network: dhcp6: re-introduce RapidCommit= setting

Previous implementation of disabling rapid commit was broken, and
dropped by 308d01f3c4decf3240ca0c6c7f91049953df7299.

Let's re-introduce the option in the correct way, as some servers seem
to return borked message when the solicit message contain the rapid
commit option.

Closes #24065.

diff --git a/man/systemd.network.xml b/man/systemd.network.xml
index 2d3bb66e39555785f631ecfee611d271917a3767..76a924cec73d2dc1facf55c037179d9955f29a5f 100644 (file)
--- a/man/systemd.network.xml
+++ b/man/systemd.network.xml
@@ -2147,6 +2147,19 @@ Table=1234</programlisting></para>
         </listitem>
       </varlistentry>
 
+      <varlistentry>
+        <term><varname>RapidCommit=</varname></term>
+        <listitem>
+          <para>Takes a boolean. The DHCPv6 client can obtain configuration parameters from a DHCPv6 server
+          through a rapid two-message exchange (solicit and reply). When the rapid commit option is set by
+          both the DHCPv6 client and the DHCPv6 server, the two-message exchange is used. Otherwise, the
+          four-message exchange (solicit, advertise, request, and reply) is used. The two-message exchange
+          provides faster client configuration. See
+          <ulink url="https://tools.ietf.org/html/rfc3315#section-17.2.1">RFC 3315</ulink> for details.
+          Defaults to true, and the two-message exchange will be used if the server support it.</para>
+        </listitem>
+      </varlistentry>
+
       <!-- How to use the DHCP lease -->
 
       <varlistentry>

diff --git a/src/network/networkd-dhcp6.c b/src/network/networkd-dhcp6.c
index d6f2c2cca3460c58c554aaddbba781ab7dc4f35c..7f9f4e12b99cff8494c624a75a92be94ccfdeb4d 100644 (file)
--- a/src/network/networkd-dhcp6.c
+++ b/src/network/networkd-dhcp6.c
@@ -695,6 +695,12 @@ static int dhcp6_configure(Link *link) {
                         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));
+
         link->dhcp6_client = TAKE_PTR(client);
 
         return 0;

diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf
index 13d521e37a2910f8c4f7e4681b87f9a3db5adab2..a4f038681a42e04217e05436f3e3281af717eaf1 100644 (file)
--- a/src/network/networkd-network-gperf.gperf
+++ b/src/network/networkd-network-gperf.gperf
@@ -262,6 +262,7 @@ DHCPv6.SendOption,                           config_parse_dhcp_send_option,
 DHCPv6.IAID,                                 config_parse_iaid,                                        AF_INET6,                      0
 DHCPv6.DUIDType,                             config_parse_duid_type,                                   0,                             offsetof(Network, dhcp6_duid)
 DHCPv6.DUIDRawData,                          config_parse_duid_rawdata,                                0,                             offsetof(Network, dhcp6_duid)
+DHCPv6.RapidCommit,                          config_parse_bool,                                        0,                             offsetof(Network, dhcp6_use_rapid_commit)
 IPv6AcceptRA.UseGateway,                     config_parse_bool,                                        0,                             offsetof(Network, ipv6_accept_ra_use_gateway)
 IPv6AcceptRA.UseRoutePrefix,                 config_parse_bool,                                        0,                             offsetof(Network, ipv6_accept_ra_use_route_prefix)
 IPv6AcceptRA.UseAutonomousPrefix,            config_parse_bool,                                        0,                             offsetof(Network, ipv6_accept_ra_use_autonomous_prefix)
@@ -555,12 +556,11 @@ DHCP.RouteMetric,                            config_parse_dhcp_or_ra_route_metri
 DHCP.RouteTable,                             config_parse_dhcp_or_ra_route_table,                      AF_INET,                       0
 DHCP.UseTimezone,                            config_parse_bool,                                        0,                             offsetof(Network, dhcp_use_timezone)
 DHCP.ListenPort,                             config_parse_uint16,                                      0,                             offsetof(Network, dhcp_client_port)
-DHCP.RapidCommit,                            config_parse_warn_compat,                                 DISABLED_LEGACY,               0
+DHCP.RapidCommit,                            config_parse_bool,                                        0,                             offsetof(Network, dhcp6_use_rapid_commit)
 DHCP.ForceDHCPv6PDOtherInformation,          config_parse_warn_compat,                                 DISABLED_LEGACY,               0
 DHCPv4.UseDomainName,                        config_parse_dhcp_use_domains,                            AF_INET,                       0
 DHCPv4.CriticalConnection,                   config_parse_tristate,                                    0,                             offsetof(Network, dhcp_critical)
 DHCPv6.RouteMetric,                          config_parse_dhcp_or_ra_route_metric,                     AF_INET6,                      0
-DHCPv6.RapidCommit,                          config_parse_warn_compat,                                 DISABLED_LEGACY,               0
 DHCPv6.ForceDHCPv6PDOtherInformation,        config_parse_warn_compat,                                 DISABLED_LEGACY,               0
 DHCPv6PrefixDelegation.SubnetId,             config_parse_dhcp_pd_subnet_id,                           0,                             offsetof(Network, dhcp_pd_subnet_id)
 DHCPv6PrefixDelegation.Announce,             config_parse_bool,                                        0,                             offsetof(Network, dhcp_pd_announce)

diff --git a/src/network/networkd-network.c b/src/network/networkd-network.c
index e090a78023e9f51995fd0f8b8ca99380ce561073..4faa43b3279eddec6f86f20b8caaf09f5eb006f0 100644 (file)
--- a/src/network/networkd-network.c
+++ b/src/network/networkd-network.c
@@ -414,6 +414,7 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
                 .dhcp6_use_dns = true,
                 .dhcp6_use_hostname = true,
                 .dhcp6_use_ntp = true,
+                .dhcp6_use_rapid_commit = true,
                 .dhcp6_duid.type = _DUID_TYPE_INVALID,
                 .dhcp6_client_start_mode = _DHCP6_CLIENT_START_MODE_INVALID,
 

diff --git a/src/network/networkd-network.h b/src/network/networkd-network.h
index c653124a9c6ec66fad171ffb4306f8c94031416d..3df7eee555e3b71e210ed38a5d3627f90edde2df 100644 (file)
--- a/src/network/networkd-network.h
+++ b/src/network/networkd-network.h
@@ -164,6 +164,7 @@ struct Network {
         bool dhcp6_use_hostname;
         bool dhcp6_use_ntp;
         bool dhcp6_use_ntp_set;
+        bool dhcp6_use_rapid_commit;
         DHCPUseDomains dhcp6_use_domains;
         bool dhcp6_use_domains_set;
         uint32_t dhcp6_iaid;