/*
 * dvb_net.c
 *
 * Copyright (C) 2001 Convergence integrated media GmbH
 *                    Ralph Metzler <ralph@convergence.de>
 * Copyright (C) 2002 Ralph Metzler <rjkm@metzlerbros.de>
 *
 * ULE Decapsulation code:
 * Copyright (C) 2003, 2004 gcs - Global Communication & Services GmbH.
 *                      and Department of Scientific Computing
 *                          Paris Lodron University of Salzburg.
 *                          Hilmar Linder <hlinder@cosy.sbg.ac.at>
 *                      and Wolfram Stering <wstering@cosy.sbg.ac.at>
 *
 * ULE Decaps according to RFC 4326.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 * Or, point your browser to http://www.gnu.org/copyleft/gpl.html
 */

/*
 * ULE ChangeLog:
 * Feb 2004: hl/ws v1: Implementing draft-fair-ipdvb-ule-01.txt
 *
 * Dec 2004: hl/ws v2: Implementing draft-ietf-ipdvb-ule-03.txt:
 *                       ULE Extension header handling.
 *                     Bugreports by Moritz Vieth and Hanno Tersteegen,
 *                       Fraunhofer Institute for Open Communication Systems
 *                       Competence Center for Advanced Satellite Communications.
 *                     Bugfixes and robustness improvements.
 *                     Filtering on dest MAC addresses, if present (D-Bit = 0)
 *                     ULE_DEBUG compile-time option.
 * Apr 2006: cp v3:    Bugfixes and compliency with RFC 4326 (ULE) by
 *                       Christian Praehauser <cpraehaus@cosy.sbg.ac.at>,
 *                       Paris Lodron University of Salzburg.
 */

/*
 * FIXME / TODO (dvb_net.c):
 *
 * Unloading does not work for 2.6.9 kernels: a refcount doesn't go to zero.
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/dvb/net.h>
#include <linux/uio.h>
#include <asm/uaccess.h>
#include <linux/crc32.h>
#include <linux/mutex.h>
#include <linux/sched.h>

#include "dvb_demux.h"
#include "dvb_net.h"

static inline __u32 iov_crc32( __u32 c, struct kvec *iov, unsigned int cnt )
{
        unsigned int j;
        for (j = 0; j < cnt; j++)
                c = crc32_be( c, iov[j].iov_base, iov[j].iov_len );
        return c;
}


#define DVB_NET_MULTICAST_MAX 10

#undef ULE_DEBUG

#ifdef ULE_DEBUG

static void hexdump(const unsigned char *buf, unsigned short len)
{
        print_hex_dump_debug("", DUMP_PREFIX_OFFSET, 16, 1, buf, len, true);
}

#endif

struct dvb_net_priv {
        int in_use;
        u16 pid;
        struct net_device *net;
        struct dvb_net *host;
        struct dmx_demux *demux;
        struct dmx_section_feed *secfeed;
        struct dmx_section_filter *secfilter;
        struct dmx_ts_feed *tsfeed;
        int multi_num;
        struct dmx_section_filter *multi_secfilter[DVB_NET_MULTICAST_MAX];
        unsigned char multi_macs[DVB_NET_MULTICAST_MAX][6];
        int rx_mode;
#define RX_MODE_UNI 0
#define RX_MODE_MULTI 1
#define RX_MODE_ALL_MULTI 2
#define RX_MODE_PROMISC 3
        struct work_struct set_multicast_list_wq;
        struct work_struct restart_net_feed_wq;
        unsigned char feedtype;                 /* Either FEED_TYPE_ or FEED_TYPE_ULE */
        int need_pusi;                          /* Set to 1, if synchronization on PUSI required. */
        unsigned char tscc;                     /* TS continuity counter after sync on PUSI. */
        struct sk_buff *ule_skb;                /* ULE SNDU decodes into this buffer. */
        unsigned char *ule_next_hdr;            /* Pointer into skb to next ULE extension header. */
        unsigned short ule_sndu_len;            /* ULE SNDU length in bytes, w/o D-Bit. */
        unsigned short ule_sndu_type;           /* ULE SNDU type field, complete. */
        unsigned char ule_sndu_type_1;          /* ULE SNDU type field, if split across 2 TS cells. */
        unsigned char ule_dbit;                 /* Whether the DestMAC address present
                                                 * or not (bit is set). */
        unsigned char ule_bridged;              /* Whether the ULE_BRIDGED extension header was found. */
        int ule_sndu_remain;                    /* Nr. of bytes still required for current ULE SNDU. */
        unsigned long ts_count;                 /* Current ts cell counter. */
        struct mutex mutex;
};


/**
 *      Determine the packet's protocol ID. The rule here is that we
 *      assume 802.3 if the type field is short enough to be a length.
 *      This is normal practice and works for any 'now in use' protocol.
 *
 *  stolen from eth.c out of the linux kernel, hacked for dvb-device
 *  by Michael Holzt <kju@debian.org>
 */
static __be16 dvb_net_eth_type_trans(struct sk_buff *skb,
                                      struct net_device *dev)
{
        struct ethhdr *eth;
        unsigned char *rawp;

        skb_reset_mac_header(skb);
        skb_pull(skb,dev->hard_header_len);
        eth = eth_hdr(skb);

        if (*eth->h_dest & 1) {
                if(ether_addr_equal(eth->h_dest,dev->broadcast))
                        skb->pkt_type=PACKET_BROADCAST;
                else
                        skb->pkt_type=PACKET_MULTICAST;
        }

        if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN)
                return eth->h_proto;

        rawp = skb->data;

        /**
         *      This is a magic hack to spot IPX packets. Older Novell breaks
         *      the protocol design and runs IPX over 802.3 without an 802.2 LLC
         *      layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
         *      won't work for fault tolerant netware but does for the rest.
         */
        if (*(unsigned short *)rawp == 0xFFFF)
                return htons(ETH_P_802_3);

        /**
         *      Real 802.2 LLC
         */
        return htons(ETH_P_802_2);
}

#define TS_SZ   188
#define TS_SYNC 0x47
#define TS_TEI  0x80
#define TS_SC   0xC0
#define TS_PUSI 0x40
#define TS_AF_A 0x20
#define TS_AF_D 0x10

