diff options
Diffstat (limited to 'net/mac80211/tx.c')
| -rw-r--r-- | net/mac80211/tx.c | 1869 |
1 files changed, 1869 insertions, 0 deletions
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c new file mode 100644 index 00000000000..dc128b412ea --- /dev/null +++ b/net/mac80211/tx.c @@ -0,0 +1,1869 @@ +/* + * Copyright 2002-2005, Instant802 Networks, Inc. + * Copyright 2005-2006, Devicescape Software, Inc. + * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> + * Copyright 2007 Johannes Berg <johannes@sipsolutions.net> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * + * Transmit and frame generation functions. + */ + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/skbuff.h> +#include <linux/etherdevice.h> +#include <linux/bitmap.h> +#include <net/ieee80211_radiotap.h> +#include <net/cfg80211.h> +#include <net/mac80211.h> +#include <asm/unaligned.h> + +#include "ieee80211_i.h" +#include "ieee80211_led.h" +#include "wep.h" +#include "wpa.h" +#include "wme.h" +#include "ieee80211_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; + + 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=" MAC_FMT, MAC_ARG(hdr->addr1)); + if (hdrlen >= 16) + printk(" A2=" MAC_FMT, MAC_ARG(hdr->addr2)); + if (hdrlen >= 24) + printk(" A3=" MAC_FMT, MAC_ARG(hdr->addr3)); + if (hdrlen >= 30) + printk(" A4=" MAC_FMT, MAC_ARG(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_txrx_data *tx, int group_addr, + int next_frag_len) +{ + int rate, mrate, erp, dur, i; + struct ieee80211_rate *txrate = tx->u.tx.rate; + struct ieee80211_local *local = tx->local; + struct ieee80211_hw_mode *mode = tx->u.tx.mode; + + erp = txrate->flags & IEEE80211_RATE_ERP; + + /* + * 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; + mrate = 10; /* use 1 Mbps if everything fails */ + for (i = 0; i < mode->num_rates; i++) { + struct ieee80211_rate *r = &mode->rates[i]; + if (r->rate > txrate->rate) + break; + + if (IEEE80211_RATE_MODULATION(txrate->flags) != + IEEE80211_RATE_MODULATION(r->flags)) + continue; + + if (r->flags & IEEE80211_RATE_BASIC) + rate = r->rate; + else if (r->flags & IEEE80211_RATE_MANDATORY) + mrate = r->rate; + } + 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, + local->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->rate, erp, + local->short_preamble); + } + + return dur; +} + +static inline int __ieee80211_queue_stopped(const struct ieee80211_local *local, + int queue) +{ + return test_bit(IEEE80211_LINK_STATE_XOFF, &local->state[queue]); +} + +static inline int __ieee80211_queue_pending(const struct ieee80211_local *local, + int queue) +{ + return test_bit(IEEE80211_LINK_STATE_PENDING, &local->state[queue]); +} + +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_txrx_result +ieee80211_tx_h_check_assoc(struct ieee80211_txrx_data *tx) +{ +#ifdef CONFIG_MAC80211_VERBOSE_DEBUG + struct sk_buff *skb = tx->skb; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; +#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ + u32 sta_flags; + + if (unlikely(tx->local->sta_scanning != 0) && + ((tx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT || + (tx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PROBE_REQ)) + return TXRX_DROP; + + if (tx->u.tx.ps_buffered) + return TXRX_CONTINUE; + + sta_flags = tx->sta ? tx->sta->flags : 0; + + if (likely(tx->u.tx.unicast)) { + if (unlikely(!(sta_flags & WLAN_STA_ASSOC) && + tx->sdata->type != IEEE80211_IF_TYPE_IBSS && + (tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)) { +#ifdef CONFIG_MAC80211_VERBOSE_DEBUG + printk(KERN_DEBUG "%s: dropped data frame to not " + "associated station " MAC_FMT "\n", + tx->dev->name, MAC_ARG(hdr->addr1)); +#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ + I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc); + return TXRX_DROP; + } + } else { + if (unlikely((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA && + tx->local->num_sta == 0 && + !tx->local->allow_broadcast_always && + tx->sdata->type != IEEE80211_IF_TYPE_IBSS)) { + /* + * No associated STAs - no need to send multicast + * frames. + */ + return TXRX_DROP; + } + return TXRX_CONTINUE; + } + + if (unlikely(!tx->u.tx.mgmt_interface && tx->sdata->ieee802_1x && + !