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) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) 8 * Copyright (C) 2002 Ralf Baechle DO1GRB (ralf@gnu.org) 9 */ 10 #include <linux/errno.h> 11 #include <linux/types.h> 12 #include <linux/socket.h> 13 #include <linux/in.h> 14 #include <linux/kernel.h> 15 #include <linux/jiffies.h> 16 #include <linux/timer.h> 17 #include <linux/string.h> 18 #include <linux/sockios.h> 19 #include <linux/net.h> 20 #include <net/ax25.h> 21 #include <linux/inet.h> 22 #include <linux/netdevice.h> 23 #include <linux/skbuff.h> 24 #include <net/sock.h> 25 #include <net/tcp_states.h> 26 #include <asm/uaccess.h> 27 #include <asm/system.h> 28 #include <linux/fcntl.h> 29 #include <linux/mm.h> 30 #include <linux/interrupt.h> 31 #include <net/netrom.h> 32 33 static void nr_heartbeat_expiry(unsigned long); 34 static void nr_t1timer_expiry(unsigned long); 35 static void nr_t2timer_expiry(unsigned long); 36 static void nr_t4timer_expiry(unsigned long); 37 static void nr_idletimer_expiry(unsigned long); 38 39 void nr_init_timers(struct sock *sk) 40 { 41 struct nr_sock *nr = nr_sk(sk); 42 43 setup_timer(&nr->t1timer, nr_t1timer_expiry, (unsigned long)sk); 44 setup_timer(&nr->t2timer, nr_t2timer_expiry, (unsigned long)sk); 45 setup_timer(&nr->t4timer, nr_t4timer_expiry, (unsigned long)sk); 46 setup_timer(&nr->idletimer, nr_idletimer_expiry, (unsigned long)sk); 47 48 /* initialized by sock_init_data */ 49 sk->sk_timer.data = (unsigned long)sk; 50 sk->sk_timer.function = &nr_heartbeat_expiry; 51 } 52 53 void nr_start_t1timer(struct sock *sk) 54 { 55 struct nr_sock *nr = nr_sk(sk); 56 57 mod_timer(&nr->t1timer, jiffies + nr->t1); 58 } 59 60 void nr_start_t2timer(struct sock *sk) 61 { 62 struct nr_sock *nr = nr_sk(sk); 63 64 mod_timer(&nr->t2timer, jiffies + nr->t2); 65 } 66 67 void nr_start_t4timer(struct sock *sk) 68 { 69 struct nr_sock *nr = nr_sk(sk); 70 71 mod_timer(&nr->t4timer, jiffies + nr->t4); 72 } 73 74 void nr_start_idletimer(struct sock *sk) 75 { 76 struct nr_sock *nr = nr_sk(sk); 77 78 if (nr->idle > 0) 79 mod_timer(&nr->idletimer, jiffies + nr->idle); 80 } 81 82 void nr_start_heartbeat(struct sock *sk) 83 { 84 mod_timer(&sk->sk_timer, jiffies + 5 * HZ); 85 } 86 87 void nr_stop_t1timer(struct sock *sk) 88 { 89 del_timer(&nr_sk(sk)->t1timer); 90 } 91 92 void nr_stop_t2timer(struct sock *sk) 93 { 94 del_timer(&nr_sk(sk)->t2timer); 95 } 96 97 void nr_stop_t4timer(struct sock *sk) 98 { 99 del_timer(&nr_sk(sk)->t4timer); 100 } 101 102 void nr_stop_idletimer(struct sock *sk) 103 { 104 del_timer(&nr_sk(sk)->idletimer); 105 } 106 107 void nr_stop_heartbeat(struct sock *sk) 108 { 109 del_timer(&sk->sk_timer); 110 } 111 112 int nr_t1timer_running(struct sock *sk) 113 { 114 return timer_pending(&nr_sk(sk)->t1timer); 115 } 116 117 static void nr_heartbeat_expiry(unsigned long param) 118 { 119 struct sock *sk = (struct sock *)param; 120 struct nr_sock *nr = nr_sk(sk); 121 122 bh_lock_sock(sk); 123 switch (nr->state) { 124 case NR_STATE_0: 125 /* Magic here: If we listen() and a new link dies before it 126 is accepted() it isn't 'dead' so doesn't get removed. */ 127 if (sock_flag(sk, SOCK_DESTROY) || 128 (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) { 129 sock_hold(sk); 130 bh_unlock_sock(sk); 131 nr_destroy_socket(sk); 132 sock_put(sk); 133 return; 134 } 135 break; 136 137 case NR_STATE_3: 138 /* 139 * Check for the state of the receive buffer. 140 */ 141 if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) && 142 (nr->condition & NR_COND_OWN_RX_BUSY)) { 143 nr->condition &= ~NR_COND_OWN_RX_BUSY; 144 nr->condition &= ~NR_COND_ACK_PENDING; 145 nr->vl = nr->vr; 146 nr_write_internal(sk, NR_INFOACK); 147 break; 148 } 149 break; 150 } 151 152 nr_start_heartbeat(sk); 153 bh_unlock_sock(sk); 154 } 155 156 static void nr_t2timer_expiry(unsigned long param) 157 { 158 struct sock *sk = (struct sock *)param; 159 struct nr_sock *nr = nr_sk(sk); 160 161 bh_lock_sock(sk); 162 if (nr->condition & NR_COND_ACK_PENDING) { 163 nr->condition &= ~NR_COND_ACK_PENDING; 164 nr_enquiry_response(sk); 165 } 166 bh_unlock_sock(sk); 167 } 168 169 static void nr_t4timer_expiry(unsigned long param) 170 { 171 struct sock *sk = (struct sock *)param; 172 173 bh_lock_sock(sk); 174 nr_sk(sk)->condition &= ~NR_COND_PEER_RX_BUSY; 175 bh_unlock_sock(sk); 176 } 177 178 static void nr_idletimer_expiry(unsigned long param) 179 { 180 struct sock *sk = (struct sock *)param; 181 struct nr_sock *nr = nr_sk(sk); 182 183 bh_lock_sock(sk); 184 185 nr_clear_queues(sk); 186 187 nr->n2count = 0; 188 nr_write_internal(sk, NR_DISCREQ); 189 nr->state = NR_STATE_2; 190 191 nr_start_t1timer(sk); 192 nr_stop_t2timer(sk); 193 nr_stop_t4timer(sk); 194 195 sk->sk_state = TCP_CLOSE; 196 sk->sk_err = 0; 197 sk->sk_shutdown |= SEND_SHUTDOWN; 198 199 if (!sock_flag(sk, SOCK_DEAD)) { 200 sk->sk_state_change(sk); 201 sock_set_flag(sk, SOCK_DEAD); 202 } 203 bh_unlock_sock(sk); 204 } 205 206 static void nr_t1timer_expiry(unsigned long param) 207 { 208 struct sock *sk = (struct sock *)param; 209 struct nr_sock *nr = nr_sk(sk); 210 211 bh_lock_sock(sk); 212 switch (nr->state) { 213 case NR_STATE_1: 214 if (nr->n2count == nr->n2) { 215 nr_disconnect(sk, ETIMEDOUT); 216 bh_unlock_sock(sk); 217 return; 218 } else { 219 nr->n2count++; 220 nr_write_internal(sk, NR_CONNREQ); 221 } 222 break; 223 224 case NR_STATE_2: 225 if (nr->n2count == nr->n2) { 226 nr_disconnect(sk, ETIMEDOUT); 227 bh_unlock_sock(sk); 228 return; 229 } else { 230 nr->n2count++; 231 nr_write_internal(sk, NR_DISCREQ); 232 } 233 break; 234 235 case NR_STATE_3: 236 if (nr->n2count == nr->n2) { 237 nr_disconnect(sk, ETIMEDOUT); 238 bh_unlock_sock(sk); 239 return; 240 } else { 241 nr->n2count++; 242 nr_requeue_frames(sk); 243 } 244 break; 245 } 246 247 nr_start_t1timer(sk); 248 bh_unlock_sock(sk); 249 } 250