/* * 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 #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" #include "rate.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) { struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) { if (likely(skb->len > FCS_LEN)) __pskb_trim(skb, skb->len - FCS_LEN); else { /* driver bug */ WARN_ON(1); dev_kfree_skb(skb); skb = NULL; } } if (status->vendor_radiotap_len) __pskb_pull(skb, status->vendor_radiotap_len); 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; hdr = (void *)(skb->data + status->vendor_radiotap_len); if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC | RX_FLAG_AMPDU_IS_ZEROLEN)) return 1; if (unlikely(skb->len < 16 + present_fcs_len + status->vendor_radiotap_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_space(struct ieee80211_local *local, struct ieee80211_rx_status *status) { int len; /* always present fields */ len = sizeof(struct ieee80211_radiotap_header) + 9; /* allocate extra bitmap */ if (status->vendor_radiotap_len) len += 4; if (ieee80211_have_rx_timestamp(status)) { len = ALIGN(len, 8); len += 8; } if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) len += 1; /* padding for RX_FLAGS if necessary */ len = ALIGN(len, 2); if (status->flag & RX_FLAG_HT) /* HT info */ len += 3; if (status->flag & RX_FLAG_AMPDU_DETAILS) { len = ALIGN(len, 4); len += 8; } if (status->vendor_radiotap_len) { if (WARN_ON_ONCE(status->vendor_radiotap_align == 0)) status->vendor_radiotap_align = 1; /* align standard part of vendor namespace */ len = ALIGN(len, 2); /* allocate standard part of vendor namespace */ len += 6; /* align vendor-defined part */ len = ALIGN(len, status->vendor_radiotap_align); /* vendor-defined part is already in skb */ } 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, bool has_fcs) { struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); struct ieee80211_radiotap_header *rthdr; unsigned char *pos; u16 rx_flags = 0; int mpdulen; mpdulen = skb->len; if (!(has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))) mpdulen += FCS_LEN; 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 + status->vendor_radiotap_len); pos = (unsigned char *)(rthdr + 1); if (status->vendor_radiotap_len) { rthdr->it_present |= cpu_to_le32(BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE)) | cpu_to_le32(BIT(IEEE80211_RADIOTAP_EXT)); put_unaligned_le32(status->vendor_radiotap_bitmap, pos); pos += 4; } /* the order of the following fields is important */ /* IEEE80211_RADIOTAP_TSFT */ if (ieee80211_have_rx_timestamp(status)) { /* padding */ while ((pos - (u8 *)rthdr) & 7) *pos++ = 0; put_unaligned_le64( ieee80211_calculate_rx_timestamp(local, status, mpdulen, 0), pos); rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT); pos += 8; } /* IEEE80211_RADIOTAP_FLAGS */ if (has_fcs && (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 (!rate || status->flag & RX_FLAG_HT) { /* * Without rate information don't add it. If we have, * MCS information is a separate field in radiotap, * added below. The byte here is needed as padding * for the channel though, so initialise it to 0. */ *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 && rate->flags & IEEE80211_RATE_ERP_G) put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ, pos); else if (rate) put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ, pos); else put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos); pos += 2; /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */ if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM && !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) { *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++ = 0; if (status->flag & RX_FLAG_FAILED_PLCP_CRC) rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP; put_unaligned_le16(rx_flags, pos); pos += 2; if (status->flag & RX_FLAG_HT) { rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS); *pos++ = local->hw.radiotap_mcs_details; *pos = 0; if (status->flag & RX_FLAG_SHORT_GI) *pos |= IEEE80211_RADIOTAP_MCS_SGI; if (status->flag & RX_FLAG_40MHZ) *pos |= IEEE80211_RADIOTAP_MCS_BW_40; if (status->flag & RX_FLAG_HT_GF) *pos |= IEEE80211_RADIOTAP_MCS_FMT_GF; pos++; *pos++ = status->rate_idx; } if (status->flag & RX_FLAG_AMPDU_DETAILS) { u16 flags = 0; /* ensure 4 byte alignment */ while ((pos - (u8 *)rthdr) & 3) pos++; rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS); put_unaligned_le32(status->ampdu_reference, pos); pos += 4; if (status->flag & RX_FLAG_AMPDU_REPORT_ZEROLEN) flags |= IEEE80211_RADIOTAP_AMPDU_REPORT_ZEROLEN; if (status->flag & RX_FLAG_AMPDU_IS_ZEROLEN) flags |= IEEE80211_RADIOTAP_AMPDU_IS_ZEROLEN; if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN) flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN; if (status->flag & RX_FLAG_AMPDU_IS_LAST) flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST; if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR) flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR; if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN) flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN; put_unaligned_le16(flags, pos); pos += 2; if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN) *pos++ = status->ampdu_delimiter_crc; else *pos++ = 0; *pos++ = 0; } if (status->vendor_radiotap_len) { /* ensure 2 byte alignment for the vendor field as required */ if ((pos - (u8 *)rthdr) & 1) *pos++ = 0; *pos++ = status->vendor_radiotap_oui[0]; *pos++ = status->vendor_radiotap_oui[1]; *pos++ = status->vendor_radiotap_oui[2]; *pos++ = status->vendor_radiotap_subns; put_unaligned_le16(status->vendor_radiotap_len, pos); pos += 2; /* align the actual payload as requested */ while ((pos - (u8 *)rthdr) & (status->vendor_radiotap_align - 1)) *pos++ = 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_rate *rate) { struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb); struct ieee80211_sub_if_data *sdata; int needed_headroom; 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_space(local, status); if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) present_fcs_len = FCS_LEN; /* ensure hdr->frame_control and vendor radiotap data are in skb head */ if (!pskb_may_pull(origskb, 2 + status->vendor_radiotap_len)) { dev_kfree_skb(origskb); return