Merge pull request #17357 from yuwata/network-dhcp6-pd-announce-17353

network: add an option to control announcement of delegated prefix

12 files changed, 294 insertions, 170 deletions

diff --git a/man/systemd.network.xml b/man/systemd.network.xml
index 5307a508d3..1eb8274e83 100644
--- a/man/systemd.network.xml
+++ b/man/systemd.network.xml
@@ -810,18 +810,24 @@ IPv6Token=prefixstable:2002:da8:1::</programlisting></para>
         </para></listitem>
         </varlistentry>
         <varlistentry>
-          <term><varname>IPv6PrefixDelegation=</varname></term>
-          <listitem><para>Whether to enable or disable Router Advertisement sending on a link.  Allowed
-          values are <literal>static</literal> which distributes prefixes as defined in the
-          [IPv6PrefixDelegation] and any [IPv6Prefix] sections, <literal>dhcpv6</literal> which requests
-          prefixes using a DHCPv6 client configured for another link and any values configured in the
-          [IPv6PrefixDelegation] section while ignoring all static prefix configuration sections,
-          <literal>yes</literal> which uses both static configuration and DHCPv6, and
-          <literal>false</literal> which turns off IPv6 prefix delegation altogether. Defaults to
-          <literal>false</literal>. See the [IPv6PrefixDelegation] and the [IPv6Prefix] sections for more
+          <term><varname>IPv6SendRA=</varname></term>
+          <listitem><para>Whether to enable or disable Router Advertisement sending on a link. Takes a
+          boolean value. When enabled, prefixes configured in [IPv6Prefix] sections and routes
+          configured in [IPv6RoutePrefix] sections are distributed as defined in the [IPv6SendRA]
+          section. If <varname>DHCPv6PrefixDelegation=</varname> is enabled, then the delegated
+          prefixes are also distributed. See <varname>DHCPv6PrefixDelegation=</varname> setting and the
+          [IPv6SendRA], [IPv6Prefix], [IPv6RoutePrefix], and [DHCPv6PrefixDelegation] sections for more
           configuration options.</para></listitem>
         </varlistentry>
         <varlistentry>
+          <term><varname>DHCPv6PrefixDelegation=</varname></term>
+          <listitem><para>Takes a boolean value. When enabled, requests prefixes using a DHCPv6 client
+          configured on another link. By default, an address within each delegated prefix will be
+          assigned, and the prefixes will be announced through IPv6 Router Advertisement when
+          <varname>IPv6SendRA=</varname> is enabled. Such default settings can be configured in
+          [DHCPv6PrefixDelegation] section.</para></listitem>
+        </varlistentry>
+        <varlistentry>
           <term><varname>IPv6MTUBytes=</varname></term>
           <listitem><para>Configures IPv6 maximum transmission unit (MTU).
           An integer greater than or equal to 1280 bytes. When unset, the kernel's default will be used.
@@ -1957,9 +1963,9 @@ IPv6Token=prefixstable:2002:da8:1::</programlisting></para>
 
   <refsect1>
     <title>[DHCPv6PrefixDelegation] Section Options</title>
-    <para>The [DHCPv6PrefixDelegation] section configures delegated prefix assigned by DHCPv6 server.
-    The settings in this section are used only when <varname>IPv6PrefixDelegation=</varname> setting is
-    enabled, or set to <literal>dhcpv6</literal>.</para>
+    <para>The [DHCPv6PrefixDelegation] section configures delegated prefixes assigned by DHCPv6 server.
+    The settings in this section are used only when <varname>DHCPv6PrefixDelegation=</varname> setting
+    is enabled.</para>
 
     <variablelist class='network-directives'>
       <varlistentry>
@@ -1969,9 +1975,16 @@ IPv6Token=prefixstable:2002:da8:1::</programlisting></para>
           delegation. You can either set "auto" (the default) or a specific subnet ID (as defined in
           <ulink url="https://tools.ietf.org/html/rfc4291#section-2.5.4">RFC 4291</ulink>, section
           2.5.4), in which case the allowed value is hexadecimal, from 0 to 0x7fffffffffffffff
-          inclusive. This option is only effective when used together with
-          <varname>IPv6PrefixDelegation=</varname> and the corresponding configuration on the upstream
-          interface.</para>
+          inclusive.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>Announce=</varname></term>
+        <listitem>
+          <para>Takes a boolean. When enabled, and <varname>IPv6SendRA=</varname> in [Network] section
+          is enabled, the delegated prefixes are distributed through the IPv6 Router Advertisement.
+          Defaults to yes.</para>
         </listitem>
       </varlistentry>
 
@@ -1979,19 +1992,22 @@ IPv6Token=prefixstable:2002:da8:1::</programlisting></para>
         <term><varname>Assign=</varname></term>
         <listitem>
           <para>Takes a boolean. Specifies whether to add an address from the delegated prefixes which
-          are received from the WAN interface by the <varname>IPv6PrefixDelegation=</varname>. When
-          true (on LAN interfce), the EUI-64 algorithm will be used to form an interface identifier
-          from the delegated prefixes. Defaults to true.</para>
+          are received from the WAN interface by the DHCPv6 Prefix Delegation. When true (on LAN
+          interfce), the EUI-64 algorithm will be used by default to form an interface identifier from
+          the delegated prefixes. See also <varname>Token=</varname> setting below. Defaults to yes.
+          </para>
         </listitem>
       </varlistentry>
 
       <varlistentry>
         <term><varname>Token=</varname></term>
         <listitem>
-          <para>Specifies an optional address generation mode for <varname>Assign=</varname>. Takes an
-          IPv6 address. When set, the lower bits of the supplied address are combined with the upper
-          bits of a delegatad prefix received from the WAN interface by the
-          <varname>IPv6PrefixDelegation=</varname> prefixes to form a complete address.</para>
+          <para>Specifies an optional address generation mode for assigning an address in each
+          delegated prefix. Takes an IPv6 address. When set, the lower bits of the supplied address is
+          combined with the upper bits of each delegatad prefix received from the WAN interface by the
+          DHCPv6 Prefix Delegation to form a complete address. When <varname>Assign=</varname> is
+          disabled, this setting is ignored. When unset, the EUI-64 algorithm will be used to form
+          addresses. Defaults to unset.</para>
         </listitem>
       </varlistentry>
     </variablelist>
@@ -2213,10 +2229,11 @@ IPv6Token=prefixstable:2002:da8:1::</programlisting></para>
   </refsect1>
 