(sta_flags & WLAN_STA_AUTHORIZED))) { +#ifdef CONFIG_MAC80211_VERBOSE_DEBUG + printk(KERN_DEBUG "%s: dropped frame to " MAC_FMT + " (unauthorized port)\n", tx->dev->name, + MAC_ARG(hdr->addr1)); +#endif + I802_DEBUG_INC(tx->local->tx_handlers_drop_unauth_port); + return TXRX_DROP; + } + + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_tx_h_sequence(struct ieee80211_txrx_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 TXRX_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; + + read_lock(&local->sub_if_lock); + list_for_each_entry(sdata, &local->sub_if_list, list) { + struct ieee80211_if_ap *ap; + if (sdata->dev == local->mdev || + sdata->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); + } + read_unlock(&local->sub_if_lock); + + spin_lock_bh(&local->sta_lock); + list_for_each_entry(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); + } + spin_unlock_bh(&local->sta_lock); + + local->total_ps_buffered = total; + printk(KERN_DEBUG "%s: PS buffers full - purged %d frames\n", + local->mdev->name, purged); +} + +static inline ieee80211_txrx_result +ieee80211_tx_h_multicast_ps_buf(struct ieee80211_txrx_data *tx) +{ + /* 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 */ + if ((tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING) && + tx->sdata->type != IEEE80211_IF_TYPE_WDS && + tx->sdata->bss && atomic_read(&tx->sdata->bss->num_sta_ps) && + !(tx->fc & IEEE80211_FCTL_ORDER)) { + 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 TXRX_QUEUED; + } + + return TXRX_CONTINUE; +} + +static inline ieee80211_txrx_result +ieee80211_tx_h_unicast_ps_buf(struct ieee80211_txrx_data *tx) +{ + struct sta_info *sta = tx->sta; + + if (unlikely(!sta || + ((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT && + (tx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PROBE_RESP))) + return TXRX_CONTINUE; + + if (unlikely((sta->flags & WLAN_STA_PS) && !sta->pspoll)) { + struct ieee80211_tx_packet_data *pkt_data; +#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG + printk(KERN_DEBUG "STA " MAC_FMT " aid %d: PS buffer (entries " + "before %d)\n", + MAC_ARG(sta->addr), sta->aid, + skb_queue_len(&sta->ps_tx_buf)); +#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ + sta->flags |= WLAN_STA_TIM; + 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 " MAC_FMT " TX " + "buffer full - dropping oldest frame\n", + tx->dev->name, MAC_ARG(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)) { + if (tx->local->ops->set_tim) + tx->local->ops->set_tim(local_to_hw(tx->local), + sta->aid, 1); + if (tx->sdata->bss) + bss_tim_set(tx->local, tx->sdata->bss, sta->aid); + } + pkt_data = (struct ieee80211_tx_packet_data *)tx->skb->cb; + pkt_data->jiffies = jiffies; + skb_queue_tail(&sta->ps_tx_buf, tx->skb); + return TXRX_QUEUED; + } +#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG + else if (unlikely(sta->flags & WLAN_STA_PS)) { + printk(KERN_DEBUG "%s: STA " MAC_FMT " in PS mode, but pspoll " + "set -> send frame\n", tx->dev->name, + MAC_ARG(sta->addr)); + } +#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ + sta->pspoll = 0; + + return TXRX_CONTINUE; +} + + +static ieee80211_txrx_result +ieee80211_tx_h_ps_buf(struct ieee80211_txrx_data *tx) +{ + if (unlikely(tx->u.tx.ps_buffered)) + return TXRX_CONTINUE; + + if (tx->u.tx.unicast) + return ieee80211_tx_h_unicast_ps_buf(tx); + else + return ieee80211_tx_h_multicast_ps_buf(tx); +} + + + + +static ieee80211_txrx_result +ieee80211_tx_h_select_key(struct ieee80211_txrx_data *tx) +{ + if (tx->sta) + tx->u.tx.control->key_idx = tx->sta->key_idx_compression; + else + tx->u.tx.control->key_idx = HW_KEY_IDX_INVALID; + + if (unlikely(tx->u.tx.control->flags & IEEE80211_TXCTL_DO_NOT_ENCRYPT)) + tx->key = NULL; + else if (tx->sta && tx->sta->key) + tx->key = tx->sta->key; + else if (tx->sdata->default_key) + tx->key = tx->sdata->default_key; + else if (tx->sdata->drop_unencrypted && + !