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Systemd/src/network/networkd-dhcp4.c
Yu Watanabe 4ff296b024 network: make link enter failed state when a configuration fails 
Some path of configuring address, route or etc., go to failed state, but
some do not. E.g., failure in address configuration which is provided by
DHCPv4 goes to failed state, but static address does not.

This is just for consistency. This should not change anything if
everything is fine.

This also voidify manager_rtnl_process_address().
2019-07-15 21:52:06 +09:00

1268 lines
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/* SPDX-License-Identifier: LGPL-2.1+ */
#include <netinet/in.h>
#include <linux/if.h>
#include "alloc-util.h"
#include "hostname-util.h"
#include "parse-util.h"
#include "network-internal.h"
#include "networkd-dhcp4.h"
#include "networkd-link.h"
#include "networkd-manager.h"
#include "networkd-network.h"
#include "string-table.h"
#include "string-util.h"
#include "sysctl-util.h"
static int dhcp_remove_routes(Link *link, sd_dhcp_lease *lease, sd_dhcp_lease *new_lease, struct in_addr *address);
static int dhcp_remove_router(Link *link, sd_dhcp_lease *lease, struct in_addr *address);
static int dhcp_remove_address(Link *link, sd_dhcp_lease *lease, struct in_addr *address);
void dhcp4_release_old_lease(Link *link) {
union in_addr_union address = IN_ADDR_NULL, address_old = IN_ADDR_NULL;
assert(link);
if (!link->dhcp_lease_old)
return;
assert(link->dhcp_lease);
(void) sd_dhcp_lease_get_address(link->dhcp_lease_old, &address_old.in);
(void) sd_dhcp_lease_get_address(link->dhcp_lease, &address.in);
(void) dhcp_remove_routes(link, link->dhcp_lease_old, link->dhcp_lease, &address_old.in);
if (!in_addr_equal(AF_INET, &address_old, &address)) {
(void) dhcp_remove_router(link, link->dhcp_lease_old, &address_old.in);
(void) dhcp_remove_address(link, link->dhcp_lease_old, &address_old.in);
}
link->dhcp_lease_old = sd_dhcp_lease_unref(link->dhcp_lease_old);
link_dirty(link);
}
static int dhcp4_route_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
int r;
assert(link);
assert(link->dhcp4_messages > 0);
link->dhcp4_messages--;
if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
return 1;
r = sd_netlink_message_get_errno(m);
if (r < 0 && r != -EEXIST) {
log_link_error_errno(link, r, "Could not set DHCPv4 route: %m");
link_enter_failed(link);
return 1;
}
if (link->dhcp4_messages == 0) {
link->dhcp4_configured = true;
/* New address and routes are configured now. Let's release old lease. */
dhcp4_release_old_lease(link);
link_check_ready(link);
}
return 1;
}
static int route_scope_from_address(const Route *route, const struct in_addr *self_addr) {
assert(route);
assert(self_addr);
if (in4_addr_is_localhost(&route->dst.in) ||
(!in4_addr_is_null(self_addr) && in4_addr_equal(&route->dst.in, self_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 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);
if (IN_SET(route->scope, RT_SCOPE_LINK, RT_SCOPE_UNIVERSE))
route->prefsrc.in = address;
r = route_configure(route, link, dhcp4_route_handler);
if (r < 0)
return log_link_error_errno(link, r, "Could not set host route: %m");
if (r > 0)
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_error_errno(link, r, "Could not set host route: %m");
if (r > 0)
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)
return log_link_error_errno(link, r, "Could not set routes: %m");
if (r > 0)
link->dhcp4_messages++;
}
return 0;
}
static bool route_present_in_routes(const Route *route, sd_dhcp_route **routes, unsigned n_routes) {
assert(n_routes == 0 || routes);
for (unsigned j = 0; j < n_routes; j++) {
union in_addr_union a;
unsigned char l;
assert_se(sd_dhcp_route_get_gateway(routes[j], &a.in) >= 0);
if (!in_addr_equal(AF_INET, &a, &route->gw))
continue;
assert_se(sd_dhcp_route_get_destination(routes[j], &a.in) >= 0);
if (!in_addr_equal(AF_INET, &a, &route->dst))
continue;
