]> git.ipfire.org Git - thirdparty/systemd.git/blobdiff - src/network/networkd-link.c
network: ignore requested ipv6 routing policy rule when ipv6 is disabled by sysctl
[thirdparty/systemd.git] / src / network / networkd-link.c
index c5857da8fc456b47020c0f5778363b416cd6a786..0c243508a4314ef3f01c1196c13fe748a4f6f280 100644 (file)
@@ -2,7 +2,6 @@
 
 #include <netinet/in.h>
 #include <linux/if.h>
-#include <linux/can/netlink.h>
 #include <unistd.h>
 
 #include "alloc-util.h"
 #include "fd-util.h"
 #include "fileio.h"
 #include "missing_network.h"
+#include "netdev/bond.h"
+#include "netdev/bridge.h"
+#include "netdev/ipvlan.h"
 #include "netdev/vrf.h"
 #include "netlink-util.h"
 #include "network-internal.h"
+#include "networkd-can.h"
 #include "networkd-ipv6-proxy-ndp.h"
 #include "networkd-lldp-tx.h"
 #include "networkd-manager.h"
@@ -74,6 +77,9 @@ static bool link_dhcp6_enabled(Link *link) {
         if (link->network->bond)
                 return false;
 
+        if (STRPTR_IN_SET(link->kind, "can", "vcan", "vxcan"))
+                return false;
+
         if (manager_sysctl_ipv6_enabled(link->manager) == 0)
                 return false;
 
@@ -92,6 +98,9 @@ static bool link_dhcp4_enabled(Link *link) {
         if (link->network->bond)
                 return false;
 
+        if (STRPTR_IN_SET(link->kind, "can", "vcan", "vxcan"))
+                return false;
+
         return link->network->dhcp & ADDRESS_FAMILY_IPV4;
 }
 
@@ -107,11 +116,15 @@ static bool link_dhcp4_server_enabled(Link *link) {
         if (link->network->bond)
                 return false;
 
+        if (STRPTR_IN_SET(link->kind, "can", "vcan", "vxcan"))
+                return false;
+
         return link->network->dhcp_server;
 }
 
-bool link_ipv4ll_enabled(Link *link) {
+bool link_ipv4ll_enabled(Link *link, AddressFamilyBoolean mask) {
         assert(link);
+        assert((mask & ~(ADDRESS_FAMILY_IPV4 | ADDRESS_FAMILY_FALLBACK_IPV4)) == 0);
 
         if (link->flags & IFF_LOOPBACK)
                 return false;
@@ -119,31 +132,20 @@ bool link_ipv4ll_enabled(Link *link) {
         if (!link->network)
                 return false;
 
-        if (STRPTR_IN_SET(link->kind, "vrf", "wireguard"))
-                return false;
-
-        if (link->network->bond)
-                return false;
-
-        return link->network->link_local & ADDRESS_FAMILY_IPV4;
-}
-
-bool link_ipv4ll_fallback_enabled(Link *link) {
-        assert(link);
-
-        if (link->flags & IFF_LOOPBACK)
+        if (STRPTR_IN_SET(link->kind, "vrf", "wireguard", "ipip", "gre", "ip6gre", "ip6tnl", "sit", "vti", "vti6", "can", "vcan", "vxcan", "nlmon"))
                 return false;
 
-        if (!link->network)
+        /* L3 or L3S mode do not support ARP. */
+        if (IN_SET(link_get_ipvlan_mode(link), NETDEV_IPVLAN_MODE_L3, NETDEV_IPVLAN_MODE_L3S))
                 return false;
 
-        if (STRPTR_IN_SET(link->kind, "vrf", "wireguard"))
+        if (link->network->bond)
                 return false;
 
         if (link->network->bond)
                 return false;
 
-        return link->network->link_local & ADDRESS_FAMILY_FALLBACK_IPV4;
+        return link->network->link_local & mask;
 }
 
 static bool link_ipv6ll_enabled(Link *link) {
@@ -158,7 +160,7 @@ static bool link_ipv6ll_enabled(Link *link) {
         if (!link->network)
                 return false;
 
-        if (STRPTR_IN_SET(link->kind, "vrf", "wireguard"))
+        if (STRPTR_IN_SET(link->kind, "vrf", "wireguard", "ipip", "gre", "sit", "vti", "can", "vcan", "vxcan", "nlmon"))
                 return false;
 
         if (link->network->bond)
@@ -182,6 +184,9 @@ static bool link_ipv6_enabled(Link *link) {
         if (manager_sysctl_ipv6_enabled(link->manager) == 0)
                 return false;
 
