1 files changed, 384 insertions, 185 deletions

diff --git a/net/ax25/ax25_timer.c b/net/ax25/ax25_timer.c
index 01e7596f3..fdc871bc1 100644
--- a/net/ax25/ax25_timer.c
+++ b/net/ax25/ax25_timer.c
@@ -1,256 +1,455 @@
 /*
- *	AX.25 release 037
+ * ax25_timer.c: timer subroutines for NEW-AX.25
  *
- *	This code REQUIRES 2.1.15 or higher/ NET3.038
+ * Authors:    Jens David (DG1KJD), Matthias Welwarsky (DG2FEF), Jonathan (G4KLX
+ *             Alan Cox (GW4PTS), Joerg (DL1BKE), et al
  *
- *	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.
+ * Comment:
  *
- *	History
- *	AX.25 028a	Jonathan(G4KLX)	New state machine based on SDL diagrams.
- *	AX.25 028b	Jonathan(G4KLX)	Extracted AX25 control block from the
- *					sock structure.
- *	AX.25 029	Alan(GW4PTS)	Switched to KA9Q constant names.
- *	AX.25 031	Joerg(DL1BKE)	Added DAMA support
- *	AX.25 032	Joerg(DL1BKE)	Fixed DAMA timeout bug
- *	AX.25 033	Jonathan(G4KLX)	Modularisation functions.
- *	AX.25 035	Frederic(F1OAT)	Support for pseudo-digipeating.
- *	AX.25 036	Jonathan(G4KLX)	Split Standard and DAMA code into separate files.
- *			Joerg(DL1BKE)	Fixed DAMA Slave. We are *required* to start with
- *					standard AX.25 mode.
- *	AX.25 037	Jonathan(G4KLX)	New timer architecture.
- *                      Tomi(OH2BNS)    Fixed heartbeat expiry (check ax25_dev).
+ * Changelog:
+ *
+ * License:    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.
  */
 
+
 #include <linux/config.h>
-#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 <linux/tcp.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_heartbeat_expiry(unsigned long);
-static void ax25_t1timer_expiry(unsigned long);
-static void ax25_t2timer_expiry(unsigned long);
-static void ax25_t3timer_expiry(unsigned long);
-static void ax25_idletimer_expiry(unsigned long);
-
-void ax25_start_heartbeat(ax25_cb *ax25)
-{
-	del_timer(&ax25->timer);
+#include <net/ax25dev.h>
+#include <net/ax25.h>
 
-	ax25->timer.data     = (unsigned long)ax25;
-	ax25->timer.function = &ax25_heartbeat_expiry;
-	ax25->timer.expires  = jiffies + 5 * HZ;
+#include "ax25_core.h"
+#include "ax25_ddi.h"
+#include "ax25_in.h"
+#include "ax25_subr.h"
+#include "ax25_timer.h"
 
-	add_timer(&ax25->timer);
-}
+static void ax25_wrt_timeout(ax25_cb *);
 
