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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * xfrm_state.c | |
3 | * | |
4 | * Changes: | |
5 | * Mitsuru KANDA @USAGI | |
6 | * Kazunori MIYAZAWA @USAGI | |
7 | * Kunihiro Ishiguro <kunihiro@ipinfusion.com> | |
8 | * IPv6 support | |
9 | * YOSHIFUJI Hideaki @USAGI | |
10 | * Split up af-specific functions | |
11 | * Derek Atkins <derek@ihtfp.com> | |
12 | * Add UDP Encapsulation | |
13 | * | |
14 | */ | |
15 | ||
16 | #include <linux/workqueue.h> | |
17 | #include <net/xfrm.h> | |
18 | #include <linux/pfkeyv2.h> | |
19 | #include <linux/ipsec.h> | |
20 | #include <linux/module.h> | |
21 | #include <asm/uaccess.h> | |
22 | ||
23 | /* Each xfrm_state may be linked to two tables: | |
24 | ||
25 | 1. Hash table by (spi,daddr,ah/esp) to find SA by SPI. (input,ctl) | |
26 | 2. Hash table by daddr to find what SAs exist for given | |
27 | destination/tunnel endpoint. (output) | |
28 | */ | |
29 | ||
30 | static DEFINE_SPINLOCK(xfrm_state_lock); | |
31 | ||
32 | /* Hash table to find appropriate SA towards given target (endpoint | |
33 | * of tunnel or destination of transport mode) allowed by selector. | |
34 | * | |
35 | * Main use is finding SA after policy selected tunnel or transport mode. | |
36 | * Also, it can be used by ah/esp icmp error handler to find offending SA. | |
37 | */ | |
38 | static struct list_head xfrm_state_bydst[XFRM_DST_HSIZE]; | |
39 | static struct list_head xfrm_state_byspi[XFRM_DST_HSIZE]; | |
40 | ||
41 | DECLARE_WAIT_QUEUE_HEAD(km_waitq); | |
42 | EXPORT_SYMBOL(km_waitq); | |
43 | ||
44 | static DEFINE_RWLOCK(xfrm_state_afinfo_lock); | |
45 | static struct xfrm_state_afinfo *xfrm_state_afinfo[NPROTO]; | |
46 | ||
47 | static struct work_struct xfrm_state_gc_work; | |
48 | static struct list_head xfrm_state_gc_list = LIST_HEAD_INIT(xfrm_state_gc_list); | |
49 | static DEFINE_SPINLOCK(xfrm_state_gc_lock); | |
50 | ||
51 | static int xfrm_state_gc_flush_bundles; | |
52 | ||
53 | static void __xfrm_state_delete(struct xfrm_state *x); | |
54 | ||
55 | static struct xfrm_state_afinfo *xfrm_state_get_afinfo(unsigned short family); | |
56 | static void xfrm_state_put_afinfo(struct xfrm_state_afinfo *afinfo); | |
57 | ||
58 | static int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol); | |
59 | static void km_state_expired(struct xfrm_state *x, int hard); | |
60 | ||
61 | static void xfrm_state_gc_destroy(struct xfrm_state *x) | |
62 | { | |
63 | if (del_timer(&x->timer)) | |
64 | BUG(); | |
65 | if (x->aalg) | |
66 | kfree(x->aalg); | |
67 | if (x->ealg) | |
68 | kfree(x->ealg); | |
69 | if (x->calg) | |
70 | kfree(x->calg); | |
71 | if (x->encap) | |
72 | kfree(x->encap); | |
73 | if (x->type) { | |
74 | x->type->destructor(x); | |
75 | xfrm_put_type(x->type); | |
76 | } | |
77 | kfree(x); | |
78 | } | |
79 | ||
80 | static void xfrm_state_gc_task(void *data) | |
81 | { | |
82 | struct xfrm_state *x; | |
83 | struct list_head *entry, *tmp; | |
84 | struct list_head gc_list = LIST_HEAD_INIT(gc_list); | |
85 | ||
86 | if (xfrm_state_gc_flush_bundles) { | |
87 | xfrm_state_gc_flush_bundles = 0; | |
88 | xfrm_flush_bundles(); | |
89 | } | |
90 | ||
91 | spin_lock_bh(&xfrm_state_gc_lock); | |
92 | list_splice_init(&xfrm_state_gc_list, &gc_list); | |
93 | spin_unlock_bh(&xfrm_state_gc_lock); | |
94 | ||
95 | list_for_each_safe(entry, tmp, &gc_list) { | |
96 | x = list_entry(entry, struct xfrm_state, bydst); | |
97 | xfrm_state_gc_destroy(x); | |
98 | } | |
99 | wake_up(&km_waitq); | |
100 | } | |
101 | ||
102 | static inline unsigned long make_jiffies(long secs) | |
103 | { | |
104 | if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) | |
105 | return MAX_SCHEDULE_TIMEOUT-1; | |
106 | else | |
107 | return secs*HZ; | |
108 | } | |
109 | ||
110 | static void xfrm_timer_handler(unsigned long data) | |
111 | { | |
112 | struct xfrm_state *x = (struct xfrm_state*)data; | |
113 | unsigned long now = (unsigned long)xtime.tv_sec; | |
114 | long next = LONG_MAX; | |
115 | int warn = 0; | |
116 | ||
