Merge with 2.3.99-pre1.

[linux-2.6/linux-mips.git] / net / packet / af_packet.c

/*
 * INET         An implementation of the TCP/IP protocol suite for the LINUX
 *              operating system.  INET is implemented using the  BSD Socket
 *              interface as the means of communication with the user level.
 *
 *              PACKET - implements raw packet sockets.
 *
 * Version:     $Id: af_packet.c,v 1.33 2000/03/13 22:11:50 davem Exp $
 *
 * Authors:     Ross Biro, <bir7@leland.Stanford.Edu>
 *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *              Alan Cox, <gw4pts@gw4pts.ampr.org>
 *
 * Fixes:       
 *              Alan Cox        :       verify_area() now used correctly
 *              Alan Cox        :       new skbuff lists, look ma no backlogs!
 *              Alan Cox        :       tidied skbuff lists.
 *              Alan Cox        :       Now uses generic datagram routines I
 *                                      added. Also fixed the peek/read crash
 *                                      from all old Linux datagram code.
 *              Alan Cox        :       Uses the improved datagram code.
 *              Alan Cox        :       Added NULL's for socket options.
 *              Alan Cox        :       Re-commented the code.
 *              Alan Cox        :       Use new kernel side addressing
 *              Rob Janssen     :       Correct MTU usage.
 *              Dave Platt      :       Counter leaks caused by incorrect
 *                                      interrupt locking and some slightly
 *                                      dubious gcc output. Can you read
 *                                      compiler: it said _VOLATILE_
 *      Richard Kooijman        :       Timestamp fixes.
 *              Alan Cox        :       New buffers. Use sk->mac.raw.
 *              Alan Cox        :       sendmsg/recvmsg support.
 *              Alan Cox        :       Protocol setting support
 *      Alexey Kuznetsov        :       Untied from IPv4 stack.
 *      Cyrus Durgin            :       Fixed kerneld for kmod.
 *
 *              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.
 *
 */
 
#include <linux/config.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_packet.h>
#include <linux/wireless.h>
#include <linux/kmod.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <linux/proc_fs.h>
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/if_bridge.h>

#ifdef CONFIG_INET
#include <net/inet_common.h>
#endif

#ifdef CONFIG_DLCI
extern int dlci_ioctl(unsigned int, void*);
#endif

/*
   Old SOCK_PACKET. Do exist programs, which use it?
   (not counting tcpdump) - lots of them yes - AC. 
   
 */
#define CONFIG_SOCK_PACKET      1

/*
   Proposed replacement for SIOC{ADD,DEL}MULTI and
   IFF_PROMISC, IFF_ALLMULTI flags.

   It is more expensive, but I believe,
   it is really correct solution: reentereble, safe and fault tolerant.

   Differences:
   - Changing IFF_ALLMULTI from user level is disabled.
     It could only confused multicast routing daemons, not more.
   - IFF_PROMISC is faked by keeping reference count and
     global flag, so that real IFF_PROMISC == (gflag|(count != 0))
     I'd remove it too, but it would require recompilation tcpdump
     and another applications, using promiscuous mode.
   - SIOC{ADD/DEL}MULTI are moved to deprecated state,
     they work, but complain. I do know who uses them.
     
 
*************FIXME***************
  Alexey : This doesnt cook Im afraid. We need the low level SIOCADD/DELMULTI
  and also IFF_ALLMULTI for DECNET, Appletalk and other stuff as well as
  BSD compatibility issues.
  
 */
#define CONFIG_PACKET_MULTICAST 1

/*
   Assumptions:
   - if device has no dev->hard_header routine, it adds and removes ll header
     inside itself. In this case ll header is invisible outside of device,
     but higher levels still should reserve dev->hard_header_len.
     Some devices are enough clever to reallocate skb, when header
     will not fit to reserved space (tunnel), another ones are silly
     (PPP).
   - packet socket receives packets with pulled ll header,
     so that SOCK_RAW should push it back.

On receive:
-----------

Incoming, dev->hard_header!=NULL
   mac.raw -> ll header
   data    -> data

Outgoing, dev->hard_header!=NULL
   mac.raw -> ll header
   data    -> ll header

Incoming, dev->hard_header==NULL
   mac.raw -> UNKNOWN position. It is very likely, that it points to ll header.
              PPP makes it, that is wrong, because introduce assymetry
              between rx and tx paths.
   data    -> data

Outgoing, dev->hard_header==NULL
   mac.raw -> data. ll header is still not built!
   data    -> data

Resume
  If dev->hard_header==NULL we are unlikely to restore sensible ll header.


On transmit:
------------

dev->hard_header != NULL
   mac.raw -> ll header
   data    -> ll header

dev->hard_header == NULL (ll header is added by device, we cannot control it)
   mac.raw -> data
   data -> data

   We should set nh.raw on output to correct posistion,
   packet classifier depends on it.
 */

/* List of all packet sockets. */
static struct sock * packet_sklist = NULL;
static rwlock_t packet_sklist_lock = RW_LOCK_UNLOCKED;

atomic_t packet_socks_nr;


/* Private packet socket structures. */

#ifdef CONFIG_PACKET_MULTICAST
struct packet_mclist
{
        struct packet_mclist    *next;
        int                     ifindex;
        int                     count;
        unsigned short          type;
        unsigned short          alen;
        unsigned char           addr[8];
};
#endif
#ifdef CONFIG_PACKET_MMAP
static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing);
#endif

static void packet_flush_mclist(struct sock *sk);

struct packet_opt
{
        struct packet_type      prot_hook;
        spinlock_t              bind_lock;
        char                    running;        /* prot_hook is attached*/
        int                     ifindex;        /* bound device         */
        struct tpacket_stats    stats;
#ifdef CONFIG_PACKET_MULTICAST
        struct packet_mclist    *mclist;
#endif
#ifdef CONFIG_PACKET_MMAP
        atomic_t                mapped;
        unsigned long           *pg_vec;
        unsigned int            pg_vec_order;
        unsigned int            pg_vec_pages;
        unsigned int            pg_vec_len;

        struct tpacket_hdr      **iovec;
        unsigned int            frame_size;
        unsigned int            iovmax;
        unsigned int            head;
#endif
};

void packet_sock_destruct(struct sock *sk)
{
        BUG_TRAP(atomic_read(&sk->rmem_alloc)==0);
        BUG_TRAP(atomic_read(&sk->wmem_alloc)==0);

        if (!sk->dead) {
                printk("Attempt to release alive packet socket: %p\n", sk);
                return;
        }

        if (sk->protinfo.destruct_hook)
                kfree(sk->protinfo.destruct_hook);
        atomic_dec(&packet_socks_nr);
#ifdef PACKET_REFCNT_DEBUG
        printk(KERN_DEBUG "PACKET socket %p is free, %d are alive\n", sk, atomic_read(&packet_socks_nr));
#endif
        MOD_DEC_USE_COUNT;
}


extern struct proto_ops packet_ops;