NULL; } 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, true); 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_receive_skb(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_receive_skb(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; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); int tid, seqno_idx, security_idx; /* 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_CTL_A_MSDU_PRESENT) status->rx_flags |= IEEE80211_RX_AMSDU; seqno_idx = tid; security_idx = tid; } 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. */ seqno_idx = IEEE80211_NUM_TIDS; security_idx = 0; if (ieee80211_is_mgmt(hdr->frame_control)) security_idx = IEEE80211_NUM_TIDS; tid = 0; } rx->seqno_idx = seqno_idx; rx->security_idx = security_idx; /* 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 between 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 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; 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 (ether_addr_equal(hdr->addr3, dev_addr)) return RX_DROP_MONITOR; } else { if (!ieee80211_has_a4(hdr->frame_control)) return RX_DROP_MONITOR; if (ether_addr_equal(hdr->addr4, dev_addr)) 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) != NL80211_PLINK_ESTAB) { struct ieee80211_mgmt *mgmt; if (!ieee80211_is_mgmt(hdr->frame_control)) return RX_DROP_MONITOR; if (ieee80211_is_action(hdr->frame_control)) { u8 category; /* make sure category field is present */ if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE) return RX_DROP_MONITOR; mgmt = (struct ieee80211_mgmt *)hdr; category = mgmt->u.action.category; if (category != WLAN_CATEGORY_MESH_ACTION && category != WLAN_CATEGORY_SELF_PROTECTED) 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) || ieee80211_is_auth(hdr->frame_control)) return RX_CONTINUE; return RX_DROP_MONITOR; } 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_sub_if_data *sdata, struct tid_ampdu_rx *tid_agg_rx, int index) { struct ieee80211_local *local = sdata->local; struct sk_buff *skb = tid_agg_rx->reorder_buf[index]; struct ieee80211_rx_status *status; lockdep_assert_held(&tid_agg_rx->reorder_lock); if (!skb) goto no_frame; /* release the frame from the reorder ring buffer */ tid_agg_rx->stored_mpdu_num--; tid_agg_rx->reorder_buf[index] = NULL; status = IEEE80211_SKB_RXCB(skb); status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE; skb_queue_tail(&local->rx_skb_queue, 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_sub_if_data *sdata, struct tid_ampdu_rx *tid_agg_rx, u16 head_seq_num) { int index; lockdep_assert_held(&tid_agg_rx->reorder_lock); 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(sdata, tid_agg_rx, index); } } /* * 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. * * Callers must hold tid_agg_rx->reorder_lock. */ #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10) static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata, struct tid_ampdu_rx *tid_agg_rx) { int index, j; lockdep_assert_held(&tid_agg_rx->reorder_lock); /* 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) { /* * No buffers ready to be released, but check whether any * frames in the reorder buffer have timed out. */ 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 (skipped && !time_after(jiffies, tid_agg_rx->reorder_time[j] + HT_RX_REORDER_BUF_TIMEOUT)) goto set_release_timer; ht_dbg_ratelimited(sdata, "release an RX reorder frame due to timeout on earlier frames\n"); ieee80211_release_reorder_frame(sdata, tid_agg_rx, j); /* * 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(sdata, tid_agg_rx, index); index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size; } if (tid_agg_rx->stored_mpdu_num) { j = index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size; for (; j != (index - 1) % tid_agg_rx->buf_size; j = (j + 1) % tid_agg_rx->buf_size) { if (tid_agg_rx->reorder_buf[j]) break; } set_release_timer: mod_timer(&tid_agg_rx->reorder_timer, tid_agg_rx->reorder_time[j] + 1 + HT_RX_REORDER_BUF_TIMEOUT); } else { del_timer(&tid_agg_rx->reorder_timer); } } /* * 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_sub_if_data *sdata, struct tid_ampdu_rx *tid_agg_rx, struct sk_buff *skb) { 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; bool ret = true; spin_lock(&tid_agg_rx->reorder_lock); 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); goto out; } /* * 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(sdata, tid_agg_rx, head_seq_num); } /* 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); goto out; } /* * 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 it is first but there's something stored, we may be able * to release frames after this one. */ 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); ret = false; goto out; } /* 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++; ieee80211_sta_reorder_release(sdata, tid_agg_rx); out: spin_unlock(&tid_agg_rx->reorder_lock); return ret; } /* * 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 *skb = rx->skb; struct ieee80211_local *local = rx->local; struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); struct sta_info *sta = rx->sta; struct tid_ampdu_rx *tid_agg_rx; u16 sc; u8 tid, ack_policy; 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; ack_policy = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_ACK_POLICY_MASK; tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); if (!tid_agg_rx) goto dont_reorder; /* qos null data frames are excluded */ if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC))) goto dont_reorder; /* not part of a BA session */ if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK && ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL) goto dont_reorder; /* not actually part of this BA session */ if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) goto dont_reorder; /* new, potentially un-ordered, ampdu frame - process it */ /* reset session timer */ if (tid_agg_rx->timeout) tid_agg_rx->last_rx = jiffies; /* if this mpdu is fragmented - terminate rx aggregation session */ sc = le16_to_cpu(hdr->seq_ctrl); if (sc & IEEE80211_SCTL_FRAG) { skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; skb_queue_tail(&rx->sdata->skb_queue, skb); ieee80211_queue_work(&local->hw, &rx->sdata->work); return; } /* * No