Your IP : 216.73.216.213
Bd\R41 � @ s� d Z d d l Z e j d d k rB e j d d k rB d d l Td d l Td Z d Z d Z d Z d Z d Z
d
Z d d d � Z Gd
d � d � Z
d S)z4Module with definitions common to all block ciphers.� N� � )�*� � � � � c C sK | j | � } t | � | k rA | r7 t d | � � | | } | pJ | S)zFFind a parameter in tuple and dictionary arguments a function receivesz!Parameter '%s' is specified twice)�get�len�
ValueError)�name�index�args�kwargs�defaultZparam� r �J/opt/alt/python35/lib64/python3.5/site-packages/Crypto/Cipher/blockalgo.py�
_getParameter| s
r c @ s: e Z d Z d Z d d � Z d d � Z d d � Z d S) � BlockAlgoz)Class modelling an abstract block cipher.c O s@ t d d | | d t �| _ | j | _ | j t k rc | j | | | � | _ | j j | _ n�d | _ d | _ t d d | | � | _ | j s� t
d � � | j | t t d � | j d | j d
�} t
| j � | j k r8| j | j | j d d � t d � | j d � d | j d � | _ n� t
| j � | j d k r�| j | _ | j | j t d � | j d � d | j d � | _ | j d d � | j d d � k r�t
d
� � | j d d � | _ n t
d | j | j d f � � | j | t | j | j d � d | j d
�| _ d S)N�moder r FZivr zMODE_OPENPGP requires an IV� Z segment_size� r r z%Failed integrity check for OPENPGP IVz4Length of IV must be %d or %d bytes for MODE_OPENPGP���r ���r r )r �MODE_ECBr �
block_size� MODE_OPENPGP�new�_cipherZIV�_done_first_block�_done_last_blockr �MODE_CFB�br �encrypt�
_encrypted_IV�decrypt)�self�factory�keyr r Z IV_cipherr r r �__init__� s> & zBlockAlgo.__init__c C s� | j t k r� | j t | � | j | j } | d k r� | j rW t d | j � � d | _ | t d � | } | j j | � d t | � � } n | j j | � } | j s� | j
| } d | _ | S| j j | � S)aX Encrypt data with the key and the parameters set at initialization.
The cipher object is stateful; encryption of a long block
of data can be broken up in two or more calls to `encrypt()`.
That is, the statement:
>>> c.encrypt(a) + c.encrypt(b)
is always equivalent to:
>>> c.encrypt(a+b)
That also means that you cannot reuse an object for encrypting
or decrypting other data with the same key.
This function does not perform any padding.
- For `MODE_ECB`, `MODE_CBC`, and `MODE_OFB`, *plaintext* length
(in bytes) must be a multiple of *block_size*.
- For `MODE_CFB`, *plaintext* length (in bytes) must be a multiple
of *segment_size*/8.
- For `MODE_CTR`, *plaintext* can be of any length.
- For `MODE_OPENPGP`, *plaintext* must be a multiple of *block_size*,
unless it is the last chunk of the message.
:Parameters:
plaintext : byte string
The piece of data to encrypt.
:Return:
the encrypted data, as a byte string. It is as long as
*plaintext* with one exception: when encrypting the first message
chunk with `MODE_OPENPGP`, the encypted IV is prepended to the
returned ciphertext.
r zFOnly the last chunk is allowed to have length not multiple of %d bytesTr N) r r r r r! r r# r r$ r r% )r' Z plaintext�padding_length�padded�resr r r r$ � s '! %
zBlockAlgo.encryptc C s� | j t k r� | j t | � | j | j } | d k r� | j rW t d | j � � d | _ | t d � | } | j j | � d t | � � } n | j j | � } | S| j j | � S)a� Decrypt data with the key and the parameters set at initialization.
The cipher object is stateful; decryption of a long block
of data can be broken up in two or more calls to `decrypt()`.
That is, the statement:
>>> c.decrypt(a) + c.decrypt(b)
is always equivalent to:
>>> c.decrypt(a+b)
That also means that you cannot reuse an object for encrypting
or decrypting other data with the same key.
This function does not perform any padding.
- For `MODE_ECB`, `MODE_CBC`, and `MODE_OFB`, *ciphertext* length
(in bytes) must be a multiple of *block_size*.
- For `MODE_CFB`, *ciphertext* length (in bytes) must be a multiple
of *segment_size*/8.
- For `MODE_CTR`, *ciphertext* can be of any length.
- For `MODE_OPENPGP`, *plaintext* must be a multiple of *block_size*,
unless it is the last chunk of the message.
:Parameters:
ciphertext : byte string
The piece of data to decrypt.
:Return: the decrypted data (byte string, as long as *ciphertext*).
r zFOnly the last chunk is allowed to have length not multiple of %d bytesTr N) r r r r r! r r# r r& )r' Z
ciphertextr+ r, r- r r r r& � s "! %zBlockAlgo.decryptN)�__name__�
__module__� __qualname__�__doc__r* r$ r& r r r r r � s 3 ;r )r1 �sys� version_infoZCrypto.Util.py21compatZCrypto.Util.py3compatr ZMODE_CBCr" ZMODE_PGPZMODE_OFBZMODE_CTRr r r r r r r �<module> s &