Initial import

1 files changed, 1188 insertions, 0 deletions

diff --git a/net/irda/irnet/irnet_ppp.c b/net/irda/irnet/irnet_ppp.c
new file mode 100644
index 000000000..1215693fd
--- /dev/null
+++ b/net/irda/irnet/irnet_ppp.c
@@ -0,0 +1,1188 @@
+/*
+ *	IrNET protocol module : Synchronous PPP over an IrDA socket.
+ *
+ *		Jean II - HPL `00 - <jt@hpl.hp.com>
+ *
+ * This file implement the PPP interface and /dev/irnet character device.
+ * The PPP interface hook to the ppp_generic module, handle all our
+ *	relationship to the PPP code in the kernel (and by extension to pppd),
+ *	and exchange PPP frames with this module (send/receive).
+ * The /dev/irnet device is used primarily for 2 functions :
+ *	1) as a stub for pppd (the ppp daemon), so that we can appropriately
+ *	generate PPP sessions (we pretend we are a tty).
+ *	2) as a control channel (write commands, read events)
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include "irnet_ppp.h"		/* Private header */
+/* Please put other headers in irnet.h - Thanks */
+
+/* Generic PPP callbacks (to call us) */
+static const struct ppp_channel_ops irnet_ppp_ops = {
+	.start_xmit = ppp_irnet_send,
+	.ioctl = ppp_irnet_ioctl
+};
+
+/************************* CONTROL CHANNEL *************************/
+/*
+ * When a pppd instance is not active on /dev/irnet, it acts as a control
+ * channel.
+ * Writing allow to set up the IrDA destination of the IrNET channel,
+ * and any application may be read events happening in IrNET...
+ */
+
+/*------------------------------------------------------------------*/
+/*
+ * Write is used to send a command to configure a IrNET channel
+ * before it is open by pppd. The syntax is : "command argument"
+ * Currently there is only two defined commands :
+ *	o name : set the requested IrDA nickname of the IrNET peer.
+ *	o addr : set the requested IrDA address of the IrNET peer.
+ * Note : the code is crude, but effective...
+ */
+static inline ssize_t
+irnet_ctrl_write(irnet_socket *	ap,
+		 const char __user *buf,
+		 size_t		count)
+{
+  char		command[IRNET_MAX_COMMAND];
+  char *	start;		/* Current command being processed */
+  char *	next;		/* Next command to process */
+  int		length;		/* Length of current command */
+
+  DENTER(CTRL_TRACE, "(ap=0x%p, count=%Zd)\n", ap, count);
+
+  /* Check for overflow... */
+  DABORT(count >= IRNET_MAX_COMMAND, -ENOMEM,
+	 CTRL_ERROR, "Too much data !!!\n");
+
+  /* Get the data in the driver */
+  if(copy_from_user(command, buf, count))
+    {
+      DERROR(CTRL_ERROR, "Invalid user space pointer.\n");
+      return -EFAULT;
+    }
+
+  /* Safe terminate the string */
+  command[count] = '\0';
+  DEBUG(CTRL_INFO, "Command line received is ``%s'' (%Zd).\n",
+	command, count);
+
+  /* Check every commands in the command line */
+  next = command;
+  while(next != NULL)
+    {
+      /* Look at the next command */
+      start = next;
+
+	/* Scrap whitespaces before the command */
+	start = skip_spaces(start);
+
+      /* ',' is our command separator */
+      next = strchr(start, ',');
+      if(next)
+	{
+	  *next = '\0';			/* Terminate command */
+	  length = next - start;	/* Length */
+	  next++;			/* Skip the '\0' */
+	}
+      else
+	length = strlen(start);
+
+      DEBUG(CTRL_INFO, "Found command ``%s'' (%d).\n", start, length);
+
+      /* Check if we recognised one of the known command
+       * We can't use "switch" with strings, so hack with "continue" */
+
+      /* First command : name -> Requested IrDA nickname */
+      if(!strncmp(start, "name", 4))
+	{
+	  /* Copy the name only if is included and not "any" */
+	  if((length > 5) && (strcmp(start + 5, "any")))
+	    {
+	      /* Strip out trailing whitespaces */
+	      while(isspace(start[length - 1]))
+		length--;
+
+	      DABORT(length < 5 || length > NICKNAME_MAX_LEN + 5,
+		     -EINVAL, CTRL_ERROR, "Invalid nickname.\n");
+
+	      /* Copy the name for later reuse */
+	      memcpy(ap->rname, start + 5, length - 5);
+	      ap->rname[length - 5] = '\0';
+	    }
+	  else
+	    ap->rname[0] = '\0';
+	  DEBUG(CTRL_INFO, "Got rname = ``%s''\n", ap->rname);
+
+	  /* Restart the loop */
+	  continue;
+	}
+
+      /* Second command : addr, daddr -> Requested IrDA destination address
+       * Also process : saddr -> Requested IrDA source address */
+      if((!strncmp(start, "addr", 4)) ||
+	 (!strncmp(start, "daddr", 5)) ||
+	 (!strncmp(start, "saddr", 5)))
+	{
+	  __u32		addr = DEV_ADDR_ANY;
+
+	  /* Copy the address only if is included and not "any" */
