A Wasm-plugin for the Envoy-Proxy written in Rust acting as an HTTP Filter, that implements the OpenID Authorization Code Flow. Requests sent to the filter are checked for the presence of a valid session cookie. If the cookie is not present, the user is redirected to the authorization_endpoint to authenticate. After successful authentication, the user is redirected back to the original path with the authorization code in the URL query. The plugin then exchanges the code for a token using the token_endpoint and stores the token in the session. If the cookie is present and decryptable, the plugin validates the token and passes the request to the backend, if the token is valid (optional).
Go to demo-page to see the plugin in action. Auth0 is used as the OpenID provider. Simply create an account or login with Google. The plugin has been configured to show httpbin.org as the upstream. Then open the developer tools and check the cookies or use the httpbin cookie inspector. You will see a cookie called oidcSession-0. This is the session, that holds the authorization state. If you delete the cookie and refresh the page, you will be redirected to the authorization_endpoint to authenticate again.
This repo is the result of a bachelor thesis in Information Systems. It is inspired by two other projects: oidc-filter & wasm-oauth-filter. This project has several advantages and improvements:
- Encryption: The session in which the authorization state is stored is encrypted using AES-256, by providing a Key in the config and a session-based nonce. This prevents the session from being read by the user and potentially modified. If the user tries to modify the session, the decryption fails and the user is redirected to the
authorization_endpointto authenticate again. - Multiple OpenID Providers: The plugin can be configured with multiple OpenID providers. This is useful if you have multiple services that are protected by different OpenID providers. The user can then choose which provider to authenticate with on some auth page.
- Configuration: Many configuration options are available to customize the plugin to your needs. More are coming ;)
- Stability: The plugin aims to be stable and ready for production. All forceful value unwraps are expected to be valid. If the value may be invalid or in the wrong format, error handling is in place.
- Optional validation: The plugin can be configured to validate the token or not. If the validation is disabled, the plugin only checks for the presence of the token and passes the request to the backend. This is because the validation is taking a considerable amount of time. This time becomes worse with the length of the signing key. Cryptographic support is not fully mature in WASM yet, but there is hope.
- Documentation and comments: The code is documented and commented, so that it is easy to understand and extend.
For developing the Rust Toolchain has to be installed and the WASM target has to be enabled. E.g. for Ubuntu this can be achieved by:
# Install Build essentials
apt install build-essential
# Install Rustup
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
# Enable WASM compilation target
cargo build --target wasm32-wasip1 --releaseShortcut (make sure to have make installed):
make run- Building the plugin:
cargo build --target wasm32-wasip1 --release
# or
make build- Testing locally with Envoy (docker and docker-compose are needed):
docker compose up- Requests to the locally running envoy with the plugin enabled:
curl localhost:10000To deploy the plugin to production, the following steps are needed (either manually or via a CI/CD pipeline):
-
Build the plugin
1.1 with
cargo build --target wasm32-wasip1 --release- this can be done in a initContainer (see k8s folder) and then copy the binary to the path/etc/envoy/proxy-wasm-plugins/in the envoy container.1.2 by using the pre-built Docker image antonengelhardt/wasm-oidc-plugin.
-
Run envoy as a container with the
envoy.yamlfile mounted through the ConfigMap as a volume. -
Set up Service, Certificate, Ingress to expose the Envoy to the internet.
For reference, see the k8s folder.
