networkd-link.c revision ecd2f2c5947d9e2f4d6792c2a3a90b8ced6a5b3e
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2013 Tom Gundersen <teg@jklm.no>
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <netinet/ether.h>
#include <linux/if.h>
#include "networkd.h"
#include "libudev-private.h"
#include "util.h"
#include "bus-util.h"
#include "net-util.h"
int link_new(Manager *manager, struct udev_device *device, Link **ret) {
_cleanup_link_free_ Link *link = NULL;
const char *mac;
struct ether_addr *mac_addr;
const char *ifname;
int r;
assert(device);
assert(ret);
link = new0(Link, 1);
if (!link)
return -ENOMEM;
link->manager = manager;
link->state = _LINK_STATE_INVALID;
link->ifindex = udev_device_get_ifindex(device);
if (link->ifindex <= 0)
return -EINVAL;
mac = udev_device_get_sysattr_value(device, "address");
if (mac) {
mac_addr = ether_aton(mac);
if (mac_addr)
memcpy(&link->mac, mac_addr, sizeof(struct ether_addr));
}
ifname = udev_device_get_sysname(device);
link->ifname = strdup(ifname);
r = hashmap_put(manager->links, &link->ifindex, link);
if (r < 0)
return r;
*ret = link;
link = NULL;
return 0;
}
void link_free(Link *link) {
if (!link)
return;
assert(link->manager);
sd_dhcp_client_free(link->dhcp_client);
sd_dhcp_lease_unref(link->dhcp_lease);
hashmap_remove(link->manager->links, &link->ifindex);
free(link->ifname);
free(link);
}
int link_add(Manager *m, struct udev_device *device, Link **ret) {
Link *link;
Network *network;
int r;
uint64_t ifindex;
assert(m);
assert(device);
ifindex = udev_device_get_ifindex(device);
link = hashmap_get(m->links, &ifindex);
if (link) {
*ret = link;
return -EEXIST;
}
r = link_new(m, device, &link);
if (r < 0)
return r;
*ret = link;
r = network_get(m, device, &network);
if (r < 0)
return r == -ENOENT ? 0 : r;
r = network_apply(m, network, link);
if (r < 0)
return r;
return 0;
}
static int link_enter_configured(Link *link) {
assert(link);
assert(link->state == LINK_STATE_SETTING_ROUTES);
log_info_link(link, "link configured");
link->state = LINK_STATE_CONFIGURED;
return 0;
}
static void link_enter_failed(Link *link) {
assert(link);
log_warning_link(link, "failed");
link->state = LINK_STATE_FAILED;
}
static int route_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
Link *link = userdata;
int r;
assert(link->route_messages > 0);
assert(link->state == LINK_STATE_SETTING_ADDRESSES ||
link->state == LINK_STATE_SETTING_ROUTES ||
link->state == LINK_STATE_FAILED);
link->route_messages --;
if (link->state == LINK_STATE_FAILED)
return 1;
r = sd_rtnl_message_get_errno(m);
if (r < 0 && r != -EEXIST)
log_struct_link(LOG_WARNING, link,
"MESSAGE=%s: could not set route: %s",
link->ifname, strerror(-r),
"ERRNO=%d", -r,
NULL);
/* we might have received an old reply after moving back to SETTING_ADDRESSES,
* ignore it */
if (link->route_messages == 0 && link->state == LINK_STATE_SETTING_ROUTES) {
log_debug_link(link, "routes set");
link_enter_configured(link);
}
return 1;
}
static int link_enter_set_routes(Link *link) {
Route *rt;
int r;
assert(link);
assert(link->network);
assert(link->state == LINK_STATE_SETTING_ADDRESSES);
link->state = LINK_STATE_SETTING_ROUTES;
if (!link->network->static_routes && !link->dhcp_lease)
return link_enter_configured(link);
log_debug_link(link, "setting routes");
