/*
   * DECnet       An implementation of the DECnet protocol suite for the LINUX
   *              operating system.  DECnet is implemented using the  BSD Socket
   *              interface as the means of communication with the user level.
   *
   *              DECnet Socket Layer Interface
   *
   * Authors:     Eduardo Marcelo Serrat <emserrat@geocities.com>
   *              Patrick Caulfield <patrick@pandh.demon.co.uk>
   *
   * Changes:
   *        Steve Whitehouse: Copied from Eduardo Serrat and Patrick Caulfield's
   *                          version of the code. Original copyright preserved
   *                          below.
   *        Steve Whitehouse: Some bug fixes, cleaning up some code to make it
   *                          compatible with my routing layer.
   *        Steve Whitehouse: Merging changes from Eduardo Serrat and Patrick
   *                          Caulfield.
   *        Steve Whitehouse: Further bug fixes, checking module code still works
   *                          with new routing layer.
   *        Steve Whitehouse: Additional set/get_sockopt() calls.
   *        Steve Whitehouse: Fixed TIOCINQ ioctl to be same as Eduardo's new
   *                          code.
   *        Steve Whitehouse: recvmsg() changed to try and behave in a POSIX like
   *                          way. Didn't manage it entirely, but its better.
   *        Steve Whitehouse: ditto for sendmsg().
   *        Steve Whitehouse: A selection of bug fixes to various things.
   *        Steve Whitehouse: Added TIOCOUTQ ioctl.
   *        Steve Whitehouse: Fixes to username2sockaddr & sockaddr2username.
   *        Steve Whitehouse: Fixes to connect() error returns.
   *       Patrick Caulfield: Fixes to delayed acceptance logic.
   *         David S. Miller: New socket locking
   *        Steve Whitehouse: Socket list hashing/locking
   *         Arnaldo C. Melo: use capable, not suser
   *        Steve Whitehouse: Removed unused code. Fix to use sk->allocation
   *                          when required.
   *       Patrick Caulfield: /proc/net/decnet now has object name/number
   *        Steve Whitehouse: Fixed local port allocation, hashed sk list
   *          Matthew Wilcox: Fixes for dn_ioctl()
   *        Steve Whitehouse: New connect/accept logic to allow timeouts and
   *                          prepare for sendpage etc.
   */
  
  
  /******************************************************************************
      (c) 1995-1998 E.M. Serrat		emserrat@geocities.com

      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
      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.
  
  HISTORY:
  
  Version           Kernel     Date       Author/Comments
  -------           ------     ----       ---------------
  Version 0.0.1     2.0.30    01-dic-97	Eduardo Marcelo Serrat
  					(emserrat@geocities.com)

  					First Development of DECnet Socket La-

  					yer for Linux. Only supports outgoing
  					connections.
  
  Version 0.0.2	  2.1.105   20-jun-98   Patrick J. Caulfield
  					(patrick@pandh.demon.co.uk)
  
  					Port to new kernel development version.
  
  Version 0.0.3     2.1.106   25-jun-98   Eduardo Marcelo Serrat
  					(emserrat@geocities.com)
  					_

  					Added support for incoming connections
  					so we can start developing server apps
  					on Linux.

  					-
  					Module Support
  Version 0.0.4     2.1.109   21-jul-98   Eduardo Marcelo Serrat

  				       (emserrat@geocities.com)
  				       _
  					Added support for X11R6.4. Now we can
  					use DECnet transport for X on Linux!!!
  				       -

  Version 0.0.5    2.1.110   01-aug-98   Eduardo Marcelo Serrat

  				       (emserrat@geocities.com)
  				       Removed bugs on flow control
  				       Removed bugs on incoming accessdata
  				       order
  				       -

  Version 0.0.6    2.1.110   07-aug-98   Eduardo Marcelo Serrat

  				       dn_recvmsg fixes

  					Patrick J. Caulfield
  				       dn_bind fixes

  *******************************************************************************/

  #include <linux/module.h>
  #include <linux/errno.h>
  #include <linux/types.h>
  #include <linux/slab.h>
  #include <linux/socket.h>
  #include <linux/in.h>
  #include <linux/kernel.h>
  #include <linux/sched.h>
  #include <linux/timer.h>
  #include <linux/string.h>
  #include <linux/sockios.h>
  #include <linux/net.h>
  #include <linux/netdevice.h>
  #include <linux/inet.h>
  #include <linux/route.h>
  #include <linux/netfilter.h>
  #include <linux/seq_file.h>
  #include <net/sock.h>

  #include <net/tcp_states.h>

  #include <net/flow.h>
  #include <asm/system.h>
  #include <asm/ioctls.h>

  #include <linux/capability.h>

  #include <linux/mm.h>
  #include <linux/interrupt.h>
  #include <linux/proc_fs.h>
  #include <linux/stat.h>
  #include <linux/init.h>
  #include <linux/poll.h>

  #include <net/net_namespace.h>

  #include <net/neighbour.h>
  #include <net/dst.h>

  #include <net/fib_rules.h>

  #include <net/dn.h>
  #include <net/dn_nsp.h>
  #include <net/dn_dev.h>
  #include <net/dn_route.h>
  #include <net/dn_fib.h>
  #include <net/dn_neigh.h>
  
  struct dn_sock {
  	struct sock sk;
  	struct dn_scp scp;
  };
  
  static void dn_keepalive(struct sock *sk);
  
  #define DN_SK_HASH_SHIFT 8
  #define DN_SK_HASH_SIZE (1 << DN_SK_HASH_SHIFT)
  #define DN_SK_HASH_MASK (DN_SK_HASH_SIZE - 1)

  static const struct proto_ops dn_proto_ops;

  static DEFINE_RWLOCK(dn_hash_lock);
  static struct hlist_head dn_sk_hash[DN_SK_HASH_SIZE];
  static struct hlist_head dn_wild_sk;

  static atomic_t decnet_memory_allocated;

  
  static int __dn_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen, int flags);
  static int __dn_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen, int flags);
  
  static struct hlist_head *dn_find_list(struct sock *sk)
  {
  	struct dn_scp *scp = DN_SK(sk);
  
  	if (scp->addr.sdn_flags & SDF_WILD)
  		return hlist_empty(&dn_wild_sk) ? &dn_wild_sk : NULL;

  	return &dn_sk_hash[dn_ntohs(scp->addrloc) & DN_SK_HASH_MASK];

  }

  /*

   * Valid ports are those greater than zero and not already in use.
   */

  static int check_port(__le16 port)

  {
  	struct sock *sk;
  	struct hlist_node *node;
  
  	if (port == 0)
  		return -1;

  	sk_for_each(sk, node, &dn_sk_hash[dn_ntohs(port) & DN_SK_HASH_MASK]) {

  		struct dn_scp *scp = DN_SK(sk);
  		if (scp->addrloc == port)
  			return -1;
  	}
  	return 0;
  }
  
  static unsigned short port_alloc(struct sock *sk)
  {
  	struct dn_scp *scp = DN_SK(sk);
  static unsigned short port = 0x2000;
  	unsigned short i_port = port;

  	while(check_port(dn_htons(++port)) != 0) {

  		if (port == i_port)
  			return 0;
  	}

  	scp->addrloc = dn_htons(port);

  
  	return 1;
  }
  
  /*
   * Since this is only ever called from user
   * level, we don't need a write_lock() version
   * of this.
   */
  static int dn_hash_sock(struct sock *sk)
  {
  	struct dn_scp *scp = DN_SK(sk);
  	struct hlist_head *list;
  	int rv = -EUSERS;
  
  	BUG_ON(sk_hashed(sk));
  
  	write_lock_bh(&dn_hash_lock);

  	if (!scp->addrloc && !port_alloc(sk))
  		goto out;
  
  	rv = -EADDRINUSE;
  	if ((list = dn_find_list(sk)) == NULL)
  		goto out;
  
  	sk_add_node(sk, list);
  	rv = 0;
  out:
  	write_unlock_bh(&dn_hash_lock);
  	return rv;
  }
  
  static void dn_unhash_sock(struct sock *sk)
  {
  	write_lock(&dn_hash_lock);
  	sk_del_node_init(sk);
  	write_unlock(&dn_hash_lock);
  }
  
  static void dn_unhash_sock_bh(struct sock *sk)
  {
  	write_lock_bh(&dn_hash_lock);
  	sk_del_node_init(sk);
  	write_unlock_bh(&dn_hash_lock);
  }
  
  static struct hlist_head *listen_hash(struct sockaddr_dn *addr)
  {
  	int i;
  	unsigned hash = addr->sdn_objnum;
  
  	if (hash == 0) {
  		hash = addr->sdn_objnamel;
  		for(i = 0; i < dn_ntohs(addr->sdn_objnamel); i++) {
  			hash ^= addr->sdn_objname[i];
  			hash ^= (hash << 3);
  		}
  	}
  
  	return &dn_sk_hash[hash & DN_SK_HASH_MASK];
  }
  
  /*
   * Called to transform a socket from bound (i.e. with a local address)
   * into a listening socket (doesn't need a local port number) and rehashes
   * based upon the object name/number.
   */
  static void dn_rehash_sock(struct sock *sk)
  {
  	struct hlist_head *list;
  	struct dn_scp *scp = DN_SK(sk);
  
  	if (scp->addr.sdn_flags & SDF_WILD)
  		return;
  
  	write_lock_bh(&dn_hash_lock);
  	sk_del_node_init(sk);
  	DN_SK(sk)->addrloc = 0;
  	list = listen_hash(&DN_SK(sk)->addr);
  	sk_add_node(sk, list);
  	write_unlock_bh(&dn_hash_lock);
  }
  
  int dn_sockaddr2username(struct sockaddr_dn *sdn, unsigned char *buf, unsigned char type)
  {
  	int len = 2;
  
