patch-2.1.30 linux/net/ax25/ax25_ds_timer.c

• Lines: 314
• Date: Thu Mar 20 18:17:13 1997
• Orig file: v2.1.29/linux/net/ax25/ax25_ds_timer.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.29/linux/net/ax25/ax25_ds_timer.c linux/net/ax25/ax25_ds_timer.c
@@ -0,0 +1,313 @@
+/*
+ *	AX.25 release 036
+ *
+ *	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/ NET3.038
+ *
+ *	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
+ *	AX.25 036	Jonathan(G4KLX)	Cloned from ax25_timer.c.
+ *			Joerg(DL1BKE)	Added DAMA Slave Timeout timer
+ */
+
+#include <linux/config.h>
+#if defined(CONFIG_AX25_DAMA_SLAVE)
+#include <linux/errno.h>
+#include <linux/types.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 <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+
+static void ax25_ds_timeout(unsigned long);
+
+/*
+ *	Add DAMA slave timeout timer to timer list.
+ *	Unlike the connection based timers the timeout function gets 
+ *	triggered every second. Please note that NET_AX25_DAMA_SLAVE_TIMEOUT
+ *	(aka /proc/sys/net/ax25/{dev}/dama_slave_timeout) is still in
+ *	1/10th of a second.
+ */
+
+static void ax25_ds_add_timer(ax25_dev *ax25_dev)
+{
+	struct timer_list *t = &ax25_dev->dama.slave_timer;
+	t->data		= (unsigned long) ax25_dev;
+	t->function	= &ax25_ds_timeout;
+	t->expires	= jiffies + HZ;
+	add_timer(t);
+}
+
+void ax25_ds_del_timer(ax25_dev *ax25_dev)
+{
+	if (ax25_dev) del_timer(&ax25_dev->dama.slave_timer);
+}
+
+void ax25_ds_set_timer(ax25_dev *ax25_dev)
+{
+	if (ax25_dev == NULL)		/* paranoia */
+		return;
+
+	del_timer(&ax25_dev->dama.slave_timer);
+	ax25_dev->dama.slave_timeout = ax25_dev->values[AX25_VALUES_DS_TIMEOUT] / 10;
+	ax25_ds_add_timer(ax25_dev);
+}
+
+/*
+ *	DAMA Slave Timeout
+ *	Silently discard all (slave) connections in case our master forgot us...
+ */
+
+static void ax25_ds_timeout(unsigned long arg)
+{
+	ax25_dev *ax25_dev = (struct ax25_dev *) arg;
+	ax25_cb *ax25;
+	
+	if (ax25_dev == NULL || !ax25_dev->dama.slave)
+		return;			/* Yikes! */
+	
+	if (!ax25_dev->dama.slave_timeout || --ax25_dev->dama.slave_timeout)
+	{
+		ax25_ds_set_timer(ax25_dev);
+		return;
+	}
+	
+	for (ax25=ax25_list; ax25 != NULL; ax25 = ax25->next)
+	{
+		if (ax25->ax25_dev != ax25_dev || !ax25->dama_slave)
+			continue;
+
+		ax25_link_failed(&ax25->dest_addr, ax25_dev->dev);
+		ax25_clear_queues(ax25);
+		ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
+		ax25->state = AX25_STATE_0;
+
+		if (ax25->sk != NULL)
+		{
+			SOCK_DEBUG(ax25->sk, "AX.25 DAMA Slave Timeout\n");
+			ax25->sk->state     = TCP_CLOSE;
+			ax25->sk->err       = ETIMEDOUT;
+			ax25->sk->shutdown |= SEND_SHUTDOWN;
+			if (!ax25->sk->dead)
+				ax25->sk->state_change(ax25->sk);
+			ax25->sk->dead      = 1;
+		}
+		
+		ax25_set_timer(ax25);	/* notify socket... */
+	}
+	
+	ax25_dev_dama_off(ax25_dev);
+}
+
+
+/*
+ *	AX.25 TIMER 
+ *
+ *	This routine is called every 100ms. Decrement timer by this
+ *	amount - if expired then process the event.
+ */
+void ax25_ds_timer(ax25_cb *ax25)
+{
+	switch (ax25->state) {
+		case AX25_STATE_0:
+			/* Magic here: If we listen() and a new link dies before it
+			   is accepted() it isn't 'dead' so doesn't get removed. */
+			if (ax25->sk == NULL || ax25->sk->destroy || (ax25->sk->state == TCP_LISTEN && ax25->sk->dead)) {
+				del_timer(&ax25->timer);
+				ax25_destroy_socket(ax25);
+				return;
+			}
+			break;
+
+		case AX25_STATE_3:
+		case AX25_STATE_4:
+			/*
+			 * Check the state of the receive buffer.
+			 */
+			if (ax25->sk != NULL) {
+				if (ax25->sk->rmem_alloc < (ax25->sk->rcvbuf / 2) && (ax25->condition & AX25_COND_OWN_RX_BUSY)) {
+					ax25->condition &= ~AX25_COND_OWN_RX_BUSY;
+					break;
+				}
+			}
+			break;
+
+		default:
+			break;
+	}
+	
+	/* dl1bke 960114: T3 works much like the IDLE timeout, but
+	 *                gets reloaded with every frame for this
+	 *		  connection.
