platform: extend API for adding routes

Via the flags of the RTM_NEWROUTE netlink message, kernel and iproute2
support various variants to add a route.

 - ip route add
 - ip route change
 - ip route replace
 - ip route prepend
 - ip route append
 - ip route test

Previously, our nm_platform_ip4_route_add() function was basically
`ip route replace`. In the future, we should rather user `ip route
append` instead.

Anyway, expose the netlink message flags in the API. This allows to
use the various forms, and makes it also more apparent to the user that
they even exist.

9 files changed, 138 insertions, 105 deletions

diff --git a/src/nm-default-route-manager.c b/src/nm-default-route-manager.c
index eeaf38fc4e..d80d39450f 100644
--- a/src/nm-default-route-manager.c
+++ b/src/nm-default-route-manager.c
@@ -304,7 +304,7 @@ _platform_route_sync_add (const VTableIP *vtable, NMDefaultRouteManager *self, g
 		rt.plen = 0;
 		rt.metric = entry->effective_metric;
 
-		success = nm_platform_ip4_route_add (priv->platform, &rt);
+		success = nm_platform_ip4_route_add (priv->platform, NMP_NLM_FLAG_REPLACE, &rt);
 	} else {
 		NMPlatformIP6Route rt = entry->route.r6;
 
@@ -312,7 +312,7 @@ _platform_route_sync_add (const VTableIP *vtable, NMDefaultRouteManager *self, g
 		rt.plen = 0;
 		rt.metric = entry->effective_metric;
 
-		success = nm_platform_ip6_route_add (priv->platform, &rt);
+		success = nm_platform_ip6_route_add (priv->platform, NMP_NLM_FLAG_REPLACE, &rt);
 	}
 	if (!success) {
 		_LOGW (vtable->vt->addr_family, "failed to add default route %s with effective metric %u",
diff --git a/src/nm-route-manager.c b/src/nm-route-manager.c
index 07947d790c..ebd0594fb5 100644
--- a/src/nm-route-manager.c
+++ b/src/nm-route-manager.c
@@ -896,15 +896,16 @@ next:
 					gateway_routes = g_array_new (FALSE, FALSE, sizeof (guint));
 				g_array_append_val (gateway_routes, i_ipx_routes);
 			} else
-				vtable->vt->route_add (priv->platform, 0, cur_ipx_route, *p_effective_metric);
+				vtable->vt->route_add (priv->platform, NMP_NLM_FLAG_REPLACE,
+				                       cur_ipx_route, 0, *p_effective_metric);
 		}
 
 		if (gateway_routes) {
 			for (i = 0; i < gateway_routes->len; i++) {
 				i_ipx_routes = g_array_index (gateway_routes, guint, i);
-				vtable->vt->route_add (priv->platform, 0,
+				vtable->vt->route_add (priv->platform, NMP_NLM_FLAG_REPLACE,
 				                       ipx_routes->index->entries[i_ipx_routes],
-				                       effective_metrics[i_ipx_routes]);
+				                       0, effective_metrics[i_ipx_routes]);
 			}
 			g_array_unref (gateway_routes);
 		}
@@ -953,7 +954,8 @@ next:
 			    || route_dest_cmp_result != 0
 			    || !_route_equals_ignoring_ifindex (vtable, cur_plat_route, cur_ipx_route, *p_effective_metric)) {
 
-				if (!vtable->vt->route_add (priv->platform, ifindex, cur_ipx_route, *p_effective_metric)) {
+				if (!vtable->vt->route_add (priv->platform, NMP_NLM_FLAG_REPLACE,
+				                            cur_ipx_route, ifindex, *p_effective_metric)) {
 					if (cur_ipx_route->rx.rt_source < NM_IP_CONFIG_SOURCE_USER) {
 						_LOGD (vtable->vt->addr_family,
 						       "ignore error adding IPv%c route to kernel: %s",
diff --git a/src/platform/nm-fake-platform.c b/src/platform/nm-fake-platform.c
index f817bfb571..338b022e79 100644
--- a/src/platform/nm-fake-platform.c
+++ b/src/platform/nm-fake-platform.c
@@ -1192,7 +1192,10 @@ ip_route_delete (NMPlatform *platform, const NMPObject *obj)
 }
 
