Clean/Fixup Readme

Update to work with Chrome

.gitignore

@@ -0,0 +1,9 @@
+*.xpi
+
+*.swp
+
+# Locally built binaries
+/native_application/gorecv
+/example_client/gosend
+
+/web-ext-artifacts

README.md

@@ -1,2 +1,118 @@
-#Clipboard Inserter
+# Native Inserter
-A simple addon whose purpose is to automatically insert contents of clipboard into the page
+
+Fork of the Clipboard Inserter whose purpose it is to automatically insert the
+data received by a native application into a broswer page.
+
+It is useful for use with text extraction tools like Textractor for looking up
+words in the browser.
+
+This repository contains the browser plugin, native application, native
+messaging manifest and an example client. Textractor plugin is not included.
+
+Currently this addon is not available on any of the browsers addon stores, nor
+are releases past the fork signed by our benevolent overlords at
+Mozilla/Google.
+
+Only tested on GNU/Linux with Firefox 91 ESR.
+
+## Install
+
+You will need:
+
+- This code
+- A go compiler
+- A browser supporting native extensions (eg modern Firefox, Chrome)
+
+1) Compile and install the native application
+2) Edit `native_inserter.json` to find the native application
+3) Put `native_inserter.json` into your browsers native messaging manifest directory
+4) Build and install the addon in your browser
+
+For this to be useful you will also need a sender, for example a [Textractor
+plugin](https://github.com/45Tatami/Textractor-TCPSender) and a HTML page ([for
+example](https://pastebin.com/raw/DRDE075L)) that the can be inserted into.
+
+### Firefox
+
+This addon is not signed. From the [official Firefox
+documentation](https://extensionworkshop.com/documentation/publish/signing-and-distribution-overview/):
+
+> Unsigned extensions can be installed in Developer Edition, Nightly, and ESR
+> versions of Firefox, after toggling the xpinstall.signatures.required
+> preference in about:config.
+
+You can download the unsigned build from the releases or follow the official
+instruction for building addons, for example via `web-ext`:
+
+```
+$ npm install -g web-ext
+$ web-ext build
+```
+
+You can then install the resulting zip via the `Install Add-On From File`
+dialog under `about:addons`.
+
+The native messaging manifest directory under linux is
+`~/.mozilla/native-messaging-hosts`.
+
+## How does it work
+
+The browser plugin starts a native application which creates a raw TCP listen
+socket currently on all interfaces on port 30501 for incoming connections.
+
+One or more applications (eg Textractor plugin) will connect to this socket and
+send messages. Messages consist of a 4 Byte little-endian length header and
+UTF-8 payload.
+
+The native application will forward the UTF-8 data to the browser plugin which
+in turn will insert the text into a webpage similar to the original clipboard
+version.
+
+## Troubleshooting
+
+The native application is writing to stderr. Browsers usually forward this to
+their default log.
+
+The browser addon itself will log to the console. Problems with the native
+messaging manifest might not necessarily be logged.
+
+If the native application does not run in the background after loading the
+add-on, double-check if the native messaging manifest is in the correct
+directory and has the binary path set correctly.
+
+## (Not so) FAQ
+
+#### Why not the clipboard
+
+Abusing the clipboard functionality to transfer data to the browser is ugly. It
+does also not work under Wayland which does not allow unfocused applications to
+access the clipboard.
+
+(No opinion here whether the native application/messaging setup is more or less
+ugly than the clipboard approach)
+
+It also has the bonus of working with VMs without setting up clipboard
+forwarding between host and guest.
+
+#### Why a native application
+
+The APIs including TCP listen sockets are no longer supported by modern
+Browsers. The only alternative would be connecting to a WebSocket server, but
+this has two drawbacks:
+
+1) The API only supports the client side protocol and does not implement a
+server. This would mean the sending side would need to be the server and the
+native application the client, which would not work with multiple senders.
+
+2) The sending side (eg C++ Textractor plugin) would need to implement a
+Websocket server which is a lot more work than raw tcp.
+
+## Bugs
+
+- Native messaging expects the length prefix in native byte order. Go does
+  neither have a non-unsafe way to convert an integer to a byte stream in
+  native order for writing nor a way to detect endianness. The native
+  application will write in little-endian, which will break the protocol on
+  big-endian machines
+- Messages over the native-messaging 1MB limit will be discarded instead of
+  split up

bg/index.html

@@ -0,0 +1,10 @@
+<html>
+  <head>
+    <meta charset="utf-8"/>
+    <script src="/default-options.js"></script>
+    <script src="monitor.js"></script>
+  </head>
+  <body>
+    <div id="paste-target" contenteditable="true" />
+  </body>
+</html>