locking needed -- we will only ever process one * RX packet at a time, and thus own tid_agg_rx. All * other code manipulating it needs to (and does) make * sure that we cannot get to it any more before doing * anything with it. */ if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb)) return; dont_reorder: skb_queue_tail(&local->rx_skb_queue, 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; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); /* 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->seqno_idx] == hdr->seq_ctrl)) { if (status->rx_flags & IEEE80211_RX_RA_MATCH) { rx->local->dot11FrameDuplicateCount++; rx->sta->num_duplicates++; } return RX_DROP_UNUSABLE; } else rx->sta->last_seq_ctrl[rx->seqno_idx] = 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->sdata->vif.type != NL80211_IFTYPE_WDS && (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) { /* * accept port control frames from the AP even when it's not * yet marked ASSOC to prevent a race where we don't set the * assoc bit quickly enough before it sends the first frame */ if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION && ieee80211_is_data_present(hdr->frame_control)) { unsigned int hdrlen; __be16 ethertype; hdrlen = ieee80211_hdrlen(hdr->frame_control); if (rx->skb->len < hdrlen + 8) return RX_DROP_MONITOR; skb_copy_bits(rx->skb, hdrlen + 6, ðertype, 2); if (ethertype == rx->sdata->control_port_protocol) return RX_CONTINUE; } if (rx->sdata->vif.type == NL80211_IFTYPE_AP && cfg80211_rx_spurious_frame(rx->sdata->dev, hdr->addr2, GFP_ATOMIC)) return RX_DROP_UNUSABLE; 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 *sta_ptk = NULL; int mmie_keyidx = -1; __le16 fc; /* * 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 (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) return RX_CONTINUE; /* start without a key */ rx->key = NULL; if (rx->sta) sta_ptk = rcu_dereference(rx->sta->ptk); fc = hdr->frame_control; if (!ieee80211_has_protected(fc)) mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb); if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) { rx->key = sta_ptk; if ((status->flag & RX_FLAG_DECRYPTED) && (status->flag & RX_FLAG_IV_STRIPPED)) return RX_CONTINUE; /* Skip decryption if the frame is not protected. */ if (!ieee80211_has_protected(fc)) 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 */ if (rx->sta) rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]); if (!rx->key) rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]); } else if (!ieee80211_has_protected(fc)) { /* * 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; struct ieee80211_sub_if_data *sdata = rx->sdata; int i; if (ieee80211_is_mgmt(fc) && is_multicast_ether_addr(hdr->addr1) && (key = rcu_dereference(rx->sdata->default_mgmt_key))) rx->key = key; else { if (rx->sta) { for (i = 0; i < NUM_DEFAULT_KEYS; i++) { key = rcu_dereference(rx->sta->gtk[i]); if (key) break; } } if (!key) { for (i = 0; i < NUM_DEFAULT_KEYS; i++) { key = rcu_dereference(sdata->keys[i]); if (key) break; } } if (key) rx->key = key; } return RX_CONTINUE; } else { u8 keyid; /* * 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(fc); 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 */ skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1); keyidx = keyid >> 6; /* check per-station GTK first, if multicast packet */ if (is_multicast_ether_addr(hdr->addr1) && rx->sta) rx->key = rcu_dereference(rx->sta->gtk[keyidx]); /* if not found, try default key */ if (!rx->key) { 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.cipher != WLAN_CIPHER_SUITE_WEP40 && rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 && !is_multicast_ether_addr(hdr->addr1)) rx->key = NULL; } } if (rx->key) { if (unlikely(rx->key->flags & KEY_FLAG_TAINTED)) return RX_DROP_MONITOR; rx->key->tx_rx_count++; /* TODO: add threshold stuff again */ } else { return RX_DROP_MONITOR; } switch (rx->key->conf.cipher) { case WLAN_CIPHER_SUITE_WEP40: case WLAN_CIPHER_SUITE_WEP104: result = ieee80211_crypto_wep_decrypt(rx); break; case WLAN_CIPHER_SUITE_TKIP: result = ieee80211_crypto_tkip_decrypt(rx); break; case WLAN_CIPHER_SUITE_CCMP: result = ieee80211_crypto_ccmp_decrypt(rx); break; case WLAN_CIPHER_SUITE_AES_CMAC: result = ieee80211_crypto_aes_cmac_decrypt(rx); break; default: /* * We can reach here only with HW-only algorithms * but why didn't it decrypt the frame?! */ return RX_DROP_UNUSABLE; } /* the hdr variable is invalid after the decrypt handlers */ /* 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 sta_ps_start(struct sta_info *sta) { struct ieee80211_sub_if_data *sdata = sta->sdata; struct ieee80211_local *local = sdata->local; struct ps_data *ps; if (sta->sdata->vif.type == NL80211_IFTYPE_AP || sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) ps = &sdata->bss->ps; else return; atomic_inc(&ps->num_sta_ps); set_sta_flag(sta, WLAN_STA_PS_STA); if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS)) drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta); ps_dbg(sdata, "STA %pM aid %d enters power save mode\n", sta->sta.addr, sta->sta.aid); } static void sta_ps_end(struct sta_info *sta) { ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n", sta->sta.addr, sta->sta.aid); if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) { ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n", sta->sta.addr, sta->sta.aid); return; } ieee80211_sta_ps_deliver_wakeup(sta); } int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start) { struct sta_info *sta_inf = container_of(sta, struct sta_info, sta); bool in_ps; WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS)); /* Don't let the same PS state be set twice */ in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA); if ((start && in_ps) || (!start && !in_ps)) return -EINVAL; if (start) sta_ps_start(sta_inf); else sta_ps_end(sta_inf); return 0; } EXPORT_SYMBOL(ieee80211_sta_ps_transition); static ieee80211_rx_result debug_noinline ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx) { struct ieee80211_sub_if_data *sdata = rx->sdata; struct ieee80211_hdr *hdr = (void *)rx->skb->data; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); int tid, ac; if (!rx->sta || !