mac80211: clean up eapol frame handling/port control

This cleans up the eapol frame handling and some related code in the
receive and transmit paths. After this patch
 * EAPOL frames addressed to us or the EAPOL group address are
   always accepted regardless of whether they are encrypted or not
 * other frames from a station are dropped if PAE is enabled and
   the station is not authorized
 * unencrypted frames (except the EAPOL frames above) are dropped if
   drop_unencrypted is enabled
 * some superfluous code that eth_type_trans handles anyway is gone
 * port control is done for transmitted packets

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 33 insertions, 20 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 4655e3038658..6dbd91842881 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -261,18 +261,6 @@ ieee80211_tx_h_check_assoc(struct ieee80211_txrx_data *tx)
                 return TXRX_CONTINUE;
         }
 
-        if (unlikely(/* !injected && */ tx->sdata->ieee802_1x &&
-                     !(sta_flags & WLAN_STA_AUTHORIZED))) {
-#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
-                DECLARE_MAC_BUF(mac);
-                printk(KERN_DEBUG "%s: dropped frame to %s"
-                       " (unauthorized port)\n", tx->dev->name,
-                       print_mac(mac, hdr->addr1));
-#endif
-                I802_DEBUG_INC(tx->local->tx_handlers_drop_unauth_port);
-                return TXRX_DROP;
-        }
-
         return TXRX_CONTINUE;
 }
 
@@ -449,8 +437,7 @@ ieee80211_tx_h_select_key(struct ieee80211_txrx_data *tx)
         else if ((key = rcu_dereference(tx->sdata->default_key)))
                 tx->key = key;
         else if (tx->sdata->drop_unencrypted &&
-                 !(tx->sdata->eapol &&
-                   ieee80211_is_eapol(tx->skb, ieee80211_get_hdrlen(fc)))) {
+                 !ieee80211_is_eapol(tx->skb, ieee80211_get_hdrlen(fc))) {
                 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
                 return TXRX_DROP;
         } else {
@@ -1346,6 +1333,7 @@ int ieee80211_subif_start_xmit(struct sk_buff *skb,
         int encaps_len, skip_header_bytes;
         int nh_pos, h_pos;
         struct sta_info *sta;
+        u32 sta_flags = 0;
 
         sdata = IEEE80211_DEV_TO_SUB_IF(dev);
         if (unlikely(skb->len < ETH_HLEN)) {
@@ -1361,7 +1349,6 @@ int ieee80211_subif_start_xmit(struct sk_buff *skb,
         /* convert Ethernet header to proper 802.11 header (based on
          * operation mode) */
         ethertype = (skb->data[12] << 8) | skb->data[13];
-        /* TODO: handling for 802.1x authorized/unauthorized port */
         fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;
 
         switch (sdata->type) {
@@ -1403,16 +1390,42 @@ int ieee80211_subif_start_xmit(struct sk_buff *skb,
                 goto fail;
         }
 
-        /* receiver is QoS enabled, use a QoS type frame */
         sta = sta_info_get(local, hdr.addr1);
         if (sta) {
-                if (sta->flags & WLAN_STA_WME) {
-                        fc |= IEEE80211_STYPE_QOS_DATA;
-                        hdrlen += 2;
-                }
+                sta_flags = sta->flags;
                 sta_info_put(sta);
         }
 
+        /* receiver is QoS enabled, use a QoS type frame */
+        if (sta_flags & WLAN_STA_WME) {
+                fc |= IEEE80211_STYPE_QOS_DATA;
+                hdrlen += 2;
+        }
+
+        /*
+         * If port access control is enabled, drop frames to unauthorised
+         * stations unless they are EAPOL frames from the local station.
+         */
+        if (unlikely(sdata->ieee802_1x_pac &&
+                     !(sta_flags & WLAN_STA_AUTHORIZED) &&
+                     !(ethertype == ETH_P_PAE &&
+                       compare_ether_addr(dev->dev_addr,
+                                          skb->data + ETH_ALEN) == 0))) {
+#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
+                DECLARE_MAC_BUF(mac);
+
+                if (net_ratelimit())
+                        printk(KERN_DEBUG "%s: dropped frame to %s"
+                               " (unauthorized port)\n", dev->name,
+                               print_mac(mac, hdr.addr1));
+#endif
+
+                I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
+
+                ret = 0;
+                goto fail;
+        }
+
         hdr.frame_control = cpu_to_le16(fc);
         hdr.duration_id = 0;
         hdr.seq_ctrl = 0;