/* ULE Extension Header handlers. */

#define ULE_TEST        0
#define ULE_BRIDGED     1

#define ULE_OPTEXTHDR_PADDING 0

static int ule_test_sndu( struct dvb_net_priv *p )
{
        return -1;
}

static int ule_bridged_sndu( struct dvb_net_priv *p )
{
        struct ethhdr *hdr = (struct ethhdr*) p->ule_next_hdr;
        if(ntohs(hdr->h_proto) < ETH_P_802_3_MIN) {
                int framelen = p->ule_sndu_len - ((p->ule_next_hdr+sizeof(struct ethhdr)) - p->ule_skb->data);
                /* A frame Type < ETH_P_802_3_MIN for a bridged frame, introduces a LLC Length field. */
                if(framelen != ntohs(hdr->h_proto)) {
                        return -1;
                }
        }
        /* Note:
         * From RFC4326:
         *  "A bridged SNDU is a Mandatory Extension Header of Type 1.
         *   It must be the final (or only) extension header specified in the header chain of a SNDU."
         * The 'ule_bridged' flag will cause the extension header processing loop to terminate.
         */
        p->ule_bridged = 1;
        return 0;
}

static int ule_exthdr_padding(struct dvb_net_priv *p)
{
        return 0;
}

/** Handle ULE extension headers.
 *  Function is called after a successful CRC32 verification of an ULE SNDU to complete its decoding.
 *  Returns: >= 0: nr. of bytes consumed by next extension header
 *           -1:   Mandatory extension header that is not recognized or TEST SNDU; discard.
 */
static int handle_one_ule_extension( struct dvb_net_priv *p )
{
        /* Table of mandatory extension header handlers.  The header type is the index. */
        static int (*ule_mandatory_ext_handlers[255])( struct dvb_net_priv *p ) =
                { [0] = ule_test_sndu, [1] = ule_bridged_sndu, [2] = NULL,  };

        /* Table of optional extension header handlers.  The header type is the index. */
        static int (*ule_optional_ext_handlers[255])( struct dvb_net_priv *p ) =
                { [0] = ule_exthdr_padding, [1] = NULL, };

        int ext_len = 0;
        unsigned char hlen = (p->ule_sndu_type & 0x0700) >> 8;
        unsigned char htype = p->ule_sndu_type & 0x00FF;

        /* Discriminate mandatory and optional extension headers. */
        if (hlen == 0) {
                /* Mandatory extension header */
                if (ule_mandatory_ext_handlers[htype]) {
                        ext_len = ule_mandatory_ext_handlers[htype]( p );
                        if(ext_len >= 0) {
                                p->ule_next_hdr += ext_len;
                                if (!p->ule_bridged) {
                                        p->ule_sndu_type = ntohs(*(__be16 *)p->ule_next_hdr);
                                        p->ule_next_hdr += 2;
                                } else {
                                        p->ule_sndu_type = ntohs(*(__be16 *)(p->ule_next_hdr + ((p->ule_dbit ? 2 : 3) * ETH_ALEN)));
                                        /* This assures the extension handling loop will terminate. */
                                }
                        }
                        // else: extension handler failed or SNDU should be discarded
                } else
                        ext_len = -1;   /* SNDU has to be discarded. */
        } else {
                /* Optional extension header.  Calculate the length. */
                ext_len = hlen << 1;
                /* Process the optional extension header according to its type. */
                if (ule_optional_ext_handlers[htype])
                        (void)ule_optional_ext_handlers[htype]( p );
                p->ule_next_hdr += ext_len;
                p->ule_sndu_type = ntohs( *(__be16 *)(p->ule_next_hdr-2) );
                /*
                 * note: the length of the next header type is included in the
                 * length of THIS optional extension header
                 */
        }

        return ext_len;
}

static int handle_ule_extensions( struct dvb_net_priv *p )
{
        int total_ext_len = 0, l;

        p->ule_next_hdr = p->ule_skb->data;
        do {
                l = handle_one_ule_extension( p );
                if (l < 0)
                        return l;       /* Stop extension header processing and discard SNDU. */
                total_ext_len += l;
#ifdef ULE_DEBUG
                pr_debug("ule_next_hdr=%p, ule_sndu_type=%i, l=%i, total_ext_len=%i\n",
                         p->ule_next_hdr, (int)p->ule_sndu_type,
                         l, total_ext_len);
#endif

        } while (p->ule_sndu_type < ETH_P_802_3_MIN);

        return total_ext_len;
}


/** Prepare for a new ULE SNDU: reset the decoder state. */
static inline void reset_ule( struct dvb_net_priv *p )
{
        p->ule_skb = NULL;
        p->ule_next_hdr = NULL;
        p->ule_sndu_len = 0;
        p->ule_sndu_type = 0;
        p->ule_sndu_type_1 = 0;
        p->ule_sndu_remain = 0;
        p->ule_dbit = 0xFF;
        p->ule_bridged = 0;
}

/**
 * Decode ULE SNDUs according to draft-ietf-ipdvb-ule-03.txt from a sequence of
 * TS cells of a single PID.
 */
static void dvb_net_ule( struct net_device *dev, const u8 *buf, size_t buf_len )
{
        struct dvb_net_priv *priv = netdev_priv(dev);
        unsigned long skipped = 0L;
        const u8 *ts, *ts_end, *from_where = NULL;
        u8 ts_remain = 0, how_much = 0, new_ts = 1;
        struct ethhdr *ethh = NULL;
        bool error = false;

#ifdef ULE_DEBUG
        /* The code inside ULE_DEBUG keeps a history of the last 100 TS cells processed. */
        static unsigned char ule_hist[100*TS_SZ];
        static unsigned char *ule_where = ule_hist, ule_dump;
#endif

        /* For all TS cells in current buffer.
         * Appearently, we are called for every single TS cell.
         */
        for (ts = buf, ts_end = buf + buf_len; ts < ts_end; /* no default incr. */ ) {

                if (new_ts) {
                        /* We are about to process a new TS cell. */

#ifdef ULE_DEBUG
                        if (ule_where >= &ule_hist[100*TS_SZ]) ule_where = ule_hist;
                        memcpy( ule_where, ts, TS_SZ );
                        if (ule_dump) {
                                hexdump( ule_where, TS_SZ );
                                ule_dump = 0;
                        }
                        ule_where += TS_SZ;
#endif

                        /* Check TS error conditions: sync_byte, transport_error_indicator, scrambling_control . */
                        if ((ts[0] != TS_SYNC) || (ts[1] & TS_TEI) || ((ts[3] & TS_SC) != 0)) {
                                printk(KERN_WARNING "%lu: Invalid TS cell: SYNC %#x, TEI %u, SC %#x.\n",
                                       priv->ts_count, ts[0],
                                       (ts[1] & TS_TEI) >> 7,
                                       (ts[3] & TS_SC) >> 6);

                                /* Drop partly decoded SNDU, reset state, resync on PUSI. */
                                if (priv->ule_skb) {
                                        dev_kfree_skb( priv->ule_skb );
                                        /* Prepare for next SNDU. */
                                        dev->stats.rx_errors++;
                                        dev->stats.rx_frame_errors++;
                                }
                                reset_ule(priv);
                                priv->need_pusi = 1;

                                /* Continue with next TS cell. */
                                ts += TS_SZ;
                                priv->ts_count++;
                                continue;
                        }

