1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * |
4 | * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) |
5 | */ |
6 | #include <linux/errno.h> |
7 | #include <linux/types.h> |
8 | #include <linux/socket.h> |
9 | #include <linux/in.h> |
10 | #include <linux/kernel.h> |
11 | #include <linux/timer.h> |
12 | #include <linux/string.h> |
13 | #include <linux/sockios.h> |
14 | #include <linux/net.h> |
15 | #include <net/ax25.h> |
16 | #include <linux/inet.h> |
17 | #include <linux/netdevice.h> |
18 | #include <linux/skbuff.h> |
19 | #include <net/sock.h> |
20 | #include <linux/uaccess.h> |
21 | #include <linux/fcntl.h> |
22 | #include <linux/mm.h> |
23 | #include <linux/interrupt.h> |
24 | |
25 | /* |
26 | * The following routines are taken from page 170 of the 7th ARRL Computer |
27 | * Networking Conference paper, as is the whole state machine. |
28 | */ |
29 | |
30 | void ax25_std_nr_error_recovery(ax25_cb *ax25) |
31 | { |
32 | ax25_std_establish_data_link(ax25); |
33 | } |
34 | |
35 | void ax25_std_establish_data_link(ax25_cb *ax25) |
36 | { |
37 | ax25->condition = 0x00; |
38 | ax25->n2count = 0; |
39 | |
40 | if (ax25->modulus == AX25_MODULUS) |
41 | ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND); |
42 | else |
43 | ax25_send_control(ax25, AX25_SABME, AX25_POLLON, AX25_COMMAND); |
44 | |
45 | ax25_calculate_t1(ax25); |
46 | ax25_stop_idletimer(ax25); |
47 | ax25_stop_t3timer(ax25); |
48 | ax25_stop_t2timer(ax25); |
49 | ax25_start_t1timer(ax25); |
50 | } |
51 | |
52 | void ax25_std_transmit_enquiry(ax25_cb *ax25) |
53 | { |
54 | if (ax25->condition & AX25_COND_OWN_RX_BUSY) |
55 | ax25_send_control(ax25, AX25_RNR, AX25_POLLON, AX25_COMMAND); |
56 | else |
57 | ax25_send_control(ax25, AX25_RR, AX25_POLLON, AX25_COMMAND); |
58 | |
59 | ax25->condition &= ~AX25_COND_ACK_PENDING; |
60 | |
61 | ax25_calculate_t1(ax25); |
62 | ax25_start_t1timer(ax25); |
63 | } |
64 | |
65 | void ax25_std_enquiry_response(ax25_cb *ax25) |
66 | { |
67 | if (ax25->condition & AX25_COND_OWN_RX_BUSY) |
68 | ax25_send_control(ax25, AX25_RNR, AX25_POLLON, AX25_RESPONSE); |
69 | else |
70 | ax25_send_control(ax25, AX25_RR, AX25_POLLON, AX25_RESPONSE); |
71 | |
72 | ax25->condition &= ~AX25_COND_ACK_PENDING; |
73 | } |
74 | |
75 | void ax25_std_timeout_response(ax25_cb *ax25) |
76 | { |
77 | if (ax25->condition & AX25_COND_OWN_RX_BUSY) |
78 | ax25_send_control(ax25, AX25_RNR, AX25_POLLOFF, AX25_RESPONSE); |
79 | else |
80 | ax25_send_control(ax25, AX25_RR, AX25_POLLOFF, AX25_RESPONSE); |
81 | |
82 | ax25->condition &= ~AX25_COND_ACK_PENDING; |
83 | } |
84 | |