lemur/lemur/auth/views.py

580 lines
19 KiB
Python

"""
.. module: lemur.auth.views
:platform: Unix
:copyright: (c) 2018 by Netflix Inc., see AUTHORS for more
:license: Apache, see LICENSE for more details.
.. moduleauthor:: Kevin Glisson <kglisson@netflix.com>
"""
import jwt
import base64
import requests
from flask import Blueprint, current_app
from flask_restful import reqparse, Resource, Api
from flask_principal import Identity, identity_changed
from lemur.constants import SUCCESS_METRIC_STATUS, FAILURE_METRIC_STATUS
from lemur.extensions import metrics
from lemur.common.utils import get_psuedo_random_string
from lemur.users import service as user_service
from lemur.roles import service as role_service
from lemur.auth.service import create_token, fetch_token_header, get_rsa_public_key
from lemur.auth import ldap
mod = Blueprint("auth", __name__)
api = Api(mod)
def exchange_for_access_token(
code, redirect_uri, client_id, secret, access_token_url=None, verify_cert=True
):
"""
Exchanges authorization code for access token.
:param code:
:param redirect_uri:
:param client_id:
:param secret:
:param access_token_url:
:param verify_cert:
:return:
:return:
"""
# take the information we have received from the provider to create a new request
params = {
"grant_type": "authorization_code",
"scope": "openid email profile address",
"code": code,
"redirect_uri": redirect_uri,
"client_id": client_id,
}
# the secret and cliendId will be given to you when you signup for the provider
token = "{0}:{1}".format(client_id, secret)
basic = base64.b64encode(bytes(token, "utf-8"))
headers = {
"Content-Type": "application/x-www-form-urlencoded",
"authorization": "basic {0}".format(basic.decode("utf-8")),
}
# exchange authorization code for access token.
r = requests.post(
access_token_url, headers=headers, params=params, verify=verify_cert
)
if r.status_code == 400:
r = requests.post(
access_token_url, headers=headers, data=params, verify=verify_cert
)
id_token = r.json()["id_token"]
access_token = r.json()["access_token"]
return id_token, access_token
def validate_id_token(id_token, client_id, jwks_url):
"""
Ensures that the token we receive is valid.
:param id_token:
:param client_id:
:param jwks_url:
:return:
"""
# fetch token public key
header_data = fetch_token_header(id_token)
# retrieve the key material as specified by the token header
r = requests.get(jwks_url)
for key in r.json()["keys"]:
if key["kid"] == header_data["kid"]:
secret = get_rsa_public_key(key["n"], key["e"])
algo = header_data["alg"]
break
else:
return dict(message="Key not found"), 401
# validate your token based on the key it was signed with
try:
jwt.decode(
id_token, secret.decode("utf-8"), algorithms=[algo], audience=client_id
)
except jwt.DecodeError:
return dict(message="Token is invalid"), 401
except jwt.ExpiredSignatureError:
return dict(message="Token has expired"), 401
except jwt.InvalidTokenError:
return dict(message="Token is invalid"), 401
def retrieve_user(user_api_url, access_token):
"""
Fetch user information from provided user api_url.
:param user_api_url:
:param access_token:
:return:
"""
user_params = dict(access_token=access_token, schema="profile")
headers = {}
if current_app.config.get("PING_INCLUDE_BEARER_TOKEN"):
headers = {"Authorization": f"Bearer {access_token}"}
# retrieve information about the current user.
r = requests.get(user_api_url, params=user_params, headers=headers)
profile = r.json()
user = user_service.get_by_email(profile["email"])
return user, profile
def create_user_roles(profile):
"""Creates new roles based on profile information.
:param profile:
:return:
"""
roles = []
# update their google 'roles'
if "googleGroups" in profile:
for group in profile["googleGroups"]:
role = role_service.get_by_name(group)
if not role:
role = role_service.create(
group,
description="This is a google group based role created by Lemur",
third_party=True,
)
if not role.third_party:
role = role_service.set_third_party(role.id, third_party_status=True)
roles.append(role)
else:
current_app.logger.warning(
"'googleGroups' not sent by identity provider, no specific roles will assigned to the user."