LIST_FOREACH(static_routes, rt, link->network->static_routes) {
r = route_configure(rt, link, &route_handler);
if (r < 0) {
log_warning_link(link,
"could not set routes: %s", strerror(-r));
link_enter_failed(link);
return r;
}
link->route_messages ++;
}
if (link->dhcp_lease) {
_cleanup_route_free_ Route *route = NULL;
struct in_addr gateway;
r = sd_dhcp_lease_get_router(link->dhcp_lease, &gateway);
if (r < 0) {
log_warning_link(link, "DHCP error: no router: %s",
strerror(-r));
return r;
}
r = route_new_dynamic(&route);
if (r < 0) {
log_error_link(link, "Could not allocate route: %s",
strerror(-r));
return r;
}
route->family = AF_INET;
route->in_addr.in = gateway;
r = route_configure(route, link, &route_handler);
if (r < 0) {
log_warning_link(link,
"could not set routes: %s", strerror(-r));
link_enter_failed(link);
return r;
}
link->route_messages ++;
}
return 0;
}
static int address_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
Link *link = userdata;
int r;
assert(m);
assert(link);
assert(link->ifname);
assert(link->addr_messages > 0);
assert(link->state == LINK_STATE_SETTING_ADDRESSES || link->state == LINK_STATE_FAILED);
link->addr_messages --;
if (link->state == LINK_STATE_FAILED)
return 1;
r = sd_rtnl_message_get_errno(m);
if (r < 0 && r != -EEXIST)
log_struct_link(LOG_WARNING, link,
"MESSAGE=%s: could not set address: %s",
link->ifname, strerror(-r),
"ERRNO=%d", -r,
NULL);
if (link->addr_messages == 0) {
log_debug_link(link, "addresses set");
link_enter_set_routes(link);
}
return 1;
}
static int link_enter_set_addresses(Link *link) {
Address *ad;
int r;
assert(link);
assert(link->network);
assert(link->state != _LINK_STATE_INVALID);
link->state = LINK_STATE_SETTING_ADDRESSES;
if (!link->network->static_addresses && !link->dhcp_lease)
return link_enter_set_routes(link);
log_debug_link(link, "setting addresses");
LIST_FOREACH(static_addresses, ad, link->network->static_addresses) {
r = address_configure(ad, link, &address_handler);
if (r < 0) {
log_warning_link(link,
"could not set addresses: %s", strerror(-r));
link_enter_failed(link);
return r;
}
link->addr_messages ++;
}
if (link->dhcp_lease) {
_cleanup_address_free_ Address *address = NULL;
struct in_addr addr;
struct in_addr netmask;
unsigned prefixlen;
r = sd_dhcp_lease_get_address(link->dhcp_lease, &addr);
if (r < 0) {
log_warning_link(link, "DHCP error: no address: %s",
strerror(-r));
return r;
}
r = sd_dhcp_lease_get_netmask(link->dhcp_lease, &netmask);
if (r < 0) {
log_warning_link(link, "DHCP error: no netmask: %s",
strerror(-r));
return r;
}
prefixlen = net_netmask_to_prefixlen(&netmask);
r = address_new_dynamic(&address);
if (r < 0) {
log_error_link(link, "Could not allocate address: %s",
strerror(-r));
return r;
}
address->family = AF_INET;
address->in_addr.in = addr;
address->prefixlen = prefixlen;
address->broadcast.s_addr = addr.s_addr | ~netmask.s_addr;
r = address_configure(address, link, &address_handler);
if (r < 0) {
log_warning_link(link,
"could not set addresses: %s", strerror(-r));
link_enter_failed(link);
return r;
}
link->addr_messages ++;
}
return 0;
}
static int address_drop_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
Link *link = userdata;
int r;
assert(m);
assert(link);
assert(link->ifname);
if (link->state == LINK_STATE_FAILED)
return 1;
r = sd_rtnl_message_get_errno(m);
