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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/x25/af_x25.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
Diffstat (limited to 'net/x25/af_x25.c')
-rw-r--r--net/x25/af_x25.c1435
1 files changed, 1435 insertions, 0 deletions
diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
new file mode 100644
index 000000000000..2a24b243b841
--- /dev/null
+++ b/net/x25/af_x25.c
@@ -0,0 +1,1435 @@
+/*
+ *	X.25 Packet Layer release 002
+ *
+ *	This is ALPHA test software. This code may break your machine,
+ *	randomly fail to work with new releases, misbehave and/or generally
+ *	screw up. It might even work. 
+ *
+ *	This code REQUIRES 2.1.15 or higher
+ *
+ *	This module:
+ *		This module 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.
+ *
+ *	History
+ *	X.25 001	Jonathan Naylor	Started coding.
+ *	X.25 002	Jonathan Naylor	Centralised disconnect handling.
+ *					New timer architecture.
+ *	2000-03-11	Henner Eisen	MSG_EOR handling more POSIX compliant.
+ *	2000-03-22	Daniela Squassoni Allowed disabling/enabling of 
+ *					  facilities negotiation and increased 
+ *					  the throughput upper limit.
+ *	2000-08-27	Arnaldo C. Melo s/suser/capable/ + micro cleanups
+ *	2000-09-04	Henner Eisen	Set sock->state in x25_accept(). 
+ *					Fixed x25_output() related skb leakage.
+ *	2000-10-02	Henner Eisen	Made x25_kick() single threaded per socket.
+ *	2000-10-27	Henner Eisen    MSG_DONTWAIT for fragment allocation.
+ *	2000-11-14	Henner Eisen    Closing datalink from NETDEV_GOING_DOWN
+ *	2002-10-06	Arnaldo C. Melo Get rid of cli/sti, move proc stuff to
+ *					x25_proc.c, using seq_file
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/tcp.h>
+#include <asm/uaccess.h>
+#include <linux/fcntl.h>
+#include <linux/termios.h>	/* For TIOCINQ/OUTQ */
+#include <linux/notifier.h>
+#include <linux/init.h>
+#include <net/x25.h>
+
+int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
+int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
+int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
+int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
+int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
+
+HLIST_HEAD(x25_list);
+DEFINE_RWLOCK(x25_list_lock);
+
+static struct proto_ops x25_proto_ops;
+
+static struct x25_address null_x25_address = {"               "};
+
+int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
+		  struct x25_address *calling_addr)
+{
+	int called_len, calling_len;
+	char *called, *calling;
+	int i;
+
+	called_len  = (*p >> 0) & 0x0F;
+	calling_len = (*p >> 4) & 0x0F;
+
+	called  = called_addr->x25_addr;
+	calling = calling_addr->x25_addr;
+	p++;
+
+	for (i = 0; i < (called_len + calling_len); i++) {
+		if (i < called_len) {
+			if (i % 2 != 0) {
+				*called++ = ((*p >> 0) & 0x0F) + '0';
+				p++;
+			} else {
+				*called++ = ((*p >> 4) & 0x0F) + '0';
+			}
+		} else {
+			if (i % 2 != 0) {
+				*calling++ = ((*p >> 0) & 0x0F) + '0';
+				p++;
+			} else {
+				*calling++ = ((*p >> 4) & 0x0F) + '0';
+			}
+		}
+	}
+
+	*called = *calling = '\0';
+
+	return 1 + (called_len + calling_len + 1) / 2;
+}
+
+int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
+		  struct x25_address *calling_addr)
+{
+	unsigned int called_len, calling_len;
+	char *called, *calling;
+	int i;
+
+	called  = called_addr->x25_addr;
+	calling = calling_addr->x25_addr;
+
+	called_len  = strlen(called);
+	calling_len = strlen(calling);
+
+	*p++ = (calling_len << 4) | (called_len << 0);
+
+	for (i = 0; i < (called_len + calling_len); i++) {
+		if (i < called_len) {
+			if (i % 2 != 0) {
+				*p |= (*called++ - '0') << 0;
+				p++;
+			} else {
+				*p = 0x00;
+				*p |= (*called++ - '0') << 4;
+			}
+		} else {
+			if (i % 2 != 0) {
+				*p |= (*calling++ - '0') << 0;
+				p++;
+			} else {
+				*p = 0x00;
+				*p |= (*calling++ - '0') << 4;
+			}
+		}
+	}
+
+	return 1 + (called_len + calling_len + 1) / 2;
+}
+
+/*
+ *	Socket removal during an interrupt is now safe.
+ */
+static void x25_remove_socket(struct sock *sk)
+{
+	write_lock_bh(&x25_list_lock);
+	sk_del_node_init(sk);
+	write_unlock_bh(&x25_list_lock);
+}
+
+/*
+ *	Kill all bound sockets on a dropped device.
+ */
+static void x25_kill_by_device(struct net_device *dev)
+{
+	struct sock *s;
+	struct hlist_node *node;
+
+	write_lock_bh(&x25_list_lock);
+
+	sk_for_each(s, node, &x25_list)
+		if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
+			x25_disconnect(s, ENETUNREACH, 0, 0);
+
+	write_unlock_bh(&x25_list_lock);
+}
+
+/*
+ *	Handle device status changes.
