// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright(c) 2003 - 2004 Intel Corporation. All rights reserved.
 *
 * Contact Information:
 * James P. Ketrenos <ipw2100-admin@linux.intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 * Few modifications for Realtek's Wi-Fi drivers by
 * Andrea Merello <andrea.merello@gmail.com>
 *
 * A special thanks goes to Realtek for their support !
 */
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/if_arp.h>
#include <linux/in6.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/pci.h>
#include <linux/proc_fs.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/tcp.h>
#include <linux/types.h>
#include <linux/wireless.h>
#include <linux/etherdevice.h>
#include <linux/uaccess.h>
#include <linux/if_vlan.h>

#include "rtllib.h"

/* 802.11 Data Frame
 *
 *
 * 802.11 frame_control for data frames - 2 bytes
 *      ,--------------------------------------------------------------------.
 * bits | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |  9 |  a |  b  |  c  |  d  | e  |
 *      |---|---|---|---|---|---|---|---|---|----|----|-----|-----|-----|----|
 * val  | 0 | 0 | 0 | 1 | x | 0 | 0 | 0 | 1 |  0 |  x |  x  |  x  |  x  | x  |
 *      |---|---|---|---|---|---|---|---|---|----|----|-----|-----|-----|----|
 * desc |  ver  | type  |  ^-subtype-^  |to |from|more|retry| pwr |more |wep |
 *      |       |       | x=0 data      |DS | DS |frag|     | mgm |data |    |
 *      |       |       | x=1 data+ack  |   |    |    |     |     |     |    |
 *      '--------------------------------------------------------------------'
 *                                           /\
 *                                           |
 * 802.11 Data Frame                         |
 *          ,--------- 'ctrl' expands to >---'
 *          |
 *       ,--'---,-------------------------------------------------------------.
 * Bytes |  2   |  2   |    6    |    6    |    6    |  2   | 0..2312 |   4  |
 *       |------|------|---------|---------|---------|------|---------|------|
 * Desc. | ctrl | dura |  DA/RA  |   TA    |    SA   | Sequ |  Frame  |  fcs |
 *       |      | tion | (BSSID) |         |         | ence |  data   |      |
 *       `--------------------------------------------------|         |------'
 * Total: 28 non-data bytes                                 `----.----'
 *                                                               |
 *        .- 'Frame data' expands to <---------------------------'
 *        |
 *        V
 *       ,---------------------------------------------------.
 * Bytes |  1   |  1   |    1    |    3     |  2   |  0-2304 |
 *       |------|------|---------|----------|------|---------|
 * Desc. | SNAP | SNAP | Control |Eth Tunnel| Type | IP      |
 *       | DSAP | SSAP |         |          |      | Packet  |
 *       | 0xAA | 0xAA |0x03 (UI)|0x00-00-F8|      |         |
 *       `-----------------------------------------|         |
 * Total: 8 non-data bytes                         `----.----'
 *                                                      |
 *        .- 'IP Packet' expands, if WEP enabled, to <--'
 *        |
 *        V
 *       ,-----------------------.
 * Bytes |  4  |   0-2296  |  4  |
 *       |-----|-----------|-----|
 * Desc. | IV  | Encrypted | ICV |
 *       |     | IP Packet |     |
 *       `-----------------------'
 * Total: 8 non-data bytes
 *
 *
 * 802.3 Ethernet Data Frame
 *
 *       ,-----------------------------------------.
 * Bytes |   6   |   6   |  2   |  Variable |   4  |
 *       |-------|-------|------|-----------|------|
 * Desc. | Dest. | Source| Type | IP Packet |  fcs |
 *       |  MAC  |  MAC  |      |          |      |
 *       `-----------------------------------------'
 * Total: 18 non-data bytes
 *
 * In the event that fragmentation is required, the incoming payload is split
 * into N parts of size ieee->fts.  The first fragment contains the SNAP header
 * and the remaining packets are just data.
 *
 * If encryption is enabled, each fragment payload size is reduced by enough
 * space to add the prefix and postfix (IV and ICV totalling 8 bytes in
 * the case of WEP) So if you have 1500 bytes of payload with ieee->fts set to
 * 500 without encryption it will take 3 frames.  With WEP it will take 4 frames
 * as the payload of each frame is reduced to 492 bytes.
 *
 * SKB visualization
 *
 * ,- skb->data
 * |
 * |    ETHERNET HEADER        ,-<-- PAYLOAD
 * |                           |     14 bytes from skb->data
 * |  2 bytes for Type --> ,T. |     (sizeof ethhdr)
 * |                       | | |
 * |,-Dest.--. ,--Src.---. | | |
 * |  6 bytes| | 6 bytes | | | |
 * v         | |         | | | |
 * 0         | v       1 | v | v           2
 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
 *     ^     | ^         | ^ |
 *     |     | |         | | |
 *     |     | |         | `T' <---- 2 bytes for Type
 *     |     | |         |
 *     |     | '---SNAP--' <-------- 6 bytes for SNAP
 *     |     |
 *     `-IV--' <-------------------- 4 bytes for IV (WEP)
 *
 *      SNAP HEADER
 *
 */