   <refsect1>
-    <title>[IPv6PrefixDelegation] Section Options</title>
-    <para>The [IPv6PrefixDelegation] section contains settings for sending IPv6 Router Advertisements and
-    whether to act as a router, if enabled via the <varname>IPv6PrefixDelegation=</varname> option described
-    above. IPv6 network prefixes are defined with one or more [IPv6Prefix] sections.</para>
+    <title>[IPv6SendRA] Section Options</title>
+    <para>The [IPv6SendRA] section contains settings for sending IPv6 Router Advertisements and whether
+    to act as a router, if enabled via the <varname>IPv6SendRA=</varname> option described above. IPv6
+    network prefixes or routes are defined with one or more [IPv6Prefix] or [IPv6RoutePrefix] sections.
+    </para>
 
     <variablelist class='network-directives'>
 
@@ -3586,10 +3603,13 @@ DHCP=ipv6</programlisting>
 Name=enp2s0
 
 [Network]
-IPv6PrefixDelegation=dhcpv6</programlisting>
+IPv6SendRA=yes
+DHCPv6PrefixDelegation=yes</programlisting>
 
-      <para>This will enable IPv6 PD on the interface enp1s0 as an upstream interface where the
-      DHCPv6 client is running and enp2s0 as a downstream interface where the prefix is delegated to.</para>
+      <para>This will enable DHCPv6-PD on the interface enp1s0 as an upstream interface where the
+      DHCPv6 client is running and enp2s0 as a downstream interface where the prefix is delegated to.
+      The delegated prefixes are distributed by IPv6 Router Advertisement on the downstream network.
+      </para>
     </example>
 
     <example>
diff --git a/src/network/networkd-address.c b/src/network/networkd-address.c
index 636812b556..9130fae778 100644
--- a/src/network/networkd-address.c
+++ b/src/network/networkd-address.c
@@ -980,6 +980,7 @@ static int static_address_configure(const Address *address, Link *link, bool upd
 
 int link_set_addresses(Link *link) {
         Address *ad;
+        Prefix *p;
         int r;
 
         assert(link);
@@ -1000,32 +1001,28 @@ int link_set_addresses(Link *link) {
                         return r;
         }
 
-        if (link->network->router_prefix_delegation & RADV_PREFIX_DELEGATION_STATIC) {
-                Prefix *p;
+        HASHMAP_FOREACH(p, link->network->prefixes_by_section) {
+                _cleanup_(address_freep) Address *address = NULL;
 
-                HASHMAP_FOREACH(p, link->network->prefixes_by_section) {
-                        _cleanup_(address_freep) Address *address = NULL;
-
-                        if (!p->assign)
-                                continue;
+                if (!p->assign)
+                        continue;
 
-                        r = address_new(&address);
-                        if (r < 0)
-                                return log_oom();
+                r = address_new(&address);
+                if (r < 0)
+                        return log_oom();
 
-                        r = sd_radv_prefix_get_prefix(p->radv_prefix, &address->in_addr.in6, &address->prefixlen);
-                        if (r < 0)
-                                return log_link_warning_errno(link, r, "Could not get RA prefix: %m");
+                r = sd_radv_prefix_get_prefix(p->radv_prefix, &address->in_addr.in6, &address->prefixlen);
+                if (r < 0)
+                        return log_link_warning_errno(link, r, "Could not get RA prefix: %m");
 
-                        r = generate_ipv6_eui_64_address(link, &address->in_addr.in6);
-                        if (r < 0)
-                                return log_link_warning_errno(link, r, "Could not generate EUI64 address: %m");
+                r = generate_ipv6_eui_64_address(link, &address->in_addr.in6);
+                if (r < 0)
+                        return log_link_warning_errno(link, r, "Could not generate EUI64 address: %m");
 
-                        address->family = AF_INET6;
-                        r = static_address_configure(address, link, true);
-                        if (r < 0)
-                                return r;
-                }
+                address->family = AF_INET6;
+                r = static_address_configure(address, link, true);
+                if (r < 0)
+                        return r;
         }
 
         if (link->address_messages == 0) {
diff --git a/src/network/networkd-dhcp4.c b/src/network/networkd-dhcp4.c
index a881df8bb4..bb8c34f7cc 100644
--- a/src/network/networkd-dhcp4.c
+++ b/src/network/networkd-dhcp4.c
@@ -1457,8 +1457,8 @@ int dhcp4_configure(Link *link) {
                         return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set max attempts: %m");
         }
 
-        if (link->network->ip_service_type > 0) {
-                r = sd_dhcp_client_set_service_type(link->dhcp_client, link->network->ip_service_type);
+        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_error_errno(link, r, "DHCP4 CLIENT: Failed to set IP service type: %m");
         }
diff --git a/src/network/networkd-dhcp6.c b/src/network/networkd-dhcp6.c
index 5217497f98..d9cc4ccf41 100644
--- a/src/network/networkd-dhcp6.c
+++ b/src/network/networkd-dhcp6.c
@@ -31,7 +31,7 @@ bool link_dhcp6_pd_is_enabled(Link *link) {
         if (!link->network)
                 return false;
 
-        return link->network->router_prefix_delegation & RADV_PREFIX_DELEGATION_DHCP6;
+        return link->network->dhcp6_pd;
 }
 
 static bool dhcp6_lease_has_pd_prefix(sd_dhcp6_lease *lease) {
@@ -421,11 +421,14 @@ static int dhcp6_pd_assign_prefix(Link *link, const union in_addr_union *prefix,
         int r;
 
         assert(link);
+        assert(link->network);
         assert(prefix);
 