+        if (STRPTR_IN_SET(link->kind, "can", "vcan", "vxcan"))
+                return false;
+
         /* DHCPv6 client will not be started if no IPv6 link-local address is configured. */
         return link_ipv6ll_enabled(link) || network_has_static_ipv6_addresses(link->network);
 }
@@ -314,16 +319,14 @@ static bool link_is_enslaved(Link *link) {
                 /* Even if the link is not managed by networkd, honor IFF_SLAVE flag. */
                 return true;
 
-        if (!link->enslaved_raw)
-                return false;
-
         if (!link->network)
                 return false;
 
-        if (link->network->bridge)
-                /* TODO: support the case when link is not managed by networkd. */
+        if (link->master_ifindex > 0 && link->network->bridge)
                 return true;
 
+        /* TODO: add conditions for other netdevs. */
+
         return false;
 }
 
@@ -415,7 +418,7 @@ void link_update_operstate(Link *link, bool also_update_master) {
                 ? ((old & flag) ? (" -" string) : (" +" string)) \
                 : "")
 
-static int link_update_flags(Link *link, sd_netlink_message *m) {
+static int link_update_flags(Link *link, sd_netlink_message *m, bool force_update_operstate) {
         unsigned flags, unknown_flags_added, unknown_flags_removed, unknown_flags;
         uint8_t operstate;
         int r;
@@ -432,7 +435,7 @@ static int link_update_flags(Link *link, sd_netlink_message *m) {
                    the state was unchanged */
                 operstate = link->kernel_operstate;
 
-        if ((link->flags == flags) && (link->kernel_operstate == operstate))
+        if (!force_update_operstate && (link->flags == flags) && (link->kernel_operstate == operstate))
                 return 0;
 
         if (link->flags != flags) {
@@ -575,7 +578,7 @@ static int link_new(Manager *manager, sd_netlink_message *message, Link **ret) {
         if (r < 0)
                 return r;
 
-        r = link_update_flags(link, message);
+        r = link_update_flags(link, message, false);
         if (r < 0)
                 return r;
 
@@ -654,7 +657,7 @@ int link_get(Manager *m, int ifindex, Link **ret) {
         return 0;
 }
 
-static void link_set_state(Link *link, LinkState state) {
+void link_set_state(Link *link, LinkState state) {
         assert(link);
 
         if (link->state == state)
@@ -672,21 +675,22 @@ static void link_set_state(Link *link, LinkState state) {
 static void link_enter_unmanaged(Link *link) {
         assert(link);
 
-        log_link_debug(link, "Unmanaged");
-
         link_set_state(link, LINK_STATE_UNMANAGED);
 
         link_dirty(link);
 }
 
-int link_stop_clients(Link *link) {
+int link_stop_clients(Link *link, bool may_keep_dhcp) {
         int r = 0, k;
 
         assert(link);
         assert(link->manager);
         assert(link->manager->event);
 
-        if (link->dhcp_client) {
+        dhcp4_release_old_lease(link);
+
+        if (link->dhcp_client && (!may_keep_dhcp || !link->network ||
+                                  !FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_DHCP_ON_STOP))) {
                 k = sd_dhcp_client_stop(link->dhcp_client);
                 if (k < 0)
                         r = log_link_warning_errno(link, k, "Could not stop DHCPv4 client: %m");
@@ -730,7 +734,7 @@ void link_enter_failed(Link *link) {
 
         link_set_state(link, LINK_STATE_FAILED);
 
-        link_stop_clients(link);
+        link_stop_clients(link, false);
 
         link_dirty(link);
 }
@@ -828,14 +832,14 @@ static int link_request_set_routing_policy_rule(Link *link) {
                         continue;
                 }
 
-                r = routing_policy_rule_configure(rule, link, NULL, false);
+                r = routing_policy_rule_configure(rule, link, NULL);
                 if (r < 0) {
                         log_link_warning_errno(link, r, "Could not set routing policy rules: %m");
                         link_enter_failed(link);
                         return r;
                 }
-
-                link->routing_policy_rule_messages++;
+                if (r > 0)
+                        link->routing_policy_rule_messages++;
         }
 
         routing_policy_rule_purge(link->manager, link);
@@ -909,8 +913,8 @@ int link_request_set_routes(Link *link) {
                                 link_enter_failed(link);
                                 return r;
                         }
-
-                        link->route_messages++;
+                        if (r > 0)
+                                link->route_messages++;
                 }
 
         if (link->route_messages == 0) {
@@ -947,6 +951,7 @@ void link_check_ready(Link *link) {
         if (!link->addresses_ready) {
                 link->addresses_ready = true;
                 link_request_set_routes(link);
+                return;
         }
 
         if (!link->static_routes_configured)
@@ -955,7 +960,7 @@ void link_check_ready(Link *link) {
         if (!link->routing_policy_rules_configured)
                 return;
 
