Implemented finding credentials from already created IAM users and roles.

This commit is contained in:
acsbendi 2019-07-08 19:57:14 +02:00
parent 4ccf48e46b
commit 23957fe940
5 changed files with 206 additions and 59 deletions

View File

@ -6,19 +6,115 @@ from enum import Enum
from botocore.auth import SigV4Auth, S3SigV4Auth
from botocore.awsrequest import AWSRequest
from botocore.credentials import Credentials
from moto.iam.models import ACCOUNT_ID, Policy
from moto.iam import iam_backend
from moto.core.exceptions import SignatureDoesNotMatchError, AccessDeniedError, InvalidClientTokenIdError, InvalidAccessKeyIdError, AuthFailureError
from moto.s3.exceptions import BucketAccessDeniedError, S3AccessDeniedError, BucketInvalidTokenError, S3InvalidTokenError, S3InvalidAccessKeyIdError, BucketInvalidAccessKeyIdError
from moto.sts import sts_backend
from moto.core.exceptions import SignatureDoesNotMatchError, AccessDeniedError, InvalidClientTokenIdError
from moto.s3.exceptions import BucketAccessDeniedError, S3AccessDeniedError
ACCESS_KEY_STORE = {
"AKIAJDULPKHCC4KGTYVA": {
"owner": "avatao-user",
"secret_access_key": "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"
}
}
def create_access_key(access_key_id, headers):
if access_key_id.startswith("AKIA") or "X-Amz-Security-Token" not in headers:
return IAMUserAccessKey(access_key_id, headers)
else:
return AssumedRoleAccessKey(access_key_id, headers)
class IAMUserAccessKey:
def __init__(self, access_key_id, headers):
iam_users = iam_backend.list_users('/', None, None)
for iam_user in iam_users:
for access_key in iam_user.access_keys:
if access_key.access_key_id == access_key_id:
self._owner_user_name = iam_user.name
self._access_key_id = access_key_id
self._secret_access_key = access_key.secret_access_key
if "X-Amz-Security-Token" in headers:
raise CreateAccessKeyFailure(reason="InvalidToken")
return
raise CreateAccessKeyFailure(reason="InvalidId")
@property
def arn(self):
return "arn:aws:iam::{account_id}:user/{iam_user_name}".format(
account_id=ACCOUNT_ID,
iam_user_name=self._owner_user_name
)
def create_credentials(self):
return Credentials(self._access_key_id, self._secret_access_key)
def collect_policies(self):
user_policies = []
inline_policy_names = iam_backend.list_user_policies(self._owner_user_name)
for inline_policy_name in inline_policy_names:
inline_policy = iam_backend.get_user_policy(self._owner_user_name, inline_policy_name)
user_policies.append(inline_policy)
attached_policies, _ = iam_backend.list_attached_user_policies(self._owner_user_name)
user_policies += attached_policies
user_groups = iam_backend.get_groups_for_user(self._owner_user_name)
for user_group in user_groups:
inline_group_policy_names = iam_backend.list_group_policies(user_group)
for inline_group_policy_name in inline_group_policy_names:
inline_user_group_policy = iam_backend.get_group_policy(user_group.name, inline_group_policy_name)
user_policies.append(inline_user_group_policy)
attached_group_policies = iam_backend.list_attached_group_policies(user_group.name)
user_policies += attached_group_policies
return user_policies
class AssumedRoleAccessKey:
def __init__(self, access_key_id, headers):
for assumed_role in sts_backend.assumed_roles:
if assumed_role.access_key_id == access_key_id:
self._access_key_id = access_key_id
self._secret_access_key = assumed_role.secret_access_key
self._session_token = assumed_role.session_token
self._owner_role_name = assumed_role.arn.split("/")[-1]
self._session_name = assumed_role.session_name
if headers["X-Amz-Security-Token"] != self._session_name:
raise CreateAccessKeyFailure(reason="InvalidToken")
return
raise CreateAccessKeyFailure(reason="InvalidId")
@property
def arn(self):
return "arn:aws:sts::{account_id}:assumed-role/{role_name}/{session_name}".format(
account_id=ACCOUNT_ID,
role_name=self._owner_role_name,
session_name=self._session_name
)
def create_credentials(self):
return Credentials(self._access_key_id, self._secret_access_key, self._session_token)
def collect_policies(self):
role_policies = []
inline_policy_names = iam_backend.list_role_policies(self._owner_role_name)
for inline_policy_name in inline_policy_names:
inline_policy = iam_backend.get_role_policy(self._owner_role_name, inline_policy_name)
role_policies.append(inline_policy)
attached_policies, _ = iam_backend.list_attached_role_policies(self._owner_role_name)
role_policies += attached_policies
return role_policies
class CreateAccessKeyFailure(Exception):