assert_se(sd_dhcp_route_get_destination_prefix_length(routes[j], &l) >= 0);
if (l != route->dst_prefixlen)
continue;
return true;
}
return false;
}
static int dhcp_remove_routes(Link *link, sd_dhcp_lease *lease, sd_dhcp_lease *new_lease, struct in_addr *address) {
_cleanup_free_ sd_dhcp_route **routes = NULL, **new_routes = NULL;
uint32_t table;
int m = 0, n, i, r;
assert(link);
assert(address);
if (!link->network->dhcp_use_routes)
return 0;
n = sd_dhcp_lease_get_routes(lease, &routes);
if (IN_SET(n, 0, -ENODATA))
return 0;
else if (n < 0)
return log_link_error_errno(link, n, "DHCP error: Failed to get routes: %m");
if (new_lease) {
m = sd_dhcp_lease_get_routes(new_lease, &new_routes);
if (m == -ENODATA)
m = 0;
else if (m < 0)
return log_link_error_errno(link, m, "DHCP error: Failed to get routes: %m");
}
table = link_get_dhcp_route_table(link);
for (i = 0; i < n; i++) {
_cleanup_(route_freep) Route *route = NULL;
r = route_new(&route);
if (r < 0)
return log_oom();
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->priority = link->network->dhcp_route_metric;
route->table = table;
route->scope = route_scope_from_address(route, address);
if (IN_SET(route->scope, RT_SCOPE_LINK, RT_SCOPE_UNIVERSE))
route->prefsrc.in = *address;
if (route_present_in_routes(route, new_routes, m))
continue;
(void) route_remove(route, link, NULL);
}
return n;
}
static int dhcp_remove_router(Link *link, sd_dhcp_lease *lease, struct in_addr *address) {
_cleanup_(route_freep) Route *route_gw = NULL, *route = NULL;
const struct in_addr *router;
uint32_t table;
int r;
assert(link);
assert(address);
if (!link->network->dhcp_use_routes)
return 0;
r = sd_dhcp_lease_get_router(lease, &router);
if (IN_SET(r, 0, -ENODATA)) {
log_link_debug(link, "DHCP: No gateway received from DHCP server.");
return 0;
} else if (r < 0)
return log_link_error_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, ignoring.");
return 0;
}
table = link_get_dhcp_route_table(link);
r = route_new(&route_gw);
if (r < 0)
return log_oom();
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;
(void) route_remove(route_gw, link, NULL);
r = route_new(&route);
if (r < 0)
return log_oom();
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;
(void) route_remove(route, link, NULL);
return 0;
}
static int dhcp_remove_address(Link *link, sd_dhcp_lease *lease, struct in_addr *address) {
_cleanup_(address_freep) Address *a = NULL;
struct in_addr netmask;
int r;
assert(link);
assert(address);
if (in4_addr_is_null(address))
return 0;
r = address_new(&a);
if (r < 0)
return log_oom();
a->family = AF_INET;
a->in_addr.in = *address;
if (sd_dhcp_lease_get_netmask(lease, &netmask) >= 0)
a->prefixlen = in4_addr_netmask_to_prefixlen(&netmask);
(void) address_remove(a, link, NULL);
return 0;
}
static int dhcp_reset_mtu(Link *link) {
uint16_t mtu;
int r;
assert(link);
if (!link->network->dhcp_use_mtu)
return 0;
r = sd_dhcp_lease_get_mtu(link->dhcp_lease, &mtu);
if (r < 0)
return r;
if (link->original_mtu == mtu)
return 0;
r = link_set_mtu(link, link->original_mtu);
if (r < 0) {
log_link_error_errno(link, r, "DHCP error: could not reset MTU: %m");
link_enter_failed(link);
return r;
}
return 0;
}
static int dhcp_reset_hostname(Link *link) {
const char *hostname;
int r;
assert(link);
if (!link->network->dhcp_use_hostname)
return 0;
hostname = link->network->dhcp_hostname;
if (!hostname)
(void) sd_dhcp_lease_get_hostname(link->dhcp_lease, &hostname);
if (!hostname)
return 0;
/* If a hostname was set due to the lease, then unset it now. */
r = manager_set_hostname(link->manager, NULL);
if (r < 0)
return log_link_error_errno(link, r, "DHCP error: Failed to reset transient hostname: %m");
return 0;
}
static int dhcp_lease_lost(Link *link) {
struct in_addr address = {};
assert(link);
assert(link->dhcp_lease);
log_link_warning(link, "DHCP lease lost");
link->dhcp4_configured = false;
(void) sd_dhcp_lease_get_address(link->dhcp_lease, &address);