-        if (link_ipv4ll_enabled(link) && !(link->ipv4ll_address && link->ipv4ll_route))
+        if (link_ipv4ll_enabled(link, ADDRESS_FAMILY_IPV4) && !(link->ipv4ll_address && link->ipv4ll_route))
                 return;
 
         if (link_ipv6ll_enabled(link) &&
@@ -963,8 +968,9 @@ void link_check_ready(Link *link) {
                 return;
 
         if ((link_dhcp4_enabled(link) || link_dhcp6_enabled(link)) &&
-            !(link->dhcp4_configured || link->dhcp6_configured) &&
-            !(link_ipv4ll_fallback_enabled(link) && link->ipv4ll_address && link->ipv4ll_route))
+            !link->dhcp4_configured &&
+            !link->dhcp6_configured &&
+            !(link_ipv4ll_enabled(link, ADDRESS_FAMILY_FALLBACK_IPV4) && link->ipv4ll_address && link->ipv4ll_route))
                 /* When DHCP is enabled, at least one protocol must provide an address, or
                  * an IPv4ll fallback address must be configured. */
                 return;
@@ -1188,8 +1194,8 @@ static int link_request_set_addresses(Link *link) {
                         link_enter_failed(link);
                         return r;
                 }
-
-                link->address_messages++;
+                if (r > 0)
+                        link->address_messages++;
         }
 
         LIST_FOREACH(labels, label, link->network->address_labels) {
@@ -1331,7 +1337,7 @@ static int link_request_set_addresses(Link *link) {
 }
 
 static int link_set_bridge_vlan(Link *link) {
-        int r = 0;
+        int r;
 
         r = br_vlan_configure(link, link->network->pvid, link->network->br_vid_bitmap, link->network->br_untagged_bitmap);
         if (r < 0)
@@ -1353,22 +1359,6 @@ static int link_set_proxy_arp(Link *link) {
         return 0;
 }
 
-static int link_set_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        int r;
-
-        assert(link);
-
-        log_link_debug(link, "Set link");
-
-        r = sd_netlink_message_get_errno(m);
-        if (r < 0 && r != -EEXIST) {
-                log_link_error_errno(link, r, "Could not join netdev: %m");
-                link_enter_failed(link);
-        }
-
-        return 1;
-}
-
 static int link_configure_after_setting_mtu(Link *link);
 
 static int set_mtu_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
@@ -1397,7 +1387,7 @@ static int set_mtu_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link)
         return 1;
 }
 
-int link_set_mtu(Link *link, uint32_t mtu, bool force) {
+int link_set_mtu(Link *link, uint32_t mtu) {
         _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
         int r;
 
@@ -1408,7 +1398,7 @@ int link_set_mtu(Link *link, uint32_t mtu, bool force) {
         if (mtu == 0 || link->setting_mtu)
                 return 0;
 
-        if (force ? link->mtu == mtu : link->mtu >= mtu)
+        if (link->mtu == mtu)
                 return 0;
 
         log_link_debug(link, "Setting MTU: %" PRIu32, mtu);
@@ -1446,6 +1436,48 @@ int link_set_mtu(Link *link, uint32_t mtu, bool force) {
         return 0;
 }
 
+static bool link_reduces_vlan_mtu(Link *link) {
+        /* See netif_reduces_vlan_mtu() in kernel. */
+        return streq_ptr(link->kind, "macsec");
+}
+
+static uint32_t link_get_requested_mtu_by_stacked_netdevs(Link *link) {
+        uint32_t mtu = 0;
+        NetDev *dev;
+        Iterator i;
+
+        HASHMAP_FOREACH(dev, link->network->stacked_netdevs, i)
+                if (dev->kind == NETDEV_KIND_VLAN && dev->mtu > 0)
+                        /* See vlan_dev_change_mtu() in kernel. */
+                        mtu = MAX(mtu, link_reduces_vlan_mtu(link) ? dev->mtu + 4 : dev->mtu);
+
+                else if (dev->kind == NETDEV_KIND_MACVLAN && dev->mtu > mtu)
+                        /* See macvlan_change_mtu() in kernel. */
+                        mtu = dev->mtu;
+
+        return mtu;
+}
+
+static int link_configure_mtu(Link *link) {
+        uint32_t mtu;
+
+        assert(link);
+        assert(link->network);
+
+        if (link->network->mtu > 0)
+                return link_set_mtu(link, link->network->mtu);
+
+        mtu = link_get_requested_mtu_by_stacked_netdevs(link);
+        if (link->mtu >= mtu)
+                return 0;
+
+        log_link_notice(link, "Bumping MTU bytes from %"PRIu32" to %"PRIu32" because of stacked device. "
+                        "If it is not desired, then please explicitly specify MTUBytes= setting.",
+                        link->mtu, mtu);
+
+        return link_set_mtu(link, mtu);
+}
+
 static int set_flags_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
         int r;
 
