compression extension negotiation

lxzan · lxzan · commit 49e33738579a · 2023-08-09T21:22:57.000+08:00
diff --git a/client.go b/client.go
@@ -123,7 +123,12 @@ func (c *connector) handshake() (*Conn, *http.Response, error) {
 	if err != nil {
 		return nil, c.resp, err
 	}
-	var compressEnabled = c.option.CompressEnabled && strings.Contains(c.resp.Header.Get(internal.SecWebSocketExtensions.Key), "permessage-deflate")
+
+	extensions := c.resp.Header.Get(internal.SecWebSocketExtensions.Key)
+	var compressEnabled = c.option.CompressEnabled && strings.Contains(extensions, internal.PermessageDeflate)
+	if compressEnabled && strings.Contains(extensions, "_max_window_bits") {
+		return nil, c.resp, ErrCompressionNegotiation
+	}
 	return serveWebSocket(false, c.option.getConfig(), c.option.NewSessionStorage(), c.conn, br, c.eventHandler, compressEnabled, subprotocol), c.resp, nil
 }
 
@@ -132,7 +137,7 @@ func (c *connector) getSubProtocol() (string, error) {
 	b := internal.Split(c.resp.Header.Get(internal.SecWebSocketProtocol.Key), ",")
 	subprotocol := internal.GetIntersectionElem(a, b)
 	if len(a) > 0 && subprotocol == "" {
-		return "", ErrHandshake
+		return "", ErrSubprotocolNegotiation
 	}
 	return subprotocol, nil
 }
diff --git a/internal/others.go b/internal/others.go
@@ -6,6 +6,8 @@ import (
 	"net"
 )
 
+const PermessageDeflate = "permessage-deflate"
+
 type Pair struct {
 	Key string
 	Val string
diff --git a/protocol.go b/protocol.go
@@ -47,6 +47,15 @@ var (
 	// Handshake error, request header does not pass checksum.
 	ErrHandshake = errors.New("handshake error")
 
+	// ErrCompressionNegotiation &#21387;&#32553;&#25299;&#23637;&#21327;&#21830;&#22833;&#36133;
+	// &#23458;&#25143;&#31471;&#19981;&#25903;&#25345;server_max_window_bits&#21442;&#25968;
+	// The client does not support the server_max_window_bits parameter
+	ErrCompressionNegotiation = errors.New("invalid compression negotiation")
+
+	// ErrSubprotocolNegotiation &#23376;&#21327;&#35758;&#21327;&#21830;&#22833;&#36133;
+	// Sub-protocol negotiation failed
+	ErrSubprotocolNegotiation = errors.New("sub-protocol negotiation failed")
+
 	// ErrTextEncoding &#25991;&#26412;&#28040;&#24687;&#32534;&#30721;&#38169;&#35823;(&#24517;&#39035;&#26159;utf8&#32534;&#30721;)
 	// Text message encoding error (must be utf8)
 	ErrTextEncoding = errors.New("invalid text encoding")
diff --git a/updrader.go b/updrader.go
@@ -29,7 +29,7 @@ func (c *Upgrader) connectHandshake(r *http.Request, responseHeader http.Header,
 	if len(c.option.SubProtocols) > 0 {
 		subprotocol = internal.GetIntersectionElem(internal.Split(r.Header.Get(internal.SecWebSocketProtocol.Key), ","), c.option.SubProtocols)
 		if subprotocol == "" {
-			return "", ErrHandshake
+			return "", ErrSubprotocolNegotiation
 		}
 		responseHeader.Set(internal.SecWebSocketProtocol.Key, subprotocol)
 	}

Original file line number	Diff line number	Diff line change
`@@ -123,7 +123,12 @@ func (c connector) handshake() (Conn, *http.Response, error) {`
`123`	`123`	`if err != nil {`
`124`	`124`	`return nil, c.resp, err`
`125`	`125`	`}`
`126`		`- var compressEnabled = c.option.CompressEnabled && strings.Contains(c.resp.Header.Get(internal.SecWebSocketExtensions.Key), "permessage-deflate")`
	`126`	`+`
	`127`	`+ extensions := c.resp.Header.Get(internal.SecWebSocketExtensions.Key)`
	`128`	`+ var compressEnabled = c.option.CompressEnabled && strings.Contains(extensions, internal.PermessageDeflate)`
	`129`	`+ if compressEnabled && strings.Contains(extensions, "_max_window_bits") {`
	`130`	`+ return nil, c.resp, ErrCompressionNegotiation`
	`131`	`+ }`
`127`	`132`	`return serveWebSocket(false, c.option.getConfig(), c.option.NewSessionStorage(), c.conn, br, c.eventHandler, compressEnabled, subprotocol), c.resp, nil`
`128`	`133`	`}`
`129`	`134`
`@@ -132,7 +137,7 @@ func (c *connector) getSubProtocol() (string, error) {`
`132`	`137`	`b := internal.Split(c.resp.Header.Get(internal.SecWebSocketProtocol.Key), ",")`
`133`	`138`	`subprotocol := internal.GetIntersectionElem(a, b)`
`134`	`139`	`if len(a) > 0 && subprotocol == "" {`
`135`		`- return "", ErrHandshake`
	`140`	`+ return "", ErrSubprotocolNegotiation`
`136`	`141`	`}`
`137`	`142`	`return subprotocol, nil`
`138`	`143`	`}`
Original file line number	Diff line number	Diff line change
`@@ -6,6 +6,8 @@ import (`
`6`	`6`	`"net"`
`7`	`7`	`)`
`8`	`8`
	`9`	`+const PermessageDeflate = "permessage-deflate"`
	`10`	`+`
`9`	`11`	`type Pair struct {`
`10`	`12`	`Key string`
`11`	`13`	`Val string`
Original file line number	Diff line number	Diff line change
`@@ -29,7 +29,7 @@ func (c Upgrader) connectHandshake(r http.Request, responseHeader http.Header,`
`29`	`29`	`if len(c.option.SubProtocols) > 0 {`
`30`	`30`	`subprotocol = internal.GetIntersectionElem(internal.Split(r.Header.Get(internal.SecWebSocketProtocol.Key), ","), c.option.SubProtocols)`
`31`	`31`	`if subprotocol == "" {`
`32`		`- return "", ErrHandshake`
	`32`	`+ return "", ErrSubprotocolNegotiation`
`33`	`33`	`}`
`34`	`34`	`responseHeader.Set(internal.SecWebSocketProtocol.Key, subprotocol)`
`35`	`35`	`}`