117 | spin_lock(&x->lock); | |
118 | if (x->km.state == XFRM_STATE_DEAD) | |
119 | goto out; | |
120 | if (x->km.state == XFRM_STATE_EXPIRED) | |
121 | goto expired; | |
122 | if (x->lft.hard_add_expires_seconds) { | |
123 | long tmo = x->lft.hard_add_expires_seconds + | |
124 | x->curlft.add_time - now; | |
125 | if (tmo <= 0) | |
126 | goto expired; | |
127 | if (tmo < next) | |
128 | next = tmo; | |
129 | } | |
130 | if (x->lft.hard_use_expires_seconds) { | |
131 | long tmo = x->lft.hard_use_expires_seconds + | |
132 | (x->curlft.use_time ? : now) - now; | |
133 | if (tmo <= 0) | |
134 | goto expired; | |
135 | if (tmo < next) | |
136 | next = tmo; | |
137 | } | |
138 | if (x->km.dying) | |
139 | goto resched; | |
140 | if (x->lft.soft_add_expires_seconds) { | |
141 | long tmo = x->lft.soft_add_expires_seconds + | |
142 | x->curlft.add_time - now; | |
143 | if (tmo <= 0) | |
144 | warn = 1; | |
145 | else if (tmo < next) | |
146 | next = tmo; | |
147 | } | |
148 | if (x->lft.soft_use_expires_seconds) { | |
149 | long tmo = x->lft.soft_use_expires_seconds + | |
150 | (x->curlft.use_time ? : now) - now; | |
151 | if (tmo <= 0) | |
152 | warn = 1; | |
153 | else if (tmo < next) | |
154 | next = tmo; | |
155 | } | |
156 | ||
157 | if (warn) | |
158 | km_state_expired(x, 0); | |
159 | resched: | |
160 | if (next != LONG_MAX && | |
161 | !mod_timer(&x->timer, jiffies + make_jiffies(next))) | |
162 | xfrm_state_hold(x); | |
163 | goto out; | |
164 | ||
165 | expired: | |
166 | if (x->km.state == XFRM_STATE_ACQ && x->id.spi == 0) { | |
167 | x->km.state = XFRM_STATE_EXPIRED; | |
168 | wake_up(&km_waitq); | |
169 | next = 2; | |
170 | goto resched; | |
171 | } | |
172 | if (x->id.spi != 0) | |
173 | km_state_expired(x, 1); | |
174 | __xfrm_state_delete(x); | |
175 | ||
176 | out: | |
177 | spin_unlock(&x->lock); | |
178 | xfrm_state_put(x); | |
179 | } | |
180 | ||
181 | struct xfrm_state *xfrm_state_alloc(void) | |
182 | { | |
183 | struct xfrm_state *x; | |
184 | ||
185 | x = kmalloc(sizeof(struct xfrm_state), GFP_ATOMIC); | |
186 | ||
187 | if (x) { | |
188 | memset(x, 0, sizeof(struct xfrm_state)); | |
189 | atomic_set(&x->refcnt, 1); | |
190 | atomic_set(&x->tunnel_users, 0); | |
191 | INIT_LIST_HEAD(&x->bydst); | |
192 | INIT_LIST_HEAD(&x->byspi); | |
193 | init_timer(&x->timer); | |
194 | x->timer.function = xfrm_timer_handler; | |
195 | x->timer.data = (unsigned long)x; | |
196 | x->curlft.add_time = (unsigned long)xtime.tv_sec; | |
197 | x->lft.soft_byte_limit = XFRM_INF; | |
198 | x->lft.soft_packet_limit = XFRM_INF; | |
199 | x->lft.hard_byte_limit = XFRM_INF; | |
200 | x->lft.hard_packet_limit = XFRM_INF; | |
201 | spin_lock_init(&x->lock); | |
202 | } | |
203 | return x; | |
204 | } | |
205 | EXPORT_SYMBOL(xfrm_state_alloc); | |
206 | ||
207 | void __xfrm_state_destroy(struct xfrm_state *x) | |
208 | { | |
209 | BUG_TRAP(x->km.state == XFRM_STATE_DEAD); | |
210 | ||
211 | spin_lock_bh(&xfrm_state_gc_lock); | |
212 | list_add(&x->bydst, &xfrm_state_gc_list); | |
213 | spin_unlock_bh(&xfrm_state_gc_lock); | |
214 | schedule_work(&xfrm_state_gc_work); | |
215 | } | |
216 | EXPORT_SYMBOL(__xfrm_state_destroy); | |
217 | ||
218 | static void __xfrm_state_delete(struct xfrm_state *x) | |
219 | { | |
220 | if (x->km.state != XFRM_STATE_DEAD) { | |
221 | x->km.state = XFRM_STATE_DEAD; | |
222 | spin_lock(&xfrm_state_lock); | |
223 | list_del(&x->bydst); | |
224 | atomic_dec(&x->refcnt); | |
225 | if (x->id.spi) { | |
226 | list_del(&x->byspi); | |
227 | atomic_dec(&x->refcnt); | |
228 | } | |
229 | spin_unlock(&xfrm_state_lock); | |
230 | if (del_timer(&x->timer)) | |
231 | atomic_dec(&x->refcnt); | |
232 | ||
233 | /* The number two in this test is the reference | |
234 | * mentioned in the comment below plus the reference | |
235 | * our caller holds. A larger value means that | |
236 | * there are DSTs attached to this xfrm_state. | |
237 | */ | |
238 | if (atomic_read(&x->refcnt) > 2) { | |
239 | xfrm_state_gc_flush_bundles = 1; | |
240 | schedule_work(&xfrm_state_gc_work); | |
