U
    [eu                     @   sF   d dl mZ d dlmZmZmZ d dlmZmZ G dd dej	Z
dS )    )utils)InvalidSignatureUnsupportedAlgorithm_Reasons)constant_timehashesc                   @   sf   e Zd ZdeejdddZedZ	d dddZ
edd	d
dZedddZeddddZdS )_HMACContextN)key	algorithmc                 C   s   || _ || _|d kr| jj }| j|| jjjk | jj|| jjj}| j	|}|| jjjkrzt
d|jtj| jj|}| jj||t||| jjj}| j|dk || _|| _d S )Nz*{} is not a supported hash on this backendr   )
_algorithm_backend_libHMAC_CTX_newopenssl_assert_ffiNULLgcHMAC_CTX_freeZ_evp_md_from_algorithmr   formatnamer   ZUNSUPPORTED_HASHfrom_bufferZHMAC_Init_exlen_ctx_key)selfbackendr	   r
   ctxZevp_mdZkey_ptrres r   k/var/www/html/services/stratfitenv/lib/python3.8/site-packages/cryptography/hazmat/backends/openssl/hmac.py__init__   s2        z_HMACContext.__init__r   )returnc                 C   sp   | j j }| j || j jjk | j j|| j jj}| j j|| j	}| j |dk t
| j | j| j|dS )Nr   )r   )r   r   r   r   r   r   r   r   ZHMAC_CTX_copyr   r   r   r
   )r   Z
copied_ctxr   r   r   r   copy-   s        z_HMACContext.copy)datar!   c                 C   s:   | j j|}| j j| j|t|}| j |dk d S )Nr   )r   r   r   r   ZHMAC_Updater   r   r   )r   r#   Zdata_ptrr   r   r   r   update9   s    z_HMACContext.updatec                 C   sz   | j jd| j jj}| j jd}| j j| j||}| j |dk | j |d | jj	k | j j
|d |d  S )Nzunsigned char[]zunsigned int *r   )r   r   newr   ZEVP_MAX_MD_SIZEZ
HMAC_Finalr   r   r
   digest_sizebuffer)r   bufZoutlenr   r   r   r   finalize>   s     z_HMACContext.finalize)	signaturer!   c                 C   s    |   }t||stdd S )NzSignature did not match digest.)r)   r   Zbytes_eqr   )r   r*   digestr   r   r   verifyH   s    z_HMACContext.verify)N)__name__
__module____qualname__bytesr   ZHashAlgorithmr    r   Zread_only_propertyr
   r"   r$   r)   r,   r   r   r   r   r      s     

r   N)Zcryptographyr   Zcryptography.exceptionsr   r   r   Zcryptography.hazmat.primitivesr   r   ZHashContextr   r   r   r   r   <module>   s   