修订shadowTls代码;取消shadowTls的readv, 添加writev

经过思考，readv应该不会有什么性能提升，因为需要解析数据并重新分包；
通过实现writev，可以将从tcp流readv得到的数据写入，配合readv得到性能提升

main.go

@@ -418,47 +418,49 @@ func handleNewIncomeConnection(inServer proxy.Server, defaultClientForThis proxy
 
 			wsConn, err := singleSer.Handshake(wrappedConn)
 
-			if errors.Is(err, httpLayer.ErrShouldFallback) {
+			if err != nil {
+				if errors.Is(err, httpLayer.ErrShouldFallback) {
 
-				meta := wsConn.(httpLayer.FallbackMeta)
+					meta := wsConn.(httpLayer.FallbackMeta)
 
-				iics.fallbackRequestPath = meta.Path
-				iics.fallbackFirstBuffer = meta.H1RequestBuf
-				iics.wrappedConn = meta.Conn
-				if meta.XFF != nil {
-					iics.cachedRemoteAddr = meta.XFF.String()
+					iics.fallbackRequestPath = meta.Path
+					iics.fallbackFirstBuffer = meta.H1RequestBuf
+					iics.wrappedConn = meta.Conn
+					if meta.XFF != nil {
+						iics.cachedRemoteAddr = meta.XFF.String()
+
+					}
+
+					if ce := iics.CanLogDebug("Single AdvLayer Check failed, will fallback."); ce != nil {
+
+						ce.Write(
+							zap.String("handler", inServer.AddrStr()),
+							zap.String("advLayer", adv),
+							zap.String("Reason", meta.Reason),
+							zap.String("validPath", advSer.GetPath()),
+							zap.String("gotMethod", meta.Method),
+							zap.String("gotPath", meta.Path),
+							zap.String("from", iics.cachedRemoteAddr),
+						)
+					}
+
+					passToOutClient(iics, true, nil, nil, netLayer.Addr{})
+					return
+
+				} else {
+					if ce := iics.CanLogErr("InServer Single AdvLayer handshake failed"); ce != nil {
+
+						ce.Write(
+							zap.String("handler", inServer.AddrStr()),
+							zap.String("advLayer", adv),
+							zap.Error(err),
+						)
+					}
+
+					wrappedConn.Close()
+					return
 
 				}
-
-				if ce := iics.CanLogDebug("Single AdvLayer Check failed, will fallback."); ce != nil {
-
-					ce.Write(
-						zap.String("handler", inServer.AddrStr()),
-						zap.String("advLayer", adv),
-						zap.String("Reason", meta.Reason),
-						zap.String("validPath", advSer.GetPath()),
-						zap.String("gotMethod", meta.Method),
-						zap.String("gotPath", meta.Path),
-						zap.String("from", iics.cachedRemoteAddr),
-					)
-				}
-
-				passToOutClient(iics, true, nil, nil, netLayer.Addr{})
-				return
-
-			} else if err != nil {
-				if ce := iics.CanLogErr("InServer Single AdvLayer handshake failed"); ce != nil {
-
-					ce.Write(
-						zap.String("handler", inServer.AddrStr()),
-						zap.String("advLayer", adv),
-						zap.Error(err),
-					)
-				}
-
-				wrappedConn.Close()
-				return
-
 			} else {
 				wrappedConn = wsConn
 

tlsLayer/client.go

@@ -53,7 +53,8 @@ func NewClient(conf Conf) *Client {
 	return c
 }
 
-func (c *Client) Handshake(underlay net.Conn) (tlsConn Conn, err error) {
+// utls和tls时返回tlsLayer.Conn, shadowTls1时返回underlay, shadowTls2时返回 普通 net.Conn
+func (c *Client) Handshake(underlay net.Conn) (result net.Conn, err error) {
 
 	switch c.tlsType {
 	case UTls_t:
@@ -65,7 +66,7 @@ func (c *Client) Handshake(underlay net.Conn) (tlsConn Conn, err error) {
 		if err != nil {
 			return
 		}
-		tlsConn = &conn{
+		result = &conn{
 			Conn:    utlsConn,
 			ptr:     unsafe.Pointer(utlsConn.Conn),
 			tlsType: UTls_t,
@@ -77,7 +78,7 @@ func (c *Client) Handshake(underlay net.Conn) (tlsConn Conn, err error) {
 			return
 		}
 
