[libteam PATCH] teamd/lacp: silence ignore none LACP frames

[Hangbin Liu]

According to 802.3, Annex 43B, section 4, aside from LACP, the Slow
Protocol linktype is also to be used by other protocols, like 0x02 for
LAMP, 0x03 for OAM. So let's only check LACP frames. For none LACP
protocols, just silence ignore.

Signed-off-by: Hangbin Liu <liuhangbin(a)gmail.com&gt;
---
 teamd/teamd_runner_lacp.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/teamd/teamd_runner_lacp.c b/teamd/teamd_runner_lacp.c
index 11d02f1..9437f05 100644
--- a/teamd/teamd_runner_lacp.c
+++ b/teamd/teamd_runner_lacp.c
@@ -96,17 +96,27 @@ static void lacpdu_init(struct lacpdu *lacpdu)
 
 static bool lacpdu_check(struct lacpdu *lacpdu)
 {
+	/*
+	 * According to Annex 43B, section 4, aside from LACP, the Slow
+	 * Protocol linktype is also to be used by other protocols, like
+	 * 0x02 for LAMP, 0x03 for OAM. So for none LACP protocols, just
+	 * silence ignore.
+	 */
+	if (lacpdu->subtype != 0x01)
+		return false;
+
 	/*
 	 * According to 43.4.12 version_number, tlv_type and reserved fields
 	 * should not be checked.
 	 */
 
-	if (lacpdu->subtype		!= 0x01 ||
-	    lacpdu->actor_info_len	!= 0x14 ||
+	if (lacpdu->actor_info_len	!= 0x14 ||
 	    lacpdu->partner_info_len	!= 0x14 ||
 	    lacpdu->collector_info_len	!= 0x10 ||
-	    lacpdu->terminator_info_len	!= 0x00)
+	    lacpdu->terminator_info_len	!= 0x00) {
+		teamd_log_warn("malformed LACP PDU came.");
 		return false;
+	}
 	return true;
 }
 
@@ -1088,10 +1098,8 @@ static int lacpdu_recv(struct lacp_port *lacp_port)
 	if (!teamd_port_present(lacp_port->ctx, lacp_port->tdport))
 		return 0;
 
-	if (!lacpdu_check(&lacpdu)) {
-		teamd_log_warn("malformed LACP PDU came.");
+	if (!lacpdu_check(&lacpdu))
 		return 0;
-	}
 
 	/* Check if we have correct info about the other side */
 	if (memcmp(&lacpdu.actor, &lacp_port->partner,
-- 
2.25.4