1 files changed, 1153 insertions, 0 deletions

diff --git a/drivers/net/pppoe.c b/drivers/net/pppoe.c
new file mode 100644
index 000000000000..ce1a9bf7b9a7
--- /dev/null
+++ b/drivers/net/pppoe.c
@@ -0,0 +1,1153 @@
+/** -*- linux-c -*- ***********************************************************
+ * Linux PPP over Ethernet (PPPoX/PPPoE) Sockets
+ *
+ * PPPoX --- Generic PPP encapsulation socket family
+ * PPPoE --- PPP over Ethernet (RFC 2516)
+ *
+ *
+ * Version:	0.7.0
+ *
+ * 220102 :	Fix module use count on failure in pppoe_create, pppox_sk -acme
+ * 030700 :	Fixed connect logic to allow for disconnect.
+ * 270700 :	Fixed potential SMP problems; we must protect against
+ *		simultaneous invocation of ppp_input
+ *		and ppp_unregister_channel.
+ * 040800 :	Respect reference count mechanisms on net-devices.
+ * 200800 :	fix kfree(skb) in pppoe_rcv (acme)
+ *		Module reference count is decremented in the right spot now,
+ *		guards against sock_put not actually freeing the sk
+ *		in pppoe_release.
+ * 051000 :	Initialization cleanup.
+ * 111100 :	Fix recvmsg.
+ * 050101 :	Fix PADT procesing.
+ * 140501 :	Use pppoe_rcv_core to handle all backlog. (Alexey)
+ * 170701 :	Do not lock_sock with rwlock held. (DaveM)
+ *		Ignore discovery frames if user has socket
+ *		locked. (DaveM)
+ *		Ignore return value of dev_queue_xmit in __pppoe_xmit
+ *		or else we may kfree an SKB twice. (DaveM)
+ * 190701 :	When doing copies of skb's in __pppoe_xmit, always delete
+ *		the original skb that was passed in on success, never on
+ *		failure.  Delete the copy of the skb on failure to avoid
+ *		a memory leak.
+ * 081001 :	Misc. cleanup (licence string, non-blocking, prevent
+ *		reference of device on close).
+ * 121301 :	New ppp channels interface; cannot unregister a channel
+ *		from interrupts.  Thus, we mark the socket as a ZOMBIE
+ *		and do the unregistration later.
+ * 081002 :	seq_file support for proc stuff -acme
+ * 111602 :	Merge all 2.4 fixes into 2.5/2.6 tree.  Label 2.5/2.6
+ *		as version 0.7.  Spacing cleanup.
+ * Author:	Michal Ostrowski <mostrows@speakeasy.net>
+ * Contributors:
+ * 		Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *		David S. Miller (davem@redhat.com)
+ *
+ * License:
+ *		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/string.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <linux/net.h>
+#include <linux/inetdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/init.h>
+#include <linux/if_ether.h>
+#include <linux/if_pppox.h>
+#include <linux/ppp_channel.h>
+#include <linux/ppp_defs.h>
+#include <linux/if_ppp.h>
+#include <linux/notifier.h>
+#include <linux/file.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+#include <net/sock.h>
+
+#include <asm/uaccess.h>
+
+#define PPPOE_HASH_BITS 4
+#define PPPOE_HASH_SIZE (1<<PPPOE_HASH_BITS)
+
+static struct ppp_channel_ops pppoe_chan_ops;
+
+static int pppoe_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
+static int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb);
+static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb);
+
+static struct proto_ops pppoe_ops;
+static DEFINE_RWLOCK(pppoe_hash_lock);
+
+static struct ppp_channel_ops pppoe_chan_ops;
+
+static inline int cmp_2_addr(struct pppoe_addr *a, struct pppoe_addr *b)
+{
+	return (a->sid == b->sid &&
+		(memcmp(a->remote, b->remote, ETH_ALEN) == 0));
+}
+
+static inline int cmp_addr(struct pppoe_addr *a, unsigned long sid, char *addr)
+{
+	return (a->sid == sid &&
+		(memcmp(a->remote,addr,ETH_ALEN) == 0));
+}
+
