MsgHdr{
+			Id:                uint16(rand.Uint32()),
+			RecursionDesired:  true,
+			AuthenticatedData: true,
+		},
+		Question: []mDNS.Question{question},
+		Compress: true,
+	}
+	request.SetEdns0(buf.UDPBufferSize, false)
+	return t.exchangeUDP(ctx, server, request)
+}
+
+func (t *Transport) exchangeUDP(ctx context.Context, server M.Socksaddr, request *mDNS.Msg) (*mDNS.Msg, error) {
+	conn, err := t.dialer.DialContext(ctx, N.NetworkUDP, server)
+	if err != nil {
+		return nil, err
+	}
+	defer conn.Close()
+	if deadline, loaded := ctx.Deadline(); loaded && !deadline.IsZero() {
+		conn.SetDeadline(deadline)
+	}
+	buffer := buf.Get(buf.UDPBufferSize)
+	defer buf.Put(buffer)
+	rawMessage, err := request.PackBuffer(buffer)
+	if err != nil {
+		return nil, E.Cause(err, "pack request")
+	}
+	_, err = conn.Write(rawMessage)
+	if err != nil {
+		if errors.Is(err, syscall.EMSGSIZE) {
+			return t.exchangeTCP(ctx, server, request)
+		}
+		return nil, E.Cause(err, "write request")
+	}
+	n, err := conn.Read(buffer)
+	if err != nil {
+		if errors.Is(err, syscall.EMSGSIZE) {
+			return t.exchangeTCP(ctx, server, request)
+		}
+		return nil, E.Cause(err, "read response")
+	}
+	var response mDNS.Msg
+	err = response.Unpack(buffer[:n])
+	if err != nil {
+		return nil, E.Cause(err, "unpack response")
+	}
+	if response.Truncated {
+		return t.exchangeTCP(ctx, server, request)
+	}
+	return &response, nil
+}
+
+func (t *Transport) exchangeTCP(ctx context.Context, server M.Socksaddr, request *mDNS.Msg) (*mDNS.Msg, error) {
+	conn, err := t.dialer.DialContext(ctx, N.NetworkTCP, server)
+	if err != nil {
+		return nil, err
+	}
+	defer conn.Close()
+	if deadline, loaded := ctx.Deadline(); loaded && !deadline.IsZero() {
+		conn.SetDeadline(deadline)
+	}
+	err = transport.WriteMessage(conn, 0, request)
+	if err != nil {
+		return nil, err
+	}
+	return transport.ReadMessage(conn)
+}
+
+func (t *Transport) nameList(name string) []string {
+	l := len(name)
+	rooted := l > 0 && name[l-1] == '.'
+	if l > 254 || l == 254 && !rooted {
+		return nil
+	}
+
+	if rooted {
+		if avoidDNS(name) {
+			return nil
+		}
+		return []string{name}
+	}
+
+	hasNdots := strings.Count(name, ".") >= t.ndots
+	name += "."
+	// l++
+
+	names := make([]string, 0, 1+len(t.search))
+	if hasNdots && !avoidDNS(name) {
+		names = append(names, name)
+	}
+	for _, suffix := range t.search {
+		fqdn := name + suffix
+		if !avoidDNS(fqdn) && len(fqdn) <= 254 {
+			names = append(names, fqdn)
+		}
+	}
+	if !hasNdots && !avoidDNS(name) {
+		names = append(names, name)
+	}
+	return names
+}
+
+func avoidDNS(name string) bool {
+	if name == "" {
+		return true
+	}
+	if name[len(name)-1] == '.' {
+		name = name[:len(name)-1]
+	}
+	return strings.HasSuffix(name, ".onion")
+}

dns/transport/https.go

@@ -8,7 +8,6 @@ import (
 	"net"
 	"net/http"
 	"net/url"
-	"os"
 	"strconv"
 	"sync"
 	"time"
@@ -59,11 +58,11 @@ func NewHTTPS(ctx context.Context, logger log.ContextLogger, tag string, options
 	}
 	tlsOptions := common.PtrValueOrDefault(options.TLS)
 	tlsOptions.Enabled = true
-	tlsConfig, err := tls.NewClient(ctx, options.Server, tlsOptions)
+	tlsConfig, err := tls.NewClient(ctx, logger, options.Server, tlsOptions)
 	if err != nil {
 		return nil, err
 	}
-	if common.Error(tlsConfig.Config()) == nil && !common.Contains(tlsConfig.NextProtos(), http2.NextProtoTLS) {
+	if common.Error(tlsConfig.STDConfig()) == nil && !common.Contains(tlsConfig.NextProtos(), http2.NextProtoTLS) {
 		tlsConfig.SetNextProtos(append(tlsConfig.NextProtos(), http2.NextProtoTLS))
 	}
 	if !common.Contains(tlsConfig.NextProtos(), "http/1.1") {
@@ -178,7 +177,7 @@ func (t *HTTPSTransport) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS
 	startAt := time.Now()
 	response, err := t.exchange(ctx, message)
 	if err != nil {
-		if errors.Is(err, os.ErrDeadlineExceeded) {
+		if errors.Is(err, context.DeadlineExceeded) {
 			t.transportAccess.Lock()
 			defer t.transportAccess.Unlock()
 			if t.transportResetAt.After(startAt) {

dns/transport/local/local.go

@@ -1,10 +1,9 @@
+//go:build !darwin
+
 package local
 
 import (
 	"context"
-	"math/rand"
-	"net/netip"
-	"time"
 
 	"github.com/sagernet/sing-box/adapter"
 	C "github.com/sagernet/sing-box/constant"
@@ -12,21 +11,27 @@ import (
 	"github.com/sagernet/sing-box/dns/transport/hosts"
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
-	"github.com/sagernet/sing/common/buf"
 	E "github.com/sagernet/sing/common/exceptions"
-	M "github.com/sagernet/sing/common/metadata"
+	"github.com/sagernet/sing/common/logger"
 	N "github.com/sagernet/sing/common/network"
 
 	mDNS "github.com/miekg/dns"
 )
 
