[RFC][PATCH][BZ 2100] blowfish support in libcrypt

[Florian Weimer]

On 06/01/2017 08:59 PM, Zack Weinberg wrote:
> On Thu, Jun 1, 2017 at 2:52 PM, Florian Weimer <fweimer@redhat.com> wrote:
>> On 06/01/2017 08:44 PM, Zack Weinberg wrote:
>>> First, if we were designing from scratch today, we wouldn't have
>>> crypt(3) in the C library at all; it would make more sense to keep it
>>> with the implementations of login(1) and passwd(1), i.e. the PAM
>>> suite.  Indeed, I see that PAM independently implements the $1$
>>> md5-based format and something called "bigcrypt".  We're stuck with
>>> crypt(3), the function, in glibc forever because it's in POSIX, but I
>>> have to wonder whether it might make more sense to move _all_ of the
>>> modern password hashes into PAM and _drop_ them from glibc.
>>
>> We could build an ABI-compatible version of libcrypt from a suitable
>> cryptographic library (probably OpenSSL) because that's where all the
>> algorithms live anyway (PAM doesn't have that advantage).  There is
>> nothing glibc-specific in libcrypt, and glibc does not otherwise use it.
> 
> And libcrypt is also the only thing that cares about FIPS and NSS,
> right?  So there's a significant dependency-graph win if we kick it
> out of the glibc source tree, as well.

Yes, at least until we implement arc4random.

Florian