-        r = radv_add_prefix(link, &prefix->in6, prefix_len, lifetime_preferred, lifetime_valid);
-        if (r < 0)
-                return r;
+        if (link->network->dhcp6_pd_announce) {
+                r = radv_add_prefix(link, &prefix->in6, prefix_len, lifetime_preferred, lifetime_valid);
+                if (r < 0)
+                        return r;
+        }
 
         r = dhcp6_set_pd_route(link, prefix, pd_prefix);
         if (r < 0)
@@ -1424,7 +1427,7 @@ int dhcp6_configure(Link *link) {
         if (r < 0)
                 return log_link_error_errno(link, r, "DHCP6 CLIENT: Failed to set ifindex: %m");
 
-        if (link->network->rapid_commit) {
+        if (link->network->dhcp6_rapid_commit) {
                 r = sd_dhcp6_client_set_request_option(client, SD_DHCP6_OPTION_RAPID_COMMIT);
                 if (r < 0)
                         return log_link_error_errno(link, r, "DHCP6 CLIENT: Failed to set request flag for rapid commit: %m");
diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf
index 21d2e820e9..5cc9e3e8f6 100644
--- a/src/network/networkd-network-gperf.gperf
+++ b/src/network/networkd-network-gperf.gperf
@@ -126,6 +126,8 @@ Network.BindCarrier,                         config_parse_strv,
 Network.ConfigureWithoutCarrier,             config_parse_bool,                                        0,                             offsetof(Network, configure_without_carrier)
 Network.IgnoreCarrierLoss,                   config_parse_tristate,                                    0,                             offsetof(Network, ignore_carrier_loss)
 Network.KeepConfiguration,                   config_parse_keep_configuration,                          0,                             offsetof(Network, keep_configuration)
+Network.IPv6SendRA,                          config_parse_router_prefix_delegation,                    0,                             offsetof(Network, router_prefix_delegation)
+Network.DHCPv6PrefixDelegation,              config_parse_tristate,                                    0,                             offsetof(Network, dhcp6_pd)
 Address.Address,                             config_parse_address,                                     0,                             0
 Address.Peer,                                config_parse_address,                                     0,                             0
 Address.Broadcast,                           config_parse_broadcast,                                   0,                             0
@@ -209,14 +211,14 @@ DHCPv4.SendRelease,                          config_parse_bool,
 DHCPv4.SendDecline,                          config_parse_bool,                                        0,                             offsetof(Network, dhcp_send_decline)
 DHCPv4.DenyList,                             config_parse_dhcp_acl_ip_address,                         0,                             0
 DHCPv4.AllowList,                            config_parse_dhcp_acl_ip_address,                         0,                             0
-DHCPv4.IPServiceType,                        config_parse_dhcp_ip_service_type,                        0,                             offsetof(Network, ip_service_type)
+DHCPv4.IPServiceType,                        config_parse_dhcp_ip_service_type,                        0,                             offsetof(Network, dhcp_ip_service_type)
 DHCPv4.SendOption,                           config_parse_dhcp_send_option,                            AF_INET,                       offsetof(Network, dhcp_client_send_options)
 DHCPv4.SendVendorOption,                     config_parse_dhcp_send_option,                            0,                             offsetof(Network, dhcp_client_send_vendor_options)
 DHCPv4.RouteMTUBytes,                        config_parse_mtu,                                         AF_INET,                       offsetof(Network, dhcp_route_mtu)
 DHCPv4.FallbackLeaseLifetimeSec,             config_parse_dhcp_fallback_lease_lifetime,                0,                             0
 DHCPv6.UseDNS,                               config_parse_dhcp_use_dns,                                0,                             0
 DHCPv6.UseNTP,                               config_parse_dhcp_use_ntp,                                0,                             0
-DHCPv6.RapidCommit,                          config_parse_bool,                                        0,                             offsetof(Network, rapid_commit)
+DHCPv6.RapidCommit,                          config_parse_bool,                                        0,                             offsetof(Network, dhcp6_rapid_commit)
 DHCPv6.MUDURL,                               config_parse_dhcp6_mud_url,                               0,                             0
 DHCPv6.RequestOptions,                       config_parse_dhcp_request_options,                        AF_INET6,                      0
 DHCPv6.UserClass,                            config_parse_dhcp_user_class,                             AF_INET6,                      offsetof(Network, dhcp6_user_class)
@@ -280,19 +282,19 @@ BridgeMDB.VLANId,                            config_parse_mdb_vlan_id,
 BridgeVLAN.PVID,                             config_parse_brvlan_pvid,                                 0,                             0
 BridgeVLAN.VLAN,                             config_parse_brvlan_vlan,                                 0,                             0
 BridgeVLAN.EgressUntagged,                   config_parse_brvlan_untagged,                             0,                             0
-Network.IPv6PrefixDelegation,                config_parse_router_prefix_delegation,                    0,                             offsetof(Network, router_prefix_delegation)
 DHCPv6PrefixDelegation.SubnetId,             config_parse_dhcp6_pd_subnet_id,                          0,                             offsetof(Network, dhcp6_pd_subnet_id)
+DHCPv6PrefixDelegation.Announce,             config_parse_bool,                                        0,                             offsetof(Network, dhcp6_pd_announce)
 DHCPv6PrefixDelegation.Assign,               config_parse_bool,                                        0,                             offsetof(Network, dhcp6_pd_assign)
 DHCPv6PrefixDelegation.Token,                config_parse_dhcp6_pd_token,                              0,                             offsetof(Network, dhcp6_pd_token)
-IPv6PrefixDelegation.RouterLifetimeSec,      config_parse_sec,                                         0,                             offsetof(Network, router_lifetime_usec)
-IPv6PrefixDelegation.Managed,                config_parse_bool,                                        0,                             offsetof(Network, router_managed)
-IPv6PrefixDelegation.OtherInformation,       config_parse_bool,                                        0,                             offsetof(Network, router_other_information)
-IPv6PrefixDelegation.RouterPreference,       config_parse_router_preference,                           0,                             0
