Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 892 insertions, 0 deletions

diff --git a/src/network/networkd-dhcp6.c b/src/network/networkd-dhcp6.c
new file mode 100644
index 0000000..f499d03
--- /dev/null
+++ b/src/network/networkd-dhcp6.c
@@ -0,0 +1,892 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/***
+  Copyright © 2014 Intel Corporation. All rights reserved.
+***/
+
+#include "dhcp6-client-internal.h"
+#include "dhcp6-lease-internal.h"
+#include "hashmap.h"
+#include "hostname-setup.h"
+#include "hostname-util.h"
+#include "networkd-address.h"
+#include "networkd-dhcp-prefix-delegation.h"
+#include "networkd-dhcp6-bus.h"
+#include "networkd-dhcp6.h"
+#include "networkd-link.h"
+#include "networkd-manager.h"
+#include "networkd-queue.h"
+#include "networkd-route.h"
+#include "networkd-state-file.h"
+#include "string-table.h"
+#include "string-util.h"
+
+bool link_dhcp6_with_address_enabled(Link *link) {
+        if (!link_dhcp6_enabled(link))
+                return false;
+
+        return link->network->dhcp6_use_address;
+}
+
+static DHCP6ClientStartMode link_get_dhcp6_client_start_mode(Link *link) {
+        assert(link);
+
+        if (!link->network)
+                return DHCP6_CLIENT_START_MODE_NO;
+
+        /* When WithoutRA= is explicitly specified, then honor it. */
+        if (link->network->dhcp6_client_start_mode >= 0)
+                return link->network->dhcp6_client_start_mode;
+
+        /* When this interface itself is an uplink interface, then start dhcp6 client in solicit mode. */
+        if (dhcp_pd_is_uplink(link, link, /* accept_auto = */ false))
+                return DHCP6_CLIENT_START_MODE_SOLICIT;
+
+        /* Otherwise, start dhcp6 client when RA is received. */
+        return DHCP6_CLIENT_START_MODE_NO;
+}
+
+static int dhcp6_remove(Link *link, bool only_marked) {
+        Address *address;
+        Route *route;
+        int k, r = 0;
+
+        assert(link);
+
+        if (!only_marked)
+                link->dhcp6_configured = false;
+
+        SET_FOREACH(route, link->routes) {
+                if (route->source != NETWORK_CONFIG_SOURCE_DHCP6)
+                        continue;
+                if (only_marked && !route_is_marked(route))
+                        continue;
+
+                k = route_remove(route);
+                if (k < 0)
+                        r = k;
+
+                route_cancel_request(route, link);
+        }
+
+        SET_FOREACH(address, link->addresses) {
+                if (address->source != NETWORK_CONFIG_SOURCE_DHCP6)
+                        continue;
+                if (only_marked && !address_is_marked(address))
+                        continue;
+
+                k = address_remove_and_drop(address);
+                if (k < 0)
+                        r = k;
+        }
+
+        return r;
+}
+
+static int dhcp6_address_ready_callback(Address *address) {
+        Address *a;
+
+        assert(address);
+        assert(address->link);
+
+        SET_FOREACH(a, address->link->addresses)
+                if (a->source == NETWORK_CONFIG_SOURCE_DHCP6)
+                        a->callback = NULL;
+
+        return dhcp6_check_ready(address->link);
+}
+
+int dhcp6_check_ready(Link *link) {
+        int r;
+
+        assert(link);
+        assert(link->network);
+
+        if (link->dhcp6_messages > 0) {
+                log_link_debug(link, "%s(): DHCPv6 addresses and routes are not set.", __func__);
+                return 0;
+        }
+
+        if (link->network->dhcp6_use_address &&
+            sd_dhcp6_lease_has_address(link->dhcp6_lease) &&
+            !link_check_addresses_ready(link, NETWORK_CONFIG_SOURCE_DHCP6)) {
+                Address *address;
+
+                SET_FOREACH(address, link->addresses)
+                        if (address->source == NETWORK_CONFIG_SOURCE_DHCP6)
+                                address->callback = dhcp6_address_ready_callback;
+
+                log_link_debug(link, "%s(): no DHCPv6 address is ready.", __func__);
+                return 0;
+        }
+
+        link->dhcp6_configured = true;
+        log_link_debug(link, "DHCPv6 addresses and routes set.");
+
+        r = dhcp6_remove(link, /* only_marked = */ true);
+        if (r < 0)
+                return r;
+
+        link_check_ready(link);
+        return 0;
+}
+
+static int dhcp6_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 DHCPv6 address");