static u8 P802_1H_OUI[P80211_OUI_LEN] = { 0x00, 0x00, 0xf8 };
static u8 RFC1042_OUI[P80211_OUI_LEN] = { 0x00, 0x00, 0x00 };

static int rtllib_put_snap(u8 *data, u16 h_proto)
{
        struct rtllib_snap_hdr *snap;
        u8 *oui;

        snap = (struct rtllib_snap_hdr *)data;
        snap->dsap = 0xaa;
        snap->ssap = 0xaa;
        snap->ctrl = 0x03;

        if (h_proto == 0x8137 || h_proto == 0x80f3)
                oui = P802_1H_OUI;
        else
                oui = RFC1042_OUI;
        snap->oui[0] = oui[0];
        snap->oui[1] = oui[1];
        snap->oui[2] = oui[2];

        *(__be16 *)(data + SNAP_SIZE) = htons(h_proto);

        return SNAP_SIZE + sizeof(u16);
}

int rtllib_encrypt_fragment(struct rtllib_device *ieee, struct sk_buff *frag,
                            int hdr_len)
{
        struct lib80211_crypt_data *crypt = NULL;
        int res;

        crypt = ieee->crypt_info.crypt[ieee->crypt_info.tx_keyidx];

        if (!(crypt && crypt->ops)) {
                netdev_info(ieee->dev, "=========>%s(), crypt is null\n",
                            __func__);
                return -1;
        }
        /* To encrypt, frame format is:
         * IV (4 bytes), clear payload (including SNAP), ICV (4 bytes)
         */

        /* Host-based IEEE 802.11 fragmentation for TX is not yet supported, so
         * call both MSDU and MPDU encryption functions from here.
         */
        atomic_inc(&crypt->refcnt);
        res = 0;
        if (crypt->ops->encrypt_msdu)
                res = crypt->ops->encrypt_msdu(frag, hdr_len, crypt->priv);
        if (res == 0 && crypt->ops->encrypt_mpdu)
                res = crypt->ops->encrypt_mpdu(frag, hdr_len, crypt->priv);

        atomic_dec(&crypt->refcnt);
        if (res < 0) {
                netdev_info(ieee->dev, "%s: Encryption failed: len=%d.\n",
                            ieee->dev->name, frag->len);
                return -1;
        }

        return 0;
}


void rtllib_txb_free(struct rtllib_txb *txb)
{
        if (unlikely(!txb))
                return;
        kfree(txb);
}

static struct rtllib_txb *rtllib_alloc_txb(int nr_frags, int txb_size,
                                           gfp_t gfp_mask)
{
        struct rtllib_txb *txb;
        int i;

        txb = kmalloc(sizeof(struct rtllib_txb) + (sizeof(u8 *) * nr_frags),
                      gfp_mask);
        if (!txb)
                return NULL;

        memset(txb, 0, sizeof(struct rtllib_txb));
        txb->nr_frags = nr_frags;
        txb->frag_size = cpu_to_le16(txb_size);

        for (i = 0; i < nr_frags; i++) {
                txb->fragments[i] = dev_alloc_skb(txb_size);
                if (unlikely(!txb->fragments[i])) {
                        i--;
                        break;
                }
                memset(txb->fragments[i]->cb, 0, sizeof(txb->fragments[i]->cb));
        }
        if (unlikely(i != nr_frags)) {
                while (i >= 0)
                        dev_kfree_skb_any(txb->fragments[i--]);
                kfree(txb);
                return NULL;
        }
        return txb;
}

static int rtllib_classify(struct sk_buff *skb, u8 bIsAmsdu)
{
        struct ethhdr *eth;
        struct iphdr *ip;

        eth = (struct ethhdr *)skb->data;
        if (eth->h_proto != htons(ETH_P_IP))
                return 0;