-IPv6PrefixDelegation.EmitDNS,                config_parse_bool,                                        0,                             offsetof(Network, router_emit_dns)
-IPv6PrefixDelegation.DNS,                    config_parse_radv_dns,                                    0,                             0
-IPv6PrefixDelegation.EmitDomains,            config_parse_bool,                                        0,                             offsetof(Network, router_emit_domains)
-IPv6PrefixDelegation.Domains,                config_parse_radv_search_domains,                         0,                             0
-IPv6PrefixDelegation.DNSLifetimeSec,         config_parse_sec,                                         0,                             offsetof(Network, router_dns_lifetime_usec)
+IPv6SendRA.RouterLifetimeSec,                config_parse_sec,                                         0,                             offsetof(Network, router_lifetime_usec)
+IPv6SendRA.Managed,                          config_parse_bool,                                        0,                             offsetof(Network, router_managed)
+IPv6SendRA.OtherInformation,                 config_parse_bool,                                        0,                             offsetof(Network, router_other_information)
+IPv6SendRA.RouterPreference,                 config_parse_router_preference,                           0,                             0
+IPv6SendRA.EmitDNS,                          config_parse_bool,                                        0,                             offsetof(Network, router_emit_dns)
+IPv6SendRA.DNS,                              config_parse_radv_dns,                                    0,                             0
+IPv6SendRA.EmitDomains,                      config_parse_bool,                                        0,                             offsetof(Network, router_emit_domains)
+IPv6SendRA.Domains,                          config_parse_radv_search_domains,                         0,                             0
+IPv6SendRA.DNSLifetimeSec,                   config_parse_sec,                                         0,                             offsetof(Network, router_dns_lifetime_usec)
 IPv6Prefix.Prefix,                           config_parse_prefix,                                      0,                             0
 IPv6Prefix.OnLink,                           config_parse_prefix_flags,                                0,                             0
 IPv6Prefix.AddressAutoconfiguration,         config_parse_prefix_flags,                                0,                             0
@@ -429,6 +431,16 @@ TrivialLinkEqualizer.Handle,                 config_parse_qdisc_handle,
 TrivialLinkEqualizer.Id,                     config_parse_trivial_link_equalizer_id,                   QDISC_KIND_TEQL,               0
 /* backwards compatibility: do not add new entries to this section */
 Network.IPv4LL,                              config_parse_ipv4ll,                                      0,                             offsetof(Network, link_local)
+Network.IPv6PrefixDelegation,                config_parse_router_prefix_delegation,                    0,                             offsetof(Network, router_prefix_delegation)
+IPv6PrefixDelegation.RouterLifetimeSec,      config_parse_sec,                                         0,                             offsetof(Network, router_lifetime_usec)
+IPv6PrefixDelegation.Managed,                config_parse_bool,                                        0,                             offsetof(Network, router_managed)
+IPv6PrefixDelegation.OtherInformation,       config_parse_bool,                                        0,                             offsetof(Network, router_other_information)
+IPv6PrefixDelegation.RouterPreference,       config_parse_router_preference,                           0,                             0
+IPv6PrefixDelegation.EmitDNS,                config_parse_bool,                                        0,                             offsetof(Network, router_emit_dns)
+IPv6PrefixDelegation.DNS,                    config_parse_radv_dns,                                    0,                             0
+IPv6PrefixDelegation.EmitDomains,            config_parse_bool,                                        0,                             offsetof(Network, router_emit_domains)
+IPv6PrefixDelegation.Domains,                config_parse_radv_search_domains,                         0,                             0
+IPv6PrefixDelegation.DNSLifetimeSec,         config_parse_sec,                                         0,                             offsetof(Network, router_dns_lifetime_usec)
 DHCPv4.BlackList,                            config_parse_dhcp_acl_ip_address,                         0,                             0
 DHCP.ClientIdentifier,                       config_parse_dhcp_client_identifier,                      0,                             offsetof(Network, dhcp_client_identifier)
 DHCP.UseDNS,                                 config_parse_dhcp_use_dns,                                0,                             0
@@ -452,7 +464,7 @@ DHCP.RouteTable,                             config_parse_section_route_table,
 DHCP.UseTimezone,                            config_parse_bool,                                        0,                             offsetof(Network, dhcp_use_timezone)
 DHCP.IAID,                                   config_parse_iaid,                                        0,                             0
 DHCP.ListenPort,                             config_parse_uint16,                                      0,                             offsetof(Network, dhcp_client_port)
-DHCP.RapidCommit,                            config_parse_bool,                                        0,                             offsetof(Network, rapid_commit)
+DHCP.RapidCommit,                            config_parse_bool,                                        0,                             offsetof(Network, dhcp6_rapid_commit)
 DHCP.ForceDHCPv6PDOtherInformation,          config_parse_bool,                                        0,                             offsetof(Network, dhcp6_force_pd_other_information)
 DHCPv4.UseDomainName,                        config_parse_dhcp_use_domains,                            0,                             offsetof(Network, dhcp_use_domains)
 DHCPv4.CriticalConnection,                   config_parse_tristate,                                    0,                             offsetof(Network, dhcp_critical)
diff --git a/src/network/networkd-network.c b/src/network/networkd-network.c
index 6bfc4cb9eb..426dd0a8f0 100644
--- a/src/network/networkd-network.c
+++ b/src/network/networkd-network.c
@@ -214,14 +214,6 @@ int network_verify(Network *network) {
         if (network->link_local < 0)
                 network->link_local = network->bridge ? ADDRESS_FAMILY_NO : ADDRESS_FAMILY_IPV6;
 
