treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / net / xfrm / xfrm_replay.c
blob98943f8d01aa05843b1fd6ff71c8246d0ef5068f
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * xfrm_replay.c - xfrm replay detection, derived from xfrm_state.c.
5 * Copyright (C) 2010 secunet Security Networks AG
6 * Copyright (C) 2010 Steffen Klassert <steffen.klassert@secunet.com>
7 */
9 #include <linux/export.h>
10 #include <net/xfrm.h>
12 u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq)
14 u32 seq, seq_hi, bottom;
15 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
17 if (!(x->props.flags & XFRM_STATE_ESN))
18 return 0;
20 seq = ntohl(net_seq);
21 seq_hi = replay_esn->seq_hi;
22 bottom = replay_esn->seq - replay_esn->replay_window + 1;
24 if (likely(replay_esn->seq >= replay_esn->replay_window - 1)) {
25 /* A. same subspace */
26 if (unlikely(seq < bottom))
27 seq_hi++;
28 } else {
29 /* B. window spans two subspaces */
30 if (unlikely(seq >= bottom))
31 seq_hi--;
34 return seq_hi;
36 EXPORT_SYMBOL(xfrm_replay_seqhi);
38 static void xfrm_replay_notify(struct xfrm_state *x, int event)
40 struct km_event c;
41 /* we send notify messages in case
42 * 1. we updated on of the sequence numbers, and the seqno difference
43 * is at least x->replay_maxdiff, in this case we also update the
44 * timeout of our timer function
45 * 2. if x->replay_maxage has elapsed since last update,
46 * and there were changes
48 * The state structure must be locked!
51 switch (event) {
52 case XFRM_REPLAY_UPDATE:
53 if (!x->replay_maxdiff ||
54 ((x->replay.seq - x->preplay.seq < x->replay_maxdiff) &&
55 (x->replay.oseq - x->preplay.oseq < x->replay_maxdiff))) {
56 if (x->xflags & XFRM_TIME_DEFER)
57 event = XFRM_REPLAY_TIMEOUT;
58 else
59 return;
62 break;
64 case XFRM_REPLAY_TIMEOUT:
65 if (memcmp(&x->replay, &x->preplay,
66 sizeof(struct xfrm_replay_state)) == 0) {
67 x->xflags |= XFRM_TIME_DEFER;
68 return;
71 break;
74 memcpy(&x->preplay, &x->replay, sizeof(struct xfrm_replay_state));
75 c.event = XFRM_MSG_NEWAE;
76 c.data.aevent = event;
77 km_state_notify(x, &c);
79 if (x->replay_maxage &&
80 !mod_timer(&x->rtimer, jiffies + x->replay_maxage))
81 x->xflags &= ~XFRM_TIME_DEFER;
84 static int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
86 int err = 0;
87 struct net *net = xs_net(x);
89 if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
90 XFRM_SKB_CB(skb)->seq.output.low = ++x->replay.oseq;
91 XFRM_SKB_CB(skb)->seq.output.hi = 0;
92 if (unlikely(x->replay.oseq == 0)) {
93 x->replay.oseq--;
94 xfrm_audit_state_replay_overflow(x, skb);
95 err = -EOVERFLOW;
97 return err;
99 if (xfrm_aevent_is_on(net))
100 x->repl->notify(x, XFRM_REPLAY_UPDATE);
103 return err;
106 static int xfrm_replay_check(struct xfrm_state *x,
107 struct sk_buff *skb, __be32 net_seq)
109 u32 diff;
110 u32 seq = ntohl(net_seq);
112 if (!x->props.replay_window)
113 return 0;
115 if (unlikely(seq == 0))
116 goto err;
118 if (likely(seq > x->replay.seq))
119 return 0;
121 diff = x->replay.seq - seq;
122 if (diff >= x->props.replay_window) {
123 x->stats.replay_window++;
124 goto err;
127 if (x->replay.bitmap & (1U << diff)) {
128 x->stats.replay++;
129 goto err;
131 return 0;
133 err:
134 xfrm_audit_state_replay(x, skb, net_seq);
135 return -EINVAL;
138 static void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq)
140 u32 diff;
141 u32 seq = ntohl(net_seq);
143 if (!x->props.replay_window)
144 return;
146 if (seq > x->replay.seq) {
147 diff = seq - x->replay.seq;
148 if (diff < x->props.replay_window)
