Precondition
I own mysite.com
I do not own othersite.com, but I can embed javascript code there
Question
How to send analytic data from othersite.com to mysite.com ?
Expected : othersite.com client -> mysite.com server
Not expected : othersite.com client -> othersite.com server -> mysite.com server
Its principle seems like to be similar with Google Analytics, but I don't know the exact principle
I know that it couldn't be done by ajax due to cross-domain problem
How does it change if I own othersite.com ?
How to send analytic data without response ?
For example, Heap Analytics send analytic data without response
The default scenarion with Google Analytics (and all other Web Analytics Tools I know) is to transfer data across domains by dynamically creating an image with a source that points to the tracking server and appending user data (like unique id per user) as url parameters to the image source.
Apart from everything you send via the image source you will also get the data from the http request (ip adress, user agent etc).
For a simple system you could create a script that stores the url and http data directly to a database before it returns a (1 pixel transparent) image. If you want something scalable you would probably write the data to a log file and use some currently hyped big data technology (hadoop, hive etc) for processing.
Decoupling data collection and processing is a good idea in any case, in that allows you to more easily switch components of your tracking application for improved versions without affecting the other parts of the system.
Sending an image is reliable inasfar as it works for any browser without enabling any special configurations (cors etc). It is however rather easily blocked (users just have to block pixel images or redirect calls to your server via their host file).
If the other domain was yours you could
track via ajax
read the server logs directly or pipe them to a dashboard of your choice
If you do not have access physically to the server but the owners let you configure their name servers you could run all incoming http requests through your tracking script before redirecting them to the requested page.
I took a look at Heap Analytics. They send an image request just like the other tools:
https://heapanalytics.com/h?a=236035469&u=4184751431615606&v=2274541888&s=3701858993&b=web&z=2&h=%2F&d=heapanalytics.com&t=Heap%20%7C%20Mobile%20and%20Web%20Analytics&r=https%3A%2F%2Fwww.google.de%2F&k=Screen%20Dimensions&k=1050%20x%201680&k=Window%20Width&k=1973&k=Window%20Height&k=1039&tm=1432884624859
which returns http 200 response code and an 1 pixel transparent image, so it does not look like they "track without response" after all.
Related
I am using Jmeter in order to test a web application. The issue i am facing is that when i am running the recorded script. I cannot see the data getting added in the database or in the UI of the application.
I recorded a script in which i added the data but when i run it, the response code is 200 and i have added regular expression extractors wherever needed. But still with no luck.
While looking at the View Result Tree, I can even see the Response that data is getting added but not on UI or DB.
If your website is using cookies to handle user sessions, you must add to your Test plan HTTP Cookie Manager to save and send cookie in HTTP requests.
it stores and sends cookies just like a web browser. If you have an HTTP Request and the response contains a cookie, the Cookie Manager automatically stores that cookie and will use it for all future requests to that particular web site.
I get a photo(image file) from my user. I can access to their camera and they will take a photo and send that photo for me. Codes are written in JavaScript.
In my API, CORS is disabled and only requests from my site are valid.
I want to be sure that photo which i will get it, is a photo that is taken via camera(codes are written in JS).
I want to get a image from API endpoint. That value is get from user camera and will be send via ajax request.
Can user send custom value to API if CORS is disabled?
I know that client side user can access JS codes via browser inspector, but can user change JS codes and send custom value to CORS disabled API?
A user can send whatever they want to your HTTP endpoint.
HTTP endpoints are public. You have no control over what is sent to them.
A user could manually construct an HTTP request (e.g. with a tool like Postman or any programming language) and send whatever data they like without involving a browser at all.
Any client (it doesn't even need to be a browser) can send arbitrary values to your API. It does not need to be a photo taken from the camera, it does not even need to be a photo at all. And you cannot prevent that, or force a browser to do anything. That includes preventing savy users from messing with your JS code.
CORS is a client-side security measure implemented in many clients that prevents js code on other domains from accessing your API with the user's credentials. It does not help you here.
I'm attempting to create an app with Node.js (using http.createServer()) which will be a single page application with requests for data via XMLHttpRequest. To do this I need to be able to differentiate between a user navigating to my domain, and AJAX requests and requests generated by the browser for linked resources.
If the request is from the user I always want to return the index.html page which will handle requesting content but if the request is browser generated or AJAX and is for CSS, Javascript or other linked files I want to serve those files. Is there any way to detect this?