#ifdef CONFIG_SOCK_PACKET
extern struct proto_ops packet_ops_spkt;

static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,  struct packet_type *pt)
{
        struct sock *sk;
        struct sockaddr_pkt *spkt;

        /*
         *      When we registered the protocol we saved the socket in the data
         *      field for just this event.
         */

        sk = (struct sock *) pt->data;
        
        /*
         *      Yank back the headers [hope the device set this
         *      right or kerboom...]
         *
         *      Incoming packets have ll header pulled,
         *      push it back.
         *
         *      For outgoing ones skb->data == skb->mac.raw
         *      so that this procedure is noop.
         */

        if (skb->pkt_type == PACKET_LOOPBACK)
                goto out;

        if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
                goto oom;

        spkt = (struct sockaddr_pkt*)skb->cb;

        skb_push(skb, skb->data-skb->mac.raw);

        /*
         *      The SOCK_PACKET socket receives _all_ frames.
         */

        spkt->spkt_family = dev->type;
        strncpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
        spkt->spkt_protocol = skb->protocol;

        if (skb->rx_dev) {
                dev_put(skb->rx_dev);
                skb->rx_dev = NULL;
        }

        /*
         *      Charge the memory to the socket. This is done specifically
         *      to prevent sockets using all the memory up.
         */

        if (sock_queue_rcv_skb(sk,skb) == 0)
                return 0;

out:
        kfree_skb(skb);
oom:
        return 0;
}


/*
 *      Output a raw packet to a device layer. This bypasses all the other
 *      protocol layers and you must therefore supply it with a complete frame
 */
 
static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg, int len,
                               struct scm_cookie *scm)
{
        struct sock *sk = sock->sk;
        struct sockaddr_pkt *saddr=(struct sockaddr_pkt *)msg->msg_name;
        struct sk_buff *skb;
        struct net_device *dev;
        unsigned short proto=0;
        int err;
        
        /*
         *      Get and verify the address. 
         */

        if (saddr)
        {
                if (msg->msg_namelen < sizeof(struct sockaddr))
                        return(-EINVAL);
                if (msg->msg_namelen==sizeof(struct sockaddr_pkt))
                        proto=saddr->spkt_protocol;
        }
        else
                return(-ENOTCONN);      /* SOCK_PACKET must be sent giving an address */

        /*
         *      Find the device first to size check it 
         */

        saddr->spkt_device[13] = 0;
        dev = dev_get_by_name(saddr->spkt_device);
        err = -ENODEV;
        if (dev == NULL)
                goto out_unlock;
        
        /*
         *      You may not queue a frame bigger than the mtu. This is the lowest level
         *      raw protocol and you must do your own fragmentation at this level.
         */
         
        err = -EMSGSIZE;
        if(len>dev->mtu+dev->hard_header_len)
                goto out_unlock;

        err = -ENOBUFS;
        skb = sock_wmalloc(sk, len+dev->hard_header_len+15, 0, GFP_KERNEL);

        /*
         *      If the write buffer is full, then tough. At this level the user gets to
         *      deal with the problem - do your own algorithmic backoffs. That's far
         *      more flexible.
         */
         
        if (skb == NULL) 
                goto out_unlock;

        /*
         *      Fill it in 
         */
         
        /* FIXME: Save some space for broken drivers that write a
         * hard header at transmission time by themselves. PPP is the
         * notable one here. This should really be fixed at the driver level.
         */
        skb_reserve(skb,(dev->hard_header_len+15)&~15);
        skb->nh.raw = skb->data;

        /* Try to align data part correctly */
        if (dev->hard_header) {
                skb->data -= dev->hard_header_len;
                skb->tail -= dev->hard_header_len;
        }

        /* Returns -EFAULT on error */
        err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
        skb->protocol = proto;
        skb->dev = dev;
        skb->priority = sk->priority;
        if (err)
                goto out_free;

        err = -ENETDOWN;
        if (!(dev->flags & IFF_UP))
                goto out_free;

        /*
         *      Now send it
         */

        dev_queue_xmit(skb);
        dev_put(dev);
        return(len);

out_free:
        kfree_skb(skb);
out_unlock:
        if (dev)
                dev_put(dev);
        return err;
}
#endif

/*
   This function makes lazy skb cloning in hope that most of packets
   are discarded by BPF.

   Note tricky part: we DO mangle shared skb! skb->data, skb->len
   and skb->cb are mangled. It works because (and until) packets
   falling here are owned by current CPU. Output packets are cloned
   by dev_queue_xmit_nit(), input packets are processed by net_bh
   sequencially, so that if we return skb to original state on exit,
   we will not harm anyone.
 */

static int packet_rcv(struct sk_buff *skb, struct net_device *dev,  struct packet_type *pt)
{
        struct sock *sk;
        struct sockaddr_ll *sll;
        struct packet_opt *po;
        u8 * skb_head = skb->data;
#ifdef CONFIG_FILTER
        unsigned snaplen;
#endif

        if (skb->pkt_type == PACKET_LOOPBACK)
                goto drop;

        sk = (struct sock *) pt->data;
        po = sk->protinfo.af_packet;

        skb->dev = dev;

        if (dev->hard_header) {
                /* The device has an explicit notion of ll header,
                   exported to higher levels.

                   Otherwise, the device hides datails of it frame
                   structure, so that corresponding packet head
                   never delivered to user.
                 */
                if (sk->type != SOCK_DGRAM)
                        skb_push(skb, skb->data - skb->mac.raw);
                else if (skb->pkt_type == PACKET_OUTGOING) {
                        /* Special case: outgoing packets have ll header at head */
                        skb_pull(skb, skb->nh.raw - skb->data);
                }
        }