(void) dhcp_remove_routes(link, link->dhcp_lease, NULL, &address);
(void) dhcp_remove_router(link, link->dhcp_lease, &address);
(void) dhcp_remove_address(link, link->dhcp_lease, &address);
(void) dhcp_reset_mtu(link);
(void) dhcp_reset_hostname(link);
link->dhcp_lease = sd_dhcp_lease_unref(link->dhcp_lease);
link_dirty(link);
return 0;
}
static int dhcp4_address_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
int r;
assert(link);
if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
return 1;
r = sd_netlink_message_get_errno(m);
if (r < 0 && r != -EEXIST) {
log_link_error_errno(link, r, "Could not set DHCPv4 address: %m");
link_enter_failed(link);
return 1;
} else if (r >= 0)
(void) manager_rtnl_process_address(rtnl, m, link->manager);
r = link_set_dhcp_routes(link);
if (r < 0) {
link_enter_failed(link);
return 1;
}
/* Add back static routes since kernel removes while DHCPv4 address is removed from when lease expires */
r = link_request_set_routes(link);
if (r < 0) {
link_enter_failed(link);
return 1;
}
if (link->dhcp4_messages == 0) {
link->dhcp4_configured = true;
/* The new address is configured, and no route is requested.
* Let's drop the old lease. */
dhcp4_release_old_lease(link);
link_check_ready(link);
}
return 1;
}
static int dhcp4_update_address(Link *link,
struct in_addr *address,
struct in_addr *netmask,
uint32_t lifetime) {
_cleanup_(address_freep) Address *addr = NULL;
unsigned prefixlen;
int r;
assert(address);
assert(netmask);
assert(lifetime);
prefixlen = in4_addr_netmask_to_prefixlen(netmask);
r = address_new(&addr);
if (r < 0)
return r;
addr->family = AF_INET;
addr->in_addr.in.s_addr = address->s_addr;
addr->cinfo.ifa_prefered = lifetime;
addr->cinfo.ifa_valid = lifetime;
addr->prefixlen = prefixlen;
addr->broadcast.s_addr = address->s_addr | ~netmask->s_addr;
/* allow reusing an existing address and simply update its lifetime
* in case it already exists */
r = address_configure(addr, link, dhcp4_address_handler, true);
if (r < 0)
return r;
return 0;
}
static int dhcp_lease_renew(sd_dhcp_client *client, Link *link) {
sd_dhcp_lease *lease;
struct in_addr address;
struct in_addr netmask;
uint32_t lifetime = CACHE_INFO_INFINITY_LIFE_TIME;
int r;
assert(link);
assert(client);
assert(link->network);
r = sd_dhcp_client_get_lease(client, &lease);
if (r < 0)
return log_link_warning_errno(link, r, "DHCP error: no lease: %m");
sd_dhcp_lease_unref(link->dhcp_lease);
link->dhcp4_configured = false;
link->dhcp_lease = sd_dhcp_lease_ref(lease);
link_dirty(link);
r = sd_dhcp_lease_get_address(lease, &address);
if (r < 0)
return log_link_warning_errno(link, r, "DHCP error: no address: %m");
r = sd_dhcp_lease_get_netmask(lease, &netmask);
if (r < 0)
return log_link_warning_errno(link, r, "DHCP error: no netmask: %m");
if (!FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_DHCP)) {
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)
return log_link_warning_errno(link, r, "Could not update IP address: %m");
return 0;
}
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);
link->dhcp4_configured = false;
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);
if (!FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_DHCP)) {
r = sd_dhcp_lease_get_lifetime(lease, &lifetime);
if (r < 0)
return log_link_warning_errno(link, r, "DHCP error: no lifetime: %m");
}
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);
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);
}
}
r = dhcp4_update_address(link, &address, &netmask, lifetime);
if (r < 0)
return log_link_warning_errno(link, r, "Could not update IP address: %m");
return 0;
}
static int dhcp_lease_ip_change(sd_dhcp_client *client, Link *link) {
int r;
link->dhcp_lease_old = TAKE_PTR(link->dhcp_lease);
/* On ip address change, to keep the connectability, we would like to assign new address and
* routes, and then release old lease. There are two possible success paths:
*
* 1. new address and routes are configured.