-void ax25_start_t1timer(ax25_cb *ax25)
+/*
+ *	AX.25 TIMER
+ *
+ *	This routine is called every 100ms. Decrement timer by this
+ *	amount - if expired then process the event.
+ */
+void ax25_timer(ax25_cb *ax25)
 {
-	del_timer(&ax25->t1timer);
+	int wrt_timeout;
+
+	switch (ax25->state) {
+        case AX25_LISTEN:
+		/*
+		 * never kill listening sockets. let the be moved to
+		 * AX25_STATE_0 first. ax25_release() does this.
+		 */
+		return;
+
+	case AX25_STATE_0:
+		/*
+		 * don't kill if a frame signalling a state change is
+		 * still pending
+		 */
+		if (ax25->condition & AX25_COND_STATE_CHANGE)
+			break;
+
+		if (ax25->sk) {
+			/*
+			 * ax25_release() sets ax25->sk = NULL, releasing the
+			 * connection between the socket and the underlying control
+			 * structure, we handle that further down
+			 */
+
+			/* almost dead, notify socket */
+			if (!ax25->sk->dead)
+				ax25_close_socket(ax25->sk, 0);
+			break;
+		}
+
+		/*
+		 * wait a certain time before destroying the control block
+		 */
+		if (ax25->killtimer > 0 && --ax25->killtimer > 0)
+			break;
+
+		/*
+		 * if a peer exists in STATE [12], disconnect it. this handles
+		 * "connection timed out" for digipeated connections.
+		 *
+		 * else if no peer exists, destroy this control block.
+		 */
+		if (ax25->peer) {
+			if (ax25->peer->state < AX25_STATE_3)
+				ax25_destroy_cb(ax25->peer);
+			else
+				break;
+		}
+
+		ax25_destroy_cb(ax25);
+		return;
+
+	case AX25_STATE_3:
+	        write_lock(&ax25->timer_lock);
+		if (!ax25->peer && !ax25->sk && ax25->idletimer > 0 && --ax25->idletimer == 0)
+			ax25_set_cond(ax25, AX25_COND_RELEASE);
+		write_unlock(&ax25->timer_lock);
+		/* fall through */
+	case AX25_STATE_4:
+	        write_lock(&ax25->timer_lock);
+		if (ax25->condition & AX25_COND_ACK_PENDING) {
+			if (ax25->ack_timer > 0)
+				ax25->ack_timer--;
+			else
+				ax25_timeout_response(ax25);
+		}
+
+		/*
+		 * Our peer connection has seen a DISC or DM and we're about to change to
+		 * state 2. We don't DISC until we've delivered all queued data
+		 */
+		if (ax25->condition & AX25_COND_RELEASE) {
+			if (!skb_queue_len(&ax25->write_queue) && !skb_queue_len(&ax25->ack_queue)) {
+				ax25->n2count   = 1;
+				ax25->ack_timer = 0;
+				ax25_start_t1(ax25);
+				ax25_clr_cond(ax25, AX25_COND_RELEASE);
+				ax25->state = AX25_STATE_2;
+				ax25_tx_command(ax25, AX25_DISC, AX25_POLLON);
+			}
+
+		/*
+		 * Check the state of the receive buffer. This is part of the flow control
+		 * and should be done in ax25_rcvmsg();
+		 */
+		} else  if (ax25->sk && skb_queue_len(&ax25->rcv_queue)) {
+			struct sk_buff *skb;
+
+			while ((skb = skb_peek(&ax25->rcv_queue)) != NULL) {
+				if (ax25->sk->shutdown & RCV_SHUTDOWN)
+					break;
+				if (atomic_read(&ax25->sk->rmem_alloc) + skb->truesize < ax25->sk->rcvbuf) {
+					skb_dequeue(&ax25->rcv_queue);
+					sock_queue_rcv_skb(ax25->sk, skb);
+				} else
+					break;
+			}
+			if (skb == NULL) {
+				ax25_clr_cond(ax25, AX25_COND_OWN_RX_BUSY);
+				ax25_set_cond(ax25, AX25_COND_STATE_CHANGE);
+				ax25->state = AX25_STATE_4;
+				ax25_transmit_enquiry(ax25);
+			}
+		}
+		write_unlock(&ax25->timer_lock);
+		break;
+
+	default: /* state 1/2 */
+		break;
+	}
+
+	/* ax25_wrt_timout() must be called unlocked as ax25_disconnect()
+	 * sets ax25->timer_lock
+	 */
+
+	write_lock(&ax25->timer_lock);
+	wrt_timeout = (ax25->wrt_timer > 0 && --ax25->wrt_timer == 0);
+	write_unlock(&ax25->timer_lock);
+
+	if (wrt_timeout)
+		ax25_wrt_timeout(ax25);
 
-	ax25->t1timer.data     = (unsigned long)ax25;
-	ax25->t1timer.function = &ax25_t1timer_expiry;
-	ax25->t1timer.expires  = jiffies + ax25->t1;
 
