route-manager: remember routes that should be active

Kernel likes to remove a route in case an equivalent route is added to another
interface. Avoid this situation and only apply the new routes in case the ones
that would cause a conflict are removed.

https://bugzilla.redhat.com/show_bug.cgi?id=1164441
https://bugzilla.gnome.org/show_bug.cgi?id=740064

1 files changed, 172 insertions, 38 deletions

diff --git a/src/nm-route-manager.c b/src/nm-route-manager.c
index a1fae89575..925de7760f 100644
--- a/src/nm-route-manager.c
+++ b/src/nm-route-manager.c
@@ -18,6 +18,7 @@
  * Copyright (C) 2015 Red Hat, Inc.
  */
 
+#include <string.h>
 
 #include "config.h"
 
@@ -27,12 +28,19 @@
 
 #include "NetworkManagerUtils.h"
 
+typedef struct {
+	GArray *ip4_routes;
+	GArray *ip6_routes;
+} NMRouteManagerPrivate;
+
+#define NM_ROUTE_MANAGER_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), NM_TYPE_ROUTE_MANAGER, NMRouteManagerPrivate))
+
 G_DEFINE_TYPE (NMRouteManager, nm_route_manager, G_TYPE_OBJECT)
 
 static NMRouteManager *_instance;
 
-static gboolean
-array_contains_ip4_route (const GArray *routes, const NMPlatformIP4Route *route)
+static const NMPlatformIP4Route *
+array_get_ip4_route (const GArray *routes, int ifindex, const NMPlatformIP4Route *route)
 {
 	guint len = routes ? routes->len : 0;
 	guint i;
@@ -40,18 +48,25 @@ array_contains_ip4_route (const GArray *routes, const NMPlatformIP4Route *route)
 	for (i = 0; i < len; i++) {
 		NMPlatformIP4Route *c = &g_array_index (routes, NMPlatformIP4Route, i);
 
+		if (ifindex) {
+			/* Looking for a specific route. */
+			if (   c->ifindex != ifindex
+		            || route->mss != c->mss
+			    || route->gateway != c->gateway)
+			continue;
+		}
+
 		if (route->network == c->network &&
 		    route->plen == c->plen &&
-		    route->gateway == c->gateway &&
 		    route->metric == c->metric)
-			return TRUE;
+			return c;
 	}
 
-	return FALSE;
+	return NULL;
 }
 
-static gboolean
-array_contains_ip6_route (const GArray *routes, const NMPlatformIP6Route *route)
+static const NMPlatformIP6Route *
+array_get_ip6_route (const GArray *routes, int ifindex, const NMPlatformIP6Route *route)
 {
 	guint len = routes ? routes->len : 0;
 	guint i;
@@ -61,14 +76,21 @@ array_contains_ip6_route (const GArray *routes, const NMPlatformIP6Route *route)
 		int route_metric = nm_utils_ip6_route_metric_normalize (route->metric);
 		int c_metric = nm_utils_ip6_route_metric_normalize (c->metric);
 
+		if (ifindex) {
+			/* Looking for a specific route. */
+			if (   c->ifindex != ifindex
+		            || route->mss != c->mss
+			    || !IN6_ARE_ADDR_EQUAL (&route->gateway, &c->gateway))
+				continue;
+		}
+
 		if (IN6_ARE_ADDR_EQUAL (&route->network, &c->network) &&
 		    route->plen == c->plen &&
-		    IN6_ARE_ADDR_EQUAL (&route->gateway, &c->gateway) &&
 		    route_metric == c_metric)
-			return TRUE;
+			return c;
 	}
 
-	return FALSE;
+	return NULL;
 }
 
 
@@ -88,31 +110,76 @@ array_contains_ip6_route (const GArray *routes, const NMPlatformIP6Route *route)
 gboolean
 nm_route_manager_ip4_route_sync (NMRouteManager *self, int ifindex, const GArray *known_routes)
 {
-	GArray *routes;
-	NMPlatformIP4Route *route;
+	NMRouteManagerPrivate *priv = NM_ROUTE_MANAGER_GET_PRIVATE (self);
+	GArray *plat_routes, *routes = priv->ip4_routes;
+	NMPlatformIP4Route route;
 	const NMPlatformIP4Route *known_route;
+	const NMPlatformIP4Route *existing;
 	gboolean success;
 	int i, i_type;
 
