What is Kong OIDC plugin

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.

Note: at the moment, there is an issue using memcached/redis, probably due to session locking: the sessions freeze. Help to debug this is appreciated. I am currently using shared memory to store sessions.

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.

The introspection functionality adds capability for already authenticated users and/or applications that already possess access token to go through kong. The actual token verification is then done by Resource Server.

How does it work

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_credential variable, which can be using in other Kong plugins:

ngx.ctx.authenticated_credential = {
    id = "60f65308-3510-40ca-83f0-e9c0151cc680",   -- sub field from Userinfo
    username = "alice"                             -- preferred_username from Userinfo
}

For successfully authenticated request, possible (anonymous) consumer identity set by higher priority plugin is cleared as part of setting the credentials.

The plugin will try to retrieve the user's groups from a field in the token (default groups) and set kong.ctx.shared.authenticated_groups so that Kong authorization plugins can make decisions based on the user's group membership.

Dependencies

kong-oidc depends on the following package:

lua-resty-openidc

Installation

If you're using luarocks execute the following:

 luarocks install kong-oidc

[Kong >= 0.14] Since KONG_CUSTOM_PLUGINS has been removed, you also need to set the KONG_PLUGINS environment variable to include besides the bundled ones, oidc

 export KONG_PLUGINS=bundled,oidc

Usage

Parameters

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`	openid	false	OAuth2 Token scope. To use OIDC it has to contains the `openid` 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.timeout`		false	OIDC endpoint calls timeout
`config.introspection_endpoint_auth_method`	client_secret_basic	false	Token introspection authentication method. `resty-openidc` supports `client_secret_(basic\|post)`
`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.unauth_action`	auth	false	What action to take when unauthenticated - `auth` to redirect to the login page and attempt (re)authenticatation, - `deny` to stop with 401
`config.recovery_page_path`		false	Path of a recovery page to redirect the user when error occurs (except 401). To not show any error, you can use '/' to redirect immediately home. The error will be logged server side.
`config.ignore_auth_filters`		false	A comma-separated list of endpoints to bypass authentication for
`config.redirect_uri`		false	A relative or absolute URI the OP will redirect to after successful authentication
`config.userinfo_header_name`	`X-Userinfo`	false	The name of the HTTP header to use when passing the UserInfo to the upstream server
`config.id_token_header_name`	`X-ID-Token`	false	The name of the HTTP header to use when passing the ID Token to the upstream server
`config.access_token_header_name`	`X-Access-Token`	false	The name of the HTTP header to use when passing the Access Token to the upstream server
`config.access_token_as_bearer`	no	false	Whether or not the access token should be passed as a Bearer token
`config.disable_userinfo_header`	no	false	Disable passing the Userinfo to the upstream server
`config.disable_id_token_header`	no	false	Disable passing the ID Token to the upstream server
`config.disable_access_token_header`	no	false	Disable passing the Access Token to the upstream server
`config.groups_claim`	groups	false	Name of the claim in the token to get groups from
`config.skip_already_auth_requests`	no	false	Ignore requests where credentials have already been set by a higher priority plugin such as basic-auth
`config.bearer_jwt_auth_enable`	no	false	Authenticate based on JWT (ID) token provided in Authorization (Bearer) header. Checks iss, sub, aud, exp, iat (as in ID token). `config.discovery` must be defined to discover JWKS
`config.bearer_jwt_auth_allowed_auds`		false	List of JWT token `aud` values allowed when validating JWT token in Authorization header. If not provided, uses value from `config.client_id`
`config.bearer_jwt_auth_signing_algs`	[ 'RS256' ]	false	List of allowed signing algorithms for Authorization header JWT token validation. Must match to OIDC provider and `resty-openidc` supported algorithms
`config.header_names`		false	List of custom upstream HTTP headers to be added based on claims. Must have same number of elements as `config.header_claims`. Example: `[ 'x-oidc-email', 'x-oidc-email-verified' ]`
`config.header_claims`		false	List of claims to be used as source for custom upstream headers. Claims are sourced from Userinfo, ID Token, Bearer JWT, Introspection, depending on auth method. Use only claims containing simple string values. Example: `[ 'email', 'email_verified'`

Enabling kong-oidc

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 /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

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"
}

Upstream API request

For successfully authenticated request, the plugin will set upstream header X-Credential-Identifier to contain sub claim from user info, ID token or introspection result. Header X-Anonymous-Consumer is cleared.

