#!/usr/bin/env python
# $Id: unix_ftpd.py 977 2012-01-22 23:05:09Z g.rodola $

#  pyftpdlib is released under the MIT license, reproduced below:
#  ======================================================================
#  Copyright (C) 2007-2012 Giampaolo Rodola' <g.rodola@gmail.com>
#
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# files (the "Software"), to deal in the Software without
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# copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following
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# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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#  ======================================================================

"""A FTPd using local UNIX account database to authenticate users.

It temporarily impersonate the system users every time they are going
to perform a filesystem operations.
"""

from pyftpdlib import ftpserver
from pyftpdlib.contrib.authorizers import UnixAuthorizer
from pyftpdlib.contrib.filesystems import UnixFilesystem


def main():
    authorizer = UnixAuthorizer(rejected_users=["root"], require_valid_shell=True)
    ftp_handler = ftpserver.FTPHandler
    ftp_handler.authorizer = authorizer
    ftp_handler.abstracted_fs = UnixFilesystem
    address = ('', 21)
    ftpd = ftpserver.FTPServer(address, ftp_handler)
    ftpd.serve_forever()

if __name__ == "__main__":
    main()