Commit | Line | Data |
---|---|---|
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) { | |
360 | x0 = afinfo->state_lookup(&tmpl->id.daddr, tmpl->id.spi, tmpl->id.proto); | |
361 | if (x0 != NULL) { | |
362 | xfrm_state_put(x0); | |
363 | error = -EEXIST; | |
364 | goto out; | |
365 | } | |
366 | x = xfrm_state_alloc(); | |
367 | if (x == NULL) { | |
368 | error = -ENOMEM; | |
369 | goto out; | |
370 | } | |
371 | /* Initialize temporary selector matching only | |
372 | * to current session. */ | |
373 | xfrm_init_tempsel(x, fl, tmpl, daddr, saddr, family); | |
374 | ||
375 | if (km_query(x, tmpl, pol) == 0) { | |
376 | x->km.state = XFRM_STATE_ACQ; | |
377 | list_add_tail(&x->bydst, xfrm_state_bydst+h); | |
378 | xfrm_state_hold(x); | |
379 | if (x->id.spi) { | |
380 | h = xfrm_spi_hash(&x->id.daddr, x->id.spi, x->id.proto, family); | |
381 | list_add(&x->byspi, xfrm_state_byspi+h); | |
382 | xfrm_state_hold(x); | |
383 | } | |
384 | x->lft.hard_add_expires_seconds = XFRM_ACQ_EXPIRES; | |
385 | xfrm_state_hold(x); | |
386 | x->timer.expires = jiffies + XFRM_ACQ_EXPIRES*HZ; | |
387 | add_timer(&x->timer); | |
388 | } else { | |
389 | x->km.state = XFRM_STATE_DEAD; | |
390 | xfrm_state_put(x); | |
391 | x = NULL; | |
392 | error = -ESRCH; | |
393 | } | |
394 | } | |
395 | out: | |
396 | if (x) | |
397 | xfrm_state_hold(x); | |
398 | else | |
399 | *err = acquire_in_progress ? -EAGAIN : error; | |
400 | spin_unlock_bh(&xfrm_state_lock); | |
401 | xfrm_state_put_afinfo(afinfo); | |
402 | return x; | |
403 | } | |
404 | ||
405 | static void __xfrm_state_insert(struct xfrm_state *x) | |
406 | { | |
407 | unsigned h = xfrm_dst_hash(&x->id.daddr, x->props.family); | |
408 | ||
409 | list_add(&x->bydst, xfrm_state_bydst+h); | |
410 | xfrm_state_hold(x); | |
411 | ||
412 | h = xfrm_spi_hash(&x->id.daddr, x->id.spi, x->id.proto, x->props.family); | |
413 | ||
414 | list_add(&x->byspi, xfrm_state_byspi+h); | |
415 | xfrm_state_hold(x); | |
416 | ||
417 | if (!mod_timer(&x->timer, jiffies + HZ)) | |
418 | xfrm_state_hold(x); | |
419 | ||
420 | wake_up(&km_waitq); | |
421 | } | |
422 | ||
423 | void xfrm_state_insert(struct xfrm_state *x) | |
424 | { | |
425 | spin_lock_bh(&xfrm_state_lock); | |
426 | __xfrm_state_insert(x); | |
427 | spin_unlock_bh(&xfrm_state_lock); | |
428 | } | |
429 | EXPORT_SYMBOL(xfrm_state_insert); | |
430 | ||
431 | static struct xfrm_state *__xfrm_find_acq_byseq(u32 seq); | |
432 | ||
433 | int xfrm_state_add(struct xfrm_state *x) | |
434 | { | |
435 | struct xfrm_state_afinfo *afinfo; | |
436 | struct xfrm_state *x1; | |
437 | int family; | |
438 | int err; | |
439 | ||
440 | family = x->props.family; | |
441 | afinfo = xfrm_state_get_afinfo(family); | |
442 | if (unlikely(afinfo == NULL)) | |
443 | return -EAFNOSUPPORT; | |
444 | ||
445 | spin_lock_bh(&xfrm_state_lock); | |
446 | ||
447 | x1 = afinfo->state_lookup(&x->id.daddr, x->id.spi, x->id.proto); | |