149 x->replay.bitmap = ((x->replay.bitmap) << diff) | 1;
150 else
151 x->replay.bitmap = 1;
152 x->replay.seq = seq;
153 } else {
154 diff = x->replay.seq - seq;
155 x->replay.bitmap |= (1U << diff);
158 if (xfrm_aevent_is_on(xs_net(x)))
159 x->repl->notify(x, XFRM_REPLAY_UPDATE);
162 static int xfrm_replay_overflow_bmp(struct xfrm_state *x, struct sk_buff *skb)
164 int err = 0;
165 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
166 struct net *net = xs_net(x);
168 if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
169 XFRM_SKB_CB(skb)->seq.output.low = ++replay_esn->oseq;
170 XFRM_SKB_CB(skb)->seq.output.hi = 0;
171 if (unlikely(replay_esn->oseq == 0)) {
172 replay_esn->oseq--;
173 xfrm_audit_state_replay_overflow(x, skb);
174 err = -EOVERFLOW;
176 return err;
178 if (xfrm_aevent_is_on(net))
179 x->repl->notify(x, XFRM_REPLAY_UPDATE);
182 return err;
185 static int xfrm_replay_check_bmp(struct xfrm_state *x,
186 struct sk_buff *skb, __be32 net_seq)
188 unsigned int bitnr, nr;
189 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
190 u32 pos;
191 u32 seq = ntohl(net_seq);
192 u32 diff = replay_esn->seq - seq;
194 if (!replay_esn->replay_window)
195 return 0;
197 if (unlikely(seq == 0))
198 goto err;
200 if (likely(seq > replay_esn->seq))
201 return 0;
203 if (diff >= replay_esn->replay_window) {
204 x->stats.replay_window++;
205 goto err;
208 pos = (replay_esn->seq - 1) % replay_esn->replay_window;
210 if (pos >= diff)
211 bitnr = (pos - diff) % replay_esn->replay_window;
212 else
213 bitnr = replay_esn->replay_window - (diff - pos);
215 nr = bitnr >> 5;
216 bitnr = bitnr & 0x1F;
217 if (replay_esn->bmp[nr] & (1U << bitnr))
218 goto err_replay;
220 return 0;
222 err_replay:
223 x->stats.replay++;
224 err:
225 xfrm_audit_state_replay(x, skb, net_seq);
226 return -EINVAL;
229 static void xfrm_replay_advance_bmp(struct xfrm_state *x, __be32 net_seq)
231 unsigned int bitnr, nr, i;
232 u32 diff;
233 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
234 u32 seq = ntohl(net_seq);
235 u32 pos;
237 if (!replay_esn->replay_window)
238 return;
240 pos = (replay_esn->seq - 1) % replay_esn->replay_window;
242 if (seq > replay_esn->seq) {
243 diff = seq - replay_esn->seq;
245 if (diff < replay_esn->replay_window) {
246 for (i = 1; i < diff; i++) {
247 bitnr = (pos + i) % replay_esn->replay_window;
248 nr = bitnr >> 5;
249 bitnr = bitnr & 0x1F;
250 replay_esn->bmp[nr] &= ~(1U << bitnr);
252 } else {
253 nr = (replay_esn->replay_window - 1) >> 5;
254 for (i = 0; i <= nr; i++)
255 replay_esn->bmp[i] = 0;
258 bitnr = (pos + diff) % replay_esn->replay_window;
259 replay_esn->seq = seq;
260 } else {
261 diff = replay_esn->seq - seq;
263 if (pos >= diff)
264 bitnr = (pos - diff) % replay_esn->replay_window;
265 else
266 bitnr = replay_esn->replay_window - (diff - pos);
269 nr = bitnr >> 5;
270 bitnr = bitnr & 0x1F;
271 replay_esn->bmp[nr] |= (1U << bitnr);
273 if (xfrm_aevent_is_on(xs_net(x)))
274 x->repl->notify(x, XFRM_REPLAY_UPDATE);
277 static void xfrm_replay_notify_bmp(struct xfrm_state *x, int event)
279 struct km_event c;
280 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
281 struct xfrm_replay_state_esn *preplay_esn = x->preplay_esn;
283 /* we send notify messages in case
284 * 1. we updated on of the sequence numbers, and the seqno difference
285 * is at least x->replay_maxdiff, in this case we also update the
286 * timeout of our timer function
287 * 2. if x->replay_maxage has elapsed since last update,
288 * and there were changes
290 * The state structure must be locked!
