rustfs/docs/operations/oidc-console-integration.md

OIDC Console integration

Use this when: connecting RustFS Console login to an OpenID Connect provider (Keycloak, Authing, or any standards-compliant IdP), or debugging an OIDC redirect, token, or policy-mapping failure. Source of truth: crates/config/src/constants/oidc.rs (provider keys and RUSTFS_IDENTITY_OPENID_*), crates/iam/src/oidc.rs (discovery, PKCE, token validation, per-provider env suffixes), rustfs/src/admin/handlers/oidc.rs (authorize/callback handlers), crates/config/src/constants/app.rs (ENV_RUSTFS_BROWSER_REDIRECT_URL), crates/utils/src/egress.rs (ENV_OUTBOUND_ALLOW_ORIGINS), crates/policy/src/policy/policy.rs (built-in policies).

The RustFS side is vendor-neutral and is described once; what RustFS requires from any provider is tabulated in oidc-provider-requirements.md. The Keycloak and Authing sections contain only IdP-side steps and vendor caveats. Examples use provider id default and public origin https://rustfs.example.com.

Integration model

RustFS requires a standards-compliant OpenID Connect provider: discovery at <issuer>/.well-known/openid-configuration, authorization and token endpoints, a JWKS, and an authorization-code flow that returns an id_token. RustFS never calls a vendor's authorization API; access is decided by RustFS IAM policies after claim mapping. Protocol requirements for IdP vendors are collected in oidc-provider-requirements.md.

Login flow:

1. The browser opens https://rustfs.example.com/rustfs/admin/v3/oidc/authorize/<provider_id>.
2. RustFS creates state, nonce, and a PKCE S256 challenge and redirects to the IdP.
3. The IdP redirects back to /rustfs/admin/v3/oidc/callback/<provider_id>?code=...&state=....
4. RustFS exchanges the code at the token endpoint, sending client_id and client_secret in the request body (client_secret_post) together with the PKCE verifier.
5. RustFS validates the ID token signature (JWKS), issuer, audience, expiry, and nonce.
6. RustFS maps claim values to policy names and issues one-hour STS credentials to the Console.

In-flight state and PKCE verifiers are node-local: the authorize and callback requests must reach the same RustFS node.

Configuration keys

Every provider key can be set as RUSTFS_IDENTITY_OPENID_<KEY> in the process environment or as identity_openid <key>=<value> through mc admin config set. Names are constants in crates/config/src/constants/oidc.rs.

Provider key	Environment variable	Purpose
enable	RUSTFS_IDENTITY_OPENID_ENABLE	on loads the provider.
config_url	RUSTFS_IDENTITY_OPENID_CONFIG_URL	Issuer URL used for discovery. A trailing /.well-known/openid-configuration is stripped; any other .well-known path is rejected.
issuer	RUSTFS_IDENTITY_OPENID_ISSUER	Expected iss when it differs from config_url (internal discovery URL, public token issuer).
client_id, client_secret	RUSTFS_IDENTITY_OPENID_CLIENT_ID, RUSTFS_IDENTITY_OPENID_CLIENT_SECRET	Confidential client credentials.
scopes	RUSTFS_IDENTITY_OPENID_SCOPES	Comma-separated; openid is required.
other_audiences	RUSTFS_IDENTITY_OPENID_OTHER_AUDIENCES	Additional accepted aud values.
redirect_uri	RUSTFS_IDENTITY_OPENID_REDIRECT_URI	Callback URL sent to the IdP; must equal the URL registered there.
redirect_uri_dynamic	RUSTFS_IDENTITY_OPENID_REDIRECT_URI_DYNAMIC	on derives the callback from request headers. Keep off behind proxies.
claim_name, claim_prefix	RUSTFS_IDENTITY_OPENID_CLAIM_NAME, RUSTFS_IDENTITY_OPENID_CLAIM_PREFIX	Policy claim name and a fixed string prepended to each value. claim_prefix is not a mapping table.
groups_claim, roles_claim	RUSTFS_IDENTITY_OPENID_GROUPS_CLAIM, RUSTFS_IDENTITY_OPENID_ROLES_CLAIM	Flat top-level array claims whose values are RustFS policy names.
email_claim, username_claim	RUSTFS_IDENTITY_OPENID_EMAIL_CLAIM, RUSTFS_IDENTITY_OPENID_USERNAME_CLAIM	Identity claims shown in the Console.
role_policy	RUSTFS_IDENTITY_OPENID_ROLE_POLICY	One fixed policy for every login from this provider. Connectivity testing only.
display_name	RUSTFS_IDENTITY_OPENID_DISPLAY_NAME	Login button label.
hide_from_ui	RUSTFS_IDENTITY_OPENID_HIDE_FROM_UI	Hides the provider from /oidc/providers.