-	add_timer(&ax25->t1timer);
 }
 
-void ax25_start_t2timer(ax25_cb *ax25)
+static void ax25_wrt_timeout(ax25_cb *ax25)
 {
-	del_timer(&ax25->t2timer);
+	ax25_cb *peer = ax25->peer;
+	switch (ax25->state) {
+	case AX25_STATE_1:
+		if (ax25->n2count == ax25->n2) {
+			if (ax25->seqmask == AX25_SEQMASK) {
+				ax25_disconnect(ax25, ETIMEDOUT);
+				if (ax25->sk)
+					ax25_close_socket(ax25->sk, ETIMEDOUT);
+				else if (peer) {
+					ax25_disconnect(peer, 0);
+				}
+			} else {
+				ax25->seqmask   = AX25_SEQMASK;
+				ax25->window    = ax25_dev_get_value(ax25->device, AX25_VALUES_WINDOW);
+				ax25->n2count   = 0;
+				ax25_start_t1(ax25);
+				ax25_tx_command(ax25, AX25_SABM, AX25_POLLON);
+			}
+		} else {
+			ax25->n2count++;
+			ax25_start_t1(ax25);
+			if (ax25->seqmask == AX25_SEQMASK)
+				ax25_tx_command(ax25, AX25_SABM, AX25_POLLON);
+			else
+				ax25_tx_command(ax25, AX25_SABME, AX25_POLLON);
+		}
+		break;
+
+	case AX25_STATE_2:
+		if (ax25->n2count == ax25->n2) {
+			if (ax25->sk)
+				ax25_close_socket(ax25->sk, 0);
+			ax25_disconnect(ax25, 0);
+		} else {
+			ax25->n2count++;
+			ax25_start_t1(ax25);
+			ax25_tx_command(ax25, AX25_DISC, AX25_POLLON);
+		}
+		break;
+
+	case AX25_STATE_3:
+		ax25->vs_rtt  = -1;
+		ax25->n2count = 1;
+		ax25_start_t1(ax25);
+		ax25->state = AX25_STATE_4;
+
+		/*
+		 * We are angry now.
+		 * Use CSMA. If master responds to poll, circuit will be saved
+		 * and dama_mode will be re-enabled automagically in ax25_in.c
+		 */
+		ax25_dev_set_dama(ax25->device, 0);
+		ax25_transmit_enquiry(ax25);
+		break;
+
+	case AX25_STATE_4:
+		if (ax25->n2count == ax25->n2) {
+			if (peer) {
+				ax25_set_cond(peer, AX25_COND_RELEASE);
+				ax25->killtimer  = 90 * AX25_SLOWHZ;
+			} else if (ax25->sk)
+				ax25_close_socket(ax25->sk, ETIMEDOUT);
+			ax25_disconnect(ax25, ETIMEDOUT);
+		} else {
+			ax25->n2count++;
+			ax25_transmit_enquiry(ax25);
+		}
+		break;
+	}
+}
 
-	ax25->t2timer.data     = (unsigned long)ax25;
-	ax25->t2timer.function = &ax25_t2timer_expiry;
-	ax25->t2timer.expires  = jiffies + ax25->t2;
 
-	add_timer(&ax25->t2timer);
-}
+/* -------------------------------------------------------------------- */
+
+/************************************************************************/
+/*	Module support functions follow.				*/
+/************************************************************************/
+
+static struct protocol_struct {
+	struct protocol_struct *next;
+	unsigned int pid;
+	int (*func)(struct sk_buff *, ax25_cb *);
+} *protocol_list = NULL;
+
+static struct linkfail_struct {
+	struct linkfail_struct *next;
+	void (*func)(ax25_cb *, int);
+} *linkfail_list = NULL;
 
-void ax25_start_t3timer(ax25_cb *ax25)
+static struct listen_struct {
+	struct listen_struct *next;
+	ax25_address  callsign;
+	struct net_device *dev;
+} *listen_list = NULL;
+
+int ax25_protocol_register(unsigned int pid, int (*func)(struct sk_buff *, ax25_cb *))
 {
-	del_timer(&ax25->t3timer);
+	struct protocol_struct *protocol;
+	unsigned long flags;
 
-	if (ax25->t3 > 0) {
-		ax25->t3timer.data     = (unsigned long)ax25;
-		ax25->t3timer.function = &ax25_t3timer_expiry;
-		ax25->t3timer.expires  = jiffies + ax25->t3;
+	if (pid == AX25_P_TEXT || pid == AX25_P_SEGMENT)
+		return 0;
 
-		add_timer(&ax25->t3timer);
-	}
+	if ((protocol = (struct protocol_struct *)kmalloc(sizeof(*protocol), GFP_ATOMIC)) == NULL)
+		return 0;
+
+	protocol->pid  = pid;
+	protocol->func = func;
+
+	save_flags(flags);
+	cli();
+
+	protocol->next = protocol_list;
+	protocol_list  = protocol;
+
+	restore_flags(flags);
+
+	return 1;
 }
 
-void ax25_start_idletimer(ax25_cb *ax25)
+void ax25_protocol_release(unsigned int pid)
 {
-	del_timer(&ax25->idletimer);
+	struct protocol_struct *s, *protocol = protocol_list;
+	unsigned long flags;
+
+	if (protocol == NULL)
+		return;
 