@@ -1515,195 +1547,6 @@ static int link_set_flags(Link *link) {
         return 0;
 }
 
-static int link_set_bridge(Link *link) {
-        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
-        int r;
-
-        assert(link);
-        assert(link->network);
-
-        r = sd_rtnl_message_new_link(link->manager->rtnl, &req, RTM_SETLINK, link->ifindex);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not allocate RTM_SETLINK message: %m");
-
-        r = sd_rtnl_message_link_set_family(req, PF_BRIDGE);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not set message family: %m");
-
-        r = sd_netlink_message_open_container(req, IFLA_PROTINFO);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not append IFLA_PROTINFO attribute: %m");
-
-        if (link->network->use_bpdu >= 0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_GUARD, link->network->use_bpdu);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_GUARD attribute: %m");
-        }
-
-        if (link->network->hairpin >= 0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_MODE, link->network->hairpin);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_MODE attribute: %m");
-        }
-
-        if (link->network->fast_leave >= 0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_FAST_LEAVE, link->network->fast_leave);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_FAST_LEAVE attribute: %m");
-        }
-
-        if (link->network->allow_port_to_be_root >=  0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_PROTECT, link->network->allow_port_to_be_root);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_PROTECT attribute: %m");
-        }
-
-        if (link->network->unicast_flood >= 0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_UNICAST_FLOOD, link->network->unicast_flood);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_UNICAST_FLOOD attribute: %m");
-        }
-
-        if (link->network->multicast_flood >= 0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_MCAST_FLOOD, link->network->multicast_flood);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_MCAST_FLOOD attribute: %m");
-        }
-
-        if (link->network->multicast_to_unicast >= 0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_MCAST_TO_UCAST, link->network->multicast_to_unicast);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_MCAST_TO_UCAST attribute: %m");
-        }
-
-        if (link->network->neighbor_suppression >= 0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_NEIGH_SUPPRESS, link->network->neighbor_suppression);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_NEIGH_SUPPRESS attribute: %m");
-        }
-
-        if (link->network->learning >= 0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_LEARNING, link->network->learning);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_LEARNING attribute: %m");
-        }
-
-        if (link->network->bridge_proxy_arp >= 0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_PROXYARP, link->network->bridge_proxy_arp);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_PROXYARP attribute: %m");
-        }
-
-        if (link->network->bridge_proxy_arp_wifi >= 0) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_PROXYARP_WIFI, link->network->bridge_proxy_arp_wifi);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_PROXYARP_WIFI attribute: %m");
-        }
-
-        if (link->network->cost != 0) {
-                r = sd_netlink_message_append_u32(req, IFLA_BRPORT_COST, link->network->cost);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_COST attribute: %m");
-        }
-
-        if (link->network->priority != LINK_BRIDGE_PORT_PRIORITY_INVALID) {
-                r = sd_netlink_message_append_u16(req, IFLA_BRPORT_PRIORITY, link->network->priority);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_PRIORITY attribute: %m");
-        }
-
-        if (link->network->multicast_router != _MULTICAST_ROUTER_INVALID) {
-                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_MULTICAST_ROUTER, link->network->multicast_router);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_MULTICAST_ROUTER attribute: %m");
-        }
-
-        r = sd_netlink_message_close_container(req);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not append IFLA_LINKINFO attribute: %m");
-
-        r = netlink_call_async(link->manager->rtnl, NULL, req, link_set_handler,
-                               link_netlink_destroy_callback, link);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not send rtnetlink message: %m");
-
-        link_ref(link);
-
-        return r;
-}
-
-static int link_set_bond_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        int r;
-
-        assert(m);
-        assert(link);
-        assert(link->ifname);
-
-        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
-                return 1;
-
-        r = sd_netlink_message_get_errno(m);
-        if (r < 0) {
-                log_link_warning_errno(link, r, "Could not set bonding interface: %m");
-                return 1;
-        }
-
-        return 1;
-}
-
-static int link_set_bond(Link *link) {
-        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
-        int r;
-
-        assert(link);
-        assert(link->network);
-
-        r = sd_rtnl_message_new_link(link->manager->rtnl, &req, RTM_NEWLINK, link->network->bond->ifindex);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not allocate RTM_SETLINK message: %m");
-
-        r = sd_netlink_message_set_flags(req, NLM_F_REQUEST | NLM_F_ACK);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not set netlink flags: %m");
-
-        r = sd_netlink_message_open_container(req, IFLA_LINKINFO);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not append IFLA_PROTINFO attribute: %m");
-
-        r = sd_netlink_message_open_container_union(req, IFLA_INFO_DATA, "bond");
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not append IFLA_INFO_DATA attribute: %m");
-
-        if (link->network->active_slave) {
-                r = sd_netlink_message_append_u32(req, IFLA_BOND_ACTIVE_SLAVE, link->ifindex);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BOND_ACTIVE_SLAVE attribute: %m");
-        }
-
-        if (link->network->primary_slave) {
-                r = sd_netlink_message_append_u32(req, IFLA_BOND_PRIMARY, link->ifindex);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_BOND_PRIMARY attribute: %m");
-        }
-
-        r = sd_netlink_message_close_container(req);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not append IFLA_LINKINFO attribute: %m");
-
-        r = sd_netlink_message_close_container(req);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not append IFLA_INFO_DATA attribute: %m");
-
-        r = netlink_call_async(link->manager->rtnl, NULL, req, link_set_bond_handler,
-                               link_netlink_destroy_callback, link);
-        if (r < 0)
-                return log_link_error_errno(link, r,  "Could not send rtnetlink message: %m");
-
-        link_ref(link);
-
-        return r;
-}
-
 static int link_acquire_ipv6_conf(Link *link) {
         int r;
 
