mac80211: mesh portal functionality support

Currently the mesh code doesn't support bridging mesh point interfaces
with wired ethernet or AP to construct an MPP or MAP. This patch adds
code to support the "6 address frame format packet" functionality to
mesh point interfaces. Now the mesh network can be used as backhaul
for end to end communication.

Signed-off-by: Li YanBo <dreamfly281@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 38 insertions, 6 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 00d798cc9e04..00d96e63dce9 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1498,18 +1498,50 @@ int ieee80211_subif_start_xmit(struct sk_buff *skb,
 #ifdef CONFIG_MAC80211_MESH
         case NL80211_IFTYPE_MESH_POINT:
                 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
-                /* RA TA DA SA */
-                memset(hdr.addr1, 0, ETH_ALEN);
-                memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
-                memcpy(hdr.addr3, skb->data, ETH_ALEN);
-                memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
                 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
                         /* Do not send frames with mesh_ttl == 0 */
                         sdata->u.mesh.mshstats.dropped_frames_ttl++;
                         ret = 0;
                         goto fail;
                 }
-                meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, sdata);
+                memset(&mesh_hdr, 0, sizeof(mesh_hdr));
+
+                if (compare_ether_addr(dev->dev_addr,
+                                          skb->data + ETH_ALEN) == 0) {
+                        /* RA TA DA SA */
+                        memset(hdr.addr1, 0, ETH_ALEN);
+                        memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
+                        memcpy(hdr.addr3, skb->data, ETH_ALEN);
+                        memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
+                        meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, sdata);
+                } else {
+                        /* packet from other interface */
+                        struct mesh_path *mppath;
+
+                        memset(hdr.addr1, 0, ETH_ALEN);
+                        memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
+                        memcpy(hdr.addr4, dev->dev_addr, ETH_ALEN);
+
+                        if (is_multicast_ether_addr(skb->data))
+                                memcpy(hdr.addr3, skb->data, ETH_ALEN);
+                        else {
+                                rcu_read_lock();
+                                mppath = mpp_path_lookup(skb->data, sdata);
+                                if (mppath)
+                                        memcpy(hdr.addr3, mppath->mpp, ETH_ALEN);
+                                else
+                                        memset(hdr.addr3, 0xff, ETH_ALEN);
+                                rcu_read_unlock();
+                        }
+
+                        mesh_hdr.flags |= MESH_FLAGS_AE_A5_A6;
+                        mesh_hdr.ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
+                        put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &mesh_hdr.seqnum);
+                        memcpy(mesh_hdr.eaddr1, skb->data, ETH_ALEN);
+                        memcpy(mesh_hdr.eaddr2, skb->data + ETH_ALEN, ETH_ALEN);
+                        sdata->u.mesh.mesh_seqnum++;
+                        meshhdrlen = 18;
+                }
                 hdrlen = 30;
                 break;
 #endif