  	*buf++ = type;
  
  	switch(type) {
  		case 0:
  			*buf++ = sdn->sdn_objnum;
  			break;
  		case 1:
  			*buf++ = 0;
  			*buf++ = dn_ntohs(sdn->sdn_objnamel);
  			memcpy(buf, sdn->sdn_objname, dn_ntohs(sdn->sdn_objnamel));
  			len = 3 + dn_ntohs(sdn->sdn_objnamel);
  			break;
  		case 2:
  			memset(buf, 0, 5);
  			buf += 5;
  			*buf++ = dn_ntohs(sdn->sdn_objnamel);
  			memcpy(buf, sdn->sdn_objname, dn_ntohs(sdn->sdn_objnamel));
  			len = 7 + dn_ntohs(sdn->sdn_objnamel);
  			break;
  	}
  
  	return len;
  }
  
  /*
   * On reception of usernames, we handle types 1 and 0 for destination
   * addresses only. Types 2 and 4 are used for source addresses, but the
   * UIC, GIC are ignored and they are both treated the same way. Type 3
   * is never used as I've no idea what its purpose might be or what its
   * format is.
   */
  int dn_username2sockaddr(unsigned char *data, int len, struct sockaddr_dn *sdn, unsigned char *fmt)
  {
  	unsigned char type;
  	int size = len;
  	int namel = 12;
  
  	sdn->sdn_objnum = 0;
  	sdn->sdn_objnamel = dn_htons(0);
  	memset(sdn->sdn_objname, 0, DN_MAXOBJL);
  
  	if (len < 2)
  		return -1;
  
  	len -= 2;
  	*fmt = *data++;
  	type = *data++;
  
  	switch(*fmt) {
  		case 0:
  			sdn->sdn_objnum = type;
  			return 2;
  		case 1:
  			namel = 16;
  			break;
  		case 2:
  			len  -= 4;
  			data += 4;
  			break;
  		case 4:
  			len  -= 8;
  			data += 8;
  			break;
  		default:
  			return -1;
  	}
  
  	len -= 1;
  
  	if (len < 0)
  		return -1;
  
  	sdn->sdn_objnamel = dn_htons(*data++);
  	len -= dn_ntohs(sdn->sdn_objnamel);
  
  	if ((len < 0) || (dn_ntohs(sdn->sdn_objnamel) > namel))
  		return -1;
  
  	memcpy(sdn->sdn_objname, data, dn_ntohs(sdn->sdn_objnamel));
  
  	return size - len;
  }
  
  struct sock *dn_sklist_find_listener(struct sockaddr_dn *addr)
  {
  	struct hlist_head *list = listen_hash(addr);
  	struct hlist_node *node;
  	struct sock *sk;
  
  	read_lock(&dn_hash_lock);
  	sk_for_each(sk, node, list) {
  		struct dn_scp *scp = DN_SK(sk);
  		if (sk->sk_state != TCP_LISTEN)
  			continue;
  		if (scp->addr.sdn_objnum) {
  			if (scp->addr.sdn_objnum != addr->sdn_objnum)
  				continue;
  		} else {
  			if (addr->sdn_objnum)
  				continue;
  			if (scp->addr.sdn_objnamel != addr->sdn_objnamel)
  				continue;
  			if (memcmp(scp->addr.sdn_objname, addr->sdn_objname, dn_ntohs(addr->sdn_objnamel)) != 0)
  				continue;
  		}
  		sock_hold(sk);
  		read_unlock(&dn_hash_lock);
  		return sk;
  	}
  
  	sk = sk_head(&dn_wild_sk);
  	if (sk) {

  		if (sk->sk_state == TCP_LISTEN)

  			sock_hold(sk);
  		else
  			sk = NULL;
  	}
  
  	read_unlock(&dn_hash_lock);
  	return sk;
  }
  
  struct sock *dn_find_by_skb(struct sk_buff *skb)
  {
  	struct dn_skb_cb *cb = DN_SKB_CB(skb);
  	struct sock *sk;
  	struct hlist_node *node;
  	struct dn_scp *scp;
  
  	read_lock(&dn_hash_lock);

  	sk_for_each(sk, node, &dn_sk_hash[dn_ntohs(cb->dst_port) & DN_SK_HASH_MASK]) {

  		scp = DN_SK(sk);
  		if (cb->src != dn_saddr2dn(&scp->peer))
  			continue;
  		if (cb->dst_port != scp->addrloc)
  			continue;
  		if (scp->addrrem && (cb->src_port != scp->addrrem))
  			continue;
  		sock_hold(sk);
  		goto found;
  	}
  	sk = NULL;
  found:
  	read_unlock(&dn_hash_lock);
  	return sk;
  }
  
  
  
  static void dn_destruct(struct sock *sk)
  {
  	struct dn_scp *scp = DN_SK(sk);
  
  	skb_queue_purge(&scp->data_xmit_queue);
  	skb_queue_purge(&scp->other_xmit_queue);
  	skb_queue_purge(&scp->other_receive_queue);
  
  	dst_release(xchg(&sk->sk_dst_cache, NULL));
  }

  static int dn_memory_pressure;

  static void dn_enter_memory_pressure(struct sock *sk)

  {
  	if (!dn_memory_pressure) {
  		dn_memory_pressure = 1;
  	}
  }

  static struct proto dn_proto = {

  	.name			= "NSP",
  	.owner			= THIS_MODULE,
  	.enter_memory_pressure	= dn_enter_memory_pressure,
  	.memory_pressure	= &dn_memory_pressure,
  	.memory_allocated	= &decnet_memory_allocated,
  	.sysctl_mem		= sysctl_decnet_mem,
  	.sysctl_wmem		= sysctl_decnet_wmem,
  	.sysctl_rmem		= sysctl_decnet_rmem,
  	.max_header		= DN_MAX_NSP_DATA_HEADER + 64,
  	.obj_size		= sizeof(struct dn_sock),

  };

  static struct sock *dn_alloc_sock(struct net *net, struct socket *sock, gfp_t gfp)

  {
  	struct dn_scp *scp;

  	struct sock *sk = sk_alloc(net, PF_DECnet, gfp, &dn_proto);

  
  	if  (!sk)
  		goto out;
  
  	if (sock)
  		sock->ops = &dn_proto_ops;
  	sock_init_data(sock, sk);
  
  	sk->sk_backlog_rcv = dn_nsp_backlog_rcv;
  	sk->sk_destruct    = dn_destruct;
  	sk->sk_no_check    = 1;
  	sk->sk_family      = PF_DECnet;
  	sk->sk_protocol    = 0;
  	sk->sk_allocation  = gfp;

  	sk->sk_sndbuf	   = sysctl_decnet_wmem[1];
  	sk->sk_rcvbuf	   = sysctl_decnet_rmem[1];

  
  	/* Initialization of DECnet Session Control Port		*/
  	scp = DN_SK(sk);
  	scp->state	= DN_O;		/* Open			*/
  	scp->numdat	= 1;		/* Next data seg to tx	*/
  	scp->numoth	= 1;		/* Next oth data to tx  */
  	scp->ackxmt_dat = 0;		/* Last data seg ack'ed */
  	scp->ackxmt_oth = 0;		/* Last oth data ack'ed */
  	scp->ackrcv_dat = 0;		/* Highest data ack recv*/
  	scp->ackrcv_oth = 0;		/* Last oth data ack rec*/

  	scp->flowrem_sw = DN_SEND;

  	scp->flowloc_sw = DN_SEND;
  	scp->flowrem_dat = 0;
  	scp->flowrem_oth = 1;
  	scp->flowloc_dat = 0;
  	scp->flowloc_oth = 1;
  	scp->services_rem = 0;
  	scp->services_loc = 1 | NSP_FC_NONE;
  	scp->info_rem = 0;
  	scp->info_loc = 0x03; /* NSP version 4.1 */
  	scp->segsize_rem = 230 - DN_MAX_NSP_DATA_HEADER; /* Default: Updated by remote segsize */
  	scp->nonagle = 0;
  	scp->multi_ireq = 1;
  	scp->accept_mode = ACC_IMMED;
  	scp->addr.sdn_family    = AF_DECnet;
  	scp->peer.sdn_family    = AF_DECnet;
  	scp->accessdata.acc_accl = 5;
  	memcpy(scp->accessdata.acc_acc, "LINUX", 5);
  
  	scp->max_window   = NSP_MAX_WINDOW;
  	scp->snd_window   = NSP_MIN_WINDOW;
  	scp->nsp_srtt     = NSP_INITIAL_SRTT;
  	scp->nsp_rttvar   = NSP_INITIAL_RTTVAR;
  	scp->nsp_rxtshift = 0;
  
  	skb_queue_head_init(&scp->data_xmit_queue);
  	skb_queue_head_init(&scp->other_xmit_queue);
  	skb_queue_head_init(&scp->other_receive_queue);
  
  	scp->persist = 0;
  	scp->persist_fxn = NULL;
  	scp->keepalive = 10 * HZ;
  	scp->keepalive_fxn = dn_keepalive;
  
  	init_timer(&scp->delack_timer);
  	scp->delack_pending = 0;
  	scp->delack_fxn = dn_nsp_delayed_ack;
  
  	dn_start_slow_timer(sk);
  out:
  	return sk;
  }
  
  /*
   * Keepalive timer.
   * FIXME: Should respond to SO_KEEPALIVE etc.
   */
  static void dn_keepalive(struct sock *sk)
  {
  	struct dn_scp *scp = DN_SK(sk);
  
