networkd: add support to configure NOARP/ARP for interface (#3854)

https://lists.freedesktop.org/archives/systemd-devel/2016-August/037268.html

1 files changed, 63 insertions, 0 deletions

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 99784b0ebe..3e10ab1e04 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -1314,6 +1314,65 @@ int link_set_mtu(Link *link, uint32_t mtu) {
         return 0;
 }
 
+static int set_flags_handler(sd_netlink *rtnl, sd_netlink_message *m, void *userdata) {
+        _cleanup_link_unref_ Link *link = userdata;
+        int r;
+
+        assert(m);
+        assert(link);
+        assert(link->ifname);
+
+        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_warning_errno(link, r, "Could not set link flags: %m");
+
+        return 1;
+}
+
+static int link_set_flags(Link *link) {
+        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
+        unsigned ifi_change = 0;
+        unsigned ifi_flags = 0;
+        int r;
+
+        assert(link);
+        assert(link->manager);
+        assert(link->manager->rtnl);
+
+        if (link->flags & IFF_LOOPBACK)
+                return 0;
+
+        if (!link->network)
+                return 0;
+
+        if (link->network->arp < 0)
+                return 0;
+
+        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");
+
+        if (link->network->arp >= 0) {
+                ifi_change |= IFF_NOARP;
+                ifi_flags |= IFF_NOARP;
+        }
+
+        r = sd_rtnl_message_link_set_flags(req, ifi_flags, ifi_change);
+        if (r < 0)
+                return log_link_error_errno(link, r, "Could not set link flags: %m");
+
+        r = sd_netlink_call_async(link->manager->rtnl, req, set_flags_handler, link, 0, NULL);
+        if (r < 0)
+                return log_link_error_errno(link, r, "Could not send rtnetlink message: %m");
+
+        link_ref(link);
+
+        return 0;
+}
+
 static int link_set_bridge(Link *link) {
         _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
         int r;
@@ -2411,6 +2470,10 @@ static int link_configure(Link *link) {
         if (r < 0)
                 return r;
 
+        r = link_set_flags(link);
+        if (r < 0)
+                return r;
+
         if (link_ipv4ll_enabled(link)) {
                 r = ipv4ll_configure(link);
                 if (r < 0)