commit 74f37d9a32edee08cbbf3824dfc64eb9cfc6d7cc
Author: David Fifield <david(a)bamsoftware.com>
Date: Sun Nov 25 22:51:56 2012 -0800
Move WebSocket code to its own file.
---
websocket-transport/Makefile | 2 +-
websocket-transport/websocket-server.go | 132 +-----------------------
websocket-transport/websocket.go | 172 +++++++++++++++++++++++++++++++
3 files changed, 178 insertions(+), 128 deletions(-)
diff --git a/websocket-transport/Makefile b/websocket-transport/Makefile
index 1fb2f76..013debd 100644
--- a/websocket-transport/Makefile
+++ b/websocket-transport/Makefile
@@ -3,7 +3,7 @@ PROGRAMS = websocket-client websocket-server
all: $(PROGRAMS)
websocket-client: websocket-client.go socks.go pt.go
-websocket-server: websocket-server.go pt.go
+websocket-server: websocket-server.go pt.go websocket.go
%: %.go
go build -o $@ $^
diff --git a/websocket-transport/websocket-server.go b/websocket-transport/websocket-server.go
index c6effe4..a2f3652 100644
--- a/websocket-transport/websocket-server.go
+++ b/websocket-transport/websocket-server.go
@@ -1,15 +1,11 @@
package main
import (
- "bufio"
- "crypto/sha1"
- "encoding/base64"
"fmt"
"net"
"net/http"
"os"
"os/signal"
- "strings"
)
const defaultPort = 9901
@@ -22,128 +18,8 @@ func logDebug(format string, v ...interface{}) {
fmt.Fprintf(os.Stderr, format+"\n", v...)
}
-func httpError(w http.ResponseWriter, bufrw *bufio.ReadWriter, code int) {
- w.Header().Set("Connection", "close")
- bufrw.WriteString(fmt.Sprintf("HTTP/1.0 %d %s\r\n", code, http.StatusText(code)))
- w.Header().Write(bufrw)
- bufrw.WriteString("\r\n")
- bufrw.Flush()
-}
-
-func commaSplit(s string) []string {
- var result []string
- if strings.TrimSpace(s) == "" {
- return result
- }
- for _, e := range strings.Split(s, ",") {
- result = append(result, strings.TrimSpace(e))
- }
- return result
-}
-
-func containsCase(haystack []string, needle string) bool {
- for _, e := range haystack {
- if strings.ToLower(e) == strings.ToLower(needle) {
- return true
- }
- }
- return false
-}
-
-func sha1Hash(data string) []byte {
- h := sha1.New()
- h.Write([]byte(data))
- return h.Sum(nil)
-}
-
-func handler(w http.ResponseWriter, req *http.Request) {
- conn, bufrw, err := w.(http.Hijacker).Hijack()
- if err != nil {
- http.Error(w, err.Error(), http.StatusInternalServerError)
- return
- }
- defer conn.Close()
-
- // See RFC 6455 section 4.2.1 for this sequence of checks.
-
- // 1. An HTTP/1.1 or higher GET request, including a "Request-URI"...
- if req.Method != "GET" {
- httpError(w, bufrw, http.StatusMethodNotAllowed)
- return
- }
- if req.URL.Path != "/" {
- httpError(w, bufrw, http.StatusNotFound)
- return
- }
- // 2. A |Host| header field containing the server's authority.
- // We deliberately skip this test.
- // 3. An |Upgrade| header field containing the value "websocket",
- // treated as an ASCII case-insensitive value.
- if !containsCase(commaSplit(req.Header.Get("Upgrade")), "websocket") {
- httpError(w, bufrw, http.StatusBadRequest)
- return
- }
- // 4. A |Connection| header field that includes the token "Upgrade",
- // treated as an ASCII case-insensitive value.
- if !containsCase(commaSplit(req.Header.Get("Connection")), "Upgrade") {
- httpError(w, bufrw, http.StatusBadRequest)
- return
- }
- // 5. A |Sec-WebSocket-Key| header field with a base64-encoded value
- // that, when decoded, is 16 bytes in length.
- websocketKey := req.Header.Get("Sec-WebSocket-Key")
- key, err := base64.StdEncoding.DecodeString(websocketKey)
- if err != nil || len(key) != 16 {
- httpError(w, bufrw, http.StatusBadRequest)
- return
- }
- // 6. A |Sec-WebSocket-Version| header field, with a value of 13.
- // We also allow 8 from draft-ietf-hybi-thewebsocketprotocol-10.
- var knownVersions = []string{"8", "13"}
- websocketVersion := req.Header.Get("Sec-WebSocket-Version")
- if !containsCase(knownVersions, websocketVersion) {
- // "If this version does not match a version understood by the
- // server, the server MUST abort the WebSocket handshake
- // described in this section and instead send an appropriate
- // HTTP error code (such as 426 Upgrade Required) and a
- // |Sec-WebSocket-Version| header field indicating the
- // version(s) the server is capable of understanding."
