[TCP]: Reduce sacked_out with reno when purging write_queue
[safe/jmp/linux-2.6] / net / ieee80211 / ieee80211_rx.c
index 6b8469d..6284c99 100644 (file)
@@ -3,8 +3,8 @@
  * for Intersil Prism2/2.5/3 - hostap.o module, common routines
  *
  * Copyright (c) 2001-2002, SSH Communications Security Corp and Jouni Malinen
- * <jkmaline@cc.hut.fi>
- * Copyright (c) 2002-2003, Jouni Malinen <jkmaline@cc.hut.fi>
+ * <j@w1.fi>
+ * Copyright (c) 2002-2003, Jouni Malinen <j@w1.fi>
  * Copyright (c) 2004-2005, Intel Corporation
  *
  * This program is free software; you can redistribute it and/or modify
@@ -14,7 +14,6 @@
  */
 
 #include <linux/compiler.h>
-#include <linux/config.h>
 #include <linux/errno.h>
 #include <linux/if_arp.h>
 #include <linux/in6.h>
@@ -43,7 +42,7 @@ static void ieee80211_monitor_rx(struct ieee80211_device *ieee,
        u16 fc = le16_to_cpu(hdr->frame_ctl);
 
        skb->dev = ieee->dev;
-       skb->mac.raw = skb->data;
+       skb_reset_mac_header(skb);
        skb_pull(skb, ieee80211_get_hdrlen(fc));
        skb->pkt_type = PACKET_OTHERHOST;
        skb->protocol = __constant_htons(ETH_P_80211_RAW);
@@ -367,6 +366,12 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
        frag = WLAN_GET_SEQ_FRAG(sc);
        hdrlen = ieee80211_get_hdrlen(fc);
 
+       if (skb->len < hdrlen) {
+               printk(KERN_INFO "%s: invalid SKB length %d\n",
+                       dev->name, skb->len);
+               goto rx_dropped;
+       }
+
        /* Put this code here so that we avoid duplicating it in all
         * Rx paths. - Jean II */
 #ifdef CONFIG_WIRELESS_EXT
@@ -405,9 +410,9 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
 #endif
 
        if (ieee->iw_mode == IW_MODE_MONITOR) {
-               ieee80211_monitor_rx(ieee, skb, rx_stats);
                stats->rx_packets++;
                stats->rx_bytes += skb->len;
+               ieee80211_monitor_rx(ieee, skb, rx_stats);
                return 1;
        }
 
@@ -416,17 +421,16 @@ 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;
@@ -480,6 +484,11 @@ 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)
@@ -603,12 +612,12 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
                if (frag == 0) {
                        /* copy first fragment (including full headers) into
                         * beginning of the fragment cache skb */
-                       memcpy(skb_put(frag_skb, flen), skb->data, flen);
+                       skb_copy_from_linear_data(skb, skb_put(frag_skb, flen), flen);
                } else {
                        /* append frame payload to the end of the fragment
                         * cache skb */
-                       memcpy(skb_put(frag_skb, flen), skb->data + hdrlen,
-                              flen);
+                       skb_copy_from_linear_data_offset(skb, hdrlen,
+                                     skb_put(frag_skb, flen), flen);
                }
                dev_kfree_skb_any(skb);
                skb = NULL;
@@ -656,6 +665,51 @@ 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;
@@ -711,8 +765,9 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
                    IEEE80211_FCTL_TODS) && skb->len >= ETH_HLEN + ETH_ALEN) {
                /* Non-standard frame: get addr4 from its bogus location after
                 * the payload */
-               memcpy(skb->data + ETH_ALEN,
-                      skb->data + skb->len - ETH_ALEN, ETH_ALEN);
+               skb_copy_to_linear_data_offset(skb, ETH_ALEN,
+                                              skb->data + skb->len - ETH_ALEN,
+                                              ETH_ALEN);
                skb_trim(skb, skb->len - ETH_ALEN);
        }
 #endif
@@ -741,10 +796,11 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
 
        if (skb2 != NULL) {
                /* send to wireless media */
-               skb2->protocol = __constant_htons(ETH_P_802_3);
-               skb2->mac.raw = skb2->nh.raw = skb2->data;
-               /* skb2->nh.raw = skb2->data + ETH_HLEN; */
                skb2->dev = dev;
+               skb2->protocol = __constant_htons(ETH_P_802_3);
+               skb_reset_mac_header(skb2);
+               skb_reset_network_header(skb2);
+               /* skb2->network_header += ETH_HLEN; */
                dev_queue_xmit(skb2);
        }
 #endif
@@ -752,7 +808,6 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
        if (skb) {
                skb->protocol = eth_type_trans(skb, dev);
                memset(skb->cb, 0, sizeof(skb->cb));
-               skb->dev = dev;
                skb->ip_summed = CHECKSUM_NONE; /* 802.11 crc not sufficient */
                if (netif_rx(skb) == NET_RX_DROP) {
                        /* netif_rx always succeeds, but it might drop
@@ -780,6 +835,97 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
        return 0;
 }
 
