diff --git a/NEWS b/NEWS
index 54d2624951..9ffc8ba23b 100644
--- a/NEWS
+++ b/NEWS
@@ -2222,6 +2222,10 @@ CHANGES WITH 255:
specific devices explicitly. NetworkManager will soon implement a
similar logic.
+ * .network files gained a new MulticastIGMPVersion= setting in the
+ [Network] section, to control sysctl's
+ /proc/sys/net/ipv4/conf/INTERFACE/force_igmp_version setting.
+
systemctl:
* systemctl is-failed now checks the system state if no unit is
diff --git a/man/systemd.network.xml b/man/systemd.network.xml
index 6523c944ef..5090d3fb63 100644
--- a/man/systemd.network.xml
+++ b/man/systemd.network.xml
@@ -1004,6 +1004,27 @@ DuplicateAddressDetection=none
+
+ MulticastIGMPVersion=
+
+ Configures IPv4 Multicast IGMP Version to be used, and controls the value of
+ /proc/sys/net/ipv4/conf/INTERFACE/force_igmp_version.
+ Takes one of no,
+ v1, v2, or v3.
+ When no, no enforcement of an IGMP version will be applied, IGMPv1/v2 fallback are allowed, will back to
+ IGMPv3 mode again if all IGMPv1/v2 Querier Present timer expire.
+ When v1, use of IGMP version 1 will be enforced, and IGMPv1 report will be replied even if IGMPv2/v3
+ queries are received.
+ When v2, use of IGMP version 2 will be enforced, and IGMPv2 report will be replied if an IGMPv2/v3 query
+ is received, but fallback to IGMPv1 if an IGMPv1 query is received.
+ When v3, use of IGMP version 3 will be enforced, and the same reaction will be done as no.
+ Defaults to unset, and the sysctl value will be unchanged.
+
+
+
+
+
+
IPv4AcceptLocal=
diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf
index 50be74e55f..ab7f2553ec 100644
--- a/src/network/networkd-network-gperf.gperf
+++ b/src/network/networkd-network-gperf.gperf
@@ -150,6 +150,7 @@ Network.IPv4ProxyARPPrivateVLAN, config_parse_tristate,
Network.ProxyARP, config_parse_tristate, 0, offsetof(Network, proxy_arp)
Network.IPv6ProxyNDPAddress, config_parse_ipv6_proxy_ndp_address, 0, 0
Network.IPv4ReversePathFilter, config_parse_ip_reverse_path_filter, 0, offsetof(Network, ipv4_rp_filter)
+Network.MulticastIGMPVersion, config_parse_ipv4_force_igmp_version, 0, offsetof(Network, ipv4_force_igmp_version)
Network.BindCarrier, config_parse_strv, 0, offsetof(Network, bind_carrier)
Network.ConfigureWithoutCarrier, config_parse_bool, 0, offsetof(Network, configure_without_carrier)
Network.IgnoreCarrierLoss, config_parse_ignore_carrier_loss, 0, 0
diff --git a/src/network/networkd-network.c b/src/network/networkd-network.c
index 97bfe65394..2488530829 100644
--- a/src/network/networkd-network.c
+++ b/src/network/networkd-network.c
@@ -481,6 +481,7 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
.proxy_arp = -1,
.proxy_arp_pvlan = -1,
.ipv4_rp_filter = _IP_REVERSE_PATH_FILTER_INVALID,
+ .ipv4_force_igmp_version = _IPV4_FORCE_IGMP_VERSION_INVALID,
.ndisc = -1,
.ndisc_use_redirect = true,
diff --git a/src/network/networkd-network.h b/src/network/networkd-network.h
index 30ea9ac352..3ea94e0e49 100644
--- a/src/network/networkd-network.h
+++ b/src/network/networkd-network.h
@@ -340,6 +340,7 @@ struct Network {
uint32_t ipv6_mtu;
IPv6PrivacyExtensions ipv6_privacy_extensions;
IPReversePathFilter ipv4_rp_filter;
+ IPv4ForceIgmpVersion ipv4_force_igmp_version;
int ipv6_proxy_ndp;
Set *ipv6_proxy_ndp_addresses;
diff --git a/src/network/networkd-sysctl.c b/src/network/networkd-sysctl.c
index 17a2c6da38..10a35bc44b 100644
--- a/src/network/networkd-sysctl.c
+++ b/src/network/networkd-sysctl.c
@@ -408,6 +408,18 @@ static int link_set_ipv4_rp_filter(Link *link) {
return sysctl_write_ip_property_int(AF_INET, link->ifname, "rp_filter", link->network->ipv4_rp_filter, manager_get_sysctl_shadow(link->manager));
