Fix autonomous ME recovery from Direct fallback

Co-Authored-By: brekotis <93345790+brekotis@users.noreply.github.com>

src/config/defaults.rs

@@ -59,7 +59,7 @@ const DEFAULT_ME_POOL_DRAIN_SOFT_EVICT_BUDGET_PER_CORE: u16 = 16;
 const DEFAULT_ME_POOL_DRAIN_SOFT_EVICT_COOLDOWN_MS: u64 = 1000;
 const DEFAULT_USER_MAX_UNIQUE_IPS_WINDOW_SECS: u64 = 30;
 const DEFAULT_ACCEPT_PERMIT_TIMEOUT_MS: u64 = 250;
-const DEFAULT_CONNTRACK_CONTROL_ENABLED: bool = true;
+const DEFAULT_CONNTRACK_CONTROL_ENABLED: bool = false;
 const DEFAULT_CONNTRACK_PRESSURE_HIGH_WATERMARK_PCT: u8 = 85;
 const DEFAULT_CONNTRACK_PRESSURE_LOW_WATERMARK_PCT: u8 = 70;
 const DEFAULT_CONNTRACK_DELETE_BUDGET_PER_SEC: u64 = 4096;
@@ -244,6 +244,7 @@ pub(crate) fn default_accept_permit_timeout_ms() -> u64 {
     DEFAULT_ACCEPT_PERMIT_TIMEOUT_MS
 }
 
+/// Keeps privileged conntrack control disabled unless explicitly requested.
 pub(crate) fn default_conntrack_control_enabled() -> bool {
     DEFAULT_CONNTRACK_CONTROL_ENABLED
 }

src/config/tests/load_basic_tests/conntrack_tests.rs

@@ -1,5 +1,71 @@
 use super::*;
 
+#[test]
+fn conntrack_control_is_opt_in_by_default() {
+    assert!(!default_conntrack_control_enabled());
+    assert!(
+        !ProxyConfig::default()
+            .server
+            .conntrack_control
+            .inline_conntrack_control
+    );
+    let cfg = load_config_from_temp_toml(
+        r#"
+        [censorship]
+        tls_domain = "example.com"
+
+        [access.users]
+        user = "00000000000000000000000000000000"
+        "#,
+    );
+    assert!(!cfg.server.conntrack_control.inline_conntrack_control);
+    assert!(
+        !cfg.server
+            .conntrack_control
+            .inline_conntrack_control_explicit
+    );
+    assert_eq!(
+        serde_json::to_value(&cfg.server.conntrack_control).unwrap()["inline_conntrack_control"],
+        false,
+    );
+}
+
+#[test]
+fn conntrack_control_preserves_explicit_enablement() {
+    for enabled in [false, true] {
+        let cfg = load_config_from_temp_toml(&format!(
+            r#"
+            [server.conntrack_control]
+            inline_conntrack_control = {enabled}
+            backend = "nftables"
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+            "#,
+        ));
+        assert_eq!(
+            cfg.server.conntrack_control.inline_conntrack_control,
+            enabled
+        );
+        assert!(
+            cfg.server
+                .conntrack_control
+                .inline_conntrack_control_explicit
+        );
+        assert_eq!(
+            cfg.server.conntrack_control.backend,
+            ConntrackBackend::Nftables
+        );
+        assert_eq!(
+            serde_json::to_value(&cfg.server.conntrack_control).unwrap()["inline_conntrack_control"],
+            enabled,
+        );
+    }
+}
+
 #[test]
 fn conntrack_pressure_high_watermark_out_of_range_is_rejected() {
     let toml = r#"