+	/* Learn about routes that platform knows but we don't. */
+	plat_routes = nm_platform_ip4_route_get_all (0, NM_PLATFORM_GET_ROUTE_MODE_NO_DEFAULT);
+	for (i = 0; i < plat_routes->len; i++) {
+		existing = &g_array_index (plat_routes, NMPlatformIP4Route, i);
+		if (!array_get_ip4_route (routes, existing->ifindex, existing))
+			g_array_append_val (routes, *existing);
+	}
+
 	/* Delete unknown routes */
-	routes = nm_platform_ip4_route_get_all (ifindex, NM_PLATFORM_GET_ROUTE_MODE_NO_DEFAULT);
-	for (i = 0; i < routes->len; i++) {
-		route = &g_array_index (routes, NMPlatformIP4Route, i);
+	for (i = 0; i < routes->len;) {
+		route = g_array_index (routes, NMPlatformIP4Route, i);
+
+		if (route.ifindex == ifindex) {
+			/* Our route. Keep it? */
+			if (array_get_ip4_route (known_routes, route.ifindex, &route)) {
+				i++;
+				continue;
+			}
+
+			g_array_remove_index (routes, i);
+		} else {
+			i++;
+		}
 
-		if (!array_contains_ip4_route (known_routes, route))
-			(void) nm_platform_ip4_route_delete (ifindex, route->network, route->plen, route->metric);
+		existing = array_get_ip4_route (routes, 0, &route);
+		if (   existing
+		    && !array_get_ip4_route (plat_routes, existing->ifindex, existing)) {
+			/* The route that should already exist is not there.
+			 * Try to add it. */
+			nm_platform_ip4_route_add (existing->ifindex,
+			                           existing->source,
+			                           existing->network,
+			                           existing->plen,
+			                           existing->gateway,
+			                           0,
+			                           existing->metric,
+			                           existing->mss);
+
+			/* It's now hopefully in platform. Take a note so that we
+			 * don't attempt to add it again. */
+			g_array_append_val (plat_routes, *existing);
+		}
+
+		if (route.ifindex == ifindex) {
+			/* Clean up. */
+			nm_platform_ip4_route_delete (route.ifindex,
+			                              route.network,
+			                              route.plen,
+			                              route.metric);
+		}
 	}
 
-	if (!known_routes) {
-		g_array_free (routes, TRUE);
+	if (!known_routes)
 		return TRUE;
-	}
 
 	/* Add missing routes */
 	for (i_type = 0, success = TRUE; i_type < 2 && success; i_type++) {
 		for (i = 0; i < known_routes->len && success; i++) {
 			known_route = &g_array_index (known_routes, NMPlatformIP4Route, i);
 
+			g_assert (known_route->ifindex);
+
 			if (NM_PLATFORM_IP_ROUTE_IS_DEFAULT (known_route))
 				continue;
 
@@ -123,8 +190,8 @@ nm_route_manager_ip4_route_sync (NMRouteManager *self, int ifindex, const GArray
 			}
 
 			/* Ignore routes that already exist */
-			if (!array_contains_ip4_route (routes, known_route)) {
-				success = nm_platform_ip4_route_add (ifindex,
+			if (!array_get_ip4_route (routes, 0, known_route)) {
+				success = nm_platform_ip4_route_add (known_route->ifindex,
 				                                     known_route->source,
 				                                     known_route->network,
 				                                     known_route->plen,
@@ -138,10 +205,12 @@ nm_route_manager_ip4_route_sync (NMRouteManager *self, int ifindex, const GArray
 					success = TRUE;
 				}
 			}
+
+			if (!array_get_ip4_route (routes, known_route->ifindex, known_route))
+				g_array_append_val (routes, *known_route);
 		}
 	}
 
-	g_array_free (routes, TRUE);
 	return success;
 }
 
@@ -161,32 +230,74 @@ nm_route_manager_ip4_route_sync (NMRouteManager *self, int ifindex, const GArray
 gboolean
 nm_route_manager_ip6_route_sync (NMRouteManager *self, int ifindex, const GArray *known_routes)
 {
-	GArray *routes;
-	NMPlatformIP6Route *route;
+	NMRouteManagerPrivate *priv = NM_ROUTE_MANAGER_GET_PRIVATE (self);
+	GArray *plat_routes, *routes = priv->ip6_routes;
+	NMPlatformIP6Route route;
 	const NMPlatformIP6Route *known_route;
+	const NMPlatformIP6Route *existing;
 	gboolean success;
 	int i, i_type;
 