+        if (r <= 0)
+                return r;
+
+        r = dhcp6_check_ready(link);
+        if (r < 0)
+                link_enter_failed(link);
+
+        return 1;
+}
+
+static int verify_dhcp6_address(Link *link, const Address *address) {
+        bool by_ndisc = false;
+        Address *existing;
+        int log_level;
+
+        assert(link);
+        assert(address);
+        assert(address->family == AF_INET6);
+
+        const char *pretty = IN6_ADDR_TO_STRING(&address->in_addr.in6);
+
+        if (address_get_harder(link, address, &existing) < 0) {
+                /* New address. */
+                log_level = LOG_INFO;
+                goto simple_log;
+        } else
+                log_level = LOG_DEBUG;
+
+        if (address->prefixlen == existing->prefixlen)
+                /* Currently, only conflict in prefix length is reported. */
+                goto simple_log;
+
+        if (existing->source == NETWORK_CONFIG_SOURCE_NDISC)
+                by_ndisc = true;
+
+        log_link_warning(link, "Ignoring DHCPv6 address %s/%u (valid %s, preferred %s) which conflicts with %s/%u%s.",
+                         pretty, address->prefixlen,
+                         FORMAT_LIFETIME(address->lifetime_valid_usec),
+                         FORMAT_LIFETIME(address->lifetime_preferred_usec),
+                         pretty, existing->prefixlen,
+                         by_ndisc ? " assigned by NDisc" : "");
+        if (by_ndisc)
+                log_link_warning(link, "Hint: use IPv6Token= setting to change the address generated by NDisc or set UseAutonomousPrefix=no.");
+
+        return -EEXIST;
+
+simple_log:
+        log_link_full(link, log_level, "DHCPv6 address %s/%u (valid %s, preferred %s)",
+                      pretty, address->prefixlen,
+                      FORMAT_LIFETIME(address->lifetime_valid_usec),
+                      FORMAT_LIFETIME(address->lifetime_preferred_usec));
+        return 0;
+}
+
+static int dhcp6_request_address(
+                Link *link,
+                const struct in6_addr *server_address,
+                const struct in6_addr *ip6_addr,
+                usec_t lifetime_preferred_usec,
+                usec_t lifetime_valid_usec) {
+
+        _cleanup_(address_freep) Address *addr = NULL;
+        Address *existing;
+        int r;
+
+        r = address_new(&addr);
+        if (r < 0)
+                return log_oom();
+
+        addr->source = NETWORK_CONFIG_SOURCE_DHCP6;
+        addr->provider.in6 = *server_address;
+        addr->family = AF_INET6;
+        addr->in_addr.in6 = *ip6_addr;
+        addr->flags = IFA_F_NOPREFIXROUTE;
+        addr->prefixlen = 128;
+        addr->lifetime_preferred_usec = lifetime_preferred_usec;
+        addr->lifetime_valid_usec = lifetime_valid_usec;
+
+        if (verify_dhcp6_address(link, addr) < 0)
+                return 0;
+
+        r = free_and_strdup_warn(&addr->netlabel, link->network->dhcp6_netlabel);
+        if (r < 0)
+                return r;
+
+        if (address_get(link, addr, &existing) < 0)
+                link->dhcp6_configured = false;
+        else
+                address_unmark(existing);
+
+        r = link_request_address(link, addr, &link->dhcp6_messages,
+                                 dhcp6_address_handler, NULL);
+        if (r < 0)
+                return log_link_error_errno(link, r, "Failed to request DHCPv6 address %s/128: %m",
+                                            IN6_ADDR_TO_STRING(ip6_addr));
+        return 0;
+}
+
+static int dhcp6_address_acquired(Link *link) {
+        struct in6_addr server_address;
+        int r;
+
+        assert(link);
+        assert(link->network);
+        assert(link->dhcp6_lease);
+
+        if (!link->network->dhcp6_use_address)
+                return 0;
+
+        r = sd_dhcp6_lease_get_server_address(link->dhcp6_lease, &server_address);
+        if (r < 0)
+                return log_link_warning_errno(link, r, "Failed to get server address of DHCPv6 lease: %m");
+
+        FOREACH_DHCP6_ADDRESS(link->dhcp6_lease) {
+                usec_t lifetime_preferred_usec, lifetime_valid_usec;
+                struct in6_addr ip6_addr;
+
+                r = sd_dhcp6_lease_get_address(link->dhcp6_lease, &ip6_addr);
+                if (r < 0)
+                        return r;
+