                        ts_remain = 184;
                        from_where = ts + 4;
                }
                /* Synchronize on PUSI, if required. */
                if (priv->need_pusi) {
                        if (ts[1] & TS_PUSI) {
                                /* Find beginning of first ULE SNDU in current TS cell. */
                                /* Synchronize continuity counter. */
                                priv->tscc = ts[3] & 0x0F;
                                /* There is a pointer field here. */
                                if (ts[4] > ts_remain) {
                                        printk(KERN_ERR "%lu: Invalid ULE packet "
                                               "(pointer field %d)\n", priv->ts_count, ts[4]);
                                        ts += TS_SZ;
                                        priv->ts_count++;
                                        continue;
                                }
                                /* Skip to destination of pointer field. */
                                from_where = &ts[5] + ts[4];
                                ts_remain -= 1 + ts[4];
                                skipped = 0;
                        } else {
                                skipped++;
                                ts += TS_SZ;
                                priv->ts_count++;
                                continue;
                        }
                }

                if (new_ts) {
                        /* Check continuity counter. */
                        if ((ts[3] & 0x0F) == priv->tscc)
                                priv->tscc = (priv->tscc + 1) & 0x0F;
                        else {
                                /* TS discontinuity handling: */
                                printk(KERN_WARNING "%lu: TS discontinuity: got %#x, "
                                       "expected %#x.\n", priv->ts_count, ts[3] & 0x0F, priv->tscc);
                                /* Drop partly decoded SNDU, reset state, resync on PUSI. */
                                if (priv->ule_skb) {
                                        dev_kfree_skb( priv->ule_skb );
                                        /* Prepare for next SNDU. */
                                        // reset_ule(priv);  moved to below.
                                        dev->stats.rx_errors++;
                                        dev->stats.rx_frame_errors++;
                                }
                                reset_ule(priv);
                                /* skip to next PUSI. */
                                priv->need_pusi = 1;
                                continue;
                        }
                        /* If we still have an incomplete payload, but PUSI is
                         * set; some TS cells are missing.
                         * This is only possible here, if we missed exactly 16 TS
                         * cells (continuity counter wrap). */
                        if (ts[1] & TS_PUSI) {
                                if (! priv->need_pusi) {
                                        if (!(*from_where < (ts_remain-1)) || *from_where != priv->ule_sndu_remain) {
                                                /* Pointer field is invalid.  Drop this TS cell and any started ULE SNDU. */
                                                printk(KERN_WARNING "%lu: Invalid pointer "
                                                       "field: %u.\n", priv->ts_count, *from_where);

                                                /* Drop partly decoded SNDU, reset state, resync on PUSI. */
                                                if (priv->ule_skb) {
                                                        error = true;
                                                        dev_kfree_skb(priv->ule_skb);
                                                }

                                                if (error || priv->ule_sndu_remain) {
                                                        dev->stats.rx_errors++;
                                                        dev->stats.rx_frame_errors++;
                                                        error = false;
                                                }

                                                reset_ule(priv);
                                                priv->need_pusi = 1;
                                                continue;
                                        }
                                        /* Skip pointer field (we're processing a
                                         * packed payload). */
                                        from_where += 1;
                                        ts_remain -= 1;
                                } else
                                        priv->need_pusi = 0;

                                if (priv->ule_sndu_remain > 183) {
                                        /* Current SNDU lacks more data than there could be available in the
                                         * current TS cell. */
                                        dev->stats.rx_errors++;
                                        dev->stats.rx_length_errors++;
                                        printk(KERN_WARNING "%lu: Expected %d more SNDU bytes, but "
                                               "got PUSI (pf %d, ts_remain %d).  Flushing incomplete payload.\n",
                                               priv->ts_count, priv->ule_sndu_remain, ts[4], ts_remain);
                                        dev_kfree_skb(priv->ule_skb);
                                        /* Prepare for next SNDU. */
                                        reset_ule(priv);
                                        /* Resync: go to where pointer field points to: start of next ULE SNDU. */
                                        from_where += ts[4];
                                        ts_remain -= ts[4];
                                }
                        }
                }

                /* Check if new payload needs to be started. */
                if (priv->ule_skb == NULL) {
                        /* Start a new payload with skb.
                         * Find ULE header.  It is only guaranteed that the
                         * length field (2 bytes) is contained in the current
                         * TS.
                         * Check ts_remain has to be >= 2 here. */
                        if (ts_remain < 2) {
                                printk(KERN_WARNING "Invalid payload packing: only %d "
                                       "bytes left in TS.  Resyncing.\n", ts_remain);
                                priv->ule_sndu_len = 0;
                                priv->need_pusi = 1;
                                ts += TS_SZ;
                                continue;
                        }

                        if (! priv->ule_sndu_len) {
                                /* Got at least two bytes, thus extrace the SNDU length. */
                                priv->ule_sndu_len = from_where[0] << 8 | from_where[1];
                                if (priv->ule_sndu_len & 0x8000) {
                                        /* D-Bit is set: no dest mac present. */
                                        priv->ule_sndu_len &= 0x7FFF;
                                        priv->ule_dbit = 1;
                                } else
                                        priv->ule_dbit = 0;

                                if (priv->ule_sndu_len < 5) {
                                        printk(KERN_WARNING "%lu: Invalid ULE SNDU length %u. "
                                               "Resyncing.\n", priv->ts_count, priv->ule_sndu_len);
                                        dev->stats.rx_errors++;
                                        dev->stats.rx_length_errors++;
                                        priv->ule_sndu_len = 0;
                                        priv->need_pusi = 1;
                                        new_ts = 1;
                                        ts += TS_SZ;
                                        priv->ts_count++;
                                        continue;
                                }
                                ts_remain -= 2; /* consume the 2 bytes SNDU length. */
                                from_where += 2;
                        }

                        priv->ule_sndu_remain = priv->ule_sndu_len + 2;
                        /*
                         * State of current TS:
                         *   ts_remain (remaining bytes in the current TS cell)
                         *   0  ule_type is not available now, we need the next TS cell
                         *   1  the first byte of the ule_type is present
                         * >=2  full ULE header present, maybe some payload data as well.
                         */
                        switch (ts_remain) {
                                case 1:
                                        priv->ule_sndu_remain--;
                                        priv->ule_sndu_type = from_where[0] << 8;
                                        priv->ule_sndu_type_1 = 1; /* first byte of ule_type is set. */
                                        ts_remain -= 1; from_where += 1;
                                        /* Continue w/ next TS. */
                                case 0:
                                        new_ts = 1;
                                        ts += TS_SZ;
                                        priv->ts_count++;
                                        continue;

                                default: /* complete ULE header is present in current TS. */
                                        /* Extract ULE type field. */
                                        if (priv->ule_sndu_type_1) {
                                                priv->ule_sndu_type_1 = 0;
                                                priv->ule_sndu_type |= from_where[0];
                                                from_where += 1; /* points to payload start. */
                                                ts_remain -= 1;
                                        } else {
                                                /* Complete type is present in new TS. */
                                                priv->ule_sndu_type = from_where[0] << 8 | from_where[1];
                                                from_where += 2; /* points to payload start. */
                                                ts_remain -= 2;
                                        }
                                        break;
                        }