  	/*
  	 * By checking the other_data transmit queue is empty
  	 * we are double checking that we are not sending too
  	 * many of these keepalive frames.
  	 */

  	if (skb_queue_empty(&scp->other_xmit_queue))

  		dn_nsp_send_link(sk, DN_NOCHANGE, 0);
  }
  
  
  /*
   * Timer for shutdown/destroyed sockets.
   * When socket is dead & no packets have been sent for a
   * certain amount of time, they are removed by this
   * routine. Also takes care of sending out DI & DC
   * frames at correct times.
   */
  int dn_destroy_timer(struct sock *sk)
  {
  	struct dn_scp *scp = DN_SK(sk);
  
  	scp->persist = dn_nsp_persist(sk);
  
  	switch(scp->state) {
  		case DN_DI:
  			dn_nsp_send_disc(sk, NSP_DISCINIT, 0, GFP_ATOMIC);
  			if (scp->nsp_rxtshift >= decnet_di_count)
  				scp->state = DN_CN;
  			return 0;
  
  		case DN_DR:
  			dn_nsp_send_disc(sk, NSP_DISCINIT, 0, GFP_ATOMIC);
  			if (scp->nsp_rxtshift >= decnet_dr_count)
  				scp->state = DN_DRC;
  			return 0;
  
  		case DN_DN:
  			if (scp->nsp_rxtshift < decnet_dn_count) {
  				/* printk(KERN_DEBUG "dn_destroy_timer: DN
  "); */
  				dn_nsp_send_disc(sk, NSP_DISCCONF, NSP_REASON_DC, GFP_ATOMIC);
  				return 0;
  			}
  	}
  
  	scp->persist = (HZ * decnet_time_wait);
  
  	if (sk->sk_socket)
  		return 0;
  
  	if ((jiffies - scp->stamp) >= (HZ * decnet_time_wait)) {
  		dn_unhash_sock(sk);
  		sock_put(sk);
  		return 1;
  	}
  
  	return 0;
  }
  
  static void dn_destroy_sock(struct sock *sk)
  {
  	struct dn_scp *scp = DN_SK(sk);
  
  	scp->nsp_rxtshift = 0; /* reset back off */
  
  	if (sk->sk_socket) {
  		if (sk->sk_socket->state != SS_UNCONNECTED)
  			sk->sk_socket->state = SS_DISCONNECTING;
  	}
  
  	sk->sk_state = TCP_CLOSE;
  
  	switch(scp->state) {
  		case DN_DN:
  			dn_nsp_send_disc(sk, NSP_DISCCONF, NSP_REASON_DC,
  					 sk->sk_allocation);
  			scp->persist_fxn = dn_destroy_timer;
  			scp->persist = dn_nsp_persist(sk);
  			break;
  		case DN_CR:
  			scp->state = DN_DR;
  			goto disc_reject;
  		case DN_RUN:
  			scp->state = DN_DI;
  		case DN_DI:
  		case DN_DR:
  disc_reject:
  			dn_nsp_send_disc(sk, NSP_DISCINIT, 0, sk->sk_allocation);
  		case DN_NC:
  		case DN_NR:
  		case DN_RJ:
  		case DN_DIC:
  		case DN_CN:
  		case DN_DRC:
  		case DN_CI:
  		case DN_CD:
  			scp->persist_fxn = dn_destroy_timer;
  			scp->persist = dn_nsp_persist(sk);
  			break;
  		default:
  			printk(KERN_DEBUG "DECnet: dn_destroy_sock passed socket in invalid state
  ");
  		case DN_O:
  			dn_stop_slow_timer(sk);
  
  			dn_unhash_sock_bh(sk);
  			sock_put(sk);
  
  			break;
  	}
  }

  char *dn_addr2asc(__u16 addr, char *buf)

  {
  	unsigned short node, area;
  
  	node = addr & 0x03ff;
  	area = addr >> 10;
  	sprintf(buf, "%hd.%hd", area, node);
  
  	return buf;
  }

  static int dn_create(struct net *net, struct socket *sock, int protocol)

  {
  	struct sock *sk;

  	if (net != &init_net)
  		return -EAFNOSUPPORT;

  	switch(sock->type) {
  		case SOCK_SEQPACKET:
  			if (protocol != DNPROTO_NSP)
  				return -EPROTONOSUPPORT;
  			break;
  		case SOCK_STREAM:
  			break;
  		default:
  			return -ESOCKTNOSUPPORT;
  	}

  	if ((sk = dn_alloc_sock(net, sock, GFP_KERNEL)) == NULL)

  		return -ENOBUFS;
  
  	sk->sk_protocol = protocol;
  
  	return 0;
  }
  
  
  static int
  dn_release(struct socket *sock)
  {
  	struct sock *sk = sock->sk;
  
  	if (sk) {
  		sock_orphan(sk);
  		sock_hold(sk);
  		lock_sock(sk);
  		dn_destroy_sock(sk);
  		release_sock(sk);
  		sock_put(sk);
  	}

  	return 0;

  }
  
  static int dn_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
  {
  	struct sock *sk = sock->sk;
  	struct dn_scp *scp = DN_SK(sk);
  	struct sockaddr_dn *saddr = (struct sockaddr_dn *)uaddr;

  	struct net_device *dev, *ldev;

  	int rv;
  
  	if (addr_len != sizeof(struct sockaddr_dn))
  		return -EINVAL;
  
  	if (saddr->sdn_family != AF_DECnet)
  		return -EINVAL;
  
  	if (dn_ntohs(saddr->sdn_nodeaddrl) && (dn_ntohs(saddr->sdn_nodeaddrl) != 2))
  		return -EINVAL;
  
  	if (dn_ntohs(saddr->sdn_objnamel) > DN_MAXOBJL)
  		return -EINVAL;
  
  	if (saddr->sdn_flags & ~SDF_WILD)
  		return -EINVAL;

  	if (!capable(CAP_NET_BIND_SERVICE) && (saddr->sdn_objnum ||
  	    (saddr->sdn_flags & SDF_WILD)))
  		return -EACCES;

  
  	if (!(saddr->sdn_flags & SDF_WILD)) {
  		if (dn_ntohs(saddr->sdn_nodeaddrl)) {
  			read_lock(&dev_base_lock);

  			ldev = NULL;

  			for_each_netdev(&init_net, dev) {

  				if (!dev->dn_ptr)
  					continue;

  				if (dn_dev_islocal(dev, dn_saddr2dn(saddr))) {
  					ldev = dev;

  					break;

  				}

  			}
  			read_unlock(&dev_base_lock);

  			if (ldev == NULL)

  				return -EADDRNOTAVAIL;
  		}
  	}
  
  	rv = -EINVAL;
  	lock_sock(sk);
  	if (sock_flag(sk, SOCK_ZAPPED)) {
  		memcpy(&scp->addr, saddr, addr_len);
  		sock_reset_flag(sk, SOCK_ZAPPED);
  
  		rv = dn_hash_sock(sk);
  		if (rv)
  			sock_set_flag(sk, SOCK_ZAPPED);
  	}
  	release_sock(sk);

  	return rv;

  }
  
  
  static int dn_auto_bind(struct socket *sock)
  {
  	struct sock *sk = sock->sk;
  	struct dn_scp *scp = DN_SK(sk);
  	int rv;
  
  	sock_reset_flag(sk, SOCK_ZAPPED);
  
  	scp->addr.sdn_flags  = 0;
  	scp->addr.sdn_objnum = 0;
  
  	/*
  	 * This stuff is to keep compatibility with Eduardo's
  	 * patch. I hope I can dispense with it shortly...
  	 */
  	if ((scp->accessdata.acc_accl != 0) &&
  		(scp->accessdata.acc_accl <= 12)) {

  		scp->addr.sdn_objnamel = dn_htons(scp->accessdata.acc_accl);
  		memcpy(scp->addr.sdn_objname, scp->accessdata.acc_acc, dn_ntohs(scp->addr.sdn_objnamel));
  
  		scp->accessdata.acc_accl = 0;
  		memset(scp->accessdata.acc_acc, 0, 40);
  	}
  	/* End of compatibility stuff */
  
  	scp->addr.sdn_add.a_len = dn_htons(2);

  	rv = dn_dev_bind_default((__le16 *)scp->addr.sdn_add.a_addr);

  	if (rv == 0) {
  		rv = dn_hash_sock(sk);
  		if (rv)
  			sock_set_flag(sk, SOCK_ZAPPED);
  	}
  
  	return rv;
  }

  static int dn_confirm_accept(struct sock *sk, long *timeo, gfp_t allocation)

  {
  	struct dn_scp *scp = DN_SK(sk);
  	DEFINE_WAIT(wait);
  	int err;
  
  	if (scp->state != DN_CR)
  		return -EINVAL;
  
  	scp->state = DN_CC;
  	scp->segsize_loc = dst_metric(__sk_dst_get(sk), RTAX_ADVMSS);
  	dn_send_conn_conf(sk, allocation);
  
  	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
  	for(;;) {
  		release_sock(sk);
  		if (scp->state == DN_CC)
  			*timeo = schedule_timeout(*timeo);
  		lock_sock(sk);
  		err = 0;
  		if (scp->state == DN_RUN)
  			break;
  		err = sock_error(sk);
  		if (err)
  			break;
  		err = sock_intr_errno(*timeo);
  		if (signal_pending(current))
  			break;
  		err = -EAGAIN;
  		if (!*timeo)
  			break;
  		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
  	}
  	finish_wait(sk->sk_sleep, &wait);
  	if (err == 0) {
  		sk->sk_socket->state = SS_CONNECTED;
  	} else if (scp->state != DN_CC) {
  		sk->sk_socket->state = SS_UNCONNECTED;
  	}
  	return err;
  }
  
  static int dn_wait_run(struct sock *sk, long *timeo)
  {
  	struct dn_scp *scp = DN_SK(sk);
  	DEFINE_WAIT(wait);
  	int err = 0;
  
  	if (scp->state == DN_RUN)
  		goto out;
  
  	if (!*timeo)
  		return -EALREADY;
  
