Path: utzoo!attcan!uunet!jarthur!usc!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!uflorida!mephisto!udel!mmdf From: archer%segin4.segin.fr@prime.com (Vincent Archer) Newsgroups: comp.os.minix Subject: Re: Crypt() Message-ID: <23590@nigel.udel.EDU> Date: 4 Jul 90 06:59:32 GMT Sender: mmdf@udel.EDU Lines: 32 In <22918@nigel.udel.EDU> archer%segin4.segin.fr@prime.com (Vincent Archer) writes: David Dick writes: > [stuff from my crypt(3) algorithm deleted] > > > I sincerely doubt that this function would be reversible. If anybody can > > think of an algorithm that (even with the salt value) gives back the > > original password, well, maths can do wonders :-) > > I don't think there is any particular reason to believe > this is a non-reversible function. I also don't understand > the distinction you are drawing between "crypters" and "scramblers". There's a simple fact that makes it a non-reversible function: more than 5000 bits of the password are used to produce a 64-bits output. So, ouf course, there's no reversibility possible, as many passwords (most of them outside of the usual ascii range) can (and will) produce the same encrypted result. This is a default in the password encoding scheme (existence of unknown but valid passwords), but it's better than the previous situation. As for crypters & Scramblers, well, a crypter can be reversed, and (given the key), you can find the original data from the destination one. A scrambler cannot be reversed; there's no way from final to initial datas. My crypt(3) is a scrambler (two inputs can give the same output), the original crypt(3) from Minix is a crypter (and a bad one, it seems). Vincent Vincent Archer | Email:archer%segin4.segin.fr@prime.com "People that are good at finding excuses are never good at anything else"