NAME

       Crypt::KeyDerivation - PBKDF1, PBKDF2 and HKDF key derivation functions

SYNOPSIS

         ### PBKDF1/2
         $derived_key1 = pbkdf1($password, $salt, $iteration_count, $hash_name, $len);
         $derived_key2 = pbkdf2($password, $salt, $iteration_count, $hash_name, $len);

         ### HKDF & co.
         $derived_key3 = hkdf($keying_material, $salt, $hash_name, $len, $info);
         $prk  = hkdf_extract($keying_material, $salt, $hash_name);
         $okm1 = hkdf_expand($prk, $hash_name, $len, $info);

DESCRIPTION

       Provides an interface to Key derivation functions:

       •   PBKDF1 and PBKDF according to PKCS#5 v2.0 <https://tools.ietf.org/html/rfc2898>

       •   HKDF (+ related) according to <https://tools.ietf.org/html/rfc5869>

FUNCTIONS

   pbkdf1
       BEWARE: if you are not sure, do not use "pbkdf1" but rather choose "pbkdf2".

         $derived_key = pbkdf1($password, $salt, $iteration_count, $hash_name, $len);
         #or
         $derived_key = pbkdf1($password, $salt, $iteration_count, $hash_name);
         #or
         $derived_key = pbkdf1($password, $salt, $iteration_count);
         #or
         $derived_key = pbkdf1($password, $salt);

         # $password ......... input keying material  (password)
         # $salt ............. salt/nonce (expected length: 8)
         # $iteration_count .. optional, DEFAULT: 5000
         # $hash_name ........ optional, DEFAULT: 'SHA256'
         # $len .............. optional, derived key len, DEFAULT: 32

   pbkdf2
         $derived_key = pbkdf2($password, $salt, $iteration_count, $hash_name, $len);
         #or
         $derived_key = pbkdf2($password, $salt, $iteration_count, $hash_name);
         #or
         $derived_key = pbkdf2($password, $salt, $iteration_count);
         #or
         $derived_key = pbkdf2($password, $salt);

         # $password ......... input keying material (password)
         # $salt ............. salt/nonce
         # $iteration_count .. optional, DEFAULT: 5000
         # $hash_name ........ optional, DEFAULT: 'SHA256'
         # $len .............. optional, derived key len, DEFAULT: 32

   hkdf
         $okm2 = hkdf($password, $salt, $hash_name, $len, $info);
         #or
         $okm2 = hkdf($password, $salt, $hash_name, $len);
         #or
         $okm2 = hkdf($password, $salt, $hash_name);
         #or
         $okm2 = hkdf($password, $salt);

         # $password ... input keying material (password)
         # $salt ....... salt/nonce, if undef defaults to HashLen zero octets
         # $hash_name .. optional, DEFAULT: 'SHA256'
         # $len ........ optional, derived key len, DEFAULT: 32
         # $info ....... optional context and application specific information, DEFAULT: ''

   hkdf_extract
         $prk  = hkdf_extract($password, $salt, $hash_name);
         #or
         $prk  = hkdf_extract($password, $salt, $hash_name);

         # $password ... input keying material (password)
         # $salt ....... salt/nonce, if undef defaults to HashLen zero octets
         # $hash_name .. optional, DEFAULT: 'SHA256'

   hkdf_expand
         $okm = hkdf_expand($pseudokey, $hash_name, $len, $info);
         #or
         $okm = hkdf_expand($pseudokey, $hash_name, $len);
         #or
         $okm = hkdf_expand($pseudokey, $hash_name);
         #or
         $okm = hkdf_expand($pseudokey);

         # $pseudokey .. input keying material
         # $hash_name .. optional, DEFAULT: 'SHA256'
         # $len ........ optional, derived key len, DEFAULT: 32
         # $info ....... optional context and application specific information, DEFAULT: ''