#ifdef CONFIG_FILTER
        snaplen = skb->len;

        if (sk->filter) {
                unsigned res = snaplen;
                struct sk_filter *filter;

                bh_lock_sock(sk);
                if ((filter = sk->filter) != NULL)
                        res = sk_run_filter(skb, sk->filter->insns, sk->filter->len);
                bh_unlock_sock(sk);

                if (res == 0)
                        goto drop_n_restore;
                if (snaplen > res)
                        snaplen = res;
        }
#endif /* CONFIG_FILTER */

        if (atomic_read(&sk->rmem_alloc) + skb->truesize >= (unsigned)sk->rcvbuf)
                goto drop_n_acct;

        if (skb_shared(skb)) {
                struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
                if (nskb == NULL)
                        goto drop_n_acct;

                if (skb_head != skb->data) {
                        skb->data = skb_head;
                        skb->len = skb->tail - skb->data;
                }
                kfree_skb(skb);
                skb = nskb;
        }

        sll = (struct sockaddr_ll*)skb->cb;
        sll->sll_family = AF_PACKET;
        sll->sll_hatype = dev->type;
        sll->sll_protocol = skb->protocol;
        sll->sll_pkttype = skb->pkt_type;
        sll->sll_ifindex = dev->ifindex;
        sll->sll_halen = 0;

        if (dev->hard_header_parse)
                sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);

        if (skb->rx_dev) {
                dev_put(skb->rx_dev);
                skb->rx_dev = NULL;
        }

#ifdef CONFIG_FILTER
        if (skb->len > snaplen)
                __skb_trim(skb, snaplen);
#endif

        skb_set_owner_r(skb, sk);
        spin_lock(&sk->receive_queue.lock);
        po->stats.tp_packets++;
        __skb_queue_tail(&sk->receive_queue, skb);
        spin_unlock(&sk->receive_queue.lock);
        sk->data_ready(sk,skb->len);
        return 0;

drop_n_acct:
        spin_lock(&sk->receive_queue.lock);
        po->stats.tp_drops++;
        spin_unlock(&sk->receive_queue.lock);

#ifdef CONFIG_FILTER
drop_n_restore:
#endif
        if (skb_head != skb->data && skb_shared(skb)) {
                skb->data = skb_head;
                skb->len = skb->tail - skb->data;
        }
drop:
        kfree_skb(skb);
        return 0;
}

#ifdef CONFIG_PACKET_MMAP
static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,  struct packet_type *pt)
{
        struct sock *sk;
        struct packet_opt *po;
        struct sockaddr_ll *sll;
        struct tpacket_hdr *h;
        u8 * skb_head = skb->data;
        unsigned snaplen;
        unsigned long losing;

        if (skb->pkt_type == PACKET_LOOPBACK)
                goto drop;

        sk = (struct sock *) pt->data;
        po = sk->protinfo.af_packet;

        if (dev->hard_header) {
                if (sk->type != SOCK_DGRAM)
                        skb_push(skb, skb->data - skb->mac.raw);
                else if (skb->pkt_type == PACKET_OUTGOING) {
                        /* Special case: outgoing packets have ll header at head */
                        skb_pull(skb, skb->nh.raw - skb->data);
                }
        }

        snaplen = skb->len;

#ifdef CONFIG_FILTER
        if (sk->filter) {
                unsigned res = snaplen;
                struct sk_filter *filter;

                bh_lock_sock(sk);
                if ((filter = sk->filter) != NULL)
                        res = sk_run_filter(skb, sk->filter->insns, sk->filter->len);
                bh_unlock_sock(sk);

                if (res == 0)
                        goto drop_n_restore;
                if (snaplen > res)
                        snaplen = res;
        }
#endif
        spin_lock(&sk->receive_queue.lock);
        h = po->iovec[po->head];

        if (h->tp_status)
                goto ring_is_full;
        po->head = po->head != po->iovmax ? po->head+1 : 0;
        po->stats.tp_packets++;
        losing = TP_STATUS_LOSING;
        if (!po->stats.tp_drops)
                losing = 0;
        spin_unlock(&sk->receive_queue.lock);

        if (sk->type == SOCK_DGRAM) {
                h->tp_mac = h->tp_net = TPACKET_ALIGN(TPACKET_HDRLEN) + 16;
        } else {
                unsigned maclen = skb->nh.raw - skb->data;
                h->tp_net = TPACKET_ALIGN(TPACKET_HDRLEN + (maclen < 16 ? 16 : maclen));
                h->tp_mac = h->tp_net - maclen;
        }

        if (h->tp_mac + snaplen > po->frame_size) {
                snaplen = po->frame_size - h->tp_mac;
                if ((int)snaplen < 0)
                        snaplen = 0;
        }

        memcpy((u8*)h + h->tp_mac, skb->data, snaplen);

        h->tp_sec = skb->stamp.tv_sec;
        h->tp_usec = skb->stamp.tv_usec;
        h->tp_len = skb->len;
        h->tp_snaplen = snaplen;

        sll = (struct sockaddr_ll*)((u8*)h + TPACKET_ALIGN(sizeof(*h)));
        sll->sll_halen = 0;
        if (dev->hard_header_parse)
                sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
        sll->sll_family = AF_PACKET;
        sll->sll_hatype = dev->type;
        sll->sll_protocol = skb->protocol;
        sll->sll_pkttype = skb->pkt_type;
        sll->sll_ifindex = dev->ifindex;

        h->tp_status = losing|TP_STATUS_USER;
        mb();

        sk->data_ready(sk, 0);

drop_n_restore:
        if (skb_head != skb->data && skb_shared(skb)) {
                skb->data = skb_head;
                skb->len = skb->tail - skb->data;
        }
drop:
        kfree_skb(skb);
        return 0;

ring_is_full:
        po->stats.tp_drops++;
        spin_unlock(&sk->receive_queue.lock);

        sk->data_ready(sk, 0);
        goto drop_n_restore;
}

#endif


static int packet_sendmsg(struct socket *sock, struct msghdr *msg, int len,
                          struct scm_cookie *scm)
{
        struct sock *sk = sock->sk;
        struct sockaddr_ll *saddr=(struct sockaddr_ll *)msg->msg_name;
        struct sk_buff *skb;
        struct net_device *dev;
        unsigned short proto;
        unsigned char *addr;
        int ifindex, err, reserve = 0;

        /*
         *      Get and verify the address. 
         */
         
        if (saddr == NULL) {
                ifindex = sk->protinfo.af_packet->ifindex;
                proto   = sk->num;
                addr    = NULL;
        } else {
                err = -EINVAL;
                if (msg->msg_namelen < sizeof(struct sockaddr_ll))
                        goto out;
                ifindex = saddr->sll_ifindex;
                proto   = saddr->sll_protocol;
                addr    = saddr->sll_addr;
        }


        dev = dev_get_by_index(ifindex);
        err = -ENXIO;
        if (dev == NULL)
                goto out_unlock;
        if (sock->type == SOCK_RAW)
                reserve = dev->hard_header_len;

        err = -EMSGSIZE;
        if (len > dev->mtu+reserve)
                goto out_unlock;

        skb = sock_alloc_send_skb(sk, len+dev->hard_header_len+15, 0, 
                                msg->msg_flags & MSG_DONTWAIT, &err);
        if (skb==NULL)
                goto out_unlock;

        skb_reserve(skb, (dev->hard_header_len+15)&~15);
        skb->nh.raw = skb->data;

        if (dev->hard_header) {
                int res;
                err = -EINVAL;
                res = dev->hard_header(skb, dev, ntohs(proto), addr, NULL, len);
                if (sock->type != SOCK_DGRAM) {
                        skb->tail = skb->data;
                        skb->len = 0;
                } else if (res < 0)
                        goto out_free;
        }