+static int hash_item(unsigned long sid, unsigned char *addr)
+{
+	char hash = 0;
+	int i, j;
+
+	for (i = 0; i < ETH_ALEN ; ++i) {
+		for (j = 0; j < 8/PPPOE_HASH_BITS ; ++j) {
+			hash ^= addr[i] >> ( j * PPPOE_HASH_BITS );
+		}
+	}
+
+	for (i = 0; i < (sizeof(unsigned long)*8) / PPPOE_HASH_BITS ; ++i)
+		hash ^= sid >> (i*PPPOE_HASH_BITS);
+
+	return hash & ( PPPOE_HASH_SIZE - 1 );
+}
+
+/* zeroed because its in .bss */
+static struct pppox_sock *item_hash_table[PPPOE_HASH_SIZE];
+
+/**********************************************************************
+ *
+ *  Set/get/delete/rehash items  (internal versions)
+ *
+ **********************************************************************/
+static struct pppox_sock *__get_item(unsigned long sid, unsigned char *addr)
+{
+	int hash = hash_item(sid, addr);
+	struct pppox_sock *ret;
+
+	ret = item_hash_table[hash];
+
+	while (ret && !cmp_addr(&ret->pppoe_pa, sid, addr))
+		ret = ret->next;
+
+	return ret;
+}
+
+static int __set_item(struct pppox_sock *po)
+{
+	int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
+	struct pppox_sock *ret;
+
+	ret = item_hash_table[hash];
+	while (ret) {
+		if (cmp_2_addr(&ret->pppoe_pa, &po->pppoe_pa))
+			return -EALREADY;
+
+		ret = ret->next;
+	}
+
+	if (!ret) {
+		po->next = item_hash_table[hash];
+		item_hash_table[hash] = po;
+	}
+
+	return 0;
+}
+
+static struct pppox_sock *__delete_item(unsigned long sid, char *addr)
+{
+	int hash = hash_item(sid, addr);
+	struct pppox_sock *ret, **src;
+
+	ret = item_hash_table[hash];
+	src = &item_hash_table[hash];
+
+	while (ret) {
+		if (cmp_addr(&ret->pppoe_pa, sid, addr)) {
+			*src = ret->next;
+			break;
+		}
+
+		src = &ret->next;
+		ret = ret->next;
+	}
+
+	return ret;
+}
+
+/**********************************************************************
+ *
+ *  Set/get/delete/rehash items
+ *
+ **********************************************************************/
+static inline struct pppox_sock *get_item(unsigned long sid,
+					 unsigned char *addr)
+{
+	struct pppox_sock *po;
+
+	read_lock_bh(&pppoe_hash_lock);
+	po = __get_item(sid, addr);
+	if (po)
+		sock_hold(sk_pppox(po));
+	read_unlock_bh(&pppoe_hash_lock);
+
+	return po;
+}
+
+static inline struct pppox_sock *get_item_by_addr(struct sockaddr_pppox *sp)
+{
+	return get_item(sp->sa_addr.pppoe.sid, sp->sa_addr.pppoe.remote);
+}
+
+static inline int set_item(struct pppox_sock *po)
+{
+	int i;
+
+	if (!po)
+		return -EINVAL;
+
+	write_lock_bh(&pppoe_hash_lock);
+	i = __set_item(po);
+	write_unlock_bh(&pppoe_hash_lock);
+
+	return i;
+}
+
+static inline struct pppox_sock *delete_item(unsigned long sid, char *addr)
+{
+	struct pppox_sock *ret;
+
+	write_lock_bh(&pppoe_hash_lock);
+	ret = __delete_item(sid, addr);
+	write_unlock_bh(&pppoe_hash_lock);
+
+	return ret;
+}
+
+
+
+/***************************************************************************
+ *
+ *  Handler for device events.
+ *  Certain device events require that sockets be unconnected.
+ *
+ **************************************************************************/
+
+static void pppoe_flush_dev(struct net_device *dev)
+{
+	int hash;
+
+	BUG_ON(dev == NULL);
+
+	read_lock_bh(&pppoe_hash_lock);
+	for (hash = 0; hash < PPPOE_HASH_SIZE; hash++) {
+		struct pppox_sock *po = item_hash_table[hash];
+
+		while (po != NULL) {
+			if (po->pppoe_dev == dev) {
+				struct sock *sk = sk_pppox(po);
+
+				sock_hold(sk);
+				po->pppoe_dev = NULL;
+
+				/* We hold a reference to SK, now drop the
+				 * hash table lock so that we may attempt
+				 * to lock the socket (which can sleep).