+func RegisterTransport(registry *dns.TransportRegistry) {
+	dns.RegisterTransport[option.LocalDNSServerOptions](registry, C.DNSTypeLocal, NewTransport)
+}
+
 var _ adapter.DNSTransport = (*Transport)(nil)
 
 type Transport struct {
 	dns.TransportAdapter
-	ctx    context.Context
-	hosts  *hosts.File
-	dialer N.Dialer
+	ctx      context.Context
+	logger   logger.ContextLogger
+	hosts    *hosts.File
+	dialer   N.Dialer
+	preferGo bool
+	resolved ResolvedResolver
 }
 
 func NewTransport(ctx context.Context, logger log.ContextLogger, tag string, options option.LocalDNSServerOptions) (adapter.DNSTransport, error) {
@@ -37,20 +42,45 @@ func NewTransport(ctx context.Context, logger log.ContextLogger, tag string, opt
 	return &Transport{
 		TransportAdapter: dns.NewTransportAdapterWithLocalOptions(C.DNSTypeLocal, tag, options),
 		ctx:              ctx,
+		logger:           logger,
 		hosts:            hosts.NewFile(hosts.DefaultPath),
 		dialer:           transportDialer,
+		preferGo:         options.PreferGo,
 	}, nil
 }
 
 func (t *Transport) Start(stage adapter.StartStage) error {
+	switch stage {
+	case adapter.StartStateInitialize:
+		if !t.preferGo {
+			resolvedResolver, err := NewResolvedResolver(t.ctx, t.logger)
+			if err == nil {
+				err = resolvedResolver.Start()
+				if err == nil {
+					t.resolved = resolvedResolver
+				} else {
+					t.logger.Warn(E.Cause(err, "initialize resolved resolver"))
+				}
+			}
+		}
+	}
 	return nil
 }
 
 func (t *Transport) Close() error {
+	if t.resolved != nil {
+		return t.resolved.Close()
+	}
 	return nil
 }
 
 func (t *Transport) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.Msg, error) {
+	if t.resolved != nil {
+		resolverObject := t.resolved.Object()
+		if resolverObject != nil {
+			return t.resolved.Exchange(resolverObject, ctx, message)
+		}
+	}
 	question := message.Question[0]
 	domain := dns.FqdnToDomain(question.Name)
 	if question.Qtype == mDNS.TypeA || question.Qtype == mDNS.TypeAAAA {
@@ -59,147 +89,5 @@ func (t *Transport) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.Msg,
 			return dns.FixedResponse(message.Id, question, addresses, C.DefaultDNSTTL), nil
 		}
 	}
-	systemConfig := getSystemDNSConfig(t.ctx)
-	if systemConfig.singleRequest || !(message.Question[0].Qtype == mDNS.TypeA || message.Question[0].Qtype == mDNS.TypeAAAA) {
-		return t.exchangeSingleRequest(ctx, systemConfig, message, domain)
-	} else {
-		return t.exchangeParallel(ctx, systemConfig, message, domain)
-	}
-}
-
-func (t *Transport) exchangeSingleRequest(ctx context.Context, systemConfig *dnsConfig, message *mDNS.Msg, domain string) (*mDNS.Msg, error) {
-	var lastErr error
-	for _, fqdn := range systemConfig.nameList(domain) {
-		response, err := t.tryOneName(ctx, systemConfig, fqdn, message)
-		if err != nil {
-			lastErr = err
-			continue
-		}
-		return response, nil
-	}
-	return nil, lastErr
-}
-
-func (t *Transport) exchangeParallel(ctx context.Context, systemConfig *dnsConfig, message *mDNS.Msg, domain string) (*mDNS.Msg, error) {
-	returned := make(chan struct{})
-	defer close(returned)
-	type queryResult struct {
-		response *mDNS.Msg
-		err      error
-	}
-	results := make(chan queryResult)
-	startRacer := func(ctx context.Context, fqdn string) {
-		response, err := t.tryOneName(ctx, systemConfig, fqdn, message)
-		if err == nil {
-			var addresses []netip.Addr
-			addresses, err = dns.MessageToAddresses(response)
-			if err == nil && len(addresses) == 0 {
-				err = E.New(fqdn, ": empty result")
-			}
-		}
-		select {
-		case results <- queryResult{response, err}:
-		case <-returned:
-		}
-	}
-	queryCtx, queryCancel := context.WithCancel(ctx)
-	defer queryCancel()
-	var nameCount int
-	for _, fqdn := range systemConfig.nameList(domain) {
-		nameCount++
-		go startRacer(queryCtx, fqdn)
-	}
-	var errors []error
-	for {
-		select {
-		case <-ctx.Done():
-			return nil, ctx.Err()
-		case result := <-results:
-			if result.err == nil {
-				return result.response, nil
-			}
-			errors = append(errors, result.err)
-			if len(errors) == nameCount {
-				return nil, E.Errors(errors...)
-			}
-		}
-	}
-}
-
-func (t *Transport) tryOneName(ctx context.Context, config *dnsConfig, fqdn string, message *mDNS.Msg) (*mDNS.Msg, error) {
-	serverOffset := config.serverOffset()
-	sLen := uint32(len(config.servers))
-	var lastErr error
-	for i := 0; i < config.attempts; i++ {
-		for j := uint32(0); j < sLen; j++ {
-			server := config.servers[(serverOffset+j)%sLen]
-			question := message.Question[0]
-			question.Name = fqdn
-			response, err := t.exchangeOne(ctx, M.ParseSocksaddr(server), question, config.timeout, config.useTCP, config.trustAD)
-			if err != nil {
-				lastErr = err
-				continue
-			}
-			return response, nil
-		}
-	}
-	return nil, E.Cause(lastErr, fqdn)
-}
-
-func (t *Transport) exchangeOne(ctx context.Context, server M.Socksaddr, question mDNS.Question, timeout time.Duration, useTCP, ad bool) (*mDNS.Msg, error) {
-	if server.Port == 0 {
-		server.Port = 53
-	}
-	var networks []string
-	if useTCP {
-		networks = []string{N.NetworkTCP}
-	} else {
-		networks = []string{N.NetworkUDP, N.NetworkTCP}
-	}
-	request := &mDNS.Msg{
-		MsgHdr: mDNS.MsgHdr{
-			Id:                uint16(rand.Uint32()),
-			RecursionDesired:  true,
-			AuthenticatedData: ad,
-		},
-		Question: []mDNS.Question{question},
-		Compress: true,
-	}
-	request.SetEdns0(maxDNSPacketSize, false)
-	buffer := buf.Get(buf.UDPBufferSize)
-	defer buf.Put(buffer)
-	for _, network := range networks {
-		ctx, cancel := context.WithDeadline(ctx, time.Now().Add(timeout))
-		defer cancel()
-		conn, err := t.dialer.DialContext(ctx, network, server)
-		if err != nil {
-			return nil, err
-		}
-		defer conn.Close()
-		if deadline, loaded := ctx.Deadline(); loaded && !deadline.IsZero() {
-			conn.SetDeadline(deadline)
-		}
-		rawMessage, err := request.PackBuffer(buffer)
-		if err != nil {
-			return nil, E.Cause(err, "pack request")
-		}
-		_, err = conn.Write(rawMessage)
-		if err != nil {
-			return nil, E.Cause(err, "write request")
-		}
-		n, err := conn.Read(buffer)
-		if err != nil {
-			return nil, E.Cause(err, "read response")
-		}
-		var response mDNS.Msg
-		err = response.Unpack(buffer[:n])
-		if err != nil {
-			return nil, E.Cause(err, "unpack response")
-		}
-		if response.Truncated && network == N.NetworkUDP {
-			continue
-		}
-		return &response, nil
-	}
-	panic("unexpected")
+	return t.exchange(ctx, message, domain)
 }

