/* * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2005-2006, Devicescape Software, Inc. * Copyright 2006-2007 Jiri Benc * Copyright 2007 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. * * * Transmit and frame generation functions. */ #include #include #include #include #include #include #include #include #include #include #include #include "ieee80211_i.h" #include "led.h" #include "mesh.h" #include "wep.h" #include "wpa.h" #include "wme.h" #include "rate.h" #define IEEE80211_TX_OK 0 #define IEEE80211_TX_AGAIN 1 #define IEEE80211_TX_FRAG_AGAIN 2 /* misc utils */ static inline void ieee80211_include_sequence(struct ieee80211_sub_if_data *sdata, struct ieee80211_hdr *hdr) { /* Set the sequence number for this frame. */ hdr->seq_ctrl = cpu_to_le16(sdata->sequence); /* Increase the sequence number. */ sdata->sequence = (sdata->sequence + 0x10) & IEEE80211_SCTL_SEQ; } #ifdef CONFIG_MAC80211_LOWTX_FRAME_DUMP static void ieee80211_dump_frame(const char *ifname, const char *title, const struct sk_buff *skb) { const struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; u16 fc; int hdrlen; DECLARE_MAC_BUF(mac); printk(KERN_DEBUG "%s: %s (len=%d)", ifname, title, skb->len); if (skb->len < 4) { printk("\n"); return; } fc = le16_to_cpu(hdr->frame_control); hdrlen = ieee80211_get_hdrlen(fc); if (hdrlen > skb->len) hdrlen = skb->len; if (hdrlen >= 4) printk(" FC=0x%04x DUR=0x%04x", fc, le16_to_cpu(hdr->duration_id)); if (hdrlen >= 10) printk(" A1=%s", print_mac(mac, hdr->addr1)); if (hdrlen >= 16) printk(" A2=%s", print_mac(mac, hdr->addr2)); if (hdrlen >= 24) printk(" A3=%s", print_mac(mac, hdr->addr3)); if (hdrlen >= 30) printk(" A4=%s", print_mac(mac, hdr->addr4)); printk("\n"); } #else /* CONFIG_MAC80211_LOWTX_FRAME_DUMP */ static inline void ieee80211_dump_frame(const char *ifname, const char *title, struct sk_buff *skb) { } #endif /* CONFIG_MAC80211_LOWTX_FRAME_DUMP */ static u16 ieee80211_duration(struct ieee80211_tx_data *tx, int group_addr, int next_frag_len) { int rate, mrate, erp, dur, i; struct ieee80211_rate *txrate; struct ieee80211_local *local = tx->local; struct ieee80211_supported_band *sband; sband = local->hw.wiphy->bands[tx->channel->band]; txrate = &sband->bitrates[tx->rate_idx]; erp = 0; if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE) erp = txrate->flags & IEEE80211_RATE_ERP_G; /* * data and mgmt (except PS Poll): * - during CFP: 32768 * - during contention period: * if addr1 is group address: 0 * if more fragments = 0 and addr1 is individual address: time to * transmit one ACK plus SIFS * if more fragments = 1 and addr1 is individual address: time to * transmit next fragment plus 2 x ACK plus 3 x SIFS * * IEEE 802.11, 9.6: * - control response frame (CTS or ACK) shall be transmitted using the * same rate as the immediately previous frame in the frame exchange * sequence, if this rate belongs to the PHY mandatory rates, or else * at the highest possible rate belonging to the PHY rates in the * BSSBasicRateSet */ if ((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL) { /* TODO: These control frames are not currently sent by * 80211.o, but should they be implemented, this function * needs to be updated to support duration field calculation. * * RTS: time needed to transmit pending data/mgmt frame plus * one CTS frame plus one ACK frame plus 3 x SIFS * CTS: duration of immediately previous RTS minus time * required to transmit CTS and its SIFS * ACK: 0 if immediately previous directed data/mgmt had * more=0, with more=1 duration in ACK frame is duration * from previous frame minus time needed to transmit ACK * and its SIFS * PS Poll: BIT(15) | BIT(14) | aid */ return 0; } /* data/mgmt */ if (0 /* FIX: data/mgmt during CFP */) return 32768; if (group_addr) /* Group address as the destination - no ACK */ return 0; /* Individual destination address: * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes) * CTS and ACK frames shall be transmitted using the highest rate in * basic rate set that is less than or equal to the rate of the * immediately previous frame and that is using the same modulation * (CCK or OFDM). If no basic rate set matches with these requirements, * the highest mandatory rate of the PHY that is less than or equal to * the rate of the previous frame is used. * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps */ rate = -1; /* use lowest available if everything fails */ mrate = sband->bitrates[0].bitrate; for (i = 0; i < sband->n_bitrates; i++) { struct ieee80211_rate *r = &sband->bitrates[i]; if (r->bitrate > txrate->bitrate) break; if (tx->sdata->basic_rates & BIT(i)) rate = r->bitrate; switch (sband->band) { case IEEE80211_BAND_2GHZ: { u32 flag; if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE) flag = IEEE80211_RATE_MANDATORY_G; else flag = IEEE80211_RATE_MANDATORY_B; if (r->flags & flag) mrate = r->bitrate; break; } case IEEE80211_BAND_5GHZ: if (r->flags & IEEE80211_RATE_MANDATORY_A) mrate = r->bitrate; break; case IEEE80211_NUM_BANDS: WARN_ON(1); break; } } if (rate == -1) { /* No matching basic rate found; use highest suitable mandatory * PHY rate */ rate = mrate; } /* Time needed to transmit ACK * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up * to closest integer */ dur = ieee80211_frame_duration(local, 10, rate, erp, tx->sdata->bss_conf.use_short_preamble); if (next_frag_len) { /* Frame is fragmented: duration increases with time needed to * transmit next fragment plus ACK and 2 x SIFS. */ dur *= 2; /* ACK + SIFS */ /* next fragment */ dur += ieee80211_frame_duration(local, next_frag_len, txrate->bitrate, erp, tx->sdata->bss_conf.use_short_preamble); } return dur; } static int inline is_ieee80211_device(struct net_device *dev, struct net_device *master) { return (wdev_priv(dev->ieee80211_ptr) == wdev_priv(master->ieee80211_ptr)); } /* tx handlers */ static ieee80211_tx_result ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx) { #ifdef CONFIG_MAC80211_VERBOSE_DEBUG struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); u32 sta_flags; if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) return TX_CONTINUE; if (unlikely(tx->local->sta_sw_scanning) && ((tx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT || (tx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PROBE_REQ)) return TX_DROP; if (tx->sdata->vif.type == IEEE80211_IF_TYPE_MESH_POINT) return TX_CONTINUE; if (tx->flags & IEEE80211_TX_PS_BUFFERED) return TX_CONTINUE; sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0; if (likely(tx->flags & IEEE80211_TX_UNICAST)) { if (unlikely(!