policy: Cleanup policy response labels (#6722)

Policy controller API responses include a set of labels. These labels
are to be used in proxy m$etrics to indicate why traffic is permitted to
a pod. This permits metrics to be associated with `Server` and
ServerAuthorization` resources (i.e. for `stat`).

This change updates the response API to include a `name` label
referencing the server's name. When the policy is derived from a default
configuration (and not a `Server` instance), the name takes the form
'default:<policy>'.

This change also updates authorization labels. Defaults are encoded as
servers are, otherwise the authorization's name is set as a label. The
`tls` and `authn` labels have been removed, as they're redundant with
other labels that are already present.

policy-controller/core/src/lib.rs

@@ -23,6 +23,7 @@ pub type InboundServerStream = Pin<Box<dyn Stream<Item = InboundServer> + Send +
 /// Inbound server configuration.
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct InboundServer {
+    pub name: String,
     pub protocol: ProxyProtocol,
     pub authorizations: HashMap<String, ClientAuthorization>,
 }

policy-controller/grpc/src/lib.rs

@@ -10,7 +10,7 @@ use linkerd_policy_controller_core::{
     ClientAuthentication, ClientAuthorization, DiscoverInboundServer, IdentityMatch, InboundServer,
     InboundServerStream, IpNet, NetworkMatch, ProxyProtocol,
 };
-use std::{collections::HashMap, sync::Arc};
+use std::sync::Arc;
 use tracing::trace;
 
 #[derive(Clone, Debug)]
@@ -20,12 +20,6 @@ pub struct Server<T> {
     cluster_networks: Arc<[IpNet]>,
 }
 
-struct Labels {
-    authn: bool,
-    tls: bool,
-    name: String,
-}
-
 // === impl Server ===
 
 impl<T> Server<T>
@@ -200,9 +194,15 @@ fn to_server(srv: &InboundServer, cluster_networks: &[IpNet]) -> proto::Server {
         .collect();
     trace!(?authorizations);
 
+    let labels = vec![("name".to_string(), srv.name.to_string())]
+        .into_iter()
+        .collect();
+    trace!(?labels);
+
     proto::Server {
         protocol: Some(protocol),
         authorizations,
+        labels,
         ..Default::default()
     }
 }
@@ -233,59 +233,32 @@ fn to_authz(
             .collect()
     };
 
-    match authentication {
+    let labels = vec![("name".to_string(), name.to_string())]
-        ClientAuthentication::Unauthenticated => {
+        .into_iter()
-            let labels = Labels {
+        .collect();
-                authn: false,
+
-                tls: false,
+    let authn = match authentication {
-                name: name.to_string(),
+        ClientAuthentication::Unauthenticated => proto::Authn {
-            };
-            proto::Authz {
-                networks,
-                labels: labels.into(),
-                authentication: Some(proto::Authn {
             permit: Some(proto::authn::Permit::Unauthenticated(
                 proto::authn::PermitUnauthenticated {},
             )),
-                }),
+        },
-            }
-        }
 
-        ClientAuthentication::TlsUnauthenticated => {
+        ClientAuthentication::TlsUnauthenticated => proto::Authn {
-            let labels = Labels {
-                authn: false,
-                tls: true,
-                name: name.to_string(),
-            };
-            proto::Authz {
-                networks,
-                labels: labels.into(),
-                authentication: Some(proto::Authn {
             permit: Some(proto::authn::Permit::MeshTls(proto::authn::PermitMeshTls {
                 clients: Some(proto::authn::permit_mesh_tls::Clients::Unauthenticated(
                     proto::authn::PermitUnauthenticated {},
                 )),
             })),
-                }),
+        },
-            }
-        }
 