dns/transport/local/local_darwin.go

@@ -0,0 +1,143 @@
+//go:build darwin
+
+package local
+
+import (
+	"context"
+	"errors"
+	"net"
+
+	"github.com/sagernet/sing-box/adapter"
+	C "github.com/sagernet/sing-box/constant"
+	"github.com/sagernet/sing-box/dns"
+	"github.com/sagernet/sing-box/dns/transport/hosts"
+	"github.com/sagernet/sing-box/log"
+	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing/common"
+	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
+	M "github.com/sagernet/sing/common/metadata"
+	N "github.com/sagernet/sing/common/network"
+	"github.com/sagernet/sing/service"
+
+	mDNS "github.com/miekg/dns"
+)
+
+func RegisterTransport(registry *dns.TransportRegistry) {
+	dns.RegisterTransport[option.LocalDNSServerOptions](registry, C.DNSTypeLocal, NewTransport)
+}
+
+var _ adapter.DNSTransport = (*Transport)(nil)
+
+type Transport struct {
+	dns.TransportAdapter
+	ctx           context.Context
+	logger        logger.ContextLogger
+	hosts         *hosts.File
+	dialer        N.Dialer
+	preferGo      bool
+	fallback      bool
+	dhcpTransport dhcpTransport
+	resolver      net.Resolver
+}
+
+type dhcpTransport interface {
+	adapter.DNSTransport
+	Fetch() ([]M.Socksaddr, error)
+	Exchange0(ctx context.Context, message *mDNS.Msg, servers []M.Socksaddr) (*mDNS.Msg, error)
+}
+
+func NewTransport(ctx context.Context, logger log.ContextLogger, tag string, options option.LocalDNSServerOptions) (adapter.DNSTransport, error) {
+	transportDialer, err := dns.NewLocalDialer(ctx, options)
+	if err != nil {
+		return nil, err
+	}
+	transportAdapter := dns.NewTransportAdapterWithLocalOptions(C.DNSTypeLocal, tag, options)
+	return &Transport{
+		TransportAdapter: transportAdapter,
+		ctx:              ctx,
+		logger:           logger,
+		hosts:            hosts.NewFile(hosts.DefaultPath),
+		dialer:           transportDialer,
+		preferGo:         options.PreferGo,
+	}, nil
+}
+
+func (t *Transport) Start(stage adapter.StartStage) error {
+	if stage != adapter.StartStateStart {
+		return nil
+	}
+	inboundManager := service.FromContext[adapter.InboundManager](t.ctx)
+	for _, inbound := range inboundManager.Inbounds() {
+		if inbound.Type() == C.TypeTun {
+			t.fallback = true
+			break
+		}
+	}
+	if !C.IsIos {
+		if t.fallback {
+			t.dhcpTransport = newDHCPTransport(t.TransportAdapter, log.ContextWithOverrideLevel(t.ctx, log.LevelDebug), t.dialer, t.logger)
+			if t.dhcpTransport != nil {
+				err := t.dhcpTransport.Start(stage)
+				if err != nil {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
+func (t *Transport) Close() error {
+	return common.Close(
+		t.dhcpTransport,
+	)
+}
+
+func (t *Transport) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.Msg, error) {
+	question := message.Question[0]
+	domain := dns.FqdnToDomain(question.Name)
+	if question.Qtype == mDNS.TypeA || question.Qtype == mDNS.TypeAAAA {
+		addresses := t.hosts.Lookup(domain)
+		if len(addresses) > 0 {
+			return dns.FixedResponse(message.Id, question, addresses, C.DefaultDNSTTL), nil
+		}
+	}
+	if !t.fallback {
+		return t.exchange(ctx, message, domain)
+	}
+	if !C.IsIos {
+		if t.dhcpTransport != nil {
+			dhcpTransports, _ := t.dhcpTransport.Fetch()
+			if len(dhcpTransports) > 0 {
+				return t.dhcpTransport.Exchange0(ctx, message, dhcpTransports)
+			}
+		}
+	}
+	if t.preferGo {
+		// Assuming the user knows what they are doing, we still execute the query which will fail.
+		return t.exchange(ctx, message, domain)
+	}
+	if question.Qtype == mDNS.TypeA || question.Qtype == mDNS.TypeAAAA {
+		var network string
+		if question.Qtype == mDNS.TypeA {
+			network = "ip4"
+		} else {
+			network = "ip6"
+		}
+		addresses, err := t.resolver.LookupNetIP(ctx, network, domain)
+		if err != nil {
+			var dnsError *net.DNSError
+			if errors.As(err, &dnsError) && dnsError.IsNotFound {
+				return nil, dns.RcodeRefused
+			}
+			return nil, err
+		}
+		return dns.FixedResponse(message.Id, question, addresses, C.DefaultDNSTTL), nil
+	}
+	if C.IsIos {
+		return nil, E.New("only A and AAAA queries are supported on iOS and tvOS when using NetworkExtension.")
+	} else {
+		return nil, E.New("only A and AAAA queries are supported on macOS when using NetworkExtension and DHCP unavailable.")
+	}
+}

