Commit | Line | Data |
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1da177e4 LT |
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 | |
f8e1d201 | 6 | * screw up. It might even work. |
1da177e4 LT |
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 | * X.25 002 Jonathan Naylor New timer architecture. | |
f8e1d201 | 19 | * mar/20/00 Daniela Squassoni Disabling/enabling of facilities |
1da177e4 LT |
20 | * negotiation. |
21 | * 2000-09-04 Henner Eisen dev_hold() / dev_put() for x25_neigh. | |
22 | */ | |
23 | ||
24 | #include <linux/kernel.h> | |
25 | #include <linux/jiffies.h> | |
26 | #include <linux/timer.h> | |
27 | #include <linux/netdevice.h> | |
28 | #include <linux/skbuff.h> | |
29 | #include <asm/uaccess.h> | |
30 | #include <linux/init.h> | |
31 | #include <net/x25.h> | |
32 | ||
0e3cf7e9 | 33 | static LIST_HEAD(x25_neigh_list); |
1da177e4 LT |
34 | static DEFINE_RWLOCK(x25_neigh_list_lock); |
35 | ||
36 | static void x25_t20timer_expiry(unsigned long); | |
37 | ||
38 | static void x25_transmit_restart_confirmation(struct x25_neigh *nb); | |
39 | static void x25_transmit_restart_request(struct x25_neigh *nb); | |
40 | ||
41 | /* | |
42 | * Linux set/reset timer routines | |
43 | */ | |
44 | static inline void x25_start_t20timer(struct x25_neigh *nb) | |
45 | { | |
46 | mod_timer(&nb->t20timer, jiffies + nb->t20); | |
47 | } | |
48 | ||
49 | static void x25_t20timer_expiry(unsigned long param) | |
50 | { | |
51 | struct x25_neigh *nb = (struct x25_neigh *)param; | |
52 | ||
53 | x25_transmit_restart_request(nb); | |
54 | ||
55 | x25_start_t20timer(nb); | |
56 | } | |
57 | ||
58 | static inline void x25_stop_t20timer(struct x25_neigh *nb) | |
59 | { | |
60 | del_timer(&nb->t20timer); | |
61 | } | |
62 | ||
63 | static inline int x25_t20timer_pending(struct x25_neigh *nb) | |
64 | { | |
65 | return timer_pending(&nb->t20timer); | |
66 | } | |
67 | ||
68 | /* | |
69 | * This handles all restart and diagnostic frames. | |
70 | */ | |
71 | void x25_link_control(struct sk_buff *skb, struct x25_neigh *nb, | |
72 | unsigned short frametype) | |
73 | { | |
74 | struct sk_buff *skbn; | |
75 | int confirm; | |
76 | ||
77 | switch (frametype) { | |
78 | case X25_RESTART_REQUEST: | |
79 | confirm = !x25_t20timer_pending(nb); | |
80 | x25_stop_t20timer(nb); | |
81 | nb->state = X25_LINK_STATE_3; | |
82 | if (confirm) | |
83 | x25_transmit_restart_confirmation(nb); | |
84 | break; | |
85 | ||
86 | case X25_RESTART_CONFIRMATION: | |
87 | x25_stop_t20timer(nb); | |
88 | nb->state = X25_LINK_STATE_3; | |
89 | break; | |
90 | ||
91 | case X25_DIAGNOSTIC: | |
92 | printk(KERN_WARNING "x25: diagnostic #%d - " | |
93 | "%02X %02X %02X\n", | |
94 | skb->data[3], skb->data[4], | |
95 | skb->data[5], skb->data[6]); | |
96 | break; | |
f8e1d201 | 97 | |
1da177e4 LT |
98 | default: |
99 | printk(KERN_WARNING "x25: received unknown %02X " | |
100 | "with LCI 000\n", frametype); | |
101 | break; | |
