1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * |
4 | * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) |
5 | * Copyright (C) 2002 Ralf Baechle DO1GRB (ralf@gnu.org) |
6 | */ |
7 | #include <linux/errno.h> |
8 | #include <linux/types.h> |
9 | #include <linux/socket.h> |
10 | #include <linux/in.h> |
11 | #include <linux/kernel.h> |
12 | #include <linux/jiffies.h> |
13 | #include <linux/timer.h> |
14 | #include <linux/string.h> |
15 | #include <linux/sockios.h> |
16 | #include <linux/net.h> |
17 | #include <net/ax25.h> |
18 | #include <linux/inet.h> |
19 | #include <linux/netdevice.h> |
20 | #include <linux/skbuff.h> |
21 | #include <net/sock.h> |
22 | #include <net/tcp_states.h> |
23 | #include <linux/fcntl.h> |
24 | #include <linux/mm.h> |
25 | #include <linux/interrupt.h> |
26 | #include <net/rose.h> |
27 | |
28 | static void rose_heartbeat_expiry(struct timer_list *t); |
29 | static void rose_timer_expiry(struct timer_list *); |
30 | static void rose_idletimer_expiry(struct timer_list *); |
31 | |
32 | void rose_start_heartbeat(struct sock *sk) |
33 | { |
34 | sk_stop_timer(sk, timer: &sk->sk_timer); |
35 | |
36 | sk->sk_timer.function = rose_heartbeat_expiry; |
37 | sk->sk_timer.expires = jiffies + 5 * HZ; |
38 | |
39 | sk_reset_timer(sk, timer: &sk->sk_timer, expires: sk->sk_timer.expires); |
40 | } |
41 | |
42 | void rose_start_t1timer(struct sock *sk) |
43 | { |
44 | struct rose_sock *rose = rose_sk(sk); |
45 | |
46 | sk_stop_timer(sk, timer: &rose->timer); |
47 | |
48 | rose->timer.function = rose_timer_expiry; |
49 | rose->timer.expires = jiffies + rose->t1; |
50 | |
51 | sk_reset_timer(sk, timer: &rose->timer, expires: rose->timer.expires); |
52 | } |
53 | |
54 | void rose_start_t2timer(struct sock *sk) |
55 | { |
56 | struct rose_sock *rose = rose_sk(sk); |
57 | |
58 | sk_stop_timer(sk, timer: &rose->timer); |
59 | |
60 | rose->timer.function = rose_timer_expiry; |
61 | rose->timer.expires = jiffies + rose->t2; |
62 | |
63 | sk_reset_timer(sk, timer: &rose->timer, expires: rose->timer.expires); |
64 | } |
65 | |
66 | void rose_start_t3timer(struct sock *sk) |
67 | { |
68 | struct rose_sock *rose = rose_sk(sk); |
69 | |
70 | sk_stop_timer(sk, timer: &rose->timer); |
71 | |
72 | rose->timer.function = rose_timer_expiry; |
73 | rose->timer.expires = jiffies + rose->t3; |
74 | |
75 | sk_reset_timer(sk, timer: &rose->timer, expires: rose->timer.expires); |
76 | } |
77 | |
78 | void rose_start_hbtimer(struct sock *sk) |
79 | { |
80 | struct rose_sock *rose = rose_sk(sk); |
81 | |
82 | sk_stop_timer(sk, timer: &rose->timer); |
83 | |
84 | rose->timer.function = rose_timer_expiry; |
85 | rose->timer.expires = jiffies + rose->hb; |
86 | |
87 | sk_reset_timer(sk, timer: &rose->timer, expires: rose->timer.expires); |
88 | } |
89 | |
90 | void rose_start_idletimer(struct sock *sk) |
91 | { |
92 | struct rose_sock *rose = rose_sk(sk); |
93 | |
94 | sk_stop_timer(sk, timer: &rose->idletimer); |
95 | |
96 | if (rose->idle > 0) { |
97 | rose->idletimer.function = rose_idletimer_expiry; |
98 | rose->idletimer.expires = jiffies + rose->idle; |
99 | |
100 | sk_reset_timer(sk, timer: &rose->idletimer, expires: rose->idletimer.expires); |
101 | } |
102 | } |
103 | |
