From: Vincent Bernat <bernat@luffy.cx>
Date: Thu, 5 Dec 2013 20:37:04 +0000 (+0100)
Subject: lldp: do not send system description TLV if empty
X-Git-Tag: 0.7.8~62
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d798504262549e68c9a1801687bbcef907b21699;p=thirdparty%2Flldpd.git

lldp: do not send system description TLV if empty

This makes this TLV optional to send (as authorized in 802.1AB). The
user just has to provide an empty TLV, with, for example `-S ""`.
---

diff --git a/src/daemon/lldp.c b/src/daemon/lldp.c
index 38403aa9..6e5806ad 100644
--- a/src/daemon/lldp.c
+++ b/src/daemon/lldp.c
@@ -129,12 +129,14 @@ lldp_send(struct lldpd *global,
 	      POKE_END_LLDP_TLV))
 		goto toobig;
 
-	/* System description */
-	if (!(
-	      POKE_START_LLDP_TLV(LLDP_TLV_SYSTEM_DESCR) &&
-	      POKE_BYTES(chassis->c_descr, strlen(chassis->c_descr)) &&
-	      POKE_END_LLDP_TLV))
-		goto toobig;
+	/* System description (skip it if empty) */
+	if (chassis->c_descr && *chassis->c_descr != '\0') {
+		if (!(
+			    POKE_START_LLDP_TLV(LLDP_TLV_SYSTEM_DESCR) &&
+			    POKE_BYTES(chassis->c_descr, strlen(chassis->c_descr)) &&
+			    POKE_END_LLDP_TLV))
+			goto toobig;
+	}
 
 	/* System capabilities */
 	if (!(