Web Same-Origin-Policy Lab Zutao Zhu 11/06/2009

Outline Background Setting SOP

Background Document Object Model (DOM) Cookie XMLHttpRequest HTML LiveHTTPHeaders extension for Firefox

DOM The Document Object Model (DOM) is a cross-platform and language-independent convention for representing and interacting with objects in HTML, XHTML and XML documents. – from wiki cross-platformlanguageobjectsHTMLXHTMLXML

Cookie Cookies are placeholders for server- provided data in the web browser typically used to track sessions. Each cookie is a key-value pair such as "color=green" and may have some optional attributes. Web applications can create a cookie in the web browser using the set-cookie header in the HTTP response.

Cookie (cont.) After cookies are created, web browsers attach the cookies in all the subsequent requests to the web application. In a JavaScript program, All the cookies in the web application can be referenced using document.cookie object. In cookie-based session-management schemes, web applications store the session identifier in a cookie in the web browser.

Use Live HTTP Header (tools)

XMLHttpRequest XMLHttpRequest has an important role in the AJAX web development technique. – from wiki AJAX xhr = new XMLHttpRequest(); xhr.open(POST," m/posting.php",true); xhr.send(null);

HTML p –frame –iframe –img –a

LiveHTTPHeaders Observe the post request Observe the response Observe the cookie

Setting about:config in address bar of Firefox

SOP Origin: –Protocol: file://, ftp://, etc. –Domain: microsoft.com, google.com, etc. –Port: 80, 8080, 21, 3128, etc. The SOP identifies each web site using its origin, and creates a context for each origin. For each origin, the web browser creates a context and stores the resources of the web application from the origin in the context. JavaScript programs from one origin are not allowed to access resources from another origin.

Examples checks against the URL " - - from wikiURL

Resources for SOP Cookie History URL Contents Etc.

URL When in URL bar, I input some cross domain web page, can you use “forward” and “backward”? Is the URL showing?

Tags do not honor SOP Find out by yourself!

Reference XMLHttpRequest / XMLHttpRequest /