        /* Returns -EFAULT on error */
        err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
        if (err)
                goto out_free;

        skb->protocol = proto;
        skb->dev = dev;
        skb->priority = sk->priority;

        err = -ENETDOWN;
        if (!(dev->flags & IFF_UP))
                goto out_free;

        /*
         *      Now send it
         */

        err = dev_queue_xmit(skb);
        if (err > 0 && (err = net_xmit_errno(err)) != 0)
                goto out_unlock;

        dev_put(dev);

        return(len);

out_free:
        kfree_skb(skb);
out_unlock:
        if (dev)
                dev_put(dev);
out:
        return err;
}

/*
 *      Close a PACKET socket. This is fairly simple. We immediately go
 *      to 'closed' state and remove our protocol entry in the device list.
 */

static int packet_release(struct socket *sock)
{
        struct sock *sk = sock->sk;
        struct sock **skp;

        if (!sk)
                return 0;

        write_lock_bh(&packet_sklist_lock);
        for (skp = &packet_sklist; *skp; skp = &(*skp)->next) {
                if (*skp == sk) {
                        *skp = sk->next;
                        __sock_put(sk);
                        break;
                }
        }
        write_unlock_bh(&packet_sklist_lock);

        /*
         *      Unhook packet receive handler.
         */

        if (sk->protinfo.af_packet->running) {
                /*
                 *      Remove the protocol hook
                 */
                dev_remove_pack(&sk->protinfo.af_packet->prot_hook);
                sk->protinfo.af_packet->running = 0;
                __sock_put(sk);
        }

#ifdef CONFIG_PACKET_MULTICAST
        packet_flush_mclist(sk);
#endif

#ifdef CONFIG_PACKET_MMAP
        if (sk->protinfo.af_packet->pg_vec) {
                struct tpacket_req req;
                memset(&req, 0, sizeof(req));
                packet_set_ring(sk, &req, 1);
        }
#endif

        /*
         *      Now the socket is dead. No more input will appear.
         */

        sock_orphan(sk);
        sock->sk = NULL;

        /* Purge queues */

        skb_queue_purge(&sk->receive_queue);

        sock_put(sk);
        return 0;
}

/*
 *      Attach a packet hook.
 */

static int packet_do_bind(struct sock *sk, struct net_device *dev, int protocol)
{
        /*
         *      Detach an existing hook if present.
         */

        lock_sock(sk);

        spin_lock(&sk->protinfo.af_packet->bind_lock);
        if (sk->protinfo.af_packet->running) {
                dev_remove_pack(&sk->protinfo.af_packet->prot_hook);
                __sock_put(sk);
                sk->protinfo.af_packet->running = 0;
        }

        sk->num = protocol;
        sk->protinfo.af_packet->prot_hook.type = protocol;
        sk->protinfo.af_packet->prot_hook.dev = dev;

        sk->protinfo.af_packet->ifindex = dev ? dev->ifindex : 0;

        if (protocol == 0)
                goto out_unlock;

        if (dev) {
                if (dev->flags&IFF_UP) {
                        dev_add_pack(&sk->protinfo.af_packet->prot_hook);
                        sock_hold(sk);
                        sk->protinfo.af_packet->running = 1;
                } else {
                        sk->err = ENETDOWN;
                        if (!sk->dead)
                                sk->error_report(sk);
                }
        } else {
                dev_add_pack(&sk->protinfo.af_packet->prot_hook);
                sock_hold(sk);
                sk->protinfo.af_packet->running = 1;
        }

out_unlock:
        spin_unlock(&sk->protinfo.af_packet->bind_lock);
        release_sock(sk);
        return 0;
}

/*
 *      Bind a packet socket to a device
 */

#ifdef CONFIG_SOCK_PACKET

static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
        struct sock *sk=sock->sk;
        char name[15];
        struct net_device *dev;
        int err = -ENODEV;
        
        /*
         *      Check legality
         */
         
        if(addr_len!=sizeof(struct sockaddr))
                return -EINVAL;
        strncpy(name,uaddr->sa_data,14);
        name[14]=0;

        dev = dev_get_by_name(name);
        if (dev) {
                err = packet_do_bind(sk, dev, sk->num);
                dev_put(dev);
        }
        return err;
}
#endif

static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
        struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
        struct sock *sk=sock->sk;
        struct net_device *dev = NULL;
        int err;


        /*
         *      Check legality
         */
         
        if (addr_len < sizeof(struct sockaddr_ll))
                return -EINVAL;
        if (sll->sll_family != AF_PACKET)
                return -EINVAL;

        if (sll->sll_ifindex) {
                err = -ENODEV;
                dev = dev_get_by_index(sll->sll_ifindex);
                if (dev == NULL)
                        goto out;
        }
        err = packet_do_bind(sk, dev, sll->sll_protocol ? : sk->num);
        if (dev)
                dev_put(dev);

out:
        return err;
}


/*
 *      Create a packet of type SOCK_PACKET. 
 */

static int packet_create(struct socket *sock, int protocol)
{
        struct sock *sk;
        int err;

        if (!capable(CAP_NET_RAW))
                return -EPERM;
        if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW
#ifdef CONFIG_SOCK_PACKET
            && sock->type != SOCK_PACKET
#endif
            )
                return -ESOCKTNOSUPPORT;

        sock->state = SS_UNCONNECTED;
        MOD_INC_USE_COUNT;

        err = -ENOBUFS;
        sk = sk_alloc(PF_PACKET, GFP_KERNEL, 1);
        if (sk == NULL)
                goto out;

        sock->ops = &packet_ops;
#ifdef CONFIG_SOCK_PACKET
        if (sock->type == SOCK_PACKET)
                sock->ops = &packet_ops_spkt;
#endif
        sock_init_data(sock,sk);

        sk->protinfo.af_packet = kmalloc(sizeof(struct packet_opt), GFP_KERNEL);
        if (sk->protinfo.af_packet == NULL)
                goto out_free;
        memset(sk->protinfo.af_packet, 0, sizeof(struct packet_opt));
        sk->family = PF_PACKET;
        sk->num = protocol;

        sk->destruct = packet_sock_destruct;
        atomic_inc(&packet_socks_nr);

