1 /*
2  *	X.25 Packet Layer release 002
3  *
4  *	This is ALPHA test software. This code may break your machine, randomly fail to work with new
5  *	releases, misbehave and/or generally screw up. It might even work.
6  *
7  *	This code REQUIRES 2.1.15 or higher
8  *
9  *	This module:
10  *		This module is free software; you can redistribute it and/or
11  *		modify it under the terms of the GNU General Public License
12  *		as published by the Free Software Foundation; either version
13  *		2 of the License, or (at your option) any later version.
14  *
15  *	History
16  *	X.25 001	Jonathan Naylor	Started coding.
17  */
18 
19 #include <linux/config.h>
20 #include <linux/errno.h>
21 #include <linux/types.h>
22 #include <linux/socket.h>
23 #include <linux/in.h>
24 #include <linux/kernel.h>
25 #include <linux/sched.h>
26 #include <linux/timer.h>
27 #include <linux/string.h>
28 #include <linux/sockios.h>
29 #include <linux/net.h>
30 #include <linux/inet.h>
31 #include <linux/netdevice.h>
32 #include <net/arp.h>
33 #include <linux/if_arp.h>
34 #include <linux/skbuff.h>
35 #include <net/sock.h>
36 #include <asm/segment.h>
37 #include <asm/system.h>
38 #include <asm/uaccess.h>
39 #include <linux/fcntl.h>
40 #include <linux/termios.h>	/* For TIOCINQ/OUTQ */
41 #include <linux/mm.h>
42 #include <linux/interrupt.h>
43 #include <linux/notifier.h>
44 #include <linux/init.h>
45 #include <net/x25.h>
46 
47 static struct x25_route *x25_route_list /* = NULL initially */;
48 
49 /*
50  *	Add a new route.
51  */
x25_add_route(x25_address * address,unsigned int sigdigits,struct net_device * dev)52 static int x25_add_route(x25_address *address, unsigned int sigdigits, struct net_device *dev)
53 {
54 	struct x25_route *x25_route;
55 	unsigned long flags;
56 
57 	for (x25_route = x25_route_list; x25_route != NULL; x25_route = x25_route->next)
58 		if (memcmp(&x25_route->address, address, sigdigits) == 0 && x25_route->sigdigits == sigdigits)
59 			return -EINVAL;
60 
61 	if ((x25_route = kmalloc(sizeof(*x25_route), GFP_ATOMIC)) == NULL)
62 		return -ENOMEM;
63 
64 	strcpy(x25_route->address.x25_addr, "000000000000000");
65 	memcpy(x25_route->address.x25_addr, address->x25_addr, sigdigits);
66 
67 	x25_route->sigdigits = sigdigits;
68 	x25_route->dev       = dev;
69 
70 	save_flags(flags); cli();
71 	x25_route->next = x25_route_list;
72 	x25_route_list  = x25_route;
73 	restore_flags(flags);
74 
75 	return 0;
76 }
77 
x25_remove_route(struct x25_route * x25_route)78 static void x25_remove_route(struct x25_route *x25_route)
79 {
80 	struct x25_route *s;
81 	unsigned long flags;
82 
83 	save_flags(flags);
84 	cli();
85 
86 	if ((s = x25_route_list) == x25_route) {
87 		x25_route_list = x25_route->next;
88 		restore_flags(flags);
89 		kfree(x25_route);
90 		return;
91 	}
92 
93 	while (s != NULL && s->next != NULL) {
94 		if (s->next == x25_route) {
95 			s->next = x25_route->next;
96 			restore_flags(flags);
97 			kfree(x25_route);
98 			return;
99 		}
100 
101 		s = s->next;
102 	}
103 
104 	restore_flags(flags);
105 }
106 
x25_del_route(x25_address * address,unsigned int sigdigits,struct net_device * dev)107 static int x25_del_route(x25_address *address, unsigned int sigdigits, struct net_device *dev)
108 {
109 	struct x25_route *x25_route;
110 
111 	for (x25_route = x25_route_list; x25_route != NULL; x25_route = x25_route->next) {
112 		if (memcmp(&x25_route->address, address, sigdigits) == 0 && x25_route->sigdigits == sigdigits && x25_route->dev == dev) {
113 			x25_remove_route(x25_route);
114 			return 0;
115 		}
116 	}
117 
118 	return -EINVAL;
119 }
120 
121 /*
122  *	A device has been removed, remove its routes.