)
role = role_service.get_by_name(profile["email"])
if not role:
role = role_service.create(
profile["email"],
description="This is a user specific role",
third_party=True,
)
if not role.third_party:
role = role_service.set_third_party(role.id, third_party_status=True)
roles.append(role)
# every user is an operator (tied to a default role)
if current_app.config.get("LEMUR_DEFAULT_ROLE"):
default = role_service.get_by_name(current_app.config["LEMUR_DEFAULT_ROLE"])
if not default:
default = role_service.create(
current_app.config["LEMUR_DEFAULT_ROLE"],
description="This is the default Lemur role.",
)
if not default.third_party:
role_service.set_third_party(default.id, third_party_status=True)
roles.append(default)
return roles
def update_user(user, profile, roles):
"""Updates user with current profile information and associated roles.
:param user:
:param profile:
:param roles:
"""
# if we get an sso user create them an account
if not user:
user = user_service.create(
profile["email"],
get_psuedo_random_string(),
profile["email"],
True,
profile.get("thumbnailPhotoUrl"),
roles,
)
else:
# we add 'lemur' specific roles, so they do not get marked as removed
for ur in user.roles:
if not ur.third_party:
roles.append(ur)
# update any changes to the user
user_service.update(
user.id,
profile["email"],
profile["email"],
True,
profile.get("thumbnailPhotoUrl"), # profile isn't google+ enabled
roles,
)
class Login(Resource):
"""
Provides an endpoint for Lemur's basic authentication. It takes a username and password
combination and returns a JWT token.
This token token is required for each API request and must be provided in the Authorization Header for the request.
::
Authorization:Bearer <token>
Tokens have a set expiration date. You can inspect the token expiration by base64 decoding the token and inspecting
it's contents.
.. note:: It is recommended that the token expiration is fairly short lived (hours not days). This will largely depend \
on your uses cases but. It is important to not that there is currently no build in method to revoke a users token \
and force re-authentication.
"""
def __init__(self):
self.reqparse = reqparse.RequestParser()
super(Login, self).__init__()
def post(self):
"""
.. http:post:: /auth/login
Login with username:password
**Example request**:
.. sourcecode:: http
POST /auth/login HTTP/1.1
Host: example.com
Accept: application/json, text/javascript
{
"username": "test",
"password": "test"
}
**Example response**:
.. sourcecode:: http
HTTP/1.1 200 OK
Vary: Accept
Content-Type: text/javascript
{
"token": "12343243243"
}
:arg username: username
:arg password: password
:statuscode 401: invalid credentials
:statuscode 200: no error
"""
self.reqparse.add_argument("username", type=str, required=True, location="json")
self.reqparse.add_argument("password", type=str, required=True, location="json")
args = self.reqparse.parse_args()
if "@" in args["username"]:
user = user_service.get_by_email(args["username"])
else:
user = user_service.get_by_username(args["username"])
# default to local authentication
if user and user.check_password(args["password"]) and user.active:
# Tell Flask-Principal the identity changed
identity_changed.send(
current_app._get_current_object(), identity=Identity(user.id)
)
metrics.send(
"login", "counter", 1, metric_tags={"status": SUCCESS_METRIC_STATUS}
)
return dict(token=create_token(user))
# try ldap login
if current_app.config.get("LDAP_AUTH"):
try:
ldap_principal = ldap.LdapPrincipal(args)
user = ldap_principal.authenticate()
if user and user.active:
# Tell Flask-Principal the identity changed
identity_changed.send(
current_app._get_current_object(), identity=Identity(user.id)
)
metrics.send(
"login",
"counter",
1,
metric_tags={"status": SUCCESS_METRIC_STATUS},
)
return dict(token=create_token(user))
except Exception as e:
current_app.logger.error("ldap error: {0}".format(e))
ldap_message = "ldap error: %s" % e
metrics.send(
"login", "counter", 1, metric_tags={"status": FAILURE_METRIC_STATUS}
)
return dict(message=ldap_message), 403
# if not valid user - no certificates for you
metrics.send(
"login", "counter", 1, metric_tags={"status": FAILURE_METRIC_STATUS}
)
return dict(message="The supplied credentials are invalid"), 403
class Ping(Resource):
"""
This class serves as an example of how one might implement an SSO provider for use with Lemur. In
this example we use an OpenIDConnect authentication flow, that is essentially OAuth2 underneath. If you have an
OAuth2 provider you want to use Lemur there would be two steps:
1. Define your own class that inherits from :class:`flask_restful.Resource` and create the HTTP methods the \
provider uses for its callbacks.
