What is a good strategy for sniffing/tracing function calls between a Flex application and a ColdFusion-based backend running on ColdFusion server? I understand they use AMF protocol.
I'm used to using Fiddler to sniff transactions between HTTP clients and servers, and it works great as long as you're using plain text or XML HTTP requests and responses (including those over SSL) but it isn't much help for binary protocols like AMF over HTTP.
In my case, I do have access to the source code for the client and server, but I'm looking for an easy way to passively sniff traffic in any Flex + ColdFusion situation, without having to tweak anything on the server.
Wireshark: sniffing the glue that holds the internet together
http://www.wireshark.org/
http://www.charlesproxy.com/
Although not free, will decode AMF binary data and allows to trace SSL connections too.
ServiceCapture is another option. It decodes the binary AMF for you, if I remember correctly.
http://kevinlangdon.com/serviceCapture/
Firebug with the Flashbug plugin will show all decoded AMF messages both to and from a Flash app. Works well over HTTPS too.
https://addons.mozilla.org/en-us/firefox/addon/amf-explorer/.
The simple and poor man's trick. Create one cfc to log calls to the different cfc's and pages as you need. Dump it all to a table. Filter and sort at will. I have done this in the past and it has worked great. It's like putting in little fish hooks anywhere you want to know. This would likely give you the most application relevant data. If you need an example let me know.
ditto for wireshark (the artist formerly known as Ethereal). you can sniff at every protocol layer, and stitch together traffic streams.
Related
I am searching for a good method to transfer data over internet, and I work in C++/windows environment. The data is binary, a compressed blob of an extracted image. Input and requirements are as follows:
6kB/packet # 10 packets/sec (60kBytes per second)
Reliable data transfer
I am new to network programming and so far I could figure out that one of the following methods will be suitable.
Sockets
MSMQ (MS Message Queuing)
The Client runs on a browser (Shows realtime images on browser). While server runs native C++ code. Please let me know if there are any other methods for achieving the same? Which one should I go for and why?
If the server determines the pace at which images are sent, which is what it looks like, a server push style solution would make sense. What most browsers (and even non-browsers) are settling for these days are WebSockets.
The main advantage WebSockets have over most proprietary protocols, apart from becoming a widely adopted standard, is that they run on top of HTTP and can thus permeate (most) proxies and firewalls etc.
On the server side, you could potentially integrate node.js, which allows you to easily implement WebSockets, and comes with a lot of other libraries. It's written in C++, and extensible via C++ and JavaScript, which node.js hosts a VM for. node.js's main feature is being asynchronous at every level, making that style of programming the default.
But of course there are other ways to implement WebSockets on the server side, maybe node.js is more than you need. I have implemented a C++ extension for node.js on Windows and use socket.io to do WebSockets and non-WebSocket transports for older browsers, and that has worked out fine for me.
But that was textual data. In your binary data case, socket.io wouldn't do it, so you could check out other libraries that do binary over WebSockets.
Is there any specific reason why you cannot run a server on your windows machine? 60kb/seconds, looks like some kind of an embedded device?
Based on our description, you ned to show image information, in realtime on a browser. You can possibly use HTTP. but its stateless, meaning once the information is transferred, you lose the connection. You client needs to poll the C++/Windows machine. If you are prety confident the information generated is periodic, you can use this approach. This requires a server, so only if a yes to my first question
A chat protocol. Something like a Jabber client running on your client, and a Jabber server on your C++/Windows machine. Chat protocols allow almost realtime
While it may seem to make sense, I wouldn't use MSMQ in this scenario. You may not run into a problem now, but MSMQ messages are limited in size and you may eventually hit a wall because of this.
I would use TCP for this application, TCP is built with reliability in mind and you can simply feed data through a socket. You may have to figure out a very simple protocol yourself but it should be the best choice.
Unless you are using an embedded device that understands MSMQ out of the box, your best bet to use MSMQ would be to use a proxy and you are then still forced to play with TCP and possibly HTTP.
I do home automation that includes security cameras on my personal time and I use the .net micro framework and even if it did have MSMQ capabilities I still wouldn't use it.
I recommend that you look into MJPEG (Motion JPEG) which sounds exactly like what you would like to do.
http://www.codeproject.com/Articles/371955/Motion-JPEG-Streaming-Server
I am looking for tools that can be used for debugging web applications.I have narrowed my search to the following tools:
HTTPwatch.