 static gboolean
-ipx_route_add (NMPlatform *platform, int addr_family, const NMPlatformObject *route)
+ip_route_add (NMPlatform *platform,
+              NMPNlmFlags flags,
+              int addr_family,
+              const NMPlatformIPRoute *route)
 {
 	NMDedupMultiIter iter;
 	nm_auto_nmpobj NMPObject *obj = NULL;
@@ -1208,10 +1211,13 @@ ipx_route_add (NMPlatform *platform, int addr_family, const NMPlatformObject *ro
 
 	g_assert (NM_IN_SET (addr_family, AF_INET, AF_INET6));
 
+	/* currently, only replace is implemented. */
+	g_assert (flags == NMP_NLM_FLAG_REPLACE);
+
 	obj = nmp_object_new (addr_family == AF_INET
 	                        ? NMP_OBJECT_TYPE_IP4_ROUTE
 	                        : NMP_OBJECT_TYPE_IP6_ROUTE,
-	                      route);
+	                      (const NMPlatformObject *) route);
 	rt = &obj->ip_route;
 	rt->rt_source = nmp_utils_ip_config_source_round_trip_rtprot (rt->rt_source);
 
@@ -1274,18 +1280,6 @@ ipx_route_add (NMPlatform *platform, int addr_family, const NMPlatformObject *ro
 	return TRUE;
 }
 
-static gboolean
-ip4_route_add (NMPlatform *platform, const NMPlatformIP4Route *route)
-{
-	return ipx_route_add (platform, AF_INET, (const NMPlatformObject *) route);
-}
-
-static gboolean
-ip6_route_add (NMPlatform *platform, const NMPlatformIP6Route *route)
-{
-	return ipx_route_add (platform, AF_INET6, (const NMPlatformObject *) route);
-}
-
 /*****************************************************************************/
 
 static void
@@ -1396,7 +1390,6 @@ nm_fake_platform_class_init (NMFakePlatformClass *klass)
 	platform_class->ip4_address_delete = ip4_address_delete;
 	platform_class->ip6_address_delete = ip6_address_delete;
 
-	platform_class->ip4_route_add = ip4_route_add;
-	platform_class->ip6_route_add = ip6_route_add;
+	platform_class->ip_route_add = ip_route_add;
 	platform_class->ip_route_delete = ip_route_delete;
 }
diff --git a/src/platform/nm-linux-platform.c b/src/platform/nm-linux-platform.c
index 3722c90319..42a77c5066 100644
--- a/src/platform/nm-linux-platform.c
+++ b/src/platform/nm-linux-platform.c
@@ -2430,7 +2430,7 @@ ip_route_get_lock_flag (const NMPlatformIPRoute *route)
 /* Copied and modified from libnl3's build_route_msg() and rtnl_route_build_msg(). */
 static struct nl_msg *
 _nl_msg_new_route (int nlmsg_type,
-                   int nlmsg_flags,
+                   NMPNlmFlags nlmsgflags,
                    const NMPObject *obj)
 {
 	struct nl_msg *msg;
@@ -2460,7 +2460,8 @@ _nl_msg_new_route (int nlmsg_type,
 	nm_assert (NM_IN_SET (NMP_OBJECT_GET_TYPE (obj), NMP_OBJECT_TYPE_IP4_ROUTE, NMP_OBJECT_TYPE_IP6_ROUTE));
 	nm_assert (NM_IN_SET (nlmsg_type, RTM_NEWROUTE, RTM_DELROUTE));
 
-	msg = nlmsg_alloc_simple (nlmsg_type, nlmsg_flags);
+	nm_assert (((NMPNlmFlags) ((int) nlmsgflags)) == nlmsgflags);
+	msg = nlmsg_alloc_simple (nlmsg_type, (int) nlmsgflags);
 	if (!msg)
 		g_return_val_if_reached (NULL);
 
