Update local.py

Use default Python PAM module instead of pasta-code
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PaliPalo 2021-07-13 17:03:54 +02:00 committed by GitHub
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@ -2,6 +2,7 @@
import os
import pwd
import sys
import pam
from flask_login import AnonymousUserMixin
from .interface import BUIhandler, BUIuser, BUIloader
@ -145,163 +146,6 @@ class LocalUser(BUIuser):
def get_id(self):
return self.id
# HERE IS THE PAM MODULE FROM https://atlee.ca/software/pam/
# (c) 2007 Chris AtLee <chris@atlee.ca>
# Licensed under the MIT license:
# http://www.opensource.org/licenses/mit-license.php
"""
PAM module for python
Provides an authenticate function that will allow the caller to authenticate
a user against the Pluggable Authentication Modules (PAM) on the system.
Implemented using ctypes, so no compilation is necessary.
"""
from ctypes import CDLL, POINTER, Structure, CFUNCTYPE, cast, pointer, sizeof # noqa
from ctypes import c_void_p, c_uint, c_char_p, c_char, c_int # noqa
from ctypes.util import find_library # noqa
def load_library(nickname, search_names=None):
"""Load a library based on the result of find_library(nickname),
or hardcoded names found in `search_names`."""
library = None
if search_names is None:
search_names = []
# We try to guess the library name using `find_library`.
# If we found a name, we add it a the first to be tried for loading.
guess_path = find_library(nickname)
if guess_path is not None:
search_names.insert(0, guess_path)
# Try to load each name, and stop when a name was successfuly loaded.
for name in search_names:
try:
library = CDLL(name)
except OSError:
library = None
if library is not None:
return library
if library is None:
raise AssertionError("Failed to load '%s' library." % (nickname))
def load_library_from_aix_archive(path, member_name="shr.o"):
"""
Extract the shared object from the archive and load it as a normal
library.
"""
import atexit
import tempfile
import arpy
def remove_file_at_exit(path):
# Reimport os as it might be removed at exit.
import os
os.remove(path)
archive = arpy.AIXBigArchive(path)
archive.read_all_headers()
member = archive.archived_files[member_name]
temp_file = None
try:
temp_fd, path = tempfile.mkstemp()
temp_file = os.fdopen(temp_fd, "wb")
atexit.register(remove_file_at_exit, path)
temp_file.write(member.read())
finally:
if temp_file:
temp_file.close()
return CDLL(path)
if sys.platform.startswith("aix"):
LIBPAM = load_library_from_aix_archive("/lib/libpam.a")
LIBC = load_library_from_aix_archive("/lib/libc.a")
else:
LIBPAM = load_library("pam", ["libpam.so", "libpam.so.0", "libpam.so.1"])
LIBC = load_library("c", ["libc.so", "libc.so.6", "libc.so.5"])
CALLOC = LIBC.calloc
CALLOC.restype = c_void_p
CALLOC.argtypes = [c_uint, c_uint]
STRDUP = LIBC.strdup
STRDUP.argstypes = [c_char_p]
STRDUP.restype = POINTER(c_char) # NOT c_char_p !!!!
# Various constants
PAM_PROMPT_ECHO_OFF = 1
PAM_PROMPT_ECHO_ON = 2
PAM_ERROR_MSG = 3
PAM_TEXT_INFO = 4
class PamHandle(Structure):
"""wrapper class for pam_handle_t"""
_fields_ = [("handle", c_void_p)]
def __init__(self):
Structure.__init__(self)
self.handle = 0
class PamMessage(Structure):
"""wrapper class for pam_message structure"""
_fields_ = [
("msg_style", c_int),
("msg", POINTER(c_char)),
]
def __repr__(self):
return "<PamMessage %i '%s'>" % (self.msg_style, self.msg)
class PamResponse(Structure):
"""wrapper class for pam_response structure"""
_fields_ = [
("resp", POINTER(c_char)),
("resp_retcode", c_int),
]
def __repr__(self):
return "<PamResponse %i '%s'>" % (self.resp_retcode, self.resp)
CONV_FUNC = CFUNCTYPE(
c_int, c_int, POINTER(POINTER(PamMessage)), POINTER(POINTER(PamResponse)), c_void_p
)
class PamConv(Structure):
"""wrapper class for pam_conv structure"""
_fields_ = [("conv", CONV_FUNC), ("appdata_ptr", c_void_p)]
PAM_START = LIBPAM.pam_start
PAM_START.restype = c_int
PAM_START.argtypes = [c_char_p, c_char_p, POINTER(PamConv), POINTER(PamHandle)]
PAM_END = LIBPAM.pam_end
PAM_END.restpe = c_int
PAM_END.argtypes = [PamHandle, c_int]
PAM_AUTHENTICATE = LIBPAM.pam_authenticate
PAM_AUTHENTICATE.restype = c_int
PAM_AUTHENTICATE.argtypes = [PamHandle, c_int]
def authenticate(username, password, service="login"):
"""Returns True if the given username and password authenticate for the
given service. Returns False otherwise
@ -313,30 +157,5 @@ def authenticate(username, password, service="login"):
``service``: the PAM service to authenticate against.
Defaults to 'login'"""
@CONV_FUNC
def my_conv(n_messages, messages, p_response, app_data):
"""Simple conversation function that responds to any
prompt where the echo is off with the supplied password"""
# Create an array of n_messages response objects
addr = CALLOC(n_messages, sizeof(PamResponse))
p_response[0] = cast(addr, POINTER(PamResponse))
for i in range(n_messages):
if messages[i].contents.msg_style == PAM_PROMPT_ECHO_OFF:
pw_copy = STRDUP(str(password))
p_response.contents[i].resp = cast(pw_copy, POINTER(c_char))
p_response.contents[i].resp_retcode = 0
return 0
handle = PamHandle()
conv = PamConv(my_conv, 0)
retval = PAM_START(service, username, pointer(conv), pointer(handle))
if retval != 0:
# TODO: This is not an authentication error, something
# has gone wrong starting up PAM
PAM_END(handle, retval)
return False
retval = PAM_AUTHENTICATE(handle, 0)
e = PAM_END(handle, retval)
return retval == 0 and e == 0
pam_api = pam.pam()
return pam_api.authenticate( username, password, service )