+                r = sd_dhcp6_lease_get_address_lifetime_timestamp(link->dhcp6_lease, CLOCK_BOOTTIME,
+                                                                  &lifetime_preferred_usec, &lifetime_valid_usec);
+                if (r < 0)
+                        return r;
+
+                r = dhcp6_request_address(link, &server_address, &ip6_addr,
+                                          lifetime_preferred_usec,
+                                          lifetime_valid_usec);
+                if (r < 0)
+                        return r;
+        }
+
+        if (link->network->dhcp6_use_hostname) {
+                const char *dhcpname = NULL;
+                _cleanup_free_ char *hostname = NULL;
+
+                (void) sd_dhcp6_lease_get_fqdn(link->dhcp6_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);
+                }
+        }
+
+        return 0;
+}
+
+static int dhcp6_lease_ip_acquired(sd_dhcp6_client *client, Link *link) {
+        _cleanup_(sd_dhcp6_lease_unrefp) sd_dhcp6_lease *lease_old = NULL;
+        sd_dhcp6_lease *lease;
+        int r;
+
+        link_mark_addresses(link, NETWORK_CONFIG_SOURCE_DHCP6);
+        link_mark_routes(link, NETWORK_CONFIG_SOURCE_DHCP6);
+
+        r = sd_dhcp6_client_get_lease(client, &lease);
+        if (r < 0)
+                return log_link_error_errno(link, r, "Failed to get DHCPv6 lease: %m");
+
+        lease_old = TAKE_PTR(link->dhcp6_lease);
+        link->dhcp6_lease = sd_dhcp6_lease_ref(lease);
+
+        r = dhcp6_address_acquired(link);
+        if (r < 0)
+                return r;
+
+        if (sd_dhcp6_lease_has_pd_prefix(lease)) {
+                r = dhcp6_pd_prefix_acquired(link);
+                if (r < 0)
+                        return r;
+        } else if (sd_dhcp6_lease_has_pd_prefix(lease_old))
+                /* When we had PD prefixes but not now, we need to remove them. */
+                dhcp_pd_prefix_lost(link);
+
+        if (link->dhcp6_messages == 0) {
+                link->dhcp6_configured = true;
+
+                r = dhcp6_remove(link, /* only_marked = */ true);
+                if (r < 0)
+                        return r;
+        } else
+                log_link_debug(link, "Setting DHCPv6 addresses and routes");
+
+        if (!link->dhcp6_configured)
+                link_set_state(link, LINK_STATE_CONFIGURING);
+
+        link_check_ready(link);
+        return 0;
+}
+
+static int dhcp6_lease_information_acquired(sd_dhcp6_client *client, Link *link) {
+        sd_dhcp6_lease *lease;
+        int r;
+
+        assert(client);
+        assert(link);
+
+        r = sd_dhcp6_client_get_lease(client, &lease);
+        if (r < 0)
+                return log_link_error_errno(link, r, "Failed to get DHCPv6 lease: %m");
+
+        unref_and_replace_full(link->dhcp6_lease, lease, sd_dhcp6_lease_ref, sd_dhcp6_lease_unref);
+
+        link_dirty(link);
+        return 0;
+}
+
+static int dhcp6_lease_lost(Link *link) {
+        int r;
+
+        assert(link);
+        assert(link->manager);
+
+        log_link_info(link, "DHCPv6 lease lost");
+
+        if (sd_dhcp6_lease_has_pd_prefix(link->dhcp6_lease))
+                dhcp_pd_prefix_lost(link);
+
+        link->dhcp6_lease = sd_dhcp6_lease_unref(link->dhcp6_lease);
+
+        r = dhcp6_remove(link, /* only_marked = */ false);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
+static void dhcp6_handler(sd_dhcp6_client *client, int event, void *userdata) {
+        Link *link = ASSERT_PTR(userdata);
+        int r = 0;
+
+        assert(link->network);
+
+        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
+                return;
+
+        switch (event) {
+        case SD_DHCP6_CLIENT_EVENT_STOP:
+        case SD_DHCP6_CLIENT_EVENT_RESEND_EXPIRE:
+        case SD_DHCP6_CLIENT_EVENT_RETRANS_MAX:
+                r = dhcp6_lease_lost(link);
+                break;
+
+        case SD_DHCP6_CLIENT_EVENT_IP_ACQUIRE:
+                r = dhcp6_lease_ip_acquired(client, link);
+                break;
+
+        case SD_DHCP6_CLIENT_EVENT_INFORMATION_REQUEST:
+                r = dhcp6_lease_information_acquired(client, link);
+                break;
+
+        default:
+                if (event < 0)
+                        log_link_warning_errno(link, event, "DHCPv6 error, ignoring: %m");
+                else
+                        log_link_warning(link, "DHCPv6 unknown event: %d", event);
