How to intercept packets sent by an application and check their header and content?

c# packet-sniffers sniffing
Jax picture Jax · Sep 15, 2012 · Viewed 41.1k times · Source

I'd like to know how can I intercept packets sent by a certain application and then to check what those packets contain. I need some advice what to do because I've never done such a thing and I want to learn by myself.

Answer

Harsh Baid picture Harsh Baid · Sep 15, 2012

Pcap.Net

Pcap.Net is a .NET wrapper for WinPcap written in C++/CLI and C#. It Features almost all WinPcap features and includes a packet interpretation framework.

SharpPcap

SharpPcap is a cross-platform packet capture framework for the .NET environment, based on the famous pcap / WinPcap libraries. It provides an API for capturing, injecting, analyzing and building packets using any .NET language such as C# and VB.NET.

Comparision of Pcap.Net and SharpPcap

Wireshark

It is used for network troubleshooting, analysis, software and communications protocol development, and education. And I think it is the most versatile packet sniffer I used till now.

Fiddler

Fiddler is a Web Debugging Proxy which logs all HTTP(S) traffic between your computer and the Internet. Fiddler allows you to inspect traffic, set breakpoints, and "fiddle" with incoming or outgoing data. Fiddler includes a powerful event-based scripting subsystem, and can be extended using any .NET language. Recently Fiddler has been overtook by Telerik. But it is still free AFAIK.

Related questions

Don't know why I'm getting Error Code 10022 (Invalid Argument) when setting socket options in my C# sniffer

I'm writing a packet sniffer as an exercise in learning .Net 4 socket development on in C#. My goal is to sniff IP packets coming in and out out my computer. My problem is that I'm getting error code 10022, invalid argument, …

Read More
c# - how to sniff packets in an app without relying on WinPCap?

BACKGROUND: I now understand how to write a C# application that can monitor packets going in/out of the network card on the PC the application is running on. The approach I know relies on http://www.winpcap.org/ being …

Read More
Network Sniffer in C#

Recently I completed my network sniffer for the company that I am currently working with. I want to know: Is there any way to edit the captured packets before reaching the destination? (UDP/TCP) Is there any other procedure to …

Read More