* -> handled by dhcp_release_old_lease() in dhcp4_route_handler().
* 2. new address is configured and no route is requested.
* -> handled by dhcp_release_old_lease() in dhcp4_address_handler().
*
* On error in assigning new address and routes, then the link always enters to the failed
* state. And link_enter_failed() leads to the DHCP client to be stopped. So,
* dhcp_release_old_lease() will be also called by link_stop_clients().
*/
r = dhcp_lease_acquired(client, link);
if (r < 0) {
/* If it fails, then the new address is not configured yet.
* So, let's simply drop the old lease. */
sd_dhcp_lease_unref(link->dhcp_lease);
link->dhcp_lease = TAKE_PTR(link->dhcp_lease_old);
(void) dhcp_lease_lost(link);
return r;
}
return 0;
}
static int dhcp_server_is_black_listed(Link *link, sd_dhcp_client *client) {
sd_dhcp_lease *lease;
struct in_addr addr;
int r;
assert(link);
assert(link->network);
assert(client);
r = sd_dhcp_client_get_lease(client, &lease);
if (r < 0)
return log_link_error_errno(link, r, "Failed to get DHCP lease: %m");
r = sd_dhcp_lease_get_server_identifier(lease, &addr);
if (r < 0)
return log_link_debug_errno(link, r, "Failed to get DHCP server ip address: %m");
if (set_contains(link->network->dhcp_black_listed_ip, UINT32_TO_PTR(addr.s_addr))) {
log_struct(LOG_DEBUG,
LOG_LINK_INTERFACE(link),
LOG_LINK_MESSAGE(link, "DHCPv4 ip '%u.%u.%u.%u' found in black listed ip addresses, ignoring offer",
ADDRESS_FMT_VAL(addr)));
return true;
}
return false;
}
static int dhcp4_handler(sd_dhcp_client *client, int event, void *userdata) {
Link *link = userdata;
int r;
assert(link);
assert(link->network);
assert(link->manager);
if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
return 0;
switch (event) {
case SD_DHCP_CLIENT_EVENT_STOP:
if (link_ipv4ll_enabled(link, ADDRESS_FAMILY_FALLBACK_IPV4)) {
assert(link->ipv4ll);
log_link_debug(link, "DHCP client is stopped. Acquiring IPv4 link-local address");
r = sd_ipv4ll_start(link->ipv4ll);
if (r < 0)
return log_link_warning_errno(link, r, "Could not acquire IPv4 link-local address: %m");
}
if (FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_DHCP)) {
log_link_notice(link, "DHCPv4 connection considered critical, ignoring request to reconfigure it.");
return 0;
}
if (link->network->dhcp_send_release)
(void) sd_dhcp_client_send_release(client);
if (link->dhcp_lease) {
r = dhcp_lease_lost(link);
if (r < 0) {
link_enter_failed(link);
return r;
}
}
break;
case SD_DHCP_CLIENT_EVENT_EXPIRED:
if (FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_DHCP)) {
log_link_notice(link, "DHCPv4 connection considered critical, ignoring request to reconfigure it.");
return 0;
}
if (link->dhcp_lease) {
r = dhcp_lease_lost(link);
if (r < 0) {
link_enter_failed(link);
return r;
}
}
break;
case SD_DHCP_CLIENT_EVENT_IP_CHANGE:
if (FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_DHCP)) {
log_link_notice(link, "DHCPv4 connection considered critical, ignoring request to reconfigure it.");
return 0;
}
r = dhcp_lease_ip_change(client, link);
if (r < 0) {
link_enter_failed(link);
return r;
}
break;
case SD_DHCP_CLIENT_EVENT_RENEW:
r = dhcp_lease_renew(client, link);
if (r < 0) {
link_enter_failed(link);
return r;
}
break;
case SD_DHCP_CLIENT_EVENT_IP_ACQUIRE:
r = dhcp_lease_acquired(client, link);
if (r < 0) {
link_enter_failed(link);
return r;
}
break;
case SD_DHCP_CLIENT_EVENT_SELECTING:
r = dhcp_server_is_black_listed(link, client);
if (r < 0)
return r;
if (r != 0)
return -ENOMSG;
break;
default:
if (event < 0)
log_link_warning_errno(link, event, "DHCP error: Client failed: %m");
else
log_link_warning(link, "DHCP unknown event: %i", event);
break;
}
return 0;
}
static int dhcp4_set_hostname(Link *link) {
_cleanup_free_ char *hostname = NULL;
const char *hn;
int r;
assert(link);