                        /* Allocate the skb (decoder target buffer) with the correct size, as follows:
                         * prepare for the largest case: bridged SNDU with MAC address (dbit = 0). */
                        priv->ule_skb = dev_alloc_skb( priv->ule_sndu_len + ETH_HLEN + ETH_ALEN );
                        if (priv->ule_skb == NULL) {
                                printk(KERN_NOTICE "%s: Memory squeeze, dropping packet.\n",
                                       dev->name);
                                dev->stats.rx_dropped++;
                                return;
                        }

                        /* This includes the CRC32 _and_ dest mac, if !dbit. */
                        priv->ule_sndu_remain = priv->ule_sndu_len;
                        priv->ule_skb->dev = dev;
                        /* Leave space for Ethernet or bridged SNDU header (eth hdr plus one MAC addr). */
                        skb_reserve( priv->ule_skb, ETH_HLEN + ETH_ALEN );
                }

                /* Copy data into our current skb. */
                how_much = min(priv->ule_sndu_remain, (int)ts_remain);
                memcpy(skb_put(priv->ule_skb, how_much), from_where, how_much);
                priv->ule_sndu_remain -= how_much;
                ts_remain -= how_much;
                from_where += how_much;

                /* Check for complete payload. */
                if (priv->ule_sndu_remain <= 0) {
                        /* Check CRC32, we've got it in our skb already. */
                        __be16 ulen = htons(priv->ule_sndu_len);
                        __be16 utype = htons(priv->ule_sndu_type);
                        const u8 *tail;
                        struct kvec iov[3] = {
                                { &ulen, sizeof ulen },
                                { &utype, sizeof utype },
                                { priv->ule_skb->data, priv->ule_skb->len - 4 }
                        };
                        u32 ule_crc = ~0L, expected_crc;
                        if (priv->ule_dbit) {
                                /* Set D-bit for CRC32 verification,
                                 * if it was set originally. */
                                ulen |= htons(0x8000);
                        }

                        ule_crc = iov_crc32(ule_crc, iov, 3);
                        tail = skb_tail_pointer(priv->ule_skb);
                        expected_crc = *(tail - 4) << 24 |
                                       *(tail - 3) << 16 |
                                       *(tail - 2) << 8 |
                                       *(tail - 1);
                        if (ule_crc != expected_crc) {
                                printk(KERN_WARNING "%lu: CRC32 check FAILED: %08x / %08x, SNDU len %d type %#x, ts_remain %d, next 2: %x.\n",
                                       priv->ts_count, ule_crc, expected_crc, priv->ule_sndu_len, priv->ule_sndu_type, ts_remain, ts_remain > 2 ? *(unsigned short *)from_where : 0);

#ifdef ULE_DEBUG
                                hexdump( iov[0].iov_base, iov[0].iov_len );
                                hexdump( iov[1].iov_base, iov[1].iov_len );
                                hexdump( iov[2].iov_base, iov[2].iov_len );

                                if (ule_where == ule_hist) {
                                        hexdump( &ule_hist[98*TS_SZ], TS_SZ );
                                        hexdump( &ule_hist[99*TS_SZ], TS_SZ );
                                } else if (ule_where == &ule_hist[TS_SZ]) {
                                        hexdump( &ule_hist[99*TS_SZ], TS_SZ );
                                        hexdump( ule_hist, TS_SZ );
                                } else {
                                        hexdump( ule_where - TS_SZ - TS_SZ, TS_SZ );
                                        hexdump( ule_where - TS_SZ, TS_SZ );
                                }
                                ule_dump = 1;
#endif

                                dev->stats.rx_errors++;
                                dev->stats.rx_crc_errors++;
                                dev_kfree_skb(priv->ule_skb);
                        } else {
                                /* CRC32 verified OK. */
                                u8 dest_addr[ETH_ALEN];
                                static const u8 bc_addr[ETH_ALEN] =
                                        { [ 0 ... ETH_ALEN-1] = 0xff };

                                /* CRC32 was OK. Remove it from skb. */
                                priv->ule_skb->tail -= 4;
                                priv->ule_skb->len -= 4;

                                if (!priv->ule_dbit) {
                                        /*
                                         * The destination MAC address is the
                                         * next data in the skb.  It comes
                                         * before any extension headers.
                                         *
                                         * Check if the payload of this SNDU
                                         * should be passed up the stack.
                                         */
                                        register int drop = 0;
                                        if (priv->rx_mode != RX_MODE_PROMISC) {
                                                if (priv->ule_skb->data[0] & 0x01) {
                                                        /* multicast or broadcast */
                                                        if (!ether_addr_equal(priv->ule_skb->data, bc_addr)) {
                                                                /* multicast */
                                                                if (priv->rx_mode == RX_MODE_MULTI) {
                                                                        int i;
                                                                        for(i = 0; i < priv->multi_num &&
                                                                            !ether_addr_equal(priv->ule_skb->data,
                                                                                              priv->multi_macs[i]); i++)
                                                                                ;
                                                                        if (i == priv->multi_num)
                                                                                drop = 1;
                                                                } else if (priv->rx_mode != RX_MODE_ALL_MULTI)
                                                                        drop = 1; /* no broadcast; */
                                                                /* else: all multicast mode: accept all multicast packets */
                                                        }
                                                        /* else: broadcast */
                                                }
                                                else if (!ether_addr_equal(priv->ule_skb->data, dev->dev_addr))
                                                        drop = 1;
                                                /* else: destination address matches the MAC address of our receiver device */
                                        }
                                        /* else: promiscuous mode; pass everything up the stack */

                                        if (drop) {
#ifdef ULE_DEBUG
                                                netdev_dbg(dev, "Dropping SNDU: MAC destination address does not match: dest addr: %pM, dev addr: %pM\n",
                                                           priv->ule_skb->data, dev->dev_addr);
#endif
                                                dev_kfree_skb(priv->ule_skb);
                                                goto sndu_done;
                                        }
                                        else
                                        {
                                                skb_copy_from_linear_data(priv->ule_skb,
                                                              dest_addr,
                                                              ETH_ALEN);
                                                skb_pull(priv->ule_skb, ETH_ALEN);
                                        }
                                }

                                /* Handle ULE Extension Headers. */
                                if (priv->ule_sndu_type < ETH_P_802_3_MIN) {
                                        /* There is an extension header.  Handle it accordingly. */
                                        int l = handle_ule_extensions(priv);
                                        if (l < 0) {
                                                /* Mandatory extension header unknown or TEST SNDU.  Drop it. */
                                                // printk( KERN_WARNING "Dropping SNDU, extension headers.\n" );
                                                dev_kfree_skb(priv->ule_skb);
                                                goto sndu_done;
                                        }
                                        skb_pull(priv->ule_skb, l);
                                }

                                /*
                                 * Construct/assure correct ethernet header.
                                 * Note: in bridged mode (priv->ule_bridged !=
                                 * 0) we already have the (original) ethernet
                                 * header at the start of the payload (after
                                 * optional dest. address and any extension
                                 * headers).
                                 */