2. Add or change the Lemur AngularJS Configuration to point to your new provider
"""
def __init__(self):
self.reqparse = reqparse.RequestParser()
super(Ping, self).__init__()
def get(self):
return "Redirecting..."
def post(self):
self.reqparse.add_argument("clientId", type=str, required=True, location="json")
self.reqparse.add_argument(
"redirectUri", type=str, required=True, location="json"
)
self.reqparse.add_argument("code", type=str, required=True, location="json")
args = self.reqparse.parse_args()
# you can either discover these dynamically or simply configure them
access_token_url = current_app.config.get("PING_ACCESS_TOKEN_URL")
user_api_url = current_app.config.get("PING_USER_API_URL")
secret = current_app.config.get("PING_SECRET")
id_token, access_token = exchange_for_access_token(
args["code"],
args["redirectUri"],
args["clientId"],
secret,
access_token_url=access_token_url,
)
jwks_url = current_app.config.get("PING_JWKS_URL")
error_code = validate_id_token(id_token, args["clientId"], jwks_url)
if error_code:
return error_code
user, profile = retrieve_user(user_api_url, access_token)
roles = create_user_roles(profile)
update_user(user, profile, roles)
if not user or not user.active:
metrics.send(
"login", "counter", 1, metric_tags={"status": FAILURE_METRIC_STATUS}
)
return dict(message="The supplied credentials are invalid"), 403
# Tell Flask-Principal the identity changed
identity_changed.send(
current_app._get_current_object(), identity=Identity(user.id)
)
metrics.send(
"login", "counter", 1, metric_tags={"status": SUCCESS_METRIC_STATUS}
)
return dict(token=create_token(user))
class OAuth2(Resource):
def __init__(self):
self.reqparse = reqparse.RequestParser()
super(OAuth2, self).__init__()
def get(self):
return "Redirecting..."
def post(self):
self.reqparse.add_argument("clientId", type=str, required=True, location="json")
self.reqparse.add_argument(
"redirectUri", type=str, required=True, location="json"
)
self.reqparse.add_argument("code", type=str, required=True, location="json")
args = self.reqparse.parse_args()
# you can either discover these dynamically or simply configure them
access_token_url = current_app.config.get("OAUTH2_ACCESS_TOKEN_URL")
user_api_url = current_app.config.get("OAUTH2_USER_API_URL")
verify_cert = current_app.config.get("OAUTH2_VERIFY_CERT")
secret = current_app.config.get("OAUTH2_SECRET")
id_token, access_token = exchange_for_access_token(
args["code"],
args["redirectUri"],
args["clientId"],
secret,
access_token_url=access_token_url,
verify_cert=verify_cert,
)
jwks_url = current_app.config.get("PING_JWKS_URL")
error_code = validate_id_token(id_token, args["clientId"], jwks_url)
if error_code:
return error_code
user, profile = retrieve_user(user_api_url, access_token)
roles = create_user_roles(profile)
update_user(user, profile, roles)
if not user.active:
metrics.send(
"login", "counter", 1, metric_tags={"status": FAILURE_METRIC_STATUS}
)
return dict(message="The supplied credentials are invalid"), 403
# Tell Flask-Principal the identity changed
identity_changed.send(
current_app._get_current_object(), identity=Identity(user.id)
)
metrics.send(
"login", "counter", 1, metric_tags={"status": SUCCESS_METRIC_STATUS}
)
