From 4ab7c44c5b47baafb426e551b97a93f36dc00bd8 Mon Sep 17 00:00:00 2001
From: Zack Scholl <zack.scholl@gmail.com>
Date: Tue, 12 Nov 2019 07:50:12 -0800
Subject: [PATCH] use base64

---
 src/croc/croc.go              | 100 +++++++++-------
 src/webrtc/websend/index.html | 212 +++++++++++++++++-----------------
 2 files changed, 169 insertions(+), 143 deletions(-)

diff --git a/src/croc/croc.go b/src/croc/croc.go
index 36e24ab..86bbe16 100644
--- a/src/croc/croc.go
+++ b/src/croc/croc.go
@@ -3,6 +3,7 @@ package croc
 import (
 	"crypto/elliptic"
 	"crypto/md5"
+	"encoding/base64"
 	"encoding/json"
 	"fmt"
 	"time"
@@ -85,6 +86,43 @@ func (c *Client) Unbundle(msg []byte, payload interface{}) (err error) {
 	return
 }
 
+// SendWebsocketMessage communicates using base64
+func (c *Client) SendWebsocketMessage(wsmsg WebsocketMessage, encrypt bool) (err error) {
+	var b []byte
+	if encrypt {
+		b, err = c.Bundle(wsmsg)
+	} else {
+		b, err = json.Marshal(wsmsg)
+		if err != nil {
+			log.Error(err)
+			return
+		}
+	}
+	bd := base64.StdEncoding.EncodeToString(b)
+	err = c.ws.WriteMessage(1, []byte(bd))
+	return
+}
+
+// ReceiveWebsocketMessage communicates using base64
+func (c *Client) ReceiveWebsocketMessage(decrypt bool) (wsmsg WebsocketMessage, err error) {
+	_, msg, err := c.ws.ReadMessage()
+	if err != nil {
+		log.Error(err)
+		return
+	}
+	b, err := base64.StdEncoding.DecodeString(string(msg))
+	if decrypt {
+		err = c.Unbundle(b, &wsmsg)
+		if err != nil {
+			log.Error(err)
+			return
+		}
+	} else {
+		err = json.Unmarshal(b, &wsmsg)
+	}
+	return
+}
+
 // New establishes a new connection for transferring files between two instances.
 func New(ops Options) (c *Client, err error) {
 	c = new(Client)
@@ -107,6 +145,8 @@ func New(ops Options) (c *Client, err error) {
 		return
 	}
 
+	// connect to relay and determine
+	// whether it is receiver or offerer
 	err = c.connectToRelay()
 	if err != nil {
 		return
@@ -114,9 +154,10 @@ func New(ops Options) (c *Client, err error) {
 
 	if c.IsOfferer {
 		// offerer sends the first pake
-		c.ws.WriteJSON(WebsocketMessage{
+		c.SendWebsocketMessage(WebsocketMessage{
+			Message: "pake",
 			Payload: c.Pake.Bytes(),
-		})
+		}, false)
 	} else {
 		// answerer receives the first pake
 		err = c.getPAKE(true)
@@ -172,30 +213,19 @@ func New(ops Options) (c *Client, err error) {
 		if err != nil {
 			log.Error(err)
 		}
-		var msg []byte
-		msg, err = c.Bundle(WebsocketMessage{Message: "offer", Payload: offerJSON})
-		if err != nil {
-			log.Error(err)
-			return
-		}
-		err = c.ws.WriteMessage(websocket.BinaryMessage, msg)
+		err = c.SendWebsocketMessage(
+			WebsocketMessage{Message: "offer", Payload: offerJSON},
+			true,
+		)
 		if err != nil {
 			log.Error(err)
 			return
 		}
 
 		// wait for the answer
-		_, msg, err = c.ws.ReadMessage()
-		if err != nil {
-			log.Error(err)
-			return
-		}
 		var wsmsg WebsocketMessage
-		err = c.Unbundle(msg, &wsmsg)
-		if err != nil {
-			log.Error(err)
-			return
-		}
+		wsmsg, err = c.ReceiveWebsocketMessage(true)
+
 		err = setRemoteDescription(c.rtc, wsmsg.Payload)
 		if err != nil {
 			log.Error(err)
@@ -203,18 +233,8 @@ func New(ops Options) (c *Client, err error) {
 		}
 	} else {
 		// wait for the offer
-		var msg []byte
-		_, msg, err = c.ws.ReadMessage()
-		if err != nil {
-			log.Error(err)
-			return
-		}
 		var wsmsg WebsocketMessage
-		err = c.Unbundle(msg, &wsmsg)
-		if err != nil {
-			log.Error(err)
-			return
-		}
+		wsmsg, err = c.ReceiveWebsocketMessage(true)
 