  	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
  	for(;;) {
  		release_sock(sk);
  		if (scp->state == DN_CI || scp->state == DN_CC)
  			*timeo = schedule_timeout(*timeo);
  		lock_sock(sk);
  		err = 0;
  		if (scp->state == DN_RUN)
  			break;
  		err = sock_error(sk);
  		if (err)
  			break;
  		err = sock_intr_errno(*timeo);
  		if (signal_pending(current))
  			break;
  		err = -ETIMEDOUT;
  		if (!*timeo)
  			break;
  		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
  	}
  	finish_wait(sk->sk_sleep, &wait);
  out:
  	if (err == 0) {
  		sk->sk_socket->state = SS_CONNECTED;
  	} else if (scp->state != DN_CI && scp->state != DN_CC) {
  		sk->sk_socket->state = SS_UNCONNECTED;
  	}
  	return err;
  }
  
  static int __dn_connect(struct sock *sk, struct sockaddr_dn *addr, int addrlen, long *timeo, int flags)
  {
  	struct socket *sock = sk->sk_socket;
  	struct dn_scp *scp = DN_SK(sk);
  	int err = -EISCONN;
  	struct flowi fl;
  
  	if (sock->state == SS_CONNECTED)
  		goto out;
  
  	if (sock->state == SS_CONNECTING) {
  		err = 0;
  		if (scp->state == DN_RUN) {
  			sock->state = SS_CONNECTED;
  			goto out;
  		}
  		err = -ECONNREFUSED;
  		if (scp->state != DN_CI && scp->state != DN_CC) {
  			sock->state = SS_UNCONNECTED;
  			goto out;
  		}
  		return dn_wait_run(sk, timeo);
  	}
  
  	err = -EINVAL;
  	if (scp->state != DN_O)
  		goto out;
  
  	if (addr == NULL || addrlen != sizeof(struct sockaddr_dn))
  		goto out;
  	if (addr->sdn_family != AF_DECnet)
  		goto out;
  	if (addr->sdn_flags & SDF_WILD)
  		goto out;
  
  	if (sock_flag(sk, SOCK_ZAPPED)) {
  		err = dn_auto_bind(sk->sk_socket);
  		if (err)
  			goto out;
  	}
  
  	memcpy(&scp->peer, addr, sizeof(struct sockaddr_dn));
  
  	err = -EHOSTUNREACH;
  	memset(&fl, 0, sizeof(fl));
  	fl.oif = sk->sk_bound_dev_if;
  	fl.fld_dst = dn_saddr2dn(&scp->peer);
  	fl.fld_src = dn_saddr2dn(&scp->addr);
  	dn_sk_ports_copy(&fl, scp);
  	fl.proto = DNPROTO_NSP;
  	if (dn_route_output_sock(&sk->sk_dst_cache, &fl, sk, flags) < 0)
  		goto out;
  	sk->sk_route_caps = sk->sk_dst_cache->dev->features;
  	sock->state = SS_CONNECTING;
  	scp->state = DN_CI;
  	scp->segsize_loc = dst_metric(sk->sk_dst_cache, RTAX_ADVMSS);
  
  	dn_nsp_send_conninit(sk, NSP_CI);
  	err = -EINPROGRESS;
  	if (*timeo) {
  		err = dn_wait_run(sk, timeo);
  	}
  out:
  	return err;
  }
  
  static int dn_connect(struct socket *sock, struct sockaddr *uaddr, int addrlen, int flags)
  {
  	struct sockaddr_dn *addr = (struct sockaddr_dn *)uaddr;
  	struct sock *sk = sock->sk;
  	int err;
  	long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
  
  	lock_sock(sk);
  	err = __dn_connect(sk, addr, addrlen, &timeo, 0);
  	release_sock(sk);
  
  	return err;
  }
  
  static inline int dn_check_state(struct sock *sk, struct sockaddr_dn *addr, int addrlen, long *timeo, int flags)
  {
  	struct dn_scp *scp = DN_SK(sk);
  
  	switch(scp->state) {
  		case DN_RUN:
  			return 0;
  		case DN_CR:
  			return dn_confirm_accept(sk, timeo, sk->sk_allocation);
  		case DN_CI:
  		case DN_CC:
  			return dn_wait_run(sk, timeo);
  		case DN_O:
  			return __dn_connect(sk, addr, addrlen, timeo, flags);
  	}
  
  	return -EINVAL;
  }
  
  
  static void dn_access_copy(struct sk_buff *skb, struct accessdata_dn *acc)
  {

  	unsigned char *ptr = skb->data;

  	acc->acc_userl = *ptr++;
  	memcpy(&acc->acc_user, ptr, acc->acc_userl);
  	ptr += acc->acc_userl;

  	acc->acc_passl = *ptr++;
  	memcpy(&acc->acc_pass, ptr, acc->acc_passl);
  	ptr += acc->acc_passl;

  	acc->acc_accl = *ptr++;
  	memcpy(&acc->acc_acc, ptr, acc->acc_accl);

  	skb_pull(skb, acc->acc_accl + acc->acc_passl + acc->acc_userl + 3);

  
  }
  
  static void dn_user_copy(struct sk_buff *skb, struct optdata_dn *opt)
  {

  	unsigned char *ptr = skb->data;
  	u16 len = *ptr++; /* yes, it's 8bit on the wire */
  
  	BUG_ON(len > 16); /* we've checked the contents earlier */
  	opt->opt_optl   = dn_htons(len);
  	opt->opt_status = 0;
  	memcpy(opt->opt_data, ptr, len);
  	skb_pull(skb, len + 1);

  }
  
  static struct sk_buff *dn_wait_for_connect(struct sock *sk, long *timeo)
  {
  	DEFINE_WAIT(wait);
  	struct sk_buff *skb = NULL;
  	int err = 0;
  
  	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
  	for(;;) {
  		release_sock(sk);
  		skb = skb_dequeue(&sk->sk_receive_queue);
  		if (skb == NULL) {
  			*timeo = schedule_timeout(*timeo);
  			skb = skb_dequeue(&sk->sk_receive_queue);
  		}
  		lock_sock(sk);
  		if (skb != NULL)
  			break;
  		err = -EINVAL;
  		if (sk->sk_state != TCP_LISTEN)
  			break;
  		err = sock_intr_errno(*timeo);
  		if (signal_pending(current))
  			break;
  		err = -EAGAIN;
  		if (!*timeo)
  			break;
  		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
  	}
  	finish_wait(sk->sk_sleep, &wait);
  
  	return skb == NULL ? ERR_PTR(err) : skb;
  }
  
  static int dn_accept(struct socket *sock, struct socket *newsock, int flags)
  {
  	struct sock *sk = sock->sk, *newsk;
  	struct sk_buff *skb = NULL;
  	struct dn_skb_cb *cb;
  	unsigned char menuver;
  	int err = 0;
  	unsigned char type;
  	long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
  
  	lock_sock(sk);

  	if (sk->sk_state != TCP_LISTEN || DN_SK(sk)->state != DN_O) {

  		release_sock(sk);
  		return -EINVAL;
  	}
  
  	skb = skb_dequeue(&sk->sk_receive_queue);
  	if (skb == NULL) {
  		skb = dn_wait_for_connect(sk, &timeo);
  		if (IS_ERR(skb)) {
  			release_sock(sk);
  			return PTR_ERR(skb);
  		}
  	}
  
  	cb = DN_SKB_CB(skb);
  	sk->sk_ack_backlog--;

  	newsk = dn_alloc_sock(sock_net(sk), newsock, sk->sk_allocation);

  	if (newsk == NULL) {
  		release_sock(sk);
  		kfree_skb(skb);
  		return -ENOBUFS;
  	}
  	release_sock(sk);
  
  	dst_release(xchg(&newsk->sk_dst_cache, skb->dst));
  	skb->dst = NULL;

  	DN_SK(newsk)->state        = DN_CR;

  	DN_SK(newsk)->addrrem      = cb->src_port;
  	DN_SK(newsk)->services_rem = cb->services;
  	DN_SK(newsk)->info_rem     = cb->info;
  	DN_SK(newsk)->segsize_rem  = cb->segsize;
  	DN_SK(newsk)->accept_mode  = DN_SK(sk)->accept_mode;

  	if (DN_SK(newsk)->segsize_rem < 230)
  		DN_SK(newsk)->segsize_rem = 230;
  
  	if ((DN_SK(newsk)->services_rem & NSP_FC_MASK) == NSP_FC_NONE)
  		DN_SK(newsk)->max_window = decnet_no_fc_max_cwnd;
  
  	newsk->sk_state  = TCP_LISTEN;
  	memcpy(&(DN_SK(newsk)->addr), &(DN_SK(sk)->addr), sizeof(struct sockaddr_dn));
  
  	/*
  	 * If we are listening on a wild socket, we don't want
  	 * the newly created socket on the wrong hash queue.
  	 */
  	DN_SK(newsk)->addr.sdn_flags &= ~SDF_WILD;
  
  	skb_pull(skb, dn_username2sockaddr(skb->data, skb->len, &(DN_SK(newsk)->addr), &type));
  	skb_pull(skb, dn_username2sockaddr(skb->data, skb->len, &(DN_SK(newsk)->peer), &type));

