network: add support to configure proxy ARP/WIFI

man/systemd.network.xml

@@ -1908,6 +1908,17 @@
             When unset, the kernel's default will be used.</para>
           </listitem>
         </varlistentry>
+        <varlistentry>
+          <term><varname>MulticastRouter=</varname></term>
+          <listitem>
+            <para>Configures this port for having multicast routers attached. A port with a multicast
+            router will receive all multicast traffic. Takes one of <literal>no</literal>
+            to disable multicast routers on this port, <literal>query</literal> to let the system detect
+            the presence of routers, <literal>permanent</literal> to permanently enable multicast traffic
+            forwarding on this port, or <literal>temporary</literal> to enable multicast routers temporarily
+            on this port, not depending on incoming queries. When unset, the kernel's default will be used.</para>
+          </listitem>
+        </varlistentry>
         <varlistentry>
           <term><varname>Cost=</varname></term>
           <listitem>

src/network/networkd-link.c

@@ -1648,6 +1648,12 @@ static int link_set_bridge(Link *link) {
                         return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_PRIORITY attribute: %m");
         }
 
+        if (link->network->multicast_router != _MULTICAST_ROUTER_INVALID) {
+                r = sd_netlink_message_append_u8(req, IFLA_BRPORT_MULTICAST_ROUTER, link->network->multicast_router);
+                if (r < 0)
+                        return log_link_error_errno(link, r, "Could not append IFLA_BRPORT_MULTICAST_ROUTER attribute: %m");
+        }
+
         r = sd_netlink_message_close_container(req);
         if (r < 0)
                 return log_link_error_errno(link, r, "Could not append IFLA_LINKINFO attribute: %m");

src/network/networkd-network-gperf.gperf

@@ -180,6 +180,7 @@ Bridge.Learning,                        config_parse_tristate,
 Bridge.ProxyARP,                        config_parse_tristate,                           0,                             offsetof(Network, bridge_proxy_arp)
 Bridge.ProxyARPWiFi,                    config_parse_tristate,                           0,                             offsetof(Network, bridge_proxy_arp_wifi)
 Bridge.Priority,                        config_parse_bridge_port_priority,               0,                             offsetof(Network, priority)
+Bridge.MulticastRouter,                 config_parse_multicast_router,                   0,                             offsetof(Network, multicast_router)
 BridgeFDB.MACAddress,                   config_parse_fdb_hwaddr,                         0,                             0
 BridgeFDB.VLANId,                       config_parse_fdb_vlan_id,                        0,                             0
 BridgeFDB.Destination,                  config_parse_fdb_destination,                    0,                             0

src/network/networkd-network.c

@@ -391,6 +391,7 @@ int network_load_one(Manager *manager, const char *filename) {
                 .bridge_proxy_arp = -1,
                 .bridge_proxy_arp_wifi = -1,
                 .priority = LINK_BRIDGE_PORT_PRIORITY_INVALID,
+                .multicast_router = _MULTICAST_ROUTER_INVALID,
 
                 .lldp_mode = LLDP_MODE_ROUTERS_ONLY,
 
@@ -1723,3 +1724,14 @@ int config_parse_required_for_online(
 
         return 0;
 }
+
+static const char* const multicast_router_table[_MULTICAST_ROUTER_MAX] = {
+        [MULTICAST_ROUTER_NONE] = "no",
+        [MULTICAST_ROUTER_TEMPORARY_QUERY] = "query",
+        [MULTICAST_ROUTER_PERMANENT] = "permanent",
+        [MULTICAST_ROUTER_TEMPORARY] = "temporary",
+};
+
+DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(multicast_router, MulticastRouter, _MULTICAST_ROUTER_INVALID);
+DEFINE_CONFIG_PARSE_ENUM(config_parse_multicast_router, multicast_router, MulticastRouter,
+                         "Failed to parse bridge multicast router setting");

src/network/networkd-network.h

@@ -1,6 +1,9 @@
 /* SPDX-License-Identifier: LGPL-2.1+ */
 #pragma once
 
+#include <netinet/in.h>
+#include <linux/if_bridge.h>
+
 #include "sd-bus.h"
 #include "sd-device.h"
 
@@ -84,6 +87,15 @@ typedef enum RADVPrefixDelegation {
         _RADV_PREFIX_DELEGATION_INVALID = -1,
 } RADVPrefixDelegation;
 
+typedef enum MulticastRouter {
+        MULTICAST_ROUTER_NONE            = MDB_RTR_TYPE_DISABLED,
+        MULTICAST_ROUTER_TEMPORARY_QUERY = MDB_RTR_TYPE_TEMP_QUERY,
+        MULTICAST_ROUTER_PERMANENT       = MDB_RTR_TYPE_PERM,
+        MULTICAST_ROUTER_TEMPORARY       = MDB_RTR_TYPE_TEMP,
+        _MULTICAST_ROUTER_MAX,
+        _MULTICAST_ROUTER_INVALID = -1,
+} MulticastRouter;
+
 typedef struct Manager Manager;
 
 struct Network {
@@ -185,6 +197,7 @@ struct Network {
         int bridge_proxy_arp_wifi;
         uint32_t cost;
         uint16_t priority;
+        MulticastRouter multicast_router;
 
         bool use_br_vlan;
         uint16_t pvid;
@@ -319,6 +332,7 @@ CONFIG_PARSER_PROTOTYPE(config_parse_ntp);
 CONFIG_PARSER_PROTOTYPE(config_parse_iaid);
 CONFIG_PARSER_PROTOTYPE(config_parse_required_for_online);
 CONFIG_PARSER_PROTOTYPE(config_parse_dhcp_max_attempts);
+CONFIG_PARSER_PROTOTYPE(config_parse_multicast_router);
 /* Legacy IPv4LL support */
 CONFIG_PARSER_PROTOTYPE(config_parse_ipv4ll);
 
@@ -340,3 +354,6 @@ LLDPMode lldp_mode_from_string(const char *s) _pure_;
 
 const char* radv_prefix_delegation_to_string(RADVPrefixDelegation i) _const_;
 RADVPrefixDelegation radv_prefix_delegation_from_string(const char *s) _pure_;
+
+const char* multicast_router_to_string(MulticastRouter i) _const_;
+MulticastRouter multicast_router_from_string(const char *s) _pure_;

test/fuzz/fuzz-network-parser/directives.network

@@ -12,6 +12,7 @@ NeighborSuppression=
 Learning=
 ProxyARP=
 ProxyARPWiFi=
+MulticastRouter=
 [Match]
 KernelVersion=
 Type=