dns/transport/local/local_darwin_dhcp.go

@@ -0,0 +1,16 @@
+//go:build darwin && with_dhcp
+
+package local
+
+import (
+	"context"
+
+	"github.com/sagernet/sing-box/dns"
+	"github.com/sagernet/sing-box/dns/transport/dhcp"
+	"github.com/sagernet/sing-box/log"
+	N "github.com/sagernet/sing/common/network"
+)
+
+func newDHCPTransport(transportAdapter dns.TransportAdapter, ctx context.Context, dialer N.Dialer, logger log.ContextLogger) dhcpTransport {
+	return dhcp.NewRawTransport(transportAdapter, ctx, dialer, logger)
+}

dns/transport/local/local_darwin_nodhcp.go

@@ -0,0 +1,15 @@
+//go:build darwin && !with_dhcp
+
+package local
+
+import (
+	"context"
+
+	"github.com/sagernet/sing-box/dns"
+	"github.com/sagernet/sing-box/log"
+	N "github.com/sagernet/sing/common/network"
+)
+
+func newDHCPTransport(transportAdapter dns.TransportAdapter, ctx context.Context, dialer N.Dialer, logger log.ContextLogger) dhcpTransport {
+	return nil
+}

dns/transport/local/local_fallback.go

@@ -1,205 +0,0 @@
-package local
-
-import (
-	"context"
-	"errors"
-	"net"
-
-	"github.com/sagernet/sing-box/adapter"
-	C "github.com/sagernet/sing-box/constant"
-	"github.com/sagernet/sing-box/dns"
-	"github.com/sagernet/sing-box/experimental/libbox/platform"
-	"github.com/sagernet/sing-box/log"
-	"github.com/sagernet/sing-box/option"
-	E "github.com/sagernet/sing/common/exceptions"
-	"github.com/sagernet/sing/service"
-
-	mDNS "github.com/miekg/dns"
-)
-
-func RegisterTransport(registry *dns.TransportRegistry) {
-	dns.RegisterTransport[option.LocalDNSServerOptions](registry, C.DNSTypeLocal, NewFallbackTransport)
-}
-
-type FallbackTransport struct {
-	adapter.DNSTransport
-	ctx      context.Context
-	fallback bool
-	resolver net.Resolver
-}
-
-func NewFallbackTransport(ctx context.Context, logger log.ContextLogger, tag string, options option.LocalDNSServerOptions) (adapter.DNSTransport, error) {
-	transport, err := NewTransport(ctx, logger, tag, options)
-	if err != nil {
-		return nil, err
-	}
-	return &FallbackTransport{
-		DNSTransport: transport,
-		ctx:          ctx,
-	}, nil
-}
-
-func (f *FallbackTransport) Start(stage adapter.StartStage) error {
-	if stage != adapter.StartStateStart {
-		return nil
-	}
-	platformInterface := service.FromContext[platform.Interface](f.ctx)
-	if platformInterface == nil {
-		return nil
-	}
-	inboundManager := service.FromContext[adapter.InboundManager](f.ctx)
-	for _, inbound := range inboundManager.Inbounds() {
-		if inbound.Type() == C.TypeTun {
-			// platform tun hijacks DNS, so we can only use cgo resolver here
-			f.fallback = true
-			break
-		}
-	}
-	return nil
-}
-
-func (f *FallbackTransport) Close() error {
-	return nil
-}
-
-func (f *FallbackTransport) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.Msg, error) {
-	if !f.fallback {
-		return f.DNSTransport.Exchange(ctx, message)
-	}
-	question := message.Question[0]
-	domain := dns.FqdnToDomain(question.Name)
-	if question.Qtype == mDNS.TypeA || question.Qtype == mDNS.TypeAAAA {
-		var network string
-		if question.Qtype == mDNS.TypeA {
-			network = "ip4"
-		} else {
-			network = "ip6"
-		}
-		addresses, err := f.resolver.LookupNetIP(ctx, network, domain)
-		if err != nil {
-			var dnsError *net.DNSError
-			if errors.As(err, &dnsError) && dnsError.IsNotFound {
-				return nil, dns.RcodeRefused
-			}
-			return nil, err
-		}
-		return dns.FixedResponse(message.Id, question, addresses, C.DefaultDNSTTL), nil
-	} else if question.Qtype == mDNS.TypeNS {
-		records, err := f.resolver.LookupNS(ctx, domain)
-		if err != nil {
-			var dnsError *net.DNSError
-			if errors.As(err, &dnsError) && dnsError.IsNotFound {
-				return nil, dns.RcodeRefused
-			}
-			return nil, err
-		}
-		response := &mDNS.Msg{
-			MsgHdr: mDNS.MsgHdr{
-				Id:       message.Id,
-				Rcode:    mDNS.RcodeSuccess,
-				Response: true,
-			},
-			Question: []mDNS.Question{question},
-		}
-		for _, record := range records {
-			response.Answer = append(response.Answer, &mDNS.NS{
-				Hdr: mDNS.RR_Header{
-					Name:   question.Name,
-					Rrtype: mDNS.TypeNS,
-					Class:  mDNS.ClassINET,
-					Ttl:    C.DefaultDNSTTL,
-				},
-				Ns: record.Host,
-			})
-		}
-		return response, nil
-	} else if question.Qtype == mDNS.TypeCNAME {
-		cname, err := f.resolver.LookupCNAME(ctx, domain)
-		if err != nil {
-			var dnsError *net.DNSError
-			if errors.As(err, &dnsError) && dnsError.IsNotFound {
-				return nil, dns.RcodeRefused
-			}
-			return nil, err
-		}
-		return &mDNS.Msg{
-			MsgHdr: mDNS.MsgHdr{
-				Id:       message.Id,
-				Rcode:    mDNS.RcodeSuccess,
-				Response: true,
-			},
-			Question: []mDNS.Question{question},
-			Answer: []mDNS.RR{
-				&mDNS.CNAME{
-					Hdr: mDNS.RR_Header{
-						Name:   question.Name,
-						Rrtype: mDNS.TypeCNAME,
-						Class:  mDNS.ClassINET,
-						Ttl:    C.DefaultDNSTTL,
-					},
-					Target: cname,
-				},
-			},
-		}, nil
-	} else if question.Qtype == mDNS.TypeTXT {
-		records, err := f.resolver.LookupTXT(ctx, domain)
-		if err != nil {
-			var dnsError *net.DNSError
-			if errors.As(err, &dnsError) && dnsError.IsNotFound {
-				return nil, dns.RcodeRefused
-			}
-			return nil, err
-		}
-		return &mDNS.Msg{
-			MsgHdr: mDNS.MsgHdr{
-				Id:       message.Id,
-				Rcode:    mDNS.RcodeSuccess,
-				Response: true,
-			},
-			Question: []mDNS.Question{question},
-			Answer: []mDNS.RR{
-				&mDNS.TXT{
-					Hdr: mDNS.RR_Header{
-						Name:   question.Name,
-						Rrtype: mDNS.TypeCNAME,
-						Class:  mDNS.ClassINET,
-						Ttl:    C.DefaultDNSTTL,
-					},
-					Txt: records,
-				},
-			},
-		}, nil
-	} else if question.Qtype == mDNS.TypeMX {
-		records, err := f.resolver.LookupMX(ctx, domain)
-		if err != nil {
-			var dnsError *net.DNSError
-			if errors.As(err, &dnsError) && dnsError.IsNotFound {
-				return nil, dns.RcodeRefused
-			}
-			return nil, err
-		}
-		response := &mDNS.Msg{
-			MsgHdr: mDNS.MsgHdr{
-				Id:       message.Id,
-				Rcode:    mDNS.RcodeSuccess,
-				Response: true,
-			},
-			Question: []mDNS.Question{question},
-		}
-		for _, record := range records {
-			response.Answer = append(response.Answer, &mDNS.MX{
-				Hdr: mDNS.RR_Header{
-					Name:   question.Name,
-					Rrtype: mDNS.TypeA,
-					Class:  mDNS.ClassINET,
-					Ttl:    C.DefaultDNSTTL,
-				},
-				Preference: record.Pref,
-				Mx:         record.Host,
-			})
-		}
-		return response, nil
-	} else {
-		return nil, E.New("only A, AAAA, NS, CNAME, TXT, MX queries are supported on current platform when using TUN, please switch to a fixed DNS server.")
-	}
-}