                                if (!priv->ule_bridged) {
                                        skb_push(priv->ule_skb, ETH_HLEN);
                                        ethh = (struct ethhdr *)priv->ule_skb->data;
                                        if (!priv->ule_dbit) {
                                                 /* dest_addr buffer is only valid if priv->ule_dbit == 0 */
                                                memcpy(ethh->h_dest, dest_addr, ETH_ALEN);
                                                eth_zero_addr(ethh->h_source);
                                        }
                                        else /* zeroize source and dest */
                                                memset( ethh, 0, ETH_ALEN*2 );

                                        ethh->h_proto = htons(priv->ule_sndu_type);
                                }
                                /* else:  skb is in correct state; nothing to do. */
                                priv->ule_bridged = 0;

                                /* Stuff into kernel's protocol stack. */
                                priv->ule_skb->protocol = dvb_net_eth_type_trans(priv->ule_skb, dev);
                                /* If D-bit is set (i.e. destination MAC address not present),
                                 * receive the packet anyhow. */
                                /* if (priv->ule_dbit && skb->pkt_type == PACKET_OTHERHOST)
                                        priv->ule_skb->pkt_type = PACKET_HOST; */
                                dev->stats.rx_packets++;
                                dev->stats.rx_bytes += priv->ule_skb->len;
                                netif_rx(priv->ule_skb);
                        }
                        sndu_done:
                        /* Prepare for next SNDU. */
                        reset_ule(priv);
                }

                /* More data in current TS (look at the bytes following the CRC32)? */
                if (ts_remain >= 2 && *((unsigned short *)from_where) != 0xFFFF) {
                        /* Next ULE SNDU starts right there. */
                        new_ts = 0;
                        priv->ule_skb = NULL;
                        priv->ule_sndu_type_1 = 0;
                        priv->ule_sndu_len = 0;
                        // printk(KERN_WARNING "More data in current TS: [%#x %#x %#x %#x]\n",
                        //      *(from_where + 0), *(from_where + 1),
                        //      *(from_where + 2), *(from_where + 3));
                        // printk(KERN_WARNING "ts @ %p, stopped @ %p:\n", ts, from_where + 0);
                        // hexdump(ts, 188);
                } else {
                        new_ts = 1;
                        ts += TS_SZ;
                        priv->ts_count++;
                        if (priv->ule_skb == NULL) {
                                priv->need_pusi = 1;
                                priv->ule_sndu_type_1 = 0;
                                priv->ule_sndu_len = 0;
                        }
                }
        }       /* for all available TS cells */
}

static int dvb_net_ts_callback(const u8 *buffer1, size_t buffer1_len,
                               const u8 *buffer2, size_t buffer2_len,
                               struct dmx_ts_feed *feed)
{
        struct net_device *dev = feed->priv;

        if (buffer2)
                printk(KERN_WARNING "buffer2 not NULL: %p.\n", buffer2);
        if (buffer1_len > 32768)
                printk(KERN_WARNING "length > 32k: %zu.\n", buffer1_len);
        /* printk("TS callback: %u bytes, %u TS cells @ %p.\n",
                  buffer1_len, buffer1_len / TS_SZ, buffer1); */
        dvb_net_ule(dev, buffer1, buffer1_len);
        return 0;
}


static void dvb_net_sec(struct net_device *dev,
                        const u8 *pkt, int pkt_len)
{
        u8 *eth;
        struct sk_buff *skb;
        struct net_device_stats *stats = &dev->stats;
        int snap = 0;

        /* note: pkt_len includes a 32bit checksum */
        if (pkt_len < 16) {
                printk("%s: IP/MPE packet length = %d too small.\n",
                        dev->name, pkt_len);
                stats->rx_errors++;
                stats->rx_length_errors++;
                return;
        }
/* it seems some ISPs manage to screw up here, so we have to
 * relax the error checks... */
#if 0
        if ((pkt[5] & 0xfd) != 0xc1) {
                /* drop scrambled or broken packets */
#else
        if ((pkt[5] & 0x3c) != 0x00) {
                /* drop scrambled */
#endif
                stats->rx_errors++;
                stats->rx_crc_errors++;
                return;
        }
        if (pkt[5] & 0x02) {
                /* handle LLC/SNAP, see rfc-1042 */
                if (pkt_len < 24 || memcmp(&pkt[12], "\xaa\xaa\x03\0\0\0", 6)) {
                        stats->rx_dropped++;
                        return;
                }
                snap = 8;
        }
        if (pkt[7]) {
                /* FIXME: assemble datagram from multiple sections */
                stats->rx_errors++;
                stats->rx_frame_errors++;
                return;
        }

        /* we have 14 byte ethernet header (ip header follows);
         * 12 byte MPE header; 4 byte checksum; + 2 byte alignment, 8 byte LLC/SNAP
         */
        if (!(skb = dev_alloc_skb(pkt_len - 4 - 12 + 14 + 2 - snap))) {
                //printk(KERN_NOTICE "%s: Memory squeeze, dropping packet.\n", dev->name);
                stats->rx_dropped++;
                return;
        }
        skb_reserve(skb, 2);    /* longword align L3 header */
        skb->dev = dev;

        /* copy L3 payload */
        eth = (u8 *) skb_put(skb, pkt_len - 12 - 4 + 14 - snap);
        memcpy(eth + 14, pkt + 12 + snap, pkt_len - 12 - 4 - snap);

        /* create ethernet header: */
        eth[0]=pkt[0x0b];
        eth[1]=pkt[0x0a];
        eth[2]=pkt[0x09];
        eth[3]=pkt[0x08];
        eth[4]=pkt[0x04];
        eth[5]=pkt[0x03];

        eth[6]=eth[7]=eth[8]=eth[9]=eth[10]=eth[11]=0;

        if (snap) {
                eth[12] = pkt[18];
                eth[13] = pkt[19];
        } else {
                /* protocol numbers are from rfc-1700 or
                 * http://www.iana.org/assignments/ethernet-numbers
                 */
                if (pkt[12] >> 4 == 6) { /* version field from IP header */
                        eth[12] = 0x86; /* IPv6 */
                        eth[13] = 0xdd;
                } else {
                        eth[12] = 0x08; /* IPv4 */
                        eth[13] = 0x00;
                }
        }

        skb->protocol = dvb_net_eth_type_trans(skb, dev);

        stats->rx_packets++;
        stats->rx_bytes+=skb->len;
        netif_rx(skb);
}

static int dvb_net_sec_callback(const u8 *buffer1, size_t buffer1_len,
                 const u8 *buffer2, size_t buffer2_len,
                 struct dmx_section_filter *filter)
{
        struct net_device *dev = filter->priv;

