static int route_scope_from_address(const Route *route, const struct in_addr *self_addr) {
assert(route);
assert(self_addr);
if (in_addr_is_localhost(AF_INET, &route->dst) ||
(self_addr->s_addr && route->dst.in.s_addr == self_addr->s_addr))
return RT_SCOPE_HOST;
else if (in4_addr_is_null(&route->gw.in))
return RT_SCOPE_LINK;
else
return RT_SCOPE_UNIVERSE;
}
static int dhcp_lease_acquired(sd_dhcp_client *client, Link *link) {
const struct in_addr *router;
sd_dhcp_lease *lease;
struct in_addr address;
struct in_addr netmask;
unsigned prefixlen;
uint32_t lifetime = CACHE_INFO_INFINITY_LIFE_TIME;
int r;
assert(client);
assert(link);
r = sd_dhcp_client_get_lease(client, &lease);
if (r < 0)
return log_link_error_errno(link, r, "DHCP error: No lease: %m");
r = sd_dhcp_lease_get_address(lease, &address);
if (r < 0)
return log_link_error_errno(link, r, "DHCP error: No address: %m");
r = sd_dhcp_lease_get_netmask(lease, &netmask);
if (r < 0)
return log_link_error_errno(link, r, "DHCP error: No netmask: %m");
prefixlen = in4_addr_netmask_to_prefixlen(&netmask);
r = sd_dhcp_lease_get_router(lease, &router);
if (r < 0 && r != -ENODATA)
return log_link_error_errno(link, r, "DHCP error: Could not get gateway: %m");
if (r > 0 && !in4_addr_is_null(&router[0]))
log_struct(LOG_INFO,
LOG_LINK_INTERFACE(link),
LOG_LINK_MESSAGE(link, "DHCPv4 address %u.%u.%u.%u/%u via %u.%u.%u.%u",
ADDRESS_FMT_VAL(address),
prefixlen,
ADDRESS_FMT_VAL(router[0])),
"ADDRESS=%u.%u.%u.%u", ADDRESS_FMT_VAL(address),
"PREFIXLEN=%u", prefixlen,
"GATEWAY=%u.%u.%u.%u", ADDRESS_FMT_VAL(router[0]));
else
log_struct(LOG_INFO,
LOG_LINK_INTERFACE(link),
LOG_LINK_MESSAGE(link, "DHCPv4 address %u.%u.%u.%u/%u",
ADDRESS_FMT_VAL(address),
prefixlen),
"ADDRESS=%u.%u.%u.%u", ADDRESS_FMT_VAL(address),
"PREFIXLEN=%u", prefixlen);
link->dhcp_lease = sd_dhcp_lease_ref(lease);
link_dirty(link);
if (link->network->dhcp_use_mtu) {
uint16_t mtu;
r = sd_dhcp_lease_get_mtu(lease, &mtu);
if (r >= 0) {
r = link_set_mtu(link, mtu, true);
if (r < 0)
log_link_error_errno(link, r, "Failed to set MTU to %" PRIu16 ": %m", mtu);
}
}
if (link->network->dhcp_use_hostname) {
const char *dhcpname = NULL;
_cleanup_free_ char *hostname = NULL;
if (link->network->dhcp_hostname)
dhcpname = link->network->dhcp_hostname;
else
(void) sd_dhcp_lease_get_hostname(lease, &dhcpname);
if (dhcpname) {
r = shorten_overlong(dhcpname, &hostname);
if (r < 0)
log_link_warning_errno(link, r, "Unable to shorten overlong DHCP hostname '%s', ignoring: %m", dhcpname);
if (r == 1)
log_link_notice(link, "Overlong DHCP hostname received, shortened from '%s' to '%s'", dhcpname, hostname);
}
if (hostname) {
r = manager_set_hostname(link->manager, hostname);
if (r < 0)
log_link_error_errno(link, r, "Failed to set transient hostname to '%s': %m", hostname);
}
}
if (link->network->dhcp_use_timezone) {
const char *tz = NULL;
(void) sd_dhcp_lease_get_timezone(link->dhcp_lease, &tz);
if (tz) {
r = manager_set_timezone(link->manager, tz);
if (r < 0)
log_link_error_errno(link, r, "Failed to set timezone to '%s': %m", tz);
}
}
if (!link->network->dhcp_critical) {
r = sd_dhcp_lease_get_lifetime(link->dhcp_lease, &lifetime);
if (r < 0)
return log_link_warning_errno(link, r, "DHCP error: no lifetime: %m");
}
r = dhcp4_update_address(link, &address, &netmask, lifetime);
if (r < 0) {
log_link_warning_errno(link, r, "Could not update IP address: %m");
