PBKDF2::Tiny - Minimalist PBKDF2 (RFC 2898) with HMAC-SHA1 or HMAC-SHA2
version 0.005
use PBKDF2::Tiny qw/derive verify/;
my $dk = derive( 'SHA-1', $pass, $salt, $iters );
if ( verify( $dk, 'SHA-1', $pass, $salt, $iters ) ) {
# password is correct
}
This module provides an RFC 2898
compliant PBKDF2 implementation using HMAC-SHA1 or HMAC-SHA2 in under 100 lines
of code. If you are using Perl 5.10 or later, it uses only core Perl modules.
If you are on an earlier version of Perl, you need the Digest::SHA manpage or
the Digest::SHA::PurePerl manpage.
All documented functions are optionally exported. No functions are exported by default.
$dk = derive( $type, $password, $salt, $iterations, $dk_length )
The derive function outputs a binary string with the derived key.
The first argument indicates the digest function to use. It must be one
of: SHA-1, SHA-224, SHA-256, SHA-384, or SHA-512.
If a password or salt are not provided, they default to the empty string, so
don't do that! RFC 2898 recommends a random salt of at
least 8 octets. If you need a cryptographically strong salt, consider
the Crypt::URandom manpage.
The password and salt should encoded as octet strings. If not (i.e. if
Perl's internal 'UTF8' flag is on), then an exception will be thrown.
The number of iterations defaults to 1000 if not provided. If the derived
key length is not provided, it defaults to the output size of the digest
function.
Works just like derive but outputs a hex string.
$bool = verify( $dk, $type, $password, $salt, $iterations, $dk_length );
The verify function checks that a given derived key (in binary form) matches
the password and other parameters provided using a constant-time comparison
function.
The first parameter is the derived key to check. The remaining parameters
are the same as for derive.
Works just like verify but the derived key must be a hex string (without a
leading ``0x'').
($fcn, $block_size, $digest_length) = digest_fcn('SHA-1');
$digest = $fcn->($data);
This function is used internally by PBKDF2::Tiny, but made available in case
it's useful to someone.
Given one of the valid digest types, it returns a function reference that
digests a string of data. It also returns block size and digest length for that
digest type.
$key = $digest_fcn->($key) if length($key) > $block_size;
$hmac = hmac( $data, $key, $digest_fcn, $block_size );
This function is used internally by PBKDF2::Tiny, but made available in case
it's useful to someone.
The first two arguments are the data and key inputs to the HMAC function. Both
should be encoded as octet strings, as underlying HMAC/digest functions may
croak or may give unexpected results if Perl's internal UTF-8 flag is on.
Note: if the key is longer than the digest block size, it must be
preprocessed using the digesting function.
The third and fourth arguments must be a digesting code reference (from
digest_fcn) and block size.
Please report any bugs or feature requests through the issue tracker
at https://github.com/dagolden/PBKDF2-Tiny/issues.
You will be notified automatically of any progress on your issue.
This is open source software. The code repository is available for
public review and contribution under the terms of the license.
https://github.com/dagolden/PBKDF2-Tiny
git clone https://github.com/dagolden/PBKDF2-Tiny.git
David Golden <dagolden@cpan.org>
This software is Copyright (c) 2014 by David Golden.
This is free software, licensed under:
The Apache License, Version 2.0, January 2004
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