(tx->sdata->eapol && ieee80211_is_eapol(tx->skb))) { + I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted); + return TXRX_DROP; + } else + tx->key = NULL; + + if (tx->key) { + tx->key->tx_rx_count++; + if (unlikely(tx->local->key_tx_rx_threshold && + tx->key->tx_rx_count > + tx->local->key_tx_rx_threshold)) { + ieee80211_key_threshold_notify(tx->dev, tx->key, + tx->sta); + } + } + + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_tx_h_fragment(struct ieee80211_txrx_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->fragmented) + return TXRX_CONTINUE; + + first = tx->skb; + + hdrlen = ieee80211_get_hdrlen(tx->fc); + payload_len = first->len - hdrlen; + per_fragm = frag_threshold - hdrlen - FCS_LEN; + num_fragm = (payload_len + per_fragm - 1) / 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->u.tx.num_extra_frag = num_fragm - 1; + tx->u.tx.extra_frag = frags; + + return TXRX_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 TXRX_DROP; +} + +static int wep_encrypt_skb(struct ieee80211_txrx_data *tx, struct sk_buff *skb) +{ + if (tx->key->force_sw_encrypt) { + if (ieee80211_wep_encrypt(tx->local, skb, tx->key)) + return -1; + } else { + tx->u.tx.control->key_idx = tx->key->hw_key_idx; + if (tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) { + if (ieee80211_wep_add_iv(tx->local, skb, tx->key) == + NULL) + return -1; + } + } + return 0; +} + +static ieee80211_txrx_result +ieee80211_tx_h_wep_encrypt(struct ieee80211_txrx_data *tx) +{ + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data; + u16 fc; + + fc = le16_to_cpu(hdr->frame_control); + + if (!tx->key || tx->key->alg != ALG_WEP || + ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA && + ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT || + (fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH))) + return TXRX_CONTINUE; + + tx->u.tx.control->iv_len = WEP_IV_LEN; + tx->u.tx.control->icv_len = WEP_ICV_LEN; + ieee80211_tx_set_iswep(tx); + + if (wep_encrypt_skb(tx, tx->skb) < 0) { + I802_DEBUG_INC(tx->local->tx_handlers_drop_wep); + return TXRX_DROP; + } + + if (tx->u.tx.extra_frag) { + int i; + for (i = 0; i < tx->u.tx.num_extra_frag; i++) { + if (wep_encrypt_skb(tx, tx->u.tx.extra_frag[i]) < 0) { + I802_DEBUG_INC(tx->local-> + tx_handlers_drop_wep); + return TXRX_DROP; + } + } + } + + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_tx_h_rate_ctrl(struct ieee80211_txrx_data *tx) +{ + struct rate_control_extra extra; + + memset(&extra, 0, sizeof(extra)); + extra.mode = tx->u.tx.mode; + extra.mgmt_data = tx->sdata && + tx->sdata->type == IEEE80211_IF_TYPE_MGMT; + extra.ethertype = tx->ethertype; + + tx->u.tx.rate = rate_control_get_rate(tx->local, tx->dev, tx->skb, + &extra); + if (unlikely(extra.probe != NULL)) { + tx->u.tx.control->flags |= IEEE80211_TXCTL_RATE_CTRL_PROBE; + tx->u.tx.probe_last_frag = 1; + tx->u.tx.control->alt_retry_rate = tx->u.tx.rate->val; + tx->u.tx.rate = extra.probe; + } else { + tx->u.tx.control->alt_retry_rate = -1; + } + if (!tx->u.tx.rate) + return TXRX_DROP; + if (tx->u.tx.mode->mode == MODE_IEEE80211G && + tx->sdata->use_protection && tx->fragmented && + extra.nonerp) { + tx->u.tx.last_frag_rate = tx->u.tx.rate; + tx->u.tx.probe_last_frag = extra.probe ? 