102 | } | |
103 | ||
104 | if (nb->state == X25_LINK_STATE_3) | |
105 | while ((skbn = skb_dequeue(&nb->queue)) != NULL) | |
106 | x25_send_frame(skbn, nb); | |
107 | } | |
108 | ||
109 | /* | |
110 | * This routine is called when a Restart Request is needed | |
111 | */ | |
112 | static void x25_transmit_restart_request(struct x25_neigh *nb) | |
113 | { | |
114 | unsigned char *dptr; | |
115 | int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN + 2; | |
116 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
117 | ||
118 | if (!skb) | |
119 | return; | |
120 | ||
121 | skb_reserve(skb, X25_MAX_L2_LEN); | |
122 | ||
123 | dptr = skb_put(skb, X25_STD_MIN_LEN + 2); | |
124 | ||
125 | *dptr++ = nb->extended ? X25_GFI_EXTSEQ : X25_GFI_STDSEQ; | |
126 | *dptr++ = 0x00; | |
127 | *dptr++ = X25_RESTART_REQUEST; | |
128 | *dptr++ = 0x00; | |
129 | *dptr++ = 0; | |
130 | ||
131 | skb->sk = NULL; | |
132 | ||
133 | x25_send_frame(skb, nb); | |
134 | } | |
135 | ||
136 | /* | |
137 | * This routine is called when a Restart Confirmation is needed | |
138 | */ | |
139 | static void x25_transmit_restart_confirmation(struct x25_neigh *nb) | |
140 | { | |
141 | unsigned char *dptr; | |
142 | int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN; | |
143 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
144 | ||
145 | if (!skb) | |
146 | return; | |
147 | ||
148 | skb_reserve(skb, X25_MAX_L2_LEN); | |
149 | ||
150 | dptr = skb_put(skb, X25_STD_MIN_LEN); | |
151 | ||
152 | *dptr++ = nb->extended ? X25_GFI_EXTSEQ : X25_GFI_STDSEQ; | |
153 | *dptr++ = 0x00; | |
154 | *dptr++ = X25_RESTART_CONFIRMATION; | |
155 | ||
156 | skb->sk = NULL; | |
157 | ||
158 | x25_send_frame(skb, nb); | |
159 | } | |
160 | ||
161 | /* | |
162 | * This routine is called when a Clear Request is needed outside of the context | |
163 | * of a connected socket. | |
164 | */ | |
165 | void x25_transmit_clear_request(struct x25_neigh *nb, unsigned int lci, | |
166 | unsigned char cause) | |
167 | { | |
168 | unsigned char *dptr; | |
169 | int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN + 2; | |
170 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
171 | ||
172 | if (!skb) | |
173 | return; | |
174 | ||
175 | skb_reserve(skb, X25_MAX_L2_LEN); | |
176 | ||
177 | dptr = skb_put(skb, X25_STD_MIN_LEN + 2); | |
178 | ||
179 | *dptr++ = ((lci >> 8) & 0x0F) | (nb->extended ? | |
180 | X25_GFI_EXTSEQ : | |
181 | X25_GFI_STDSEQ); | |
182 | *dptr++ = (lci >> 0) & 0xFF; | |
183 | *dptr++ = X25_CLEAR_REQUEST; | |
184 | *dptr++ = cause; | |
185 | *dptr++ = 0x00; | |
186 | ||
187 | skb->sk = NULL; | |
188 | ||
189 | x25_send_frame(skb, nb); | |
190 | } | |
191 | ||
192 | void x25_transmit_link(struct sk_buff *skb, struct x25_neigh *nb) | |
193 | { | |
194 | switch (nb->state) { | |
195 | case X25_LINK_STATE_0: | |
196 | skb_queue_tail(&nb->queue, skb); | |
197 | nb->state = X25_LINK_STATE_1; | |
198 | x25_establish_link(nb); | |