+ */
+static int x25_device_event(struct notifier_block *this, unsigned long event,
+			    void *ptr)
+{
+	struct net_device *dev = ptr;
+	struct x25_neigh *nb;
+
+	if (dev->type == ARPHRD_X25
+#if defined(CONFIG_LLC) || defined(CONFIG_LLC_MODULE)
+	 || dev->type == ARPHRD_ETHER
+#endif
+	 ) {
+		switch (event) {
+			case NETDEV_UP:
+				x25_link_device_up(dev);
+				break;
+			case NETDEV_GOING_DOWN:
+				nb = x25_get_neigh(dev);
+				if (nb) {
+					x25_terminate_link(nb);
+					x25_neigh_put(nb);
+				}
+				break;
+			case NETDEV_DOWN:
+				x25_kill_by_device(dev);
+				x25_route_device_down(dev);
+				x25_link_device_down(dev);
+				break;
+		}
+	}
+
+	return NOTIFY_DONE;
+}
+
+/*
+ *	Add a socket to the bound sockets list.
+ */
+static void x25_insert_socket(struct sock *sk)
+{
+	write_lock_bh(&x25_list_lock);
+	sk_add_node(sk, &x25_list);
+	write_unlock_bh(&x25_list_lock);
+}
+
+/*
+ *	Find a socket that wants to accept the Call Request we just
+ *	received. Check the full list for an address/cud match.
+ *	If no cuds match return the next_best thing, an address match.
+ *	Note: if a listening socket has cud set it must only get calls
+ *	with matching cud.
+ */
+static struct sock *x25_find_listener(struct x25_address *addr, struct x25_calluserdata *calluserdata)
+{
+	struct sock *s;
+	struct sock *next_best;
+	struct hlist_node *node;
+
+	read_lock_bh(&x25_list_lock);
+	next_best = NULL;
+
+	sk_for_each(s, node, &x25_list)
+		if ((!strcmp(addr->x25_addr,
+			     x25_sk(s)->source_addr.x25_addr) ||
+		     !strcmp(addr->x25_addr,
+			     null_x25_address.x25_addr)) &&
+		     s->sk_state == TCP_LISTEN) {
+
+			/*
+			 * Found a listening socket, now check the incoming
+			 * call user data vs this sockets call user data
+			 */
+			if (x25_check_calluserdata(&x25_sk(s)->calluserdata, calluserdata)) {
+				sock_hold(s);
+				goto found;
+			}
+			if (x25_sk(s)->calluserdata.cudlength == 0) {
+				next_best = s;
+			}
+		}
+	if (next_best) {
+		s = next_best;
+		sock_hold(s);
+		goto found;
+	}
+	s = NULL;
+found:
+	read_unlock_bh(&x25_list_lock);
+	return s;
+}
+
+/*
+ *	Find a connected X.25 socket given my LCI and neighbour.
+ */
+static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
+{
+	struct sock *s;
+	struct hlist_node *node;
+
+	sk_for_each(s, node, &x25_list)
+		if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
+			sock_hold(s);
+			goto found;
+		}
+	s = NULL;
+found:
+	return s;
+}
+
+struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
+{
+	struct sock *s;
+
+	read_lock_bh(&x25_list_lock);
+	s = __x25_find_socket(lci, nb);
+	read_unlock_bh(&x25_list_lock);
+	return s;
+}
+
+/*
+ *	Find a unique LCI for a given device.
+ */
+static unsigned int x25_new_lci(struct x25_neigh *nb)
+{
+	unsigned int lci = 1;
+	struct sock *sk;
+
+	read_lock_bh(&x25_list_lock);
+
+	while ((sk = __x25_find_socket(lci, nb)) != NULL) {
+		sock_put(sk);
+		if (++lci == 4096) {
+			lci = 0;
+			break;
+		}
+	}
+
+	read_unlock_bh(&x25_list_lock);
+	return lci;
+}
+
+/*
+ *	Deferred destroy.
+ */
+void x25_destroy_socket(struct sock *);
+
+/*
+ *	handler for deferred kills.
+ */
+static void x25_destroy_timer(unsigned long data)
+{
+	x25_destroy_socket((struct sock *)data);
+}
+
+/*
+ *	This is called from user mode and the timers. Thus it protects itself
+ *	against interrupt users but doesn't worry about being called during
+ *	work. Once it is removed from the queue no interrupt or bottom half
+ *	will touch it and we are (fairly 8-) ) safe.
+ *	Not static as it's used by the timer
+ */
+void x25_destroy_socket(struct sock *sk)
+{
+	struct sk_buff *skb;
+
+	sock_hold(sk);
+	lock_sock(sk);
+	x25_stop_heartbeat(sk);
+	x25_stop_timer(sk);
+
+	x25_remove_socket(sk);
+	x25_clear_queues(sk);		/* Flush the queues */
+
+	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
+		if (skb->sk != sk) {		/* A pending connection */
+			/*
+			 * Queue the unaccepted socket for death
+			 */
+			sock_set_flag(skb->sk, SOCK_DEAD);
+			x25_start_heartbeat(skb->sk);
+			x25_sk(skb->sk)->state = X25_STATE_0;
+		}
+
+		kfree_skb(skb);
+	}
+
+	if (atomic_read(&sk->sk_wmem_alloc) ||
+	    atomic_read(&sk->sk_rmem_alloc)) {
+		/* Defer: outstanding buffers */
+		sk->sk_timer.expires  = jiffies + 10 * HZ;
+		sk->sk_timer.function = x25_destroy_timer;
+		sk->sk_timer.data = (unsigned long)sk;
+		add_timer(&sk->sk_timer);
+	} else {
+		/* drop last reference so sock_put will free */
+		__sock_put(sk);
+	}
+
+	release_sock(sk);
+	sock_put(sk);
+}
+
+/*
+ *	Handling for system calls applied via the various interfaces to a
+ *	X.25 socket object.