To generate a detailed documentation, run (also hosted on GitHub Pages):
cargo doc --document-private-items --openThe plugin is configured via the envoy.yaml-file. The following configuration options are required:
| Name | Type | Description | Example | Required |
|---|---|---|---|---|
exclude_hosts |
Vec<Regex> |
A comma separated list Hosts (in Regex expressions), that are excluded from the filter. | ["localhost:10000"] |
❌ |
exclude_paths |
Vec<Regex> |
A comma separated list of paths (in Regex expressions), that are excluded from the filter. | ["/health"] |
❌ |
exclude_urls |
Vec<Regex> |
A comma separated list of URLs (in Regex expressions), that are excluded from the filter. | ["http://localhost:10000/health"] |
❌ |
access_token_header_name |
string |
If set, this name will be used to forward the access token to the backend. | X-Access-Token |
❌ |
access_token_header_prefix |
string |
The prefix of the header, that is used to forward the access token, if empty "" is used. | Bearer |
❌ |
id_token_header_name |
string |
If set, this name will be used to forward the id token to the backend. | X-Id-Token |
❌ |
id_token_header_prefix |
string |
The prefix of the header, that is used to forward the id token, if empty "" is used. | Bearer |
❌ |
cookie_name |
string |
The name of the cookie, that is used to store the session. Will be suffixed with a dash and a number for multiple cookies if the state is too long. | oidcSession |
✅ |
logout_path |
string |
The path, that is used to logout the user. The user will be redirected to end_session_endpoint of the OIDC provider, if the server supports this; alternatively the user is sent to "/" |
/logout |
✅ |
filter_plugin_cookies |
bool |
Whether to filter the cookies that are managed and controlled by the plugin (namely cookie_name and nonce). |
true |
✅ |
cookie_duration_in_s |
u64 |
The duration in seconds, after which the session cookie expires. | 86400 |
✅ |
token_validation |
bool | Whether to validate the token or not. | true |
✅ |
aes_key |
string |
A base64 encoded AES-256 Key: openssl rand -base64 32 |
<generated-aes-key> |
✅ |
reload_interval_in_h |
u64 |
The interval in hours, after which the OpenID configuration is reloaded. | 24 |
✅ |
ticking_interval_in_ms |
u64 |
The interval in milliseconds, after which the plugin will wait for the discovery endpoint to respond or send a new request. | 500 |
✅ |
open_id_configs |
Vec<OpenIdConfig> |
A list of OpenID Configuration objects. | See below | ✅ |
| Name | Type | Description | Example | Required |
|---|---|---|---|---|
name |
string |
The name of the OpenID provider (this will be shown on the Auth Page). | Google |
✅ |
image |
string |
The URL to the image of the OpenID provider (this will be shown on the Auth Page). | https://upload.wikimedia.org/wikipedia/commons/thumb/2/2f/Google_2015_logo.svg/2560px-Google_2015_logo.svg.png |
✅ |
config_endpoint |
string |
The open id configuration endpoint. | https://accounts.google.com/.well-known/openid-configuration |
✅ |
upstream_cluster |
string |
The name of the upstream cluster in your Envoy configuration. | httpbin |
✅ |
authority |
string |
The authority of the authorization_endpoint. |
accounts.google.com |
✅ |
redirect_uri |
string |
The redirect URI, that the authorization_endpoint will redirect to. |
http://localhost:10000/oidc/callback |
✅ |
client_id |
string |
The client ID, for getting and exchanging the code. | wasm-oidc-plugin |
✅ |
scope |
string |
The scope, to validate | openid email |
✅ |
claims |
map |
The claims to request as defined here | See below | ✅ |
client_secret |
string |
The client secret, that is used to authenticate with the authorization_endpoint. |
secret |
✅ |
audience |
string |
The audience, that is used to validate the token. | wasm-oidc-plugin |
✅ |
The claims are defined as a map of strings.
claims:
id_token:
groups: null
username: nullLegacy configs (provider fields at the root) still work and are converted at runtime with a deprecation warning. Prefer migrating to open_id_configs.
Set upstream_cluster to an Envoy cluster name that actually exists — auto-derivation from authority is often wrong.
# Requires PyYAML. Accepts a bare plugin config or a full Envoy/ConfigMap YAML.
python3 scripts/migrate-config.py envoy-legacy.yaml -o envoy-migrated.yamlA state determines what to load next. The following states are possible and depending on the outcome, the state is changed or not:
| State | Description |
|---|---|
LoadingConfig |
The plugin is loading the configuration from all config_endpoints. |
LoadingJwks |
The plugin is loading the public keys from all jwks_uri. |
Ready |
The plugin is ready to handle requests and will reload the configuration after the reload_interval_in_h has passed. |
Below is a state diagram for one single OpenID Provider
stateDiagram-v2
[*] --> LoadingConfig: on_configure() creates resolvers
note right of LoadingConfig
Plugin config loaded + getting OpenIDConfig
end note
LoadingConfig --> LoadingJwks: OpenID config response received
note right of LoadingJwks
Getting Keys from Endpoint
end note
LoadingJwks --> Ready: JWKS response received
note right of Ready
Keys stored, providers created, queued requests resumed
end note
Ready --> LoadingConfig: [every reload_interval_in_h]
Ready --> Ready: Process HTTP requests
When a new request arrives, the root context creates a new http context with the information that has been loaded previously.
