/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include #include #include #include #include "escape.h" #include "alloc-util.h" #include "dhcp-client-internal.h" #include "hostname-util.h" #include "parse-util.h" #include "network-internal.h" #include "networkd-address.h" #include "networkd-dhcp4.h" #include "networkd-link.h" #include "networkd-manager.h" #include "networkd-network.h" #include "string-table.h" #include "strv.h" #include "sysctl-util.h" #include "web-util.h" static int dhcp4_update_address(Link *link, bool announce); static int dhcp4_remove_all(Link *link); static int dhcp4_release_old_lease(Link *link) { Route *route; int k, r = 0; assert(link); if (!link->dhcp_address_old && set_isempty(link->dhcp_routes_old)) return 0; log_link_debug(link, "Removing old DHCPv4 address and routes."); link_dirty(link); SET_FOREACH(route, link->dhcp_routes_old) { k = route_remove(route, NULL, link, NULL); if (k < 0) r = k; } if (link->dhcp_address_old) { k = address_remove(link->dhcp_address_old, link, NULL); if (k < 0) r = k; } return r; } static void dhcp4_check_ready(Link *link) { int r; if (link->network->dhcp_send_decline && !link->dhcp4_address_bind) return; if (link->dhcp4_messages > 0) return; link->dhcp4_configured = true; /* New address and routes are configured now. Let's release old lease. */ r = dhcp4_release_old_lease(link); if (r < 0) { link_enter_failed(link); return; } r = sd_ipv4ll_stop(link->ipv4ll); if (r < 0) log_link_warning_errno(link, r, "Failed to drop IPv4 link-local address, ignoring: %m"); link_check_ready(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 == -ENETUNREACH && !link->dhcp4_route_retrying) { /* It seems kernel does not support that the prefix route cannot be configured with * route table. Let's once drop the config and reconfigure them later. */ log_link_message_debug_errno(link, m, r, "Could not set DHCPv4 route, retrying later"); link->dhcp4_route_failed = true; link->manager->dhcp4_prefix_root_cannot_set_table = true; } else if (r < 0 && r != -EEXIST) { log_link_message_warning_errno(link, m, r, "Could not set DHCPv4 route"); link_enter_failed(link); return 1; } if (link->dhcp4_messages == 0 && link->dhcp4_route_failed) { link->dhcp4_route_failed = false; link->dhcp4_route_retrying = true; r = dhcp4_remove_all(link); if (r < 0) link_enter_failed(link); return 1; } dhcp4_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 bool link_prefixroute(Link *link) { return !link->network->dhcp_route_table_set || link->network->dhcp_route_table == RT_TABLE_MAIN || link->manager->dhcp4_prefix_root_cannot_set_table; } static int dhcp_route_configure(Route *route, Link *link) { Route *ret; int r; assert(route); assert(link); r = route_configure(route, link, dhcp4_route_handler, &ret); if (r < 0) return log_link_error_errno(link, r, "Failed to set DHCPv4 route: %m"); link->dhcp4_messages++; r = set_ensure_put(&link->dhcp_routes, &route_hash_ops, ret); if (r < 0) return log_link_error_errno(link, r, "Failed to store DHCPv4 route: %m"); (void) set_remove(link->dhcp_routes_old, ret); return 0; } static int link_set_dns_routes(Link *link, const struct in_addr *address) { const struct in_addr *dns; uint32_t table; int i, n, r; assert(link); assert(link->dhcp_lease); assert(link->network); if (!link->network->dhcp_use_dns || !link->network->dhcp_routes_to_dns) return 0; n = sd_dhcp_lease_get_dns(link->dhcp_lease, &dns); if (IN_SET(n, 0, -ENODATA)) return 0; if (n < 0) return log_link_warning_errno(link, n, "DHCP error: could not get DNS servers: %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_link_error_errno(link, r, "Could not allocate route: %m"); /* Set routes to DNS servers. */ route->family = AF_INET; route->dst.in = dns[i]; route->dst_prefixlen = 32; route->prefsrc.in = *address; route->scope = RT_SCOPE_LINK; route->protocol = RTPROT_DHCP; route->priority = link->network->dhcp_route_metric; route->table = table; r = dhcp_route_configure(route, link); if (r < 0) return log_link_error_errno(link, r, "Could not set route to DNS server: %m"); } return 