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/slab.h>
13#include <linux/in.h>
14#include <linux/kernel.h>
15#include <linux/timer.h>
16#include <linux/string.h>
17#include <linux/sockios.h>
18#include <linux/net.h>
19#include <linux/spinlock.h>
20#include <net/ax25.h>
21#include <linux/inet.h>
22#include <linux/netdevice.h>
23#include <linux/if_arp.h>
24#include <linux/skbuff.h>
25#include <net/sock.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 <linux/init.h>
32
33ax25_dev *ax25_dev_list;
34DEFINE_SPINLOCK(ax25_dev_lock);
35
36ax25_dev *ax25_addr_ax25dev(ax25_address *addr)
37{
38	ax25_dev *ax25_dev, *res = NULL;
39
40	spin_lock_bh(&ax25_dev_lock);
41	for (ax25_dev = ax25_dev_list; ax25_dev != NULL; ax25_dev = ax25_dev->next)
42		if (ax25cmp(addr, (ax25_address *)ax25_dev->dev->dev_addr) == 0) {
43			res = ax25_dev;
44		}
45	spin_unlock_bh(&ax25_dev_lock);
46
47	return res;
48}
49
50/*
51 *	This is called when an interface is brought up. These are
52 *	reasonable defaults.
53 */
54void ax25_dev_device_up(struct net_device *dev)
55{
56	ax25_dev *ax25_dev;
57
58	if ((ax25_dev = kzalloc(sizeof(*ax25_dev), GFP_ATOMIC)) == NULL) {
59		printk(KERN_ERR "AX.25: ax25_dev_device_up - out of memory\n");
60		return;
61	}
62
63	ax25_unregister_sysctl();
64
65	dev->ax25_ptr     = ax25_dev;
66	ax25_dev->dev     = dev;
67	dev_hold(dev);
68	ax25_dev->forward = NULL;
69
70	ax25_dev->values[AX25_VALUES_IPDEFMODE] = AX25_DEF_IPDEFMODE;
71	ax25_dev->values[AX25_VALUES_AXDEFMODE] = AX25_DEF_AXDEFMODE;
72	ax25_dev->values[AX25_VALUES_BACKOFF]   = AX25_DEF_BACKOFF;
73	ax25_dev->values[AX25_VALUES_CONMODE]   = AX25_DEF_CONMODE;
74	ax25_dev->values[AX25_VALUES_WINDOW]    = AX25_DEF_WINDOW;
75	ax25_dev->values[AX25_VALUES_EWINDOW]   = AX25_DEF_EWINDOW;
76	ax25_dev->values[AX25_VALUES_T1]        = AX25_DEF_T1;
77	ax25_dev->values[AX25_VALUES_T2]        = AX25_DEF_T2;
78	ax25_dev->values[AX25_VALUES_T3]        = AX25_DEF_T3;
79	ax25_dev->values[AX25_VALUES_IDLE]	= AX25_DEF_IDLE;
80	ax25_dev->values[AX25_VALUES_N2]        = AX25_DEF_N2;
81	ax25_dev->values[AX25_VALUES_PACLEN]	= AX25_DEF_PACLEN;
82	ax25_dev->values[AX25_VALUES_PROTOCOL]  = AX25_DEF_PROTOCOL;
83	ax25_dev->values[AX25_VALUES_DS_TIMEOUT]= AX25_DEF_DS_TIMEOUT;
84
85#if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER)
86	ax25_ds_setup_timer(ax25_dev);
87#endif
88
89	spin_lock_bh(&ax25_dev_lock);
90	ax25_dev->next = ax25_dev_list;
91	ax25_dev_list  = ax25_dev;
92	spin_unlock_bh(&ax25_dev_lock);
93
94	ax25_register_sysctl();
95}
96
97void ax25_dev_device_down(struct net_device *dev)
98{
99	ax25_dev *s, *ax25_dev;
100
101	if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
102		return;
103
104	ax25_unregister_sysctl();
105
106	spin_lock_bh(&ax25_dev_lock);
107
108#ifdef CONFIG_AX25_DAMA_SLAVE
109	ax25_ds_del_timer(ax25_dev);
110#endif
111
112	/*
113	 *	Remove any packet forwarding that points to this device.
114	 */
115	for (s = ax25_dev_list; s != NULL; s = s->next)
116		if (s->forward == dev)
117			s->forward = NULL;
118
119	if ((s = ax25_dev_list) == ax25_dev) {
120		ax25_dev_list = s->next;
121		spin_unlock_bh(&ax25_dev_lock);
122		dev_put(dev);
123		kfree(ax25_dev);
124		ax25_register_sysctl();
125		return;
126	}
127
128	while (s != NULL && s->next != NULL) {
129		if (s->next == ax25_dev) {
130			s->next = ax25_dev->next;
131			spin_unlock_bh(&ax25_dev_lock);
132			dev_put(dev);
133			kfree(ax25_dev);
134			ax25_register_sysctl();
135			return;
136		}
137
138		s = s->next;
139	}
140	spin_unlock_bh(&ax25_dev_lock);
141	dev->ax25_ptr = NULL;
142
143	ax25_register_sysctl();
144}
145
146int ax25_fwd_ioctl(unsigned int cmd, struct ax25_fwd_struct *fwd)
147{
148	ax25_dev *ax25_dev, *fwd_dev;
149
150	if ((ax25_dev = ax25_addr_ax25dev(&fwd->port_from)) == NULL)
151		return -EINVAL;
152
153	switch (cmd) {
154	case SIOCAX25ADDFWD:
155		if ((fwd_dev = ax25_addr_ax25dev(&fwd->port_to)) == NULL)
156			return -EINVAL;
157		if (ax25_dev->forward != NULL)
158			return -EINVAL;
159		ax25_dev->forward = fwd_dev->dev;
160		break;
161
162	case SIOCAX25DELFWD:
163		if (ax25_dev->forward == NULL)
164			return -EINVAL;
165		ax25_dev->forward = NULL;
166		break;
167
168	default:
169		return -EINVAL;
170	}
171
172	return 0;
173}
174
175struct net_device *ax25_fwd_dev(struct net_device *dev)
176{
177	ax25_dev *ax25_dev;
178
179	if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
180		return dev;
181
182	if (ax25_dev->forward == NULL)
183		return dev;
184
185	return ax25_dev->forward;
186}
187
188/*
189 *	Free all memory associated with device structures.
190 */
191void __exit ax25_dev_free(void)
192{
193	ax25_dev *s, *ax25_dev;
194
195	spin_lock_bh(&ax25_dev_lock);
196	ax25_dev = ax25_dev_list;
197	while (ax25_dev != NULL) {
198		s        = ax25_dev;
199		dev_put(ax25_dev->dev);
200		ax25_dev = ax25_dev->next;
201		kfree(s);
202	}
203	ax25_dev_list = NULL;
204	spin_unlock_bh(&ax25_dev_lock);
205}
206