Current Path : /usr/lib/python2.7/dist-packages/Crypto/Random/Fortuna/ |
Current File : //usr/lib/python2.7/dist-packages/Crypto/Random/Fortuna/FortunaGenerator.pyc |
ó T:´Nc @ s½ d Z d d l Z e j d d k rE e j d d k rE d d l Tn d d l Td d l Z d d l m Z m Z m Z d d l m Z d d l m Z d d l Z d e f d „ ƒ YZ d S( s $Id$iÿÿÿÿNi i i ( t *( t ceil_shiftt exact_log2t exact_div( t Counter( t AESt AESGeneratorc B sm e Z d Z e j Z d Z d Z e d ƒ e d Z d „ Z d „ Z d „ Z d „ Z d „ Z d „ Z RS( s) The Fortuna "generator" This is used internally by the Fortuna PRNG to generate arbitrary amounts of pseudorandom data from a smaller amount of seed data. The output is generated by running AES-256 in counter mode and re-keying after every mebibyte (2**16 blocks) of output. i i i t i c C s t j d | j d d d d t ƒ | _ d | _ t | j ƒ | _ d | j >| j k s_ t ‚ t | j | j ƒ | _ | j | j | j k s– t ‚ | j | j | _ d S( Nt nbitsi t initial_valuei t little_endiani ( R t newt block_sizet Truet countert Nonet keyR t block_size_shiftt AssertionErrorR t key_sizet blocks_per_keyt max_blocks_per_requestt max_bytes_per_request( t self( ( sJ /usr/lib/python2.7/dist-packages/Crypto/Random/Fortuna/FortunaGenerator.pyt __init__A s ( c C sw | j d k r( t d ƒ | j | _ n | j t j | j | ƒ j ƒ ƒ | j ƒ t | j ƒ | j k ss t ‚ d S( NR ( R R t bR t _set_keyt SHAd256R t digestR t lenR ( R t seed( ( sJ /usr/lib/python2.7/dist-packages/Crypto/Random/Fortuna/FortunaGenerator.pyt reseedN s # c C s‚ | d k s t ‚ | d ?} | d @} g } x* t | ƒ D] } | j | j d ƒ ƒ q9 W| j | j | ƒ ƒ t d ƒ j | ƒ S( Ni i i t i iÿÿ i ( R t xranget appendt _pseudo_random_dataR t join( R t bytest num_full_blockst remaindert retvalt i( ( sJ /usr/lib/python2.7/dist-packages/Crypto/Random/Fortuna/FortunaGenerator.pyt pseudo_random_dataV s c C s. | | _ t j | t j d | j ƒ| _ d S( NR ( R R R t MODE_CTRR t _cipher( R R ( ( sJ /usr/lib/python2.7/dist-packages/Crypto/Random/Fortuna/FortunaGenerator.pyR c s c C s¦ d | k o | j k n s. t d ƒ ‚ n t | | j ƒ } | j | ƒ | } | j | j | j ƒ ƒ t | ƒ | k s„ t ‚ t | j ƒ | j k s¢ t ‚ | S( Ni s6 You cannot ask for more than 1 MiB of data per request( R R R R t _generate_blocksR R R R R ( R R% t num_blocksR( ( ( sJ /usr/lib/python2.7/dist-packages/Crypto/Random/Fortuna/FortunaGenerator.pyR# g s c C sÄ | j d k r t d ƒ ‚ n d | k o8 | j k n sC t ‚ g } x4 t | d ?ƒ D]"