104 | void rose_stop_heartbeat(struct sock *sk) |
105 | { |
106 | sk_stop_timer(sk, timer: &sk->sk_timer); |
107 | } |
108 | |
109 | void rose_stop_timer(struct sock *sk) |
110 | { |
111 | sk_stop_timer(sk, timer: &rose_sk(sk)->timer); |
112 | } |
113 | |
114 | void rose_stop_idletimer(struct sock *sk) |
115 | { |
116 | sk_stop_timer(sk, timer: &rose_sk(sk)->idletimer); |
117 | } |
118 | |
119 | static void rose_heartbeat_expiry(struct timer_list *t) |
120 | { |
121 | struct sock *sk = from_timer(sk, t, sk_timer); |
122 | struct rose_sock *rose = rose_sk(sk); |
123 | |
124 | bh_lock_sock(sk); |
125 | switch (rose->state) { |
126 | case ROSE_STATE_0: |
127 | /* Magic here: If we listen() and a new link dies before it |
128 | is accepted() it isn't 'dead' so doesn't get removed. */ |
129 | if (sock_flag(sk, flag: SOCK_DESTROY) || |
130 | (sk->sk_state == TCP_LISTEN && sock_flag(sk, flag: SOCK_DEAD))) { |
131 | bh_unlock_sock(sk); |
132 | rose_destroy_socket(sk); |
133 | sock_put(sk); |
134 | return; |
135 | } |
136 | break; |
137 | |
138 | case ROSE_STATE_3: |
139 | /* |
140 | * Check for the state of the receive buffer. |
141 | */ |
142 | if (atomic_read(v: &sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) && |
143 | (rose->condition & ROSE_COND_OWN_RX_BUSY)) { |
144 | rose->condition &= ~ROSE_COND_OWN_RX_BUSY; |
145 | rose->condition &= ~ROSE_COND_ACK_PENDING; |
146 | rose->vl = rose->vr; |
147 | rose_write_internal(sk, ROSE_RR); |
148 | rose_stop_timer(sk); /* HB */ |
149 | break; |
150 | } |
151 | break; |
152 | } |
153 | |
154 | rose_start_heartbeat(sk); |
155 | bh_unlock_sock(sk); |
156 | sock_put(sk); |
157 | } |
158 | |
159 | static void rose_timer_expiry(struct timer_list *t) |
160 | { |
161 | struct rose_sock *rose = from_timer(rose, t, timer); |
162 | struct sock *sk = &rose->sock; |
163 | |
164 | bh_lock_sock(sk); |
165 | switch (rose->state) { |
166 | case ROSE_STATE_1: /* T1 */ |
167 | case ROSE_STATE_4: /* T2 */ |
168 | rose_write_internal(sk, ROSE_CLEAR_REQUEST); |
169 | rose->state = ROSE_STATE_2; |
170 | rose_start_t3timer(sk); |
171 | break; |
172 | |
173 | case ROSE_STATE_2: /* T3 */ |
174 | rose->neighbour->use--; |
175 | rose_disconnect(sk, ETIMEDOUT, -1, -1); |
176 | break; |
177 | |
178 | case ROSE_STATE_3: /* HB */ |
179 | if (rose->condition & ROSE_COND_ACK_PENDING) { |
180 | rose->condition &= ~ROSE_COND_ACK_PENDING; |
181 | rose_enquiry_response(sk); |
182 | } |
183 | break; |
184 | } |
185 | bh_unlock_sock(sk); |
186 | sock_put(sk); |
187 | } |
188 | |
189 | static void rose_idletimer_expiry(struct timer_list *t) |
190 | { |
191 | struct rose_sock *rose = from_timer(rose, t, idletimer); |
192 | struct sock *sk = &rose->sock; |
193 | |
194 | bh_lock_sock(sk); |
195 | rose_clear_queues(sk); |
196 | |
197 | rose_write_internal(sk, ROSE_CLEAR_REQUEST); |
198 | rose_sk(sk)->state = ROSE_STATE_2; |
199 | |
200 | rose_start_t3timer(sk); |
201 | |
202 | sk->sk_state = TCP_CLOSE; |
203 | sk->sk_err = 0; |
204 | sk->sk_shutdown |= SEND_SHUTDOWN; |
205 | |
206 | if (!sock_flag(sk, flag: SOCK_DEAD)) { |
207 | sk->sk_state_change(sk); |
208 | sock_set_flag(sk, flag: SOCK_DEAD); |
209 | } |
210 | bh_unlock_sock(sk); |
211 | sock_put(sk); |
212 | } |
213 | |