#ifdef VERBOSE_DEBUG
        print_hex_dump_bytes("%s: ", __func__, DUMP_PREFIX_NONE, skb->data,
                             skb->len);
#endif
        ip = ip_hdr(skb);
        switch (ip->tos & 0xfc) {
        case 0x20:
                return 2;
        case 0x40:
                return 1;
        case 0x60:
                return 3;
        case 0x80:
                return 4;
        case 0xa0:
                return 5;
        case 0xc0:
                return 6;
        case 0xe0:
                return 7;
        default:
                return 0;
        }
}

static void rtllib_tx_query_agg_cap(struct rtllib_device *ieee,
                                    struct sk_buff *skb,
                                    struct cb_desc *tcb_desc)
{
        struct rt_hi_throughput *pHTInfo = ieee->pHTInfo;
        struct tx_ts_record *pTxTs = NULL;
        struct rtllib_hdr_1addr *hdr = (struct rtllib_hdr_1addr *)skb->data;

        if (rtllib_act_scanning(ieee, false))
                return;

        if (!pHTInfo->bCurrentHTSupport || !pHTInfo->bEnableHT)
                return;
        if (!IsQoSDataFrame(skb->data))
                return;
        if (is_multicast_ether_addr(hdr->addr1))
                return;

        if (tcb_desc->bdhcp || ieee->CntAfterLink < 2)
                return;

        if (pHTInfo->IOTAction & HT_IOT_ACT_TX_NO_AGGREGATION)
                return;

        if (!ieee->GetNmodeSupportBySecCfg(ieee->dev))
                return;
        if (pHTInfo->bCurrentAMPDUEnable) {
                if (!GetTs(ieee, (struct ts_common_info **)(&pTxTs), hdr->addr1,
                    skb->priority, TX_DIR, true)) {
                        netdev_info(ieee->dev, "%s: can't get TS\n", __func__);
                        return;
                }
                if (!pTxTs->TxAdmittedBARecord.b_valid) {
                        if (ieee->wpa_ie_len && (ieee->pairwise_key_type ==
                            KEY_TYPE_NA)) {
                                ;
                        } else if (tcb_desc->bdhcp == 1) {
                                ;
                        } else if (!pTxTs->bDisable_AddBa) {
                                TsStartAddBaProcess(ieee, pTxTs);
                        }
                        goto FORCED_AGG_SETTING;
                } else if (!pTxTs->bUsingBa) {
                        if (SN_LESS(pTxTs->TxAdmittedBARecord.ba_start_seq_ctrl.field.seq_num,
                           (pTxTs->TxCurSeq+1)%4096))
                                pTxTs->bUsingBa = true;
                        else
                                goto FORCED_AGG_SETTING;
                }
                if (ieee->iw_mode == IW_MODE_INFRA) {
                        tcb_desc->bAMPDUEnable = true;
                        tcb_desc->ampdu_factor = pHTInfo->CurrentAMPDUFactor;
                        tcb_desc->ampdu_density = pHTInfo->CurrentMPDUDensity;
                }
        }
FORCED_AGG_SETTING:
        switch (pHTInfo->ForcedAMPDUMode) {
        case HT_AGG_AUTO:
                break;

        case HT_AGG_FORCE_ENABLE:
                tcb_desc->bAMPDUEnable = true;
                tcb_desc->ampdu_density = pHTInfo->ForcedMPDUDensity;
                tcb_desc->ampdu_factor = pHTInfo->ForcedAMPDUFactor;
                break;

        case HT_AGG_FORCE_DISABLE:
                tcb_desc->bAMPDUEnable = false;
                tcb_desc->ampdu_density = 0;
                tcb_desc->ampdu_factor = 0;
                break;
        }
}

static void rtllib_query_ShortPreambleMode(struct rtllib_device *ieee,
                                           struct cb_desc *tcb_desc)
{
        tcb_desc->bUseShortPreamble = false;
        if (tcb_desc->data_rate == 2)
                return;
        else if (ieee->current_network.capability &
                 WLAN_CAPABILITY_SHORT_PREAMBLE)
                tcb_desc->bUseShortPreamble = true;
}

static void rtllib_query_HTCapShortGI(struct rtllib_device *ieee,
                                      struct cb_desc *tcb_desc)
{
        struct rt_hi_throughput *pHTInfo = ieee->pHTInfo;

        tcb_desc->bUseShortGI           = false;

        if (!pHTInfo->bCurrentHTSupport || !pHTInfo->bEnableHT)
                return;

        if (pHTInfo->bForcedShortGI) {
                tcb_desc->bUseShortGI = true;
                return;
        }

        if (pHTInfo->bCurBW40MHz && pHTInfo->bCurShortGI40MHz)
                tcb_desc->bUseShortGI = true;
        else if (!pHTInfo->bCurBW40MHz && pHTInfo->bCurShortGI20MHz)
                tcb_desc->bUseShortGI = true;
}

static void rtllib_query_BandwidthMode(struct rtllib_device *ieee,
                                       struct cb_desc *tcb_desc)
{
        struct rt_hi_throughput *pHTInfo = ieee->pHTInfo;