Looking at the request headers for the different file types I saw the referer header appeared when the request for content was generated by the page. I figured that was the solution I was looking for but that header is also set when a user clicks on a link to the page making it useless.
The only other thing which seems to change is the accept header which could sort of work but might not be a catch all solution. Any user requests always seem to have text/html as the preferred return type regardless of which url was entered. I could detect that but I'm pretty sure AJAX requests for html files would also have that accept header which would cause problems.
Is there anything I'm missing here (any headers or properties I can look for)?
Edit: I do not need the solution to protect files and I don't care about users bypassing it with their own requests. My intention is not to hide files or make them secure, but rather to keep any data that is requested within the scope of the app.
For example, if a user navigates to http://example.com/images/someimage.jpg they are instead shown the index.html file which can then show the image in a richer context and include all of the links and functionality to go with it.
TL/DR: I need to detect when someone is trying to access the app to then serve them the index page and have that send them the content they want. I also need to detect when the browser has requested resources (JS, CSS, HTML, images, etc) needed by the app to be able to actually return the resource not the index file.
In terms of HTTP protocol there are NO difference between a user-generated-query and a browser-generated-query.
Every query is just... a query.
You can make a query with a command line, with a browser, you can click a link, send some ascii text via telnet, request a proxy which will make the query for you, the server goal is never to identify how the query was requested by the user.
See for example a request made by a user on a reverse proxy cache, this query will never reach your server (response comes from the cache), the first query made to build this response could have been made by a real user or by a browser.
In terms of security trying to control that the user is never requesting data by-himself cannot be done by detecting that the query is a real human click (and search google for clickjacking if you want to be afraid). Every query that a browser can make can also be played by the user, every one, you have no way to prevent that.
Some browsers plugins are even doing pre-fetching, detecting links on the page and making the request before you do it yourself (if it's a GET query).
For ajax, some libraries like JQuery will add an X-Requested-With: XMLHttpRequest header, and this is used on most framework to detect ajax mode.
But it is more robust to depend on a location policy for that (like making your ajax queries with a /format/ajax, which could also be used on other ways (like /format/json, /format/html, or /format/csv).
Spending time on a location policy based routing is certainly more usefull.
But one thing can make a difference, POST queries are not indempotent, it means the browser cannot make a POST query without a real user interaction, because a POST query may alter the state of the session or the state of the server data (but js can make POST queries, this is just a default behavior of browsers). The browser will never automatically retrieve a POST query, so you could make a website where all users interactions are POST queries (via forms or via some js altering link clicks to send POST ajax queries instead). But I'm not that's your real goal.
Not technically an answer to the question but I found a simple solution which does what I want: prefix all app based requests with a subdomain eg. http://data.example.com/. It's then really simple to check the host header for that subdomain: if present send the resource else send the index page.
Using javascript one cannot convert an image (hosted on a different domain than the one the javascript comes from) into a canvas.
What's the security risk with that? It can't just be to avoid phishing, right?
Same origin policy stops any remote data from being accessible by a different domain. One of the main attacks this stops is being able to circumvent a user's login by waiting for them to be logged into another site, and then piggy-back your request on their authenticated session.
Whether the data loaded is an HTML snippet, an image file or anything else, it's blocked so you can't take advantage in any way (for example, by inspecting the pixel data of an image retrieved this way)
There is one tricky attack vector connected with external images: someone can post image which will be loaded from the external resource, which they control. After some time this url can be changed to return the request for the basic http authentication. So the other users will see windows requesting their login and password. Some users, especially non-experienced ones can enter the credentials of the attacking resources which will be sent to the attacker. So be careful with external resources.
Yes, I know you have to embed the google analytics javascript into your page.
But how is the collected information submitted to the google analytics server?
For example an AJAX request will not be possible because of the browsers security settings (cross domain scripting).
Maybe someone had already a look at the confusing google javascript code?
When html page makes a request for a ga.js file the http protocol sends big amount of data, about IP, refer, browers, language, system. There is no need to use ajax.
But still some data cant be achieved this way, so GA script puts image into html with additional parameters, take a look at this example:
http://www.google-analytics.com/__utm.gif?utmwv=4.3&utmn=1464271798&utmhn=www.example.com&utmcs=UTF-8&utmsr=1920x1200&utmsc=32-bit&utmul=en-us&utmje=1&utmfl=10.0%20r22&utmdt=Page title&utmhid=1805038256&utmr=0&utmp=/&utmac=cookie value
This is a blank image, sometimes called a tracking pixel, that GA puts into HTML.
