C++ IEEE80211_SKB_CB函数代码示例

static void _rtl_tx_complete(struct urb *urb)
{
	struct sk_buff *skb = (struct sk_buff *)urb->context;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	struct rtl_usb *rtlusb = (struct rtl_usb *)info->rate_driver_data[0];
	struct ieee80211_hw *hw = usb_get_intfdata(rtlusb->intf);
	int err;

	if (unlikely(IS_USB_STOP(rtlusb)))
		return;
	err = _usb_tx_post(hw, urb, skb);
	if (err) {
		/* Ignore error and keep issuiing other urbs */
		return;
	}
}

/*  Headroom is not adjusted.  Caller should ensure that skb has sufficient
 *  headroom in case the frame is encrypted. */
static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
		struct sk_buff *skb)
{
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);

	skb_set_mac_header(skb, 0);
	skb_set_network_header(skb, 0);
	skb_set_transport_header(skb, 0);

	/* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
	skb_set_queue_mapping(skb, IEEE80211_AC_VO);
	skb->priority = 7;

	info->control.vif = &sdata->vif;
	ieee80211_set_qos_hdr(sdata, skb);
}

static void p54spi_op_tx(struct ieee80211_hw *dev, struct sk_buff *skb)
{
	struct p54s_priv *priv = dev->priv;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	struct p54_tx_info *mi = (struct p54_tx_info *) info->rate_driver_data;
	struct p54s_tx_info *di = (struct p54s_tx_info *) mi->data;
	unsigned long flags;

	BUILD_BUG_ON(sizeof(*di) > sizeof((mi->data)));

	spin_lock_irqsave(&priv->tx_lock, flags);
	list_add_tail(&di->tx_list, &priv->tx_pending);
	spin_unlock_irqrestore(&priv->tx_lock, flags);

	ieee80211_queue_work(priv->hw, &priv->work);
}

/**
 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
 *
 * @skb: 802.11 frame to be sent
 * @sdata: network subif the frame will be sent through
 *
 * Lookup next hop for given skb and start path discovery if no
 * forwarding information is found.
 *
 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
 * skb is freeed here if no mpath could be allocated.
 */
int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
			 struct sk_buff *skb)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	struct mesh_path *mpath;
	struct sk_buff *skb_to_free = NULL;
	u8 *target_addr = hdr->addr3;
	int err = 0;

	/* Nulls are only sent to peers for PS and should be pre-addressed */
	if (ieee80211_is_qos_nullfunc(hdr->frame_control))
		return 0;

	rcu_read_lock();
	err = mesh_nexthop_lookup(sdata, skb);
	if (!err)
		goto endlookup;

	/* no nexthop found, start resolving */
	mpath = mesh_path_lookup(sdata, target_addr);
	if (!mpath) {
		mpath = mesh_path_add(sdata, target_addr);
		if (IS_ERR(mpath)) {
			mesh_path_discard_frame(sdata, skb);
			err = PTR_ERR(mpath);
			goto endlookup;
		}
	}

	if (!(mpath->flags & MESH_PATH_RESOLVING))
		mesh_queue_preq(mpath, PREQ_Q_F_START);

	if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
		skb_to_free = skb_dequeue(&mpath->frame_queue);

	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
	ieee80211_set_qos_hdr(sdata, skb);
	skb_queue_tail(&mpath->frame_queue, skb);
	err = -ENOENT;
	if (skb_to_free)
		mesh_path_discard_frame(sdata, skb_to_free);

endlookup:
	rcu_read_unlock();
	return err;
}

/**
 * tx_urb_complete - completes the execution of an URB
 * @urb: a URB
 *
 * This function is called if the URB has been transferred to a device or an
 * error has happened.
 */
static void tx_urb_complete(struct urb *urb)
{
	int r;
	struct sk_buff *skb;
	struct ieee80211_tx_info *info;
	struct zd_usb *usb;
	struct zd_usb_tx *tx;

	skb = (struct sk_buff *)urb->context;
	info = IEEE80211_SKB_CB(skb);
	/*
	 * grab 'usb' pointer before handing off the skb (since
	 * it might be freed by zd_mac_tx_to_dev or mac80211)
	 */
	usb = &zd_hw_mac(info->rate_driver_data[0])->chip.usb;
	tx = &usb->tx;

