core: don't track route MSS in ip-config

The MSS is only set for VPN connections (by merging it in the respective
NMIP4Config/NMIP6Config).

It is also only used when setting the MSS of the default route.

Don't track that property in NMIP4Config/NMIP6Config, instead, set the
mss of the route directly in nm_vpn_connection_ip4_config_get() and
nm_vpn_connection_ip6_config_get().

There is a potential change in behavior here: NMDevice also consisdered
the MSS for the default route, but that would only be set if the MSS
gets merged from an vpn-ip-config. Which at most is the case for
iterface-less VPN types (libreswan). But even in that case, it doesn't
seem right to me to use the VPN's MSS for the device's default-route.

7 files changed, 8 insertions, 92 deletions

diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c
index 67f87adb7f..8165c3fcf0 100644
--- a/src/devices/nm-device.c
+++ b/src/devices/nm-device.c
@@ -5868,7 +5868,6 @@ ip4_config_merge_and_apply (NMDevice *self,
 	default_route.gateway = gateway;
 	default_route.table_coerced = nm_platform_route_table_coerce (nm_device_get_route_table (self, AF_INET, TRUE));
 	default_route.metric = route_metric_with_penalty (self, default_route_metric);
-	default_route.mss = nm_ip4_config_get_mss (composite);
 	nm_clear_nmp_object (&priv->default_route4);
 	nm_ip4_config_add_route (composite, &default_route, &priv->default_route4);
 
@@ -6609,7 +6608,6 @@ ip6_config_merge_and_apply (NMDevice *self,
 	default_route.gateway = *gateway;
 	default_route.table_coerced = nm_platform_route_table_coerce (nm_device_get_route_table (self, AF_INET6, TRUE));
 	default_route.metric = route_metric_with_penalty (self, default_route_metric);
-	default_route.mss = nm_ip6_config_get_mss (composite);
 	nm_clear_nmp_object (&priv->default_route6);
 	nm_ip6_config_add_route (composite, &default_route, &priv->default_route6);
 
diff --git a/src/nm-ip4-config.c b/src/nm-ip4-config.c
index fe32358081..101b3b0fbc 100644
--- a/src/nm-ip4-config.c
+++ b/src/nm-ip4-config.c
@@ -291,7 +291,6 @@ typedef struct {
 	bool metered:1;
 	bool has_gateway:1;
 	guint32 gateway;
-	guint32 mss;
 	guint32 mtu;
 	int ifindex;
 	NMIPConfigSource mtu_source;
@@ -1141,10 +1140,6 @@ nm_ip4_config_merge (NMIP4Config *dst, const NMIP4Config *src, NMIPConfigMergeFl
 			nm_ip4_config_add_dns_option (dst, nm_ip4_config_get_dns_option (src, i));
 	}
 
-	/* MSS */
-	if (nm_ip4_config_get_mss (src))
-		nm_ip4_config_set_mss (dst, nm_ip4_config_get_mss (src));
-
 	/* MTU */
 	if (   src_priv->mtu_source > dst_priv->mtu_source
 	    || (   src_priv->mtu_source == dst_priv->mtu_source
@@ -1372,10 +1367,6 @@ nm_ip4_config_subtract (NMIP4Config *dst, const NMIP4Config *src)
 			nm_ip4_config_del_dns_option (dst, idx);
 	}
 
-	/* MSS */
-	if (nm_ip4_config_get_mss (src) == nm_ip4_config_get_mss (dst))
-		nm_ip4_config_set_mss (dst, 0);
-
 	/* MTU */
 	if (   nm_ip4_config_get_mtu (src) == nm_ip4_config_get_mtu (dst)
 	    && nm_ip4_config_get_mtu_source (src) == nm_ip4_config_get_mtu_source (dst))
@@ -1733,12 +1724,6 @@ nm_ip4_config_replace (NMIP4Config *dst, const NMIP4Config *src, gboolean *relev
 		has_minor_changes = TRUE;
 	}
 
