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 */
9 #include <linux/errno.h>
10 #include <linux/types.h>
11 #include <linux/socket.h>
12 #include <linux/in.h>
13 #include <linux/kernel.h>
14 #include <linux/timer.h>
15 #include <linux/string.h>
16 #include <linux/sockios.h>
17 #include <linux/net.h>
18 #include <net/ax25.h>
19 #include <linux/inet.h>
20 #include <linux/netdevice.h>
21 #include <linux/skbuff.h>
22 #include <net/sock.h>
23 #include <asm/uaccess.h>
24 #include <linux/fcntl.h>
25 #include <linux/mm.h>
26 #include <linux/interrupt.h>
27
28 /*
29 * The following routines are taken from page 170 of the 7th ARRL Computer
30 * Networking Conference paper, as is the whole state machine.
31 */
32
ax25_std_nr_error_recovery(ax25_cb * ax25)33 void ax25_std_nr_error_recovery(ax25_cb *ax25)
34 {
35 ax25_std_establish_data_link(ax25);
36 }
37
ax25_std_establish_data_link(ax25_cb * ax25)38 void ax25_std_establish_data_link(ax25_cb *ax25)
39 {
40 ax25->condition = 0x00;
41 ax25->n2count = 0;
42
43 if (ax25->modulus == AX25_MODULUS)
44 ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND);
45 else
46 ax25_send_control(ax25, AX25_SABME, AX25_POLLON, AX25_COMMAND);
47
48 ax25_calculate_t1(ax25);
49 ax25_stop_idletimer(ax25);
50 ax25_stop_t3timer(ax25);
51 ax25_stop_t2timer(ax25);
52 ax25_start_t1timer(ax25);
53 }
54
ax25_std_transmit_enquiry(ax25_cb * ax25)55 void ax25_std_transmit_enquiry(ax25_cb *ax25)
56 {
57 if (ax25->condition & AX25_COND_OWN_RX_BUSY)
58 ax25_send_control(ax25, AX25_RNR, AX25_POLLON, AX25_COMMAND);
59 else
60 ax25_send_control(ax25, AX25_RR, AX25_POLLON, AX25_COMMAND);
61
62 ax25->condition &= ~AX25_COND_ACK_PENDING;
63
64 ax25_calculate_t1(ax25);
65 ax25_start_t1timer(ax25);
66 }
67
ax25_std_enquiry_response(ax25_cb * ax25)68 void ax25_std_enquiry_response(ax25_cb *ax25)
69 {
70 if (ax25->condition & AX25_COND_OWN_RX_BUSY)
71 ax25_send_control(ax25, AX25_RNR, AX25_POLLON, AX25_RESPONSE);
72 else
73 ax25_send_control(ax25, AX25_RR, AX25_POLLON, AX25_RESPONSE);
74
75 ax25->condition &= ~AX25_COND_ACK_PENDING;
76 }
77
ax25_std_timeout_response(ax25_cb * ax25)78 void ax25_std_timeout_response(ax25_cb *ax25)
79 {
80 if (ax25->condition & AX25_COND_OWN_RX_BUSY)
81 ax25_send_control(ax25, AX25_RNR, AX25_POLLOFF, AX25_RESPONSE);
82 else
83 ax25_send_control(ax25, AX25_RR, AX25_POLLOFF, AX25_RESPONSE);
84
85 ax25->condition &= ~AX25_COND_ACK_PENDING;
86 }
87