         // Authenticated connections must have TLS and apply to all
         // networks.
         ClientAuthentication::TlsAuthenticated(identities) => {
-            let labels = Labels {
-                authn: true,
-                tls: true,
-                name: name.to_string(),
-            };
-
-            let authn = {
             let suffixes = identities
                 .iter()
                 .filter_map(|i| match i {
-                        IdentityMatch::Suffix(s) => {
+                    IdentityMatch::Suffix(s) => Some(proto::IdentitySuffix { parts: s.to_vec() }),
-                            Some(proto::IdentitySuffix { parts: s.to_vec() })
-                        }
                     _ => None,
                 })
                 .collect();
@@ -310,27 +283,12 @@ fn to_authz(
                     )),
                 })),
             }
+        }
     };
 
     proto::Authz {
         networks,
-                labels: labels.into(),
+        labels,
         authentication: Some(authn),
     }
 }
-    }
-}
-
-// === impl Labels ===
-
-impl From<Labels> for HashMap<String, String> {
-    fn from(labels: Labels) -> HashMap<String, String> {
-        vec![
-            ("authn".to_string(), labels.authn.to_string()),
-            ("tls".to_string(), labels.tls.to_string()),
-            ("name".to_string(), labels.name),
-        ]
-        .into_iter()
-        .collect()
-    }
-}

policy-controller/k8s/index/src/defaults.rs

@@ -171,6 +171,7 @@ impl DefaultPolicyWatches {
             }
 
             DefaultPolicy::Deny => InboundServer {
+                name: "default:deny".to_string(),
                 protocol,
                 authorizations: Default::default(),
             },
@@ -218,6 +219,7 @@ impl DefaultPolicyWatches {
         };
 
         InboundServer {
+            name: name.clone(),
             protocol,
             authorizations: Some((name, authz)).into_iter().collect(),
         }

policy-controller/k8s/index/src/server.rs

@@ -191,6 +191,7 @@ impl SrvIndex {
                     .collect::<HashMap<_, _>>();
                 debug!(authzs = ?authzs.keys());
                 let (tx, rx) = watch::channel(InboundServer {
+                    name: entry.key().clone(),
                     protocol: protocol.clone(),
                     authorizations: authzs.clone(),
                 });

policy-controller/k8s/index/src/tests.rs

@@ -40,15 +40,13 @@ async fn incrementally_configure_server() {
     );
     idx.apply_pod(pod.clone()).unwrap();
 
-    let default_config = InboundServer {
+    let default = DefaultPolicy::Allow {
-        authorizations: mk_default_policy(
-            DefaultPolicy::Allow {
         authenticated_only: false,
         cluster_only: true,
-            },
+    };
-            cluster_net,
+    let default_config = InboundServer {
-            kubelet_ip,
+        name: format!("default:{}", default),
-        ),
+        authorizations: mk_default_policy(default, cluster_net, kubelet_ip),
         protocol: ProxyProtocol::Detect {
             timeout: detect_timeout,
         },
@@ -77,6 +75,7 @@ async fn incrementally_configure_server() {
     // Check that the watch has been updated to reflect the above change and that this change _only_
     // applies to the correct port.
     let basic_config = InboundServer {
+        name: "srv-0".into(),
         protocol: ProxyProtocol::Http1,
         authorizations: vec![healthcheck_authz(kubelet_ip)].into_iter().collect(),
     };
@@ -103,6 +102,7 @@ async fn incrementally_configure_server() {
     assert_eq!(
         time::timeout(time::Duration::from_secs(1), rx.next()).await,
         Ok(Some(InboundServer {
+            name: "srv-0".into(),
             protocol: ProxyProtocol::Http1,
             authorizations: vec![
                 (
@@ -150,13 +150,14 @@ fn server_update_deselects_pod() {
         (ips.next().unwrap(), ips.next().unwrap())
     };
     let detect_timeout = time::Duration::from_secs(1);
+    let default = DefaultPolicy::Allow {
+        authenticated_only: false,
+        cluster_only: true,
+    };
     let (lookup_rx, mut idx) = Index::new(
         vec![cluster_net],
         "cluster.example.com".into(),
-        DefaultPolicy::Allow {
+        default,
-            authenticated_only: false,
-            cluster_only: true,
-        },
         detect_timeout,
     );
 
