o
    )%an                     @   sX   d dl mZ d dlmZmZmZ d dlmZ d dlm	Z	 d dl
mZ G dd deZdS )	    )utils)AlreadyFinalizedUnsupportedAlgorithm_Reasons)_get_backend)CMACBackend)ciphersc                   @   s\   e Zd Z	ddejfddZdeddfddZdefd	d
ZdeddfddZ	dddZ
dS )CMACN	algorithmc                 C   sd   t |}t|tstdtjt|tjstd|| _	|| _
|d u r-| j
| j	| _d S || _d S )Nz.Backend object does not implement CMACBackend.z*Expected instance of BlockCipherAlgorithm.)r   
isinstancer   r   r   BACKEND_MISSING_INTERFACEr   BlockCipherAlgorithm	TypeError
_algorithm_backendcreate_cmac_ctx_ctx)selfr
   backendctx r   E/usr/lib/python3/dist-packages/cryptography/hazmat/primitives/cmac.py__init__   s   

zCMAC.__init__datareturnc                 C   s.   | j d u r	tdtd| | j | d S )NContext was already finalized.r   )r   r   r   _check_bytesupdate)r   r   r   r   r   r   &   s   
zCMAC.updatec                 C   s&   | j d u r	td| j  }d | _ |S )Nr   )r   r   finalize)r   digestr   r   r   r   -   s
   

zCMAC.finalize	signaturec                 C   s:   t d| | jd u rtd| jd }| _|| d S )Nr    r   )r   r   r   r   verify)r   r    r   r   r   r   r!   4   s
   
zCMAC.verifyc                 C   s*   | j d u r	tdt| j| j| j  dS )Nr   )r   r   )r   r   r	   r   r   copy)r   r   r   r   r"   <   s
   
z	CMAC.copy)NN)r   r	   )__name__
__module____qualname__r   r   r   bytesr   r   r!   r"   r   r   r   r   r	      s    
r	   N)cryptographyr   cryptography.exceptionsr   r   r   cryptography.hazmat.backendsr   'cryptography.hazmat.backends.interfacesr   cryptography.hazmat.primitivesr   objectr	   r   r   r   r   <module>   s   