(status->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_CONTINUE; /* * The device handles station powersave, so don't do anything about * uAPSD and PS-Poll frames (the latter shouldn't even come up from * it to mac80211 since they're handled.) */ if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS) return RX_CONTINUE; /* * Don't do anything if the station isn't already asleep. In * the uAPSD case, the station will probably be marked asleep, * in the PS-Poll case the station must be confused ... */ if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA)) return RX_CONTINUE; if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) { if (!test_sta_flag(rx->sta, WLAN_STA_SP)) { if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER)) ieee80211_sta_ps_deliver_poll_response(rx->sta); else set_sta_flag(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; } else if (!ieee80211_has_morefrags(hdr->frame_control) && !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) && ieee80211_has_pm(hdr->frame_control) && (ieee80211_is_data_qos(hdr->frame_control) || ieee80211_is_qos_nullfunc(hdr->frame_control))) { tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; ac = ieee802_1d_to_ac[tid & 7]; /* * If this AC is not trigger-enabled do nothing. * * NB: This could/should check a separate bitmap of trigger- * enabled queues, but for now we only implement uAPSD w/o * TSPEC changes to the ACs, so they're always the same. */ if (!(rx->sta->sta.uapsd_queues & BIT(ac))) return RX_CONTINUE; /* if we are in a service period, do nothing */ if (test_sta_flag(rx->sta, WLAN_STA_SP)) return RX_CONTINUE; if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER)) ieee80211_sta_ps_deliver_uapsd(rx->sta); else set_sta_flag(rx->sta, WLAN_STA_UAPSD); } return RX_CONTINUE; } 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 (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid)) { sta->last_rx = jiffies; if (ieee80211_is_data(hdr->frame_control)) { sta->last_rx_rate_idx = status->rate_idx; sta->last_rx_rate_flag = status->flag; } } } 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 (ieee80211_is_data(hdr->frame_control)) { sta->last_rx_rate_idx = status->rate_idx; sta->last_rx_rate_flag = status->flag; } } if (!(status->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; if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) { sta->last_signal = status->signal; ewma_add(&sta->avg_signal, -status->signal); } /* * Change STA power saving mode only at the end of a frame * exchange sequence. */ if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) && !ieee80211_has_morefrags(hdr->frame_control) && !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) && (rx->sdata->vif.type == NL80211_IFTYPE_AP || rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) { if (test_sta_flag(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)) sta_ps_end(sta); } else { if (ieee80211_has_pm(hdr->frame_control)) 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 send * the event to userspace and for older hostapd drop * the frame to the monitor interface. */ 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))) { if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT)) cfg80211_rx_unexpected_4addr_frame( rx->sdata->dev, sta->sta.addr, GFP_ATOMIC); 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; entry = &sdata->fragments[sdata->fragment_next++]; if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX) sdata->fragment_next = 0; if (!skb_queue_empty(&entry->skb_list)) __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)) || !ether_addr_equal(hdr->addr1, f_hdr->addr1) || !ether_addr_equal(hdr->addr2, f_hdr->addr2)) 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; struct ieee80211_rx_status *status; hdr = (struct ieee80211_hdr *)rx->skb->data; fc = hdr->frame_control; if (ieee80211_is_ctl(fc)) return RX_CONTINUE; sc = le16_to_cpu(hdr->seq_ctrl); frag = sc & IEEE80211_SCTL_FRAG; if (likely((!ieee80211_has_morefrags(fc) && frag == 0) || is_multicast_ether_addr(hdr->addr1))) { /* not fragmented */ goto out; } I802_DEBUG_INC(rx->local->rx_handlers_fragments); if (skb_linearize(rx->skb)) return RX_DROP_UNUSABLE; /* * skb_linearize() might change the skb->data and * previously cached variables (in this case, hdr) need to * be refreshed with the new data. */ hdr = (struct ieee80211_hdr *)rx->skb->data; 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->seqno_idx, &(rx->skb)); if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP && ieee80211_has_protected(fc)) { int queue = rx->security_idx; /* 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[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->seqno_idx, 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; int queue; if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_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; } queue = rx->security_idx; rpn = rx->key->u.ccmp.rx_pn[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 */ status = IEEE80211_SKB_RXCB(rx->skb); status->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 int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx) { if (unlikely(!rx->sta || !test_sta_flag(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; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); __le16 fc = hdr->frame_control; /* * Pass through unencrypted frames if the hardware has * decrypted them already. */ if (status->flag & RX_FLAG_DECRYPTED) return 0; if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) { if (unlikely(!ieee80211_has_protected(fc) && ieee80211_is_unicast_robust_mgmt_frame(rx->skb) && rx->key)) { if (ieee80211_is_deauth(fc)) cfg80211_send_unprot_deauth(rx->sdata->dev, rx->skb->data, rx->skb->len); else if (ieee80211_is_disassoc(fc)) cfg80211_send_unprot_disassoc(rx->sdata->dev, rx->skb->data, rx->skb->len); 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)) { if (ieee80211_is_deauth(fc)) cfg80211_send_unprot_deauth(rx->sdata->dev, rx->skb->data, rx->skb->len); else if (ieee80211_is_disassoc(fc)) cfg80211_send_unprot_disassoc(rx->sdata->dev, rx->skb->data, rx->skb->len); 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, bool *port_control) { struct ieee80211_sub_if_data *sdata = rx->sdata; struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; bool check_port_control = false; struct ethhdr *ehdr; int ret; *port_control = false; if (ieee80211_has_a4(hdr->frame_control) && sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta) return -1; if (sdata->vif.type == NL80211_IFTYPE_STATION && !