Zebra: Restrict IPv6 RA to valid interfaces

Restrict interfaces on which IPv6 Router Advertisements are allowed. The list
excludes loopback interfaces including the VRF device interface; specific to
Cumulus, it also includes "switch0" and "ethX" interfaces.

Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Reviewed-by:   Don Slice <dslice@cumulusnetworks.com>

Ticket: CM-9849
Reviewed By: CCR-4334
Testing Done: Manual

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/if.h b/lib/if.h
index a8e674765f..797a68bf82 100644
--- a/lib/if.h
+++ b/lib/if.h
@@ -91,6 +91,7 @@ struct interface
 #define ZEBRA_INTERFACE_ACTIVE     (1 << 0)
 #define ZEBRA_INTERFACE_SUB        (1 << 1)
 #define ZEBRA_INTERFACE_LINKDETECTION (1 << 2)
+#define ZEBRA_INTERFACE_VRF_LOOPBACK (1 << 3)
 
   /* Interface flags. */
   uint64_t flags;