if (!link->network->dhcp_send_hostname)
hn = NULL;
else if (link->network->dhcp_hostname)
hn = link->network->dhcp_hostname;
else {
r = gethostname_strict(&hostname);
if (r < 0 && r != -ENXIO) /* ENXIO: no hostname set or hostname is "localhost" */
return r;
hn = hostname;
}
r = sd_dhcp_client_set_hostname(link->dhcp_client, hn);
if (r == -EINVAL && hostname)
/* Ignore error when the machine's hostname is not suitable to send in DHCP packet. */
log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to set hostname from kernel hostname, ignoring: %m");
else if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set hostname: %m");
return 0;
}
static bool promote_secondaries_enabled(const char *ifname) {
_cleanup_free_ char *promote_secondaries_sysctl = NULL;
char *promote_secondaries_path;
int r;
promote_secondaries_path = strjoina("net/ipv4/conf/", ifname, "/promote_secondaries");
r = sysctl_read(promote_secondaries_path, &promote_secondaries_sysctl);
if (r < 0) {
log_debug_errno(r, "Cannot read sysctl %s", promote_secondaries_path);
return false;
}
truncate_nl(promote_secondaries_sysctl);
r = parse_boolean(promote_secondaries_sysctl);
if (r < 0)
log_warning_errno(r, "Cannot parse sysctl %s with content %s as boolean", promote_secondaries_path, promote_secondaries_sysctl);
return r > 0;
}
/* dhcp4_set_promote_secondaries will ensure this interface has
* the "promote_secondaries" option in the kernel set. If this sysctl
* is not set DHCP will work only as long as the IP address does not
* changes between leases. The kernel will remove all secondary IP
* addresses of an interface otherwise. The way systemd-network works
* is that the new IP of a lease is added as a secondary IP and when
* the primary one expires it relies on the kernel to promote the
* secondary IP. See also https://github.com/systemd/systemd/issues/7163
*/
int dhcp4_set_promote_secondaries(Link *link) {
int r;
assert(link);
assert(link->network);
assert(link->network->dhcp & ADDRESS_FAMILY_IPV4);
/* check if the kernel has promote_secondaries enabled for our
* interface. If it is not globally enabled or enabled for the
* specific interface we must either enable it.
*/
if (!(promote_secondaries_enabled("all") || promote_secondaries_enabled(link->ifname))) {
char *promote_secondaries_path = NULL;
log_link_debug(link, "promote_secondaries is unset, setting it");
promote_secondaries_path = strjoina("net/ipv4/conf/", link->ifname, "/promote_secondaries");
r = sysctl_write(promote_secondaries_path, "1");
if (r < 0)
log_link_warning_errno(link, r, "cannot set sysctl %s to 1", promote_secondaries_path);
return r > 0;
}
return 0;
}
int dhcp4_set_client_identifier(Link *link) {
int r;
assert(link);
assert(link->network);
assert(link->dhcp_client);
switch (link->network->dhcp_client_identifier) {
case DHCP_CLIENT_ID_DUID: {
/* If configured, apply user specified DUID and IAID */
const DUID *duid = link_get_duid(link);
if (duid->type == DUID_TYPE_LLT && duid->raw_data_len == 0)
r = sd_dhcp_client_set_iaid_duid_llt(link->dhcp_client,
link->network->iaid_set,
link->network->iaid,
duid->llt_time);
else
r = sd_dhcp_client_set_iaid_duid(link->dhcp_client,
link->network->iaid_set,
link->network->iaid,
duid->type,
duid->raw_data_len > 0 ? duid->raw_data : NULL,
duid->raw_data_len);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set IAID+DUID: %m");
break;
}
case DHCP_CLIENT_ID_DUID_ONLY: {
/* If configured, apply user specified DUID */
const DUID *duid = link_get_duid(link);
if (duid->type == DUID_TYPE_LLT && duid->raw_data_len == 0)
r = sd_dhcp_client_set_duid_llt(link->dhcp_client,
duid->llt_time);
else
r = sd_dhcp_client_set_duid(link->dhcp_client,
duid->type,
duid->raw_data_len > 0 ? duid->raw_data : NULL,