Process-level settings (environment only, never suffixed per provider):

Variable	Purpose
RUSTFS_BROWSER_REDIRECT_URL	Public browser origin used for callback generation, Console success redirects, and logout fallback.
RUSTFS_OUTBOUND_ALLOW_ORIGINS	Exact scheme://host[:port] origins RustFS may contact for discovery, JWKS, and token requests when the IdP resolves to a private, loopback, or container-network address. See outbound-connection-policy.md.

Named providers: to use provider id <id>, suffix every provider env var with _<id> (for example RUSTFS_IDENTITY_OPENID_CLIENT_ID_keycloak) and register the callback /rustfs/admin/v3/oidc/callback/<id>. Suffix scanning is parse_single_provider in crates/iam/src/oidc.rs.

Restart RustFS after changing any of these settings.

Environment example

export RUSTFS_BROWSER_REDIRECT_URL="https://rustfs.example.com"

export RUSTFS_IDENTITY_OPENID_ENABLE=on
export RUSTFS_IDENTITY_OPENID_CONFIG_URL="<ISSUER>"
export RUSTFS_IDENTITY_OPENID_CLIENT_ID="<CLIENT_ID>"
export RUSTFS_IDENTITY_OPENID_CLIENT_SECRET="<CLIENT_SECRET>"
export RUSTFS_IDENTITY_OPENID_SCOPES="openid,profile,email"
export RUSTFS_IDENTITY_OPENID_REDIRECT_URI="https://rustfs.example.com/rustfs/admin/v3/oidc/callback/default"
export RUSTFS_IDENTITY_OPENID_REDIRECT_URI_DYNAMIC=off
export RUSTFS_IDENTITY_OPENID_DISPLAY_NAME="<IdP name>"
export RUSTFS_IDENTITY_OPENID_GROUPS_CLAIM="groups"
export RUSTFS_IDENTITY_OPENID_ROLES_CLAIM="roles"
export RUSTFS_IDENTITY_OPENID_EMAIL_CLAIM="email"
export RUSTFS_IDENTITY_OPENID_USERNAME_CLAIM="preferred_username"

The same keys through admin config:

mc admin config set rustfs identity_openid \
  enable=on config_url="<ISSUER>" client_id="<CLIENT_ID>" client_secret="<CLIENT_SECRET>" \
  scopes="openid,profile,email" \
  redirect_uri="https://rustfs.example.com/rustfs/admin/v3/oidc/callback/default" \
  redirect_uri_dynamic=off display_name="<IdP name>" \
  groups_claim="groups" roles_claim="roles" email_claim="email" username_claim="preferred_username"
mc admin service restart rustfs

RUSTFS_BROWSER_REDIRECT_URL is not an identity_openid key; it must still be set in the process environment.

Redirect URL priority

1. Provider redirect_uri, when set, is the callback URL sent to the IdP.
2. RUSTFS_BROWSER_REDIRECT_URL, when set, is the public origin for callback generation when no provider redirect_uri exists, and for Console success and logout fallback redirects.
3. Request headers (Host, X-Forwarded-Proto) are used only when redirect_uri_dynamic=on and no browser redirect URL is configured.