        /**
         * we rely on the DVB API definition where exactly one complete
         * section is delivered in buffer1
         */
        dvb_net_sec (dev, buffer1, buffer1_len);
        return 0;
}

static int dvb_net_tx(struct sk_buff *skb, struct net_device *dev)
{
        dev_kfree_skb(skb);
        return NETDEV_TX_OK;
}

static u8 mask_normal[6]={0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
static u8 mask_allmulti[6]={0xff, 0xff, 0xff, 0x00, 0x00, 0x00};
static u8 mac_allmulti[6]={0x01, 0x00, 0x5e, 0x00, 0x00, 0x00};
static u8 mask_promisc[6]={0x00, 0x00, 0x00, 0x00, 0x00, 0x00};

static int dvb_net_filter_sec_set(struct net_device *dev,
                   struct dmx_section_filter **secfilter,
                   u8 *mac, u8 *mac_mask)
{
        struct dvb_net_priv *priv = netdev_priv(dev);
        int ret;

        *secfilter=NULL;
        ret = priv->secfeed->allocate_filter(priv->secfeed, secfilter);
        if (ret<0) {
                printk("%s: could not get filter\n", dev->name);
                return ret;
        }

        (*secfilter)->priv=(void *) dev;

        memset((*secfilter)->filter_value, 0x00, DMX_MAX_FILTER_SIZE);
        memset((*secfilter)->filter_mask,  0x00, DMX_MAX_FILTER_SIZE);
        memset((*secfilter)->filter_mode,  0xff, DMX_MAX_FILTER_SIZE);

        (*secfilter)->filter_value[0]=0x3e;
        (*secfilter)->filter_value[3]=mac[5];
        (*secfilter)->filter_value[4]=mac[4];
        (*secfilter)->filter_value[8]=mac[3];
        (*secfilter)->filter_value[9]=mac[2];
        (*secfilter)->filter_value[10]=mac[1];
        (*secfilter)->filter_value[11]=mac[0];

        (*secfilter)->filter_mask[0] = 0xff;
        (*secfilter)->filter_mask[3] = mac_mask[5];
        (*secfilter)->filter_mask[4] = mac_mask[4];
        (*secfilter)->filter_mask[8] = mac_mask[3];
        (*secfilter)->filter_mask[9] = mac_mask[2];
        (*secfilter)->filter_mask[10] = mac_mask[1];
        (*secfilter)->filter_mask[11]=mac_mask[0];

        netdev_dbg(dev, "filter mac=%pM mask=%pM\n", mac, mac_mask);

        return 0;
}

static int dvb_net_feed_start(struct net_device *dev)
{
        int ret = 0, i;
        struct dvb_net_priv *priv = netdev_priv(dev);
        struct dmx_demux *demux = priv->demux;
        unsigned char *mac = (unsigned char *) dev->dev_addr;

        netdev_dbg(dev, "rx_mode %i\n", priv->rx_mode);
        mutex_lock(&priv->mutex);
        if (priv->tsfeed || priv->secfeed || priv->secfilter || priv->multi_secfilter[0])
                printk("%s: BUG %d\n", __func__, __LINE__);

        priv->secfeed=NULL;
        priv->secfilter=NULL;
        priv->tsfeed = NULL;

        if (priv->feedtype == DVB_NET_FEEDTYPE_MPE) {
                netdev_dbg(dev, "alloc secfeed\n");
                ret=demux->allocate_section_feed(demux, &priv->secfeed,
                                         dvb_net_sec_callback);
                if (ret<0) {
                        printk("%s: could not allocate section feed\n", dev->name);
                        goto error;
                }

                ret = priv->secfeed->set(priv->secfeed, priv->pid, 32768, 1);

                if (ret<0) {
                        printk("%s: could not set section feed\n", dev->name);
                        priv->demux->release_section_feed(priv->demux, priv->secfeed);
                        priv->secfeed=NULL;
                        goto error;
                }

                if (priv->rx_mode != RX_MODE_PROMISC) {
                        netdev_dbg(dev, "set secfilter\n");
                        dvb_net_filter_sec_set(dev, &priv->secfilter, mac, mask_normal);
                }

                switch (priv->rx_mode) {
                case RX_MODE_MULTI:
                        for (i = 0; i < priv->multi_num; i++) {
                                netdev_dbg(dev, "set multi_secfilter[%d]\n", i);
                                dvb_net_filter_sec_set(dev, &priv->multi_secfilter[i],
                                                       priv->multi_macs[i], mask_normal);
                        }
                        break;
                case RX_MODE_ALL_MULTI:
                        priv->multi_num=1;
                        netdev_dbg(dev, "set multi_secfilter[0]\n");
                        dvb_net_filter_sec_set(dev, &priv->multi_secfilter[0],
                                               mac_allmulti, mask_allmulti);
                        break;
                case RX_MODE_PROMISC:
                        priv->multi_num=0;
                        netdev_dbg(dev, "set secfilter\n");
                        dvb_net_filter_sec_set(dev, &priv->secfilter, mac, mask_promisc);
                        break;
                }

                netdev_dbg(dev, "start filtering\n");
                priv->secfeed->start_filtering(priv->secfeed);
        } else if (priv->feedtype == DVB_NET_FEEDTYPE_ULE) {
                struct timespec timeout = { 0, 10000000 }; // 10 msec

                /* we have payloads encapsulated in TS */
                netdev_dbg(dev, "alloc tsfeed\n");
                ret = demux->allocate_ts_feed(demux, &priv->tsfeed, dvb_net_ts_callback);
                if (ret < 0) {
                        printk("%s: could not allocate ts feed\n", dev->name);
                        goto error;
                }

                /* Set netdevice pointer for ts decaps callback. */
                priv->tsfeed->priv = (void *)dev;
                ret = priv->tsfeed->set(priv->tsfeed,
                                        priv->pid, /* pid */
                                        TS_PACKET, /* type */
                                        DMX_PES_OTHER, /* pes type */
                                        32768,     /* circular buffer size */
                                        timeout    /* timeout */
                                        );

                if (ret < 0) {
                        printk("%s: could not set ts feed\n", dev->name);
                        priv->demux->release_ts_feed(priv->demux, priv->tsfeed);
                        priv->tsfeed = NULL;
                        goto error;
                }

                netdev_dbg(dev, "start filtering\n");
                priv->tsfeed->start_filtering(priv->tsfeed);
        } else
                ret = -EINVAL;

error:
        mutex_unlock(&priv->mutex);
        return ret;
}

static int dvb_net_feed_stop(struct net_device *dev)
{
        struct dvb_net_priv *priv = netdev_priv(dev);
        int i, ret = 0;

        mutex_lock(&priv->mutex);
        if (priv->feedtype == DVB_NET_FEEDTYPE_MPE) {
                if (priv->secfeed) {
                        if (priv->secfeed->is_filtering) {
                                netdev_dbg(dev, "stop secfeed\n");
                                priv->secfeed->stop_filtering(priv->secfeed);
                        }

                        if (priv->secfilter) {
                                netdev_dbg(dev, "release secfilter\n");
                                priv->secfeed->release_filter(priv->secfeed,
                                                              priv->secfilter);
                                priv->secfilter=NULL;
                        }

