/* * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2005-2006, Devicescape Software, Inc. * Copyright 2006-2007 Jiri Benc * Copyright 2007-2010 Johannes Berg * * 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 #include #include #include #include #include #include #include #include "ieee80211_i.h" #include "driver-ops.h" #include "led.h" #include "mesh.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) { 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 sk_buff *skb, int present_fcs_len) { struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 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)) return 1; if (ieee80211_is_ctl(hdr->frame_control) && !ieee80211_is_pspoll(hdr->frame_control) && !ieee80211_is_back_req(hdr->frame_control)) return 1; return 0; } static int ieee80211_rx_radiotap_len(struct ieee80211_local *local, struct ieee80211_rx_status *status) { int len; /* always present fields */ len = sizeof(struct ieee80211_radiotap_header) + 9; if (status->flag & RX_FLAG_TSFT) len += 8; if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) len += 1; if (local->hw.flags & IEEE80211_HW_NOISE_DBM) len += 1; if (len & 1) /* padding for RX_FLAGS if necessary */ len++; return len; } /* * ieee80211_add_rx_radiotap_header - add radiotap header * * add a radiotap header containing all the fields which the hardware provided. */ static void ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, struct sk_buff *skb, struct ieee80211_rate *rate, int rtap_len) { struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); struct ieee80211_radiotap_header *rthdr; unsigned char *pos; u16 rx_flags = 0; rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len); memset(rthdr, 0, rtap_len); /* radiotap header, set always present flags */ rthdr->it_present = cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | (1 << IEEE80211_RADIOTAP_CHANNEL) | (1 << IEEE80211_RADIOTAP_ANTENNA) | (1 << IEEE80211_RADIOTAP_RX_FLAGS)); rthdr->it_len = cpu_to_le16(rtap_len); pos = (unsigned char *)(rthdr+1); /* the order of the following fields is important */ /* IEEE80211_RADIOTAP_TSFT */ if (status->flag & RX_FLAG_TSFT) { put_unaligned_le64(status->mactime, pos); rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT); pos += 8; } /* IEEE80211_RADIOTAP_FLAGS */ if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) *pos |= IEEE80211_RADIOTAP_F_FCS; if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) *pos |= IEEE80211_RADIOTAP_F_BADFCS; if (status->flag & RX_FLAG_SHORTPRE) *pos |= IEEE80211_RADIOTAP_F_SHORTPRE; pos++; /* IEEE80211_RADIOTAP_RATE */ if (status->flag & RX_FLAG_HT) { /* * TODO: add following information into radiotap header once * suitable fields are defined for it: * - MCS index (status->rate_idx) * - HT40 (status->flag & RX_FLAG_40MHZ) * - short-GI (status->flag & RX_FLAG_SHORT_GI) */ *pos = 0; } else { rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); *pos = rate->bitrate / 5; } pos++; /* IEEE80211_RADIOTAP_CHANNEL */ put_unaligned_le16(status->freq, pos); pos += 2; if (status->band == IEEE80211_BAND_5GHZ) put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ, pos); else if (status->flag & RX_FLAG_HT) put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ, pos); else if (rate->flags & IEEE80211_RATE_ERP_G) put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ, pos); else put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ, pos); pos += 2; /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */ if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) { *pos = status->signal; rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL); pos++; } /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */ /* IEEE80211_RADIOTAP_ANTENNA */ *pos = status->antenna; pos++; /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */ /* IEEE80211_RADIOTAP_RX_FLAGS */ /* ensure 2 byte alignment for the 2 byte field as required */ if ((pos - (u8 *)rthdr) & 1) pos++; if (status->flag & RX_FLAG_FAILED_PLCP_CRC) rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP; put_unaligned_le16(rx_flags, pos); pos += 2; } /* * 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_rate *rate) { struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb); struct ieee80211_sub_if_data *sdata; int needed_headroom = 0; struct sk_buff *skb, *skb2; struct net_device *prev_dev = NULL; int present_fcs_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. */ /* room for the radiotap header based on driver features */ needed_headroom = ieee80211_rx_radiotap_len(local, status); if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) present_fcs_len = FCS_LEN; if (!local->monitors) { if (should_drop_frame(origskb, present_fcs_len)) { dev_kfree_skb(origskb); return NULL; } return remove_monitor_info(local, origskb); } if (should_drop_frame(origskb, present_fcs_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, needed_headroom, 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); if (!skb) return origskb; } /* prepend radiotap information */ ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom); skb_reset_mac_header(skb); 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 (sdata->vif.type != NL80211_IFTYPE_MONITOR) continue; if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) continue; if (!ieee80211_sdata_running(sdata)) 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; } static void ieee80211_parse_qos(struct ieee80211_rx_data *rx) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; int tid; /* does the frame have a qos control field? */ if (ieee80211_is_data_qos(hdr->frame_control)) { u8 *qc = ieee80211_get_qos_ctl(hdr); /* frame has qos control */ tid = *qc & IEEE80211_QOS_CTL_TID_MASK; if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT) rx->flags |= IEEE80211_RX_AMSDU; else rx->flags &= ~IEEE80211_RX_AMSDU; } else { /* * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"): * * Sequence numbers for management frames, QoS data * frames with a broadcast/multicast address in the * Address 1 field, and all non-QoS data frames sent * by QoS STAs are assigned using an additional single * modulo-4096 counter, [...] * * We also use that counter for non-QoS STAs. */ tid = NUM_RX_DATA_QUEUES - 1; } 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; } /** * DOC: Packet alignment * * Drivers always need to pass packets that are aligned to two-byte boundaries * to the stack. * * Additionally, should, if possible, align the payload data in a way that * guarantees that the contained IP header is aligned to a four-byte * boundary. In the case of regular frames, this simply means aligning the * payload to a four-byte boundary (because either the IP header is directly * contained, or IV/RFC1042 headers that have a length divisible by four are * in front of it). If the payload data is not properly aligned and the * architecture doesn't support efficient unaligned operations, mac80211 * will align the data. * * With A-MSDU frames, however, the payload data address must yield two modulo * four because there are 14-byte 802.3 headers within the A-MSDU frames that * push the IP header further back to a multiple of