  	*(__le16 *)(DN_SK(newsk)->peer.sdn_add.a_addr) = cb->src;
  	*(__le16 *)(DN_SK(newsk)->addr.sdn_add.a_addr) = cb->dst;

  
  	menuver = *skb->data;
  	skb_pull(skb, 1);
  
  	if (menuver & DN_MENUVER_ACC)
  		dn_access_copy(skb, &(DN_SK(newsk)->accessdata));
  
  	if (menuver & DN_MENUVER_USR)
  		dn_user_copy(skb, &(DN_SK(newsk)->conndata_in));
  
  	if (menuver & DN_MENUVER_PRX)
  		DN_SK(newsk)->peer.sdn_flags |= SDF_PROXY;
  
  	if (menuver & DN_MENUVER_UIC)
  		DN_SK(newsk)->peer.sdn_flags |= SDF_UICPROXY;
  
  	kfree_skb(skb);
  
  	memcpy(&(DN_SK(newsk)->conndata_out), &(DN_SK(sk)->conndata_out),
  		sizeof(struct optdata_dn));
  	memcpy(&(DN_SK(newsk)->discdata_out), &(DN_SK(sk)->discdata_out),
  		sizeof(struct optdata_dn));
  
  	lock_sock(newsk);
  	err = dn_hash_sock(newsk);
  	if (err == 0) {
  		sock_reset_flag(newsk, SOCK_ZAPPED);
  		dn_send_conn_ack(newsk);
  
  		/*

  		 * Here we use sk->sk_allocation since although the conn conf is
  		 * for the newsk, the context is the old socket.
  		 */

  		if (DN_SK(newsk)->accept_mode == ACC_IMMED)
  			err = dn_confirm_accept(newsk, &timeo,
  						sk->sk_allocation);
  	}
  	release_sock(newsk);

  	return err;

  }
  
  
  static int dn_getname(struct socket *sock, struct sockaddr *uaddr,int *uaddr_len,int peer)
  {
  	struct sockaddr_dn *sa = (struct sockaddr_dn *)uaddr;
  	struct sock *sk = sock->sk;
  	struct dn_scp *scp = DN_SK(sk);
  
  	*uaddr_len = sizeof(struct sockaddr_dn);
  
  	lock_sock(sk);
  
  	if (peer) {

  		if ((sock->state != SS_CONNECTED &&
  		     sock->state != SS_CONNECTING) &&

  		    scp->accept_mode == ACC_IMMED) {

  			release_sock(sk);

  			return -ENOTCONN;

  		}

  
  		memcpy(sa, &scp->peer, sizeof(struct sockaddr_dn));
  	} else {
  		memcpy(sa, &scp->addr, sizeof(struct sockaddr_dn));
  	}
  
  	release_sock(sk);

  	return 0;

  }
  
  
  static unsigned int dn_poll(struct file *file, struct socket *sock, poll_table  *wait)
  {
  	struct sock *sk = sock->sk;
  	struct dn_scp *scp = DN_SK(sk);
  	int mask = datagram_poll(file, sock, wait);

  	if (!skb_queue_empty(&scp->other_receive_queue))

  		mask |= POLLRDBAND;
  
  	return mask;
  }
  
  static int dn_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
  {
  	struct sock *sk = sock->sk;
  	struct dn_scp *scp = DN_SK(sk);
  	int err = -EOPNOTSUPP;
  	long amount = 0;
  	struct sk_buff *skb;
  	int val;
  
  	switch(cmd)
  	{
  	case SIOCGIFADDR:
  	case SIOCSIFADDR:
  		return dn_dev_ioctl(cmd, (void __user *)arg);
  
  	case SIOCATMARK:
  		lock_sock(sk);

  		val = !skb_queue_empty(&scp->other_receive_queue);

  		if (scp->state != DN_RUN)
  			val = -ENOTCONN;
  		release_sock(sk);
  		return val;
  
  	case TIOCOUTQ:
  		amount = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
  		if (amount < 0)
  			amount = 0;
  		err = put_user(amount, (int __user *)arg);
  		break;
  
  	case TIOCINQ:
  		lock_sock(sk);
  		if ((skb = skb_peek(&scp->other_receive_queue)) != NULL) {
  			amount = skb->len;
  		} else {
  			struct sk_buff *skb = sk->sk_receive_queue.next;
  			for(;;) {
  				if (skb ==
  				    (struct sk_buff *)&sk->sk_receive_queue)
  					break;
  				amount += skb->len;
  				skb = skb->next;
  			}
  		}
  		release_sock(sk);
  		err = put_user(amount, (int __user *)arg);
  		break;
  
  	default:

  		err = -ENOIOCTLCMD;

  		break;
  	}
  
  	return err;
  }
  
  static int dn_listen(struct socket *sock, int backlog)
  {
  	struct sock *sk = sock->sk;
  	int err = -EINVAL;
  
  	lock_sock(sk);
  
  	if (sock_flag(sk, SOCK_ZAPPED))
  		goto out;
  
  	if ((DN_SK(sk)->state != DN_O) || (sk->sk_state == TCP_LISTEN))
  		goto out;
  
  	sk->sk_max_ack_backlog = backlog;
  	sk->sk_ack_backlog     = 0;
  	sk->sk_state           = TCP_LISTEN;
  	err                 = 0;
  	dn_rehash_sock(sk);
  
  out:
  	release_sock(sk);

  	return err;

  }
  
  
  static int dn_shutdown(struct socket *sock, int how)
  {
  	struct sock *sk = sock->sk;
  	struct dn_scp *scp = DN_SK(sk);
  	int err = -ENOTCONN;
  
  	lock_sock(sk);
  
  	if (sock->state == SS_UNCONNECTED)
  		goto out;
  
  	err = 0;
  	if (sock->state == SS_DISCONNECTING)
  		goto out;
  
  	err = -EINVAL;
  	if (scp->state == DN_O)
  		goto out;
  
  	if (how != SHUTDOWN_MASK)
  		goto out;
  
  	sk->sk_shutdown = how;
  	dn_destroy_sock(sk);
  	err = 0;
  
  out:
  	release_sock(sk);
  
  	return err;
  }
  
  static int dn_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen)
  {
  	struct sock *sk = sock->sk;
  	int err;
  
  	lock_sock(sk);
  	err = __dn_setsockopt(sock, level, optname, optval, optlen, 0);
  	release_sock(sk);
  
  	return err;
  }

  static int __dn_setsockopt(struct socket *sock, int level,int optname, char __user *optval, int optlen, int flags)

  {
  	struct	sock *sk = sock->sk;
  	struct dn_scp *scp = DN_SK(sk);
  	long timeo;
  	union {
  		struct optdata_dn opt;
  		struct accessdata_dn acc;
  		int mode;
  		unsigned long win;
  		int val;
  		unsigned char services;
  		unsigned char info;
  	} u;
  	int err;
  
  	if (optlen && !optval)
  		return -EINVAL;
  
  	if (optlen > sizeof(u))
  		return -EINVAL;
  
  	if (copy_from_user(&u, optval, optlen))
  		return -EFAULT;
  
  	switch(optname) {
  		case DSO_CONDATA:

  			if (sock->state == SS_CONNECTED)

  				return -EISCONN;
  			if ((scp->state != DN_O) && (scp->state != DN_CR))
  				return -EINVAL;
  
  			if (optlen != sizeof(struct optdata_dn))
  				return -EINVAL;

  			if (dn_ntohs(u.opt.opt_optl) > 16)

  				return -EINVAL;
  
  			memcpy(&scp->conndata_out, &u.opt, optlen);
  			break;
  
  		case DSO_DISDATA:

  			if (sock->state != SS_CONNECTED && scp->accept_mode == ACC_IMMED)

  				return -ENOTCONN;
  
  			if (optlen != sizeof(struct optdata_dn))
  				return -EINVAL;

  			if (dn_ntohs(u.opt.opt_optl) > 16)

  				return -EINVAL;
  
  			memcpy(&scp->discdata_out, &u.opt, optlen);
  			break;
  
  		case DSO_CONACCESS:

  			if (sock->state == SS_CONNECTED)

  				return -EISCONN;
  			if (scp->state != DN_O)
  				return -EINVAL;
  
  			if (optlen != sizeof(struct accessdata_dn))
  				return -EINVAL;
  
  			if ((u.acc.acc_accl > DN_MAXACCL) ||
  					(u.acc.acc_passl > DN_MAXACCL) ||
  					(u.acc.acc_userl > DN_MAXACCL))
  				return -EINVAL;
  
  			memcpy(&scp->accessdata, &u.acc, optlen);
  			break;
  
  		case DSO_ACCEPTMODE:
  			if (sock->state == SS_CONNECTED)
  				return -EISCONN;
  			if (scp->state != DN_O)
  				return -EINVAL;
  
  			if (optlen != sizeof(int))
  				return -EINVAL;
  
  			if ((u.mode != ACC_IMMED) && (u.mode != ACC_DEFER))
  				return -EINVAL;
  
  			scp->accept_mode = (unsigned char)u.mode;
  			break;
  
  		case DSO_CONACCEPT:
  
  			if (scp->state != DN_CR)
  				return -EINVAL;
  			timeo = sock_rcvtimeo(sk, 0);
  			err = dn_confirm_accept(sk, &timeo, sk->sk_allocation);
  			return err;
  
  		case DSO_CONREJECT:
  
  			if (scp->state != DN_CR)
  				return -EINVAL;
  
  			scp->state = DN_DR;
  			sk->sk_shutdown = SHUTDOWN_MASK;
  			dn_nsp_send_disc(sk, 0x38, 0, sk->sk_allocation);
  			break;
  
  		default:
  #ifdef CONFIG_NETFILTER
  		return nf_setsockopt(sk, PF_DECnet, optname, optval, optlen);
  #endif
  		case DSO_LINKINFO:
  		case DSO_STREAM:
  		case DSO_SEQPACKET:
  			return -ENOPROTOOPT;
  
  		case DSO_MAXWINDOW:
  			if (optlen != sizeof(unsigned long))
  				return -EINVAL;
  			if (u.win > NSP_MAX_WINDOW)
  				u.win = NSP_MAX_WINDOW;
  			if (u.win == 0)
  				return -EINVAL;
  			scp->max_window = u.win;
  			if (scp->snd_window > u.win)
  				scp->snd_window = u.win;
  			break;
  
