This is an implementation of a password hashing algorithm, provided
via the crypt(3) and a reentrant interface.  It is compatible with
OpenBSD bcrypt.c (version 2a) by Niels Provos and David Mazieres.

I've placed this code in the public domain.  Please, see the comment
in crypt_blowfish.c for more information.

You can use the provided routines in your own packages, or link them
into a C library.  I've provided hooks for linking into GNU libc 2.1,
but it shouldn't be too hard to get this into another library.  Note
that simply adding this code into your libc is probably not enough to
make your system use the new password hashing algorithm.  Changes to
passwd(1), PAM modules, or whatever else your system uses will likely
be needed as well.  These are not (yet?) a part of this package.

Instructions on using the routines in one of the two common ways are
given below.  It is recommended that you test the routines on your
system before you start.  Type "make check" or "make check_threads"
(if you have the POSIX threads library), then "make clean".


1. Using the routines in your programs.

The available interfaces are in ow-crypt.h, and this is the file you
should include.  You won't need crypt.h.  When linking, add all of the
C files and x86.S (you can compile and link it even on a non-x86, it
will produce no code in this case).


2. Building the routines into GNU C library, version 2.1.

Extract the library sources and the crypt add-on as usual.  Apply the
patch provided in this package.  Enter crypt/sysdeps/unix, and rename
crypt.h to gnu-crypt.h within that directory.  Copy C sources, header
and assembly (x86.S) files from this package in there as well (be sure
you don't overwrite the Makefile).  Configure, build, and install the
library as usual.

Programs that want to use the provided interfaces will need to include
crypt.h (but not ow-crypt.h directly).  By default, prototypes for the
new routines aren't defined (but the extra functionality of crypt(3)
is indeed available).  You need to define _OW_SOURCE to obtain the new
routines as well.

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$Id: README.bcrypt,v 1.1 2003/10/16 06:49:21 kukuk Exp $