+	  if((length > 5) && (strcmp(start + 5, "any")))
+	    {
+	      char *	begp = start + 5;
+	      char *	endp;
+
+	      /* Scrap whitespaces before the command */
+	      begp = skip_spaces(begp);
+
+	      /* Convert argument to a number (last arg is the base) */
+	      addr = simple_strtoul(begp, &endp, 16);
+	      /* Has it worked  ? (endp should be start + length) */
+	      DABORT(endp <= (start + 5), -EINVAL,
+		     CTRL_ERROR, "Invalid address.\n");
+	    }
+	  /* Which type of address ? */
+	  if(start[0] == 's')
+	    {
+	      /* Save it */
+	      ap->rsaddr = addr;
+	      DEBUG(CTRL_INFO, "Got rsaddr = %08x\n", ap->rsaddr);
+	    }
+	  else
+	    {
+	      /* Save it */
+	      ap->rdaddr = addr;
+	      DEBUG(CTRL_INFO, "Got rdaddr = %08x\n", ap->rdaddr);
+	    }
+
+	  /* Restart the loop */
+	  continue;
+	}
+
+      /* Other possible command : connect N (number of retries) */
+
+      /* No command matched -> Failed... */
+      DABORT(1, -EINVAL, CTRL_ERROR, "Not a recognised IrNET command.\n");
+    }
+
+  /* Success : we have parsed all commands successfully */
+  return count;
+}
+
+#ifdef INITIAL_DISCOVERY
+/*------------------------------------------------------------------*/
+/*
+ * Function irnet_get_discovery_log (self)
+ *
+ *    Query the content on the discovery log if not done
+ *
+ * This function query the current content of the discovery log
+ * at the startup of the event channel and save it in the internal struct.
+ */
+static void
+irnet_get_discovery_log(irnet_socket *	ap)
+{
+  __u16		mask = irlmp_service_to_hint(S_LAN);
+
+  /* Ask IrLMP for the current discovery log */
+  ap->discoveries = irlmp_get_discoveries(&ap->disco_number, mask,
+					  DISCOVERY_DEFAULT_SLOTS);
+
+  /* Check if the we got some results */
+  if(ap->discoveries == NULL)
+    ap->disco_number = -1;
+
+  DEBUG(CTRL_INFO, "Got the log (0x%p), size is %d\n",
+	ap->discoveries, ap->disco_number);
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Function irnet_read_discovery_log (self, event)
+ *
+ *    Read the content on the discovery log
+ *
+ * This function dump the current content of the discovery log
+ * at the startup of the event channel.
+ * Return 1 if wrote an event on the control channel...
+ *
+ * State of the ap->disco_XXX variables :
+ * Socket creation :  discoveries = NULL ; disco_index = 0 ; disco_number = 0
+ * While reading :    discoveries = ptr  ; disco_index = X ; disco_number = Y
+ * After reading :    discoveries = NULL ; disco_index = Y ; disco_number = -1
+ */
+static inline int
+irnet_read_discovery_log(irnet_socket *ap, char *event, int buf_size)
+{
+  int		done_event = 0;
+
+  DENTER(CTRL_TRACE, "(ap=0x%p, event=0x%p)\n",
+	 ap, event);
+
+  /* Test if we have some work to do or we have already finished */
+  if(ap->disco_number == -1)
+    {
+      DEBUG(CTRL_INFO, "Already done\n");
+      return 0;
+    }
+
+  /* Test if it's the first time and therefore we need to get the log */
+  if(ap->discoveries == NULL)
+    irnet_get_discovery_log(ap);
+
+  /* Check if we have more item to dump */
+  if(ap->disco_index < ap->disco_number)
+    {
+      /* Write an event */
+      snprintf(event, buf_size,
+	       "Found %08x (%s) behind %08x {hints %02X-%02X}\n",
+	       ap->discoveries[ap->disco_index].daddr,
+	       ap->discoveries[ap->disco_index].info,
+	       ap->discoveries[ap->disco_index].saddr,
+	       ap->discoveries[ap->disco_index].hints[0],
+	       ap->discoveries[ap->disco_index].hints[1]);
+      DEBUG(CTRL_INFO, "Writing discovery %d : %s\n",
+	    ap->disco_index, ap->discoveries[ap->disco_index].info);
+
+      /* We have an event */
+      done_event = 1;
+      /* Next discovery */
+      ap->disco_index++;
+    }
+
+  /* Check if we have done the last item */
+  if(ap->disco_index >= ap->disco_number)
+    {
+      /* No more items : remove the log and signal termination */
+      DEBUG(CTRL_INFO, "Cleaning up log (0x%p)\n",
+	    ap->discoveries);
+      if(ap->discoveries != NULL)
+	{
+	  /* Cleanup our copy of the discovery log */
+	  kfree(ap->discoveries);
+	  ap->discoveries = NULL;
+	}
+      ap->disco_number = -1;
+    }
+
+  return done_event;
+}
+#endif /* INITIAL_DISCOVERY */
+
+/*------------------------------------------------------------------*/
+/*
+ * Read is used to get IrNET events
+ */
+static inline ssize_t
+irnet_ctrl_read(irnet_socket *	ap,
+		struct file *	file,
+		char __user *	buf,
+		size_t		count)
+{
+  DECLARE_WAITQUEUE(wait, current);