1 : 0; + + tx->u.tx.rate = extra.nonerp; + tx->u.tx.control->rate = extra.nonerp; + tx->u.tx.control->flags &= ~IEEE80211_TXCTL_RATE_CTRL_PROBE; + } else { + tx->u.tx.last_frag_rate = tx->u.tx.rate; + tx->u.tx.control->rate = tx->u.tx.rate; + } + tx->u.tx.control->tx_rate = tx->u.tx.rate->val; + if ((tx->u.tx.rate->flags & IEEE80211_RATE_PREAMBLE2) && + tx->local->short_preamble && + (!tx->sta || (tx->sta->flags & WLAN_STA_SHORT_PREAMBLE))) { + tx->u.tx.short_preamble = 1; + tx->u.tx.control->tx_rate = tx->u.tx.rate->val2; + } + + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_tx_h_misc(struct ieee80211_txrx_data *tx) +{ + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data; + u16 dur; + struct ieee80211_tx_control *control = tx->u.tx.control; + struct ieee80211_hw_mode *mode = tx->u.tx.mode; + + if (!is_multicast_ether_addr(hdr->addr1)) { + if (tx->skb->len + FCS_LEN > tx->local->rts_threshold && + tx->local->rts_threshold < IEEE80211_MAX_RTS_THRESHOLD) { + control->flags |= IEEE80211_TXCTL_USE_RTS_CTS; + control->retry_limit = + tx->local->long_retry_limit; + } else { + control->retry_limit = + tx->local->short_retry_limit; + } + } else { + control->retry_limit = 1; + } + + if (tx->fragmented) { + /* Do not use multiple retry rates when sending fragmented + * frames. + * TODO: The last fragment could still use multiple retry + * rates. */ + control->alt_retry_rate = -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 (mode->mode == MODE_IEEE80211G && + (tx->u.tx.rate->flags & IEEE80211_RATE_ERP) && + tx->u.tx.unicast && tx->sdata->use_protection && + !(control->flags & IEEE80211_TXCTL_USE_RTS_CTS)) + control->flags |= IEEE80211_TXCTL_USE_CTS_PROTECT; + + /* 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->fragmented ? tx->u.tx.extra_frag[0]->len : + 0); + hdr->duration_id = cpu_to_le16(dur); + + if ((control->flags & IEEE80211_TXCTL_USE_RTS_CTS) || + (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)) { + struct ieee80211_rate *rate; + + /* Do not use multiple retry rates when using RTS/CTS */ + control->alt_retry_rate = -1; + + /* Use min(data rate, max base rate) as CTS/RTS rate */ + rate = tx->u.tx.rate; + while (rate > mode->rates && + !(rate->flags & IEEE80211_RATE_BASIC)) + rate--; + + control->rts_cts_rate = rate->val; + control->rts_rate = rate; + } + + if (tx->sta) { + tx->sta->tx_packets++; + tx->sta->tx_fragments++; + tx->sta->tx_bytes += tx->skb->len; + if (tx->u.tx.extra_frag) { + int i; + tx->sta->tx_fragments += tx->u.tx.num_extra_frag; + for (i = 0; i < tx->u.tx.num_extra_frag; i++) { + tx->sta->tx_bytes += + tx->u.tx.extra_frag[i]->len; + } + } + } + + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result +ieee80211_tx_h_load_stats(struct ieee80211_txrx_data *tx) +{ + struct ieee80211_local *local = tx->local; + struct ieee80211_hw_mode *mode = tx->u.tx.mode; + struct sk_buff *skb = tx->skb; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + u32 load = 0, hdrtime; + + /* TODO: this could be part of tx_status handling, so that the number + * of retries would be known; TX rate should in that case be stored + * somewhere with the packet */ + + /* Estimate total channel use caused by this frame */ + + /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values, + * 1 usec = 1/8 * (1080 / 10) = 13.5 */ + + if (mode->mode == MODE_IEEE80211A || + mode->mode == MODE_ATHEROS_TURBO || + mode->mode == MODE_ATHEROS_TURBOG || + (mode->mode == MODE_IEEE80211G && + tx->u.tx.rate->flags & IEEE80211_RATE_ERP)) + hdrtime = CHAN_UTIL_HDR_SHORT; + else + hdrtime = CHAN_UTIL_HDR_LONG; + + load = hdrtime; + if (!is_multicast_ether_addr(hdr->addr1)) + load += hdrtime; + + if (tx->u.tx.control->flags & IEEE80211_TXCTL_USE_RTS_CTS) + load += 2 * hdrtime; + else if (tx->u.tx.control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT) + load += hdrtime; + + load += skb->len * tx->u.tx.rate->rate_inv; + + if (tx->u.tx.extra_frag) { + int i; + for (i = 0; i < tx->u.tx.num_extra_frag; i++) { + load += 2 * hdrtime; + load += tx->u.tx.extra_frag[i]->len * + tx->u.tx.rate->rate; + } + } + + /* Divide channel_use by 8 to avoid wrapping around the counter */ + load >>= CHAN_UTIL_SHIFT; + local->channel_use_raw += load; + if (tx->sta) + tx->sta->channel_use_raw += load; + tx->sdata->channel_use_raw += load; + + return TXRX_CONTINUE; +} + +/* TODO: implement register/unregister functions for adding TX/RX handlers + * into ordered list */ + +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_fragment, + ieee80211_tx_h_tkip_encrypt, + ieee80211_tx_h_ccmp_encrypt, + ieee80211_tx_h_wep_encrypt, + ieee80211_tx_h_rate_ctrl, + ieee80211_tx_h_misc, + ieee80211_tx_h_load_stats, + NULL +}; + +/* actual transmit path */ + +/* + * deal with packet injection down monitor interface + * with Radiotap Header -- only called for monitor mode interface + */ +static ieee80211_txrx_result +__ieee80211_parse_tx_radiotap( + struct ieee80211_txrx_data *tx, + struct sk_buff *skb, struct ieee80211_tx_control *control) +{ + /* + * 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_hw_mode *mode = tx->local->hw.conf.mode; + int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len); + + /* + * default control situation for all injected packets + * FIXME: this does not suit all usage cases, expand to allow control + */ + + control->retry_limit = 1; /* no retry */ + control->key_idx = -1; /* no encryption key */ + control->flags &= ~(IEEE80211_TXCTL_USE_RTS_CTS | + IEEE80211_TXCTL_USE_CTS_PROTECT); + control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT | + IEEE80211_TXCTL_NO_ACK; + control->antenna_sel_tx = 0; /* default to default antenna */ + + /* + * 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 < mode->num_rates; i++) { + struct ieee80211_rate *r = &mode->rates[i]; + + if (r->rate > target_rate) + continue; + + control->rate = r; + + if (r->flags & IEEE80211_RATE_PREAMBLE2) + control->tx_rate = r->val2; + else + control->tx_rate = r->val; + + /* end on exact match */ + if (r->rate == target_rate) + i = mode->num_rates; + } + break; + + case IEEE80211_RADIOTAP_ANTENNA: + /* + * radiotap uses 0 for 1st ant, mac80211 is 1 for + * 1st ant + */ + control->antenna_sel_tx = (*iterator.this_arg) + 1; + break; + + case IEEE80211_RADIOTAP_DBM_TX_POWER: + control->power_level = *iterator.this_arg; + break; + + 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 TXRX_DROP; + + skb_trim(skb, skb->len - FCS_LEN); + } + break; + + default: + break; + } + } + + if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */ + return TXRX_DROP; + + /* + * remove the radiotap header + * iterator->max_length was sanity-checked against + * skb->len by iterator init + */ + skb_pull(skb, iterator.max_length); + + return TXRX_CONTINUE; +} + +static ieee80211_txrx_result inline +__ieee80211_tx_prepare(struct ieee80211_txrx_data *tx, + struct sk_buff *skb, + struct net_device *dev, + struct ieee80211_tx_control *control) +{ + struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + struct ieee80211_sub_if_data *sdata; + ieee80211_txrx_result res = TXRX_CONTINUE; + + 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->sta = sta_info_get(local, hdr->addr1); + tx->fc = le16_to_cpu(hdr->frame_control); + + /* + * set defaults for things that can be set by + * injected radiotap headers + */ + control->power_level = local->hw.conf.power_level; + control->antenna_sel_tx = local->hw.conf.antenna_sel_tx; + if (local->sta_antenna_sel != STA_ANTENNA_SEL_AUTO && tx->sta) + control->antenna_sel_tx = tx->sta->antenna_sel_tx; + + /* process and remove the injection radiotap header */ + sdata = IEEE80211_DEV_TO_SUB_IF(dev); + if (unlikely(sdata->type == IEEE80211_IF_TYPE_MNTR)) { + if (__ieee80211_parse_tx_radiotap(tx, skb, control) == + TXRX_DROP) { + return