-	/* mss */
-	if (src_priv->mss != dst_priv->mss) {
-		nm_ip4_config_set_mss (dst, src_priv->mss);
-		has_minor_changes = TRUE;
-	}
-
 	/* nis */
 	num = nm_ip4_config_get_num_nis_servers (src);
 	are_equal = num == nm_ip4_config_get_num_nis_servers (dst);
@@ -1863,7 +1848,6 @@ nm_ip4_config_dump (const NMIP4Config *self, const char *detail)
 
 	g_message (" dnspri: %d", nm_ip4_config_get_dns_priority (self));
 
-	g_message ("    mss: %"G_GUINT32_FORMAT, nm_ip4_config_get_mss (self));
 	g_message ("    mtu: %"G_GUINT32_FORMAT" (source: %d)", nm_ip4_config_get_mtu (self), (int) nm_ip4_config_get_mtu_source (self));
 
 	/* NIS */
@@ -2518,24 +2502,6 @@ nm_ip4_config_get_dns_priority (const NMIP4Config *self)
 /*****************************************************************************/
 
 void
-nm_ip4_config_set_mss (NMIP4Config *self, guint32 mss)
-{
-	NMIP4ConfigPrivate *priv = NM_IP4_CONFIG_GET_PRIVATE (self);
-
-	priv->mss = mss;
-}
-
-guint32
-nm_ip4_config_get_mss (const NMIP4Config *self)
-{
-	const NMIP4ConfigPrivate *priv = NM_IP4_CONFIG_GET_PRIVATE (self);
-
-	return priv->mss;
-}
-
-/*****************************************************************************/
-
-void
 nm_ip4_config_reset_nis_servers (NMIP4Config *self)
 {
 	NMIP4ConfigPrivate *priv = NM_IP4_CONFIG_GET_PRIVATE (self);
diff --git a/src/nm-ip4-config.h b/src/nm-ip4-config.h
index 230cee6a1b..429c0752fe 100644
--- a/src/nm-ip4-config.h
+++ b/src/nm-ip4-config.h
@@ -233,9 +233,6 @@ const char * nm_ip4_config_get_dns_option (const NMIP4Config *self, guint i);
 void nm_ip4_config_set_dns_priority (NMIP4Config *self, gint priority);
 gint nm_ip4_config_get_dns_priority (const NMIP4Config *self);
 
-void nm_ip4_config_set_mss (NMIP4Config *self, guint32 mss);
-guint32 nm_ip4_config_get_mss (const NMIP4Config *self);
-
 void nm_ip4_config_reset_nis_servers (NMIP4Config *self);
 void nm_ip4_config_add_nis_server (NMIP4Config *self, guint32 nis);
 void nm_ip4_config_del_nis_server (NMIP4Config *self, guint i);
diff --git a/src/nm-ip6-config.c b/src/nm-ip6-config.c
index 480465e5b9..6516b8b840 100644
--- a/src/nm-ip6-config.c
+++ b/src/nm-ip6-config.c
@@ -59,7 +59,6 @@ _route_valid (const NMPlatformIP6Route *r)
 
 typedef struct {
 	bool never_default:1;
-	guint32 mss;
 	int ifindex;
 	int dns_priority;
 	NMSettingIP6ConfigPrivacy privacy;
@@ -940,9 +939,6 @@ nm_ip6_config_merge (NMIP6Config *dst, const NMIP6Config *src, NMIPConfigMergeFl
 			nm_ip6_config_add_dns_option (dst, nm_ip6_config_get_dns_option (src, i));
 	}
 
-	if (nm_ip6_config_get_mss (src))
-		nm_ip6_config_set_mss (dst, nm_ip6_config_get_mss (src));
-
 	/* DNS priority */
 	if (nm_ip6_config_get_dns_priority (src))
 		nm_ip6_config_set_dns_priority (dst, nm_ip6_config_get_dns_priority (src));
@@ -1135,9 +1131,6 @@ nm_ip6_config_subtract (NMIP6Config *dst, const NMIP6Config *src)
 			nm_ip6_config_del_dns_option (dst, idx);
 	}
 