199 | break; | |
200 | case X25_LINK_STATE_1: | |
201 | case X25_LINK_STATE_2: | |
202 | skb_queue_tail(&nb->queue, skb); | |
203 | break; | |
204 | case X25_LINK_STATE_3: | |
205 | x25_send_frame(skb, nb); | |
206 | break; | |
207 | } | |
208 | } | |
209 | ||
210 | /* | |
211 | * Called when the link layer has become established. | |
212 | */ | |
213 | void x25_link_established(struct x25_neigh *nb) | |
214 | { | |
215 | switch (nb->state) { | |
216 | case X25_LINK_STATE_0: | |
217 | nb->state = X25_LINK_STATE_2; | |
218 | break; | |
219 | case X25_LINK_STATE_1: | |
220 | x25_transmit_restart_request(nb); | |
221 | nb->state = X25_LINK_STATE_2; | |
222 | x25_start_t20timer(nb); | |
223 | break; | |
224 | } | |
225 | } | |
226 | ||
227 | /* | |
228 | * Called when the link layer has terminated, or an establishment | |
229 | * request has failed. | |
230 | */ | |
231 | ||
232 | void x25_link_terminated(struct x25_neigh *nb) | |
233 | { | |
234 | nb->state = X25_LINK_STATE_0; | |
235 | /* Out of order: clear existing virtual calls (X.25 03/93 4.6.3) */ | |
236 | x25_kill_by_neigh(nb); | |
237 | } | |
238 | ||
239 | /* | |
240 | * Add a new device. | |
241 | */ | |
242 | void x25_link_device_up(struct net_device *dev) | |
243 | { | |
244 | struct x25_neigh *nb = kmalloc(sizeof(*nb), GFP_ATOMIC); | |
245 | ||
246 | if (!nb) | |
247 | return; | |
248 | ||
249 | skb_queue_head_init(&nb->queue); | |
b24b8a24 | 250 | setup_timer(&nb->t20timer, x25_t20timer_expiry, (unsigned long)nb); |
1da177e4 LT |
251 | |
252 | dev_hold(dev); | |
253 | nb->dev = dev; | |
254 | nb->state = X25_LINK_STATE_0; | |
255 | nb->extended = 0; | |
256 | /* | |
257 | * Enables negotiation | |
258 | */ | |
259 | nb->global_facil_mask = X25_MASK_REVERSE | | |
260 | X25_MASK_THROUGHPUT | | |
261 | X25_MASK_PACKET_SIZE | | |
262 | X25_MASK_WINDOW_SIZE; | |
263 | nb->t20 = sysctl_x25_restart_request_timeout; | |
264 | atomic_set(&nb->refcnt, 1); | |
265 | ||
266 | write_lock_bh(&x25_neigh_list_lock); | |
267 | list_add(&nb->node, &x25_neigh_list); | |
268 | write_unlock_bh(&x25_neigh_list_lock); | |
269 | } | |
270 | ||
271 | /** | |
272 | * __x25_remove_neigh - remove neighbour from x25_neigh_list | |
273 | * @nb - neigh to remove | |
274 | * | |
275 | * Remove neighbour from x25_neigh_list. If it was there. | |
276 | * Caller must hold x25_neigh_list_lock. | |
277 | */ | |
278 | static void __x25_remove_neigh(struct x25_neigh *nb) | |
279 | { | |
280 | skb_queue_purge(&nb->queue); | |
281 | x25_stop_t20timer(nb); | |
282 | ||
283 | if (nb->node.next) { | |
284 | list_del(&nb->node); | |
285 | x25_neigh_put(nb); | |
286 | } | |
287 | } | |
288 | ||
289 | /* | |
290 | * A device has been removed, remove its links. | |
291 | */ | |
292 | void x25_link_device_down(struct net_device *dev) | |
293 | { | |
294 | struct x25_neigh *nb; | |
295 | struct list_head *entry, *tmp; | |
296 | ||
297 | write_lock_bh(&x25_neigh_list_lock); | |