	switch (urb->status) {
	case 0:
		break;
	case -ESHUTDOWN:
	case -EINVAL:
	case -ENODEV:
	case -ENOENT:
	case -ECONNRESET:
	case -EPIPE:
		dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
		break;
	default:
		dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
		goto resubmit;
	}
free_urb:
	skb_unlink(skb, &usb->tx.submitted_skbs);
	zd_mac_tx_to_dev(skb, urb->status);
	usb_free_urb(urb);
	tx_dec_submitted_urbs(usb);
	return;
resubmit:
	usb_anchor_urb(urb, &tx->submitted);
	r = usb_submit_urb(urb, GFP_ATOMIC);
	if (r) {
		usb_unanchor_urb(urb);
		dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
		goto free_urb;
	}
}

static void rt2x00queue_create_tx_descriptor_seq(struct rt2x00_dev *rt2x00dev,
						 struct sk_buff *skb,
						 struct txentry_desc *txdesc)
{
	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
	struct rt2x00_intf *intf = vif_to_intf(tx_info->control.vif);
	u16 seqno;

	if (!(tx_info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ))
		return;

	__set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);

	if (!test_bit(REQUIRE_SW_SEQNO, &rt2x00dev->cap_flags)) {
		/*
		 * rt2800 has a H/W (or F/W) bug, device incorrectly increase
		 * seqno on retransmited data (non-QOS) frames. To workaround
		 * the problem let's generate seqno in software if QOS is
		 * disabled.
		 */
		if (test_bit(CONFIG_QOS_DISABLED, &rt2x00dev->flags))
			__clear_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
		else
			/* H/W will generate sequence number */
			return;
	}

	/*
	 * The hardware is not able to insert a sequence number. Assign a
	 * software generated one here.
	 *
	 * This is wrong because beacons are not getting sequence
	 * numbers assigned properly.
	 *
	 * A secondary problem exists for drivers that cannot toggle
	 * sequence counting per-frame, since those will override the
	 * sequence counter given by mac80211.
	 */
	if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags))
		seqno = atomic_add_return(0x10, &intf->seqno);
	else
		seqno = atomic_read(&intf->seqno);

	hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
	hdr->seq_ctrl |= cpu_to_le16(seqno);
}

static int ath9k_send_nullfunc(struct ath_wiphy *aphy,
			       struct ieee80211_vif *vif, const u8 *bssid,
			       int ps)
{
	struct ath_softc *sc = aphy->sc;
	struct ath_tx_control txctl;
	struct sk_buff *skb;
	struct ieee80211_hdr *hdr;
	__le16 fc;
	struct ieee80211_tx_info *info;

	skb = dev_alloc_skb(24);
	if (skb == NULL)
		return -ENOMEM;
	hdr = (struct ieee80211_hdr *) skb_put(skb, 24);
	memset(hdr, 0, 24);
	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC |
			 IEEE80211_FCTL_TODS);
	if (ps)
		fc |= cpu_to_le16(IEEE80211_FCTL_PM);
	hdr->frame_control = fc;
	memcpy(hdr->addr1, bssid, ETH_ALEN);
	memcpy(hdr->addr2, aphy->hw->wiphy->perm_addr, ETH_ALEN);
	memcpy(hdr->addr3, bssid, ETH_ALEN);

	info = IEEE80211_SKB_CB(skb);
	memset(info, 0, sizeof(*info));
	info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS;
	info->control.vif = vif;
	info->control.rates[0].idx = 0;
	info->control.rates[0].count = 4;
	info->control.rates[1].idx = -1;

	memset(&txctl, 0, sizeof(struct ath_tx_control));
	txctl.txq = &sc->tx.txq[sc->tx.hwq_map[ATH9K_WME_AC_VO]];
	txctl.frame_type = ps ? ATH9K_INT_PAUSE : ATH9K_INT_UNPAUSE;

	if (ath_tx_start(aphy->hw, skb, &txctl) != 0)
		goto exit;

	return 0;
exit:
	dev_kfree_skb_any(skb);
	return -1;
}

static int pio_tx_frame(struct b43_pio_txqueue *q,
			struct sk_buff *skb)
{
	struct b43_wldev *dev = q->dev;
	struct b43_wl *wl = dev->wl;
	struct b43_pio_txpacket *pack;
	u16 cookie;
	int err;
	unsigned int hdrlen;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);

