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    (Q^                     @   s,  d Z ddlZddlZddlZddlZddlZddlmZ ddlm	Z	 ddl
mZ ddl
mZ ddl
mZ dd	l
mZ dd
l
mZ ddl
mZ dZdZe	djZeeddZe Zedd ejjejjfD ZeddfddZeddfddZdd Zdd Z dd Z!dd Z"d&d d!Z#d"d# Z$d$d% Z%dS )'z
    werkzeug.security
    ~~~~~~~~~~~~~~~~~

    Security related helpers such as secure password hashing tools.

    :copyright: 2007 Pallets
    :license: BSD-3-Clause
    N)SystemRandom)Struct   )izip)PY2)
range_type)	text_type)to_bytes)	to_nativeZ>abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789iI z>Icompare_digestc                 c   s   | ]}|d kr|V  qdS ))N/N .0sepr   r   7/tmp/pip-install-bd4o36v9/Werkzeug/werkzeug/security.py	<genexpr>    s     r   c                 C   s    t | ||||}tt|dS )a)  Like :func:`pbkdf2_bin`, but returns a hex-encoded string.

    .. versionadded:: 0.9

    :param data: the data to derive.
    :param salt: the salt for the derivation.
    :param iterations: the number of iterations.
    :param keylen: the length of the resulting key.  If not provided,
                   the digest size will be used.
    :param hashfunc: the hash function to use.  This can either be the
                     string name of a known hash function, or a function
                     from the hashlib module.  Defaults to sha256.
    	hex_codec)
pbkdf2_binr
   codecsencode)datasalt
iterationskeylenhashfuncrvr   r   r   
pbkdf2_hex%   s    r   c                 C   sJ   |sd}t | } t |}t|r4| }t|dd}n|}t|| |||S )a  Returns a binary digest for the PBKDF2 hash algorithm of `data`
    with the given `salt`. It iterates `iterations` times and produces a
    key of `keylen` bytes. By default, SHA-256 is used as hash function;
    a different hashlib `hashfunc` can be provided.

    .. versionadded:: 0.9

    :param data: the data to derive.
    :param salt: the salt for the derivation.
    :param iterations: the number of iterations.
    :param keylen: the length of the resulting key.  If not provided
                   the digest size will be used.
    :param hashfunc: the hash function to use.  This can either be the
                     string name of a known hash function or a function
                     from the hashlib module.  Defaults to sha256.
    sha256nameN)r	   callablegetattrhashlibpbkdf2_hmac)r   r   r   r   r   Z
_test_hash	hash_namer   r   r   r   9   s    r   c                 C   s   t | tr| d} t |tr(|d}tdk	r:t| |S t| t|krNdS d}trt| |D ]\}}|t|t|A O }q`n t| |D ]\}}|||A O }q|dkS )zThis function compares strings in somewhat constant time.  This
    requires that the length of at least one string is known in advance.

    Returns `True` if the two strings are equal, or `False` if they are not.

    .. versionadded:: 0.7
    utf-8NFr   )
isinstancer   r   _builtin_safe_str_cmplenr   r   ord)abr   xyr   r   r   safe_str_cmpZ   s    




r.   c                 C   s(   | dkrt dddd t| D S )zAGenerate a random string of SALT_CHARS with specified ``length``.r   zSalt length must be positive c                 s   s   | ]}t tV  qd S N)_sys_rngchoice
SALT_CHARS)r   _r   r   r   r   |   s     zgen_salt.<locals>.<genexpr>)
ValueErrorjoinr   )lengthr   r   r   gen_saltx   s    r8   c           	      C   s   | dkr|| fS t |tr$|d}| dr| dd d}t|dkrTtd|d	} |rrt|d	 pnd	ptt	}d
}d| |f }nd}| }|r|stdt
|||| d}n>|rt |tr|d}t||| }| }nt| | }||fS )zInternal password hash helper.  Supports plaintext without salt,
    unsalted and salted passwords.  In case salted passwords are used
    hmac is used.
    plainr%   zpbkdf2:   N:)r      z&Invalid number of arguments for PBKDF2r   Tzpbkdf2:%s:%dFzSalt is required for PBKDF2)r   )r&   r   r   
startswithsplitr(   r5   popintDEFAULT_PBKDF2_ITERATIONSr   _create_mac	hexdigestr"   new)	methodr   passwordargsr   Z	is_pbkdf2actual_methodr   macr   r   r   _hash_internal   s2    






rJ   c                    s8   t  rt| | S d fdd	}||_t| ||S )N    c                    s   t  | S r0   )r"   rD   )drE   r   r   r      s    z_create_mac.<locals>.hashfunc)rK   )r    hmacHMAC__call__)keymsgrE   r   r   rM   r   rB      s
    rB   pbkdf2:sha256   c                 C   s2   |dkrt |nd}t||| \}}d|||f S )a  Hash a password with the given method and salt with a string of
    the given length. The format of the string returned includes the method
    that was used so that :func:`check_password_hash` can check the hash.

    The format for the hashed string looks like this::

        method$salt$hash

    This method can **not** generate unsalted passwords but it is possible
    to set param method='plain' in order to enforce plaintext passwords.
    If a salt is used, hmac is used internally to salt the password.

    If PBKDF2 is wanted it can be enabled by setting the method to
    ``pbkdf2:method:iterations`` where iterations is optional::

        pbkdf2:sha256:80000$salt$hash
        pbkdf2:sha256$salt$hash

    :param password: the password to hash.
    :param method: the hash method to use (one that hashlib supports). Can
                   optionally be in the format ``pbkdf2:<method>[:iterations]``
                   to enable PBKDF2.
    :param salt_length: the length of the salt in letters.
    r9   r/   z%s$%s$%s)r8   rJ   )rF   rE   Zsalt_lengthr   hrH   r   r   r   generate_password_hash   s    rV   c                 C   s:   |  ddk rdS | dd\}}}tt|||d |S )a  check a password against a given salted and hashed password value.
    In order to support unsalted legacy passwords this method supports
    plain text passwords, md5 and sha1 hashes (both salted and unsalted).

    Returns `True` if the password matched, `False` otherwise.

    :param pwhash: a hashed string like returned by
                   :func:`generate_password_hash`.
    :param password: the plaintext password to compare against the hash.
    $r<   Fr   )countr>   r.   rJ   )ZpwhashrF   rE   r   Zhashvalr   r   r   check_password_hash   s    rY   c                    sp   | g}|D ]Z  dkr t   t fddtD sTtj sT dksT drZ dS |  q
t j	| S )a2  Safely join zero or more untrusted path components to a base
    directory to avoid escaping the base directory.

    :param directory: The trusted base directory.
    :param pathnames: The untrusted path components relative to the
        base directory.
    :return: A safe path, otherwise ``None``.
    r/   c                 3   s   | ]}| kV  qd S r0   r   r   filenamer   r   r      s     zsafe_join.<locals>.<genexpr>z..z../N)
	posixpathnormpathany_os_alt_sepsospathisabsr=   appendr6   )	directoryZ	pathnamespartsr   rZ   r   	safe_join   s    	

rf   )rS   rT   )&__doc__r   r"   rN   r`   r\   randomr   structr   _compatr   r   r   r   r	   r
   r3   rA   packZ	_pack_intr!   r'   r1   listra   r   altsepr_   r   r   r.   r8   rJ   rB   rV   rY   rf   r   r   r   r   <module>   sH   	
  
  
!%
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