moto/tests/test_kms/test_kms_policy_enforcement.py
2022-12-16 20:47:38 -01:00

130 lines
4.7 KiB
Python

import boto3
import json
import pytest
from botocore.exceptions import ClientError
from unittest import mock
from moto import mock_kms
from moto.kms.exceptions import AccessDeniedException
from moto.kms.models import Key
from moto.kms.policy_validator import validate_policy
from cryptography.hazmat.primitives.asymmetric import rsa
@mock_kms
class TestKMSPolicyEnforcement:
def setup_method(self, *args) -> None: # pylint: disable=unused-argument
self.client = boto3.client("kms", "us-east-1")
# The key-value is irrelevant, so let's mock the expensive cryptographic key-generation
# Patching does not work in ServerMode, but at least decorator tests times are improved
with mock.patch.object(rsa, "generate_private_key", return_value=""):
new_key = self.client.create_key(Description="t", Origin="AWS_KMS")
self.key_id = new_key["KeyMetadata"]["KeyId"]
@pytest.mark.parametrize(
"actions",
[["kms:*"], ["kms:unknown", "kms:*"], ["kms:DescribeKey"], ["kms:Describe*"]],
)
def test_policy__deny_based_on_actions(self, actions):
policy = {
"Version": "2012-10-17",
"Id": "",
"Statement": [
{
"Sid": "test",
"Effect": "Deny",
"Principal": "*",
"Action": actions,
"Resource": "*",
}
],
}
self.client.put_key_policy(
Policy=json.dumps(policy), PolicyName="default", KeyId=self.key_id
)
with pytest.raises(ClientError) as exc:
self.client.describe_key(KeyId=self.key_id)
err = exc.value.response["Error"]
err["Code"].should.equal("AccessDeniedException")
@pytest.mark.parametrize("actions", [["kms:unknown"], ["kms:describestuff"]])
def test_policy__allow_based_on_actions(self, actions):
policy = {
"Version": "2012-10-17",
"Id": "",
"Statement": [
{
"Sid": "test",
"Effect": "Deny",
"Principal": "*",
"Action": actions,
"Resource": "*",
}
],
}
self.client.put_key_policy(
Policy=json.dumps(policy), PolicyName="default", KeyId=self.key_id
)
key = self.client.describe_key(KeyId=self.key_id)["KeyMetadata"]
key["Description"].should.equal("t")
class TestKMSPolicyValidator:
def test_input_can_be_none(self):
validate_policy(None, None)
def test_key_can_have_no_policy(self):
validate_policy(self.create_key(policy=None), None)
def test_key_can_have_unreadable_policy(self):
validate_policy(self.create_key(policy="some policy"), None)
@pytest.mark.parametrize(
"action", ["kms:*", "kms:DescribeKey", "unknown", "", None]
)
def test_describe_key_is_allowed_for_actions(self, action):
policy = {
"Statement": [{"Effect": "Allow", "Action": [action], "Resource": "*"}]
}
key = self.create_key(policy=json.dumps(policy))
validate_policy(key, "kms:DescribeKey")
@pytest.mark.parametrize(
"action", ["kms:DeleteKey", "awslambda:DescribeKey", "unknown", "", None]
)
def test_describe_key_is_allowed_if_other_actions_are_allowed(self, action):
policy = {
"Statement": [{"Effect": "denY", "Action": [action], "Resource": "*"}]
}
key = self.create_key(policy=json.dumps(policy))
validate_policy(key, "kms:DescribeKey")
@pytest.mark.parametrize("action", ["kms:*", "kms:Describe*", "kms:DescribeKey"])
def test_describe_key_is_denied_for_all_possible_action_variations(self, action):
policy = {
"Statement": [{"Effect": "denY", "Action": [action], "Resource": "*"}]
}
key = self.create_key(policy=json.dumps(policy))
with pytest.raises(AccessDeniedException):
validate_policy(key, "kms:DescribeKey")
@pytest.mark.parametrize("resource", ["arn", "kms:*"])
def test_describe_key_is_allowed_for_unsupported_resources(self, resource):
policy = {
"Statement": [{"Effect": "denY", "Action": ["kms:*"], "Resource": resource}]
}
key = self.create_key(policy=json.dumps(policy))
validate_policy(key, "kms:DescribeKey")
def create_key(self, policy):
with mock.patch.object(rsa, "generate_private_key", return_value=""):
return Key(
account_id=None,
region=None,
description=None,
key_spec=None,
key_usage=None,
policy=policy,
)