448 | if (x1) { | |
449 | xfrm_state_put(x1); | |
450 | x1 = NULL; | |
451 | err = -EEXIST; | |
452 | goto out; | |
453 | } | |
454 | ||
455 | if (x->km.seq) { | |
456 | x1 = __xfrm_find_acq_byseq(x->km.seq); | |
457 | if (x1 && xfrm_addr_cmp(&x1->id.daddr, &x->id.daddr, family)) { | |
458 | xfrm_state_put(x1); | |
459 | x1 = NULL; | |
460 | } | |
461 | } | |
462 | ||
463 | if (!x1) | |
464 | x1 = afinfo->find_acq( | |
465 | x->props.mode, x->props.reqid, x->id.proto, | |
466 | &x->id.daddr, &x->props.saddr, 0); | |
467 | ||
468 | __xfrm_state_insert(x); | |
469 | err = 0; | |
470 | ||
471 | out: | |
472 | spin_unlock_bh(&xfrm_state_lock); | |
473 | xfrm_state_put_afinfo(afinfo); | |
474 | ||
475 | if (x1) { | |
476 | xfrm_state_delete(x1); | |
477 | xfrm_state_put(x1); | |
478 | } | |
479 | ||
480 | return err; | |
481 | } | |
482 | EXPORT_SYMBOL(xfrm_state_add); | |
483 | ||
484 | int xfrm_state_update(struct xfrm_state *x) | |
485 | { | |
486 | struct xfrm_state_afinfo *afinfo; | |
487 | struct xfrm_state *x1; | |
488 | int err; | |
489 | ||
490 | afinfo = xfrm_state_get_afinfo(x->props.family); | |
491 | if (unlikely(afinfo == NULL)) | |
492 | return -EAFNOSUPPORT; | |
493 | ||
494 | spin_lock_bh(&xfrm_state_lock); | |
495 | x1 = afinfo->state_lookup(&x->id.daddr, x->id.spi, x->id.proto); | |
496 | ||
497 | err = -ESRCH; | |
498 | if (!x1) | |
499 | goto out; | |
500 | ||
501 | if (xfrm_state_kern(x1)) { | |
502 | xfrm_state_put(x1); | |
503 | err = -EEXIST; | |
504 | goto out; | |
505 | } | |
506 | ||
507 | if (x1->km.state == XFRM_STATE_ACQ) { | |
508 | __xfrm_state_insert(x); | |
509 | x = NULL; | |
510 | } | |
511 | err = 0; | |
512 | ||
513 | out: | |
514 | spin_unlock_bh(&xfrm_state_lock); | |
515 | xfrm_state_put_afinfo(afinfo); | |
516 | ||
517 | if (err) | |
518 | return err; | |
519 | ||
520 | if (!x) { | |
521 | xfrm_state_delete(x1); | |
522 | xfrm_state_put(x1); | |
523 | return 0; | |
524 | } | |
525 | ||
526 | err = -EINVAL; | |
527 | spin_lock_bh(&x1->lock); | |
528 | if (likely(x1->km.state == XFRM_STATE_VALID)) { | |
529 | if (x->encap && x1->encap) | |
530 | memcpy(x1->encap, x->encap, sizeof(*x1->encap)); | |
531 | memcpy(&x1->lft, &x->lft, sizeof(x1->lft)); | |
532 | x1->km.dying = 0; | |
533 | ||
534 | if (!mod_timer(&x1->timer, jiffies + HZ)) | |
535 | xfrm_state_hold(x1); | |
536 | if (x1->curlft.use_time) | |
537 | xfrm_state_check_expire(x1); | |
538 | ||
539 | err = 0; | |
540 | } | |
541 | spin_unlock_bh(&x1->lock); | |
542 | ||
543 | xfrm_state_put(x1); | |
544 | ||
545 | return err; | |
546 | } | |
547 | EXPORT_SYMBOL(xfrm_state_update); | |
548 | ||
549 | int xfrm_state_check_expire(struct xfrm_state *x) | |
550 | { | |
551 | if (!x->curlft.use_time) | |
552 | x->curlft.use_time = (unsigned long)xtime.tv_sec; | |
553 | ||
554 | if (x->km.state != XFRM_STATE_VALID) | |
555 | return -EINVAL; | |
556 | ||
