網站可以檢測到瀏覽器擴展名正在被使用嗎？

Question

一個網站可以檢測到瀏覽器擴展名正在被使用嗎？具體而言，在這種情況下，該擴展的作者希望阻止網站識別用戶何時使用該擴展。那麼，對於一個通用的例子，雅虎的程序員能不能呢？編寫代碼，以便www.yahoo.com可以告訴用戶何時使用Firebug？如果雅虎！可以做到這一點，Firebug的製造商可以做些什麼來防止這種情況發生？

Answer 1

貌似可以使用JavaScript檢測在Firefox他們中的一些，這裏是一個文章：

http://jeremiahgrossman.blogspot.com/2006/08/i-know-what-youve-got-firefox.html

還有一：

http://ha.ckers.org/blog/20060823/detecting-firefox-extentions/

這裏是它是如何檢測：

// popular extensions. 
var e = { 
"Adblock Plus" : "chrome://adblockplus/skin/adblockplus.png", 
"Auto Copy" : "chrome://autocopy/skin/autocopy.png", 
"ColorZilla" : "chrome://colorzilla/skin/logo.png", 
"Customize Google" : "chrome://customizegoogle/skin/32x32.png", 
"DownThemAll!" : "chrome://dta/content/immagini/icon.png", 
"Faster Fox" : "chrome://fasterfox/skin/icon.png", 
"Flash Block" : "chrome://flashblock/skin/flash-on-24.png", 
"FlashGot" : "chrome://flashgot/skin/icon32.png", 
"Forecastfox" : "chrome://forecastfox/skin/images/icon.png", 
"Google Toolbar" : "chrome://google-toolbar/skin/icon.png", 
"Greasemonkey" : "chrome://greasemonkey/content/status_on.gif", 
"IE Tab" : "chrome://ietab/skin/ietab-button-ie16.png", 
"IE View" : "chrome://ieview/skin/ieview-icon.png", 
"JS View" : "chrome://jsview/skin/jsview.gif", 
"Live HTTP Headers" : "chrome://livehttpheaders/skin/img/Logo.png", 
"MeasureIt" : "chrome://measureit/skin/measureit.png", 
"SEO For Firefox" : "chrome://seo4firefox/content/icon32.png", 
"SEOpen" : "chrome://seopen/skin/seopen.png", 
"Search Status" : "chrome://searchstatus/skin/cax10.png", 
"Server Switcher" : "chrome://switcher/skin/icon.png", 
"StumbleUpon" : "chrome://stumbleupon/content/skin/logo32.png", 
"Tab Mix Plus" : "chrome://tabmixplus/skin/tmp.png", 
"Torrent-Search Toolbar" : "chrome://torrent-search/skin/v.png", 
"User Agent Switcher" : "chrome://useragentswitcher/content/logo.png", 
"View Source With" : "chrome://viewsourcewith/skin/ff/tb16.png", 
"Web Developer" : "chrome://webdeveloper/content/images/logo.png", 
"Unhide Passwords" : "chrome://unhidepw/skin/unhidepw.png", 
"UrlParams" : "chrome://urlparams/skin/urlparams32.png", 
"NewsFox" : "chrome://newsfox/skin/images/home.png", 
"Add N Edit Cookies" : "chrome://addneditcookies/skin/images/anec32.png", 
"GTDGmail" : "chrome://gtdgmail/content/gtd_lineitem.png", 
"QuickJava" : "chrome://quickjava/content/js.png", 
"Adblock Filterset.G Updater" : "chrome://unplug/skin/unplug.png", 
"BBCode" : "chrome://bbcode/skin/bbcode.png", 
"BugMeNot" : "chrome://bugmenot/skin/bugmenot.png", 
"ConQuery" : "chrome://conquery/skin/conquery.png", 
"Download Manager Tweak" : "chrome://downloadmgr/skin/downloadIcon.png", 
"Extended Cookie Manager" : "chrome://xcm/content/allowed.png", 
"FireBug" : "chrome://firebug/content/firebug32.png", 
"FoxyTunes" : "chrome://foxytunes/skin/logo.png", 
"MR Tech Disable XPI Install Delay" : "chrome://disable_xpi_delay/content/icon.png", 
"SessionSaver .2" : "chrome://sessionsaver/content/ss.png", 
"spooFX" : "chrome://spoofx/skin/main/spoofx.png", 
"Statusbar Clock" : "chrome://timestatus/skin/icon.png", 
"Torbutton" : "chrome://torbutton/skin/bigbutton_gr.png", 
"UnPlug" : "chrome://unplug/skin/unplug.png", 
"View Source Chart" : "chrome://vrs/skin/vrssmall.png", 
"XPather" : "chrome://xpather/content/iconka.png", 

}; 

if (is_mozilla) { 
showExtensions(); 
} 

function showExtensions() { 
for (var i in e) { 
    var img = document.createElement("img"); 
    img.setAttribute("border", '0'); 
    img.setAttribute("width", '0'); 
    img.setAttribute("height", '0'); 
    img.setAttribute("onload", "document.getElementById('ext'). 
appendChild(document.createElement('li')).innerHTML='" + i + "'"); 
    img.setAttribute("src", e[i]); 
} 

} 

因此，看起來像阻止這種檢測，你不需要有唯一的資源，可以識別插件或命名您的資源與現有插件相同的名稱來掩蓋。

Answer 2

該信息不是http協議的一部分，如果服務器端從瀏覽器獲取請求，它幾乎不會影響http頭中的信息類型。唯一可行的方法是通過JavaScript，這樣，作爲一名程序員，您可以創建JavaScript，從瀏覽器中獲取這些信息。但僅限於瀏覽器具有此功能的可用功能。

Answer 3

是的。當用戶請求幫助時，我使用它來自動填充隱藏表單字段，所以我知道是否有插件導致問題：

var plugins = ""; 
for (var i = 0; i < navigator.plugins.length; i++) 
{ 
    plugins += navigator.plugins[i].name; 
    if (i != (navigator.plugins.length - 1)) 
    { 
     plugins += ", "; 
    } 
}