+        }
+        if (r < 0)
+                link_enter_failed(link);
+}
+
+int dhcp6_start_on_ra(Link *link, bool information_request) {
+        int r;
+
+        assert(link);
+        assert(link->dhcp6_client);
+        assert(link->network);
+        assert(in6_addr_is_link_local(&link->ipv6ll_address));
+
+        if (link_get_dhcp6_client_start_mode(link) != DHCP6_CLIENT_START_MODE_NO)
+                /* When WithoutRA= is specified, then the DHCPv6 client should be already running in
+                 * the requested mode. Hence, ignore the requests by RA. */
+                return 0;
+
+        r = sd_dhcp6_client_is_running(link->dhcp6_client);
+        if (r < 0)
+                return r;
+
+        if (r > 0) {
+                int inf_req;
+
+                r = sd_dhcp6_client_get_information_request(link->dhcp6_client, &inf_req);
+                if (r < 0)
+                        return r;
+
+                if (inf_req == information_request)
+                        /* The client is already running in the requested mode. */
+                        return 0;
+
+                if (!inf_req) {
+                        log_link_debug(link,
+                                       "The DHCPv6 client is already running in the managed mode, "
+                                       "refusing to start the client in the information requesting mode.");
+                        return 0;
+                }
+
+                log_link_debug(link,
+                               "The DHCPv6 client is running in the information requesting mode. "
+                               "Restarting the client in the managed mode.");
+
+                r = sd_dhcp6_client_stop(link->dhcp6_client);
+                if (r < 0)
+                        return r;
+        } else {
+                r = sd_dhcp6_client_set_local_address(link->dhcp6_client, &link->ipv6ll_address);
+                if (r < 0)
+                        return r;
+        }
+
+        r = sd_dhcp6_client_set_information_request(link->dhcp6_client, information_request);
+        if (r < 0)
+                return r;
+
+        r = sd_dhcp6_client_start(link->dhcp6_client);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
+int dhcp6_start(Link *link) {
+        DHCP6ClientStartMode start_mode;
+        int r;
+
+        assert(link);
+        assert(link->network);
+
+        if (!link->dhcp6_client)
+                return 0;
+
+        if (!link_dhcp6_enabled(link))
+                return 0;
+
+        if (!link_has_carrier(link))
+                return 0;
+
+        if (sd_dhcp6_client_is_running(link->dhcp6_client) > 0)
+                return 0;
+
+        if (!in6_addr_is_link_local(&link->ipv6ll_address)) {
+                log_link_debug(link, "IPv6 link-local address is not set, delaying to start DHCPv6 client.");
+                return 0;
+        }
+
+        r = sd_dhcp6_client_set_local_address(link->dhcp6_client, &link->ipv6ll_address);
+        if (r < 0)
+                return r;
+
+        start_mode = link_get_dhcp6_client_start_mode(link);
+        if (start_mode == DHCP6_CLIENT_START_MODE_NO)
+                return 0;
+
+        r = sd_dhcp6_client_set_information_request(link->dhcp6_client,
+                                                    start_mode == DHCP6_CLIENT_START_MODE_INFORMATION_REQUEST);
+        if (r < 0)
+                return r;
+
+        r = sd_dhcp6_client_start(link->dhcp6_client);
+        if (r < 0)
+                return r;
+
+        return 1;
+}
+
+static int dhcp6_set_hostname(sd_dhcp6_client *client, Link *link) {
+        _cleanup_free_ char *hostname = NULL;
+        const char *hn;
+        int r;
+
+        assert(link);
+
+        if (!link->network->dhcp6_send_hostname)
+                hn = NULL;
+        else if (link->network->dhcp6_hostname)
+                hn = link->network->dhcp6_hostname;
+        else {
+                r = gethostname_strict(&hostname);
+                if (r < 0 && r != -ENXIO) /* ENXIO: no hostname set or hostname is "localhost" */
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to get hostname: %m");
+
+                hn = hostname;
+        }
+
+        r = sd_dhcp6_client_set_fqdn(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, "DHCPv6 CLIENT: Failed to set hostname from kernel hostname, ignoring: %m");