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) { if (!sdata->u.mgd.use_4addr) return -1; else check_port_control = true; } if (is_multicast_ether_addr(hdr->addr1) && sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) return -1; ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type); if (ret < 0) return ret; ehdr = (struct ethhdr *) rx->skb->data; if (ehdr->h_proto == rx->sdata->control_port_protocol) *port_control = true; else if (check_port_control) return -1; return 0; } /* * 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 == rx->sdata->control_port_protocol && (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) || ether_addr_equal(ehdr->h_dest, pae_group_addr))) 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; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 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) && (status->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_info_ratelimited("%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_receive_skb(skb); } } if (xmit_skb) { /* * Send to wireless media and increase priority by 256 to * keep the received priority instead of reclassifying * the frame (see cfg80211_classify8021d). */ xmit_skb->priority += 256; 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; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); if (unlikely(!ieee80211_is_data(fc))) return RX_CONTINUE; if (unlikely(!ieee80211_is_data_present(fc))) return RX_DROP_MONITOR; if (!(status->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); if (skb_linearize(skb)) return RX_DROP_UNUSABLE; ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr, rx->sdata->vif.type, rx->local->hw.extra_tx_headroom, true); 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 *fwd_hdr, *hdr; struct ieee80211_tx_info *info; struct ieee80211s_hdr *mesh_hdr; struct sk_buff *skb = rx->skb, *fwd_skb; struct ieee80211_local *local = rx->local; struct ieee80211_sub_if_data *sdata = rx->sdata; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; __le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD); u16 q, hdrlen; hdr = (struct ieee80211_hdr *) skb->data; hdrlen = ieee80211_hdrlen(hdr->frame_control); /* make sure fixed part of mesh header is there, also checks skb len */ if (!pskb_may_pull(rx->skb, hdrlen + 6)) return RX_DROP_MONITOR; mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); /* make sure full mesh header is there, also checks skb len */ if (!pskb_may_pull(rx->skb, hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr))) return RX_DROP_MONITOR; /* reload pointers */ hdr = (struct ieee80211_hdr *) skb->data; mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); /* frame is in RMC, don't forward */ if (ieee80211_is_data(hdr->frame_control) && is_multicast_ether_addr(hdr->addr1) && mesh_rmc_check(hdr->addr3, mesh_hdr, rx->sdata)) return RX_DROP_MONITOR; if (!ieee80211_is_data(hdr->frame_control) || !(status->rx_flags & IEEE80211_RX_RA_MATCH)) return RX_CONTINUE; if (!mesh_hdr->ttl) 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 if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) { /* has_a4 already checked in ieee80211_rx_mesh_check */ mpp_addr = hdr->addr4; proxied_addr = mesh_hdr->eaddr2; } else { return RX_DROP_MONITOR; } 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 (!ether_addr_equal(mppath->mpp, mpp_addr)) 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) && ether_addr_equal(sdata->vif.addr, hdr->addr3)) return RX_CONTINUE; q = ieee80211_select_queue_80211(sdata, skb, hdr); if (ieee80211_queue_stopped(&local->hw, q)) { IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion); return RX_DROP_MONITOR; } skb_set_queue_mapping(skb, q); if (!--mesh_hdr->ttl) { IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl); goto out; } if (!ifmsh->mshcfg.dot11MeshForwarding) goto out; fwd_skb = skb_copy(skb, GFP_ATOMIC); if (!fwd_skb) { net_info_ratelimited("%s: failed to clone mesh frame\n", sdata->name); goto out; } fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data; info = IEEE80211_SKB_CB(fwd_skb); memset(info, 0, sizeof(*info)); info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; info->control.vif = &rx->sdata->vif; info->control.jiffies = jiffies; if (is_multicast_ether_addr(fwd_hdr->addr1)) { IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast); memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN); } else if (!mesh_nexthop_lookup(fwd_skb, sdata)) { IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast); } else { /* unable to resolve next hop */ mesh_path_error_tx(ifmsh->mshcfg.element_ttl, fwd_hdr->addr3, 0, reason, fwd_hdr->addr2, sdata); IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route); kfree_skb(fwd_skb); return RX_DROP_MONITOR; } IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames); ieee80211_add_pending_skb(local, fwd_skb); out: 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; bool port_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; /* * Send unexpected-4addr-frame event to hostapd. For older versions, * also drop the frame to cooked monitor interfaces. */ if (ieee80211_has_a4(hdr->frame_control) && sdata->vif.type == NL80211_IFTYPE_AP) { if (rx->sta && !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT)) cfg80211_rx_unexpected_4addr_frame( rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC); return RX_DROP_MONITOR; } err = __ieee80211_data_to_8023(rx, &port_control); if (unlikely(err)) return RX_DROP_UNUSABLE; if (!ieee80211_frame_allowed(rx, fc)) return RX_DROP_MONITOR; if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && unlikely(port_control) && sdata->bss) { sdata = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap); dev = sdata->dev; rx->sdata = sdata; } rx->skb->dev = dev; dev->stats.rx_packets++; dev->stats.rx_bytes += rx->skb->len; if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 && !is_multicast_ether_addr( ((struct ethhdr *)rx->skb->data)->h_dest) && (!local->scanning && !