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 | ||
b73e9e3c | 24 | #define pr_fmt(fmt) "X25: " fmt |
25 | ||
1da177e4 LT |
26 | #include <linux/kernel.h> |
27 | #include <linux/jiffies.h> | |
28 | #include <linux/timer.h> | |
5a0e3ad6 | 29 | #include <linux/slab.h> |
1da177e4 LT |
30 | #include <linux/netdevice.h> |
31 | #include <linux/skbuff.h> | |
32 | #include <asm/uaccess.h> | |
33 | #include <linux/init.h> | |
34 | #include <net/x25.h> | |
35 | ||
5595a1a5 | 36 | LIST_HEAD(x25_neigh_list); |
37 | DEFINE_RWLOCK(x25_neigh_list_lock); | |
1da177e4 LT |
38 | |
39 | static void x25_t20timer_expiry(unsigned long); | |
40 | ||
41 | static void x25_transmit_restart_confirmation(struct x25_neigh *nb); | |
42 | static void x25_transmit_restart_request(struct x25_neigh *nb); | |
43 | ||
44 | /* | |
45 | * Linux set/reset timer routines | |
46 | */ | |
47 | static inline void x25_start_t20timer(struct x25_neigh *nb) | |
48 | { | |
49 | mod_timer(&nb->t20timer, jiffies + nb->t20); | |
50 | } | |
51 | ||
52 | static void x25_t20timer_expiry(unsigned long param) | |
53 | { | |
54 | struct x25_neigh *nb = (struct x25_neigh *)param; | |
55 | ||
56 | x25_transmit_restart_request(nb); | |
57 | ||
58 | x25_start_t20timer(nb); | |
59 | } | |
60 | ||
61 | static inline void x25_stop_t20timer(struct x25_neigh *nb) | |
62 | { | |
63 | del_timer(&nb->t20timer); | |
64 | } | |
65 | ||
66 | static inline int x25_t20timer_pending(struct x25_neigh *nb) | |
67 | { | |
68 | return timer_pending(&nb->t20timer); | |
69 | } | |
70 | ||
71 | /* | |
72 | * This handles all restart and diagnostic frames. | |
73 | */ | |
74 | void x25_link_control(struct sk_buff *skb, struct x25_neigh *nb, | |
75 | unsigned short frametype) | |
76 | { | |
77 | struct sk_buff *skbn; | |
78 | int confirm; | |
79 | ||
80 | switch (frametype) { | |
fddc5f3e JP |
81 | case X25_RESTART_REQUEST: |
82 | confirm = !x25_t20timer_pending(nb); | |
83 | x25_stop_t20timer(nb); | |
84 | nb->state = X25_LINK_STATE_3; | |
85 | if (confirm) | |
86 | x25_transmit_restart_confirmation(nb); | |
87 | break; | |
88 | ||
89 | case X25_RESTART_CONFIRMATION: | |
90 | x25_stop_t20timer(nb); | |
91 | nb->state = X25_LINK_STATE_3; | |
92 | break; | |
93 | ||
94 | case X25_DIAGNOSTIC: | |
cb101ed2 MD |
95 | if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 4)) |
96 | break; | |
97 | ||
b73e9e3c | 98 | pr_warn("diagnostic #%d - %02X %02X %02X\n", |
fddc5f3e JP |
99 | skb->data[3], skb->data[4], |
100 | skb->data[5], skb->data[6]); | |
101 | break; | |
102 | ||
103 | default: | |
b73e9e3c | 104 | pr_warn("received unknown %02X with LCI 000\n", |
fddc5f3e JP |
105 | frametype); |
106 | break; | |
1da177e4 LT |
107 | } |
108 | ||
109 | if (nb->state == X25_LINK_STATE_3) | |
110 | while ((skbn = skb_dequeue(&nb->queue)) != NULL) | |
111 | x25_send_frame(skbn, nb); | |
112 | } | |
113 | ||
114 | /* | |
115 | * This routine is called when a Restart Request is needed | |
116 | */ | |