557 | if (x->curlft.bytes >= x->lft.hard_byte_limit || | |
558 | x->curlft.packets >= x->lft.hard_packet_limit) { | |
559 | km_state_expired(x, 1); | |
560 | if (!mod_timer(&x->timer, jiffies + XFRM_ACQ_EXPIRES*HZ)) | |
561 | xfrm_state_hold(x); | |
562 | return -EINVAL; | |
563 | } | |
564 | ||
565 | if (!x->km.dying && | |
566 | (x->curlft.bytes >= x->lft.soft_byte_limit || | |
567 | x->curlft.packets >= x->lft.soft_packet_limit)) | |
568 | km_state_expired(x, 0); | |
569 | return 0; | |
570 | } | |
571 | EXPORT_SYMBOL(xfrm_state_check_expire); | |
572 | ||
573 | static int xfrm_state_check_space(struct xfrm_state *x, struct sk_buff *skb) | |
574 | { | |
575 | int nhead = x->props.header_len + LL_RESERVED_SPACE(skb->dst->dev) | |
576 | - skb_headroom(skb); | |
577 | ||
578 | if (nhead > 0) | |
579 | return pskb_expand_head(skb, nhead, 0, GFP_ATOMIC); | |
580 | ||
581 | /* Check tail too... */ | |
582 | return 0; | |
583 | } | |
584 | ||
585 | int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb) | |
586 | { | |
587 | int err = xfrm_state_check_expire(x); | |
588 | if (err < 0) | |
589 | goto err; | |
590 | err = xfrm_state_check_space(x, skb); | |
591 | err: | |
592 | return err; | |
593 | } | |
594 | EXPORT_SYMBOL(xfrm_state_check); | |
595 | ||
596 | struct xfrm_state * | |
597 | xfrm_state_lookup(xfrm_address_t *daddr, u32 spi, u8 proto, | |
598 | unsigned short family) | |
599 | { | |
600 | struct xfrm_state *x; | |
601 | struct xfrm_state_afinfo *afinfo = xfrm_state_get_afinfo(family); | |
602 | if (!afinfo) | |
603 | return NULL; | |
604 | ||
605 | spin_lock_bh(&xfrm_state_lock); | |
606 | x = afinfo->state_lookup(daddr, spi, proto); | |
607 | spin_unlock_bh(&xfrm_state_lock); | |
608 | xfrm_state_put_afinfo(afinfo); | |
609 | return x; | |
610 | } | |
611 | EXPORT_SYMBOL(xfrm_state_lookup); | |
612 | ||
613 | struct xfrm_state * | |
614 | xfrm_find_acq(u8 mode, u32 reqid, u8 proto, | |
615 | xfrm_address_t *daddr, xfrm_address_t *saddr, | |
616 | int create, unsigned short family) | |
617 | { | |
618 | struct xfrm_state *x; | |
619 | struct xfrm_state_afinfo *afinfo = xfrm_state_get_afinfo(family); | |
620 | if (!afinfo) | |
621 | return NULL; | |
622 | ||
623 | spin_lock_bh(&xfrm_state_lock); | |
624 | x = afinfo->find_acq(mode, reqid, proto, daddr, saddr, create); | |
625 | spin_unlock_bh(&xfrm_state_lock); | |
626 | xfrm_state_put_afinfo(afinfo); | |
627 | return x; | |
628 | } | |
629 | EXPORT_SYMBOL(xfrm_find_acq); | |
630 | ||
631 | /* Silly enough, but I'm lazy to build resolution list */ | |
632 | ||
633 | static struct xfrm_state *__xfrm_find_acq_byseq(u32 seq) | |
634 | { | |
635 | int i; | |
636 | struct xfrm_state *x; | |
637 | ||
638 | for (i = 0; i < XFRM_DST_HSIZE; i++) { | |
639 | list_for_each_entry(x, xfrm_state_bydst+i, bydst) { | |
640 | if (x->km.seq == seq && x->km.state == XFRM_STATE_ACQ) { | |
641 | xfrm_state_hold(x); | |