+        else if (r < 0)
+                return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set hostname: %m");
+
+        return 0;
+}
+
+static int dhcp6_set_identifier(Link *link, sd_dhcp6_client *client) {
+        const DUID *duid;
+        int r;
+
+        assert(link);
+        assert(link->network);
+        assert(client);
+
+        r = sd_dhcp6_client_set_mac(client, link->hw_addr.bytes, link->hw_addr.length, link->iftype);
+        if (r < 0)
+                return r;
+
+        if (link->network->dhcp6_iaid_set) {
+                r = sd_dhcp6_client_set_iaid(client, link->network->dhcp6_iaid);
+                if (r < 0)
+                        return r;
+        }
+
+        duid = link_get_dhcp6_duid(link);
+
+        if (duid->raw_data_len == 0)
+                switch (duid->type) {
+                case DUID_TYPE_LLT:
+                        r = sd_dhcp6_client_set_duid_llt(client, duid->llt_time);
+                        break;
+                case DUID_TYPE_LL:
+                        r = sd_dhcp6_client_set_duid_ll(client);
+                        break;
+                case DUID_TYPE_EN:
+                        r = sd_dhcp6_client_set_duid_en(client);
+                        break;
+                case DUID_TYPE_UUID:
+                        r = sd_dhcp6_client_set_duid_uuid(client);
+                        break;
+                default:
+                        r = sd_dhcp6_client_set_duid_raw(client, duid->type, NULL, 0);
+                }
+        else
+                r = sd_dhcp6_client_set_duid_raw(client, duid->type, duid->raw_data, duid->raw_data_len);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
+static int dhcp6_configure(Link *link) {
+        _cleanup_(sd_dhcp6_client_unrefp) sd_dhcp6_client *client = NULL;
+        sd_dhcp6_option *vendor_option;
+        sd_dhcp6_option *send_option;
+        void *request_options;
+        int r;
+
+        assert(link);
+        assert(link->network);
+
+        if (link->dhcp6_client)
+                return log_link_debug_errno(link, SYNTHETIC_ERRNO(EBUSY), "DHCPv6 client is already configured.");
+
+        r = sd_dhcp6_client_new(&client);
+        if (r == -ENOMEM)
+                return log_oom_debug();
+        if (r < 0)
+                return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to create DHCPv6 client: %m");
+
+        r = sd_dhcp6_client_attach_event(client, link->manager->event, 0);
+        if (r < 0)
+                return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to attach event: %m");
+
+        r = sd_dhcp6_client_attach_device(client, link->dev);
+        if (r < 0)
+                return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to attach device: %m");
+
+        r = dhcp6_set_identifier(link, client);
+        if (r < 0)
+                return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set identifier: %m");
+
+        ORDERED_HASHMAP_FOREACH(send_option, link->network->dhcp6_client_send_options) {
+                r = sd_dhcp6_client_add_option(client, send_option);
+                if (r == -EEXIST)
+                        continue;
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set option: %m");
+        }
+
+        r = dhcp6_set_hostname(client, link);
+        if (r < 0)
+                return r;
+
+        r = sd_dhcp6_client_set_ifindex(client, link->ifindex);
+        if (r < 0)
+                return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set ifindex: %m");
+
+        if (link->network->dhcp6_mudurl) {
+                r = sd_dhcp6_client_set_request_mud_url(client, link->network->dhcp6_mudurl);
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set MUD URL: %m");
+        }
+
+        if (link->network->dhcp6_use_dns) {
+                r = sd_dhcp6_client_set_request_option(client, SD_DHCP6_OPTION_DNS_SERVER);
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to request DNS servers: %m");
+        }
+
+        if (link->network->dhcp6_use_domains > 0) {
+                r = sd_dhcp6_client_set_request_option(client, SD_DHCP6_OPTION_DOMAIN);
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to request domains: %m");
+        }
+
+        if (link->network->dhcp6_use_captive_portal > 0) {
+                r = sd_dhcp6_client_set_request_option(client, SD_DHCP6_OPTION_CAPTIVE_PORTAL);