        tcb_desc->bPacketBW = false;

        if (!pHTInfo->bCurrentHTSupport || !pHTInfo->bEnableHT)
                return;

        if (tcb_desc->bMulticast || tcb_desc->bBroadcast)
                return;

        if ((tcb_desc->data_rate & 0x80) == 0)
                return;
        if (pHTInfo->bCurBW40MHz && pHTInfo->bCurTxBW40MHz &&
            !ieee->bandwidth_auto_switch.bforced_tx20Mhz)
                tcb_desc->bPacketBW = true;
}

static void rtllib_query_protectionmode(struct rtllib_device *ieee,
                                        struct cb_desc *tcb_desc,
                                        struct sk_buff *skb)
{
        struct rt_hi_throughput *pHTInfo;

        tcb_desc->bRTSSTBC                      = false;
        tcb_desc->bRTSUseShortGI                = false;
        tcb_desc->bCTSEnable                    = false;
        tcb_desc->RTSSC                         = 0;
        tcb_desc->bRTSBW                        = false;

        if (tcb_desc->bBroadcast || tcb_desc->bMulticast)
                return;

        if (is_broadcast_ether_addr(skb->data+16))
                return;

        if (ieee->mode < IEEE_N_24G) {
                if (skb->len > ieee->rts) {
                        tcb_desc->bRTSEnable = true;
                        tcb_desc->rts_rate = MGN_24M;
                } else if (ieee->current_network.buseprotection) {
                        tcb_desc->bRTSEnable = true;
                        tcb_desc->bCTSEnable = true;
                        tcb_desc->rts_rate = MGN_24M;
                }
                return;
        }

        pHTInfo = ieee->pHTInfo;

        while (true) {
                if (pHTInfo->IOTAction & HT_IOT_ACT_FORCED_CTS2SELF) {
                        tcb_desc->bCTSEnable    = true;
                        tcb_desc->rts_rate  =   MGN_24M;
                        tcb_desc->bRTSEnable = true;
                        break;
                } else if (pHTInfo->IOTAction & (HT_IOT_ACT_FORCED_RTS |
                           HT_IOT_ACT_PURE_N_MODE)) {
                        tcb_desc->bRTSEnable = true;
                        tcb_desc->rts_rate  =   MGN_24M;
                        break;
                }
                if (ieee->current_network.buseprotection) {
                        tcb_desc->bRTSEnable = true;
                        tcb_desc->bCTSEnable = true;
                        tcb_desc->rts_rate = MGN_24M;
                        break;
                }
                if (pHTInfo->bCurrentHTSupport  && pHTInfo->bEnableHT) {
                        u8 HTOpMode = pHTInfo->CurrentOpMode;

                        if ((pHTInfo->bCurBW40MHz && (HTOpMode == 2 ||
                             HTOpMode == 3)) ||
                             (!pHTInfo->bCurBW40MHz && HTOpMode == 3)) {
                                tcb_desc->rts_rate = MGN_24M;
                                tcb_desc->bRTSEnable = true;
                                break;
                        }
                }
                if (skb->len > ieee->rts) {
                        tcb_desc->rts_rate = MGN_24M;
                        tcb_desc->bRTSEnable = true;
                        break;
                }
                if (tcb_desc->bAMPDUEnable) {
                        tcb_desc->rts_rate = MGN_24M;
                        tcb_desc->bRTSEnable = false;
                        break;
                }
                goto NO_PROTECTION;
        }
        if (ieee->current_network.capability & WLAN_CAPABILITY_SHORT_PREAMBLE)
                tcb_desc->bUseShortPreamble = true;
        if (ieee->iw_mode == IW_MODE_MASTER)
                goto NO_PROTECTION;
        return;
NO_PROTECTION:
        tcb_desc->bRTSEnable    = false;
        tcb_desc->bCTSEnable    = false;
        tcb_desc->rts_rate      = 0;
        tcb_desc->RTSSC         = 0;
        tcb_desc->bRTSBW        = false;
}


static void rtllib_txrate_selectmode(struct rtllib_device *ieee,
                                     struct cb_desc *tcb_desc)
{
        if (ieee->bTxDisableRateFallBack)
                tcb_desc->bTxDisableRateFallBack = true;

        if (ieee->bTxUseDriverAssingedRate)
                tcb_desc->bTxUseDriverAssingedRate = true;
        if (!tcb_desc->bTxDisableRateFallBack ||
            !tcb_desc->bTxUseDriverAssingedRate) {
                if (ieee->iw_mode == IW_MODE_INFRA ||
                    ieee->iw_mode == IW_MODE_ADHOC)
                        tcb_desc->RATRIndex = 0;
        }
}