@@ -1742,7 +1585,7 @@ static int link_acquire_ipv4_conf(Link *link) {
         assert(link->manager);
         assert(link->manager->event);
 
-        if (link_ipv4ll_enabled(link)) {
+        if (link_ipv4ll_enabled(link, ADDRESS_FAMILY_IPV4)) {
                 assert(link->ipv4ll);
 
                 log_link_debug(link, "Acquiring IPv4 link-local address");
@@ -1797,7 +1640,8 @@ bool link_has_carrier(Link *link) {
 
         if (link->kernel_operstate == IF_OPER_UNKNOWN)
                 /* operstate may not be implemented, so fall back to flags */
-                if ((link->flags & IFF_LOWER_UP) && !(link->flags & IFF_DORMANT))
+                if (FLAGS_SET(link->flags, IFF_LOWER_UP | IFF_RUNNING) &&
+                    !FLAGS_SET(link->flags, IFF_DORMANT))
                         return true;
 
         return false;
@@ -1828,6 +1672,9 @@ static int link_configure_addrgen_mode(Link *link) {
         assert(link->manager);
         assert(link->manager->rtnl);
 
+        if (!socket_ipv6_is_supported())
+                return 0;
+
         log_link_debug(link, "Setting address genmode for link");
 
         r = sd_rtnl_message_new_link(link->manager->rtnl, &req, RTM_SETLINK, link->ifindex);
@@ -1921,46 +1768,6 @@ static int link_up(Link *link) {
                         return log_link_error_errno(link, r, "Could not set MAC address: %m");
         }
 
-        if (link_ipv6_enabled(link)) {
-                uint8_t ipv6ll_mode;
-
-                r = sd_netlink_message_open_container(req, IFLA_AF_SPEC);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not open IFLA_AF_SPEC container: %m");
-
-                /* if the kernel lacks ipv6 support setting IFF_UP fails if any ipv6 options are passed */
-                r = sd_netlink_message_open_container(req, AF_INET6);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not open AF_INET6 container: %m");
-
-                if (!in_addr_is_null(AF_INET6, &link->network->ipv6_token)) {
-                        r = sd_netlink_message_append_in6_addr(req, IFLA_INET6_TOKEN, &link->network->ipv6_token.in6);
-                        if (r < 0)
-                                return log_link_error_errno(link, r, "Could not append IFLA_INET6_TOKEN: %m");
-                }
-
-                if (!link_ipv6ll_enabled(link))
-                        ipv6ll_mode = IN6_ADDR_GEN_MODE_NONE;
-                else if (sysctl_read_ip_property(AF_INET6, link->ifname, "stable_secret", NULL) < 0)
-                        /* The file may not exist. And event if it exists, when stable_secret is unset,
-                         * reading the file fails with EIO. */
-                        ipv6ll_mode = IN6_ADDR_GEN_MODE_EUI64;
-                else
-                        ipv6ll_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
-
-                r = sd_netlink_message_append_u8(req, IFLA_INET6_ADDR_GEN_MODE, ipv6ll_mode);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_INET6_ADDR_GEN_MODE: %m");
-
-                r = sd_netlink_message_close_container(req);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not close AF_INET6 container: %m");
-
-                r = sd_netlink_message_close_container(req);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not close IFLA_AF_SPEC container: %m");
-        }
-
         r = netlink_call_async(link->manager->rtnl, NULL, req, link_up_handler,
                                link_netlink_destroy_callback, link);
         if (r < 0)
@@ -1971,145 +1778,6 @@ static int link_up(Link *link) {
         return 0;
 }
 