293 switch (event) {
294 case XFRM_REPLAY_UPDATE:
295 if (!x->replay_maxdiff ||
296 ((replay_esn->seq - preplay_esn->seq < x->replay_maxdiff) &&
297 (replay_esn->oseq - preplay_esn->oseq
298 < x->replay_maxdiff))) {
299 if (x->xflags & XFRM_TIME_DEFER)
300 event = XFRM_REPLAY_TIMEOUT;
301 else
302 return;
305 break;
307 case XFRM_REPLAY_TIMEOUT:
308 if (memcmp(x->replay_esn, x->preplay_esn,
309 xfrm_replay_state_esn_len(replay_esn)) == 0) {
310 x->xflags |= XFRM_TIME_DEFER;
311 return;
314 break;
317 memcpy(x->preplay_esn, x->replay_esn,
318 xfrm_replay_state_esn_len(replay_esn));
319 c.event = XFRM_MSG_NEWAE;
320 c.data.aevent = event;
321 km_state_notify(x, &c);
323 if (x->replay_maxage &&
324 !mod_timer(&x->rtimer, jiffies + x->replay_maxage))
325 x->xflags &= ~XFRM_TIME_DEFER;
328 static void xfrm_replay_notify_esn(struct xfrm_state *x, int event)
330 u32 seq_diff, oseq_diff;
331 struct km_event c;
332 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
333 struct xfrm_replay_state_esn *preplay_esn = x->preplay_esn;
335 /* we send notify messages in case
336 * 1. we updated on of the sequence numbers, and the seqno difference
337 * is at least x->replay_maxdiff, in this case we also update the
338 * timeout of our timer function
339 * 2. if x->replay_maxage has elapsed since last update,
340 * and there were changes
342 * The state structure must be locked!
345 switch (event) {
346 case XFRM_REPLAY_UPDATE:
347 if (x->replay_maxdiff) {
348 if (replay_esn->seq_hi == preplay_esn->seq_hi)
349 seq_diff = replay_esn->seq - preplay_esn->seq;
350 else
351 seq_diff = ~preplay_esn->seq + replay_esn->seq
352 + 1;
354 if (replay_esn->oseq_hi == preplay_esn->oseq_hi)
355 oseq_diff = replay_esn->oseq
356 - preplay_esn->oseq;
357 else
358 oseq_diff = ~preplay_esn->oseq
359 + replay_esn->oseq + 1;
361 if (seq_diff >= x->replay_maxdiff ||
362 oseq_diff >= x->replay_maxdiff)
363 break;
366 if (x->xflags & XFRM_TIME_DEFER)
367 event = XFRM_REPLAY_TIMEOUT;
368 else
369 return;
371 break;
373 case XFRM_REPLAY_TIMEOUT:
374 if (memcmp(x->replay_esn, x->preplay_esn,
375 xfrm_replay_state_esn_len(replay_esn)) == 0) {
376 x->xflags |= XFRM_TIME_DEFER;
377 return;
380 break;
383 memcpy(x->preplay_esn, x->replay_esn,
384 xfrm_replay_state_esn_len(replay_esn));
385 c.event = XFRM_MSG_NEWAE;
386 c.data.aevent = event;
387 km_state_notify(x, &c);
389 if (x->replay_maxage &&
390 !mod_timer(&x->rtimer, jiffies + x->replay_maxage))
391 x->xflags &= ~XFRM_TIME_DEFER;
394 static int xfrm_replay_overflow_esn(struct xfrm_state *x, struct sk_buff *skb)
396 int err = 0;
397 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
398 struct net *net = xs_net(x);
400 if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
401 XFRM_SKB_CB(skb)->seq.output.low = ++replay_esn->oseq;
402 XFRM_SKB_CB(skb)->seq.output.hi = replay_esn->oseq_hi;