+				 */
+				read_unlock_bh(&pppoe_hash_lock);
+
+				lock_sock(sk);
+
+				if (sk->sk_state &
+				    (PPPOX_CONNECTED | PPPOX_BOUND)) {
+					pppox_unbind_sock(sk);
+					dev_put(dev);
+					sk->sk_state = PPPOX_ZOMBIE;
+					sk->sk_state_change(sk);
+				}
+
+				release_sock(sk);
+
+				sock_put(sk);
+
+				read_lock_bh(&pppoe_hash_lock);
+
+				/* Now restart from the beginning of this
+				 * hash chain.  We always NULL out pppoe_dev
+				 * so we are guaranteed to make forward
+				 * progress.
+				 */
+				po = item_hash_table[hash];
+				continue;
+			}
+			po = po->next;
+		}
+	}
+	read_unlock_bh(&pppoe_hash_lock);
+}
+
+static int pppoe_device_event(struct notifier_block *this,
+			      unsigned long event, void *ptr)
+{
+	struct net_device *dev = (struct net_device *) ptr;
+
+	/* Only look at sockets that are using this specific device. */
+	switch (event) {
+	case NETDEV_CHANGEMTU:
+		/* A change in mtu is a bad thing, requiring
+		 * LCP re-negotiation.
+		 */
+
+	case NETDEV_GOING_DOWN:
+	case NETDEV_DOWN:
+		/* Find every socket on this device and kill it. */
+		pppoe_flush_dev(dev);
+		break;
+
+	default:
+		break;
+	};
+
+	return NOTIFY_DONE;
+}
+
+
+static struct notifier_block pppoe_notifier = {
+	.notifier_call = pppoe_device_event,
+};
+
+
+/************************************************************************
+ *
+ * Do the real work of receiving a PPPoE Session frame.
+ *
+ ***********************************************************************/
+static int pppoe_rcv_core(struct sock *sk, struct sk_buff *skb)
+{
+	struct pppox_sock *po = pppox_sk(sk);
+	struct pppox_sock *relay_po = NULL;
+
+	if (sk->sk_state & PPPOX_BOUND) {
+		struct pppoe_hdr *ph = (struct pppoe_hdr *) skb->nh.raw;
+		int len = ntohs(ph->length);
+		skb_pull(skb, sizeof(struct pppoe_hdr));
+		skb_postpull_rcsum(skb, ph, sizeof(*ph));
+		if (pskb_trim_rcsum(skb, len))
+			goto abort_kfree;
+
+		ppp_input(&po->chan, skb);
+	} else if (sk->sk_state & PPPOX_RELAY) {
+		relay_po = get_item_by_addr(&po->pppoe_relay);
+
+		if (relay_po == NULL)
+			goto abort_kfree;
+
+		if ((sk_pppox(relay_po)->sk_state & PPPOX_CONNECTED) == 0)
+			goto abort_put;
+
+		skb_pull(skb, sizeof(struct pppoe_hdr));
+		if (!__pppoe_xmit(sk_pppox(relay_po), skb))
+			goto abort_put;
+	} else {
+		if (sock_queue_rcv_skb(sk, skb))
+			goto abort_kfree;
+	}
+
+	return NET_RX_SUCCESS;
+
+abort_put:
+	sock_put(sk_pppox(relay_po));
+
+abort_kfree:
+	kfree_skb(skb);
+	return NET_RX_DROP;
+}
+
+/************************************************************************
+ *
+ * Receive wrapper called in BH context.
+ *
+ ***********************************************************************/
+static int pppoe_rcv(struct sk_buff *skb,
+		     struct net_device *dev,
+		     struct packet_type *pt)
+
+{
+	struct pppoe_hdr *ph;
+	struct pppox_sock *po;
+	struct sock *sk;
+	int ret;
+
+	if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
+		goto drop;
+
+	if (!(skb = skb_share_check(skb, GFP_ATOMIC))) 
+		goto out;
+
+	ph = (struct pppoe_hdr *) skb->nh.raw;
+
+	po = get_item((unsigned long) ph->sid, eth_hdr(skb)->h_source);
+	if (!po) 
+		goto drop;
+
+	sk = sk_pppox(po);
+	bh_lock_sock(sk);
+
+	/* Socket state is unknown, must put skb into backlog. */
+	if (sock_owned_by_user(sk) != 0) {
+		sk_add_backlog(sk, skb);
+		ret = NET_RX_SUCCESS;
+	} else {
+		ret = pppoe_rcv_core(sk, skb);
+	}
+
+	bh_unlock_sock(sk);
+	sock_put(sk);
+
+	return ret;
+drop:
+	kfree_skb(skb);
+out:
+	return NET_RX_DROP;
+}
+
+/************************************************************************
+ *
+ * Receive a PPPoE Discovery frame.