-static int link_up_can(Link *link) {
-        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
-        int r;
-
-        assert(link);
-
-        log_link_debug(link, "Bringing CAN link up");
-
-        r = sd_rtnl_message_new_link(link->manager->rtnl, &req, RTM_SETLINK, link->ifindex);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not allocate RTM_SETLINK message: %m");
-
-        r = sd_rtnl_message_link_set_flags(req, IFF_UP, IFF_UP);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not set link flags: %m");
-
-        r = netlink_call_async(link->manager->rtnl, NULL, req, link_up_handler,
-                               link_netlink_destroy_callback, link);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not send rtnetlink message: %m");
-
-        link_ref(link);
-
-        return 0;
-}
-
-static int link_set_can(Link *link) {
-        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
-        int r;
-
-        assert(link);
-        assert(link->network);
-        assert(link->manager);
-        assert(link->manager->rtnl);
-
-        log_link_debug(link, "link_set_can");
-
-        r = sd_rtnl_message_new_link(link->manager->rtnl, &m, RTM_NEWLINK, link->ifindex);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Failed to allocate netlink message: %m");
-
-        r = sd_netlink_message_set_flags(m, NLM_F_REQUEST | NLM_F_ACK);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not set netlink flags: %m");
-
-        r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Failed to open netlink container: %m");
-
-        r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, link->kind);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not append IFLA_INFO_DATA attribute: %m");
-
-        if (link->network->can_bitrate > 0 || link->network->can_sample_point > 0) {
-                struct can_bittiming bt = {
-                        .bitrate = link->network->can_bitrate,
-                        .sample_point = link->network->can_sample_point,
-                };
-
-                if (link->network->can_bitrate > UINT32_MAX) {
-                        log_link_error(link, "bitrate (%zu) too big.", link->network->can_bitrate);
-                        return -ERANGE;
-                }
-
-                log_link_debug(link, "Setting bitrate = %d bit/s", bt.bitrate);
-                if (link->network->can_sample_point > 0)
-                        log_link_debug(link, "Setting sample point = %d.%d%%", bt.sample_point / 10, bt.sample_point % 10);
-                else
-                        log_link_debug(link, "Using default sample point");
-
-                r = sd_netlink_message_append_data(m, IFLA_CAN_BITTIMING, &bt, sizeof(bt));
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_CAN_BITTIMING attribute: %m");
-        }
-
-        if (link->network->can_restart_us > 0) {
-                char time_string[FORMAT_TIMESPAN_MAX];
-                uint64_t restart_ms;
-
-                if (link->network->can_restart_us == USEC_INFINITY)
-                        restart_ms = 0;
-                else
-                        restart_ms = DIV_ROUND_UP(link->network->can_restart_us, USEC_PER_MSEC);
-
-                format_timespan(time_string, FORMAT_TIMESPAN_MAX, restart_ms * 1000, MSEC_PER_SEC);
-
-                if (restart_ms > UINT32_MAX) {
-                        log_link_error(link, "restart timeout (%s) too big.", time_string);
-                        return -ERANGE;
-                }
-
-                log_link_debug(link, "Setting restart = %s", time_string);
-
-                r = sd_netlink_message_append_u32(m, IFLA_CAN_RESTART_MS, restart_ms);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_CAN_RESTART_MS attribute: %m");
-        }
-
-        if (link->network->can_triple_sampling >= 0) {
-                struct can_ctrlmode cm = {
-                        .mask = CAN_CTRLMODE_3_SAMPLES,
-                        .flags = link->network->can_triple_sampling ? CAN_CTRLMODE_3_SAMPLES : 0,
-                };
-
-                log_link_debug(link, "%sabling triple-sampling", link->network->can_triple_sampling ? "En" : "Dis");
-
-                r = sd_netlink_message_append_data(m, IFLA_CAN_CTRLMODE, &cm, sizeof(cm));
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_CAN_CTRLMODE attribute: %m");
-        }
-
-        r = sd_netlink_message_close_container(m);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Failed to close netlink container: %m");
-
-        r = sd_netlink_message_close_container(m);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Failed to close netlink container: %m");
-
-        r = netlink_call_async(link->manager->rtnl, NULL, m, link_set_handler,
-                               link_netlink_destroy_callback, link);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not send rtnetlink message: %m");
-
-        link_ref(link);
-
-        if (!(link->flags & IFF_UP)) {
-                r = link_up_can(link);
-                if (r < 0) {
-                        link_enter_failed(link);
-                        return r;
-                }
-        }
-
-        log_link_debug(link, "link_set_can done");
-
-        return r;
-}
-
 static int link_down_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
         int r;
 