0; } static int dhcp_prefix_route_from_lease( const sd_dhcp_lease *lease, uint32_t table, const struct in_addr *address, Route **ret_route) { Route *route; struct in_addr netmask; int r; r = sd_dhcp_lease_get_netmask((sd_dhcp_lease*) lease, &netmask); if (r < 0) return r; r = route_new(&route); if (r < 0) return r; route->family = AF_INET; route->dst.in.s_addr = address->s_addr & netmask.s_addr; route->dst_prefixlen = in4_addr_netmask_to_prefixlen(&netmask); route->prefsrc.in = *address; route->scope = RT_SCOPE_LINK; route->protocol = RTPROT_DHCP; route->table = table; *ret_route = route; 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; struct in_addr address; uint32_t table; Route *rt; int r, n; 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_has_carrier(link) && !link->network->configure_without_carrier) /* During configuring addresses, the link lost its carrier. As networkd is dropping * the addresses now, let's not configure the routes either. */ return 0; while ((rt = set_steal_first(link->dhcp_routes))) { r = set_ensure_put(&link->dhcp_routes_old, &route_hash_ops, rt); if (r < 0) return log_link_error_errno(link, r, "Failed to store old DHCPv4 route: %m"); } 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"); if (!link_prefixroute(link)) { _cleanup_(route_freep) Route *prefix_route = NULL; r = dhcp_prefix_route_from_lease(link->dhcp_lease, table, &address, &prefix_route); if (r < 0) return log_link_error_errno(link, r, "Could not create prefix route: %m"); r = dhcp_route_configure(prefix_route, link); if (r < 0) return log_link_error_errno(link, r, "Could not set prefix route: %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) return log_link_error_errno(link, n, "DHCP: could not get routes: %m"); for (int 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; } } if (link->network->dhcp_use_routes) { /* 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 && static_route) log_link_warning(link, "Classless static routes received from DHCP server: ignoring static-route option"); for (int i = 0; i < n; i++) { _cleanup_(route_freep) Route *route = NULL; 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; route->gw_family = AF_INET; 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->mtu = link->network->dhcp_route_mtu; route->scope = route_scope_from_address(route, &address); if (IN_SET(route->scope, RT_SCOPE_LINK, RT_SCOPE_UNIVERSE)) route->prefsrc.in = address; if (set_contains(link->dhcp_routes, route)) continue; r = dhcp_route_configure(route, link); if (r < 0) return log_link_error_errno(link, r, "Could not set route: %m"); } } if (link->network->dhcp_use_gateway) { const struct in_addr *router; 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) 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."); else if (classless_route) /* 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. */ log_link_warning(link, "Classless static routes received from DHCP server: ignoring router option"); else { _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; route_gw->mtu = link->network->dhcp_route_mtu; r = dhcp_route_configure(route_gw, link); if (r < 0) return log_link_error_errno(link, r, "Could not set host route: %m"); 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_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; route->mtu = link->network->dhcp_route_mtu; r = dhcp_route_configure(route, link); if (r < 0) return log_link_error_errno(link, r, "Could not set router: %m"); HASHMAP_FOREACH(rt, link->network->routes_by_section) { if (!rt->gateway_from_dhcp_or_ra) continue; if (rt->gw_family != AF_INET) continue; rt->gw.in = router[0]; if (!rt->protocol_set) rt->protocol = RTPROT_DHCP; if (!rt->priority_set) rt->priority = link->network->dhcp_route_metric; if (!rt->table_set) rt->table = table; if (rt->mtu == 0) rt->mtu = link->network->dhcp_route_mtu; r = dhcp_route_configure(rt, link); if (r < 0) return log_link_error_errno(link, r, "Could not set gateway: %m"); } } } return link_set_dns_routes(link, &address); } 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 == -ENODATA) return 0; if (r < 0) return log_link_error_errno(link, r, "DHCP error: failed to get MTU from lease: %m"); if (link->original_mtu == mtu) return 0; r = link_set_mtu(link, link->original_mtu); if (r < 0) return log_link_error_errno(link, r, "DHCP error: could not reset MTU: %m"); 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 dhcp4_remove_route_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) { int r; assert(m); assert(link); assert(link->dhcp4_remove_messages > 0); link->dhcp4_remove_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 != -ESRCH) log_link_message_warning_errno(link, m, r, "Failed to remove DHCPv4 route, ignoring"); if (link->dhcp4_remove_messages == 0) { r = dhcp4_update_address(link, false); if (r < 0) link_enter_failed(link); } return 1; } static int dhcp4_remove_address_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) { int r; assert(m); assert(link); assert(link->dhcp4_remove_messages > 0); link->dhcp4_remove_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 != -EADDRNOTAVAIL) log_link_message_warning_errno(link, m, r, "Failed to remove DHCPv4 address, ignoring"); else (void) manager_rtnl_process_address(rtnl, m, link->manager); if (link->dhcp4_remove_messages == 0) { r = dhcp4_update_address(link, false); if (r < 0) link_enter_failed(link); } return 1; } static int dhcp4_remove_all(Link *link) { Route *route; int k, r = 0; assert(link); SET_FOREACH(route, link->dhcp_routes) { k = route_remove(route, NULL, link, dhcp4_remove_route_handler); if (k < 0) r = k; else link->dhcp4_remove_messages++; } if (link->dhcp_address) { k = address_remove(link->dhcp_address, link, dhcp4_remove_address_handler); if (k < 0) r = k; else link->dhcp4_remove_messages++; } return r; } static int dhcp_lease_lost(Link *link) { int k, r = 0; assert(link); assert(link->dhcp_lease); log_link_info(link, "DHCP lease lost"); link->dhcp4_configured = false; /* dhcp_lease_lost() may be called during renewing IP address. */ k = dhcp4_release_old_lease(link); if (k < 0) r = k; k = dhcp4_remove_all(link); if (k < 0) r = k; k = dhcp_reset_mtu(link); if (k < 0) r = k; k = dhcp_reset_hostname(link); if (k < 0) r = k; link->dhcp_lease = sd_dhcp_lease_unref(link->dhcp_lease); link_dirty(link); (void) sd_ipv4acd_stop(link->dhcp_acd); return r; } static void dhcp_address_on_acd(sd_ipv4acd *acd, int event, void *userdata) { _cleanup_free_ char *pretty = NULL; union in_addr_union address = {}; Link *link; int r; assert(acd); assert(userdata); link = userdata; switch (event) { case SD_IPV4ACD_EVENT_STOP: log_link_debug(link, "Stopping ACD client for DHCP4..."); return; case SD_IPV4ACD_EVENT_BIND: if (DEBUG_LOGGING) { (void) sd_dhcp_lease_get_address(link->dhcp_lease, &address.in); (void) in_addr_to_string(AF_INET, &address, &pretty); log_link_debug(link, "Successfully claimed DHCP4 address %s", strna(pretty)); } link->dhcp4_address_bind = true; dhcp4_check_ready(link); break; case SD_IPV4ACD_EVENT_CONFLICT: (void) sd_dhcp_lease_get_address(link->dhcp_lease, &address.in); (void) in_addr_to_string(AF_INET, &address, &pretty); log_link_warning(link, "DAD conflict. Dropping DHCP4 address %s", strna(pretty)); r = sd_dhcp_client_send_decline(link->dhcp_client); if (r < 0) log_link_warning_errno(link, r, "Failed to send DHCP DECLINE, ignoring: %m"); if (link->dhcp_lease) { r = dhcp_lease_lost(link); if (r < 0) link_enter_failed(link); } break; default: assert_not_reached("Invalid IPv4ACD event."); } (void) sd_ipv4acd_stop(acd); return; } static int dhcp4_configure_dad(Link *link) { int r; assert(link); assert(link->manager); assert(link->network); if (!link->network->dhcp_send_decline) return 0; if (!link->dhcp_acd) { r = sd_ipv4acd_new(&link->dhcp_acd); if (r < 0) return r; r = sd_ipv4acd_attach_event(link->dhcp_acd, link->manager->event, 0); if (r < 0) return r; } r = sd_ipv4acd_set_ifindex(link->dhcp_acd, link->ifindex); if (r < 0) return r; r = sd_ipv4acd_set_mac(link->dhcp_acd, &link->hw_addr.addr.ether); if (r < 0) return r; return 0; } static int dhcp4_dad_update_mac(Link *link) { bool running; int r; assert(link); if (!link->dhcp_acd) return 0; running = sd_ipv4acd_is_running(link->dhcp_acd); r = sd_ipv4acd_stop(link->dhcp_acd); if (r < 0) return r; r = sd_ipv4acd_set_mac(link->dhcp_acd, &link->hw_addr.addr.ether); if (r < 0) return r; if (running) { r = sd_ipv4acd_start(link->dhcp_acd, true); if (r < 0) return r; } return 0; } static int dhcp4_start_acd(Link *link) { union in_addr_union addr; struct in_addr old; int r; if (!link->network->dhcp_send_decline) return 0; if (!link->dhcp_lease) return 0; (void) sd_ipv4acd_stop(link->dhcp_acd); link->dhcp4_address_bind = false; r = sd_dhcp_lease_get_address(link->dhcp_lease, &addr.in); if (r < 0) return r; r = sd_ipv4acd_get_address(link->dhcp_acd, &old); if (r < 0) return r; r = sd_ipv4acd_set_address(link->dhcp_acd, &addr.in); if (r < 0) return r; r = sd_ipv4acd_set_callback(link->dhcp_acd, dhcp_address_on_acd, link); if (r < 0) return r; if (DEBUG_LOGGING) { _cleanup_free_ char *pretty = NULL; (void) in_addr_to_string(AF_INET, &addr, &pretty); log_link_debug(link, "Starting IPv4ACD client. Probing DHCPv4 address %s", strna(pretty)); } r = sd_ipv4acd_start(link->dhcp_acd, !in4_addr_equal(&addr.in, &old)); if (r < 0) return r; return 1; } static int dhcp4_address_ready_callback(Address *address) { Link *link; int r; assert(address); link = address->link; /* Do not call this again. */ address->callback = NULL; r = link_set_dhcp_routes(link); if (r < 0) return r; /* Reconfigure static routes as kernel may remove some routes when lease expires. */ r = link_set_routes(link); if (r < 0) return r; r = dhcp4_start_acd(link); if (r < 0) return log_link_error_errno(link, r, "Failed to start IPv4ACD for DHCP4 address: %m"); dhcp4_check_ready(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_message_warning_errno(link, m, r, "Could not set DHCPv4 address"); link_enter_failed(link); return 1; } else if (r >= 0) (void) manager_rtnl_process_address(rtnl, m, link->manager); if (address_is_ready(link->dhcp_address)) { r = dhcp4_address_ready_callback(link->dhcp_address); if (r < 0) { link_enter_failed(link); return 1; } } else link->dhcp_address->callback = dhcp4_address_ready_callback; return 1; } static int dhcp4_update_address(Link *link, bool announce) { _cleanup_(address_freep) Address *addr = NULL; uint32_t lifetime = CACHE_INFO_INFINITY_LIFE_TIME; struct in_addr address, netmask; unsigned prefixlen; Address *ret; int r; assert(link); assert(link->network); if (!link->dhcp_lease) return 0; link_set_state(link, LINK_STATE_CONFIGURING); link->dhcp4_configured = false; /* address_handler calls link_set_routes() and link_set_nexthop(). Before they are called, the * related flags must be cleared. Otherwise, the link becomes configured state before routes * are configured. */ link->static_routes_configured = false; link->static_nexthops_configured = false; r = sd_dhcp_lease_get_address(link->dhcp_lease, &address); if (r < 0) return log_link_warning_errno(link, r, "DHCP error: no address: %m"); r = sd_dhcp_lease_get_netmask(link->dhcp_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"); } prefixlen = in4_addr_netmask_to_prefixlen(&netmask); if (announce) { const struct in_addr *router; r = sd_dhcp_lease_get_router(link->dhcp_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 "IPV4_ADDRESS_FMT_STR"/%u via "IPV4_ADDRESS_FMT_STR, IPV4_ADDRESS_FMT_VAL(address), prefixlen, IPV4_ADDRESS_FMT_VAL(router[0])), "ADDRESS="IPV4_ADDRESS_FMT_STR, IPV4_ADDRESS_FMT_VAL(address), "PREFIXLEN=%u", prefixlen, "GATEWAY="IPV4_ADDRESS_FMT_STR, IPV4_ADDRESS_FMT_VAL(router[0])); else log_struct(LOG_INFO, LOG_LINK_INTERFACE(link), LOG_LINK_MESSAGE(link, "DHCPv4 address "IPV4_ADDRESS_FMT_STR"/%u", IPV4_ADDRESS_FMT_VAL(address), prefixlen), "ADDRESS="IPV4_ADDRESS_FMT_STR, IPV4_ADDRESS_FMT_VAL(address), "PREFIXLEN=%u", prefixlen); } r = address_new(&addr); if (r < 0) return log_oom(); 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; if (prefixlen <= 30) addr->broadcast.s_addr = address.s_addr | ~netmask.s_addr; SET_FLAG(addr->flags, IFA_F_NOPREFIXROUTE, !link_prefixroute(link)); /* allow