Server http and https on the same port using a customized server (#2247)

server-main.go

@@ -91,15 +91,17 @@ type serverCmdConfig struct {
 }
 
 // configureServer configure a new server instance
-func configureServer(srvCmdConfig serverCmdConfig) *http.Server {
+func configureServer(srvCmdConfig serverCmdConfig) *MuxServer {
 	// Minio server config
-	apiServer := &http.Server{
-		Addr: srvCmdConfig.serverAddr,
-		// Adding timeout of 10 minutes for unresponsive client connections.
-		ReadTimeout:    10 * time.Minute,
-		WriteTimeout:   10 * time.Minute,
-		Handler:        configureServerHandler(srvCmdConfig),
-		MaxHeaderBytes: 1 << 20,
+	apiServer := &MuxServer{
+		Server: http.Server{
+			Addr: srvCmdConfig.serverAddr,
+			// Adding timeout of 10 minutes for unresponsive client connections.
+			ReadTimeout:    10 * time.Minute,
+			WriteTimeout:   10 * time.Minute,
+			Handler:        configureServerHandler(srvCmdConfig),
+			MaxHeaderBytes: 1 << 20,
+		},
 	}
 
 	// Returns configured HTTP server.
@@ -260,7 +262,7 @@ func serverMain(c *cli.Context) {
 	})
 
 	// Fetch endpoints which we are going to serve from.
-	endPoints := finalizeEndpoints(tls, apiServer)
+	endPoints := finalizeEndpoints(tls, &apiServer.Server)
 
 	// Prints the formatted startup message.
 	printStartupMessage(endPoints)

