From: Reshetova, Elena > Sent: 29 May 2019 11:14 .... > On related note: the current prng we have in kernel (prandom) is based on a > *very old* style of prngs, which is basically 4 linear LFSRs xored together.
I'm no expert here (apart from some knowledge of LFRS/CRC) but even adding the results of the 4 LFSR (instead of xor) will make the generator much more secure (aka computationally expensive to reverse) without affecting the randomness or repeat cycle. FWIW if you are going to merge LFRS you probably want to clock them different numbers of times (+ve or -ve) otherwise the output 'mostly' shifts one bit per clock and the same bits tend to get merged. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)