404 if (unlikely(replay_esn->oseq == 0)) {
405 XFRM_SKB_CB(skb)->seq.output.hi = ++replay_esn->oseq_hi;
407 if (replay_esn->oseq_hi == 0) {
408 replay_esn->oseq--;
409 replay_esn->oseq_hi--;
410 xfrm_audit_state_replay_overflow(x, skb);
411 err = -EOVERFLOW;
413 return err;
416 if (xfrm_aevent_is_on(net))
417 x->repl->notify(x, XFRM_REPLAY_UPDATE);
420 return err;
423 static int xfrm_replay_check_esn(struct xfrm_state *x,
424 struct sk_buff *skb, __be32 net_seq)
426 unsigned int bitnr, nr;
427 u32 diff;
428 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
429 u32 pos;
430 u32 seq = ntohl(net_seq);
431 u32 wsize = replay_esn->replay_window;
432 u32 top = replay_esn->seq;
433 u32 bottom = top - wsize + 1;
435 if (!wsize)
436 return 0;
438 if (unlikely(seq == 0 && replay_esn->seq_hi == 0 &&
439 (replay_esn->seq < replay_esn->replay_window - 1)))
440 goto err;
442 diff = top - seq;
444 if (likely(top >= wsize - 1)) {
445 /* A. same subspace */
446 if (likely(seq > top) || seq < bottom)
447 return 0;
448 } else {
449 /* B. window spans two subspaces */
450 if (likely(seq > top && seq < bottom))
451 return 0;
452 if (seq >= bottom)
453 diff = ~seq + top + 1;
456 if (diff >= replay_esn->replay_window) {
457 x->stats.replay_window++;
458 goto err;
461 pos = (replay_esn->seq - 1) % replay_esn->replay_window;
463 if (pos >= diff)
464 bitnr = (pos - diff) % replay_esn->replay_window;
465 else
466 bitnr = replay_esn->replay_window - (diff - pos);
468 nr = bitnr >> 5;
469 bitnr = bitnr & 0x1F;
470 if (replay_esn->bmp[nr] & (1U << bitnr))
471 goto err_replay;
473 return 0;
475 err_replay:
476 x->stats.replay++;
477 err:
478 xfrm_audit_state_replay(x, skb, net_seq);
479 return -EINVAL;
482 static int xfrm_replay_recheck_esn(struct xfrm_state *x,
483 struct sk_buff *skb, __be32 net_seq)
485 if (unlikely(XFRM_SKB_CB(skb)->seq.input.hi !=
486 htonl(xfrm_replay_seqhi(x, net_seq)))) {
487 x->stats.replay_window++;
488 return -EINVAL;
491 return xfrm_replay_check_esn(x, skb, net_seq);
494 static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq)
496 unsigned int bitnr, nr, i;
497 int wrap;
498 u32 diff, pos, seq, seq_hi;
499 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
501 if (!replay_esn->replay_window)
502 return;
504 seq = ntohl(net_seq);
505 pos = (replay_esn->seq - 1) % replay_esn->replay_window;
506 seq_hi = xfrm_replay_seqhi(x, net_seq);
507 wrap = seq_hi - replay_esn->seq_hi;
509 if ((!wrap && seq > replay_esn->seq) || wrap > 0) {
510 if (likely(!wrap))
511 diff = seq - replay_esn->seq;
512 else
513 diff = ~replay_esn->seq + seq + 1;
515 if (diff < replay_esn->replay_window) {
516 for (i = 1; i < diff; i++) {
517 bitnr = (pos + i) % replay_esn->replay_window;
518 nr = bitnr >> 5;
519 bitnr = bitnr & 0x1F;
520 replay_esn->bmp[nr] &= ~(1U << bitnr);
522 } else {
523 nr = (replay_esn->replay_window - 1) >> 5;
