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.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 init_timer(&nr->t1timer); 44 nr->t1timer.data = (unsigned long)sk; 45 nr->t1timer.function = &nr_t1timer_expiry; 46 47 init_timer(&nr->t2timer); 48 nr->t2timer.data = (unsigned long)sk; 49 nr->t2timer.function = &nr_t2timer_expiry; 50 51 init_timer(&nr->t4timer); 52 nr->t4timer.data = (unsigned long)sk; 53 nr->t4timer.function = &nr_t4timer_expiry; 54 55 init_timer(&nr->idletimer); 56 nr->idletimer.data = (unsigned long)sk; 57 nr->idletimer.function = &nr_idletimer_expiry; 58 59 /* initialized by sock_init_data */ 60 sk->sk_timer.data = (unsigned long)sk; 61 sk->sk_timer.function = &nr_heartbeat_expiry; 62 } 63 64 void nr_start_t1timer(struct sock *sk) 65 { 66 struct nr_sock *nr = nr_sk(sk); 67 68 mod_timer(&nr->t1timer, jiffies + nr->t1); 69 } 70 71 void nr_start_t2timer(struct sock *sk) 72 { 73 struct nr_sock *nr = nr_sk(sk); 74 75 mod_timer(&nr->t2timer, jiffies + nr->t2); 76 } 77 78 void nr_start_t4timer(struct sock *sk) 79 { 80 struct nr_sock *nr = nr_sk(sk); 81 82 mod_timer(&nr->t4timer, jiffies + nr->t4); 83 } 84 85 void nr_start_idletimer(struct sock *sk) 86 { 87 struct nr_sock *nr = nr_sk(sk); 88 89 if (nr->idle > 0) 90 mod_timer(&nr->idletimer, jiffies + nr->idle); 91 } 92 93 void nr_start_heartbeat(struct sock *sk) 94 { 95 mod_timer(&sk->sk_timer, jiffies + 5 * HZ); 96 } 97 98 void nr_stop_t1timer(struct sock *sk) 99 { 100 del_timer(&nr_sk(sk)->t1timer); 101 } 102 103 void nr_stop_t2timer(struct sock *sk) 104 { 105 del_timer(&nr_sk(sk)->t2timer); 106 } 107 108 void nr_stop_t4timer(struct sock *sk) 109 { 110 del_timer(&nr_sk(sk)->t4timer); 111 } 112 113 void nr_stop_idletimer(struct sock *sk) 114 { 115 del_timer(&nr_sk(sk)->idletimer); 116 } 117 118 void nr_stop_heartbeat(struct sock *sk) 119 { 120 del_timer(&sk->sk_timer); 121 } 122 123 int nr_t1timer_running(struct sock *sk) 124 { 125 return timer_pending(&nr_sk(sk)->t1timer); 126 } 127 128 static void nr_heartbeat_expiry(unsigned long param) 129 { 130 struct sock *sk = (struct sock *)param; 131 struct nr_sock *nr = nr_sk(sk); 132 133 bh_lock_sock(sk); 134 switch (nr->state) { 135 case NR_STATE_0: 136 /* Magic here: If we listen() and a new link dies before it 137 is accepted() it isn't 'dead' so doesn't get removed. */ 138 if (sock_flag(sk, SOCK_DESTROY) || 139 (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) { 140 sock_hold(sk); 141 nr_destroy_socket(sk); 142 bh_unlock_sock(sk); 143 sock_put(sk); 144 return; 145 } 146 break; 147 148 case NR_STATE_3: 149 /* 150 * Check for the state of the receive buffer. 151 */ 152 if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) && 153 (nr->condition & NR_COND_OWN_RX_BUSY)) { 154 nr->condition &= ~NR_COND_OWN_RX_BUSY; 155 nr->condition &= ~NR_COND_ACK_PENDING; 156 nr->vl = nr->vr; 157 nr_write_internal(sk, NR_INFOACK); 158 break; 159 } 160 break; 161 } 162 163 nr_start_heartbeat(sk); 164 bh_unlock_sock(sk); 165 } 166 167 static void nr_t2timer_expiry(unsigned long param) 168 { 169 struct sock *sk = (struct sock *)param; 170 struct nr_sock *nr = nr_sk(sk); 171 172 bh_lock_sock(sk); 173 if (nr->condition & NR_COND_ACK_PENDING) { 174 nr->condition &= ~NR_COND_ACK_PENDING; 175 nr_enquiry_response(sk); 176 } 177 bh_unlock_sock(sk); 178 } 179 180 static void nr_t4timer_expiry(unsigned long param) 181 { 182 struct sock *sk = (struct sock *)param; 183 184 bh_lock_sock(sk); 185 nr_sk(sk)->condition &= ~NR_COND_PEER_RX_BUSY; 186 bh_unlock_sock(sk); 187 } 188 189 static void nr_idletimer_expiry(unsigned long param) 190 { 191 struct sock *sk = (struct sock *)param; 192 struct nr_sock *nr = nr_sk(sk); 193 194 bh_lock_sock(sk); 195 196 nr_clear_queues(sk); 197 198 nr->n2count = 0; 199 nr_write_internal(sk, NR_DISCREQ); 200 nr->state = NR_STATE_2; 201 202 nr_start_t1timer(sk); 203 nr_stop_t2timer(sk); 204 nr_stop_t4timer(sk); 205 206 sk->sk_state = TCP_CLOSE; 207 sk->sk_err = 0; 208 sk->sk_shutdown |= SEND_SHUTDOWN; 209 210 if (!sock_flag(sk, SOCK_DEAD)) { 211 sk->sk_state_change(sk); 212 sock_set_flag(sk, SOCK_DEAD); 213 } 214 bh_unlock_sock(sk); 215 } 216 217 static void nr_t1timer_expiry(unsigned long param) 218 { 219 struct sock *sk = (struct sock *)param; 220 struct nr_sock *nr = nr_sk(sk); 221 222 bh_lock_sock(sk); 223 switch (nr->state) { 224 case NR_STATE_1: 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_CONNREQ); 232 } 233 break; 234 235 case NR_STATE_2: 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_write_internal(sk, NR_DISCREQ); 243 } 244 break; 245 246 case NR_STATE_3: 247 if (nr->n2count == nr->n2) { 248 nr_disconnect(sk, ETIMEDOUT); 249 bh_unlock_sock(sk); 250 return; 251 } else { 252 nr->n2count++; 253 nr_requeue_frames(sk); 254 } 255 break; 256 } 257 258 nr_start_t1timer(sk); 259 bh_unlock_sock(sk); 260 } 261