        /*
         *      Attach a protocol block
         */

        spin_lock_init(&sk->protinfo.af_packet->bind_lock);
        sk->protinfo.af_packet->prot_hook.func = packet_rcv;
#ifdef CONFIG_SOCK_PACKET
        if (sock->type == SOCK_PACKET)
                sk->protinfo.af_packet->prot_hook.func = packet_rcv_spkt;
#endif
        sk->protinfo.af_packet->prot_hook.data = (void *)sk;

        if (protocol) {
                sk->protinfo.af_packet->prot_hook.type = protocol;
                dev_add_pack(&sk->protinfo.af_packet->prot_hook);
                sock_hold(sk);
                sk->protinfo.af_packet->running = 1;
        }

        write_lock_bh(&packet_sklist_lock);
        sk->next = packet_sklist;
        packet_sklist = sk;
        sock_hold(sk);
        write_unlock_bh(&packet_sklist_lock);
        return(0);

out_free:
        sk_free(sk);
out:
        MOD_DEC_USE_COUNT;
        return err;
}

/*
 *      Pull a packet from our receive queue and hand it to the user.
 *      If necessary we block.
 */

static int packet_recvmsg(struct socket *sock, struct msghdr *msg, int len,
                          int flags, struct scm_cookie *scm)
{
        struct sock *sk = sock->sk;
        struct sk_buff *skb;
        int copied, err;

        err = -EINVAL;
        if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC))
                goto out;

#if 0
        /* What error should we return now? EUNATTACH? */
        if (sk->protinfo.af_packet->ifindex < 0)
                return -ENODEV;
#endif

        /*
         *      If the address length field is there to be filled in, we fill
         *      it in now.
         */

        if (sock->type == SOCK_PACKET)
                msg->msg_namelen = sizeof(struct sockaddr_pkt);
        else
                msg->msg_namelen = sizeof(struct sockaddr_ll);

        /*
         *      Call the generic datagram receiver. This handles all sorts
         *      of horrible races and re-entrancy so we can forget about it
         *      in the protocol layers.
         *
         *      Now it will return ENETDOWN, if device have just gone down,
         *      but then it will block.
         */

        skb=skb_recv_datagram(sk,flags,flags&MSG_DONTWAIT,&err);

        /*
         *      An error occurred so return it. Because skb_recv_datagram() 
         *      handles the blocking we don't see and worry about blocking
         *      retries.
         */

        if(skb==NULL)
                goto out;

        /*
         *      You lose any data beyond the buffer you gave. If it worries a
         *      user program they can ask the device for its MTU anyway.
         */

        copied = skb->len;
        if (copied > len)
        {
                copied=len;
                msg->msg_flags|=MSG_TRUNC;
        }

        /* We can't use skb_copy_datagram here */
        err = memcpy_toiovec(msg->msg_iov, skb->data, copied);
        if (err)
                goto out_free;
        sk->stamp=skb->stamp;

        if (msg->msg_name)
                memcpy(msg->msg_name, skb->cb, msg->msg_namelen);

        /*
         *      Free or return the buffer as appropriate. Again this
         *      hides all the races and re-entrancy issues from us.
         */
        err = (flags&MSG_TRUNC) ? skb->len : copied;

out_free:
        skb_free_datagram(sk, skb);
out:
        return err;
}

#ifdef CONFIG_SOCK_PACKET
static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
                               int *uaddr_len, int peer)
{
        struct net_device *dev;
        struct sock *sk = sock->sk;

        if (peer)
                return -EOPNOTSUPP;

        uaddr->sa_family = AF_PACKET;
        dev = dev_get_by_index(sk->protinfo.af_packet->ifindex);
        if (dev) {
                strncpy(uaddr->sa_data, dev->name, 15);
                dev_put(dev);
        } else
                memset(uaddr->sa_data, 0, 14);
        *uaddr_len = sizeof(*uaddr);

        return 0;
}
#endif

static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
                          int *uaddr_len, int peer)
{
        struct net_device *dev;
        struct sock *sk = sock->sk;
        struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;

        if (peer)
                return -EOPNOTSUPP;

        sll->sll_family = AF_PACKET;
        sll->sll_ifindex = sk->protinfo.af_packet->ifindex;
        sll->sll_protocol = sk->num;
        dev = dev_get_by_index(sk->protinfo.af_packet->ifindex);
        if (dev) {
                sll->sll_hatype = dev->type;
                sll->sll_halen = dev->addr_len;
                memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
                dev_put(dev);
        } else {
                sll->sll_hatype = 0;    /* Bad: we have no ARPHRD_UNSPEC */
                sll->sll_halen = 0;
        }
        *uaddr_len = sizeof(*sll);

        return 0;
}

#ifdef CONFIG_PACKET_MULTICAST
static void packet_dev_mc(struct net_device *dev, struct packet_mclist *i, int what)
{
        switch (i->type) {
        case PACKET_MR_MULTICAST:
                if (what > 0)
                        dev_mc_add(dev, i->addr, i->alen, 0);
                else
                        dev_mc_delete(dev, i->addr, i->alen, 0);
                break;
        case PACKET_MR_PROMISC:
                dev_set_promiscuity(dev, what);
                break;
        case PACKET_MR_ALLMULTI:
                dev_set_allmulti(dev, what);
                break;
        default:
        }
}

static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
{
        for ( ; i; i=i->next) {
                if (i->ifindex == dev->ifindex)
                        packet_dev_mc(dev, i, what);
        }
}

static int packet_mc_add(struct sock *sk, struct packet_mreq *mreq)
{
        struct packet_mclist *ml, *i;
        struct net_device *dev;
        int err;

        rtnl_lock();

        err = -ENODEV;
        dev = __dev_get_by_index(mreq->mr_ifindex);
        if (!dev)
                goto done;

        err = -EINVAL;
        if (mreq->mr_alen > dev->addr_len)
                goto done;

        err = -ENOBUFS;
        i = (struct packet_mclist *)kmalloc(sizeof(*i), GFP_KERNEL);
        if (i == NULL)
                goto done;

        err = 0;
        for (ml=sk->protinfo.af_packet->mclist; ml; ml=ml->next) {
                if (ml->ifindex == mreq->mr_ifindex &&
                    ml->type == mreq->mr_type &&
                    ml->alen == mreq->mr_alen &&
                    memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
                        ml->count++;
                        /* Free the new element ... */
                        kfree(i);
                        goto done;
                }
        }

