social_alarm VS mlat-server

I reverse engineered a so called social alarm a bit ago. You can find it here: https://github.com/mrquincle/social_alarm

Gnuradio was also new to me. However with two HackRFs I could do the entire thing. First replay attacks. Then trying to get the code by building up a set of processing blocks. Last synthesis of the complete signal.

Very nice to do! Felt great!

I would suggest not starting in the 2.4GHz band, the protocols used there (wifi, bluetooth) are very complicated to understand. Get a rtl-sdr and start with something simpler: FM broadcast (my blogpost: https://www.abclinuxu.cz/blog/jenda/2019/11/gnu-radio-first-..., there is even an example capture you can download and replay, so you can start even without the physical radio), police radio (both analog and digital), radiosondes, weather satellites, ISM stuff - temperature sensors, garage and car remote controls, airplane multilateration (https://github.com/mutability/mlat-server)… You can do lot of stuff even with the $10 rtl-sdr, for example I have used it for multilaterating TV and radio transmitters (thesis: https://jenda.hrach.eu/dipl.pdf, unfortunately "layman's explanation" is available only as a lecture in Czech). I know people are even building radioastronomy stuff and passive radars (https://www.rtl-sdr.com/passive-radar-dual-coherent-channel-...) with rtl-sdr.

Once you have basic understanding of the topic, you can get better hardware: AirSpy (the same features as rtl-sdr, but MUCH better signal-to-noise ratio and bandwidth) or bladeRF (costly, but probably the best radio you can get now). For example I'm now building a weather radar based on bladeRF. The bladeRF has a FPGA with open-source HDL, so you can mess even with absolutely lowlevel and bleeding edge stuff.

Going back to your original question:

Most cards load firmware from a file when they are initializing (check "dmesg|grep firmware", on my machine, for example, it says it has loaded /lib/firmware/rtl_nic/rtl8153b-2.fw), you are free to modify it. However, all (or maybe almost all) wifi cards have the format of the blob completely undocumented so it would be very hard to make a modification that would allow you to transmit/receive arbitrary signals. Something similar has been achieved with GSM phones (see OsmocomBB), but it requires very complicated reverse-engineering.

Recently, there was a wifi stack released for a SDR, so the other way around: https://www.nuand.com/bladeRF-wiphy/.

I got the code from https://github.com/mutability/mlat-server does anyone know how to get it up and running any assistance would be much appreciated and extremely helpful :)