+  char		event[75];
+  ssize_t	ret = 0;
+
+  DENTER(CTRL_TRACE, "(ap=0x%p, count=%Zd)\n", ap, count);
+
+#ifdef INITIAL_DISCOVERY
+  /* Check if we have read the log */
+  if (irnet_read_discovery_log(ap, event, sizeof(event)))
+    {
+      count = min(strlen(event), count);
+      if (copy_to_user(buf, event, count))
+	{
+	  DERROR(CTRL_ERROR, "Invalid user space pointer.\n");
+	  return -EFAULT;
+	}
+
+      DEXIT(CTRL_TRACE, "\n");
+      return count;
+    }
+#endif /* INITIAL_DISCOVERY */
+
+  /* Put ourselves on the wait queue to be woken up */
+  add_wait_queue(&irnet_events.rwait, &wait);
+  set_current_state(TASK_INTERRUPTIBLE);
+  for(;;)
+    {
+      /* If there is unread events */
+      ret = 0;
+      if(ap->event_index != irnet_events.index)
+	break;
+      ret = -EAGAIN;
+      if(file->f_flags & O_NONBLOCK)
+	break;
+      ret = -ERESTARTSYS;
+      if(signal_pending(current))
+	break;
+      /* Yield and wait to be woken up */
+      schedule();
+    }
+  __set_current_state(TASK_RUNNING);
+  remove_wait_queue(&irnet_events.rwait, &wait);
+
+  /* Did we got it ? */
+  if(ret != 0)
+    {
+      /* No, return the error code */
+      DEXIT(CTRL_TRACE, " - ret %Zd\n", ret);
+      return ret;
+    }
+
+  /* Which event is it ? */
+  switch(irnet_events.log[ap->event_index].event)
+    {
+    case IRNET_DISCOVER:
+      snprintf(event, sizeof(event),
+	       "Discovered %08x (%s) behind %08x {hints %02X-%02X}\n",
+	       irnet_events.log[ap->event_index].daddr,
+	       irnet_events.log[ap->event_index].name,
+	       irnet_events.log[ap->event_index].saddr,
+	       irnet_events.log[ap->event_index].hints.byte[0],
+	       irnet_events.log[ap->event_index].hints.byte[1]);
+      break;
+    case IRNET_EXPIRE:
+      snprintf(event, sizeof(event),
+	       "Expired %08x (%s) behind %08x {hints %02X-%02X}\n",
+	       irnet_events.log[ap->event_index].daddr,
+	       irnet_events.log[ap->event_index].name,
+	       irnet_events.log[ap->event_index].saddr,
+	       irnet_events.log[ap->event_index].hints.byte[0],
+	       irnet_events.log[ap->event_index].hints.byte[1]);
+      break;
+    case IRNET_CONNECT_TO:
+      snprintf(event, sizeof(event), "Connected to %08x (%s) on ppp%d\n",
+	       irnet_events.log[ap->event_index].daddr,
+	       irnet_events.log[ap->event_index].name,
+	       irnet_events.log[ap->event_index].unit);
+      break;
+    case IRNET_CONNECT_FROM:
+      snprintf(event, sizeof(event), "Connection from %08x (%s) on ppp%d\n",
+	       irnet_events.log[ap->event_index].daddr,
+	       irnet_events.log[ap->event_index].name,
+	       irnet_events.log[ap->event_index].unit);
+      break;
+    case IRNET_REQUEST_FROM:
+      snprintf(event, sizeof(event), "Request from %08x (%s) behind %08x\n",
+	       irnet_events.log[ap->event_index].daddr,
+	       irnet_events.log[ap->event_index].name,
+	       irnet_events.log[ap->event_index].saddr);
+      break;
+    case IRNET_NOANSWER_FROM:
+      snprintf(event, sizeof(event), "No-answer from %08x (%s) on ppp%d\n",
+	       irnet_events.log[ap->event_index].daddr,
+	       irnet_events.log[ap->event_index].name,
+	       irnet_events.log[ap->event_index].unit);
+      break;
+    case IRNET_BLOCKED_LINK:
+      snprintf(event, sizeof(event), "Blocked link with %08x (%s) on ppp%d\n",
+	       irnet_events.log[ap->event_index].daddr,
+	       irnet_events.log[ap->event_index].name,
+	       irnet_events.log[ap->event_index].unit);
+      break;
+    case IRNET_DISCONNECT_FROM:
+      snprintf(event, sizeof(event), "Disconnection from %08x (%s) on ppp%d\n",
+	       irnet_events.log[ap->event_index].daddr,
+	       irnet_events.log[ap->event_index].name,
+	       irnet_events.log[ap->event_index].unit);
+      break;
+    case IRNET_DISCONNECT_TO:
+      snprintf(event, sizeof(event), "Disconnected to %08x (%s)\n",
+	       irnet_events.log[ap->event_index].daddr,
+	       irnet_events.log[ap->event_index].name);
+      break;
+    default:
+      snprintf(event, sizeof(event), "Bug\n");
+    }
+  /* Increment our event index */
+  ap->event_index = (ap->event_index + 1) % IRNET_MAX_EVENTS;
+
+  DEBUG(CTRL_INFO, "Event is :%s", event);
+
+  count = min(strlen(event), count);
+  if (copy_to_user(buf, event, count))
+    {
+      DERROR(CTRL_ERROR, "Invalid user space pointer.\n");
+      return -EFAULT;
+    }
+
+  DEXIT(CTRL_TRACE, "\n");
+  return count;
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Poll : called when someone do a select on /dev/irnet.