+/* 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) {
+               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)
+               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);
+               dev_kfree_skb_irq(skb);
+               return;
+       case IEEE80211_FTYPE_DATA:
+               break;
+       case IEEE80211_FTYPE_CTL:
+               return;
+       default:
+               return;
+       }
+
+       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)
+               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
 
 static u8 qos_oui[QOS_OUI_LEN] = { 0x00, 0x50, 0xF2 };
@@ -994,7 +1140,10 @@ 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) {
@@ -1093,6 +1242,7 @@ 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;
@@ -1161,12 +1311,11 @@ 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;
 
@@ -1345,7 +1494,19 @@ static void update_network(struct ieee80211_network *dst,
        ieee80211_network_reset(dst);
        dst->ibss_dfs = src->ibss_dfs;
 
-       memcpy(&dst->stats, &src->stats, sizeof(struct ieee80211_rx_stats));
+       /* 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)
+               memcpy(&dst->stats, &src->stats,
+                      sizeof(struct ieee80211_rx_stats));
+       else
+               IEEE80211_DEBUG_SCAN("Network " MAC_FMT " info received "
+                       "off channel (%d vs. %d)\n", MAC_ARG(src->bssid),
+                       dst->channel, src->stats.received_channel);
+
        dst->capability = src->capability;
        memcpy(dst->rates, src->rates, src->rates_len);
        dst->rates_len = src->rates_len;
@@ -1515,10 +1676,10 @@ static void ieee80211_process_probe_response(struct ieee80211_device
 
        if (is_beacon(beacon->header.frame_ctl)) {
                if (ieee->handle_beacon != NULL)
-                       ieee->handle_beacon(dev, beacon, &network);
+                       ieee->handle_beacon(dev, beacon, target);
        } else {
                if (ieee->handle_probe_response != NULL)
-                       ieee->handle_probe_response(dev, beacon, &network);
+                       ieee->handle_probe_response(dev, beacon, target);
        }
 }
 
@@ -1606,8 +1767,8 @@ void ieee80211_rx_mgt(struct ieee80211_device *ieee,
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));
 
-               IEEE80211_WARNING("%s: IEEE80211_REASSOC_REQ received\n",
-                                 ieee->dev->name);
+               IEEE80211_DEBUG_MGMT("%s: IEEE80211_REASSOC_REQ received\n",
+                                    ieee->dev->name);
                if (ieee->handle_reassoc_request != NULL)
                        ieee->handle_reassoc_request(ieee->dev,
                                                    (struct ieee80211_reassoc_request *)
@@ -1619,8 +1780,8 @@ void ieee80211_rx_mgt(struct ieee80211_device *ieee,
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));
 
-               IEEE80211_WARNING("%s: IEEE80211_ASSOC_REQ received\n",
-                                 ieee->dev->name);
+               IEEE80211_DEBUG_MGMT("%s: IEEE80211_ASSOC_REQ received\n",
+                                    ieee->dev->name);
                if (ieee->handle_assoc_request != NULL)
                        ieee->handle_assoc_request(ieee->dev);
                break;
@@ -1636,13 +1797,14 @@ void ieee80211_rx_mgt(struct ieee80211_device *ieee,
                IEEE80211_DEBUG_MGMT("received UNKNOWN (%d)\n",
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));
-               IEEE80211_WARNING("%s: Unknown management packet: %d\n",
-                                 ieee->dev->name,
-                                 WLAN_FC_GET_STYPE(le16_to_cpu
-                                                   (header->frame_ctl)));
+               IEEE80211_DEBUG_MGMT("%s: Unknown management packet: %d\n",
+                                    ieee->dev->name,
+                                    WLAN_FC_GET_STYPE(le16_to_cpu
+                                                      (header->frame_ctl)));
                break;
        }
 }
 
+EXPORT_SYMBOL_GPL(ieee80211_rx_any);
 EXPORT_SYMBOL(ieee80211_rx_mgt);
 EXPORT_SYMBOL(ieee80211_rx);