diff options
Diffstat (limited to 'net/mac80211/rx.c')
| -rw-r--r-- | net/mac80211/rx.c | 1588 |
1 files changed, 1588 insertions, 0 deletions
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c new file mode 100644 index 00000000000..ece77766ea2 --- /dev/null +++ b/net/mac80211/rx.c @@ -0,0 +1,1588 @@ +/* + * Copyright 2002-2005, Instant802 Networks, Inc. + * Copyright 2005-2006, Devicescape Software, Inc. + * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> + * Copyright 2007 Johannes Berg <johannes@sipsolutions.net> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/skbuff.h> +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/rcupdate.h> +#include <net/mac80211.h> +#include <net/ieee80211_radiotap.h> + +#include "ieee80211_i.h" +#include "ieee80211_led.h" +#include "wep.h" +#include "wpa.h" +#include "tkip.h" +#include "wme.h" + +/* + * monitor mode reception + * + * This function cleans up the SKB, i.e. it removes all the stuff + * only useful for monitoring. + */ +static struct sk_buff *remove_monitor_info(struct ieee80211_local *local, + struct sk_buff *skb, + int rtap_len) +{ + skb_pull(skb, rtap_len); + + if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) { + if (likely(skb->len > FCS_LEN)) + skb_trim(skb, skb->len - FCS_LEN); + else { + /* driver bug */ + WARN_ON(1); + dev_kfree_skb(skb); + skb = NULL; + } + } + + return skb; +} + +static inline int should_drop_frame(struct ieee80211_rx_status *status, + struct sk_buff *skb, + int present_fcs_len, + int radiotap_len) +{ + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + + if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) + return 1; + if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len)) + return 1; + if ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FTYPE)) == + cpu_to_le16(IEEE80211_FTYPE_CTL)) + return 1; + return 0; +} + +/* + * This function copies a received frame to all monitor interfaces and + * returns a cleaned-up SKB that no longer includes the FCS nor the + * radiotap header the driver might have added. + */ +static struct sk_buff * +ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, + struct ieee80211_rx_status *status) +{ + struct ieee80211_sub_if_data *sdata; + struct ieee80211_rate *rate; + int needed_headroom = 0; + struct ieee80211_rtap_hdr { + struct ieee80211_radiotap_header hdr; + u8 flags; + u8 rate; + __le16 chan_freq; + __le16 chan_flags; + u8 antsignal; + u8 padding_for_rxflags; + __le16 rx_flags; + } __attribute__ ((packed)) *rthdr; + struct sk_buff *skb, *skb2; + struct net_device *prev_dev = NULL; + int present_fcs_len = 0; + int rtap_len = 0; + + /* + * First, we may need to make a copy of the skb because + * (1) we need to modify it for radiotap (if not present), and + * (2) the other RX handlers will modify the skb we got. + * + * We don't need to, of course, if we aren't going to return + * the SKB because it has a bad FCS/PLCP checksum. + */ + if (status->flag & RX_FLAG_RADIOTAP) + rtap_len = ieee80211_get_radiotap_len(origskb->data); + else + needed_headroom = sizeof(*rthdr); + + if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) + present_fcs_len = FCS_LEN; + + if (!local->monitors) { + if (should_drop_frame(status, origskb, present_fcs_len, + rtap_len)) { + dev_kfree_skb(origskb); + return NULL; + } + + return remove_monitor_info(local, origskb, rtap_len); + } + + if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) { + /* only need to expand headroom if necessary */ + skb = origskb; + origskb = NULL; + + /* + * This shouldn't trigger often because most devices have an + * RX header they pull before we get here, and that should + * be big enough for our radiotap information. We should + * probably export the length to drivers so that we can have + * them allocate enough headroom to start with. + */ + if (skb_headroom(skb) < needed_headroom && + pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) { + dev_kfree_skb(skb); + return NULL; + } + } else { + /* + * Need to make a copy and possibly remove radiotap header + * and FCS from the original. + */ + skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC); + + origskb = remove_monitor_info(local, origskb, rtap_len); + + if (!skb) + return origskb; + } + + /* if necessary, prepend radiotap information */ + if (!(status->flag & RX_FLAG_RADIOTAP)) { + rthdr = (void *) skb_push(skb, sizeof(*rthdr)); + memset(rthdr, 0, sizeof(*rthdr)); + rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); + rthdr->hdr.it_present = + cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | + (1 << IEEE80211_RADIOTAP_RATE) | + (1 << IEEE80211_RADIOTAP_CHANNEL) | + (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) | + (1 << IEEE80211_RADIOTAP_RX_FLAGS)); + rthdr->flags = local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS ? + IEEE80211_RADIOTAP_F_FCS : 0; + + /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */ + rthdr->rx_flags = 0; + if (status->flag & + (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) + rthdr->rx_flags |= + cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS); + + rate = ieee80211_get_rate(local, status->phymode, + status->rate); + if (rate) + rthdr->rate = rate->rate / 5; + + rthdr->chan_freq = cpu_to_le16(status->freq); + + if (status->phymode == MODE_IEEE80211A) + rthdr->chan_flags = + cpu_to_le16(IEEE80211_CHAN_OFDM | + IEEE80211_CHAN_5GHZ); + else + rthdr->chan_flags = + cpu_to_le16(IEEE80211_CHAN_DYN | + IEEE80211_CHAN_2GHZ); + + rthdr->antsignal = status->ssi; + } + + skb_set_mac_header(skb, 0); + skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->pkt_type = PACKET_OTHERHOST; + skb->protocol = htons(ETH_P_802_2); + + list_for_each_entry_rcu(sdata, &local->interfaces, list) { + if (!netif_running(sdata->dev)) + continue; + + if (sdata->type != IEEE80211_IF_TYPE_MNTR) + continue; + + if (prev_dev) { + skb2 = skb_clone(skb, GFP_ATOMIC); + if (skb2) { + skb2->dev = prev_dev; + netif_rx(skb2); + } + } + + prev_dev = sdata->dev; + sdata->dev->stats.rx_packets++; + sdata->dev->stats.rx_bytes += skb->len; + } + + if (prev_dev) { + skb->dev = prev_dev; + netif_rx(skb); + } else + dev_kfree_skb(skb); + + return origskb; +} + + +/* pre-rx handlers + * + * these don't have dev/sdata fields in the rx data + * The sta value should also not be used because it may + * be NULL even though a STA (in IBSS mode) will be added. + */ + +static ieee80211_txrx_result +ieee80211_rx_h_parse_qos(struct ieee80211_txrx_data *rx) +{ + u8 *data = rx->skb->data; + int tid; + + /* does the frame have a qos control field? */ + if (WLAN_FC_IS_QOS_DATA(rx->fc)) { + u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN; + /* frame has qos control */ + tid = qc[0] & QOS_CONTROL_TID_MASK; + } else { + if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) { + /* Separate TID for management frames */ + tid = NUM_RX_DATA_QUEUES - 1; + } else { + /* no qos control present */ + tid = 0; /* 802.1d - Best Effort */ + } + } + + I802_DEBUG_INC(rx->local->wme_rx_queue[tid]); + /* only a debug counter, sta might not be assigned properly yet */ + if (rx->sta) + I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]); + + rx->u.rx.queue = tid; + /* Set skb->priority to 1d tag if highest order bit of TID is not set. + * For now, set skb->priority to 0 for other cases. */ + rx->skb->priority = (tid > 7) ? 0 : tid; + + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_rx_h_load_stats(struct ieee80211_txrx_data *rx) +{ + struct ieee80211_local *local = rx->local; + struct sk_buff *skb = rx->skb; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + u32 load = 0, hdrtime; + struct ieee80211_rate *rate; + struct ieee80211_hw_mode *mode = local->hw.conf.mode; + int i; + + /* Estimate total channel use caused by this frame */ + + if (unlikely(mode->num_rates < 0)) + return TXRX_CONTINUE; + + rate = &mode->rates[0]; + for (i = 0; i < mode->num_rates; i++) { + if (mode->rates[i].val == rx->u.rx.status->rate) { + rate = &mode->rates[i]; + break; + } + } + + /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values, + * 1 usec = 1/8 * (1080 / 10) = 13.5 */ + + if (mode->mode == MODE_IEEE80211A || + (mode->mode == MODE_IEEE80211G && + rate->flags & IEEE80211_RATE_ERP)) + hdrtime = CHAN_UTIL_HDR_SHORT; + else + hdrtime = CHAN_UTIL_HDR_LONG; + + load = hdrtime; + if (!is_multicast_ether_addr(hdr->addr1)) + load += hdrtime; + + load += skb->len * rate->rate_inv; + + /* Divide channel_use by 8 to avoid wrapping around the counter */ + load >>= CHAN_UTIL_SHIFT; + local->channel_use_raw += load; + rx->u.rx.load = load; + + return TXRX_CONTINUE; +} + +ieee80211_rx_handler ieee80211_rx_pre_handlers[] = +{ + ieee80211_rx_h_parse_qos, + ieee80211_rx_h_load_stats, + NULL +}; + +/* rx handlers */ + +static ieee80211_txrx_result +ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx) +{ + if (rx->sta) + rx->sta->channel_use_raw += rx->u.rx.load; + rx->sdata->channel_use_raw += rx->u.rx.load; + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx) +{ + struct ieee80211_local *local = rx->local; + struct sk_buff *skb = rx->skb; + + if (unlikely(local->sta_scanning != 0)) { + ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status); + return TXRX_QUEUED; + } + + if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) { + /* scanning finished during invoking of handlers */ + I802_DEBUG_INC(local->rx_handlers_drop_passive_scan); + return TXRX_DROP; + } + + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_rx_h_check(struct ieee80211_txrx_data *rx) +{ + struct ieee80211_hdr *hdr; + hdr = (struct ieee80211_hdr *) rx->skb->data; + + /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */ + if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) { + if (unlikely(rx->fc & IEEE80211_FCTL_RETRY && + rx->sta->last_seq_ctrl[rx->u.rx.queue] == + hdr->seq_ctrl)) { + if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) { + rx->local->dot11FrameDuplicateCount++; + rx->sta->num_duplicates++; + } + return TXRX_DROP; + } else + rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl; + } + + if (unlikely(rx->skb->len < 16)) { + I802_DEBUG_INC(rx->local->rx_handlers_drop_short); + return TXRX_DROP; + } + + if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) + rx->skb->pkt_type = PACKET_OTHERHOST; + else if (compare_ether_addr(rx->dev->dev_addr, hdr->addr1) == 0) + rx->skb->pkt_type = PACKET_HOST; + else if (is_multicast_ether_addr(hdr->addr1)) { + if (is_broadcast_ether_addr(hdr->addr1)) + rx->skb->pkt_type = PACKET_BROADCAST; + else + rx->skb->pkt_type = PACKET_MULTICAST; + } else + rx->skb->pkt_type = PACKET_OTHERHOST; + + /* Drop disallowed frame classes based on STA auth/assoc state; + * IEEE 802.11, Chap 5.5. + * + * 80211.o does filtering only based on association state, i.e., it + * drops Class 3 frames from not associated stations. hostapd sends + * deauth/disassoc frames when needed. In addition, hostapd is + * responsible for filtering on both auth and assoc states. + */ + if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA || + ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL && + (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) && + rx->sdata->type != IEEE80211_IF_TYPE_IBSS && + (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) { + if ((!(rx->fc & IEEE80211_FCTL_FROMDS) && + !