524 for (i = 0; i <= nr; i++)
525 replay_esn->bmp[i] = 0;
528 bitnr = (pos + diff) % replay_esn->replay_window;
529 replay_esn->seq = seq;
531 if (unlikely(wrap > 0))
532 replay_esn->seq_hi++;
533 } else {
534 diff = replay_esn->seq - seq;
536 if (pos >= diff)
537 bitnr = (pos - diff) % replay_esn->replay_window;
538 else
539 bitnr = replay_esn->replay_window - (diff - pos);
542 xfrm_dev_state_advance_esn(x);
544 nr = bitnr >> 5;
545 bitnr = bitnr & 0x1F;
546 replay_esn->bmp[nr] |= (1U << bitnr);
548 if (xfrm_aevent_is_on(xs_net(x)))
549 x->repl->notify(x, XFRM_REPLAY_UPDATE);
552 #ifdef CONFIG_XFRM_OFFLOAD
553 static int xfrm_replay_overflow_offload(struct xfrm_state *x, struct sk_buff *skb)
555 int err = 0;
556 struct net *net = xs_net(x);
557 struct xfrm_offload *xo = xfrm_offload(skb);
558 __u32 oseq = x->replay.oseq;
560 if (!xo)
561 return xfrm_replay_overflow(x, skb);
563 if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
564 if (!skb_is_gso(skb)) {
565 XFRM_SKB_CB(skb)->seq.output.low = ++oseq;
566 xo->seq.low = oseq;
567 } else {
568 XFRM_SKB_CB(skb)->seq.output.low = oseq + 1;
569 xo->seq.low = oseq + 1;
570 oseq += skb_shinfo(skb)->gso_segs;
573 XFRM_SKB_CB(skb)->seq.output.hi = 0;
574 xo->seq.hi = 0;
575 if (unlikely(oseq < x->replay.oseq)) {
576 xfrm_audit_state_replay_overflow(x, skb);
577 err = -EOVERFLOW;
579 return err;
582 x->replay.oseq = oseq;
584 if (xfrm_aevent_is_on(net))
585 x->repl->notify(x, XFRM_REPLAY_UPDATE);
588 return err;
591 static int xfrm_replay_overflow_offload_bmp(struct xfrm_state *x, struct sk_buff *skb)
593 int err = 0;
594 struct xfrm_offload *xo = xfrm_offload(skb);
595 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
596 struct net *net = xs_net(x);
597 __u32 oseq = replay_esn->oseq;
599 if (!xo)
600 return xfrm_replay_overflow_bmp(x, skb);
602 if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
603 if (!skb_is_gso(skb)) {
604 XFRM_SKB_CB(skb)->seq.output.low = ++oseq;
605 xo->seq.low = oseq;
606 } else {
607 XFRM_SKB_CB(skb)->seq.output.low = oseq + 1;
608 xo->seq.low = oseq + 1;
609 oseq += skb_shinfo(skb)->gso_segs;
612 XFRM_SKB_CB(skb)->seq.output.hi = 0;
613 xo->seq.hi = 0;
614 if (unlikely(oseq < replay_esn->oseq)) {
615 xfrm_audit_state_replay_overflow(x, skb);
616 err = -EOVERFLOW;
618 return err;
619 } else {
620 replay_esn->oseq = oseq;
623 if (xfrm_aevent_is_on(net))
624 x->repl->notify(x, XFRM_REPLAY_UPDATE);
627 return err;
630 static int xfrm_replay_overflow_offload_esn(struct xfrm_state *x, struct sk_buff *skb)
632 int err = 0;
633 struct xfrm_offload *xo = xfrm_offload(skb);
634 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
635 struct net *net = xs_net(x);
636 __u32 oseq = replay_esn->oseq;
637 __u32 oseq_hi = replay_esn->oseq_hi;
639 if (!xo)
640 return xfrm_replay_overflow_esn(x, skb);
642 if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
