Role Based Access Control (RBAC) Filter

The RBAC filter is used to authorize actions by identified downstream clients. This is useful to explicitly manage callers to an application and protect it from unexpected or forbidden agents. The filter supports configuration with either a safe-list (ALLOW) or block-list (DENY) set of policies, or a matcher with different actions, based off properties of the connection (IPs, ports, SSL subject) as well as the incoming request’s HTTP headers. This filter also supports policy in both enforcement and shadow mode, shadow mode won’t effect real users, it is used to test that a new set of policies work before rolling out to production.

When a request is denied, the RESPONSE_CODE_DETAILS will include the name of the matched policy that caused the deny in the format of rbac_access_denied_matched_policy[policy_name] (policy_name will be none if no policy matched), this helps to distinguish the deny from Envoy RBAC filter and the upstream backend.

• This filter should be configured with the type URL type.googleapis.com/envoy.extensions.filters.http.rbac.v3.RBAC.

• v3 API reference

Per-Route Configuration

The RBAC filter configuration can be overridden or disabled on a per-route basis by providing a RBACPerRoute configuration on the virtual host, route, or weighted cluster.

Statistics

The RBAC filter outputs statistics in the http.<stat_prefix>.rbac. namespace. The stat prefix comes from the owning HTTP connection manager.

For the shadow rule statistics shadow_allowed and shadow_denied, the shadow_rules_stat_prefix can be used to add an extra prefix to output the statistics in the http.<stat_prefix>.rbac.<shadow_rules_stat_prefix>. namespace.

Name	Type	Description
allowed	Counter	Total requests that were allowed access
denied	Counter	Total requests that were denied access
shadow_allowed	Counter	Total requests that would be allowed access by the filter’s shadow rules
shadow_denied	Counter	Total requests that would be denied access by the filter’s shadow rules
logged	Counter	Total requests that should be logged
not_logged	Counter	Total requests that should not be logged

Dynamic Metadata

The RBAC filter emits the following dynamic metadata.

For the shadow rules dynamic metadata shadow_effective_policy_id and shadow_engine_result, the shadow_rules_stat_prefix can be used to add an extra prefix to the corresponding dynamic metadata key.

Name	Type	Description
shadow_effective_policy_id	string	The effective shadow policy ID matching the action (if any).
shadow_engine_result	string	The engine result for the shadow rules (i.e. either allowed or denied).
access_log_hint	boolean	Whether the request should be logged. This metadata is shared and set under the key namespace envoy.common (See Shared Dynamic Metadata).