Merge pull request #23292 from alexhenrie/dhcpv6

network: clarify relationship between RA flags and DHCPv6 modes

man/systemd.network.xml

@@ -328,9 +328,10 @@
           <literal>no</literal>.</para>
 
           <para>Note that DHCPv6 will by default be triggered by Router Advertisement, if that is
-          enabled, regardless of this parameter. By enabling DHCPv6 support explicitly, the DHCPv6
-          client will be started regardless of the presence of routers on the link, or what flags the
-          routers pass. See <literal>IPv6AcceptRA=</literal>.</para>
+          enabled, regardless of this parameter. By explicitly enabling DHCPv6 support here, the
+          DHCPv6 client will be started in the mode specified by the <variable>WithoutRA=</variable>
+          setting in the [DHCPv6] section, regardless of the presence of routers on the link, or
+          what flags the routers pass. See <literal>IPv6AcceptRA=</literal>.</para>
 
           <para>Furthermore, note that by default the domain name specified through DHCP is not used
           for name resolution. See option <option>UseDomains=</option> below.</para>
@@ -2172,9 +2173,10 @@ Table=1234</programlisting></para>
       <varlistentry>
         <term><varname>WithoutRA=</varname></term>
         <listitem>
-          <para>Allows DHCPv6 client to start without router advertisements's managed or other
-          address configuration flag. Takes one of <literal>no</literal>, <literal>solicit</literal>
-          or <literal>information-request</literal>. If this is not specified,
+          <para>Allows DHCPv6 client to start without router advertisements's
+          <literal>managed</literal> or <literal>other configuration</literal> flag. Takes one of
+          <literal>no</literal>, <literal>solicit</literal>, or
+          <literal>information-request</literal>. If this is not specified,
           <literal>solicit</literal> is used when <varname>DHCPPrefixDelegation=</varname> is enabled
           and <varname>UplinkInterface=:self</varname> is specified in the [DHCPPrefixDelegation]
           section. Otherwise, defaults to <literal>no</literal>, and the DHCPv6 client will be started
@@ -2507,10 +2509,14 @@ Token=prefixstable:2002:da8:1::</programlisting></para>
         <term><varname>DHCPv6Client=</varname></term>
         <listitem>
           <para>Takes a boolean, or the special value <literal>always</literal>. When true, the
-          DHCPv6 client will be started when the RA has the managed or other information flag. If set
-          to <literal>always</literal>, the DHCPv6 client will be started in managed mode when an RA
-          is received, even if neither managed nor other information flag is set in the RA. This will
-          be ignored when <varname>WithoutRA=</varname> in the [DHCPv6] section is enabled, or
+          DHCPv6 client will be started in <literal>solicit</literal> mode if the RA has the
+          <literal>managed</literal> flag or <literal>information-request</literal> mode if the RA
+          lacks the <literal>managed</literal> flag but has the
+          <literal>other configuration</literal> flag. If set to <literal>always</literal>, the
+          DHCPv6 client will be started in <literal>solicit</literal> mode when an RA is received,
+          even if neither the <literal>managed</literal> nor the
+          <literal>other configuration</literal> flag is set in the RA. This will be ignored when
+          <varname>WithoutRA=</varname> in the [DHCPv6] section is enabled, or
           <varname>UplinkInterface=:self</varname> in the [DHCPPrefixDelegation] section is
           specified. Defaults to true.</para>
         </listitem>

src/libsystemd-network/sd-dhcp6-client.c

@@ -1384,7 +1384,7 @@ int sd_dhcp6_client_start(sd_dhcp6_client *client) {
         }
 
         log_dhcp6_client(client, "Starting in %s mode",
-                         client->information_request ? "Information request" : "Managed");
+                         client->information_request ? "Information request" : "Solicit");
 
         return client_start_transaction(client, state);
 }

src/network/networkd-dhcp6.c

@@ -35,7 +35,7 @@ static DHCP6ClientStartMode link_get_dhcp6_client_start_mode(Link *link) {
         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 managed 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;
 
@@ -686,7 +686,7 @@ static int dhcp6_configure(Link *link) {
                 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 managed mode. */
+        /* 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",

src/network/networkd-ndisc.c

@@ -949,13 +949,13 @@ static int ndisc_start_dhcp6_client(Link *link, sd_ndisc_router *rt) {
                         return 0;
 
                 /* (re)start DHCPv6 client in stateful or stateless mode according to RA flags.
-                 * Note, if both managed and other information bits are set, then ignore other
-                 * information bit. See RFC 4861. */
+                 * 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 managed mode
+                /* 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;

src/shared/json.h

@@ -331,9 +331,9 @@ typedef enum JsonDispatchFlags {
         JSON_SAFE       = 1 << 3, /* Don't accept "unsafe" strings in json_dispatch_string() + json_dispatch_string() */
         JSON_RELAX      = 1 << 4, /* Use relaxed user name checking in json_dispatch_user_group_name */
 
-        /* The following two may be passed into log_json() in addition to the three above */
-        JSON_DEBUG      = 1 << 4, /* Indicates that this log message is a debug message */
-        JSON_WARNING    = 1 << 5, /* Indicates that this log message is a warning message */
+        /* The following two may be passed into log_json() in addition to those above */
+        JSON_DEBUG      = 1 << 5, /* Indicates that this log message is a debug message */
+        JSON_WARNING    = 1 << 6, /* Indicates that this log message is a warning message */
 } JsonDispatchFlags;
 
 typedef int (*JsonDispatchCallback)(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);