@@ -5699,41 +5700,39 @@ ip6_address_delete (NMPlatform *platform, int ifindex, struct in6_addr addr, gui
 /*****************************************************************************/
 
 static gboolean
-ip4_route_add (NMPlatform *platform, const NMPlatformIP4Route *route)
+ip_route_add (NMPlatform *platform,
+              NMPNlmFlags flags,
+              int addr_family,
+              const NMPlatformIPRoute *route)
 {
-	NMPObject obj;
-	NMPlatformIP4Route *r;
 	nm_auto_nlmsg struct nl_msg *nlmsg = NULL;
-
-	nmp_object_stackinit (&obj, NMP_OBJECT_TYPE_IP4_ROUTE, (const NMPlatformObject *) route);
-	r = NMP_OBJECT_CAST_IP4_ROUTE (&obj);
-	r->network = nm_utils_ip4_address_clear_host_address (r->network, r->plen);
-	r->rt_source = nmp_utils_ip_config_source_round_trip_rtprot (r->rt_source),
-	r->scope_inv = nm_platform_route_scope_inv (!r->gateway
-	                                            ? RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
-
-	nlmsg = _nl_msg_new_route (RTM_NEWROUTE,
-	                           NLM_F_CREATE | NLM_F_REPLACE,
-	                           &obj);
-	return do_add_addrroute (platform, &obj, nlmsg);
-}
-
-static gboolean
-ip6_route_add (NMPlatform *platform, const NMPlatformIP6Route *route)
-{
 	NMPObject obj;
-	NMPlatformIP6Route *r;
-	nm_auto_nlmsg struct nl_msg *nlmsg = NULL;
-
-	nmp_object_stackinit (&obj, NMP_OBJECT_TYPE_IP6_ROUTE, (const NMPlatformObject *) route);
-	r = NMP_OBJECT_CAST_IP6_ROUTE (&obj);
-	nm_utils_ip6_address_clear_host_address (&r->network, &r->network, r->plen);
-	r->rt_source = nmp_utils_ip_config_source_round_trip_rtprot (r->rt_source),
-	nm_utils_ip6_address_clear_host_address (&r->src, &r->src, r->src_plen);
+	NMPlatformIP4Route *r4;
+	NMPlatformIP6Route *r6;
+
+	switch (addr_family) {
+	case AF_INET:
+		nmp_object_stackinit (&obj, NMP_OBJECT_TYPE_IP4_ROUTE, (const NMPlatformObject *) route);
+		r4 = NMP_OBJECT_CAST_IP4_ROUTE (&obj);
+		r4->network = nm_utils_ip4_address_clear_host_address (r4->network, r4->plen);
+		r4->rt_source = nmp_utils_ip_config_source_round_trip_rtprot (r4->rt_source),
+		r4->scope_inv = nm_platform_route_scope_inv (!r4->gateway
+		                                             ? RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
+		break;
+	case AF_INET6:
+		nmp_object_stackinit (&obj, NMP_OBJECT_TYPE_IP6_ROUTE, (const NMPlatformObject *) route);
+		r6 = NMP_OBJECT_CAST_IP6_ROUTE (&obj);
+		nm_utils_ip6_address_clear_host_address (&r6->network, &r6->network, r6->plen);
+		r6->rt_source = nmp_utils_ip_config_source_round_trip_rtprot (r6->rt_source),
+		nm_utils_ip6_address_clear_host_address (&r6->src, &r6->src, r6->src_plen);
+		break;
+	default:
+		nm_assert_not_reached ();
+	}
 
-	nlmsg = _nl_msg_new_route (RTM_NEWROUTE,
-	                           NLM_F_CREATE | NLM_F_REPLACE,
-	                           &obj);
+	nlmsg = _nl_msg_new_route (RTM_NEWROUTE, flags, &obj);
+	if (!nlmsg)
+		g_return_val_if_reached (FALSE);
 	return do_add_addrroute (platform, &obj, nlmsg);
 }
 
@@ -5781,11 +5780,9 @@ ip_route_delete (NMPlatform *platform,
 		}
 	}
 
-	nlmsg = _nl_msg_new_route (RTM_DELROUTE,
-	                           0,
-	                           obj);
+	nlmsg = _nl_msg_new_route (RTM_DELROUTE, 0, obj);
 	if (!nlmsg)
-		return FALSE;
+		g_return_val_if_reached (FALSE);
 	return do_delete_object (platform, obj, nlmsg);
 }
 