static u16 rtllib_query_seqnum(struct rtllib_device *ieee, struct sk_buff *skb,
                               u8 *dst)
{
        u16 seqnum = 0;

        if (is_multicast_ether_addr(dst))
                return 0;
        if (IsQoSDataFrame(skb->data)) {
                struct tx_ts_record *pTS = NULL;

                if (!GetTs(ieee, (struct ts_common_info **)(&pTS), dst,
                    skb->priority, TX_DIR, true))
                        return 0;
                seqnum = pTS->TxCurSeq;
                pTS->TxCurSeq = (pTS->TxCurSeq+1)%4096;
                return seqnum;
        }
        return 0;
}

static int wme_downgrade_ac(struct sk_buff *skb)
{
        switch (skb->priority) {
        case 6:
        case 7:
                skb->priority = 5; /* VO -> VI */
                return 0;
        case 4:
        case 5:
                skb->priority = 3; /* VI -> BE */
                return 0;
        case 0:
        case 3:
                skb->priority = 1; /* BE -> BK */
                return 0;
        default:
                return -1;
        }
}

static u8 rtllib_current_rate(struct rtllib_device *ieee)
{
        if (ieee->mode & IEEE_MODE_MASK)
                return ieee->rate;

        if (ieee->HTCurrentOperaRate)
                return ieee->HTCurrentOperaRate;
        else
                return ieee->rate & 0x7F;
}

static int rtllib_xmit_inter(struct sk_buff *skb, struct net_device *dev)
{
        struct rtllib_device *ieee = (struct rtllib_device *)
                                     netdev_priv_rsl(dev);
        struct rtllib_txb *txb = NULL;
        struct rtllib_hdr_3addrqos *frag_hdr;
        int i, bytes_per_frag, nr_frags, bytes_last_frag, frag_size;
        unsigned long flags;
        struct net_device_stats *stats = &ieee->stats;
        int ether_type = 0, encrypt;
        int bytes, fc, qos_ctl = 0, hdr_len;
        struct sk_buff *skb_frag;
        struct rtllib_hdr_3addrqos header = { /* Ensure zero initialized */
                .duration_id = 0,
                .seq_ctl = 0,
                .qos_ctl = 0
        };
        int qos_activated = ieee->current_network.qos_data.active;
        u8 dest[ETH_ALEN];
        u8 src[ETH_ALEN];
        struct lib80211_crypt_data *crypt = NULL;
        struct cb_desc *tcb_desc;
        u8 bIsMulticast = false;
        u8 IsAmsdu = false;
        bool    bdhcp = false;

        spin_lock_irqsave(&ieee->lock, flags);

        /* If there is no driver handler to take the TXB, don't bother
         * creating it...
         */
        if ((!ieee->hard_start_xmit && !(ieee->softmac_features &
           IEEE_SOFTMAC_TX_QUEUE)) ||
           ((!ieee->softmac_data_hard_start_xmit &&
           (ieee->softmac_features & IEEE_SOFTMAC_TX_QUEUE)))) {
                netdev_warn(ieee->dev, "No xmit handler.\n");
                goto success;
        }


        if (likely(ieee->raw_tx == 0)) {
                if (unlikely(skb->len < SNAP_SIZE + sizeof(u16))) {
                        netdev_warn(ieee->dev, "skb too small (%d).\n",
                                    skb->len);
                        goto success;
                }
                /* Save source and destination addresses */
                ether_addr_copy(dest, skb->data);
                ether_addr_copy(src, skb->data + ETH_ALEN);

                memset(skb->cb, 0, sizeof(skb->cb));
                ether_type = ntohs(((struct ethhdr *)skb->data)->h_proto);

                if (ieee->iw_mode == IW_MODE_MONITOR) {
                        txb = rtllib_alloc_txb(1, skb->len, GFP_ATOMIC);
                        if (unlikely(!txb)) {
                                netdev_warn(ieee->dev,
                                            "Could not allocate TXB\n");
                                goto failed;
                        }

                        txb->encrypted = 0;
                        txb->payload_size = cpu_to_le16(skb->len);
                        skb_put_data(txb->fragments[0], skb->data, skb->len);

                        goto success;
                }

                if (skb->len > 282) {
                        if (ether_type == ETH_P_IP) {
                                const struct iphdr *ip = (struct iphdr *)
                                        ((u8 *)skb->data+14);
                                if (ip->protocol == IPPROTO_UDP) {
                                        struct udphdr *udp;