Behind a reverse proxy or load balancer, set RUSTFS_BROWSER_REDIRECT_URL and keep session affinity for the authorize and callback requests.

Policy mapping

Claim values are used verbatim as policy names (after claim_prefix, if any). Names must satisfy is_safe_claim_policy_name in crates/iam/src/sys.rs: ASCII letters, digits, _, -, :, . only, so a value containing / (for example Keycloak's full group path /consoleAdmin) never matches. Built-in policies:

Policy	Grants
consoleAdmin	Full Console, admin, KMS, and S3 access.
readwrite	S3 read/write.
readonly	S3 read-only.
writeonly	S3 write-only.
diagnostics	Diagnostic admin access.

For first-contact testing only, RUSTFS_IDENTITY_OPENID_ROLE_POLICY=consoleAdmin grants every login full access; remove it before production.

Validation

1. Discovery:

curl -fsS "<ISSUER>/.well-known/openid-configuration" | jq '{issuer, authorization_endpoint, token_endpoint, jwks_uri, code_challenge_methods_supported, token_endpoint_auth_methods_supported, scopes_supported}'

issuer must equal RUSTFS_IDENTITY_OPENID_ISSUER when set, otherwise the issuer derived from RUSTFS_IDENTITY_OPENID_CONFIG_URL; code_challenge_methods_supported must include S256; token_endpoint_auth_methods_supported must include client_secret_post; scopes_supported must include every configured scope.

2. Provider visibility: curl -fsS https://rustfs.example.com/rustfs/admin/v3/oidc/providers | jq lists the provider unless hide_from_ui=on.

3. Browser login: open https://rustfs.example.com/rustfs/admin/v3/oidc/authorize/default. Expect a redirect to the IdP, sign-in, a redirect to /rustfs/admin/v3/oidc/callback/default?code=...&state=..., and then the Console with the mapped permissions.

4. ID token claims (decode the token after a test login): iss matches the issuer, aud includes the client id, email and preferred_username are present when configured, groups or roles is a flat array of policy names.

Troubleshooting

Symptom	Common cause	Fix
/oidc/providers does not list the provider	provider failed to load, or RustFS was not restarted	Check env/admin config and restart RustFS.
Provider or login button missing; startup logs OIDC provider discovery blocked by outbound policy	IdP origin is private/internal and not allowlisted	Add the exact origin to RUSTFS_OUTBOUND_ALLOW_ORIGINS on every node and restart.
IdP reports a redirect mismatch (invalid redirect_uri)	registered callback differs from RustFS redirect_uri	Use the exact /rustfs/admin/v3/oidc/callback/<provider_id> URL on both sides.
Callback reports missing code or state	proxy dropped the query string	Preserve the full callback URL and query string.
Token exchange fails	wrong secret, or the IdP rejects request-body client authentication	Confirm the client is confidential and accepts client_secret_post.
No id_token in the token response	openid scope missing or a non-OIDC OAuth flow	Add openid; use the authorization-code flow.
ID token verification fails	issuer, audience, algorithm, or JWKS mismatch	Compare discovery metadata with CONFIG_URL/ISSUER/CLIENT_ID; prefer RS256.
Login succeeds, access denied	no claim value matches a policy name	Emit groups or roles as a flat array equal to policy names; check for / prefixes.
Console redirects to an internal host	RUSTFS_BROWSER_REDIRECT_URL unset or proxy headers wrong	Set RUSTFS_BROWSER_REDIRECT_URL to the public origin.
Invalid or expired OIDC state	callback reached a different node	Configure load-balancer session affinity for authorize and callback.

Production checklist

• RustFS and the IdP use HTTPS.
• The IdP registers the exact callback URL (no wildcard) and RUSTFS_IDENTITY_OPENID_REDIRECT_URI matches it.
• RUSTFS_BROWSER_REDIRECT_URL is the public browser origin.
• PKCE S256 is allowed or required at the IdP.
• ID tokens carry groups or roles values equal to RustFS policy names.
• role_policy is not used as a permanent shortcut.
• The load balancer preserves query strings and pins authorize/callback to one node.
• Internal IdP origins are listed exactly in RUSTFS_OUTBOUND_ALLOW_ORIGINS on every node.