-		tlsConn = &conn{
+		result = &conn{
 			Conn:    officialConn,
 			ptr:     unsafe.Pointer(officialConn),
 			tlsType: Tls_t,
@@ -89,10 +90,7 @@ func (c *Client) Handshake(underlay net.Conn) (tlsConn Conn, err error) {
 			return
 		}
 
-		tlsConn = &conn{
-			Conn:    underlay,
-			tlsType: ShadowTls_t,
-		}
+		result = underlay
 
 	case ShadowTls2_t:
 
@@ -110,17 +108,9 @@ func (c *Client) Handshake(underlay net.Conn) (tlsConn Conn, err error) {
 			return
 		}
 
-		// err = tls.Client(rw, c.tlsConfig).Handshake()
-		// if err != nil {
-		// 	return
-		// }
-
-		tlsConn = &conn{
-			Conn: &shadowClientConn{
-				FakeAppDataConn: &FakeAppDataConn{Conn: rw},
-				sum:             hashR.Sum(),
-			},
-			tlsType: ShadowTls2_t,
+		result = &shadowClientConn{
+			FakeAppDataConn: &FakeAppDataConn{Conn: rw},
+			sum:             hashR.Sum(),
 		}
 
 	}

tlsLayer/fake.go

@@ -1,28 +1,20 @@
 package tlsLayer
 
 import (
-	"bytes"
-	"crypto/tls"
 	"encoding/binary"
-	"errors"
 	"io"
 	"net"
-	"syscall"
 
-	"github.com/e1732a364fed/v2ray_simple/netLayer"
 	"github.com/e1732a364fed/v2ray_simple/utils"
 )
 
-// 读写都按tls application data 的格式走，其实就是加个包头
+// 读写都按tls application data 的格式走，其实就是加个包头. 实现 utils.MultiWriter
 type FakeAppDataConn struct {
 	net.Conn
 	readRemaining int
 
 	OptionalReader          io.Reader
 	OptionalReaderRemainLen int
-
-	//for readv
-	rr syscall.RawConn
 }
 
 func (c *FakeAppDataConn) Read(p []byte) (n int, err error) {
@@ -63,46 +55,6 @@ func (c *FakeAppDataConn) Read(p []byte) (n int, err error) {
 	return
 }
 
-func WriteAppData(conn io.Writer, buf *bytes.Buffer, d []byte) (n int, err error) {
-	var h [5]byte
-	h[0] = 23
-	binary.BigEndian.PutUint16(h[1:3], tls.VersionTLS12)
-	binary.BigEndian.PutUint16(h[3:], uint16(len(d)))
-
-	shouldPut := false
-
-	if buf == nil {
-		buf = utils.GetBuf()
-		shouldPut = true
-	}
-	buf.Write(h[:])
-	buf.Write(d)
-
-	n, err = conn.Write(buf.Bytes())
-
-	if shouldPut {
-		utils.PutBuf(buf)
-
-	}
-	return
-}
-
-// 一般conn直接为tcp连接，而它是有系统缓存的，因此我们一般不需要特地创建一个缓存
-// 写两遍之后在发出
-func WriteAppDataNoBuf(conn io.Writer, d []byte) (n int, err error) {
-	var h [5]byte
-	h[0] = 23
-	binary.BigEndian.PutUint16(h[1:3], tls.VersionTLS12)
-	binary.BigEndian.PutUint16(h[3:], uint16(len(d)))
-
-	_, err = conn.Write(h[:])
-	if err != nil {
-		return
-	}
-	return conn.Write(d)
-
-}
-
 func (c *FakeAppDataConn) Write(p []byte) (n int, err error) {
 
 	const maxlen = 1 << 14
@@ -131,127 +83,13 @@ func (c *FakeAppDataConn) Upstream() any {
 	return c.Conn
 }
 