298 | ||
299 | list_for_each_safe(entry, tmp, &x25_neigh_list) { | |
300 | nb = list_entry(entry, struct x25_neigh, node); | |
301 | ||
302 | if (nb->dev == dev) { | |
303 | __x25_remove_neigh(nb); | |
304 | dev_put(dev); | |
305 | } | |
306 | } | |
307 | ||
308 | write_unlock_bh(&x25_neigh_list_lock); | |
309 | } | |
310 | ||
311 | /* | |
312 | * Given a device, return the neighbour address. | |
313 | */ | |
314 | struct x25_neigh *x25_get_neigh(struct net_device *dev) | |
315 | { | |
316 | struct x25_neigh *nb, *use = NULL; | |
317 | struct list_head *entry; | |
318 | ||
319 | read_lock_bh(&x25_neigh_list_lock); | |
320 | list_for_each(entry, &x25_neigh_list) { | |
321 | nb = list_entry(entry, struct x25_neigh, node); | |
322 | ||
323 | if (nb->dev == dev) { | |
324 | use = nb; | |
325 | break; | |
326 | } | |
327 | } | |
328 | ||
329 | if (use) | |
330 | x25_neigh_hold(use); | |
331 | read_unlock_bh(&x25_neigh_list_lock); | |
332 | return use; | |
333 | } | |
334 | ||
335 | /* | |
336 | * Handle the ioctls that control the subscription functions. | |
337 | */ | |
338 | int x25_subscr_ioctl(unsigned int cmd, void __user *arg) | |
339 | { | |
340 | struct x25_subscrip_struct x25_subscr; | |
341 | struct x25_neigh *nb; | |
342 | struct net_device *dev; | |
343 | int rc = -EINVAL; | |
344 | ||
345 | if (cmd != SIOCX25GSUBSCRIP && cmd != SIOCX25SSUBSCRIP) | |
346 | goto out; | |
347 | ||
348 | rc = -EFAULT; | |
349 | if (copy_from_user(&x25_subscr, arg, sizeof(x25_subscr))) | |
350 | goto out; | |
351 | ||
352 | rc = -EINVAL; | |
353 | if ((dev = x25_dev_get(x25_subscr.device)) == NULL) | |
354 | goto out; | |
355 | ||
356 | if ((nb = x25_get_neigh(dev)) == NULL) | |
357 | goto out_dev_put; | |
358 | ||
359 | dev_put(dev); | |
360 | ||
361 | if (cmd == SIOCX25GSUBSCRIP) { | |
362 | x25_subscr.extended = nb->extended; | |
363 | x25_subscr.global_facil_mask = nb->global_facil_mask; | |
364 | rc = copy_to_user(arg, &x25_subscr, | |
365 | sizeof(x25_subscr)) ? -EFAULT : 0; | |
366 | } else { | |
367 | rc = -EINVAL; | |
368 | if (!(x25_subscr.extended && x25_subscr.extended != 1)) { | |
369 | rc = 0; | |
370 | nb->extended = x25_subscr.extended; | |
371 | nb->global_facil_mask = x25_subscr.global_facil_mask; | |
372 | } | |
373 | } | |
374 | x25_neigh_put(nb); | |
375 | out: | |
376 | return rc; | |
377 | out_dev_put: | |
378 | dev_put(dev); | |
379 | goto out; | |
380 | } | |
381 | ||
382 | ||
383 | /* | |
384 | * Release all memory associated with X.25 neighbour structures. | |
385 | */ | |
386 | void __exit x25_link_free(void) | |
387 | { | |
388 | struct x25_neigh *nb; | |
389 | struct list_head *entry, *tmp; | |
390 | ||
391 | write_lock_bh(&x25_neigh_list_lock); | |
392 | ||
393 | list_for_each_safe(entry, tmp, &x25_neigh_list) { | |
394 | nb = list_entry(entry, struct x25_neigh, node); | |
395 | __x25_remove_neigh(nb); | |
396 | } | |
397 | write_unlock_bh(&x25_neigh_list_lock); | |
398 | } |