642 | return x; | |
643 | } | |
644 | } | |
645 | } | |
646 | return NULL; | |
647 | } | |
648 | ||
649 | struct xfrm_state *xfrm_find_acq_byseq(u32 seq) | |
650 | { | |
651 | struct xfrm_state *x; | |
652 | ||
653 | spin_lock_bh(&xfrm_state_lock); | |
654 | x = __xfrm_find_acq_byseq(seq); | |
655 | spin_unlock_bh(&xfrm_state_lock); | |
656 | return x; | |
657 | } | |
658 | EXPORT_SYMBOL(xfrm_find_acq_byseq); | |
659 | ||
660 | u32 xfrm_get_acqseq(void) | |
661 | { | |
662 | u32 res; | |
663 | static u32 acqseq; | |
664 | static DEFINE_SPINLOCK(acqseq_lock); | |
665 | ||
666 | spin_lock_bh(&acqseq_lock); | |
667 | res = (++acqseq ? : ++acqseq); | |
668 | spin_unlock_bh(&acqseq_lock); | |
669 | return res; | |
670 | } | |
671 | EXPORT_SYMBOL(xfrm_get_acqseq); | |
672 | ||
673 | void | |
674 | xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi) | |
675 | { | |
676 | u32 h; | |
677 | struct xfrm_state *x0; | |
678 | ||
679 | if (x->id.spi) | |
680 | return; | |
681 | ||
682 | if (minspi == maxspi) { | |
683 | x0 = xfrm_state_lookup(&x->id.daddr, minspi, x->id.proto, x->props.family); | |
684 | if (x0) { | |
685 | xfrm_state_put(x0); | |
686 | return; | |
687 | } | |
688 | x->id.spi = minspi; | |
689 | } else { | |
690 | u32 spi = 0; | |
691 | minspi = ntohl(minspi); | |
692 | maxspi = ntohl(maxspi); | |
693 | for (h=0; h<maxspi-minspi+1; h++) { | |
694 | spi = minspi + net_random()%(maxspi-minspi+1); | |
695 | x0 = xfrm_state_lookup(&x->id.daddr, htonl(spi), x->id.proto, x->props.family); | |
696 | if (x0 == NULL) { | |
697 | x->id.spi = htonl(spi); | |
698 | break; | |
699 | } | |
700 | xfrm_state_put(x0); | |
701 | } | |
702 | } | |
703 | if (x->id.spi) { | |
704 | spin_lock_bh(&xfrm_state_lock); | |
705 | h = xfrm_spi_hash(&x->id.daddr, x->id.spi, x->id.proto, x->props.family); | |
706 | list_add(&x->byspi, xfrm_state_byspi+h); | |
707 | xfrm_state_hold(x); | |
708 | spin_unlock_bh(&xfrm_state_lock); | |
709 | wake_up(&km_waitq); | |
710 | } | |
711 | } | |
712 | EXPORT_SYMBOL(xfrm_alloc_spi); | |
713 | ||
714 | int xfrm_state_walk(u8 proto, int (*func)(struct xfrm_state *, int, void*), | |
715 | void *data) | |
716 | { | |
717 | int i; | |
718 | struct xfrm_state *x; | |
719 | int count = 0; | |
720 | int err = 0; | |
721 | ||
722 | spin_lock_bh(&xfrm_state_lock); | |
723 | for (i = 0; i < XFRM_DST_HSIZE; i++) { | |
724 | list_for_each_entry(x, xfrm_state_bydst+i, bydst) { | |
725 | if (proto == IPSEC_PROTO_ANY || x->id.proto == proto) | |
726 | count++; | |
727 | } | |
728 | } | |
729 | if (count == 0) { | |
730 | err = -ENOENT; | |
731 | goto out; | |
732 | } | |
733 | ||
734 | for (i = 0; i < XFRM_DST_HSIZE; i++) { | |
735 | list_for_each_entry(x, xfrm_state_bydst+i, bydst) { | |
736 | if (proto != IPSEC_PROTO_ANY && x->id.proto != proto) | |
737 | continue; | |
738 | err = func(x, --count, data); | |
739 | if (err) | |
740 | goto out; | |
