11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * This program is free software; you can redistribute it and/or modify 31da177e4SLinus Torvalds * it under the terms of the GNU General Public License as published by 41da177e4SLinus Torvalds * the Free Software Foundation; either version 2 of the License, or 51da177e4SLinus Torvalds * (at your option) any later version. 61da177e4SLinus Torvalds * 71da177e4SLinus Torvalds * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) 81da177e4SLinus Torvalds * Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de) 91da177e4SLinus Torvalds */ 101da177e4SLinus Torvalds #include <linux/errno.h> 111da177e4SLinus Torvalds #include <linux/types.h> 121da177e4SLinus Torvalds #include <linux/socket.h> 131da177e4SLinus Torvalds #include <linux/spinlock.h> 141da177e4SLinus Torvalds #include <linux/in.h> 151da177e4SLinus Torvalds #include <linux/kernel.h> 161da177e4SLinus Torvalds #include <linux/jiffies.h> 171da177e4SLinus Torvalds #include <linux/timer.h> 181da177e4SLinus Torvalds #include <linux/string.h> 191da177e4SLinus Torvalds #include <linux/sockios.h> 201da177e4SLinus Torvalds #include <linux/net.h> 21c752f073SArnaldo Carvalho de Melo #include <net/tcp_states.h> 221da177e4SLinus Torvalds #include <net/ax25.h> 231da177e4SLinus Torvalds #include <linux/inet.h> 241da177e4SLinus Torvalds #include <linux/netdevice.h> 251da177e4SLinus Torvalds #include <linux/skbuff.h> 261da177e4SLinus Torvalds #include <net/sock.h> 271da177e4SLinus Torvalds #include <asm/uaccess.h> 281da177e4SLinus Torvalds #include <asm/system.h> 291da177e4SLinus Torvalds #include <linux/fcntl.h> 301da177e4SLinus Torvalds #include <linux/mm.h> 311da177e4SLinus Torvalds #include <linux/interrupt.h> 321da177e4SLinus Torvalds 331da177e4SLinus Torvalds static void ax25_ds_timeout(unsigned long); 341da177e4SLinus Torvalds 351da177e4SLinus Torvalds /* 361da177e4SLinus Torvalds * Add DAMA slave timeout timer to timer list. 371da177e4SLinus Torvalds * Unlike the connection based timers the timeout function gets 381da177e4SLinus Torvalds * triggered every second. Please note that NET_AX25_DAMA_SLAVE_TIMEOUT 391da177e4SLinus Torvalds * (aka /proc/sys/net/ax25/{dev}/dama_slave_timeout) is still in 401da177e4SLinus Torvalds * 1/10th of a second. 411da177e4SLinus Torvalds */ 421da177e4SLinus Torvalds 431da177e4SLinus Torvalds static void ax25_ds_add_timer(ax25_dev *ax25_dev) 441da177e4SLinus Torvalds { 451da177e4SLinus Torvalds struct timer_list *t = &ax25_dev->dama.slave_timer; 461da177e4SLinus Torvalds t->data = (unsigned long) ax25_dev; 471da177e4SLinus Torvalds t->function = &ax25_ds_timeout; 481da177e4SLinus Torvalds t->expires = jiffies + HZ; 491da177e4SLinus Torvalds add_timer(t); 501da177e4SLinus Torvalds } 511da177e4SLinus Torvalds 521da177e4SLinus Torvalds void ax25_ds_del_timer(ax25_dev *ax25_dev) 531da177e4SLinus Torvalds { 541da177e4SLinus Torvalds if (ax25_dev) 551da177e4SLinus Torvalds del_timer(&ax25_dev->dama.slave_timer); 