+ * Just check if there are new events...
+ */
+static inline unsigned int
+irnet_ctrl_poll(irnet_socket *	ap,
+		struct file *	file,
+		poll_table *	wait)
+{
+  unsigned int mask;
+
+  DENTER(CTRL_TRACE, "(ap=0x%p)\n", ap);
+
+  poll_wait(file, &irnet_events.rwait, wait);
+  mask = POLLOUT | POLLWRNORM;
+  /* If there is unread events */
+  if(ap->event_index != irnet_events.index)
+    mask |= POLLIN | POLLRDNORM;
+#ifdef INITIAL_DISCOVERY
+  if(ap->disco_number != -1)
+    {
+      /* Test if it's the first time and therefore we need to get the log */
+      if(ap->discoveries == NULL)
+	irnet_get_discovery_log(ap);
+      /* Recheck */
+      if(ap->disco_number != -1)
+	mask |= POLLIN | POLLRDNORM;
+    }
+#endif /* INITIAL_DISCOVERY */
+
+  DEXIT(CTRL_TRACE, " - mask=0x%X\n", mask);
+  return mask;
+}
+
+
+/*********************** FILESYSTEM CALLBACKS ***********************/
+/*
+ * Implement the usual open, read, write functions that will be called
+ * by the file system when some action is performed on /dev/irnet.
+ * Most of those actions will in fact be performed by "pppd" or
+ * the control channel, we just act as a redirector...
+ */
+
+/*------------------------------------------------------------------*/
+/*
+ * Open : when somebody open /dev/irnet
+ * We basically create a new instance of irnet and initialise it.
+ */
+static int
+dev_irnet_open(struct inode *	inode,
+	       struct file *	file)
+{
+  struct irnet_socket *	ap;
+  int			err;
+
+  DENTER(FS_TRACE, "(file=0x%p)\n", file);
+
+#ifdef SECURE_DEVIRNET
+  /* This could (should?) be enforced by the permissions on /dev/irnet. */
+  if(!capable(CAP_NET_ADMIN))
+    return -EPERM;
+#endif /* SECURE_DEVIRNET */
+
+  /* Allocate a private structure for this IrNET instance */
+  ap = kzalloc(sizeof(*ap), GFP_KERNEL);
+  DABORT(ap == NULL, -ENOMEM, FS_ERROR, "Can't allocate struct irnet...\n");
+
+  /* initialize the irnet structure */
+  ap->file = file;
+
+  /* PPP channel setup */
+  ap->ppp_open = 0;
+  ap->chan.private = ap;
+  ap->chan.ops = &irnet_ppp_ops;
+  ap->chan.mtu = (2048 - TTP_MAX_HEADER - 2 - PPP_HDRLEN);
+  ap->chan.hdrlen = 2 + TTP_MAX_HEADER;		/* for A/C + Max IrDA hdr */
+  /* PPP parameters */
+  ap->mru = (2048 - TTP_MAX_HEADER - 2 - PPP_HDRLEN);
+  ap->xaccm[0] = ~0U;
+  ap->xaccm[3] = 0x60000000U;
+  ap->raccm = ~0U;
+
+  /* Setup the IrDA part... */
+  err = irda_irnet_create(ap);
+  if(err)
+    {
+      DERROR(FS_ERROR, "Can't setup IrDA link...\n");
+      kfree(ap);
+
+      return err;
+    }
+
+  /* For the control channel */
+  ap->event_index = irnet_events.index;	/* Cancel all past events */
+
+  mutex_init(&ap->lock);
+
+  /* Put our stuff where we will be able to find it later */
+  file->private_data = ap;
+
+  DEXIT(FS_TRACE, " - ap=0x%p\n", ap);
+
+  return 0;
+}
+
+
+/*------------------------------------------------------------------*/
+/*
+ * Close : when somebody close /dev/irnet
+ * Destroy the instance of /dev/irnet
+ */
+static int
+dev_irnet_close(struct inode *	inode,
+		struct file *	file)
+{
+  irnet_socket *	ap = file->private_data;
+
+  DENTER(FS_TRACE, "(file=0x%p, ap=0x%p)\n",
+	 file, ap);
+  DABORT(ap == NULL, 0, FS_ERROR, "ap is NULL !!!\n");
+
+  /* Detach ourselves */
+  file->private_data = NULL;
+
+  /* Close IrDA stuff */
+  irda_irnet_destroy(ap);
+
+  /* Disconnect from the generic PPP layer if not already done */
+  if(ap->ppp_open)
+    {
+      DERROR(FS_ERROR, "Channel still registered - deregistering !\n");
+      ap->ppp_open = 0;
+      ppp_unregister_channel(&ap->chan);
+    }
+
+  kfree(ap);
+
+  DEXIT(FS_TRACE, "\n");
+  return 0;
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Write does nothing.