def __init__(self, reason, *args):
super().__init__(*args)
self.reason = reason
class IAMRequestBase(ABC):
@ -31,10 +127,13 @@ class IAMRequestBase(ABC):
self._headers = headers
credential_scope = self._get_string_between('Credential=', ',', self._headers['Authorization'])
credential_data = credential_scope.split('/')
self._access_key = credential_data[0]
self._region = credential_data[2]
self._service = credential_data[3]
self._action = self._service + ":" + self._data["Action"][0]
try:
self._access_key = create_access_key(access_key_id=credential_data[0], headers=headers)
except CreateAccessKeyFailure as e:
self._raise_invalid_access_key(e.reason)
def check_signature(self):
original_signature = self._get_string_between('Signature=', ',', self._headers['Authorization'])
@ -43,48 +142,30 @@ class IAMRequestBase(ABC):
raise SignatureDoesNotMatchError()
def check_action_permitted(self):
iam_user_name = ACCESS_KEY_STORE[self._access_key]["owner"]
user_policies = self._collect_policies_for_iam_user(iam_user_name)
self._check_action_permitted_for_iam_user()
def _check_action_permitted_for_iam_user(self):
policies = self._access_key.collect_policies()
permitted = False
for policy in user_policies:
for policy in policies:
iam_policy = IAMPolicy(policy)
permission_result = iam_policy.is_action_permitted(self._action)
if permission_result == PermissionResult.DENIED:
self._raise_access_denied(iam_user_name)
self._raise_access_denied()
elif permission_result == PermissionResult.PERMITTED:
permitted = True
if not permitted:
self._raise_access_denied(iam_user_name)
self._raise_access_denied()
@abstractmethod
def _raise_access_denied(self, iam_user_name):
def _raise_access_denied(self):
raise NotImplementedError()
@staticmethod
def _collect_policies_for_iam_user(iam_user_name):
user_policies = []
inline_policy_names = iam_backend.list_user_policies(iam_user_name)
for inline_policy_name in inline_policy_names:
inline_policy = iam_backend.get_user_policy(iam_user_name, inline_policy_name)
user_policies.append(inline_policy)
attached_policies, _ = iam_backend.list_attached_user_policies(iam_user_name)
user_policies += attached_policies
user_groups = iam_backend.get_groups_for_user(iam_user_name)
for user_group in user_groups:
inline_group_policy_names = iam_backend.list_group_policies(user_group)
for inline_group_policy_name in inline_group_policy_names:
inline_user_group_policy = iam_backend.get_group_policy(user_group.name, inline_group_policy_name)
user_policies.append(inline_user_group_policy)
attached_group_policies = iam_backend.list_attached_group_policies(user_group.name)
user_policies += attached_group_policies
return user_policies
@abstractmethod
def _raise_invalid_access_key(self, reason):
raise NotImplementedError()
@abstractmethod
def _create_auth(self, credentials):
@ -107,11 +188,7 @@ class IAMRequestBase(ABC):
return request
def _calculate_signature(self):
if self._access_key not in ACCESS_KEY_STORE:
raise InvalidClientTokenIdError()
secret_key = ACCESS_KEY_STORE[self._access_key]["secret_access_key"]
credentials = Credentials(self._access_key, secret_key)
credentials = self._access_key.create_credentials()
auth = self._create_auth(credentials)
request = self._create_aws_request()
canonical_request = auth.canonical_request(request)
@ -125,23 +202,41 @@ class IAMRequestBase(ABC):
class IAMRequest(IAMRequestBase):
def _raise_invalid_access_key(self, _):
if self._service == "ec2":
raise AuthFailureError()
else:
raise InvalidClientTokenIdError()
def _create_auth(self, credentials):
return SigV4Auth(credentials, self._service, self._region)
def _raise_access_denied(self, iam_user_name):
def _raise_access_denied(self):
raise AccessDeniedError(
account_id=ACCOUNT_ID,
iam_user_name=iam_user_name,
user_arn=self._access_key.arn,
action=self._action
)
class S3IAMRequest(IAMRequestBase):
def _raise_invalid_access_key(self, reason):
if reason == "InvalidToken":
if "BucketName" in self._data:
raise BucketInvalidTokenError(bucket=self._data["BucketName"])
else:
raise S3InvalidTokenError()
else:
if "BucketName" in self._data:
raise BucketInvalidAccessKeyIdError(bucket=self._data["BucketName"])
else:
raise S3InvalidAccessKeyIdError()
def _create_auth(self, credentials):
return S3SigV4Auth(credentials, self._service, self._region)
def _raise_access_denied(self, _):
def _raise_access_denied(self):
if "BucketName" in self._data:
raise BucketAccessDeniedError(bucket=self._data["BucketName"])
else:

