Merge git://oss.sgi.com:8090/xfs/xfs-2.6
[linux-drm-fsl-dcu.git] / net / ieee80211 / ieee80211_rx.c
index 72d4d4e04d426b26d8f323f4522432337f4691e7..4084909f6f924220becc534f557d5ab778ad6bb9 100644 (file)
@@ -415,17 +415,16 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
            ieee->host_mc_decrypt : ieee->host_decrypt;
 
        if (can_be_decrypted) {
-               int idx = 0;
                if (skb->len >= hdrlen + 3) {
                        /* Top two-bits of byte 3 are the key index */
-                       idx = skb->data[hdrlen + 3] >> 6;
+                       keyidx = skb->data[hdrlen + 3] >> 6;
                }
 
-               /* ieee->crypt[] is WEP_KEY (4) in length.  Given that idx
-                * is only allowed 2-bits of storage, no value of idx can
-                * be provided via above code that would result in idx
+               /* ieee->crypt[] is WEP_KEY (4) in length.  Given that keyidx
+                * is only allowed 2-bits of storage, no value of keyidx can
+                * be provided via above code that would result in keyidx
                 * being out of range */
-               crypt = ieee->crypt[idx];
+               crypt = ieee->crypt[keyidx];
 
 #ifdef NOT_YET
                sta = NULL;
@@ -479,6 +478,11 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
                        goto rx_exit;
        }
 #endif
+       /* drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.29) */
+       if (sc == ieee->prev_seq_ctl)
+               goto rx_dropped;
+       else
+               ieee->prev_seq_ctl = sc;
 
        /* Data frame - extract src/dst addresses */
        if (skb->len < IEEE80211_3ADDR_LEN)
@@ -655,6 +659,51 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
                goto rx_dropped;
        }
 
+       /* If the frame was decrypted in hardware, we may need to strip off
+        * any security data (IV, ICV, etc) that was left behind */
+       if (!can_be_decrypted && (fc & IEEE80211_FCTL_PROTECTED) &&
+           ieee->host_strip_iv_icv) {
+               int trimlen = 0;
+
+               /* Top two-bits of byte 3 are the key index */
+               if (skb->len >= hdrlen + 3)
+                       keyidx = skb->data[hdrlen + 3] >> 6;
+
+               /* To strip off any security data which appears before the
+                * payload, we simply increase hdrlen (as the header gets
+                * chopped off immediately below). For the security data which
+                * appears after the payload, we use skb_trim. */
+
+               switch (ieee->sec.encode_alg[keyidx]) {
+               case SEC_ALG_WEP:
+                       /* 4 byte IV */
+                       hdrlen += 4;
+                       /* 4 byte ICV */
+                       trimlen = 4;
+                       break;
+               case SEC_ALG_TKIP:
+                       /* 4 byte IV, 4 byte ExtIV */
+                       hdrlen += 8;
+                       /* 8 byte MIC, 4 byte ICV */
+                       trimlen = 12;
+                       break;
+               case SEC_ALG_CCMP:
+                       /* 8 byte CCMP header */
+                       hdrlen += 8;
+                       /* 8 byte MIC */
+                       trimlen = 8;
+                       break;
+               }
+
+               if (skb->len < trimlen)
+                       goto rx_dropped;
+
+               __skb_trim(skb, skb->len - trimlen);
+
+               if (skb->len < hdrlen)
+                       goto rx_dropped;
+       }
+
        /* skb: hdr + (possible reassembled) full plaintext payload */
 
        payload = skb->data + hdrlen;
@@ -779,33 +828,44 @@ 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,
+/* Filter out unrelated packets, call ieee80211_rx[_mgt]
+ * This function takes over the skb, it should not be used again after calling
+ * this function. */
+void 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;
+       if (ieee->iw_mode == IW_MODE_MONITOR) {
+               if (!ieee80211_rx(ieee, skb, stats))
+                       dev_kfree_skb_irq(skb);
+               return;
+       }
+
+       if (skb->len < sizeof(struct ieee80211_hdr))
+               goto drop_free;
 
        hdr = (struct ieee80211_hdr_4addr *)skb->data;
        fc = le16_to_cpu(hdr->frame_ctl);
 
        if ((fc & IEEE80211_FCTL_VERS) != 0)
-               return -EINVAL;
-               
+               goto drop_free;
+
        switch (fc & IEEE80211_FCTL_FTYPE) {
        case IEEE80211_FTYPE_MGMT:
+               if (skb->len < sizeof(struct ieee80211_hdr_3addr))
+                       goto drop_free;
                ieee80211_rx_mgt(ieee, hdr, stats);
-               return 0;
+               dev_kfree_skb_irq(skb);
+               return;
        case IEEE80211_FTYPE_DATA:
                break;
        case IEEE80211_FTYPE_CTL:
-               return 0;
+               return;
        default:
-               return -EINVAL;
+               return;
        }
 
        is_packet_for_us = 0;
@@ -849,8 +909,14 @@ int ieee80211_rx_any(struct ieee80211_device *ieee,
        }
 
        if (is_packet_for_us)
-               return (ieee80211_rx(ieee, skb, stats) ? 0 : -EINVAL);
-       return 0;
+               if (!ieee80211_rx(ieee, skb, stats))
+                       dev_kfree_skb_irq(skb);
+       return;
+
+drop_free:
+       dev_kfree_skb_irq(skb);
+       ieee->stats.rx_dropped++;
+       return;
 }
 
 #define MGMT_FRAME_FIXED_PART_LENGTH           0x24
@@ -1067,7 +1133,10 @@ static int ieee80211_parse_info_param(struct ieee80211_info_element
                                             info_element->len +
                                             sizeof(*info_element),
                                             length, info_element->id);
-                       return 1;
+                       /* We stop processing but don't return an error here
+                        * because some misbehaviour APs break this rule. ie.
+                        * Orinoco AP1000. */
+                       break;
                }
 
                switch (info_element->id) {
@@ -1166,6 +1235,7 @@ static int ieee80211_parse_info_param(struct ieee80211_info_element
 
                case MFIE_TYPE_ERP_INFO:
                        network->erp_value = info_element->data[0];
+                       network->flags |= NETWORK_HAS_ERP_VALUE;
                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_ERP_SET: %d\n",
                                             network->erp_value);
                        break;
@@ -1234,12 +1304,11 @@ static int ieee80211_parse_info_param(struct ieee80211_info_element
                case MFIE_TYPE_IBSS_DFS:
                        if (network->ibss_dfs)
                                break;
-                       network->ibss_dfs =
-                           kmalloc(info_element->len, GFP_ATOMIC);
+                       network->ibss_dfs = kmemdup(info_element->data,
+                                                   info_element->len,
+                                                   GFP_ATOMIC);
                        if (!network->ibss_dfs)
                                return 1;
-                       memcpy(network->ibss_dfs, info_element->data,
-                              info_element->len);
                        network->flags |= NETWORK_HAS_IBSS_DFS;
                        break;
 
@@ -1420,7 +1489,7 @@ static void update_network(struct ieee80211_network *dst,
 
        /* We only update the statistics if they were created by receiving
         * the network information on the actual channel the network is on.
-        * 
+        *
         * This keeps beacons received on neighbor channels from bringing
         * down the signal level of an AP. */
        if (dst->channel == src->stats.received_channel)
@@ -1729,5 +1798,6 @@ void ieee80211_rx_mgt(struct ieee80211_device *ieee,
        }
 }
 
+EXPORT_SYMBOL_GPL(ieee80211_rx_any);
 EXPORT_SYMBOL(ieee80211_rx_mgt);
 EXPORT_SYMBOL(ieee80211_rx);