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) { 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 *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)) { struct { __le16 control, start_seq_num; } __packed bar_data; if (!rx->sta) return RX_DROP_MONITOR; if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control), &bar_data, sizeof(bar_data))) return RX_DROP_MONITOR; tid = le16_to_cpu(bar_data.control) >> 12; tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]); if (!tid_agg_rx) return RX_DROP_MONITOR; start_seq_num = le16_to_cpu(bar_data.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)); spin_lock(&tid_agg_rx->reorder_lock); /* release stored frames up to start of BAR */ ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx, start_seq_num); spin_unlock(&tid_agg_rx->reorder_lock); kfree_skb(skb); return RX_QUEUED; } /* * After this point, we only want management frames, * so we can drop all remaining control frames to * cooked monitor interfaces. */ return RX_DROP_MONITOR; } 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 (!ether_addr_equal(mgmt->da, sdata->vif.addr)) { /* Not to own unicast address */ return; } if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) || !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) { /* 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_mgmt_check(struct ieee80211_rx_data *rx) { struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); /* * From here on, look only at management frames. * Data and control frames are already handled, * and unknown (reserved) frames are useless. */ if (rx->skb->len < 24) return RX_DROP_MONITOR; if (!ieee80211_is_mgmt(mgmt->frame_control)) return RX_DROP_MONITOR; if (rx->sdata->vif.type == NL80211_IFTYPE_AP && ieee80211_is_beacon(mgmt->frame_control) && !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) { int sig = 0; if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM) sig = status->signal; cfg80211_report_obss_beacon(rx->local->hw.wiphy, rx->skb->data, rx->skb->len, status->freq, sig); rx->flags |= IEEE80211_RX_BEACON_REPORTED; } if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) return RX_DROP_MONITOR; if (ieee80211_drop_unencrypted_mgmt(rx)) return RX_DROP_UNUSABLE; return RX_CONTINUE; } 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 ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 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 (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) return RX_DROP_UNUSABLE; switch (mgmt->u.action.category) { case WLAN_CATEGORY_HT: /* reject HT action frames from stations not supporting HT */ if (!rx->sta->sta.ht_cap.ht_supported) goto invalid; if (sdata->vif.type != NL80211_IFTYPE_STATION && sdata->vif.type != NL80211_IFTYPE_MESH_POINT && sdata->vif.type != NL80211_IFTYPE_AP_VLAN && sdata->vif.type != NL80211_IFTYPE_AP && sdata->vif.type != NL80211_IFTYPE_ADHOC) break; /* verify action & smps_control are present */ if (len < IEEE80211_MIN_ACTION_SIZE + 2) goto invalid; switch (mgmt->u.action.u.ht_smps.action) { case WLAN_HT_ACTION_SMPS: { struct ieee80211_supported_band *sband; u8 smps; /* convert to HT capability */ switch (mgmt->u.action.u.ht_smps.smps_control) { case WLAN_HT_SMPS_CONTROL_DISABLED: smps = WLAN_HT_CAP_SM_PS_DISABLED; break; case WLAN_HT_SMPS_CONTROL_STATIC: smps = WLAN_HT_CAP_SM_PS_STATIC; break; case WLAN_HT_SMPS_CONTROL_DYNAMIC: smps = WLAN_HT_CAP_SM_PS_DYNAMIC; break; default: goto invalid; } smps <<= IEEE80211_HT_CAP_SM_PS_SHIFT; /* if no change do nothing */ if ((rx->sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SM_PS) == smps) goto handled; rx->sta->sta.ht_cap.cap &= ~IEEE80211_HT_CAP_SM_PS; rx->sta->sta.ht_cap.cap |= smps; sband = rx->local->hw.wiphy->bands[status->band]; rate_control_rate_update(local, sband, rx->sta, IEEE80211_RC_SMPS_CHANGED); goto handled; } default: goto invalid; } break; case WLAN_CATEGORY_BACK: if (sdata->vif.type != NL80211_IFTYPE_STATION && sdata->vif.type != NL80211_IFTYPE_MESH_POINT && sdata->vif.type != NL80211_IFTYPE_AP_VLAN && sdata->vif.type != NL80211_IFTYPE_AP && sdata->vif.type != NL80211_IFTYPE_ADHOC) 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))) goto invalid; break; case WLAN_ACTION_ADDBA_RESP: if (len < (IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.addba_resp))) goto invalid; break; case WLAN_ACTION_DELBA: if (len < (IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.delba))) goto invalid; break; default: goto invalid; } goto queue; case WLAN_CATEGORY_SPECTRUM_MGMT: if (status->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 (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) break; goto queue; } 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; case WLAN_CATEGORY_SELF_PROTECTED: if (len < (IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.self_prot.action_code))) break; switch (mgmt->u.action.u.self_prot.action_code) { case WLAN_SP_MESH_PEERING_OPEN: case WLAN_SP_MESH_PEERING_CLOSE: case WLAN_SP_MESH_PEERING_CONFIRM: if (!ieee80211_vif_is_mesh(&sdata->vif)) goto invalid; if (sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE) /* userspace handles this frame */ break; goto queue; case WLAN_SP_MGK_INFORM: case WLAN_SP_MGK_ACK: if (!ieee80211_vif_is_mesh(&sdata->vif)) goto invalid; break; } break; case WLAN_CATEGORY_MESH_ACTION: if (len < (IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.mesh_action.action_code))) break; if (!ieee80211_vif_is_mesh(&sdata->vif)) break; if (mesh_action_is_path_sel(mgmt) && !mesh_path_sel_is_hwmp(sdata)) break; goto queue; } return RX_CONTINUE; invalid: status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM; /* will return in the next handlers */ return RX_CONTINUE; handled: if (rx->sta) rx->sta->rx_packets++; dev_kfree_skb(rx->skb); return RX_QUEUED; queue: rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; skb_queue_tail(&sdata->skb_queue, rx->skb); ieee80211_queue_work(&local->hw, &sdata->work); if (rx->sta) rx->sta->rx_packets++; return RX_QUEUED; } static ieee80211_rx_result debug_noinline ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx) { struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); int sig = 0; /* skip known-bad action frames and return them in the next handler */ if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) return RX_CONTINUE; /* * 