# This code is part of Ansible, but is an independent component.
# This particular file snippet, and this file snippet only, is BSD licensed.
# Modules you write using this snippet, which is embedded dynamically by Ansible
# still belong to the author of the module, and may assign their own license
# to the complete work.
#
# Copyright (c), Michael DeHaan <michael.dehaan@gmail.com>, 2012-2013
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without modification,
# are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
# USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type
from functools import cmp_to_key
from ansible.module_utils._text import to_text
from ansible.module_utils.six import binary_type
from ansible.module_utils.six import string_types
def _hashable_policy(policy, policy_list):
"""
Takes a policy and returns a list, the contents of which are all hashable and sorted.
Example input policy:
{'Version': '2012-10-17',
'Statement': [{'Action': 's3:PutObjectAcl',
'Sid': 'AddCannedAcl2',
'Resource': 'arn:aws:s3:::test_policy/*',
'Effect': 'Allow',
'Principal': {'AWS': ['arn:aws:iam::XXXXXXXXXXXX:user/username1', 'arn:aws:iam::XXXXXXXXXXXX:user/username2']}
}]}
Returned value:
[('Statement', ((('Action', ('s3:PutObjectAcl',)),
('Effect', ('Allow',)),
('Principal', ('AWS', (('arn:aws:iam::XXXXXXXXXXXX:user/username1',), ('arn:aws:iam::XXXXXXXXXXXX:user/username2',)))),
('Resource', ('arn:aws:s3:::test_policy/*',)), ('Sid', ('AddCannedAcl2',)))),
('Version', ('2012-10-17',)))]
"""
# Amazon will automatically convert bool and int to strings for us
if isinstance(policy, bool):
return tuple([str(policy).lower()])
elif isinstance(policy, int):
return tuple([str(policy)])
if isinstance(policy, list):
for each in policy:
tupleified = _hashable_policy(each, [])
if isinstance(tupleified, list):
tupleified = tuple(tupleified)
policy_list.append(tupleified)
elif isinstance(policy, string_types) or isinstance(policy, binary_type):
policy = to_text(policy)
# convert root account ARNs to just account IDs
if policy.startswith('arn:aws:iam::') and policy.endswith(':root'):
policy = policy.split(':')[4]
return [policy]
elif isinstance(policy, dict):
sorted_keys = list(policy.keys())
sorted_keys.sort()
for key in sorted_keys:
element = policy[key]
# Special case defined in
# https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_principal.html
if key in ["NotPrincipal", "Principal"] and policy[key] == "*":
element = {"AWS": "*"}
tupleified = _hashable_policy(element, [])
if isinstance(tupleified, list):
tupleified = tuple(tupleified)
policy_list.append((key, tupleified))
# ensure we aren't returning deeply nested structures of length 1
if len(policy_list) == 1 and isinstance(policy_list[0], tuple):
policy_list = policy_list[0]
if isinstance(policy_list, list):
policy_list.sort(key=cmp_to_key(_py3cmp))
return policy_list
def _py3cmp(a, b):
""" Python 2 can sort lists of mixed types. Strings < tuples. Without this function this fails on Python 3."""
try:
if a > b:
return 1
elif a < b:
return -1
else:
return 0
except TypeError as e:
# check to see if they're tuple-string
# always say strings are less than tuples (to maintain compatibility with python2)
str_ind = to_text(e).find('str')
tup_ind = to_text(e).find('tuple')
if -1 not in (str_ind, tup_ind):
if str_ind < tup_ind:
return -1
elif tup_ind < str_ind:
return 1
raise
def compare_policies(current_policy, new_policy, default_version="2008-10-17"):
""" Compares the existing policy and the updated policy
Returns True if there is a difference between policies.
"""
# https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_version.html
if default_version:
if isinstance(current_policy, dict):
current_policy = current_policy.copy()
current_policy.setdefault("Version", default_version)
if isinstance(new_policy, dict):
new_policy = new_policy.copy()
new_policy.setdefault("Version", default_version)
return set(_hashable_policy(new_policy, [])) != set(_hashable_policy(current_policy, []))
def sort_json_policy_dict(policy_dict):
""" Sort any lists in an IAM JSON policy so that comparison of two policies with identical values but
different orders will return true
Args:
policy_dict (dict): Dict representing IAM JSON policy.
Basic Usage:
>>> my_iam_policy = {'Principle': {'AWS':["31","7","14","101"]}
>>> sort_json_policy_dict(my_iam_policy)
Returns:
Dict: Will return a copy of the policy as a Dict but any List will be sorted
{
'Principle': {
'AWS': [ '7', '14', '31', '101' ]
}
}
"""
def value_is_list(my_list):
checked_list = []
for item in my_list:
if isinstance(item, dict):
checked_list.append(sort_json_policy_dict(item))
elif isinstance(item, list):
checked_list.append(value_is_list(item))
else:
checked_list.append(item)
# Sort list. If it's a list of dictionaries, sort by tuple of key-value
# pairs, since Python 3 doesn't allow comparisons such as `<` between dictionaries.
checked_list.sort(key=lambda x: sorted(x.items()) if isinstance(x, dict) else x)
return checked_list
ordered_policy_dict = {}
for key, value in policy_dict.items():
if isinstance(value, dict):
ordered_policy_dict[key] = sort_json_policy_dict(value)
elif isinstance(value, list):
ordered_policy_dict[key] = value_is_list(value)
else:
ordered_policy_dict[key] = value
return ordered_policy_dict