561da177e4SLinus Torvalds } 571da177e4SLinus Torvalds 581da177e4SLinus Torvalds void ax25_ds_set_timer(ax25_dev *ax25_dev) 591da177e4SLinus Torvalds { 601da177e4SLinus Torvalds if (ax25_dev == NULL) /* paranoia */ 611da177e4SLinus Torvalds return; 621da177e4SLinus Torvalds 631da177e4SLinus Torvalds del_timer(&ax25_dev->dama.slave_timer); 64e1fdb5b3SRalf Baechle ax25_dev->dama.slave_timeout = 65e1fdb5b3SRalf Baechle msecs_to_jiffies(ax25_dev->values[AX25_VALUES_DS_TIMEOUT]) / 10; 661da177e4SLinus Torvalds ax25_ds_add_timer(ax25_dev); 671da177e4SLinus Torvalds } 681da177e4SLinus Torvalds 691da177e4SLinus Torvalds /* 701da177e4SLinus Torvalds * DAMA Slave Timeout 711da177e4SLinus Torvalds * Silently discard all (slave) connections in case our master forgot us... 721da177e4SLinus Torvalds */ 731da177e4SLinus Torvalds 741da177e4SLinus Torvalds static void ax25_ds_timeout(unsigned long arg) 751da177e4SLinus Torvalds { 761da177e4SLinus Torvalds ax25_dev *ax25_dev = (struct ax25_dev *) arg; 771da177e4SLinus Torvalds ax25_cb *ax25; 781da177e4SLinus Torvalds struct hlist_node *node; 791da177e4SLinus Torvalds 801da177e4SLinus Torvalds if (ax25_dev == NULL || !ax25_dev->dama.slave) 811da177e4SLinus Torvalds return; /* Yikes! */ 821da177e4SLinus Torvalds 831da177e4SLinus Torvalds if (!ax25_dev->dama.slave_timeout || --ax25_dev->dama.slave_timeout) { 841da177e4SLinus Torvalds ax25_ds_set_timer(ax25_dev); 851da177e4SLinus Torvalds return; 861da177e4SLinus Torvalds } 871da177e4SLinus Torvalds 88c19c4b9cSRalf Baechle spin_lock(&ax25_list_lock); 891da177e4SLinus Torvalds ax25_for_each(ax25, node, &ax25_list) { 901da177e4SLinus Torvalds if (ax25->ax25_dev != ax25_dev || !(ax25->condition & AX25_COND_DAMA_MODE)) 911da177e4SLinus Torvalds continue; 921da177e4SLinus Torvalds 931da177e4SLinus Torvalds ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND); 941da177e4SLinus Torvalds ax25_disconnect(ax25, ETIMEDOUT); 951da177e4SLinus Torvalds } 96c19c4b9cSRalf Baechle spin_unlock(&ax25_list_lock); 971da177e4SLinus Torvalds 981da177e4SLinus Torvalds ax25_dev_dama_off(ax25_dev); 991da177e4SLinus Torvalds } 1001da177e4SLinus Torvalds 1011da177e4SLinus Torvalds void ax25_ds_heartbeat_expiry(ax25_cb *ax25) 1021da177e4SLinus Torvalds { 1031da177e4SLinus Torvalds struct sock *sk=ax25->sk; 1041da177e4SLinus Torvalds 1051da177e4SLinus Torvalds if (sk) 1061da177e4SLinus Torvalds bh_lock_sock(sk); 1071da177e4SLinus Torvalds 1081da177e4SLinus Torvalds switch (ax25->state) { 1091da177e4SLinus Torvalds 1101da177e4SLinus Torvalds case AX25_STATE_0: 1111da177e4SLinus Torvalds /* Magic here: If we listen() and a new link dies before it 1121da177e4SLinus Torvalds is accepted() it isn't 'dead' so doesn't get removed. */ 1131da177e4SLinus Torvalds if (!sk || sock_flag(sk, SOCK_DESTROY) || 1141da177e4SLinus Torvalds (sk->sk_state == TCP_LISTEN && 1151da177e4SLinus Torvalds sock_flag(sk, SOCK_DEAD))) { 1161da177e4SLinus Torvalds if (sk) { 1171da177e4SLinus Torvalds sock_hold(sk); 