-	if (nm_ip6_config_get_mss (src) == nm_ip6_config_get_mss (dst))
-		nm_ip6_config_set_mss (dst, 0);
-
 	/* DNS priority */
 	if (nm_ip6_config_get_dns_priority (src) == nm_ip6_config_get_dns_priority (dst))
 		nm_ip6_config_set_dns_priority (dst, 0);
@@ -1468,12 +1461,6 @@ nm_ip6_config_replace (NMIP6Config *dst, const NMIP6Config *src, gboolean *relev
 		has_relevant_changes = TRUE;
 	}
 
-	/* mss */
-	if (src_priv->mss != dst_priv->mss) {
-		nm_ip6_config_set_mss (dst, src_priv->mss);
-		has_minor_changes = TRUE;
-	}
-
 	/* DNS priority */
 	if (src_priv->dns_priority != dst_priv->dns_priority) {
 		nm_ip6_config_set_dns_priority (dst, src_priv->dns_priority);
@@ -1550,7 +1537,6 @@ nm_ip6_config_dump (const NMIP6Config *self, const char *detail)
 
 	g_message (" dnspri: %d", nm_ip6_config_get_dns_priority (self));
 
-	g_message ("    mss: %"G_GUINT32_FORMAT, nm_ip6_config_get_mss (self));
 	g_message (" n-dflt: %d", nm_ip6_config_get_never_default (self));
 }
 
@@ -2338,24 +2324,6 @@ nm_ip6_config_get_dns_priority (const NMIP6Config *self)
 
 /*****************************************************************************/
 
-void
-nm_ip6_config_set_mss (NMIP6Config *self, guint32 mss)
-{
-	NMIP6ConfigPrivate *priv = NM_IP6_CONFIG_GET_PRIVATE (self);
-
-	priv->mss = mss;
-}
-
-guint32
-nm_ip6_config_get_mss (const NMIP6Config *self)
-{
-	const NMIP6ConfigPrivate *priv = NM_IP6_CONFIG_GET_PRIVATE (self);
-
-	return priv->mss;
-}
-
-/*****************************************************************************/
-
 const NMPObject *
 nm_ip6_config_nmpobj_lookup (const NMIP6Config *self, const NMPObject *needle)
 {
diff --git a/src/nm-ip6-config.h b/src/nm-ip6-config.h
index 8b738331f7..3555d53eb5 100644
--- a/src/nm-ip6-config.h
+++ b/src/nm-ip6-config.h
@@ -194,9 +194,6 @@ const char * nm_ip6_config_get_dns_option (const NMIP6Config *self, guint i);
 void nm_ip6_config_set_dns_priority (NMIP6Config *self, gint priority);
 gint nm_ip6_config_get_dns_priority (const NMIP6Config *self);
 
-void nm_ip6_config_set_mss (NMIP6Config *self, guint32 mss);
-guint32 nm_ip6_config_get_mss (const NMIP6Config *self);
-
 const NMPObject *nm_ip6_config_nmpobj_lookup (const NMIP6Config *self,
                                               const NMPObject *needle);
 gboolean nm_ip6_config_nmpobj_remove (NMIP6Config *self,
diff --git a/src/tests/test-ip4-config.c b/src/tests/test-ip4-config.c
index 8c6cd8d15c..c2a1c006c5 100644
--- a/src/tests/test-ip4-config.c
+++ b/src/tests/test-ip4-config.c
@@ -84,7 +84,6 @@ test_subtract (void)
 	const char *expected_search = "somewhere.com";
 	guint32 expected_nis = nmtst_inet4_from_string ("1.2.3.13");
 	guint32 expected_wins = nmtst_inet4_from_string ("2.3.4.5");
-	guint32 expected_mss = 1400;
 	guint32 expected_mtu = 1492;
 
 	src = build_test_config ();
@@ -105,7 +104,6 @@ test_subtract (void)
 	nm_ip4_config_add_nis_server (dst, expected_nis);
 	nm_ip4_config_add_wins (dst, expected_wins);
 