@@ -182,6 +183,7 @@ fn server_update_deselects_pod() {
     assert_eq!(
         port2222.get(),
         InboundServer {
+            name: "srv-0".into(),
             protocol: ProxyProtocol::Http2,
             authorizations: vec![healthcheck_authz(kubelet_ip)].into_iter().collect(),
         }
@@ -195,14 +197,8 @@ fn server_update_deselects_pod() {
     assert_eq!(
         port2222.get(),
         InboundServer {
-            authorizations: mk_default_policy(
+            name: format!("default:{}", default),
-                DefaultPolicy::Allow {
+            authorizations: mk_default_policy(default, cluster_net, kubelet_ip),
-                    authenticated_only: false,
-                    cluster_only: true,
-                },
-                cluster_net,
-                kubelet_ip
-            ),
             protocol: ProxyProtocol::Detect {
                 timeout: detect_timeout,
             },
@@ -243,6 +239,7 @@ fn default_policy_global() {
         idx.reset_pods(vec![p]).unwrap();
 
         let config = InboundServer {
+            name: format!("default:{}", default),
             authorizations: mk_default_policy(*default, cluster_net, kubelet_ip),
             protocol: ProxyProtocol::Detect {
                 timeout: detect_timeout,
@@ -300,6 +297,7 @@ fn default_policy_annotated() {
         idx.reset_pods(vec![p]).unwrap();
 
         let config = InboundServer {
+            name: format!("default:{}", default),
             authorizations: mk_default_policy(*default, cluster_net, kubelet_ip),
             protocol: ProxyProtocol::Detect {
                 timeout: detect_timeout,
@@ -323,13 +321,14 @@ fn default_policy_annotated_invalid() {
     };
     let detect_timeout = time::Duration::from_secs(1);
 
+    let default = DefaultPolicy::Allow {
+        authenticated_only: false,
+        cluster_only: false,
+    };
     let (lookup_rx, mut idx) = Index::new(
         vec![cluster_net],
         "cluster.example.com".into(),
-        DefaultPolicy::Allow {
+        default,
-            authenticated_only: false,
-            cluster_only: false,
-        },
         detect_timeout,
     );
 
@@ -353,6 +352,7 @@ fn default_policy_annotated_invalid() {
     assert_eq!(
         port2222.get(),
         InboundServer {
+            name: format!("default:{}", default),
             authorizations: mk_default_policy(
                 DefaultPolicy::Allow {
                     authenticated_only: false,
@@ -400,6 +400,7 @@ fn opaque_annotated() {
         idx.reset_pods(vec![p]).unwrap();
 
         let config = InboundServer {
+            name: format!("default:{}", default),
             authorizations: mk_default_policy(*default, cluster_net, kubelet_ip),
             protocol: ProxyProtocol::Opaque,
         };
@@ -444,21 +445,21 @@ fn authenticated_annotated() {
         );
         idx.reset_pods(vec![p]).unwrap();
 
-        let config = InboundServer {
+        let config = {
-            authorizations: mk_default_policy(
+            let policy = match *default {
-                match *default {
                 DefaultPolicy::Allow { cluster_only, .. } => DefaultPolicy::Allow {
                     cluster_only,
                     authenticated_only: true,
                 },
                 DefaultPolicy::Deny => DefaultPolicy::Deny,
-                },
+            };
-                cluster_net,
+            InboundServer {
-                kubelet_ip,
+                name: format!("default:{}", policy),
-            ),
+                authorizations: mk_default_policy(policy, cluster_net, kubelet_ip),
                 protocol: ProxyProtocol::Detect {
                     timeout: detect_timeout,
                 },
+            }
         };
 
         let port2222 = lookup_rx