(sta_flags & WLAN_STA_ASSOC) && tx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS && (tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)) { #ifdef CONFIG_MAC80211_VERBOSE_DEBUG DECLARE_MAC_BUF(mac); printk(KERN_DEBUG "%s: dropped data frame to not " "associated station %s\n", tx->dev->name, print_mac(mac, hdr->addr1)); #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc); return TX_DROP; } } else { if (unlikely((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA && tx->local->num_sta == 0 && tx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS)) { /* * No associated STAs - no need to send multicast * frames. */ return TX_DROP; } return TX_CONTINUE; } return TX_CONTINUE; } static ieee80211_tx_result ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; if (ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control)) >= 24) ieee80211_include_sequence(tx->sdata, hdr); return TX_CONTINUE; } /* This function is called whenever the AP is about to exceed the maximum limit * of buffered frames for power saving STAs. This situation should not really * happen often during normal operation, so dropping the oldest buffered packet * from each queue should be OK to make some room for new frames. */ static void purge_old_ps_buffers(struct ieee80211_local *local) { int total = 0, purged = 0; struct sk_buff *skb; struct ieee80211_sub_if_data *sdata; struct sta_info *sta; /* * virtual interfaces are protected by RCU */ rcu_read_lock(); list_for_each_entry_rcu(sdata, &local->interfaces, list) { struct ieee80211_if_ap *ap; if (sdata->dev == local->mdev || sdata->vif.type != IEEE80211_IF_TYPE_AP) continue; ap = &sdata->u.ap; skb = skb_dequeue(&ap->ps_bc_buf); if (skb) { purged++; dev_kfree_skb(skb); } total += skb_queue_len(&ap->ps_bc_buf); } list_for_each_entry_rcu(sta, &local->sta_list, list) { skb = skb_dequeue(&sta->ps_tx_buf); if (skb) { purged++; dev_kfree_skb(skb); } total += skb_queue_len(&sta->ps_tx_buf); } rcu_read_unlock(); local->total_ps_buffered = total; printk(KERN_DEBUG "%s: PS buffers full - purged %d frames\n", wiphy_name(local->hw.wiphy), purged); } static ieee80211_tx_result ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx) { struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); /* * broadcast/multicast frame * * If any of the associated stations is in power save mode, * the frame is buffered to be sent after DTIM beacon frame. * This is done either by the hardware or us. */ /* not AP/IBSS or ordered frame */ if (!tx->sdata->bss || (tx->fc & IEEE80211_FCTL_ORDER)) return TX_CONTINUE; /* no stations in PS mode */ if (!atomic_read(&tx->sdata->bss->num_sta_ps)) return TX_CONTINUE; /* buffered in mac80211 */ if (tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING) { if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER) purge_old_ps_buffers(tx->local); if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= AP_MAX_BC_BUFFER) { if (net_ratelimit()) { printk(KERN_DEBUG "%s: BC TX buffer full - " "dropping the oldest frame\n", tx->dev->name); } dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf)); } else tx->local->total_ps_buffered++; skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb); return TX_QUEUED; } /* buffered in hardware */ info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM; return TX_CONTINUE; } static ieee80211_tx_result ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx) { struct sta_info *sta = tx->sta; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); u32 staflags; DECLARE_MAC_BUF(mac); if (unlikely(!sta || ((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT && (tx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PROBE_RESP))) return TX_CONTINUE; staflags = get_sta_flags(sta); if (unlikely((staflags & WLAN_STA_PS) && !(staflags & WLAN_STA_PSPOLL))) { #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG printk(KERN_DEBUG "STA %s aid %d: PS buffer (entries " "before %d)\n", print_mac(mac, sta->addr), sta->aid, skb_queue_len(&sta->ps_tx_buf)); #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER) purge_old_ps_buffers(tx->local); if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) { struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf); if (net_ratelimit()) { printk(KERN_DEBUG "%s: STA %s TX " "buffer full - dropping oldest frame\n", tx->dev->name, print_mac(mac, sta->addr)); } dev_kfree_skb(old); } else tx->local->total_ps_buffered++; /* Queue frame to be sent after STA sends an PS Poll frame */ if (skb_queue_empty(&sta->ps_tx_buf)) sta_info_set_tim_bit(sta); info->control.jiffies = jiffies; skb_queue_tail(&sta->ps_tx_buf, tx->skb); return TX_QUEUED; } #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG else if (unlikely(test_sta_flags(sta, WLAN_STA_PS))) { printk(KERN_DEBUG "%s: STA %s in PS mode, but pspoll " "set -> send frame\n", tx->dev->name, print_mac(mac, sta->addr)); } #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ clear_sta_flags(sta, WLAN_STA_PSPOLL); return TX_CONTINUE; } static ieee80211_tx_result ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx) { if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED)) return TX_CONTINUE; if (tx->flags & IEEE80211_TX_UNICAST) return ieee80211_tx_h_unicast_ps_buf(tx); else return ieee80211_tx_h_multicast_ps_buf(tx); } static ieee80211_tx_result ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx) { struct ieee80211_key *key; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); u16 fc = tx->fc; if (unlikely(info->flags & IEEE80211_TX_CTL_DO_NOT_ENCRYPT)) tx->key = NULL; else if (tx->sta && (key = rcu_dereference(tx->sta->key))) tx->key = key; else if ((key = rcu_dereference(tx->sdata->default_key))) tx->key = key; else if (tx->sdata->drop_unencrypted && !(info->flags & IEEE80211_TX_CTL_EAPOL_FRAME) && !