-	nm_ip4_config_set_mss (dst, expected_mss);
 	nm_ip4_config_set_mtu (dst, expected_mtu, NM_IP_CONFIG_SOURCE_UNKNOWN);
 
 	nm_ip4_config_subtract (dst, src);
@@ -142,7 +140,6 @@ test_subtract (void)
 	g_assert_cmpuint (nm_ip4_config_get_num_wins (dst), ==, 1);
 	g_assert_cmpuint (nm_ip4_config_get_wins (dst, 0), ==, expected_wins);
 
-	g_assert_cmpuint (nm_ip4_config_get_mss (dst), ==, expected_mss);
 	g_assert_cmpuint (nm_ip4_config_get_mtu (dst), ==, expected_mtu);
 
 	g_object_unref (src);
@@ -267,12 +264,10 @@ test_add_route_with_source (void)
 }
 
 static void
-test_merge_subtract_mss_mtu (void)
+test_merge_subtract_mtu (void)
 {
 	NMIP4Config *cfg1, *cfg2, *cfg3;
-	guint32 expected_mss2 = 1400;
 	guint32 expected_mtu2 = 1492;
-	guint32 expected_mss3 = 555;
 	guint32 expected_mtu3 = 666;
 
 	cfg1 = build_test_config ();
@@ -280,24 +275,19 @@ test_merge_subtract_mss_mtu (void)
 	cfg3 = build_test_config ();
 
 	/* add MSS, MTU to configs to test them */
-	nm_ip4_config_set_mss (cfg2, expected_mss2);
 	nm_ip4_config_set_mtu (cfg2, expected_mtu2, NM_IP_CONFIG_SOURCE_UNKNOWN);
-	nm_ip4_config_set_mss (cfg3, expected_mss3);
 	nm_ip4_config_set_mtu (cfg3, expected_mtu3, NM_IP_CONFIG_SOURCE_UNKNOWN);
 
 	nm_ip4_config_merge (cfg1, cfg2, NM_IP_CONFIG_MERGE_DEFAULT);
 	/* ensure MSS and MTU are in cfg1 */
-	g_assert_cmpuint (nm_ip4_config_get_mss (cfg1), ==, expected_mss2);
 	g_assert_cmpuint (nm_ip4_config_get_mtu (cfg1), ==, expected_mtu2);
 
 	nm_ip4_config_merge (cfg1, cfg3, NM_IP_CONFIG_MERGE_DEFAULT);
 	/* ensure again the MSS and MTU in cfg1 got overridden */
-	g_assert_cmpuint (nm_ip4_config_get_mss (cfg1), ==, expected_mss3);
 	g_assert_cmpuint (nm_ip4_config_get_mtu (cfg1), ==, expected_mtu3);
 
 	nm_ip4_config_subtract (cfg1, cfg3);
 	/* ensure MSS and MTU are zero in cfg1 */
-	g_assert_cmpuint (nm_ip4_config_get_mss (cfg1), ==, 0);
 	g_assert_cmpuint (nm_ip4_config_get_mtu (cfg1), ==, 0);
 
 	g_object_unref (cfg1);
@@ -339,7 +329,7 @@ main (int argc, char **argv)
 	g_test_add_func ("/ip4-config/compare-with-source", test_compare_with_source);
 	g_test_add_func ("/ip4-config/add-address-with-source", test_add_address_with_source);
 	g_test_add_func ("/ip4-config/add-route-with-source", test_add_route_with_source);
-	g_test_add_func ("/ip4-config/merge-subtract-mss-mtu", test_merge_subtract_mss_mtu);
+	g_test_add_func ("/ip4-config/merge-subtract-mtu", test_merge_subtract_mtu);
 	g_test_add_func ("/ip4-config/strip-search-trailing-dot", test_strip_search_trailing_dot);
 
 	return g_test_run ();
diff --git a/src/vpn/nm-vpn-connection.c b/src/vpn/nm-vpn-connection.c
index 893033e431..e9a2bd919f 100644
--- a/src/vpn/nm-vpn-connection.c
+++ b/src/vpn/nm-vpn-connection.c
@@ -1010,7 +1010,6 @@ print_vpn_config (NMVpnConnection *self)
 		_LOGI ("Data:   Internal Address: %s", nm_utils_inet4_ntop (address4->address, NULL));
 		_LOGI ("Data:   Internal Prefix: %d", address4->plen);
 		_LOGI ("Data:   Internal Point-to-Point Address: %s", nm_utils_inet4_ntop (address4->peer_address, NULL));
-		_LOGI ("Data:   Maximum Segment Size (MSS): %d", nm_ip4_config_get_mss (priv->ip4_config));
 