241 | } | |
242 | ||
243 | /* All xfrm_state objects are created by xfrm_state_alloc. | |
244 | * The xfrm_state_alloc call gives a reference, and that | |
245 | * is what we are dropping here. | |
246 | */ | |
247 | atomic_dec(&x->refcnt); | |
248 | } | |
249 | } | |
250 | ||
251 | void xfrm_state_delete(struct xfrm_state *x) | |
252 | { | |
253 | spin_lock_bh(&x->lock); | |
254 | __xfrm_state_delete(x); | |
255 | spin_unlock_bh(&x->lock); | |
256 | } | |
257 | EXPORT_SYMBOL(xfrm_state_delete); | |
258 | ||
259 | void xfrm_state_flush(u8 proto) | |
260 | { | |
261 | int i; | |
262 | struct xfrm_state *x; | |
263 | ||
264 | spin_lock_bh(&xfrm_state_lock); | |
265 | for (i = 0; i < XFRM_DST_HSIZE; i++) { | |
266 | restart: | |
267 | list_for_each_entry(x, xfrm_state_bydst+i, bydst) { | |
268 | if (!xfrm_state_kern(x) && | |
269 | (proto == IPSEC_PROTO_ANY || x->id.proto == proto)) { | |
270 | xfrm_state_hold(x); | |
271 | spin_unlock_bh(&xfrm_state_lock); | |
272 | ||
273 | xfrm_state_delete(x); | |
274 | xfrm_state_put(x); | |
275 | ||
276 | spin_lock_bh(&xfrm_state_lock); | |
277 | goto restart; | |
278 | } | |
279 | } | |
280 | } | |
281 | spin_unlock_bh(&xfrm_state_lock); | |
282 | wake_up(&km_waitq); | |
283 | } | |
284 | EXPORT_SYMBOL(xfrm_state_flush); | |
285 | ||
286 | static int | |
287 | xfrm_init_tempsel(struct xfrm_state *x, struct flowi *fl, | |
288 | struct xfrm_tmpl *tmpl, | |
289 | xfrm_address_t *daddr, xfrm_address_t *saddr, | |
290 | unsigned short family) | |
291 | { | |
292 | struct xfrm_state_afinfo *afinfo = xfrm_state_get_afinfo(family); | |
293 | if (!afinfo) | |
294 | return -1; | |
295 | afinfo->init_tempsel(x, fl, tmpl, daddr, saddr); | |
296 | xfrm_state_put_afinfo(afinfo); | |
297 | return 0; | |
298 | } | |
299 | ||
300 | struct xfrm_state * | |
301 | xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr, | |
302 | struct flowi *fl, struct xfrm_tmpl *tmpl, | |
303 | struct xfrm_policy *pol, int *err, | |
304 | unsigned short family) | |
305 | { | |
306 | unsigned h = xfrm_dst_hash(daddr, family); | |
307 | struct xfrm_state *x, *x0; | |
308 | int acquire_in_progress = 0; | |
309 | int error = 0; | |
310 | struct xfrm_state *best = NULL; | |
311 | struct xfrm_state_afinfo *afinfo; | |
312 | ||
313 | afinfo = xfrm_state_get_afinfo(family); | |
314 | if (afinfo == NULL) { | |
315 | *err = -EAFNOSUPPORT; | |
316 | return NULL; | |
317 | } | |
318 | ||
319 | spin_lock_bh(&xfrm_state_lock); | |
320 | list_for_each_entry(x, xfrm_state_bydst+h, bydst) { | |
321 | if (x->props.family == family && | |
322 | x->props.reqid == tmpl->reqid && | |
323 | xfrm_state_addr_check(x, daddr, saddr, family) && | |
324 | tmpl->mode == x->props.mode && | |
325 | tmpl->id.proto == x->id.proto && | |
326 | (tmpl->id.spi == x->id.spi || !tmpl->id.spi)) { | |
327 | /* Resolution logic: | |
328 | 1. There is a valid state with matching selector. | |
329 | Done. | |
330 | 2. Valid state with inappropriate selector. Skip. | |
331 | ||
332 | Entering area of "sysdeps". | |
333 | ||
334 | 3. If state is not valid, selector is temporary, | |
335 | it selects only session which triggered | |
336 | previous resolution. Key manager will do | |
337 | something to install a state with proper | |
338 | selector. | |
339 | */ | |
340 | if (x->km.state == XFRM_STATE_VALID) { | |
341 | if (!xfrm_selector_match(&x->sel, fl, family)) | |
342 | continue; | |
343 | if (!best || | |
344 | best->km.dying > x->km.dying || | |
345 | (best->km.dying == x->km.dying && | |
346 | best->curlft.add_time < x->curlft.add_time)) | |
347 | best = x; | |
348 | } else if (x->km.state == XFRM_STATE_ACQ) { | |
349 | acquire_in_progress = 1; | |
350 | } else if (x->km.state == XFRM_STATE_ERROR || | |
351 | x->km.state == XFRM_STATE_EXPIRED) { | |
352 | if (xfrm_selector_match(&x->sel, fl, family)) | |
353 | error = -ESRCH; | |
354 | } | |
355 | } | |
356 | } | |
357 | ||
358 | x = best; | |
359 | if (!x && !error && !acquire_in_progress) { | |
5c5d281a PM |
360 | if (tmpl->id.spi && |