 		err = setRemoteDescription(c.rtc, wsmsg.Payload)
 		if err != nil {
@@ -240,16 +260,15 @@ func New(ops Options) (c *Client, err error) {
 		if err != nil {
 			log.Error(err)
 		}
-		msg, err = c.Bundle(WebsocketMessage{Message: "answer", Payload: answerJSON})
-		if err != nil {
-			log.Error(err)
-			return
-		}
-		err = c.ws.WriteMessage(websocket.BinaryMessage, msg)
+		err = c.SendWebsocketMessage(
+			WebsocketMessage{Message: "answer", Payload: answerJSON},
+			true,
+		)
 		if err != nil {
 			log.Error(err)
 			return
 		}
+
 	}
 
 	err = <-finished
@@ -258,8 +277,7 @@ func New(ops Options) (c *Client, err error) {
 
 func (c *Client) getPAKE(keepSending bool) (err error) {
 	// answerer receives the first pake
-	var p WebsocketMessage
-	err = c.ws.ReadJSON(&p)
+	p, err := c.ReceiveWebsocketMessage(false)
 	if err != nil {
 		log.Error(err)
 		return
@@ -271,9 +289,10 @@ func (c *Client) getPAKE(keepSending bool) (err error) {
 	}
 	if keepSending {
 		//  sends back PAKE bytes
-		err = c.ws.WriteJSON(WebsocketMessage{
+		err = c.SendWebsocketMessage(WebsocketMessage{
+			Message: "pake",
 			Payload: c.Pake.Bytes(),
-		})
+		}, false)
 	}
 	return
 }
@@ -298,6 +317,7 @@ func (c *Client) connectToRelay() (err error) {
 		return
 	}
 
+	log.Debugf("connected and sending first message")
 	c.ws.WriteJSON(WebsocketMessage{
 		Message: "offerer",
 	})
diff --git a/src/webrtc/websend/index.html b/src/webrtc/websend/index.html
index e6fd70a..ec68d11 100644
--- a/src/webrtc/websend/index.html
+++ b/src/webrtc/websend/index.html
@@ -30,119 +30,125 @@
     Base64: <textarea id="remoteSessionDescription"></textarea> <br />
     <button onclick="startSession()"> Send Message </button> <br />
     <script>
-    function readBlob(opt_startByte, opt_stopByte) {
+        function readBlob(opt_startByte, opt_stopByte) {
 
-        var files = document.getElementById('files').files;
-        if (!files.length) {
-            alert('Please select a file!');
-            return;
+            var files = document.getElementById('files').files;
+            if (!files.length) {
+                alert('Please select a file!');
+                return;
+            }
+
+            var file = files[0];
+            var start = parseInt(opt_startByte) || 0;
+            var stop = parseInt(opt_stopByte) || file.size - 1;
+
+            var reader = new FileReader();
+
+            // If we use onloadend, we need to check the readyState.
+            reader.onloadend = function (evt) {
+                if (evt.target.readyState == FileReader.DONE) { // DONE == 2
+                    document.getElementById('byte_content').textContent = evt.target.result;
+                    document.getElementById('byte_range').textContent = ['Read bytes: ', start + 1, ' - ', stop + 1,
+                        ' of ', file.size, ' byte file'
+                    ].join('');
+                    sendMessage(evt.target.result);
+                }
+            };
+
+            var blob = file.slice(start, stop + 1);
+            reader.readAsBinaryString(blob);
         }
 