        i->type = mreq->mr_type;
        i->ifindex = mreq->mr_ifindex;
        i->alen = mreq->mr_alen;
        memcpy(i->addr, mreq->mr_address, i->alen);
        i->count = 1;
        i->next = sk->protinfo.af_packet->mclist;
        sk->protinfo.af_packet->mclist = i;
        packet_dev_mc(dev, i, +1);

done:
        rtnl_unlock();
        return err;
}

static int packet_mc_drop(struct sock *sk, struct packet_mreq *mreq)
{
        struct packet_mclist *ml, **mlp;

        rtnl_lock();

        for (mlp=&sk->protinfo.af_packet->mclist; (ml=*mlp)!=NULL; mlp=&ml->next) {
                if (ml->ifindex == mreq->mr_ifindex &&
                    ml->type == mreq->mr_type &&
                    ml->alen == mreq->mr_alen &&
                    memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
                        if (--ml->count == 0) {
                                struct net_device *dev;
                                *mlp = ml->next;
                                dev = dev_get_by_index(ml->ifindex);
                                if (dev) {
                                        packet_dev_mc(dev, ml, -1);
                                        dev_put(dev);
                                }
                                kfree_s(ml, sizeof(*ml));
                        }
                        rtnl_unlock();
                        return 0;
                }
        }
        rtnl_unlock();
        return -EADDRNOTAVAIL;
}

static void packet_flush_mclist(struct sock *sk)
{
        struct packet_mclist *ml;

        if (sk->protinfo.af_packet->mclist == NULL)
                return;

        rtnl_lock();
        while ((ml=sk->protinfo.af_packet->mclist) != NULL) {
                struct net_device *dev;
                sk->protinfo.af_packet->mclist = ml->next;
                if ((dev = dev_get_by_index(ml->ifindex)) != NULL) {
                        packet_dev_mc(dev, ml, -1);
                        dev_put(dev);
                }
                kfree_s(ml, sizeof(*ml));
        }
        rtnl_unlock();
}
#endif

static int
packet_setsockopt(struct socket *sock, int level, int optname, char *optval, int optlen)
{
        struct sock *sk = sock->sk;
        int ret;

        if (level != SOL_PACKET)
                return -ENOPROTOOPT;

        switch(optname) {
#ifdef CONFIG_PACKET_MULTICAST
        case PACKET_ADD_MEMBERSHIP:     
        case PACKET_DROP_MEMBERSHIP:
        {
                struct packet_mreq mreq;
                if (optlen<sizeof(mreq))
                        return -EINVAL;
                if (copy_from_user(&mreq,optval,sizeof(mreq)))
                        return -EFAULT;
                if (optname == PACKET_ADD_MEMBERSHIP)
                        ret = packet_mc_add(sk, &mreq);
                else
                        ret = packet_mc_drop(sk, &mreq);
                return ret;
        }
#endif
#ifdef CONFIG_PACKET_MMAP
        case PACKET_RX_RING:
        {
                struct tpacket_req req;

                if (optlen<sizeof(req))
                        return -EINVAL;
                if (copy_from_user(&req,optval,sizeof(req)))
                        return -EFAULT;
                return packet_set_ring(sk, &req, 0);
        }
#endif
        default:
                return -ENOPROTOOPT;
        }
}

int packet_getsockopt(struct socket *sock, int level, int optname,
                      char *optval, int *optlen)
{
        int len;
        struct sock *sk = sock->sk;

        if (level != SOL_PACKET)
                return -ENOPROTOOPT;

        if (get_user(len,optlen))
                return -EFAULT;

        switch(optname) {
        case PACKET_STATISTICS:
        {
                struct tpacket_stats st;

                if (len > sizeof(struct tpacket_stats))
                        len = sizeof(struct tpacket_stats);
                spin_lock_bh(&sk->receive_queue.lock);
                st = sk->protinfo.af_packet->stats;
                memset(&sk->protinfo.af_packet->stats, 0, sizeof(st));
                spin_unlock_bh(&sk->receive_queue.lock);
                st.tp_packets += st.tp_drops;

                if (copy_to_user(optval, &st, len))
                        return -EFAULT;
                break;
        }
        default:
                return -ENOPROTOOPT;
        }

        if (put_user(len, optlen))
                return -EFAULT;
        return 0;
}


static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
{
        struct sock *sk;
        struct packet_opt *po;
        struct net_device *dev = (struct net_device*)data;

        read_lock(&packet_sklist_lock);
        for (sk = packet_sklist; sk; sk = sk->next) {
                po = sk->protinfo.af_packet;

                switch (msg) {
                case NETDEV_DOWN:
                case NETDEV_UNREGISTER:
                        if (dev->ifindex == po->ifindex) {
                                spin_lock(&po->bind_lock);
                                if (po->running) {
                                        dev_remove_pack(&po->prot_hook);
                                        __sock_put(sk);
                                        po->running = 0;
                                        sk->err = ENETDOWN;
                                        if (!sk->dead)
                                                sk->error_report(sk);
                                }
                                if (msg == NETDEV_UNREGISTER) {
                                        po->ifindex = -1;
                                        po->prot_hook.dev = NULL;
                                }
                                spin_unlock(&po->bind_lock);
                        }
#ifdef CONFIG_PACKET_MULTICAST
                        if (po->mclist)
                                packet_dev_mclist(dev, po->mclist, -1);
#endif
                        break;
                case NETDEV_UP:
                        spin_lock(&po->bind_lock);
                        if (dev->ifindex == po->ifindex && sk->num && po->running==0) {
                                dev_add_pack(&po->prot_hook);
                                sock_hold(sk);
                                po->running = 1;
                        }
                        spin_unlock(&po->bind_lock);
#ifdef CONFIG_PACKET_MULTICAST
                        if (po->mclist)
                                packet_dev_mclist(dev, po->mclist, +1);
#endif
                        break;
                }
        }
        read_unlock(&packet_sklist_lock);
        return NOTIFY_DONE;
}


static int packet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
        struct sock *sk = sock->sk;
        int err;
        int pid;