+ */
+
+static int x25_setsockopt(struct socket *sock, int level, int optname,
+			  char __user *optval, int optlen)
+{
+	int opt;
+	struct sock *sk = sock->sk;
+	int rc = -ENOPROTOOPT;
+
+	if (level != SOL_X25 || optname != X25_QBITINCL)
+		goto out;
+
+	rc = -EINVAL;
+	if (optlen < sizeof(int))
+		goto out;
+
+	rc = -EFAULT;
+	if (get_user(opt, (int __user *)optval))
+		goto out;
+
+	x25_sk(sk)->qbitincl = !!opt;
+	rc = 0;
+out:
+	return rc;
+}
+
+static int x25_getsockopt(struct socket *sock, int level, int optname,
+			  char __user *optval, int __user *optlen)
+{
+	struct sock *sk = sock->sk;
+	int val, len, rc = -ENOPROTOOPT;
+	
+	if (level != SOL_X25 || optname != X25_QBITINCL)
+		goto out;
+
+	rc = -EFAULT;
+	if (get_user(len, optlen))
+		goto out;
+
+	len = min_t(unsigned int, len, sizeof(int));
+
+	rc = -EINVAL;
+	if (len < 0)
+		goto out;
+		
+	rc = -EFAULT;
+	if (put_user(len, optlen))
+		goto out;
+
+	val = x25_sk(sk)->qbitincl;
+	rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
+out:
+	return rc;
+}
+
+static int x25_listen(struct socket *sock, int backlog)
+{
+	struct sock *sk = sock->sk;
+	int rc = -EOPNOTSUPP;
+
+	if (sk->sk_state != TCP_LISTEN) {
+		memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
+		sk->sk_max_ack_backlog = backlog;
+		sk->sk_state           = TCP_LISTEN;
+		rc = 0;
+	}
+
+	return rc;
+}
+
+static struct proto x25_proto = {
+	.name	  = "X25",
+	.owner	  = THIS_MODULE,
+	.obj_size = sizeof(struct x25_sock),
+};
+
+static struct sock *x25_alloc_socket(void)
+{
+	struct x25_sock *x25;
+	struct sock *sk = sk_alloc(AF_X25, GFP_ATOMIC, &x25_proto, 1);
+
+	if (!sk)
+		goto out;
+
+	sock_init_data(NULL, sk);
+
+	x25 = x25_sk(sk);
+	skb_queue_head_init(&x25->ack_queue);
+	skb_queue_head_init(&x25->fragment_queue);
+	skb_queue_head_init(&x25->interrupt_in_queue);
+	skb_queue_head_init(&x25->interrupt_out_queue);
+out:
+	return sk;
+}
+
+void x25_init_timers(struct sock *sk);
+
+static int x25_create(struct socket *sock, int protocol)
+{
+	struct sock *sk;
+	struct x25_sock *x25;
+	int rc = -ESOCKTNOSUPPORT;
+
+	if (sock->type != SOCK_SEQPACKET || protocol)
+		goto out;
+
+	rc = -ENOMEM;
+	if ((sk = x25_alloc_socket()) == NULL)
+		goto out;
+
+	x25 = x25_sk(sk);
+
+	sock_init_data(sock, sk);
+
+	x25_init_timers(sk);
+
+	sock->ops    = &x25_proto_ops;
+	sk->sk_protocol = protocol;
+	sk->sk_backlog_rcv = x25_backlog_rcv;
+
+	x25->t21   = sysctl_x25_call_request_timeout;
+	x25->t22   = sysctl_x25_reset_request_timeout;
+	x25->t23   = sysctl_x25_clear_request_timeout;
+	x25->t2    = sysctl_x25_ack_holdback_timeout;
+	x25->state = X25_STATE_0;
+
+	x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
+	x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
+	x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
+	x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
+	x25->facilities.throughput  = X25_DEFAULT_THROUGHPUT;
+	x25->facilities.reverse     = X25_DEFAULT_REVERSE;
+	rc = 0;
+out:
+	return rc;
+}
+
+static struct sock *x25_make_new(struct sock *osk)
+{
+	struct sock *sk = NULL;
+	struct x25_sock *x25, *ox25;
+
+	if (osk->sk_type != SOCK_SEQPACKET)
+		goto out;
+
+	if ((sk = x25_alloc_socket()) == NULL)
+		goto out;
+
+	x25 = x25_sk(sk);
+
+	sk->sk_type        = osk->sk_type;
+	sk->sk_socket      = osk->sk_socket;
+	sk->sk_priority    = osk->sk_priority;
+	sk->sk_protocol    = osk->sk_protocol;
+	sk->sk_rcvbuf      = osk->sk_rcvbuf;
+	sk->sk_sndbuf      = osk->sk_sndbuf;
+	sk->sk_state       = TCP_ESTABLISHED;
+	sk->sk_sleep       = osk->sk_sleep;
+	sk->sk_backlog_rcv = osk->sk_backlog_rcv;
+
+	if (sock_flag(osk, SOCK_ZAPPED))
+		sock_set_flag(sk, SOCK_ZAPPED);
+	
+	if (sock_flag(osk, SOCK_DBG))
+		sock_set_flag(sk, SOCK_DBG);
+
+	ox25 = x25_sk(osk);
+	x25->t21        = ox25->t21;