-	if (ax25->idle > 0) {
-		ax25->idletimer.data     = (unsigned long)ax25;
-		ax25->idletimer.function = &ax25_idletimer_expiry;
-		ax25->idletimer.expires  = jiffies + ax25->idle;
+	save_flags(flags);
+	cli();
 
-		add_timer(&ax25->idletimer);
+	if (protocol->pid == pid) {
+		protocol_list = protocol->next;
+		restore_flags(flags);
+		kfree(protocol);
+		return;
 	}
-}
 
-void ax25_stop_heartbeat(ax25_cb *ax25)
-{
-	del_timer(&ax25->timer);
-}
+	while (protocol != NULL && protocol->next != NULL) {
+		if (protocol->next->pid == pid) {
+			s = protocol->next;
+			protocol->next = protocol->next->next;
+			restore_flags(flags);
+			kfree(s);
+			return;
+		}
 
-void ax25_stop_t1timer(ax25_cb *ax25)
-{
-	del_timer(&ax25->t1timer);
-}
+		protocol = protocol->next;
+	}
 
-void ax25_stop_t2timer(ax25_cb *ax25)
-{
-	del_timer(&ax25->t2timer);
+	restore_flags(flags);
 }
 
-void ax25_stop_t3timer(ax25_cb *ax25)
+int ax25_linkfail_register(void (*func)(ax25_cb *, int))
 {
-	del_timer(&ax25->t3timer);
-}
+	struct linkfail_struct *linkfail;
+	unsigned long flags;
 
-void ax25_stop_idletimer(ax25_cb *ax25)
-{
-	del_timer(&ax25->idletimer);
+	if ((linkfail = (struct linkfail_struct *)kmalloc(sizeof(*linkfail), GFP_ATOMIC)) == NULL)
+		return 0;
+
+	linkfail->func = func;
+
+	save_flags(flags);
+	cli();
+
+	linkfail->next = linkfail_list;
+	linkfail_list  = linkfail;
+
+	restore_flags(flags);
+
+	return 1;
 }
 
-int ax25_t1timer_running(ax25_cb *ax25)
+void ax25_linkfail_release(void (*func)(ax25_cb *, int))
 {
-	return timer_pending(&ax25->t1timer);
+	struct linkfail_struct *s, *linkfail = linkfail_list;
+	unsigned long flags;
+
+	if (linkfail == NULL)
+		return;
+
+	save_flags(flags);
+	cli();
+
+	if (linkfail->func == func) {
+		linkfail_list = linkfail->next;
+		restore_flags(flags);
+		kfree(linkfail);
+		return;
+	}
+
+	while (linkfail != NULL && linkfail->next != NULL) {
+		if (linkfail->next->func == func) {
+			s = linkfail->next;
+			linkfail->next = linkfail->next->next;
+			restore_flags(flags);
+			kfree(s);
+			return;
+		}
+
+		linkfail = linkfail->next;
+	}
+
+	restore_flags(flags);
 }
 
-unsigned long ax25_display_timer(struct timer_list *timer)
+static char empty_addr[AX25_ADDR_LEN] = {0, 0, 0, 0, 0, 0, 0};
+
+int ax25_listen_register(ax25_address *callsign, struct net_device *dev)
 {
-	if (!timer_pending(timer))
+	ax25_cb *ax25;
+
+	ax25_addr_t addr;
+
+	addr.dcount = 0;
+	addr.src    = *callsign;
+	memcpy(&addr.dest, empty_addr, AX25_ADDR_LEN);
+
+	if (ax25_find_cb(&addr, dev) != NULL)
+		return 0;
+
+	if ((ax25 = ax25_create_cb()) == NULL)
 		return 0;
 
-	return timer->expires - jiffies;
+	ax25->addr.src = *callsign;
+
+	ax25_fillin_cb(ax25, dev);
+	ax25_insert_cb(ax25);
+
+	return 1;
 }
 
-static void ax25_heartbeat_expiry(unsigned long param)
+void ax25_listen_release(ax25_address *callsign, struct net_device *dev)
 {
-	ax25_cb *ax25 = (ax25_cb *)param;
-	int proto = AX25_PROTO_STD_SIMPLEX;
+	ax25_cb *ax25;
 
-	if (ax25->ax25_dev)
-		proto = ax25->ax25_dev->values[AX25_VALUES_PROTOCOL];
+	ax25_addr_t addr;
 
-	switch (proto) {
-		case AX25_PROTO_STD_SIMPLEX:
-		case AX25_PROTO_STD_DUPLEX:
-			ax25_std_heartbeat_expiry(ax25);
-			break;
+	addr.dcount = 0;
+	addr.src    = *callsign;
+	memcpy(&addr.dest, empty_addr, AX25_ADDR_LEN);
 
