3
g5                 @   s*  d 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	m
Z
 ddlmZ ddlmZ ddlmZmZ dd	lmZ dd
lmZ ddlmZ ejdZdZdZdZdZdZdZdZ de  Z!ej"ej# Z$dZ%dd Z&dd Z'dd Z(dd Z)dd Z*d d! Z+d"d# Z,d$d% Z-d&d' Z.G d(d) d)eZ/dS )*z
Cross Site Request Forgery Middleware.

This module provides a middleware that implements protection
against request forgeries from other sites.
    N)urlparse)settings)DisallowedHostImproperlyConfigured)get_callable)patch_vary_headers)constant_time_compareget_random_string)MiddlewareMixin)is_same_domain)log_responsezdjango.security.csrfz%Referer checking failed - no Referer.z@Referer checking failed - %s does not match any trusted origins.zCSRF cookie not set.z CSRF token missing or incorrect.z/Referer checking failed - Referer is malformed.zCReferer checking failed - Referer is insecure while host is secure.       Z
_csrftokenc               C   s
   t tjS )z/Return the view to be used for CSRF rejections.)r   r   ZCSRF_FAILURE_VIEW r   r   T/var/www/tester-filtro-web/env/lib/python3.6/site-packages/django/middleware/csrf.py_get_failure_view$   s    r   c               C   s   t ttdS )N)allowed_chars)r	   CSRF_SECRET_LENGTHCSRF_ALLOWED_CHARSr   r   r   r   _get_new_csrf_string)   s    r   c                sP   t  }t t fdd| D  fdd|D }dj fdd|D }|| S )z
    Given a secret (assumed to be a string of CSRF_ALLOWED_CHARS), generate a
    token by adding a mask and applying it to the secret.
    c             3   s   | ]} j |V  qd S )N)index).0x)charsr   r   	<genexpr>4   s    z&_mask_cipher_secret.<locals>.<genexpr> c             3   s&   | ]\}} || t    V  qd S )N)len)r   r   y)r   r   r   r   5   s    )r   r   zipjoin)secretmaskpairscipherr   )r   r   _mask_cipher_secret-   s
    &r$   c                sZ   | dt  }| t d } t t fdd| D  fdd|D }dj fdd|D S )z
    Given a token (assumed to be a string of CSRF_ALLOWED_CHARS, of length
    CSRF_TOKEN_LENGTH, and that its first half is a mask), use it to decrypt
    the second half to produce the original secret.
    Nc             3   s   | ]} j |V  qd S )N)r   )r   r   )r   r   r   r   B   s    z'_unmask_cipher_token.<locals>.<genexpr>r   c             3   s   | ]\}} ||  V  qd S )Nr   )r   r   r   )r   r   r   r   C   s    )r   r   r   r   )tokenr!   r"   r   )r   r   _unmask_cipher_token9   s
    &r&   c               C   s
   t t S )N)r$   r   r   r   r   r   _get_new_csrf_tokenF   s    r'   c             C   s@   d| j kr t }t|| j d< nt| j d }d| j d< t|S )a  
    Return the CSRF token required for a POST form. The token is an
    alphanumeric value. A new token is created if one is not already set.

    A side effect of calling this function is to make the csrf_protect
    decorator and the CsrfViewMiddleware add a CSRF cookie and a 'Vary: Cookie'
    header to the outgoing response.  For this reason, you may need to use this
    function lazily, as is done by the csrf context processor.
    CSRF_COOKIETCSRF_COOKIE_USED)METAr   r$   r&   )requestZcsrf_secretr   r   r   	get_tokenJ   s    


r,   c             C   s   | j jdt d d| _dS )zi
    Change the CSRF token in use for a request - should be done on login
    for security purposes.
    T)r)   r(   N)r*   updater'   csrf_cookie_needs_reset)r+   r   r   r   rotate_token]   s    r/   c             C   s<   t jd| rt S t| tkr"| S t| tkr6t| S t S )Nz[^a-zA-Z0-9])researchr'   r   CSRF_TOKEN_LENGTHr   r$   )r%   r   r   r   _sanitize_tokeni   s    r3   c             C   s   t t| t|S )N)r   r&   )request_csrf_token
csrf_tokenr   r   r   _compare_masked_tokensz   s    r6   c               @   sH   e Zd ZdZdd Zdd Zdd Zdd	 Zd
d Zdd Z	dd Z
dS )CsrfViewMiddlewarez
    Require a present and correct csrfmiddlewaretoken for POST requests that
    have a CSRF cookie, and set an outgoing CSRF cookie.

