This is a fork of the Kong OIDC plugin by Nokia, which adds some extra functionality to help support ADFS. ADFS has some "quirks" that mean the original plugin does not work out of the box.
Problems discovered when trying to use Kong OIDC with ADFS:
- Custom claims are not passed through without specifying a non-OIDC-standard "resource" parameter to be the same as the relying party trust id. See
relying_party_trust_id - Timing of JWT tokens can be out by a fair amount, resulting in errors such as "token is not valid yet". Use the
slackparameter below to solve this issue. - In the OIDC flow, if the user fails authentication (wrong username and password), they are stopped at the credentials entry screen presented by ADFS. However, if the user authenticates but is not authorised to view the particular resource, which could happen if, for example, the user does not belong to the correct group, then ADFS still authenticates them and passes them back to Kong requesting an error page. This can result in continuous redirects between Kong and ADFS, and so needs to be handled by the plugin. See
auth_error_filter - ADFS does not implment the userinfo endpoint correctly. Instead, it passes custom claims through id_token. The userinfo endpoint appears hard-coded to only pass the "sub" claim. See
use_id_token_for_userinfo
| Parameter | Default | Required | description |
|---|---|---|---|
slack |
120 | false | the amount of discrepancy allowed between timestamps in JWT tokens |
relying_party_trust_id |
false | the relying party trust id. This MUST be specified if you wish to receive custom claims | |
use_id_token_for_userinfo |
false | false | should the plugin pass the claims in id_token in the X-Userinfo header |
auth_error_filter |
false | filters (regex) matched against the entire request URL that will force the plugin to report a 401 unauthorized |
If using luarocks (like you should), this plugin has been published to the luarocks repository, and can be installed using:
luarocks install kong-oidc-adfs
Original README.MD from the kong-oidc plugin included below for convenience.
Continuous Integration: 
kong-oidc is a plugin for Kong implementing the OpenID Connect Relying Party (RP) functionality.
It authenticates users against an OpenID Connect Provider using OpenID Connect Discovery and the Basic Client Profile (i.e. the Authorization Code flow).
It maintains sessions for authenticated users by leveraging lua-resty-openidc thus offering
a configurable choice between storing the session state in a client-side browser cookie or use
in of the server-side storage mechanisms shared-memory|memcache|redis.
It supports server-wide caching of resolved Discovery documents and validated Access Tokens.
It can be used as a reverse proxy terminating OAuth/OpenID Connect in front of an origin server so that the origin server/services can be protected with the relevant standards without implementing those on the server itself.
Introspection functionality add capability for already authenticated users and/or applications that already posses acces token to go through kong. The actual token verification is then done by Resource Server.
The diagram below shows the message exchange between the involved parties.
The X-Userinfo header contains the payload from the Userinfo Endpoint
X-Userinfo: {"preferred_username":"alice","id":"60f65308-3510-40ca-83f0-e9c0151cc680","sub":"60f65308-3510-40ca-83f0-e9c0151cc680"}
The plugin also sets the ngx.ctx.authenticated_consumer variable, which can be using in other Kong plugins:
ngx.ctx.authenticated_consumer = {
id = "60f65308-3510-40ca-83f0-e9c0151cc680", -- sub field from Userinfo
username = "alice" -- preferred_username from Userinfo