  		case DSO_NODELAY:
  			if (optlen != sizeof(int))
  				return -EINVAL;
  			if (scp->nonagle == 2)
  				return -EINVAL;
  			scp->nonagle = (u.val == 0) ? 0 : 1;
  			/* if (scp->nonagle == 1) { Push pending frames } */
  			break;
  
  		case DSO_CORK:
  			if (optlen != sizeof(int))
  				return -EINVAL;
  			if (scp->nonagle == 1)
  				return -EINVAL;
  			scp->nonagle = (u.val == 0) ? 0 : 2;
  			/* if (scp->nonagle == 0) { Push pending frames } */
  			break;
  
  		case DSO_SERVICES:
  			if (optlen != sizeof(unsigned char))
  				return -EINVAL;
  			if ((u.services & ~NSP_FC_MASK) != 0x01)
  				return -EINVAL;
  			if ((u.services & NSP_FC_MASK) == NSP_FC_MASK)
  				return -EINVAL;
  			scp->services_loc = u.services;
  			break;
  
  		case DSO_INFO:
  			if (optlen != sizeof(unsigned char))
  				return -EINVAL;
  			if (u.info & 0xfc)
  				return -EINVAL;
  			scp->info_loc = u.info;
  			break;
  	}
  
  	return 0;
  }
  
  static int dn_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
  {
  	struct sock *sk = sock->sk;
  	int err;
  
  	lock_sock(sk);
  	err = __dn_getsockopt(sock, level, optname, optval, optlen, 0);
  	release_sock(sk);
  
  	return err;
  }
  
  static int __dn_getsockopt(struct socket *sock, int level,int optname, char __user *optval,int __user *optlen, int flags)
  {
  	struct	sock *sk = sock->sk;
  	struct dn_scp *scp = DN_SK(sk);
  	struct linkinfo_dn link;
  	unsigned int r_len;
  	void *r_data = NULL;
  	unsigned int val;
  
  	if(get_user(r_len , optlen))
  		return -EFAULT;

  	switch(optname) {
  		case DSO_CONDATA:
  			if (r_len > sizeof(struct optdata_dn))
  				r_len = sizeof(struct optdata_dn);
  			r_data = &scp->conndata_in;
  			break;
  
  		case DSO_DISDATA:
  			if (r_len > sizeof(struct optdata_dn))
  				r_len = sizeof(struct optdata_dn);
  			r_data = &scp->discdata_in;
  			break;
  
  		case DSO_CONACCESS:
  			if (r_len > sizeof(struct accessdata_dn))
  				r_len = sizeof(struct accessdata_dn);
  			r_data = &scp->accessdata;
  			break;
  
  		case DSO_ACCEPTMODE:
  			if (r_len > sizeof(unsigned char))
  				r_len = sizeof(unsigned char);
  			r_data = &scp->accept_mode;
  			break;
  
  		case DSO_LINKINFO:
  			if (r_len > sizeof(struct linkinfo_dn))
  				r_len = sizeof(struct linkinfo_dn);
  
  			switch(sock->state) {
  				case SS_CONNECTING:
  					link.idn_linkstate = LL_CONNECTING;
  					break;
  				case SS_DISCONNECTING:
  					link.idn_linkstate = LL_DISCONNECTING;
  					break;
  				case SS_CONNECTED:
  					link.idn_linkstate = LL_RUNNING;
  					break;
  				default:
  					link.idn_linkstate = LL_INACTIVE;
  			}
  
  			link.idn_segsize = scp->segsize_rem;
  			r_data = &link;
  			break;
  
  		default:
  #ifdef CONFIG_NETFILTER
  		{
  			int val, len;

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

  
  			val = nf_getsockopt(sk, PF_DECnet, optname,

  							optval, &len);
  			if (val >= 0)
  				val = put_user(len, optlen);
  			return val;
  		}
  #endif
  		case DSO_STREAM:
  		case DSO_SEQPACKET:
  		case DSO_CONACCEPT:
  		case DSO_CONREJECT:

  			return -ENOPROTOOPT;

  
  		case DSO_MAXWINDOW:
  			if (r_len > sizeof(unsigned long))
  				r_len = sizeof(unsigned long);
  			r_data = &scp->max_window;
  			break;
  
  		case DSO_NODELAY:
  			if (r_len > sizeof(int))
  				r_len = sizeof(int);
  			val = (scp->nonagle == 1);
  			r_data = &val;
  			break;
  
  		case DSO_CORK:
  			if (r_len > sizeof(int))
  				r_len = sizeof(int);
  			val = (scp->nonagle == 2);
  			r_data = &val;
  			break;
  
  		case DSO_SERVICES:
  			if (r_len > sizeof(unsigned char))
  				r_len = sizeof(unsigned char);
  			r_data = &scp->services_rem;
  			break;
  
  		case DSO_INFO:
  			if (r_len > sizeof(unsigned char))
  				r_len = sizeof(unsigned char);
  			r_data = &scp->info_rem;
  			break;
  	}
  
  	if (r_data) {
  		if (copy_to_user(optval, r_data, r_len))
  			return -EFAULT;
  		if (put_user(r_len, optlen))
  			return -EFAULT;
  	}
  
  	return 0;
  }
  
  
  static int dn_data_ready(struct sock *sk, struct sk_buff_head *q, int flags, int target)
  {
  	struct sk_buff *skb = q->next;
  	int len = 0;
  
  	if (flags & MSG_OOB)

  		return !skb_queue_empty(q) ? 1 : 0;

  
  	while(skb != (struct sk_buff *)q) {
  		struct dn_skb_cb *cb = DN_SKB_CB(skb);
  		len += skb->len;
  
  		if (cb->nsp_flags & 0x40) {
  			/* SOCK_SEQPACKET reads to EOM */
  			if (sk->sk_type == SOCK_SEQPACKET)
  				return 1;
  			/* so does SOCK_STREAM unless WAITALL is specified */
  			if (!(flags & MSG_WAITALL))
  				return 1;
  		}
  
  		/* minimum data length for read exceeded */
  		if (len >= target)
  			return 1;
  
  		skb = skb->next;
  	}
  
  	return 0;
  }
  
  
  static int dn_recvmsg(struct kiocb *iocb, struct socket *sock,
  	struct msghdr *msg, size_t size, int flags)
  {
  	struct sock *sk = sock->sk;
  	struct dn_scp *scp = DN_SK(sk);
  	struct sk_buff_head *queue = &sk->sk_receive_queue;
  	size_t target = size > 1 ? 1 : 0;
  	size_t copied = 0;
  	int rv = 0;
  	struct sk_buff *skb, *nskb;
  	struct dn_skb_cb *cb = NULL;
  	unsigned char eor = 0;
  	long timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
  
  	lock_sock(sk);
  
  	if (sock_flag(sk, SOCK_ZAPPED)) {
  		rv = -EADDRNOTAVAIL;
  		goto out;
  	}

  	if (sk->sk_shutdown & RCV_SHUTDOWN) {

  		rv = 0;

  		goto out;
  	}

  	rv = dn_check_state(sk, NULL, 0, &timeo, flags);
  	if (rv)
  		goto out;

  	if (flags & ~(MSG_CMSG_COMPAT|MSG_PEEK|MSG_OOB|MSG_WAITALL|MSG_DONTWAIT|MSG_NOSIGNAL)) {

  		rv = -EOPNOTSUPP;
  		goto out;
  	}
  
  	if (flags & MSG_OOB)
  		queue = &scp->other_receive_queue;
  
  	if (flags & MSG_WAITALL)
  		target = size;
  
  
  	/*
  	 * See if there is data ready to read, sleep if there isn't
  	 */
  	for(;;) {

  		DEFINE_WAIT(wait);

  		if (sk->sk_err)
  			goto out;

  		if (!skb_queue_empty(&scp->other_receive_queue)) {

  			if (!(flags & MSG_OOB)) {
  				msg->msg_flags |= MSG_OOB;
  				if (!scp->other_report) {
  					scp->other_report = 1;
  					goto out;
  				}
  			}
  		}

  		if (scp->state != DN_RUN)
  			goto out;
  
  		if (signal_pending(current)) {
  			rv = sock_intr_errno(timeo);
  			goto out;
  		}
  
  		if (dn_data_ready(sk, queue, flags, target))
  			break;
  
  		if (flags & MSG_DONTWAIT) {
  			rv = -EWOULDBLOCK;
  			goto out;
  		}

  		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
  		set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
  		sk_wait_event(sk, &timeo, dn_data_ready(sk, queue, flags, target));
  		clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
  		finish_wait(sk->sk_sleep, &wait);

  	}
  
  	for(skb = queue->next; skb != (struct sk_buff *)queue; skb = nskb) {
  		unsigned int chunk = skb->len;
  		cb = DN_SKB_CB(skb);
  
  		if ((chunk + copied) > size)
  			chunk = size - copied;
  
  		if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
  			rv = -EFAULT;
  			break;
  		}
  		copied += chunk;
  
  		if (!(flags & MSG_PEEK))
  			skb_pull(skb, chunk);
  
  		eor = cb->nsp_flags & 0x40;
  		nskb = skb->next;
  
  		if (skb->len == 0) {

  			skb_unlink(skb, queue);

  			kfree_skb(skb);