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to request captive portal: %m");
+        }
+
+        if (link->network->dhcp6_use_ntp) {
+                r = sd_dhcp6_client_set_request_option(client, SD_DHCP6_OPTION_NTP_SERVER);
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to request NTP servers: %m");
+
+                /* If the server does not provide NTP servers, then we fallback to use SNTP servers. */
+                r = sd_dhcp6_client_set_request_option(client, SD_DHCP6_OPTION_SNTP_SERVER);
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to request SNTP servers: %m");
+        }
+
+        SET_FOREACH(request_options, link->network->dhcp6_request_options) {
+                uint32_t option = PTR_TO_UINT32(request_options);
+
+                r = sd_dhcp6_client_set_request_option(client, option);
+                if (r == -EEXIST) {
+                        log_link_debug(link, "DHCPv6 CLIENT: Failed to set request flag for '%u' already exists, ignoring.", option);
+                        continue;
+                }
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set request flag for '%u': %m", option);
+        }
+
+        if (link->network->dhcp6_user_class) {
+                r = sd_dhcp6_client_set_request_user_class(client, link->network->dhcp6_user_class);
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set user class: %m");
+        }
+
+        if (link->network->dhcp6_vendor_class) {
+                r = sd_dhcp6_client_set_request_vendor_class(client, link->network->dhcp6_vendor_class);
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set vendor class: %m");
+        }
+
+        ORDERED_HASHMAP_FOREACH(vendor_option, link->network->dhcp6_client_send_vendor_options) {
+                r = sd_dhcp6_client_add_vendor_option(client, vendor_option);
+                if (r == -EEXIST)
+                        continue;
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set vendor option: %m");
+        }
+
+        r = sd_dhcp6_client_set_callback(client, dhcp6_handler, link);
+        if (r < 0)
+                return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set callback: %m");
+
+        r = dhcp6_client_set_state_callback(client, dhcp6_client_callback_bus, link);
+        if (r < 0)
+                return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set state change callback: %m");
+
+        r = sd_dhcp6_client_set_prefix_delegation(client, link->network->dhcp6_use_pd_prefix);
+        if (r < 0)
+                return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to %s requesting prefixes to be delegated: %m",
+                                            enable_disable(link->network->dhcp6_use_pd_prefix));
+
+        /* Even if UseAddress=no, we need to request IA_NA, as the dhcp6 client may be started in solicit mode. */
+        r = sd_dhcp6_client_set_address_request(client, link->network->dhcp6_use_pd_prefix ? link->network->dhcp6_use_address : true);
+        if (r < 0)
+                return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to %s requesting address: %m",
+                                            enable_disable(link->network->dhcp6_use_address));
+
+        if (link->network->dhcp6_pd_prefix_length > 0) {
+                r = sd_dhcp6_client_set_prefix_delegation_hint(client,
+                                                               link->network->dhcp6_pd_prefix_length,
+                                                               &link->network->dhcp6_pd_prefix_hint);
+                if (r < 0)
+                        return log_link_debug_errno(link, r, "DHCPv6 CLIENT: Failed to set prefix delegation hint: %m");
+        }
+
+        r = sd_dhcp6_client_set_rapid_commit(client, link->network->dhcp6_use_rapid_commit);
+        if (r < 0)
+                return log_link_debug_errno(link, r,
+                                            "DHCPv6 CLIENT: Failed to %s rapid commit: %m",
+                                            enable_disable(link->network->dhcp6_use_rapid_commit));
+
+        r = sd_dhcp6_client_set_send_release(client, link->network->dhcp6_send_release);
+        if (r < 0)
+                return log_link_debug_errno(link, r,
+                                            "DHCPv6 CLIENT: Failed to %s sending release message on stop: %m",