                                        udp = (struct udphdr *)((u8 *)ip +
                                              (ip->ihl << 2));
                                        if (((((u8 *)udp)[1] == 68) &&
                                           (((u8 *)udp)[3] == 67)) ||
                                           ((((u8 *)udp)[1] == 67) &&
                                           (((u8 *)udp)[3] == 68))) {
                                                bdhcp = true;
                                                ieee->LPSDelayCnt = 200;
                                        }
                                }
                        } else if (ether_type == ETH_P_ARP) {
                                netdev_info(ieee->dev,
                                            "=================>DHCP Protocol start tx ARP pkt!!\n");
                                bdhcp = true;
                                ieee->LPSDelayCnt =
                                         ieee->current_network.tim.tim_count;
                        }
                }

                skb->priority = rtllib_classify(skb, IsAmsdu);
                crypt = ieee->crypt_info.crypt[ieee->crypt_info.tx_keyidx];
                encrypt = !(ether_type == ETH_P_PAE && ieee->ieee802_1x) &&
                        ieee->host_encrypt && crypt && crypt->ops;
                if (!encrypt && ieee->ieee802_1x &&
                    ieee->drop_unencrypted && ether_type != ETH_P_PAE) {
                        stats->tx_dropped++;
                        goto success;
                }
                if (crypt && !encrypt && ether_type == ETH_P_PAE) {
                        struct eapol *eap = (struct eapol *)(skb->data +
                                sizeof(struct ethhdr) - SNAP_SIZE -
                                sizeof(u16));
                        netdev_dbg(ieee->dev,
                                   "TX: IEEE 802.11 EAPOL frame: %s\n",
                                   eap_get_type(eap->type));
                }

                /* Advance the SKB to the start of the payload */
                skb_pull(skb, sizeof(struct ethhdr));

                /* Determine total amount of storage required for TXB packets */
                bytes = skb->len + SNAP_SIZE + sizeof(u16);

                if (encrypt)
                        fc = RTLLIB_FTYPE_DATA | RTLLIB_FCTL_WEP;
                else
                        fc = RTLLIB_FTYPE_DATA;

                if (qos_activated)
                        fc |= RTLLIB_STYPE_QOS_DATA;
                else
                        fc |= RTLLIB_STYPE_DATA;

                if (ieee->iw_mode == IW_MODE_INFRA) {
                        fc |= RTLLIB_FCTL_TODS;
                        /* To DS: Addr1 = BSSID, Addr2 = SA,
                         * Addr3 = DA
                         */
                        ether_addr_copy(header.addr1,
                                        ieee->current_network.bssid);
                        ether_addr_copy(header.addr2, src);
                        if (IsAmsdu)
                                ether_addr_copy(header.addr3,
                                                ieee->current_network.bssid);
                        else
                                ether_addr_copy(header.addr3, dest);
                } else if (ieee->iw_mode == IW_MODE_ADHOC) {
                        /* not From/To DS: Addr1 = DA, Addr2 = SA,
                         * Addr3 = BSSID
                         */
                        ether_addr_copy(header.addr1, dest);
                        ether_addr_copy(header.addr2, src);
                        ether_addr_copy(header.addr3,
                                        ieee->current_network.bssid);
                }

                bIsMulticast = is_multicast_ether_addr(header.addr1);

                header.frame_ctl = cpu_to_le16(fc);

                /* Determine fragmentation size based on destination (multicast
                 * and broadcast are not fragmented)
                 */
                if (bIsMulticast) {
                        frag_size = MAX_FRAG_THRESHOLD;
                        qos_ctl |= QOS_CTL_NOTCONTAIN_ACK;
                } else {
                        frag_size = ieee->fts;
                        qos_ctl = 0;
                }

                if (qos_activated) {
                        hdr_len = RTLLIB_3ADDR_LEN + 2;

                        /* in case we are a client verify acm is not set for this ac */
                        while (unlikely(ieee->wmm_acm & (0x01 << skb->priority))) {
                                netdev_info(ieee->dev, "skb->priority = %x\n",
                                                skb->priority);
                                if (wme_downgrade_ac(skb))
                                        break;
                                netdev_info(ieee->dev, "converted skb->priority = %x\n",
                                           skb->priority);
                        }

                        qos_ctl |= skb->priority;
                        header.qos_ctl = cpu_to_le16(qos_ctl & RTLLIB_QOS_TID);

                } else {
                        hdr_len = RTLLIB_3ADDR_LEN;
                }
                /* Determine amount of payload per fragment.  Regardless of if
                 * this stack is providing the full 802.11 header, one will
                 * eventually be affixed to this fragment -- so we must account
                 * for it when determining the amount of payload space.
                 */
                bytes_per_frag = frag_size - hdr_len;
                if (ieee->config &
                   (CFG_RTLLIB_COMPUTE_FCS | CFG_RTLLIB_RESERVE_FCS))
                        bytes_per_frag -= RTLLIB_FCS_LEN;