117 | static void x25_transmit_restart_request(struct x25_neigh *nb) | |
118 | { | |
119 | unsigned char *dptr; | |
120 | int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN + 2; | |
121 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
122 | ||
123 | if (!skb) | |
124 | return; | |
125 | ||
126 | skb_reserve(skb, X25_MAX_L2_LEN); | |
127 | ||
128 | dptr = skb_put(skb, X25_STD_MIN_LEN + 2); | |
129 | ||
130 | *dptr++ = nb->extended ? X25_GFI_EXTSEQ : X25_GFI_STDSEQ; | |
131 | *dptr++ = 0x00; | |
132 | *dptr++ = X25_RESTART_REQUEST; | |
133 | *dptr++ = 0x00; | |
134 | *dptr++ = 0; | |
135 | ||
136 | skb->sk = NULL; | |
137 | ||
138 | x25_send_frame(skb, nb); | |
139 | } | |
140 | ||
141 | /* | |
142 | * This routine is called when a Restart Confirmation is needed | |
143 | */ | |
144 | static void x25_transmit_restart_confirmation(struct x25_neigh *nb) | |
145 | { | |
146 | unsigned char *dptr; | |
147 | int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN; | |
148 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
149 | ||
150 | if (!skb) | |
151 | return; | |
152 | ||
153 | skb_reserve(skb, X25_MAX_L2_LEN); | |
154 | ||
155 | dptr = skb_put(skb, X25_STD_MIN_LEN); | |
156 | ||
157 | *dptr++ = nb->extended ? X25_GFI_EXTSEQ : X25_GFI_STDSEQ; | |
158 | *dptr++ = 0x00; | |
159 | *dptr++ = X25_RESTART_CONFIRMATION; | |
160 | ||
161 | skb->sk = NULL; | |
162 | ||
163 | x25_send_frame(skb, nb); | |
164 | } | |
165 | ||
166 | /* | |
167 | * This routine is called when a Clear Request is needed outside of the context | |
168 | * of a connected socket. | |
169 | */ | |
170 | void x25_transmit_clear_request(struct x25_neigh *nb, unsigned int lci, | |
171 | unsigned char cause) | |
172 | { | |
173 | unsigned char *dptr; | |
174 | int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN + 2; | |
175 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
176 | ||
177 | if (!skb) | |
178 | return; | |
179 | ||
180 | skb_reserve(skb, X25_MAX_L2_LEN); | |
181 | ||
182 | dptr = skb_put(skb, X25_STD_MIN_LEN + 2); | |
183 | ||
184 | *dptr++ = ((lci >> 8) & 0x0F) | (nb->extended ? | |
185 | X25_GFI_EXTSEQ : | |
186 | X25_GFI_STDSEQ); | |
187 | *dptr++ = (lci >> 0) & 0xFF; | |
188 | *dptr++ = X25_CLEAR_REQUEST; | |
189 | *dptr++ = cause; | |
190 | *dptr++ = 0x00; | |
191 | ||
192 | skb->sk = NULL; | |
193 | ||
194 | x25_send_frame(skb, nb); | |
195 | } | |
196 | ||
197 | void x25_transmit_link(struct sk_buff *skb, struct x25_neigh *nb) | |
198 | { | |
199 | switch (nb->state) { | |
fddc5f3e JP |
200 | case X25_LINK_STATE_0: |
201 | skb_queue_tail(&nb->queue, skb); | |
202 | nb->state = X25_LINK_STATE_1; | |
203 | x25_establish_link(nb); | |
204 | break; | |
205 | case X25_LINK_STATE_1: | |
206 | case X25_LINK_STATE_2: | |
207 | skb_queue_tail(&nb->queue, skb); | |
208 | break; | |
209 | case X25_LINK_STATE_3: | |
210 | x25_send_frame(skb, nb); | |
211 | break; | |
1da177e4 LT |
212 | } |
213 | } | |
214 | ||
215 | /* | |
216 | * Called when the link layer has become established. | |