(info->flags & IEEE80211_TX_CTL_INJECTED)) { I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted); return TX_DROP; } else tx->key = NULL; if (tx->key) { u16 ftype, stype; tx->key->tx_rx_count++; /* TODO: add threshold stuff again */ switch (tx->key->conf.alg) { case ALG_WEP: ftype = fc & IEEE80211_FCTL_FTYPE; stype = fc & IEEE80211_FCTL_STYPE; if (ftype == IEEE80211_FTYPE_MGMT && stype == IEEE80211_STYPE_AUTH) break; case ALG_TKIP: case ALG_CCMP: if (!WLAN_FC_DATA_PRESENT(fc)) tx->key = NULL; break; } } if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) info->flags |= IEEE80211_TX_CTL_DO_NOT_ENCRYPT; return TX_CONTINUE; } static ieee80211_tx_result ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx) { struct rate_selection rsel; struct ieee80211_supported_band *sband; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); sband = tx->local->hw.wiphy->bands[tx->channel->band]; if (likely(tx->rate_idx < 0)) { rate_control_get_rate(tx->dev, sband, tx->skb, &rsel); tx->rate_idx = rsel.rate_idx; if (unlikely(rsel.probe_idx >= 0)) { info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE; tx->flags |= IEEE80211_TX_PROBE_LAST_FRAG; info->control.alt_retry_rate_idx = tx->rate_idx; tx->rate_idx = rsel.probe_idx; } else info->control.alt_retry_rate_idx = -1; if (unlikely(tx->rate_idx < 0)) return TX_DROP; } else info->control.alt_retry_rate_idx = -1; if (tx->sdata->bss_conf.use_cts_prot && (tx->flags & IEEE80211_TX_FRAGMENTED) && (rsel.nonerp_idx >= 0)) { tx->last_frag_rate_idx = tx->rate_idx; if (rsel.probe_idx >= 0) tx->flags &= ~IEEE80211_TX_PROBE_LAST_FRAG; else tx->flags |= IEEE80211_TX_PROBE_LAST_FRAG; tx->rate_idx = rsel.nonerp_idx; info->tx_rate_idx = rsel.nonerp_idx; info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE; } else { tx->last_frag_rate_idx = tx->rate_idx; info->tx_rate_idx = tx->rate_idx; } info->tx_rate_idx = tx->rate_idx; return TX_CONTINUE; } static ieee80211_tx_result ieee80211_tx_h_misc(struct ieee80211_tx_data *tx) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data; u16 fc = le16_to_cpu(hdr->frame_control); u16 dur; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); struct ieee80211_supported_band *sband; sband = tx->local->hw.wiphy->bands[tx->channel->band]; if (tx->sta) info->control.aid = tx->sta->aid; if (!info->control.retry_limit) { if (!is_multicast_ether_addr(hdr->addr1)) { int len = min_t(int, tx->skb->len + FCS_LEN, tx->local->fragmentation_threshold); if (len > tx->local->rts_threshold && tx->local->rts_threshold < IEEE80211_MAX_RTS_THRESHOLD) { info->flags |= IEEE80211_TX_CTL_USE_RTS_CTS; info->flags |= IEEE80211_TX_CTL_LONG_RETRY_LIMIT; info->control.retry_limit = tx->local->long_retry_limit; } else { info->control.retry_limit = tx->local->short_retry_limit; } } else { info->control.retry_limit = 1; } } if (tx->flags & IEEE80211_TX_FRAGMENTED) { /* Do not use multiple retry rates when sending fragmented * frames. * TODO: The last fragment could still use multiple retry * rates. */ info->control.alt_retry_rate_idx = -1; } /* Use CTS protection for unicast frames sent using extended rates if * there are associated non-ERP stations and RTS/CTS is not configured * for the frame. */ if ((tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE) && (sband->bitrates[tx->rate_idx].flags & IEEE80211_RATE_ERP_G) && (tx->flags & IEEE80211_TX_UNICAST) && tx->sdata->bss_conf.use_cts_prot && !(info->flags & IEEE80211_TX_CTL_USE_RTS_CTS)) info->flags |= IEEE80211_TX_CTL_USE_CTS_PROTECT; /* Transmit data frames using short preambles if the driver supports * short preambles at the selected rate and short preambles are * available on the network at the current point in time. */ if (((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) && (sband->bitrates[tx->rate_idx].flags & IEEE80211_RATE_SHORT_PREAMBLE) && tx->sdata->bss_conf.use_short_preamble && (!tx->sta || test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE))) { info->flags |= IEEE80211_TX_CTL_SHORT_PREAMBLE; } /* Setup duration field for the first fragment of the frame. Duration * for remaining fragments will be updated when they are being sent * to low-level driver in ieee80211_tx(). */ dur = ieee80211_duration(tx, is_multicast_ether_addr(hdr->addr1), (tx->flags & IEEE80211_TX_FRAGMENTED) ? tx->extra_frag[0]->len : 0); hdr->duration_id = cpu_to_le16(dur); if ((info->flags & IEEE80211_TX_CTL_USE_RTS_CTS) || (info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)) { struct ieee80211_rate *rate; s8 baserate = -1; int idx; /* Do not use multiple retry rates when using RTS/CTS */ info->control.alt_retry_rate_idx = -1; /* Use min(data rate, max base rate) as CTS/RTS rate */ rate = &sband->bitrates[tx->rate_idx]; for (idx = 0; idx < sband->n_bitrates; idx++) { if (sband->bitrates[idx].bitrate > rate->bitrate) continue; if (tx->sdata->basic_rates & BIT(idx) && (baserate < 0 || (sband->bitrates[baserate].bitrate < sband->bitrates[idx].bitrate))) baserate = idx; } if (baserate >= 0) info->control.rts_cts_rate_idx = baserate; else info->control.rts_cts_rate_idx = 0; } if (tx->sta) info->control.aid = tx->sta->aid; return TX_CONTINUE; } static ieee80211_tx_result ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data; size_t hdrlen, per_fragm, num_fragm, payload_len, left; struct sk_buff **frags, *first, *frag; int i; u16 seq; u8 *pos; int frag_threshold = tx->local->fragmentation_threshold; if (!(tx->flags & IEEE80211_TX_FRAGMENTED)) return TX_CONTINUE; /* * Warn when submitting a fragmented A-MPDU frame and drop it. * This scenario is handled in __ieee80211_tx_prepare but extra * caution taken here as fragmented ampdu may cause Tx stop. */ if (WARN_ON(tx->flags & IEEE80211_TX_CTL_AMPDU || skb_get_queue_mapping(tx->skb) >= ieee80211_num_regular_queues(&tx->local->hw))) return TX_DROP; first = tx->skb; hdrlen = ieee80211_get_hdrlen(tx->fc); payload_len = first->len - hdrlen; per_fragm = frag_threshold - hdrlen - FCS_LEN; num_fragm = DIV_ROUND_UP(payload_len, per_fragm); frags = kzalloc(num_fragm * sizeof(struct sk_buff *), GFP_ATOMIC); if (!frags) goto fail; hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREFRAGS); seq = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ; pos = first->data + hdrlen + per_fragm; left = payload_len - per_fragm; for (i = 0; i < num_fragm - 1; i++) { struct ieee80211_hdr *fhdr; size_t copylen; if (left <= 0) goto fail; /* reserve enough extra head and tail room for possible * encryption */ frag = frags[i] = dev_alloc_skb(tx->local->tx_headroom + frag_threshold + IEEE80211_ENCRYPT_HEADROOM + IEEE80211_ENCRYPT_TAILROOM); if (!frag) goto fail; /* Make sure that all fragments use the same priority so * that they end up using the same TX queue */ frag->priority = first->priority; skb_reserve(frag, tx->local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM); fhdr = (struct ieee80211_hdr *) skb_put(frag, hdrlen); memcpy(fhdr, first->data, hdrlen); if (i == num_fragm - 2) fhdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREFRAGS); fhdr->seq_ctrl = cpu_to_le16(seq | ((i + 1) & IEEE80211_SCTL_FRAG)); copylen = left > per_fragm ? per_fragm : left; memcpy(skb_put(frag, copylen), pos, copylen); pos += copylen; left -= copylen; } skb_trim(first, hdrlen + per_fragm); tx->num_extra_frag = num_fragm - 1; tx->extra_frag = frags; return TX_CONTINUE; fail: printk(KERN_DEBUG "%s: failed to fragment frame\n", tx->dev->name); if (frags) { for (i = 0; i < num_fragm - 1; i++) if (frags[i]) dev_kfree_skb(frags[i]); kfree(frags); } I802_DEBUG_INC(tx->local->tx_handlers_drop_fragment); return TX_DROP; } static ieee80211_tx_result ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx) { if (!tx->key) return TX_CONTINUE; switch (tx->key->conf.alg) { case ALG_WEP: return ieee80211_crypto_wep_encrypt(tx); case ALG_TKIP: return ieee80211_crypto_tkip_encrypt(tx); case ALG_CCMP: return ieee80211_crypto_ccmp_encrypt(tx); } /* not reached */ WARN_ON(1); return TX_DROP; } static ieee80211_tx_result ieee80211_tx_h_stats(struct ieee80211_tx_data *tx) { int i; if (!tx->sta) return TX_CONTINUE; tx->sta->tx_packets++; tx->sta->tx_fragments++; tx->sta->tx_bytes += tx->skb->len; if (tx->extra_frag) { tx->sta->tx_fragments += tx->num_extra_frag; for (i = 0; i < tx->num_extra_frag; i++) tx->sta->tx_bytes += tx->extra_frag[i]->len; } return TX_CONTINUE; } typedef ieee80211_tx_result (*ieee80211_tx_handler)(struct ieee80211_tx_data *); static ieee80211_tx_handler ieee80211_tx_handlers[] = { ieee80211_tx_h_check_assoc, ieee80211_tx_h_sequence, ieee80211_tx_h_ps_buf, ieee80211_tx_h_select_key, ieee80211_tx_h_michael_mic_add, ieee80211_tx_h_rate_ctrl, ieee80211_tx_h_misc, ieee80211_tx_h_fragment, /* handlers after fragment must be aware of tx info fragmentation! */ ieee80211_tx_h_encrypt, ieee80211_tx_h_stats, NULL }; /* actual transmit path */ /* * deal with packet injection down monitor interface * with Radiotap Header -- only called for monitor mode interface */ static ieee80211_tx_result __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx, struct sk_buff *skb) { /* * this is the moment to interpret and discard the radiotap header that * must be at the start of the packet injected in Monitor mode * * Need to take some care with endian-ness since radiotap * args are little-endian */ struct ieee80211_radiotap_iterator iterator; struct ieee80211_radiotap_header *rthdr = (struct ieee80211_radiotap_header *) skb->data; struct ieee80211_supported_band *sband; int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len); struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); sband = tx->local->hw.wiphy->bands[tx->channel->band]; info->flags |= IEEE80211_TX_CTL_DO_NOT_ENCRYPT; info->flags |= IEEE80211_TX_CTL_INJECTED; tx->flags &= ~IEEE80211_TX_FRAGMENTED; /* * for every radiotap entry that is present * (ieee80211_radiotap_iterator_next returns -ENOENT when no more * entries present, or -EINVAL on error) */ while (!ret) { int i, target_rate; ret = ieee80211_radiotap_iterator_next(&iterator); if (ret) continue; /* see if this argument is something we can use */ switch (iterator.this_arg_index) { /* * You must take care when dereferencing iterator.this_arg * for multibyte types... the pointer is not aligned. Use * get_unaligned((type *)iterator.this_arg) to dereference * iterator.this_arg for type "type" safely on all arches. */ case IEEE80211_RADIOTAP_RATE: /* * radiotap rate u8 is in 500kbps units eg, 0x02=1Mbps * ieee80211 rate int is in 100kbps units eg, 0x0a=1Mbps */ target_rate = (*iterator.this_arg) * 5; for (i = 0; i < sband->n_bitrates; i++) { struct ieee80211_rate *r; r = &sband->bitrates[i]; if (r->bitrate == target_rate) { tx->rate_idx = i; break; } } break; case IEEE80211_RADIOTAP_ANTENNA: /* * radiotap uses 0 for 1st ant, mac80211 is 1 for * 1st ant */ info->antenna_sel_tx = (*iterator.this_arg) + 1; break; #if 0 case IEEE80211_RADIOTAP_DBM_TX_POWER: control->power_level = *iterator.this_arg; break; #endif case IEEE80211_RADIOTAP_FLAGS: if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) { /* * this indicates that the skb we have been * handed has the 32-bit FCS CRC at the end... * we should react to that by snipping it off * because it will be recomputed and added * on transmission */ if (skb->len < (iterator.max_length + FCS_LEN)) return TX_DROP; skb_trim(skb, skb->len - FCS_LEN); } if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP) info->flags &= ~IEEE80211_TX_CTL_DO_NOT_ENCRYPT; if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG) tx->flags |= IEEE80211_TX_FRAGMENTED; break; /* * Please update the file * Documentation/networking/mac80211-injection.txt * when parsing new fields here. */ default: break; } } if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */ return TX_DROP; /* * remove the radiotap header * iterator->max_length was sanity-checked against * skb->len by iterator init */ skb_pull(skb, iterator.max_length); return TX_CONTINUE; } /* * initialises @tx */ static ieee80211_tx_result __ieee80211_tx_prepare(struct ieee80211_tx_data *tx, struct sk_buff *skb, struct net_device *dev) { struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); struct ieee80211_hdr *hdr; struct ieee80211_sub_if_data *sdata; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); int hdrlen; memset(tx, 0, sizeof(*tx)); tx->skb = skb; tx->dev = dev; /* use original interface */ tx->local = local; tx->sdata = IEEE80211_DEV_TO_SUB_IF(dev); tx->channel = local->hw.conf.channel; tx->rate_idx = -1; tx->last_frag_rate_idx = -1; /* * Set this flag (used below to indicate "automatic fragmentation"), * it will be cleared/left by radiotap as desired. */ tx->flags |= IEEE80211_TX_FRAGMENTED; /* process and remove the injection radiotap header */ sdata = IEEE80211_DEV_TO_SUB_IF(dev); if (unlikely(sdata->vif.type == IEEE80211_IF_TYPE_MNTR)) { if (__ieee80211_parse_tx_radiotap(tx, skb) == TX_DROP) return TX_DROP; /* * __ieee80211_parse_tx_radiotap has now removed * the radiotap header that was present and pre-filled * 'tx' with tx control information. */ } hdr = (struct ieee80211_hdr *) skb->data; tx->sta = sta_info_get(local, hdr->addr1); tx->fc = le16_to_cpu(hdr->frame_control); if (is_multicast_ether_addr(hdr->addr1)) { tx->flags &= ~IEEE80211_TX_UNICAST; info->flags |= IEEE80211_TX_CTL_NO_ACK; } else { tx->flags |= IEEE80211_TX_UNICAST; info->flags &= ~IEEE80211_TX_CTL_NO_ACK; } if (tx->flags & IEEE80211_TX_FRAGMENTED) { if ((tx->flags & IEEE80211_TX_UNICAST) && skb->len + FCS_LEN > local->fragmentation_threshold && !local->ops->set_frag_threshold && !