(rx->fc & IEEE80211_FCTL_TODS) && + (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) + || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) { + /* Drop IBSS frames and frames for other hosts + * silently. */ + return TXRX_DROP; + } + + return TXRX_DROP; + } + + return TXRX_CONTINUE; +} + + +static ieee80211_txrx_result +ieee80211_rx_h_decrypt(struct ieee80211_txrx_data *rx) +{ + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; + int keyidx; + int hdrlen; + ieee80211_txrx_result result = TXRX_DROP; + struct ieee80211_key *stakey = NULL; + + /* + * Key selection 101 + * + * There are three types of keys: + * - GTK (group keys) + * - PTK (pairwise keys) + * - STK (station-to-station pairwise keys) + * + * When selecting a key, we have to distinguish between multicast + * (including broadcast) and unicast frames, the latter can only + * use PTKs and STKs while the former always use GTKs. Unless, of + * course, actual WEP keys ("pre-RSNA") are used, then unicast + * frames can also use key indizes like GTKs. Hence, if we don't + * have a PTK/STK we check the key index for a WEP key. + * + * Note that in a regular BSS, multicast frames are sent by the + * AP only, associated stations unicast the frame to the AP first + * which then multicasts it on their behalf. + * + * There is also a slight problem in IBSS mode: GTKs are negotiated + * with each station, that is something we don't currently handle. + * The spec seems to expect that one negotiates the same key with + * every station but there's no such requirement; VLANs could be + * possible. + */ + + if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) + return TXRX_CONTINUE; + + /* + * No point in finding a key and decrypting if the frame is neither + * addressed to us nor a multicast frame. + */ + if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) + return TXRX_CONTINUE; + + if (rx->sta) + stakey = rcu_dereference(rx->sta->key); + + if (!is_multicast_ether_addr(hdr->addr1) && stakey) { + rx->key = stakey; + } else { + /* + * The device doesn't give us the IV so we won't be + * able to look up the key. That's ok though, we + * don't need to decrypt the frame, we just won't + * be able to keep statistics accurate. + * Except for key threshold notifications, should + * we somehow allow the driver to tell us which key + * the hardware used if this flag is set? + */ + if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) && + (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED)) + return TXRX_CONTINUE; + + hdrlen = ieee80211_get_hdrlen(rx->fc); + + if (rx->skb->len < 8 + hdrlen) + return TXRX_DROP; /* TODO: count this? */ + + /* + * no need to call ieee80211_wep_get_keyidx, + * it verifies a bunch of things we've done already + */ + keyidx = rx->skb->data[hdrlen + 3] >> 6; + + rx->key = rcu_dereference(rx->sdata->keys[keyidx]); + + /* + * RSNA-protected unicast frames should always be sent with + * pairwise or station-to-station keys, but for WEP we allow + * using a key index as well. + */ + if (rx->key && rx->key->conf.alg != ALG_WEP && + !is_multicast_ether_addr(hdr->addr1)) + rx->key = NULL; + } + + if (rx->key) { + rx->key->tx_rx_count++; + /* TODO: add threshold stuff again */ + } else { + if (net_ratelimit()) + printk(KERN_DEBUG "%s: RX protected frame," + " but have no key\n", rx->dev->name); + return TXRX_DROP; + } + + /* Check for weak IVs if possible */ + if (rx->sta && rx->key->conf.alg == ALG_WEP && + ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) && + (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) || + !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) && + ieee80211_wep_is_weak_iv(rx->skb, rx->key)) + rx->sta->wep_weak_iv_count++; + + switch (rx->key->conf.alg) { + case ALG_WEP: + result = ieee80211_crypto_wep_decrypt(rx); + break; + case ALG_TKIP: + result = ieee80211_crypto_tkip_decrypt(rx); + break; + case ALG_CCMP: + result = ieee80211_crypto_ccmp_decrypt(rx); + break; + } + + /* either the frame has been decrypted or will be dropped */ + rx->u.rx.status->flag |= RX_FLAG_DECRYPTED; + + return result; +} + +static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta) +{ + struct ieee80211_sub_if_data *sdata; + DECLARE_MAC_BUF(mac); + + sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev); + + if (sdata->bss) + atomic_inc(&sdata->bss->num_sta_ps); + sta->flags |= WLAN_STA_PS; + sta->pspoll = 0; +#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG + printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n", + dev->name, print_mac(mac, sta->addr), sta->aid); +#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ +} + +static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta) +{ + struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); + struct sk_buff *skb; + int sent = 0; + struct ieee80211_sub_if_data *sdata; + struct ieee80211_tx_packet_data *pkt_data; + DECLARE_MAC_BUF(mac); + + sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev); + if (sdata->bss) + atomic_dec(&sdata->bss->num_sta_ps); + sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM); + sta->pspoll = 0; + if (!skb_queue_empty(&sta->ps_tx_buf)) { + if (local->ops->set_tim) + local->ops->set_tim(local_to_hw(local), sta->aid, 0); + if (sdata->bss) + bss_tim_clear(local, sdata->bss, sta->aid); + } +#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG + printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n", + dev->name, print_mac(mac, sta->addr), sta->aid); +#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ + /* Send all buffered frames to the station */ + while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) { + pkt_data = (struct ieee80211_tx_packet_data *) skb->cb; + sent++; + pkt_data->flags |= IEEE80211_TXPD_REQUEUE; + dev_queue_xmit(skb); + } + while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) { + pkt_data = (struct ieee80211_tx_packet_data *) skb->cb; + local->total_ps_buffered--; + sent++; +#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG + printk(KERN_DEBUG "%s: STA %s aid %d send PS frame " + "since STA not sleeping anymore\n", dev->name, + print_mac(mac, sta->addr), sta->aid); +#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ + pkt_data->flags |= IEEE80211_TXPD_REQUEUE; + dev_queue_xmit(skb); + } + + return sent; +} + +static ieee80211_txrx_result +ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx) +{ + struct sta_info *sta = rx->sta; + struct net_device *dev = rx->dev; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; + + if (!sta) + return TXRX_CONTINUE; + + /* Update last_rx only for IBSS packets which are for the current + * BSSID to avoid keeping the current IBSS network alive in cases where + * other STAs are using different BSSID. */ + if (rx->sdata->type == IEEE80211_IF_TYPE_IBSS) { + u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len); + if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0) + sta->last_rx = jiffies; + } else + if (!is_multicast_ether_addr(hdr->addr1) || + rx->sdata->type == IEEE80211_IF_TYPE_STA) { + /* Update last_rx only for unicast frames in order to prevent + * the Probe Request frames (the only broadcast frames from a + * STA in infrastructure mode) from keeping a connection alive. + */ + sta->last_rx = jiffies; + } + + if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) + return TXRX_CONTINUE; + + sta->rx_fragments++; + sta->rx_bytes += rx->skb->len; + sta->last_rssi = rx->u.rx.status->ssi; + sta->last_signal = rx->u.rx.status->signal; + sta->last_noise = rx->u.rx.status->noise; + + if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) { + /* Change STA power saving mode only in the end of a frame + * exchange sequence */ + if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM)) + rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta); + else if (!(sta->flags & WLAN_STA_PS) && + (rx->fc & IEEE80211_FCTL_PM)) + ap_sta_ps_start(dev, sta); + } + + /* Drop data::nullfunc frames silently, since they are used only to + * control station power saving mode. */ + if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA && + (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) { + I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc); + /* Update counter and free packet here to avoid counting this + * as a dropped packed. */ + sta->rx_packets++; + dev_kfree_skb(rx->skb); + return TXRX_QUEUED; + } + + return TXRX_CONTINUE; +} /* ieee80211_rx_h_sta_process */ + +static inline struct ieee80211_fragment_entry * +ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata, + unsigned int frag, unsigned int seq, int rx_queue, + struct sk_buff **skb) +{ + struct ieee80211_fragment_entry *entry; + int idx; + + idx = sdata->fragment_next; + entry = &sdata->fragments[sdata->fragment_next++]; + if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX) + sdata->fragment_next = 0; + + if (!skb_queue_empty(&entry->skb_list)) { +#ifdef CONFIG_MAC80211_DEBUG + struct ieee80211_hdr *hdr = + (struct ieee80211_hdr *) entry->skb_list.next->data; + DECLARE_MAC_BUF(mac); + DECLARE_MAC_BUF(mac2); + printk(KERN_DEBUG "%s: RX reassembly removed oldest " + "fragment entry (idx=%d age=%lu seq=%d last_frag=%d " + "addr1=%s addr2=%s\n", + sdata->dev->name, idx, + jiffies - entry->first_frag_time, entry->seq, + entry->last_frag, print_mac(mac, hdr->addr1), + print_mac(mac2, hdr->addr2)); +#endif /* CONFIG_MAC80211_DEBUG */ + __skb_queue_purge(&entry->skb_list); + } + + __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */ + *skb = NULL; + entry->first_frag_time = jiffies; + entry->seq = seq; + entry->rx_queue = rx_queue; + entry->last_frag = frag; + entry->ccmp = 0; + entry->extra_len = 0; + + return entry; +} + +static inline struct ieee80211_fragment_entry * +ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata, + u16 fc, unsigned int frag, unsigned int seq, + int rx_queue, struct ieee80211_hdr *hdr) +{ + struct ieee80211_fragment_entry *entry; + int i, idx; + + idx = sdata->fragment_next; + for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) { + struct ieee80211_hdr *f_hdr; + u16 f_fc; + + idx--; + if (idx < 0) + idx = IEEE80211_FRAGMENT_MAX - 1; + + entry = &sdata->fragments[idx]; + if (skb_queue_empty(&entry->skb_list) || entry->seq != seq || + entry->rx_queue != rx_queue || + entry->last_frag + 1 != frag) + continue; + + f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data; + f_fc = le16_to_cpu(f_hdr->frame_control); + + if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) || + compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 || + compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0) + continue; + + if (entry->first_frag_time + 2 * HZ < jiffies) { + __skb_queue_purge(&entry->skb_list); + continue; + } + return entry; + } + + return NULL; +} + +static ieee80211_txrx_result +ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx) +{ + struct ieee80211_hdr *hdr; + u16 sc; + unsigned int frag, seq; + struct ieee80211_fragment_entry *entry; + struct sk_buff *skb; + DECLARE_MAC_BUF(mac); + + hdr = (struct ieee80211_hdr *) rx->skb->data; + sc = le16_to_cpu(hdr->seq_ctrl); + frag = sc & IEEE80211_SCTL_FRAG; + + if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) || + (rx->skb)->len < 24 || + is_multicast_ether_addr(hdr->addr1))) { + /* not fragmented */ + goto out; + } + I802_DEBUG_INC(rx->local->rx_handlers_fragments); + + seq = (sc & IEEE80211_SCTL_SEQ) >> 