+ * (we receive packet from ppp_generic through ppp_irnet_send())
+ */
+static ssize_t
+dev_irnet_write(struct file *	file,
+		const char __user *buf,
+		size_t		count,
+		loff_t *	ppos)
+{
+  irnet_socket *	ap = file->private_data;
+
+  DPASS(FS_TRACE, "(file=0x%p, ap=0x%p, count=%Zd)\n",
+	file, ap, count);
+  DABORT(ap == NULL, -ENXIO, FS_ERROR, "ap is NULL !!!\n");
+
+  /* If we are connected to ppp_generic, let it handle the job */
+  if(ap->ppp_open)
+    return -EAGAIN;
+  else
+    return irnet_ctrl_write(ap, buf, count);
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Read doesn't do much either.
+ * (pppd poll us, but ultimately reads through /dev/ppp)
+ */
+static ssize_t
+dev_irnet_read(struct file *	file,
+	       char __user *	buf,
+	       size_t		count,
+	       loff_t *		ppos)
+{
+  irnet_socket *	ap = file->private_data;
+
+  DPASS(FS_TRACE, "(file=0x%p, ap=0x%p, count=%Zd)\n",
+	file, ap, count);
+  DABORT(ap == NULL, -ENXIO, FS_ERROR, "ap is NULL !!!\n");
+
+  /* If we are connected to ppp_generic, let it handle the job */
+  if(ap->ppp_open)
+    return -EAGAIN;
+  else
+    return irnet_ctrl_read(ap, file, buf, count);
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Poll : called when someone do a select on /dev/irnet
+ */
+static unsigned int
+dev_irnet_poll(struct file *	file,
+	       poll_table *	wait)
+{
+  irnet_socket *	ap = file->private_data;
+  unsigned int		mask;
+
+  DENTER(FS_TRACE, "(file=0x%p, ap=0x%p)\n",
+	 file, ap);
+
+  mask = POLLOUT | POLLWRNORM;
+  DABORT(ap == NULL, mask, FS_ERROR, "ap is NULL !!!\n");
+
+  /* If we are connected to ppp_generic, let it handle the job */
+  if(!ap->ppp_open)
+    mask |= irnet_ctrl_poll(ap, file, wait);
+
+  DEXIT(FS_TRACE, " - mask=0x%X\n", mask);
+  return mask;
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * IOCtl : Called when someone does some ioctls on /dev/irnet
+ * This is the way pppd configure us and control us while the PPP
+ * instance is active.
+ */
+static long
+dev_irnet_ioctl(
+		struct file *	file,
+		unsigned int	cmd,
+		unsigned long	arg)
+{
+  irnet_socket *	ap = file->private_data;
+  int			err;
+  int			val;
+  void __user *argp = (void __user *)arg;
+
+  DENTER(FS_TRACE, "(file=0x%p, ap=0x%p, cmd=0x%X)\n",
+	 file, ap, cmd);
+
+  /* Basic checks... */
+  DASSERT(ap != NULL, -ENXIO, PPP_ERROR, "ap is NULL...\n");
+#ifdef SECURE_DEVIRNET
+  if(!capable(CAP_NET_ADMIN))
+    return -EPERM;
+#endif /* SECURE_DEVIRNET */
+
+  err = -EFAULT;
+  switch(cmd)
+    {
+      /* Set discipline (should be N_SYNC_PPP or N_TTY) */
+    case TIOCSETD:
+      if(get_user(val, (int __user *)argp))
+	break;
+      if((val == N_SYNC_PPP) || (val == N_PPP))
+	{
+	  DEBUG(FS_INFO, "Entering PPP discipline.\n");
+	  /* PPP channel setup (ap->chan in configured in dev_irnet_open())*/
+	  if (mutex_lock_interruptible(&ap->lock))
+		  return -EINTR;
+
+	  err = ppp_register_channel(&ap->chan);
+	  if(err == 0)
+	    {
+	      /* Our ppp side is active */
+	      ap->ppp_open = 1;
+
+	      DEBUG(FS_INFO, "Trying to establish a connection.\n");
+	      /* Setup the IrDA link now - may fail... */
+	      irda_irnet_connect(ap);
+	    }
+	  else
+	    DERROR(FS_ERROR, "Can't setup PPP channel...\n");
+
+          mutex_unlock(&ap->lock);
+	}
+      else
+	{
+	  /* In theory, should be N_TTY */
+	  DEBUG(FS_INFO, "Exiting PPP discipline.\n");
+	  /* Disconnect from the generic PPP layer */
+	  if (mutex_lock_interruptible(&ap->lock))
+		  return -EINTR;
+
+	  if(ap->ppp_open)
+	    {
+	      ap->ppp_open = 0;
+	      ppp_unregister_channel(&ap->chan);
+	    }
+	  else
+	    DERROR(FS_ERROR, "Channel not registered !\n");
+	  err = 0;
+
+	  mutex_unlock(&ap->lock);
+	}
+      break;
+
+      /* Query PPP channel and unit number */
+    case PPPIOCGCHAN:
+      if (mutex_lock_interruptible(&ap->lock))
+	      return -EINTR;
+
+      if(ap->ppp_open && !put_user(ppp_channel_index(&ap->chan),
+						(int __user *)argp))
+	err = 0;
+
+      mutex_unlock(&ap->lock);
+      break;
+    case PPPIOCGUNIT:
+      if (mutex_lock_interruptible(&ap->lock))
+	      return -EINTR;
+
+      if(ap->ppp_open && !put_user(ppp_unit_number(&ap->chan),
+						(int __user *)argp))
+        err = 0;
+
+      mutex_unlock(&ap->lock);
+      break;
+
+      /* All these ioctls can be passed both directly and from ppp_generic,
+       * so we just deal with them in one place...