Some good answers here which individually tend to hit on one method or another for sending the data. There's a valuable reference which I feel is missing from the above answers, though, and covers all the methods.
Google refers to the different methods of sending data 'transport mechanisms'
From the Analytics.js documentation Google mentions the three main transport mechanisms that it uses to send data.
This specifies the transport mechanism with which hits will be sent. The options are 'beacon', 'xhr', or 'image'. By default, analytics.js will try to figure out the best method based on the hit size and browser capabilities. If you specify 'beacon' and the user's browser does not support the navigator.sendBeacon method, it will fall back to 'image' or 'xhr' depending on hit size.
One of the common and standard ways to send some of the data to Google (which is shown in Thinker's answer) is by adding the data as GET parameters to a tracking pixel. This would fall under the category which Google calls an 'image' transport.
Secondly, Google can use the 'beacon' transport method if the client's browser supports it. This is often my preferred method because it will attempt to send the information immediately. Or in Google's words:
This is useful in cases where you wish to track an event just before a user navigates away from your site, without delaying the navigation.
The 'xhr' transport mechanism is the third way that Google Analytics can send data back home, and the particular transport mechanism that is used can depend on things such as the size of the hit. (I'm not sure what other factors go into GA deciding the optimal transport mechanism to use)
In case you are curious how to force GA into using a specific transport mechanism, here is a sample code snippet which forces this event hit to be sent as a 'beacon':
ga('send', 'event', 'click', 'download-me', {transport: 'beacon'});
Hope this helps.
Also, if you are curious about this topic because you'd like to capture and send this data to your own site too, I recommend creating a binding to Google Analytics' send, which allows you to grab the payload and AJAX it to your own server.
ga(function(tracker) {
// Grab a reference to the default sendHitTask function.
originalSendHitTask = tracker.get('sendHitTask');
// Modifies sendHitTask to send a copy of the request to a local server after
// sending the normal request to www.google-analytics.com/collect.
tracker.set('sendHitTask', function(model) {
var payload = model.get('hitPayload');
originalSendHitTask(model);
var xhr = new XMLHttpRequest();
xhr.open('POST', '/index.php?task=mycollect', true);
xhr.send(payload);
});
});
Without looking at the code, I assume their data is collected from the HTTP headers they receive in the asynchronous request.
Remember that most browsers send data such as OS, platform, browser, version, locale, etc... Also they do have the IP so they can guesstimate your location. And I assume they have some sort of clever algorithm to decide whether you are a unique visitor or not.
Time on the site is probably calculated by using an onUnload() event.
Google Analytics web page provides detailed information of how Google Analytics server collect data. http://code.google.com/apis/analytics/docs/concepts/gaConceptsOverview.html
All Google Analytics data is collected and packed into the Request URL's query string and sent to Google Analytics server. The http request is made by a gif image(http://www.google-analytics.com/__utm.gif) activated by Google Analytics JS.
It's easy enough to tell by using something like Firebug's Net tab.
Ajax isn't needed - since data isn't being fetched from Google. They just encode the information in a query string, and then load a transparent gif using it.
To expand on other very good answers, Google does provide an API to track async "virtual pageviews" which are reported by website authors themselves in their scripts to Google.
_gaq.push(['_trackPageview', 'my_unique_action']);
They provide it so it is possible to track actions that are not part of regular page views and http requests.
Async tracking guide:
http://code.google.com/apis/analytics/docs/tracking/asyncUsageGuide.html#Syntax
Use the httpfox or firebug Firefox extension to figure out what HTTP requests the browser sends and what responses it receives.
I don't know how Google Analytics works, but one possibility is to make the browser download an image: <img src="http://my-analytics.com" width="1" height="1"> (with a single, transparent pixel), and log all the HTTP request headers (e.g. Referer:) on the server side.
//edit: see coment at the bottom
*Ok, find an answer during a discussion with a friend of mine :-)
The informations to google analytics are submitted in three ways:
List item
The HTTP Request can be analyzed with all informations of the http headers.
A cookie is recognized by the google analytics server.
An ajax call is done within the embeded javascript to submit such informations like display resolution, flash player version, etc.
These informations are not transmitted via the http headers.
*This is possible, because the ajax call is done in the context of the embedded javascript, so its no cross domain scripting. This was an error in reasoning by me.**