}
kong-oidc depends on the following package:
If you're using luarocks execute the following:
luarocks install kong-oidc
You also need to set the KONG_CUSTOM_PLUGINS environment variable
export KONG_CUSTOM_PLUGINS=oidc
| Parameter | Default | Required | description |
|---|---|---|---|
name |
true | plugin name, has to be oidc |
|
config.client_id |
true | OIDC Client ID | |
config.client_secret |
true | OIDC Client secret | |
config.discovery |
https://.well-known/openid-configuration | false | OIDC Discovery Endpoint (/.well-known/openid-configuration) |
config.scope |
oidc | false | OAuth2 Token scope. To use OIDC it has to contains the oidc scope |
config.ssl_verify |
false | false | Enable SSL verification to OIDC Provider |
config.session_secret |
false | Additional parameter, which is used to encrypt the session cookie. Needs to be random | |
config.introspection_endpoint |
false | Token introspection endpoint | |
config.bearer_only |
no | false | Only introspect tokens without redirecting |
config.realm |
kong | false | Realm used in WWW-Authenticate response header |
config.logout_path |
/logout | false | Absolute path used to logout from the OIDC RP |
config.http_proxy |
false | Http proxy url | |
config.https_proxy |
false | https proxy url (only supports url format http://proxy and not https://proxy) |
To enable the plugin only for one API:
POST /apis/<api_id>/plugins/ HTTP/1.1
Host: localhost:8001
Content-Type: application/x-www-form-urlencoded
Cache-Control: no-cache
name=oidc&config.client_id=kong-oidc&config.client_secret=29d98bf7-168c-4874-b8e9-9ba5e7382fa0&config.discovery=https%3A%2F%2F<oidc_provider>%2F.well-known%2Fopenid-configuration
To enable the plugin globally:
POST /apis HTTP/1.1
Host: localhost:8001
Content-Type: application/x-www-form-urlencoded
Cache-Control: no-cache
name=oidc&config.client_id=kong-oidc&config.client_secret=29d98bf7-168c-4874-b8e9-9ba5e7382fa0&config.discovery=https%3A%2F%2F<oidc_provider>%2F.well-known%2Fopenid-configuration
A successful response:
HTTP/1.1 201 Created
Date: Tue, 24 Oct 2017 19:37:38 GMT
Content-Type: application/json; charset=utf-8
Transfer-Encoding: chunked
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: kong/0.11.0
{
"created_at": 1508871239797,
"config": {
"response_type": "code",
"client_id": "kong-oidc",
"discovery": "https://<oidc_provider>/.well-known/openid-configuration",
"scope": "openid",
"ssl_verify": "no",
"client_secret": "29d98bf7-168c-4874-b8e9-9ba5e7382fa0",
"token_endpoint_auth_method": "client_secret_post"
},
"id": "58cc119b-e5d0-4908-8929-7d6ed73cb7de",
"enabled": true,
"name": "oidc",
"api_id": "32625081-c712-4c46-b16a-5d6d9081f85f"
}
The plugin adds a additional X-Userinfo header to the upstream request, which can be consumer by upstream server. It contains Userinfo base64 encoded:
GET / HTTP/1.1
Host: netcat:9000
Connection: keep-alive
X-Forwarded-For: 172.19.0.1
X-Forwarded-Proto: http
X-Forwarded-Host: localhost
X-Forwarded-Port: 8000
X-Real-IP: 172.19.0.1
Cache-Control: max-age=0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36
Upgrade-Insecure-Requests: 1
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
Accept-Encoding: gzip, deflate
Accept-Language: pl-PL,pl;q=0.8,en-US;q=0.6,en;q=0.4
Cookie: session=KOn1am4mhQLKazlCA.....
X-Userinfo: eyJnaXZlbl9uYW1lIjoixITEmMWaw5PFgcW7xbnEhiIsInN1YiI6ImM4NThiYzAxLTBiM2ItNDQzNy1hMGVlLWE1ZTY0ODkwMDE5ZCIsInByZWZlcnJlZF91c2VybmFtZSI6ImFkbWluIiwibmFtZSI6IsSExJjFmsOTxYHFu8W5xIYiLCJ1c2VybmFtZSI6ImFkbWluIiwiaWQiOiJjODU4YmMwMS0wYjNiLTQ0MzctYTBlZS1hNWU2NDg5MDAxOWQifQ==
To run the CI locally you can use the following command:
docker run --rm -it -v `pwd`:/app --workdir=/app python bash ci/run.sh