a
    còfÇ  ã                   @  st   d dl mZ d dlZd dlmZ d dlmZmZ d dlm	Z	m
Z
mZ d dlmZ G dd„ deƒZG d	d
„ d
eƒZdS )é    )ÚannotationsN)Úutils)ÚAlreadyFinalizedÚ
InvalidKey)Úconstant_timeÚhashesÚhmac)ÚKeyDerivationFunctionc                   @  sV   e Zd Zdddddddœdd„Zd	d	d
œdd„Zd	d	d
œdd„Zd	d	ddœdd„ZdS )ÚHKDFNúhashes.HashAlgorithmÚintúbytes | Noneú
typing.Any)Ú	algorithmÚlengthÚsaltÚinfoÚbackendc                 C  sB   || _ |d u rd| j j }nt d|¡ || _t| j ||ƒ| _d S )Nó    r   )Ú
_algorithmÚdigest_sizer   Ú_check_bytesÚ_saltÚ
HKDFExpandÚ_hkdf_expand)Úselfr   r   r   r   r   © r   úd/home/httpd/docs/test/DocsMgr/lib/python3.9/site-packages/cryptography/hazmat/primitives/kdf/hkdf.pyÚ__init__   s    zHKDF.__init__Úbytes©Úkey_materialÚreturnc                 C  s"   t  | j| j¡}| |¡ | ¡ S ©N)r   ÚHMACr   r   ÚupdateÚfinalize)r   r!   Úhr   r   r   Ú_extract#   s    
zHKDF._extractc                 C  s   t  d|¡ | j |  |¡¡S )Nr!   )r   Ú_check_bytesliker   Úderiver(   ©r   r!   r   r   r   r*   (   s    zHKDF.deriveÚNone©r!   Úexpected_keyr"   c                 C  s   t  |  |¡|¡st‚d S r#   ©r   Zbytes_eqr*   r   ©r   r!   r.   r   r   r   Úverify,   s    zHKDF.verify)N)Ú__name__Ú
__module__Ú__qualname__r   r(   r*   r1   r   r   r   r   r
      s
    úr
   c                   @  sT   e Zd Zddddddœdd„Zd	d	d
œdd„Zd	d	d
œdd„Zd	d	ddœdd„ZdS )r   Nr   r   r   r   )r   r   r   r   c                 C  sX   || _ d|j }||kr(td|› d�ƒ‚|| _|d u r<d}nt d|¡ || _d| _d S )Néÿ   zCannot derive keys larger than z octets.ó    r   F)r   r   Ú
ValueErrorÚ_lengthr   r   Ú_infoÚ_used)r   r   r   r   r   Ú
max_lengthr   r   r   r   2   s    

ÿzHKDFExpand.__init__r   r    c                 C  sˆ   dg}d}| j jt|ƒd  | jk rtt || j ¡}| |d ¡ | | j¡ | t|gƒ¡ | 	| 
¡ ¡ |d7 }q
d |¡d | j… S )Nr6   é   éÿÿÿÿ)r   r   Úlenr8   r   r$   r%   r9   r   Úappendr&   Újoin)r   r!   ÚoutputÚcounterr'   r   r   r   Ú_expandM   s    
zHKDFExpand._expandc                 C  s&   t  d|¡ | jrt‚d| _|  |¡S )Nr!   T)r   r)   r:   r   rC   r+   r   r   r   r*   [   s
    zHKDFExpand.deriver,   r-   c                 C  s   t  |  |¡|¡st‚d S r#   r/   r0   r   r   r   r1   c   s    zHKDFExpand.verify)N)r2   r3   r4   r   rC   r*   r1   r   r   r   r   r   1   s
    ûr   )Ú
__future__r   ÚtypingZcryptographyr   Zcryptography.exceptionsr   r   Zcryptography.hazmat.primitivesr   r   r   Z"cryptography.hazmat.primitives.kdfr	   r
   r   r   r   r   r   Ú<module>   s   "