if (r < 0 && r != -ENOENT)
log_struct_link(LOG_WARNING, link,
"MESSAGE=%s: could not drop address: %s",
link->ifname, strerror(-r),
"ERRNO=%d", -r,
NULL);
return 1;
}
static int set_hostname_handler(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *ret_error) {
int r;
r = sd_bus_message_get_errno(m);
if (r < 0)
log_warning("Could not set hostname: %s", strerror(-r));
return 1;
}
static int set_hostname(sd_bus *bus, const char *hostname) {
_cleanup_bus_message_unref_ sd_bus_message *m = NULL;
int r = 0;
assert(hostname);
log_debug("Setting transient hostname: '%s'", hostname);
if (!bus) { /* TODO: replace by assert when we can rely on kdbus */
log_info("Not connected to system bus, ignoring transient hostname.");
return 0;
}
r = sd_bus_message_new_method_call(
bus,
"org.freedesktop.hostname1",
"/org/freedesktop/hostname1",
"org.freedesktop.hostname1",
"SetHostname",
&m);
if (r < 0)
return r;
r = sd_bus_message_append(m, "sb", hostname, false);
if (r < 0)
return r;
r = sd_bus_call_async(bus, m, set_hostname_handler, NULL, 0, NULL);
if (r < 0)
log_error("Could not set transient hostname: %s", strerror(-r));
return r;
}
static int set_mtu_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
Link *link = userdata;
int r;
assert(m);
assert(link);
assert(link->ifname);
if (link->state == LINK_STATE_FAILED)
return 1;
r = sd_rtnl_message_get_errno(m);
if (r < 0)
log_struct_link(LOG_WARNING, link,
"MESSAGE=%s: could not set MTU: %s",
link->ifname, strerror(-r),
"ERRNO=%d", -r,
NULL);
return 1;
}
static int link_set_mtu(Link *link, uint32_t mtu) {
_cleanup_sd_rtnl_message_unref_ sd_rtnl_message *req = NULL;
int r;
assert(link);
assert(link->manager);
assert(link->manager->rtnl);
log_debug_link(link, "setting MTU: %" PRIu32, mtu);
r = sd_rtnl_message_link_new(RTM_SETLINK, link->ifindex, &req);
if (r < 0) {
log_error_link(link, "Could not allocate RTM_SETLINK message");
return r;
}
r = sd_rtnl_message_append_u32(req, IFLA_MTU, mtu);
if (r < 0) {
log_error_link(link, "Could not append MTU: %s", strerror(-r));
return r;
}
r = sd_rtnl_call_async(link->manager->rtnl, req, set_mtu_handler, link, 0, NULL);
if (r < 0) {
log_error_link(link,
"Could not send rtnetlink message: %s", strerror(-r));
return r;
}
return 0;
}
static int dhcp_lease_lost(Link *link) {
_cleanup_address_free_ Address *address = NULL;
struct in_addr addr;
struct in_addr netmask;
unsigned prefixlen;
int r;
assert(link);
assert(link->dhcp_lease);
r = address_new_dynamic(&address);
if (r >= 0) {
sd_dhcp_lease_get_address(link->dhcp_lease, &addr);
sd_dhcp_lease_get_netmask(link->dhcp_lease, &netmask);
prefixlen = net_netmask_to_prefixlen(&netmask);
address->family = AF_INET;
address->in_addr.in = addr;
address->prefixlen = prefixlen;
address_drop(address, link, address_drop_handler);
}
if (link->network->dhcp_mtu) {
uint16_t mtu;
r = sd_dhcp_lease_get_mtu(link->dhcp_lease, &mtu);
if (r >= 0 && link->original_mtu != mtu) {
r = link_set_mtu(link, link->original_mtu);
if (r < 0) {
log_warning_link(link, "DHCP error: could not reset MTU");
link_enter_failed(link);
return r;
}
}
}
if (link->network->dhcp_hostname) {
r = set_hostname(link->manager->bus, "");
if (r < 0)
log_error("Failed to reset transient hostname");
}
link->dhcp_lease = sd_dhcp_lease_unref(link->dhcp_lease);
return 0;
}