361 | (x0 = afinfo->state_lookup(daddr, tmpl->id.spi, | |
362 | tmpl->id.proto)) != NULL) { | |
1da177e4 LT |
363 | xfrm_state_put(x0); |
364 | error = -EEXIST; | |
365 | goto out; | |
366 | } | |
367 | x = xfrm_state_alloc(); | |
368 | if (x == NULL) { | |
369 | error = -ENOMEM; | |
370 | goto out; | |
371 | } | |
372 | /* Initialize temporary selector matching only | |
373 | * to current session. */ | |
374 | xfrm_init_tempsel(x, fl, tmpl, daddr, saddr, family); | |
375 | ||
376 | if (km_query(x, tmpl, pol) == 0) { | |
377 | x->km.state = XFRM_STATE_ACQ; | |
378 | list_add_tail(&x->bydst, xfrm_state_bydst+h); | |
379 | xfrm_state_hold(x); | |
380 | if (x->id.spi) { | |
381 | h = xfrm_spi_hash(&x->id.daddr, x->id.spi, x->id.proto, family); | |
382 | list_add(&x->byspi, xfrm_state_byspi+h); | |
383 | xfrm_state_hold(x); | |
384 | } | |
385 | x->lft.hard_add_expires_seconds = XFRM_ACQ_EXPIRES; | |
386 | xfrm_state_hold(x); | |
387 | x->timer.expires = jiffies + XFRM_ACQ_EXPIRES*HZ; | |
388 | add_timer(&x->timer); | |
389 | } else { | |
390 | x->km.state = XFRM_STATE_DEAD; | |
391 | xfrm_state_put(x); | |
392 | x = NULL; | |
393 | error = -ESRCH; | |
394 | } | |
395 | } | |
396 | out: | |
397 | if (x) | |
398 | xfrm_state_hold(x); | |
399 | else | |
400 | *err = acquire_in_progress ? -EAGAIN : error; | |
401 | spin_unlock_bh(&xfrm_state_lock); | |
402 | xfrm_state_put_afinfo(afinfo); | |
403 | return x; | |
404 | } | |
405 | ||
406 | static void __xfrm_state_insert(struct xfrm_state *x) | |
407 | { | |
408 | unsigned h = xfrm_dst_hash(&x->id.daddr, x->props.family); | |
409 | ||
410 | list_add(&x->bydst, xfrm_state_bydst+h); | |
411 | xfrm_state_hold(x); | |
412 | ||
413 | h = xfrm_spi_hash(&x->id.daddr, x->id.spi, x->id.proto, x->props.family); | |
414 | ||
415 | list_add(&x->byspi, xfrm_state_byspi+h); | |
416 | xfrm_state_hold(x); | |
417 | ||
418 | if (!mod_timer(&x->timer, jiffies + HZ)) | |
419 | xfrm_state_hold(x); | |
420 | ||
421 | wake_up(&km_waitq); | |
422 | } | |
423 | ||
424 | void xfrm_state_insert(struct xfrm_state *x) | |
425 | { | |
426 | spin_lock_bh(&xfrm_state_lock); | |
427 | __xfrm_state_insert(x); | |
428 | spin_unlock_bh(&xfrm_state_lock); | |
429 | } | |
430 | EXPORT_SYMBOL(xfrm_state_insert); | |
431 | ||
432 | static struct xfrm_state *__xfrm_find_acq_byseq(u32 seq); | |
433 | ||
434 | int xfrm_state_add(struct xfrm_state *x) | |
435 | { | |
436 | struct xfrm_state_afinfo *afinfo; | |
437 | struct xfrm_state *x1; | |
438 | int family; | |
439 | int err; | |
440 | ||
441 | family = x->props.family; | |
442 | afinfo = xfrm_state_get_afinfo(family); | |
443 | if (unlikely(afinfo == NULL)) | |
444 | return -EAFNOSUPPORT; | |
445 | ||
446 | spin_lock_bh(&xfrm_state_lock); | |
447 | ||
448 | x1 = afinfo->state_lookup(&x->id.daddr, x->id.spi, x->id.proto); | |
449 | if (x1) { | |
450 | xfrm_state_put(x1); | |
451 | x1 = NULL; | |
452 | err = -EEXIST; | |
453 | goto out; | |
454 | } | |
455 | ||
456 | if (x->km.seq) { | |
457 | x1 = __xfrm_find_acq_byseq(x->km.seq); | |
458 | if (x1 && xfrm_addr_cmp(&x1->id.daddr, &x->id.daddr, family)) { | |
459 | xfrm_state_put(x1); | |
460 | x1 = NULL; | |
461 | } | |
462 | } | |
463 | ||
464 | if (!x1) | |
465 | x1 = afinfo->find_acq( | |
466 | x->props.mode, x->props.reqid, x->id.proto, | |
467 | &x->id.daddr, &x->props.saddr, 0); | |
468 | ||
469 | __xfrm_state_insert(x); | |
470 | err = 0; | |
471 | ||
472 | out: | |
473 | spin_unlock_bh(&xfrm_state_lock); | |
474 | xfrm_state_put_afinfo(afinfo); | |
475 | ||
476 | if (x1) { | |
477 | xfrm_state_delete(x1); | |
478 | xfrm_state_put(x1); | |
479 | } | |
480 | ||
481 | return err; | |
482 | } | |
483 | EXPORT_SYMBOL(xfrm_state_add); | |
484 | ||
485 | int xfrm_state_update(struct xfrm_state *x) | |
486 | { | |
487 | struct xfrm_state_afinfo *afinfo; | |
488 | struct xfrm_state *x1; | |
489 | int err; | |
490 | ||
491 | afinfo = xfrm_state_get_afinfo(x->props.family); | |
492 | if (unlikely(afinfo == NULL)) | |
493 | return -EAFNOSUPPORT; | |
494 | ||
495 | spin_lock_bh(&xfrm_state_lock); | |
