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 <linux/fcntl.h>
28#include <linux/mm.h>
29#include <linux/interrupt.h>
30#include <linux/init.h>
31
32ax25_dev *ax25_dev_list;
33DEFINE_SPINLOCK(ax25_dev_lock);
34
35ax25_dev *ax25_addr_ax25dev(ax25_address *addr)
36{
37	ax25_dev *ax25_dev, *res = NULL;
38
39	spin_lock_bh(&ax25_dev_lock);
40	for (ax25_dev = ax25_dev_list; ax25_dev != NULL; ax25_dev = ax25_dev->next)
41		if (ax25cmp(addr, (ax25_address *)ax25_dev->dev->dev_addr) == 0) {
42			res = ax25_dev;
43		}
44	spin_unlock_bh(&ax25_dev_lock);
45
46	return res;
47}
48
49/*
50 *	This is called when an interface is brought up. These are
51 *	reasonable defaults.
52 */
53void ax25_dev_device_up(struct net_device *dev)
54{
55	ax25_dev *ax25_dev;
56
57	if ((ax25_dev = kzalloc(sizeof(*ax25_dev), GFP_ATOMIC)) == NULL) {
58		printk(KERN_ERR "AX.25: ax25_dev_device_up - out of memory\n");
59		return;
60	}
61
62	dev->ax25_ptr     = ax25_dev;
63	ax25_dev->dev     = dev;
64	dev_hold(dev);
65	ax25_dev->forward = NULL;
66
67	ax25_dev->values[AX25_VALUES_IPDEFMODE] = AX25_DEF_IPDEFMODE;
68	ax25_dev->values[AX25_VALUES_AXDEFMODE] = AX25_DEF_AXDEFMODE;
69	ax25_dev->values[AX25_VALUES_BACKOFF]   = AX25_DEF_BACKOFF;
70	ax25_dev->values[AX25_VALUES_CONMODE]   = AX25_DEF_CONMODE;
71	ax25_dev->values[AX25_VALUES_WINDOW]    = AX25_DEF_WINDOW;
72	ax25_dev->values[AX25_VALUES_EWINDOW]   = AX25_DEF_EWINDOW;
73	ax25_dev->values[AX25_VALUES_T1]        = AX25_DEF_T1;
74	ax25_dev->values[AX25_VALUES_T2]        = AX25_DEF_T2;
75	ax25_dev->values[AX25_VALUES_T3]        = AX25_DEF_T3;
76	ax25_dev->values[AX25_VALUES_IDLE]	= AX25_DEF_IDLE;
77	ax25_dev->values[AX25_VALUES_N2]        = AX25_DEF_N2;
78	ax25_dev->values[AX25_VALUES_PACLEN]	= AX25_DEF_PACLEN;
79	ax25_dev->values[AX25_VALUES_PROTOCOL]  = AX25_DEF_PROTOCOL;
80	ax25_dev->values[AX25_VALUES_DS_TIMEOUT]= AX25_DEF_DS_TIMEOUT;
81
82#if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER)
83	ax25_ds_setup_timer(ax25_dev);
84#endif
85
86	spin_lock_bh(&ax25_dev_lock);
87	ax25_dev->next = ax25_dev_list;
88	ax25_dev_list  = ax25_dev;
89	spin_unlock_bh(&ax25_dev_lock);
90
91	ax25_register_dev_sysctl(ax25_dev);
92}
93
94void ax25_dev_device_down(struct net_device *dev)
95{
96	ax25_dev *s, *ax25_dev;
97
98	if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
99		return;
100
101	ax25_unregister_dev_sysctl(ax25_dev);
102
103	spin_lock_bh(&ax25_dev_lock);
104
105#ifdef CONFIG_AX25_DAMA_SLAVE
106	ax25_ds_del_timer(ax25_dev);
107#endif
108
109	/*
110	 *	Remove any packet forwarding that points to this device.
111	 */
112	for (s = ax25_dev_list; s != NULL; s = s->next)
113		if (s->forward == dev)
114			s->forward = NULL;
115
116	if ((s = ax25_dev_list) == ax25_dev) {
117		ax25_dev_list = s->next;
118		spin_unlock_bh(&ax25_dev_lock);
119		dev_put(dev);
120		kfree(ax25_dev);
121		return;
122	}
123
124	while (s != NULL && s->next != NULL) {
125		if (s->next == ax25_dev) {
126			s->next = ax25_dev->next;
127			spin_unlock_bh(&ax25_dev_lock);
128			dev_put(dev);
129			kfree(ax25_dev);
130			return;
131		}
132
133		s = s->next;
134	}
135	spin_unlock_bh(&ax25_dev_lock);
136	dev->ax25_ptr = NULL;
137}
138
139int ax25_fwd_ioctl(unsigned int cmd, struct ax25_fwd_struct *fwd)
140{
141	ax25_dev *ax25_dev, *fwd_dev;
142
143	if ((ax25_dev = ax25_addr_ax25dev(&fwd->port_from)) == NULL)
144		return -EINVAL;
145
146	switch (cmd) {
147	case SIOCAX25ADDFWD:
148		if ((fwd_dev = ax25_addr_ax25dev(&fwd->port_to)) == NULL)
149			return -EINVAL;
150		if (ax25_dev->forward != NULL)
151			return -EINVAL;
152		ax25_dev->forward = fwd_dev->dev;
153		break;
154
155	case SIOCAX25DELFWD:
156		if (ax25_dev->forward == NULL)
157			return -EINVAL;
158		ax25_dev->forward = NULL;
159		break;
160
161	default:
162		return -EINVAL;
163	}
164
165	return 0;
166}
167
168struct net_device *ax25_fwd_dev(struct net_device *dev)
169{
170	ax25_dev *ax25_dev;
171
172	if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
173		return dev;
174
175	if (ax25_dev->forward == NULL)
176		return dev;
177
178	return ax25_dev->forward;
179}
180
181/*
182 *	Free all memory associated with device structures.
183 */
184void __exit ax25_dev_free(void)
185{
186	ax25_dev *s, *ax25_dev;
187
188	spin_lock_bh(&ax25_dev_lock);
189	ax25_dev = ax25_dev_list;
190	while (ax25_dev != NULL) {
191		s        = ax25_dev;
192		dev_put(ax25_dev->dev);
193		ax25_dev = ax25_dev->next;
194		kfree(s);
195	}
196	ax25_dev_list = NULL;
197	spin_unlock_bh(&ax25_dev_lock);
198}
199