4; + + if (frag == 0) { + /* This is the first fragment of a new frame. */ + entry = ieee80211_reassemble_add(rx->sdata, frag, seq, + rx->u.rx.queue, &(rx->skb)); + if (rx->key && rx->key->conf.alg == ALG_CCMP && + (rx->fc & IEEE80211_FCTL_PROTECTED)) { + /* Store CCMP PN so that we can verify that the next + * fragment has a sequential PN value. */ + entry->ccmp = 1; + memcpy(entry->last_pn, + rx->key->u.ccmp.rx_pn[rx->u.rx.queue], + CCMP_PN_LEN); + } + return TXRX_QUEUED; + } + + /* This is a fragment for a frame that should already be pending in + * fragment cache. Add this fragment to the end of the pending entry. + */ + entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq, + rx->u.rx.queue, hdr); + if (!entry) { + I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); + return TXRX_DROP; + } + + /* Verify that MPDUs within one MSDU have sequential PN values. + * (IEEE 802.11i, 8.3.3.4.5) */ + if (entry->ccmp) { + int i; + u8 pn[CCMP_PN_LEN], *rpn; + if (!rx->key || rx->key->conf.alg != ALG_CCMP) + return TXRX_DROP; + memcpy(pn, entry->last_pn, CCMP_PN_LEN); + for (i = CCMP_PN_LEN - 1; i >= 0; i--) { + pn[i]++; + if (pn[i]) + break; + } + rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue]; + if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) { + if (net_ratelimit()) + printk(KERN_DEBUG "%s: defrag: CCMP PN not " + "sequential A2=%s" + " PN=%02x%02x%02x%02x%02x%02x " + "(expected %02x%02x%02x%02x%02x%02x)\n", + rx->dev->name, print_mac(mac, hdr->addr2), + rpn[0], rpn[1], rpn[2], rpn[3], rpn[4], + rpn[5], pn[0], pn[1], pn[2], pn[3], + pn[4], pn[5]); + return TXRX_DROP; + } + memcpy(entry->last_pn, pn, CCMP_PN_LEN); + } + + skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc)); + __skb_queue_tail(&entry->skb_list, rx->skb); + entry->last_frag = frag; + entry->extra_len += rx->skb->len; + if (rx->fc & IEEE80211_FCTL_MOREFRAGS) { + rx->skb = NULL; + return TXRX_QUEUED; + } + + rx->skb = __skb_dequeue(&entry->skb_list); + if (skb_tailroom(rx->skb) < entry->extra_len) { + I802_DEBUG_INC(rx->local->rx_expand_skb_head2); + if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len, + GFP_ATOMIC))) { + I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); + __skb_queue_purge(&entry->skb_list); + return TXRX_DROP; + } + } + while ((skb = __skb_dequeue(&entry->skb_list))) { + memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len); + dev_kfree_skb(skb); + } + + /* Complete frame has been reassembled - process it now */ + rx->flags |= IEEE80211_TXRXD_FRAGMENTED; + + out: + if (rx->sta) + rx->sta->rx_packets++; + if (is_multicast_ether_addr(hdr->addr1)) + rx->local->dot11MulticastReceivedFrameCount++; + else + ieee80211_led_rx(rx->local); + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx) +{ + struct sk_buff *skb; + int no_pending_pkts; + DECLARE_MAC_BUF(mac); + + if (likely(!rx->sta || + (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL || + (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL || + !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))) + return TXRX_CONTINUE; + + skb = skb_dequeue(&rx->sta->tx_filtered); + if (!skb) { + skb = skb_dequeue(&rx->sta->ps_tx_buf); + if (skb) + rx->local->total_ps_buffered--; + } + no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) && + skb_queue_empty(&rx->sta->ps_tx_buf); + + if (skb) { + struct ieee80211_hdr *hdr = + (struct ieee80211_hdr *) skb->data; + + /* tell TX path to send one frame even though the STA may + * still remain is PS mode after this frame exchange */ + rx->sta->pspoll = 1; + +#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG + printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n", + print_mac(mac, rx->sta->addr), rx->sta->aid, + skb_queue_len(&rx->sta->ps_tx_buf)); +#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ + + /* Use MoreData flag to indicate whether there are more + * buffered frames for this STA */ + if (no_pending_pkts) { + hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA); + rx->sta->flags &= ~WLAN_STA_TIM; + } else + hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA); + + dev_queue_xmit(skb); + + if (no_pending_pkts) { + if (rx->local->ops->set_tim) + rx->local->ops->set_tim(local_to_hw(rx->local), + rx->sta->aid, 0); + if (rx->sdata->bss) + bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid); + } +#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG + } else if (!rx->u.rx.sent_ps_buffered) { + printk(KERN_DEBUG "%s: STA %s sent PS Poll even " + "though there is no buffered frames for it\n", + rx->dev->name, print_mac(mac, rx->sta->addr)); +#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ + + } + + /* Free PS Poll skb here instead of returning TXRX_DROP that would + * count as an dropped frame. */ + dev_kfree_skb(rx->skb); + + return TXRX_QUEUED; +} + +static ieee80211_txrx_result +ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx) +{ + u16 fc = rx->fc; + u8 *data = rx->skb->data; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data; + + if (!WLAN_FC_IS_QOS_DATA(fc)) + return TXRX_CONTINUE; + + /* remove the qos control field, update frame type and meta-data */ + memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2); + hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2); + /* change frame type to non QOS */ + rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA; + hdr->frame_control = cpu_to_le16(fc); + + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_rx_h_802_1x_pae(struct ieee80211_txrx_data *rx) +{ + if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb) && + rx->sdata->type != IEEE80211_IF_TYPE_STA && + (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) + return TXRX_CONTINUE; + + if (unlikely(rx->sdata->ieee802_1x && + (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA && + (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC && + (!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)) && + !ieee80211_is_eapol(rx->skb))) { +#ifdef CONFIG_MAC80211_DEBUG + struct ieee80211_hdr *hdr = + (struct ieee80211_hdr *) rx->skb->data; + DECLARE_MAC_BUF(mac); + printk(KERN_DEBUG "%s: dropped frame from %s" + " (unauthorized port)\n", rx->dev->name, + print_mac(mac, hdr->addr2)); +#endif /* CONFIG_MAC80211_DEBUG */ + return TXRX_DROP; + } + + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_rx_h_drop_unencrypted(struct ieee80211_txrx_data *rx) +{ + /* + * Pass through unencrypted frames if the hardware has + * decrypted them already. + */ + if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED) + return TXRX_CONTINUE; + + /* Drop unencrypted frames if key is set. */ + if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) && + (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA && + (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC && + rx->sdata->drop_unencrypted && + (rx->sdata->eapol == 0 || !ieee80211_is_eapol(rx->skb)))) { + if (net_ratelimit()) + printk(KERN_DEBUG "%s: RX non-WEP frame, but expected " + "encryption\n", rx->dev->name); + return TXRX_DROP; + } + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_rx_h_data(struct ieee80211_txrx_data *rx) +{ + struct net_device *dev = rx->dev; + struct ieee80211_local *local = rx->local; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; + u16 fc, hdrlen, ethertype; + u8 *payload; + u8 dst[ETH_ALEN]; + u8 src[ETH_ALEN]; + struct sk_buff *skb = rx->skb, *skb2; + struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); + DECLARE_MAC_BUF(mac); + DECLARE_MAC_BUF(mac2); + DECLARE_MAC_BUF(mac3); + DECLARE_MAC_BUF(mac4); + + fc = rx->fc; + if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)) + return TXRX_CONTINUE; + + if (unlikely(!WLAN_FC_DATA_PRESENT(fc))) + return TXRX_DROP; + + hdrlen = ieee80211_get_hdrlen(fc); + + /* convert IEEE 802.11 header + possible LLC headers into Ethernet + * header + * IEEE 802.11 address fields: + * ToDS FromDS Addr1 Addr2 Addr3 Addr4 + * 0 0 DA SA BSSID n/a + * 0 1 DA BSSID SA n/a + * 1 0 BSSID SA DA n/a + * 1 1 RA TA DA SA + */ + + switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) { + case IEEE80211_FCTL_TODS: + /* BSSID SA DA */ + memcpy(dst, hdr->addr3, ETH_ALEN); + memcpy(src, hdr->addr2, ETH_ALEN); + + if (unlikely(sdata->type != IEEE80211_IF_TYPE_AP && + sdata->type != IEEE80211_IF_TYPE_VLAN)) { + if (net_ratelimit()) + printk(KERN_DEBUG "%s: dropped ToDS frame " + "(BSSID=%s SA=%s DA=%s)\n", + dev->name, + print_mac(mac, hdr->addr1), + print_mac(mac2, hdr->addr2), + print_mac(mac3, hdr->addr3)); + return TXRX_DROP; + } + break; + case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS): + /* RA TA DA SA */ + memcpy(dst, hdr->addr3, ETH_ALEN); + memcpy(src, hdr->addr4, ETH_ALEN); + + if (unlikely(sdata->type != IEEE80211_IF_TYPE_WDS)) { + if (net_ratelimit()) + printk(KERN_DEBUG "%s: dropped FromDS&ToDS " + "frame (RA=%s TA=%s DA=%s SA=%s)\n", + rx->dev->name, + print_mac(mac, hdr->addr1), + print_mac(mac2, hdr->addr2), + print_mac(mac3, hdr->addr3), + print_mac(mac4, hdr->addr4)); + return TXRX_DROP; + } + break; + case IEEE80211_FCTL_FROMDS: + /* DA BSSID SA */ + memcpy(dst, hdr->addr1, ETH_ALEN); + memcpy(src, hdr->addr3, ETH_ALEN); + + if (sdata->type != IEEE80211_IF_TYPE_STA || + (is_multicast_ether_addr(dst) && + !compare_ether_addr(src, dev->dev_addr))) + return TXRX_DROP; + break; + case 0: + /* DA SA BSSID */ + memcpy(dst, hdr->addr1, ETH_ALEN); + memcpy(src, hdr->addr2, ETH_ALEN); + + if (sdata->type != IEEE80211_IF_TYPE_IBSS) { + if (net_ratelimit()) { + printk(KERN_DEBUG "%s: dropped IBSS frame " + "(DA=%s SA=%s BSSID=%s)\n", + dev->name, + print_mac(mac, hdr->addr1), + print_mac(mac2, hdr->addr2), + print_mac(mac3, hdr->addr3)); + } + return TXRX_DROP; + } + break; + } + + payload = skb->data + hdrlen; + + if (unlikely(skb->len - hdrlen < 8)) { + if (net_ratelimit()) { + printk(KERN_DEBUG "%s: RX too short data frame " + "payload\n", dev->name); + } + return TXRX_DROP; + } + + ethertype = (payload[6] << 8) | payload[7]; + + if (likely((compare_ether_addr(payload, rfc1042_header) == 0 && + ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) || + compare_ether_addr(payload, bridge_tunnel_header) == 0)) { + /* remove RFC1042 or Bridge-Tunnel encapsulation and + * replace EtherType */ + skb_pull(skb, hdrlen + 6); + memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN); + memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN); + } else { + struct ethhdr *ehdr; + __be16 len; + skb_pull(skb, hdrlen); + len = htons(skb->len); + ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr)); + memcpy(ehdr->h_dest, dst, ETH_ALEN); + memcpy(ehdr->h_source, src, ETH_ALEN); + ehdr->h_proto = len; + } + skb->dev = dev; + + skb2 = NULL; + + dev->stats.rx_packets++; + dev->stats.rx_bytes += skb->len; + + if (local->bridge_packets && (sdata->type == IEEE80211_IF_TYPE_AP + || sdata->type == IEEE80211_IF_TYPE_VLAN) && + (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) { + if (is_multicast_ether_addr(skb->data)) { + /* send multicast frames both to higher layers in + * local net stack and back to the wireless media */ + skb2 = skb_copy(skb, GFP_ATOMIC); + if (!skb2 && net_ratelimit()) + printk(KERN_DEBUG "%s: failed to clone " + "multicast frame\n", dev->name); + } else { + struct sta_info *dsta; + dsta = sta_info_get(local, skb->data); + if (dsta && !dsta->dev) { + if (net_ratelimit()) + printk(KERN_DEBUG "Station with null " + "dev structure!