496 | x1 = afinfo->state_lookup(&x->id.daddr, x->id.spi, x->id.proto); | |
497 | ||
498 | err = -ESRCH; | |
499 | if (!x1) | |
500 | goto out; | |
501 | ||
502 | if (xfrm_state_kern(x1)) { | |
503 | xfrm_state_put(x1); | |
504 | err = -EEXIST; | |
505 | goto out; | |
506 | } | |
507 | ||
508 | if (x1->km.state == XFRM_STATE_ACQ) { | |
509 | __xfrm_state_insert(x); | |
510 | x = NULL; | |
511 | } | |
512 | err = 0; | |
513 | ||
514 | out: | |
515 | spin_unlock_bh(&xfrm_state_lock); | |
516 | xfrm_state_put_afinfo(afinfo); | |
517 | ||
518 | if (err) | |
519 | return err; | |
520 | ||
521 | if (!x) { | |
522 | xfrm_state_delete(x1); | |
523 | xfrm_state_put(x1); | |
524 | return 0; | |
525 | } | |
526 | ||
527 | err = -EINVAL; | |
528 | spin_lock_bh(&x1->lock); | |
529 | if (likely(x1->km.state == XFRM_STATE_VALID)) { | |
530 | if (x->encap && x1->encap) | |
531 | memcpy(x1->encap, x->encap, sizeof(*x1->encap)); | |
532 | memcpy(&x1->lft, &x->lft, sizeof(x1->lft)); | |
533 | x1->km.dying = 0; | |
534 | ||
535 | if (!mod_timer(&x1->timer, jiffies + HZ)) | |
536 | xfrm_state_hold(x1); | |
537 | if (x1->curlft.use_time) | |
538 | xfrm_state_check_expire(x1); | |
539 | ||
540 | err = 0; | |
541 | } | |
542 | spin_unlock_bh(&x1->lock); | |
543 | ||
544 | xfrm_state_put(x1); | |
545 | ||
546 | return err; | |
547 | } | |
548 | EXPORT_SYMBOL(xfrm_state_update); | |
549 | ||
550 | int xfrm_state_check_expire(struct xfrm_state *x) | |
551 | { | |
552 | if (!x->curlft.use_time) | |
553 | x->curlft.use_time = (unsigned long)xtime.tv_sec; | |
554 | ||
555 | if (x->km.state != XFRM_STATE_VALID) | |
556 | return -EINVAL; | |
557 | ||
558 | if (x->curlft.bytes >= x->lft.hard_byte_limit || | |
559 | x->curlft.packets >= x->lft.hard_packet_limit) { | |
560 | km_state_expired(x, 1); | |
561 | if (!mod_timer(&x->timer, jiffies + XFRM_ACQ_EXPIRES*HZ)) | |
562 | xfrm_state_hold(x); | |
563 | return -EINVAL; | |
564 | } | |
565 | ||
566 | if (!x->km.dying && | |
567 | (x->curlft.bytes >= x->lft.soft_byte_limit || | |
568 | x->curlft.packets >= x->lft.soft_packet_limit)) | |
569 | km_state_expired(x, 0); | |
570 | return 0; | |
571 | } | |
572 | EXPORT_SYMBOL(xfrm_state_check_expire); | |
573 | ||
574 | static int xfrm_state_check_space(struct xfrm_state *x, struct sk_buff *skb) | |
575 | { | |
576 | int nhead = x->props.header_len + LL_RESERVED_SPACE(skb->dst->dev) | |
577 | - skb_headroom(skb); | |
578 | ||
579 | if (nhead > 0) | |
580 | return pskb_expand_head(skb, nhead, 0, GFP_ATOMIC); | |
581 | ||
582 | /* Check tail too... */ | |
583 | return 0; | |
584 | } | |
585 | ||
586 | int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb) | |
587 | { | |
588 | int err = xfrm_state_check_expire(x); | |
589 | if (err < 0) | |
590 | goto err; | |
591 | err = xfrm_state_check_space(x, skb); | |
592 | err: | |
593 | return err; | |
594 | } | |
595 | EXPORT_SYMBOL(xfrm_state_check); | |
596 | ||
597 | struct xfrm_state * | |
598 | xfrm_state_lookup(xfrm_address_t *daddr, u32 spi, u8 proto, | |
599 | unsigned short family) | |
600 | { | |
601 | struct xfrm_state *x; | |
602 | struct xfrm_state_afinfo *afinfo = xfrm_state_get_afinfo(family); | |
603 | if (!afinfo) | |
604 | return NULL; | |
605 | ||
606 | spin_lock_bh(&xfrm_state_lock); | |
607 | x = afinfo->state_lookup(daddr, spi, proto); | |
608 | spin_unlock_bh(&xfrm_state_lock); | |
609 | xfrm_state_put_afinfo(afinfo); | |
610 | return x; | |
611 | } | |
612 | EXPORT_SYMBOL(xfrm_state_lookup); | |
613 | ||
614 | struct xfrm_state * | |
615 | xfrm_find_acq(u8 mode, u32 reqid, u8 proto, | |
616 | xfrm_address_t *daddr, xfrm_address_t *saddr, | |
617 | int create, unsigned short family) | |
618 | { | |
619 | struct xfrm_state *x; | |
620 | struct xfrm_state_afinfo *afinfo = xfrm_state_get_afinfo(family); | |
621 | if (!afinfo) | |
622 | return NULL; | |
623 | ||
624 | spin_lock_bh(&xfrm_state_lock); | |
625 | x = afinfo->find_acq(mode, reqid, proto, daddr, saddr, create); | |
626 | spin_unlock_bh(&xfrm_state_lock); | |
627 | xfrm_state_put_afinfo(afinfo); | |