@@ -2122,9 +1790,6 @@ static int link_down_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link
         if (r < 0)
                 log_link_warning_errno(link, r, "Could not bring down interface: %m");
 
-        if (streq_ptr(link->kind, "can"))
-                link_set_can(link);
-
         return 1;
 }
 
@@ -2519,7 +2184,6 @@ static int netdev_join_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *li
         assert(link);
         assert(link->network);
         assert(link->enslaving > 0);
-        assert(!link->enslaved_raw);
 
         link->enslaving--;
 
@@ -2535,7 +2199,6 @@ static int netdev_join_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *li
                 log_link_debug(link, "Joined netdev");
 
         if (link->enslaving == 0) {
-                link->enslaved_raw = true;
                 link_joined(link);
         }
 
@@ -2555,7 +2218,6 @@ static int link_enter_join_netdev(Link *link) {
 
         link_dirty(link);
         link->enslaving = 0;
-        link->enslaved_raw = false;
 
         if (link->network->bond) {
                 if (link->network->bond->state == NETDEV_STATE_READY &&
@@ -2826,6 +2488,33 @@ static bool link_is_static_route_configured(Link *link, Route *route) {
         return false;
 }
 
+static bool link_address_is_dynamic(Link *link, Address *address) {
+        Route *route;
+        Iterator i;
+
+        assert(link);
+        assert(address);
+
+        if (address->cinfo.ifa_prefered != CACHE_INFO_INFINITY_LIFE_TIME)
+                return true;
+
+        /* Even when the address is leased from a DHCP server, networkd assign the address
+         * without lifetime when KeepConfiguration=dhcp. So, let's check that we have
+         * corresponding routes with RTPROT_DHCP. */
+        SET_FOREACH(route, link->routes_foreign, i) {
+                if (route->protocol != RTPROT_DHCP)
+                        continue;
+
+                if (address->family != route->family)
+                        continue;
+
+                if (in_addr_equal(address->family, &address->in_addr, &route->prefsrc))
+                        return true;
+        }
+
+        return false;
+}
+
 static int link_drop_foreign_config(Link *link) {
         Address *address;
         Route *route;
@@ -2837,6 +2526,12 @@ static int link_drop_foreign_config(Link *link) {
                 if (address->family == AF_INET6 && in_addr_is_link_local(AF_INET6, &address->in_addr) == 1)
                         continue;
 
+                if (link_address_is_dynamic(link, address)) {
+                        if (FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_DHCP))
+                                continue;
+                } else if (FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_STATIC))
+                        continue;
+
                 if (link_is_static_address_configured(link, address)) {
                         r = address_add(link, address->family, &address->in_addr, address->prefixlen, NULL);
                         if (r < 0)
@@ -2853,6 +2548,14 @@ static int link_drop_foreign_config(Link *link) {
                 if (route->protocol == RTPROT_KERNEL)
                         continue;
 
+                if (route->protocol == RTPROT_STATIC &&
+                    FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_STATIC))
+                        continue;
+
+                if (route->protocol == RTPROT_DHCP &&
+                    FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_DHCP))
+                        continue;
+
                 if (link_is_static_route_configured(link, route)) {
                         r = route_add(link, route->family, &route->dst, route->dst_prefixlen, route->tos, route->priority, route->table, NULL);
                         if (r < 0)
@@ -2907,35 +2610,6 @@ static int link_drop_config(Link *link) {
         return 0;
 }
 
-static int link_configure_can(Link *link) {
-        int r;
-
-        if (streq_ptr(link->kind, "can")) {
-                /* The CAN interface must be down to configure bitrate, etc... */
-                if ((link->flags & IFF_UP)) {
-                        r = link_down(link, NULL);
-                        if (r < 0) {
-                                link_enter_failed(link);
-                                return r;
-                        }
-
-                        return 0;
-                }
-
-                return link_set_can(link);
-        }
-
-        if (!(link->flags & IFF_UP)) {
-                r = link_up_can(link);
-                if (r < 0) {
-                        link_enter_failed(link);
-                        return r;
-                }
-        }
-
-        return 0;
-}
-
 static int link_configure(Link *link) {
         int r;
 
@@ -2943,12 +2617,13 @@ static int link_configure(Link *link) {
         assert(link->network);
         assert(link->state == LINK_STATE_INITIALIZED);
 