- w.Header().Set("Sec-WebSocket-Version", strings.Join(knownVersions, ", "))
- httpError(w, bufrw, 426)
- return
- }
- // 7. Optionally, an |Origin| header field.
- // 8. Optionally, a |Sec-WebSocket-Protocol| header field, with a list of
- // values indicating which protocols the client would like to speak, ordered
- // by preference.
- _ = commaSplit(req.Header.Get("Sec-WebSocket-Protocol"))
- // 9. Optionally, a |Sec-WebSocket-Extensions| header field...
- // 10. Optionally, other header fields...
-
- // See RFC 6455 section 4.2.2, item 5 for these steps.
-
- // 1. A Status-Line with a 101 response code as per RFC 2616.
- bufrw.WriteString(fmt.Sprintf("HTTP/1.0 %d %s\r\n", http.StatusSwitchingProtocols, http.StatusText(http.StatusSwitchingProtocols)))
- // 2. An |Upgrade| header field with value "websocket" as per RFC 2616.
- w.Header().Set("Upgrade", "websocket")
- // 3. A |Connection| header field with value "Upgrade".
- w.Header().Set("Connection", "Upgrade")
- // 4. A |Sec-WebSocket-Accept| header field. The value of this header
- // field is constructed by concatenating /key/, defined above in step 4
- // in Section 4.2.2, with the string
- // "258EAFA5-E914-47DA-95CA-C5AB0DC85B11", taking the SHA-1 hash of this
- // concatenated value to obtain a 20-byte value and base64-encoding (see
- // Section 4 of [RFC4648]) this 20-byte hash.
- const magicGUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
- acceptKey := base64.StdEncoding.EncodeToString(sha1Hash(websocketKey + magicGUID))
- w.Header().Set("Sec-WebSocket-Accept", acceptKey)
- // 5. Optionally, a |Sec-WebSocket-Protocol| header field, with a value
- // /subprotocol/ as defined in step 4 in Section 4.2.2.
- // w.Header().Set("Sec-WebSocket-Protocol", "base64")
- // 6. Optionally, a |Sec-WebSocket-Extensions| header field...
- w.Header().Write(bufrw)
- bufrw.WriteString("\r\n")
- bufrw.Flush()
+func websocketHandler(ws *websocket) {
+ fmt.Printf("blah\n")
}
func startListener(addr *net.TCPAddr) (*net.TCPListener, error) {
@@ -152,7 +28,9 @@ func startListener(addr *net.TCPAddr) (*net.TCPListener, error) {
return nil, err
}
go func() {
- http.HandleFunc("/", handler)
+ var config websocketConfig
+ config.Subprotocols = []string{"base64"}
+ http.Handle("/", config.Handler(websocketHandler))
err = http.Serve(ln, nil)
if err != nil {
panic("http.Serve: " + err.Error())
diff --git a/websocket-transport/websocket.go b/websocket-transport/websocket.go
new file mode 100644
index 0000000..9ac9754
--- /dev/null
+++ b/websocket-transport/websocket.go
@@ -0,0 +1,172 @@
+package main
+
+import (
+ "bufio"
+ "crypto/sha1"
+ "encoding/base64"
+ "fmt"
+ "net"
+ "net/http"
+ "strings"
+)
+
+type websocketConfig struct {
+ Subprotocols []string
+}
+
+type websocket struct {
+ Conn net.Conn
+ Bufrw *bufio.ReadWriter
+ // Whether we are a client or a server implications for masking.
+ IsClient bool
+ Subprotocol string
+}
+
+func commaSplit(s string) []string {
+ var result []string
+ if strings.TrimSpace(s) == "" {
+ return result
+ }
+ for _, e := range strings.Split(s, ",") {
+ result = append(result, strings.TrimSpace(e))
+ }
+ return result
+}
+
+func containsCase(haystack []string, needle string) bool {
+ for _, e := range haystack {
+ if strings.ToLower(e) == strings.ToLower(needle) {
+ return true
+ }
+ }
+ return false
+}
+
+func sha1Hash(data string) []byte {
+ h := sha1.New()
+ h.Write([]byte(data))
+ return h.Sum(nil)
+}
+
+func httpError(w http.ResponseWriter, bufrw *bufio.ReadWriter, code int) {
+ w.Header().Set("Connection", "close")
+ bufrw.WriteString(fmt.Sprintf("HTTP/1.0 %d %s\r\n", code, http.StatusText(code)))
+ w.Header().Write(bufrw)
+ bufrw.WriteString("\r\n")
+ bufrw.Flush()
+}
+
+type WebSocketHTTPHandler struct {
+ config *websocketConfig
+ websocketCallback func(*websocket)
+}
+
+func (handler *WebSocketHTTPHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+ conn, bufrw, err := w.(http.Hijacker).Hijack()
+ if err != nil {
+ http.Error(w, err.Error(), http.StatusInternalServerError)
+ return
+ }
+ defer conn.Close()
+
+ // See RFC 6455 section 4.2.1 for this sequence of checks.