741 | } | |
742 | } | |
743 | out: | |
744 | spin_unlock_bh(&xfrm_state_lock); | |
745 | return err; | |
746 | } | |
747 | EXPORT_SYMBOL(xfrm_state_walk); | |
748 | ||
749 | int xfrm_replay_check(struct xfrm_state *x, u32 seq) | |
750 | { | |
751 | u32 diff; | |
752 | ||
753 | seq = ntohl(seq); | |
754 | ||
755 | if (unlikely(seq == 0)) | |
756 | return -EINVAL; | |
757 | ||
758 | if (likely(seq > x->replay.seq)) | |
759 | return 0; | |
760 | ||
761 | diff = x->replay.seq - seq; | |
762 | if (diff >= x->props.replay_window) { | |
763 | x->stats.replay_window++; | |
764 | return -EINVAL; | |
765 | } | |
766 | ||
767 | if (x->replay.bitmap & (1U << diff)) { | |
768 | x->stats.replay++; | |
769 | return -EINVAL; | |
770 | } | |
771 | return 0; | |
772 | } | |
773 | EXPORT_SYMBOL(xfrm_replay_check); | |
774 | ||
775 | void xfrm_replay_advance(struct xfrm_state *x, u32 seq) | |
776 | { | |
777 | u32 diff; | |
778 | ||
779 | seq = ntohl(seq); | |
780 | ||
781 | if (seq > x->replay.seq) { | |
782 | diff = seq - x->replay.seq; | |
783 | if (diff < x->props.replay_window) | |
784 | x->replay.bitmap = ((x->replay.bitmap) << diff) | 1; | |
785 | else | |
786 | x->replay.bitmap = 1; | |
787 | x->replay.seq = seq; | |
788 | } else { | |
789 | diff = x->replay.seq - seq; | |
790 | x->replay.bitmap |= (1U << diff); | |
791 | } | |
792 | } | |
793 | EXPORT_SYMBOL(xfrm_replay_advance); | |
794 | ||
795 | static struct list_head xfrm_km_list = LIST_HEAD_INIT(xfrm_km_list); | |
796 | static DEFINE_RWLOCK(xfrm_km_lock); | |
797 | ||
798 | static void km_state_expired(struct xfrm_state *x, int hard) | |
799 | { | |
800 | struct xfrm_mgr *km; | |
801 | ||
802 | if (hard) | |
803 | x->km.state = XFRM_STATE_EXPIRED; | |
804 | else | |
805 | x->km.dying = 1; | |
806 | ||
807 | read_lock(&xfrm_km_lock); | |
808 | list_for_each_entry(km, &xfrm_km_list, list) | |
809 | km->notify(x, hard); | |
810 | read_unlock(&xfrm_km_lock); | |
811 | ||
812 | if (hard) | |
813 | wake_up(&km_waitq); | |
814 | } | |
815 | ||
816 | static int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol) | |
817 | { | |
818 | int err = -EINVAL; | |
819 | struct xfrm_mgr *km; | |
820 | ||
821 | read_lock(&xfrm_km_lock); | |
822 | list_for_each_entry(km, &xfrm_km_list, list) { | |
823 | err = km->acquire(x, t, pol, XFRM_POLICY_OUT); | |
824 | if (!err) | |
825 | break; | |
826 | } | |
827 | read_unlock(&xfrm_km_lock); | |
828 | return err; | |
829 | } | |
830 | ||
831 | int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport) | |
832 | { | |
833 | int err = -EINVAL; | |
834 | struct xfrm_mgr *km; | |
835 | ||
836 | read_lock(&xfrm_km_lock); | |
837 | list_for_each_entry(km, &xfrm_km_list, list) { | |
838 | if (km->new_mapping) | |
839 | err = km->new_mapping(x, ipaddr, sport); | |
840 | if (!err) | |
841 | break; | |
842 | } | |
843 | read_unlock(&xfrm_km_lock); | |
844 | return err; | |
845 | } | |
