derive¶

    $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 <https://tools.ietf.org/html/rfc2898#section-4.1> a random salt of at least 8 octets. If you need a cryptographically strong salt, consider Crypt::URandom.

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.

derive_hex¶

Works just like "derive" but outputs a hex string.

verify¶

    $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".

verify_hex¶

Works just like "verify" but the derived key must be a hex string (without a leading "0x").

digest_fcn¶

    ($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.

hmac¶

    $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.

Bugs / Feature Requests¶

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.

Source Code¶

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