+ * This is solely for detection of PADT frames
+ *
+ ***********************************************************************/
+static int pppoe_disc_rcv(struct sk_buff *skb,
+			  struct net_device *dev,
+			  struct packet_type *pt)
+
+{
+	struct pppoe_hdr *ph;
+	struct pppox_sock *po;
+
+	if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
+		goto abort;
+
+	if (!(skb = skb_share_check(skb, GFP_ATOMIC))) 
+		goto out;
+
+	ph = (struct pppoe_hdr *) skb->nh.raw;
+	if (ph->code != PADT_CODE)
+		goto abort;
+
+	po = get_item((unsigned long) ph->sid, eth_hdr(skb)->h_source);
+	if (po) {
+		struct sock *sk = sk_pppox(po);
+
+		bh_lock_sock(sk);
+
+		/* If the user has locked the socket, just ignore
+		 * the packet.  With the way two rcv protocols hook into
+		 * one socket family type, we cannot (easily) distinguish
+		 * what kind of SKB it is during backlog rcv.
+		 */
+		if (sock_owned_by_user(sk) == 0) {
+			/* We're no longer connect at the PPPOE layer,
+			 * and must wait for ppp channel to disconnect us.
+			 */
+			sk->sk_state = PPPOX_ZOMBIE;
+		}
+
+		bh_unlock_sock(sk);
+		sock_put(sk);
+	}
+
+abort:
+	kfree_skb(skb);
+out:
+	return NET_RX_SUCCESS; /* Lies... :-) */
+}
+
+static struct packet_type pppoes_ptype = {
+	.type	= __constant_htons(ETH_P_PPP_SES),
+	.func	= pppoe_rcv,
+};
+
+static struct packet_type pppoed_ptype = {
+	.type	= __constant_htons(ETH_P_PPP_DISC),
+	.func	= pppoe_disc_rcv,
+};
+
+static struct proto pppoe_sk_proto = {
+	.name	  = "PPPOE",
+	.owner	  = THIS_MODULE,
+	.obj_size = sizeof(struct pppox_sock),
+};
+
+/***********************************************************************
+ *
+ * Initialize a new struct sock.
+ *
+ **********************************************************************/
+static int pppoe_create(struct socket *sock)
+{
+	int error = -ENOMEM;
+	struct sock *sk;
+
+	sk = sk_alloc(PF_PPPOX, GFP_KERNEL, &pppoe_sk_proto, 1);
+	if (!sk)
+		goto out;
+
+	sock_init_data(sock, sk);
+
+	sock->state = SS_UNCONNECTED;
+	sock->ops   = &pppoe_ops;
+
+	sk->sk_backlog_rcv = pppoe_rcv_core;
+	sk->sk_state	   = PPPOX_NONE;
+	sk->sk_type	   = SOCK_STREAM;
+	sk->sk_family	   = PF_PPPOX;
+	sk->sk_protocol	   = PX_PROTO_OE;
+
+	error = 0;
+out:	return error;
+}
+
+static int pppoe_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct pppox_sock *po;
+	int error = 0;
+
+	if (!sk)
+		return 0;
+
+	if (sock_flag(sk, SOCK_DEAD))
+		return -EBADF;
+
+	pppox_unbind_sock(sk);
+
+	/* Signal the death of the socket. */
+	sk->sk_state = PPPOX_DEAD;
+
+	po = pppox_sk(sk);
+	if (po->pppoe_pa.sid) {
+		delete_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
+	}
+
+	if (po->pppoe_dev)
+		dev_put(po->pppoe_dev);
+
+	po->pppoe_dev = NULL;
+
+	sock_orphan(sk);
+	sock->sk = NULL;
+
+	skb_queue_purge(&sk->sk_receive_queue);
+	sock_put(sk);
+
+	return error;
+}
+
+
+static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
