[PATCH] ieee80211_rx_any: filter out packets, call ieee80211_rx or ieee80211_rx_mgt

Version 2 of the patch. Added checks for version 0
and proper from/to DS bits. Even in promisc
mode we won't receive packets from another BSSes.

bcm43xx_rx() contains code to filter out packets from
foreign BSSes and decide whether to call ieee80211_rx
or ieee80211_rx_mgt. This is not bcm specific.

Patch adapts that code and adds it to 80211
as ieee80211_rx_any() function.

Signed-off-by: Denis Vlasenko <vda@ilport.com.ua>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/ieee80211/ieee80211_rx.c b/net/ieee80211/ieee80211_rx.c
index a7f2a642a512320b39871cbce6f7ae42da44a441..604b7b0097bce98dd71f120b77a86ad9363fa438 100644 (file)
--- a/net/ieee80211/ieee80211_rx.c
+++ b/net/ieee80211/ieee80211_rx.c
@@ -780,6 +780,80 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
        return 0;
 }
 
+/* Filter out unrelated packets, call ieee80211_rx[_mgt] */
+int ieee80211_rx_any(struct ieee80211_device *ieee,
+                    struct sk_buff *skb, struct ieee80211_rx_stats *stats)
+{
+       struct ieee80211_hdr_4addr *hdr;
+       int is_packet_for_us;
+       u16 fc;
+
+       if (ieee->iw_mode == IW_MODE_MONITOR)
+               return ieee80211_rx(ieee, skb, stats) ? 0 : -EINVAL;
+
+       hdr = (struct ieee80211_hdr_4addr *)skb->data;
+       fc = le16_to_cpu(hdr->frame_ctl);
+
+       if ((fc & IEEE80211_FCTL_VERS) != 0)
+               return -EINVAL;
+               
+       switch (fc & IEEE80211_FCTL_FTYPE) {
+       case IEEE80211_FTYPE_MGMT:
+               ieee80211_rx_mgt(ieee, hdr, stats);
+               return 0;
+       case IEEE80211_FTYPE_DATA:
+               break;
+       case IEEE80211_FTYPE_CTL:
+               return 0;
+       default:
+               return -EINVAL;
+       }
+
+       is_packet_for_us = 0;
+       switch (ieee->iw_mode) {
+       case IW_MODE_ADHOC:
+               /* our BSS and not from/to DS */
+               if (memcmp(hdr->addr3, ieee->bssid, ETH_ALEN) == 0)
+               if ((fc & (IEEE80211_FCTL_TODS+IEEE80211_FCTL_FROMDS)) == 0) {
+                       /* promisc: get all */
+                       if (ieee->dev->flags & IFF_PROMISC)
+                               is_packet_for_us = 1;
+                       /* to us */
+                       else if (memcmp(hdr->addr1, ieee->dev->dev_addr, ETH_ALEN) == 0)
+                               is_packet_for_us = 1;
+                       /* mcast */
+                       else if (is_multicast_ether_addr(hdr->addr1))
+                               is_packet_for_us = 1;
+               }
+               break;
+       case IW_MODE_INFRA:
+               /* our BSS (== from our AP) and from DS */
+               if (memcmp(hdr->addr2, ieee->bssid, ETH_ALEN) == 0)
+               if ((fc & (IEEE80211_FCTL_TODS+IEEE80211_FCTL_FROMDS)) == IEEE80211_FCTL_FROMDS) {
+                       /* promisc: get all */
+                       if (ieee->dev->flags & IFF_PROMISC)
+                               is_packet_for_us = 1;
+                       /* to us */
+                       else if (memcmp(hdr->addr1, ieee->dev->dev_addr, ETH_ALEN) == 0)
+                               is_packet_for_us = 1;
+                       /* mcast */
+                       else if (is_multicast_ether_addr(hdr->addr1)) {
+                               /* not our own packet bcasted from AP */
+                               if (memcmp(hdr->addr3, ieee->dev->dev_addr, ETH_ALEN))
+                                       is_packet_for_us = 1;
+                       }
+               }
+               break;
+       default:
+               /* ? */
+               break;
+       }
+
+       if (is_packet_for_us)
+               return (ieee80211_rx(ieee, skb, stats) ? 0 : -EINVAL);
+       return 0;
+}
+
 #define MGMT_FRAME_FIXED_PART_LENGTH           0x24
 
 static u8 qos_oui[QOS_OUI_LEN] = { 0x00, 0x50, 0xF2 };