dns/transport/local/local_resolved.go

@@ -0,0 +1,14 @@
+package local
+
+import (
+	"context"
+
+	mDNS "github.com/miekg/dns"
+)
+
+type ResolvedResolver interface {
+	Start() error
+	Close() error
+	Object() any
+	Exchange(object any, ctx context.Context, message *mDNS.Msg) (*mDNS.Msg, error)
+}

dns/transport/local/local_resolved_linux.go

@@ -0,0 +1,230 @@
+package local
+
+import (
+	"context"
+	"errors"
+	"os"
+	"sync"
+	"sync/atomic"
+
+	"github.com/sagernet/sing-box/adapter"
+	C "github.com/sagernet/sing-box/constant"
+	"github.com/sagernet/sing-box/service/resolved"
+	"github.com/sagernet/sing-tun"
+	"github.com/sagernet/sing/common"
+	"github.com/sagernet/sing/common/control"
+	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
+	"github.com/sagernet/sing/common/x/list"
+	"github.com/sagernet/sing/service"
+
+	"github.com/godbus/dbus/v5"
+	mDNS "github.com/miekg/dns"
+)
+
+type DBusResolvedResolver struct {
+	ctx               context.Context
+	logger            logger.ContextLogger
+	interfaceMonitor  tun.DefaultInterfaceMonitor
+	interfaceCallback *list.Element[tun.DefaultInterfaceUpdateCallback]
+	systemBus         *dbus.Conn
+	resoledObject     atomic.Pointer[ResolvedObject]
+	closeOnce         sync.Once
+}
+
+type ResolvedObject struct {
+	dbus.BusObject
+	InterfaceIndex int32
+}
+
+func NewResolvedResolver(ctx context.Context, logger logger.ContextLogger) (ResolvedResolver, error) {
+	interfaceMonitor := service.FromContext[adapter.NetworkManager](ctx).InterfaceMonitor()
+	if interfaceMonitor == nil {
+		return nil, os.ErrInvalid
+	}
+	systemBus, err := dbus.SystemBus()
+	if err != nil {
+		return nil, err
+	}
+	return &DBusResolvedResolver{
+		ctx:              ctx,
+		logger:           logger,
+		interfaceMonitor: interfaceMonitor,
+		systemBus:        systemBus,
+	}, nil
+}
+
+func (t *DBusResolvedResolver) Start() error {
+	t.updateStatus()
+	t.interfaceCallback = t.interfaceMonitor.RegisterCallback(t.updateDefaultInterface)
+	err := t.systemBus.BusObject().AddMatchSignal(
+		"org.freedesktop.DBus",
+		"NameOwnerChanged",
+		dbus.WithMatchSender("org.freedesktop.DBus"),
+		dbus.WithMatchArg(0, "org.freedesktop.resolve1.Manager"),
+	).Err
+	if err != nil {
+		return E.Cause(err, "configure resolved restart listener")
+	}
+	go t.loopUpdateStatus()
+	return nil
+}
+
+func (t *DBusResolvedResolver) Close() error {
+	t.closeOnce.Do(func() {
+		if t.interfaceCallback != nil {
+			t.interfaceMonitor.UnregisterCallback(t.interfaceCallback)
+		}
+		if t.systemBus != nil {
+			_ = t.systemBus.Close()
+		}
+	})
+	return nil
+}
+
+func (t *DBusResolvedResolver) Object() any {
+	return common.PtrOrNil(t.resoledObject.Load())
+}
+
+func (t *DBusResolvedResolver) Exchange(object any, ctx context.Context, message *mDNS.Msg) (*mDNS.Msg, error) {
+	question := message.Question[0]
+	resolvedObject := object.(*ResolvedObject)
+	call := resolvedObject.CallWithContext(
+		ctx,
+		"org.freedesktop.resolve1.Manager.ResolveRecord",
+		0,
+		resolvedObject.InterfaceIndex,
+		question.Name,
+		question.Qclass,
+		question.Qtype,
+		uint64(0),
+	)
+	if call.Err != nil {
+		var dbusError dbus.Error
+		if errors.As(call.Err, &dbusError) && dbusError.Name == "org.freedesktop.resolve1.NoNameServers" {
+			t.updateStatus()
+		}
+		return nil, E.Cause(call.Err, " resolve record via resolved")
+	}
+	var (
+		records  []resolved.ResourceRecord
+		outflags uint64
+	)
+	err := call.Store(&records, &outflags)
+	if err != nil {
+		return nil, err
+	}
+	response := &mDNS.Msg{
+		MsgHdr: mDNS.MsgHdr{
