Tim Peters added the comment: > Searching github pulls up a number of results of people > calling it, but I haven't looked through them to see > how/why they're calling it.
Sorry, I don't know what "it" refers to. Surely not to a program exposing the output of .getstate()?! Regardless, there was a long discussion about the `secrets` module at the time, and nobody found any real code vulnerable to the approaches in the PHP paper under Python 3 (contrived code, certainly - that's easy). Again, exploiting lame seeding alone sufficed to crack most of their examples, and Python's use of urandom() for seeding eliminated that approach (in Python 2 too). Examples potentially vulnerable to state equation-solving were "just like" what the PHP coders rolled by hand: uses of things like .choice() and .randrange() to build "random" strings (passwords, session tokens, ...), from relatively small alphabets. The smaller the alphabet, the more resistant Python 3 is to this approach, because the more likely ._randbelow() will invisibly skip over MT outputs. For a while an incorrect claim was mistakenly accepted: that when len(alphabet) was a power of 2, choice(alphabet) made an always-known number of MT calls. If that were true, the equation solver could deduce the state quickly in such cases, which are relatively common. But it's false - ._randbelow() is actually _most_ likely to skip over MT outputs when it's making a choice from a power-of-2 number of possibilities. That's not obvious from a glance at the code. I remain -1 on making seeding "dumb" again. But I don't care whether urandom() returns low-quality bytes in the boot-time edge cases people are upset about. They're still likely to be "better" than anything spun out of stuff like time.time(). ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue27272> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
