(03-26-2021, 12:54 PM)ingol Wrote: I have only the sniffer capture data, they are all in hex-format, since it is correct for me to make this command ?
This is an exchange of data between devices with a checksum (CRC32), I need to understand how it is calculated
I have already tested all available online calculators CRC32 - no result.
well i think no, unless you have a "known" message and its processed data from your sniffing data
given your infos the crc is maybe only for the communicating devices to verify, that the transmitted data is correct, the crc part of the transmission can be anything crc(data) mixed with an "unknown" salt the two devices made up earlier
device a sends paket [data:crc], the kind of data transmitted can be anyting (what for a device)
device b recieves paket with[data:crc] and checks whether crc(data) + unkwon salt? equals crc, if yes -> packet recieved with no errors, if not -> either the data part or the crc part of the message was corrupted on transmission, anyhow the paket is invalid and will be be dropped/requested again due to the invalid data
so if you not really know what data these devices sending/recieving and how this communication works, is the data encrypted? is the data/crc salted? what kind of "plain" data do you expect to get? dont think that anyone can help