846 | EXPORT_SYMBOL(km_new_mapping); | |
847 | ||
848 | void km_policy_expired(struct xfrm_policy *pol, int dir, int hard) | |
849 | { | |
850 | struct xfrm_mgr *km; | |
851 | ||
852 | read_lock(&xfrm_km_lock); | |
853 | list_for_each_entry(km, &xfrm_km_list, list) | |
854 | if (km->notify_policy) | |
855 | km->notify_policy(pol, dir, hard); | |
856 | read_unlock(&xfrm_km_lock); | |
857 | ||
858 | if (hard) | |
859 | wake_up(&km_waitq); | |
860 | } | |
861 | ||
862 | int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen) | |
863 | { | |
864 | int err; | |
865 | u8 *data; | |
866 | struct xfrm_mgr *km; | |
867 | struct xfrm_policy *pol = NULL; | |
868 | ||
869 | if (optlen <= 0 || optlen > PAGE_SIZE) | |
870 | return -EMSGSIZE; | |
871 | ||
872 | data = kmalloc(optlen, GFP_KERNEL); | |
873 | if (!data) | |
874 | return -ENOMEM; | |
875 | ||
876 | err = -EFAULT; | |
877 | if (copy_from_user(data, optval, optlen)) | |
878 | goto out; | |
879 | ||
880 | err = -EINVAL; | |
881 | read_lock(&xfrm_km_lock); | |
882 | list_for_each_entry(km, &xfrm_km_list, list) { | |
883 | pol = km->compile_policy(sk->sk_family, optname, data, | |
884 | optlen, &err); | |
885 | if (err >= 0) | |
886 | break; | |
887 | } | |
888 | read_unlock(&xfrm_km_lock); | |
889 | ||
890 | if (err >= 0) { | |
891 | xfrm_sk_policy_insert(sk, err, pol); | |
892 | xfrm_pol_put(pol); | |
893 | err = 0; | |
894 | } | |
895 | ||
896 | out: | |
897 | kfree(data); | |
898 | return err; | |
899 | } | |
900 | EXPORT_SYMBOL(xfrm_user_policy); | |
901 | ||
902 | int xfrm_register_km(struct xfrm_mgr *km) | |
903 | { | |
904 | write_lock_bh(&xfrm_km_lock); | |
905 | list_add_tail(&km->list, &xfrm_km_list); | |
906 | write_unlock_bh(&xfrm_km_lock); | |
907 | return 0; | |
908 | } | |
909 | EXPORT_SYMBOL(xfrm_register_km); | |
910 | ||
911 | int xfrm_unregister_km(struct xfrm_mgr *km) | |
912 | { | |
913 | write_lock_bh(&xfrm_km_lock); | |
914 | list_del(&km->list); | |
915 | write_unlock_bh(&xfrm_km_lock); | |
916 | return 0; | |
917 | } | |
918 | EXPORT_SYMBOL(xfrm_unregister_km); | |
919 | ||
920 | int xfrm_state_register_afinfo(struct xfrm_state_afinfo *afinfo) | |
921 | { | |
922 | int err = 0; | |
923 | if (unlikely(afinfo == NULL)) | |
924 | return -EINVAL; | |
925 | if (unlikely(afinfo->family >= NPROTO)) | |
926 | return -EAFNOSUPPORT; | |
927 | write_lock(&xfrm_state_afinfo_lock); | |
928 | if (unlikely(xfrm_state_afinfo[afinfo->family] != NULL)) | |
929 | err = -ENOBUFS; | |
930 | else { | |
931 | afinfo->state_bydst = xfrm_state_bydst; | |
932 | afinfo->state_byspi = xfrm_state_byspi; | |
933 | xfrm_state_afinfo[afinfo->family] = afinfo; | |
934 | } | |
935 | write_unlock(&xfrm_state_afinfo_lock); | |
936 | return err; | |
937 | } | |
938 | EXPORT_SYMBOL(xfrm_state_register_afinfo); | |
939 | ||
940 | int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo) | |
941 | { | |
942 | int err = 0; | |