Fiddler.
ieHTTPheader
liveHTTPheader.
It would be great if some of you having experience with these tools could discuss their pros and cons (features that you like or you think are missing in some of the tools but present in others).I am majorly confused between HTTPWatch and Fiddler, I would prefer Fiddler (being free) if it could fullfill all or most of HTTPWatch's features (however I am ready to pay for HTTPWatch if it's worth it).
P.S. - I know HTTPWatch and Fiddler are far more powerful than the other two tools (let me know if you disagree).
I am sure most of you would want more details as to what I would exactly like to do with these tools however I would like if you could compare these tools taking a broader perspective in mind comparing them as tools in general.
** Disclaimer: Posted by Simtec Limited **
Here's a list of the main advantages of HttpWatch (our product) and Fiddler. Of course we're biased, but we've tried to be objective:
HttpWatch Advantages
Shows requests that were read from
the browser cache without going onto network
Shows page level events, e.g. Render Start, DOM Load, etc
Handles SSL traffic without certificate warnings or requiring changes to trusted root CAs
Reduces 'observer effect' by not requiring HTTP proxy at network level
Groups requests by page
Fiddler Advantages
Works with almost any HTTP client not just Firefox and IE
Can intercept traffic from clients on non-Windows platforms, e.g. mobile devices
Requests can be intercepted and modified on the fly, e.g. change cookie value
Supports plugins to add extra functionality
Wireshark works at the network layer and of course gives you more information that the other tools you have mentioned here, however, if you want to debug web applications by breaking on requests/responses, modifying them and replaying - Fiddler is the tool for you!
Fiddler cannot however show TCP level information however and in such cases you will need Network Monitor or Wireshark.
If you specify what exactly you want to do with the 'debugger', one can suggest what's more appropriate for the job.
Fidler is good and simple to use. Wireshark is also worth considering since it gives a lot of extra information
You could also use Wireshark which allows you to analyze many protocols including TCP/IP.
A lab exercise from a University lecture on using Wireshark to analyze HTTP can be found here: Wireshark Lab: HTTP
take a look at HTTP Debugger Pro
It works with all browsers and custom software and doesn't change proxy settings.
So when I am debugging my web applications and such, I've used the Charles web proxy and debugger and love it. It's so nice to see what's being sent and received via port 80 and 443. I can see all the resources loading, not just from the "browser" per say, but also flash applications. I can also see how the calls are being made, and it pretty easy to reconstruct them. It's a great debugging tool and I love it.
So I'm wondering two things:
First, I'm wondering is if there is something similar I can use to watch traffic that might be coming though on other ports. I guess some desktop applications will use the internet, but not necessarily via http / https requests. I remember looking at some security tools a few years ago - there are a lot of security tools out there, like kismet / etherCap, ethershark, etc - is there one that does what I'm describing in an easy and intuitive way?
Also, I'm wondering if I am using my iPhone / iPad / Android device, how can I set up a proxy through my computer so I can watch the http/https requests that the device makes?
Found the answer to that one here: http://www.ravelrumba.com/blog/ipad-http-debugging/
I'm mostly on a Mac so anything that is Mac friendly would be extra helpful.
Thanks!
I believe you are looking for Wireshark. It allows you to monitor the network interface on your machine and be able to tell you sent/receive packets as well as their protocols. It also has a protocol decoder that can be used to get Layer 7 information about a IP stream. You can also do a "Follow TCP stream" which allows you to view the entire conversation of that connection. It's based on libpcap (Packet capture) which the built in tcpdump also uses.
The only downside for you web developers is that if you're using SSL encrypted sessions, you can't decode it. The endpoints of the SSL session are "above" (using OSI model) the layer at which wireshark (and similar tools) operate.
Here's a good list http://sectools.org/sniffers.html. I used Wireshark back when it was Ethereal. At that time it ran under X11, It looks like that has changed.
I am having a Web application sitting on IIS, and talking with [remote]Service-Machine.
I am not sure whether to choose TCP or Http, as the main protocol.
more details:
i will have more than one service\endpoint
some of them will be one-way
the other will be two-ways
the web pages will work infront of the services
we are talking about hi-scale web-site
I know the difference pretty well, but I am looking for a good benchmark, that shows how much faster is the TCP?