+			Id:                 message.Id,
+			Response:           true,
+			Authoritative:      true,
+			RecursionDesired:   true,
+			RecursionAvailable: true,
+			Rcode:              mDNS.RcodeSuccess,
+		},
+		Question: []mDNS.Question{question},
+	}
+	for _, record := range records {
+		var rr mDNS.RR
+		rr, _, err = mDNS.UnpackRR(record.Data, 0)
+		if err != nil {
+			return nil, E.Cause(err, "unpack resource record")
+		}
+		response.Answer = append(response.Answer, rr)
+	}
+	return response, nil
+}
+
+func (t *DBusResolvedResolver) loopUpdateStatus() {
+	signalChan := make(chan *dbus.Signal, 1)
+	t.systemBus.Signal(signalChan)
+	for signal := range signalChan {
+		var restarted bool
+		if signal.Name == "org.freedesktop.DBus.NameOwnerChanged" {
+			if len(signal.Body) != 3 || signal.Body[2].(string) == "" {
+				continue
+			} else {
+				restarted = true
+			}
+		}
+		if restarted {
+			t.updateStatus()
+		}
+	}
+}
+
+func (t *DBusResolvedResolver) updateStatus() {
+	dbusObject, err := t.checkResolved(context.Background())
+	oldValue := t.resoledObject.Swap(dbusObject)
+	if err != nil {
+		var dbusErr dbus.Error
+		if !errors.As(err, &dbusErr) || dbusErr.Name != "org.freedesktop.DBus.Error.NameHasNoOwnerCould" {
+			t.logger.Debug(E.Cause(err, "systemd-resolved service unavailable"))
+		}
+		if oldValue != nil {
+			t.logger.Debug("systemd-resolved service is gone")
+		}
+		return
+	} else if oldValue == nil {
+		t.logger.Debug("using systemd-resolved service as resolver")
+	}
+}
+
+func (t *DBusResolvedResolver) checkResolved(ctx context.Context) (*ResolvedObject, error) {
+	dbusObject := t.systemBus.Object("org.freedesktop.resolve1", "/org/freedesktop/resolve1")
+	err := dbusObject.Call("org.freedesktop.DBus.Peer.Ping", 0).Err
+	if err != nil {
+		return nil, err
+	}
+	defaultInterface := t.interfaceMonitor.DefaultInterface()
+	if defaultInterface == nil {
+		return nil, E.New("missing default interface")
+	}
+	call := dbusObject.(*dbus.Object).CallWithContext(
+		ctx,
+		"org.freedesktop.resolve1.Manager.GetLink",
+		0,
+		int32(defaultInterface.Index),
+	)
+	if call.Err != nil {
+		return nil, err
+	}
+	var linkPath dbus.ObjectPath
+	err = call.Store(&linkPath)
+	if err != nil {
+		return nil, err
+	}
+	linkObject := t.systemBus.Object("org.freedesktop.resolve1", linkPath)
+	if linkObject == nil {
+		return nil, E.New("missing link object for default interface")
+	}
+	dnsProp, err := linkObject.GetProperty("org.freedesktop.resolve1.Link.DNS")
+	if err != nil {
+		return nil, err
+	}
+	var linkDNS []resolved.LinkDNS
+	err = dnsProp.Store(&linkDNS)
+	if err != nil {
+		return nil, err
+	}
+	if len(linkDNS) == 0 {
+		for _, inbound := range service.FromContext[adapter.InboundManager](t.ctx).Inbounds() {
+			if inbound.Type() == C.TypeTun {
+				return nil, E.New("No appropriate name servers or networks for name found")
+			}
+		}
+		return &ResolvedObject{
+			BusObject: dbusObject,
+		}, nil
+	} else {
+		return &ResolvedObject{
+			BusObject:      dbusObject,
+			InterfaceIndex: int32(defaultInterface.Index),
+		}, nil
+	}
+}
+
+func (t *DBusResolvedResolver) updateDefaultInterface(defaultInterface *control.Interface, flags int) {
+	t.updateStatus()
+}

dns/transport/local/local_resolved_stub.go

@@ -0,0 +1,14 @@
+//go:build !linux
+
+package local
+
+import (
+	"context"
+	"os"
+
+	"github.com/sagernet/sing/common/logger"
+)
+
+func NewResolvedResolver(ctx context.Context, logger logger.ContextLogger) (ResolvedResolver, error) {
+	return nil, os.ErrInvalid
+}

