bfdd: Some interfaces don't have mac addresses

When an interface does not have a mac address, don't
try to retrieve the mac address ( for it to just fail ).

Example interface:
sharpd@eva [2]> ip link show tun100
21: tun100@NONE: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1480 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/ipip 192.168.119.224 peer 192.168.119.120

Let's just notice that there is a NOARP flag and abort the call.

Fixes: #11733
Signed-off-by: Donald Sharp <sharpd@nvidia.com>

diff --git a/bfdd/bfd_packet.c b/bfdd/bfd_packet.c
index 82b3f09b0cb6321027abcea6d022b8a74e562ea3..e2a44bce76102a8f01c5f487ce8e2c884d37bce3 100644 (file)
--- a/bfdd/bfd_packet.c
+++ b/bfdd/bfd_packet.c
@@ -1683,6 +1683,8 @@ void bfd_peer_mac_set(int sd, struct bfd_session *bfd,
 
        if (CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_MAC_SET))
                return;
+       if (ifp->flags & IFF_NOARP)
+               return;
 
        if (peer->sa_sin.sin_family == AF_INET) {
                /* IPV4 */
@@ -1696,8 +1698,9 @@ void bfd_peer_mac_set(int sd, struct bfd_session *bfd,
                strlcpy(arpreq_.arp_dev, ifp->name, sizeof(arpreq_.arp_dev));
 
                if (ioctl(sd, SIOCGARP, &arpreq_) < 0) {
-                       zlog_warn("BFD: getting peer's mac failed error %s",
-                                 strerror(errno));
+                       zlog_warn(
+                               "BFD: getting peer's mac on %s failed error %s",
+                               ifp->name, strerror(errno));
                        UNSET_FLAG(bfd->flags, BFD_SESS_FLAG_MAC_SET);
                        memset(bfd->peer_hw_addr, 0, sizeof(bfd->peer_hw_addr));