-        var file = files[0];
-        var start = parseInt(opt_startByte) || 0;
-        var stop = parseInt(opt_stopByte) || file.size - 1;
-
-        var reader = new FileReader();
-
-        // If we use onloadend, we need to check the readyState.
-        reader.onloadend = function(evt) {
-            if (evt.target.readyState == FileReader.DONE) { // DONE == 2
-                document.getElementById('byte_content').textContent = evt.target.result;
-                document.getElementById('byte_range').textContent = ['Read bytes: ', start + 1, ' - ', stop + 1,
-                    ' of ', file.size, ' byte file'
-                ].join('');
-                sendMessage(evt.target.result);
+        document.querySelector('.readBytesButtons').addEventListener('click', function (evt) {
+            if (evt.target.tagName.toLowerCase() == 'button') {
+                var startByte = evt.target.getAttribute('data-startbyte');
+                var endByte = evt.target.getAttribute('data-endbyte');
+                readBlob(startByte, endByte);
             }
+        }, false);
+
+
+
+
+        let pc = new RTCPeerConnection({
+            iceServers: [{
+                urls: 'stun:stun.l.google.com:19302'
+            }]
+        })
+        let log = msg => {
+            console.log(msg);
+        }
+
+        pc.onsignalingstatechange = e => log(pc.signalingState)
+        pc.oniceconnectionstatechange = e => log(pc.iceConnectionState)
+        pc.onicecandidate = event => {
+            if (event.candidate === null) {
+                log(JSON.stringify(pc.localDescription))
+            }
+        }
+
+
+
+        pc.ondatachannel = e => {
+            let dc = e.channel
+            log('New DataChannel ' + dc.label)
+            dc.onclose = () => log('dc has closed')
+            dc.onopen = () => {
+                log('dc has opened');
+            }
+            dc.onmessage = e => {
+                log(`Message from DataChannel '${dc.label}' payload '${e.data}'`)
+            }
+            window.sendMessage = e => {
+                let message = e;
+                if (message === '') {
+                    return alert('Message must not be empty')
+                }
+
+                dc.send(message)
+            }
+        }
+
+        window.startSession = () => {
+            pc.setRemoteDescription(new RTCSessionDescription(JSON.parse(atob(document.getElementById('remoteSessionDescription').value)))).catch(log)
+            pc.createAnswer().then(d => pc.setLocalDescription(d)).catch(log)
+        }
+
+        // websockets 
+        var socket;
+
+        const socketMessageListener = (event) => {
+            log(event);
+            log(event.data);
+            var data = JSON.parse(event.data);
+            console.log(data);
         };
-
-        var blob = file.slice(start, stop + 1);
-        reader.readAsBinaryString(blob);
-    }
-
-    document.querySelector('.readBytesButtons').addEventListener('click', function(evt) {
-        if (evt.target.tagName.toLowerCase() == 'button') {
-            var startByte = evt.target.getAttribute('data-startbyte');
-            var endByte = evt.target.getAttribute('data-endbyte');
-            readBlob(startByte, endByte);
+        const socketOpenListener = (event) => {
+            log('connected to websockets');
+            socket.send(JSON.stringify({
+                "Message": "offerer",
+            }))
         }
-    }, false);
-
-
-
-
-    let pc = new RTCPeerConnection({
-        iceServers: [{
-            urls: 'stun:stun.l.google.com:19302'
-        }]
-    })
-    let log = msg => {
-        console.log(msg);
-    }
-
-    pc.onsignalingstatechange = e => log(pc.signalingState)
-    pc.oniceconnectionstatechange = e => log(pc.iceConnectionState)
-    pc.onicecandidate = event => {
-        if (event.candidate === null) {
-            log(JSON.stringify(pc.localDescription))
-        }
-    }
-
-
-
-    pc.ondatachannel = e => {
-        let dc = e.channel
-        log('New DataChannel ' + dc.label)
-        dc.onclose = () => log('dc has closed')
-        dc.onopen = () => {
-            log('dc has opened');
-        }
-        dc.onmessage = e => {
-            log(`Message from DataChannel '${dc.label}' payload '${e.data}'`)
-        }
-        window.sendMessage = e => {
-            let message = e;
-            if (message === '') {
-                return alert('Message must not be empty')
+        const socketCloseListener = (event) => {
+            if (socket) {
+                log('Disconnected.');
             }
-
-            dc.send(message)
-        }
-    }
-
-    window.startSession = () => {
-        pc.setRemoteDescription(new RTCSessionDescription(JSON.parse(atob(document.getElementById('remoteSessionDescription').value)))).catch(log)
-        pc.createAnswer().then(d => pc.setLocalDescription(d)).catch(log)
-    }
-
-    // websockets 
-    var socket;
-
-    const socketMessageListener = (event) => {
-        log(event);
-    };
-    const socketOpenListener = (event) => {
-        log('Connected');
-    }
-    const socketCloseListener = (event) => {
-        if (socket) {
-            log('Disconnected.');
-        }
-        // var ws_url = window.origin.replace("http", "ws") + '/ws/test1';
-        var ws_url = "ws://localhost:8005/ws/test1";
-        log(`connecting to '${ws_url}'`)
-        socket = new WebSocket(ws_url);
-        socket.addEventListener('open', socketOpenListener);
-        socket.addEventListener('message', socketMessageListener);
-        socket.addEventListener('close', socketCloseListener);
-    };
-    socketCloseListener();
+            // var ws_url = window.origin.replace("http", "ws") + '/ws/test1';
+            var ws_url = "ws://localhost:8005/ws/test1";
+            log(`connecting to '${ws_url}'`)
+            socket = new WebSocket(ws_url);
+            socket.addEventListener('open', socketOpenListener);
+            socket.addEventListener('message', socketMessageListener);
+            socket.addEventListener('close', socketCloseListener);
+        };
+        socketCloseListener();
     </script>
     <script src="wasm_exec.js"></script>
     <script>
-    const go = new Go();
-    WebAssembly.instantiateStreaming(fetch("main.wasm"), go.importObject).then((result) => {
-        go.run(result.instance);
-    });
+        const go = new Go();
+        WebAssembly.instantiateStreaming(fetch("main.wasm"), go.importObject).then((result) => {
+            go.run(result.instance);
+        });
     </script>
 </body>