Authentication & Authorization (A&A)
Ticket: https://hysds-core.atlassian.net/browse/HC-259
Background information required to understanding the thought process and planning behind integrating A&A to HySDS
OpenID Connect 1.0
OpenID Connect is:
… a simple identity layer on top of the OAuth 2.0 protocol. It allows Clients to verify the identity of the End-User based on the authentication performed by an Authorization Server, as well as to obtain basic profile information about the End-User in an interoperable and REST-like manner.
It creates a set of standards which allows for SSO in a secure manner
OpenID Connect can ensure that a user can sign into one application and be authorized to use all apps that are protected as well
OpenID Connect provides multiple types of “flows” to authorize users:
Implicit flow - a simplified OAuth flow previously recommended for native apps and JavaScript apps where the access token was returned immediately without an extra authorization code exchange step
hysds_ui
will use an implicit flow because it is a pure javascript (front-end) application
Authorization flow to redirect users to login to a identity provider (Google, Facebook, etc.)
returns an authorization code, which in turn will be used by the your app’s backend to fetch an
id_token
,access_token
andrefresh_token
to the client
there are more but Authorization flow and Implicit flow are the most common
The access_token
& refresh_token
will be used to grant access to clients
JWT tokens allow systems to encode a JSON object into the token itself, which can be decoded by the application to retrieve user information (email, username, roles, etc.)
JWT tokens are separated into 3 sections:
Header
- info on encode algorithmPayload
- user info (email, username, roles, etc.)Signature
- created by taking the encoded header, the encoded payload, a secret, the algorithm specified in the header, and signing itit will ensure if the token has been tampered with (and ultimately reject the token)
JWT tokens are the best options for the “micro-service” architecture (multiple REST APIs) of HySDS because:
one set of tokens (
access_token
,refresh_token
) can be re-used by multiple applicationstokens can be decoded and the payload can be read to ensure role-based access to REST API endpoints
According to OpenID Connect standards, user info can be retrieved in 2 ways:
online method, making a request to the provider’s UserInfo endpoint
curl https://[provider endpoint]/.../protocol/openid-connect/userinfo
reliable but can increase latency of having to make additional requests to retrieving user info every time your service is being called (not scalable in the long run)
decoding JWT token
the user info is encoded in the token and can be retrieved without having to make additional requests (more scalable)
requirements:
if using the
HS256
algorithm, tokens can be encoded and decoded with thesecret_key
not secure. if the
secret_key
gets leaked users can create their own JWT tokens and can potentially have “superuser” access to your system
if using the
RS256
algorithm (more secure):tokens will be encoded with a
private_key
tokens will be decoded with a
public_key
import json from authlib.jose import jwt public_key = """ -----BEGIN PUBLIC KEY----- MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAi2W0DkV... -----END PUBLIC KEY----- """ token = 'eyJhbGciOiJSUzI1NiIsInR5cCIgOiAiSldUIiwia2lkIiA6ICJ0czA0c...' claims = jwt.decode(token, public_key) claims.validate() # will raise error if token expired
Example of JWT token:
According to the OpenID Connect documentation when your access_token
expires you can use the refresh_token
to retrieve a new token (add client_secret
for if client type is confidential
)
ex (with Keycloak
):
curl -s -X POST \
-d client_id=<client_id> \
-d client_secret=<client_secret> \
-d grant_type=refresh_token \
-d refresh_token=<refresh_token> \
"http://localhost:8080/auth/realms/<realm>/protocol/openid-connect/token" | python -m json.tool
response:
{
"access_token": "eyJhbGciOiJSUzI1NiIsIn...",
"expires_in": 300,
"refresh_expires_in": 1800,
"refresh_token": "eyJhbGciOiJIUzI1NiIsInR5cCI...",
"token_type": "Bearer",
"not-before-policy": 0,
"session_state": "183ebafb-93ed-408f-a2ea-3708f518a694",
"scope": "profile"
}
There are multiple SSO providers that use OpenID Connect for A&A:
SSO Providers:
Keycloak
Originally the plan was to use Keycloak for A&A:
Pros:
Able to handle separate role level access with the use of JWT Tokens
Open-source (supported by RedHat)
LDAP
integrationsync/import users from
LDAP
group to internal database
Cons:
Requires a SQL database (MySQL, PostgreSQL, etc.)
Keycloak guide from Red Hat on how to set up realms, client apps and client roles
uses Java’s
springboot
framework in the rest API integration but can be followed
OCIO advised against using Keycloak
, instead suggesting AWS Cognito
[meeting] with OCIO where 4 other projects are also working on
Jupyter
notebooks front-end to PCMs. The topic was raise for FN and public access to be able to sign into ADE+PCM for on-demand use. As a heads up, OCIO is recommending to not useKeycloak
and instead use AWS Cognito with some additional ELB proxies
AWS Cognito
According to this StackOverflow post:
Cognito exposes an OpenID Connect Discovery endpoint as described at https://openid.net/specs/openid-connect-discovery-1_0.html#ProviderConfigurationRequest at the following location:
https://cognito-idp.{region}.amazonaws.com/{userPoolId}/.well-known/openid-configuration
Because Cognito can be exposed as an OpenID Connect provider, a lot of what we have researched on OpenID Connect (specifically Keycloak
) can be applied in Cognito as well
but will still need to do additional research on implementation
Cognito doesn’t have clear instructions how to sync your LDAP
directory so will need to do further research. Related links:
Role-based access control using Amazon Cognito and an external identity provider
https://docs.aws.amazon.com/cognito/latest/developerguide/what-is-amazon-cognito.html
https://docs.aws.amazon.com/cognito/latest/developerguide/cognito-user-identity-pools.html
https://docs.aws.amazon.com/cognito/latest/developerguide/getting-started-with-identity-pools.html
JWT Tokens
Because AWS Cognito supports OpenID Connect, they supply users with a id_token
, refresh_token
and a access_token
example of a access_token
payload:
Subject (sub
)
The sub
claim is a unique identifier (UUID) for the authenticated user. It is not the same as the user name, which may not be unique.
Amazon Cognito groups (cognito:groups
)
The cognito:groups
claim is a list of groups the user belongs to (can be treated the same as roles)
Authentication time (auth_time
)
The auth_time
claim contains the time when the authentication occurred. Its value is a JSON
number that represents the number of seconds from 1970-01-01T0:0:0Z
as measured in UTC format. On refreshes, it represents the time when the original authentication occurred, not the time when the token was issued.
Issuer (iss
)
The iss
claim has the following format: https://cognito-idp.{region}.amazonaws.com/{userPoolId}
In the case (otello
, mozart
+ grq2
REST APIs) where a user would need to directly get a set of tokens directly (with username
+ password
) we can leverage boto3
to obtain it (as demonstrated in this StackOverflow post):
ElasticSearch
Authenticating ElasticSearch directly would require a major update in the HySDS core (hysds_commons, hysds) to fetch an access_token
for every background process & celery
worker
An alternative is to authenticate at the proxy (apache
or nginx
) level:
This is a work in progress as a lot of research still needs to be done
only authenticate for ElasticSearch requests coming from outside the server (
hysds_ui
, etc)internal processes can hit ES directly without having to fetch an
access_token
beforehandNGINX OpenID Connect Implementation
uses
OpenResty
so it’ll require additional setup
current research documented in repo:https://github.com/DustinKLo/nginx-openid-demo