+		  int sockaddr_len, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct net_device *dev = NULL;
+	struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
+	struct pppox_sock *po = pppox_sk(sk);
+	int error;
+
+	lock_sock(sk);
+
+	error = -EINVAL;
+	if (sp->sa_protocol != PX_PROTO_OE)
+		goto end;
+
+	/* Check for already bound sockets */
+	error = -EBUSY;
+	if ((sk->sk_state & PPPOX_CONNECTED) && sp->sa_addr.pppoe.sid)
+		goto end;
+
+	/* Check for already disconnected sockets, on attempts to disconnect */
+	error = -EALREADY;
+	if ((sk->sk_state & PPPOX_DEAD) && !sp->sa_addr.pppoe.sid )
+		goto end;
+
+	error = 0;
+	if (po->pppoe_pa.sid) {
+		pppox_unbind_sock(sk);
+
+		/* Delete the old binding */
+		delete_item(po->pppoe_pa.sid,po->pppoe_pa.remote);
+
+		if(po->pppoe_dev)
+			dev_put(po->pppoe_dev);
+
+		memset(sk_pppox(po) + 1, 0,
+		       sizeof(struct pppox_sock) - sizeof(struct sock));
+
+		sk->sk_state = PPPOX_NONE;
+	}
+
+	/* Don't re-bind if sid==0 */
+	if (sp->sa_addr.pppoe.sid != 0) {
+		dev = dev_get_by_name(sp->sa_addr.pppoe.dev);
+
+		error = -ENODEV;
+		if (!dev)
+			goto end;
+
+		po->pppoe_dev = dev;
+
+		if (!(dev->flags & IFF_UP))
+			goto err_put;
+
+		memcpy(&po->pppoe_pa,
+		       &sp->sa_addr.pppoe,
+		       sizeof(struct pppoe_addr));
+
+		error = set_item(po);
+		if (error < 0)
+			goto err_put;
+
+		po->chan.hdrlen = (sizeof(struct pppoe_hdr) +
+				   dev->hard_header_len);
+
+		po->chan.private = sk;
+		po->chan.ops = &pppoe_chan_ops;
+
+		error = ppp_register_channel(&po->chan);
+		if (error)
+			goto err_put;
+
+		sk->sk_state = PPPOX_CONNECTED;
+	}
+
+	po->num = sp->sa_addr.pppoe.sid;
+
+ end:
+	release_sock(sk);
+	return error;
+err_put:
+	if (po->pppoe_dev) {
+		dev_put(po->pppoe_dev);
+		po->pppoe_dev = NULL;
+	}
+	goto end;
+}
+
+
+static int pppoe_getname(struct socket *sock, struct sockaddr *uaddr,
+		  int *usockaddr_len, int peer)
+{
+	int len = sizeof(struct sockaddr_pppox);
+	struct sockaddr_pppox sp;
+
+	sp.sa_family	= AF_PPPOX;
+	sp.sa_protocol	= PX_PROTO_OE;
+	memcpy(&sp.sa_addr.pppoe, &pppox_sk(sock->sk)->pppoe_pa,
+	       sizeof(struct pppoe_addr));
+
+	memcpy(uaddr, &sp, len);
+
+	*usockaddr_len = len;
+
+	return 0;
+}
+
+
+static int pppoe_ioctl(struct socket *sock, unsigned int cmd,
+		unsigned long arg)
+{
+	struct sock *sk = sock->sk;
+	struct pppox_sock *po = pppox_sk(sk);
+	int val = 0;
+	int err = 0;
+
+	switch (cmd) {
+	case PPPIOCGMRU:
+		err = -ENXIO;
+
+		if (!(sk->sk_state & PPPOX_CONNECTED))
+			break;
+
+		err = -EFAULT;
+		if (put_user(po->pppoe_dev->mtu -
+			     sizeof(struct pppoe_hdr) -
+			     PPP_HDRLEN,
+			     (int __user *) arg))
+			break;
+		err = 0;
+		break;
+
+	case PPPIOCSMRU:
+		err = -ENXIO;
+		if (!(sk->sk_state & PPPOX_CONNECTED))
+			break;
+
+		err = -EFAULT;
+		if (get_user(val,(int __user *) arg))
+			break;
+
+		if (val < (po->pppoe_dev->mtu