+       */
+    case PPPIOCGFLAGS:
+    case PPPIOCSFLAGS:
+    case PPPIOCGASYNCMAP:
+    case PPPIOCSASYNCMAP:
+    case PPPIOCGRASYNCMAP:
+    case PPPIOCSRASYNCMAP:
+    case PPPIOCGXASYNCMAP:
+    case PPPIOCSXASYNCMAP:
+    case PPPIOCGMRU:
+    case PPPIOCSMRU:
+      DEBUG(FS_INFO, "Standard PPP ioctl.\n");
+      if(!capable(CAP_NET_ADMIN))
+	err = -EPERM;
+      else {
+	if (mutex_lock_interruptible(&ap->lock))
+	      return -EINTR;
+
+	err = ppp_irnet_ioctl(&ap->chan, cmd, arg);
+
+	mutex_unlock(&ap->lock);
+      }
+      break;
+
+      /* TTY IOCTLs : Pretend that we are a tty, to keep pppd happy */
+      /* Get termios */
+    case TCGETS:
+      DEBUG(FS_INFO, "Get termios.\n");
+      if (mutex_lock_interruptible(&ap->lock))
+	      return -EINTR;
+
+#ifndef TCGETS2
+      if(!kernel_termios_to_user_termios((struct termios __user *)argp, &ap->termios))
+	err = 0;
+#else
+      if(kernel_termios_to_user_termios_1((struct termios __user *)argp, &ap->termios))
+	err = 0;
+#endif
+
+      mutex_unlock(&ap->lock);
+      break;
+      /* Set termios */
+    case TCSETSF:
+      DEBUG(FS_INFO, "Set termios.\n");
+      if (mutex_lock_interruptible(&ap->lock))
+	      return -EINTR;
+
+#ifndef TCGETS2
+      if(!user_termios_to_kernel_termios(&ap->termios, (struct termios __user *)argp))
+	err = 0;
+#else
+      if(!user_termios_to_kernel_termios_1(&ap->termios, (struct termios __user *)argp))
+	err = 0;
+#endif
+
+      mutex_unlock(&ap->lock);
+      break;
+
+      /* Set DTR/RTS */
+    case TIOCMBIS:
+    case TIOCMBIC:
+      /* Set exclusive/non-exclusive mode */
+    case TIOCEXCL:
+    case TIOCNXCL:
+      DEBUG(FS_INFO, "TTY compatibility.\n");
+      err = 0;
+      break;
+
+    case TCGETA:
+      DEBUG(FS_INFO, "TCGETA\n");
+      break;
+
+    case TCFLSH:
+      DEBUG(FS_INFO, "TCFLSH\n");
+      /* Note : this will flush buffers in PPP, so it *must* be done
+       * We should also worry that we don't accept junk here and that
+       * we get rid of our own buffers */
+#ifdef FLUSH_TO_PPP
+      if (mutex_lock_interruptible(&ap->lock))
+	      return -EINTR;
+      ppp_output_wakeup(&ap->chan);
+      mutex_unlock(&ap->lock);
+#endif /* FLUSH_TO_PPP */
+      err = 0;
+      break;
+
+    case FIONREAD:
+      DEBUG(FS_INFO, "FIONREAD\n");
+      val = 0;
+      if(put_user(val, (int __user *)argp))
+	break;
+      err = 0;
+      break;
+
+    default:
+      DERROR(FS_ERROR, "Unsupported ioctl (0x%X)\n", cmd);
+      err = -ENOTTY;
+    }
+
+  DEXIT(FS_TRACE, " - err = 0x%X\n", err);
+  return err;
+}
+
+/************************** PPP CALLBACKS **************************/
+/*
+ * This are the functions that the generic PPP driver in the kernel
+ * will call to communicate to us.
+ */
+
+/*------------------------------------------------------------------*/
+/*
+ * Prepare the ppp frame for transmission over the IrDA socket.
+ * We make sure that the header space is enough, and we change ppp header
+ * according to flags passed by pppd.