four again. Thankfully, the * specs were sane enough this time around to require padding each A-MSDU * subframe to a length that is a multiple of four. * * Padding like Atheros hardware adds which is inbetween the 802.11 header and * the payload is not supported, the driver is required to move the 802.11 * header to be directly in front of the payload in that case. */ static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx) { #ifdef CONFIG_MAC80211_VERBOSE_DEBUG WARN_ONCE((unsigned long)rx->skb->data & 1, "unaligned packet at 0x%p\n", rx->skb->data); #endif } /* rx handlers */ static ieee80211_rx_result debug_noinline ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx) { struct ieee80211_local *local = rx->local; struct sk_buff *skb = rx->skb; if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning))) return ieee80211_scan_rx(rx->sdata, skb); if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) && (rx->flags & IEEE80211_RX_IN_SCAN))) { /* drop all the other packets during a software scan anyway */ if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED) dev_kfree_skb(skb); return RX_QUEUED; } if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) { /* scanning finished during invoking of handlers */ I802_DEBUG_INC(local->rx_handlers_drop_passive_scan); return RX_DROP_UNUSABLE; } return RX_CONTINUE; } static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1)) return 0; return ieee80211_is_robust_mgmt_frame(hdr); } static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1)) return 0; return ieee80211_is_robust_mgmt_frame(hdr); } /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */ static int ieee80211_get_mmie_keyidx(struct sk_buff *skb) { struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data; struct ieee80211_mmie *mmie; if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da)) return -1; if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr)) return -1; /* not a robust management frame */ mmie = (struct ieee80211_mmie *) (skb->data + skb->len - sizeof(*mmie)); if (mmie->element_id != WLAN_EID_MMIE || mmie->length != sizeof(*mmie) - 2) return -1; return le16_to_cpu(mmie->key_id); } static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control); char *dev_addr = rx->sdata->vif.addr; if (ieee80211_is_data(hdr->frame_control)) { if (is_multicast_ether_addr(hdr->addr1)) { if (ieee80211_has_tods(hdr->frame_control) || !ieee80211_has_fromds(hdr->frame_control)) return RX_DROP_MONITOR; if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0) return RX_DROP_MONITOR; } else { if (!ieee80211_has_a4(hdr->frame_control)) return RX_DROP_MONITOR; if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0) return RX_DROP_MONITOR; } } /* If there is not an established peer link and this is not a peer link * establisment frame, beacon or probe, drop the frame. */ if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) { struct ieee80211_mgmt *mgmt; if (!ieee80211_is_mgmt(hdr->frame_control)) return RX_DROP_MONITOR; if (ieee80211_is_action(hdr->frame_control)) { mgmt = (struct ieee80211_mgmt *)hdr; if (mgmt->u.action.category != MESH_PLINK_CATEGORY) return RX_DROP_MONITOR; return RX_CONTINUE; } if (ieee80211_is_probe_req(hdr->frame_control) || ieee80211_is_probe_resp(hdr->frame_control) || ieee80211_is_beacon(hdr->frame_control)) return RX_CONTINUE; return RX_DROP_MONITOR; } #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l)) if (ieee80211_is_data(hdr->frame_control) && is_multicast_ether_addr(hdr->addr1) && mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata)) return RX_DROP_MONITOR; #undef msh_h_get return RX_CONTINUE; } #define SEQ_MODULO 0x1000 #define SEQ_MASK 0xfff static inline int seq_less(u16 sq1, u16 sq2) { return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1); } static inline u16 seq_inc(u16 sq) { return (sq + 1) & SEQ_MASK; } static inline u16 seq_sub(u16 sq1, u16 sq2) { return (sq1 - sq2) & SEQ_MASK; } static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw, struct tid_ampdu_rx *tid_agg_rx, int index, struct sk_buff_head *frames) { struct ieee80211_supported_band *sband; struct ieee80211_rate *rate = NULL; struct sk_buff *skb = tid_agg_rx->reorder_buf[index]; struct ieee80211_rx_status *status; if (!skb) goto no_frame; status = IEEE80211_SKB_RXCB(skb); /* release the reordered frames to stack */ sband = hw->wiphy->bands[status->band]; if (!(status->flag & RX_FLAG_HT)) rate = &sband->bitrates[status->rate_idx]; tid_agg_rx->stored_mpdu_num--; tid_agg_rx->reorder_buf[index] = NULL; __skb_queue_tail(frames, skb); no_frame: tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); } static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw, struct tid_ampdu_rx *tid_agg_rx, u16 head_seq_num, struct sk_buff_head *frames) { int index; while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) { index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size; ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames); } } /* * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If * the skb was added to the buffer longer than this time ago, the earlier * frames that have not yet been received are assumed to be lost and the skb * can be released for processing. This may also release other skb's from the * reorder buffer if there are no additional gaps between the frames. */ #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10) /* * As this function belongs to the RX path it must be under * rcu_read_lock protection. It returns false if the frame * can be processed immediately, true if it was consumed. */ static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw, struct tid_ampdu_rx *tid_agg_rx, struct sk_buff *skb, struct sk_buff_head *frames) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; u16 sc = le16_to_cpu(hdr->seq_ctrl); u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4; u16 head_seq_num, buf_size; int index; buf_size = tid_agg_rx->buf_size; head_seq_num = tid_agg_rx->head_seq_num; /* frame with out of date sequence number */ if (seq_less(mpdu_seq_num, head_seq_num)) { dev_kfree_skb(skb); return true; } /* * If frame the sequence number exceeds our buffering window * size release some previous frames to make room for this one. */ if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) { head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size)); /* release stored frames up to new head to stack */ ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num, frames); } /* Now the new frame is always in the range of the reordering buffer */ index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size; /* check if we already stored this frame */ if (tid_agg_rx->reorder_buf[index]) { dev_kfree_skb(skb); return true; } /* * If the current MPDU is in the right order and nothing else * is stored we can process it directly, no need to buffer it. */ if (mpdu_seq_num == tid_agg_rx->head_seq_num && tid_agg_rx->stored_mpdu_num == 0) { tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); return false; } /* put the frame in the reordering buffer */ tid_agg_rx->reorder_buf[index] = skb; tid_agg_rx->reorder_time[index] = jiffies; tid_agg_rx->stored_mpdu_num++; /* release