(info->flags & IEEE80211_TX_CTL_AMPDU)) tx->flags |= IEEE80211_TX_FRAGMENTED; else tx->flags &= ~IEEE80211_TX_FRAGMENTED; } if (!tx->sta) info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT)) info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; hdrlen = ieee80211_get_hdrlen(tx->fc); if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) { u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)]; tx->ethertype = (pos[0] << 8) | pos[1]; } info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT; return TX_CONTINUE; } /* * NB: @tx is uninitialised when passed in here */ static int ieee80211_tx_prepare(struct ieee80211_tx_data *tx, struct sk_buff *skb, struct net_device *mdev) { struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); struct net_device *dev; dev = dev_get_by_index(&init_net, info->control.ifindex); if (unlikely(dev && !is_ieee80211_device(dev, mdev))) { dev_put(dev); dev = NULL; } if (unlikely(!dev)) return -ENODEV; /* initialises tx with control */ __ieee80211_tx_prepare(tx, skb, dev); dev_put(dev); return 0; } static int __ieee80211_tx(struct ieee80211_local *local, struct sk_buff *skb, struct ieee80211_tx_data *tx) { struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); int ret, i; if (netif_subqueue_stopped(local->mdev, skb)) return IEEE80211_TX_AGAIN; if (skb) { ieee80211_dump_frame(wiphy_name(local->hw.wiphy), "TX to low-level driver", skb); ret = local->ops->tx(local_to_hw(local), skb); if (ret) return IEEE80211_TX_AGAIN; local->mdev->trans_start = jiffies; ieee80211_led_tx(local, 1); } if (tx->extra_frag) { for (i = 0; i < tx->num_extra_frag; i++) { if (!tx->extra_frag[i]) continue; info = IEEE80211_SKB_CB(tx->extra_frag[i]); info->flags &= ~(IEEE80211_TX_CTL_USE_RTS_CTS | IEEE80211_TX_CTL_USE_CTS_PROTECT | IEEE80211_TX_CTL_CLEAR_PS_FILT | IEEE80211_TX_CTL_FIRST_FRAGMENT); if (netif_subqueue_stopped(local->mdev, tx->extra_frag[i])) return IEEE80211_TX_FRAG_AGAIN; if (i == tx->num_extra_frag) { info->tx_rate_idx = tx->last_frag_rate_idx; if (tx->flags & IEEE80211_TX_PROBE_LAST_FRAG) info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE; else info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE; } ieee80211_dump_frame(wiphy_name(local->hw.wiphy), "TX to low-level driver", tx->extra_frag[i]); ret = local->ops->tx(local_to_hw(local), tx->extra_frag[i]); if (ret) return IEEE80211_TX_FRAG_AGAIN; local->mdev->trans_start = jiffies; ieee80211_led_tx(local, 1); tx->extra_frag[i] = NULL; } kfree(tx->extra_frag); tx->extra_frag = NULL; } return IEEE80211_TX_OK; } /* * Invoke TX handlers, return 0 on success and non-zero if the * frame was dropped or queued. */ static int invoke_tx_handlers(struct ieee80211_tx_data *tx) { struct ieee80211_local *local = tx->local; struct sk_buff *skb = tx->skb; ieee80211_tx_handler *handler; ieee80211_tx_result res = TX_DROP; int i; for (handler = ieee80211_tx_handlers; *handler != NULL; handler++) { res = (*handler)(tx); if (res != TX_CONTINUE) break; } if (unlikely(res == TX_DROP)) { I802_DEBUG_INC(local->tx_handlers_drop); dev_kfree_skb(skb); for (i = 0; i < tx->num_extra_frag; i++) if (tx->extra_frag[i]) dev_kfree_skb(tx->extra_frag[i]); kfree(tx->extra_frag); return -1; } else if (unlikely(res == TX_QUEUED)) { I802_DEBUG_INC(local->tx_handlers_queued); return -1; } return 0; } static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb) { struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); struct sta_info *sta; struct ieee80211_tx_data tx; ieee80211_tx_result res_prepare; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); int ret, i; u16 queue; queue = skb_get_queue_mapping(skb); WARN_ON(test_bit(queue, local->queues_pending)); if (unlikely(skb->len < 10)) { dev_kfree_skb(skb); return 0; } rcu_read_lock(); /* initialises tx */ res_prepare = __ieee80211_tx_prepare(&tx, skb, dev); if (res_prepare == TX_DROP) { dev_kfree_skb(skb); rcu_read_unlock(); return 0; } sta = tx.sta; tx.channel = local->hw.conf.channel; info->band = tx.channel->band; if (invoke_tx_handlers(&tx)) goto out; if (tx.extra_frag) { for (i = 0; i < tx.num_extra_frag; i++) { int next_len, dur; struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx.extra_frag[i]->data; if (i + 1 < tx.num_extra_frag) { next_len = tx.extra_frag[i + 1]->len; } else { next_len = 0; tx.rate_idx = tx.last_frag_rate_idx; } dur = ieee80211_duration(&tx, 0, next_len); hdr->duration_id = cpu_to_le16(dur); } } retry: ret = __ieee80211_tx(local, skb, &tx); if (ret) { struct ieee80211_tx_stored_packet *store; /* * Since there are no fragmented frames on A-MPDU * queues, there's no reason for a driver to reject * a frame there, warn and drop it. */ if (WARN_ON(queue >= ieee80211_num_regular_queues(&local->hw))) goto drop; store = &local->pending_packet[queue]; if (ret == IEEE80211_TX_FRAG_AGAIN) skb = NULL; set_bit(queue, local->queues_pending); smp_mb(); /* * When the driver gets out of buffers during sending of * fragments and calls ieee80211_stop_queue, the netif * subqueue is stopped. There is, however, a small window * in which the PENDING bit is not yet set. If a buffer * gets available in that window (i.e. driver calls * ieee80211_wake_queue), we would end up with ieee80211_tx * called with the PENDING bit still set. Prevent this by * continuing transmitting here when that situation is * possible to have happened. */ if (!__netif_subqueue_stopped(local->mdev, queue)) { clear_bit(queue, local->queues_pending); goto retry; } store->skb = skb; store->extra_frag = tx.extra_frag; store->num_extra_frag = tx.num_extra_frag; store->last_frag_rate_idx = tx.last_frag_rate_idx; store->last_frag_rate_ctrl_probe = !!(tx.flags & IEEE80211_TX_PROBE_LAST_FRAG); } out: rcu_read_unlock(); return 0; drop: if (skb) dev_kfree_skb(skb); for (i = 0; i < tx.num_extra_frag; i++) if (tx.extra_frag[i]) dev_kfree_skb(tx.extra_frag[i]); kfree(tx.extra_frag); rcu_read_unlock(); return 0; } /* device xmit handlers */ static int ieee80211_skb_resize(struct ieee80211_local *local, struct sk_buff *skb, int head_need, bool may_encrypt) { int tail_need = 0; /* * This could be optimised, devices that do full hardware * crypto (including TKIP MMIC) need no tailroom... But we * have no drivers for such devices currently. */ if (may_encrypt) { tail_need = IEEE80211_ENCRYPT_TAILROOM; tail_need -= skb_tailroom(skb); tail_need = max_t(int, tail_need, 0); } if (head_need || tail_need) { /* Sorry. Can't account for this any more */ skb_orphan(skb); } if (skb_header_cloned(skb)) I802_DEBUG_INC(local->tx_expand_skb_head_cloned); else I802_DEBUG_INC(local->tx_expand_skb_head); if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) { printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n", wiphy_name(local->hw.wiphy)); return -ENOMEM; } /* update truesize too */ skb->truesize += head_need + tail_need; return 0; } int ieee80211_master_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); struct net_device *odev = NULL; struct ieee80211_sub_if_data *osdata; int headroom; bool may_encrypt; int ret; if (info->control.ifindex) odev = dev_get_by_index(&init_net, info->control.ifindex); if (unlikely(odev && !is_ieee80211_device(odev, dev))) { dev_put(odev); odev = NULL; } if (unlikely(!odev)) { #ifdef CONFIG_MAC80211_VERBOSE_DEBUG printk(KERN_DEBUG "%s: Discarded packet with nonexistent " "originating device\n", dev->name); #endif dev_kfree_skb(skb); return 0; } osdata = IEEE80211_DEV_TO_SUB_IF(odev); may_encrypt = !