628 | return x; | |
629 | } | |
630 | EXPORT_SYMBOL(xfrm_find_acq); | |
631 | ||
632 | /* Silly enough, but I'm lazy to build resolution list */ | |
633 | ||
634 | static struct xfrm_state *__xfrm_find_acq_byseq(u32 seq) | |
635 | { | |
636 | int i; | |
637 | struct xfrm_state *x; | |
638 | ||
639 | for (i = 0; i < XFRM_DST_HSIZE; i++) { | |
640 | list_for_each_entry(x, xfrm_state_bydst+i, bydst) { | |
641 | if (x->km.seq == seq && x->km.state == XFRM_STATE_ACQ) { | |
642 | xfrm_state_hold(x); | |
643 | return x; | |
644 | } | |
645 | } | |
646 | } | |
647 | return NULL; | |
648 | } | |
649 | ||
650 | struct xfrm_state *xfrm_find_acq_byseq(u32 seq) | |
651 | { | |
652 | struct xfrm_state *x; | |
653 | ||
654 | spin_lock_bh(&xfrm_state_lock); | |
655 | x = __xfrm_find_acq_byseq(seq); | |
656 | spin_unlock_bh(&xfrm_state_lock); | |
657 | return x; | |
658 | } | |
659 | EXPORT_SYMBOL(xfrm_find_acq_byseq); | |
660 | ||
661 | u32 xfrm_get_acqseq(void) | |
662 | { | |
663 | u32 res; | |
664 | static u32 acqseq; | |
665 | static DEFINE_SPINLOCK(acqseq_lock); | |
666 | ||
667 | spin_lock_bh(&acqseq_lock); | |
668 | res = (++acqseq ? : ++acqseq); | |
669 | spin_unlock_bh(&acqseq_lock); | |
670 | return res; | |
671 | } | |
672 | EXPORT_SYMBOL(xfrm_get_acqseq); | |
673 | ||
674 | void | |
675 | xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi) | |
676 | { | |
677 | u32 h; | |
678 | struct xfrm_state *x0; | |
679 | ||
680 | if (x->id.spi) | |
681 | return; | |
682 | ||
683 | if (minspi == maxspi) { | |
684 | x0 = xfrm_state_lookup(&x->id.daddr, minspi, x->id.proto, x->props.family); | |
685 | if (x0) { | |
686 | xfrm_state_put(x0); | |
687 | return; | |
688 | } | |
689 | x->id.spi = minspi; | |
690 | } else { | |
691 | u32 spi = 0; | |
692 | minspi = ntohl(minspi); | |
693 | maxspi = ntohl(maxspi); | |
694 | for (h=0; h<maxspi-minspi+1; h++) { | |
695 | spi = minspi + net_random()%(maxspi-minspi+1); | |
696 | x0 = xfrm_state_lookup(&x->id.daddr, htonl(spi), x->id.proto, x->props.family); | |
697 | if (x0 == NULL) { | |
698 | x->id.spi = htonl(spi); | |
699 | break; | |
700 | } | |
701 | xfrm_state_put(x0); | |
702 | } | |
703 | } | |
704 | if (x->id.spi) { | |
705 | spin_lock_bh(&xfrm_state_lock); | |
706 | h = xfrm_spi_hash(&x->id.daddr, x->id.spi, x->id.proto, x->props.family); | |
707 | list_add(&x->byspi, xfrm_state_byspi+h); | |
708 | xfrm_state_hold(x); | |
709 | spin_unlock_bh(&xfrm_state_lock); | |
710 | wake_up(&km_waitq); | |
711 | } | |
712 | } | |
713 | EXPORT_SYMBOL(xfrm_alloc_spi); | |
714 | ||
715 | int xfrm_state_walk(u8 proto, int (*func)(struct xfrm_state *, int, void*), | |
716 | void *data) | |
717 | { | |
718 | int i; | |
719 | struct xfrm_state *x; | |
720 | int count = 0; | |
721 | int err = 0; | |
722 | ||
723 | spin_lock_bh(&xfrm_state_lock); | |
724 | for (i = 0; i < XFRM_DST_HSIZE; i++) { | |
725 | list_for_each_entry(x, xfrm_state_bydst+i, bydst) { | |
726 | if (proto == IPSEC_PROTO_ANY || x->id.proto == proto) | |
727 | count++; | |
728 | } | |
729 | } | |
730 | if (count == 0) { | |
731 | err = -ENOENT; | |
732 | goto out; | |
733 | } | |
734 | ||
735 | for (i = 0; i < XFRM_DST_HSIZE; i++) { | |
736 | list_for_each_entry(x, xfrm_state_bydst+i, bydst) { | |
737 | if (proto != IPSEC_PROTO_ANY && x->id.proto != proto) | |
738 | continue; | |
739 | err = func(x, --count, data); | |
740 | if (err) | |
741 | goto out; | |
742 | } | |
743 | } | |
744 | out: | |
745 | spin_unlock_bh(&xfrm_state_lock); | |
746 | return err; | |
747 | } | |
748 | EXPORT_SYMBOL(xfrm_state_walk); | |
749 | ||
750 | int xfrm_replay_check(struct xfrm_state *x, u32 seq) | |
751 | { | |
752 | u32 diff; | |
753 | ||
754 | seq = ntohl(seq); | |
755 | ||
756 | if (unlikely(seq == 0)) | |
757 | return -EINVAL; | |
758 | ||
759 | if (likely(seq > x->replay.seq)) | |
760 | return 0; | |
761 | ||
762 | diff = x->replay.seq - seq; | |
763 | if (diff >= x->props.replay_window) { | |
764 | x->stats.replay_window++; | |
765 | return -EINVAL; | |
766 | } | |
767 | ||
