From b750101eb236130cf056c675997decbac904cc49 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:35:18 +0200 Subject: Adding upstream version 252.22. Signed-off-by: Daniel Baumann --- src/network/networkd-ndisc.c | 1211 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1211 insertions(+) create mode 100644 src/network/networkd-ndisc.c (limited to 'src/network/networkd-ndisc.c') diff --git a/src/network/networkd-ndisc.c b/src/network/networkd-ndisc.c new file mode 100644 index 0000000..5fb5d96 --- /dev/null +++ b/src/network/networkd-ndisc.c @@ -0,0 +1,1211 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/*** + Copyright © 2014 Intel Corporation. All rights reserved. +***/ + +#include +#include +#include +#include + +#include "sd-ndisc.h" + +#include "event-util.h" +#include "missing_network.h" +#include "networkd-address-generation.h" +#include "networkd-address.h" +#include "networkd-dhcp6.h" +#include "networkd-manager.h" +#include "networkd-ndisc.h" +#include "networkd-queue.h" +#include "networkd-route.h" +#include "networkd-state-file.h" +#include "string-table.h" +#include "string-util.h" +#include "strv.h" + +#define NDISC_DNSSL_MAX 64U +#define NDISC_RDNSS_MAX 64U + +bool link_ipv6_accept_ra_enabled(Link *link) { + assert(link); + + if (!socket_ipv6_is_supported()) + return false; + + if (link->flags & IFF_LOOPBACK) + return false; + + if (link->iftype == ARPHRD_CAN) + return false; + + if (!link->network) + return false; + + if (!link_may_have_ipv6ll(link, /* check_multicast = */ true)) + return false; + + assert(link->network->ipv6_accept_ra >= 0); + return link->network->ipv6_accept_ra; +} + +void network_adjust_ipv6_accept_ra(Network *network) { + assert(network); + + if (!FLAGS_SET(network->link_local, ADDRESS_FAMILY_IPV6)) { + if (network->ipv6_accept_ra > 0) + log_warning("%s: IPv6AcceptRA= is enabled but IPv6 link-local addressing is disabled or not supported. " + "Disabling IPv6AcceptRA=.", network->filename); + network->ipv6_accept_ra = false; + } + + if (network->ipv6_accept_ra < 0) + /* default to accept RA if ip_forward is disabled and ignore RA if ip_forward is enabled */ + network->ipv6_accept_ra = !FLAGS_SET(network->ip_forward, ADDRESS_FAMILY_IPV6); + + /* When RouterAllowList=, PrefixAllowList= or RouteAllowList= are specified, then + * RouterDenyList=, PrefixDenyList= or RouteDenyList= are ignored, respectively. */ + if (!set_isempty(network->ndisc_allow_listed_router)) + network->ndisc_deny_listed_router = set_free_free(network->ndisc_deny_listed_router); + if (!set_isempty(network->ndisc_allow_listed_prefix)) + network->ndisc_deny_listed_prefix = set_free_free(network->ndisc_deny_listed_prefix); + if (!set_isempty(network->ndisc_allow_listed_route_prefix)) + network->ndisc_deny_listed_route_prefix = set_free_free(network->ndisc_deny_listed_route_prefix); +} + +static int ndisc_check_ready(Link *link); + +static int ndisc_address_ready_callback(Address *address) { + Address *a; + + assert(address); + assert(address->link); + + SET_FOREACH(a, address->link->addresses) + if (a->source == NETWORK_CONFIG_SOURCE_NDISC) + a->callback = NULL; + + return ndisc_check_ready(address->link); +} + +static int ndisc_check_ready(Link *link) { + bool found = false, ready = false; + Address *address; + + assert(link); + + if (link->ndisc_messages > 0) { + log_link_debug(link, "%s(): SLAAC addresses and routes are not set.", __func__); + return 0; + } + + SET_FOREACH(address, link->addresses) { + if (address->source != NETWORK_CONFIG_SOURCE_NDISC) + continue; + + found = true; + + if (address_is_ready(address)) { + ready = true; + break; + } + } + + if (found && !ready) { + SET_FOREACH(address, link->addresses) + if (address->source == NETWORK_CONFIG_SOURCE_NDISC) + address->callback = ndisc_address_ready_callback; + + log_link_debug(link, "%s(): no SLAAC address is ready.", __func__); + return 0; + } + + link->ndisc_configured = true; + log_link_debug(link, "SLAAC addresses and routes set."); + + link_check_ready(link); + return 0; +} + +static int ndisc_route_handler(sd_netlink *rtnl, sd_netlink_message *m, Request *req, Link *link, Route *route) { + int r; + + assert(link); + + r = route_configure_handler_internal(rtnl, m, link, "Could not set NDisc route"); + if (r <= 0) + return r; + + r = ndisc_check_ready(link); + if (r < 0) + link_enter_failed(link); + + return 1; +} + +static int ndisc_request_route(Route *in, Link *link, sd_ndisc_router *rt) { + _cleanup_(route_freep) Route *route = in; + struct in6_addr router; + bool is_new; + int r; + + assert(route); + assert(link); + assert(rt); + + r = sd_ndisc_router_get_address(rt, &router); + if (r < 0) + return r; + + route->source = NETWORK_CONFIG_SOURCE_NDISC; + route->provider.in6 = router; + if (!route->table_set) + route->table = link_get_ipv6_accept_ra_route_table(link); + if (!route->priority_set) + route->priority = link->network->ipv6_accept_ra_route_metric; + if (!route->protocol_set) + route->protocol = RTPROT_RA; + + is_new = route_get(NULL, link, route, NULL) < 0; + + r = link_request_route(link, TAKE_PTR(route), true, &link->ndisc_messages, + ndisc_route_handler, NULL); + if (r < 0) + return r; + if (r > 0 && is_new) + link->ndisc_configured = false; + + return 0; +} + +static int ndisc_address_handler(sd_netlink *rtnl, sd_netlink_message *m, Request *req, Link *link, Address *address) { + int r; + + assert(link); + + r = address_configure_handler_internal(rtnl, m, link, "Could not set NDisc address"); + if (r <= 0) + return r; + + r = ndisc_check_ready(link); + if (r < 0) + link_enter_failed(link); + + return 1; +} + +static int ndisc_request_address(Address *in, Link *link, sd_ndisc_router *rt) { + _cleanup_(address_freep) Address *address = in; + struct in6_addr router; + bool is_new; + int r; + + assert(address); + assert(link); + assert(rt); + + r = sd_ndisc_router_get_address(rt, &router); + if (r < 0) + return r; + + address->source = NETWORK_CONFIG_SOURCE_NDISC; + address->provider.in6 = router; + + r = free_and_strdup_warn(&address->netlabel, link->network->ndisc_netlabel); + if (r < 0) + return r; + + is_new = address_get(link, address, NULL) < 0; + + r = link_request_address(link, TAKE_PTR(address), true, &link->ndisc_messages, + ndisc_address_handler, NULL); + if (r < 0) + return r; + if (r > 0 && is_new) + link->ndisc_configured = false; + + return 0; +} + +static int ndisc_router_process_default(Link *link, sd_ndisc_router *rt) { + usec_t lifetime_usec, timestamp_usec; + struct in6_addr gateway; + uint16_t lifetime_sec; + unsigned preference; + uint32_t mtu = 0; + int r; + + assert(link); + assert(link->network); + assert(rt); + + if (!link->network->ipv6_accept_ra_use_gateway && + hashmap_isempty(link->network->routes_by_section)) + return 0; + + r = sd_ndisc_router_get_lifetime(rt, &lifetime_sec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get gateway lifetime from RA: %m"); + + r = sd_ndisc_router_get_timestamp(rt, CLOCK_BOOTTIME, ×tamp_usec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); + + lifetime_usec = sec16_to_usec(lifetime_sec, timestamp_usec); + + r = sd_ndisc_router_get_address(rt, &gateway); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get gateway address from RA: %m"); + + if (link_get_ipv6_address(link, &gateway, 0, NULL) >= 0) { + if (DEBUG_LOGGING) + log_link_debug(link, "No NDisc route added, gateway %s matches local address", + IN6_ADDR_TO_STRING(&gateway)); + return 0; + } + + r = sd_ndisc_router_get_preference(rt, &preference); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get default router preference from RA: %m"); + + if (link->network->ipv6_accept_ra_use_mtu) { + r = sd_ndisc_router_get_mtu(rt, &mtu); + if (r < 0 && r != -ENODATA) + return log_link_error_errno(link, r, "Failed to get default router MTU from RA: %m"); + } + + if (link->network->ipv6_accept_ra_use_gateway) { + _cleanup_(route_freep) Route *route = NULL; + + r = route_new(&route); + if (r < 0) + return log_oom(); + + route->family = AF_INET6; + route->pref = preference; + route->gw_family = AF_INET6; + route->gw.in6 = gateway; + route->lifetime_usec = lifetime_usec; + route->mtu = mtu; + + r = ndisc_request_route(TAKE_PTR(route), link, rt); + if (r < 0) + return log_link_error_errno(link, r, "Could not request default route: %m"); + } + + Route *route_gw; + HASHMAP_FOREACH(route_gw, link->network->routes_by_section) { + _cleanup_(route_freep) Route *route = NULL; + + if (!route_gw->gateway_from_dhcp_or_ra) + continue; + + if (route_gw->gw_family != AF_INET6) + continue; + + r = route_dup(route_gw, &route); + if (r < 0) + return r; + + route->gw.in6 = gateway; + if (!route->pref_set) + route->pref = preference; + route->lifetime_usec = lifetime_usec; + if (route->mtu == 0) + route->mtu = mtu; + + r = ndisc_request_route(TAKE_PTR(route), link, rt); + if (r < 0) + return log_link_error_errno(link, r, "Could not request gateway: %m"); + } + + return 0; +} + +static int ndisc_router_process_autonomous_prefix(Link *link, sd_ndisc_router *rt) { + uint32_t lifetime_valid_sec, lifetime_preferred_sec; + usec_t lifetime_valid_usec, lifetime_preferred_usec, timestamp_usec; + _cleanup_set_free_ Set *addresses = NULL; + struct in6_addr prefix, *a; + unsigned prefixlen; + int r; + + assert(link); + assert(link->network); + assert(rt); + + if (!link->network->ipv6_accept_ra_use_autonomous_prefix) + return 0; + + r = sd_ndisc_router_get_timestamp(rt, CLOCK_BOOTTIME, ×tamp_usec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); + + r = sd_ndisc_router_prefix_get_address(rt, &prefix); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get prefix address: %m"); + + r = sd_ndisc_router_prefix_get_prefixlen(rt, &prefixlen); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get prefix length: %m"); + + /* ndisc_generate_addresses() below requires the prefix length <= 64. */ + if (prefixlen > 64) { + log_link_debug(link, "Prefix is longer than 64, ignoring autonomous prefix %s.", + IN6_ADDR_PREFIX_TO_STRING(&prefix, prefixlen)); + return 0; + } + + r = sd_ndisc_router_prefix_get_valid_lifetime(rt, &lifetime_valid_sec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get prefix valid lifetime: %m"); + + r = sd_ndisc_router_prefix_get_preferred_lifetime(rt, &lifetime_preferred_sec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get prefix preferred lifetime: %m"); + + /* The preferred lifetime is never greater than the valid lifetime */ + if (lifetime_preferred_sec > lifetime_valid_sec) + return 0; + + lifetime_valid_usec = sec_to_usec(lifetime_valid_sec, timestamp_usec); + lifetime_preferred_usec = sec_to_usec(lifetime_preferred_sec, timestamp_usec); + + r = ndisc_generate_addresses(link, &prefix, prefixlen, &addresses); + if (r < 0) + return log_link_error_errno(link, r, "Failed to generate SLAAC addresses: %m"); + + SET_FOREACH(a, addresses) { + _cleanup_(address_freep) Address *address = NULL; + + r = address_new(&address); + if (r < 0) + return log_oom(); + + address->family = AF_INET6; + address->in_addr.in6 = *a; + address->prefixlen = prefixlen; + address->flags = IFA_F_NOPREFIXROUTE|IFA_F_MANAGETEMPADDR; + address->lifetime_valid_usec = lifetime_valid_usec; + address->lifetime_preferred_usec = lifetime_preferred_usec; + + r = ndisc_request_address(TAKE_PTR(address), link, rt); + if (r < 0) + return log_link_error_errno(link, r, "Could not request SLAAC address: %m"); + } + + return 0; +} + +static int ndisc_router_process_onlink_prefix(Link *link, sd_ndisc_router *rt) { + _cleanup_(route_freep) Route *route = NULL; + usec_t timestamp_usec; + uint32_t lifetime_sec; + struct in6_addr prefix; + unsigned prefixlen; + int r; + + assert(link); + assert(link->network); + assert(rt); + + if (!link->network->ipv6_accept_ra_use_onlink_prefix) + return 0; + + r = sd_ndisc_router_prefix_get_valid_lifetime(rt, &lifetime_sec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get prefix lifetime: %m"); + + r = sd_ndisc_router_get_timestamp(rt, CLOCK_BOOTTIME, ×tamp_usec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); + + r = sd_ndisc_router_prefix_get_address(rt, &prefix); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get prefix address: %m"); + + r = sd_ndisc_router_prefix_get_prefixlen(rt, &prefixlen); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get