        switch(cmd) 
        {
                case FIOSETOWN:
                case SIOCSPGRP:
                        err = get_user(pid, (int *) arg);
                        if (err)
                                return err; 
                        if (current->pid != pid && current->pgrp != -pid && 
                            !capable(CAP_NET_ADMIN))
                                return -EPERM;
                        sk->proc = pid;
                        return(0);
                case FIOGETOWN:
                case SIOCGPGRP:
                        return put_user(sk->proc, (int *)arg);
                case SIOCGSTAMP:
                        if(sk->stamp.tv_sec==0)
                                return -ENOENT;
                        err = -EFAULT;
                        if (!copy_to_user((void *)arg, &sk->stamp, sizeof(struct timeval)))
                                err = 0;
                        return err;
                case SIOCGIFFLAGS:
#ifndef CONFIG_INET
                case SIOCSIFFLAGS:
#endif
                case SIOCGIFCONF:
                case SIOCGIFMETRIC:
                case SIOCSIFMETRIC:
                case SIOCGIFMEM:
                case SIOCSIFMEM:
                case SIOCGIFMTU:
                case SIOCSIFMTU:
                case SIOCSIFLINK:
                case SIOCGIFHWADDR:
                case SIOCSIFHWADDR:
                case SIOCSIFMAP:
                case SIOCGIFMAP:
                case SIOCSIFSLAVE:
                case SIOCGIFSLAVE:
                case SIOCGIFINDEX:
                case SIOCGIFNAME:
                case SIOCGIFCOUNT:
                case SIOCSIFHWBROADCAST:
                        return(dev_ioctl(cmd,(void *) arg));

                case SIOCGIFBR:
                case SIOCSIFBR:
#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
#ifdef CONFIG_INET
#ifdef CONFIG_KMOD
                        if (br_ioctl_hook == NULL)
                                request_module("bridge");
#endif
                        if (br_ioctl_hook != NULL)
                                return br_ioctl_hook(arg);
#endif
#endif                          

                        return -ENOPKG;
                        
#ifdef CONFIG_INET
                case SIOCADDRT:
                case SIOCDELRT:
                case SIOCDARP:
                case SIOCGARP:
                case SIOCSARP:
                case SIOCGIFADDR:
                case SIOCSIFADDR:
                case SIOCGIFBRDADDR:
                case SIOCSIFBRDADDR:
                case SIOCGIFNETMASK:
                case SIOCSIFNETMASK:
                case SIOCGIFDSTADDR:
                case SIOCSIFDSTADDR:
                case SIOCSIFFLAGS:
                case SIOCADDDLCI:
                case SIOCDELDLCI:
                        return inet_dgram_ops.ioctl(sock, cmd, arg);
#endif

                default:
                        if ((cmd >= SIOCDEVPRIVATE) &&
                            (cmd <= (SIOCDEVPRIVATE + 15)))
                                return(dev_ioctl(cmd,(void *) arg));

#ifdef CONFIG_NET_RADIO
                        if((cmd >= SIOCIWFIRST) && (cmd <= SIOCIWLAST))
                                return(dev_ioctl(cmd,(void *) arg));
#endif
                        return -EOPNOTSUPP;
        }
        /*NOTREACHED*/
        return(0);
}

#ifndef CONFIG_PACKET_MMAP
#define packet_mmap sock_no_mmap
#define packet_poll datagram_poll
#else

unsigned int packet_poll(struct file * file, struct socket *sock, poll_table *wait)
{
        struct sock *sk = sock->sk;
        struct packet_opt *po = sk->protinfo.af_packet;
        unsigned int mask = datagram_poll(file, sock, wait);

        spin_lock_bh(&sk->receive_queue.lock);
        if (po->iovec) {
                unsigned last = po->head ? po->head-1 : po->iovmax;

                if (po->iovec[last]->tp_status)
                        mask |= POLLIN | POLLRDNORM;
        }
        spin_unlock_bh(&sk->receive_queue.lock);
        return mask;
}


/* Dirty? Well, I still did not learn better way to account
 * for user mmaps.
 */

static void packet_mm_open(struct vm_area_struct *vma)
{
        struct file *file = vma->vm_file;
        struct inode *inode = file->f_dentry->d_inode;
        struct socket * sock = &inode->u.socket_i;
        struct sock *sk = sock->sk;
        
        if (sk)
                atomic_inc(&sk->protinfo.af_packet->mapped);
}

static void packet_mm_close(struct vm_area_struct *vma)
{
        struct file *file = vma->vm_file;
        struct inode *inode = file->f_dentry->d_inode;
        struct socket * sock = &inode->u.socket_i;
        struct sock *sk = sock->sk;
        
        if (sk)
                atomic_dec(&sk->protinfo.af_packet->mapped);
}

static struct vm_operations_struct packet_mmap_ops = {
        open:   packet_mm_open,
        close:  packet_mm_close,
};

static void free_pg_vec(unsigned long *pg_vec, unsigned order, unsigned len)
{
        int i;

        for (i=0; i<len; i++) {
                if (pg_vec[i]) {
                        unsigned long map, mapend;

                        mapend = MAP_NR(pg_vec[i] + (PAGE_SIZE << order) - 1);
                        for (map = MAP_NR(pg_vec[i]); map <= mapend; map++)
                                clear_bit(PG_reserved, &mem_map[map].flags);
                        free_pages(pg_vec[i], order);
                }
        }
        kfree(pg_vec);
}


static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing)
{
        unsigned long *pg_vec = NULL;
        struct tpacket_hdr **io_vec = NULL;
        struct packet_opt *po = sk->protinfo.af_packet;
        int order = 0;
        int err = 0;

        if (req->tp_block_nr) {
                int i, l;
                int frames_per_block;

                /* Sanity tests and some calculations */
                if ((int)req->tp_block_size <= 0)
                        return -EINVAL;
                if (req->tp_block_size&(PAGE_SIZE-1))
                        return -EINVAL;
                if (req->tp_frame_size < TPACKET_HDRLEN)
                        return -EINVAL;
                if (req->tp_frame_size&(TPACKET_ALIGNMENT-1))
                        return -EINVAL;
                frames_per_block = req->tp_block_size/req->tp_frame_size;
                if (frames_per_block <= 0)
                        return -EINVAL;
                if (frames_per_block*req->tp_block_nr != req->tp_frame_nr)
                        return -EINVAL;
                /* OK! */

                /* Allocate page vector */
                while ((PAGE_SIZE<<order) < req->tp_block_size)
                        order++;

                err = -ENOMEM;

                pg_vec = kmalloc(req->tp_block_nr*sizeof(unsigned long*), GFP_KERNEL);
                if (pg_vec == NULL)
                        goto out;
                memset(pg_vec, 0, req->tp_block_nr*sizeof(unsigned long*));

                for (i=0; i<req->tp_block_nr; i++) {
                        unsigned long map, mapend;
                        pg_vec[i] = __get_free_pages(GFP_KERNEL, order);
                        if (!pg_vec[i])
                                goto out_free_pgvec;

                        mapend = MAP_NR(pg_vec[i] + (PAGE_SIZE << order) - 1);
                        for (map = MAP_NR(pg_vec[i]); map <= mapend; map++)
                                set_bit(PG_reserved, &mem_map[map].flags);
                }
                /* Page vector is allocated */