768 | if (x->replay.bitmap & (1U << diff)) { | |
769 | x->stats.replay++; | |
770 | return -EINVAL; | |
771 | } | |
772 | return 0; | |
773 | } | |
774 | EXPORT_SYMBOL(xfrm_replay_check); | |
775 | ||
776 | void xfrm_replay_advance(struct xfrm_state *x, u32 seq) | |
777 | { | |
778 | u32 diff; | |
779 | ||
780 | seq = ntohl(seq); | |
781 | ||
782 | if (seq > x->replay.seq) { | |
783 | diff = seq - x->replay.seq; | |
784 | if (diff < x->props.replay_window) | |
785 | x->replay.bitmap = ((x->replay.bitmap) << diff) | 1; | |
786 | else | |
787 | x->replay.bitmap = 1; | |
788 | x->replay.seq = seq; | |
789 | } else { | |
790 | diff = x->replay.seq - seq; | |
791 | x->replay.bitmap |= (1U << diff); | |
792 | } | |
793 | } | |
794 | EXPORT_SYMBOL(xfrm_replay_advance); | |
795 | ||
796 | static struct list_head xfrm_km_list = LIST_HEAD_INIT(xfrm_km_list); | |
797 | static DEFINE_RWLOCK(xfrm_km_lock); | |
798 | ||
799 | static void km_state_expired(struct xfrm_state *x, int hard) | |
800 | { | |
801 | struct xfrm_mgr *km; | |
802 | ||
803 | if (hard) | |
804 | x->km.state = XFRM_STATE_EXPIRED; | |
805 | else | |
806 | x->km.dying = 1; | |
807 | ||
808 | read_lock(&xfrm_km_lock); | |
809 | list_for_each_entry(km, &xfrm_km_list, list) | |
810 | km->notify(x, hard); | |
811 | read_unlock(&xfrm_km_lock); | |
812 | ||
813 | if (hard) | |
814 | wake_up(&km_waitq); | |
815 | } | |
816 | ||
817 | static int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol) | |
818 | { | |
819 | int err = -EINVAL; | |
820 | struct xfrm_mgr *km; | |
821 | ||
822 | read_lock(&xfrm_km_lock); | |
823 | list_for_each_entry(km, &xfrm_km_list, list) { | |
824 | err = km->acquire(x, t, pol, XFRM_POLICY_OUT); | |
825 | if (!err) | |
826 | break; | |
827 | } | |
828 | read_unlock(&xfrm_km_lock); | |
829 | return err; | |
830 | } | |
831 | ||
832 | int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport) | |
833 | { | |
834 | int err = -EINVAL; | |
835 | struct xfrm_mgr *km; | |
836 | ||
837 | read_lock(&xfrm_km_lock); | |
838 | list_for_each_entry(km, &xfrm_km_list, list) { | |
839 | if (km->new_mapping) | |
840 | err = km->new_mapping(x, ipaddr, sport); | |
841 | if (!err) | |
842 | break; | |
843 | } | |
844 | read_unlock(&xfrm_km_lock); | |
845 | return err; | |
846 | } | |
847 | EXPORT_SYMBOL(km_new_mapping); | |
848 | ||
849 | void km_policy_expired(struct xfrm_policy *pol, int dir, int hard) | |
850 | { | |
851 | struct xfrm_mgr *km; | |
852 | ||
853 | read_lock(&xfrm_km_lock); | |
854 | list_for_each_entry(km, &xfrm_km_list, list) | |
855 | if (km->notify_policy) | |
856 | km->notify_policy(pol, dir, hard); | |
857 | read_unlock(&xfrm_km_lock); | |
858 | ||
859 | if (hard) | |
860 | wake_up(&km_waitq); | |
861 | } | |
862 | ||
863 | int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen) | |
864 | { | |
865 | int err; | |
866 | u8 *data; | |
867 | struct xfrm_mgr *km; | |
868 | struct xfrm_policy *pol = NULL; | |
869 | ||
870 | if (optlen <= 0 || optlen > PAGE_SIZE) | |
871 | return -EMSGSIZE; | |
872 | ||
873 | data = kmalloc(optlen, GFP_KERNEL); | |
874 | if (!data) | |
875 | return -ENOMEM; | |
876 | ||
877 | err = -EFAULT; | |
878 | if (copy_from_user(data, optval, optlen)) | |
879 | goto out; | |
880 | ||
881 | err = -EINVAL; | |
882 | read_lock(&xfrm_km_lock); | |
883 | list_for_each_entry(km, &xfrm_km_list, list) { | |
884 | pol = km->compile_policy(sk->sk_family, optname, data, | |
885 | optlen, &err); | |
886 | if (err >= 0) | |
887 | break; | |
888 | } | |
889 | read_unlock(&xfrm_km_lock); | |
890 | ||
891 | if (err >= 0) { | |
892 | xfrm_sk_policy_insert(sk, err, pol); | |
893 | xfrm_pol_put(pol); | |
894 | err = 0; | |
895 | } | |
896 | ||
897 | out: | |
898 | kfree(data); | |
899 | return err; | |
900 | } | |
901 | EXPORT_SYMBOL(xfrm_user_policy); | |
902 | ||
903 | int xfrm_register_km(struct xfrm_mgr *km) | |
904 | { | |
905 | write_lock_bh(&xfrm_km_lock); | |
906 | list_add_tail(&km->list, &xfrm_km_list); | |
907 | write_unlock_bh(&xfrm_km_lock); | |
908 | return 0; | |
909 | } | |