                /* Each fragment may need to have room for encrypting
                 * pre/postfix
                 */
                if (encrypt) {
                        bytes_per_frag -= crypt->ops->extra_mpdu_prefix_len +
                                crypt->ops->extra_mpdu_postfix_len +
                                crypt->ops->extra_msdu_prefix_len +
                                crypt->ops->extra_msdu_postfix_len;
                }
                /* Number of fragments is the total bytes_per_frag /
                 * payload_per_fragment
                 */
                nr_frags = bytes / bytes_per_frag;
                bytes_last_frag = bytes % bytes_per_frag;
                if (bytes_last_frag)
                        nr_frags++;
                else
                        bytes_last_frag = bytes_per_frag;

                /* When we allocate the TXB we allocate enough space for the
                 * reserve and full fragment bytes (bytes_per_frag doesn't
                 * include prefix, postfix, header, FCS, etc.)
                 */
                txb = rtllib_alloc_txb(nr_frags, frag_size +
                                       ieee->tx_headroom, GFP_ATOMIC);
                if (unlikely(!txb)) {
                        netdev_warn(ieee->dev, "Could not allocate TXB\n");
                        goto failed;
                }
                txb->encrypted = encrypt;
                txb->payload_size = cpu_to_le16(bytes);

                if (qos_activated)
                        txb->queue_index = UP2AC(skb->priority);
                else
                        txb->queue_index = WME_AC_BE;

                for (i = 0; i < nr_frags; i++) {
                        skb_frag = txb->fragments[i];
                        tcb_desc = (struct cb_desc *)(skb_frag->cb +
                                    MAX_DEV_ADDR_SIZE);
                        if (qos_activated) {
                                skb_frag->priority = skb->priority;
                                tcb_desc->queue_index =  UP2AC(skb->priority);
                        } else {
                                skb_frag->priority = WME_AC_BE;
                                tcb_desc->queue_index = WME_AC_BE;
                        }
                        skb_reserve(skb_frag, ieee->tx_headroom);

                        if (encrypt) {
                                if (ieee->hwsec_active)
                                        tcb_desc->bHwSec = 1;
                                else
                                        tcb_desc->bHwSec = 0;
                                skb_reserve(skb_frag,
                                            crypt->ops->extra_mpdu_prefix_len +
                                            crypt->ops->extra_msdu_prefix_len);
                        } else {
                                tcb_desc->bHwSec = 0;
                        }
                        frag_hdr = skb_put_data(skb_frag, &header, hdr_len);

                        /* If this is not the last fragment, then add the
                         * MOREFRAGS bit to the frame control
                         */
                        if (i != nr_frags - 1) {
                                frag_hdr->frame_ctl = cpu_to_le16(
                                        fc | RTLLIB_FCTL_MOREFRAGS);
                                bytes = bytes_per_frag;

                        } else {
                                /* The last fragment has the remaining length */
                                bytes = bytes_last_frag;
                        }
                        if ((qos_activated) && (!bIsMulticast)) {
                                frag_hdr->seq_ctl =
                                         cpu_to_le16(rtllib_query_seqnum(ieee, skb_frag,
                                                             header.addr1));
                                frag_hdr->seq_ctl =
                                         cpu_to_le16(le16_to_cpu(frag_hdr->seq_ctl)<<4 | i);
                        } else {
                                frag_hdr->seq_ctl =
                                         cpu_to_le16(ieee->seq_ctrl[0]<<4 | i);
                        }
                        /* Put a SNAP header on the first fragment */
                        if (i == 0) {
                                rtllib_put_snap(
                                        skb_put(skb_frag, SNAP_SIZE +
                                        sizeof(u16)), ether_type);
                                bytes -= SNAP_SIZE + sizeof(u16);
                        }

                        skb_put_data(skb_frag, skb->data, bytes);

                        /* Advance the SKB... */
                        skb_pull(skb, bytes);