-        if (!FLAGS_SET(network->link_local, ADDRESS_FAMILY_IPV6)) {
-                if (network->router_prefix_delegation != RADV_PREFIX_DELEGATION_NONE) {
-                        log_warning("%s: IPv6PrefixDelegation= is enabled but IPv6 link local addressing is disabled. "
-                                    "Disabling IPv6PrefixDelegation=.", network->filename);
-                        network->router_prefix_delegation = RADV_PREFIX_DELEGATION_NONE;
-                }
-        }
-
         if (FLAGS_SET(network->link_local, ADDRESS_FAMILY_FALLBACK_IPV4) &&
             !FLAGS_SET(network->dhcp, ADDRESS_FAMILY_IPV4)) {
                 log_warning("%s: fallback assignment of IPv4 link local address is enabled but DHCPv4 is disabled. "
@@ -235,6 +227,7 @@ int network_verify(Network *network) {
 
         network_adjust_ipv6_accept_ra(network);
         network_adjust_dhcp(network);
+        network_adjust_radv(network);
 
         if (network->mtu > 0 && network->dhcp_use_mtu) {
                 log_warning("%s: MTUBytes= in [Link] section and UseMTU= in [DHCP] section are set. "
@@ -336,7 +329,16 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
 
                 .required_for_online = true,
                 .required_operstate_for_online = LINK_OPERSTATE_RANGE_DEFAULT,
+                .arp = -1,
+                .multicast = -1,
+                .allmulticast = -1,
+
+                .configure_without_carrier = false,
+                .ignore_carrier_loss = -1,
+                .keep_configuration = _KEEP_CONFIGURATION_INVALID,
+
                 .dhcp = ADDRESS_FAMILY_NO,
+                .duid.type = _DUID_TYPE_INVALID,
                 .dhcp_critical = -1,
                 .dhcp_use_ntp = true,
                 .dhcp_use_sip = true,
@@ -358,14 +360,17 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
                 .dhcp_use_mtu = false,
                 /* NOTE: from man: UseTimezone=... Defaults to "no".*/
                 .dhcp_use_timezone = false,
-                .rapid_commit = true,
+                .dhcp_ip_service_type = -1,
 
+                .dhcp6_rapid_commit = true,
                 .dhcp6_route_metric = DHCP_ROUTE_METRIC,
                 .dhcp6_use_ntp = true,
                 .dhcp6_use_dns = true,
 
-                .dhcp6_pd_subnet_id = -1,
+                .dhcp6_pd = -1,
+                .dhcp6_pd_announce = true,
                 .dhcp6_pd_assign = true,
+                .dhcp6_pd_subnet_id = -1,
 
                 .dhcp_server_emit[SD_DHCP_LEASE_DNS].emit = true,
                 .dhcp_server_emit[SD_DHCP_LEASE_NTP].emit = true,
@@ -404,17 +409,13 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
                 .ipv6ll_address_gen_mode = _IPV6_LINK_LOCAL_ADDRESS_GEN_MODE_INVALID,
 
                 .ipv4_accept_local = -1,
-
                 .ipv6_privacy_extensions = IPV6_PRIVACY_EXTENSIONS_NO,
                 .ipv6_accept_ra = -1,
                 .ipv6_dad_transmits = -1,
                 .ipv6_hop_limit = -1,
                 .ipv6_proxy_ndp = -1,
-                .duid.type = _DUID_TYPE_INVALID,
                 .proxy_arp = -1,
-                .arp = -1,
-                .multicast = -1,
-                .allmulticast = -1,
+
                 .ipv6_accept_ra_use_dns = true,
                 .ipv6_accept_ra_use_autonomous_prefix = true,
                 .ipv6_accept_ra_use_onlink_prefix = true,
@@ -422,15 +423,11 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
                 .ipv6_accept_ra_route_table_set = false,
                 .ipv6_accept_ra_start_dhcp6_client = true,
 
-                .configure_without_carrier = false,
-                .ignore_carrier_loss = -1,
-                .keep_configuration = _KEEP_CONFIGURATION_INVALID,
                 .can_triple_sampling = -1,
                 .can_termination = -1,
                 .can_listen_only = -1,
                 .can_fd_mode = -1,
                 .can_non_iso = -1,
-                .ip_service_type = -1,
         };
 
         r = config_parse_many(
@@ -456,6 +453,7 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
                         "BridgeFDB\0"
                         "BridgeMDB\0"
                         "BridgeVLAN\0"
+                        "IPv6SendRA\0"
                         "IPv6PrefixDelegation\0"
                         "IPv6Prefix\0"
                         "IPv6RoutePrefix\0"
@@ -620,11 +618,11 @@ static Network *network_free(Network *network) {
         for (unsigned i = 0; i < network->n_dns; i++)
                 in_addr_full_free(network->dns[i]);
         free(network->dns);
-        ordered_set_free_free(network->search_domains);
-        ordered_set_free_free(network->route_domains);
+        ordered_set_free(network->search_domains);
+        ordered_set_free(network->route_domains);
         strv_free(network->bind_carrier);
 
-        ordered_set_free_free(network->router_search_domains);
+        ordered_set_free(network->router_search_domains);
         free(network->router_dns);
         set_free_free(network->ndisc_deny_listed_prefix);
 
@@ -864,8 +862,8 @@ int config_parse_domains(
         assert(rvalue);
 
         if (isempty(rvalue)) {
-                n->search_domains = ordered_set_free_free(n->search_domains);
-                n->route_domains = ordered_set_free_free(n->route_domains);
+                n->search_domains = ordered_set_free(n->search_domains);
+                n->route_domains = ordered_set_free(n->route_domains);
                 return 0;
         }
 
@@ -913,7 +911,7 @@ int config_parse_domains(
                 }
 
                 OrderedSet **set = is_route ? &n->route_domains : &n->search_domains;
-                r = ordered_set_ensure_allocated(set, &string_hash_ops);
+                r = ordered_set_ensure_allocated(set, &string_hash_ops_free);
                 if (r < 0)
                         return log_oom();
 
diff --git a/src/network/networkd-network.h b/src/network/networkd-network.h
index ccf739c851..92c7a4636f 100644
--- a/src/network/networkd-network.h
+++ b/src/network/networkd-network.h
@@ -57,12 +57,14 @@ typedef struct NetworkDHCPServerEmitAddress {
 struct Network {
         Manager *manager;
 
-        char *filename;
+        unsigned n_ref;
+
         char *name;
+        char *filename;
         usec_t timestamp;
+        char *description;
 