HTTP is a layer built ontop of the TCP layer to some what standardize data transmission. So naturally using TCP sockets will be less heavy than using HTTP. If performance is the only thing you care about then plain TCP is the best solution for you.
You may want to consider HTTP because of its ease of use and simplicity which ultimately reduces development time. If you are doing something that might be directly consumed by a browser (through an AJAX call) then you should use HTTP. For a non-modern browser to directly consume TCP connections without HTTP you would have to use Flash or Silverlight and this normally happens for rich content such as video and/or audio. However, many modern browsers now (as of 2013) support API's to access network, audio, and video resources directly via JavaScript. The only thing to consider is the usage rate of modern web browsers among your users; see caniuse.com for the latest info regarding browser compatibility.
As for benchmarks, this is the only thing I found. See page 5, it has the performance graph. Note that it doesn't really compare apples to apples since it compares the TCP/Binary data option with the HTTP/XML data option. Which begs the question: what kind of data are your services outputting? binary (video, audio, files) or text (JSON, XML, HTML)?
In general performance oriented system like those in the military or financial sectors will probably use plain TCP connections. Where as general web focused companies will opt to use HTTP and use IIS or Apache to host their services.
The question you really need an answer for is "will TCP or HTTP be faster for my application". The answer is that it depends on the nature of your application, and on the way that you use TCP and/or HTTP in your application. A generic HTTP vs TCP benchmark won't answer your question, because the chances are that the benchmark won't match your application behaviour.
In theory, an optimally designed / implemented solution using TCP will be faster than one that uses HTTP. But it may also be considerably more work to implement ... depending on the details of your application.
There are other issues that might affect your choice. For example, you are less likely to run into firewall issues if you use HTTP than if you use TCP on some random port. Another is that HTTP would make it easier to implement a load balancer between the IIS server and the backend systems.
Finally, at the end of the day it is probably more important that your system is secure, reliable, maintainable and (maybe) scalable than it is fast. A sensible strategy is to implement the simple version first, but have plans in your head for how to make it faster ... if the simple solution is too slow.
You could always benchmark it.
In general, if what you want to accomplish can be easily done over HTTP (i.e. the only reason you would otherwise think about using raw TCP is for a possible performance boost) you should probably just use HTTP. Sure, you can do socket programming, but why bother? Lots of people have spent a lot of time and effort building HTTP client libraries and servers, and they have spent waaaaaay more time optimizing and testing that code than you will ever be able to possibly spend on your TCP sockets. There are simply so many possible errors that you would have to handle, edge cases, and optimizations that can be done, that it is usually easier and safer to use a library function for HTTP.
Plus, the HTTP specs define all kinds of features (and clients/servers implement, which you get to use "for free", i.e. no extra implementation work) which makes any third-party interoperability that much easier. "Here is my URL, here are the rules for what you send, here are the rules for what I return..."
I have a Self Hosted Windows native C++ server application that I use the Casablanca C++ REST SDK code in. I can use any client C#, JavaScript, C++, cURL, basically anything that can send a POST, GET, PUT, DEL message can be used to send request messages to this self hosted windows app. Also I can use a plain browser address bar to do GET related requests using various parameters. Currently I only run this system on a private intranet so it is very fast - I haven't benchmark it against just doing raw TCP, but on a private intranet I doubt there would be even a few microseconds difference? For the convenience and ease of development and ability to expand to full blown internet app it's a dream come true. It is a dedicated system with a private protocol using small JSON packets so not certain if that fits your application needs or not? Another nice thing is this Windows application native C++ code could be ported fairly easily to run on Linux/MacOS as the Casablanca REST SDK is portable to those OSes.
I'm in the process of building a test plan for validating the security of our Flex/J2EE application. I believe we have some issues with trusting the Flex application too much, but I need to be able to quantify those issues.
The ideal way would be a way to show me making data service calls outside of the application. Are there tools or instructions for how one might go about doing this? I really don't want to find these things out after we release to our beta customers. :)
Charles is an excellent HTTP debugging proxy which can parse AMF data and display it as a tree. You can also set "breakpoints" to intercept a HTTP call and modify the AMF data in either the request or response.
http://www.charlesproxy.com/
Fiddler on Windows is great for monitoring http connections.
First, give the port on which Flex communicates to the J2EE server, then using Ethereal or Wireshark you can watch if it use an encrypted channel :-)