FDP seems to use a non-flawed checksum

diff --git a/src/cdp.c b/src/cdp.c
index 554448b50c99f7339a30fd2e9aa68d9aae3d445a..55c6622445bed374b517d810bb763bf7172d0484 100644 (file)
--- a/src/cdp.c
+++ b/src/cdp.c
@@ -192,7 +192,7 @@ cdp_send(struct lldpd *global, struct lldpd_chassis *chassis,
        }
        len -= sizeof(struct ieee8023);
        llc.ether.size = htons(len);
-       ch.checksum = iov_checksum(&iov[1], c - 1, 1);
+       ch.checksum = iov_checksum(&iov[1], c - 1, (version != 0) ? 1 : 0);
 
        if (writev((hardware->h_raw_real > 0) ? hardware->h_raw_real :
                   hardware->h_raw, iov, c) == -1) {
@@ -291,7 +291,13 @@ cdp_decode(struct lldpd *cfg, char *frame, int s,
        chassis->c_ttl = ntohs(ch->ttl);
        iov.iov_len = s - f;
        iov.iov_base = frame + f;
-       cksum = iov_checksum(&iov, 1, 1);
+       cksum = iov_checksum(&iov, 1,
+#ifdef ENABLE_FDP
+           !fdp                /* fdp = 0 -> cisco checksum */
+#else
+           1                   /* cisco checksum */
+#endif
+               );
        /* An off-by-one error may happen. Just ignore it */
        if ((cksum != 0) && (cksum != 0xfffe)) {
                LLOG_INFO("incorrect CDP/FDP checksum for frame received on %s (%d)",