-        unsigned n_ref;
-
+        /* [Match] section */
         Set *match_mac;
         Set *match_permanent_mac;
         char **match_path;
@@ -75,8 +77,7 @@ struct Network {
         Set *match_bssid;
         LIST_HEAD(Condition, conditions);
 
-        char *description;
-
+        /* Master or stacked netdevs */
         NetDev *bridge;
         NetDev *bond;
         NetDev *vrf;
@@ -87,9 +88,31 @@ struct Network {
         char *vrf_name;
         Hashmap *stacked_netdev_names;
 
+        /* [Link] section */
+        struct ether_addr *mac;
+        uint32_t mtu;
+        uint32_t group;
+        int arp;
+        int multicast;
+        int allmulticast;
+        bool unmanaged;
+        bool required_for_online; /* Is this network required to be considered online? */
+        LinkOperationalStateRange required_operstate_for_online;
+
+        /* misc settings */
+        bool configure_without_carrier;
+        int ignore_carrier_loss;
+        KeepConfiguration keep_configuration;
+        char **bind_carrier;
+        bool default_route_on_device;
+        bool ip_masquerade;
+
         /* DHCP Client Support */
         AddressFamily dhcp;
         DHCPClientIdentifier dhcp_client_identifier;
+        DUID duid;
+        uint32_t iaid;
+        bool iaid_set;
         char *dhcp_vendor_class_identifier;
         char *dhcp_mudurl;
         char **dhcp_user_class;
@@ -102,7 +125,7 @@ struct Network {
         uint32_t dhcp_route_mtu;
         uint16_t dhcp_client_port;
         int dhcp_critical;
-        int ip_service_type;
+        int dhcp_ip_service_type;
         bool dhcp_anonymize;
         bool dhcp_send_hostname;
         bool dhcp_broadcast;
@@ -116,7 +139,6 @@ struct Network {
         bool dhcp_use_routes;
         int dhcp_use_gateway;
         bool dhcp_use_timezone;
-        bool rapid_commit;
         bool dhcp_use_hostname;
         bool dhcp_route_table_set;
         bool dhcp_send_release;
@@ -127,14 +149,13 @@ struct Network {
         Set *dhcp_request_options;
         OrderedHashmap *dhcp_client_send_options;
         OrderedHashmap *dhcp_client_send_vendor_options;
-        OrderedHashmap *dhcp_server_send_options;
-        OrderedHashmap *dhcp_server_send_vendor_options;
 
         /* DHCPv6 Client support*/
         bool dhcp6_use_dns;
         bool dhcp6_use_dns_set;
         bool dhcp6_use_ntp;
         bool dhcp6_use_ntp_set;
+        bool dhcp6_rapid_commit;
         uint8_t dhcp6_pd_length;
         uint32_t dhcp6_route_metric;
         bool dhcp6_route_metric_set;
@@ -146,6 +167,8 @@ struct Network {
         OrderedHashmap *dhcp6_client_send_options;
         OrderedHashmap *dhcp6_client_send_vendor_options;
         Set *dhcp6_request_options;
+        /* Start DHCPv6 PD also when 'O' RA flag is set, see RFC 7084, WPD-4 */
+        bool dhcp6_force_pd_other_information;
 
         /* DHCP Server Support */
         bool dhcp_server;
@@ -156,15 +179,15 @@ struct Network {
         usec_t dhcp_server_default_lease_time_usec, dhcp_server_max_lease_time_usec;
         uint32_t dhcp_server_pool_offset;
         uint32_t dhcp_server_pool_size;
+        OrderedHashmap *dhcp_server_send_options;
+        OrderedHashmap *dhcp_server_send_vendor_options;
 
         /* link local addressing support */
         AddressFamily link_local;
         IPv6LinkLocalAddressGenMode ipv6ll_address_gen_mode;
         bool ipv4ll_route;
 
-        bool default_route_on_device;
-
-        /* IPv6 prefix delegation support */
+        /* IPv6 RA support */
         RADVPrefixDelegation router_prefix_delegation;
         usec_t router_lifetime_usec;
         uint8_t router_preference;
@@ -176,13 +199,12 @@ struct Network {
         struct in6_addr *router_dns;
         unsigned n_router_dns;
         OrderedSet *router_search_domains;
-        bool dhcp6_force_pd_other_information; /* Start DHCPv6 PD also when 'O'
-                                                  RA flag is set, see RFC 7084,
-                                                  WPD-4 */
 
         /* DHCPv6 Prefix Delegation support */
-        int64_t dhcp6_pd_subnet_id;
+        int dhcp6_pd;
+        bool dhcp6_pd_announce;
         bool dhcp6_pd_assign;
+        int64_t dhcp6_pd_subnet_id;
         union in_addr_union dhcp6_pd_token;
 
         /* Bridge Support */
@@ -201,6 +223,7 @@ struct Network {
         uint16_t priority;
         MulticastRouter multicast_router;
 
+        /* Bridge VLAN */
         bool use_br_vlan;
         uint16_t pvid;
         uint32_t br_vid_bitmap[BRIDGE_VLAN_BITMAP_LEN];
@@ -218,18 +241,19 @@ struct Network {
         int can_fd_mode;
         int can_non_iso;
 
+        /* sysctl settings */
         AddressFamily ip_forward;
-        bool ip_masquerade;
         int ipv4_accept_local;
-
-        int ipv6_accept_ra;
         int ipv6_dad_transmits;
         int ipv6_hop_limit;
-        int ipv6_proxy_ndp;
-        Set *ipv6_proxy_ndp_addresses;
         int proxy_arp;
         uint32_t ipv6_mtu;
+        IPv6PrivacyExtensions ipv6_privacy_extensions;
+        int ipv6_proxy_ndp;
+        Set *ipv6_proxy_ndp_addresses;
 
+        /* IPv6 accept RA */
+        int ipv6_accept_ra;
         bool ipv6_accept_ra_use_dns;
         bool ipv6_accept_ra_use_autonomous_prefix;
         bool ipv6_accept_ra_use_onlink_prefix;
@@ -242,26 +266,6 @@ struct Network {
         Set *ndisc_deny_listed_prefix;
         OrderedSet *ipv6_tokens;
 