+	x25->t22        = ox25->t22;
+	x25->t23        = ox25->t23;
+	x25->t2         = ox25->t2;
+	x25->facilities = ox25->facilities;
+	x25->qbitincl   = ox25->qbitincl;
+
+	x25_init_timers(sk);
+out:
+	return sk;
+}
+
+static int x25_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct x25_sock *x25;
+
+	if (!sk)
+		goto out;
+
+	x25 = x25_sk(sk);
+
+	switch (x25->state) {
+
+		case X25_STATE_0:
+		case X25_STATE_2:
+			x25_disconnect(sk, 0, 0, 0);
+			x25_destroy_socket(sk);
+			goto out;
+
+		case X25_STATE_1:
+		case X25_STATE_3:
+		case X25_STATE_4:
+			x25_clear_queues(sk);
+			x25_write_internal(sk, X25_CLEAR_REQUEST);
+			x25_start_t23timer(sk);
+			x25->state = X25_STATE_2;
+			sk->sk_state	= TCP_CLOSE;
+			sk->sk_shutdown	|= SEND_SHUTDOWN;
+			sk->sk_state_change(sk);
+			sock_set_flag(sk, SOCK_DEAD);
+			sock_set_flag(sk, SOCK_DESTROY);
+			break;
+	}
+
+	sock->sk	= NULL;	
+	sk->sk_socket	= NULL;	/* Not used, but we should do this */
+out:
+	return 0;
+}
+
+static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
+{
+	struct sock *sk = sock->sk;
+	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
+
+	if (!sock_flag(sk, SOCK_ZAPPED) ||
+	    addr_len != sizeof(struct sockaddr_x25) ||
+	    addr->sx25_family != AF_X25)
+		return -EINVAL;
+
+	x25_sk(sk)->source_addr = addr->sx25_addr;
+	x25_insert_socket(sk);
+	sock_reset_flag(sk, SOCK_ZAPPED);
+	SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
+
+	return 0;
+}
+
+static int x25_wait_for_connection_establishment(struct sock *sk)
+{
+	DECLARE_WAITQUEUE(wait, current);
+        int rc;
+
+	add_wait_queue_exclusive(sk->sk_sleep, &wait);
+	for (;;) {
+		__set_current_state(TASK_INTERRUPTIBLE);
+		rc = -ERESTARTSYS;
+		if (signal_pending(current))
+			break;
+		rc = sock_error(sk);
+		if (rc) {
+			sk->sk_socket->state = SS_UNCONNECTED;
+			break;
+		}
+		rc = 0;
+		if (sk->sk_state != TCP_ESTABLISHED) {
+			release_sock(sk);
+			schedule();
+			lock_sock(sk);
+		} else
+			break;
+	}
+	__set_current_state(TASK_RUNNING);
+	remove_wait_queue(sk->sk_sleep, &wait);
+	return rc;
+}
+
+static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
+		       int addr_len, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct x25_sock *x25 = x25_sk(sk);
+	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
+	struct x25_route *rt;
+	int rc = 0;
+
+	lock_sock(sk);
+	if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
+		sock->state = SS_CONNECTED;
+		goto out; /* Connect completed during a ERESTARTSYS event */
+	}
+
+	rc = -ECONNREFUSED;
+	if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
+		sock->state = SS_UNCONNECTED;
+		goto out;
+	}
+
+	rc = -EISCONN;	/* No reconnect on a seqpacket socket */
+	if (sk->sk_state == TCP_ESTABLISHED)
+		goto out;
+
+	sk->sk_state   = TCP_CLOSE;	
+	sock->state = SS_UNCONNECTED;
+
+	rc = -EINVAL;
+	if (addr_len != sizeof(struct sockaddr_x25) ||
+	    addr->sx25_family != AF_X25)
+		goto out;
+
+	rc = -ENETUNREACH;
+	rt = x25_get_route(&addr->sx25_addr);
+	if (!rt)
+		goto out;
+
+	x25->neighbour = x25_get_neigh(rt->dev);
+	if (!x25->neighbour)
+		goto out_put_route;
+
+	x25_limit_facilities(&x25->facilities, x25->neighbour);
+
+	x25->lci = x25_new_lci(x25->neighbour);
+	if (!x25->lci)
+		goto out_put_neigh;
+
+	rc = -EINVAL;
+	if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
+		goto out_put_neigh;
+
+	if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
+		memset(&x25->source_addr, '\0', X25_ADDR_LEN);
+
+	x25->dest_addr = addr->sx25_addr;
+
+	/* Move to connecting socket, start sending Connect Requests */
+	sock->state   = SS_CONNECTING;
+	sk->sk_state  = TCP_SYN_SENT;
+
+	x25->state = X25_STATE_1;
+
+	x25_write_internal(sk, X25_CALL_REQUEST);
+
+	x25_start_heartbeat(sk);
+	x25_start_t21timer(sk);
+
+	/* Now the loop */
+	rc = -EINPROGRESS;
