Add YAML-configured ACLs with Basic and IP authorization

src/metrics.rs

@@ -15,6 +15,7 @@ pub(crate) struct Metrics {
     active_tunnels: UpDownCounter<i64>,
     tunnel_duration: Histogram<f64>,
     tunnel_bytes: Counter<u64>,
+    acl_decisions: Counter<u64>,
 }
 
 impl Metrics {
@@ -60,6 +61,11 @@ impl Metrics {
                 .with_description("Bytes relayed through completed CONNECT tunnels")
                 .with_unit("By")
                 .build(),
+            acl_decisions: meter
+                .u64_counter("hermes.proxy.acl.decisions")
+                .with_description("Number of ACL decisions by outcome and reason")
+                .with_unit("{decision}")
+                .build(),
         }
     }
 
@@ -122,6 +128,16 @@ impl Metrics {
         );
     }
 
+    pub fn acl_decision(&self, decision: &str, reason: &str) {
+        self.acl_decisions.add(
+            1,
+            &[
+                KeyValue::new("acl.decision", decision.to_owned()),
+                KeyValue::new("acl.reason", reason.to_owned()),
+            ],
+        );
+    }
+
     pub fn tunnel_started(&self) -> ActiveTunnel {
         self.active_tunnels.add(1, &[]);
         ActiveTunnel {