910 | EXPORT_SYMBOL(xfrm_register_km); | |
911 | ||
912 | int xfrm_unregister_km(struct xfrm_mgr *km) | |
913 | { | |
914 | write_lock_bh(&xfrm_km_lock); | |
915 | list_del(&km->list); | |
916 | write_unlock_bh(&xfrm_km_lock); | |
917 | return 0; | |
918 | } | |
919 | EXPORT_SYMBOL(xfrm_unregister_km); | |
920 | ||
921 | int xfrm_state_register_afinfo(struct xfrm_state_afinfo *afinfo) | |
922 | { | |
923 | int err = 0; | |
924 | if (unlikely(afinfo == NULL)) | |
925 | return -EINVAL; | |
926 | if (unlikely(afinfo->family >= NPROTO)) | |
927 | return -EAFNOSUPPORT; | |
928 | write_lock(&xfrm_state_afinfo_lock); | |
929 | if (unlikely(xfrm_state_afinfo[afinfo->family] != NULL)) | |
930 | err = -ENOBUFS; | |
931 | else { | |
932 | afinfo->state_bydst = xfrm_state_bydst; | |
933 | afinfo->state_byspi = xfrm_state_byspi; | |
934 | xfrm_state_afinfo[afinfo->family] = afinfo; | |
935 | } | |
936 | write_unlock(&xfrm_state_afinfo_lock); | |
937 | return err; | |
938 | } | |
939 | EXPORT_SYMBOL(xfrm_state_register_afinfo); | |
940 | ||
941 | int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo) | |
942 | { | |
943 | int err = 0; | |
944 | if (unlikely(afinfo == NULL)) | |
945 | return -EINVAL; | |
946 | if (unlikely(afinfo->family >= NPROTO)) | |
947 | return -EAFNOSUPPORT; | |
948 | write_lock(&xfrm_state_afinfo_lock); | |
949 | if (likely(xfrm_state_afinfo[afinfo->family] != NULL)) { | |
950 | if (unlikely(xfrm_state_afinfo[afinfo->family] != afinfo)) | |
951 | err = -EINVAL; | |
952 | else { | |
953 | xfrm_state_afinfo[afinfo->family] = NULL; | |
954 | afinfo->state_byspi = NULL; | |
955 | afinfo->state_bydst = NULL; | |
956 | } | |
957 | } | |
958 | write_unlock(&xfrm_state_afinfo_lock); | |
959 | return err; | |
960 | } | |
961 | EXPORT_SYMBOL(xfrm_state_unregister_afinfo); | |
962 | ||
963 | static struct xfrm_state_afinfo *xfrm_state_get_afinfo(unsigned short family) | |
964 | { | |
965 | struct xfrm_state_afinfo *afinfo; | |
966 | if (unlikely(family >= NPROTO)) | |
967 | return NULL; | |
968 | read_lock(&xfrm_state_afinfo_lock); | |
969 | afinfo = xfrm_state_afinfo[family]; | |
970 | if (likely(afinfo != NULL)) | |
971 | read_lock(&afinfo->lock); | |
972 | read_unlock(&xfrm_state_afinfo_lock); | |
973 | return afinfo; | |
974 | } | |
975 | ||
976 | static void xfrm_state_put_afinfo(struct xfrm_state_afinfo *afinfo) | |
977 | { | |
978 | if (unlikely(afinfo == NULL)) | |
979 | return; | |
980 | read_unlock(&afinfo->lock); | |
981 | } | |
982 | ||
983 | /* Temporarily located here until net/xfrm/xfrm_tunnel.c is created */ | |
984 | void xfrm_state_delete_tunnel(struct xfrm_state *x) | |
985 | { | |
986 | if (x->tunnel) { | |
987 | struct xfrm_state *t = x->tunnel; | |
988 | ||
989 | if (atomic_read(&t->tunnel_users) == 2) | |
990 | xfrm_state_delete(t); | |
991 | atomic_dec(&t->tunnel_users); | |
992 | xfrm_state_put(t); | |
993 | x->tunnel = NULL; | |
994 | } | |
995 | } | |
996 | EXPORT_SYMBOL(xfrm_state_delete_tunnel); | |
997 | ||
998 | int xfrm_state_mtu(struct xfrm_state *x, int mtu) | |
999 | { | |
1000 | int res = mtu; | |
1001 | ||
1002 | res -= x->props.header_len; | |
1003 | ||
1004 | for (;;) { | |
1005 | int m = res; | |
1006 | ||
1007 | if (m < 68) | |
1008 | return 68; | |
1009 | ||
1010 | spin_lock_bh(&x->lock); | |
1011 | if (x->km.state == XFRM_STATE_VALID && | |
1012 | x->type && x->type->get_max_size) | |
1013 | m = x->type->get_max_size(x, m); | |
1014 | else | |
1015 | m += x->props.header_len; | |
1016 | spin_unlock_bh(&x->lock); | |
1017 | ||
1018 | if (m <= mtu) | |
1019 | break; | |
1020 | res -= (m - mtu); | |
1021 | } | |
1022 | ||
1023 | return res; | |
1024 | } | |
1025 | ||
1026 | EXPORT_SYMBOL(xfrm_state_mtu); | |
1027 | ||
1028 | void __init xfrm_state_init(void) | |
1029 | { | |
1030 | int i; | |
1031 | ||
1032 | for (i=0; i<XFRM_DST_HSIZE; i++) { | |
1033 | INIT_LIST_HEAD(&xfrm_state_bydst[i]); | |
1034 | INIT_LIST_HEAD(&xfrm_state_byspi[i]); | |
1035 | } | |
1036 | INIT_WORK(&xfrm_state_gc_work, xfrm_state_gc_task, NULL); | |
1037 | } | |
1038 |