+	if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
+		goto out_put_neigh;
+
+	rc = x25_wait_for_connection_establishment(sk);
+	if (rc)
+		goto out_put_neigh;
+
+	sock->state = SS_CONNECTED;
+	rc = 0;
+out_put_neigh:
+	if (rc)
+		x25_neigh_put(x25->neighbour);
+out_put_route:
+	x25_route_put(rt);
+out:
+	release_sock(sk);
+	return rc;
+}
+
+static int x25_wait_for_data(struct sock *sk, int timeout)
+{
+	DECLARE_WAITQUEUE(wait, current);
+	int rc = 0;
+
+	add_wait_queue_exclusive(sk->sk_sleep, &wait);
+	for (;;) {
+		__set_current_state(TASK_INTERRUPTIBLE);
+		if (sk->sk_shutdown & RCV_SHUTDOWN)
+			break;
+		rc = -ERESTARTSYS;
+		if (signal_pending(current))
+			break;
+		rc = -EAGAIN;
+		if (!timeout)
+			break;
+		rc = 0;
+		if (skb_queue_empty(&sk->sk_receive_queue)) {
+			release_sock(sk);
+			timeout = schedule_timeout(timeout);
+			lock_sock(sk);
+		} else
+			break;
+	}
+	__set_current_state(TASK_RUNNING);
+	remove_wait_queue(sk->sk_sleep, &wait);
+	return rc;
+}
+	
+static int x25_accept(struct socket *sock, struct socket *newsock, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct sock *newsk;
+	struct sk_buff *skb;
+	int rc = -EINVAL;
+
+	if (!sk || sk->sk_state != TCP_LISTEN)
+		goto out;
+
+	rc = -EOPNOTSUPP;
+	if (sk->sk_type != SOCK_SEQPACKET)
+		goto out;
+
+	lock_sock(sk);
+	rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
+	if (rc)
+		goto out2;
+	skb = skb_dequeue(&sk->sk_receive_queue);
+	rc = -EINVAL;
+	if (!skb->sk)
+		goto out2;
+	newsk		 = skb->sk;
+	newsk->sk_socket = newsock;
+	newsk->sk_sleep  = &newsock->wait;
+
+	/* Now attach up the new socket */
+	skb->sk = NULL;
+	kfree_skb(skb);
+	sk->sk_ack_backlog--;
+	newsock->sk    = newsk;
+	newsock->state = SS_CONNECTED;
+	rc = 0;
+out2:
+	release_sock(sk);
+out:
+	return rc;
+}
+
+static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
+		       int *uaddr_len, int peer)
+{
+	struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
+	struct sock *sk = sock->sk;
+	struct x25_sock *x25 = x25_sk(sk);
+
+	if (peer) {
+		if (sk->sk_state != TCP_ESTABLISHED)
+			return -ENOTCONN;
+		sx25->sx25_addr = x25->dest_addr;
+	} else
+		sx25->sx25_addr = x25->source_addr;
+
+	sx25->sx25_family = AF_X25;
+	*uaddr_len = sizeof(*sx25);
+
+	return 0;
+}
+ 
+int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
+			unsigned int lci)
+{
+	struct sock *sk;
+	struct sock *make;
+	struct x25_sock *makex25;
+	struct x25_address source_addr, dest_addr;
+	struct x25_facilities facilities;
+	struct x25_calluserdata calluserdata;
+	int len, rc;
+
+	/*
+	 *	Remove the LCI and frame type.
+	 */
+	skb_pull(skb, X25_STD_MIN_LEN);
+
+	/*
+	 *	Extract the X.25 addresses and convert them to ASCII strings,
+	 *	and remove them.
+	 */
+	skb_pull(skb, x25_addr_ntoa(skb->data, &source_addr, &dest_addr));
+
+	/*
+	 *	Get the length of the facilities, skip past them for the moment
+	 *	get the call user data because this is needed to determine
+	 *	the correct listener
+	 */
+	len = skb->data[0] + 1;
+	skb_pull(skb,len);
+
+	/*
+	 *	Incoming Call User Data.
+	 */
+	if (skb->len >= 0) {
+		memcpy(calluserdata.cuddata, skb->data, skb->len);
+		calluserdata.cudlength = skb->len;
+	}
+
+	skb_push(skb,len);
+
+	/*
+	 *	Find a listener for the particular address/cud pair.
+	 */
+	sk = x25_find_listener(&source_addr,&calluserdata);
+
+	/*
+	 *	We can't accept the Call Request.
+	 */
+	if (sk == NULL || sk_acceptq_is_full(sk))
+		goto out_clear_request;
+
+	/*
+	 *	Try to reach a compromise on the requested facilities.
+	 */
+	if ((len = x25_negotiate_facilities(skb, sk, &facilities)) == -1)
+		goto out_sock_put;
+
+	/*
+	 * current neighbour/link might impose additional limits
+	 * on certain facilties
+	 */
+
+	x25_limit_facilities(&facilities, nb);
+
+	/*
+	 *	Try to create a new socket.
