ofproto-dpif-xlate: Identify STP BPDUs more specifically.

Apart from STP, EVB extension of LLDP as well as IEEE 802.1QBG use the
Nearest Customer Bridge (NCB) DMAC which has a value of 0180.c200.0000.
STP can be distinguished by Ethertype from these protocols.

Signed-off-by: Padmanabhan Krishnan <kprad1@yahoo.com>
[blp@nicira.com rewrote the details of the patch]
Signed-off-by: Ben Pfaff <blp@nicira.com>
Tested-by: Padmanabhan Krishnan <kprad1@yahoo.com>

diff --git a/AUTHORS b/AUTHORS
index 4881c25..16255d4 100644 (file)
--- a/AUTHORS
+++ b/AUTHORS
@@ -86,6 +86,7 @@ Murphy McCauley         murphy.mccauley@gmail.com
 Natasha Gude            natasha@nicira.com
 Neil McKee              neil.mckee@inmon.com
 Neil Zhu                zhuj@centecnetworks.com
+Padmanabhan Krishnan    kprad1@yahoo.com
 Paraneetharan Chandrasekaran    paraneetharanc@gmail.com
 Paul Fazzone            pfazzone@nicira.com
 Paul Ingram             paul@nicira.com
@@ -225,7 +226,6 @@ Min Chen                ustcer.tonychan@gmail.com
 Mikael Doverhag         mdoverhag@nicira.com
 Nagi Reddy Jonnala      njonnala@Brocade.com
 Niklas Andersson        nandersson@nicira.com
-Padmanabhan Krishnan    kprad1@yahoo.com
 Pankaj Thakkar          thakkar@nicira.com
 Pasi Kärkkäinen         pasik@iki.fi
 Paulo Cravero           pcravero@as2594.net

diff --git a/lib/flow.h b/lib/flow.h
index 413ecb5..e63e4e2 100644 (file)
--- a/lib/flow.h
+++ b/lib/flow.h
@@ -617,4 +617,10 @@ static inline bool is_icmpv6(const struct flow *flow)
             && flow->nw_proto == IPPROTO_ICMPV6);
 }
 
+static inline bool is_stp(const struct flow *flow)
+{
+    return (eth_addr_equals(flow->dl_dst, eth_addr_stp)
+            && flow->dl_type == htons(FLOW_DL_TYPE_NONE));
+}
+
 #endif /* flow.h */

diff --git a/ofproto/ofproto-dpif-xlate.c b/ofproto/ofproto-dpif-xlate.c
index 6a56a15..4a9ba52 100644 (file)
--- a/ofproto/ofproto-dpif-xlate.c
+++ b/ofproto/ofproto-dpif-xlate.c
@@ -770,8 +770,9 @@ xport_stp_listen_state(const struct xport *xport)
 static bool
 stp_should_process_flow(const struct flow *flow, struct flow_wildcards *wc)
 {
+    /* is_stp() also checks dl_type, but dl_type is always set in 'wc'. */
     memset(&wc->masks.dl_dst, 0xff, sizeof wc->masks.dl_dst);
-    return eth_addr_equals(flow->dl_dst, eth_addr_stp);
+    return is_stp(flow);
 }
 
 static void
@@ -1820,7 +1821,7 @@ compose_output_action__(struct xlate_ctx *ctx, ofp_port_t ofp_port,
         xlate_report(ctx, "OFPPC_NO_FWD set, skipping output");
         return;
     } else if (check_stp) {
-        if (eth_addr_equals(ctx->base_flow.dl_dst, eth_addr_stp)) {
+        if (is_stp(&ctx->base_flow)) {
             if (!xport_stp_listen_state(xport)) {
                 xlate_report(ctx, "STP not in listening state, "
                              "skipping bpdu output");
@@ -2724,7 +2725,7 @@ xlate_sample_action(struct xlate_ctx *ctx,
 static bool
 may_receive(const struct xport *xport, struct xlate_ctx *ctx)
 {
-    if (xport->config & (eth_addr_equals(ctx->xin->flow.dl_dst, eth_addr_stp)
+    if (xport->config & (is_stp(&ctx->xin->flow)
                          ? OFPUTIL_PC_NO_RECV_STP
                          : OFPUTIL_PC_NO_RECV)) {
         return false;