feat: Support ShadowTLS v2 as Shadowsocks plugin (#330)

.github/workflows/prerelease.yml

@@ -36,14 +36,16 @@ jobs:
         run: make -j$(($(nproc) + 1)) releases
 
       - name: Delete current release assets
-        uses: andreaswilli/delete-release-assets-action@v2.0.0
+        uses: mknejp/delete-release-assets@v1
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
-          tag: Prerelease-${{ github.ref_name }}
+          tag_name: Prerelease-${{ github.ref_name }}
-          deleteOnlyFromDrafts: false
+          assets: |
+              *.zip
+              *.gz
 
       - name: Tag Repo
-        uses: richardsimko/update-tag@v1
+        uses: richardsimko/update-tag@v1.0.6
         with:
           tag_name: Prerelease-${{ github.ref_name }}
         env:
@@ -53,7 +55,6 @@ jobs:
         uses: softprops/action-gh-release@v1
         if: ${{  success() }}
         with:
-          tag: ${{ github.ref_name }}
           tag_name: Prerelease-${{ github.ref_name }}
           files: bin/*
           prerelease: true

README.md

@@ -34,6 +34,26 @@ Documentations are now moved to [GitHub Wiki](https://github.com/Dreamacro/clash
 
 ## Advanced usage for this branch
 
+## Build
+
+You should install [golang](https://go.dev) first.
+
+Then get the source code of Clash.Meta:
+```shell
+git clone https://github.com/MetaCubeX/Clash.Meta.git
+cd Clash.Meta && go mod download
+```
+
+If you can't visit github,you should set proxy first:
+```shell
+go env -w GOPROXY=https://goproxy.io,direct
+```
+
+So now you can build it:
+```shell
+go build
+```
+
 ### DNS configuration
 
 Support `geosite` with `fallback-filter`.

adapter/outbound/shadowsocks.go

@@ -10,11 +10,13 @@ import (
 	"github.com/Dreamacro/clash/common/structure"
 	"github.com/Dreamacro/clash/component/dialer"
 	C "github.com/Dreamacro/clash/constant"
+	"github.com/Dreamacro/clash/transport/shadowtls"
 	obfs "github.com/Dreamacro/clash/transport/simple-obfs"
 	"github.com/Dreamacro/clash/transport/socks5"
+	"github.com/Dreamacro/clash/transport/trojan"
 	v2rayObfs "github.com/Dreamacro/clash/transport/v2ray-plugin"
 
-	"github.com/metacubex/sing-shadowsocks"
+	shadowsocks "github.com/metacubex/sing-shadowsocks"
 	"github.com/metacubex/sing-shadowsocks/shadowimpl"
 	"github.com/sagernet/sing/common/bufio"
 	M "github.com/sagernet/sing/common/metadata"
@@ -27,9 +29,11 @@ type ShadowSocks struct {
 
 	option *ShadowSocksOption
 	// obfs
-	obfsMode    string
+	obfsMode        string
-	obfsOption  *simpleObfsOption
+	obfsOption      *simpleObfsOption
-	v2rayOption *v2rayObfs.Option
+	v2rayOption     *v2rayObfs.Option
+	shadowTLSOption *shadowTLSOption
+	tlsConnector    *trojan.Trojan
 }
 
 type ShadowSocksOption struct {
@@ -61,6 +65,11 @@ type v2rayObfsOption struct {
 	Mux            bool              `obfs:"mux,omitempty"`
 }
 
+type shadowTLSOption struct {
+	Password string `obfs:"password"`
+	Host     string `obfs:"host"`
+}
+
 // StreamConn implements C.ProxyAdapter
 func (ss *ShadowSocks) StreamConn(c net.Conn, metadata *C.Metadata) (net.Conn, error) {
 	switch ss.obfsMode {
@@ -75,6 +84,11 @@ func (ss *ShadowSocks) StreamConn(c net.Conn, metadata *C.Metadata) (net.Conn, e
 		if err != nil {
 			return nil, fmt.Errorf("%s connect error: %w", ss.addr, err)
 		}
+	case shadowtls.Mode:
+		if ss.tlsConnector == nil {
+			ss.tlsConnector = trojan.New(&trojan.Option{ServerName: ss.shadowTLSOption.Host, SkipCertVerify: false})
+		}
+		c = shadowtls.NewShadowTls(c, ss.shadowTLSOption.Password, ss.tlsConnector)
 	}
 	if metadata.NetWork == C.UDP && ss.option.UDPOverTCP {
 		return ss.method.DialConn(c, M.ParseSocksaddr(uot.UOTMagicAddress+":443"))
@@ -157,6 +171,7 @@ func NewShadowSocks(option ShadowSocksOption) (*ShadowSocks, error) {
 