+			   - sizeof(struct pppoe_hdr)
+			   - PPP_HDRLEN))
+			err = 0;
+		else
+			err = -EINVAL;
+		break;
+
+	case PPPIOCSFLAGS:
+		err = -EFAULT;
+		if (get_user(val, (int __user *) arg))
+			break;
+		err = 0;
+		break;
+
+	case PPPOEIOCSFWD:
+	{
+		struct pppox_sock *relay_po;
+
+		err = -EBUSY;
+		if (sk->sk_state & (PPPOX_BOUND | PPPOX_ZOMBIE | PPPOX_DEAD))
+			break;
+
+		err = -ENOTCONN;
+		if (!(sk->sk_state & PPPOX_CONNECTED))
+			break;
+
+		/* PPPoE address from the user specifies an outbound
+		   PPPoE address to which frames are forwarded to */
+		err = -EFAULT;
+		if (copy_from_user(&po->pppoe_relay,
+				   (void __user *)arg,
+				   sizeof(struct sockaddr_pppox)))
+			break;
+
+		err = -EINVAL;
+		if (po->pppoe_relay.sa_family != AF_PPPOX ||
+		    po->pppoe_relay.sa_protocol!= PX_PROTO_OE)
+			break;
+
+		/* Check that the socket referenced by the address
+		   actually exists. */
+		relay_po = get_item_by_addr(&po->pppoe_relay);
+
+		if (!relay_po)
+			break;
+
+		sock_put(sk_pppox(relay_po));
+		sk->sk_state |= PPPOX_RELAY;
+		err = 0;
+		break;
+	}
+
+	case PPPOEIOCDFWD:
+		err = -EALREADY;
+		if (!(sk->sk_state & PPPOX_RELAY))
+			break;
+
+		sk->sk_state &= ~PPPOX_RELAY;
+		err = 0;
+		break;
+
+	default:;
+	};
+
+	return err;
+}
+
+
+static int pppoe_sendmsg(struct kiocb *iocb, struct socket *sock, 
+		  struct msghdr *m, size_t total_len)
+{
+	struct sk_buff *skb = NULL;
+	struct sock *sk = sock->sk;
+	struct pppox_sock *po = pppox_sk(sk);
+	int error = 0;
+	struct pppoe_hdr hdr;
+	struct pppoe_hdr *ph;
+	struct net_device *dev;
+	char *start;
+
+	if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) {
+		error = -ENOTCONN;
+		goto end;
+	}
+
+	hdr.ver = 1;
+	hdr.type = 1;
+	hdr.code = 0;
+	hdr.sid = po->num;
+
+	lock_sock(sk);
+
+	dev = po->pppoe_dev;
+
+	error = -EMSGSIZE;
+ 	if (total_len > (dev->mtu + dev->hard_header_len))
+		goto end;
+
+
+	skb = sock_wmalloc(sk, total_len + dev->hard_header_len + 32,
+			   0, GFP_KERNEL);
+	if (!skb) {
+		error = -ENOMEM;
+		goto end;
+	}
+
+	/* Reserve space for headers. */
+	skb_reserve(skb, dev->hard_header_len);
+	skb->nh.raw = skb->data;
+
+	skb->dev = dev;
+
+	skb->priority = sk->sk_priority;
+	skb->protocol = __constant_htons(ETH_P_PPP_SES);
+
+	ph = (struct pppoe_hdr *) skb_put(skb, total_len + sizeof(struct pppoe_hdr));
+	start = (char *) &ph->tag[0];
+
+	error = memcpy_fromiovec(start, m->msg_iov, total_len);
+
+	if (error < 0) {
+		kfree_skb(skb);
+		goto end;
+	}
+
+	error = total_len;
+	dev->hard_header(skb, dev, ETH_P_PPP_SES,
+			 po->pppoe_pa.remote, NULL, total_len);
+
+	memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
+
+	ph->length = htons(total_len);
+
+	dev_queue_xmit(skb);
+
+end:
+	release_sock(sk);
+	return error;
+}
+
+
+/************************************************************************
+ *
+ * xmit function for internal use.