duid->raw_data_len);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set DUID: %m");
break;
}
case DHCP_CLIENT_ID_MAC:
r = sd_dhcp_client_set_client_id(link->dhcp_client,
ARPHRD_ETHER,
(const uint8_t *) &link->mac,
sizeof(link->mac));
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set client ID: %m");
break;
default:
assert_not_reached("Unknown client identifier type.");
}
return 0;
}
int dhcp4_configure(Link *link) {
int r;
assert(link);
assert(link->network);
assert(link->network->dhcp & ADDRESS_FAMILY_IPV4);
if (!link->dhcp_client) {
r = sd_dhcp_client_new(&link->dhcp_client, link->network->dhcp_anonymize);
if (r == -ENOMEM)
return log_oom();
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to create DHCP4 client: %m");
}
r = sd_dhcp_client_attach_event(link->dhcp_client, NULL, 0);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to attach event: %m");
r = sd_dhcp_client_set_mac(link->dhcp_client,
(const uint8_t *) &link->mac,
sizeof (link->mac), ARPHRD_ETHER);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set MAC address: %m");
r = sd_dhcp_client_set_ifindex(link->dhcp_client, link->ifindex);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set ifindex: %m");
r = sd_dhcp_client_set_callback(link->dhcp_client, dhcp4_handler, link);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set callback: %m");
r = sd_dhcp_client_set_request_broadcast(link->dhcp_client,
link->network->dhcp_broadcast);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for broadcast: %m");
if (link->mtu) {
r = sd_dhcp_client_set_mtu(link->dhcp_client, link->mtu);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set MTU: %m");
}
if (link->network->dhcp_use_mtu) {
r = sd_dhcp_client_set_request_option(link->dhcp_client,
SD_DHCP_OPTION_INTERFACE_MTU);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for MTU: %m");
}
/* NOTE: even if this variable is called "use", it also "sends" PRL
* options, maybe there should be a different configuration variable
* to send or not route options?. */
/* NOTE: when using Anonymize=yes, routes PRL options are sent
* by default, so they don't need to be added here. */
if (link->network->dhcp_use_routes && !link->network->dhcp_anonymize) {
r = sd_dhcp_client_set_request_option(link->dhcp_client,
SD_DHCP_OPTION_STATIC_ROUTE);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for static route: %m");
r = sd_dhcp_client_set_request_option(link->dhcp_client,
SD_DHCP_OPTION_CLASSLESS_STATIC_ROUTE);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for classless static route: %m");
}
if (link->network->dhcp_use_domains != DHCP_USE_DOMAINS_NO && !link->network->dhcp_anonymize) {
r = sd_dhcp_client_set_request_option(link->dhcp_client, SD_DHCP_OPTION_DOMAIN_SEARCH_LIST);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for domain search list: %m");
}
if (link->network->dhcp_use_ntp) {
r = sd_dhcp_client_set_request_option(link->dhcp_client, SD_DHCP_OPTION_NTP_SERVER);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for NTP server: %m");
}
if (link->network->dhcp_use_timezone) {
r = sd_dhcp_client_set_request_option(link->dhcp_client, SD_DHCP_OPTION_NEW_TZDB_TIMEZONE);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for timezone: %m");
}
r = dhcp4_set_hostname(link);
if (r < 0)
return r;
if (link->network->dhcp_vendor_class_identifier) {
r = sd_dhcp_client_set_vendor_class_identifier(link->dhcp_client,
link->network->dhcp_vendor_class_identifier);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set vendor class identifier: %m");
}
if (link->network->dhcp_user_class) {
r = sd_dhcp_client_set_user_class(link->dhcp_client, (const char **) link->network->dhcp_user_class);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set user class: %m");
}
if (link->network->dhcp_client_port) {