943 | if (unlikely(afinfo == NULL)) | |
944 | return -EINVAL; | |
945 | if (unlikely(afinfo->family >= NPROTO)) | |
946 | return -EAFNOSUPPORT; | |
947 | write_lock(&xfrm_state_afinfo_lock); | |
948 | if (likely(xfrm_state_afinfo[afinfo->family] != NULL)) { | |
949 | if (unlikely(xfrm_state_afinfo[afinfo->family] != afinfo)) | |
950 | err = -EINVAL; | |
951 | else { | |
952 | xfrm_state_afinfo[afinfo->family] = NULL; | |
953 | afinfo->state_byspi = NULL; | |
954 | afinfo->state_bydst = NULL; | |
955 | } | |
956 | } | |
957 | write_unlock(&xfrm_state_afinfo_lock); | |
958 | return err; | |
959 | } | |
960 | EXPORT_SYMBOL(xfrm_state_unregister_afinfo); | |
961 | ||
962 | static struct xfrm_state_afinfo *xfrm_state_get_afinfo(unsigned short family) | |
963 | { | |
964 | struct xfrm_state_afinfo *afinfo; | |
965 | if (unlikely(family >= NPROTO)) | |
966 | return NULL; | |
967 | read_lock(&xfrm_state_afinfo_lock); | |
968 | afinfo = xfrm_state_afinfo[family]; | |
969 | if (likely(afinfo != NULL)) | |
970 | read_lock(&afinfo->lock); | |
971 | read_unlock(&xfrm_state_afinfo_lock); | |
972 | return afinfo; | |
973 | } | |
974 | ||
975 | static void xfrm_state_put_afinfo(struct xfrm_state_afinfo *afinfo) | |
976 | { | |
977 | if (unlikely(afinfo == NULL)) | |
978 | return; | |
979 | read_unlock(&afinfo->lock); | |
980 | } | |
981 | ||
982 | /* Temporarily located here until net/xfrm/xfrm_tunnel.c is created */ | |
983 | void xfrm_state_delete_tunnel(struct xfrm_state *x) | |
984 | { | |
985 | if (x->tunnel) { | |
986 | struct xfrm_state *t = x->tunnel; | |
987 | ||
988 | if (atomic_read(&t->tunnel_users) == 2) | |
989 | xfrm_state_delete(t); | |
990 | atomic_dec(&t->tunnel_users); | |
991 | xfrm_state_put(t); | |
992 | x->tunnel = NULL; | |
993 | } | |
994 | } | |
995 | EXPORT_SYMBOL(xfrm_state_delete_tunnel); | |
996 | ||
997 | int xfrm_state_mtu(struct xfrm_state *x, int mtu) | |
998 | { | |
999 | int res = mtu; | |
1000 | ||
1001 | res -= x->props.header_len; | |
1002 | ||
1003 | for (;;) { | |
1004 | int m = res; | |
1005 | ||
1006 | if (m < 68) | |
1007 | return 68; | |
1008 | ||
1009 | spin_lock_bh(&x->lock); | |
1010 | if (x->km.state == XFRM_STATE_VALID && | |
1011 | x->type && x->type->get_max_size) | |
1012 | m = x->type->get_max_size(x, m); | |
1013 | else | |
1014 | m += x->props.header_len; | |
1015 | spin_unlock_bh(&x->lock); | |
1016 | ||
1017 | if (m <= mtu) | |
1018 | break; | |
1019 | res -= (m - mtu); | |
1020 | } | |
1021 | ||
1022 | return res; | |
1023 | } | |
1024 | ||
1025 | EXPORT_SYMBOL(xfrm_state_mtu); | |
1026 | ||
1027 | void __init xfrm_state_init(void) | |
1028 | { | |
1029 | int i; | |
1030 | ||
1031 | for (i=0; i<XFRM_DST_HSIZE; i++) { | |
1032 | INIT_LIST_HEAD(&xfrm_state_bydst[i]); | |
1033 | INIT_LIST_HEAD(&xfrm_state_byspi[i]); | |
1034 | } | |
1035 | INIT_WORK(&xfrm_state_gc_work, xfrm_state_gc_task, NULL); | |
1036 | } | |
1037 |