/* * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * Copyright (C) Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk) * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) * Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de) * Copyright (C) Frederic Rible F1OAT (frible@teaser.fr) */ #include <linux/errno.h> #include <linux/types.h> #include <linux/socket.h> #include <linux/in.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/timer.h> #include <linux/string.h> #include <linux/sockios.h> #include <linux/net.h> #include <net/ax25.h> #include <linux/inet.h> #include <linux/netdevice.h> #include <linux/skbuff.h> #include <net/sock.h> #include <net/tcp_states.h> #include <asm/uaccess.h> #include <asm/system.h> #include <linux/fcntl.h> #include <linux/mm.h> #include <linux/interrupt.h> void ax25_std_heartbeat_expiry(ax25_cb *ax25) { struct sock *sk=ax25->sk; if (sk) bh_lock_sock(sk); switch (ax25->state) { case AX25_STATE_0: /* Magic here: If we listen() and a new link dies before it is accepted() it isn't 'dead' so doesn't get removed. */ if (!sk || sock_flag(sk, SOCK_DESTROY) || (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) { if (sk) { sock_hold(sk); ax25_destroy_socket(ax25); bh_unlock_sock(sk); sock_put(sk); } else ax25_destroy_socket(ax25); return; } break; case AX25_STATE_3: case AX25_STATE_4: /* * Check the state of the receive buffer. */ if (sk != NULL) { if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) && (ax25->condition & AX25_COND_OWN_RX_BUSY)) { ax25->condition &= ~AX25_COND_OWN_RX_BUSY; ax25->condition &= ~AX25_COND_ACK_PENDING; ax25_send_control(ax25, AX25_RR, AX25_POLLOFF, AX25_RESPONSE); break; } } } if (sk) bh_unlock_sock(sk); ax25_start_heartbeat(ax25); } void ax25_std_t2timer_expiry(ax25_cb *ax25) { if (ax25->condition & AX25_COND_ACK_PENDING) { ax25->condition &= ~AX25_COND_ACK_PENDING; ax25_std_timeout_response(ax25); } } void ax25_std_t3timer_expiry(ax25_cb *ax25) { ax25->n2count = 0; ax25_std_transmit_enquiry(ax25); ax25->state = AX25_STATE_4; } void ax25_std_idletimer_expiry(ax25_cb *ax25) { ax25_clear_queues(ax25); ax25->n2count = 0; ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND); ax25->state = AX25_STATE_2; ax25_calculate_t1(ax25); ax25_start_t1timer(ax25); ax25_stop_t2timer(ax25); ax25_stop_t3timer(ax25); if (ax25->sk != NULL) { bh_lock_sock(ax25->sk); ax25->sk->sk_state = TCP_CLOSE; ax25->sk->sk_err = 0; ax25->sk->sk_shutdown |= SEND_SHUTDOWN; if (!sock_flag(ax25->sk, SOCK_DEAD)) { ax25->sk->sk_state_change(ax25->sk); sock_set_flag(ax25->sk, SOCK_DEAD); } bh_unlock_sock(ax25->sk); } } void ax25_std_t1timer_expiry(ax25_cb *ax25) { switch (ax25->state) { case AX25_STATE_1: if (ax25->n2count == ax25->n2) { if (ax25->modulus == AX25_MODULUS) { ax25_disconnect(ax25, ETIMEDOUT); return; } else { ax25->modulus = AX25_MODULUS; ax25->window = ax25->ax25_dev->values[AX25_VALUES_WINDOW]; ax25->n2count = 0; ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND); } } else { ax25->n2count++; if (ax25->modulus == AX25_MODULUS) ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND); else ax25_send_control(ax25, AX25_SABME, AX25_POLLON, AX25_COMMAND); } break; case AX25_STATE_2: if (ax25->n2count == ax25->n2) { ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND); ax25_disconnect(ax25, ETIMEDOUT); return; } else { ax25->n2count++; ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND); } break; case AX25_STATE_3: ax25->n2count = 1; ax25_std_transmit_enquiry(ax25); ax25->state = AX25_STATE_4; break; case AX25_STATE_4: if (ax25->n2count == ax25->n2) { ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE); ax25_disconnect(ax25, ETIMEDOUT); return; } else { ax25->n2count++; ax25_std_transmit_enquiry(ax25); } break; } ax25_calculate_t1(ax25); ax25_start_t1timer(ax25); }