iucv: Fix bad merging.
[linux-2.6.git] / net / x25 / x25_route.c
1 /*
2  *      X.25 Packet Layer release 002
3  *
4  *      This is ALPHA test software. This code may break your machine,
5  *      randomly fail to work with new releases, misbehave and/or generally
6  *      screw up. It might even work.
7  *
8  *      This code REQUIRES 2.1.15 or higher
9  *
10  *      This module:
11  *              This module is free software; you can redistribute it and/or
12  *              modify it under the terms of the GNU General Public License
13  *              as published by the Free Software Foundation; either version
14  *              2 of the License, or (at your option) any later version.
15  *
16  *      History
17  *      X.25 001        Jonathan Naylor Started coding.
18  */
19
20 #include <linux/if_arp.h>
21 #include <linux/init.h>
22 #include <net/x25.h>
23
24 LIST_HEAD(x25_route_list);
25 DEFINE_RWLOCK(x25_route_list_lock);
26
27 /*
28  *      Add a new route.
29  */
30 static int x25_add_route(struct x25_address *address, unsigned int sigdigits,
31                          struct net_device *dev)
32 {
33         struct x25_route *rt;
34         struct list_head *entry;
35         int rc = -EINVAL;
36
37         write_lock_bh(&x25_route_list_lock);
38
39         list_for_each(entry, &x25_route_list) {
40                 rt = list_entry(entry, struct x25_route, node);
41
42                 if (!memcmp(&rt->address, address, sigdigits) &&
43                     rt->sigdigits == sigdigits)
44                         goto out;
45         }
46
47         rt = kmalloc(sizeof(*rt), GFP_ATOMIC);
48         rc = -ENOMEM;
49         if (!rt)
50                 goto out;
51
52         strcpy(rt->address.x25_addr, "000000000000000");
53         memcpy(rt->address.x25_addr, address->x25_addr, sigdigits);
54
55         rt->sigdigits = sigdigits;
56         rt->dev       = dev;
57         atomic_set(&rt->refcnt, 1);
58
59         list_add(&rt->node, &x25_route_list);
60         rc = 0;
61 out:
62         write_unlock_bh(&x25_route_list_lock);
63         return rc;
64 }
65
66 /**
67  * __x25_remove_route - remove route from x25_route_list
68  * @rt - route to remove
69  *
70  * Remove route from x25_route_list. If it was there.
71  * Caller must hold x25_route_list_lock.
72  */
73 static void __x25_remove_route(struct x25_route *rt)
74 {
75         if (rt->node.next) {
76                 list_del(&rt->node);
77                 x25_route_put(rt);
78         }
79 }
80
81 static int x25_del_route(struct x25_address *address, unsigned int sigdigits,
82                          struct net_device *dev)
83 {
84         struct x25_route *rt;
85         struct list_head *entry;
86         int rc = -EINVAL;
87
88         write_lock_bh(&x25_route_list_lock);
89
90         list_for_each(entry, &x25_route_list) {
91                 rt = list_entry(entry, struct x25_route, node);
92
93                 if (!memcmp(&rt->address, address, sigdigits) &&
94                     rt->sigdigits == sigdigits && rt->dev == dev) {
95                         __x25_remove_route(rt);
96                         rc = 0;
97                         break;
98                 }
99         }
100
101         write_unlock_bh(&x25_route_list_lock);
102         return rc;
103 }
104
105 /*
106  *      A device has been removed, remove its routes.
107  */
108 void x25_route_device_down(struct net_device *dev)
109 {
110         struct x25_route *rt;
111         struct list_head *entry, *tmp;
112
113         write_lock_bh(&x25_route_list_lock);
114
115         list_for_each_safe(entry, tmp, &x25_route_list) {
116                 rt = list_entry(entry, struct x25_route, node);
117
118                 if (rt->dev == dev)
119                         __x25_remove_route(rt);
120         }
121         write_unlock_bh(&x25_route_list_lock);
122
123         /* Remove any related forwarding */
124         x25_clear_forward_by_dev(dev);
125 }
126
127 /*
128  *      Check that the device given is a valid X.25 interface that is "up".
129  */
130 struct net_device *x25_dev_get(char *devname)
131 {
132         struct net_device *dev = dev_get_by_name(&init_net, devname);
133
134         if (dev &&
135             (!(dev->flags & IFF_UP) || (dev->type != ARPHRD_X25
136 #if defined(CONFIG_LLC) || defined(CONFIG_LLC_MODULE)
137                                         && dev->type != ARPHRD_ETHER
138 #endif
139                                         )))
140                 dev_put(dev);
141
142         return dev;
143 }
144
145 /**
146  *      x25_get_route - Find a route given an X.25 address.
147  *      @addr - address to find a route for
148  *
149  *      Find a route given an X.25 address.
150  */
151 struct x25_route *x25_get_route(struct x25_address *addr)
152 {
153         struct x25_route *rt, *use = NULL;
154         struct list_head *entry;
155
156         read_lock_bh(&x25_route_list_lock);
157
158         list_for_each(entry, &x25_route_list) {
159                 rt = list_entry(entry, struct x25_route, node);
160
161                 if (!memcmp(&rt->address, addr, rt->sigdigits)) {
162                         if (!use)
163                                 use = rt;
164                         else if (rt->sigdigits > use->sigdigits)
165                                 use = rt;
166                 }
167         }
168
169         if (use)
170                 x25_route_hold(use);
171
172         read_unlock_bh(&x25_route_list_lock);
173         return use;
174 }
175
176 /*
177  *      Handle the ioctls that control the routing functions.
178  */
179 int x25_route_ioctl(unsigned int cmd, void __user *arg)
180 {
181         struct x25_route_struct rt;
182         struct net_device *dev;
183         int rc = -EINVAL;
184
185         if (cmd != SIOCADDRT && cmd != SIOCDELRT)
186                 goto out;
187
188         rc = -EFAULT;
189         if (copy_from_user(&rt, arg, sizeof(rt)))
190                 goto out;
191
192         rc = -EINVAL;
193         if (rt.sigdigits < 0 || rt.sigdigits > 15)
194                 goto out;
195
196         dev = x25_dev_get(rt.device);
197         if (!dev)
198                 goto out;
199
200         if (cmd == SIOCADDRT)
201                 rc = x25_add_route(&rt.address, rt.sigdigits, dev);
202         else
203                 rc = x25_del_route(&rt.address, rt.sigdigits, dev);
204         dev_put(dev);
205 out:
206         return rc;
207 }
208
209 /*
210  *      Release all memory associated with X.25 routing structures.
211  */
212 void __exit x25_route_free(void)
213 {
214         struct x25_route *rt;
215         struct list_head *entry, *tmp;
216
217         write_lock_bh(&x25_route_list_lock);
218         list_for_each_safe(entry, tmp, &x25_route_list) {
219                 rt = list_entry(entry, struct x25_route, node);
220                 __x25_remove_route(rt);
221         }
222         write_unlock_bh(&x25_route_list_lock);
223 }