link_enter_failed(link);
return r;
}
return 0;
}
static int link_set_dhcp_routes(Link *link) {
_cleanup_free_ sd_dhcp_route **static_routes = NULL;
bool classless_route = false, static_route = false;
const struct in_addr *router;
struct in_addr address;
int r, n, i;
uint32_t table;
assert(link);
if (!link->dhcp_lease) /* link went down while we configured the IP addresses? */
return 0;
if (!link->network) /* link went down while we configured the IP addresses? */
return 0;
if (!link->network->dhcp_use_routes)
return 0;
table = link_get_dhcp_route_table(link);
r = sd_dhcp_lease_get_address(link->dhcp_lease, &address);
if (r < 0)
return log_link_warning_errno(link, r, "DHCP error: could not get address: %m");
n = sd_dhcp_lease_get_routes(link->dhcp_lease, &static_routes);
if (n == -ENODATA)
log_link_debug_errno(link, n, "DHCP: No routes received from DHCP server: %m");
else if (n < 0)
log_link_debug_errno(link, n, "DHCP error: could not get routes: %m");
for (i = 0; i < n; i++) {
switch (sd_dhcp_route_get_option(static_routes[i])) {
case SD_DHCP_OPTION_CLASSLESS_STATIC_ROUTE:
classless_route = true;
break;
case SD_DHCP_OPTION_STATIC_ROUTE:
static_route = true;
break;
}
}
for (i = 0; i < n; i++) {
_cleanup_(route_freep) Route *route = NULL;
/* if the DHCP server returns both a Classless Static Routes option and a Static Routes option,
the DHCP client MUST ignore the Static Routes option. */
if (classless_route &&
sd_dhcp_route_get_option(static_routes[i]) != SD_DHCP_OPTION_CLASSLESS_STATIC_ROUTE)
continue;
r = route_new(&route);
if (r < 0)
return log_link_error_errno(link, r, "Could not allocate route: %m");
route->family = AF_INET;
route->protocol = RTPROT_DHCP;
assert_se(sd_dhcp_route_get_gateway(static_routes[i], &route->gw.in) >= 0);
assert_se(sd_dhcp_route_get_destination(static_routes[i], &route->dst.in) >= 0);
assert_se(sd_dhcp_route_get_destination_prefix_length(static_routes[i], &route->dst_prefixlen) >= 0);
route->priority = link->network->dhcp_route_metric;
route->table = table;
route->scope = route_scope_from_address(route, &address);
r = route_configure(route, link, dhcp4_route_handler);
if (r < 0)
return log_link_warning_errno(link, r, "Could not set host route: %m");
link->dhcp4_messages++;
}
r = sd_dhcp_lease_get_router(link->dhcp_lease, &router);
if (IN_SET(r, 0, -ENODATA))
log_link_info(link, "DHCP: No gateway received from DHCP server.");
else if (r < 0)
log_link_warning_errno(link, r, "DHCP error: could not get gateway: %m");
else if (in4_addr_is_null(&router[0]))
log_link_info(link, "DHCP: Received gateway is null.");
/* According to RFC 3442: If the DHCP server returns both a Classless Static Routes option and
a Router option, the DHCP client MUST ignore the Router option. */
if (classless_route && static_route)
log_link_warning(link, "Classless static routes received from DHCP server: ignoring static-route option and router option");
if (r > 0 && !classless_route && !in4_addr_is_null(&router[0])) {
_cleanup_(route_freep) Route *route = NULL, *route_gw = NULL;
r = route_new(&route_gw);
if (r < 0)
return log_link_error_errno(link, r, "Could not allocate route: %m");
/* The dhcp netmask may mask out the gateway. Add an explicit
* route for the gw host so that we can route no matter the
* netmask or existing kernel route tables. */
route_gw->family = AF_INET;
route_gw->dst.in = router[0];