1181da177e4SLinus Torvalds ax25_destroy_socket(ax25); 1191da177e4SLinus Torvalds sock_put(sk); 1201da177e4SLinus Torvalds bh_unlock_sock(sk); 1211da177e4SLinus Torvalds } else 1221da177e4SLinus Torvalds ax25_destroy_socket(ax25); 1231da177e4SLinus Torvalds return; 1241da177e4SLinus Torvalds } 1251da177e4SLinus Torvalds break; 1261da177e4SLinus Torvalds 1271da177e4SLinus Torvalds case AX25_STATE_3: 1281da177e4SLinus Torvalds /* 1291da177e4SLinus Torvalds * Check the state of the receive buffer. 1301da177e4SLinus Torvalds */ 1311da177e4SLinus Torvalds if (sk != NULL) { 1321da177e4SLinus Torvalds if (atomic_read(&sk->sk_rmem_alloc) < 133f16f3026SEric Dumazet (sk->sk_rcvbuf >> 1) && 1341da177e4SLinus Torvalds (ax25->condition & AX25_COND_OWN_RX_BUSY)) { 1351da177e4SLinus Torvalds ax25->condition &= ~AX25_COND_OWN_RX_BUSY; 1361da177e4SLinus Torvalds ax25->condition &= ~AX25_COND_ACK_PENDING; 1371da177e4SLinus Torvalds break; 1381da177e4SLinus Torvalds } 1391da177e4SLinus Torvalds } 1401da177e4SLinus Torvalds break; 1411da177e4SLinus Torvalds } 1421da177e4SLinus Torvalds 1431da177e4SLinus Torvalds if (sk) 1441da177e4SLinus Torvalds bh_unlock_sock(sk); 1451da177e4SLinus Torvalds 1461da177e4SLinus Torvalds ax25_start_heartbeat(ax25); 1471da177e4SLinus Torvalds } 1481da177e4SLinus Torvalds 1491da177e4SLinus Torvalds /* dl1bke 960114: T3 works much like the IDLE timeout, but 1501da177e4SLinus Torvalds * gets reloaded with every frame for this 1511da177e4SLinus Torvalds * connection. 1521da177e4SLinus Torvalds */ 1531da177e4SLinus Torvalds void ax25_ds_t3timer_expiry(ax25_cb *ax25) 1541da177e4SLinus Torvalds { 1551da177e4SLinus Torvalds ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND); 1561da177e4SLinus Torvalds ax25_dama_off(ax25); 1571da177e4SLinus Torvalds ax25_disconnect(ax25, ETIMEDOUT); 1581da177e4SLinus Torvalds } 1591da177e4SLinus Torvalds 1601da177e4SLinus Torvalds /* dl1bke 960228: close the connection when IDLE expires. 1611da177e4SLinus Torvalds * unlike T3 this timer gets reloaded only on 1621da177e4SLinus Torvalds * I frames. 1631da177e4SLinus Torvalds */ 1641da177e4SLinus Torvalds void ax25_ds_idletimer_expiry(ax25_cb *ax25) 1651da177e4SLinus Torvalds { 1661da177e4SLinus Torvalds ax25_clear_queues(ax25); 1671da177e4SLinus Torvalds 1681da177e4SLinus Torvalds ax25->n2count = 0; 1691da177e4SLinus Torvalds ax25->state = AX25_STATE_2; 1701da177e4SLinus Torvalds 1711da177e4SLinus Torvalds ax25_calculate_t1(ax25); 1721da177e4SLinus Torvalds ax25_start_t1timer(ax25); 1731da177e4SLinus Torvalds ax25_stop_t3timer(ax25); 1741da177e4SLinus Torvalds 1751da177e4SLinus Torvalds if (ax25->sk != NULL) { 1761da177e4SLinus Torvalds bh_lock_sock(ax25->sk); 1771da177e4SLinus Torvalds ax25->sk->sk_state = TCP_CLOSE; 1781da177e4SLinus Torvalds ax25->sk->sk_err = 0; 1791da177e4SLinus Torvalds ax25->sk->sk_shutdown |= SEND_SHUTDOWN; 1801da177e4SLinus Torvalds if (!sock_flag(ax25->sk, SOCK_DEAD)) { 1811da177e4SLinus Torvalds ax25->sk->sk_state_change(ax25->sk); 