(info->flags & IEEE80211_TX_CTL_DO_NOT_ENCRYPT); headroom = osdata->local->tx_headroom; if (may_encrypt) headroom += IEEE80211_ENCRYPT_HEADROOM; headroom -= skb_headroom(skb); headroom = max_t(int, 0, headroom); if (ieee80211_skb_resize(osdata->local, skb, headroom, may_encrypt)) { dev_kfree_skb(skb); dev_put(odev); return 0; } info->control.vif = &osdata->vif; ret = ieee80211_tx(odev, skb); dev_put(odev); return ret; } int ieee80211_monitor_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); struct ieee80211_radiotap_header *prthdr = (struct ieee80211_radiotap_header *)skb->data; u16 len_rthdr; /* check for not even having the fixed radiotap header part */ if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header))) goto fail; /* too short to be possibly valid */ /* is it a header version we can trust to find length from? */ if (unlikely(prthdr->it_version)) goto fail; /* only version 0 is supported */ /* then there must be a radiotap header with a length we can use */ len_rthdr = ieee80211_get_radiotap_len(skb->data); /* does the skb contain enough to deliver on the alleged length? */ if (unlikely(skb->len < len_rthdr)) goto fail; /* skb too short for claimed rt header extent */ skb->dev = local->mdev; /* needed because we set skb device to master */ info->control.ifindex = dev->ifindex; info->flags |= IEEE80211_TX_CTL_DO_NOT_ENCRYPT; /* Interfaces should always request a status report */ info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS; /* * fix up the pointers accounting for the radiotap * header still being in there. We are being given * a precooked IEEE80211 header so no need for * normal processing */ skb_set_mac_header(skb, len_rthdr); /* * these are just fixed to the end of the rt area since we * don't have any better information and at this point, nobody cares */ skb_set_network_header(skb, len_rthdr); skb_set_transport_header(skb, len_rthdr); /* pass the radiotap header up to the next stage intact */ dev_queue_xmit(skb); return NETDEV_TX_OK; fail: dev_kfree_skb(skb); return NETDEV_TX_OK; /* meaning, we dealt with the skb */ } /** * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type * subinterfaces (wlan#, WDS, and VLAN interfaces) * @skb: packet to be sent * @dev: incoming interface * * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will * not be freed, and caller is responsible for either retrying later or freeing * skb). * * This function takes in an Ethernet header and encapsulates it with suitable * IEEE 802.11 header based on which interface the packet is coming in. The * encapsulated packet will then be passed to master interface, wlan#.11, for * transmission (through low-level driver). */ int ieee80211_subif_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); struct ieee80211_tx_info *info; struct ieee80211_sub_if_data *sdata; int ret = 1, head_need; u16 ethertype, hdrlen, meshhdrlen = 0, fc; struct ieee80211_hdr hdr; struct ieee80211s_hdr mesh_hdr; const u8 *encaps_data; int encaps_len, skip_header_bytes; int nh_pos, h_pos; struct sta_info *sta; u32 sta_flags = 0; sdata = IEEE80211_DEV_TO_SUB_IF(dev); if (unlikely(skb->len < ETH_HLEN)) { printk(KERN_DEBUG "%s: short skb (len=%d)\n", dev->name, skb->len); ret = 0; goto fail; } nh_pos = skb_network_header(skb) - skb->data; h_pos = skb_transport_header(skb) - skb->data; /* convert Ethernet header to proper 802.11 header (based on * operation mode) */ ethertype = (skb->data[12] << 8) | skb->data[13]; fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA; switch (sdata->vif.type) { case IEEE80211_IF_TYPE_AP: case IEEE80211_IF_TYPE_VLAN: fc |= IEEE80211_FCTL_FROMDS; /* DA BSSID SA */ memcpy(hdr.addr1, skb->data, ETH_ALEN); memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN); hdrlen = 24; break; case IEEE80211_IF_TYPE_WDS: fc |= IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS; /* RA TA DA SA */ memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN); memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); memcpy(hdr.addr3, skb->data, ETH_ALEN); memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); hdrlen = 30; break; #ifdef CONFIG_MAC80211_MESH case IEEE80211_IF_TYPE_MESH_POINT: fc |= IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS; /* RA TA DA SA */ if (is_multicast_ether_addr(skb->data)) memcpy(hdr.addr1, skb->data, ETH_ALEN); else if (mesh_nexthop_lookup(hdr.addr1, skb, dev)) return 0; memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); memcpy(hdr.addr3, skb->data, ETH_ALEN); memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); if (skb->pkt_type == PACKET_OTHERHOST) { /* Forwarded frame, keep mesh ttl and seqnum */ struct ieee80211s_hdr *prev_meshhdr; prev_meshhdr = ((struct ieee80211s_hdr *)skb->cb); meshhdrlen = ieee80211_get_mesh_hdrlen(prev_meshhdr); memcpy(&mesh_hdr, prev_meshhdr, meshhdrlen); sdata->u.sta.mshstats.fwded_frames++; } else { if (!sdata->u.sta.mshcfg.dot11MeshTTL) { /* Do not send frames with mesh_ttl == 0 */ sdata->u.sta.mshstats.dropped_frames_ttl++; ret = 0; goto fail; } meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, sdata); } hdrlen = 30; break; #endif case IEEE80211_IF_TYPE_STA: fc |= IEEE80211_FCTL_TODS; /* BSSID SA DA */ memcpy(hdr.addr1, sdata->u.sta.bssid, ETH_ALEN); memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); memcpy(hdr.addr3, skb->data, ETH_ALEN); hdrlen = 24; break; case IEEE80211_IF_TYPE_IBSS: /* DA SA BSSID */ memcpy(hdr.addr1, skb->data, ETH_ALEN); memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); memcpy(hdr.addr3, sdata->u.sta.bssid, ETH_ALEN); hdrlen = 24; break; default: ret = 0; goto fail; } /* * There's no need to try to look up the destination * if it is a multicast address (which can only happen * in AP mode) */ if (!is_multicast_ether_addr(hdr.addr1)) { rcu_read_lock(); sta = sta_info_get(local, hdr.addr1); if (sta) sta_flags = get_sta_flags(sta); rcu_read_unlock(); } /* receiver and we are QoS enabled, use a QoS type frame */ if (sta_flags & WLAN_STA_WME && ieee80211_num_regular_queues(&local->hw) >= 4) { fc |= IEEE80211_STYPE_QOS_DATA; hdrlen += 2; } /* * Drop unicast frames to unauthorised stations unless they are * EAPOL frames from the local station. */ if (unlikely(!is_multicast_ether_addr(hdr.addr1) && !