 	var v2rayOption *v2rayObfs.Option
 	var obfsOption *simpleObfsOption
+	var shadowTLSOpt *shadowTLSOption
 	obfsMode := ""
 
 	decoder := structure.NewDecoder(structure.Option{TagName: "obfs", WeaklyTypedInput: true})
@@ -192,6 +207,12 @@ func NewShadowSocks(option ShadowSocksOption) (*ShadowSocks, error) {
 			v2rayOption.TLS = true
 			v2rayOption.SkipCertVerify = opts.SkipCertVerify
 		}
+	} else if option.Plugin == shadowtls.Mode {
+		obfsMode = shadowtls.Mode
+		shadowTLSOpt = &shadowTLSOption{}
+		if err := decoder.Decode(option.PluginOpts, shadowTLSOpt); err != nil {
+			return nil, fmt.Errorf("ss %s initialize shadow-tls-plugin error: %w", addr, err)
+		}
 	}
 
 	return &ShadowSocks{
@@ -206,10 +227,11 @@ func NewShadowSocks(option ShadowSocksOption) (*ShadowSocks, error) {
 		},
 		method: method,
 
-		option:      &option,
+		option:          &option,
-		obfsMode:    obfsMode,
+		obfsMode:        obfsMode,
-		v2rayOption: v2rayOption,
+		v2rayOption:     v2rayOption,
-		obfsOption:  obfsOption,
+		obfsOption:      obfsOption,
+		shadowTLSOption: shadowTLSOpt,
 	}, nil
 }
 

flake.nix

@@ -28,7 +28,7 @@
             inherit version;
             src = ./.;
 
-            vendorSha256 = "sha256-XVz2vts4on42lfxnov4jnUrHzSFF05+i1TVY3C7bgdw=";
+            vendorSha256 = "sha256-8cbcE9gKJjU14DNTLPc6nneEPZg7Akt+FlSDlPRvG5k=";
 