the buffer until next missing frame */ index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size; if (!tid_agg_rx->reorder_buf[index] && tid_agg_rx->stored_mpdu_num > 1) { /* * No buffers ready to be released, but check whether any * frames in the reorder buffer have timed out. */ int j; int skipped = 1; for (j = (index + 1) % tid_agg_rx->buf_size; j != index; j = (j + 1) % tid_agg_rx->buf_size) { if (!tid_agg_rx->reorder_buf[j]) { skipped++; continue; } if (!time_after(jiffies, tid_agg_rx->reorder_time[j] + HT_RX_REORDER_BUF_TIMEOUT)) break; #ifdef CONFIG_MAC80211_HT_DEBUG if (net_ratelimit()) printk(KERN_DEBUG "%s: release an RX reorder " "frame due to timeout on earlier " "frames\n", wiphy_name(hw->wiphy)); #endif ieee80211_release_reorder_frame(hw, tid_agg_rx, j, frames); /* * Increment the head seq# also for the skipped slots. */ tid_agg_rx->head_seq_num = (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK; skipped = 0; } } else while (tid_agg_rx->reorder_buf[index]) { ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames); index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size; } return true; } /* * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns * true if the MPDU was buffered, false if it should be processed. */ static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx, struct sk_buff_head *frames) { struct sk_buff *skb = rx->skb; struct ieee80211_local *local = rx->local; struct ieee80211_hw *hw = &local->hw; struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; struct sta_info *sta = rx->sta; struct tid_ampdu_rx *tid_agg_rx; u16 sc; int tid; if (!ieee80211_is_data_qos(hdr->frame_control)) goto dont_reorder; /* * filter the QoS data rx stream according to * STA/TID and check if this STA/TID is on aggregation */ if (!sta) goto dont_reorder; tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL) goto dont_reorder; tid_agg_rx = sta->ampdu_mlme.tid_rx[tid]; /* qos null data frames are excluded */ if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC))) goto dont_reorder; /* new, potentially un-ordered, ampdu frame - process it */ /* reset session timer */ if (tid_agg_rx->timeout) mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(tid_agg_rx->timeout)); /* if this mpdu is fragmented - terminate rx aggregation session */ sc = le16_to_cpu(hdr->seq_ctrl); if (sc & IEEE80211_SCTL_FRAG) { ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr, tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP); dev_kfree_skb(skb); return; } if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames)) return; dont_reorder: __skb_queue_tail(frames, skb); } static ieee80211_rx_result debug_noinline ieee80211_rx_h_check(struct ieee80211_rx_data *rx) { struct ieee80211_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(ieee80211_has_retry(hdr->frame_control) && rx->sta->last_seq_ctrl[rx->queue] == hdr->seq_ctrl)) { if (rx->flags & IEEE80211_RX_RA_MATCH) { rx->local->dot11FrameDuplicateCount++; rx->sta->num_duplicates++; } return RX_DROP_MONITOR; } else rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl; } if (unlikely(rx->skb->len < 16)) { I802_DEBUG_INC(rx->local->rx_handlers_drop_short); return RX_DROP_MONITOR; } /* Drop disallowed frame classes based on STA auth/assoc state; * IEEE 802.11, Chap 5.5. * * mac80211 filters 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 (ieee80211_vif_is_mesh(&rx->sdata->vif)) return ieee80211_rx_mesh_check(rx); if (unlikely((ieee80211_is_data(hdr->frame_control) || ieee80211_is_pspoll(hdr->frame_control)) && rx->sdata->vif.type != NL80211_IFTYPE_ADHOC && (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) { if ((!ieee80211_has_fromds(hdr->frame_control) && !ieee80211_has_tods(hdr->frame_control) && ieee80211_is_data(hdr->frame_control)) || !(rx->flags & IEEE80211_RX_RA_MATCH)) { /* Drop IBSS frames and frames for other hosts * silently. */ return RX_DROP_MONITOR; } return RX_DROP_MONITOR; } return RX_CONTINUE; } static ieee80211_rx_result debug_noinline ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) { struct sk_buff *skb = rx->skb; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; int keyidx; int hdrlen; ieee80211_rx_result result = RX_DROP_UNUSABLE; struct ieee80211_key *stakey = NULL; int mmie_keyidx = -1; /* * Key selection 101 * * There are four types of keys: * - GTK (group keys) * - IGTK (group keys for management frames) * - 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 and IGTKs. * Unless, of course, actual WEP keys ("pre-RSNA") are used, then * unicast frames can also use key indices 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. */ /* * No point in finding a key and decrypting if the frame is neither * addressed to us nor a multicast frame. */ if (!(rx->flags & IEEE80211_RX_RA_MATCH)) return RX_CONTINUE; /* start without a key */ rx->key = NULL; if (rx->sta) stakey = rcu_dereference(rx->sta->key); if (!ieee80211_has_protected(hdr->frame_control)) mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb); if (!is_multicast_ether_addr(hdr->addr1) && stakey) { rx->key = stakey; /* Skip decryption if the frame is not protected. */ if (!ieee80211_has_protected(hdr->frame_control)) return RX_CONTINUE; } else if (mmie_keyidx >= 0) { /* Broadcast/multicast robust management frame / BIP */ if ((status->flag & RX_FLAG_DECRYPTED) && (status->flag & RX_FLAG_IV_STRIPPED)) return RX_CONTINUE; if (mmie_keyidx < NUM_DEFAULT_KEYS || mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) return RX_DROP_MONITOR; /* unexpected BIP keyidx */ rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]); } else if (!ieee80211_has_protected(hdr->frame_control)) { /* * The frame was not protected, so skip decryption. However, we * need to set rx->key if there is a key that could have been * used so that the frame may be dropped if encryption would * have been expected. */ struct ieee80211_key *key = NULL; if (ieee80211_is_mgmt(hdr->frame_control) && is_multicast_ether_addr(hdr->addr1) && (key = rcu_dereference(rx->sdata->default_mgmt_key))) rx->key = key; else if ((key = rcu_dereference(rx->sdata->default_key))) rx->key = key; return RX_CONTINUE; } 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 ((status->flag & RX_FLAG_DECRYPTED) && (status->flag & RX_FLAG_IV_STRIPPED)) return RX_CONTINUE; hdrlen = ieee80211_hdrlen(hdr->frame_control); if (rx->skb->len < 8 + hdrlen) return RX_DROP_UNUSABLE; /* 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 { return RX_DROP_MONITOR; } /* Check for weak IVs if possible */ if (rx->sta && rx->key->conf.alg == ALG_WEP && ieee80211_is_data(hdr->frame_control) && (!(status->flag & RX_FLAG_IV_STRIPPED) || !