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@ -88,11 +88,29 @@ class InvalidClientTokenIdError(RESTError):
class AccessDeniedError(RESTError):
code = 403
def __init__(self, account_id, iam_user_name, action):
def __init__(self, user_arn, action):
super(AccessDeniedError, self).__init__(
'AccessDenied',
"User: arn:aws:iam::{account_id}:user/{iam_user_name} is not authorized to perform: {operation}".format(
account_id=account_id,
iam_user_name=iam_user_name,
"User: {user_arn} is not authorized to perform: {operation}".format(
user_arn=user_arn,
operation=action
))
class InvalidAccessKeyIdError(RESTError):
code = 400
def __init__(self):
super(InvalidAccessKeyIdError, self).__init__(
'InvalidAccessKeyId',
"The AWS Access Key Id you provided does not exist in our records.")
class AuthFailureError(RESTError):
code = 400
def __init__(self):
super(AuthFailureError, self).__init__(
'AuthFailure',
"AWS was not able to validate the provided access credentials")

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@ -111,21 +111,19 @@ class ActionAuthenticatorMixin(object):
INITIAL_NO_AUTH_ACTION_COUNT = int(os.environ.get("INITIAL_NO_AUTH_ACTION_COUNT", 999999999))
request_count = 0
def _authenticate_action(self, iam_request):
iam_request.check_signature()
def _authenticate_action(self, iam_request_cls):
if ActionAuthenticatorMixin.request_count >= ActionAuthenticatorMixin.INITIAL_NO_AUTH_ACTION_COUNT:
iam_request = iam_request_cls(method=self.method, path=self.path, data=self.data, headers=self.headers)
iam_request.check_signature()
iam_request.check_action_permitted()
else:
ActionAuthenticatorMixin.request_count += 1
def _authenticate_normal_action(self):
iam_request = IAMRequest(method=self.method, path=self.path, data=self.data, headers=self.headers)
self._authenticate_action(iam_request)
self._authenticate_action(IAMRequest)
def _authenticate_s3_action(self):
iam_request = S3IAMRequest(method=self.method, path=self.path, data=self.data, headers=self.headers)
self._authenticate_action(iam_request)
self._authenticate_action(S3IAMRequest)
class BaseResponse(_TemplateEnvironmentMixin, ActionAuthenticatorMixin):

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@ -213,3 +213,35 @@ class BucketAccessDeniedError(BucketError):
def __init__(self, *args, **kwargs):
super(BucketAccessDeniedError, self).__init__('AccessDenied', 'Access Denied', *args, **kwargs)
class S3InvalidTokenError(S3ClientError):
code = 400
def __init__(self, *args, **kwargs):
super(S3InvalidTokenError, self).__init__('InvalidToken', 'The provided token is malformed or otherwise invalid.', *args, **kwargs)
class BucketInvalidTokenError(BucketError):
code = 400
def __init__(self, *args, **kwargs):
super(BucketInvalidTokenError, self).__init__('InvalidToken', 'The provided token is malformed or otherwise invalid.', *args, **kwargs)
class S3InvalidAccessKeyIdError(S3ClientError):
code = 400
def __init__(self, *args, **kwargs):
super(S3InvalidAccessKeyIdError, self).__init__(
'InvalidAccessKeyId',
"The AWS Access Key Id you provided does not exist in our records.", *args, **kwargs)
class BucketInvalidAccessKeyIdError(S3ClientError):
code = 400
def __init__(self, *args, **kwargs):
super(BucketInvalidAccessKeyIdError, self).__init__(
'InvalidAccessKeyId',
"The AWS Access Key Id you provided does not exist in our records.", *args, **kwargs)

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@ -38,6 +38,9 @@ class AssumedRole(BaseModel):
class STSBackend(BaseBackend):
def __init__(self):
self.assumed_roles = []
def get_session_token(self, duration):
token = Token(duration=duration)
return token
@ -48,6 +51,7 @@ class STSBackend(BaseBackend):
def assume_role(self, **kwargs):
role = AssumedRole(**kwargs)
self.assumed_roles.append(role)
return role