diff options
Diffstat (limited to 'net/mac80211/ieee80211.c')
-rw-r--r-- | net/mac80211/ieee80211.c | 4970 |
1 files changed, 4970 insertions, 0 deletions
diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c new file mode 100644 index 00000000000..48a832d4e17 --- /dev/null +++ b/net/mac80211/ieee80211.c @@ -0,0 +1,4970 @@ +/* + * Copyright 2002-2005, Instant802 Networks, Inc. + * Copyright 2005-2006, Devicescape Software, Inc. + * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> + * + * 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 <net/mac80211.h> +#include <net/ieee80211_radiotap.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/netdevice.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/skbuff.h> +#include <linux/etherdevice.h> +#include <linux/if_arp.h> +#include <linux/wireless.h> +#include <linux/rtnetlink.h> +#include <net/iw_handler.h> +#include <linux/compiler.h> +#include <linux/bitmap.h> +#include <net/cfg80211.h> + +#include "ieee80211_common.h" +#include "ieee80211_i.h" +#include "ieee80211_rate.h" +#include "wep.h" +#include "wpa.h" +#include "tkip.h" +#include "wme.h" +#include "aes_ccm.h" +#include "ieee80211_led.h" +#include "ieee80211_cfg.h" + +/* privid for wiphys to determine whether they belong to us or not */ +void *mac80211_wiphy_privid = &mac80211_wiphy_privid; + +/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */ +/* Ethernet-II snap header (RFC1042 for most EtherTypes) */ +static const unsigned char rfc1042_header[] = + { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 }; + +/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */ +static const unsigned char bridge_tunnel_header[] = + { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 }; + +/* No encapsulation header if EtherType < 0x600 (=length) */ +static const unsigned char eapol_header[] = + { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x88, 0x8e }; + + +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; +} + +struct ieee80211_key_conf * +ieee80211_key_data2conf(struct ieee80211_local *local, + const struct ieee80211_key *data) +{ + struct ieee80211_key_conf *conf; + + conf = kmalloc(sizeof(*conf) + data->keylen, GFP_ATOMIC); + if (!conf) + return NULL; + + conf->hw_key_idx = data->hw_key_idx; + conf->alg = data->alg; + conf->keylen = data->keylen; + conf->flags = 0; + if (data->force_sw_encrypt) + conf->flags |= IEEE80211_KEY_FORCE_SW_ENCRYPT; + conf->keyidx = data->keyidx; + if (data->default_tx_key) + conf->flags |= IEEE80211_KEY_DEFAULT_TX_KEY; + if (local->default_wep_only) + conf->flags |= IEEE80211_KEY_DEFAULT_WEP_ONLY; + memcpy(conf->key, data->key, data->keylen); + + return conf; +} + +struct ieee80211_key *ieee80211_key_alloc(struct ieee80211_sub_if_data *sdata, + int idx, size_t key_len, gfp_t flags) +{ + struct ieee80211_key *key; + + key = kzalloc(sizeof(struct ieee80211_key) + key_len, flags); + if (!key) + return NULL; + kref_init(&key->kref); + return key; +} + +static void ieee80211_key_release(struct kref *kref) +{ + struct ieee80211_key *key; + + key = container_of(kref, struct ieee80211_key, kref); + if (key->alg == ALG_CCMP) + ieee80211_aes_key_free(key->u.ccmp.tfm); + kfree(key); +} + +void ieee80211_key_free(struct ieee80211_key *key) +{ + if (key) + kref_put(&key->kref, ieee80211_key_release); +} + +static int rate_list_match(const int *rate_list, int rate) +{ + int i; + + if (!rate_list) + return 0; + + for (i = 0; rate_list[i] >= 0; i++) + if (rate_list[i] == rate) + return 1; + + return 0; +} + + +void ieee80211_prepare_rates(struct ieee80211_local *local, + struct ieee80211_hw_mode *mode) +{ + int i; + + for (i = 0; i < mode->num_rates; i++) { + struct ieee80211_rate *rate = &mode->rates[i]; + + rate->flags &= ~(IEEE80211_RATE_SUPPORTED | + IEEE80211_RATE_BASIC); + + if (local->supp_rates[mode->mode]) { + if (!rate_list_match(local->supp_rates[mode->mode], + rate->rate)) + continue; + } + + rate->flags |= IEEE80211_RATE_SUPPORTED; + + /* Use configured basic rate set if it is available. If not, + * use defaults that are sane for most cases. */ + if (local->basic_rates[mode->mode]) { + if (rate_list_match(local->basic_rates[mode->mode], + rate->rate)) + rate->flags |= IEEE80211_RATE_BASIC; + } else switch (mode->mode) { + case