-	/* Delete unknown routes */
-	routes = nm_platform_ip6_route_get_all (ifindex, NM_PLATFORM_GET_ROUTE_MODE_NO_DEFAULT);
-	for (i = 0; i < routes->len; i++) {
-		route = &g_array_index (routes, NMPlatformIP6Route, i);
-		route->ifindex = 0;
+	/* Learn about routes that platform knows but we don't. */
+	plat_routes = nm_platform_ip6_route_get_all (0, NM_PLATFORM_GET_ROUTE_MODE_NO_DEFAULT);
+	for (i = 0; i < plat_routes->len; i++) {
+		existing = &g_array_index (plat_routes, NMPlatformIP6Route, i);
+		if (!array_get_ip6_route (routes, existing->ifindex, existing))
+			g_array_append_val (routes, *existing);
+	}
 
-		if (!array_contains_ip6_route (known_routes, route))
-			nm_platform_ip6_route_delete (ifindex, route->network, route->plen, route->metric);
+	for (i = 0; i < routes->len;) {
+		route = g_array_index (routes, NMPlatformIP6Route, i);
+
+		if (route.ifindex == ifindex) {
+			/* Our route. Keep it? */
+			if (array_get_ip6_route (known_routes, route.ifindex, &route)) {
+				i++;
+				continue;
+			}
+
+			g_array_remove_index (routes, i);
+		} else {
+			i++;
+		}
+
+		existing = array_get_ip6_route (routes, 0, &route);
+		if (    existing
+		    && !array_get_ip6_route (plat_routes, existing->ifindex, existing)) {
+			/* The route that should already exist is not there.
+			 * Try to add it. */
+			nm_platform_ip6_route_add (existing->ifindex,
+			                           existing->source,
+			                           existing->network,
+			                           existing->plen,
+			                           existing->gateway,
+			                           existing->metric,
+			                           existing->mss);
+
+			/* It's now hopefully in platform. Take a note so that we
+			 * don't attempt to add it again. */
+			g_array_append_val (plat_routes, *existing);
+		}
+
+		if (route.ifindex == ifindex) {
+			/* Clean up. */
+			nm_platform_ip6_route_delete (route.ifindex,
+			                              route.network,
+			                              route.plen,
+			                              route.metric);
+		}
 	}
 
-	if (!known_routes) {
-		g_array_free (routes, TRUE);
+	if (!known_routes)
 		return TRUE;
-	}
 
 	/* Add missing routes */
 	for (i_type = 0, success = TRUE; i_type < 2 && success; i_type++) {
 		for (i = 0; i < known_routes->len && success; i++) {
 			known_route = &g_array_index (known_routes, NMPlatformIP6Route, i);
 
+			g_assert (known_route->ifindex);
+
 			if (NM_PLATFORM_IP_ROUTE_IS_DEFAULT (known_route))
 				continue;
 
@@ -197,8 +308,8 @@ nm_route_manager_ip6_route_sync (NMRouteManager *self, int ifindex, const GArray
 			}
 
 			/* Ignore routes that already exist */
-			if (!array_contains_ip6_route (routes, known_route)) {
-				success = nm_platform_ip6_route_add (ifindex,
+			if (!array_get_ip6_route (routes, 0, known_route)) {
+				success = nm_platform_ip6_route_add (known_route->ifindex,
 				                                     known_route->source,
 				                                     known_route->network,
 				                                     known_route->plen,
@@ -211,10 +322,12 @@ nm_route_manager_ip6_route_sync (NMRouteManager *self, int ifindex, const GArray
 					success = TRUE;
 				}
 			}
+
+			if (!array_get_ip6_route (routes, known_route->ifindex, known_route))
+				g_array_append_val (routes, *known_route);
 		}
 	}
 
-	g_array_free (routes, TRUE);
 	return success;
 }
 
@@ -238,9 +351,30 @@ nm_route_manager_get ()
 static void
 nm_route_manager_init (NMRouteManager *self)
 {
+	NMRouteManagerPrivate *priv = NM_ROUTE_MANAGER_GET_PRIVATE (self);
+
+	priv->ip4_routes = g_array_new (FALSE, FALSE, sizeof (NMPlatformIP4Route));
+	priv->ip6_routes = g_array_new (FALSE, FALSE, sizeof (NMPlatformIP6Route));
+}
+
+static void
+finalize (GObject *object)
+{
+	NMRouteManagerPrivate *priv = NM_ROUTE_MANAGER_GET_PRIVATE (object);
+
+	g_array_free (priv->ip4_routes, TRUE);
+	g_array_free (priv->ip6_routes, TRUE);
+
+	G_OBJECT_CLASS (nm_route_manager_parent_class)->finalize (object);
 }
 
 static void
 nm_route_manager_class_init (NMRouteManagerClass *klass)
 {
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	g_type_class_add_private (klass, sizeof (NMRouteManagerPrivate));
+
+	/* virtual methods */
+	object_class->finalize = finalize;
 }