+	 */
+	make = x25_make_new(sk);
+	if (!make)
+		goto out_sock_put;
+
+	/*
+	 *	Remove the facilities
+	 */
+	skb_pull(skb, len);
+
+	skb->sk     = make;
+	make->sk_state = TCP_ESTABLISHED;
+
+	makex25 = x25_sk(make);
+	makex25->lci           = lci;
+	makex25->dest_addr     = dest_addr;
+	makex25->source_addr   = source_addr;
+	makex25->neighbour     = nb;
+	makex25->facilities    = facilities;
+	makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
+	makex25->calluserdata  = calluserdata;
+
+	x25_write_internal(make, X25_CALL_ACCEPTED);
+
+	makex25->state = X25_STATE_3;
+
+	sk->sk_ack_backlog++;
+
+	x25_insert_socket(make);
+
+	skb_queue_head(&sk->sk_receive_queue, skb);
+
+	x25_start_heartbeat(make);
+
+	if (!sock_flag(sk, SOCK_DEAD))
+		sk->sk_data_ready(sk, skb->len);
+	rc = 1;
+	sock_put(sk);
+out:
+	return rc;
+out_sock_put:
+	sock_put(sk);
+out_clear_request:
+	rc = 0;
+	x25_transmit_clear_request(nb, lci, 0x01);
+	goto out;
+}
+
+static int x25_sendmsg(struct kiocb *iocb, struct socket *sock,
+		       struct msghdr *msg, size_t len)
+{
+	struct sock *sk = sock->sk;
+	struct x25_sock *x25 = x25_sk(sk);
+	struct sockaddr_x25 *usx25 = (struct sockaddr_x25 *)msg->msg_name;
+	struct sockaddr_x25 sx25;
+	struct sk_buff *skb;
+	unsigned char *asmptr;
+	int noblock = msg->msg_flags & MSG_DONTWAIT;
+	size_t size;
+	int qbit = 0, rc = -EINVAL;
+
+	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
+		goto out;
+
+	/* we currently don't support segmented records at the user interface */
+	if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
+		goto out;
+
+	rc = -EADDRNOTAVAIL;
+	if (sock_flag(sk, SOCK_ZAPPED))
+		goto out;
+
+	rc = -EPIPE;
+	if (sk->sk_shutdown & SEND_SHUTDOWN) {
+		send_sig(SIGPIPE, current, 0);
+		goto out;
+	}
+
+	rc = -ENETUNREACH;
+	if (!x25->neighbour)
+		goto out;
+
+	if (usx25) {
+		rc = -EINVAL;
+		if (msg->msg_namelen < sizeof(sx25))
+			goto out;
+		memcpy(&sx25, usx25, sizeof(sx25));
+		rc = -EISCONN;
+		if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
+			goto out;
+		rc = -EINVAL;
+		if (sx25.sx25_family != AF_X25)
+			goto out;
+	} else {
+		/*
+		 *	FIXME 1003.1g - if the socket is like this because
+		 *	it has become closed (not started closed) we ought
+		 *	to SIGPIPE, EPIPE;
+		 */
+		rc = -ENOTCONN;
+		if (sk->sk_state != TCP_ESTABLISHED)
+			goto out;
+
+		sx25.sx25_family = AF_X25;
+		sx25.sx25_addr   = x25->dest_addr;
+	}
+
+	SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
+
+	/* Build a packet */
+	SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
+
+	if ((msg->msg_flags & MSG_OOB) && len > 32)
+		len = 32;
+
+	size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
+
+	skb = sock_alloc_send_skb(sk, size, noblock, &rc);
+	if (!skb)
+		goto out;
+	X25_SKB_CB(skb)->flags = msg->msg_flags;
+
+	skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
+
+	/*
+	 *	Put the data on the end
+	 */
+	SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
+
+	asmptr = skb->h.raw = skb_put(skb, len);
+
+	rc = memcpy_fromiovec(asmptr, msg->msg_iov, len);
+	if (rc)
+		goto out_kfree_skb;
+
+	/*
+	 *	If the Q BIT Include socket option is in force, the first
+	 *	byte of the user data is the logical value of the Q Bit.
+	 */
+	if (x25->qbitincl) {
+		qbit = skb->data[0];
+		skb_pull(skb, 1);
+	}
+
+	/*
+	 *	Push down the X.25 header
+	 */
+	SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
+
+	if (msg->msg_flags & MSG_OOB) {
+		if (x25->neighbour->extended) {
+			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
+			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
+			*asmptr++ = (x25->lci >> 0) & 0xFF;
+			*asmptr++ = X25_INTERRUPT;
+		} else {
+			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
+			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
+			*asmptr++ = (x25->lci >> 0) & 0xFF;
+			*asmptr++ = X25_INTERRUPT;
+		}
+	} else {
+		if (x25->neighbour->extended) {
+			/* Build an Extended X.25 header */
+			asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
+			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
+			*asmptr++ = (x25->lci >> 0) & 0xFF;
+			*asmptr++ = X25_DATA;
+			*asmptr++ = X25_DATA;
+		} else {
+			/* Build an Standard X.25 header */
+			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
+			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
+			*asmptr++ = (x25->lci >> 0) & 0xFF;
+			*asmptr++ = X25_DATA;
+		}
+
+		if (qbit)
+			skb->data[0] |= X25_Q_BIT;
+	}
+
+	SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
+	SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
+
+	rc = -ENOTCONN;
+	if (sk->sk_state != TCP_ESTABLISHED)
+		goto out_kfree_skb;
+
+	if (msg->msg_flags & MSG_OOB)
+		skb_queue_tail(&x25->interrupt_out_queue, skb);
+	else {
+	        len = x25_output(sk, skb);
+		if (len < 0)
+			kfree_skb(skb);
+		else if (x25->qbitincl)
+			len++;
+	}
+
+	/*
+	 * lock_sock() is currently only used to serialize this x25_kick()
+	 * against input-driven x25_kick() calls. It currently only blocks
+	 * incoming packets for this socket and does not protect against
+	 * any other socket state changes and is not called from anywhere
+	 * else. As x25_kick() cannot block and as long as all socket
+	 * operations are BKL-wrapped, we don't need take to care about
+	 * purging the backlog queue in x25_release().