	B43_WARN_ON(list_empty(&q->packets_list));
	pack = list_entry(q->packets_list.next,
			  struct b43_pio_txpacket, list);

	cookie = generate_cookie(q, pack);
	hdrlen = b43_txhdr_size(dev);
	err = b43_generate_txhdr(dev, (u8 *)&wl->txhdr, skb,
				 info, cookie);
	if (err)
		return err;

	if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
		/* Tell the firmware about the cookie of the last
		 * mcast frame, so it can clear the more-data bit in it. */
		b43_shm_write16(dev, B43_SHM_SHARED,
				B43_SHM_SH_MCASTCOOKIE, cookie);
	}

	pack->skb = skb;
	if (q->rev >= 8)
		pio_tx_frame_4byte_queue(pack, (const u8 *)&wl->txhdr, hdrlen);
	else
		pio_tx_frame_2byte_queue(pack, (const u8 *)&wl->txhdr, hdrlen);

	/* Remove it from the list of available packet slots.
	 * It will be put back when we receive the status report. */
	list_del(&pack->list);

	/* Update the queue statistics. */
	q->buffer_used += roundup(skb->len + hdrlen, 4);
	q->free_packet_slots -= 1;

	return 0;
}

static void brcms_ops_tx(struct ieee80211_hw *hw,
			 struct ieee80211_tx_control *control,
			 struct sk_buff *skb)
{
	struct brcms_info *wl = hw->priv;
	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);

	spin_lock_bh(&wl->lock);
	if (!wl->pub->up) {
		brcms_err(wl->wlc->hw->d11core, "ops->tx called while down\n");
		kfree_skb(skb);
		goto done;
	}
	if (brcms_c_sendpkt_mac80211(wl->wlc, skb, hw))
		tx_info->rate_driver_data[0] = control->sta;
 done:
	spin_unlock_bh(&wl->lock);
}

/**
 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
 *
 * @skb: 802.11 frame to be sent
 * @sdata: network subif the frame will be sent through
 *
 * Lookup next hop for given skb and start path discovery if no
 * forwarding information is found.
 *
 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
 * skb is freeed here if no mpath could be allocated.
 */
int mesh_nexthop_resolve(struct sk_buff *skb,
			 struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	struct mesh_path *mpath;
	struct sk_buff *skb_to_free = NULL;
	u8 *target_addr = hdr->addr3;
	int err = 0;

	rcu_read_lock();
	err = mesh_nexthop_lookup(skb, sdata);
	if (!err)
		goto endlookup;

	/* no nexthop found, start resolving */
	mpath = mesh_path_lookup(target_addr, sdata);
	if (!mpath) {
		mesh_path_add(target_addr, sdata);
		mpath = mesh_path_lookup(target_addr, sdata);
		if (!mpath) {
			mesh_path_discard_frame(skb, sdata);
			err = -ENOSPC;
			goto endlookup;
		}
	}

	if (!(mpath->flags & MESH_PATH_RESOLVING))
		mesh_queue_preq(mpath, PREQ_Q_F_START);

	if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
		skb_to_free = skb_dequeue(&mpath->frame_queue);

	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
	ieee80211_set_qos_hdr(sdata, skb);
	skb_queue_tail(&mpath->frame_queue, skb);
	err = -ENOENT;
	if (skb_to_free)
		mesh_path_discard_frame(skb_to_free, sdata);

endlookup:
	rcu_read_unlock();
	return err;
}

static int pio_tx_frame(struct b43_pio_txqueue *q,
			struct sk_buff *skb)
{
	struct b43_wldev *dev = q->dev;
	struct b43_wl *wl = dev->wl;
	struct b43_pio_txpacket *pack;
	u16 cookie;
	int err;
	unsigned int hdrlen;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	struct b43_txhdr *txhdr = (struct b43_txhdr *)wl->pio_scratchspace;

	B43_WARN_ON(list_empty(&q->packets_list));
	pack = list_entry(q->packets_list.next,
			  struct b43_pio_txpacket, list);

	cookie = generate_cookie(q, pack);
	hdrlen = b43_txhdr_size(dev);
	BUILD_BUG_ON(sizeof(wl->pio_scratchspace) < sizeof(struct b43_txhdr));
	B43_WARN_ON(sizeof(wl->pio_scratchspace) < hdrlen);
	err = b43_generate_txhdr(dev, (u8 *)txhdr, skb,
				 info, cookie);
	if (err)
		return err;