643 if (!skb_is_gso(skb)) {
644 XFRM_SKB_CB(skb)->seq.output.low = ++oseq;
645 XFRM_SKB_CB(skb)->seq.output.hi = oseq_hi;
646 xo->seq.low = oseq;
647 xo->seq.hi = oseq_hi;
648 } else {
649 XFRM_SKB_CB(skb)->seq.output.low = oseq + 1;
650 XFRM_SKB_CB(skb)->seq.output.hi = oseq_hi;
651 xo->seq.low = oseq + 1;
652 xo->seq.hi = oseq_hi;
653 oseq += skb_shinfo(skb)->gso_segs;
656 if (unlikely(oseq < replay_esn->oseq)) {
657 XFRM_SKB_CB(skb)->seq.output.hi = ++oseq_hi;
658 xo->seq.hi = oseq_hi;
659 replay_esn->oseq_hi = oseq_hi;
660 if (replay_esn->oseq_hi == 0) {
661 replay_esn->oseq--;
662 replay_esn->oseq_hi--;
663 xfrm_audit_state_replay_overflow(x, skb);
664 err = -EOVERFLOW;
666 return err;
670 replay_esn->oseq = oseq;
672 if (xfrm_aevent_is_on(net))
673 x->repl->notify(x, XFRM_REPLAY_UPDATE);
676 return err;
679 static const struct xfrm_replay xfrm_replay_legacy = {
680 .advance = xfrm_replay_advance,
681 .check = xfrm_replay_check,
682 .recheck = xfrm_replay_check,
683 .notify = xfrm_replay_notify,
684 .overflow = xfrm_replay_overflow_offload,
687 static const struct xfrm_replay xfrm_replay_bmp = {
688 .advance = xfrm_replay_advance_bmp,
689 .check = xfrm_replay_check_bmp,
690 .recheck = xfrm_replay_check_bmp,
691 .notify = xfrm_replay_notify_bmp,
692 .overflow = xfrm_replay_overflow_offload_bmp,
695 static const struct xfrm_replay xfrm_replay_esn = {
696 .advance = xfrm_replay_advance_esn,
697 .check = xfrm_replay_check_esn,
698 .recheck = xfrm_replay_recheck_esn,
699 .notify = xfrm_replay_notify_esn,
700 .overflow = xfrm_replay_overflow_offload_esn,
702 #else
703 static const struct xfrm_replay xfrm_replay_legacy = {
704 .advance = xfrm_replay_advance,
705 .check = xfrm_replay_check,
706 .recheck = xfrm_replay_check,
707 .notify = xfrm_replay_notify,
708 .overflow = xfrm_replay_overflow,
711 static const struct xfrm_replay xfrm_replay_bmp = {
712 .advance = xfrm_replay_advance_bmp,
713 .check = xfrm_replay_check_bmp,
714 .recheck = xfrm_replay_check_bmp,
715 .notify = xfrm_replay_notify_bmp,
716 .overflow = xfrm_replay_overflow_bmp,
719 static const struct xfrm_replay xfrm_replay_esn = {
720 .advance = xfrm_replay_advance_esn,
721 .check = xfrm_replay_check_esn,
722 .recheck = xfrm_replay_recheck_esn,
723 .notify = xfrm_replay_notify_esn,
724 .overflow = xfrm_replay_overflow_esn,
726 #endif
728 int xfrm_init_replay(struct xfrm_state *x)
730 struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
732 if (replay_esn) {
733 if (replay_esn->replay_window >
734 replay_esn->bmp_len * sizeof(__u32) * 8)
735 return -EINVAL;
737 if (x->props.flags & XFRM_STATE_ESN) {
738 if (replay_esn->replay_window == 0)
739 return -EINVAL;
740 x->repl = &xfrm_replay_esn;
741 } else {
742 x->repl = &xfrm_replay_bmp;
744 } else {
745 x->repl = &xfrm_replay_legacy;
748 return 0;
750 EXPORT_SYMBOL(xfrm_init_replay);