/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include #include #include "in-addr-util.h" #include "networkd-address.h" #include "networkd-ipv6ll.h" #include "networkd-link.h" #include "networkd-network.h" #include "networkd-util.h" #include "socket-util.h" #include "string-table.h" #include "strv.h" #include "sysctl-util.h" bool link_ipv6ll_enabled(Link *link) { assert(link); if (!socket_ipv6_is_supported()) return false; if (link->flags & IFF_LOOPBACK) return false; if (!link->network) return false; if (link->iftype == ARPHRD_CAN) return false; if (STRPTR_IN_SET(link->kind, "vrf", "wireguard", "ipip", "gre", "sit", "vti", "nlmon")) return false; if (link->network->bond) return false; return link->network->link_local & ADDRESS_FAMILY_IPV6; } bool link_may_have_ipv6ll(Link *link, bool check_multicast) { assert(link); /* * This is equivalent to link_ipv6ll_enabled() for non-WireGuard interfaces. * * For WireGuard interface, the kernel does not assign any IPv6LL addresses, but we can assign * it manually. It is necessary to set an IPv6LL address manually to run NDisc or RADV on * WireGuard interface. Note, also Multicast=yes must be set. See #17380. * * TODO: May be better to introduce GenerateIPv6LinkLocalAddress= setting, and use algorithms * used in networkd-address-generation.c */ if (link_ipv6ll_enabled(link)) return true; /* IPv6LL address can be manually assigned on WireGuard interface. */ if (streq_ptr(link->kind, "wireguard")) { Address *a; if (!link->network) return false; if (check_multicast && !FLAGS_SET(link->flags, IFF_MULTICAST) && link->network->multicast <= 0) return false; ORDERED_HASHMAP_FOREACH(a, link->network->addresses_by_section) { if (a->family != AF_INET6) continue; if (in6_addr_is_set(&a->in_addr_peer.in6)) continue; if (in6_addr_is_link_local(&a->in_addr.in6)) return true; } } return false; } IPv6LinkLocalAddressGenMode link_get_ipv6ll_addrgen_mode(Link *link) { assert(link); if (!link_ipv6ll_enabled(link)) return IPV6_LINK_LOCAL_ADDRESSS_GEN_MODE_NONE; if (link->network->ipv6ll_address_gen_mode >= 0) return link->network->ipv6ll_address_gen_mode; if (in6_addr_is_set(&link->network->ipv6ll_stable_secret)) return IPV6_LINK_LOCAL_ADDRESSS_GEN_MODE_STABLE_PRIVACY; return IPV6_LINK_LOCAL_ADDRESSS_GEN_MODE_EUI64; } int ipv6ll_addrgen_mode_fill_message(sd_netlink_message *message, IPv6LinkLocalAddressGenMode mode) { int r; assert(message); assert(mode >= 0 && mode < _IPV6_LINK_LOCAL_ADDRESS_GEN_MODE_MAX); r = sd_netlink_message_open_container(message, IFLA_AF_SPEC); if (r < 0) return r; r = sd_netlink_message_open_container(message, AF_INET6); if (r < 0) return r; r = sd_netlink_message_append_u8(message, IFLA_INET6_ADDR_GEN_MODE, mode); if (r < 0) return r; r = sd_netlink_message_close_container(message); if (r < 0) return r; r = sd_netlink_message_close_container(message); if (r < 0) return r; return 0; } int link_update_ipv6ll_addrgen_mode(Link *link, sd_netlink_message *message) { uint8_t mode; int family, r; assert(link); assert(message); r = sd_rtnl_message_get_family(message, &family); if (r < 0) return r; if (family != AF_UNSPEC) return 0; r = sd_netlink_message_enter_container(message, IFLA_AF_SPEC); if (r == -ENODATA) return 0; if (r < 0) return r; r = sd_netlink_message_enter_container(message, AF_INET6); if (r == -ENODATA) return sd_netlink_message_exit_container(message); if (r < 0) return r; mode = (uint8_t) link->ipv6ll_address_gen_mode; r = sd_netlink_message_read_u8(message, IFLA_INET6_ADDR_GEN_MODE, &mode); if (r < 0 && r != -ENODATA) return r; r = sd_netlink_message_exit_container(message); if (r < 0) return r; r = sd_netlink_message_exit_container(message); if (r < 0) return r; if (mode == (uint8_t) link->ipv6ll_address_gen_mode) return 0; if (mode >= _IPV6_LINK_LOCAL_ADDRESS_GEN_MODE_MAX) { log_link_debug(link, "Received invalid IPv6 link-local address generation mode (%u), ignoring.", mode); return 0; } if (link->ipv6ll_address_gen_mode < 0) log_link_debug(link, "Saved IPv6 link-local address generation mode: %s", ipv6_link_local_address_gen_mode_to_string(mode)); else log_link_debug(link, "IPv6 link-local address generation mode is changed: %s -> %s", ipv6_link_local_address_gen_mode_to_string(link->ipv6ll_address_gen_mode), ipv6_link_local_address_gen_mode_to_string(mode)); link->ipv6ll_address_gen_mode = mode; return 0; } #define STABLE_SECRET_APP_ID_1 SD_ID128_MAKE(aa,05,1d,94,43,68,45,07,b9,73,f1,e8,e4,b7,34,52) #define STABLE_SECRET_APP_ID_2 SD_ID128_MAKE(52,c4,40,a0,9f,2f,48,58,a9,3a,f6,29,25,ba,7a,7d) int link_set_ipv6ll_stable_secret(Link *link) { struct in6_addr a; int r; assert(link); assert(link->network); if (link->network->ipv6ll_address_gen_mode != IPV6_LINK_LOCAL_ADDRESSS_GEN_MODE_STABLE_PRIVACY) return 0; if (in6_addr_is_set(&link->network->ipv6ll_stable_secret)) a = link->network->ipv6ll_stable_secret; else { sd_id128_t key; le64_t v; /* Generate a stable secret address from machine-ID and the interface name. */ r = sd_id128_get_machine_app_specific(STABLE_SECRET_APP_ID_1, &key); if (r < 0) return log_link_debug_errno(link, r, "Failed to generate key: %m"); v = htole64(siphash24_string(link->ifname, key.bytes)); memcpy(a.s6_addr, &v, sizeof(v)); r = sd_id128_get_machine_app_specific(STABLE_SECRET_APP_ID_2, &key); if (r < 0) return log_link_debug_errno(link, r, "Failed to generate key: %m"); v = htole64(siphash24_string(link->ifname, key.bytes)); assert_cc(sizeof(v) * 2 == sizeof(a.s6_addr)); memcpy(a.s6_addr + sizeof(v), &v, sizeof(v)); } return sysctl_write_ip_property(AF_INET6, link->ifname, "stable_secret", IN6_ADDR_TO_STRING(&a)); } int link_set_ipv6ll_addrgen_mode(Link *link, IPv6LinkLocalAddressGenMode mode) { assert(link); assert(mode >= 0 && mode < _IPV6_LINK_LOCAL_ADDRESS_GEN_MODE_MAX); if (mode == link->ipv6ll_address_gen_mode) return 0; return sysctl_write_ip_property_uint32(AF_INET6, link->ifname, "addr_gen_mode", mode); } static const char* const ipv6_link_local_address_gen_mode_table[_IPV6_LINK_LOCAL_ADDRESS_GEN_MODE_MAX] = { [IPV6_LINK_LOCAL_ADDRESSS_GEN_MODE_EUI64] = "eui64", [IPV6_LINK_LOCAL_ADDRESSS_GEN_MODE_NONE] = "none", [IPV6_LINK_LOCAL_ADDRESSS_GEN_MODE_STABLE_PRIVACY] = "stable-privacy", [IPV6_LINK_LOCAL_ADDRESSS_GEN_MODE_RANDOM] = "random", }; DEFINE_STRING_TABLE_LOOKUP(ipv6_link_local_address_gen_mode, IPv6LinkLocalAddressGenMode); DEFINE_CONFIG_PARSE_ENUM( config_parse_ipv6_link_local_address_gen_mode, ipv6_link_local_address_gen_mode, IPv6LinkLocalAddressGenMode, "Failed to parse IPv6 link-local address generation mode");