+	 *
+	 * Using lock_sock() to protect all socket operations entirely
+	 * (and making the whole x25 stack SMP aware) unfortunately would
+	 * require major changes to {send,recv}msg and skb allocation methods.
+	 * -> 2.5 ;)
+	 */
+	lock_sock(sk);
+	x25_kick(sk);
+	release_sock(sk);
+	rc = len;
+out:
+	return rc;
+out_kfree_skb:
+	kfree_skb(skb);
+	goto out;
+}
+
+
+static int x25_recvmsg(struct kiocb *iocb, struct socket *sock,
+		       struct msghdr *msg, size_t size,
+		       int flags)
+{
+	struct sock *sk = sock->sk;
+	struct x25_sock *x25 = x25_sk(sk);
+	struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)msg->msg_name;
+	size_t copied;
+	int qbit;
+	struct sk_buff *skb;
+	unsigned char *asmptr;
+	int rc = -ENOTCONN;
+
+	/*
+	 * This works for seqpacket too. The receiver has ordered the queue for
+	 * us! We do one quick check first though
+	 */
+	if (sk->sk_state != TCP_ESTABLISHED)
+		goto out;
+
+	if (flags & MSG_OOB) {
+		rc = -EINVAL;
+		if (sock_flag(sk, SOCK_URGINLINE) ||
+		    !skb_peek(&x25->interrupt_in_queue))
+			goto out;
+
+		skb = skb_dequeue(&x25->interrupt_in_queue);
+
+		skb_pull(skb, X25_STD_MIN_LEN);
+
+		/*
+		 *	No Q bit information on Interrupt data.
+		 */
+		if (x25->qbitincl) {
+			asmptr  = skb_push(skb, 1);
+			*asmptr = 0x00;
+		}
+
+		msg->msg_flags |= MSG_OOB;
+	} else {
+		/* Now we can treat all alike */
+		skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
+					flags & MSG_DONTWAIT, &rc);
+		if (!skb)
+			goto out;
+
+		qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
+
+		skb_pull(skb, x25->neighbour->extended ?
+				X25_EXT_MIN_LEN : X25_STD_MIN_LEN);
+
+		if (x25->qbitincl) {
+			asmptr  = skb_push(skb, 1);
+			*asmptr = qbit;
+		}
+	}
+
+	skb->h.raw = skb->data;
+
+	copied = skb->len;
+
+	if (copied > size) {
+		copied = size;
+		msg->msg_flags |= MSG_TRUNC;
+	}
+
+	/* Currently, each datagram always contains a complete record */ 
+	msg->msg_flags |= MSG_EOR;
+
+	rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
+	if (rc)
+		goto out_free_dgram;
+
+	if (sx25) {
+		sx25->sx25_family = AF_X25;
+		sx25->sx25_addr   = x25->dest_addr;
+	}
+
+	msg->msg_namelen = sizeof(struct sockaddr_x25);
+
+	lock_sock(sk);
+	x25_check_rbuf(sk);
+	release_sock(sk);
+	rc = copied;
+out_free_dgram:
+	skb_free_datagram(sk, skb);
+out:
+	return rc;
+}
+
+
+static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	struct sock *sk = sock->sk;
+	struct x25_sock *x25 = x25_sk(sk);
+	void __user *argp = (void __user *)arg;
+	int rc;
+
+	switch (cmd) {
+		case TIOCOUTQ: {
+			int amount = sk->sk_sndbuf -
+				     atomic_read(&sk->sk_wmem_alloc);
+			if (amount < 0)
+				amount = 0;
+			rc = put_user(amount, (unsigned int __user *)argp);
+			break;
+		}
+
+		case TIOCINQ: {
+			struct sk_buff *skb;
+			int amount = 0;
+			/*
+			 * These two are safe on a single CPU system as
+			 * only user tasks fiddle here
+			 */
+			if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
+				amount = skb->len;
+			rc = put_user(amount, (unsigned int __user *)argp);
+			break;
+		}
+
+		case SIOCGSTAMP:
+			rc = -EINVAL;
+			if (sk)
+				rc = sock_get_timestamp(sk, 
+						(struct timeval __user *)argp); 
+			break;
+		case SIOCGIFADDR:
+		case SIOCSIFADDR:
+		case SIOCGIFDSTADDR:
+		case SIOCSIFDSTADDR:
+		case SIOCGIFBRDADDR:
+		case SIOCSIFBRDADDR:
+		case SIOCGIFNETMASK:
+		case SIOCSIFNETMASK:
+		case SIOCGIFMETRIC:
+		case SIOCSIFMETRIC:
+			rc = -EINVAL;
+			break;
+		case SIOCADDRT:
+		case SIOCDELRT:
+			rc = -EPERM;
+			if (!capable(CAP_NET_ADMIN))
+				break;
+			rc = x25_route_ioctl(cmd, argp);
+			break;
+		case SIOCX25GSUBSCRIP:
+			rc = x25_subscr_ioctl(cmd, argp);
+			break;
+		case SIOCX25SSUBSCRIP:
+			rc = -EPERM;
+			if (!capable(CAP_NET_ADMIN))
+				break;
+			rc = x25_subscr_ioctl(cmd, argp);
+			break;