    This middleware should be used in conjunction with the {% csrf_token %}
    template tag.
    c             C   s
   d|_ d S )NT)csrf_processing_done)selfr+   r   r   r   _accept   s    zCsrfViewMiddleware._acceptc             C   s(   t  ||d}td||j||td |S )N)reasonzForbidden (%s): %s)responser+   logger)r   r   pathr=   )r9   r+   r;   r<   r   r   r   _reject   s    zCsrfViewMiddleware._rejectc             C   sv   t jr2y|jjtS  tk
r.   tdY qrX n@y|jt j }W n t	k
rV   d S X t
|}||krnd|_|S d S )NzCSRF_USE_SESSIONS is enabled, but request.session is not set. SessionMiddleware must appear before CsrfViewMiddleware in MIDDLEWARE.T)r   CSRF_USE_SESSIONSsessiongetCSRF_SESSION_KEYAttributeErrorr   ZCOOKIESCSRF_COOKIE_NAMEKeyErrorr3   r.   )r9   r+   Zcookie_tokenr5   r   r   r   
_get_token   s    zCsrfViewMiddleware._get_tokenc          
   C   sj   t jr.|jjt|jd krf|jd |jt< n8|jt j|jd t jt j	t j
t jt jt jd t|d d S )Nr(   )Zmax_agedomainr>   securehttponlyZsamesiteCookie)rK   )r   r@   rA   rB   rC   r*   
set_cookierE   ZCSRF_COOKIE_AGECSRF_COOKIE_DOMAINZCSRF_COOKIE_PATHZCSRF_COOKIE_SECUREZCSRF_COOKIE_HTTPONLYZCSRF_COOKIE_SAMESITEr   )r9   r+   r<   r   r   r   
_set_token   s    
zCsrfViewMiddleware._set_tokenc             C   s    | j |}|d k	r||jd< d S )Nr(   )rG   r*   )r9   r+   r5   r   r   r   process_request   s    
z"CsrfViewMiddleware.process_requestc                s  t |ddrd S t |ddr d S |jdkrt |ddrB| j|S |j rP|jjd	  d krl| j|tS t  d
 j	 j
fkr| j|tS  j	dkr| j|tS tjrtjntj}|d k	r|j }|dkrd||f }n$y|j }W n tk
r    Y nX ttj}|d k	r |j| t fdd|D sPt j  }| j||S | j|}	|	d krp| j|tS d
}
|jdkry|jjdd
}
W n tk
r   Y nX |
d
kr|jjtjd
}
t|
}
t |
|	s| j|t!S | j|S )Nr8   FZcsrf_exemptGETHEADOPTIONSTRACEZ_dont_enforce_csrf_checksZHTTP_REFERERr   https44380z%s:%sc             3   s   | ]}t  j|V  qd S )N)r   netloc)r   host)refererr   r   r     s    z2CsrfViewMiddleware.process_view.<locals>.<genexpr>POSTZcsrfmiddlewaretoken)rP   rQ   rR   rS   )rU   rV   )"getattrmethodr:   Z	is_securer*   rB   r?   REASON_NO_REFERERr   schemerW   REASON_MALFORMED_REFERERREASON_INSECURE_REFERERr   r@   ZSESSION_COOKIE_DOMAINrM   Zget_portget_hostr   listZCSRF_TRUSTED_ORIGINSappendanyREASON_BAD_REFERERgeturlrG   REASON_NO_CSRF_COOKIErZ   OSErrorZCSRF_HEADER_NAMEr3   r6   REASON_BAD_TOKEN)r9   r+   callbackcallback_argscallback_kwargsZgood_refererZserver_portZ
good_hostsr;   r5   r4   r   )rY   r   process_view   s^    








zCsrfViewMiddleware.process_viewc             C   sD   t |ddst |ddr|S |jjdds.|S | j|| d|_|S )Nr.   Fcsrf_cookie_setr)   T)r[   r*   rB   rN   rn   )r9   r+   r<   r   r   r   process_response=  s    z#CsrfViewMiddleware.process_responseN)__name__
__module____qualname____doc__r:   r?   rG   rN   rO   rm   ro   r   r   r   r   r7      s   
pr7   )0rs   loggingr0   stringurllib.parser   Zdjango.confr   Zdjango.core.exceptionsr   r   Zdjango.urlsr   Zdjango.utils.cacher   Zdjango.utils.cryptor   r	   Zdjango.utils.deprecationr
   Zdjango.utils.httpr   Zdjango.utils.logr   	getLoggerr=   r]   re   rg   ri   r_   r`   r   r2   ascii_lettersdigitsr   rC   r   r   r$   r&   r'   r,   r/   r3   r6   r7   r   r   r   r   <module>   sB   
	