ipv6: updates to privacy addresses per RFC 4941
[linux-2.6.git] / net / ax25 / ax25_std_timer.c
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) 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>
17 #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>
26 #include <net/tcp_states.h>
27 #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
33 void ax25_std_heartbeat_expiry(ax25_cb *ax25)
34 {
35         struct sock *sk = ax25->sk;
36
37         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) <
65                             (sk->sk_rcvbuf >> 1) &&
66                             (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
81 void 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
89 void 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
96 void 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
122 void 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 }