New to cryptographic, weak in math.
I have designed a PRG which consist of 33 LFSR's, each 32 bits wide.
I use one of the LFSR's as "selector", using the 5 LSB from this register to select one of the other 32 registers, from which I grab one byte and use as output. So each requested byte will thus come from one of 32 "randomly" selected registers.
My gut-feeling is that such a scheme will:
- Hide the selector register from the outside world (rendering Berlekamp-Massey useless)
- Expose an attacker to a very fast growing tree of possible combinations. (If trying to sort out from which LFSR the last byte might emerge)
As it seems to me as this is an obvious way of creating a truly messy output, it surprises me that I haven't seen it described somewhere (with a name like "Rose-Morris-Nyqvist-Yang-Goldstein-scrambler"), so my conclusion is that it must be a bad solution. (Even beside the obvious hassle of seeding 33 registers and select feedback masks).
So my question is: Why not?
/Hans