bg/monitor.js

@@ -0,0 +1,59 @@
+console.log("I'm alive")
+
+let listeningTabs = []
+let options = defaultOptions
+
+chrome.storage.local.get(defaultOptions,
+    o => options = o)
+
+
+chrome.storage.onChanged.addListener((changes, area) => {
+    if(area === "local") {
+	const optionKeys = Object.keys(options)
+	for(key of Object.keys(changes)) {
+	    if(optionKeys.indexOf(key) >= 0) {
+		options[key] = changes[key].newValue
+	    }
+	}
+    }
+})
+
+chrome.browserAction.onClicked.addListener((tab) => {
+        toggleTab(tab.id)
+})
+
+napp = browser.runtime.connectNative("native_inserter")
+napp.onDisconnect.addListener((p) => {
+        if (p.error) {
+                console.error(`Disconnected native app due to an error: ${p.error.message}`)
+        }
+})
+napp.onMessage.addListener((msg) => {
+        console.log("Received: " + msg.body)
+        const pasteTarget = document.querySelector("#paste-target")
+        pasteTarget.innerText = msg.body
+        const content = pasteTarget.innerText
+        listeningTabs.forEach(id => notifyForeground(id, content))
+})
+
+function toggleTab(id) {
+        const index = listeningTabs.indexOf(id)
+        if(index >= 0) {
+                uninject(id)
+                listeningTabs.splice(index, 1)
+                chrome.browserAction.setBadgeText({ text: "", tabId: id })
+        } else {
+                chrome.tabs.executeScript({file: "/fg/insert.js"})
+                listeningTabs.push(id)
+                chrome.browserAction.setBadgeBackgroundColor({ color: "green", tabId: id })
+                chrome.browserAction.setBadgeText({ text: "ON", tabId: id })
+        }
+}
+
+function notifyForeground(id, text) {
+        chrome.tabs.sendMessage(id, { action: "insert", text, options })
+}
+
+function uninject(id) {
+    chrome.tabs.sendMessage(id, { action: "uninject" })
+}

data/inserter.js

@@ -1,6 +0,0 @@
-self.port.on('insert', (data, prefs) => {
-  var elem = document.createElement(prefs['element-name'])
-  elem.textContent = data
-  var container = document.querySelector(prefs['container-selector'])
-  document.body.appendChild(elem)
-})

default-options.js

@@ -0,0 +1,5 @@
+const defaultOptions = {
+    elemName: 'p',
+    containerSelector: 'body',
+    monitorInterval: 300
+}

example_client/go.mod

@@ -0,0 +1,3 @@
+module gosend
+
+go 1.17

example_client/main.go

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+package main
+
+import (
+	"bufio"
+	"encoding/binary"
+	"log"
+	"math"
+	"net"
+	"os"
+)
+
+const remote_addr = "localhost:30501"
+
+func main() {
+	c, err := net.Dial("tcp", remote_addr)
+	if err != nil {
+		log.Panic("Error connecting:", err)
+	}
+	defer c.Close()
+
+	log.Printf("Connected to '%s'. Please input lines\n", remote_addr)
+
+	s := bufio.NewScanner(os.Stdin)
+	for s.Scan() {
+		msg := []byte(s.Text())
+
+		msg_len := len(msg)
+		if msg_len > math.MaxUint32 {
+			log.Println("Message too long")
+			continue
+		}
+
+		len_buf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(len_buf, uint32(msg_len))
+
+		if _, err := c.Write(len_buf); err != nil {
+			log.Panic("Error sending len:", err)
+		}
+		if _, err := c.Write(msg); err != nil {
+			log.Panic("Error sending payload:", err)
+		}
+	}
+	if err := s.Err(); err != nil {
+		log.Println("Error reading:", err)
+	}
+}

fg/insert.js

@@ -0,0 +1,16 @@
+(() => {
+    const processMessage = msg => {
+	switch(msg.action) {
+	case "insert":
+	    const elem = document.createElement(msg.options.elemName)
+	    elem.textContent = msg.text
+	    document.querySelector(msg.options.containerSelector).appendChild(elem)
+	    break
+	case "uninject":
+	    chrome.runtime.onMessage.removeListener(processMessage)
+	    break
+	}    
+    }
+
+    chrome.runtime.onMessage.addListener(processMessage)
+})()