                        for (i=0; i<priv->multi_num; i++) {
                                if (priv->multi_secfilter[i]) {
                                        netdev_dbg(dev, "release multi_filter[%d]\n",
                                                   i);
                                        priv->secfeed->release_filter(priv->secfeed,
                                                                      priv->multi_secfilter[i]);
                                        priv->multi_secfilter[i] = NULL;
                                }
                        }

                        priv->demux->release_section_feed(priv->demux, priv->secfeed);
                        priv->secfeed = NULL;
                } else
                        printk("%s: no feed to stop\n", dev->name);
        } else if (priv->feedtype == DVB_NET_FEEDTYPE_ULE) {
                if (priv->tsfeed) {
                        if (priv->tsfeed->is_filtering) {
                                netdev_dbg(dev, "stop tsfeed\n");
                                priv->tsfeed->stop_filtering(priv->tsfeed);
                        }
                        priv->demux->release_ts_feed(priv->demux, priv->tsfeed);
                        priv->tsfeed = NULL;
                }
                else
                        printk("%s: no ts feed to stop\n", dev->name);
        } else
                ret = -EINVAL;
        mutex_unlock(&priv->mutex);
        return ret;
}


static int dvb_set_mc_filter(struct net_device *dev, unsigned char *addr)
{
        struct dvb_net_priv *priv = netdev_priv(dev);

        if (priv->multi_num == DVB_NET_MULTICAST_MAX)
                return -ENOMEM;

        memcpy(priv->multi_macs[priv->multi_num], addr, ETH_ALEN);

        priv->multi_num++;
        return 0;
}


static void wq_set_multicast_list (struct work_struct *work)
{
        struct dvb_net_priv *priv =
                container_of(work, struct dvb_net_priv, set_multicast_list_wq);
        struct net_device *dev = priv->net;

        dvb_net_feed_stop(dev);
        priv->rx_mode = RX_MODE_UNI;
        netif_addr_lock_bh(dev);

        if (dev->flags & IFF_PROMISC) {
                netdev_dbg(dev, "promiscuous mode\n");
                priv->rx_mode = RX_MODE_PROMISC;
        } else if ((dev->flags & IFF_ALLMULTI)) {
                netdev_dbg(dev, "allmulti mode\n");
                priv->rx_mode = RX_MODE_ALL_MULTI;
        } else if (!netdev_mc_empty(dev)) {
                struct netdev_hw_addr *ha;

                netdev_dbg(dev, "set_mc_list, %d entries\n",
                           netdev_mc_count(dev));

                priv->rx_mode = RX_MODE_MULTI;
                priv->multi_num = 0;

                netdev_for_each_mc_addr(ha, dev)
                        dvb_set_mc_filter(dev, ha->addr);
        }

        netif_addr_unlock_bh(dev);
        dvb_net_feed_start(dev);
}


static void dvb_net_set_multicast_list (struct net_device *dev)
{
        struct dvb_net_priv *priv = netdev_priv(dev);
        schedule_work(&priv->set_multicast_list_wq);
}


static void wq_restart_net_feed (struct work_struct *work)
{
        struct dvb_net_priv *priv =
                container_of(work, struct dvb_net_priv, restart_net_feed_wq);
        struct net_device *dev = priv->net;

        if (netif_running(dev)) {
                dvb_net_feed_stop(dev);
                dvb_net_feed_start(dev);
        }
}


static int dvb_net_set_mac (struct net_device *dev, void *p)
{
        struct dvb_net_priv *priv = netdev_priv(dev);
        struct sockaddr *addr=p;

        memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);

        if (netif_running(dev))
                schedule_work(&priv->restart_net_feed_wq);

        return 0;
}


static int dvb_net_open(struct net_device *dev)
{
        struct dvb_net_priv *priv = netdev_priv(dev);

        priv->in_use++;
        dvb_net_feed_start(dev);
        return 0;
}


static int dvb_net_stop(struct net_device *dev)
{
        struct dvb_net_priv *priv = netdev_priv(dev);

        priv->in_use--;
        return dvb_net_feed_stop(dev);
}

static const struct header_ops dvb_header_ops = {
        .create         = eth_header,
        .parse          = eth_header_parse,
};


static const struct net_device_ops dvb_netdev_ops = {
        .ndo_open               = dvb_net_open,
        .ndo_stop               = dvb_net_stop,
        .ndo_start_xmit         = dvb_net_tx,
        .ndo_set_rx_mode        = dvb_net_set_multicast_list,
        .ndo_set_mac_address    = dvb_net_set_mac,
        .ndo_change_mtu         = eth_change_mtu,
        .ndo_validate_addr      = eth_validate_addr,
};

static void dvb_net_setup(struct net_device *dev)
{
        ether_setup(dev);

        dev->header_ops         = &dvb_header_ops;
        dev->netdev_ops         = &dvb_netdev_ops;
        dev->mtu                = 4096;

        dev->flags |= IFF_NOARP;
}

static int get_if(struct dvb_net *dvbnet)
{
        int i;

        for (i=0; i<DVB_NET_DEVICES_MAX; i++)
                if (!dvbnet->state[i])
                        break;

        if (i == DVB_NET_DEVICES_MAX)
                return -1;

        dvbnet->state[i]=1;
        return i;
}

static int dvb_net_add_if(struct dvb_net *dvbnet, u16 pid, u8 feedtype)
{
        struct net_device *net;
        struct dvb_net_priv *priv;
        int result;
        int if_num;

        if (feedtype != DVB_NET_FEEDTYPE_MPE && feedtype != DVB_NET_FEEDTYPE_ULE)
                return -EINVAL;
        if ((if_num = get_if(dvbnet)) < 0)
                return -EINVAL;

        net = alloc_netdev(sizeof(struct dvb_net_priv), "dvb",
                           NET_NAME_UNKNOWN, dvb_net_setup);
        if (!net)
                return -ENOMEM;

        if (dvbnet->dvbdev->id)
                snprintf(net->name, IFNAMSIZ, "dvb%d%u%d",
                         dvbnet->dvbdev->adapter->num, dvbnet->dvbdev->id, if_num);
        else
                /* compatibility fix to keep dvb0_0 format */
                snprintf(net->name, IFNAMSIZ, "dvb%d_%d",
                         dvbnet->dvbdev->adapter->num, if_num);

        net->addr_len = 6;
        memcpy(net->dev_addr, dvbnet->dvbdev->adapter->proposed_mac, 6);

        dvbnet->device[if_num] = net;

        priv = netdev_priv(net);
        priv->net = net;
        priv->demux = dvbnet->demux;
        priv->pid = pid;
        priv->rx_mode = RX_MODE_UNI;
        priv->need_pusi = 1;
        priv->tscc = 0;
        priv->feedtype = feedtype;
        reset_ule(priv);