The plugin adds a additional X-Userinfo, X-Access-Token and X-Id-Token headers to the upstream request, which can be consumer by upstream server. All of them are 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==
X-Access-Token: eyJhbGciOiJSUzI1NiIsInR5cCIgOiAiSldUIiwia2lkIiA6ICJGenFSY0N1Ry13dzlrQUJBVng1ZG9sT2ZwTFhBNWZiRGFlVDRiemtnSzZRIn0.eyJqdGkiOiIxYjhmYzlkMC1jMjlmLTQwY2ItYWM4OC1kNzMyY2FkODcxY2IiLCJleHAiOjE1NDg1MTA4MjksIm5iZiI6MCwiaWF0IjoxNTQ4NTEwNzY5LCJpc3MiOiJodHRwOi8vMTkyLjE2OC4wLjk6ODA4MC9hdXRoL3JlYWxtcy9tYXN0ZXIiLCJhdWQiOlsibWFzdGVyLXJlYWxtIiwiYWNjb3VudCJdLCJzdWIiOiJhNmE3OGQ5MS01NDk0LTRjZTMtOTU1NS04NzhhMTg1Y2E0YjkiLCJ0eXAiOiJCZWFyZXIiLCJhenAiOiJrb25nIiwibm9uY2UiOiJmNGRkNDU2YzBjZTY4ZmFmYWJmNGY4ZDA3YjQ0YWE4NiIsImF1dGhfdGltZSI6…IiwibWFuYWdlLWFjY291bnQtbGlua3MiLCJ2aWV3LXByb2ZpbGUiXX19LCJzY29wZSI6Im9wZW5pZCBwcm9maWxlIGVtYWlsIiwiZW1haWxfdmVyaWZpZWQiOmZhbHNlLCJwcmVmZXJyZWRfdXNlcm5hbWUiOiJhZG1pbiJ9.GWuguFjSEDGxw_vbD04UMKxtai15BE2lwBO0YkSzp-NKZ2SxAzl0nyhZxpP0VTzk712nQ8f_If5-mQBf_rqEVnOraDmX5NOXP0B8AoaS1jsdq4EomrhZGqlWmuaV71Cnqrw66iaouBR_6Q0s8bgc1FpCPyACM4VWs57CBdTrAZ2iv8dau5ODkbEvSgIgoLgBbUvjRKz1H0KyeBcXlVSgHJ_2zB9q2HvidBsQEIwTP8sWc6er-5AltLbV8ceBg5OaZ4xHoramMoz2xW-ttjIujS382QQn3iekNByb62O2cssTP3UYC747ehXReCrNZmDA6ecdnv8vOfIem3xNEnEmQw
X-Id-Token: eyJuYmYiOjAsImF6cCI6ImtvbmciLCJpYXQiOjE1NDg1MTA3NjksImlzcyI6Imh0dHA6XC9cLzE5Mi4xNjguMC45OjgwODBcL2F1dGhcL3JlYWxtc1wvbWFzdGVyIiwiYXVkIjoia29uZyIsIm5vbmNlIjoiZjRkZDQ1NmMwY2U2OGZhZmFiZjRmOGQwN2I0NGFhODYiLCJwcmVmZXJyZWRfdXNlcm5hbWUiOiJhZG1pbiIsImF1dGhfdGltZSI6MTU0ODUxMDY5NywiYWNyIjoiMSIsInNlc3Npb25fc3RhdGUiOiJiNDZmODU2Ny0zODA3LTQ0YmMtYmU1Mi1iMTNiNWQzODI5MTQiLCJleHAiOjE1NDg1MTA4MjksImVtYWlsX3ZlcmlmaWVkIjpmYWxzZSwianRpIjoiMjI1ZDRhNDItM2Y3ZC00Y2I2LTkxMmMtOGNkYzM0Y2JiNTk2Iiwic3ViIjoiYTZhNzhkOTEtNTQ5NC00Y2UzLTk1NTUtODc4YTE4NWNhNGI5IiwidHlwIjoiSUQifQ==

Standard OpenID Connect Scopes and Claims

The OpenID Connect Core 1.0 profile specifies the following standard scopes and claims:

Scope	Claim(s)
`openid`	`sub`. In an ID Token, `iss`, `aud`, `exp`, `iat` will also be provided.
`profile`	Typically claims like `name`, `family_name`, `given_name`, `middle_name`, `preferred_username`, `nickname`, `picture` and `updated_at`
`email`	`email` and `email_verified` (boolean) indicating if the email address has been verified by the user

Note that the openid scope is a mandatory designator scope.

Description of the standard claims

Claim	Type	Description
`iss`	URI	The Uniform Resource Identifier uniquely identifying the OpenID Connect Provider (OP)
`aud`	string / array	The intended audiences. For ID tokens, the identity token is one or more clients. For Access tokens, the audience is typically one or more Resource Servers
`nbf`	integer	Not before timestamp in Unix Epoch time*. May be omitted or set to 0 to indicate that the audience can disregard the claim
`exp`	integer	Expires timestamp in Unix Epoch time*
`name`	string	Preferred display name. Ex. `John Doe`
`family_name`	string	Last name. Ex. `Doe`
`given_name`	string	First name. Ex. `John`
`middle_name`	string	Middle name. Ex. `Donald`
`nickname`	string	Nick name. Ex. `Johnny`
`preferred_username`	string	Preferred user name. Ex. `johdoe`
`picture`	base64	A Base-64 encoded picture (typically PNG or JPEG) of the subject
`updated_at`	integer	A timestamp in Unix Epoch time*

* (Seconds since January 1st 1970).

Passing the Access token as a normal Bearer token

To pass the access token to the upstream server as a normal Bearer token, configure the plugin as follows:

Key	Value
`config.access_token_header_name`	`Authorization`
`config.access_token_header_as_bearer`	`yes`

Development

Running Unit Tests

To run unit tests, run the following command:

./bin/run-unit-tests.sh

This may take a while for the first run, as the docker image will need to be built, but subsequent runs will be quick.

Building the Integration Test Environment

To build the integration environment (Kong with the oidc plugin enabled, and Keycloak as the OIDC Provider), you will first need to find your computer's IP, and assign that to the environment variable IP. Finally, you will run the ./bin/build-env.sh command. Here's an example:

export IP=192.168.0.1
./bin/build-env.sh

To tear the environment down:

./bin/teardown-env.sh

jvanderneutstulen / kong-oidc Goto Github PK

kong-oidc's Introduction