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1/*
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.
6 *
7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 * Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de)
9 */
10#include <linux/errno.h>
11#include <linux/types.h>
12#include <linux/socket.h>
13#include <linux/spinlock.h>
14#include <linux/in.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>
22#include <net/ax25.h>
23#include <linux/inet.h>
24#include <linux/netdevice.h>
25#include <linux/skbuff.h>
26#include <net/sock.h>
27#include <linux/uaccess.h>
28#include <linux/fcntl.h>
29#include <linux/mm.h>
30#include <linux/interrupt.h>
31
32static void ax25_ds_timeout(struct timer_list *);
33
34/*
35 * Add DAMA slave timeout timer to timer list.
36 * Unlike the connection based timers the timeout function gets
37 * triggered every second. Please note that NET_AX25_DAMA_SLAVE_TIMEOUT
38 * (aka /proc/sys/net/ax25/{dev}/dama_slave_timeout) is still in
39 * 1/10th of a second.
40 */
41
42void ax25_ds_setup_timer(ax25_dev *ax25_dev)
43{
44 timer_setup(&ax25_dev->dama.slave_timer, ax25_ds_timeout, 0);
45}
46
47void ax25_ds_del_timer(ax25_dev *ax25_dev)
48{
49 if (ax25_dev)
50 del_timer(&ax25_dev->dama.slave_timer);
51}
52
53void ax25_ds_set_timer(ax25_dev *ax25_dev)
54{
55 if (ax25_dev == NULL) /* paranoia */
56 return;
57
58 ax25_dev->dama.slave_timeout =
59 msecs_to_jiffies(ax25_dev->values[AX25_VALUES_DS_TIMEOUT]) / 10;
60 mod_timer(&ax25_dev->dama.slave_timer, jiffies + HZ);
61}
62
63/*
64 * DAMA Slave Timeout
65 * Silently discard all (slave) connections in case our master forgot us...
66 */
67
68static void ax25_ds_timeout(struct timer_list *t)
69{
70 ax25_dev *ax25_dev = from_timer(ax25_dev, t, dama.slave_timer);
71 ax25_cb *ax25;
72
73 if (ax25_dev == NULL || !ax25_dev->dama.slave)
74 return; /* Yikes! */
75
76 if (!ax25_dev->dama.slave_timeout || --ax25_dev->dama.slave_timeout) {
77 ax25_ds_set_timer(ax25_dev);
78 return;
79 }
80
81 spin_lock(&ax25_list_lock);
82 ax25_for_each(ax25, &ax25_list) {
83 if (ax25->ax25_dev != ax25_dev || !(ax25->condition & AX25_COND_DAMA_MODE))
84 continue;
85
86 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
87 ax25_disconnect(ax25, ETIMEDOUT);
88 }
89 spin_unlock(&ax25_list_lock);
90
91 ax25_dev_dama_off(ax25_dev);
92}
93
94void ax25_ds_heartbeat_expiry(ax25_cb *ax25)
95{
96 struct sock *sk=ax25->sk;
97
98 if (sk)
99 bh_lock_sock(sk);
100
101 switch (ax25->state) {
102
103 case AX25_STATE_0:
104 case AX25_STATE_2:
105 /* Magic here: If we listen() and a new link dies before it
106 is accepted() it isn't 'dead' so doesn't get removed. */
107 if (!sk || sock_flag(sk, SOCK_DESTROY) ||
108 (sk->sk_state == TCP_LISTEN &&
109 sock_flag(sk, SOCK_DEAD))) {
110 if (sk) {
111 sock_hold(sk);
112 ax25_destroy_socket(ax25);
113 bh_unlock_sock(sk);
114 /* Ungrab socket and destroy it */
115 sock_put(sk);
116 } else
117 ax25_destroy_socket(ax25);
118 return;
119 }
120 break;
121
122 case AX25_STATE_3:
123 /*
124 * Check the state of the receive buffer.
125 */
126 if (sk != NULL) {
127 if (atomic_read(&sk->sk_rmem_alloc) <
128 (sk->sk_rcvbuf >> 1) &&
129 (ax25->condition & AX25_COND_OWN_RX_BUSY)) {
130 ax25->condition &= ~AX25_COND_OWN_RX_BUSY;
131 ax25->condition &= ~AX25_COND_ACK_PENDING;
132 break;
133 }
134 }
135 break;
136 }
137
138 if (sk)
139 bh_unlock_sock(sk);
140
141 ax25_start_heartbeat(ax25);
142}
143
144/* dl1bke 960114: T3 works much like the IDLE timeout, but
145 * gets reloaded with every frame for this
146 * connection.
147 */
148void ax25_ds_t3timer_expiry(ax25_cb *ax25)
149{
150 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
151 ax25_dama_off(ax25);
152 ax25_disconnect(ax25, ETIMEDOUT);
153}
154
155/* dl1bke 960228: close the connection when IDLE expires.
156 * unlike T3 this timer gets reloaded only on
157 * I frames.