-func (c *FakeAppDataConn) WillReadBuffersBenifit() int {
-	//一般而言底层连接就是tcp
-	if r, rr := netLayer.IsConnGoodForReadv(c.Conn); r != 0 {
-		c.rr = rr
-	}
-
-	return 1
-}
-
-// ReadBuffers一次性尽可能多读几个buf, 每个buf内部都是一个完整的appdata
-func (c *FakeAppDataConn) ReadBuffers() (buffers [][]byte, err error) {
-
-	//最理想的情况是，一次性读到一个大包，我们根据tls包头分割出多个appdata，然后放入buffers中
-
-	//但是有可能读不完整
-
-	var reader io.Reader
-
-	wholeReadLen := 0
-	//一次性读取
-	if c.rr != nil {
-		readv_mem := utils.Get_readvMem()
-		buffers, err = utils.ReadvFrom(c.rr, readv_mem)
-		if err != nil {
-			return nil, err
-		}
-
-		reader = utils.BuffersToMultiReader(buffers)
-		wholeReadLen = utils.BuffersLen(buffers)
-	} else {
-		bs := utils.GetPacket()
-		wholeReadLen, err = c.Conn.Read(bs)
-		if err != nil {
-			return nil, err
-		}
-		reader = bytes.NewBuffer(bs[:wholeReadLen])
-	}
-	if wholeReadLen < 5 {
-		return nil, errors.New("FakeAppDataConn ReadBuffers too short")
-	}
-	wholeLeftLen := wholeReadLen
-
-	if c.readRemaining > 0 {
-		bs := utils.GetPacket()
-		var n int
-		n, err = c.Conn.Read(bs[:c.readRemaining])
-		c.readRemaining -= n
-		buffers = append(buffers, bs[:n])
-		return
-	}
-	for {
-		if wholeLeftLen < 5 {
-			reader = io.MultiReader(reader, c.Conn)
-			var tlsHeader [5]byte
-			_, err = io.ReadFull(reader, tlsHeader[:])
-			if err != nil {
-				return
-			}
-			thisAppDataLen := int(binary.BigEndian.Uint16(tlsHeader[3:]))
-			if tlsHeader[0] != 23 {
-				return nil, utils.ErrInErr{ErrDesc: "unexpected TLS record type: ", Data: tlsHeader[0]}
-			}
-			thisBs := utils.GetPacket()
-
-			var n int
-			n, err = reader.Read(thisBs[:thisAppDataLen])
-			if err != nil {
-				return
-			}
-			buffers = append(buffers, thisBs[:n])
-
-			if diff := thisAppDataLen - n; diff > 0 {
-				c.readRemaining = diff
-
-			} else if diff < 0 {
-				return nil, utils.ErrInErr{ErrDesc: "FakeAppDataConn ReadBuffers read n>thisAppDataLen ", Data: []int{n, thisAppDataLen}}
-			}
-			return
-
-		}
-
-		var tlsHeader [5]byte
-		_, err = io.ReadFull(reader, tlsHeader[:])
-		if err != nil {
-			return
-		}
-		wholeLeftLen -= 5
-
-		thisAppDataLen := int(binary.BigEndian.Uint16(tlsHeader[3:]))
-		if tlsHeader[0] != 23 {
-			return nil, utils.ErrInErr{ErrDesc: "unexpected TLS record type: ", Data: tlsHeader[0]}
-		}
-		thisBs := utils.GetPacket()
-
-		var n int
-		n, err = reader.Read(thisBs[:thisAppDataLen])
-		if err != nil {
-			return
-		}
-		buffers = append(buffers, thisBs[:n])
-
-		if diff := thisAppDataLen - n; diff > 0 {
-			c.readRemaining = diff
-			return
-
-		} else if diff < 0 {
-			return nil, utils.ErrInErr{ErrDesc: "FakeAppDataConn ReadBuffers read n>thisAppDataLen ", Data: []int{n, thisAppDataLen}}
-		}
-
-		wholeLeftLen -= thisAppDataLen
-
-		if wholeLeftLen == 0 {
-			return
-		}
-
-	}
-
-}
-func (c *FakeAppDataConn) PutBuffers(bss [][]byte) {
-	for _, v := range bss {
-		utils.PutPacket(v)
-	}
+func (c *FakeAppDataConn) WriteBuffers(bss [][]byte) (int64, error) {
+	// 在server端，从direct用readv读到的数据可以用 WriteBuffers写回，可以加速
 
+	allLen := utils.BuffersLen(bss)
+	err := WriteAppDataHeader(c.Conn, allLen)
+	if err != nil {
+		return 0, err
+	}
+	return utils.BuffersWriteTo(bss, c.Conn)
 }