	if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
		b43_shm_write16(dev, B43_SHM_SHARED,
				B43_SHM_SH_MCASTCOOKIE, cookie);
	}

	pack->skb = skb;
	if (q->rev >= 8)
		pio_tx_frame_4byte_queue(pack, (const u8 *)txhdr, hdrlen);
	else
		pio_tx_frame_2byte_queue(pack, (const u8 *)txhdr, hdrlen);

	list_del(&pack->list);

	
	q->buffer_used += roundup(skb->len + hdrlen, 4);
	q->free_packet_slots -= 1;

	return 0;
}

ieee80211_tx_result
ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
{
	struct sk_buff *skb = tx->skb;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	struct ieee80211_key *key = tx->key;
	struct ieee80211_mmie *mmie;
	u8 *pn, aad[20];
	int i;

	if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
		/* hwaccel */
		info->control.hw_key = &tx->key->conf;
		return 0;
	}

	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
		return TX_DROP;

	mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
	mmie->element_id = WLAN_EID_MMIE;
	mmie->length = sizeof(*mmie) - 2;
	mmie->key_id = cpu_to_le16(key->conf.keyidx);

	/* PN = PN + 1 */
	pn = key->u.aes_cmac.tx_pn;

	for (i = sizeof(key->u.aes_cmac.tx_pn) - 1; i >= 0; i--) {
		pn[i]++;
		if (pn[i])
			break;
	}
	bip_ipn_swap(mmie->sequence_number, pn);

	bip_aad(skb, aad);

	/*
	 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
	 */
	ieee80211_aes_cmac(key->u.aes_cmac.tfm, key->u.aes_cmac.tx_crypto_buf,
			   aad, skb->data + 24, skb->len - 24, mmie->mic);

	return TX_CONTINUE;
}

static void mac80211_hwsim_beacon_tx(void *arg, u8 *mac,
				     struct ieee80211_vif *vif)
{
	struct ieee80211_hw *hw = arg;
	struct sk_buff *skb;
	struct ieee80211_tx_info *info;

	if (vif->type != IEEE80211_IF_TYPE_AP)
		return;

	skb = ieee80211_beacon_get(hw, vif);
	if (skb == NULL)
		return;
	info = IEEE80211_SKB_CB(skb);

	mac80211_hwsim_monitor_rx(hw, skb);
	mac80211_hwsim_tx_frame(hw, skb);
	dev_kfree_skb(skb);
}

/*  Headroom is not adjusted.  Caller should ensure that skb has sufficient
 *  headroom in case the frame is encrypted. */
static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
		struct sk_buff *skb)
{
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;

	skb_reset_mac_header(skb);
	skb_reset_network_header(skb);
	skb_reset_transport_header(skb);

	/* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
	skb_set_queue_mapping(skb, IEEE80211_AC_VO);
	skb->priority = 7;

	info->control.vif = &sdata->vif;
	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
	ieee80211_set_qos_hdr(sdata, skb);
	ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
}

/**
 * ieee80211_set_qos_hdr - Fill in the QoS header if there is one.
 *
 * @sdata: local subif
 * @skb: packet to be updated
 */
void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata,
			   struct sk_buff *skb)
{
	struct ieee80211_hdr *hdr = (void *)skb->data;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
	u8 flags;
	u8 *p;

	if (!ieee80211_is_data_qos(hdr->frame_control))
		return;

	p = ieee80211_get_qos_ctl(hdr);

	/* set up the first byte */

	/*
	 * preserve everything but the TID and ACK policy
	 * (which we both write here)
	 */
	flags = *p & ~(IEEE80211_QOS_CTL_TID_MASK |
		       IEEE80211_QOS_CTL_ACK_POLICY_MASK);

	if (is_multicast_ether_addr(hdr->addr1) ||
	    sdata->noack_map & BIT(tid)) {
		flags |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK;
		info->flags |= IEEE80211_TX_CTL_NO_ACK;
	}

	*p = flags | tid;

	/* set up the second byte */
	p++;

	if (ieee80211_vif_is_mesh(&sdata->vif)) {
		/* preserve RSPI and Mesh PS Level bit */
		*p &= ((IEEE80211_QOS_CTL_RSPI |
			IEEE80211_QOS_CTL_MESH_PS_LEVEL) >> 8);

		/* Nulls don't have a mesh header (frame body) */
		if (!ieee80211_is_qos_nullfunc(hdr->frame_control))
			*p |= (IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8);
	} else {