1821da177e4SLinus Torvalds sock_set_flag(ax25->sk, SOCK_DEAD); 1831da177e4SLinus Torvalds } 1841da177e4SLinus Torvalds bh_unlock_sock(ax25->sk); 1851da177e4SLinus Torvalds } 1861da177e4SLinus Torvalds } 1871da177e4SLinus Torvalds 1881da177e4SLinus Torvalds /* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC 1891da177e4SLinus Torvalds * within the poll of any connected channel. Remember 1901da177e4SLinus Torvalds * that we are not allowed to send anything unless we 1911da177e4SLinus Torvalds * get polled by the Master. 1921da177e4SLinus Torvalds * 1931da177e4SLinus Torvalds * Thus we'll have to do parts of our T1 handling in 1941da177e4SLinus Torvalds * ax25_enquiry_response(). 1951da177e4SLinus Torvalds */ 1961da177e4SLinus Torvalds void ax25_ds_t1_timeout(ax25_cb *ax25) 1971da177e4SLinus Torvalds { 1981da177e4SLinus Torvalds switch (ax25->state) { 1991da177e4SLinus Torvalds case AX25_STATE_1: 2001da177e4SLinus Torvalds if (ax25->n2count == ax25->n2) { 2011da177e4SLinus Torvalds if (ax25->modulus == AX25_MODULUS) { 2021da177e4SLinus Torvalds ax25_disconnect(ax25, ETIMEDOUT); 2031da177e4SLinus Torvalds return; 2041da177e4SLinus Torvalds } else { 2051da177e4SLinus Torvalds ax25->modulus = AX25_MODULUS; 2061da177e4SLinus Torvalds ax25->window = ax25->ax25_dev->values[AX25_VALUES_WINDOW]; 2071da177e4SLinus Torvalds ax25->n2count = 0; 2081da177e4SLinus Torvalds ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND); 2091da177e4SLinus Torvalds } 2101da177e4SLinus Torvalds } else { 2111da177e4SLinus Torvalds ax25->n2count++; 2121da177e4SLinus Torvalds if (ax25->modulus == AX25_MODULUS) 2131da177e4SLinus Torvalds ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND); 2141da177e4SLinus Torvalds else 2151da177e4SLinus Torvalds ax25_send_control(ax25, AX25_SABME, AX25_POLLOFF, AX25_COMMAND); 2161da177e4SLinus Torvalds } 2171da177e4SLinus Torvalds break; 2181da177e4SLinus Torvalds 2191da177e4SLinus Torvalds case AX25_STATE_2: 2201da177e4SLinus Torvalds if (ax25->n2count == ax25->n2) { 2211da177e4SLinus Torvalds ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND); 2221da177e4SLinus Torvalds ax25_disconnect(ax25, ETIMEDOUT); 2231da177e4SLinus Torvalds return; 2241da177e4SLinus Torvalds } else { 2251da177e4SLinus Torvalds ax25->n2count++; 2261da177e4SLinus Torvalds } 2271da177e4SLinus Torvalds break; 2281da177e4SLinus Torvalds 2291da177e4SLinus Torvalds case AX25_STATE_3: 2301da177e4SLinus Torvalds if (ax25->n2count == ax25->n2) { 2311da177e4SLinus Torvalds ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE); 2321da177e4SLinus Torvalds ax25_disconnect(ax25, ETIMEDOUT); 2331da177e4SLinus Torvalds return; 2341da177e4SLinus Torvalds } else { 2351da177e4SLinus Torvalds ax25->n2count++; 2361da177e4SLinus Torvalds } 2371da177e4SLinus Torvalds break; 2381da177e4SLinus Torvalds } 2391da177e4SLinus Torvalds 2401da177e4SLinus Torvalds ax25_calculate_t1(ax25); 2411da177e4SLinus Torvalds ax25_start_t1timer(ax25); 2421da177e4SLinus Torvalds } 243