-        if (STRPTR_IN_SET(link->kind, "can", "vcan"))
+        if (STRPTR_IN_SET(link->kind, "can", "vcan", "vxcan"))
                 return link_configure_can(link);
 
         /* Drop foreign config, but ignore loopback or critical devices.
          * We do not want to remove loopback address or addresses used for root NFS. */
-        if (!(link->flags & IFF_LOOPBACK) && !(link->network->dhcp_critical)) {
+        if (!(link->flags & IFF_LOOPBACK) &&
+            link->network->keep_configuration != KEEP_CONFIGURATION_YES) {
                 r = link_drop_foreign_config(link);
                 if (r < 0)
                         return r;
@@ -2994,7 +2669,7 @@ static int link_configure(Link *link) {
         if (r < 0)
                 return r;
 
-        if (link_ipv4ll_enabled(link) || link_ipv4ll_fallback_enabled(link)) {
+        if (link_ipv4ll_enabled(link, ADDRESS_FAMILY_IPV4 | ADDRESS_FAMILY_FALLBACK_IPV4)) {
                 r = ipv4ll_configure(link);
                 if (r < 0)
                         return r;
@@ -3045,15 +2720,13 @@ static int link_configure(Link *link) {
                         return r;
         }
 
-        r = link_set_mtu(link, link->network->mtu, link->network->mtu_is_set);
+        r = link_configure_mtu(link);
         if (r < 0)
                 return r;
 
-        if (socket_ipv6_is_supported()) {
-                r = link_configure_addrgen_mode(link);
-                if (r < 0)
-                        return r;
-        }
+        r = link_configure_addrgen_mode(link);
+        if (r < 0)
+                return r;
 
         return link_configure_after_setting_mtu(link);
 }
@@ -3636,7 +3309,7 @@ static int link_carrier_lost(Link *link) {
         if (link->setting_mtu)
                 return 0;
 
-        r = link_stop_clients(link);
+        r = link_stop_clients(link, false);
         if (r < 0) {
                 link_enter_failed(link);
                 return r;
@@ -3688,7 +3361,7 @@ int link_update(Link *link, sd_netlink_message *m) {
         const char *ifname;
         uint32_t mtu;
         bool had_carrier, carrier_gained, carrier_lost;
-        int r;
+        int old_master, r;
 
         assert(link);
         assert(link->ifname);
@@ -3814,9 +3487,12 @@ int link_update(Link *link, sd_netlink_message *m) {
                 }
         }
 
+        old_master = link->master_ifindex;
+        (void) sd_netlink_message_read_u32(m, IFLA_MASTER, (uint32_t *) &link->master_ifindex);
+
         had_carrier = link_has_carrier(link);
 
-        r = link_update_flags(link, m);
+        r = link_update_flags(link, m, old_master != link->master_ifindex);
         if (r < 0)
                 return r;
 
@@ -3907,12 +3583,11 @@ int link_save(Link *link) {
                 admin_state, oper_state);
 
         if (link->network) {
-                bool space;
+                char **dhcp6_domains = NULL, **dhcp_domains = NULL;
+                const char *dhcp_domainname = NULL, *p;
                 sd_dhcp6_lease *dhcp6_lease = NULL;
-                const char *dhcp_domainname = NULL;
-                char **dhcp6_domains = NULL;
-                char **dhcp_domains = NULL;
                 unsigned j;
+                bool space;
 
                 fprintf(f, "REQUIRED_FOR_ONLINE=%s\n",
                         yes_no(link->network->required_for_online));
@@ -4029,7 +3704,10 @@ int link_save(Link *link) {
                                 (void) sd_dhcp6_lease_get_domains(dhcp6_lease, &dhcp6_domains);
                 }
 
-                ordered_set_print(f, "DOMAINS=", link->network->search_domains);
+                fputs("DOMAINS=", f);
+                space = false;
+                ORDERED_SET_FOREACH(p, link->network->search_domains, i)
+                        fputs_with_space(f, p, NULL, &space);
 
                 if (link->network->dhcp_use_domains == DHCP_USE_DOMAINS_YES) {
                         NDiscDNSSL *dd;
@@ -4047,7 +3725,10 @@ int link_save(Link *link) {
 
                 fputc('\n', f);
 
-                ordered_set_print(f, "ROUTE_DOMAINS=", link->network->route_domains);
+                fputs("ROUTE_DOMAINS=", f);
+                space = false;
+                ORDERED_SET_FOREACH(p, link->network->route_domains, i)
+                        fputs_with_space(f, p, NULL, &space);
 
                 if (link->network->dhcp_use_domains == DHCP_USE_DOMAINS_ROUTE) {
                         NDiscDNSSL *dd;