  			/*

  			 * N.B. Don't refer to skb or cb after this point
  			 * in loop.
  			 */
  			if ((scp->flowloc_sw == DN_DONTSEND) && !dn_congested(sk)) {
  				scp->flowloc_sw = DN_SEND;
  				dn_nsp_send_link(sk, DN_SEND, 0);
  			}
  		}

  		if (eor) {

  			if (sk->sk_type == SOCK_SEQPACKET)
  				break;
  			if (!(flags & MSG_WAITALL))
  				break;
  		}
  
  		if (flags & MSG_OOB)
  			break;
  
  		if (copied >= target)
  			break;
  	}
  
  	rv = copied;
  
  
  	if (eor && (sk->sk_type == SOCK_SEQPACKET))
  		msg->msg_flags |= MSG_EOR;
  
  out:
  	if (rv == 0)
  		rv = (flags & MSG_PEEK) ? -sk->sk_err : sock_error(sk);
  
  	if ((rv >= 0) && msg->msg_name) {
  		memcpy(msg->msg_name, &scp->peer, sizeof(struct sockaddr_dn));
  		msg->msg_namelen = sizeof(struct sockaddr_dn);
  	}
  
  	release_sock(sk);
  
  	return rv;
  }
  
  
  static inline int dn_queue_too_long(struct dn_scp *scp, struct sk_buff_head *queue, int flags)
  {
  	unsigned char fctype = scp->services_rem & NSP_FC_MASK;
  	if (skb_queue_len(queue) >= scp->snd_window)
  		return 1;
  	if (fctype != NSP_FC_NONE) {
  		if (flags & MSG_OOB) {
  			if (scp->flowrem_oth == 0)
  				return 1;
  		} else {
  			if (scp->flowrem_dat == 0)
  				return 1;
  		}
  	}
  	return 0;
  }
  
  /*

   * The DECnet spec requires that the "routing layer" accepts packets which

   * are at least 230 bytes in size. This excludes any headers which the NSP
   * layer might add, so we always assume that we'll be using the maximal
   * length header on data packets. The variation in length is due to the
   * inclusion (or not) of the two 16 bit acknowledgement fields so it doesn't
   * make much practical difference.
   */
  unsigned dn_mss_from_pmtu(struct net_device *dev, int mtu)
  {
  	unsigned mss = 230 - DN_MAX_NSP_DATA_HEADER;
  	if (dev) {
  		struct dn_dev *dn_db = dev->dn_ptr;
  		mtu -= LL_RESERVED_SPACE(dev);
  		if (dn_db->use_long)
  			mtu -= 21;
  		else
  			mtu -= 6;
  		mtu -= DN_MAX_NSP_DATA_HEADER;
  	} else {
  		/*
  		 * 21 = long header, 16 = guess at MAC header length
  		 */
  		mtu -= (21 + DN_MAX_NSP_DATA_HEADER + 16);
  	}
  	if (mtu > mss)
  		mss = mtu;
  	return mss;
  }
  
  static inline unsigned int dn_current_mss(struct sock *sk, int flags)
  {
  	struct dst_entry *dst = __sk_dst_get(sk);
  	struct dn_scp *scp = DN_SK(sk);
  	int mss_now = min_t(int, scp->segsize_loc, scp->segsize_rem);
  
  	/* Other data messages are limited to 16 bytes per packet */
  	if (flags & MSG_OOB)
  		return 16;
  
  	/* This works out the maximum size of segment we can send out */
  	if (dst) {
  		u32 mtu = dst_mtu(dst);
  		mss_now = min_t(int, dn_mss_from_pmtu(dst->dev, mtu), mss_now);
  	}
  
  	return mss_now;
  }

  /*

   * N.B. We get the timeout wrong here, but then we always did get it
   * wrong before and this is another step along the road to correcting
   * it. It ought to get updated each time we pass through the routine,
   * but in practise it probably doesn't matter too much for now.
   */
  static inline struct sk_buff *dn_alloc_send_pskb(struct sock *sk,
  			      unsigned long datalen, int noblock,
  			      int *errcode)
  {
  	struct sk_buff *skb = sock_alloc_send_skb(sk, datalen,
  						   noblock, errcode);
  	if (skb) {

  		skb->protocol = htons(ETH_P_DNA_RT);

  		skb->pkt_type = PACKET_OUTGOING;
  	}
  	return skb;
  }

  static int dn_sendmsg(struct kiocb *iocb, struct socket *sock,

  		      struct msghdr *msg, size_t size)

  {
  	struct sock *sk = sock->sk;
  	struct dn_scp *scp = DN_SK(sk);
  	size_t mss;
  	struct sk_buff_head *queue = &scp->data_xmit_queue;
  	int flags = msg->msg_flags;
  	int err = 0;
  	size_t sent = 0;
  	int addr_len = msg->msg_namelen;
  	struct sockaddr_dn *addr = (struct sockaddr_dn *)msg->msg_name;
  	struct sk_buff *skb = NULL;
  	struct dn_skb_cb *cb;
  	size_t len;
  	unsigned char fctype;

  	long timeo;

  
  	if (flags & ~(MSG_TRYHARD|MSG_OOB|MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|MSG_MORE|MSG_CMSG_COMPAT))
  		return -EOPNOTSUPP;
  
  	if (addr_len && (addr_len != sizeof(struct sockaddr_dn)))
  		return -EINVAL;

  	lock_sock(sk);
  	timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);

  	/*
  	 * The only difference between stream sockets and sequenced packet
  	 * sockets is that the stream sockets always behave as if MSG_EOR
  	 * has been set.
  	 */
  	if (sock->type == SOCK_STREAM) {

  		if (flags & MSG_EOR) {
  			err = -EINVAL;
  			goto out;
  		}

  		flags |= MSG_EOR;
  	}

  
  	err = dn_check_state(sk, addr, addr_len, &timeo, flags);
  	if (err)
  		goto out_err;
  
  	if (sk->sk_shutdown & SEND_SHUTDOWN) {
  		err = -EPIPE;

  		if (!(flags & MSG_NOSIGNAL))
  			send_sig(SIGPIPE, current, 0);

  		goto out_err;
  	}
  
  	if ((flags & MSG_TRYHARD) && sk->sk_dst_cache)
  		dst_negative_advice(&sk->sk_dst_cache);
  
  	mss = scp->segsize_rem;
  	fctype = scp->services_rem & NSP_FC_MASK;
  
  	mss = dn_current_mss(sk, flags);
  
  	if (flags & MSG_OOB) {
  		queue = &scp->other_xmit_queue;
  		if (size > mss) {
  			err = -EMSGSIZE;
  			goto out;
  		}
  	}
  
  	scp->persist_fxn = dn_nsp_xmit_timeout;
  
  	while(sent < size) {
  		err = sock_error(sk);
  		if (err)
  			goto out;
  
  		if (signal_pending(current)) {
  			err = sock_intr_errno(timeo);
  			goto out;
  		}
  
  		/*
  		 * Calculate size that we wish to send.
  		 */
  		len = size - sent;
  
  		if (len > mss)
  			len = mss;
  
  		/*
  		 * Wait for queue size to go down below the window
  		 * size.
  		 */
  		if (dn_queue_too_long(scp, queue, flags)) {

  			DEFINE_WAIT(wait);

  			if (flags & MSG_DONTWAIT) {
  				err = -EWOULDBLOCK;
  				goto out;
  			}

  			prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
  			set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
  			sk_wait_event(sk, &timeo,
  				      !dn_queue_too_long(scp, queue, flags));
  			clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
  			finish_wait(sk->sk_sleep, &wait);

  			continue;
  		}
  
  		/*
  		 * Get a suitably sized skb.

  		 * 64 is a bit of a hack really, but its larger than any
  		 * link-layer headers and has served us well as a good
  		 * guess as to their real length.

  		 */

  		skb = dn_alloc_send_pskb(sk, len + 64 + DN_MAX_NSP_DATA_HEADER,
  					 flags & MSG_DONTWAIT, &err);

  
  		if (err)
  			break;
  
  		if (!skb)
  			continue;
  
  		cb = DN_SKB_CB(skb);

  		skb_reserve(skb, 64 + DN_MAX_NSP_DATA_HEADER);

  
  		if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
  			err = -EFAULT;
  			goto out;
  		}
  
  		if (flags & MSG_OOB) {
  			cb->nsp_flags = 0x30;
  			if (fctype != NSP_FC_NONE)
  				scp->flowrem_oth--;
  		} else {
  			cb->nsp_flags = 0x00;
  			if (scp->seg_total == 0)
  				cb->nsp_flags |= 0x20;
  
  			scp->seg_total += len;

  			if (((sent + len) == size) && (flags & MSG_EOR)) {
  				cb->nsp_flags |= 0x40;
  				scp->seg_total = 0;
  				if (fctype == NSP_FC_SCMC)
  					scp->flowrem_dat--;
  			}
  			if (fctype == NSP_FC_SRC)
  				scp->flowrem_dat--;
  		}
  
  		sent += len;
  		dn_nsp_queue_xmit(sk, skb, sk->sk_allocation, flags & MSG_OOB);
  		skb = NULL;
  
  		scp->persist = dn_nsp_persist(sk);
  
  	}
  out:
  
  	if (skb)
  		kfree_skb(skb);
  
  	release_sock(sk);
  
  	return sent ? sent : err;
  
  out_err:

  	err = sk_stream_error(sk, flags, err);

  	release_sock(sk);
  	return err;
  }
  
  static int dn_device_event(struct notifier_block *this, unsigned long event,
  			void *ptr)
  {
  	struct net_device *dev = (struct net_device *)ptr;

  	if (!net_eq(dev_net(dev), &init_net))

  		return NOTIFY_DONE;

  	switch(event) {
  		case NETDEV_UP:
  			dn_dev_up(dev);
  			break;
  		case NETDEV_DOWN:
  			dn_dev_down(dev);
  			break;
  		default:
  			break;
  	}
  
  	return NOTIFY_DONE;
  }
  
  static struct notifier_block dn_dev_notifier = {
  	.notifier_call = dn_device_event,
  };

  extern int dn_route_rcv(struct sk_buff *, struct net_device *, struct packet_type *, struct net_device *);

  
  static struct packet_type dn_dix_packet_type = {
  	.type =		__constant_htons(ETH_P_DNA_RT),
  	.dev =		NULL,		/* All devices */
  	.func =		dn_route_rcv,
  };
  
