2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 * Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de)
10 #include <linux/errno.h>
11 #include <linux/types.h>
12 #include <linux/socket.h>
13 #include <linux/spinlock.h>
15 #include <linux/kernel.h>
16 #include <linux/jiffies.h>
17 #include <linux/timer.h>
18 #include <linux/string.h>
19 #include <linux/sockios.h>
20 #include <linux/net.h>
21 #include <net/tcp_states.h>
23 #include <linux/inet.h>
24 #include <linux/netdevice.h>
25 #include <linux/skbuff.h>
27 #include <asm/uaccess.h>
28 #include <asm/system.h>
29 #include <linux/fcntl.h>
31 #include <linux/interrupt.h>
33 static void ax25_ds_timeout(unsigned long);
36 * Add DAMA slave timeout timer to timer list.
37 * Unlike the connection based timers the timeout function gets
38 * triggered every second. Please note that NET_AX25_DAMA_SLAVE_TIMEOUT
39 * (aka /proc/sys/net/ax25/{dev}/dama_slave_timeout) is still in
43 static void ax25_ds_add_timer(ax25_dev
*ax25_dev
)
45 struct timer_list
*t
= &ax25_dev
->dama
.slave_timer
;
46 t
->data
= (unsigned long) ax25_dev
;
47 t
->function
= &ax25_ds_timeout
;
48 t
->expires
= jiffies
+ HZ
;
52 void ax25_ds_del_timer(ax25_dev
*ax25_dev
)
55 del_timer(&ax25_dev
->dama
.slave_timer
);
58 void ax25_ds_set_timer(ax25_dev
*ax25_dev
)
60 if (ax25_dev
== NULL
) /* paranoia */
63 del_timer(&ax25_dev
->dama
.slave_timer
);
64 ax25_dev
->dama
.slave_timeout
=
65 msecs_to_jiffies(ax25_dev
->values
[AX25_VALUES_DS_TIMEOUT
]) / 10;
66 ax25_ds_add_timer(ax25_dev
);
71 * Silently discard all (slave) connections in case our master forgot us...
74 static void ax25_ds_timeout(unsigned long arg
)
76 ax25_dev
*ax25_dev
= (struct ax25_dev
*) arg
;
78 struct hlist_node
*node
;
80 if (ax25_dev
== NULL
|| !ax25_dev
->dama
.slave
)
83 if (!ax25_dev
->dama
.slave_timeout
|| --ax25_dev
->dama
.slave_timeout
) {
84 ax25_ds_set_timer(ax25_dev
);
88 spin_lock_bh(&ax25_list_lock
);
89 ax25_for_each(ax25
, node
, &ax25_list
) {
90 if (ax25
->ax25_dev
!= ax25_dev
|| !(ax25
->condition
& AX25_COND_DAMA_MODE
))
93 ax25_send_control(ax25
, AX25_DISC
, AX25_POLLON
, AX25_COMMAND
);
94 ax25_disconnect(ax25
, ETIMEDOUT
);
96 spin_unlock_bh(&ax25_list_lock
);
98 ax25_dev_dama_off(ax25_dev
);
101 void ax25_ds_heartbeat_expiry(ax25_cb
*ax25
)
103 struct sock
*sk
=ax25
->sk
;
108 switch (ax25
->state
) {
111 /* Magic here: If we listen() and a new link dies before it
112 is accepted() it isn't 'dead' so doesn't get removed. */
113 if (!sk
|| sock_flag(sk
, SOCK_DESTROY
) ||
114 (sk
->sk_state
== TCP_LISTEN
&&
115 sock_flag(sk
, SOCK_DEAD
))) {
118 ax25_destroy_socket(ax25
);
122 ax25_destroy_socket(ax25
);
129 * Check the state of the receive buffer.
132 if (atomic_read(&sk
->sk_rmem_alloc
) <
133 (sk
->sk_rcvbuf
/ 2) &&
134 (ax25
->condition
& AX25_COND_OWN_RX_BUSY
)) {
135 ax25
->condition
&= ~AX25_COND_OWN_RX_BUSY
;
136 ax25
->condition
&= ~AX25_COND_ACK_PENDING
;
146 ax25_start_heartbeat(ax25
);
149 /* dl1bke 960114: T3 works much like the IDLE timeout, but
150 * gets reloaded with every frame for this
153 void ax25_ds_t3timer_expiry(ax25_cb
*ax25
)
155 ax25_send_control(ax25
, AX25_DISC
, AX25_POLLON
, AX25_COMMAND
);
157 ax25_disconnect(ax25
, ETIMEDOUT
);
160 /* dl1bke 960228: close the connection when IDLE expires.
161 * unlike T3 this timer gets reloaded only on
164 void ax25_ds_idletimer_expiry(ax25_cb
*ax25
)
166 ax25_clear_queues(ax25
);
169 ax25
->state
= AX25_STATE_2
;
171 ax25_calculate_t1(ax25
);
172 ax25_start_t1timer(ax25
);
173 ax25_stop_t3timer(ax25
);
175 if (ax25
->sk
!= NULL
) {
176 bh_lock_sock(ax25
->sk
);
177 ax25
->sk
->sk_state
= TCP_CLOSE
;
178 ax25
->sk
->sk_err
= 0;
179 ax25
->sk
->sk_shutdown
|= SEND_SHUTDOWN
;
180 if (!sock_flag(ax25
->sk
, SOCK_DEAD
)) {
181 ax25
->sk
->sk_state_change(ax25
->sk
);
182 sock_set_flag(ax25
->sk
, SOCK_DEAD
);
184 bh_unlock_sock(ax25
->sk
);
188 /* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
189 * within the poll of any connected channel. Remember
190 * that we are not allowed to send anything unless we
191 * get polled by the Master.
193 * Thus we'll have to do parts of our T1 handling in
194 * ax25_enquiry_response().
196 void ax25_ds_t1_timeout(ax25_cb
*ax25
)
198 switch (ax25
->state
) {
200 if (ax25
->n2count
== ax25
->n2
) {
201 if (ax25
->modulus
== AX25_MODULUS
) {
202 ax25_disconnect(ax25
, ETIMEDOUT
);
205 ax25
->modulus
= AX25_MODULUS
;
206 ax25
->window
= ax25
->ax25_dev
->values
[AX25_VALUES_WINDOW
];
208 ax25_send_control(ax25
, AX25_SABM
, AX25_POLLOFF
, AX25_COMMAND
);
212 if (ax25
->modulus
== AX25_MODULUS
)
213 ax25_send_control(ax25
, AX25_SABM
, AX25_POLLOFF
, AX25_COMMAND
);
215 ax25_send_control(ax25
, AX25_SABME
, AX25_POLLOFF
, AX25_COMMAND
);
220 if (ax25
->n2count
== ax25
->n2
) {
221 ax25_send_control(ax25
, AX25_DISC
, AX25_POLLON
, AX25_COMMAND
);
222 ax25_disconnect(ax25
, ETIMEDOUT
);
230 if (ax25
->n2count
== ax25
->n2
) {
231 ax25_send_control(ax25
, AX25_DM
, AX25_POLLON
, AX25_RESPONSE
);
232 ax25_disconnect(ax25
, ETIMEDOUT
);
240 ax25_calculate_t1(ax25
);
241 ax25_start_t1timer(ax25
);