+ *
+ ***********************************************************************/
+static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb)
+{
+	struct pppox_sock *po = pppox_sk(sk);
+	struct net_device *dev = po->pppoe_dev;
+	struct pppoe_hdr hdr;
+	struct pppoe_hdr *ph;
+	int headroom = skb_headroom(skb);
+	int data_len = skb->len;
+	struct sk_buff *skb2;
+
+	if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
+		goto abort;
+
+	hdr.ver	= 1;
+	hdr.type = 1;
+	hdr.code = 0;
+	hdr.sid	= po->num;
+	hdr.length = htons(skb->len);
+
+	if (!dev)
+		goto abort;
+
+	/* Copy the skb if there is no space for the header. */
+	if (headroom < (sizeof(struct pppoe_hdr) + dev->hard_header_len)) {
+		skb2 = dev_alloc_skb(32+skb->len +
+				     sizeof(struct pppoe_hdr) +
+				     dev->hard_header_len);
+
+		if (skb2 == NULL)
+			goto abort;
+
+		skb_reserve(skb2, dev->hard_header_len + sizeof(struct pppoe_hdr));
+		memcpy(skb_put(skb2, skb->len), skb->data, skb->len);
+	} else {
+		/* Make a clone so as to not disturb the original skb,
+		 * give dev_queue_xmit something it can free.
+		 */
+		skb2 = skb_clone(skb, GFP_ATOMIC);
+	}
+
+	ph = (struct pppoe_hdr *) skb_push(skb2, sizeof(struct pppoe_hdr));
+	memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
+	skb2->protocol = __constant_htons(ETH_P_PPP_SES);
+
+	skb2->nh.raw = skb2->data;
+
+	skb2->dev = dev;
+
+	dev->hard_header(skb2, dev, ETH_P_PPP_SES,
+			 po->pppoe_pa.remote, NULL, data_len);
+
+	/* We're transmitting skb2, and assuming that dev_queue_xmit
+	 * will free it.  The generic ppp layer however, is expecting
+	 * that we give back 'skb' (not 'skb2') in case of failure,
+	 * but free it in case of success.
+	 */
+
+	if (dev_queue_xmit(skb2) < 0)
+		goto abort;
+
+	kfree_skb(skb);
+	return 1;
+
+abort:
+	return 0;
+}
+
+
+/************************************************************************
+ *
+ * xmit function called by generic PPP driver
+ * sends PPP frame over PPPoE socket
+ *
+ ***********************************************************************/
+static int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb)
+{
+	struct sock *sk = (struct sock *) chan->private;
+	return __pppoe_xmit(sk, skb);
+}
+
+
+static struct ppp_channel_ops pppoe_chan_ops = { 
+	.start_xmit = pppoe_xmit, 
+};
+
+static int pppoe_recvmsg(struct kiocb *iocb, struct socket *sock,
+		  struct msghdr *m, size_t total_len, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct sk_buff *skb = NULL;
+	int error = 0;
+	int len;
+	struct pppoe_hdr *ph = NULL;
+
+	if (sk->sk_state & PPPOX_BOUND) {
+		error = -EIO;
+		goto end;
+	}
+
+	skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
+				flags & MSG_DONTWAIT, &error);
+
+	if (error < 0) {
+		goto end;
+	}
+
+	m->msg_namelen = 0;
+
+	if (skb) {
+		error = 0;
+		ph = (struct pppoe_hdr *) skb->nh.raw;
+		len = ntohs(ph->length);
+
+		error = memcpy_toiovec(m->msg_iov, (unsigned char *) &ph->tag[0], len);
+		if (error < 0)
+			goto do_skb_free;
+		error = len;
+	}
+
+do_skb_free:
+	if (skb)
+		kfree_skb(skb);
+end:
+	return error;
+}
+
+#ifdef CONFIG_PROC_FS
+static int pppoe_seq_show(struct seq_file *seq, void *v)
+{
+	struct pppox_sock *po;
+	char *dev_name;
+
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq, "Id       Address              Device\n");
+		goto out;
+	}
+
+	po = v;
+	dev_name = po->pppoe_pa.dev;
+
+	seq_printf(seq, "%08X %02X:%02X:%02X:%02X:%02X:%02X %8s\n",
+		   po->pppoe_pa.sid,
+		   po->pppoe_pa.remote[0], po->pppoe_pa.remote[1],
+		   po->pppoe_pa.remote[2], po->pppoe_pa.remote[3],
+		   po->pppoe_pa.remote[4], po->pppoe_pa.remote[5], dev_name);