TXRX_DROP; + } + /* + * we removed the radiotap header after this point, + * we filled control with what we could use + * set to the actual ieee header now + */ + hdr = (struct ieee80211_hdr *) skb->data; + res = TXRX_QUEUED; /* indication it was monitor packet */ + } + + tx->u.tx.control = control; + tx->u.tx.unicast = !is_multicast_ether_addr(hdr->addr1); + if (is_multicast_ether_addr(hdr->addr1)) + control->flags |= IEEE80211_TXCTL_NO_ACK; + else + control->flags &= ~IEEE80211_TXCTL_NO_ACK; + tx->fragmented = local->fragmentation_threshold < + IEEE80211_MAX_FRAG_THRESHOLD && tx->u.tx.unicast && + skb->len + FCS_LEN > local->fragmentation_threshold && + (!local->ops->set_frag_threshold); + if (!tx->sta) + control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK; + else if (tx->sta->clear_dst_mask) { + control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK; + tx->sta->clear_dst_mask = 0; + } + 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]; + } + control->flags |= IEEE80211_TXCTL_FIRST_FRAGMENT; + + return res; +} + +/* Device in tx->dev has a reference added; use dev_put(tx->dev) when + * finished with it. */ +static int inline ieee80211_tx_prepare(struct ieee80211_txrx_data *tx, + struct sk_buff *skb, + struct net_device *mdev, + struct ieee80211_tx_control *control) +{ + struct ieee80211_tx_packet_data *pkt_data; + struct net_device *dev; + + pkt_data = (struct ieee80211_tx_packet_data *)skb->cb; + dev = dev_get_by_index(pkt_data->ifindex); + if (unlikely(dev && !is_ieee80211_device(dev, mdev))) { + dev_put(dev); + dev = NULL; + } + if (unlikely(!dev)) + return -ENODEV; + __ieee80211_tx_prepare(tx, skb, dev, control); + return 0; +} + +static int __ieee80211_tx(struct ieee80211_local *local, struct sk_buff *skb, + struct ieee80211_txrx_data *tx) +{ + struct ieee80211_tx_control *control = tx->u.tx.control; + int ret, i; + + if (!ieee80211_qdisc_installed(local->mdev) && + __ieee80211_queue_stopped(local, 0)) { + netif_stop_queue(local->mdev); + return IEEE80211_TX_AGAIN; + } + if (skb) { + ieee80211_dump_frame(local->mdev->name, "TX to low-level driver", skb); + ret = local->ops->tx(local_to_hw(local), skb, control); + if (ret) + return IEEE80211_TX_AGAIN; + local->mdev->trans_start = jiffies; + ieee80211_led_tx(local, 1); + } + if (tx->u.tx.extra_frag) { + control->flags &= ~(IEEE80211_TXCTL_USE_RTS_CTS | + IEEE80211_TXCTL_USE_CTS_PROTECT | + IEEE80211_TXCTL_CLEAR_DST_MASK | + IEEE80211_TXCTL_FIRST_FRAGMENT); + for (i = 0; i < tx->u.tx.num_extra_frag; i++) { + if (!tx->u.tx.extra_frag[i]) + continue; + if (__ieee80211_queue_stopped(local, control->queue)) + return IEEE80211_TX_FRAG_AGAIN; + if (i == tx->u.tx.num_extra_frag) { + control->tx_rate = tx->u.tx.last_frag_hwrate; + control->rate = tx->u.tx.last_frag_rate; + if (tx->u.tx.probe_last_frag) + control->flags |= + IEEE80211_TXCTL_RATE_CTRL_PROBE; + else + control->flags &= + ~IEEE80211_TXCTL_RATE_CTRL_PROBE; + } + + ieee80211_dump_frame(local->mdev->name, + "TX to low-level driver", + tx->u.tx.extra_frag[i]); + ret = local->ops->tx(local_to_hw(local), + tx->u.tx.extra_frag[i], + control); + if (ret) + return IEEE80211_TX_FRAG_AGAIN; + local->mdev->trans_start = jiffies; + ieee80211_led_tx(local, 1); + tx->u.tx.extra_frag[i] = NULL; + } + kfree(tx->u.tx.extra_frag); + tx->u.tx.extra_frag = NULL; + } + return IEEE80211_TX_OK; +} + +static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb, + struct ieee80211_tx_control *control, int mgmt) +{ + struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); + struct sta_info *sta; + ieee80211_tx_handler *handler; + struct ieee80211_txrx_data tx; + ieee80211_txrx_result res = TXRX_DROP, res_prepare; + int ret, i; + + WARN_ON(__ieee80211_queue_pending(local, control->queue)); + + if (unlikely(skb->len < 10)) { + dev_kfree_skb(skb); + return 0; |