dns/transport/local/local_shared.go

@@ -0,0 +1,191 @@
+package local
+
+import (
+	"context"
+	"errors"
+	"math/rand"
+	"syscall"
+	"time"
+
+	"github.com/sagernet/sing-box/dns"
+	"github.com/sagernet/sing-box/dns/transport"
+	"github.com/sagernet/sing/common/buf"
+	E "github.com/sagernet/sing/common/exceptions"
+	M "github.com/sagernet/sing/common/metadata"
+	N "github.com/sagernet/sing/common/network"
+
+	mDNS "github.com/miekg/dns"
+)
+
+func (t *Transport) exchange(ctx context.Context, message *mDNS.Msg, domain string) (*mDNS.Msg, error) {
+	systemConfig := getSystemDNSConfig(t.ctx)
+	if systemConfig.singleRequest || !(message.Question[0].Qtype == mDNS.TypeA || message.Question[0].Qtype == mDNS.TypeAAAA) {
+		return t.exchangeSingleRequest(ctx, systemConfig, message, domain)
+	} else {
+		return t.exchangeParallel(ctx, systemConfig, message, domain)
+	}
+}
+
+func (t *Transport) exchangeSingleRequest(ctx context.Context, systemConfig *dnsConfig, message *mDNS.Msg, domain string) (*mDNS.Msg, error) {
+	var lastErr error
+	for _, fqdn := range systemConfig.nameList(domain) {
+		response, err := t.tryOneName(ctx, systemConfig, fqdn, message)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+		return response, nil
+	}
+	return nil, lastErr
+}
+
+func (t *Transport) exchangeParallel(ctx context.Context, systemConfig *dnsConfig, message *mDNS.Msg, domain string) (*mDNS.Msg, error) {
+	returned := make(chan struct{})
+	defer close(returned)
+	type queryResult struct {
+		response *mDNS.Msg
+		err      error
+	}
+	results := make(chan queryResult)
+	startRacer := func(ctx context.Context, fqdn string) {
+		response, err := t.tryOneName(ctx, systemConfig, fqdn, message)
+		if err == nil {
+			if response.Rcode != mDNS.RcodeSuccess {
+				err = dns.RcodeError(response.Rcode)
+			} else if len(dns.MessageToAddresses(response)) == 0 {
+				err = E.New(fqdn, ": empty result")
+			}
+		}
+		select {
+		case results <- queryResult{response, err}:
+		case <-returned:
+		}
+	}
+	queryCtx, queryCancel := context.WithCancel(ctx)
+	defer queryCancel()
+	var nameCount int
+	for _, fqdn := range systemConfig.nameList(domain) {
+		nameCount++
+		go startRacer(queryCtx, fqdn)
+	}
+	var errors []error
+	for {
+		select {
+		case <-ctx.Done():
+			return nil, ctx.Err()
+		case result := <-results:
+			if result.err == nil {
+				return result.response, nil
+			}
+			errors = append(errors, result.err)
+			if len(errors) == nameCount {
+				return nil, E.Errors(errors...)
+			}
+		}
+	}
+}
+
+func (t *Transport) tryOneName(ctx context.Context, config *dnsConfig, fqdn string, message *mDNS.Msg) (*mDNS.Msg, error) {
+	serverOffset := config.serverOffset()
+	sLen := uint32(len(config.servers))
+	var lastErr error
+	for i := 0; i < config.attempts; i++ {
+		for j := uint32(0); j < sLen; j++ {
+			server := config.servers[(serverOffset+j)%sLen]
+			question := message.Question[0]
+			question.Name = fqdn
+			response, err := t.exchangeOne(ctx, M.ParseSocksaddr(server), question, config.timeout, config.useTCP, config.trustAD)
+			if err != nil {
+				lastErr = err
+				continue
+			}
+			return response, nil
+		}
+	}
+	return nil, E.Cause(lastErr, fqdn)
+}
+
+func (t *Transport) exchangeOne(ctx context.Context, server M.Socksaddr, question mDNS.Question, timeout time.Duration, useTCP, ad bool) (*mDNS.Msg, error) {
+	if server.Port == 0 {
+		server.Port = 53
+	}
+	request := &mDNS.Msg{
+		MsgHdr: mDNS.MsgHdr{
+			Id:                uint16(rand.Uint32()),
+			RecursionDesired:  true,
+			AuthenticatedData: ad,
+		},
+		Question: []mDNS.Question{question},
+		Compress: true,
+	}
+	request.SetEdns0(buf.UDPBufferSize, false)
+	if !useTCP {
+		return t.exchangeUDP(ctx, server, request, timeout)
+	} else {
+		return t.exchangeTCP(ctx, server, request, timeout)
+	}
+}
+
+func (t *Transport) exchangeUDP(ctx context.Context, server M.Socksaddr, request *mDNS.Msg, timeout time.Duration) (*mDNS.Msg, error) {
+	conn, err := t.dialer.DialContext(ctx, N.NetworkUDP, server)
+	if err != nil {
+		return nil, err
+	}
+	defer conn.Close()
+	if deadline, loaded := ctx.Deadline(); loaded && !deadline.IsZero() {
+		newDeadline := time.Now().Add(timeout)
+		if deadline.After(newDeadline) {
+			deadline = newDeadline
+		}
+		conn.SetDeadline(deadline)
+	}
+	buffer := buf.Get(buf.UDPBufferSize)
+	defer buf.Put(buffer)
+	rawMessage, err := request.PackBuffer(buffer)
+	if err != nil {
+		return nil, E.Cause(err, "pack request")
+	}
+	_, err = conn.Write(rawMessage)
+	if err != nil {
+		if errors.Is(err, syscall.EMSGSIZE) {
+			return t.exchangeTCP(ctx, server, request, timeout)
+		}
+		return nil, E.Cause(err, "write request")
+	}
+	n, err := conn.Read(buffer)
+	if err != nil {
+		if errors.Is(err, syscall.EMSGSIZE) {
+			return t.exchangeTCP(ctx, server, request, timeout)
+		}
+		return nil, E.Cause(err, "read response")
+	}
+	var response mDNS.Msg
+	err = response.Unpack(buffer[:n])
+	if err != nil {
+		return nil, E.Cause(err, "unpack response")
+	}
+	if response.Truncated {
+		return t.exchangeTCP(ctx, server, request, timeout)
+	}
+	return &response, nil
+}
+
+func (t *Transport) exchangeTCP(ctx context.Context, server M.Socksaddr, request *mDNS.Msg, timeout time.Duration) (*mDNS.Msg, error) {
+	conn, err := t.dialer.DialContext(ctx, N.NetworkTCP, server)
+	if err != nil {
+		return nil, err
+	}
+	defer conn.Close()
+	if deadline, loaded := ctx.Deadline(); loaded && !deadline.IsZero() {
+		newDeadline := time.Now().Add(timeout)
+		if deadline.After(newDeadline) {
+			deadline = newDeadline
+		}
+		conn.SetDeadline(deadline)
+	}
+	err = transport.WriteMessage(conn, 0, request)
+	if err != nil {
+		return nil, err
+	}
+	return transport.ReadMessage(conn)
+}