static int dhcp_lease_acquired(sd_dhcp_client *client, Link *link) {
sd_dhcp_lease *lease;
struct in_addr address;
struct in_addr netmask;
struct in_addr gateway;
unsigned prefixlen;
struct in_addr *nameservers;
size_t nameservers_size;
int r;
assert(client);
assert(link);
r = sd_dhcp_client_get_lease(client, &lease);
if (r < 0) {
log_warning_link(link, "DHCP error: no lease: %s",
strerror(-r));
return r;
}
r = sd_dhcp_lease_get_address(lease, &address);
if (r < 0) {
log_warning_link(link, "DHCP error: no address: %s",
strerror(-r));
return r;
}
r = sd_dhcp_lease_get_netmask(lease, &netmask);
if (r < 0) {
log_warning_link(link, "DHCP error: no netmask: %s",
strerror(-r));
return r;
}
prefixlen = net_netmask_to_prefixlen(&netmask);
r = sd_dhcp_lease_get_router(lease, &gateway);
if (r < 0) {
log_warning_link(link, "DHCP error: no router: %s",
strerror(-r));
return r;
}
log_struct_link(LOG_INFO, link,
"MESSAGE=%s: DHCPv4 address %u.%u.%u.%u/%u via %u.%u.%u.%u",
link->ifname,
ADDRESS_FMT_VAL(address),
prefixlen,
ADDRESS_FMT_VAL(gateway),
"ADDRESS=%u.%u.%u.%u",
ADDRESS_FMT_VAL(address),
"PREFIXLEN=%u",
prefixlen,
"GATEWAY=%u.%u.%u.%u",
ADDRESS_FMT_VAL(gateway),
NULL);
if (link->network->dhcp_dns) {
r = sd_dhcp_lease_get_dns(lease, &nameservers, &nameservers_size);
if (r >= 0) {
r = manager_update_resolv_conf(link->manager);
if (r < 0)
log_error("Failed to update resolv.conf");
}
}
if (link->network->dhcp_mtu) {
uint16_t mtu;
r = sd_dhcp_lease_get_mtu(lease, &mtu);
if (r >= 0) {
r = link_set_mtu(link, mtu);
if (r < 0)
log_error_link(link, "Failed to set MTU "
"to %" PRIu16, mtu);
}
}
if (link->network->dhcp_hostname) {
const char *hostname;
r = sd_dhcp_lease_get_hostname(lease, &hostname);
if (r >= 0) {
r = set_hostname(link->manager->bus, hostname);
if (r < 0)
log_error("Failed to set transient hostname "
"to '%s'", hostname);
}
}
link->dhcp_lease = lease;
link_enter_set_addresses(link);
return 0;
}
static void dhcp_handler(sd_dhcp_client *client, int event, void *userdata) {
Link *link = userdata;
int r;
assert(link);
assert(link->network);
assert(link->manager);
if (link->state == LINK_STATE_FAILED)
return;
switch (event) {
case DHCP_EVENT_NO_LEASE:
log_debug_link(link, "IP address in use.");
break;
case DHCP_EVENT_EXPIRED:
case DHCP_EVENT_STOP:
case DHCP_EVENT_IP_CHANGE:
if (link->network->dhcp_critical) {
log_error_link(link, "DHCPv4 connection considered system critical, "
"ignoring request to reconfigure it.");
return;
}
r = dhcp_lease_lost(link);
if (r < 0) {
link_enter_failed(link);
return;
}
if (event == DHCP_EVENT_IP_CHANGE) {
r = dhcp_lease_acquired(client, link);
if (r < 0) {
link_enter_failed(link);
return;
}
}
break;
case DHCP_EVENT_IP_ACQUIRE:
r = dhcp_lease_acquired(client, link);
if (r < 0) {
link_enter_failed(link);
return;
}
break;
default:
if (event < 0)
log_warning_link(link, "DHCP error: %s", strerror(-event));
else
log_warning_link(link, "DHCP unknown event: %d", event);
break;
}
return;
}
static int link_acquire_conf(Link *link) {
int r;
assert(link);
assert(link->network);
assert(link->network->dhcp);
assert(link->manager);
assert(link->manager->event);
if (!link->dhcp_client) {
r = sd_dhcp_client_new(&link->dhcp_client);
if (r < 0)
return r;
r = sd_dhcp_client_attach_event(link->dhcp_client, NULL, 0);
if (r < 0)
return r;