MODE_IEEE80211A: + if (rate->rate == 60 || rate->rate == 120 || + rate->rate == 240) + rate->flags |= IEEE80211_RATE_BASIC; + break; + case MODE_IEEE80211B: + if (rate->rate == 10 || rate->rate == 20) + rate->flags |= IEEE80211_RATE_BASIC; + break; + case MODE_ATHEROS_TURBO: + if (rate->rate == 120 || rate->rate == 240 || + rate->rate == 480) + rate->flags |= IEEE80211_RATE_BASIC; + break; + case MODE_IEEE80211G: + if (rate->rate == 10 || rate->rate == 20 || + rate->rate == 55 || rate->rate == 110) + rate->flags |= IEEE80211_RATE_BASIC; + break; + } + + /* Set ERP and MANDATORY flags based on phymode */ + switch (mode->mode) { + case MODE_IEEE80211A: + if (rate->rate == 60 || rate->rate == 120 || + rate->rate == 240) + rate->flags |= IEEE80211_RATE_MANDATORY; + break; + case MODE_IEEE80211B: + if (rate->rate == 10) + rate->flags |= IEEE80211_RATE_MANDATORY; + break; + case MODE_ATHEROS_TURBO: + break; + case MODE_IEEE80211G: + if (rate->rate == 10 || rate->rate == 20 || + rate->rate == 55 || rate->rate == 110 || + rate->rate == 60 || rate->rate == 120 || + rate->rate == 240) + rate->flags |= IEEE80211_RATE_MANDATORY; + break; + } + if (ieee80211_is_erp_rate(mode->mode, rate->rate)) + rate->flags |= IEEE80211_RATE_ERP; + } +} + + +static void ieee80211_key_threshold_notify(struct net_device *dev, + struct ieee80211_key *key, + struct sta_info *sta) +{ + struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); + struct sk_buff *skb; + struct ieee80211_msg_key_notification *msg; + + /* if no one will get it anyway, don't even allocate it. + * unlikely because this is only relevant for APs + * where the device must be open... */ + if (unlikely(!local->apdev)) + return; + + skb = dev_alloc_skb(sizeof(struct ieee80211_frame_info) + + sizeof(struct ieee80211_msg_key_notification)); + if (!skb) + return; + + skb_reserve(skb, sizeof(struct ieee80211_frame_info)); + msg = (struct ieee80211_msg_key_notification *) + skb_put(skb, sizeof(struct ieee80211_msg_key_notification)); + msg->tx_rx_count = key->tx_rx_count; + memcpy(msg->ifname, dev->name, IFNAMSIZ); + if (sta) + memcpy(msg->addr, sta->addr, ETH_ALEN); + else + memset(msg->addr, 0xff, ETH_ALEN); + + key->tx_rx_count = 0; + + ieee80211_rx_mgmt(local, skb, NULL, + ieee80211_msg_key_threshold_notification); +} + + +static u8 * ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len) +{ + u16 fc; + + if (len < 24) + return NULL; + + fc = le16_to_cpu(hdr->frame_control); + + switch (fc & IEEE80211_FCTL_FTYPE) { + case IEEE80211_FTYPE_DATA: + switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) { + case IEEE80211_FCTL_TODS: + return hdr->addr1; + case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS): + return NULL; + case IEEE80211_FCTL_FROMDS: + return hdr->addr2; + case 0: + return hdr->addr3; + } + break; + case IEEE80211_FTYPE_MGMT: + return hdr->addr3; + case IEEE80211_FTYPE_CTL: + if ((fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL) + return hdr->addr1; + else + return NULL; + } + + return NULL; +} + +int ieee80211_get_hdrlen(u16 fc) +{ + int hdrlen = 24; + + switch (fc & IEEE80211_FCTL_FTYPE) { + case IEEE80211_FTYPE_DATA: + if ((fc & IEEE80211_FCTL_FROMDS) && (fc & IEEE80211_FCTL_TODS)) + hdrlen = 30; /* Addr4 */ + /* + * The QoS Control field is two bytes and its presence is + * indicated by the IEEE80211_STYPE_QOS_DATA bit. Add 2 to + * hdrlen if that bit is set. + * This works by masking out the bit and shifting it to + * bit position 1 so the result has the value 0 or 2. + */ + hdrlen += (fc & IEEE80211_STYPE_QOS_DATA) + >> (ilog2(IEEE80211_STYPE_QOS_DATA)-1); + break; + case IEEE80211_FTYPE_CTL: + /* + * ACK and CTS are 10 bytes, all others 16. To see how + * to get this condition consider + * subtype mask: 0b0000000011110000 (0x00F0) + * ACK subtype: 0b0000000011010000 (0x00D0) + * CTS subtype: 0b0000000011000000 (0x00C0) + * bits that matter: ^^^ (0x00E0) + * value of those: 0b0000000011000000 (0x00C0) + */ + if ((fc & 0xE0) == 0xC0) + hdrlen = 10; + else + hdrlen = 16; + break; + } + + return hdrlen; +} +EXPORT_SYMBOL(ieee80211_get_hdrlen); + +int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb) +{ + const struct ieee80211_hdr *hdr = (const struct ieee80211_hdr *) skb->data; + int hdrlen; + + if (unlikely(skb->len < 10)) + return 0; + hdrlen = ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control)); + if (unlikely(hdrlen > skb->len)) + return 0; + return hdrlen; +} +EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb); + +static int ieee80211_get_radiotap_len(struct sk_buff *skb) +{ + struct ieee80211_radiotap_header *hdr = + (struct ieee80211_radiotap_header *) skb->data; + + return le16_to_cpu(hdr->it_len); +} + +#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 int ieee80211_is_eapol(const struct sk_buff *skb) +{ + const struct ieee80211_hdr *hdr; + u16 fc; + int hdrlen; + + if (unlikely(skb->len < 10)) + return 0; + + hdr = (const struct ieee80211_hdr *) skb->data; + fc = le16_to_cpu(hdr->frame_control); + + if (unlikely(!WLAN_FC_DATA_PRESENT(fc))) + return 0; + + hdrlen = ieee80211_get_hdrlen(fc); + + if (unlikely(skb->len >= hdrlen + sizeof(eapol_header) && + memcmp(skb->data + hdrlen, eapol_header, + sizeof(eapol_header)) == 0)) + return 1; + + return 0; +} + + +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->local->cts_protect_erp_frames && 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_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->hw.extra_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->hw.extra_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; +} + + +void ieee80211_tx_set_iswep(struct ieee80211_txrx_data *tx) +{ + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data; + + hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); + if (tx->u.tx.extra_frag) { + struct ieee80211_hdr *fhdr; + int i; + for (i = 0; i < tx->u.tx.num_extra_frag; i++) { + fhdr = (struct ieee80211_hdr *) + tx->u.tx.extra_frag[i]->data; + fhdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); + } + } +} + + +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 int ieee80211_frame_duration(struct ieee80211_local *local, size_t len, + int rate, int erp, int short_preamble) +{ + int dur; + + /* calculate duration (in microseconds, rounded up to next higher + * integer if it includes a fractional microsecond) to send frame of + * len bytes (does not include FCS) at the given rate. Duration will + * also include SIFS. + * + * rate is in 100 kbps, so divident is multiplied by 10 in the + * DIV_ROUND_UP() operations. + */ + + if (local->hw.conf.phymode == MODE_IEEE80211A || erp || + local->hw.conf.phymode == MODE_ATHEROS_TURBO) { + /* + * OFDM: + * + * N_DBPS = DATARATE x 4 + * N_SYM = Ceiling((16+8xLENGTH+6) / N_DBPS) + * (16 = SIGNAL time, 6 = tail bits) + * TXTIME = T_PREAMBLE + T_SIGNAL + T_SYM x N_SYM + Signal Ext + * + * T_SYM = 4 usec + * 802.11a - 17.5.2: aSIFSTime = 16 usec + * 802.11g - 19.8.4: aSIFSTime = 10 usec + + * signal ext = 6 usec + */ + /* FIX: Atheros Turbo may have different (shorter) duration? */ + dur = 16; /* SIFS + signal ext */ + dur += 16; /* 17.3.2.3: T_PREAMBLE = 16 usec */ + dur += 4; /* 17.3.2.3: T_SIGNAL = 4 usec */ + dur += 4 * DIV_ROUND_UP((16 + 8 * (len + 4) + 6) * 10, + 4 * rate); /* T_SYM x N_SYM */ + } else { + /* + * 802.11b or 802.11g with 802.11b compatibility: + * 18.3.4: TXTIME = PreambleLength + PLCPHeaderTime + + * Ceiling(((LENGTH+PBCC)x8)/DATARATE). PBCC=0. + * + * 802.11 (DS): 15.3.3, 802.11b: 18.3.4 + * aSIFSTime = 10 usec + * aPreambleLength = 144 usec or 72 usec with short preamble + * aPLCPHeaderLength = 48 usec or 24 usec with short preamble + */ + dur = 10; /* aSIFSTime = 10 usec */ + dur += short_preamble ? (72 + 24) : (144 + 48); + + dur += DIV_ROUND_UP(8 * (len + 4) * 10, rate); + } + + return dur; +} + + +/* Exported duration function for driver use */ +__le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw, + size_t frame_len, int rate) +{ + struct ieee80211_local *local = hw_to_local(hw); + u16 dur; + int erp; + + erp = ieee80211_is_erp_rate(hw->conf.phymode, rate); + dur = ieee80211_frame_duration(local, frame_len, rate, + erp, local->short_preamble); + + return cpu_to_le16(dur); +} +EXPORT_SYMBOL(ieee80211_generic_frame_duration); + + +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 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->local->cts_protect_erp_frames && + !(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_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; + |