             # Do not build testing suit
             excludedPackages = [ "./test" ];

transport/shadowtls/shadowtls.go

@@ -0,0 +1,142 @@
+package shadowtls
+
+import (
+	"crypto/hmac"
+	"crypto/sha1"
+	"encoding/binary"
+	"fmt"
+	"hash"
+	"io"
+	"net"
+
+	"github.com/Dreamacro/clash/common/pool"
+	"github.com/Dreamacro/clash/transport/trojan"
+)
+
+const (
+	chunkSize           = 1 << 13
+	Mode         string = "shadow-tls"
+	hashLen      int    = 8
+	tlsHeaderLen int    = 5
+)
+
+// TLSObfs is shadowsocks tls simple-obfs implementation
+type ShadowTls struct {
+	net.Conn
+	password     []byte
+	remain       int
+	firstRequest bool
+	tlsConnector *trojan.Trojan
+}
+
+type HashedConn struct {
+	net.Conn
+	hasher hash.Hash
+}
+
+func newHashedStream(conn net.Conn, password []byte) HashedConn {
+	return HashedConn{
+		Conn:   conn,
+		hasher: hmac.New(sha1.New, password),
+	}
+}
+
+func (h HashedConn) Read(b []byte) (n int, err error) {
+	n, err = h.Conn.Read(b)
+	h.hasher.Write(b[:n])
+	return
+}
+
+func (to *ShadowTls) read(b []byte) (int, error) {
+	buf := pool.Get(tlsHeaderLen)
+	_, err := io.ReadFull(to.Conn, buf)
+	if err != nil {
+		return 0, fmt.Errorf("shadowtls read failed %w", err)
+	}
+	if buf[0] != 0x17 || buf[1] != 0x3 || buf[2] != 0x3 {
+		return 0, fmt.Errorf("invalid shadowtls header %v", buf)
+	}
+	length := int(binary.BigEndian.Uint16(buf[3:]))
+	pool.Put(buf)
+
+	if length > len(b) {
+		n, err := to.Conn.Read(b)
+		if err != nil {
+			return n, err
+		}
+		to.remain = length - n
+		return n, nil
+	}
+
+	return io.ReadFull(to.Conn, b[:length])
+}
+
+func (to *ShadowTls) Read(b []byte) (int, error) {
+	if to.remain > 0 {
+		length := to.remain
+		if length > len(b) {
+			length = len(b)
+		}
+
+		n, err := io.ReadFull(to.Conn, b[:length])
+		if err != nil {
+			return n, fmt.Errorf("shadowtls Read failed with %w", err)
+		}
+		to.remain -= n
+		return n, nil
+	}
+
+	return to.read(b)
+}
+
+func (to *ShadowTls) Write(b []byte) (int, error) {
+	length := len(b)
+	for i := 0; i < length; i += chunkSize {
+		end := i + chunkSize
+		if end > length {
+			end = length
+		}
+
+		n, err := to.write(b[i:end])
+		if err != nil {
+			return n, fmt.Errorf("shadowtls Write failed with %w, i=%d, end=%d, n=%d", err, i, end, n)
+		}
+	}
+	return length, nil
+}
+
+func (s *ShadowTls) write(b []byte) (int, error) {
+	var hashVal []byte
+	if s.firstRequest {
+		hashedConn := newHashedStream(s.Conn, s.password)
+		if _, err := s.tlsConnector.StreamConn(hashedConn); err != nil {
+			return 0, fmt.Errorf("tls connect failed with %w", err)
+		}
+		hashVal = hashedConn.hasher.Sum(nil)[:hashLen]
+		s.firstRequest = false
+	}
+
+	buf := pool.GetBuffer()
+	defer pool.PutBuffer(buf)
+	buf.Write([]byte{0x17, 0x03, 0x03})
+	binary.Write(buf, binary.BigEndian, uint16(len(b)+len(hashVal)))
+	buf.Write(hashVal)
+	buf.Write(b)
+	_, err := s.Conn.Write(buf.Bytes())
+	if err != nil {
+		// return 0 because errors occur here make the
+		// whole situation irrecoverable
+		return 0, err
+	}
+	return len(b), nil
+}
+
+// NewShadowTls return a ShadowTls
+func NewShadowTls(conn net.Conn, password string, tlsConnector *trojan.Trojan) net.Conn {
+	return &ShadowTls{
+		Conn:         conn,
+		password:     []byte(password),
+		firstRequest: true,
+		tlsConnector: tlsConnector,
+	}
+}

transport/simple-obfs/tls.go

@@ -109,7 +109,12 @@ func (to *TLSObfs) write(b []byte) (int, error) {
 	binary.Write(buf, binary.BigEndian, uint16(len(b)))
 	buf.Write(b)
 	_, err := to.Conn.Write(buf.Bytes())
-	return len(b), err
+	if err != nil {
+		// return 0 because errors occur here make the
+		// whole situation irrecoverable
+		return 0, err
+	}
+	return len(b), nil
 }
 
 // NewTLSObfs return a SimpleObfs

transport/trojan/trojan.go

@@ -8,18 +8,17 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
-	tlsC "github.com/Dreamacro/clash/component/tls"
 	"io"
 	"net"
 	"net/http"
 	"sync"
 
 	"github.com/Dreamacro/clash/common/pool"
+	tlsC "github.com/Dreamacro/clash/component/tls"
 	C "github.com/Dreamacro/clash/constant"
 	"github.com/Dreamacro/clash/transport/socks5"
 	"github.com/Dreamacro/clash/transport/vless"
 	"github.com/Dreamacro/clash/transport/vmess"
-
 	xtls "github.com/xtls/go"
 )
 
@@ -117,9 +116,6 @@ func (t *Trojan) StreamConn(conn net.Conn) (net.Conn, error) {
 		}
 
 		tlsConn := tls.Client(conn, tlsConfig)
-		if err := tlsConn.Handshake(); err != nil {
-			return nil, err
-		}
 		// fix tls handshake not timeout
 		ctx, cancel := context.WithTimeout(context.Background(), C.DefaultTLSTimeout)
 		defer cancel()