// SPDX-License-Identifier: GPL-2.0-or-later /* * * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) * Copyright (C) 2002 Ralf Baechle DO1GRB (ralf@gnu.org) */ #include <linux/errno.h> #include <linux/types.h> #include <linux/socket.h> #include <linux/in.h> #include <linux/kernel.h> #include <linux/jiffies.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 <linux/uaccess.h> #include <linux/fcntl.h> #include <linux/mm.h> #include <linux/interrupt.h> #include <net/netrom.h> static void nr_heartbeat_expiry(struct timer_list *); static void nr_t1timer_expiry(struct timer_list *); static void nr_t2timer_expiry(struct timer_list *); static void nr_t4timer_expiry(struct timer_list *); static void nr_idletimer_expiry(struct timer_list *); void nr_init_timers(struct sock *sk) { struct nr_sock *nr = nr_sk(sk); timer_setup(&nr->t1timer, nr_t1timer_expiry, 0); timer_setup(&nr->t2timer, nr_t2timer_expiry, 0); timer_setup(&nr->t4timer, nr_t4timer_expiry, 0); timer_setup(&nr->idletimer, nr_idletimer_expiry, 0); /* initialized by sock_init_data */ sk->sk_timer.function = nr_heartbeat_expiry; } void nr_start_t1timer(struct sock *sk) { struct nr_sock *nr = nr_sk(sk); sk_reset_timer(sk, &nr->t1timer, jiffies + nr->t1); } void nr_start_t2timer(struct sock *sk) { struct nr_sock *nr = nr_sk(sk); sk_reset_timer(sk, &nr->t2timer, jiffies + nr->t2); } void nr_start_t4timer(struct sock *sk) { struct nr_sock *nr = nr_sk(sk); sk_reset_timer(sk, &nr->t4timer, jiffies + nr->t4); } void nr_start_idletimer(struct sock *sk) { struct nr_sock *nr = nr_sk(sk); if (nr->idle > 0) sk_reset_timer(sk, &nr->idletimer, jiffies + nr->idle); } void nr_start_heartbeat(struct sock *sk) { sk_reset_timer(sk, &sk->sk_timer, jiffies + 5 * HZ); } void nr_stop_t1timer(struct sock *sk) { sk_stop_timer(sk, &nr_sk(sk)->t1timer); } void nr_stop_t2timer(struct sock *sk) { sk_stop_timer(sk, &nr_sk(sk)->t2timer); } void nr_stop_t4timer(struct sock *sk) { sk_stop_timer(sk, &nr_sk(sk)->t4timer); } void nr_stop_idletimer(struct sock *sk) { sk_stop_timer(sk, &nr_sk(sk)->idletimer); } void nr_stop_heartbeat(struct sock *sk) { sk_stop_timer(sk, &sk->sk_timer); } int nr_t1timer_running(struct sock *sk) { return timer_pending(&nr_sk(sk)->t1timer); } static void nr_heartbeat_expiry(struct timer_list *t) { struct sock *sk = from_timer(sk, t, sk_timer); struct nr_sock *nr = nr_sk(sk); bh_lock_sock(sk); switch (nr->state) { case NR_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 (sock_flag(sk, SOCK_DESTROY) || (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) { bh_unlock_sock(sk); nr_destroy_socket(sk); goto out; } break; case NR_STATE_3: /* * Check for the state of the receive buffer. */ if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) && (nr->condition & NR_COND_OWN_RX_BUSY)) { nr->condition &= ~NR_COND_OWN_RX_BUSY; nr->condition &= ~NR_COND_ACK_PENDING; nr->vl = nr->vr; nr_write_internal(sk, NR_INFOACK); break; } break; } nr_start_heartbeat(sk); bh_unlock_sock(sk); out: sock_put(sk); } static void nr_t2timer_expiry(struct timer_list *t) { struct nr_sock *nr = from_timer(nr, t, t2timer); struct sock *sk = &nr->sock; bh_lock_sock(sk); if (nr->condition & NR_COND_ACK_PENDING) { nr->condition &= ~NR_COND_ACK_PENDING; nr_enquiry_response(sk); } bh_unlock_sock(sk); sock_put(sk); } static void nr_t4timer_expiry(struct timer_list *t) { struct nr_sock *nr = from_timer(nr, t, t4timer); struct sock *sk = &nr->sock; bh_lock_sock(sk); nr_sk(sk)->condition &= ~NR_COND_PEER_RX_BUSY; bh_unlock_sock(sk); sock_put(sk); } static void nr_idletimer_expiry(struct timer_list *t) { struct nr_sock *nr = from_timer(nr, t, idletimer); struct sock *sk = &nr->sock; bh_lock_sock(sk); nr_clear_queues(sk); nr->n2count = 0; nr_write_internal(sk, NR_DISCREQ); nr->state = NR_STATE_2; nr_start_t1timer(sk); nr_stop_t2timer(sk); nr_stop_t4timer(sk); sk->sk_state = TCP_CLOSE; sk->sk_err = 0; sk->sk_shutdown |= SEND_SHUTDOWN; if (!sock_flag(sk, SOCK_DEAD)) { sk->sk_state_change(sk); sock_set_flag(sk, SOCK_DEAD); } bh_unlock_sock(sk); sock_put(sk); } static void nr_t1timer_expiry(struct timer_list *t) { struct nr_sock *nr = from_timer(nr, t, t1timer); struct sock *sk = &nr->sock; bh_lock_sock(sk); switch (nr->state) { case NR_STATE_1: if (nr->n2count == nr->n2) { nr_disconnect(sk, ETIMEDOUT); goto out; } else { nr->n2count++; nr_write_internal(sk, NR_CONNREQ); } break; case NR_STATE_2: if (nr->n2count == nr->n2) { nr_disconnect(sk, ETIMEDOUT); goto out; } else { nr->n2count++; nr_write_internal(sk, NR_DISCREQ); } break; case NR_STATE_3: if (nr->n2count == nr->n2) { nr_disconnect(sk, ETIMEDOUT); goto out; } else { nr->n2count++; nr_requeue_frames(sk); } break; } nr_start_t1timer(sk); out: bh_unlock_sock(sk); sock_put(sk); }