@@ -6516,8 +6513,7 @@ nm_linux_platform_class_init (NMLinuxPlatformClass *klass)
 	platform_class->ip4_address_delete = ip4_address_delete;
 	platform_class->ip6_address_delete = ip6_address_delete;
 
-	platform_class->ip4_route_add = ip4_route_add;
-	platform_class->ip6_route_add = ip6_route_add;
+	platform_class->ip_route_add = ip_route_add;
 	platform_class->ip_route_delete = ip_route_delete;
 
 	platform_class->check_support_kernel_extended_ifa_flags = check_support_kernel_extended_ifa_flags;
diff --git a/src/platform/nm-platform.c b/src/platform/nm-platform.c
index 0386981eba..03dc6943b6 100644
--- a/src/platform/nm-platform.c
+++ b/src/platform/nm-platform.c
@@ -3409,53 +3409,60 @@ nm_platform_address_flush (NMPlatform *self, int ifindex)
 
 /*****************************************************************************/
 
-/**
- * nm_platform_ip4_route_add:
- * @self:
- * @route:
- *
- * For kernel, a gateway can be either explicitly set or left
- * at zero (0.0.0.0). In addition, there is the scope of the IPv4
- * route.
- * When adding a route with
- *   $ ip route add default dev $IFNAME
- * the resulting route will have gateway 0.0.0.0 and scope "link".
- * Contrary to
- *   $ ip route add default via 0.0.0.0 dev $IFNAME
- * which adds the route with scope "global".
- *
- * NetworkManager's Platform can currently only add on-link-routes with scope
- * "link" (and gateway 0.0.0.0) or gateway-routes with scope "global" (and
- * gateway not 0.0.0.0).
- *
- * It does not support adding globally scoped routes via 0.0.0.0.
- *
- * Returns: %TRUE in case of success.
- */
+NM_UTILS_LOOKUP_STR_DEFINE_STATIC (_nmp_nlm_flag_to_string_lookup, NMPNlmFlags,
+	NM_UTILS_LOOKUP_DEFAULT (NULL),
+	NM_UTILS_LOOKUP_ITEM (NMP_NLM_FLAG_ADD,     "add"),
+	NM_UTILS_LOOKUP_ITEM (NMP_NLM_FLAG_CHANGE,  "change"),
+	NM_UTILS_LOOKUP_ITEM (NMP_NLM_FLAG_REPLACE, "replace"),
+	NM_UTILS_LOOKUP_ITEM (NMP_NLM_FLAG_PREPEND, "prepend"),
+	NM_UTILS_LOOKUP_ITEM (NMP_NLM_FLAG_APPEND,  "append"),
+	NM_UTILS_LOOKUP_ITEM (NMP_NLM_FLAG_TEST,    "test"),
+	NM_UTILS_LOOKUP_ITEM_IGNORE (NMP_NLM_FLAG_F_APPEND),
+);
+
+#define _nmp_nlm_flag_to_string(flags) \
+	({ \
+		NMPNlmFlags _flags = (flags); \
+		\
+		_nmp_nlm_flag_to_string_lookup (flags) ?: nm_sprintf_bufa (100, "new[0x%x]", (unsigned) _flags); \
+	})
+
 gboolean
-nm_platform_ip4_route_add (NMPlatform *self, const NMPlatformIP4Route *route)
+nm_platform_ip4_route_add (NMPlatform *self,
+                           NMPNlmFlags flags,
+                           const NMPlatformIP4Route *route)
 {
+	char sbuf[sizeof (_nm_utils_to_string_buffer)];
+
 	_CHECK_SELF (self, klass, FALSE);
 
 	g_return_val_if_fail (route, FALSE);
 	g_return_val_if_fail (route->plen <= 32, FALSE);
 
-	_LOGD ("route: adding or updating IPv4 route: %s", nm_platform_ip4_route_to_string (route, NULL, 0));
+	_LOGD ("route: %-10s IPv4 route: %s",
+	       _nmp_nlm_flag_to_string (flags),
+	       nm_platform_ip4_route_to_string (route, sbuf, sizeof (sbuf)));
 
