From 3a92a5b6a6c50992ff9f30d1c970381bbe54a942 Mon Sep 17 00:00:00 2001
From: Ben Pfaff <blp@nicira.com>
Date: Thu, 1 Jan 2009 14:42:10 -0800
Subject: [PATCH] vswitchd: Add support for untagged VLAN ports in VLAN 0.

---
 vswitchd/bridge.c        | 20 +++++++++-----------
 vswitchd/vswitchd.conf.5 |  5 ++++-
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/vswitchd/bridge.c b/vswitchd/bridge.c
index c19e2cbf..447a8819 100644
--- a/vswitchd/bridge.c
+++ b/vswitchd/bridge.c
@@ -115,7 +115,7 @@ struct mirror {
 struct port {
     struct bridge *bridge;
     size_t port_idx;
-    int vlan;                   /* 0=trunk port, otherwise a 12-bit VLAN ID. */
+    int vlan;                   /* -1=trunk port, else a 12-bit VLAN ID. */
     unsigned long *trunks;      /* Trunked VLANs, if 'vlan' == 0. */
     const char *name;
 
@@ -1262,8 +1262,8 @@ set_dst(struct ft_dst *p, const struct flow *flow,
         const struct port *in_port, const struct port *out_port,
         tag_type *tags)
 {
-    p->vlan = (out_port->vlan ? OFP_VLAN_NONE
-              : in_port->vlan ? in_port->vlan
+    p->vlan = (out_port->vlan >= 0 ? OFP_VLAN_NONE
+              : in_port->vlan >= 0 ? in_port->vlan
               : ntohs(flow->dl_vlan));
     return choose_output_iface(out_port, flow, &p->dp_ifidx, tags);
 }
@@ -1366,7 +1366,7 @@ dst_is_duplicate(const struct ft_dst *dsts, size_t n_dsts,
 static bool
 port_trunks_vlan(const struct port *port, uint16_t vlan)
 {
-    return !port->vlan && bitmap_is_set(port->trunks, vlan);
+    return port->vlan < 0 && bitmap_is_set(port->trunks, vlan);
 }
 
 static bool
@@ -1415,7 +1415,7 @@ compose_dsts(const struct bridge *br, const struct flow *flow, uint16_t vlan,
                         && set_dst(dst, flow, in_port, port, tags)
                         && !dst_is_duplicate(dsts, dst - dsts, dst))
                     {
-                        if (!port->vlan) {
+                        if (port->vlan < 0) {
                             dst->vlan = m->out_vlan;
                         }
                         if (dst->dp_ifidx == ntohs(flow->in_port)) {
@@ -1588,7 +1588,7 @@ process_flow(struct bridge *br, const struct flow *flow,
     if (vlan == OFP_VLAN_NONE) {
         vlan = 0;
     }
-    if (in_port->vlan) {
+    if (in_port->vlan >= 0) {
         if (vlan) {
             /* XXX support double tagging? */
             if (pkt->buf) {
@@ -2211,7 +2211,7 @@ port_create(struct bridge *br, const char *name)
     port = xcalloc(1, sizeof *port);
     port->bridge = br;
     port->port_idx = br->n_ports;
-    port->vlan = 0;
+    port->vlan = -1;
     port->trunks = NULL;
     port->name = xstrdup(name);
     port->active_iface = -1;
@@ -2281,14 +2281,12 @@ port_reconfigure(struct port *port)
     }
 
     /* Get VLAN tag. */
-    vlan = 0;
+    vlan = -1;
     if (cfg_has("vlan.%s.tag", port->name)) {
         if (!bonded) {
             vlan = cfg_get_vlan(0, "vlan.%s.tag", port->name);
             if (vlan >= 0 && vlan <= 4095) {
                 VLOG_DBG("port %s: assigning VLAN tag %d", port->name, vlan);
-            } else {
-                vlan = 0;
             }
         } else {
             /* It's possible that bonded, VLAN-tagged ports make sense.  Maybe
@@ -2304,7 +2302,7 @@ port_reconfigure(struct port *port)
 
     /* Get trunked VLANs. */
     trunks = NULL;
-    if (!vlan) {
+    if (vlan < 0) {
         size_t n_trunks, n_errors;
         size_t i;
 
diff --git a/vswitchd/vswitchd.conf.5 b/vswitchd/vswitchd.conf.5
index 06721a46..121cb545 100644
--- a/vswitchd/vswitchd.conf.5
+++ b/vswitchd/vswitchd.conf.5
@@ -108,7 +108,7 @@ carries VLANs 1, 2, and 3:
 .PP
 A bridge port may be configured with an implicit, untagged VLAN.  
 Define key
-\fBvlan.\fIport\fB.tag\fR to an integer value \fIvid\fR between 1 and
+\fBvlan.\fIport\fB.tag\fR to an integer value \fIvid\fR between 0 and
 4095, inclusive, to designate the named \fIport\fR as a member
 of 802.1Q VLAN \fIvid\fR.  When \fIport\fR is assigned a VLAN tag this
 way, frames arriving on trunk ports will be forwarded to \fIport\fR
@@ -117,6 +117,9 @@ other VLAN ports will be forwarded to \fIport\fR only if their
 \fIvid\fR values are equal.  Frames forwarded to \fIport\fR will not
 have an 802.1Q header.
 .PP
+When \fIvid\fR is 0, frames arriving on trunk ports without an 802.1Q
+VLAN header will also be forwarded to \fIport\fR.
+.PP
 When a frame with a 802.1Q header that indicates a nonzero VLAN is
 received on an implicit VLAN port, it is discarded.
 .PP
-- 
2.30.2