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 |
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:
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: {"preferred_username":"alice","id":"60f65308-3510-40ca-83f0-e9c0151cc680","sub":"60f65308-3510-40ca-83f0-e9c0151cc680"}