index.js

@@ -1,63 +0,0 @@
-var self = require('sdk/self');
-var clipboard = require('sdk/clipboard')
-var buttons = require('sdk/ui/button/action');
-var tabs = require('sdk/tabs');
-var { ToggleButton } = require('sdk/ui/button/toggle')
-var timers = require('sdk/timers')
-var { prefs } = require('sdk/simple-prefs')
-
-var button = ToggleButton({
-  id: "clipboard-inserter-btn",
-  label: "Toggle Clipboard Cnserter",
-  icon: {
-    16: "./icon16.png",
-    32: "./icon32.png",
-    64: "./icon64.png"
-  },
-  onChange: function(state) {
-    this.state('window', null)
-    let { checked } = this.state('tab')
-    checked = !checked
-    this.state('tab', { checked })
-    if(checked) {
-      enableMonitor()
-    } else {
-      disableMonitor()
-    }
-  }
-})
-//<div>Icons made by <a href="http://www.flaticon.com/authors/google" title="Google">Google</a> from <a href="http://www.flaticon.com" title="Flaticon">www.flaticon.com</a> is licensed by <a href="http://creativecommons.org/licenses/by/3.0/" title="Creative Commons BY 3.0" target="_blank">CC 3.0 BY</a></div>
-
-function enableMonitor() {
-  console.log("Enabling clipboard monitor")
-  tabs.activeTab.clinClipboardMonitor = new ClipboardMonitor()
-}
-
-function disableMonitor() {
-  console.log("Disabling clipboard monitor")
-  var monitor = tabs.activeTab.clinClipboardMonitor
-  if(monitor) {
-    timers.clearInterval(monitor.intervalID)
-    delete tabs.activeTab.clinClipboardMonitor
-  } else {
-    console.error("Trying to disable clipboard monitor on tab without active ClipboardMonitor!")
-  }
-}
-
-function ClipboardMonitor() {
-
-  var lastContent = ''
-
-  this.worker = tabs.activeTab.attach({ contentScriptFile: self.data.url('inserter.js') })
-
-  this.intervalID = timers.setInterval(() => {
-    if(clipboard.currentFlavors.indexOf('text') != -1) {
-      var currentContent = clipboard.get('text/unicode')
-      if(lastContent !== currentContent) {
-        this.worker.port.emit('insert', currentContent, prefs)
-        lastContent = currentContent
-      }
-    }
-  }, 100)
-
-}

manifest.json

@@ -0,0 +1,41 @@
+{
+    "manifest_version": 2,
+    "name": "Native Inserter",
+    "version": "1.0.0",
+
+    "description": "An addon that inserts contents received from a native application into a page. Forked from clipboard-inserter. Uses icon made by Google from www.flaticon.com licensed by CC 3.0 BY",
+
+    "icons": {},
+
+    "browser_specific_settings": {
+	"gecko": {
+	    "id": "@native-inserter",
+            "strict_min_version": "50.0"
+	}
+    },
+    
+    "permissions": [
+	"activeTab",
+	"storage",
+        "nativeMessaging",
+	"file://*/*"
+    ],
+
+    "browser_action": {
+	"browser_style": true,
+	"default_icon": {
+	    "16": "icon/icon16.png",
+	    "32": "icon/icon32.png",
+	    "64": "icon/icon64.png"
+	},
+	"default_title": "Toggle Native Inserter"
+    },
+    
+    "background": {
+	"page": "bg/index.html"
+    },
+
+    "options_ui": {
+	"page": "options.html"
+    }
+}

native_application/go.mod

@@ -0,0 +1,3 @@
+module gorecv
+
+go 1.17

native_application/main.go

@@ -0,0 +1,93 @@
+package main
+
+import (
+	"encoding/binary"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"net"
+)
+
+type Message struct {
+	Body string `json:"body"`
+}
+
+const MSG_SIZE_LIMIT = 1000 * 1000 // Unclear if 1MiB or 1MB, using lower bound
+const LISTEN_INTERFACE = ":30501"
+
+func main() {
+	log.Println("Listening on", LISTEN_INTERFACE)
+
+	l, err := net.Listen("tcp", LISTEN_INTERFACE)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer l.Close()
+
+	msg_pipe := make(chan string)
+
+	// Output routine
+	go func() {
+		for {
+			msg, err := json.Marshal(Message{<-msg_pipe})
+			if err != nil {
+				log.Println("Error encoding message:", err)
+				continue
+			}
+
+			msg_len := len(msg)
+			if msg_len >= MSG_SIZE_LIMIT {
+				log.Println("Message over webextension limit. Discarding")
+				continue
+			}
+
+			len_buf := make([]byte, 4)
+			binary.LittleEndian.PutUint32(len_buf, uint32(msg_len))
+
+			log.Println(len_buf, string(msg))
+			fmt.Print(string(len_buf))
+			fmt.Print(string(msg))
+		}
+	}()
+
+	// Accept connections
+	for {
+		conn, err := l.Accept()
+		if err != nil {
+			log.Println("Error accepting conn:", err)
+		}
+		go conn_hndlr(conn, msg_pipe)
+	}
+}
+
+func conn_hndlr(c net.Conn, ch chan<- string) {
+	defer c.Close()
+	log.Println("Connection opened:", c)
+	for {
+		msg, err := read_msg(c)
+		if err != nil {
+			break
+		}
+		ch <- msg
+	}
+	log.Println("Closing connection:", c)
+}
+
+func read_msg(c net.Conn) (string, error) {
+	len_buf := make([]byte, 4)
+
+	if _, err := io.ReadFull(c, len_buf); err != nil {
+		log.Println("Len read error:", err)
+		return "", err
+	}
+
+	msg_len := binary.LittleEndian.Uint32(len_buf)
+	msg_buf := make([]byte, msg_len)
+	if _, err := io.ReadFull(c, msg_buf); err != nil {
+		log.Println("Msg read error:", err)
+		return "", err
+	}
+
+	return string(msg_buf), nil
+}

