Peter, On Tue, Jul 31, 2012 at 3:46 PM, Peter Lind <peter.e.l...@gmail.com> wrote:
> On 31 July 2012 18:21, Anthony Ferrara <ircmax...@gmail.com> wrote: > > *snip* > > > > > Also, be aware that BCrypt only uses the first 72 characters of the > > password field. So if you use a hex encoded sha512 output, a good deal of > > entropy would be lost (almost half of it)... > > > > Seeing as the hashing function will default (at first, at least) to > bcrypt, would it be possible to add a warning if it's given an input > longer than 72 chars? Preferably make the function context-aware so > you don't get the same warning if using sha512. Otherwise I predict > that someone will do: > > $hash = password_hash($my_128_char_pepper . $password, PASSWORD_DEFAULT); > > Which obviously renders the hashing useless, as you'll be hashing the > same 72 chars over and over again. Which, currently, crypt() let's you > get away with without as much as a hiccup. > That's actually a very good idea. I'm curious though. Should we warning? Or should we sha512 hash (to bring down to 64 chars)... That's something I think would be worth reaching out to the crypt() maintainers for advice...
