omyacid: default username in /vendor-data

omyacid/src/main.rs

@@ -43,7 +43,6 @@ async fn get_meta_data(
                     inst_name: &inst.name,
                     // XXX: this is very silly imo
                     ssh_pubkeys: ssh_pubkeys.iter().collect(),
-                    username: Some(ctx.cfg().cloud.admin_user.as_ref()),
                 };
 
                 meta.render().map_err(|e| {
@@ -88,6 +87,41 @@ async fn get_user_data(
     }
 }
 
+#[instrument(skip(ctx))]
+async fn get_vendor_data(
+    State(ctx): State<ctx::Context>,
+    ConnectInfo(addr): ConnectInfo<SocketAddr>,
+) -> Result<String, StatusCode> {
+    tracing::info!("Handling /vendor-data");
+
+    // All of the vendor data so far is handled globally, so this isn't really
+    // necessary. But it might help avoid an attacker trying to sniff for the
+    // admin username from an unknown instance.
+    if let IpAddr::V4(ip) = addr.ip() {
+        match ctx.get_instance(ip).await {
+            Ok(_) => {
+                let data = model::VendorData {
+                    username: Some(&ctx.cfg().cloud.admin_user),
+                };
+                data.render().map_err(|e| {
+                    tracing::error!("Renderer error: {e}");
+                    StatusCode::INTERNAL_SERVER_ERROR
+                })
+            }
+            Err(err) => {
+                tracing::error!("{err}");
+                Err(StatusCode::INTERNAL_SERVER_ERROR)
+            }
+            _ => {
+                tracing::warn!("Request from unregistered server {ip}");
+                Err(StatusCode::FORBIDDEN)
+            }
+        }
+    } else {
+        Err(StatusCode::BAD_REQUEST)
+    }
+}
+
 async fn ignored() -> &'static str {
     ""
 }
@@ -131,7 +165,7 @@ async fn main() -> ExitCode {
     let app = Router::new()
         .route("/meta-data", get(get_meta_data))
         .route("/user-data", get(get_user_data))
-        .route("/vendor-data", get(ignored))
+        .route("/vendor-data", get(get_vendor_data))
         .route("/network-config", get(ignored))
         .with_state(ctx);
     if let Err(err) = axum::serve(

omyacid/src/model.rs

@@ -4,5 +4,10 @@ use askama::Template;
 pub struct Metadata<'a> {
     pub inst_name: &'a str,
     pub ssh_pubkeys: Vec<&'a String>,
+}
+
+#[derive(Template)]
+#[template(path = "vendor-data.yml")]
+pub struct VendorData<'a> {
     pub username: Option<&'a str>,
 }

omyacid/templates/meta-data.yml

@@ -5,9 +5,4 @@ public-keys:
 {% for key in ssh_pubkeys -%}
 - "{{ key }}"
 {% endfor %}
-{%- endif -%}
-{% if let Some(user) = username -%}
-system_info:
-  default_user:
-    name: "{{ user }}"
-{%- endif %}
+{%- endif -%}

omyacid/templates/vendor-data.yml

@@ -0,0 +1,6 @@
+#cloud-config
+{% if let Some(user) = username -%}
+system_info:
+  default_user:
+    name: "{{ user }}"
+{%- endif %}