-#ifdef CONFIG_AX25_DAMA_SLAVE
-		case AX25_PROTO_DAMA_SLAVE:
-			if (ax25->ax25_dev->dama.slave)
-				ax25_ds_heartbeat_expiry(ax25);
-			else
-				ax25_std_heartbeat_expiry(ax25);
-			break;
-#endif
-	}
+	if ((ax25 = ax25_find_cb(&addr, dev)) != NULL)
+		ax25_destroy_cb(ax25);
 }
 
-static void ax25_t1timer_expiry(unsigned long param)
+int (*ax25_protocol_function(unsigned int pid))(struct sk_buff *, ax25_cb *)
 {
-	ax25_cb *ax25 = (ax25_cb *)param;
+	struct protocol_struct *protocol;
 
-	switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
-		case AX25_PROTO_STD_SIMPLEX:
-		case AX25_PROTO_STD_DUPLEX:
-			ax25_std_t1timer_expiry(ax25);
-			break;
+	for (protocol = protocol_list; protocol != NULL; protocol = protocol->next)
+		if (protocol->pid == pid)
+			return protocol->func;
 
-#ifdef CONFIG_AX25_DAMA_SLAVE
-		case AX25_PROTO_DAMA_SLAVE:
-			if (!ax25->ax25_dev->dama.slave)
-				ax25_std_t1timer_expiry(ax25);
-			break;
-#endif
-	}
+	return NULL;
 }
 
-static void ax25_t2timer_expiry(unsigned long param)
+int ax25_listen_mine(ax25_address *callsign, struct net_device *dev)
 {
-	ax25_cb *ax25 = (ax25_cb *)param;
+	struct listen_struct *listen;
 
-	switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
-		case AX25_PROTO_STD_SIMPLEX:
-		case AX25_PROTO_STD_DUPLEX:
-			ax25_std_t2timer_expiry(ax25);
-			break;
+	for (listen = listen_list; listen != NULL; listen = listen->next)
+		if (ax25cmp(&listen->callsign, callsign) == 0 && (listen->dev == dev || listen->dev == NULL))
+			return 1;
 
-#ifdef CONFIG_AX25_DAMA_SLAVE
-		case AX25_PROTO_DAMA_SLAVE:
-			if (!ax25->ax25_dev->dama.slave)
-				ax25_std_t2timer_expiry(ax25);
-			break;
-#endif
-	}
+	return 0;
 }
 
-static void ax25_t3timer_expiry(unsigned long param)
+void ax25_link_failed(ax25_cb *ax25, int reason)
 {
-	ax25_cb *ax25 = (ax25_cb *)param;
-
-	switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
-		case AX25_PROTO_STD_SIMPLEX:
-		case AX25_PROTO_STD_DUPLEX:
-			ax25_std_t3timer_expiry(ax25);
-			break;
+	struct linkfail_struct *linkfail;
 
-#ifdef CONFIG_AX25_DAMA_SLAVE
-		case AX25_PROTO_DAMA_SLAVE:
-			if (ax25->ax25_dev->dama.slave)
-				ax25_ds_t3timer_expiry(ax25);
-			else
-				ax25_std_t3timer_expiry(ax25);
-			break;
-#endif
-	}
+	for (linkfail = linkfail_list; linkfail != NULL; linkfail = linkfail->next)
+		(linkfail->func)(ax25, reason);
 }
 
-static void ax25_idletimer_expiry(unsigned long param)
+int ax25_protocol_is_registered(unsigned int pid)
 {
-	ax25_cb *ax25 = (ax25_cb *)param;
+	struct protocol_struct *protocol;
 
-	switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
-		case AX25_PROTO_STD_SIMPLEX:
-		case AX25_PROTO_STD_DUPLEX:
-			ax25_std_idletimer_expiry(ax25);
-			break;
+	for (protocol = protocol_list; protocol != NULL; protocol = protocol->next)
+		if (protocol->pid == pid)
+			return 1;
 
-#ifdef CONFIG_AX25_DAMA_SLAVE
-		case AX25_PROTO_DAMA_SLAVE:
-			if (ax25->ax25_dev->dama.slave)
-				ax25_ds_idletimer_expiry(ax25);
-			else
-				ax25_std_idletimer_expiry(ax25);
-			break;
-#endif
-	}
+	return 0;
 }