reusing an existing address and simply update its lifetime * in case it already exists */ r = address_configure(addr, link, dhcp4_address_handler, true, &ret); if (r < 0) return log_link_error_errno(link, r, "Failed to set DHCPv4 address: %m"); if (!address_equal(link->dhcp_address, ret)) link->dhcp_address_old = link->dhcp_address; link->dhcp_address = ret; return 0; } static int dhcp_lease_renew(sd_dhcp_client *client, Link *link) { sd_dhcp_lease *lease; int r; assert(link); assert(client); 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->dhcp_lease = sd_dhcp_lease_ref(lease); link_dirty(link); return dhcp4_update_address(link, false); } static int dhcp_lease_acquired(sd_dhcp_client *client, Link *link) { sd_dhcp_lease *lease; 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"); sd_dhcp_lease_unref(link->dhcp_lease); 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); } } if (link->dhcp4_remove_messages == 0) { r = dhcp4_update_address(link, true); if (r < 0) return r; } else log_link_debug(link, "The link has previously assigned DHCPv4 address or routes. " "The newly assigned address and routes will set up after old ones are removed."); return 0; } static int dhcp_lease_ip_change(sd_dhcp_client *client, Link *link) { int r; r = dhcp_lease_acquired(client, link); if (r < 0) (void) dhcp_lease_lost(link); return r; } static int dhcp_server_is_deny_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_deny_listed_ip, UINT32_TO_PTR(addr.s_addr))) { log_struct(LOG_DEBUG, LOG_LINK_INTERFACE(link), LOG_LINK_MESSAGE(link, "DHCPv4 server IP address "IPV4_ADDRESS_FMT_STR" found in deny-list, ignoring offer", IPV4_ADDRESS_FMT_VAL(addr))); return true; } return false; } static int dhcp_server_is_allow_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_allow_listed_ip, UINT32_TO_PTR(addr.s_addr))) { log_struct(LOG_DEBUG, LOG_LINK_INTERFACE(link), LOG_LINK_MESSAGE(link, "DHCPv4 server IP address "IPV4_ADDRESS_FMT_STR" found in allow-list, accepting offer", IPV4_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) { 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->dhcp_lease) { if (link->network->dhcp_send_release) { r = sd_dhcp_client_send_release(client); if (r < 0) log_link_warning_errno(link, r, "Failed to send DHCP RELEASE, ignoring: %m"); } 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: if (!set_isempty(link->network->dhcp_allow_listed_ip)) { r = dhcp_server_is_allow_listed(link, client); if (r < 0) return r; if (r == 0) return -ENOMSG; } else { r = dhcp_server_is_deny_listed(link, client); if (r < 0) return r; if (r != 0) return -ENOMSG; } break; case SD_DHCP_CLIENT_EVENT_TRANSIENT_FAILURE: if (link->ipv4ll && !sd_ipv4ll_is_running(link->ipv4ll)) { log_link_debug(link, "Problems acquiring DHCP lease, 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"); } 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 log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to get hostname: %m"); 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_debug_errno(link, r, "DHCP4 CLIENT: Failed to set hostname from kernel hostname, ignoring: %m"); else if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to set hostname: %m"); return 0; } static 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_warning_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_warning_errno(link, r, "DHCP4 CLIENT: Failed to set DUID: %m"); break; } case DHCP_CLIENT_ID_MAC: { const uint8_t *hw_addr = link->hw_addr.addr.bytes; size_t hw_addr_len = link->hw_addr.length; if (link->iftype == ARPHRD_INFINIBAND && hw_addr_len == INFINIBAND_ALEN) { /* set_client_id expects only last 8 bytes of an IB address */ hw_addr += INFINIBAND_ALEN - 8; hw_addr_len -= INFINIBAND_ALEN - 8; } r = sd_dhcp_client_set_client_id(link->dhcp_client, link->iftype, hw_addr, hw_addr_len); if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to set client ID: %m"); break; } default: assert_not_reached("Unknown client identifier type."); } return 0; } static int dhcp4_set_request_address(Link *link) { Address *a; assert(link); assert(link->network); assert(link->dhcp_client); if (!FLAGS_SET(link->network->keep_configuration, KEEP_CONFIGURATION_DHCP)) return 0; SET_FOREACH(a, link->addresses_foreign) { if (a->family != AF_INET) continue; if (link_address_is_dynamic(link, a)) break; } if (!a) return 0; log_link_debug(link, "DHCP4 CLIENT: requesting " IPV4_ADDRESS_FMT_STR, IPV4_ADDRESS_FMT_VAL(a->in_addr.in)); return sd_dhcp_client_set_request_address(link->dhcp_client, &a->in_addr.in); } int dhcp4_configure(Link *link) { sd_dhcp_option *send_option; void *request_options; int r; assert(link); assert(link->network); if (!link_dhcp4_enabled(link)) return 0; if (!link->dhcp_client) { r = sd_dhcp_client_new(&link->dhcp_client, link->network->dhcp_anonymize); if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to allocate DHCP4 client: %m"); r = sd_dhcp_client_attach_event(link->dhcp_client, link->manager->event, 0); if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to attach event to DHCP4 client: %m"); } r = sd_dhcp_client_set_mac(link->dhcp_client, link->hw_addr.addr.bytes, link->bcast_addr.length > 0 ? link->bcast_addr.addr.bytes : NULL, link->hw_addr.length, link->iftype); if (r < 0) return log_link_warning_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_warning_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_warning_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_warning_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for broadcast: %m"); if (link->mtu > 0) { r = sd_dhcp_client_set_mtu(link->dhcp_client, link->mtu); if (r < 0) return log_link_warning_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_warning_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_warning_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_warning_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_warning_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_warning_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for NTP server: %m"); } if (link->network->dhcp_use_sip) { r = sd_dhcp_client_set_request_option(link->dhcp_client, SD_DHCP_OPTION_SIP_SERVER); if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for SIP 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_warning_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for timezone: %m"); } SET_FOREACH(request_options, link->network->dhcp_request_options) { uint32_t option = PTR_TO_UINT32(request_options); r = sd_dhcp_client_set_request_option(link->dhcp_client, option); if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to set request flag for '%u': %m", option); } ORDERED_HASHMAP_FOREACH(send_option, link->network->dhcp_client_send_options) { r = sd_dhcp_client_add_option(link->dhcp_client, send_option); if (r == -EEXIST) continue; if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to set send option: %m"); } ORDERED_HASHMAP_FOREACH(send_option, link->network->dhcp_client_send_vendor_options) { r = sd_dhcp_client_add_vendor_option(link->dhcp_client, send_option); if (r == -EEXIST) continue; if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to set send option: %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_warning_errno(link, r, "DHCP4 CLIENT: Failed to set vendor class identifier: %m"); } if (link->network->dhcp_mudurl) { r = sd_dhcp_client_set_mud_url(link->dhcp_client, link->network->dhcp_mudurl); if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to set MUD URL: %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_warning_errno(link, r, "DHCP4 CLIENT: Failed to set user class: %m"); } if (link->network->dhcp_client_port > 0) { r = sd_dhcp_client_set_client_port(link->dhcp_client, link->network->dhcp_client_port); if (r < 0) return log_link_warning_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_warning_errno(link, r, "DHCP4 CLIENT: Failed to set max attempts: %m"); } if (link->network->dhcp_ip_service_type > 0) { r = sd_dhcp_client_set_service_type(link->dhcp_client, link->network->dhcp_ip_service_type); if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to