158 */
159void ax25_ds_idletimer_expiry(ax25_cb *ax25)
160{
161 ax25_clear_queues(ax25);
162
163 ax25->n2count = 0;
164 ax25->state = AX25_STATE_2;
165
166 ax25_calculate_t1(ax25);
167 ax25_start_t1timer(ax25);
168 ax25_stop_t3timer(ax25);
169
170 if (ax25->sk != NULL) {
171 bh_lock_sock(ax25->sk);
172 ax25->sk->sk_state = TCP_CLOSE;
173 ax25->sk->sk_err = 0;
174 ax25->sk->sk_shutdown |= SEND_SHUTDOWN;
175 if (!sock_flag(ax25->sk, SOCK_DEAD)) {
176 ax25->sk->sk_state_change(ax25->sk);
177 sock_set_flag(ax25->sk, SOCK_DEAD);
178 }
179 bh_unlock_sock(ax25->sk);
180 }
181}
182
183/* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
184 * within the poll of any connected channel. Remember
185 * that we are not allowed to send anything unless we
186 * get polled by the Master.
187 *
188 * Thus we'll have to do parts of our T1 handling in
189 * ax25_enquiry_response().
190 */
191void ax25_ds_t1_timeout(ax25_cb *ax25)
192{
193 switch (ax25->state) {
194 case AX25_STATE_1:
195 if (ax25->n2count == ax25->n2) {
196 if (ax25->modulus == AX25_MODULUS) {
197 ax25_disconnect(ax25, ETIMEDOUT);
198 return;
199 } else {
200 ax25->modulus = AX25_MODULUS;
201 ax25->window = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
202 ax25->n2count = 0;
203 ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
204 }
205 } else {
206 ax25->n2count++;
207 if (ax25->modulus == AX25_MODULUS)
208 ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
209 else
210 ax25_send_control(ax25, AX25_SABME, AX25_POLLOFF, AX25_COMMAND);
211 }
212 break;
213
214 case AX25_STATE_2:
215 if (ax25->n2count == ax25->n2) {
216 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
217 if (!sock_flag(ax25->sk, SOCK_DESTROY))
218 ax25_disconnect(ax25, ETIMEDOUT);
219 return;
220 } else {
221 ax25->n2count++;
222 }
223 break;
224
225 case AX25_STATE_3:
226 if (ax25->n2count == ax25->n2) {
227 ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE);
228 ax25_disconnect(ax25, ETIMEDOUT);
229 return;
230 } else {
231 ax25->n2count++;
232 }
233 break;
234 }
235
236 ax25_calculate_t1(ax25);
237 ax25_start_t1timer(ax25);
238}
1/*
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.
6 *
7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 * Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de)
9 */
10#include <linux/errno.h>
11#include <linux/types.h>
12#include <linux/socket.h>
13#include <linux/spinlock.h>
14#include <linux/in.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>
22#include <net/ax25.h>
23#include <linux/inet.h>
24#include <linux/netdevice.h>
25#include <linux/skbuff.h>
26#include <net/sock.h>
27#include <asm/uaccess.h>
28#include <linux/fcntl.h>
29#include <linux/mm.h>
30#include <linux/interrupt.h>
31
32static void ax25_ds_timeout(unsigned long);
33
34/*
35 * Add DAMA slave timeout timer to timer list.
36 * Unlike the connection based timers the timeout function gets
37 * triggered every second. Please note that NET_AX25_DAMA_SLAVE_TIMEOUT
38 * (aka /proc/sys/net/ax25/{dev}/dama_slave_timeout) is still in
39 * 1/10th of a second.
40 */
41
42void ax25_ds_setup_timer(ax25_dev *ax25_dev)
43{
44 setup_timer(&ax25_dev->dama.slave_timer, ax25_ds_timeout,
45 (unsigned long)ax25_dev);
46}
47
48void ax25_ds_del_timer(ax25_dev *ax25_dev)
49{
50 if (ax25_dev)
51 del_timer(&ax25_dev->dama.slave_timer);
52}
53
54void ax25_ds_set_timer(ax25_dev *ax25_dev)
55{
56 if (ax25_dev == NULL) /* paranoia */
57 return;
58
59 ax25_dev->dama.slave_timeout =
60 msecs_to_jiffies(ax25_dev->values[AX25_VALUES_DS_TIMEOUT]) / 10;
61 mod_timer(&ax25_dev->dama.slave_timer, jiffies + HZ);
62}
63
64/*
65 * DAMA Slave Timeout
66 * Silently discard all (slave) connections in case our master forgot us...