native_inserter.json

@@ -0,0 +1,7 @@
+{
+  "name": "native_inserter",
+  "description": "Example host for native messaging",
+  "path": "/usr/local/bin/gorecv",
+  "type": "stdio",
+  "allowed_extensions": [ "@native-inserter" ]
+}

options.html

@@ -0,0 +1,29 @@
+<html>
+  <head>
+    <meta charset="utf-8"/>
+    <script src="default-options.js"></script>
+    <script src="options.js"></script>
+    <link href="forms-min.css" rel="stylesheet"/>
+  </head>
+  <body>
+    <form class="pure-form pure-form-aligned">
+      <fieldset>
+	<div class="pure-control-group">
+	  <label for="elem-name">Element name </label>
+	  <input id="elem-name" type="text"
+		 title="Element name used when inserting the clipboard contents"/>
+	</div>
+	<div class="pure-control-group">
+	  <label for="container-selector">Container selector </label>
+	  <input id="container-selector" type="text"
+		 title="Css selector used to find element into which new elements will be inserted. Default value - 'body' - means that new elements will be appended at the end of the document."/>
+	</div>
+	<div class="pure-control-group">
+	  <label for="monitor-interval">Timer interval </label>
+	  <input id="monitor-interval" type="number" min="100" step="10"
+		 title="Time (in milliseconds) between clipboard checks. Low values may cause performance problems."/>
+	</div>
+      </fieldset>
+    </form>
+  </body>
+</html>

options.js

@@ -0,0 +1,21 @@
+document.addEventListener("DOMContentLoaded", () => {
+    const elemName = document.querySelector("#elem-name"),
+	  containerSelector = document.querySelector("#container-selector"),
+	  monitorInterval = document.querySelector("#monitor-interval")
+
+    const storage = chrome.storage.local
+    
+    storage.get(defaultOptions, o => {
+	elemName.value = o.elemName
+	containerSelector.value = o.containerSelector
+	monitorInterval.value = o.monitorInterval
+    })
+    elemName.onchange = () => storage.set({ elemName: elemName.value })
+    containerSelector.onchange = () => storage.set({ containerSelector: containerSelector.value })
+    monitorInterval.onchange = () => {
+	const newVal = monitorInterval.value
+	if(newVal >= 100) {
+	    storage.set({ monitorInterval: monitorInterval.value })
+	}
+    }
+})

package.json

@@ -1,28 +0,0 @@
-{
-  "title": "Clipboard Inserter",
-  "name": "clipboard-inserter",
-  "version": "0.0.1",
-  "description": "A simple addon whose purpose is to automatically insert contents of clipboard into the page. Uses icon made by Google from www.flaticon.com licensed by CC 3.0 BY",
-  "main": "index.js",
-  "author": "Yoitsumi",
-  "engines": {
-    "firefox": ">=38.0a1",
-    "fennec": ">=38.0a1"
-  },
-  "license": "MIT",
-  "keywords": [
-    "jetpack"
-  ],
-  "preferences": [{
-    "name": "element-name",
-    "title": "Added element name",
-    "type": "string",
-    "value": "p"
-  }, {
-    "name": "container-selector",
-    "title": "Containing element selector",
-    "description": "css selector of the element which should contain added elements. If you don't know what this means leaving this as 'body' will just append at the end of the document",
-    "type": "string",
-    "value": "body"
-  }]
-}

test/test-index.js

@@ -1 +0,0 @@
-var main = require("../");