        INIT_WORK(&priv->set_multicast_list_wq, wq_set_multicast_list);
        INIT_WORK(&priv->restart_net_feed_wq, wq_restart_net_feed);
        mutex_init(&priv->mutex);

        net->base_addr = pid;

        if ((result = register_netdev(net)) < 0) {
                dvbnet->device[if_num] = NULL;
                free_netdev(net);
                return result;
        }
        printk("dvb_net: created network interface %s\n", net->name);

        return if_num;
}

static int dvb_net_remove_if(struct dvb_net *dvbnet, unsigned long num)
{
        struct net_device *net = dvbnet->device[num];
        struct dvb_net_priv *priv;

        if (!dvbnet->state[num])
                return -EINVAL;
        priv = netdev_priv(net);
        if (priv->in_use)
                return -EBUSY;

        dvb_net_stop(net);
        flush_work(&priv->set_multicast_list_wq);
        flush_work(&priv->restart_net_feed_wq);
        printk("dvb_net: removed network interface %s\n", net->name);
        unregister_netdev(net);
        dvbnet->state[num]=0;
        dvbnet->device[num] = NULL;
        free_netdev(net);

        return 0;
}

static int dvb_net_do_ioctl(struct file *file,
                  unsigned int cmd, void *parg)
{
        struct dvb_device *dvbdev = file->private_data;
        struct dvb_net *dvbnet = dvbdev->priv;
        int ret = 0;

        if (((file->f_flags&O_ACCMODE)==O_RDONLY))
                return -EPERM;

        if (mutex_lock_interruptible(&dvbnet->ioctl_mutex))
                return -ERESTARTSYS;

        switch (cmd) {
        case NET_ADD_IF:
        {
                struct dvb_net_if *dvbnetif = parg;
                int result;

                if (!capable(CAP_SYS_ADMIN)) {
                        ret = -EPERM;
                        goto ioctl_error;
                }

                if (!try_module_get(dvbdev->adapter->module)) {
                        ret = -EPERM;
                        goto ioctl_error;
                }

                result=dvb_net_add_if(dvbnet, dvbnetif->pid, dvbnetif->feedtype);
                if (result<0) {
                        module_put(dvbdev->adapter->module);
                        ret = result;
                        goto ioctl_error;
                }
                dvbnetif->if_num=result;
                break;
        }
        case NET_GET_IF:
        {
                struct net_device *netdev;
                struct dvb_net_priv *priv_data;
                struct dvb_net_if *dvbnetif = parg;

                if (dvbnetif->if_num >= DVB_NET_DEVICES_MAX ||
                    !dvbnet->state[dvbnetif->if_num]) {
                        ret = -EINVAL;
                        goto ioctl_error;
                }

                netdev = dvbnet->device[dvbnetif->if_num];

                priv_data = netdev_priv(netdev);
                dvbnetif->pid=priv_data->pid;
                dvbnetif->feedtype=priv_data->feedtype;
                break;
        }
        case NET_REMOVE_IF:
        {
                if (!capable(CAP_SYS_ADMIN)) {
                        ret = -EPERM;
                        goto ioctl_error;
                }
                if ((unsigned long) parg >= DVB_NET_DEVICES_MAX) {
                        ret = -EINVAL;
                        goto ioctl_error;
                }
                ret = dvb_net_remove_if(dvbnet, (unsigned long) parg);
                if (!ret)
                        module_put(dvbdev->adapter->module);
                break;
        }

        /* binary compatibility cruft */
        case __NET_ADD_IF_OLD:
        {
                struct __dvb_net_if_old *dvbnetif = parg;
                int result;

                if (!capable(CAP_SYS_ADMIN)) {
                        ret = -EPERM;
                        goto ioctl_error;
                }

                if (!try_module_get(dvbdev->adapter->module)) {
                        ret = -EPERM;
                        goto ioctl_error;
                }

                result=dvb_net_add_if(dvbnet, dvbnetif->pid, DVB_NET_FEEDTYPE_MPE);
                if (result<0) {
                        module_put(dvbdev->adapter->module);
                        ret = result;
                        goto ioctl_error;
                }
                dvbnetif->if_num=result;
                break;
        }
        case __NET_GET_IF_OLD:
        {
                struct net_device *netdev;
                struct dvb_net_priv *priv_data;
                struct __dvb_net_if_old *dvbnetif = parg;

                if (dvbnetif->if_num >= DVB_NET_DEVICES_MAX ||
                    !dvbnet->state[dvbnetif->if_num]) {
                        ret = -EINVAL;
                        goto ioctl_error;
                }

                netdev = dvbnet->device[dvbnetif->if_num];

                priv_data = netdev_priv(netdev);
                dvbnetif->pid=priv_data->pid;
                break;
        }
        default:
                ret = -ENOTTY;
                break;
        }

ioctl_error:
        mutex_unlock(&dvbnet->ioctl_mutex);
        return ret;
}

static long dvb_net_ioctl(struct file *file,
              unsigned int cmd, unsigned long arg)
{
        return dvb_usercopy(file, cmd, arg, dvb_net_do_ioctl);
}

static int dvb_net_close(struct inode *inode, struct file *file)
{
        struct dvb_device *dvbdev = file->private_data;
        struct dvb_net *dvbnet = dvbdev->priv;

        dvb_generic_release(inode, file);

        if(dvbdev->users == 1 && dvbnet->exit == 1)
                wake_up(&dvbdev->wait_queue);
        return 0;
}


static const struct file_operations dvb_net_fops = {
        .owner = THIS_MODULE,
        .unlocked_ioctl = dvb_net_ioctl,
        .open = dvb_generic_open,
        .release = dvb_net_close,
        .llseek = noop_llseek,
};

static const struct dvb_device dvbdev_net = {
        .priv = NULL,
        .users = 1,
        .writers = 1,
#if defined(CONFIG_MEDIA_CONTROLLER_DVB)
        .name = "dvb-net",
#endif
        .fops = &dvb_net_fops,
};

void dvb_net_release (struct dvb_net *dvbnet)
{
        int i;

        dvbnet->exit = 1;
        if (dvbnet->dvbdev->users < 1)
                wait_event(dvbnet->dvbdev->wait_queue,
                                dvbnet->dvbdev->users==1);

        dvb_unregister_device(dvbnet->dvbdev);

        for (i=0; i<DVB_NET_DEVICES_MAX; i++) {
                if (!dvbnet->state[i])
                        continue;
                dvb_net_remove_if(dvbnet, i);
        }
}
EXPORT_SYMBOL(dvb_net_release);


int dvb_net_init (struct dvb_adapter *adap, struct dvb_net *dvbnet,
                  struct dmx_demux *dmx)
{
        int i;

        mutex_init(&dvbnet->ioctl_mutex);
        dvbnet->demux = dmx;

        for (i=0; i<DVB_NET_DEVICES_MAX; i++)
                dvbnet->state[i] = 0;

        return dvb_register_device(adap, &dvbnet->dvbdev, &dvbdev_net,
                             dvbnet, DVB_DEVICE_NET, 0);
}
EXPORT_SYMBOL(dvb_net_init);