You can control individual packets using WinDivert!

WinDivert is one of the most interesting packages I've recently come across. What WinDivert allows you to do is apply a filter to grab some subset of packets that pass through your Windows computer, and then apply some logic to the packet to maybe modify, and then drop or re-inject the packet. Here's a great diagram from this website that sums it up:


Using PyDivert, a WinDivert Python binding, we can specify the PROGRAM portion in the above diagram, which means that we can now capture whatever packets we want, change them however we want, and then either drop them or re-inject them to be sent out whenever we want.

The big sell here is that WinDivert allows you to play with packets on Windows without writing code that modifies the core operating system components that run in the kernel! The drawback is of course speed and efficiency, but for a lot of blog-post-worthy applications, we don't need that much speed and efficiency. Stay tuned for more stuff if this piqued your interest!

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