(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; case ALG_AES_CMAC: result = ieee80211_crypto_aes_cmac_decrypt(rx); break; } /* either the frame has been decrypted or will be dropped */ status->flag |= RX_FLAG_DECRYPTED; return result; } static ieee80211_rx_result debug_noinline ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx) { struct ieee80211_local *local; struct ieee80211_hdr *hdr; struct sk_buff *skb; local = rx->local; skb = rx->skb; hdr = (struct ieee80211_hdr *) skb->data; if (!local->pspolling) return RX_CONTINUE; if (!ieee80211_has_fromds(hdr->frame_control)) /* this is not from AP */ return RX_CONTINUE; if (!ieee80211_is_data(hdr->frame_control)) return RX_CONTINUE; if (!ieee80211_has_moredata(hdr->frame_control)) { /* AP has no more frames buffered for us */ local->pspolling = false; return RX_CONTINUE; } /* more data bit is set, let's request a new frame from the AP */ ieee80211_send_pspoll(local, rx->sdata); return RX_CONTINUE; } static void ap_sta_ps_start(struct sta_info *sta) { struct ieee80211_sub_if_data *sdata = sta->sdata; struct ieee80211_local *local = sdata->local; atomic_inc(&sdata->bss->num_sta_ps); set_sta_flags(sta, WLAN_STA_PS_STA); drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta); #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n", sdata->name, sta->sta.addr, sta->sta.aid); #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ } static void ap_sta_ps_end(struct sta_info *sta) { struct ieee80211_sub_if_data *sdata = sta->sdata; atomic_dec(&sdata->bss->num_sta_ps); clear_sta_flags(sta, WLAN_STA_PS_STA); #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n", sdata->name, sta->sta.addr, sta->sta.aid); #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) { #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n", sdata->name, sta->sta.addr, sta->sta.aid); #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ return; } ieee80211_sta_ps_deliver_wakeup(sta); } static ieee80211_rx_result debug_noinline ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) { struct sta_info *sta = rx->sta; struct sk_buff *skb = rx->skb; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; if (!sta) return RX_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 start using different BSSID. */ if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) { u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, NL80211_IFTYPE_ADHOC); if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0) sta->last_rx = jiffies; } else if (!is_multicast_ether_addr(hdr->addr1)) { /* * Mesh beacons will update last_rx when if they are found to * match the current local configuration when processed. */ sta->last_rx = jiffies; } if (!(rx->flags & IEEE80211_RX_RA_MATCH)) return RX_CONTINUE; if (rx->sdata->vif.type == NL80211_IFTYPE_STATION) ieee80211_sta_rx_notify(rx->sdata, hdr); sta->rx_fragments++; sta->rx_bytes += rx->skb->len; sta->last_signal = status->signal; /* * Change STA power saving mode only at the end of a frame * exchange sequence. */ if (!ieee80211_has_morefrags(hdr->frame_control) && (rx->sdata->vif.type == NL80211_IFTYPE_AP || rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) { if (test_sta_flags(sta, WLAN_STA_PS_STA)) { /* * Ignore doze->wake transitions that are * indicated by non-data frames, the standard * is unclear here, but for example going to * PS mode and then scanning would cause a * doze->wake transition for the probe request, * and that is clearly undesirable. */ if (ieee80211_is_data(hdr->frame_control) && !ieee80211_has_pm(hdr->frame_control)) ap_sta_ps_end(sta); } else { if (ieee80211_has_pm(hdr->frame_control)) ap_sta_ps_start(sta); } } /* * Drop (qos-)data::nullfunc frames silently, since they * are used only to control station power saving mode. */ if (ieee80211_is_nullfunc(hdr->frame_control) || ieee80211_is_qos_nullfunc(hdr->frame_control)) { I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc); /* * If we receive a 4-addr nullfunc frame from a STA * that was not moved to a 4-addr STA vlan yet, drop * the frame to the monitor interface, to make sure * that hostapd sees it */ if (ieee80211_has_a4(hdr->frame_control) && (rx->sdata->vif.type == NL80211_IFTYPE_AP || (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !rx->sdata->u.vlan.sta))) return RX_DROP_MONITOR; /* * Update counter and free packet here to avoid * counting this as a dropped packed. */ sta->rx_packets++; dev_kfree_skb(rx->skb); return RX_QUEUED; } return RX_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_VERBOSE_DEBUG struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) entry->skb_list.next->data; printk(KERN_DEBUG "%s: RX reassembly removed oldest " "fragment entry (idx=%d age=%lu seq=%d last_frag=%d " "addr1=%pM addr2=%pM\n", sdata->name, idx, jiffies - entry->first_frag_time, entry->seq, entry->last_frag, hdr->addr1, hdr->addr2); #endif __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, 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; 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; /* * Check ftype and addresses are equal, else check next fragment */ if (((hdr->frame_control ^ f_hdr->frame_control) & cpu_to_le16(IEEE80211_FCTL_FTYPE)) || compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 || compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0) continue; if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) { __skb_queue_purge(&entry->skb_list); continue; } return entry; } return NULL; } static ieee80211_rx_result debug_noinline ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) { struct ieee80211_hdr *hdr; u16 sc; __le16 fc; unsigned int frag, seq; struct ieee80211_fragment_entry *entry; struct sk_buff *skb; hdr = (struct ieee80211_hdr *)rx->skb->data; fc = hdr->frame_control; sc = le16_to_cpu(hdr->seq_ctrl); frag = sc & IEEE80211_SCTL_FRAG; if (likely((!ieee80211_has_morefrags(fc) && 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->queue, &(rx->skb)); if (rx->key && rx->key->conf.alg == ALG_CCMP && ieee80211_has_protected(fc)) { /* 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->queue], CCMP_PN_LEN); } return RX_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, frag, seq, rx->queue, hdr); if (!entry) { I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); return RX_DROP_MONITOR; } /* 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 RX_DROP_UNUSABLE; 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->queue]; if (memcmp(pn, rpn, CCMP_PN_LEN)) return RX_DROP_UNUSABLE; memcpy(entry->last_pn, pn, CCMP_PN_LEN); } skb_pull(rx->skb, ieee80211_hdrlen(fc)); __skb_queue_tail(&entry->skb_list, rx->skb); entry->last_frag = frag; entry->extra_len += rx->skb->len; if (ieee80211_has_morefrags(fc)) { rx->skb = NULL; return RX_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 RX_DROP_UNUSABLE; } } 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_RX_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 RX_CONTINUE; } static ieee80211_rx_result debug_noinline ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx) { struct ieee80211_sub_if_data *sdata = rx->sdata; __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control; if (likely(!rx->sta || !ieee80211_is_pspoll(fc) || !