prefix length: %m"); + + r = route_new(&route); + if (r < 0) + return log_oom(); + + route->family = AF_INET6; + route->flags = RTM_F_PREFIX; + route->dst.in6 = prefix; + route->dst_prefixlen = prefixlen; + route->lifetime_usec = sec_to_usec(lifetime_sec, timestamp_usec); + + r = ndisc_request_route(TAKE_PTR(route), link, rt); + if (r < 0) + return log_link_error_errno(link, r, "Could not request prefix route: %m"); + + return 0; +} + +static int ndisc_router_process_prefix(Link *link, sd_ndisc_router *rt) { + unsigned prefixlen; + struct in6_addr a; + uint8_t flags; + int r; + + assert(link); + assert(link->network); + assert(rt); + + r = sd_ndisc_router_prefix_get_address(rt, &a); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get prefix address: %m"); + + /* RFC 4861 Section 4.6.2: + * A router SHOULD NOT send a prefix option for the link-local prefix and a host SHOULD ignore such + * a prefix option. */ + if (in6_addr_is_link_local(&a)) { + log_link_debug(link, "Received link-local prefix, ignoring autonomous prefix."); + return 0; + } + + r = sd_ndisc_router_prefix_get_prefixlen(rt, &prefixlen); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get prefix length: %m"); + + if (in6_prefix_is_filtered(&a, prefixlen, link->network->ndisc_allow_listed_prefix, link->network->ndisc_deny_listed_prefix)) { + if (DEBUG_LOGGING) + log_link_debug(link, "Prefix '%s' is %s, ignoring", + !set_isempty(link->network->ndisc_allow_listed_prefix) ? "not in allow list" + : "in deny list", + IN6_ADDR_PREFIX_TO_STRING(&a, prefixlen)); + return 0; + } + + r = sd_ndisc_router_prefix_get_flags(rt, &flags); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get RA prefix flags: %m"); + + if (FLAGS_SET(flags, ND_OPT_PI_FLAG_ONLINK)) { + r = ndisc_router_process_onlink_prefix(link, rt); + if (r < 0) + return r; + } + + if (FLAGS_SET(flags, ND_OPT_PI_FLAG_AUTO)) { + r = ndisc_router_process_autonomous_prefix(link, rt); + if (r < 0) + return r; + } + + return 0; +} + +static int ndisc_router_process_route(Link *link, sd_ndisc_router *rt) { + _cleanup_(route_freep) Route *route = NULL; + unsigned preference, prefixlen; + struct in6_addr gateway, dst; + uint32_t lifetime_sec; + usec_t timestamp_usec; + int r; + + assert(link); + + if (!link->network->ipv6_accept_ra_use_route_prefix) + return 0; + + r = sd_ndisc_router_route_get_lifetime(rt, &lifetime_sec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get route lifetime from RA: %m"); + + r = sd_ndisc_router_route_get_address(rt, &dst); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get route destination address: %m"); + + r = sd_ndisc_router_route_get_prefixlen(rt, &prefixlen); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get route prefix length: %m"); + + if (in6_addr_is_null(&dst) && prefixlen == 0) { + log_link_debug(link, "Route prefix is ::/0, ignoring"); + return 0; + } + + if (in6_prefix_is_filtered(&dst, prefixlen, + link->network->ndisc_allow_listed_route_prefix, + link->network->ndisc_deny_listed_route_prefix)) { + + if (DEBUG_LOGGING) + log_link_debug(link, "Route prefix %s is %s, ignoring", + !set_isempty(link->network->ndisc_allow_listed_route_prefix) ? "not in allow list" + : "in deny list", + IN6_ADDR_PREFIX_TO_STRING(&dst, prefixlen)); + return 0; + } + + r = sd_ndisc_router_get_address(rt, &gateway); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get gateway address from RA: %m"); + + if (link_get_ipv6_address(link, &gateway, 0, NULL) >= 0) { + if (DEBUG_LOGGING) + log_link_debug(link, "Advertised route gateway %s is local to the link, ignoring route", + IN6_ADDR_TO_STRING(&gateway)); + return 0; + } + + r = sd_ndisc_router_route_get_preference(rt, &preference); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get default router preference from RA: %m"); + + r = sd_ndisc_router_get_timestamp(rt, CLOCK_BOOTTIME, ×tamp_usec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); + + r = route_new(&route); + if (r < 0) + return log_oom(); + + route->family = AF_INET6; + route->pref = preference; + route->gw.in6 = gateway; + route->gw_family = AF_INET6; + route->dst.in6 = dst; + route->dst_prefixlen = prefixlen; + route->lifetime_usec = sec_to_usec(lifetime_sec, timestamp_usec); + + r = ndisc_request_route(TAKE_PTR(route), link, rt); + if (r < 0) + return log_link_error_errno(link, r, "Could not request additional route: %m"); + + return 0; +} + +static void ndisc_rdnss_hash_func(const NDiscRDNSS *x, struct siphash *state) { + siphash24_compress(&x->address, sizeof(x->address), state); +} + +static int ndisc_rdnss_compare_func(const NDiscRDNSS *a, const NDiscRDNSS *b) { + return memcmp(&a->address, &b->address, sizeof(a->address)); +} + +DEFINE_PRIVATE_HASH_OPS_WITH_KEY_DESTRUCTOR( + ndisc_rdnss_hash_ops, + NDiscRDNSS, + ndisc_rdnss_hash_func, + ndisc_rdnss_compare_func, + free); + +static int ndisc_router_process_rdnss(Link *link, sd_ndisc_router *rt) { + usec_t lifetime_usec, timestamp_usec; + uint32_t lifetime_sec; + const struct in6_addr *a; + struct in6_addr router; + bool updated = false, logged_about_too_many = false; + int n, r; + + assert(link); + assert(link->network); + assert(rt); + + if (!link->network->ipv6_accept_ra_use_dns) + return 0; + + r = sd_ndisc_router_get_address(rt, &router); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get router address from RA: %m"); + + r = sd_ndisc_router_get_timestamp(rt, CLOCK_BOOTTIME, ×tamp_usec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); + + r = sd_ndisc_router_rdnss_get_lifetime(rt, &lifetime_sec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get RDNSS lifetime: %m"); + + lifetime_usec = sec_to_usec(lifetime_sec, timestamp_usec); + + n = sd_ndisc_router_rdnss_get_addresses(rt, &a); + if (n < 0) + return log_link_error_errno(link, n, "Failed to get RDNSS addresses: %m"); + + for (int j = 0; j < n; j++) { + _cleanup_free_ NDiscRDNSS *x = NULL; + NDiscRDNSS *rdnss, d = { + .address = a[j], + }; + + if (lifetime_usec == 0) { + /* The entry is outdated. */ + free(set_remove(link->ndisc_rdnss, &d)); + updated = true; + continue; + } + + rdnss = set_get(link->ndisc_rdnss, &d); + if (rdnss) { + rdnss->router = router; + rdnss->lifetime_usec = lifetime_usec; + continue; + } + + if (set_size(link->ndisc_rdnss) >= NDISC_RDNSS_MAX) { + if (!logged_about_too_many) + log_link_warning(link, "Too many RDNSS records per link. Only first %u records will be used.", NDISC_RDNSS_MAX); + logged_about_too_many = true; + continue; + } + + x = new(NDiscRDNSS, 1); + if (!x) + return log_oom(); + + *x = (NDiscRDNSS) { + .address = a[j], + .router = router, + .lifetime_usec = lifetime_usec, + }; + + r = set_ensure_consume(&link->ndisc_rdnss, &ndisc_rdnss_hash_ops, TAKE_PTR(x)); + if (r < 0) + return log_oom(); + assert(r > 0); + + updated = true; + } + + if (updated) + link_dirty(link); + + return 0; +} + +static void ndisc_dnssl_hash_func(const NDiscDNSSL *x, struct siphash *state) { + siphash24_compress_string(NDISC_DNSSL_DOMAIN(x), state); +} + +static int ndisc_dnssl_compare_func(const NDiscDNSSL *a, const NDiscDNSSL *b) { + return strcmp(NDISC_DNSSL_DOMAIN(a), NDISC_DNSSL_DOMAIN(b)); +} + +DEFINE_PRIVATE_HASH_OPS_WITH_KEY_DESTRUCTOR( + ndisc_dnssl_hash_ops, + NDiscDNSSL, + ndisc_dnssl_hash_func, + ndisc_dnssl_compare_func, + free); + +static int ndisc_router_process_dnssl(Link *link, sd_ndisc_router *rt) { + _cleanup_strv_free_ char **l = NULL; + usec_t lifetime_usec, timestamp_usec; + struct in6_addr router; + uint32_t lifetime_sec; + bool updated = false, logged_about_too_many = false; + int r; + + assert(link); + assert(link->network); + assert(rt); + + if (link->network->ipv6_accept_ra_use_domains == DHCP_USE_DOMAINS_NO) + return 0; + + r = sd_ndisc_router_get_address(rt, &router); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get router address from RA: %m"); + + r = sd_ndisc_router_get_timestamp(rt, CLOCK_BOOTTIME, ×tamp_usec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); + + r = sd_ndisc_router_dnssl_get_lifetime(rt, &lifetime_sec); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get DNSSL lifetime: %m"); + + lifetime_usec = sec_to_usec(lifetime_sec, timestamp_usec); + + r = sd_ndisc_router_dnssl_get_domains(rt, &l); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get DNSSL addresses: %m"); + + STRV_FOREACH(j, l) { + _cleanup_free_ NDiscDNSSL *s = NULL; + NDiscDNSSL *dnssl; + + s = malloc0(ALIGN(sizeof(NDiscDNSSL)) + strlen(*j) + 1); + if (!s) + return log_oom(); + + strcpy(NDISC_DNSSL_DOMAIN(s), *j); + + if (lifetime_usec == 0) { + /* The entry is outdated. */ + free(set_remove(link->ndisc_dnssl, s)); + updated = true; + continue; + } + + dnssl = set_get(link->ndisc_dnssl, s); + if (dnssl) { + dnssl->router = router; + dnssl->lifetime_usec = lifetime_usec; + continue; + } + + if (set_size(link->ndisc_dnssl) >= NDISC_DNSSL_MAX) { + if (!logged_about_too_many) + log_link_warning(link, "Too many DNSSL records per link. Only first %u records will be used.", NDISC_DNSSL_MAX); + logged_about_too_many = true; + continue; + } + + s->router = router; + s->lifetime_usec = lifetime_usec; + + r = set_ensure_consume(&link->ndisc_dnssl, &ndisc_dnssl_hash_ops, TAKE_PTR(s)); + if (r < 0) + return log_oom(); + assert(r > 0); + + updated = true; + } + + if (updated) + link_dirty(link); + + return 0; +} + +static int ndisc_router_process_options(Link *link, sd_ndisc_router *rt) { + int r; + + assert(link); + assert(link->network); + assert(rt); + + for (r = sd_ndisc_router_option_rewind(rt); ; r = sd_ndisc_router_option_next(rt)) { + uint8_t type; + + if (r < 0) + return log_link_error_errno(link, r, "Failed to iterate through options: %m"); + if (r == 0) /* EOF */ + return 0; + + r = sd_ndisc_router_option_get_type(rt, &type); + if (r < 0) + return log_link_error_errno(link, r, "Failed to get RA option type: %m"); + + switch (type) { + case SD_NDISC_OPTION_PREFIX_INFORMATION: + r = ndisc_router_process_prefix(link, rt); + break; + + case SD_NDISC_OPTION_ROUTE_INFORMATION: + r = ndisc_router_process_route(link, rt); + break; + + case SD_NDISC_OPTION_RDNSS: + r = ndisc_router_process_rdnss(link, rt); + break; + + case SD_NDISC_OPTION_DNSSL: + r = ndisc_router_process_dnssl(link, rt); + break; + } + if (r < 0 && r != -EBADMSG) + return r; + } +} + +static int ndisc_drop_outdated(Link *link, usec_t timestamp_usec) { + bool updated = false; + NDiscDNSSL *dnssl; + NDiscRDNSS *rdnss; + Address *address; + Route *route; + int r = 0, k; + + assert(link); + + /* If an address or friends is already assigned, but not valid anymore, then refuse to update it, + * and let's immediately remove it. + * See RFC4862, section 5.5.3.e. But the following logic is deviated from RFC4862 by honoring all + * valid lifetimes to improve the reaction of SLAAC to renumbering events. + * See draft-ietf-6man-slaac-renum-02, section 4.2. */ + + SET_FOREACH(route, link->routes) { + if (route->source != NETWORK_CONFIG_SOURCE_NDISC) + continue; + + if (route->lifetime_usec >= timestamp_usec) + continue; /* the route is still valid */ + + k = route_remove_and_drop(route); + if (k < 0) + r = log_link_warning_errno(link, k, "Failed to remove outdated SLAAC route, ignoring: %m"); + } + + SET_FOREACH(address, link->addresses) { + if (address->source != NETWORK_CONFIG_SOURCE_NDISC) + continue; + + if (address->lifetime_valid_usec >= timestamp_usec) + continue; /* the address is still valid */ + + k = address_remove_and_drop(address); + if (k < 0) + r = log_link_warning_errno(link, k, "Failed to remove outdated SLAAC address, ignoring: %m"); + } + + SET_FOREACH(rdnss, link->ndisc_rdnss) { + if (rdnss->lifetime_usec >= timestamp_usec) + continue; /* the DNS server is still valid */ + + free(set_remove(link->ndisc_rdnss, rdnss)); + updated = true; + } + + SET_FOREACH(dnssl, link->ndisc_dnssl) { + if (dnssl->lifetime_usec >= timestamp_usec) + continue; /* the DNS domain is still valid */ + + free(set_remove(link->ndisc_dnssl, dnssl)); + updated = true; + } + + if (updated) + link_dirty(link); + + return r; +} + +static int ndisc_setup_expire(Link *link); + +static int ndisc_expire_handler(sd_event_source *s, uint64_t usec, void *userdata) { + Link *link = ASSERT_PTR(userdata); + usec_t now_usec; + + assert(link->manager); + + assert_se(sd_event_now(link->manager->event, CLOCK_BOOTTIME, &now_usec) >= 