67 */
68
69static void ax25_ds_timeout(unsigned long arg)
70{
71 ax25_dev *ax25_dev = (struct ax25_dev *) arg;
72 ax25_cb *ax25;
73 struct hlist_node *node;
74
75 if (ax25_dev == NULL || !ax25_dev->dama.slave)
76 return; /* Yikes! */
77
78 if (!ax25_dev->dama.slave_timeout || --ax25_dev->dama.slave_timeout) {
79 ax25_ds_set_timer(ax25_dev);
80 return;
81 }
82
83 spin_lock(&ax25_list_lock);
84 ax25_for_each(ax25, node, &ax25_list) {
85 if (ax25->ax25_dev != ax25_dev || !(ax25->condition & AX25_COND_DAMA_MODE))
86 continue;
87
88 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
89 ax25_disconnect(ax25, ETIMEDOUT);
90 }
91 spin_unlock(&ax25_list_lock);
92
93 ax25_dev_dama_off(ax25_dev);
94}
95
96void ax25_ds_heartbeat_expiry(ax25_cb *ax25)
97{
98 struct sock *sk=ax25->sk;
99
100 if (sk)
101 bh_lock_sock(sk);
102
103 switch (ax25->state) {
104
105 case AX25_STATE_0:
106 /* Magic here: If we listen() and a new link dies before it
107 is accepted() it isn't 'dead' so doesn't get removed. */
108 if (!sk || sock_flag(sk, SOCK_DESTROY) ||
109 (sk->sk_state == TCP_LISTEN &&
110 sock_flag(sk, SOCK_DEAD))) {
111 if (sk) {
112 sock_hold(sk);
113 ax25_destroy_socket(ax25);
114 bh_unlock_sock(sk);
115 sock_put(sk);
116 } else
117 ax25_destroy_socket(ax25);
118 return;
119 }
120 break;
121
122 case AX25_STATE_3:
123 /*
124 * Check the state of the receive buffer.
125 */
126 if (sk != NULL) {
127 if (atomic_read(&sk->sk_rmem_alloc) <
128 (sk->sk_rcvbuf >> 1) &&
129 (ax25->condition & AX25_COND_OWN_RX_BUSY)) {
130 ax25->condition &= ~AX25_COND_OWN_RX_BUSY;
131 ax25->condition &= ~AX25_COND_ACK_PENDING;
132 break;
133 }
134 }
135 break;
136 }
137
138 if (sk)
139 bh_unlock_sock(sk);
140
141 ax25_start_heartbeat(ax25);
142}
143
144/* dl1bke 960114: T3 works much like the IDLE timeout, but
145 * gets reloaded with every frame for this
146 * connection.
147 */
148void ax25_ds_t3timer_expiry(ax25_cb *ax25)
149{
150 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
151 ax25_dama_off(ax25);
152 ax25_disconnect(ax25, ETIMEDOUT);
153}
154
155/* dl1bke 960228: close the connection when IDLE expires.
156 * unlike T3 this timer gets reloaded only on
157 * I frames.
158 */
159void ax25_ds_idletimer_expiry(ax25_cb *ax25)
160{
161 ax25_clear_queues(ax25);
162
163 ax25->n2count = 0;
164 ax25->state = AX25_STATE_2;
165
166 ax25_calculate_t1(ax25);
167 ax25_start_t1timer(ax25);
168 ax25_stop_t3timer(ax25);
169
170 if (ax25->sk != NULL) {
171 bh_lock_sock(ax25->sk);
172 ax25->sk->sk_state = TCP_CLOSE;
173 ax25->sk->sk_err = 0;
174 ax25->sk->sk_shutdown |= SEND_SHUTDOWN;
175 if (!sock_flag(ax25->sk, SOCK_DEAD)) {
176 ax25->sk->sk_state_change(ax25->sk);
177 sock_set_flag(ax25->sk, SOCK_DEAD);
178 }
179 bh_unlock_sock(ax25->sk);
180 }
181}
182
183/* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
184 * within the poll of any connected channel. Remember
185 * that we are not allowed to send anything unless we
186 * get polled by the Master.
187 *
188 * Thus we'll have to do parts of our T1 handling in
189 * ax25_enquiry_response().
190 */
191void ax25_ds_t1_timeout(ax25_cb *ax25)
192{
193 switch (ax25->state) {
194 case AX25_STATE_1:
195 if (ax25->n2count == ax25->n2) {
196 if (ax25->modulus == AX25_MODULUS) {
197 ax25_disconnect(ax25, ETIMEDOUT);
198 return;
199 } else {
200 ax25->modulus = AX25_MODULUS;
201 ax25->window = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
202 ax25->n2count = 0;
203 ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
204 }
205 } else {
206 ax25->n2count++;
207 if (ax25->modulus == AX25_MODULUS)
208 ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
209 else
210 ax25_send_control(ax25, AX25_SABME, AX25_POLLOFF, AX25_COMMAND);
211 }
212 break;
213
214 case AX25_STATE_2:
215 if (ax25->n2count == ax25->n2) {
216 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
217 ax25_disconnect(ax25, ETIMEDOUT);
218 return;
219 } else {
220 ax25->n2count++;
221 }
222 break;
223
224 case AX25_STATE_3:
225 if (ax25->n2count == ax25->n2) {
226 ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE);
227 ax25_disconnect(ax25, ETIMEDOUT);
228 return;
229 } else {
230 ax25->n2count++;
231 }
232 break;
233 }
234
235 ax25_calculate_t1(ax25);
236 ax25_start_t1timer(ax25);
237}