[NETFILTER]: ip_conntrack: properly use RCU for ip_conntrack_destroyed callback
[linux-2.6] / net / ax25 / ax25_dev.c
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/sched.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
33 ax25_dev *ax25_dev_list;
34 DEFINE_SPINLOCK(ax25_dev_lock);
35
36 ax25_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  */
54 void 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         init_timer(&ax25_dev->dama.slave_timer);
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
97 void 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
146 int 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
175 struct 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  */
191 void __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 }