+ * This is not a callback, but just a helper function used in ppp_irnet_send()
+ */
+static inline struct sk_buff *
+irnet_prepare_skb(irnet_socket *	ap,
+		  struct sk_buff *	skb)
+{
+  unsigned char *	data;
+  int			proto;		/* PPP protocol */
+  int			islcp;		/* Protocol == LCP */
+  int			needaddr;	/* Need PPP address */
+
+  DENTER(PPP_TRACE, "(ap=0x%p, skb=0x%p)\n",
+	 ap, skb);
+
+  /* Extract PPP protocol from the frame */
+  data  = skb->data;
+  proto = (data[0] << 8) + data[1];
+
+  /* LCP packets with codes between 1 (configure-request)
+   * and 7 (code-reject) must be sent as though no options
+   * have been negotiated. */
+  islcp = (proto == PPP_LCP) && (1 <= data[2]) && (data[2] <= 7);
+
+  /* compress protocol field if option enabled */
+  if((data[0] == 0) && (ap->flags & SC_COMP_PROT) && (!islcp))
+    skb_pull(skb,1);
+
+  /* Check if we need address/control fields */
+  needaddr = 2*((ap->flags & SC_COMP_AC) == 0 || islcp);
+
+  /* Is the skb headroom large enough to contain all IrDA-headers? */
+  if((skb_headroom(skb) < (ap->max_header_size + needaddr)) ||
+      (skb_shared(skb)))
+    {
+      struct sk_buff *	new_skb;
+
+      DEBUG(PPP_INFO, "Reallocating skb\n");
+
+      /* Create a new skb */
+      new_skb = skb_realloc_headroom(skb, ap->max_header_size + needaddr);
+
+      /* We have to free the original skb anyway */
+      dev_kfree_skb(skb);
+
+      /* Did the realloc succeed ? */
+      DABORT(new_skb == NULL, NULL, PPP_ERROR, "Could not realloc skb\n");
+
+      /* Use the new skb instead */
+      skb = new_skb;
+    }
+
+  /* prepend address/control fields if necessary */
+  if(needaddr)
+    {
+      skb_push(skb, 2);
+      skb->data[0] = PPP_ALLSTATIONS;
+      skb->data[1] = PPP_UI;
+    }
+
+  DEXIT(PPP_TRACE, "\n");
+
+  return skb;
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Send a packet to the peer over the IrTTP connection.
+ * Returns 1 iff the packet was accepted.
+ * Returns 0 iff packet was not consumed.
+ * If the packet was not accepted, we will call ppp_output_wakeup
+ * at some later time to reactivate flow control in ppp_generic.
+ */
+static int
+ppp_irnet_send(struct ppp_channel *	chan,
+	       struct sk_buff *		skb)
+{
+  irnet_socket *	self = (struct irnet_socket *) chan->private;
+  int			ret;
+
+  DENTER(PPP_TRACE, "(channel=0x%p, ap/self=0x%p)\n",
+	 chan, self);
+
+  /* Check if things are somewhat valid... */
+  DASSERT(self != NULL, 0, PPP_ERROR, "Self is NULL !!!\n");
+
+  /* Check if we are connected */
+  if(!(test_bit(0, &self->ttp_open)))
+    {
+#ifdef CONNECT_IN_SEND
+      /* Let's try to connect one more time... */
+      /* Note : we won't be connected after this call, but we should be
+       * ready for next packet... */
+      /* If we are already connecting, this will fail */
+      irda_irnet_connect(self);
+#endif /* CONNECT_IN_SEND */
+
+      DEBUG(PPP_INFO, "IrTTP not ready ! (%ld-%ld)\n",
+	    self->ttp_open, self->ttp_connect);
+
+      /* Note : we can either drop the packet or block the packet.
+       *
+       * Blocking the packet allow us a better connection time,
+       * because by calling ppp_output_wakeup() we can have
+       * ppp_generic resending the LCP request immediately to us,
+       * rather than waiting for one of pppd periodic transmission of
+       * LCP request.
+       *
+       * On the other hand, if we block all packet, all those periodic
+       * transmissions of pppd accumulate in ppp_generic, creating a
+       * backlog of LCP request. When we eventually connect later on,
+       * we have to transmit all this backlog before we can connect
+       * proper (if we don't timeout before).
+       *
+       * The current strategy is as follow :
+       * While we are attempting to connect, we block packets to get
+       * a better connection time.
+       * If we fail to connect, we drain the queue and start dropping packets
+       */
+#ifdef BLOCK_WHEN_CONNECT
+      /* If we are attempting to connect */
+      if(test_bit(0, &self->ttp_connect))
+	{
+	  /* Blocking packet, ppp_generic will retry later */
+	  return 0;
+	}
+#endif /* BLOCK_WHEN_CONNECT */
+
+      /* Dropping packet, pppd will retry later */
+      dev_kfree_skb(skb);
+      return 1;
+    }
+
+  /* Check if the queue can accept any packet, otherwise block */
+  if(self->tx_flow != FLOW_START)
+    DRETURN(0, PPP_INFO, "IrTTP queue full (%d skbs)...\n",
+	    skb_queue_len(&self->tsap->tx_queue));
+
+  /* Prepare ppp frame for transmission */
+  skb = irnet_prepare_skb(self, skb);
+  DABORT(skb == NULL, 1, PPP_ERROR, "Prepare skb for Tx failed.\n");
+
+  /* Send the packet to IrTTP */
+  ret = irttp_data_request(self->tsap, skb);
+  if(ret < 0)
+    {
+      /*
+       * > IrTTPs tx queue is full, so we just have to
+       * > drop the frame! You might think that we should
+       * > just return -1 and don't deallocate the frame,
+       * > but that is dangerous since it's possible that
+       * > we have replaced the original skb with a new
+       * > one with larger headroom, and that would really
+       * > confuse do_dev_queue_xmit() in dev.c! I have
+       * > tried :-) DB
+       * Correction : we verify the flow control above (self->tx_flow),
+       * so we come here only if IrTTP doesn't like the packet (empty,
+       * too large, IrTTP not connected). In those rare cases, it's ok
+       * to drop it, we don't want to see it here again...