(rx->flags & IEEE80211_RX_RA_MATCH))) return RX_CONTINUE; if ((sdata->vif.type != NL80211_IFTYPE_AP) && (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)) return RX_DROP_UNUSABLE; if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER)) ieee80211_sta_ps_deliver_poll_response(rx->sta); else set_sta_flags(rx->sta, WLAN_STA_PSPOLL); /* Free PS Poll skb here instead of returning RX_DROP that would * count as an dropped frame. */ dev_kfree_skb(rx->skb); return RX_QUEUED; } static ieee80211_rx_result debug_noinline ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx) { u8 *data = rx->skb->data; struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data; if (!ieee80211_is_data_qos(hdr->frame_control)) return RX_CONTINUE; /* remove the qos control field, update frame type and meta-data */ memmove(data + IEEE80211_QOS_CTL_LEN, data, ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN); hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN); /* change frame type to non QOS */ hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA); return RX_CONTINUE; } static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx) { if (unlikely(!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED))) return -EACCES; return 0; } static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc) { struct sk_buff *skb = rx->skb; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); /* * Pass through unencrypted frames if the hardware has * decrypted them already. */ if (status->flag & RX_FLAG_DECRYPTED) return 0; /* Drop unencrypted frames if key is set. */ if (unlikely(!ieee80211_has_protected(fc) && !ieee80211_is_nullfunc(fc) && ieee80211_is_data(fc) && (rx->key || rx->sdata->drop_unencrypted))) return -EACCES; return 0; } static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; __le16 fc = hdr->frame_control; int res; res = ieee80211_drop_unencrypted(rx, fc); if (unlikely(res)) return res; if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) { if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) && rx->key)) return -EACCES; /* BIP does not use Protected field, so need to check MMIE */ if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) && ieee80211_get_mmie_keyidx(rx->skb) < 0 && rx->key)) return -EACCES; /* * When using MFP, Action frames are not allowed prior to * having configured keys. */ if (unlikely(ieee80211_is_action(fc) && !rx->key && ieee80211_is_robust_mgmt_frame( (struct ieee80211_hdr *) rx->skb->data))) return -EACCES; } return 0; } static int __ieee80211_data_to_8023(struct ieee80211_rx_data *rx) { struct ieee80211_sub_if_data *sdata = rx->sdata; struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; if (ieee80211_has_a4(hdr->frame_control) && sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta) return -1; if (is_multicast_ether_addr(hdr->addr1) && ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) || (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr))) return -1; return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type); } /* * requires that rx->skb is a frame with ethernet header */ static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc) { static const u8 pae_group_addr[ETH_ALEN] __aligned(2) = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 }; struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; /* * Allow EAPOL frames to us/the PAE group address regardless * of whether the frame was encrypted or not. */ if (ehdr->h_proto == htons(ETH_P_PAE) && (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 || compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0)) return true; if (ieee80211_802_1x_port_control(rx) || ieee80211_drop_unencrypted(rx, fc)) return false; return true; } /* * requires that rx->skb is a frame with ethernet header */ static void ieee80211_deliver_skb(struct ieee80211_rx_data *rx) { struct ieee80211_sub_if_data *sdata = rx->sdata; struct net_device *dev = sdata->dev; struct sk_buff *skb, *xmit_skb; struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; struct sta_info *dsta; skb = rx->skb; xmit_skb = NULL; if ((sdata->vif.type == NL80211_IFTYPE_AP || sdata->vif.type == NL80211_IFTYPE_AP_VLAN) && !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) && (rx->flags & IEEE80211_RX_RA_MATCH) && (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) { if (is_multicast_ether_addr(ehdr->h_dest)) { /* * send multicast frames both to higher layers in * local net stack and back to the wireless medium */ xmit_skb = skb_copy(skb, GFP_ATOMIC); if (!xmit_skb && net_ratelimit()) printk(KERN_DEBUG "%s: failed to clone " "multicast frame\n", dev->name); } else { dsta = sta_info_get(sdata, skb->data); if (dsta) { /* * The destination station is associated to * this AP (in this VLAN), so send the frame * directly to it and do not pass it to local * net stack. */ xmit_skb = skb; skb = NULL; } } } if (skb) { int align __maybe_unused; #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS /* * 'align' will only take the values 0 or 2 here * since all frames are required to be aligned * to 2-byte boundaries when being passed to * mac80211. That also explains the __skb_push() * below. */ align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3; if (align) { if (WARN_ON(skb_headroom(skb) < 3)) { dev_kfree_skb(skb); skb = NULL; } else { u8 *data = skb->data; size_t len = skb_headlen(skb); skb->data -= align; memmove(skb->data, data, len); skb_set_tail_pointer(skb, len); } } #endif if (skb) { /* deliver to local stack */ skb->protocol = eth_type_trans(skb, dev); memset(skb->cb, 0, sizeof(skb->cb)); netif_rx(skb); } } if (xmit_skb) { /* send to wireless media */ xmit_skb->protocol = htons(ETH_P_802_3); skb_reset_network_header(xmit_skb); skb_reset_mac_header(xmit_skb); dev_queue_xmit(xmit_skb); } } static ieee80211_rx_result debug_noinline ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx) { struct net_device *dev = rx->sdata->dev; struct sk_buff *skb = rx->skb; struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; __le16 fc = hdr->frame_control; struct sk_buff_head frame_list; if (unlikely(!ieee80211_is_data(fc))) return RX_CONTINUE; if (unlikely(!ieee80211_is_data_present(fc))) return RX_DROP_MONITOR; if (!(rx->flags & IEEE80211_RX_AMSDU)) return RX_CONTINUE; if (ieee80211_has_a4(hdr->frame_control) && rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !rx->sdata->u.vlan.sta) return RX_DROP_UNUSABLE; if (is_multicast_ether_addr(hdr->addr1) && ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && rx->sdata->u.vlan.sta) || (rx->sdata->vif.type == NL80211_IFTYPE_STATION && rx->sdata->u.mgd.use_4addr))) return RX_DROP_UNUSABLE; skb->dev = dev; __skb_queue_head_init(&frame_list); ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr, rx->sdata->vif.type, rx->local->hw.extra_tx_headroom); while (!skb_queue_empty(&frame_list)) { rx->skb = __skb_dequeue(&frame_list); if (!ieee80211_frame_allowed(rx, fc)) { dev_kfree_skb(rx->skb); continue; } dev->stats.rx_packets++; dev->stats.rx_bytes += rx->skb->len; ieee80211_deliver_skb(rx); } return RX_QUEUED; } #ifdef CONFIG_MAC80211_MESH static ieee80211_rx_result ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx) { struct ieee80211_hdr *hdr; struct ieee80211s_hdr *mesh_hdr; unsigned int hdrlen; struct sk_buff *skb = rx->skb, *fwd_skb; struct ieee80211_local *local = rx->local; struct ieee80211_sub_if_data *sdata = rx->sdata; hdr = (struct ieee80211_hdr *) skb->data; hdrlen = ieee80211_hdrlen(hdr->frame_control); mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); if (!ieee80211_is_data(hdr->frame_control)) return