route_gw->dst_prefixlen = 32;
route_gw->prefsrc.in = address;
route_gw->scope = RT_SCOPE_LINK;
route_gw->protocol = RTPROT_DHCP;
route_gw->priority = link->network->dhcp_route_metric;
route_gw->table = table;
r = route_configure(route_gw, link, dhcp4_route_handler);
if (r < 0)
return log_link_warning_errno(link, r, "Could not set host route: %m");
link->dhcp4_messages++;
r = route_new(&route);
if (r < 0)
return log_link_error_errno(link, r, "Could not allocate route: %m");
route->family = AF_INET;
route->gw.in = router[0];
route->prefsrc.in = address;
route->protocol = RTPROT_DHCP;
route->priority = link->network->dhcp_route_metric;
route->table = table;
r = route_configure(route, link, dhcp4_route_handler);
if (r < 0) {
log_link_warning_errno(link, r, "Could not set routes: %m");
link_enter_failed(link);
return r;
}
link->dhcp4_messages++;
}
return 0;
}
static int dhcp_lease_lost(Link *link) {
_cleanup_(address_freep) Address *address = NULL;
const struct in_addr *router;
struct in_addr addr;
struct in_addr netmask;
unsigned prefixlen = 0;
int r;
assert(link);
assert(link->dhcp_lease);
log_link_warning(link, "DHCP lease lost");
if (link->network->dhcp_use_routes) {
_cleanup_free_ sd_dhcp_route **routes = NULL;
int n, i;
n = sd_dhcp_lease_get_routes(link->dhcp_lease, &routes);
if (n >= 0) {
for (i = 0; i < n; i++) {
_cleanup_(route_freep) Route *route = NULL;
r = route_new(&route);
if (r >= 0) {
route->family = AF_INET;
assert_se(sd_dhcp_route_get_gateway(routes[i], &route->gw.in) >= 0);
assert_se(sd_dhcp_route_get_destination(routes[i], &route->dst.in) >= 0);
assert_se(sd_dhcp_route_get_destination_prefix_length(routes[i], &route->dst_prefixlen) >= 0);
route_remove(route, link, NULL);
}
}
}
r = sd_dhcp_lease_get_router(link->dhcp_lease, &router);
if (r > 0 && !in4_addr_is_null(&router[0])) {
_cleanup_(route_freep) Route *route_gw = NULL;
_cleanup_(route_freep) Route *route = NULL;
r = route_new(&route_gw);
if (r >= 0) {
route_gw->family = AF_INET;
route_gw->dst.in = router[0];
route_gw->dst_prefixlen = 32;
route_gw->scope = RT_SCOPE_LINK;
route_remove(route_gw, link, NULL);
}
r = route_new(&route);
if (r >= 0) {
route->family = AF_INET;
route->gw.in = router[0];
route_remove(route, link, NULL);
}
}
}
r = address_new(&address);
if (r >= 0) {
r = sd_dhcp_lease_get_address(link->dhcp_lease, &addr);
if (r >= 0) {
r = sd_dhcp_lease_get_netmask(link->dhcp_lease, &netmask);
if (r >= 0)
prefixlen = in4_addr_netmask_to_prefixlen(&netmask);
address->family = AF_INET;
address->in_addr.in = addr;
address->prefixlen = prefixlen;
address_remove(address, link, NULL);
}
}
if (link->network->dhcp_use_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, true);
if (r < 0) {
log_link_warning(link,
"DHCP error: could not reset MTU");
link_enter_failed(link);
return r;
}
}
}
if (link->network->dhcp_use_hostname) {
const char *hostname = NULL;
if (link->network->dhcp_hostname)
hostname = link->network->dhcp_hostname;
else
(void) sd_dhcp_lease_get_hostname(link->dhcp_lease, &hostname);
if (hostname) {
/* If a hostname was set due to the lease, then unset it now. */
r = manager_set_hostname(link->manager, NULL);
if (r < 0)
log_link_warning_errno(link, r, "Failed to reset transient hostname: %m");
}
}
link->dhcp_lease = sd_dhcp_lease_unref(link->dhcp_lease);
link_dirty(link);
link->dhcp4_configured = false;
return 0;
}