+                                            enable_disable(link->network->dhcp6_send_release));
+
+        link->dhcp6_client = TAKE_PTR(client);
+
+        return 0;
+}
+
+int dhcp6_update_mac(Link *link) {
+        bool restart;
+        int r;
+
+        assert(link);
+
+        if (!link->dhcp6_client)
+                return 0;
+
+        restart = sd_dhcp6_client_is_running(link->dhcp6_client) > 0;
+
+        if (restart) {
+                r = sd_dhcp6_client_stop(link->dhcp6_client);
+                if (r < 0)
+                        return r;
+        }
+
+        r = dhcp6_set_identifier(link, link->dhcp6_client);
+        if (r < 0)
+                return r;
+
+        if (restart) {
+                r = sd_dhcp6_client_start(link->dhcp6_client);
+                if (r < 0)
+                        return log_link_warning_errno(link, r, "Could not restart DHCPv6 client: %m");
+        }
+
+        return 0;
+}
+
+static int dhcp6_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 = dhcp_configure_duid(link, link_get_dhcp6_duid(link));
+        if (r <= 0)
+                return r;
+
+        r = dhcp6_configure(link);
+        if (r < 0)
+                return log_link_warning_errno(link, r, "Failed to configure DHCPv6 client: %m");
+
+        r = ndisc_start(link);
+        if (r < 0)
+                return log_link_warning_errno(link, r, "Failed to start IPv6 Router Discovery: %m");
+
+        r = dhcp6_start(link);
+        if (r < 0)
+                return log_link_warning_errno(link, r, "Failed to start DHCPv6 client: %m");
+
+        log_link_debug(link, "DHCPv6 client is configured%s.",
+                       r > 0 ? ", acquiring DHCPv6 lease" : "");
+        return 1;
+}
+
+int link_request_dhcp6_client(Link *link) {
+        int r;
+
+        assert(link);
+
+        if (!link_dhcp6_enabled(link) && !link_ipv6_accept_ra_enabled(link))
+                return 0;
+
+        if (link->dhcp6_client)
+                return 0;
+
+        r = link_queue_request(link, REQUEST_TYPE_DHCP6_CLIENT, dhcp6_process_request, NULL);
+        if (r < 0)
+                return log_link_warning_errno(link, r, "Failed to request configuring of the DHCPv6 client: %m");
+
+        log_link_debug(link, "Requested configuring of the DHCPv6 client.");
+        return 0;
+}
+
+int link_serialize_dhcp6_client(Link *link, FILE *f) {
+        _cleanup_free_ char *duid = NULL;
+        uint32_t iaid;
+        int r;
+
+        assert(link);
+
+        if (!link->dhcp6_client)
+                return 0;
+
+        r = sd_dhcp6_client_get_iaid(link->dhcp6_client, &iaid);
+        if (r >= 0)
+                fprintf(f, "DHCP6_CLIENT_IAID=0x%x\n", iaid);
+
+        r = sd_dhcp6_client_duid_as_string(link->dhcp6_client, &duid);
+        if (r >= 0)
+                fprintf(f, "DHCP6_CLIENT_DUID=%s\n", duid);
+
+        return 0;
+}
+
+int config_parse_dhcp6_pd_prefix_hint(
+                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 = ASSERT_PTR(userdata);
+        union in_addr_union u;
+        unsigned char prefixlen;
+        int r;
+
+        assert(filename);
+        assert(lvalue);
+        assert(rvalue);
+
+        r = in_addr_prefix_from_string(rvalue, AF_INET6, &u, &prefixlen);
+        if (r < 0) {
+                log_syntax(unit, LOG_WARNING, filename, line, r,
+                           "Failed to parse %s=%s, ignoring assignment.", lvalue, rvalue);
+                return 0;
+        }
+
+        if (prefixlen < 1 || prefixlen > 128) {
+                log_syntax(unit, LOG_WARNING, filename, line, 0,
+                           "Invalid prefix length in %s=%s, ignoring assignment.", lvalue, rvalue);
+                return 0;
+        }
+
+        network->dhcp6_pd_prefix_hint = u.in6;
+        network->dhcp6_pd_prefix_length = prefixlen;
+
+        return 0;
+}
+
+DEFINE_CONFIG_PARSE_ENUM(config_parse_dhcp6_client_start_mode, dhcp6_client_start_mode, DHCP6ClientStartMode,
+                         "Failed to parse WithoutRA= setting");
+
+static const char* const dhcp6_client_start_mode_table[_DHCP6_CLIENT_START_MODE_MAX] = {
+        [DHCP6_CLIENT_START_MODE_NO]                  = "no",
+        [DHCP6_CLIENT_START_MODE_INFORMATION_REQUEST] = "information-request",
+        [DHCP6_CLIENT_START_MODE_SOLICIT]             = "solicit",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(dhcp6_client_start_mode, DHCP6ClientStartMode);