dnsproxy: Only one copy of the relevant buffers will be made to a TCP request

This copy will be made after scanning the list of nameservers and
only if at least one TCP server is created.
Otherwise, it will be sent an error response to the request.

1 files changed, 38 insertions, 37 deletions

diff --git a/src/dnsproxy.c b/src/dnsproxy.c
index d7ef63bb..fe1ea817 100644
--- a/src/dnsproxy.c
+++ b/src/dnsproxy.c
@@ -2046,11 +2046,9 @@ static struct server_data *create_server(const char *interface,
 		DBG("Adding DNS server %s", data->server);
 
 		server_list = g_slist_append(server_list, data);
-
-		return data;
 	}
 
-	return NULL;
+	return data;
 }
 
 static gboolean resolv(struct request_data *req,
@@ -2345,6 +2343,7 @@ static gboolean tcp_listener_event(GIOChannel *channel, GIOCondition condition,
 	socklen_t client_addr_len = sizeof(client_addr);
 	GSList *list;
 	struct listener_data *ifdata = user_data;
+	int waiting_for_connect = FALSE;
 
 	DBG("condition 0x%x", condition);
 
@@ -2399,7 +2398,6 @@ static gboolean tcp_listener_event(GIOChannel *channel, GIOCondition condition,
 	req->numserv = 0;
 	req->ifdata = (struct listener_data *) ifdata;
 	req->append_domain = FALSE;
-	request_list = g_slist_append(request_list, req);
 
 	for (list = server_list; list; list = list->next) {
 		struct server_data *data = list->data;
@@ -2410,33 +2408,8 @@ static gboolean tcp_listener_event(GIOChannel *channel, GIOCondition condition,
 
 		server = create_server(data->interface, NULL,
 					data->server, IPPROTO_TCP);
-
-		/*
-		 * If server is NULL, we're not connected yet.
-		 * Copy the relevant buffers and continue with
-		 * the next nameserver.
-		 * The request will actually be sent once we're
-		 * properly connected over TCP to this nameserver.
-		 */
-		if (server == NULL) {
-			req->request = g_try_malloc0(req->request_len);
-			if (req->request == NULL)
-				return TRUE;
-
-			memcpy(req->request, buf, req->request_len);
-
-			req->name = g_try_malloc0(sizeof(query));
-			if (req->name == NULL) {
-				g_free(req->request);
-				return TRUE;
-			}
-			memcpy(req->name, query, sizeof(query));
-
+		if (server == NULL)
 			continue;
-		}
-
-		if (req->timeout > 0)
-			g_source_remove(req->timeout);
 
 		for (domains = data->domains; domains;
 				domains = domains->next) {
@@ -2448,15 +2421,43 @@ static gboolean tcp_listener_event(GIOChannel *channel, GIOCondition condition,
 						g_strdup(dom));
 		}
 
-		req->timeout = g_timeout_add_seconds(30, request_timeout, req);
-		if (ns_resolv(server, req, buf, query) > 0) {
-			if (req->timeout > 0) {
-				g_source_remove(req->timeout);
-				req->timeout = 0;
-			}
-		}
+		waiting_for_connect = TRUE;
 	}
 
+	if (waiting_for_connect == FALSE) {
+		/* No server is waiting for connect */
+		send_response(client_sk, buf, len, NULL, 0, IPPROTO_TCP);
+		g_free(req);
+		return TRUE;
+	}
+
+	/*
+	 * The server is not connected yet.
+	 * Copy the relevant buffers.
+	 * The request will actually be sent once we're
+	 * properly connected over TCP to the nameserver.
+	 */
+	req->request = g_try_malloc0(req->request_len);
+	if (req->request == NULL) {
+		send_response(client_sk, buf, len, NULL, 0, IPPROTO_TCP);
+		g_free(req);
+		return TRUE;
+	}
+	memcpy(req->request, buf, req->request_len);
+
+	req->name = g_try_malloc0(sizeof(query));
+	if (req->name == NULL) {
+		send_response(client_sk, buf, len, NULL, 0, IPPROTO_TCP);
+		g_free(req->request);
+		g_free(req);
+		return TRUE;
+	}
+	memcpy(req->name, query, sizeof(query));
+
+	req->timeout = g_timeout_add_seconds(30, request_timeout, req);
+
+	request_list = g_slist_append(request_list, req);
+
 	return TRUE;
 }