-	return klass->ip4_route_add (self, route);
+	return klass->ip_route_add (self, flags, AF_INET, (const NMPlatformIPRoute *) route);
 }
 
 gboolean
-nm_platform_ip6_route_add (NMPlatform *self, const NMPlatformIP6Route *route)
+nm_platform_ip6_route_add (NMPlatform *self,
+                           NMPNlmFlags flags,
+                           const NMPlatformIP6Route *route)
 {
+	char sbuf[sizeof (_nm_utils_to_string_buffer)];
+
 	_CHECK_SELF (self, klass, FALSE);
 
 	g_return_val_if_fail (route, FALSE);
 	g_return_val_if_fail (route->plen <= 128, FALSE);
 
-	_LOGD ("route: adding or updating IPv6 route: %s", nm_platform_ip6_route_to_string (route, NULL, 0));
+	_LOGD ("route: %-10s IPv6 route: %s",
+	       _nmp_nlm_flag_to_string (flags),
+	       nm_platform_ip6_route_to_string (route, sbuf, sizeof (sbuf)));
 
-	return klass->ip6_route_add (self, route);
+	return klass->ip_route_add (self, flags, AF_INET6, (const NMPlatformIPRoute *) route);
 }
 
 gboolean
@@ -3467,7 +3474,7 @@ nm_platform_ip_route_delete (NMPlatform *self,
 	nm_assert (NM_IN_SET (NMP_OBJECT_GET_TYPE (obj), NMP_OBJECT_TYPE_IP4_ROUTE,
 	                                                 NMP_OBJECT_TYPE_IP6_ROUTE));
 
-	_LOGD ("route: deleting IPv%c route %s",
+	_LOGD ("route: delete     IPv%c route %s",
 	       NMP_OBJECT_GET_TYPE (obj) == NMP_OBJECT_TYPE_IP4_ROUTE ? '4' : '6',
 	       nmp_object_to_string (obj, NMP_OBJECT_TO_STRING_PUBLIC, NULL, 0));
 
@@ -5177,7 +5184,11 @@ nm_platform_netns_push (NMPlatform *self, NMPNetns **netns)
 /*****************************************************************************/
 
 static gboolean
-_vtr_v4_route_add (NMPlatform *self, int ifindex, const NMPlatformIPXRoute *route, gint64 metric)
+_vtr_v4_route_add (NMPlatform *self,
+                   NMPNlmFlags flags,
+                   const NMPlatformIPXRoute *route,
+                   int ifindex,
+                   gint64 metric)
 {
 	NMPlatformIP4Route rt = route->r4;
 
@@ -5186,11 +5197,15 @@ _vtr_v4_route_add (NMPlatform *self, int ifindex, const NMPlatformIPXRoute *rout
 	if (metric >= 0)
 		rt.metric = metric;
 
-	return nm_platform_ip4_route_add (self, &rt);
+	return nm_platform_ip4_route_add (self, flags, &rt);
 }
 
 static gboolean
-_vtr_v6_route_add (NMPlatform *self, int ifindex, const NMPlatformIPXRoute *route, gint64 metric)
+_vtr_v6_route_add (NMPlatform *self,
+                   NMPNlmFlags flags,
+                   const NMPlatformIPXRoute *route,
+                   int ifindex,
+                   gint64 metric)
 {
 	NMPlatformIP6Route rt = route->r6;
 
@@ -5199,7 +5214,7 @@ _vtr_v6_route_add (NMPlatform *self, int ifindex, const NMPlatformIPXRoute *rout
 	if (metric >= 0)
 		rt.metric = metric;
 