-        IPv6PrivacyExtensions ipv6_privacy_extensions;
-
-        struct ether_addr *mac;
-        uint32_t mtu;
-        uint32_t group;
-        int arp;
-        int multicast;
-        int allmulticast;
-        bool unmanaged;
-        bool configure_without_carrier;
-        int ignore_carrier_loss;
-        KeepConfiguration keep_configuration;
-        uint32_t iaid;
-        DUID duid;
-
-        bool iaid_set;
-
-        bool required_for_online; /* Is this network required to be considered online? */
-        LinkOperationalStateRange required_operstate_for_online;
-
         /* LLDP support */
         LLDPMode lldp_mode; /* LLDP reception */
         LLDPEmit lldp_emit; /* LLDP transmission */
@@ -284,7 +288,6 @@ struct Network {
         struct in_addr_full **dns;
         unsigned n_dns;
         OrderedSet *search_domains, *route_domains;
-
         int dns_default_route;
         ResolveSupport llmnr;
         ResolveSupport mdns;
@@ -292,8 +295,8 @@ struct Network {
         DnsOverTlsMode dns_over_tls_mode;
         Set *dnssec_negative_trust_anchors;
 
+        /* NTP */
         char **ntp;
-        char **bind_carrier;
 };
 
 Network *network_ref(Network *network);
diff --git a/src/network/networkd-radv.c b/src/network/networkd-radv.c
index bb80e91b6c..eb10f21cbd 100644
--- a/src/network/networkd-radv.c
+++ b/src/network/networkd-radv.c
@@ -180,6 +180,35 @@ void network_drop_invalid_route_prefixes(Network *network) {
                         route_prefix_free(prefix);
 }
 
+void network_adjust_radv(Network *network) {
+        assert(network);
+
+        /* After this function is called, network->router_prefix_delegation can be treated as a boolean. */
+
+        if (network->dhcp6_pd < 0)
+                /* For backward compatibility. */
+                network->dhcp6_pd = FLAGS_SET(network->router_prefix_delegation, RADV_PREFIX_DELEGATION_DHCP6);
+
+        if (!FLAGS_SET(network->link_local, ADDRESS_FAMILY_IPV6)) {
+                if (network->router_prefix_delegation != RADV_PREFIX_DELEGATION_NONE)
+                        log_warning("%s: IPv6PrefixDelegation= is enabled but IPv6 link local addressing is disabled. "
+                                    "Disabling IPv6PrefixDelegation=.", network->filename);
+
+                network->router_prefix_delegation = RADV_PREFIX_DELEGATION_NONE;
+        }
+
+        if (network->router_prefix_delegation == RADV_PREFIX_DELEGATION_NONE) {
+                network->n_router_dns = 0;
+                network->router_dns = mfree(network->router_dns);
+                network->router_search_domains = ordered_set_free(network->router_search_domains);
+        }
+
+        if (!FLAGS_SET(network->router_prefix_delegation, RADV_PREFIX_DELEGATION_STATIC)) {
+                network->prefixes_by_section = hashmap_free_with_destructor(network->prefixes_by_section, prefix_free);
+                network->route_prefixes_by_section = hashmap_free_with_destructor(network->route_prefixes_by_section, route_prefix_free);
+        }
+}
+
 int config_parse_prefix(
                 const char *unit,
                 const char *filename,
@@ -608,10 +637,12 @@ static bool link_radv_enabled(Link *link) {
         if (!link_ipv6ll_enabled(link))
                 return false;
 
-        return link->network->router_prefix_delegation != RADV_PREFIX_DELEGATION_NONE;
+        return link->network->router_prefix_delegation;
 }
 
 int radv_configure(Link *link) {
+        RoutePrefix *q;
+        Prefix *p;
         int r;
 
         assert(link);
@@ -658,29 +689,24 @@ int radv_configure(Link *link) {
                         return r;
         }
 
-        if (link->network->router_prefix_delegation & RADV_PREFIX_DELEGATION_STATIC) {
-                RoutePrefix *q;
-                Prefix *p;
-
-                HASHMAP_FOREACH(p, link->network->prefixes_by_section) {
-                        r = sd_radv_add_prefix(link->radv, p->radv_prefix, false);
-                        if (r == -EEXIST)
-                                continue;
-                        if (r == -ENOEXEC) {
-                                log_link_warning_errno(link, r, "[IPv6Prefix] section configured without Prefix= setting, ignoring section.");
-                                continue;
-                        }
-                        if (r < 0)
-                                return r;
+        HASHMAP_FOREACH(p, link->network->prefixes_by_section) {
+                r = sd_radv_add_prefix(link->radv, p->radv_prefix, false);
+                if (r == -EEXIST)
+                        continue;
+                if (r == -ENOEXEC) {
+                        log_link_warning_errno(link, r, "[IPv6Prefix] section configured without Prefix= setting, ignoring section.");
+                        continue;
                 }
+                if (r < 0)
+                        return r;
+        }
 
-                HASHMAP_FOREACH(q, link->network->route_prefixes_by_section) {
-                        r = sd_radv_add_route_prefix(link->radv, q->radv_route_prefix, false);
-                        if (r == -EEXIST)
-                                continue;
-                        if (r < 0)
-                                return r;
-                }
+        HASHMAP_FOREACH(q, link->network->route_prefixes_by_section) {
+                r = sd_radv_add_route_prefix(link->radv, q->radv_route_prefix, false);
+                if (r == -EEXIST)
+                        continue;
+                if (r < 0)
+                        return r;
         }
 
         return 0;
@@ -771,6 +797,12 @@ int config_parse_radv_dns(
         assert(lvalue);
         assert(rvalue);
 
+        if (isempty(rvalue)) {
+                n->n_router_dns = 0;
+                n->router_dns = mfree(n->router_dns);
+                return 0;
+        }
+
         for (const char *p = rvalue;;) {
                 _cleanup_free_ char *w = NULL;
                 union in_addr_union a;
@@ -832,6 +864,11 @@ int config_parse_radv_search_domains(
         assert(lvalue);
         assert(rvalue);
 