}
+static int link_set_ipv4_force_igmp_version(Link *link) {
+ assert(link);
+
+ if (!link_is_configured_for_family(link, AF_INET))
+ return 0;
+
+ if (link->network->ipv4_force_igmp_version < 0)
+ return 0;
+
+ return sysctl_write_ip_property_int(AF_INET, link->ifname, "force_igmp_version", link->network->ipv4_force_igmp_version, manager_get_sysctl_shadow(link->manager));
+}
+
static int link_set_ipv6_privacy_extensions(Link *link) {
IPv6PrivacyExtensions val;
@@ -723,6 +735,10 @@ int link_set_sysctl(Link *link) {
if (r < 0)
log_link_warning_errno(link, r, "Cannot set IPv4 reverse path filtering for interface, ignoring: %m");
+ r = link_set_ipv4_force_igmp_version(link);
+ if (r < 0)
+ log_link_warning_errno(link, r, "Cannot set IPv4 force igmp version, ignoring: %m");
+
r = link_set_ipv4_promote_secondaries(link);
if (r < 0)
log_link_warning_errno(link, r, "Cannot enable promote_secondaries for interface, ignoring: %m");
@@ -770,3 +786,13 @@ int config_parse_ip_forward_deprecated(
"and the same settings in .network files for per-interface setting.");
return 0;
}
+
+static const char* const ipv4_force_igmp_version_table[_IPV4_FORCE_IGMP_VERSION_MAX] = {
+ [IPV4_FORCE_IGMP_VERSION_NO] = "no",
+ [IPV4_FORCE_IGMP_VERSION_1] = "v1",
+ [IPV4_FORCE_IGMP_VERSION_2] = "v2",
+ [IPV4_FORCE_IGMP_VERSION_3] = "v3",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(ipv4_force_igmp_version, IPv4ForceIgmpVersion);
+DEFINE_CONFIG_PARSE_ENUM(config_parse_ipv4_force_igmp_version, ipv4_force_igmp_version, IPv4ForceIgmpVersion);
diff --git a/src/network/networkd-sysctl.h b/src/network/networkd-sysctl.h
index 1c19fbd2d6..ea1d2bc897 100644
--- a/src/network/networkd-sysctl.h
+++ b/src/network/networkd-sysctl.h
@@ -53,3 +53,18 @@ IPReversePathFilter ip_reverse_path_filter_from_string(const char *s) _pure_;
CONFIG_PARSER_PROTOTYPE(config_parse_ipv6_privacy_extensions);
CONFIG_PARSER_PROTOTYPE(config_parse_ip_reverse_path_filter);
CONFIG_PARSER_PROTOTYPE(config_parse_ip_forward_deprecated);
+
+typedef enum IPv4ForceIgmpVersion {
+ /* These values map to the kernel's /proc/sys/net/ipv4/conf/INTERFACE/force_igmp_version values. Do not reorder! */
+ IPV4_FORCE_IGMP_VERSION_NO = 0,
+ IPV4_FORCE_IGMP_VERSION_1 = 1,
+ IPV4_FORCE_IGMP_VERSION_2 = 2,
+ IPV4_FORCE_IGMP_VERSION_3 = 3,
+ _IPV4_FORCE_IGMP_VERSION_MAX,
+ _IPV4_FORCE_IGMP_VERSION_INVALID = -EINVAL,
+} IPv4ForceIgmpVersion;
+
+const char* ipv4_force_igmp_version_to_string(IPv4ForceIgmpVersion i) _const_;
+IPv4ForceIgmpVersion ipv4_force_igmp_version_from_string(const char *s) _pure_;
+
+CONFIG_PARSER_PROTOTYPE(config_parse_ipv4_force_igmp_version);
diff --git a/test/test-network/conf/25-sysctl.network b/test/test-network/conf/25-sysctl.network
index 759fe65fe8..dcc4f0d293 100644
--- a/test/test-network/conf/25-sysctl.network
+++ b/test/test-network/conf/25-sysctl.network
@@ -13,3 +13,4 @@ IPv6ProxyNDP=yes
IPv6AcceptRA=no
IPv4AcceptLocal=yes
IPv4ReversePathFilter=no
+MulticastIGMPVersion=v1
diff --git a/test/test-network/systemd-networkd-tests.py b/test/test-network/systemd-networkd-tests.py
index c7d75d8a67..8ee94a0294 100755
--- a/test/test-network/systemd-networkd-tests.py
+++ b/test/test-network/systemd-networkd-tests.py
@@ -4381,6 +4381,7 @@ class NetworkdNetworkTests(unittest.TestCase, Utilities):
self.check_ipv4_sysctl_attr('dummy98', 'proxy_arp_pvlan', '1')
self.check_ipv4_sysctl_attr('dummy98', 'accept_local', '1')
self.check_ipv4_sysctl_attr('dummy98', 'rp_filter', '0')
+ self.check_ipv4_sysctl_attr('dummy98', 'force_igmp_version', '1')
copy_network_unit('25-sysctl.network.d/25-ipv6-privacy-extensions.conf')
networkctl_reload()