tlsLayer/io.go

@@ -2,6 +2,7 @@ package tlsLayer
 
 import (
 	"bytes"
+	"crypto/tls"
 	"encoding/binary"
 	"errors"
 	"io"
@@ -84,3 +85,46 @@ func CopyTls12Handshake(isSrcClient bool, dst, src net.Conn) error {
 	}
 	return nil
 }
+
+func WriteAppData(conn io.Writer, buf *bytes.Buffer, d []byte) (n int, err error) {
+
+	shouldPut := false
+
+	if buf == nil {
+		buf = utils.GetBuf()
+		shouldPut = true
+	}
+	WriteAppDataHeader(buf, len(d))
+
+	buf.Write(d)
+
+	n, err = conn.Write(buf.Bytes())
+
+	if shouldPut {
+		utils.PutBuf(buf)
+
+	}
+	return
+}
+
+// 一般conn直接为tcp连接，而它是有系统缓存的，因此我们一般不需要特地创建一个缓存
+// 写两遍之后在发出
+func WriteAppDataNoBuf(w io.Writer, d []byte) (n int, err error) {
+
+	err = WriteAppDataHeader(w, len(d))
+	if err != nil {
+		return
+	}
+	return w.Write(d)
+
+}
+
+func WriteAppDataHeader(w io.Writer, len int) (err error) {
+	var h [5]byte
+	h[0] = 23
+	binary.BigEndian.PutUint16(h[1:3], tls.VersionTLS12)
+	binary.BigEndian.PutUint16(h[3:], uint16(len))
+
+	_, err = w.Write(h[:])
+	return
+}

tlsLayer/shadow.go

@@ -251,7 +251,7 @@ func shadowCopyHandshakeClientToFake(fakeConn, clientConn net.Conn, hashW *utils
 
 }
 
-// 第一次写时写入一个hash，其余直接使用 FakeAppDataConn
+// 第一次写时写入一个hash，其余直接使用 FakeAppDataConn. 实现 utils.MultiWriter
 type shadowClientConn struct {
 	*FakeAppDataConn
 	sum []byte
@@ -278,3 +278,26 @@ func (c *shadowClientConn) Write(p []byte) (n int, err error) {
 	}
 	return c.FakeAppDataConn.Write(p)
 }
+
+func (c *shadowClientConn) WriteBuffers(bss [][]byte) (int64, error) {
+	if c.sum != nil {
+		sum := c.sum
+		c.sum = nil
+
+		result, dup := utils.MergeBuffersWithPrefix(sum, bss)
+
+		allDataLen := len(result) - len(sum)
+
+		_, err := c.FakeAppDataConn.Write(result)
+
+		if dup {
+			utils.PutPacket(result)
+		}
+		if err != nil {
+			return 0, err
+		}
+		return int64(allDataLen), nil
+
+	}
+	return c.FakeAppDataConn.WriteBuffers(bss)
+}

utils/buffers.go

@@ -71,7 +71,9 @@ type SystemReadver interface {
 
 	所以websocket很有必要实现 WriteBuffers 方法.
 
-	目前实现 的有 vless/trojan 的 UserTCPConn ,  ws.Conn 以及 grpc 的 multiConn
+	目前实现 的有 vless/trojan 的 UserTCPConn ,  ws.Conn
+
+	WriteV本身几乎没什么加速，但是因为ReadV有加速，所以通过WriteV写入ReadV读到的数组才能配合ReadV加速
 */
 type MultiWriter interface {
 	WriteBuffers([][]byte) (int64, error)
@@ -90,7 +92,7 @@ type MultiReader interface {
 type BuffersReader interface {
 	ReadBuffers() ([][]byte, error)
 
-	//将 ReadBuffers 放回缓存，以便重复利用内存
+	//将 ReadBuffers 放回缓存，以便重复利用内存. 因为这里不确定这个buffers是如何获取到的, 所以由实现者自行确定
 	PutBuffers([][]byte)
 }
 
@@ -205,3 +207,39 @@ func BuffersToMultiReader(bs [][]byte) io.Reader {
 	}
 	return io.MultiReader(bufs...)
 }
+
+// similar to MergeBuffers. prefix must has content
+func MergeBuffersWithPrefix(prefix []byte, bs [][]byte) (result []byte, duplicate bool) {
+
+	b0 := prefix
+	if len(bs) == 0 {
+		return prefix, false
+	}
+	allLen := BuffersLen(bs) + len(prefix)
+
+	if allLen <= cap(b0) {
+		b0 = b0[:allLen]
+		cursor := len(b0)
+		for i := 0; i < len(bs); i++ {
+			cursor += copy(b0[cursor:], bs[i])
+		}
+		return b0, false
+	}
+
+	if allLen <= MaxPacketLen {
+		result = GetPacket()
+
+	} else {
+		result = make([]byte, allLen) //实际目前的readv实现也很难出现这种情况
+		// 一定要尽量避免这种情况，如果 MaxBufLen小于readv buf总长度，会导致严重的内存泄漏问题,
+		// 见github issue #24
+	}
+
+	cursor := copy(result, prefix)
+
+	for i := 0; i < len(bs); i++ {
+		cursor += copy(result[cursor:], bs[i])
+	}
+
+	return result[:allLen], true
+}