RX_CONTINUE; if (!mesh_hdr->ttl) /* illegal frame */ return RX_DROP_MONITOR; if (mesh_hdr->flags & MESH_FLAGS_AE) { struct mesh_path *mppath; char *proxied_addr; char *mpp_addr; if (is_multicast_ether_addr(hdr->addr1)) { mpp_addr = hdr->addr3; proxied_addr = mesh_hdr->eaddr1; } else { mpp_addr = hdr->addr4; proxied_addr = mesh_hdr->eaddr2; } rcu_read_lock(); mppath = mpp_path_lookup(proxied_addr, sdata); if (!mppath) { mpp_path_add(proxied_addr, mpp_addr, sdata); } else { spin_lock_bh(&mppath->state_lock); if (compare_ether_addr(mppath->mpp, mpp_addr) != 0) memcpy(mppath->mpp, mpp_addr, ETH_ALEN); spin_unlock_bh(&mppath->state_lock); } rcu_read_unlock(); } /* Frame has reached destination. Don't forward */ if (!is_multicast_ether_addr(hdr->addr1) && compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0) return RX_CONTINUE; mesh_hdr->ttl--; if (rx->flags & IEEE80211_RX_RA_MATCH) { if (!mesh_hdr->ttl) IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh, dropped_frames_ttl); else { struct ieee80211_hdr *fwd_hdr; struct ieee80211_tx_info *info; fwd_skb = skb_copy(skb, GFP_ATOMIC); if (!fwd_skb && net_ratelimit()) printk(KERN_DEBUG "%s: failed to clone mesh frame\n", sdata->name); fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data; memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN); info = IEEE80211_SKB_CB(fwd_skb); memset(info, 0, sizeof(*info)); info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; info->control.vif = &rx->sdata->vif; skb_set_queue_mapping(skb, ieee80211_select_queue(rx->sdata, fwd_skb)); ieee80211_set_qos_hdr(local, skb); if (is_multicast_ether_addr(fwd_hdr->addr1)) IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, fwded_mcast); else { int err; /* * Save TA to addr1 to send TA a path error if a * suitable next hop is not found */ memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN); err = mesh_nexthop_lookup(fwd_skb, sdata); /* Failed to immediately resolve next hop: * fwded frame was dropped or will be added * later to the pending skb queue. */ if (err) return RX_DROP_MONITOR; IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, fwded_unicast); } IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, fwded_frames); ieee80211_add_pending_skb(local, fwd_skb); } } if (is_multicast_ether_addr(hdr->addr1) || sdata->dev->flags & IFF_PROMISC) return RX_CONTINUE; else return RX_DROP_MONITOR; } #endif static ieee80211_rx_result debug_noinline ieee80211_rx_h_data(struct ieee80211_rx_data *rx) { struct ieee80211_sub_if_data *sdata = rx->sdata; struct ieee80211_local *local = rx->local; struct net_device *dev = sdata->dev; struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; __le16 fc = hdr->frame_control; int err; if (unlikely(!ieee80211_is_data(hdr->frame_control))) return RX_CONTINUE; if (unlikely(!ieee80211_is_data_present(hdr->frame_control))) return RX_DROP_MONITOR; /* * Allow the cooked monitor interface of an AP to see 4-addr frames so * that a 4-addr station can be detected and moved into a separate VLAN */ if (ieee80211_has_a4(hdr->frame_control) && sdata->vif.type == NL80211_IFTYPE_AP) return RX_DROP_MONITOR; err = __ieee80211_data_to_8023(rx); if (unlikely(err)) return RX_DROP_UNUSABLE; if (!ieee80211_frame_allowed(rx, fc)) return RX_DROP_MONITOR; rx->skb->dev = dev; dev->stats.rx_packets++; dev->stats.rx_bytes += rx->skb->len; if (ieee80211_is_data(hdr->frame_control) && !is_multicast_ether_addr(hdr->addr1) && local->hw.conf.dynamic_ps_timeout > 0 && local->ps_sdata) { mod_timer(&local->dynamic_ps_timer, jiffies + msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); } ieee80211_deliver_skb(rx); return RX_QUEUED; } static ieee80211_rx_result debug_noinline ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames) { struct ieee80211_local *local = rx->local; struct ieee80211_hw *hw = &local->hw; struct sk_buff *skb = rx->skb; struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data; struct tid_ampdu_rx *tid_agg_rx; u16 start_seq_num; u16 tid; if (likely(!ieee80211_is_ctl(bar->frame_control))) return RX_CONTINUE; if (ieee80211_is_back_req(bar->frame_control)) { if (!rx->sta) return RX_DROP_MONITOR; tid = le16_to_cpu(bar->control) >> 12; if (rx->sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL) return RX_DROP_MONITOR; tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid]; start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4; /* reset session timer */ if (tid_agg_rx->timeout) mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(tid_agg_rx->timeout)); /* release stored frames up to start of BAR */ ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num, frames); kfree_skb(skb); return RX_QUEUED; } return RX_CONTINUE; } static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt, size_t len) { struct ieee80211_local *local = sdata->local; struct sk_buff *skb; struct ieee80211_mgmt *resp; if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) { /* Not to own unicast address */ return; } if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 || compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) { /* Not from the current AP or not associated yet. */ return; } if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) { /* Too short SA Query request frame */ return; } skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom); if (skb == NULL) return; skb_reserve(skb, local->hw.extra_tx_headroom); resp = (struct ieee80211_mgmt *) skb_put(skb, 24); memset(resp, 0, 24); memcpy(resp->da, mgmt->sa, ETH_ALEN); memcpy(resp->sa, sdata->vif.addr, ETH_ALEN); memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN); resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_ACTION); skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query)); resp->u.action.category = WLAN_CATEGORY_SA_QUERY; resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE; memcpy(resp->u.action.u.sa_query.trans_id, mgmt->u.action.u.sa_query.trans_id, WLAN_SA_QUERY_TR_ID_LEN); ieee80211_tx_skb(sdata, skb); } static ieee80211_rx_result debug_noinline ieee80211_rx_h_action(struct ieee80211_rx_data *rx) { struct ieee80211_local *local = rx->local; struct ieee80211_sub_if_data *sdata = rx->sdata; struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; struct sk_buff *nskb; struct ieee80211_rx_status *status; int len = rx->skb->len; if (!ieee80211_is_action(mgmt->frame_control)) return RX_CONTINUE; /* drop too small frames */ if (len < IEEE80211_MIN_ACTION_SIZE) return RX_DROP_UNUSABLE; if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC) return RX_DROP_UNUSABLE; if (!