+out:
+	return 0;
+}
+
+static __inline__ struct pppox_sock *pppoe_get_idx(loff_t pos)
+{
+	struct pppox_sock *po = NULL;
+	int i = 0;
+
+	for (; i < PPPOE_HASH_SIZE; i++) {
+		po = item_hash_table[i];
+		while (po) {
+			if (!pos--)
+				goto out;
+			po = po->next;
+		}
+	}
+out:
+	return po;
+}
+
+static void *pppoe_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	loff_t l = *pos;
+
+	read_lock_bh(&pppoe_hash_lock);
+	return l ? pppoe_get_idx(--l) : SEQ_START_TOKEN;
+}
+
+static void *pppoe_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct pppox_sock *po;
+
+	++*pos;
+	if (v == SEQ_START_TOKEN) {
+		po = pppoe_get_idx(0);
+		goto out;
+	}
+	po = v;
+	if (po->next) 
+		po = po->next;
+	else {
+		int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
+
+		while (++hash < PPPOE_HASH_SIZE) {
+			po = item_hash_table[hash];
+			if (po)
+				break;
+		}
+	}
+out:
+	return po;
+}
+
+static void pppoe_seq_stop(struct seq_file *seq, void *v)
+{
+	read_unlock_bh(&pppoe_hash_lock);
+}
+
+static struct seq_operations pppoe_seq_ops = {
+	.start		= pppoe_seq_start,
+	.next		= pppoe_seq_next,
+	.stop		= pppoe_seq_stop,
+	.show		= pppoe_seq_show,
+};
+
+static int pppoe_seq_open(struct inode *inode, struct file *file)
+{
+	return seq_open(file, &pppoe_seq_ops);
+}
+
+static struct file_operations pppoe_seq_fops = {
+	.owner		= THIS_MODULE,
+	.open		= pppoe_seq_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release,
+};
+
+static int __init pppoe_proc_init(void)
+{
+	struct proc_dir_entry *p;
+
+	p = create_proc_entry("pppoe", S_IRUGO, proc_net);
+	if (!p)
+		return -ENOMEM;
+
+	p->proc_fops = &pppoe_seq_fops;
+	return 0;
+}
+#else /* CONFIG_PROC_FS */
+static inline int pppoe_proc_init(void) { return 0; }
+#endif /* CONFIG_PROC_FS */
+
+/* ->ioctl are set at pppox_create */
+
+static struct proto_ops pppoe_ops = {
+    .family		= AF_PPPOX,
+    .owner		= THIS_MODULE,
+    .release		= pppoe_release,
+    .bind		= sock_no_bind,
+    .connect		= pppoe_connect,
+    .socketpair		= sock_no_socketpair,
+    .accept		= sock_no_accept,
+    .getname		= pppoe_getname,
+    .poll		= datagram_poll,
+    .listen		= sock_no_listen,
+    .shutdown		= sock_no_shutdown,
+    .setsockopt		= sock_no_setsockopt,
+    .getsockopt		= sock_no_getsockopt,
+    .sendmsg		= pppoe_sendmsg,
+    .recvmsg		= pppoe_recvmsg,
+    .mmap		= sock_no_mmap
+};
+
+static struct pppox_proto pppoe_proto = {
+    .create	= pppoe_create,
+    .ioctl	= pppoe_ioctl,
+    .owner	= THIS_MODULE,
+};
+
+
+static int __init pppoe_init(void)
+{
+	int err = proto_register(&pppoe_sk_proto, 0);
+
+	if (err)
+		goto out;
+
+ 	err = register_pppox_proto(PX_PROTO_OE, &pppoe_proto);
+	if (err)
+		goto out_unregister_pppoe_proto;
+
+	err = pppoe_proc_init();
+	if (err)
+		goto out_unregister_pppox_proto;
+	
+	dev_add_pack(&pppoes_ptype);
+	dev_add_pack(&pppoed_ptype);
+	register_netdevice_notifier(&pppoe_notifier);
+out:
+	return err;
+out_unregister_pppox_proto:
+	unregister_pppox_proto(PX_PROTO_OE);
+out_unregister_pppoe_proto:
+	proto_unregister(&pppoe_sk_proto);
+	goto out;
+}
+
+static void __exit pppoe_exit(void)
+{
+	unregister_pppox_proto(PX_PROTO_OE);
+	dev_remove_pack(&pppoes_ptype);
+	dev_remove_pack(&pppoed_ptype);
+	unregister_netdevice_notifier(&pppoe_notifier);
+	remove_proc_entry("pppoe", proc_net);
+	proto_unregister(&pppoe_sk_proto);
+}
+
+module_init(pppoe_init);
+module_exit(pppoe_exit);
+
+MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
+MODULE_DESCRIPTION("PPP over Ethernet driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(PF_PPPOX);