-	return nm_platform_ip6_route_add (self, &rt);
+	return nm_platform_ip6_route_add (self, flags, &rt);
 }
 
 static guint32
diff --git a/src/platform/nm-platform.h b/src/platform/nm-platform.h
index 9f04d08917..a40d33f43d 100644
--- a/src/platform/nm-platform.h
+++ b/src/platform/nm-platform.h
@@ -74,6 +74,25 @@ struct udev_device;
 #define NM_GRE_KEY      0x2000
 
 typedef enum {
+	/* use our own platform enum for the nlmsg-flags. Otherwise, we'd have
+	 * to include <linux/netlink.h> */
+	NMP_NLM_FLAG_F_REPLACE      = 0x100, /* NLM_F_REPLACE, Override existing */
+	NMP_NLM_FLAG_F_EXCL         = 0x200, /* NLM_F_EXCL, Do not touch, if it exists */
+	NMP_NLM_FLAG_F_CREATE       = 0x400, /* NLM_F_CREATE, Create, if it does not exist */
+	NMP_NLM_FLAG_F_APPEND       = 0x800, /* NLM_F_APPEND, Add to end of list */
+
+	/* the following aliases correspond to iproute2's `ip route CMD` for
+	 * RTM_NEWROUTE, with CMD being one of add, change, replace, prepend,
+	 * append and test. */
+	NMP_NLM_FLAG_ADD            = NMP_NLM_FLAG_F_CREATE                          | NMP_NLM_FLAG_F_EXCL,
+	NMP_NLM_FLAG_CHANGE         =                         NMP_NLM_FLAG_F_REPLACE,
+	NMP_NLM_FLAG_REPLACE        = NMP_NLM_FLAG_F_CREATE | NMP_NLM_FLAG_F_REPLACE,
+	NMP_NLM_FLAG_PREPEND        = NMP_NLM_FLAG_F_CREATE,
+	NMP_NLM_FLAG_APPEND         = NMP_NLM_FLAG_F_CREATE                                                | NMP_NLM_FLAG_F_APPEND,
+	NMP_NLM_FLAG_TEST           =                                                  NMP_NLM_FLAG_F_EXCL,
+} NMPNlmFlags;
+
+typedef enum {
 	/* compare fields which kernel considers as similar routes.
 	 * It is a looser comparisong then NM_PLATFORM_IP_ROUTE_CMP_TYPE_ID
 	 * and means that `ip route add` would fail to add two routes
@@ -489,7 +508,11 @@ typedef struct {
 	gsize sizeof_route;
 	int (*route_cmp) (const NMPlatformIPXRoute *a, const NMPlatformIPXRoute *b, NMPlatformIPRouteCmpType cmp_type);
 	const char *(*route_to_string) (const NMPlatformIPXRoute *route, char *buf, gsize len);
-	gboolean (*route_add) (NMPlatform *self, int ifindex, const NMPlatformIPXRoute *route, gint64 metric);
+	gboolean (*route_add) (NMPlatform *self,
+	                       NMPNlmFlags flags,
+	                       const NMPlatformIPXRoute *route,
+	                       int ifindex,
+	                       gint64 metric);
 	guint32 (*metric_normalize) (guint32 metric);
 } NMPlatformVTableRoute;
 
@@ -763,8 +786,10 @@ typedef struct {
 	gboolean (*ip4_address_delete) (NMPlatform *, int ifindex, in_addr_t address, guint8 plen, in_addr_t peer_address);
 	gboolean (*ip6_address_delete) (NMPlatform *, int ifindex, struct in6_addr address, guint8 plen);
 
-	gboolean (*ip4_route_add) (NMPlatform *, const NMPlatformIP4Route *route);
-	gboolean (*ip6_route_add) (NMPlatform *, const NMPlatformIP6Route *route);
+	gboolean (*ip_route_add) (NMPlatform *,
+	                          NMPNlmFlags flags,
+	                          int addr_family,
+	                          const NMPlatformIPRoute *route);
 	gboolean (*ip_route_delete) (NMPlatform *, const NMPObject *obj);
 
 	gboolean (*check_support_kernel_extended_ifa_flags) (NMPlatform *);
@@ -1077,8 +1102,10 @@ gboolean nm_platform_address_flush (NMPlatform *self, int ifindex);
 
 const NMPlatformIP4Route *nm_platform_ip4_route_get (NMPlatform *self, int ifindex, in_addr_t network, guint8 plen, guint32 metric);
 const NMPlatformIP6Route *nm_platform_ip6_route_get (NMPlatform *self, int ifindex, struct in6_addr network, guint8 plen, guint32 metric);
-gboolean nm_platform_ip4_route_add (NMPlatform *self, const NMPlatformIP4Route *route);
-gboolean nm_platform_ip6_route_add (NMPlatform *self, const NMPlatformIP6Route *route);
+
+gboolean nm_platform_ip4_route_add (NMPlatform *self, NMPNlmFlags flags, const NMPlatformIP4Route *route);
+gboolean nm_platform_ip6_route_add (NMPlatform *self, NMPNlmFlags flags, const NMPlatformIP6Route *route);
+
 gboolean nm_platform_ip_route_delete (NMPlatform *self, const NMPObject *route);
 
