Synnefo

# Copyright 2011-2012 GRNET S.A. All rights reserved.

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# without modification, are permitted provided that the following

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#      disclaimer.

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#      provided with the distribution.

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# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

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from django.conf import settings

from django.core.exceptions import MiddlewareNotUsed

from django.core import mail

HIDDEN_ALL = settings.HIDDEN_COOKIES + settings.HIDDEN_HEADERS

def mail_admins_safe(subject, message, fail_silently=False,

                     connection=None, html_message=None):

    '''

    Wrapper function to cleanse email body from sensitive content before

    sending it

    '''

    new_msg = ""

    if len(message) > settings.MAIL_MAX_LEN:

        new_msg += "Mail size over limit (truncated)\n\n"

        message = message[:settings.MAIL_MAX_LEN]

    for line in message.splitlines():

        # Lines of interest in the mail are in the form of

        # key:value.

        try:

            (key, value) = line.split(':', 1)

        except ValueError:

            new_msg += line + '\n'

            continue

        new_msg += key + ':'

        # Special case when the first header / cookie printed

        # (prefixed by 'META:{' or 'COOKIES:{') needs to be hidden.

        if value.startswith('{'):

            try:

                (newkey, newval) = value.split(':', 1)

            except ValueError:

                new_msg += value + '\n'

                continue

            new_msg += newkey + ':'

            key = newkey.lstrip('{')

            value = newval

        if key.strip(" '") not in HIDDEN_ALL:

            new_msg += value + '\n'

            continue

        # Append value[-1] to the clensed string, so that commas / closing

        # brackets are printed correctly.

        # (it will 'eat up' the closing bracket if the header is the last one

        # printed)

        new_msg += ' ' + '*'*8 + value[-1] + '\n'

    return mail.mail_admins_plain(subject, new_msg, fail_silently, connection)

class CleanseSettingsMiddleware(object):

    '''

    Prevent django from printing sensitive information (paswords, tokens

    etc), when handling server errors (for both DEBUG and no-DEBUG

    deployments.

    '''

    def __init__(self):

        if not hasattr(mail, 'mail_admins_plain'):

            mail.mail_admins_plain = mail.mail_admins

            mail.mail_admins = mail_admins_safe

        raise MiddlewareNotUsed('cleanse settings')