fix: restrict asset protocol to vaults

src-tauri/src/asset_scope.rs

@@ -0,0 +1,68 @@
+use std::path::Path;
+use tauri::{AppHandle, Manager, Runtime};
+
+/// Grants asset-protocol access only to a vault selected by the user.
+/// `.helixnotes` is added explicitly because Unix glob matching excludes hidden paths.
+pub fn allow_vault_assets<R: Runtime>(app: &AppHandle<R>, vault_path: &Path) -> Result<(), String> {
+    // Keep the canonical native path: Tauri's scope normalizes Unix paths plus
+    // Windows drive, verbatim, and UNC prefixes when matching asset requests.
+    let vault = std::fs::canonicalize(vault_path).map_err(|error| {
+        format!(
+            "Failed to resolve vault asset path '{}': {error}",
+            vault_path.display()
+        )
+    })?;
+    let scope = app.asset_protocol_scope();
+    scope
+        .allow_directory(&vault, true)
+        .map_err(|error| error.to_string())?;
+    scope
+        .allow_directory(vault.join(".helixnotes"), true)
+        .map_err(|error| error.to_string())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::fs;
+
+    fn test_directory(name: &str) -> std::path::PathBuf {
+        std::env::temp_dir().join(format!("helixnotes-{name}-{}", uuid::Uuid::new_v4()))
+    }
+
+    #[test]
+    fn static_asset_scope_does_not_expose_the_filesystem() {
+        let config: serde_json::Value =
+            serde_json::from_str(include_str!("../tauri.conf.json")).unwrap();
+        let scope = &config["app"]["security"]["assetProtocol"]["scope"];
+
+        assert_eq!(scope["allow"], serde_json::json!([]));
+        assert_eq!(scope["deny"], serde_json::json!([]));
+        assert_eq!(scope["requireLiteralLeadingDot"], true);
+    }
+
+    #[test]
+    fn runtime_scope_allows_only_the_selected_vault() {
+        let root = test_directory("asset-scope");
+        let vault = root.join("Vault [Cross Platform]");
+        let attachments = vault.join(".helixnotes").join("attachments");
+        fs::create_dir_all(&attachments).unwrap();
+        let note_image = vault.join("images").join("note image.png");
+        fs::create_dir_all(note_image.parent().unwrap()).unwrap();
+        fs::write(&note_image, b"image").unwrap();
+        let attachment = attachments.join("attachment.png");
+        fs::write(&attachment, b"attachment").unwrap();
+        let outside = root.join("outside.png");
+        fs::write(&outside, b"outside").unwrap();
+
+        let app = tauri::test::mock_app();
+        allow_vault_assets(app.handle(), &vault).unwrap();
+        let scope = app.asset_protocol_scope();
+
+        assert!(scope.is_allowed(&note_image));
+        assert!(scope.is_allowed(&attachment));
+        assert!(!scope.is_allowed(&outside));
+
+        fs::remove_dir_all(root).unwrap();
+    }
+}