Then, one of the following cases is handled:
- The plugin is not configured yet and still loading the configuration. The request is paused and queued until the configuration is loaded. Then, the RootContext resumes the request and the Request is redirected in order to create a new context.
- The request is excluded from the filter. The request is passed to the backend without any further checks.
- The request has the authorization code in the URL query. This means that the user has been redirected back from the
authorization_endpointafter successful authentication. The plugin exchanges the code for a token using thetoken_endpointand stores the token in the session. Then, the user is redirected back to the original request. - The request has a valid session cookie. The plugin decoded, decrypts and then validates the cookie and passes the request depending on the outcome of the validation of the token.
- The request has no valid session cookie. The plugin redirects the user to the
authorization_endpointto authenticate. Once, the user returns, the second case is handled. If multiple OpenID providers are configured, the user is redirected to a page where they can select the provider to authenticate with.
sequenceDiagram
participant User
participant Plugin
participant Auth as Auth-Endpoint
participant Token as Token-Endpoint
participant App as App/Backend
Note over User, App: [No Cookies Present]
User->>Plugin: Tries to Access App/Backend
Plugin-->>User: Redirect to Auth-Endpoint
User->>Auth: User authenticates
Auth-->>Plugin: Authorization Code
Plugin->>Token: Exchange Code for Tokens
Token-->>Plugin: Tokens
Plugin-->>User: Reply with Cookies and redirect to Original Path
Note over User, App: [Cookies Present]
User->>Plugin: Tries to Access App/Backend
critical [Validation]
Plugin->>Plugin: Validate Cookie with keys
end
alt [Valid]
Plugin->>App: Allow Request
else [Invalid]
Plugin-->>User: Redirect to Auth-Endpoint
end
Git-Cliff automates the generation of changelogs, when following conventional commit messages
We are using Gitleaks to protect from unwanted secret leaking and prevent security incidents by detecting passwords, secrets, API keys, tokens and more in git repos.
To run gitleaks, install it first and then run:
gitleaks protect
# To get the list of leaks
gitleaks protect --verboseIf you want to install a pre-commit hook - you should - install pre-commit and run (from the root of the project):
pre-commit installThe pre-commit hook will also check for a clean code style, formatting best practices and enforce clippy lints.
Cargo-deny checks all dependencies for security vulnerabilities and license issues.
Install cargo-deny:
cargo install --locked cargo-denyAnd then run:
cargo-deny check licenses
cargo-deny check advisoriesThese commands are also run in the CI pipeline.
My OpenID provider uses different hosts for discovery, JWKS, and token exchange (e.g. Google). How can I configure this?
Google publishes:
{
"authorization_endpoint": "https://accounts.google.com/o/oauth2/v2/auth",
"token_endpoint": "https://oauth2.googleapis.com/token",
"jwks_uri": "https://www.googleapis.com/oauth2/v3/certs"
}Add all three hosts to the Envoy cluster and enable auto_sni so TLS SNI matches the :authority used for each call:
- name: google
connect_timeout: 5s
type: STRICT_DNS
dns_lookup_family: V4_ONLY
typed_extension_protocol_options:
envoy.extensions.upstreams.http.v3.HttpProtocolOptions:
"@type": type.googleapis.com/envoy.extensions.upstreams.http.v3.HttpProtocolOptions
explicit_http_config:
http_protocol_options: {}
upstream_http_protocol_options:
auto_sni: true
load_assignment:
cluster_name: google
endpoints:
- lb_endpoints:
- endpoint:
address:
socket_address:
address: accounts.google.com
port_value: 443
- endpoint:
address:
socket_address:
address: www.googleapis.com
port_value: 443
- endpoint:
address:
socket_address:
address: oauth2.googleapis.com
port_value: 443
transport_socket:
name: envoy.transport_sockets.tls
typed_config:
"@type": type.googleapis.com/envoy.extensions.transport_sockets.tls.v3.UpstreamTlsContextKeep authority as accounts.google.com for discovery; the plugin uses the token/JWKS URL host for those calls.
Also ensure the Google OAuth client has your redirect_uri (e.g. http://localhost:10000/oidc/callback) allowlisted.