(rx->flags & IEEE80211_RX_RA_MATCH)) return RX_DROP_UNUSABLE; if (ieee80211_drop_unencrypted_mgmt(rx)) return RX_DROP_UNUSABLE; switch (mgmt->u.action.category) { case WLAN_CATEGORY_BACK: /* * The aggregation code is not prepared to handle * anything but STA/AP due to the BSSID handling; * IBSS could work in the code but isn't supported * by drivers or the standard. */ if (sdata->vif.type != NL80211_IFTYPE_STATION && sdata->vif.type != NL80211_IFTYPE_AP_VLAN && sdata->vif.type != NL80211_IFTYPE_AP) break; /* verify action_code is present */ if (len < IEEE80211_MIN_ACTION_SIZE + 1) break; switch (mgmt->u.action.u.addba_req.action_code) { case WLAN_ACTION_ADDBA_REQ: if (len < (IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.addba_req))) return RX_DROP_MONITOR; ieee80211_process_addba_request(local, rx->sta, mgmt, len); goto handled; case WLAN_ACTION_ADDBA_RESP: if (len < (IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.addba_resp))) break; ieee80211_process_addba_resp(local, rx->sta, mgmt, len); goto handled; case WLAN_ACTION_DELBA: if (len < (IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.delba))) break; ieee80211_process_delba(sdata, rx->sta, mgmt, len); goto handled; } break; case WLAN_CATEGORY_SPECTRUM_MGMT: if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ) break; if (sdata->vif.type != NL80211_IFTYPE_STATION) break; /* verify action_code is present */ if (len < IEEE80211_MIN_ACTION_SIZE + 1) break; switch (mgmt->u.action.u.measurement.action_code) { case WLAN_ACTION_SPCT_MSR_REQ: if (len < (IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.measurement))) break; ieee80211_process_measurement_req(sdata, mgmt, len); goto handled; case WLAN_ACTION_SPCT_CHL_SWITCH: if (len < (IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.chan_switch))) break; if (sdata->vif.type != NL80211_IFTYPE_STATION) break; if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN)) break; return ieee80211_sta_rx_mgmt(sdata, rx->skb); } break; case WLAN_CATEGORY_SA_QUERY: if (len < (IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.sa_query))) break; switch (mgmt->u.action.u.sa_query.action) { case WLAN_ACTION_SA_QUERY_REQUEST: if (sdata->vif.type != NL80211_IFTYPE_STATION) break; ieee80211_process_sa_query_req(sdata, mgmt, len); goto handled; } break; } /* * For AP mode, hostapd is responsible for handling any action * frames that we didn't handle, including returning unknown * ones. For all other modes we will return them to the sender, * setting the 0x80 bit in the action category, as required by * 802.11-2007 7.3.1.11. */ if (sdata->vif.type == NL80211_IFTYPE_AP || sdata->vif.type == NL80211_IFTYPE_AP_VLAN) return RX_DROP_MONITOR; /* * Getting here means the kernel doesn't know how to handle * it, but maybe userspace does ... include returned frames * so userspace can register for those to know whether ones * it transmitted were processed or returned. */ status = IEEE80211_SKB_RXCB(rx->skb); if (sdata->vif.type == NL80211_IFTYPE_STATION && cfg80211_rx_action(rx->sdata->dev, status->freq, rx->skb->data, rx->skb->len, GFP_ATOMIC)) goto handled; /* do not return rejected action frames */ if (mgmt->u.action.category & 0x80) return RX_DROP_UNUSABLE; nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0, GFP_ATOMIC); if (nskb) { struct ieee80211_mgmt *mgmt = (void *)nskb->data; mgmt->u.action.category |= 0x80; memcpy(mgmt->da, mgmt->sa, ETH_ALEN); memcpy(mgmt->sa, rx->sdata->vif.addr, ETH_ALEN); memset(nskb->cb, 0, sizeof(nskb->cb)); ieee80211_tx_skb(rx->sdata, nskb); } handled: if (rx->sta) rx->sta->rx_packets++; dev_kfree_skb(rx->skb); return RX_QUEUED; } static ieee80211_rx_result debug_noinline ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx) { struct ieee80211_sub_if_data *sdata = rx->sdata; ieee80211_rx_result rxs; if (!(rx->flags & IEEE80211_RX_RA_MATCH)) return RX_DROP_MONITOR; if (ieee80211_drop_unencrypted_mgmt(rx)) return RX_DROP_UNUSABLE; rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb); if (rxs != RX_CONTINUE) return rxs; if (ieee80211_vif_is_mesh(&sdata->vif)) return ieee80211_mesh_rx_mgmt(sdata, rx->skb); if (sdata->vif.type == NL80211_IFTYPE_ADHOC) return ieee80211_ibss_rx_mgmt(sdata, rx->skb); if (sdata->vif.type == NL80211_IFTYPE_STATION) return ieee80211_sta_rx_mgmt(sdata, rx->skb); return RX_DROP_MONITOR; } static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr, struct ieee80211_rx_data *rx) { int keyidx; unsigned int hdrlen; hdrlen = ieee80211_hdrlen(hdr->frame_control); if (rx->skb->len >= hdrlen + 4) keyidx = rx->skb->data[hdrlen + 3] >> 6; else keyidx = -1; if (!rx->sta) { /* * Some hardware seem to generate incorrect Michael MIC * reports; ignore them to avoid triggering countermeasures. */ return; } if (!ieee80211_has_protected(hdr->frame_control)) return; if (rx->sdata->vif.type == NL80211_IFTYPE_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. */ return; } if (!ieee80211_is_data(hdr->frame_control) && !ieee80211_is_auth(hdr->frame_control)) return; mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL, GFP_ATOMIC); } /* TODO: use IEEE80211_RX_FRAGMENTED */ static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx, struct ieee80211_rate *rate) { struct ieee80211_sub_if_data *sdata; struct ieee80211_local *local = rx->local; struct ieee80211_rtap_hdr { struct ieee80211_radiotap_header hdr; u8 flags; u8 rate_or_pad; __le16 chan_freq; __le16 chan_flags; } __attribute__ ((packed)) *rthdr; struct sk_buff *skb = rx->skb, *skb2; struct net_device *prev_dev = NULL; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); if (status->flag & RX_FLAG_INTERNAL_CMTR) goto out_free_skb; if (skb_headroom(skb) < sizeof(*rthdr) && pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) goto out_free_skb; 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_CHANNEL)); if (rate) { rthdr->rate_or_pad = rate->bitrate / 5; rthdr->hdr.it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); } rthdr->chan_freq = cpu_to_le16(status->freq); if (status->band == IEEE80211_BAND_5GHZ) 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); 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 (!ieee80211_sdata_running(sdata)) continue; if (sdata->vif.type != NL80211_IFTYPE_MONITOR || !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)) 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); skb = NULL; } else goto out_free_skb; status->flag |= RX_FLAG_INTERNAL_CMTR; return; out_free_skb: dev_kfree_skb(skb); } static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata, struct ieee80211_rx_data *rx, struct sk_buff *skb, struct ieee80211_rate *rate) { struct sk_buff_head reorder_release; ieee80211_rx_result res = RX_DROP_MONITOR; __skb_queue_head_init(&reorder_release); rx->skb = skb; rx->sdata = sdata; #define CALL_RXH(rxh) \ do { \ res = rxh(rx); \ if (res != RX_CONTINUE) \ goto rxh_next; \ } while (0); /* * NB: the rxh_next label works even if we jump * to it from here because then the list will * be empty, which is a trivial check */ CALL_RXH(ieee80211_rx_h_passive_scan) CALL_RXH(ieee80211_rx_h_check) ieee80211_rx_reorder_ampdu(rx, &reorder_release); while ((skb = __skb_dequeue(&reorder_release))) { /* * all the other fields are valid across frames * that belong to an aMPDU since they are on the * same TID from the same station */ rx->skb = skb; CALL_RXH(ieee80211_rx_h_decrypt) CALL_RXH(ieee80211_rx_h_check_more_data) CALL_RXH(ieee80211_rx_h_sta_process) CALL_RXH(ieee80211_rx_h_defragment) CALL_RXH(ieee80211_rx_h_ps_poll) CALL_RXH(ieee80211_rx_h_michael_mic_verify) /* must be after MMIC verify so header is counted in MPDU mic */ CALL_RXH(ieee80211_rx_h_remove_qos_control) CALL_RXH(ieee80211_rx_h_amsdu) #ifdef CONFIG_MAC80211_MESH if (ieee80211_vif_is_mesh(&sdata->vif)) CALL_RXH(ieee80211_rx_h_mesh_fwding); #endif CALL_RXH(ieee80211_rx_h_data) /* special treatment -- needs the queue */ res = ieee80211_rx_h_ctrl(rx, &reorder_release); if (res != RX_CONTINUE) goto rxh_next; CALL_RXH(ieee80211_rx_h_action) CALL_RXH(ieee80211_rx_h_mgmt) #undef CALL_RXH rxh_next: switch (res) { case RX_DROP_MONITOR: I802_DEBUG_INC(sdata->local->rx_handlers_drop); if (rx->sta) rx->sta->rx_dropped++; /* fall through */ case RX_CONTINUE: ieee80211_rx_cooked_monitor(rx, rate); break; case RX_DROP_UNUSABLE: I802_DEBUG_INC(sdata->local->rx_handlers_drop); if (rx->sta) rx->sta->rx_dropped++; dev_kfree_skb(rx->skb); break; case RX_QUEUED: I802_DEBUG_INC(sdata->local->rx_handlers_queued); break; } } } /* main receive path */ static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata, struct ieee80211_rx_data *rx, struct ieee80211_hdr *hdr) { struct sk_buff *skb = rx->skb; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type); int multicast = is_multicast_ether_addr(hdr->addr1); switch (sdata->vif.type) { case NL80211_IFTYPE_STATION: if (!bssid && !sdata->u.mgd.use_4addr) return 0; if (!multicast && compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) { if (!(sdata->dev->flags & IFF_PROMISC)) return 0; rx->flags &= ~IEEE80211_RX_RA_MATCH; } break; case NL80211_IFTYPE_ADHOC: if (!bssid) return 0; if (ieee80211_is_beacon(hdr->frame_control)) { return 1; } else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) { if (!(rx->flags & IEEE80211_RX_IN_SCAN)) return 0; rx->flags &= ~IEEE80211_RX_RA_MATCH; } else if (!multicast && compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) { if (!(sdata->dev->flags & IFF_PROMISC)) return 0; rx->flags &= ~IEEE80211_RX_RA_MATCH; } else if (!rx->sta) { int rate_idx; if (status->flag & RX_FLAG_HT) rate_idx = 0; /* TODO: HT rates */ else rate_idx = status->rate_idx; rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2, BIT(rate_idx), GFP_ATOMIC); } break; case NL80211_IFTYPE_MESH_POINT: if (!multicast && compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) { if (!(sdata->dev->flags & IFF_PROMISC)) return 0; rx->flags &= ~IEEE80211_RX_RA_MATCH; } break; case NL80211_IFTYPE_AP_VLAN: case NL80211_IFTYPE_AP: if (!bssid) { if (compare_ether_addr(sdata->vif.addr, hdr->addr1)) return 0; } else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) { if (!(rx->flags & IEEE80211_RX_IN_SCAN)) return 0; rx->flags &= ~IEEE80211_RX_RA_MATCH; } break; case NL80211_IFTYPE_WDS: if (bssid || !ieee80211_is_data(hdr->frame_control)) return 0; if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) return 0; break; case NL80211_IFTYPE_MONITOR: case NL80211_IFTYPE_UNSPECIFIED: case __NL80211_IFTYPE_AFTER_LAST: /* should never get here */ WARN_ON(1); break; } return 1; } /* * This is the actual Rx frames handler. as it blongs to Rx path it must * be called with rcu_read_lock protection. */ static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, struct sk_buff *skb, struct ieee80211_rate *rate) { struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_sub_if_data *sdata; struct ieee80211_hdr *hdr; struct ieee80211_rx_data rx; int prepares; struct ieee80211_sub_if_data *prev = NULL; struct sk_buff *skb_new; struct sta_info *sta, *tmp; bool found_sta = false; hdr = (struct ieee80211_hdr *)skb->data; memset(&rx, 0, sizeof(rx)); rx.skb = skb; rx.local = local; if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control)) local->dot11ReceivedFragmentCount++; if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) || test_bit(SCAN_OFF_CHANNEL, &local->scanning))) rx.flags |= IEEE80211_RX_IN_SCAN; ieee80211_parse_qos(&rx); ieee80211_verify_alignment(&rx); if (ieee80211_is_data(hdr->frame_control)) { for_each_sta_info(local, hdr->addr2, sta, tmp) { rx.sta = sta; found_sta = true; rx.sdata = sta->sdata; rx.flags |= IEEE80211_RX_RA_MATCH; prepares = prepare_for_handlers(rx.sdata, &rx, hdr); if (prepares) { if (status->flag & RX_FLAG_MMIC_ERROR) { if (rx.flags & IEEE80211_RX_RA_MATCH) ieee80211_rx_michael_mic_report(hdr, &rx); } else prev = rx.sdata; } } } if (!found_sta) { list_for_each_entry_rcu(sdata, &local->interfaces, list) { if (!ieee80211_sdata_running(sdata)) continue; if (sdata->vif.type == NL80211_IFTYPE_MONITOR || sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 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; } rx.sta = sta_info_get_bss(prev, hdr->addr2); rx.flags |= IEEE80211_RX_RA_MATCH; prepares = prepare_for_handlers(prev, &rx, hdr); if (!prepares) goto next; if (status->flag & RX_FLAG_MMIC_ERROR) { rx.sdata = prev; if (rx.flags & IEEE80211_RX_RA_MATCH) ieee80211_rx_michael_mic_report(hdr, &rx); goto next; } /* * 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\n", wiphy_name(local->hw.wiphy), prev->name); goto next; } ieee80211_invoke_rx_handlers(prev, &rx, skb_new, rate); next: prev = sdata; } if (prev) { rx.sta = sta_info_get_bss(prev, hdr->addr2); rx.flags |= IEEE80211_RX_RA_MATCH; prepares = prepare_for_handlers(prev, &rx, hdr); if (!prepares) prev = NULL; } } if (prev) ieee80211_invoke_rx_handlers(prev, &rx, skb, rate); else dev_kfree_skb(skb); } /* * 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_local *local = hw_to_local(hw); struct ieee80211_rate *rate = NULL; struct ieee80211_supported_band *sband; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); WARN_ON_ONCE(softirq_count() == 0); if (WARN_ON(status->band < 0 || status->band >= IEEE80211_NUM_BANDS)) goto drop; sband = local->hw.wiphy->bands[status->band]; if (WARN_ON(!sband)) goto drop; /* * If we're suspending, it is possible although not too likely * that we'd be receiving frames after having already partially * quiesced the stack. We can't process such frames then since * that might, for example, cause stations to be added or other * driver callbacks be invoked. */ if (unlikely(local->quiescing || local->suspended)) goto drop; /* * The same happens when we're not even started, * but that's worth a warning. */ if (WARN_ON(!local->started)) goto drop; if (status->flag & RX_FLAG_HT) { /* * rate_idx is MCS index, which can be [0-76] as documented on: * * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n * * Anything else would be some sort of driver or hardware error. * The driver should catch hardware errors. */ if (WARN((status->rate_idx < 0 || status->rate_idx > 76), "Rate marked as an HT rate but passed " "status->rate_idx is not " "an MCS index [0-76]: %d (0x%02x)\n", status->rate_idx, status->rate_idx)) goto drop; } else { if (WARN_ON(status->rate_idx < 0 || status->rate_idx >= sband->n_bitrates)) goto drop; rate = &sband->bitrates[status->rate_idx]; } /* * 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, rate); if (!skb) { rcu_read_unlock(); return; } __ieee80211_rx_handle_packet(hw, skb, rate); rcu_read_unlock(); return; drop: kfree_skb(skb); } 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_local *local = hw_to_local(hw); BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); skb->pkt_type = IEEE80211_RX_MSG; skb_queue_tail(&local->skb_queue, skb); tasklet_schedule(&local->tasklet); } EXPORT_SYMBOL(ieee80211_rx_irqsafe);