/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include "sd-dhcp-client.h" #include "sd-ipv4acd.h" #include "networkd-address.h" #include "networkd-dhcp4.h" #include "networkd-ipv4acd.h" #include "networkd-link.h" #include "networkd-manager.h" static int static_ipv4acd_address_remove(Link *link, Address *address, bool on_conflict) { int r; assert(link); assert(address); /* Prevent form the address being freed. */ address_enter_probing(address); if (!address_exists(address)) return 0; /* Not assigned. */ if (on_conflict) log_link_warning(link, "Dropping address "IPV4_ADDRESS_FMT_STR", as an address conflict was detected.", IPV4_ADDRESS_FMT_VAL(address->in_addr.in)); else log_link_debug(link, "Removing address "IPV4_ADDRESS_FMT_STR", as the ACD client is stopped.", IPV4_ADDRESS_FMT_VAL(address->in_addr.in)); r = address_remove(address); if (r < 0) return log_link_warning_errno(link, r, "Failed to remove address "IPV4_ADDRESS_FMT_STR": %m", IPV4_ADDRESS_FMT_VAL(address->in_addr.in)); return 0; } static int dhcp4_address_on_conflict(Link *link, Address *address) { int r; assert(link); assert(link->dhcp_client); 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) /* Unlikely, but during probing the address, the lease may be lost. */ return 0; log_link_warning(link, "Dropping DHCPv4 lease, as an address conflict was detected."); r = dhcp4_lease_lost(link); if (r < 0) return log_link_warning_errno(link, r, "Failed to drop DHCPv4 lease: %m"); /* make the address will be freed. */ address_cancel_probing(address); /* It is not necessary to call address_remove() here, as dhcp4_lease_lost() removes it. */ return 0; } static void on_acd(sd_ipv4acd *acd, int event, void *userdata) { Address *address = userdata; Link *link; int r; assert(acd); assert(address); assert(address->acd == acd); assert(address->link); assert(address->family == AF_INET); assert(IN_SET(address->source, NETWORK_CONFIG_SOURCE_STATIC, NETWORK_CONFIG_SOURCE_DHCP4)); link = address->link; switch (event) { case SD_IPV4ACD_EVENT_STOP: if (address->source == NETWORK_CONFIG_SOURCE_STATIC) { r = static_ipv4acd_address_remove(link, address, /* on_conflict = */ false); if (r < 0) link_enter_failed(link); } /* We have nothing to do for DHCPv4 lease here, as the dhcp client is already stopped * when stopping the ipv4acd client. See link_stop_engines(). */ break; case SD_IPV4ACD_EVENT_BIND: log_link_debug(link, "Successfully claimed address "IPV4_ADDRESS_FMT_STR, IPV4_ADDRESS_FMT_VAL(address->in_addr.in)); address_cancel_probing(address); break; case SD_IPV4ACD_EVENT_CONFLICT: log_link_warning(link, "Dropping address "IPV4_ADDRESS_FMT_STR", as an address conflict was detected.", IPV4_ADDRESS_FMT_VAL(address->in_addr.in)); if (address->source == NETWORK_CONFIG_SOURCE_STATIC) r = static_ipv4acd_address_remove(link, address, /* on_conflict = */ true); else r = dhcp4_address_on_conflict(link, address); if (r < 0) link_enter_failed(link); break; default: assert_not_reached(); } } static int ipv4acd_check_mac(sd_ipv4acd *acd, const struct ether_addr *mac, void *userdata) { Manager *m = userdata; struct hw_addr_data hw_addr; assert(m); assert(mac); hw_addr = (struct hw_addr_data) { .length = ETH_ALEN, .ether = *mac, }; return link_get_by_hw_addr(m, &hw_addr, NULL) >= 0; } int ipv4acd_configure(Address *address) { Link *link; int r; assert(address); assert(address->link); if (address->family != AF_INET) return 0; if (!FLAGS_SET(address->duplicate_address_detection, ADDRESS_FAMILY_IPV4)) return 0; /* Currently, only static and DHCP4 addresses are supported. */ assert(IN_SET(address->source, NETWORK_CONFIG_SOURCE_STATIC, NETWORK_CONFIG_SOURCE_DHCP4)); if (address->acd) { address_enter_probing(address); return 0; } link = address->link; log_link_debug(link, "Configuring IPv4ACD for address "IPV4_ADDRESS_FMT_STR, IPV4_ADDRESS_FMT_VAL(address->in_addr.in)); r = sd_ipv4acd_new(&address->acd); if (r < 0) return r; r = sd_ipv4acd_attach_event(address->acd, link->manager->event, 0); if (r < 0) return r; r = sd_ipv4acd_set_ifindex(address->acd, link->ifindex); if (r < 0) return r; r = sd_ipv4acd_set_mac(address->acd, &link->hw_addr.ether); if (r < 0) return r; r = sd_ipv4acd_set_address(address->acd, &address->in_addr.in); if (r < 0) return r; r = sd_ipv4acd_set_callback(address->acd, on_acd, address); if (r < 0) return r; r = sd_ipv4acd_set_check_mac_callback(address->acd, ipv4acd_check_mac, link->manager); if (r < 0) return r; if (link_has_carrier(link)) { r = sd_ipv4acd_start(address->acd, true); if (r < 0) return r; } address_enter_probing(address); return 0; } int ipv4acd_update_mac(Link *link) { Address *address; int k, r = 0; assert(link); if (link->hw_addr.length != ETH_ALEN) return 0; if (ether_addr_is_null(&link->hw_addr.ether)) return 0; SET_FOREACH(address, link->addresses) { if (!address->acd) continue; k = sd_ipv4acd_set_mac(address->acd, &link->hw_addr.ether); if (k < 0) r = k; } if (r < 0) link_enter_failed(link); return r; } int ipv4acd_start(Link *link) { Address *address; int r; assert(link); SET_FOREACH(address, link->addresses) { if (!address->acd) continue; if (sd_ipv4acd_is_running(address->acd)) continue; r = sd_ipv4acd_start(address->acd, true); if (r < 0) return r; } return 0; } int ipv4acd_stop(Link *link) { Address *address; int k, r = 0; assert(link); SET_FOREACH(address, link->addresses) { if (!address->acd) continue; k = sd_ipv4acd_stop(address->acd); if (k < 0) r = k; } return r; } int ipv4acd_set_ifname(Link *link) { Address *address; int r; assert(link); SET_FOREACH(address, link->addresses) { if (!address->acd) continue; r = sd_ipv4acd_set_ifname(address->acd, link->ifname); if (r < 0) return r; } return 0; }