217 | */ | |
218 | void x25_link_established(struct x25_neigh *nb) | |
219 | { | |
220 | switch (nb->state) { | |
fddc5f3e JP |
221 | case X25_LINK_STATE_0: |
222 | nb->state = X25_LINK_STATE_2; | |
223 | break; | |
224 | case X25_LINK_STATE_1: | |
225 | x25_transmit_restart_request(nb); | |
226 | nb->state = X25_LINK_STATE_2; | |
227 | x25_start_t20timer(nb); | |
228 | break; | |
1da177e4 LT |
229 | } |
230 | } | |
231 | ||
232 | /* | |
233 | * Called when the link layer has terminated, or an establishment | |
234 | * request has failed. | |
235 | */ | |
236 | ||
237 | void x25_link_terminated(struct x25_neigh *nb) | |
238 | { | |
239 | nb->state = X25_LINK_STATE_0; | |
240 | /* Out of order: clear existing virtual calls (X.25 03/93 4.6.3) */ | |
241 | x25_kill_by_neigh(nb); | |
242 | } | |
243 | ||
244 | /* | |
245 | * Add a new device. | |
246 | */ | |
247 | void x25_link_device_up(struct net_device *dev) | |
248 | { | |
249 | struct x25_neigh *nb = kmalloc(sizeof(*nb), GFP_ATOMIC); | |
250 | ||
251 | if (!nb) | |
252 | return; | |
253 | ||
254 | skb_queue_head_init(&nb->queue); | |
b24b8a24 | 255 | setup_timer(&nb->t20timer, x25_t20timer_expiry, (unsigned long)nb); |
1da177e4 LT |
256 | |
257 | dev_hold(dev); | |
258 | nb->dev = dev; | |
259 | nb->state = X25_LINK_STATE_0; | |
260 | nb->extended = 0; | |
261 | /* | |
262 | * Enables negotiation | |
263 | */ | |
264 | nb->global_facil_mask = X25_MASK_REVERSE | | |
265 | X25_MASK_THROUGHPUT | | |
266 | X25_MASK_PACKET_SIZE | | |
267 | X25_MASK_WINDOW_SIZE; | |
268 | nb->t20 = sysctl_x25_restart_request_timeout; | |
269 | atomic_set(&nb->refcnt, 1); | |
270 | ||
271 | write_lock_bh(&x25_neigh_list_lock); | |
272 | list_add(&nb->node, &x25_neigh_list); | |
273 | write_unlock_bh(&x25_neigh_list_lock); | |
274 | } | |
275 | ||
276 | /** | |
277 | * __x25_remove_neigh - remove neighbour from x25_neigh_list | |
278 | * @nb - neigh to remove | |
279 | * | |
280 | * Remove neighbour from x25_neigh_list. If it was there. | |
281 | * Caller must hold x25_neigh_list_lock. | |
282 | */ | |
283 | static void __x25_remove_neigh(struct x25_neigh *nb) | |
284 | { | |
285 | skb_queue_purge(&nb->queue); | |
286 | x25_stop_t20timer(nb); | |
287 | ||
288 | if (nb->node.next) { | |
289 | list_del(&nb->node); | |
290 | x25_neigh_put(nb); | |
291 | } | |
292 | } | |
293 | ||
294 | /* | |
295 | * A device has been removed, remove its links. | |
296 | */ | |
297 | void x25_link_device_down(struct net_device *dev) | |
298 | { | |
299 | struct x25_neigh *nb; | |
300 | struct list_head *entry, *tmp; | |
301 | ||
302 | write_lock_bh(&x25_neigh_list_lock); | |
303 | ||
304 | list_for_each_safe(entry, tmp, &x25_neigh_list) { | |
305 | nb = list_entry(entry, struct x25_neigh, node); | |
306 | ||
307 | if (nb->dev == dev) { | |
308 | __x25_remove_neigh(nb); | |
309 | dev_put(dev); | |
310 | } | |
311 | } | |
312 | ||
313 | write_unlock_bh(&x25_neigh_list_lock); | |
314 | } | |
315 | ||
316 | /* | |