                        /* Encryption routine will move the header forward in
                         * order to insert the IV between the header and the
                         * payload
                         */
                        if (encrypt)
                                rtllib_encrypt_fragment(ieee, skb_frag,
                                                        hdr_len);
                        if (ieee->config &
                           (CFG_RTLLIB_COMPUTE_FCS | CFG_RTLLIB_RESERVE_FCS))
                                skb_put(skb_frag, 4);
                }

                if ((qos_activated) && (!bIsMulticast)) {
                        if (ieee->seq_ctrl[UP2AC(skb->priority) + 1] == 0xFFF)
                                ieee->seq_ctrl[UP2AC(skb->priority) + 1] = 0;
                        else
                                ieee->seq_ctrl[UP2AC(skb->priority) + 1]++;
                } else {
                        if (ieee->seq_ctrl[0] == 0xFFF)
                                ieee->seq_ctrl[0] = 0;
                        else
                                ieee->seq_ctrl[0]++;
                }
        } else {
                if (unlikely(skb->len < sizeof(struct rtllib_hdr_3addr))) {
                        netdev_warn(ieee->dev, "skb too small (%d).\n",
                                    skb->len);
                        goto success;
                }

                txb = rtllib_alloc_txb(1, skb->len, GFP_ATOMIC);
                if (!txb) {
                        netdev_warn(ieee->dev, "Could not allocate TXB\n");
                        goto failed;
                }

                txb->encrypted = 0;
                txb->payload_size = cpu_to_le16(skb->len);
                skb_put_data(txb->fragments[0], skb->data, skb->len);
        }

 success:
        if (txb) {
                tcb_desc = (struct cb_desc *)
                                (txb->fragments[0]->cb + MAX_DEV_ADDR_SIZE);
                tcb_desc->bTxEnableFwCalcDur = 1;
                tcb_desc->priority = skb->priority;

                if (ether_type == ETH_P_PAE) {
                        if (ieee->pHTInfo->IOTAction &
                            HT_IOT_ACT_WA_IOT_Broadcom) {
                                tcb_desc->data_rate =
                                         MgntQuery_TxRateExcludeCCKRates(ieee);
                                tcb_desc->bTxDisableRateFallBack = false;
                        } else {
                                tcb_desc->data_rate = ieee->basic_rate;
                                tcb_desc->bTxDisableRateFallBack = 1;
                        }


                        tcb_desc->RATRIndex = 7;
                        tcb_desc->bTxUseDriverAssingedRate = 1;
                } else {
                        if (is_multicast_ether_addr(header.addr1))
                                tcb_desc->bMulticast = 1;
                        if (is_broadcast_ether_addr(header.addr1))
                                tcb_desc->bBroadcast = 1;
                        rtllib_txrate_selectmode(ieee, tcb_desc);
                        if (tcb_desc->bMulticast ||  tcb_desc->bBroadcast)
                                tcb_desc->data_rate = ieee->basic_rate;
                        else
                                tcb_desc->data_rate = rtllib_current_rate(ieee);

                        if (bdhcp) {
                                if (ieee->pHTInfo->IOTAction &
                                    HT_IOT_ACT_WA_IOT_Broadcom) {
                                        tcb_desc->data_rate =
                                           MgntQuery_TxRateExcludeCCKRates(ieee);
                                        tcb_desc->bTxDisableRateFallBack = false;
                                } else {
                                        tcb_desc->data_rate = MGN_1M;
                                        tcb_desc->bTxDisableRateFallBack = 1;
                                }


                                tcb_desc->RATRIndex = 7;
                                tcb_desc->bTxUseDriverAssingedRate = 1;
                                tcb_desc->bdhcp = 1;
                        }

                        rtllib_query_ShortPreambleMode(ieee, tcb_desc);
                        rtllib_tx_query_agg_cap(ieee, txb->fragments[0],
                                                tcb_desc);
                        rtllib_query_HTCapShortGI(ieee, tcb_desc);
                        rtllib_query_BandwidthMode(ieee, tcb_desc);
                        rtllib_query_protectionmode(ieee, tcb_desc,
                                                    txb->fragments[0]);
                }
        }
        spin_unlock_irqrestore(&ieee->lock, flags);
        dev_kfree_skb_any(skb);
        if (txb) {
                if (ieee->softmac_features & IEEE_SOFTMAC_TX_QUEUE) {
                        dev->stats.tx_packets++;
                        dev->stats.tx_bytes += le16_to_cpu(txb->payload_size);
                        rtllib_softmac_xmit(txb, ieee);
                } else {
                        if ((*ieee->hard_start_xmit)(txb, dev) == 0) {
                                stats->tx_packets++;
                                stats->tx_bytes += le16_to_cpu(txb->payload_size);
                                return 0;
                        }
                        rtllib_txb_free(txb);
                }
        }

        return 0;

 failed:
        spin_unlock_irqrestore(&ieee->lock, flags);
        netif_stop_queue(dev);
        stats->tx_errors++;
        return 1;

}

int rtllib_xmit(struct sk_buff *skb, struct net_device *dev)
{
        memset(skb->cb, 0, sizeof(skb->cb));
        return rtllib_xmit_inter(skb, dev);
}
EXPORT_SYMBOL(rtllib_xmit);