Keycloak

Value	Example
Realm	rustfs
Issuer (config_url)	https://keycloak.example.com/realms/rustfs
Discovery URL	https://keycloak.example.com/realms/rustfs/.well-known/openid-configuration
Client id	rustfs-console
Scopes	openid,profile,email
Groups claim	groups (flat array)

Client setup in the Keycloak Admin Console:

1. Create or select the realm and confirm discovery returns issuer equal to https://keycloak.example.com/realms/rustfs.
2. Clients → create: Client type = OpenID Connect, Client ID = rustfs-console.
3. Enable Client authentication and Standard flow; disable Implicit flow, Direct access grants, and Service accounts roles.
4. Valid redirect URIs = https://rustfs.example.com/rustfs/admin/v3/oidc/callback/default; Web origins = https://rustfs.example.com.
5. Proof Key for Code Exchange Code Challenge Method = S256.
6. Save and copy the secret from Credentials. Do not apply a client policy that disables client_secret_post.

Group mapper (a Group Membership mapper in the client's dedicated scope):

Mapper field	Value
Name	rustfs-groups
Token Claim Name	groups
Full group path	Off (a leading / breaks policy matching)
Add to ID token / access token / userinfo	On
Multivalued	On

Create Keycloak groups named after RustFS policies (consoleAdmin, readonly, ...) and add users to them.

Roles instead of groups: assign realm or client roles named after policies, add a User Realm Role or User Client Role mapper that emits a flat top-level roles claim, and set RUSTFS_IDENTITY_OPENID_ROLES_CLAIM=roles. RustFS does not read Keycloak's nested realm_access.roles claim.

Internal discovery URL with a public issuer (for example in-cluster Keycloak on Kubernetes):

export RUSTFS_IDENTITY_OPENID_CONFIG_URL="http://keycloak.keycloak.svc.cluster.local:8080/realms/rustfs"
export RUSTFS_IDENTITY_OPENID_ISSUER="https://keycloak.example.com/realms/rustfs"
export RUSTFS_OUTBOUND_ALLOW_ORIGINS="http://keycloak.keycloak.svc.cluster.local:8080"

Discovery and issuer-relative JWKS requests use the CONFIG_URL base; iss validation uses ISSUER. The allowlist entry is the origin only (no realm or discovery path) and is read at startup on every node. Prefer HTTPS with a trusted CA for the internal URL: discovery and JWKS define the token-signing trust root, so plain HTTP is acceptable only where DNS and traffic cannot be tampered with.

Authing

Value	Example	Note
Application domain	https://example.authing.cn	From the Authing application page.
Issuer (config_url)	https://example.authing.cn/oidc	Tenants differ (/oidc, /oauth/oidc): copy the issuer from the console and confirm discovery returns the same issuer.
App ID / App Secret	<AUTHING_APP_ID> / <AUTHING_APP_SECRET>	RustFS client_id / client_secret.
Scopes	openid,profile,email,roles	roles is needed when Authing emits role claims.
Roles claim	roles	Set RUSTFS_IDENTITY_OPENID_ROLES_CLAIM=roles.

Application settings in the Authing console:

Setting	Value
Protocol	OpenID Connect
Grant type / response type	Authorization Code / code
Token endpoint authentication	client_secret_post
PKCE	allow or require S256
ID token signing algorithm	RS256
Redirect URL	https://rustfs.example.com/rustfs/admin/v3/oidc/callback/default (exact)

Assign Authing roles whose names equal RustFS policy names; a test user with role consoleAdmin should produce "roles": ["consoleAdmin"] in the ID token. claim_prefix only prepends a fixed string, so keep role values equal to policy names unless policies with that prefix already exist.