                /* Draw frames */
                io_vec = kmalloc(req->tp_frame_nr*sizeof(struct tpacket_hdr*), GFP_KERNEL);
                if (io_vec == NULL)
                        goto out_free_pgvec;
                memset(io_vec, 0, req->tp_frame_nr*sizeof(struct tpacket_hdr*));

                l = 0;
                for (i=0; i<req->tp_block_nr; i++) {
                        unsigned long ptr = pg_vec[i];
                        int k;

                        for (k=0; k<frames_per_block; k++, l++) {
                                io_vec[l] = (struct tpacket_hdr*)ptr;
                                io_vec[l]->tp_status = TP_STATUS_KERNEL;
                                ptr += req->tp_frame_size;
                        }
                }
                /* Done */
        } else {
                if (req->tp_frame_nr)
                        return -EINVAL;
        }

        lock_sock(sk);

        /* Detach socket from network */
        spin_lock(&po->bind_lock);
        if (po->running)
                dev_remove_pack(&po->prot_hook);
        spin_unlock(&po->bind_lock);

        err = -EBUSY;
        if (closing || atomic_read(&po->mapped) == 0) {
                err = 0;
#define XC(a, b) ({ __typeof__ ((a)) __t; __t = (a); (a) = (b); __t; })

                spin_lock_bh(&sk->receive_queue.lock);
                pg_vec = XC(po->pg_vec, pg_vec);
                io_vec = XC(po->iovec, io_vec);
                po->iovmax = req->tp_frame_nr-1;
                po->head = 0;
                po->frame_size = req->tp_frame_size;
                spin_unlock_bh(&sk->receive_queue.lock);

                order = XC(po->pg_vec_order, order);
                req->tp_block_nr = XC(po->pg_vec_len, req->tp_block_nr);

                po->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
                po->prot_hook.func = po->iovec ? tpacket_rcv : packet_rcv;
                skb_queue_purge(&sk->receive_queue);
#undef XC
                if (atomic_read(&po->mapped))
                        printk(KERN_DEBUG "packet_mmap: vma is busy: %d\n", atomic_read(&po->mapped));
        }

        spin_lock(&po->bind_lock);
        if (po->running)
                dev_add_pack(&po->prot_hook);
        spin_unlock(&po->bind_lock);

        release_sock(sk);

        if (io_vec)
                kfree(io_vec);

out_free_pgvec:
        if (pg_vec)
                free_pg_vec(pg_vec, order, req->tp_block_nr);
out:
        return err;
}

static int packet_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
{
        struct sock *sk = sock->sk;
        struct packet_opt *po = sk->protinfo.af_packet;
        unsigned long size;
        unsigned long start;
        int err = -EINVAL;
        int i;

        if (vma->vm_pgoff)
                return -EINVAL;

        size = vma->vm_end - vma->vm_start;

        lock_sock(sk);
        if (po->pg_vec == NULL)
                goto out;
        if (size != po->pg_vec_len*po->pg_vec_pages*PAGE_SIZE)
                goto out;

        atomic_inc(&po->mapped);
        start = vma->vm_start;
        err = -EAGAIN;
        for (i=0; i<po->pg_vec_len; i++) {
                if (remap_page_range(start, __pa(po->pg_vec[i]),
                                     po->pg_vec_pages*PAGE_SIZE,
                                     vma->vm_page_prot))
                        goto out;
                start += po->pg_vec_pages*PAGE_SIZE;
        }
        vma->vm_ops = &packet_mmap_ops;
        err = 0;

out:
        release_sock(sk);
        return err;
}
#endif


#ifdef CONFIG_SOCK_PACKET
struct proto_ops packet_ops_spkt = {
        PF_PACKET,

        packet_release,
        packet_bind_spkt,
        sock_no_connect,
        sock_no_socketpair,
        sock_no_accept,
        packet_getname_spkt,
        datagram_poll,
        packet_ioctl,
        sock_no_listen,
        sock_no_shutdown,
        sock_no_setsockopt,
        sock_no_getsockopt,
        sock_no_fcntl,
        packet_sendmsg_spkt,
        packet_recvmsg,
        sock_no_mmap
};
#endif

struct proto_ops packet_ops = {
        PF_PACKET,

        packet_release,
        packet_bind,
        sock_no_connect,
        sock_no_socketpair,
        sock_no_accept,
        packet_getname, 
        packet_poll,
        packet_ioctl,
        sock_no_listen,
        sock_no_shutdown,
        packet_setsockopt,
        packet_getsockopt,
        sock_no_fcntl,
        packet_sendmsg,
        packet_recvmsg,
        packet_mmap,
};

static struct net_proto_family packet_family_ops = {
        PF_PACKET,
        packet_create
};

struct notifier_block packet_netdev_notifier={
        packet_notifier,
        NULL,
        0
};

#ifdef CONFIG_PROC_FS
static int packet_read_proc(char *buffer, char **start, off_t offset,
                             int length, int *eof, void *data)
{
        off_t pos=0;
        off_t begin=0;
        int len=0;
        struct sock *s;
        
        len+= sprintf(buffer,"sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");

        read_lock(&packet_sklist_lock);

        for (s = packet_sklist; s; s = s->next) {
                len+=sprintf(buffer+len,"%p %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu",
                             s,
                             atomic_read(&s->refcnt),
                             s->type,
                             ntohs(s->num),
                             s->protinfo.af_packet->ifindex,
                             s->protinfo.af_packet->running,
                             atomic_read(&s->rmem_alloc),
                             s->socket->inode->i_uid,
                             s->socket->inode->i_ino
                             );

                buffer[len++]='\n';
                
                pos=begin+len;
                if(pos<offset) {
                        len=0;
                        begin=pos;
                }
                if(pos>offset+length)
                        goto done;
        }
        *eof = 1;

done:
        read_unlock(&packet_sklist_lock);
        *start=buffer+(offset-begin);
        len-=(offset-begin);
        if(len>length)
                len=length;
        if(len<0)
                len=0;
        return len;
}
#endif


#ifdef MODULE
void cleanup_module(void)
{
#ifdef CONFIG_PROC_FS
        remove_proc_entry("net/packet", 0);
#endif
        unregister_netdevice_notifier(&packet_netdev_notifier);
        sock_unregister(PF_PACKET);
        return;
}


int init_module(void)
#else
void __init packet_proto_init(struct net_proto *pro)
#endif
{
        sock_register(&packet_family_ops);
        register_netdevice_notifier(&packet_netdev_notifier);
#ifdef CONFIG_PROC_FS
        create_proc_read_entry("net/packet", 0, 0, packet_read_proc, NULL);
#endif
#ifdef MODULE
        return 0;
#endif
}