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 m Z d Z d Z e	 d ƒ j Z e e d d ƒ Z e ƒ  Z e d d „  e j j e j j g Dƒ ƒ Z e d d d d „ Z e d d d d „ Z d d „  Z d d „  Z  d d „  Z! d d „  Z" d 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
é    N)ÚSystemRandom)ÚStructé   )Úizip)ÚPY2)Ú
range_type)Ú	text_type)Úto_bytes)Ú	to_nativeZ>abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789iðI z>IÚcompare_digestc             c   s!   |  ] } | d k r | Vq d  S)Nú/)Nr   © )Ú.0Úsepr   r   ú5/tmp/pip-build-5gj8f0j9/Werkzeug/werkzeug/security.pyú	<genexpr>!   s    r   c             C   s.   t  |  | | | | ƒ } t t j | d ƒ ƒ 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.
    Ú	hex_codec)Ú
pbkdf2_binr
   ÚcodecsÚencode)ÚdataÚsaltÚ
iterationsÚkeylenÚhashfuncÚrvr   r   r   Ú
pbkdf2_hex%   s    r   c             C   sm   | s d } t  |  ƒ }  t  | ƒ } t | ƒ rN | ƒ  } t | d d ƒ } n | } t j | |  | | | ƒ S)aò  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.
    Úsha256ÚnameN)r	   ÚcallableÚgetattrÚhashlibÚpbkdf2_hmac)r   r   r   r   r   Z
_test_hashÚ	hash_namer   r   r   r   9   s    	r   c             C   sò   t  |  t ƒ r |  j d ƒ }  t  | t ƒ r< | j d ƒ } t d k	 rU t |  | ƒ St |  ƒ t | ƒ k rq d Sd } t rº xh t |  | ƒ D]& \ } } | t | ƒ t | ƒ AO} q� Wn. x+ t |  | ƒ D] \ } } | | | AO} qÊ W| d k S)zöThis 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
    zutf-8NFr   )Ú
isinstancer   r   Ú_builtin_safe_str_cmpÚlenr   r   Úord)ÚaÚbr   ÚxÚyr   r   r   Úsafe_str_cmpZ   s    !r,   c             C   s8   |  d k r t  d ƒ ‚ d j d d „  t |  ƒ Dƒ ƒ S)zAGenerate a random string of SALT_CHARS with specified ``length``.r   zSalt length must be positiveÚ c             s   s   |  ] } t  j t ƒ Vq d  S)N)Ú_sys_rngÚchoiceÚ
SALT_CHARS)r   Ú_r   r   r   r   |   s    zgen_salt.<locals>.<genexpr>)Ú
ValueErrorÚjoinr   )Úlengthr   r   r   Úgen_saltx   s    r5   c       	      C   sj  |  d k r | |  f St  | t ƒ r4 | j d ƒ } |  j d ƒ rÄ |  d d … j d ƒ } t | ƒ d k rz t d	 ƒ ‚ | j d
 ƒ }  | r¥ t | d
 pŸ d
 ƒ p¨ t	 } d } d |  | f } n d } |  } | r| sè t d ƒ ‚ t
 | | | d |  ƒ} n] | rHt  | t ƒ r'| j d ƒ } t | | |  ƒ } | j ƒ  } n t j |  | ƒ j ƒ  } | | f S)z�Internal password hash helper.  Supports plaintext without salt,
    unsalted and salted passwords.  In case salted passwords are used
    hmac is used.
    Úplainzutf-8zpbkdf2:é   Nú:r   é   z&Invalid number of arguments for PBKDF2r   Tzpbkdf2:%s:%dFzSalt is required for PBKDF2r   )r   r9   )r$   r   r   Ú
startswithÚsplitr&   r2   ÚpopÚintÚDEFAULT_PBKDF2_ITERATIONSr   Ú_create_macÚ	hexdigestr!   Únew)	Úmethodr   ÚpasswordÚargsr   Z	is_pbkdf2Úactual_methodr   Úmacr   r   r   Ú_hash_internal   s2    
"rG   c                sP   t  ˆ  ƒ r t j |  | ˆ  ƒ Sd ‡  f d d † } | | _ t j |  | | ƒ S)Nó    c                s   t  j ˆ  |  ƒ S)N)r!   rA   )Úd)rB   r   r   r   ¨   s    z_create_mac.<locals>.hashfunc)r   ÚhmacÚHMACÚ__call__)ÚkeyÚmsgrB   r   r   )rB   r   r?   ¤   s
    	r?   zpbkdf2:sha256é   c             C   sG   | d k r t  | ƒ n d } t | | |  ƒ \ } } d | | | f S)aø  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.
    r6   r-   z%s$%s$%s)r5   rG   )rC   rB   Zsalt_lengthr   ÚhrE   r   r   r   Úgenerate_password_hash±   s    rQ   c             C   sQ   |  j  d ƒ d k  r d S|  j d d ƒ \ } } } t t | | | ƒ d | ƒ S)aÉ  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.
    ú$r9   Fr   )Úcountr;   r,   rG   )ZpwhashrC   rB   r   Zhashvalr   r   r   Úcheck_password_hashÏ   s    rT   c                sŸ   |  g } x† | D]~ ‰  ˆ  d k r1 t  j ˆ  ƒ ‰  t ‡  f d d †  t Dƒ ƒ s} t j j ˆ  ƒ s} ˆ  d k s} ˆ  j d ƒ r� d S| j ˆ  ƒ q Wt  j	 | Œ  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   |  ] } | ˆ  k Vq d  S)Nr   )r   r   )Úfilenamer   r   r   ð   s    zsafe_join.<locals>.<genexpr>z..z../N)
Ú	posixpathÚnormpathÚanyÚ_os_alt_sepsÚosÚpathÚisabsr:   Úappendr3   )Ú	directoryZ	pathnamesÚpartsr   )rU   r   Ú	safe_joinà   s    		r`   )&Ú__doc__r   r!   rJ   rZ   rV   Úrandomr   Ústructr   Ú_compatr   r   r   r   r	   r
   r0   r>   ÚpackZ	_pack_intr    r%   r.   Úlistr[   r   ÚaltseprY   r   r   r,   r5   rG   r?   rQ   rT   r`   r   r   r   r   Ú<module>
   s:   	( %