  #ifdef CONFIG_PROC_FS
  struct dn_iter_state {
  	int bucket;
  };
  
  static struct sock *dn_socket_get_first(struct seq_file *seq)
  {
  	struct dn_iter_state *state = seq->private;
  	struct sock *n = NULL;
  
  	for(state->bucket = 0;
  	    state->bucket < DN_SK_HASH_SIZE;
  	    ++state->bucket) {
  		n = sk_head(&dn_sk_hash[state->bucket]);
  		if (n)
  			break;
  	}
  
  	return n;
  }
  
  static struct sock *dn_socket_get_next(struct seq_file *seq,
  				       struct sock *n)
  {
  	struct dn_iter_state *state = seq->private;
  
  	n = sk_next(n);
  try_again:
  	if (n)
  		goto out;
  	if (++state->bucket >= DN_SK_HASH_SIZE)
  		goto out;
  	n = sk_head(&dn_sk_hash[state->bucket]);
  	goto try_again;
  out:
  	return n;
  }
  
  static struct sock *socket_get_idx(struct seq_file *seq, loff_t *pos)
  {
  	struct sock *sk = dn_socket_get_first(seq);
  
  	if (sk) {
  		while(*pos && (sk = dn_socket_get_next(seq, sk)))
  			--*pos;
  	}
  	return *pos ? NULL : sk;
  }
  
  static void *dn_socket_get_idx(struct seq_file *seq, loff_t pos)
  {
  	void *rc;
  	read_lock_bh(&dn_hash_lock);
  	rc = socket_get_idx(seq, &pos);
  	if (!rc) {
  		read_unlock_bh(&dn_hash_lock);
  	}
  	return rc;
  }
  
  static void *dn_socket_seq_start(struct seq_file *seq, loff_t *pos)
  {
  	return *pos ? dn_socket_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
  }
  
  static void *dn_socket_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  {
  	void *rc;
  
  	if (v == SEQ_START_TOKEN) {
  		rc = dn_socket_get_idx(seq, 0);
  		goto out;
  	}
  
  	rc = dn_socket_get_next(seq, v);
  	if (rc)
  		goto out;
  	read_unlock_bh(&dn_hash_lock);
  out:
  	++*pos;
  	return rc;
  }
  
  static void dn_socket_seq_stop(struct seq_file *seq, void *v)
  {
  	if (v && v != SEQ_START_TOKEN)
  		read_unlock_bh(&dn_hash_lock);
  }
  
  #define IS_NOT_PRINTABLE(x) ((x) < 32 || (x) > 126)
  
  static void dn_printable_object(struct sockaddr_dn *dn, unsigned char *buf)
  {
  	int i;

  	switch (dn_ntohs(dn->sdn_objnamel)) {
  		case 0:
  			sprintf(buf, "%d", dn->sdn_objnum);
  			break;
  		default:
  			for (i = 0; i < dn_ntohs(dn->sdn_objnamel); i++) {
  				buf[i] = dn->sdn_objname[i];
  				if (IS_NOT_PRINTABLE(buf[i]))
  					buf[i] = '.';
  			}
  			buf[i] = 0;

  	}

  }
  
  static char *dn_state2asc(unsigned char state)
  {
  	switch(state) {
  		case DN_O:
  			return "OPEN";
  		case DN_CR:
  			return "  CR";
  		case DN_DR:
  			return "  DR";
  		case DN_DRC:
  			return " DRC";
  		case DN_CC:
  			return "  CC";
  		case DN_CI:
  			return "  CI";
  		case DN_NR:
  			return "  NR";
  		case DN_NC:
  			return "  NC";
  		case DN_CD:
  			return "  CD";
  		case DN_RJ:
  			return "  RJ";
  		case DN_RUN:
  			return " RUN";
  		case DN_DI:
  			return "  DI";
  		case DN_DIC:
  			return " DIC";
  		case DN_DN:
  			return "  DN";
  		case DN_CL:
  			return "  CL";
  		case DN_CN:
  			return "  CN";
  	}
  
  	return "????";
  }
  
  static inline void dn_socket_format_entry(struct seq_file *seq, struct sock *sk)
  {
  	struct dn_scp *scp = DN_SK(sk);
  	char buf1[DN_ASCBUF_LEN];
  	char buf2[DN_ASCBUF_LEN];
  	char local_object[DN_MAXOBJL+3];
  	char remote_object[DN_MAXOBJL+3];
  
  	dn_printable_object(&scp->addr, local_object);
  	dn_printable_object(&scp->peer, remote_object);
  
  	seq_printf(seq,
  		   "%6s/%04X %04d:%04d %04d:%04d %01d %-16s "
  		   "%6s/%04X %04d:%04d %04d:%04d %01d %-16s %4s %s
  ",
  		   dn_addr2asc(dn_ntohs(dn_saddr2dn(&scp->addr)), buf1),
  		   scp->addrloc,
  		   scp->numdat,
  		   scp->numoth,
  		   scp->ackxmt_dat,
  		   scp->ackxmt_oth,
  		   scp->flowloc_sw,
  		   local_object,
  		   dn_addr2asc(dn_ntohs(dn_saddr2dn(&scp->peer)), buf2),
  		   scp->addrrem,
  		   scp->numdat_rcv,
  		   scp->numoth_rcv,
  		   scp->ackrcv_dat,
  		   scp->ackrcv_oth,
  		   scp->flowrem_sw,
  		   remote_object,
  		   dn_state2asc(scp->state),
  		   ((scp->accept_mode == ACC_IMMED) ? "IMMED" : "DEFER"));
  }
  
  static int dn_socket_seq_show(struct seq_file *seq, void *v)
  {
  	if (v == SEQ_START_TOKEN) {
  		seq_puts(seq, "Local                                              Remote
  ");
  	} else {
  		dn_socket_format_entry(seq, v);
  	}
  	return 0;
  }

  static const struct seq_operations dn_socket_seq_ops = {

  	.start	= dn_socket_seq_start,
  	.next	= dn_socket_seq_next,
  	.stop	= dn_socket_seq_stop,
  	.show	= dn_socket_seq_show,
  };
  
  static int dn_socket_seq_open(struct inode *inode, struct file *file)
  {

  	return seq_open_private(file, &dn_socket_seq_ops,
  			sizeof(struct dn_iter_state));

  }

  static const struct file_operations dn_socket_seq_fops = {

  	.owner		= THIS_MODULE,
  	.open		= dn_socket_seq_open,
  	.read		= seq_read,
  	.llseek		= seq_lseek,
  	.release	= seq_release_private,
  };
  #endif
  
  static struct net_proto_family	dn_family_ops = {
  	.family =	AF_DECnet,
  	.create =	dn_create,
  	.owner	=	THIS_MODULE,
  };

  static const struct proto_ops dn_proto_ops = {

  	.family =	AF_DECnet,
  	.owner =	THIS_MODULE,
  	.release =	dn_release,
  	.bind =		dn_bind,
  	.connect =	dn_connect,
  	.socketpair =	sock_no_socketpair,
  	.accept =	dn_accept,
  	.getname =	dn_getname,
  	.poll =		dn_poll,
  	.ioctl =	dn_ioctl,
  	.listen =	dn_listen,
  	.shutdown =	dn_shutdown,
  	.setsockopt =	dn_setsockopt,
  	.getsockopt =	dn_getsockopt,
  	.sendmsg =	dn_sendmsg,
  	.recvmsg =	dn_recvmsg,
  	.mmap =		sock_no_mmap,
  	.sendpage =	sock_no_sendpage,
  };
  
  void dn_register_sysctl(void);
  void dn_unregister_sysctl(void);
  
  MODULE_DESCRIPTION("The Linux DECnet Network Protocol");
  MODULE_AUTHOR("Linux DECnet Project Team");
  MODULE_LICENSE("GPL");
  MODULE_ALIAS_NETPROTO(PF_DECnet);
  
  static char banner[] __initdata = KERN_INFO "NET4: DECnet for Linux: V.2.5.68s (C) 1995-2003 Linux DECnet Project Team
  ";
  
  static int __init decnet_init(void)
  {
  	int rc;

  	printk(banner);

  
  	rc = proto_register(&dn_proto, 1);
  	if (rc != 0)
  		goto out;
  
  	dn_neigh_init();
  	dn_dev_init();
  	dn_route_init();
  	dn_fib_init();
  
  	sock_register(&dn_family_ops);
  	dev_add_pack(&dn_dix_packet_type);
  	register_netdevice_notifier(&dn_dev_notifier);

  	proc_net_fops_create(&init_net, "decnet", S_IRUGO, &dn_socket_seq_fops);

  	dn_register_sysctl();
  out:
  	return rc;
  
  }
  module_init(decnet_init);
  
  /*
   * Prevent DECnet module unloading until its fixed properly.
   * Requires an audit of the code to check for memory leaks and
   * initialisation problems etc.
   */
  #if 0
  static void __exit decnet_exit(void)
  {
  	sock_unregister(AF_DECnet);

  	rtnl_unregister_all(PF_DECnet);

  	dev_remove_pack(&dn_dix_packet_type);
  
  	dn_unregister_sysctl();
  
  	unregister_netdevice_notifier(&dn_dev_notifier);
  
  	dn_route_cleanup();
  	dn_dev_cleanup();
  	dn_neigh_cleanup();
  	dn_fib_cleanup();

  	proc_net_remove(&init_net, "decnet");

  
  	proto_unregister(&dn_proto);
  }
  module_exit(decnet_exit);
  #endif