+	 */
+
+	if (ax25->t3timer > 0 && --ax25->t3timer == 0) {
+		ax25_link_failed(&ax25->dest_addr, ax25->ax25_dev->dev);
+		ax25_clear_queues(ax25);
+		ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
+
+		ax25->state = AX25_STATE_0;
+		ax25_dama_off(ax25);
+
+		if (ax25->sk != NULL) {
+			SOCK_DEBUG(ax25->sk, "AX.25 T3 Timeout\n");
+			ax25->sk->state     = TCP_CLOSE;
+			ax25->sk->err       = ETIMEDOUT;
+			ax25->sk->shutdown |= SEND_SHUTDOWN;
+			if (!ax25->sk->dead)
+				ax25->sk->state_change(ax25->sk);
+			ax25->sk->dead      = 1;
+		}
+
+		ax25_set_timer(ax25);
+
+		return;
+	}
+
+	/* dl1bke 960228: close the connection when IDLE expires.
+	 *		  unlike T3 this timer gets reloaded only on
+	 *		  I frames.
+	 */
+
+	if (ax25->idletimer > 0 && --ax25->idletimer == 0) {
+		ax25_clear_queues(ax25);
+
+		ax25->n2count = 0;
+		ax25->t3timer = ax25->t3;
+
+		/* state 1 or 2 should not happen, but... */
+
+		if (ax25->state == AX25_STATE_1 || ax25->state == AX25_STATE_2)
+			ax25->state = AX25_STATE_0;
+		else
+			ax25->state = AX25_STATE_2;
+
+		ax25->t1timer = ax25->t1 = ax25_calculate_t1(ax25);
+
+		if (ax25->sk != NULL) {
+			ax25->sk->state     = TCP_CLOSE;
+			ax25->sk->err       = 0;
+			ax25->sk->shutdown |= SEND_SHUTDOWN;
+			if (!ax25->sk->dead)
+				ax25->sk->state_change(ax25->sk);
+			ax25->sk->dead      = 1;
+			ax25->sk->destroy   = 1;
+		}
+	}
+
+	ax25_set_timer(ax25);
+}
+
+/* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
+ *                within the poll of any connected channel. Remember 
+ *                that we are not allowed to send anything unless we
+ *                get polled by the Master.
+ *
+ *                Thus we'll have to do parts of our T1 handling in
+ *                ax25_enquiry_response().
+ */
+void ax25_ds_t1_timeout(ax25_cb *ax25)
+{	
+	switch (ax25->state) {
+		case AX25_STATE_1: 
+			if (ax25->n2count == ax25->n2) {
+				if (ax25->modulus == AX25_MODULUS) {
+					ax25_link_failed(&ax25->dest_addr, ax25->ax25_dev->dev);
+					ax25_clear_queues(ax25);
+					ax25->state = AX25_STATE_0;
+					if (ax25->sk != NULL) {
+						ax25->sk->state     = TCP_CLOSE;
+						ax25->sk->err       = ETIMEDOUT;
+						ax25->sk->shutdown |= SEND_SHUTDOWN;
+						if (!ax25->sk->dead)
+							ax25->sk->state_change(ax25->sk);
+						ax25->sk->dead      = 1;
+					}
+				} else {
+					ax25->modulus = AX25_MODULUS;
+					ax25->window  = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
+					ax25->n2count = 0;
+					ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
+				}
+			} else {
+				ax25->n2count++;
+				if (ax25->modulus == AX25_MODULUS)
+					ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
+				else
+					ax25_send_control(ax25, AX25_SABME, AX25_POLLOFF, AX25_COMMAND);
+			}
+			break;
+
+		case AX25_STATE_2:
+			if (ax25->n2count == ax25->n2) {
+				ax25_link_failed(&ax25->dest_addr, ax25->ax25_dev->dev);
+				ax25_clear_queues(ax25);
+				ax25->state = AX25_STATE_0;
+				ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
+
+				if (ax25->sk != NULL) {
+					ax25->sk->state     = TCP_CLOSE;
+					ax25->sk->err       = ETIMEDOUT;
+					ax25->sk->shutdown |= SEND_SHUTDOWN;
+					if (!ax25->sk->dead)
+						ax25->sk->state_change(ax25->sk);
+					ax25->sk->dead      = 1;
+				}
+			} else {
+				ax25->n2count++;
+			}
+			break;
+
+		case AX25_STATE_3: 
+			ax25->n2count = 1;
+			ax25->state   = AX25_STATE_4;
+			break;
+
+		case AX25_STATE_4:
+			if (ax25->n2count == ax25->n2) {
+				ax25_link_failed(&ax25->dest_addr, ax25->ax25_dev->dev);
+				ax25_clear_queues(ax25);
+				ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE);
+				ax25->state = AX25_STATE_0;
+				if (ax25->sk != NULL) {
+					SOCK_DEBUG(ax25->sk, "AX.25 link Failure\n");
+					ax25->sk->state     = TCP_CLOSE;
+					ax25->sk->err       = ETIMEDOUT;
+					ax25->sk->shutdown |= SEND_SHUTDOWN;
+					if (!ax25->sk->dead)
+						ax25->sk->state_change(ax25->sk);
+					ax25->sk->dead      = 1;
+				}
+			} else {
+				ax25->n2count++;
+			}
+			break;
+	}
+
+	ax25->t1timer = ax25->t1 = ax25_calculate_t1(ax25);
+
+	ax25_set_timer(ax25);
+}
+
+#endif