r = sd_dhcp_client_set_client_port(link->dhcp_client, link->network->dhcp_client_port);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set listen port: %m");
}
if (link->network->dhcp_max_attempts > 0) {
r = sd_dhcp_client_set_max_attempts(link->dhcp_client, link->network->dhcp_max_attempts);
if (r < 0)
return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set max attempts: %m");
}
return dhcp4_set_client_identifier(link);
}
int config_parse_dhcp_max_attempts(
const char *unit,
const char *filename,
unsigned line,
const char *section,
unsigned section_line,
const char *lvalue,
int ltype,
const char *rvalue,
void *data,
void *userdata) {
Network *network = data;
uint64_t a;
int r;
assert(network);
assert(lvalue);
assert(rvalue);
if (isempty(rvalue)) {
network->dhcp_max_attempts = 0;
return 0;
}
if (streq(rvalue, "infinity")) {
network->dhcp_max_attempts = (uint64_t) -1;
return 0;
}
r = safe_atou64(rvalue, &a);
if (r < 0) {
log_syntax(unit, LOG_ERR, filename, line, r,
"Failed to parse DHCP maximum attempts, ignoring: %s", rvalue);
return 0;
}
if (a == 0) {
log_syntax(unit, LOG_ERR, filename, line, 0,
"%s= must be positive integer or 'infinity', ignoring: %s", lvalue, rvalue);
return 0;
}
network->dhcp_max_attempts = a;
return 0;
}
int config_parse_dhcp_black_listed_ip_address(
const char *unit,
const char *filename,
unsigned line,
const char *section,
unsigned section_line,
const char *lvalue,
int ltype,
const char *rvalue,
void *data,
void *userdata) {
Network *network = data;
const char *p;
int r;
assert(filename);
assert(lvalue);
assert(rvalue);
assert(data);
if (isempty(rvalue)) {
network->dhcp_black_listed_ip = set_free(network->dhcp_black_listed_ip);
return 0;
}
for (p = rvalue;;) {
_cleanup_free_ char *n = NULL;
union in_addr_union ip;
r = extract_first_word(&p, &n, NULL, 0);
if (r < 0) {
log_syntax(unit, LOG_ERR, filename, line, r,
"Failed to parse DHCP black listed ip address, ignoring assignment: %s",
rvalue);
return 0;
}
if (r == 0)
return 0;
r = in_addr_from_string(AF_INET, n, &ip);
if (r < 0) {
log_syntax(unit, LOG_ERR, filename, line, r,
"DHCP black listed ip address is invalid, ignoring assignment: %s", n);
continue;
}
r = set_ensure_allocated(&network->dhcp_black_listed_ip, NULL);
if (r < 0)
return log_oom();
r = set_put(network->dhcp_black_listed_ip, UINT32_TO_PTR(ip.in.s_addr));
if (r < 0)
log_syntax(unit, LOG_ERR, filename, line, r,
"Failed to store DHCP black listed ip address '%s', ignoring assignment: %m", n);
}
return 0;
}
int config_parse_dhcp_user_class(
const char *unit,
const char *filename,
unsigned line,
const char *section,
unsigned section_line,
const char *lvalue,
int ltype,
const char *rvalue,
void *data,
void *userdata) {
char ***l = data;
int r;
assert(l);
assert(lvalue);
assert(rvalue);
if (isempty(rvalue)) {
*l = strv_free(*l);
return 0;
}
for (;;) {
_cleanup_free_ char *w = NULL;
r = extract_first_word(&rvalue, &w, NULL, 0);
if (r == -ENOMEM)
return log_oom();
if (r < 0) {
log_syntax(unit, LOG_ERR, filename, line, r,
"Failed to split user classes option, ignoring: %s", rvalue);
break;
}
if (r == 0)
break;
if (strlen(w) > 255) {
log_syntax(unit, LOG_ERR, filename, line, 0,
"%s length is not in the range 1-255, ignoring.", w);
continue;
}
r = strv_push(l, w);
if (r < 0)
return log_oom();
w = NULL;
}
return 0;
}
static const char* const dhcp_client_identifier_table[_DHCP_CLIENT_ID_MAX] = {
[DHCP_CLIENT_ID_MAC] = "mac",
[DHCP_CLIENT_ID_DUID] = "duid",
[DHCP_CLIENT_ID_DUID_ONLY] = "duid-only",
};
DEFINE_PRIVATE_STRING_TABLE_LOOKUP_FROM_STRING(dhcp_client_identifier, DHCPClientIdentifier);
DEFINE_CONFIG_PARSE_ENUM(config_parse_dhcp_client_identifier, dhcp_client_identifier, DHCPClientIdentifier,
"Failed to parse client identifier type");
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