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    [e!                     @   s|   d dl mZ d dlmZmZmZ d dlmZ d dlm	Z	 e
eje
eje
eje
ejG dd deZdS )    )utils)
InvalidTagUnsupportedAlgorithm_Reasons)ciphers)modesc                   @   sx   e Zd ZdZdZdZdd ZeedddZee	dd	d
Z
edddZeedddZeddddZedZdS )_CipherContext   r   i?c                 C   s  || _ || _|| _|| _d | _t| jtjr<| jjd | _	nd| _	| j j
 }| j j|| j j
j}| j j}z|t|t|f }W n4 tk
r   td|j|r|jn|tjY nX || j ||}|| j jjkrd|}	|d k	r|	d|7 }	|	d| j  7 }	t|	tjt|tjr8| j j|j}
njt|tjrX| j j|j}
nJt|tjrx| j j|j }
n*t|tjr| j j|j }
n
| j jj}
| j j
!||| j jj| j jj| j jj|}| j "|dk | j j
#|t$|j%}| j "|dk t|tj&r| j j
'|| j j
j(t$|
| j jj}| j "|dk |j)d k	r| j j
'|| j j
j*t$|j)|j)}| j "|dk |j)| _| j j
!|| j jj| j jj| j j|j%|
|}| j "|dk | j j
+|d || _,d S )N   r	   z6cipher {} in {} mode is not supported by this backend.zcipher {0.name} zin {0.name} mode z_is not supported by this backend (Your version of OpenSSL may be too old. Current version: {}.)r   )-_backendZ_cipher_mode
_operation_tag
isinstancer   ZBlockCipherAlgorithm
block_size_block_size_bytes_libZEVP_CIPHER_CTX_new_ffigcZEVP_CIPHER_CTX_freeZ_cipher_registrytypeKeyErrorr   formatnamer   ZUNSUPPORTED_CIPHERNULLZopenssl_version_textr   ZModeWithInitializationVectorfrom_bufferZinitialization_vectorZModeWithTweakZtweakZModeWithNoncenonceZEVP_CipherInit_exopenssl_assertZEVP_CIPHER_CTX_set_key_lengthlenkeyGCMEVP_CIPHER_CTX_ctrlZEVP_CTRL_AEAD_SET_IVLENtagEVP_CTRL_AEAD_SET_TAGZEVP_CIPHER_CTX_set_padding_ctx)selfbackendciphermodeZ	operationctxregistryadapterZ
evp_ciphermsgZiv_nonceres r-   n/var/www/html/services/stratfitenv/lib/python3.8/site-packages/cryptography/hazmat/backends/openssl/ciphers.py__init__   s      


 z_CipherContext.__init__)datareturnc                 C   s2   t t|| j d }| ||}t|d | S )Nr	   )	bytearrayr   r   update_intobytes)r$   r0   bufnr-   r-   r.   updatey   s    z_CipherContext.updatec                 C   s   t |}t ||| j d k r:tdt || j d d}d}| jjd}| jj|}| jj|}||kr|| }	|| }
t| j	|| }| jj
| j|	||
|}| j|dk ||7 }||d 7 }ql|S )Nr	   z1buffer must be at least {} bytes for this payloadr   int *)r   r   
ValueErrorr   r   r   newr   min_MAX_CHUNK_SIZEr   EVP_CipherUpdater#   r   )r$   r0   r5   Ztotal_data_lenZdata_processedZ	total_outoutlenZ
baseoutbufZ	baseinbufZoutbufZinbufZinlenr,   r-   r-   r.   r3   ~   s6        z_CipherContext.update_into)r1   c                 C   sh  | j | jkr,t| jtjr,| jd kr,td| jj	
d| j}| jj	
d}| jj| j||}|dkr| j }|st| jtjrt| jj|d | jjj| jjj|d tdt| jtjr.| j | jkr.| jj	
d| j}| jj| j| jjj| j|}| j|dk | jj	|d d  | _| jj| j}| j|dk | jj	|d |d  S )Nz4Authentication tag must be provided when decrypting.zunsigned char[]r8   r   )errorszFThe length of the provided data is not a multiple of the block length.r	   )r   _DECRYPTr   r   r   ZModeWithAuthenticationTagr!   r9   r   r   r:   r   r   ZEVP_CipherFinal_exr#   Z_consume_errorsr   r   r   Z_lib_reason_matchZERR_LIB_EVPZ'EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH_ENCRYPTr    ZEVP_CTRL_AEAD_GET_TAGbufferr   ZEVP_CIPHER_CTX_reset)r$   r5   r>   r,   r?   Ztag_bufr-   r-   r.   finalize   sZ    


 z_CipherContext.finalize)r!   r1   c                 C   s`   t || jjk r"td| jj| jj| j| jjj	t ||}| j
|dk || _|  S )Nz.Authentication tag must be {} bytes or longer.r   )r   r   Z_min_tag_lengthr9   r   r   r   r    r#   r"   r   r   rC   )r$   r!   r,   r-   r-   r.   finalize_with_tag   s       z _CipherContext.finalize_with_tagNc                 C   sN   | j jd}| j j| j| j jj|| j j|t|}| j 	|dk d S )Nr8   r   )
r   r   r:   r   r=   r#   r   r   r   r   )r$   r0   r>   r,   r-   r-   r.   authenticate_additional_data   s    z+_CipherContext.authenticate_additional_datar   )__name__
__module____qualname__rA   r@   r<   r/   r4   r7   intr3   rC   rD   rE   r   Zread_only_propertyr!   r-   r-   r-   r.   r      s   d3r   N)Zcryptographyr   Zcryptography.exceptionsr   r   r   Zcryptography.hazmat.primitivesr   Z&cryptography.hazmat.primitives.ciphersr   Zregister_interfaceZCipherContextZAEADCipherContextZAEADEncryptionContextZAEADDecryptionContextobjectr   r-   r-   r-   r.   <module>   s   



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