+
+ // 1. An HTTP/1.1 or higher GET request, including a "Request-URI"...
+ if req.Method != "GET" {
+ httpError(w, bufrw, http.StatusMethodNotAllowed)
+ return
+ }
+ if req.URL.Path != "/" {
+ httpError(w, bufrw, http.StatusNotFound)
+ return
+ }
+ // 2. A |Host| header field containing the server's authority.
+ // We deliberately skip this test.
+ // 3. An |Upgrade| header field containing the value "websocket",
+ // treated as an ASCII case-insensitive value.
+ if !containsCase(commaSplit(req.Header.Get("Upgrade")), "websocket") {
+ httpError(w, bufrw, http.StatusBadRequest)
+ return
+ }
+ // 4. A |Connection| header field that includes the token "Upgrade",
+ // treated as an ASCII case-insensitive value.
+ if !containsCase(commaSplit(req.Header.Get("Connection")), "Upgrade") {
+ httpError(w, bufrw, http.StatusBadRequest)
+ return
+ }
+ // 5. A |Sec-WebSocket-Key| header field with a base64-encoded value
+ // that, when decoded, is 16 bytes in length.
+ websocketKey := req.Header.Get("Sec-WebSocket-Key")
+ key, err := base64.StdEncoding.DecodeString(websocketKey)
+ if err != nil || len(key) != 16 {
+ httpError(w, bufrw, http.StatusBadRequest)
+ return
+ }
+ // 6. A |Sec-WebSocket-Version| header field, with a value of 13.
+ // We also allow 8 from draft-ietf-hybi-thewebsocketprotocol-10.
+ var knownVersions = []string{"8", "13"}
+ websocketVersion := req.Header.Get("Sec-WebSocket-Version")
+ if !containsCase(knownVersions, websocketVersion) {
+ // "If this version does not match a version understood by the
+ // server, the server MUST abort the WebSocket handshake
+ // described in this section and instead send an appropriate
+ // HTTP error code (such as 426 Upgrade Required) and a
+ // |Sec-WebSocket-Version| header field indicating the
+ // version(s) the server is capable of understanding."
+ w.Header().Set("Sec-WebSocket-Version", strings.Join(knownVersions, ", "))
+ httpError(w, bufrw, 426)
+ return
+ }
+ // 7. Optionally, an |Origin| header field.
+ // 8. Optionally, a |Sec-WebSocket-Protocol| header field, with a list of
+ // values indicating which protocols the client would like to speak, ordered
+ // by preference.
+ clientProtocols := commaSplit(req.Header.Get("Sec-WebSocket-Protocol"))
+ // 9. Optionally, a |Sec-WebSocket-Extensions| header field...
+ // 10. Optionally, other header fields...
+
+ var ws websocket
+ ws.Conn = conn
+ ws.Bufrw = bufrw
+ ws.IsClient = false
+
+ // See RFC 6455 section 4.2.2, item 5 for these steps.
+
+ // 1. A Status-Line with a 101 response code as per RFC 2616.
+ bufrw.WriteString(fmt.Sprintf("HTTP/1.0 %d %s\r\n", http.StatusSwitchingProtocols, http.StatusText(http.StatusSwitchingProtocols)))
+ // 2. An |Upgrade| header field with value "websocket" as per RFC 2616.
+ w.Header().Set("Upgrade", "websocket")
+ // 3. A |Connection| header field with value "Upgrade".
+ w.Header().Set("Connection", "Upgrade")
+ // 4. A |Sec-WebSocket-Accept| header field. The value of this header
+ // field is constructed by concatenating /key/, defined above in step 4
+ // in Section 4.2.2, with the string
+ // "258EAFA5-E914-47DA-95CA-C5AB0DC85B11", taking the SHA-1 hash of this
+ // concatenated value to obtain a 20-byte value and base64-encoding (see
+ // Section 4 of [RFC4648]) this 20-byte hash.
+ const magicGUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
+ acceptKey := base64.StdEncoding.EncodeToString(sha1Hash(websocketKey + magicGUID))
+ w.Header().Set("Sec-WebSocket-Accept", acceptKey)
+ // 5. Optionally, a |Sec-WebSocket-Protocol| header field, with a value
+ // /subprotocol/ as defined in step 4 in Section 4.2.2.
+ for _, clientProto := range clientProtocols {
+ for _, serverProto := range handler.config.Subprotocols {
+ if clientProto == serverProto {
+ ws.Subprotocol = clientProto
+ w.Header().Set("Sec-WebSocket-Protocol", clientProto)
+ break
+ }
+ }
+ }
+ // 6. Optionally, a |Sec-WebSocket-Extensions| header field...
+ w.Header().Write(bufrw)
+ bufrw.WriteString("\r\n")
+ bufrw.Flush()
+
+ // Call the WebSocket-specific handler.
+ handler.websocketCallback(&ws)
+}
+
+func (config *websocketConfig) Handler(f func(*websocket)) http.Handler {
+ return &WebSocketHTTPHandler{config, f}
+}