r = sd_dhcp_client_set_index(link->dhcp_client, link->ifindex);
if (r < 0)
return r;
r = sd_dhcp_client_set_mac(link->dhcp_client, &link->mac);
if (r < 0)
return r;
r = sd_dhcp_client_set_callback(link->dhcp_client, dhcp_handler, link);
if (r < 0)
return r;
if (link->network->dhcp_mtu) {
r = sd_dhcp_client_set_request_option(link->dhcp_client, 26);
if (r < 0)
return r;
}
}
log_debug_link(link, "acquiring DHCPv4 lease");
r = sd_dhcp_client_start(link->dhcp_client);
if (r < 0)
return r;
return 0;
}
static int link_update_flags(Link *link, unsigned flags) {
int r;
assert(link);
assert(link->network);
if (link->state == LINK_STATE_FAILED)
return 0;
if (link->flags == flags) {
log_debug_link(link, "link status unchanged: %#.8x", flags);
return 0;
}
if ((link->flags & IFF_UP) != (flags & IFF_UP))
log_info_link(link,
"link is %s", flags & IFF_UP ? "up": "down");
if ((link->flags & IFF_LOWER_UP) != (flags & IFF_LOWER_UP)) {
if (flags & IFF_LOWER_UP) {
log_info_link(link, "carrier on");
if (link->network->dhcp) {
r = link_acquire_conf(link);
if (r < 0) {
log_warning_link(link, "Could not acquire DHCPv4 lease: %s", strerror(-r));
link_enter_failed(link);
return r;
}
}
} else {
log_info_link(link, "carrier off");
if (link->network->dhcp) {
r = sd_dhcp_client_stop(link->dhcp_client);
if (r < 0) {
log_warning_link(link, "Could not stop DHCPv4 client: %s", strerror(-r));
link_enter_failed(link);
return r;
}
}
}
}
log_debug_link(link,
"link status updated: %#.8x -> %#.8x", link->flags, flags);
link->flags = flags;
return 0;
}
static int link_up_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
Link *link = userdata;
int r;
assert(link);
if (link->state == LINK_STATE_FAILED)
return 1;
r = sd_rtnl_message_get_errno(m);
if (r < 0) {
log_struct_link(LOG_ERR, link,
"MESSAGE=%s: could not bring up interface: %s",
link->ifname, strerror(-r),
"ERRNO=%d", -r,
NULL);
link_enter_failed(link);
return 1;
}
link_update_flags(link, link->flags | IFF_UP);
return 1;
}
static int link_up(Link *link) {
_cleanup_sd_rtnl_message_unref_ sd_rtnl_message *req = NULL;
int r;
assert(link);
assert(link->manager);
assert(link->manager->rtnl);
log_debug_link(link, "bringing link up");
r = sd_rtnl_message_link_new(RTM_SETLINK, link->ifindex, &req);
if (r < 0) {
log_error_link(link, "Could not allocate RTM_SETLINK message");
return r;
}
r = sd_rtnl_message_link_set_flags(req, IFF_UP, IFF_UP);
if (r < 0) {
log_error_link(link, "Could not set link flags: %s", strerror(-r));
return r;
}
r = sd_rtnl_call_async(link->manager->rtnl, req, link_up_handler, link, 0, NULL);
if (r < 0) {
log_error_link(link,
"Could not send rtnetlink message: %s", strerror(-r));
return r;
}
return 0;
}
static int link_enslaved(Link *link) {
int r;
assert(link);
assert(link->state == LINK_STATE_ENSLAVING);
assert(link->network);
r = link_up(link);
if (r < 0) {
link_enter_failed(link);
return r;
}
if (!link->network->dhcp)
return link_enter_set_addresses(link);
return 0;
}
static int enslave_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
Link *link = userdata;
int r;
assert(link);
assert(link->state == LINK_STATE_ENSLAVING || link->state == LINK_STATE_FAILED);
assert(link->network);
link->enslaving --;
if (link->state == LINK_STATE_FAILED)
return 1;
r = sd_rtnl_message_get_errno(m);
if (r < 0) {
log_struct_link(LOG_ERR, link,