+        if (isempty(rvalue)) {
+                n->router_search_domains = ordered_set_free(n->router_search_domains);
+                return 0;
+        }
+
         for (const char *p = rvalue;;) {
                 _cleanup_free_ char *w = NULL, *idna = NULL;
 
@@ -855,7 +892,7 @@ int config_parse_radv_search_domains(
                         /* transfer ownership to simplify subsequent operations */
                         idna = TAKE_PTR(w);
 
-                r = ordered_set_ensure_allocated(&n->router_search_domains, &string_hash_ops);
+                r = ordered_set_ensure_allocated(&n->router_search_domains, &string_hash_ops_free);
                 if (r < 0)
                         return log_oom();
 
@@ -877,11 +914,51 @@ DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(
                 RADVPrefixDelegation,
                 RADV_PREFIX_DELEGATION_BOTH);
 
-DEFINE_CONFIG_PARSE_ENUM(
-                config_parse_router_prefix_delegation,
-                radv_prefix_delegation,
-                RADVPrefixDelegation,
-                "Invalid router prefix delegation");
+int config_parse_router_prefix_delegation(
+                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) {
+
+        RADVPrefixDelegation val, *ra = data;
+        int r;
+
+        assert(filename);
+        assert(lvalue);
+        assert(rvalue);
+        assert(data);
+
+        if (streq(lvalue, "IPv6SendRA")) {
+                r = parse_boolean(rvalue);
+                if (r < 0) {
+                        log_syntax(unit, LOG_WARNING, filename, line, r,
+                                   "Invalid %s= setting, ignoring assignment: %s", lvalue, rvalue);
+                        return 0;
+                }
+
+                /* When IPv6SendRA= is enabled, only static prefixes are sent by default, and users
+                 * need to explicitly enable DHCPv6PrefixDelegation=. */
+                *ra = r ? RADV_PREFIX_DELEGATION_STATIC : RADV_PREFIX_DELEGATION_NONE;
+                return 0;
+        }
+
+        /* For backward compatibility */
+        val = radv_prefix_delegation_from_string(rvalue);
+        if (val < 0) {
+                log_syntax(unit, LOG_WARNING, filename, line, 0,
+                           "Invalid %s= setting, ignoring assignment: %s", lvalue, rvalue);
+                return 0;
+        }
+
+        *ra = val;
+        return 0;
+}
 
 int config_parse_router_preference(
                 const char *unit,
diff --git a/src/network/networkd-radv.h b/src/network/networkd-radv.h
index fbb93a9acc..75c606d15e 100644
--- a/src/network/networkd-radv.h
+++ b/src/network/networkd-radv.h
@@ -47,6 +47,7 @@ RoutePrefix *route_prefix_free(RoutePrefix *prefix);
 
 void network_drop_invalid_prefixes(Network *network);
 void network_drop_invalid_route_prefixes(Network *network);
+void network_adjust_radv(Network *network);
 
 int radv_emit_dns(Link *link);
 int radv_configure(Link *link);
diff --git a/test/fuzz/fuzz-network-parser/directives.network b/test/fuzz/fuzz-network-parser/directives.network
index 1494daa0c1..cb0c3205a0 100644
--- a/test/fuzz/fuzz-network-parser/directives.network
+++ b/test/fuzz/fuzz-network-parser/directives.network
@@ -137,6 +137,7 @@ SendVendorOption=
 RouteMetric=
 [DHCPv6PrefixDelegation]
 SubnetId=
+Announce=
 Assign=
 Token=
 [Route]
@@ -190,6 +191,7 @@ DNSOverTLS=
 Bond=
 IPv6ProxyNDP=
 DNS=
+DNSDefaultRoute=
 ActiveSlave=
 LLMNR=
 DNSSEC=
@@ -207,6 +209,7 @@ ConfigureWithoutCarrier=
 NTP=
 DHCP=
 Domains=
+IPv6SendRA=
 IPv6PrefixDelegation=
 VLAN=
 DHCPServer=
@@ -214,6 +217,7 @@ BindCarrier=
 VRF=
 IgnoreCarrierLoss=
 KeepConfiguration=
+DHCPv6PrefixDelegation=
 [IPv6Prefix]
 Prefix=
 OnLink=
@@ -270,11 +274,20 @@ InvertRule=
 Family=
 SuppressPrefixLength=
 User=
+[IPv6SendRA]
+RouterPreference=
+DNSLifetimeSec=
+DNS=
+RouterLifetimeSec=
+Domains=
+EmitDNS=
+EmitDomains=
+Managed=
+OtherInformation=
 [IPv6PrefixDelegation]
 RouterPreference=
 DNSLifetimeSec=
 DNS=
-DNSDefaultRoute=
 RouterLifetimeSec=
 Domains=
 EmitDNS=
diff --git a/test/test-network/conf/ipv6-prefix.network b/test/test-network/conf/ipv6-prefix.network
index 9de0e3147b..aec1d1b2c3 100644
--- a/test/test-network/conf/ipv6-prefix.network
+++ b/test/test-network/conf/ipv6-prefix.network
@@ -2,9 +2,9 @@
 Name=veth-peer
 
 [Network]
-IPv6PrefixDelegation=yes
+IPv6SendRA=yes
 
-[IPv6PrefixDelegation]
+[IPv6SendRA]
 DNS=_link_local 2002:da8:1:0::1
 DNSLifetimeSec=1min
 
diff --git a/test/test-network/conf/ipv6ra-prefix.network b/test/test-network/conf/ipv6ra-prefix.network
index 9dc32cb4da..a0ac1e4537 100644
--- a/test/test-network/conf/ipv6ra-prefix.network
+++ b/test/test-network/conf/ipv6ra-prefix.network
@@ -3,7 +3,7 @@ Name=veth99
 
 [Network]
 DHCP=no
-IPv6PrefixDelegation=yes
+IPv6SendRA=yes
 
 [IPv6Prefix]
 Prefix=2001:db8:0:1::/64