network: Add support to group links.

Link groups are similar to port ranges found in managed switches.
You can add network interfaces to a numbered group and perform operations
on all the interfaces from that group at once.

3 files changed, 53 insertions, 0 deletions

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index e261473f6f..32fe86045d 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -1825,6 +1825,53 @@ int link_down(Link *link, link_netlink_message_handler_t callback) {
         return 0;
 }
 
+static int link_group_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
+        int r;
+
+        assert(link);
+
+        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
+                return 1;
+
+        r = sd_netlink_message_get_errno(m);
+        if (r < 0)
+                log_link_message_warning_errno(link, m, r, "Could not set group for the interface");
+
+        return 1;
+}
+
+static int link_set_group(Link *link) {
+        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
+        int r;
+
+        assert(link);
+        assert(link->network);
+        assert(link->manager);
+        assert(link->manager->rtnl);
+
+        if (link->network->group <= 0)
+                return 0;
+
+        log_link_debug(link, "Setting group");
+
+        r = sd_rtnl_message_new_link(link->manager->rtnl, &req, RTM_SETLINK, link->ifindex);
+        if (r < 0)
+                return log_link_error_errno(link, r, "Could not allocate RTM_SETLINK message: %m");
+
+        r = sd_netlink_message_append_u32(req, IFLA_GROUP, link->network->group);
+        if (r < 0)
+                return log_link_error_errno(link, r, "Could not set link group: %m");
+
+        r = netlink_call_async(link->manager->rtnl, NULL, req, link_group_handler,
+                               link_netlink_destroy_callback, link);
+        if (r < 0)
+                return log_link_error_errno(link, r, "Could not send rtnetlink message: %m");
+
+        link_ref(link);
+
+        return 0;
+}
+
 static int link_handle_bound_to_list(Link *link) {
         Link *l;
         Iterator i;
@@ -2819,6 +2866,10 @@ static int link_configure(Link *link) {
         if (r < 0)
                 return r;
 
+        r = link_set_group(link);
+        if (r < 0)
+                return r;
+
         if (link_ipv4ll_enabled(link, ADDRESS_FAMILY_IPV4 | ADDRESS_FAMILY_FALLBACK_IPV4)) {
                 r = ipv4ll_configure(link);
                 if (r < 0)
diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf
index 7316ccffd0..d709633df3 100644
--- a/src/network/networkd-network-gperf.gperf
+++ b/src/network/networkd-network-gperf.gperf
@@ -46,6 +46,7 @@ Match.KernelVersion,                         config_parse_net_condition,
 Match.Architecture,                          config_parse_net_condition,                               CONDITION_ARCHITECTURE,        offsetof(Network, conditions)
 Link.MACAddress,                             config_parse_hwaddr,                                      0,                             offsetof(Network, mac)
 Link.MTUBytes,                               config_parse_mtu,                                         AF_UNSPEC,                     offsetof(Network, mtu)
+Link.Group,                                  config_parse_uint32,                                      0,                             offsetof(Network, group)
 Link.ARP,                                    config_parse_tristate,                                    0,                             offsetof(Network, arp)
 Link.Multicast,                              config_parse_tristate,                                    0,                             offsetof(Network, multicast)
 Link.AllMulticast,                           config_parse_tristate,                                    0,                             offsetof(Network, allmulticast)
diff --git a/src/network/networkd-network.h b/src/network/networkd-network.h
index 90fe222e12..092e58d42c 100644
--- a/src/network/networkd-network.h
+++ b/src/network/networkd-network.h
@@ -247,6 +247,7 @@ struct Network {
 
         struct ether_addr *mac;
         uint32_t mtu;
+        uint32_t group;
         int arp;
         int multicast;
         int allmulticast;