set IP service type: %m"); } if (link->network->dhcp_fallback_lease_lifetime > 0) { r = sd_dhcp_client_set_fallback_lease_lifetime(link->dhcp_client, link->network->dhcp_fallback_lease_lifetime); if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed set to lease lifetime: %m"); } r = dhcp4_set_request_address(link); if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to set initial DHCPv4 address: %m"); r = dhcp4_configure_dad(link); if (r < 0) return log_link_warning_errno(link, r, "DHCP4 CLIENT: Failed to configure service type: %m"); return dhcp4_set_client_identifier(link); } int dhcp4_update_mac(Link *link) { int r; assert(link); if (!link->dhcp_client) return 0; r = sd_dhcp_client_set_mac(link->dhcp_client, link->hw_addr.addr.bytes, link->bcast_addr.length > 0 ? link->bcast_addr.addr.bytes : NULL, link->hw_addr.length, link->iftype); if (r < 0) return r; r = dhcp4_set_client_identifier(link); if (r < 0) return r; r = dhcp4_dad_update_mac(link); if (r < 0) return r; return 0; } 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_WARNING, filename, line, r, "Failed to parse DHCP maximum attempts, ignoring: %s", rvalue); return 0; } if (a == 0) { log_syntax(unit, LOG_WARNING, 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_acl_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; Set **acl; int r; assert(filename); assert(lvalue); assert(rvalue); assert(data); acl = STR_IN_SET(lvalue, "DenyList", "BlackList") ? &network->dhcp_deny_listed_ip : &network->dhcp_allow_listed_ip; if (isempty(rvalue)) { *acl = set_free(*acl); return 0; } for (const char *p = rvalue;;) { _cleanup_free_ char *n = NULL; union in_addr_union ip; r = extract_first_word(&p, &n, NULL, 0); if (r == -ENOMEM) return log_oom(); if (r < 0) { log_syntax(unit, LOG_WARNING, filename, line, r, "Failed to parse DHCP '%s=' IP address, ignoring assignment: %s", lvalue, rvalue); return 0; } if (r == 0) return 0; r = in_addr_from_string(AF_INET, n, &ip); if (r < 0) { log_syntax(unit, LOG_WARNING, filename, line, r, "DHCP '%s=' IP address is invalid, ignoring assignment: %s", lvalue, n); continue; } r = set_ensure_put(acl, NULL, UINT32_TO_PTR(ip.in.s_addr)); if (r < 0) log_syntax(unit, LOG_WARNING, filename, line, r, "Failed to store DHCP '%s=' IP address '%s', ignoring assignment: %m", lvalue, n); } } int config_parse_dhcp_ip_service_type( 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) { assert(filename); assert(lvalue); assert(rvalue); if (streq(rvalue, "CS4")) *((int *)data) = IPTOS_CLASS_CS4; else if (streq(rvalue, "CS6")) *((int *)data) = IPTOS_CLASS_CS6; else log_syntax(unit, LOG_WARNING, filename, line, 0, "Failed to parse IPServiceType type '%s', ignoring.", rvalue); return 0; } int config_parse_dhcp_mud_url( 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) { _cleanup_free_ char *unescaped = NULL; Network *network = data; int r; assert(filename); assert(lvalue); assert(rvalue); if (isempty(rvalue)) { network->dhcp_mudurl = mfree(network->dhcp_mudurl); return 0; } r = cunescape(rvalue, 0, &unescaped); if (r < 0) { log_syntax(unit, LOG_WARNING, filename, line, r, "Failed to Failed to unescape MUD URL, ignoring: %s", rvalue); return 0; } if (!http_url_is_valid(unescaped) || strlen(unescaped) > 255) { log_syntax(unit, LOG_WARNING, filename, line, 0, "Failed to parse MUD URL '%s', ignoring: %m", rvalue); return 0; } return free_and_strdup_warn(&network->dhcp_mudurl, unescaped); } int config_parse_dhcp_fallback_lease_lifetime(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 = userdata; uint32_t k; assert(filename); assert(section); assert(lvalue); assert(rvalue); assert(data); if (isempty(rvalue)) { network->dhcp_fallback_lease_lifetime = 0; return 0; } /* We accept only "forever" or "infinity". */ if (STR_IN_SET(rvalue, "forever", "infinity")) k = CACHE_INFO_INFINITY_LIFE_TIME; else { log_syntax(unit, LOG_WARNING, filename, line, 0, "Invalid LeaseLifetime= value, ignoring: %s", rvalue); return 0; } network->dhcp_fallback_lease_lifetime = k; 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");