\n"); + } else if (dsta && dsta->dev == dev) { + /* Destination station is associated to this + * AP, so send the frame directly to it and + * do not pass the frame to local net stack. + */ + skb2 = skb; + skb = NULL; + } + if (dsta) + sta_info_put(dsta); + } + } + + if (skb) { + /* deliver to local stack */ + skb->protocol = eth_type_trans(skb, dev); + memset(skb->cb, 0, sizeof(skb->cb)); + netif_rx(skb); + } + + if (skb2) { + /* send to wireless media */ + skb2->protocol = __constant_htons(ETH_P_802_3); + skb_set_network_header(skb2, 0); + skb_set_mac_header(skb2, 0); + dev_queue_xmit(skb2); + } + + return TXRX_QUEUED; +} + +static ieee80211_txrx_result +ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx) +{ + struct ieee80211_sub_if_data *sdata; + + if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) + return TXRX_DROP; + + sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); + if ((sdata->type == IEEE80211_IF_TYPE_STA || + sdata->type == IEEE80211_IF_TYPE_IBSS) && + !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME)) + ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status); + else + return TXRX_DROP; + + return TXRX_QUEUED; +} + +static inline ieee80211_txrx_result __ieee80211_invoke_rx_handlers( + struct ieee80211_local *local, + ieee80211_rx_handler *handlers, + struct ieee80211_txrx_data *rx, + struct sta_info *sta) +{ + ieee80211_rx_handler *handler; + ieee80211_txrx_result res = TXRX_DROP; + + for (handler = handlers; *handler != NULL; handler++) { + res = (*handler)(rx); + + switch (res) { + case TXRX_CONTINUE: + continue; + case TXRX_DROP: + I802_DEBUG_INC(local->rx_handlers_drop); + if (sta) + sta->rx_dropped++; + break; + case TXRX_QUEUED: + I802_DEBUG_INC(local->rx_handlers_queued); + break; + } + break; + } + + if (res == TXRX_DROP) + dev_kfree_skb(rx->skb); + return res; +} + +static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local, + ieee80211_rx_handler *handlers, + struct ieee80211_txrx_data *rx, + struct sta_info *sta) +{ + if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) == + TXRX_CONTINUE) + dev_kfree_skb(rx->skb); +} + +static void ieee80211_rx_michael_mic_report(struct net_device *dev, + struct ieee80211_hdr *hdr, + struct sta_info *sta, + struct ieee80211_txrx_data *rx) +{ + int keyidx, hdrlen; + DECLARE_MAC_BUF(mac); + DECLARE_MAC_BUF(mac2); + + hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb); + if (rx->skb->len >= hdrlen + 4) + keyidx = rx->skb->data[hdrlen + 3] >> 6; + else + keyidx = -1; + + if (net_ratelimit()) + printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC " + "failure from %s to %s keyidx=%d\n", + dev->name, print_mac(mac, hdr->addr2), + print_mac(mac2, hdr->addr1), keyidx); + + if (!sta) { + /* + * Some hardware seem to generate incorrect Michael MIC + * reports; ignore them to avoid triggering countermeasures. + */ + if (net_ratelimit()) + printk(KERN_DEBUG "%s: ignored spurious Michael MIC " + "error for unknown address %s\n", + dev->name, print_mac(mac, hdr->addr2)); + goto ignore; + } + + if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) { + if (net_ratelimit()) + printk(KERN_DEBUG "%s: ignored spurious Michael MIC " + "error for a frame with no PROTECTED flag (src " + "%s)\n", dev->name, print_mac(mac, hdr->addr2)); + goto ignore; + } + + if (rx->sdata->type == IEEE80211_IF_TYPE_AP && keyidx) { + /* + * APs with pairwise keys should never receive Michael MIC + * errors for non-zero keyidx because these are reserved for + * group keys and only the AP is sending real multicast + * frames in the BSS. + */ + if (net_ratelimit()) + printk(KERN_DEBUG "%s: ignored Michael MIC error for " + "a frame with non-zero keyidx (%d)" + " (src %s)\n", dev->name, keyidx, + print_mac(mac, hdr->addr2)); + goto ignore; + } + + if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA && + ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT || + (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) { + if (net_ratelimit()) + printk(KERN_DEBUG "%s: ignored spurious Michael MIC " + "error for a frame that cannot be encrypted " + "(fc=0x%04x) (src %s)\n", + dev->name, rx->fc, print_mac(mac, hdr->addr2)); + goto ignore; + } + + mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr); + ignore: + dev_kfree_skb(rx->skb); + rx->skb = NULL; +} + +ieee80211_rx_handler ieee80211_rx_handlers[] = +{ + ieee80211_rx_h_if_stats, + ieee80211_rx_h_passive_scan, + ieee80211_rx_h_check, + ieee80211_rx_h_decrypt, + ieee80211_rx_h_sta_process, + ieee80211_rx_h_defragment, + ieee80211_rx_h_ps_poll, + ieee80211_rx_h_michael_mic_verify, + /* this must be after decryption - so header is counted in MPDU mic + * must be before pae and data, so QOS_DATA format frames + * are not passed to user space by these functions + */ + ieee80211_rx_h_remove_qos_control, + ieee80211_rx_h_802_1x_pae, + ieee80211_rx_h_drop_unencrypted, + ieee80211_rx_h_data, + ieee80211_rx_h_mgmt, + NULL +}; + +/* main receive path */ + +static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata, + u8 *bssid, struct ieee80211_txrx_data *rx, + struct ieee80211_hdr *hdr) +{ + int multicast = is_multicast_ether_addr(hdr->addr1); + + switch (sdata->type) { + case IEEE80211_IF_TYPE_STA: + if (!bssid) + return 0; + if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) { + if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) + return 0; + rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH; + } else if (!multicast && + compare_ether_addr(sdata->dev->dev_addr, + hdr->addr1) != 0) { + if (!