 		nm_ip_config_iter_ip4_route_for_each (&ipconf_iter, priv->ip4_config, &route) {
 			_LOGI ("Data:   Static Route: %s/%d   Next Hop: %s",
@@ -1048,7 +1047,6 @@ print_vpn_config (NMVpnConnection *self)
 		_LOGI ("Data:   Internal Address: %s", nm_utils_inet6_ntop (&address6->address, NULL));
 		_LOGI ("Data:   Internal Prefix: %d", address6->plen);
 		_LOGI ("Data:   Internal Point-to-Point Address: %s", nm_utils_inet6_ntop (&address6->peer_address, NULL));
-		_LOGI ("Data:   Maximum Segment Size (MSS): %d", nm_ip6_config_get_mss (priv->ip6_config));
 
 		nm_ip_config_iter_ip6_route_for_each (&ipconf_iter, priv->ip6_config, &route) {
 			_LOGI ("Data:   Static Route: %s/%d   Next Hop: %s",
@@ -1480,6 +1478,7 @@ nm_vpn_connection_ip4_config_get (NMVpnConnection *self, GVariant *dict)
 	GVariant *v;
 	gboolean b;
 	int ip_ifindex;
+	guint32 mss = 0;
 
 	g_return_if_fail (dict && g_variant_is_of_type (dict, G_VARIANT_TYPE_VARDICT));
 
@@ -1563,7 +1562,7 @@ nm_vpn_connection_ip4_config_get (NMVpnConnection *self, GVariant *dict)
 	}
 
 	if (g_variant_lookup (dict, NM_VPN_PLUGIN_IP4_CONFIG_MSS, "u", &u32))
-		nm_ip4_config_set_mss (config, u32);
+		mss = u32;
 
 	if (g_variant_lookup (dict, NM_VPN_PLUGIN_IP4_CONFIG_DOMAIN, "&s", &str))
 		nm_ip4_config_add_domain (config, str);
@@ -1641,7 +1640,7 @@ nm_vpn_connection_ip4_config_get (NMVpnConnection *self, GVariant *dict)
 			.gateway   = nm_ip4_config_get_gateway (config),
 			.table_coerced = nm_platform_route_table_coerce (route_table),
 			.metric    = route_metric,
-			.mss       = nm_ip4_config_get_mss (config),
+			.mss       = mss,
 		};
 
 		nm_ip4_config_add_route (config, &r, NULL);
@@ -1679,6 +1678,7 @@ nm_vpn_connection_ip6_config_get (NMVpnConnection *self, GVariant *dict)
 	GVariant *v;
 	gboolean b;
 	int ip_ifindex;
+	guint32 mss = 0;
 
 	g_return_if_fail (dict && g_variant_is_of_type (dict, G_VARIANT_TYPE_VARDICT));
 
@@ -1752,7 +1752,7 @@ nm_vpn_connection_ip6_config_get (NMVpnConnection *self, GVariant *dict)
 	}
 
 	if (g_variant_lookup (dict, NM_VPN_PLUGIN_IP6_CONFIG_MSS, "u", &u32))
-		nm_ip6_config_set_mss (config, u32);
+		mss = u32;
 
 	if (g_variant_lookup (dict, NM_VPN_PLUGIN_IP6_CONFIG_DOMAIN, "&s", &str))
 		nm_ip6_config_add_domain (config, str);
@@ -1827,7 +1827,7 @@ next:
 			.gateway   = *(nm_ip6_config_get_gateway (config) ?: &in6addr_any),
 			.table_coerced = nm_platform_route_table_coerce (route_table),
 			.metric    = route_metric,
-			.mss       = nm_ip6_config_get_mss (config),
+			.mss       = mss,
 		};
 
 		nm_ip6_config_add_route (config, &r, NULL);