(sta_flags & WLAN_STA_AUTHORIZED) && !(ethertype == ETH_P_PAE && compare_ether_addr(dev->dev_addr, skb->data + ETH_ALEN) == 0))) { #ifdef CONFIG_MAC80211_VERBOSE_DEBUG DECLARE_MAC_BUF(mac); if (net_ratelimit()) printk(KERN_DEBUG "%s: dropped frame to %s" " (unauthorized port)\n", dev->name, print_mac(mac, hdr.addr1)); #endif I802_DEBUG_INC(local->tx_handlers_drop_unauth_port); ret = 0; goto fail; } hdr.frame_control = cpu_to_le16(fc); hdr.duration_id = 0; hdr.seq_ctrl = 0; skip_header_bytes = ETH_HLEN; if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) { encaps_data = bridge_tunnel_header; encaps_len = sizeof(bridge_tunnel_header); skip_header_bytes -= 2; } else if (ethertype >= 0x600) { encaps_data = rfc1042_header; encaps_len = sizeof(rfc1042_header); skip_header_bytes -= 2; } else { encaps_data = NULL; encaps_len = 0; } skb_pull(skb, skip_header_bytes); nh_pos -= skip_header_bytes; h_pos -= skip_header_bytes; /* TODO: implement support for fragments so that there is no need to * reallocate and copy payload; it might be enough to support one * extra fragment that would be copied in the beginning of the frame * data.. anyway, it would be nice to include this into skb structure * somehow * * There are few options for this: * use skb->cb as an extra space for 802.11 header * allocate new buffer if not enough headroom * make sure that there is enough headroom in every skb by increasing * build in headroom in __dev_alloc_skb() (linux/skbuff.h) and * alloc_skb() (net/core/skbuff.c) */ head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb); /* * So we need to modify the skb header and hence need a copy of * that. The head_need variable above doesn't, so far, include * the needed header space that we don't need right away. If we * can, then we don't reallocate right now but only after the * frame arrives at the master device (if it does...) * * If we cannot, however, then we will reallocate to include all * the ever needed space. Also, if we need to reallocate it anyway, * make it big enough for everything we may ever need. */ if (head_need > 0 || skb_cloned(skb)) { head_need += IEEE80211_ENCRYPT_HEADROOM; head_need += local->tx_headroom; head_need = max_t(int, 0, head_need); if (ieee80211_skb_resize(local, skb, head_need, true)) goto fail; } if (encaps_data) { memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len); nh_pos += encaps_len; h_pos += encaps_len; } if (meshhdrlen > 0) { memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen); nh_pos += meshhdrlen; h_pos += meshhdrlen; } if (fc & IEEE80211_STYPE_QOS_DATA) { __le16 *qos_control; qos_control = (__le16*) skb_push(skb, 2); memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2); /* * Maybe we could actually set some fields here, for now just * initialise to zero to indicate no special operation. */ *qos_control = 0; } else memcpy(skb_push(skb, hdrlen), &hdr, hdrlen); nh_pos += hdrlen; h_pos += hdrlen; info = IEEE80211_SKB_CB(skb); memset(info, 0, sizeof(*info)); info->control.ifindex = dev->ifindex; if (ethertype == ETH_P_PAE) info->flags |= IEEE80211_TX_CTL_EAPOL_FRAME; /* Interfaces should always request a status report */ info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS; skb->dev = local->mdev; dev->stats.tx_packets++; dev->stats.tx_bytes += skb->len; /* Update skb pointers to various headers since this modified frame * is going to go through Linux networking code that may potentially * need things like pointer to IP header. */ skb_set_mac_header(skb, 0); skb_set_network_header(skb, nh_pos); skb_set_transport_header(skb, h_pos); dev->trans_start = jiffies; dev_queue_xmit(skb); return 0; fail: if (!ret) dev_kfree_skb(skb); return ret; } /* * ieee80211_clear_tx_pending may not be called in a context where * it is possible that it packets could come in again. */ void ieee80211_clear_tx_pending(struct ieee80211_local *local) { int i, j; struct ieee80211_tx_stored_packet *store; for (i = 0; i < ieee80211_num_regular_queues(&local->hw); i++) { if (!test_bit(i, local->queues_pending)) continue; store = &local->pending_packet[i]; kfree_skb(store->skb); for (j = 0; j < store->num_extra_frag; j++) kfree_skb(store->extra_frag[j]); kfree(store->extra_frag); clear_bit(i, local->queues_pending); } } /* * Transmit all pending packets. Called from tasklet, locks master device * TX lock so that no new packets can come in. */ void ieee80211_tx_pending(unsigned long data) { struct ieee80211_local *local = (struct ieee80211_local *)data; struct net_device *dev = local->mdev; struct ieee80211_tx_stored_packet *store; struct ieee80211_tx_data tx; int i, ret; netif_tx_lock_bh(dev); for (i = 0; i < ieee80211_num_regular_queues(&local->hw); i++) { /* Check that this queue is ok */ if (__netif_subqueue_stopped(local->mdev, i)) continue; if (!test_bit(i, local->queues_pending)) { ieee80211_wake_queue(&local->hw, i); continue; } store = &local->pending_packet[i]; tx.extra_frag = store->extra_frag; tx.num_extra_frag = store->num_extra_frag; tx.last_frag_rate_idx = store->last_frag_rate_idx; tx.flags = 0; if (store->last_frag_rate_ctrl_probe) tx.flags |= IEEE80211_TX_PROBE_LAST_FRAG; ret = __ieee80211_tx(local, store->skb, &tx); if (ret) { if (ret == IEEE80211_TX_FRAG_AGAIN) store->skb = NULL; } else { clear_bit(i, local->queues_pending); ieee80211_wake_queue(&local->hw, i); } } netif_tx_unlock_bh(dev); } /* functions for drivers to get certain frames */ static void ieee80211_beacon_add_tim(struct ieee80211_local *local, struct ieee80211_if_ap *bss, struct sk_buff *skb, struct beacon_data *beacon) { u8 *pos, *tim; int aid0 = 0; int i, have_bits = 0, n1, n2; /* Generate bitmap for TIM only if there are any STAs in power save * mode. */ if (atomic_read(&bss->num_sta_ps) > 0) /* in the hope that this is faster than * checking byte-for-byte */ have_bits = !bitmap_empty((unsigned long*)bss->tim, IEEE80211_MAX_AID+1); if (bss->dtim_count == 0) bss->dtim_count = beacon->dtim_period - 1; else bss->dtim_count--; tim = pos = (u8 *) skb_put(skb, 6); *pos++ = WLAN_EID_TIM; *pos++ = 4; *pos++ = bss->dtim_count; *pos++ = beacon->dtim_period; if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf)) aid0 = 1; if (have_bits) { /* Find largest even number N1 so that bits numbered 1 through * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits * (N2 + 1) x 8 through 2007 are 0. */ n1 = 0; for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) { if (bss->tim[i]) { n1 = i & 0xfe; break; } } n2 = n1; for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) { if (bss->tim[i]) { n2 = i; break; } } /* Bitmap control */ *pos++ = n1 | aid0; /* Part Virt Bitmap */ memcpy(pos, bss->tim + n1, n2 - n1 + 1); tim[1] = n2 - n1 + 4; skb_put(skb, n2 - n1); } else { *pos++ = aid0; /* Bitmap control */ *pos++ = 0; /* Part Virt Bitmap */ } } struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif) { struct ieee80211_local *local = hw_to_local(hw); struct sk_buff *skb; struct ieee80211_tx_info *info; struct net_device *bdev; struct ieee80211_sub_if_data *sdata = NULL; struct ieee80211_if_ap *ap = NULL; struct rate_selection rsel; struct beacon_data *beacon; struct ieee80211_supported_band *sband; struct ieee80211_mgmt *mgmt; int *num_beacons; bool err = true; enum ieee80211_band band = local->hw.conf.channel->band; u8 *pos; sband = local->hw.wiphy->bands[band]; rcu_read_lock(); sdata = vif_to_sdata(vif); bdev = sdata->dev; if (sdata->vif.type == IEEE80211_IF_TYPE_AP) { ap = &sdata->u.ap; beacon = rcu_dereference(ap->beacon); if (ap && beacon) { /* * headroom, head length, * tail length and maximum TIM length */ skb = dev_alloc_skb(local->tx_headroom + beacon->head_len + beacon->tail_len + 256); if (!skb) goto out; skb_reserve(skb, local->tx_headroom); memcpy(skb_put(skb, beacon->head_len), beacon->head, beacon->head_len); ieee80211_include_sequence(sdata, (struct ieee80211_hdr *)skb->data); /* * Not very nice, but we want to allow the driver to call * ieee80211_beacon_get() as a response to the set_tim() * callback. That, however, is already invoked under the * sta_lock to guarantee consistent and race-free update * of the tim bitmap in mac80211 and the driver. */ if (local->tim_in_locked_section) { ieee80211_beacon_add_tim(local, ap, skb, beacon); } else { unsigned long flags; spin_lock_irqsave(&local->sta_lock, flags); ieee80211_beacon_add_tim(local, ap, skb, beacon); spin_unlock_irqrestore(&local->sta_lock, flags); } if (beacon->tail) memcpy(skb_put(skb, beacon->tail_len), beacon->tail, beacon->tail_len); num_beacons = &ap->num_beacons; err = false; } } else if (ieee80211_vif_is_mesh(&sdata->vif)) { /* headroom, head length, tail length and maximum TIM length */ skb = dev_alloc_skb(local->tx_headroom + 400); if (!skb) goto out; skb_reserve(skb, local->hw.extra_tx_headroom); mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24 + sizeof(mgmt->u.beacon)); memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT, IEEE80211_STYPE_BEACON); memset(mgmt->da, 0xff, ETH_ALEN); memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN); /* BSSID is left zeroed, wildcard value */ mgmt->u.beacon.beacon_int = cpu_to_le16(local->hw.conf.beacon_int); mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */ pos = skb_put(skb, 2); *pos++ = WLAN_EID_SSID; *pos++ = 0x0; mesh_mgmt_ies_add(skb, sdata->dev); num_beacons = &sdata->u.sta.num_beacons; err = false; } if (err) { #ifdef CONFIG_MAC80211_VERBOSE_DEBUG if (net_ratelimit()) printk(KERN_DEBUG "no beacon data avail for %s\n", bdev->name); #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ skb = NULL; goto out; } info = IEEE80211_SKB_CB(skb); info->band = band; rate_control_get_rate(local->mdev, sband, skb, &rsel); if (unlikely(rsel.rate_idx < 0)) { if (net_ratelimit()) { printk(KERN_DEBUG "%s: ieee80211_beacon_get: " "no rate found\n", wiphy_name(local->hw.wiphy)); } dev_kfree_skb(skb); skb = NULL; goto out; } info->control.vif = vif; info->tx_rate_idx = rsel.rate_idx; if (sdata->bss_conf.use_short_preamble && sband->bitrates[rsel.rate_idx].flags & IEEE80211_RATE_SHORT_PREAMBLE) info->flags |= IEEE80211_TX_CTL_SHORT_PREAMBLE; info->antenna_sel_tx = local->hw.conf.antenna_sel_tx; info->flags |= IEEE80211_TX_CTL_NO_ACK; info->flags |= IEEE80211_TX_CTL_DO_NOT_ENCRYPT; info->control.retry_limit = 1; info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; (*num_beacons)++; out: rcu_read_unlock(); return skb; } EXPORT_SYMBOL(ieee80211_beacon_get); void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, const void *frame, size_t frame_len, const struct ieee80211_tx_info *frame_txctl, struct ieee80211_rts *rts) { const struct ieee80211_hdr *hdr = frame; u16 fctl; fctl = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS; rts->frame_control = cpu_to_le16(fctl); rts->duration = ieee80211_rts_duration(hw, vif, frame_len, frame_txctl); memcpy(rts->ra, hdr->addr1, sizeof(rts->ra)); memcpy(rts->ta, hdr->addr2, sizeof(rts->ta)); } EXPORT_SYMBOL(ieee80211_rts_get); void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, const void *frame, size_t frame_len, const struct ieee80211_tx_info *frame_txctl, struct ieee80211_cts *cts) { const struct ieee80211_hdr *hdr = frame; u16 fctl; fctl = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS; cts->frame_control = cpu_to_le16(fctl); cts->duration = ieee80211_ctstoself_duration(hw, vif, frame_len, frame_txctl); memcpy(cts->ra, hdr->addr1, sizeof(cts->ra)); } EXPORT_SYMBOL(ieee80211_ctstoself_get); struct sk_buff * ieee80211_get_buffered_bc(struct ieee80211_hw *hw, struct ieee80211_vif *vif) { struct ieee80211_local *local = hw_to_local(hw); struct sk_buff *skb = NULL; struct sta_info *sta; struct ieee80211_tx_data tx; struct net_device *bdev; struct ieee80211_sub_if_data *sdata; struct ieee80211_if_ap *bss = NULL; struct beacon_data *beacon; struct ieee80211_tx_info *info; sdata = vif_to_sdata(vif); bdev = sdata->dev; bss = &sdata->u.ap; if (!bss) return NULL; rcu_read_lock(); beacon = rcu_dereference(bss->beacon); if (sdata->vif.type != IEEE80211_IF_TYPE_AP || !beacon || !beacon->head) goto out; if (bss->dtim_count != 0) goto out; /* send buffered bc/mc only after DTIM beacon */ while (1) { skb = skb_dequeue(&bss->ps_bc_buf); if (!skb) goto out; local->total_ps_buffered--; if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; /* more buffered multicast/broadcast frames ==> set * MoreData flag in IEEE 802.11 header to inform PS * STAs */ hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA); } if (!ieee80211_tx_prepare(&tx, skb, local->mdev)) break; dev_kfree_skb_any(skb); } info = IEEE80211_SKB_CB(skb); sta = tx.sta; tx.flags |= IEEE80211_TX_PS_BUFFERED; tx.channel = local->hw.conf.channel; info->band = tx.channel->band; if (invoke_tx_handlers(&tx)) skb = NULL; out: rcu_read_unlock(); return skb; } EXPORT_SYMBOL(ieee80211_get_buffered_bc);