return dict(token=create_token(user))
class Google(Resource):
def __init__(self):
self.reqparse = reqparse.RequestParser()
super(Google, self).__init__()
def post(self):
access_token_url = "https://accounts.google.com/o/oauth2/token"
people_api_url = "https://www.googleapis.com/plus/v1/people/me/openIdConnect"
self.reqparse.add_argument("clientId", type=str, required=True, location="json")
self.reqparse.add_argument(
"redirectUri", type=str, required=True, location="json"
)
self.reqparse.add_argument("code", type=str, required=True, location="json")
args = self.reqparse.parse_args()
# Step 1. Exchange authorization code for access token
payload = {
"client_id": args["clientId"],
"grant_type": "authorization_code",
"redirect_uri": args["redirectUri"],
"code": args["code"],
"client_secret": current_app.config.get("GOOGLE_SECRET"),
}
r = requests.post(access_token_url, data=payload)
token = r.json()
# Step 2. Retrieve information about the current user
headers = {"Authorization": "Bearer {0}".format(token["access_token"])}
r = requests.get(people_api_url, headers=headers)
profile = r.json()
user = user_service.get_by_email(profile["email"])
if not (user and user.active):
metrics.send(
"login", "counter", 1, metric_tags={"status": FAILURE_METRIC_STATUS}
)
return dict(message="The supplied credentials are invalid."), 403
if user:
metrics.send(
"login", "counter", 1, metric_tags={"status": SUCCESS_METRIC_STATUS}
)
return dict(token=create_token(user))
metrics.send(
"login", "counter", 1, metric_tags={"status": FAILURE_METRIC_STATUS}
)
class Providers(Resource):
def get(self):
active_providers = []
for provider in current_app.config.get("ACTIVE_PROVIDERS", []):
provider = provider.lower()
if provider == "google":
active_providers.append(
{
"name": "google",
"clientId": current_app.config.get("GOOGLE_CLIENT_ID"),
"url": api.url_for(Google),
}
)
elif provider == "ping":
active_providers.append(
{
"name": current_app.config.get("PING_NAME"),
"url": current_app.config.get("PING_REDIRECT_URI"),
"redirectUri": current_app.config.get("PING_REDIRECT_URI"),
"clientId": current_app.config.get("PING_CLIENT_ID"),
"responseType": "code",
"scope": ["openid", "email", "profile", "address"],
"scopeDelimiter": " ",
"authorizationEndpoint": current_app.config.get(
"PING_AUTH_ENDPOINT"
),
"requiredUrlParams": ["scope"],
"type": "2.0",
}
)
elif provider == "oauth2":
active_providers.append(
{
"name": current_app.config.get("OAUTH2_NAME"),
"url": current_app.config.get("OAUTH2_REDIRECT_URI"),
"redirectUri": current_app.config.get("OAUTH2_REDIRECT_URI"),
"clientId": current_app.config.get("OAUTH2_CLIENT_ID"),
"responseType": "code",
"scope": ["openid", "email", "profile", "groups"],
"scopeDelimiter": " ",
"authorizationEndpoint": current_app.config.get(
"OAUTH2_AUTH_ENDPOINT"
),
"requiredUrlParams": ["scope", "state", "nonce"],
"state": "STATE",
"nonce": get_psuedo_random_string(),
"type": "2.0",
}
)
return active_providers
api.add_resource(Login, "/auth/login", endpoint="login")
api.add_resource(Ping, "/auth/ping", endpoint="ping")
api.add_resource(Google, "/auth/google", endpoint="google")
api.add_resource(OAuth2, "/auth/oauth2", endpoint="oauth2")
api.add_resource(Providers, "/auth/providers", endpoint="providers")