blob: 96e4b9273250918b4a60fdcc9ccce00b79090827 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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) Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
8 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
9 * Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de)
10 * Copyright (C) Frederic Rible F1OAT (frible@teaser.fr)
11 */
12#include <linux/errno.h>
13#include <linux/types.h>
14#include <linux/socket.h>
15#include <linux/in.h>
16#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/timer.h>
18#include <linux/string.h>
19#include <linux/sockios.h>
20#include <linux/net.h>
21#include <net/ax25.h>
22#include <linux/inet.h>
23#include <linux/netdevice.h>
24#include <linux/skbuff.h>
25#include <net/sock.h>
Arnaldo Carvalho de Meloc752f072005-08-09 20:08:28 -070026#include <net/tcp_states.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <asm/uaccess.h>
28#include <asm/system.h>
29#include <linux/fcntl.h>
30#include <linux/mm.h>
31#include <linux/interrupt.h>
32
33void ax25_std_heartbeat_expiry(ax25_cb *ax25)
34{
Eric Dumazetf16f3022008-01-13 22:29:41 -080035 struct sock *sk = ax25->sk;
YOSHIFUJI Hideaki528930b2007-02-09 23:24:31 +090036
Linus Torvalds1da177e2005-04-16 15:20:36 -070037 if (sk)
38 bh_lock_sock(sk);
39
40 switch (ax25->state) {
41 case AX25_STATE_0:
42 /* Magic here: If we listen() and a new link dies before it
43 is accepted() it isn't 'dead' so doesn't get removed. */
44 if (!sk || sock_flag(sk, SOCK_DESTROY) ||
45 (sk->sk_state == TCP_LISTEN &&
46 sock_flag(sk, SOCK_DEAD))) {
47 if (sk) {
48 sock_hold(sk);
49 ax25_destroy_socket(ax25);
50 bh_unlock_sock(sk);
51 sock_put(sk);
52 } else
53 ax25_destroy_socket(ax25);
54 return;
55 }
56 break;
57
58 case AX25_STATE_3:
59 case AX25_STATE_4:
60 /*
61 * Check the state of the receive buffer.
62 */
63 if (sk != NULL) {
64 if (atomic_read(&sk->sk_rmem_alloc) <
Eric Dumazetf16f3022008-01-13 22:29:41 -080065 (sk->sk_rcvbuf >> 1) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 (ax25->condition & AX25_COND_OWN_RX_BUSY)) {
67 ax25->condition &= ~AX25_COND_OWN_RX_BUSY;
68 ax25->condition &= ~AX25_COND_ACK_PENDING;
69 ax25_send_control(ax25, AX25_RR, AX25_POLLOFF, AX25_RESPONSE);
70 break;
71 }
72 }
73 }
74
75 if (sk)
76 bh_unlock_sock(sk);
77
78 ax25_start_heartbeat(ax25);
79}
80
81void ax25_std_t2timer_expiry(ax25_cb *ax25)
82{
83 if (ax25->condition & AX25_COND_ACK_PENDING) {
84 ax25->condition &= ~AX25_COND_ACK_PENDING;
85 ax25_std_timeout_response(ax25);
86 }
87}
88
89void ax25_std_t3timer_expiry(ax25_cb *ax25)
90{
91 ax25->n2count = 0;
92 ax25_std_transmit_enquiry(ax25);
93 ax25->state = AX25_STATE_4;
94}
95
96void ax25_std_idletimer_expiry(ax25_cb *ax25)
97{
98 ax25_clear_queues(ax25);
99
100 ax25->n2count = 0;
101 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
102 ax25->state = AX25_STATE_2;
103
104 ax25_calculate_t1(ax25);
105 ax25_start_t1timer(ax25);
106 ax25_stop_t2timer(ax25);
107 ax25_stop_t3timer(ax25);
108
109 if (ax25->sk != NULL) {
110 bh_lock_sock(ax25->sk);
111 ax25->sk->sk_state = TCP_CLOSE;
112 ax25->sk->sk_err = 0;
113 ax25->sk->sk_shutdown |= SEND_SHUTDOWN;
114 if (!sock_flag(ax25->sk, SOCK_DEAD)) {
115 ax25->sk->sk_state_change(ax25->sk);
116 sock_set_flag(ax25->sk, SOCK_DEAD);
117 }
118 bh_unlock_sock(ax25->sk);
119 }
120}
121
122void ax25_std_t1timer_expiry(ax25_cb *ax25)
123{
124 switch (ax25->state) {
125 case AX25_STATE_1:
126 if (ax25->n2count == ax25->n2) {
127 if (ax25->modulus == AX25_MODULUS) {
128 ax25_disconnect(ax25, ETIMEDOUT);
129 return;
130 } else {
131 ax25->modulus = AX25_MODULUS;
132 ax25->window = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
133 ax25->n2count = 0;
134 ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND);
135 }
136 } else {
137 ax25->n2count++;
138 if (ax25->modulus == AX25_MODULUS)
139 ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND);
140 else
141 ax25_send_control(ax25, AX25_SABME, AX25_POLLON, AX25_COMMAND);
142 }
143 break;
144
145 case AX25_STATE_2:
146 if (ax25->n2count == ax25->n2) {
147 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
148 ax25_disconnect(ax25, ETIMEDOUT);
149 return;
150 } else {
151 ax25->n2count++;
152 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
153 }
154 break;
155
156 case AX25_STATE_3:
157 ax25->n2count = 1;
158 ax25_std_transmit_enquiry(ax25);
159 ax25->state = AX25_STATE_4;
160 break;
161
162 case AX25_STATE_4:
163 if (ax25->n2count == ax25->n2) {
164 ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE);
165 ax25_disconnect(ax25, ETIMEDOUT);
166 return;
167 } else {
168 ax25->n2count++;
169 ax25_std_transmit_enquiry(ax25);
170 }
171 break;
172 }
173
174 ax25_calculate_t1(ax25);
175 ax25_start_t1timer(ax25);
176}