+       * Jean II
+       */
+      DERROR(PPP_ERROR, "IrTTP doesn't like this packet !!! (0x%X)\n", ret);
+      /* irttp_data_request already free the packet */
+    }
+
+  DEXIT(PPP_TRACE, "\n");
+  return 1;	/* Packet has been consumed */
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Take care of the ioctls that ppp_generic doesn't want to deal with...
+ * Note : we are also called from dev_irnet_ioctl().
+ */
+static int
+ppp_irnet_ioctl(struct ppp_channel *	chan,
+		unsigned int		cmd,
+		unsigned long		arg)
+{
+  irnet_socket *	ap = (struct irnet_socket *) chan->private;
+  int			err;
+  int			val;
+  u32			accm[8];
+  void __user *argp = (void __user *)arg;
+
+  DENTER(PPP_TRACE, "(channel=0x%p, ap=0x%p, cmd=0x%X)\n",
+	 chan, ap, cmd);
+
+  /* Basic checks... */
+  DASSERT(ap != NULL, -ENXIO, PPP_ERROR, "ap is NULL...\n");
+
+  err = -EFAULT;
+  switch(cmd)
+    {
+      /* PPP flags */
+    case PPPIOCGFLAGS:
+      val = ap->flags | ap->rbits;
+      if(put_user(val, (int __user *) argp))
+	break;
+      err = 0;
+      break;
+    case PPPIOCSFLAGS:
+      if(get_user(val, (int __user *) argp))
+	break;
+      ap->flags = val & ~SC_RCV_BITS;
+      ap->rbits = val & SC_RCV_BITS;
+      err = 0;
+      break;
+
+      /* Async map stuff - all dummy to please pppd */
+    case PPPIOCGASYNCMAP:
+      if(put_user(ap->xaccm[0], (u32 __user *) argp))
+	break;
+      err = 0;
+      break;
+    case PPPIOCSASYNCMAP:
+      if(get_user(ap->xaccm[0], (u32 __user *) argp))
+	break;
+      err = 0;
+      break;
+    case PPPIOCGRASYNCMAP:
+      if(put_user(ap->raccm, (u32 __user *) argp))
+	break;
+      err = 0;
+      break;
+    case PPPIOCSRASYNCMAP:
+      if(get_user(ap->raccm, (u32 __user *) argp))
+	break;
+      err = 0;
+      break;
+    case PPPIOCGXASYNCMAP:
+      if(copy_to_user(argp, ap->xaccm, sizeof(ap->xaccm)))
+	break;
+      err = 0;
+      break;
+    case PPPIOCSXASYNCMAP:
+      if(copy_from_user(accm, argp, sizeof(accm)))
+	break;
+      accm[2] &= ~0x40000000U;		/* can't escape 0x5e */
+      accm[3] |= 0x60000000U;		/* must escape 0x7d, 0x7e */
+      memcpy(ap->xaccm, accm, sizeof(ap->xaccm));
+      err = 0;
+      break;
+
+      /* Max PPP frame size */
+    case PPPIOCGMRU:
+      if(put_user(ap->mru, (int __user *) argp))
+	break;
+      err = 0;
+      break;
+    case PPPIOCSMRU:
+      if(get_user(val, (int __user *) argp))
+	break;
+      if(val < PPP_MRU)
+	val = PPP_MRU;
+      ap->mru = val;
+      err = 0;
+      break;
+
+    default:
+      DEBUG(PPP_INFO, "Unsupported ioctl (0x%X)\n", cmd);
+      err = -ENOIOCTLCMD;
+    }
+
+  DEXIT(PPP_TRACE, " - err = 0x%X\n", err);
+  return err;
+}
+
+/************************** INITIALISATION **************************/
+/*
+ * Module initialisation and all that jazz...
+ */
+
+/*------------------------------------------------------------------*/
+/*
+ * Hook our device callbacks in the filesystem, to connect our code
+ * to /dev/irnet
+ */
+static inline int __init
+ppp_irnet_init(void)
+{
+  int err = 0;
+
+  DENTER(MODULE_TRACE, "()\n");
+
+  /* Allocate ourselves as a minor in the misc range */
+  err = misc_register(&irnet_misc_device);
+
+  DEXIT(MODULE_TRACE, "\n");
+  return err;
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Cleanup at exit...
+ */
+static inline void __exit
+ppp_irnet_cleanup(void)
+{
+  DENTER(MODULE_TRACE, "()\n");
+
+  /* De-allocate /dev/irnet minor in misc range */
+  misc_deregister(&irnet_misc_device);
+
+  DEXIT(MODULE_TRACE, "\n");
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Module main entry point
+ */
+static int __init
+irnet_init(void)
+{
+  int err;
+
+  /* Initialise both parts... */
+  err = irda_irnet_init();
+  if(!err)
+    err = ppp_irnet_init();
+  return err;
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Module exit
+ */
+static void __exit
+irnet_cleanup(void)
+{
+  irda_irnet_cleanup();
+  ppp_irnet_cleanup();
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Module magic
+ */
+module_init(irnet_init);
+module_exit(irnet_cleanup);
+MODULE_AUTHOR("Jean Tourrilhes <jt@hpl.hp.com>");
+MODULE_DESCRIPTION("IrNET : Synchronous PPP over IrDA");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_CHARDEV(10, 187);