(sdata->dev->flags & IFF_PROMISC)) + return 0; + rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH; + } + break; + case IEEE80211_IF_TYPE_IBSS: + if (!bssid) + return 0; + if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) { + if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) + return 0; + rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH; + } else if (!multicast && + compare_ether_addr(sdata->dev->dev_addr, + hdr->addr1) != 0) { + if (!(sdata->dev->flags & IFF_PROMISC)) + return 0; + rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH; + } else if (!rx->sta) + rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb, + bssid, hdr->addr2); + break; + case IEEE80211_IF_TYPE_VLAN: + case IEEE80211_IF_TYPE_AP: + if (!bssid) { + if (compare_ether_addr(sdata->dev->dev_addr, + hdr->addr1)) + return 0; + } else if (!ieee80211_bssid_match(bssid, + sdata->dev->dev_addr)) { + if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) + return 0; + rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH; + } + if (sdata->dev == sdata->local->mdev && + !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) + /* do not receive anything via + * master device when not scanning */ + return 0; + break; + case IEEE80211_IF_TYPE_WDS: + if (bssid || + (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA) + return 0; + if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) + return 0; + break; + case IEEE80211_IF_TYPE_MNTR: + /* take everything */ + break; + case IEEE80211_IF_TYPE_INVALID: + /* should never get here */ + WARN_ON(1); + break; + } + + return 1; +} + +/* + * This is the receive path handler. It is called by a low level driver when an + * 802.11 MPDU is received from the hardware. + */ +void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, + struct ieee80211_rx_status *status) +{ + struct ieee80211_local *local = hw_to_local(hw); + struct ieee80211_sub_if_data *sdata; + struct sta_info *sta; + struct ieee80211_hdr *hdr; + struct ieee80211_txrx_data rx; + u16 type; + int prepres; + struct ieee80211_sub_if_data *prev = NULL; + struct sk_buff *skb_new; + u8 *bssid; + + /* + * key references and virtual interfaces are protected using RCU + * and this requires that we are in a read-side RCU section during + * receive processing + */ + rcu_read_lock(); + + /* + * Frames with failed FCS/PLCP checksum are not returned, + * all other frames are returned without radiotap header + * if it was previously present. + * Also, frames with less than 16 bytes are dropped. + */ + skb = ieee80211_rx_monitor(local, skb, status); + if (!skb) { + rcu_read_unlock(); + return; + } + + hdr = (struct ieee80211_hdr *) skb->data; + memset(&rx, 0, sizeof(rx)); + rx.skb = skb; + rx.local = local; + + rx.u.rx.status = status; + rx.fc = le16_to_cpu(hdr->frame_control); + type = rx.fc & IEEE80211_FCTL_FTYPE; + + if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT) + local->dot11ReceivedFragmentCount++; + + sta = rx.sta = sta_info_get(local, hdr->addr2); + if (sta) { + rx.dev = rx.sta->dev; + rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev); + } + + if ((status->flag & RX_FLAG_MMIC_ERROR)) { + ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx); + goto end; + } + + if (unlikely(local->sta_scanning)) + rx.flags |= IEEE80211_TXRXD_RXIN_SCAN; + + if (__ieee80211_invoke_rx_handlers(local, local->rx_pre_handlers, &rx, + sta) != TXRX_CONTINUE) + goto end; + skb = rx.skb; + + if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) && + !atomic_read(&local->iff_promiscs) && + !is_multicast_ether_addr(hdr->addr1)) { + rx.flags |= IEEE80211_TXRXD_RXRA_MATCH; + ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx, + rx.sta); + sta_info_put(sta); + rcu_read_unlock(); + return; + } + + bssid = ieee80211_get_bssid(hdr, skb->len); + + list_for_each_entry_rcu(sdata, &local->interfaces, list) { + if (!netif_running(sdata->dev)) + continue; + + if (sdata->type == IEEE80211_IF_TYPE_MNTR) + continue; + + rx.flags |= IEEE80211_TXRXD_RXRA_MATCH; + prepres = prepare_for_handlers(sdata, bssid, &rx, hdr); + /* prepare_for_handlers can change sta */ + sta = rx.sta; + + if (!prepres) + continue; + + /* + * frame is destined for this interface, but if it's not + * also for the previous one we handle that after the + * loop to avoid copying the SKB once too much + */ + + if (!prev) { + prev = sdata; + continue; + } + + /* + * frame was destined for the previous interface + * so invoke RX handlers for it + */ + + skb_new = skb_copy(skb, GFP_ATOMIC); + if (!skb_new) { + if (net_ratelimit()) + printk(KERN_DEBUG "%s: failed to copy " + "multicast frame for %s", + wiphy_name(local->hw.wiphy), + prev->dev->name); + continue; + } + rx.skb = skb_new; + rx.dev = prev->dev; + rx.sdata = prev; + ieee80211_invoke_rx_handlers(local, local->rx_handlers, + &rx, sta); + prev = sdata; + } + if (prev) { + rx.skb = skb; + rx.dev = prev->dev; + rx.sdata = prev; + ieee80211_invoke_rx_handlers(local, local->rx_handlers, + &rx, sta); + } else + dev_kfree_skb(skb); + + end: + rcu_read_unlock(); + + if (sta) + sta_info_put(sta); +} +EXPORT_SYMBOL(__ieee80211_rx); + +/* This is a version of the rx handler that can be called from hard irq + * context. Post the skb on the queue and schedule the tasklet */ +void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb, + struct ieee80211_rx_status *status) +{ + struct ieee80211_local *local = hw_to_local(hw); + + BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); + + skb->dev = local->mdev; + /* copy status into skb->cb for use by tasklet */ + memcpy(skb->cb, status, sizeof(*status)); + skb->pkt_type = IEEE80211_RX_MSG; + skb_queue_tail(&local->skb_queue, skb); + tasklet_schedule(&local->tasklet); +} +EXPORT_SYMBOL(ieee80211_rx_irqsafe); |