server-mux.go

@@ -0,0 +1,214 @@
+/*
+ * Minio Cloud Storage, (C) 2016 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package main
+
+import (
+	"crypto/tls"
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+var defaultHTTP2Methods = []string{
+	"PRI",
+}
+
+var defaultHTTP1Methods = []string{
+	"OPTIONS",
+	"GET",
+	"HEAD",
+	"POST",
+	"PUT",
+	"DELETE",
+	"TRACE",
+	"CONNECT",
+}
+
+// ConnBuf - contains network buffer to record data
+type ConnBuf struct {
+	buffer []byte
+	unRead bool
+	offset int
+}
+
+// MuxConn - implements a Read() which streams twice the firs bytes from
+// the incoming connection, to help peeking protocol
+type MuxConn struct {
+	net.Conn
+	lastError error
+	dataBuf   ConnBuf
+}
+
+// NewMuxConn - creates a new MuxConn instance
+func NewMuxConn(c net.Conn) *MuxConn {
+	h1 := longestWord(defaultHTTP1Methods)
+	h2 := longestWord(defaultHTTP2Methods)
+	max := h1
+	if h2 > max {
+		max = h2
+	}
+	return &MuxConn{Conn: c, dataBuf: ConnBuf{buffer: make([]byte, max+1)}}
+}
+
+// PeekProtocol - reads the first bytes, then checks if it is similar
+// to one of the default http methods
+func (c *MuxConn) PeekProtocol() string {
+	var n int
+	n, c.lastError = c.Conn.Read(c.dataBuf.buffer)
+	if n == 0 || (c.lastError != nil && c.lastError != io.EOF) {
+		return ""
+	}
+	c.dataBuf.unRead = true
+	for _, m := range defaultHTTP1Methods {
+		if strings.HasPrefix(string(c.dataBuf.buffer), m) {
+			return "http"
+		}
+	}
+	for _, m := range defaultHTTP2Methods {
+		if strings.HasPrefix(string(c.dataBuf.buffer), m) {
+			return "http2"
+		}
+	}
+	return "tls"
+}
+
+// Read - streams the MuxConn buffer when reset flag is activated, otherwise
+// streams from the incoming network connection
+func (c *MuxConn) Read(b []byte) (int, error) {
+	if c.dataBuf.unRead {
+		n := copy(b, c.dataBuf.buffer[c.dataBuf.offset:])
+		c.dataBuf.offset += n
+		if c.dataBuf.offset == len(c.dataBuf.buffer) {
+			// We finished copying all c.buffer, reset all
+			c.dataBuf.unRead = false
+			c.dataBuf.offset = 0
+			c.dataBuf.buffer = c.dataBuf.buffer[:]
+			if n < len(b) {
+				// Continue copying from socket if b still has room for data
+				tmpBuffer := make([]byte, len(b)-n-1)
+				nr, err := c.Conn.Read(tmpBuffer)
+				for idx, val := range tmpBuffer {
+					b[n+idx] = val
+				}
+				return n + nr, err
+			}
+		}
+		// We here return the last error
+		return n, c.lastError
+	}
+	return c.Conn.Read(b)
+}
+
+// MuxListener - encapuslates the standard net.Listener to inspect
+// the communication protocol upon network connection
+type MuxListener struct {
+	net.Listener
+	config *tls.Config
+}
+
+// NewMuxListener - creates new MuxListener, returns error when cert/key files are not found
+// or invalid
+func NewMuxListener(listener net.Listener, certPath, keyPath string) (MuxListener, error) {
+	var err error
+	config := &tls.Config{}
+	if config.NextProtos == nil {
+		config.NextProtos = []string{"http/1.1", "h2"}
+	}
+	config.Certificates = make([]tls.Certificate, 1)
+	config.Certificates[0], err = tls.LoadX509KeyPair(certPath, keyPath)
+	if err != nil {
+		return MuxListener{}, err
+	}
+	return MuxListener{Listener: listener, config: config}, nil
+}
+
+// Accept - peek the protocol to decide if we should wrap the
+// network stream with the TLS server
+func (l MuxListener) Accept() (net.Conn, error) {
+	c, err := l.Listener.Accept()
+	if err != nil {
+		return c, err
+	}
+	cmux := NewMuxConn(c)
+	protocol := cmux.PeekProtocol()
+	if protocol == "tls" {
+		return tls.Server(cmux, l.config), nil
+	}
+	return cmux, nil
+}
+
+// MuxServer - the main mux server
+type MuxServer struct {
+	http.Server
+}
+
+// ListenAndServeTLS - similar to the http.Server version. However, it has the
+// ability to redirect http requests to the correct HTTPS url if the client
+// mistakenly initiates a http connection over the https port
+func (m *MuxServer) ListenAndServeTLS(certFile, keyFile string) error {
+	listener, err := net.Listen("tcp", m.Server.Addr)
+	if err != nil {
+		return err
+	}
+	mux, err := NewMuxListener(listener, mustGetCertFile(), mustGetKeyFile())
+	if err != nil {
+		return err
+	}
+	err = http.Serve(mux,
+		http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			// We reach here when MuxListener.MuxConn is not wrapped with tls.Server
+			if r.TLS == nil {
+				u := url.URL{
+					Scheme:   "https",
+					Opaque:   r.URL.Opaque,
+					User:     r.URL.User,
+					Host:     r.Host,
+					Path:     r.URL.Path,
+					RawQuery: r.URL.RawQuery,
+					Fragment: r.URL.Fragment,
+				}
+				http.Redirect(w, r, u.String(), http.StatusMovedPermanently)
+			} else {
+				// Execute registered handlers
+				m.Server.Handler.ServeHTTP(w, r)
+			}
+		}))
+	return err
+}
+
+// ListenAndServe - Same as the http.Server version
+func (m *MuxServer) ListenAndServe() error {
+	return m.Server.ListenAndServe()
+}
+
+func longestWord(strings []string) int {
+	maxLen := 0
+	for _, m := range defaultHTTP1Methods {
+		if maxLen < len(m) {
+			maxLen = len(m)
+		}
+	}
+	for _, m := range defaultHTTP2Methods {
+		if maxLen < len(m) {
+			maxLen = len(m)
+		}
+	}
+
+	return maxLen
+}