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. */ if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM) sig = status->signal; if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig, rx->skb->data, rx->skb->len, GFP_ATOMIC)) { if (rx->sta) rx->sta->rx_packets++; dev_kfree_skb(rx->skb); return RX_QUEUED; } return RX_CONTINUE; } static ieee80211_rx_result debug_noinline ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx) { struct ieee80211_local *local = rx->local; struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; struct sk_buff *nskb; struct ieee80211_sub_if_data *sdata = rx->sdata; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); if (!ieee80211_is_action(mgmt->frame_control)) return RX_CONTINUE; /* * 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 * 802.11-2012 9.24.4. * Newer versions of hostapd shall also use the management frame * registration mechanisms, but older ones still use cooked * monitor interfaces so push all frames there. */ if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) && (sdata->vif.type == NL80211_IFTYPE_AP || sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) return RX_DROP_MONITOR; if (is_multicast_ether_addr(mgmt->da)) return RX_DROP_MONITOR; /* 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 *nmgmt = (void *)nskb->data; nmgmt->u.action.category |= 0x80; memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN); memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN); memset(nskb->cb, 0, sizeof(nskb->cb)); ieee80211_tx_skb(rx->sdata, nskb); } 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; struct ieee80211_mgmt *mgmt = (void *)rx->skb->data; __le16 stype; stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE); if (!ieee80211_vif_is_mesh(&sdata->vif) && sdata->vif.type != NL80211_IFTYPE_ADHOC && sdata->vif.type != NL80211_IFTYPE_STATION) return RX_DROP_MONITOR; switch (stype) { case cpu_to_le16(IEEE80211_STYPE_AUTH): case cpu_to_le16(IEEE80211_STYPE_BEACON): case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP): /* process for all: mesh, mlme, ibss */ break; case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP): case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP): case cpu_to_le16(IEEE80211_STYPE_DEAUTH): case cpu_to_le16(IEEE80211_STYPE_DISASSOC): if (is_multicast_ether_addr(mgmt->da) && !is_broadcast_ether_addr(mgmt->da)) return RX_DROP_MONITOR; /* process only for station */ if (sdata->vif.type != NL80211_IFTYPE_STATION) return RX_DROP_MONITOR; break; case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ): /* process only for ibss */ if (sdata->vif.type != NL80211_IFTYPE_ADHOC) return RX_DROP_MONITOR; break; default: return RX_DROP_MONITOR; } /* queue up frame and kick off work to process it */ rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; skb_queue_tail(&sdata->skb_queue, rx->skb); ieee80211_queue_work(&rx->local->hw, &sdata->work); if (rx->sta) rx->sta->rx_packets++; return RX_QUEUED; } /* 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 sk_buff *skb = rx->skb, *skb2; struct net_device *prev_dev = NULL; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); int needed_headroom; /* * If cooked monitor has been processed already, then * don't do it again. If not, set the flag. */ if (rx->flags & IEEE80211_RX_CMNTR) goto out_free_skb; rx->flags |= IEEE80211_RX_CMNTR; /* If there are no cooked monitor interfaces, just free the SKB */ if (!local->cooked_mntrs) goto out_free_skb; /* room for the radiotap header based on driver features */ needed_headroom = ieee80211_rx_radiotap_space(local, status); if (skb_headroom(skb) < needed_headroom && pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) goto out_free_skb; /* prepend radiotap information */ ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom, false); 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_receive_skb(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_receive_skb(skb); return; } out_free_skb: dev_kfree_skb(skb); } static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx, ieee80211_rx_result res) { switch (res) { case RX_DROP_MONITOR: I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop); if (rx->sta) rx->sta->rx_dropped++; /* fall through */ case RX_CONTINUE: { struct ieee80211_rate *rate = NULL; struct ieee80211_supported_band *sband; struct ieee80211_rx_status *status; status = IEEE80211_SKB_RXCB((rx->skb)); sband = rx->local->hw.wiphy->bands[status->band]; if (!(status->flag & RX_FLAG_HT)) rate = &sband->bitrates[status->rate_idx]; ieee80211_rx_cooked_monitor(rx, rate); break; } case RX_DROP_UNUSABLE: I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop); if (rx->sta) rx->sta->rx_dropped++; dev_kfree_skb(rx->skb); break; case RX_QUEUED: I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued); break; } } static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx) { ieee80211_rx_result res = RX_DROP_MONITOR; struct sk_buff *skb; #define CALL_RXH(rxh) \ do { \ res = rxh(rx); \ if (res != RX_CONTINUE) \ goto rxh_next; \ } while (0); spin_lock(&rx->local->rx_skb_queue.lock); if (rx->local->running_rx_handler) goto unlock; rx->local->running_rx_handler = true; while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) { spin_unlock(&rx->local->rx_skb_queue.lock); /* * 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_uapsd_and_pspoll) CALL_RXH(ieee80211_rx_h_sta_process) CALL_RXH(ieee80211_rx_h_defragment) CALL_RXH(ieee80211_rx_h_michael_mic_verify) /* must be after MMIC verify so header is counted in MPDU mic */ #ifdef CONFIG_MAC80211_MESH if (ieee80211_vif_is_mesh(&rx->sdata->vif)) CALL_RXH(ieee80211_rx_h_mesh_fwding); #endif CALL_RXH(ieee80211_rx_h_amsdu) CALL_RXH(ieee80211_rx_h_data) CALL_RXH(ieee80211_rx_h_ctrl); CALL_RXH(ieee80211_rx_h_mgmt_check) CALL_RXH(ieee80211_rx_h_action) CALL_RXH(ieee80211_rx_h_userspace_mgmt) CALL_RXH(ieee80211_rx_h_action_return) CALL_RXH(ieee80211_rx_h_mgmt) rxh_next: ieee80211_rx_handlers_result(rx, res); spin_lock(&rx->local->rx_skb_queue.lock); #undef CALL_RXH } rx->local->running_rx_handler = false; unlock: spin_unlock(&rx->local->rx_skb_queue.lock); } static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx) { ieee80211_rx_result res = RX_DROP_MONITOR; #define CALL_RXH(rxh) \ do { \ res = rxh(rx); \ if (res != RX_CONTINUE) \ goto rxh_next; \ } while (0); CALL_RXH(ieee80211_rx_h_check) ieee80211_rx_reorder_ampdu(rx); ieee80211_rx_handlers(rx); return; rxh_next: ieee80211_rx_handlers_result(rx, res); #undef CALL_RXH } /* * This function makes calls into the RX path, therefore * it has to be invoked under RCU read lock. */ void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid) { struct ieee80211_rx_data rx = { .sta = sta, .sdata = sta->sdata, .local = sta->local, /* This is OK -- must be QoS data frame */ .security_idx = tid, .seqno_idx = tid, .flags = 0, }; struct tid_ampdu_rx *tid_agg_rx; tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); if (!tid_agg_rx) return; spin_lock(&tid_agg_rx->reorder_lock); ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx); spin_unlock(&tid_agg_rx->reorder_lock); ieee80211_rx_handlers(&rx); } /* main receive path */ static int prepare_for_handlers(struct ieee80211_rx_data *rx, struct ieee80211_hdr *hdr) { struct ieee80211_sub_if_data *sdata = rx->sdata; 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 && !ether_addr_equal(sdata->vif.addr, hdr->addr1)) { if (!(sdata->dev->flags & IFF_PROMISC) || sdata->u.mgd.use_4addr) return 0; status->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)) { return 0; } else if (!multicast && !ether_addr_equal(sdata->vif.addr, hdr->addr1)) { if (!(sdata->dev->flags & IFF_PROMISC)) return 0; status->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; ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2, BIT(rate_idx)); } break; case NL80211_IFTYPE_MESH_POINT: if (!multicast && !ether_addr_equal(sdata->vif.addr, hdr->addr1)) { if (!(sdata->dev->flags & IFF_PROMISC)) return 0; status->rx_flags &= ~IEEE80211_RX_RA_MATCH; } break; case NL80211_IFTYPE_AP_VLAN: case NL80211_IFTYPE_AP: if (!bssid) { if (!ether_addr_equal(sdata->vif.addr, hdr->addr1)) return 0; } else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) { /* * Accept public action frames even when the * BSSID doesn't match, this is used for P2P * and location updates. Note that mac80211 * itself never looks at these frames. */ if (ieee80211_is_public_action(hdr, skb->len)) return 1; if (!ieee80211_is_beacon(hdr->frame_control)) return 0; status->rx_flags &= ~IEEE80211_RX_RA_MATCH; } break; case NL80211_IFTYPE_WDS: if (bssid || !ieee80211_is_data(hdr->frame_control)) return 0; if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2)) return 0; break; case NL80211_IFTYPE_P2P_DEVICE: if (!ieee80211_is_public_action(hdr, skb->len) && !ieee80211_is_probe_req(hdr->frame_control) && !ieee80211_is_probe_resp(hdr->frame_control) && !ieee80211_is_beacon(hdr->frame_control)) return 0; if (!ether_addr_equal(sdata->vif.addr, hdr->addr1)) status->rx_flags &= ~IEEE80211_RX_RA_MATCH; break; default: /* should never get here */ WARN_ON_ONCE(1); break; } return 1; } /* * This function returns whether or not the SKB * was destined for RX processing or not, which, * if consume is true, is equivalent to whether * or not the skb was consumed. */ static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx, struct sk_buff *skb, bool consume) { struct ieee80211_local *local = rx->local; struct ieee80211_sub_if_data *sdata = rx->sdata; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); struct ieee80211_hdr *hdr = (void *)skb->data; int prepares; rx->skb = skb; status->rx_flags |= IEEE80211_RX_RA_MATCH; prepares = prepare_for_handlers(rx, hdr); if (!prepares) return false; if (!consume) { skb = skb_copy(skb, GFP_ATOMIC); if (!skb) { if (net_ratelimit()) wiphy_debug(local->hw.wiphy, "failed to copy skb for %s\n", sdata->name); return true; } rx->skb = skb; } ieee80211_invoke_rx_handlers(rx); return true; } /* * 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_local *local = hw_to_local(hw); struct ieee80211_sub_if_data *sdata; struct ieee80211_hdr *hdr; __le16 fc; struct ieee80211_rx_data rx; struct ieee80211_sub_if_data *prev; struct sta_info *sta, *tmp, *prev_sta; int err = 0; fc = ((struct ieee80211_hdr *)skb->data)->frame_control; memset(&rx, 0, sizeof(rx)); rx.skb = skb; rx.local = local; if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc)) local->dot11ReceivedFragmentCount++; if (ieee80211_is_mgmt(fc)) { /* drop frame if too short for header */ if (skb->len < ieee80211_hdrlen(fc)) err = -ENOBUFS; else err = skb_linearize(skb); } else { err = !pskb_may_pull(skb, ieee80211_hdrlen(fc)); } if (err) { dev_kfree_skb(skb); return; } hdr = (struct ieee80211_hdr *)skb->data; ieee80211_parse_qos(&rx); ieee80211_verify_alignment(&rx); if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) || ieee80211_is_beacon(hdr->frame_control))) ieee80211_scan_rx(local, skb); if (ieee80211_is_data(fc)) { prev_sta = NULL; for_each_sta_info(local, hdr->addr2, sta, tmp) { if (!prev_sta) { prev_sta = sta; continue; } rx.sta = prev_sta; rx.sdata = prev_sta->sdata; ieee80211_prepare_and_rx_handle(&rx, skb, false); prev_sta = sta; } if (prev_sta) { rx.sta = prev_sta; rx.sdata = prev_sta->sdata; if (ieee80211_prepare_and_rx_handle(&rx, skb, true)) return; goto out; } } prev = NULL; 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.sdata = prev; ieee80211_prepare_and_rx_handle(&rx, skb, false); prev = sdata; } if (prev) { rx.sta = sta_info_get_bss(prev, hdr->addr2); rx.sdata = prev; if (ieee80211_prepare_and_rx_handle(&rx, skb, true)) return; } out: 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 >= 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; /* We might be during a HW reconfig, prevent Rx for the same reason */ if (unlikely(local->in_reconfig)) 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 (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) { /* * Validate the rate, unless a PLCP error means that * we probably can't have a valid rate here anyway. */ 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 > 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 >= sband->n_bitrates)) goto drop; rate = &sband->bitrates[status->rate_idx]; } } status->rx_flags = 0; /* * 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_tpt_led_trig_rx(local, ((struct ieee80211_hdr *)skb->data)->frame_control, skb->len); __ieee80211_rx_handle_packet(hw, skb); 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);