"MESSAGE=%s: could not enslave: %s",
link->ifname, strerror(-r),
"ERRNO=%d", -r,
NULL);
link_enter_failed(link);
return 1;
}
log_debug_link(link, "enslaved");
if (link->enslaving == 0)
link_enslaved(link);
return 1;
}
static int link_enter_enslave(Link *link) {
int r;
assert(link);
assert(link->network);
assert(link->state == _LINK_STATE_INVALID);
link->state = LINK_STATE_ENSLAVING;
if (!link->network->bridge && !link->network->bond && !link->network->vlan)
return link_enslaved(link);
if (link->network->bridge) {
log_struct_link(LOG_DEBUG, link,
"MESSAGE=%s: enslaving by '%s'",
link->ifname, link->network->bridge->name,
NETDEV(link->network->bridge),
NULL);
r = netdev_enslave(link->network->bridge, link, &enslave_handler);
if (r < 0) {
log_struct_link(LOG_WARNING, link,
"MESSAGE=%s: could not enslave by '%s': %s",
link->ifname, link->network->bridge->name, strerror(-r),
NETDEV(link->network->bridge),
NULL);
link_enter_failed(link);
return r;
}
link->enslaving ++;
}
if (link->network->vlan) {
log_struct_link(LOG_DEBUG, link,
"MESSAGE=%s: enslaving by '%s'",
link->ifname, link->network->vlan->name,
NETDEV(link->network->vlan),
NULL);
r = netdev_enslave(link->network->vlan, link, &enslave_handler);
if (r < 0) {
log_struct_link(LOG_WARNING, link,
"MESSAGE=%s: could not enslave by '%s': %s",
link->ifname, link->network->vlan->name,
strerror(-r), NETDEV(link->network->vlan),
NULL);
link_enter_failed(link);
return r;
}
link->enslaving ++;
}
return 0;
}
static int link_get_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
Link *link = userdata;
int r;
assert(link);
if (link->state == LINK_STATE_FAILED)
return 1;
r = sd_rtnl_message_get_errno(m);
if (r < 0) {
log_struct_link(LOG_ERR, link,
"MESSAGE=%s: could not get state: %s",
link->ifname, strerror(-r),
"ERRNO=%d", -r,
NULL);
link_enter_failed(link);
return 1;
}
log_debug_link(link, "got link state");
link_update(link, m);
return 1;
}
static int link_get(Link *link) {
_cleanup_sd_rtnl_message_unref_ sd_rtnl_message *req = NULL;
int r;
assert(link);
assert(link->manager);
assert(link->manager->rtnl);
log_debug_link(link, "requesting link status");
r = sd_rtnl_message_link_new(RTM_GETLINK, link->ifindex, &req);
if (r < 0) {
log_error_link(link, "Could not allocate RTM_GETLINK message");
return r;
}
r = sd_rtnl_call_async(link->manager->rtnl, req, link_get_handler, link, 0, NULL);
if (r < 0) {
log_error_link(link,
"Could not send rtnetlink message: %s", strerror(-r));
return r;
}
return 0;
}
int link_configure(Link *link) {
int r;
assert(link);
assert(link->network);
assert(link->state == _LINK_STATE_INVALID);
r = link_get(link);
if (r < 0) {
link_enter_failed(link);
return r;
}
return link_enter_enslave(link);
}
int link_update(Link *link, sd_rtnl_message *m) {
unsigned flags;
void *data;
uint16_t type;
int r;
assert(link);
assert(m);
if (link->state == LINK_STATE_FAILED)
return 0;
r = sd_rtnl_message_link_get_flags(m, &flags);
if (r < 0) {
log_warning_link(link, "Could not get link flags");
return r;
}
while (sd_rtnl_message_read(m, &type, &data) > 0) {
if (type == IFLA_MTU && link->network->dhcp &&
link->network->dhcp_mtu && !link->original_mtu) {
link->original_mtu = *(uint16_t *) data;
log_debug_link(link, "saved original MTU: %" PRIu16,
link->original_mtu);
}
}
return link_update_flags(link, flags);
}