js: Move /view to C.

src/httpd.js.c

@@ -41,6 +41,8 @@ static JSValue _authenticate_jwt(tf_ssb_t* ssb, JSContext* context, const char*
 static JSValue _httpd_websocket_upgrade(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
 static const char* _make_session_jwt(JSContext* context, tf_ssb_t* ssb, const char* name);
 static const char* _make_set_session_cookie_header(tf_http_request_t* request, const char* session_cookie);
+const char** _form_data_decode(const char* data, int length);
+const char* _form_data_get(const char** form_data, const char* key);
 
 static JSClassID _httpd_class_id;
 static JSClassID _httpd_request_class_id;
@@ -959,6 +961,123 @@ static void _httpd_endpoint_static(tf_http_request_t* request)
 	tf_file_stat(task, path, _httpd_endpoint_static_stat, request);
 }
 
+typedef struct _view_t
+{
+	tf_http_request_t* request;
+	const char** form_data;
+	void* data;
+	size_t size;
+	bool not_modified;
+} view_t;
+
+static bool _is_filename_safe(const char* filename)
+{
+	if (!filename)
+	{
+		return NULL;
+	}
+	for (const char* p = filename; *p; p++)
+	{
+		if ((*p <= 'a' && *p >= 'z') &&
+			(*p <= 'A' && *p >= 'Z') &&
+			(*p <= '0' && *p >= '9') &&
+			*p != '.' &&
+			*p != '-' &&
+			*p != '_')
+		{
+			return false;
+		}
+	}
+	return strlen(filename) < 256;
+}
+
+static void _httpd_endpoint_view_work(tf_ssb_t* ssb, void* user_data)
+{
+	view_t* view = user_data;
+	tf_http_request_t* request = view->request;
+	char blob_id[256] = "";
+	if (request->path[0] == '/' && request->path[1] == '~')
+	{
+		char user[256] = "";
+		char path[1024] = "";
+		const char* slash = strchr(request->path + 2, '/');
+		if (slash)
+		{
+			snprintf(user, sizeof(user), "%.*s", (int)(slash - (request->path + 2)), request->path + 2);
+			snprintf(path, sizeof(path), "path:%.*s", (int)(strlen(slash + 1) - strlen("/view")), slash + 1);
+			const char* value = tf_ssb_db_get_property(ssb, user, path);
+			snprintf(blob_id, sizeof(blob_id), "%s", value);
+			tf_free((void*)value);
+		}
+	}
+	else if (request->path[0] == '/' && request->path[1] == '&')
+	{
+		snprintf(blob_id, sizeof(blob_id), "%.*s", (int)(strlen(request->path) - strlen("/view") - 1), request->path + 1);
+	}
+
+	if (*blob_id)
+	{
+		const char* if_none_match = tf_http_request_get_header(request, "if-none-match");
+		char match[258];
+		snprintf(match, sizeof(match), "\"%s\"", blob_id);
+		if (if_none_match && strcmp(if_none_match, match))
+		{
+			view->not_modified = true;
+		}
+		else
+		{
+			tf_ssb_db_blob_get(ssb, blob_id, (uint8_t**)&view->data, &view->size);
+		}
+	}
+}
+
+static void _httpd_endpoint_view_after_work(tf_ssb_t* ssb, int status, void* user_data)
+{
+	view_t* view = user_data;
+	const char* filename = _form_data_get(view->form_data, "filename");
+	if (!_is_filename_safe(filename))
+	{
+		filename = NULL;
+	}
+	char content_disposition[512] = "";
+	if (filename)
+	{
+		snprintf(content_disposition, sizeof(content_disposition), "attachment; filename=%s", filename);
+	}
+	const char* headers[] = {
+		"Content-Security-Policy", "sandbox allow-downloads allow-top-navigation-by-user-activation",
+		filename ? "Content-Disposition" : NULL, filename ? content_disposition : NULL,
+	};
+	int count = filename ? tf_countof(headers) / 2 : (tf_countof(headers) / 2 - 1);
+	if (view->not_modified)
+	{
+		tf_http_respond(view->request, 304, headers, count, NULL, 0);
+	}
+	else if (view->data)
+	{
+		tf_http_respond(view->request, 200, headers, count, view->data, view->size);
+		tf_free(view->data);
+	}
+	else
+	{
+		const char* k_payload = tf_http_status_text(404);
+		tf_http_respond(view->request, 404, NULL, 0, k_payload, strlen(k_payload));
+	}
+	tf_free(view->form_data);
+	tf_http_request_unref(view->request);
+	tf_free(view);
+}
+
+static void _httpd_endpoint_view(tf_http_request_t* request)
+{
+	tf_http_request_ref(request);
+	tf_task_t* task = request->user_data;
+	tf_ssb_t* ssb = tf_task_get_ssb(task);
+	view_t* view = tf_malloc(sizeof(view_t));
+	*view = (view_t) { .request = request, .form_data = _form_data_decode(request->query, request->query ? strlen(request->query) : 0) };
+	tf_ssb_run_work(ssb, _httpd_endpoint_view_work, _httpd_endpoint_view_after_work, view);
+}
+
 static void _httpd_endpoint_root_callback(const char* path, void* user_data)
 {
 	tf_http_request_t* request = user_data;
@@ -1690,6 +1809,7 @@ void tf_httpd_register(JSContext* context)
 	tf_http_add_handler(http, "/.well-known/*", _httpd_endpoint_static, NULL, task);
 	tf_http_add_handler(http, "/~*/*/", _httpd_endpoint_static, NULL, task);
 	tf_http_add_handler(http, "/&*.sha256/", _httpd_endpoint_static, NULL, task);
+	tf_http_add_handler(http, "/*/view", _httpd_endpoint_view, NULL, task);
 
 	tf_http_add_handler(http, "/robots.txt", _httpd_endpoint_robots_txt, NULL, NULL);
 	tf_http_add_handler(http, "/debug", _httpd_endpoint_debug, NULL, task);