0); + + (void) ndisc_drop_outdated(link, now_usec); + (void) ndisc_setup_expire(link); + return 0; +} + +static int ndisc_setup_expire(Link *link) { + usec_t lifetime_usec = USEC_INFINITY; + NDiscDNSSL *dnssl; + NDiscRDNSS *rdnss; + Address *address; + Route *route; + int r; + + assert(link); + assert(link->manager); + + SET_FOREACH(route, link->routes) { + if (route->source != NETWORK_CONFIG_SOURCE_NDISC) + continue; + + if (!route_exists(route)) + continue; + + lifetime_usec = MIN(lifetime_usec, route->lifetime_usec); + } + + SET_FOREACH(address, link->addresses) { + if (address->source != NETWORK_CONFIG_SOURCE_NDISC) + continue; + + if (!address_exists(address)) + continue; + + lifetime_usec = MIN(lifetime_usec, address->lifetime_valid_usec); + } + + SET_FOREACH(rdnss, link->ndisc_rdnss) + lifetime_usec = MIN(lifetime_usec, rdnss->lifetime_usec); + + SET_FOREACH(dnssl, link->ndisc_dnssl) + lifetime_usec = MIN(lifetime_usec, dnssl->lifetime_usec); + + if (lifetime_usec == USEC_INFINITY) + return 0; + + r = event_reset_time(link->manager->event, &link->ndisc_expire, CLOCK_BOOTTIME, + lifetime_usec, 0, ndisc_expire_handler, link, 0, "ndisc-expiration", true); + if (r < 0) + return log_link_warning_errno(link, r, "Failed to update expiration timer for ndisc: %m"); + + return 0; +} + +static int ndisc_start_dhcp6_client(Link *link, sd_ndisc_router *rt) { + int r; + + assert(link); + assert(link->network); + + switch (link->network->ipv6_accept_ra_start_dhcp6_client) { + case IPV6_ACCEPT_RA_START_DHCP6_CLIENT_NO: + return 0; + + case IPV6_ACCEPT_RA_START_DHCP6_CLIENT_YES: { + uint64_t flags; + + r = sd_ndisc_router_get_flags(rt, &flags); + if (r < 0) + return log_link_warning_errno(link, r, "Failed to get RA flags: %m"); + + if ((flags & (ND_RA_FLAG_MANAGED | ND_RA_FLAG_OTHER)) == 0) + return 0; + + /* (re)start DHCPv6 client in stateful or stateless mode according to RA flags. + * Note, if both "managed" and "other configuration" bits are set, then ignore + * "other configuration" bit. See RFC 4861. */ + r = dhcp6_start_on_ra(link, !(flags & ND_RA_FLAG_MANAGED)); + break; + } + case IPV6_ACCEPT_RA_START_DHCP6_CLIENT_ALWAYS: + /* When IPv6AcceptRA.DHCPv6Client=always, start dhcp6 client in solicit mode + * even if the router flags have neither M nor O flags. */ + r = dhcp6_start_on_ra(link, /* information_request = */ false); + break; + + default: + assert_not_reached(); + } + + if (r < 0) + return log_link_error_errno(link, r, "Could not acquire DHCPv6 lease on NDisc request: %m"); + + log_link_debug(link, "Acquiring DHCPv6 lease on NDisc request"); + return 0; +} + +static int ndisc_router_handler(Link *link, sd_ndisc_router *rt) { + struct in6_addr router; + usec_t timestamp_usec; + int r; + + assert(link); + assert(link->network); + assert(link->manager); + assert(rt); + + r = sd_ndisc_router_get_address(rt, &router); + if (r == -ENODATA) { + log_link_debug(link, "Received RA without router address, ignoring."); + return 0; + } + if (r < 0) + return log_link_error_errno(link, r, "Failed to get router address from RA: %m"); + + if (in6_prefix_is_filtered(&router, 128, link->network->ndisc_allow_listed_router, link->network->ndisc_deny_listed_router)) { + if (DEBUG_LOGGING) { + if (!set_isempty(link->network->ndisc_allow_listed_router)) + log_link_debug(link, "Router %s is not in allow list, ignoring.", IN6_ADDR_TO_STRING(&router)); + else + log_link_debug(link, "Router %s is in deny list, ignoring.", IN6_ADDR_TO_STRING(&router)); + } + return 0; + } + + r = sd_ndisc_router_get_timestamp(rt, CLOCK_BOOTTIME, ×tamp_usec); + if (r == -ENODATA) { + log_link_debug(link, "Received RA without timestamp, ignoring."); + return 0; + } + if (r < 0) + return r; + + r = ndisc_drop_outdated(link, timestamp_usec); + if (r < 0) + return r; + + r = ndisc_start_dhcp6_client(link, rt); + if (r < 0) + return r; + + r = ndisc_router_process_default(link, rt); + if (r < 0) + return r; + + r = ndisc_router_process_options(link, rt); + if (r < 0) + return r; + + r = ndisc_setup_expire(link); + if (r < 0) + return r; + + if (link->ndisc_messages == 0) + link->ndisc_configured = true; + else + log_link_debug(link, "Setting SLAAC addresses and router."); + + if (!link->ndisc_configured) + link_set_state(link, LINK_STATE_CONFIGURING); + + link_check_ready(link); + return 0; +} + +static void ndisc_handler(sd_ndisc *nd, sd_ndisc_event_t event, sd_ndisc_router *rt, void *userdata) { + Link *link = ASSERT_PTR(userdata); + int r; + + if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) + return; + + switch (event) { + + case SD_NDISC_EVENT_ROUTER: + r = ndisc_router_handler(link, rt); + if (r < 0 && r != -EBADMSG) { + link_enter_failed(link); + return; + } + break; + + case SD_NDISC_EVENT_TIMEOUT: + log_link_debug(link, "NDisc handler get timeout event"); + if (link->ndisc_messages == 0) { + link->ndisc_configured = true; + link_check_ready(link); + } + break; + default: + assert_not_reached(); + } +} + +static int ndisc_configure(Link *link) { + int r; + + assert(link); + + if (!link_ipv6_accept_ra_enabled(link)) + return 0; + + if (link->ndisc) + return -EBUSY; /* Already configured. */ + + r = sd_ndisc_new(&link->ndisc); + if (r < 0) + return r; + + r = sd_ndisc_attach_event(link->ndisc, link->manager->event, 0); + if (r < 0) + return r; + + if (link->hw_addr.length == ETH_ALEN) { + r = sd_ndisc_set_mac(link->ndisc, &link->hw_addr.ether); + if (r < 0) + return r; + } + + r = sd_ndisc_set_ifindex(link->ndisc, link->ifindex); + if (r < 0) + return r; + + r = sd_ndisc_set_callback(link->ndisc, ndisc_handler, link); + if (r < 0) + return r; + + return 0; +} + +int ndisc_start(Link *link) { + int r; + + assert(link); + + if (!link->ndisc || !link->dhcp6_client) + return 0; + + if (!link_has_carrier(link)) + return 0; + + if (in6_addr_is_null(&link->ipv6ll_address)) + return 0; + + log_link_debug(link, "Discovering IPv6 routers"); + + r = sd_ndisc_start(link->ndisc); + if (r < 0) + return r; + + return 1; +} + +static int ndisc_process_request(Request *req, Link *link, void *userdata) { + int r; + + assert(link); + + if (!link_is_ready_to_configure(link, /* allow_unmanaged = */ false)) + return 0; + + r = ndisc_configure(link); + if (r < 0) + return log_link_warning_errno(link, r, "Failed to configure IPv6 Router Discovery: %m"); + + r = ndisc_start(link); + if (r < 0) + return log_link_warning_errno(link, r, "Failed to start IPv6 Router Discovery: %m"); + + log_link_debug(link, "IPv6 Router Discovery is configured%s.", + r > 0 ? " and started" : ""); + return 1; +} + +int link_request_ndisc(Link *link) { + int r; + + assert(link); + + if (!link_ipv6_accept_ra_enabled(link)) + return 0; + + if (link->ndisc) + return 0; + + r = link_queue_request(link, REQUEST_TYPE_NDISC, ndisc_process_request, NULL); + if (r < 0) + return log_link_warning_errno(link, r, "Failed to request configuring of the IPv6 Router Discovery: %m"); + + log_link_debug(link, "Requested configuring of the IPv6 Router Discovery."); + return 0; +} + +int ndisc_stop(Link *link) { + assert(link); + + link->ndisc_expire = sd_event_source_disable_unref(link->ndisc_expire); + + return sd_ndisc_stop(link->ndisc); +} + + +void ndisc_flush(Link *link) { + assert(link); + + /* Removes all RDNSS and DNSSL entries, without exception */ + + link->ndisc_rdnss = set_free(link->ndisc_rdnss); + link->ndisc_dnssl = set_free(link->ndisc_dnssl); +} + +static const char* const ipv6_accept_ra_start_dhcp6_client_table[_IPV6_ACCEPT_RA_START_DHCP6_CLIENT_MAX] = { + [IPV6_ACCEPT_RA_START_DHCP6_CLIENT_NO] = "no", + [IPV6_ACCEPT_RA_START_DHCP6_CLIENT_ALWAYS] = "always", + [IPV6_ACCEPT_RA_START_DHCP6_CLIENT_YES] = "yes", +}; + +DEFINE_PRIVATE_STRING_TABLE_LOOKUP_FROM_STRING_WITH_BOOLEAN(ipv6_accept_ra_start_dhcp6_client, IPv6AcceptRAStartDHCP6Client, IPV6_ACCEPT_RA_START_DHCP6_CLIENT_YES); + +DEFINE_CONFIG_PARSE_ENUM(config_parse_ipv6_accept_ra_use_domains, dhcp_use_domains, DHCPUseDomains, + "Failed to parse UseDomains= setting"); +DEFINE_CONFIG_PARSE_ENUM(config_parse_ipv6_accept_ra_start_dhcp6_client, ipv6_accept_ra_start_dhcp6_client, IPv6AcceptRAStartDHCP6Client, + "Failed to parse DHCPv6Client= setting"); -- cgit v1.2.3