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Editing: randbytes.cpython-38.pyc
U W[w � @ s� d Z ddlmZmZ ddlZddlZddlZddlZddlm Z e edd�Z e rXe j Zndd� ZG dd � d e�ZG d d � d e�ZG d d � d e�Ze� ZejZejZ[ddd gZdS )zQ Cryptographically secure random implementation, with fallback on normal random. � )�division�absolute_importN)�_PY3� getrandbitsc C s | � d�S )N�hex)�decode)�hexBytes� r �:/usr/lib/python3/dist-packages/twisted/python/randbytes.py�_fromhex s r c @ s e Zd ZdZdS )�SecureRandomNotAvailablezD Exception raised when no secure random algorithm is found. N��__name__� __module__� __qualname__�__doc__r r r r r s r c @ s e Zd ZdZdS )�SourceNotAvailablezQ Internal exception used when a specific random source is not available. Nr r r r r r s r c @ sf e Zd ZdZdZeZdd� Zddd�Zdd � Ze rBe j Z d d � Z nej Z d d � Z e d d �Zdd� ZdS )� RandomFactoryz� Factory providing L{secureRandom} and L{insecureRandom} methods. You shouldn't have to instantiate this class, use the module level functions instead: it is an implementation detail and could be removed or changed arbitrarily. r c C s@ z t �|�W S ttfk r: } z t|��W 5 d}~X Y nX dS )zO Wrapper around C{os.urandom} that cleanly manage its absence. N)�os�urandom�AttributeError�NotImplementedErrorr )�self�nbytes�er r r � _osUrandom5 s zRandomFactory._osUrandomFc C sL z | � |�W S tk r Y nX |r@tjdtdd� | �|�S td��dS )ak Return a number of secure random bytes. @param nbytes: number of bytes to generate. @type nbytes: C{int} @param fallback: Whether the function should fallback on non-secure random or not. Default to C{False}. @type fallback: C{bool} @return: a string of random bytes. @rtype: C{str} zPurandom unavailable - proceeding with non-cryptographically secure random source� )�category� stacklevelz!No secure random source availableN)r r �warnings�warn�RuntimeWarning�insecureRandomr )r r Zfallbackr r r � secureRandom? s � zRandomFactory.secureRandomc C s< | j dk r0| � |d �}d|d | }t|�S td��dS )z3 Wrapper around C{os.getrandbits}. N� z%%0%dxr z#random.getrandbits is not available)r r r )r r �nr r r r � _randBits\ s zRandomFactory._randBitsc s d� � fdd�t|�D ��S )�> Wrapper around the C{random} module. � c s g | ]}t t�� j�g��qS r )�bytes�random�choice�_BYTES��.0�i�r r r � <listcomp>m s �-RandomFactory._randModule.<locals>.<listcomp>��join�range�r r r r0 r � _randModulei s �zRandomFactory._randModulec s d� � fdd�t|�D ��S )r' r( c s g | ]}t �� j��qS r )r* r+ r, r- r0 r r r1 u s r2 r3 r6 r r0 r r7 q s �r( c C s8 dD ].}zt | |�|�W S tk r0 Y qX qdS )z� Return a number of non secure random bytes. @param nbytes: number of bytes to generate. @type nbytes: C{int} @return: a string of random bytes. @rtype: C{str} )r& r7 N)�getattrr )r r �srcr r r r" { s z RandomFactory.insecureRandomN)F)r r r r Z randomSourcesr r r# r& r r) � maketransZ _maketransr7 �stringr, r" r r r r r & s r r# r" )r Z __future__r r r r r* r; Ztwisted.python.compatr r8 r r) �fromhexr � RuntimeErrorr r �objectr �factoryr# r" �__all__r r r r �<module> s g
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