dns/transport/local/resolv.go

@@ -10,11 +10,6 @@ import (
 	"time"
 )
 
-const (
-	// net.maxDNSPacketSize
-	maxDNSPacketSize = 1232
-)
-
 type resolverConfig struct {
 	initOnce    sync.Once
 	ch          chan struct{}
@@ -104,7 +99,7 @@ func (c *dnsConfig) serverOffset() uint32 {
 	return 0
 }
 
-func (conf *dnsConfig) nameList(name string) []string {
+func (c *dnsConfig) nameList(name string) []string {
 	l := len(name)
 	rooted := l > 0 && name[l-1] == '.'
 	if l > 254 || l == 254 && !rooted {
@@ -118,15 +113,15 @@ func (conf *dnsConfig) nameList(name string) []string {
 		return []string{name}
 	}
 
-	hasNdots := strings.Count(name, ".") >= conf.ndots
+	hasNdots := strings.Count(name, ".") >= c.ndots
 	name += "."
 	// l++
 
-	names := make([]string, 0, 1+len(conf.search))
+	names := make([]string, 0, 1+len(c.search))
 	if hasNdots && !avoidDNS(name) {
 		names = append(names, name)
 	}
-	for _, suffix := range conf.search {
+	for _, suffix := range c.search {
 		fqdn := name + suffix
 		if !avoidDNS(fqdn) && len(fqdn) <= 254 {
 			names = append(names, fqdn)

dns/transport/local/resolv_darwin_cgo.go

@@ -1,55 +0,0 @@
-//go:build darwin && cgo
-
-package local
-
-/*
-#include <stdlib.h>
-#include <stdio.h>
-#include <resolv.h>
-#include <arpa/inet.h>
-*/
-import "C"
-
-import (
-	"context"
-	"time"
-
-	E "github.com/sagernet/sing/common/exceptions"
-
-	"github.com/miekg/dns"
-)
-
-func dnsReadConfig(_ context.Context, _ string) *dnsConfig {
-	var state C.res_state
-	if C.res_ninit(state) != 0 {
-		return &dnsConfig{
-			servers:  defaultNS,
-			search:   dnsDefaultSearch(),
-			ndots:    1,
-			timeout:  5 * time.Second,
-			attempts: 2,
-			err:      E.New("libresolv initialization failed"),
-		}
-	}
-	conf := &dnsConfig{
-		ndots:    1,
-		timeout:  5 * time.Second,
-		attempts: int(state.retry),
-	}
-	for i := 0; i < int(state.nscount); i++ {
-		ns := state.nsaddr_list[i]
-		addr := C.inet_ntoa(ns.sin_addr)
-		if addr == nil {
-			continue
-		}
-		conf.servers = append(conf.servers, C.GoString(addr))
-	}
-	for i := 0; ; i++ {
-		search := state.dnsrch[i]
-		if search == nil {
-			break
-		}
-		conf.search = append(conf.search, dns.Fqdn(C.GoString(search)))
-	}
-	return conf
-}

dns/transport/local/resolv_test.go

@@ -0,0 +1,13 @@
+package local
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestDNSReadConfig(t *testing.T) {
+	t.Parallel()
+	require.NoError(t, dnsReadConfig(context.Background(), "/etc/resolv.conf").err)
+}

dns/transport/local/resolv_unix.go

@@ -1,4 +1,4 @@
-//go:build !windows && !(darwin && cgo)
+//go:build !windows
 
 package local
 

dns/transport/quic/http3.go

@@ -51,11 +51,11 @@ func NewHTTP3(ctx context.Context, logger log.ContextLogger, tag string, options
 	}
 	tlsOptions := common.PtrValueOrDefault(options.TLS)
 	tlsOptions.Enabled = true
-	tlsConfig, err := tls.NewClient(ctx, options.Server, tlsOptions)
+	tlsConfig, err := tls.NewClient(ctx, logger, options.Server, tlsOptions)
 	if err != nil {
 		return nil, err
 	}
-	stdConfig, err := tlsConfig.Config()
+	stdConfig, err := tlsConfig.STDConfig()
 	if err != nil {
 		return nil, err
 	}
@@ -102,7 +102,7 @@ func NewHTTP3(ctx context.Context, logger log.ContextLogger, tag string, options
 		destination:      &destinationURL,
 		headers:          headers,
 		transport: &http3.Transport{
-			Dial: func(ctx context.Context, addr string, tlsCfg *tls.STDConfig, cfg *quic.Config) (quic.EarlyConnection, error) {
+			Dial: func(ctx context.Context, addr string, tlsCfg *tls.STDConfig, cfg *quic.Config) (*quic.Conn, error) {
 				conn, dialErr := transportDialer.DialContext(ctx, N.NetworkUDP, serverAddr)
 				if dialErr != nil {
 					return nil, dialErr