123  */
x25_route_device_down(struct net_device * dev)124 void x25_route_device_down(struct net_device *dev)
125 {
126 	struct x25_route *route, *x25_route = x25_route_list;
127 
128 	while (x25_route != NULL) {
129 		route     = x25_route;
130 		x25_route = x25_route->next;
131 
132 		if (route->dev == dev)
133 			x25_remove_route(route);
134 	}
135 }
136 
137 /*
138  *	Check that the device given is a valid X.25 interface that is "up".
139  */
x25_dev_get(char * devname)140 struct net_device *x25_dev_get(char *devname)
141 {
142 	struct net_device *dev;
143 
144 	if ((dev = dev_get_by_name(devname)) == NULL)
145 		return NULL;
146 
147 	if ((dev->flags & IFF_UP) && (dev->type == ARPHRD_X25
148 #if defined(CONFIG_LLC) || defined(CONFIG_LLC_MODULE)
149 	   || dev->type == ARPHRD_ETHER
150 #endif
151 	   ))
152 		return dev;
153 
154 	dev_put(dev);
155 
156 	return NULL;
157 }
158 
159 /*
160  *	Find a device given an X.25 address.
161  */
x25_get_route(x25_address * addr)162 struct net_device *x25_get_route(x25_address *addr)
163 {
164 	struct x25_route *route, *use = NULL;
165 
166 	for (route = x25_route_list; route != NULL; route = route->next) {
167 		if (memcmp(&route->address, addr, route->sigdigits) == 0) {
168 			if (use == NULL) {
169 				use = route;
170 			} else {
171 				if (route->sigdigits > use->sigdigits)
172 					use = route;
173 			}
174 		}
175 	}
176 
177 	return (use != NULL) ? use->dev : NULL;
178 }
179 
180 /*
181  *	Handle the ioctls that control the routing functions.
182  */
x25_route_ioctl(unsigned int cmd,void * arg)183 int x25_route_ioctl(unsigned int cmd, void *arg)
184 {
185 	struct x25_route_struct x25_route;
186 	struct net_device *dev;
187 	int err;
188 
189 	switch (cmd) {
190 
191 		case SIOCADDRT:
192 			if (copy_from_user(&x25_route, arg, sizeof(struct x25_route_struct)))
193 				return -EFAULT;
194 			if (x25_route.sigdigits < 0 || x25_route.sigdigits > 15)
195 				return -EINVAL;
196 			if ((dev = x25_dev_get(x25_route.device)) == NULL)
197 				return -EINVAL;
198 			err = x25_add_route(&x25_route.address, x25_route.sigdigits, dev);
199 			dev_put(dev);
200 			return err;
201 
202 		case SIOCDELRT:
203 			if (copy_from_user(&x25_route, arg, sizeof(struct x25_route_struct)))
204 				return -EFAULT;
205 			if (x25_route.sigdigits < 0 || x25_route.sigdigits > 15)
206 				return -EINVAL;
207 			if ((dev = x25_dev_get(x25_route.device)) == NULL)
208 				return -EINVAL;
209 			err = x25_del_route(&x25_route.address, x25_route.sigdigits, dev);
210 			dev_put(dev);
211 			return err;
212 
213 		default:
214 			return -EINVAL;
215 	}
216 
217 	return 0;
218 }
219 
x25_routes_get_info(char * buffer,char ** start,off_t offset,int length)220 int x25_routes_get_info(char *buffer, char **start, off_t offset, int length)
221 {
222 	struct x25_route *x25_route;
223 	int len     = 0;
224 	off_t pos   = 0;
225 	off_t begin = 0;
226 
227 	cli();
228 
229 	len += sprintf(buffer, "address          digits  device\n");
230 
231 	for (x25_route = x25_route_list; x25_route != NULL; x25_route = x25_route->next) {
232 		len += sprintf(buffer + len, "%-15s  %-6d  %-5s\n",
233 			x25_route->address.x25_addr,
234 			x25_route->sigdigits,
235 			(x25_route->dev != NULL) ? x25_route->dev->name : "???");
236 
237 		pos = begin + len;
238 
239 		if (pos < offset) {
240 			len   = 0;
241 			begin = pos;
242 		}
243 
244 		if (pos > offset + length)
245 			break;
246 	}
247 
248 	sti();
249 
250 	*start = buffer + (offset - begin);
251 	len   -= (offset - begin);
252 
253 	if (len > length) len = length;
254 
255 	return len;
256 }
257 
258 /*
259  *	Release all memory associated with X.25 routing structures.
260  */
x25_route_free(void)261 void __exit x25_route_free(void)
262 {
263 	struct x25_route *route, *x25_route = x25_route_list;
264 
265 	while (x25_route != NULL) {
266 		route     = x25_route;
267 		x25_route = x25_route->next;
268 
269 		x25_remove_route(route);
270 	}
271 }
272