proto-shell: Support teardown on layer 3 link loss

Commit c6858766 added interface teardown support on layer 3 device link loss
mainly for shell protocols who have no proto task like xl2tp. However for
shell protocols having a proto task it is not always the correct action to
teardown the interface; as an example the PPP daemon can be put into
persist state trying to re-establish the link via a hold-off mechanism
if layer 3 link loss is detected.
Therefore shell handlers can enable via TEARDOWN_ON_L3_LINK_DOWN a proto
flag which will teardown the interface when layer 3 link loss is detected

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/proto.h b/proto.h
index 87dec4e..8f50fdc 100644
--- a/proto.h
+++ b/proto.h
@@ -38,6 +38,7 @@ enum {
 	PROTO_FLAG_RENEW_AVAILABLE = (1 << 3),
 	PROTO_FLAG_FORCE_LINK_DEFAULT = (1 << 4),
 	PROTO_FLAG_LASTERROR = (1 << 5),
+	PROTO_FLAG_TEARDOWN_ON_L3_LINK_DOWN = (1 << 6),
 };
 
 struct interface_proto_state {