I am working to understand a system which saves a few bytes of data together with what appears to be a single checksum byte that provides a very naive guarantee that the data has not been tampered with. My current task is to understand how this checksum is being calculated.
I cannot currently post any specific data, but I do have reason to believe the checksum calculation is very easy to compute. I also know for a fact that it receives no more than 6 bytes of data as input, and quite possibly as little as one byte.
Given that I have a table of several samples of data bytes + checksums, is there a formal process to reverse engineer this checksum, or do I have to rely on simple logic deduction from the known facts that I have?