+		case SIOCX25GFACILITIES: {
+			struct x25_facilities fac = x25->facilities;
+			rc = copy_to_user(argp, &fac,
+					  sizeof(fac)) ? -EFAULT : 0;
+			break;
+		}
+
+		case SIOCX25SFACILITIES: {
+			struct x25_facilities facilities;
+			rc = -EFAULT;
+			if (copy_from_user(&facilities, argp,
+					   sizeof(facilities)))
+				break;
+			rc = -EINVAL;
+			if (sk->sk_state != TCP_LISTEN &&
+			    sk->sk_state != TCP_CLOSE)
+				break;
+			if (facilities.pacsize_in < X25_PS16 ||
+			    facilities.pacsize_in > X25_PS4096)
+				break;
+			if (facilities.pacsize_out < X25_PS16 ||
+			    facilities.pacsize_out > X25_PS4096)
+				break;
+			if (facilities.winsize_in < 1 ||
+			    facilities.winsize_in > 127)
+				break;
+			if (facilities.throughput < 0x03 ||
+			    facilities.throughput > 0xDD)
+				break;
+			if (facilities.reverse && facilities.reverse != 1)
+				break;
+			x25->facilities = facilities;
+			rc = 0;
+			break;
+		}
+
+		case SIOCX25GCALLUSERDATA: {
+			struct x25_calluserdata cud = x25->calluserdata;
+			rc = copy_to_user(argp, &cud,
+					  sizeof(cud)) ? -EFAULT : 0;
+			break;
+		}
+
+		case SIOCX25SCALLUSERDATA: {
+			struct x25_calluserdata calluserdata;
+
+			rc = -EFAULT;
+			if (copy_from_user(&calluserdata, argp,
+					   sizeof(calluserdata)))
+				break;
+			rc = -EINVAL;
+			if (calluserdata.cudlength > X25_MAX_CUD_LEN)
+				break;
+			x25->calluserdata = calluserdata;
+			rc = 0;
+			break;
+		}
+
+		case SIOCX25GCAUSEDIAG: {
+			struct x25_causediag causediag;
+			causediag = x25->causediag;
+			rc = copy_to_user(argp, &causediag,
+					  sizeof(causediag)) ? -EFAULT : 0;
+			break;
+		}
+
+ 		default:
+			rc = dev_ioctl(cmd, argp);
+			break;
+	}
+
+	return rc;
+}
+
+static struct net_proto_family x25_family_ops = {
+	.family =	AF_X25,
+	.create =	x25_create,
+	.owner	=	THIS_MODULE,
+};
+
+static struct proto_ops SOCKOPS_WRAPPED(x25_proto_ops) = {
+	.family =	AF_X25,
+	.owner =	THIS_MODULE,
+	.release =	x25_release,
+	.bind =		x25_bind,
+	.connect =	x25_connect,
+	.socketpair =	sock_no_socketpair,
+	.accept =	x25_accept,
+	.getname =	x25_getname,
+	.poll =		datagram_poll,
+	.ioctl =	x25_ioctl,
+	.listen =	x25_listen,
+	.shutdown =	sock_no_shutdown,
+	.setsockopt =	x25_setsockopt,
+	.getsockopt =	x25_getsockopt,
+	.sendmsg =	x25_sendmsg,
+	.recvmsg =	x25_recvmsg,
+	.mmap =		sock_no_mmap,
+	.sendpage =	sock_no_sendpage,
+};
+
+#include <linux/smp_lock.h>
+SOCKOPS_WRAP(x25_proto, AF_X25);
+
+static struct packet_type x25_packet_type = {
+	.type =	__constant_htons(ETH_P_X25),
+	.func =	x25_lapb_receive_frame,
+};
+
+static struct notifier_block x25_dev_notifier = {
+	.notifier_call = x25_device_event,
+};
+
+void x25_kill_by_neigh(struct x25_neigh *nb)
+{
+	struct sock *s;
+	struct hlist_node *node;
+
+	write_lock_bh(&x25_list_lock);
+
+	sk_for_each(s, node, &x25_list)
+		if (x25_sk(s)->neighbour == nb)
+			x25_disconnect(s, ENETUNREACH, 0, 0);
+
+	write_unlock_bh(&x25_list_lock);
+}
+
+static int __init x25_init(void)
+{
+	int rc = proto_register(&x25_proto, 0);
+
+	if (rc != 0)
+		goto out;
+
+	sock_register(&x25_family_ops);
+
+	dev_add_pack(&x25_packet_type);
+
+	register_netdevice_notifier(&x25_dev_notifier);
+
+	printk(KERN_INFO "X.25 for Linux. Version 0.2 for Linux 2.1.15\n");
+
+#ifdef CONFIG_SYSCTL
+	x25_register_sysctl();
+#endif
+	x25_proc_init();
+out:
+	return rc;
+}
+module_init(x25_init);
+
+static void __exit x25_exit(void)
+{
+	x25_proc_exit();
+	x25_link_free();
+	x25_route_free();
+
+#ifdef CONFIG_SYSCTL
+	x25_unregister_sysctl();
+#endif
+
+	unregister_netdevice_notifier(&x25_dev_notifier);
+
+	dev_remove_pack(&x25_packet_type);
+
+	sock_unregister(AF_X25);
+	proto_unregister(&x25_proto);
+}
+module_exit(x25_exit);
+
+MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
+MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(PF_X25);