 const char *nm_platform_link_to_string (const NMPlatformLink *link, char *buf, gsize len);
diff --git a/src/platform/tests/test-common.c b/src/platform/tests/test-common.c
index 51234cf17a..feef869f4f 100644
--- a/src/platform/tests/test-common.c
+++ b/src/platform/tests/test-common.c
@@ -903,7 +903,7 @@ void nmtstp_ip4_route_add (NMPlatform *platform,
 	route.metric = metric;
 	route.mss = mss;
 
-	g_assert (nm_platform_ip4_route_add (platform, &route));
+	g_assert (nm_platform_ip4_route_add (platform, NMP_NLM_FLAG_REPLACE, &route));
 }
 
 void nmtstp_ip6_route_add (NMPlatform *platform,
@@ -927,7 +927,7 @@ void nmtstp_ip6_route_add (NMPlatform *platform,
 	route.metric = metric;
 	route.mss = mss;
 
-	g_assert (nm_platform_ip6_route_add (platform, &route));
+	g_assert (nm_platform_ip6_route_add (platform, NMP_NLM_FLAG_REPLACE, &route));
 }
 
 /*****************************************************************************/
diff --git a/src/platform/tests/test-route.c b/src/platform/tests/test-route.c
index ac3aa80b8b..94be799bb5 100644
--- a/src/platform/tests/test-route.c
+++ b/src/platform/tests/test-route.c
@@ -432,7 +432,7 @@ test_ip4_route_options (void)
 	route.mtu = 1350;
 	route.lock_cwnd = TRUE;
 
-	g_assert (nm_platform_ip4_route_add (NM_PLATFORM_GET, &route));
+	g_assert (nm_platform_ip4_route_add (NM_PLATFORM_GET, NMP_NLM_FLAG_REPLACE, &route));
 
 	/* Test route listing */
 	routes = nmtstp_ip4_route_get_all (NM_PLATFORM_GET, ifindex);
@@ -532,7 +532,7 @@ test_ip6_route_options (gconstpointer test_data)
 	_wait_for_ipv6_addr_non_tentative (NM_PLATFORM_GET, 400, IFINDEX, addr_n, addr_in6);
 
 	for (i = 0; i < rts_n; i++)
-		g_assert (nm_platform_ip6_route_add (NM_PLATFORM_GET, &rts_add[i]));
+		g_assert (nm_platform_ip6_route_add (NM_PLATFORM_GET, NMP_NLM_FLAG_REPLACE, &rts_add[i]));
 
 	routes = nmtstp_ip6_route_get_all (NM_PLATFORM_GET, IFINDEX);
 	switch (TEST_IDX) {
diff --git a/src/tests/test-route-manager.c b/src/tests/test-route-manager.c
index e6b72ac87e..e7d0321a1e 100644
--- a/src/tests/test-route-manager.c
+++ b/src/tests/test-route-manager.c
@@ -857,7 +857,7 @@ test_ip4_full_sync (test_fixture *fixture, gconstpointer user_data)
 	_assert_route_check (vtable, TRUE,  (const NMPlatformIPXRoute *) &r02);
 	_assert_route_check (vtable, FALSE, (const NMPlatformIPXRoute *) &r03);
 
-	vtable->route_add (NM_PLATFORM_GET, 0, (const NMPlatformIPXRoute *) &r03, -1);
+	vtable->route_add (NM_PLATFORM_GET, NMP_NLM_FLAG_REPLACE, (const NMPlatformIPXRoute *) &r03, 0, -1);
 
 	_assert_route_check (vtable, TRUE,  (const NMPlatformIPXRoute *) &r01);
 	_assert_route_check (vtable, TRUE,  (const NMPlatformIPXRoute *) &r02);