5 ms·
Would a CSPRNG be at all an improvement with only a 32 bit seed? Couldn't you still brute force it?
by aidenn0 3y ago
Would a CSPRNG be at all an improvement with only a 32 bit seed? Couldn't you still brute force it?
- ryanatdistrust 3y agoThat is correct, you still have 2^32 permutations of possible values.
- marginalia_nu 3y agoGiven it's seeded with system time, depending on the resolution, that may in practice be as low as tens of thousands of possible values (as in time(2) )
- ryanatdistrust 3y ago2^32 is still incredibly small for crypto and is inexcusable.
- nullc 3y agoA fact which was unambiguously well known to the authors prior to the report: https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2022-July/020652.html https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2022...
- a-dub 3y agoi think the bigger problem is that the seed is easily guessed or found, so all the output can be regenerated. so it's not even 32 bits of entropy, it's some tiny fraction of that. (system times for a few years interval)
- ryanatdistrust 3y agoAs discussed elsethread, it used the lower bits of the time value, so while there is is a fraction of the 2^32 space due to precision loss in the OS time calculations, it is not as simple as "between when this software was released and now, in seconds".