317 | * Given a device, return the neighbour address. | |
318 | */ | |
319 | struct x25_neigh *x25_get_neigh(struct net_device *dev) | |
320 | { | |
321 | struct x25_neigh *nb, *use = NULL; | |
322 | struct list_head *entry; | |
323 | ||
324 | read_lock_bh(&x25_neigh_list_lock); | |
325 | list_for_each(entry, &x25_neigh_list) { | |
326 | nb = list_entry(entry, struct x25_neigh, node); | |
327 | ||
328 | if (nb->dev == dev) { | |
329 | use = nb; | |
330 | break; | |
331 | } | |
332 | } | |
333 | ||
334 | if (use) | |
335 | x25_neigh_hold(use); | |
336 | read_unlock_bh(&x25_neigh_list_lock); | |
337 | return use; | |
338 | } | |
339 | ||
340 | /* | |
341 | * Handle the ioctls that control the subscription functions. | |
342 | */ | |
343 | int x25_subscr_ioctl(unsigned int cmd, void __user *arg) | |
344 | { | |
345 | struct x25_subscrip_struct x25_subscr; | |
346 | struct x25_neigh *nb; | |
347 | struct net_device *dev; | |
348 | int rc = -EINVAL; | |
349 | ||
350 | if (cmd != SIOCX25GSUBSCRIP && cmd != SIOCX25SSUBSCRIP) | |
351 | goto out; | |
352 | ||
353 | rc = -EFAULT; | |
354 | if (copy_from_user(&x25_subscr, arg, sizeof(x25_subscr))) | |
355 | goto out; | |
356 | ||
357 | rc = -EINVAL; | |
358 | if ((dev = x25_dev_get(x25_subscr.device)) == NULL) | |
359 | goto out; | |
360 | ||
361 | if ((nb = x25_get_neigh(dev)) == NULL) | |
362 | goto out_dev_put; | |
363 | ||
364 | dev_put(dev); | |
365 | ||
366 | if (cmd == SIOCX25GSUBSCRIP) { | |
5595a1a5 | 367 | read_lock_bh(&x25_neigh_list_lock); |
1da177e4 LT |
368 | x25_subscr.extended = nb->extended; |
369 | x25_subscr.global_facil_mask = nb->global_facil_mask; | |
5595a1a5 | 370 | read_unlock_bh(&x25_neigh_list_lock); |
1da177e4 LT |
371 | rc = copy_to_user(arg, &x25_subscr, |
372 | sizeof(x25_subscr)) ? -EFAULT : 0; | |
373 | } else { | |
374 | rc = -EINVAL; | |
375 | if (!(x25_subscr.extended && x25_subscr.extended != 1)) { | |
376 | rc = 0; | |
5595a1a5 | 377 | write_lock_bh(&x25_neigh_list_lock); |
1da177e4 LT |
378 | nb->extended = x25_subscr.extended; |
379 | nb->global_facil_mask = x25_subscr.global_facil_mask; | |
5595a1a5 | 380 | write_unlock_bh(&x25_neigh_list_lock); |
1da177e4 LT |
381 | } |
382 | } | |
383 | x25_neigh_put(nb); | |
384 | out: | |
385 | return rc; | |
386 | out_dev_put: | |
387 | dev_put(dev); | |
388 | goto out; | |
389 | } | |
390 | ||
391 | ||
392 | /* | |
393 | * Release all memory associated with X.25 neighbour structures. | |
394 | */ | |
395 | void __exit x25_link_free(void) | |
396 | { | |
397 | struct x25_neigh *nb; | |
398 | struct list_head *entry, *tmp; | |
399 | ||
400 | write_lock_bh(&x25_neigh_list_lock); | |
401 | ||
402 | list_for_each_safe(entry, tmp, &x25_neigh_list) { | |
96642d42 DM |
403 | struct net_device *dev; |
404 | ||
1da177e4 | 405 | nb = list_entry(entry, struct x25_neigh, node); |
96642d42 | 406 | dev = nb->dev; |
1da177e4 | 407 | __x25_remove_neigh(nb); |
96642d42 | 408 | dev_put(dev); |
1da177e4 LT |
409 | } |
410 | write_unlock_bh(&x25_neigh_list_lock); | |
411 | } |