-
Notifications
You must be signed in to change notification settings - Fork 53.6k
/
gcm.c
1214 lines (966 loc) · 31 KB
/
gcm.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// SPDX-License-Identifier: GPL-2.0-only
/*
* GCM: Galois/Counter Mode.
*
* Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <[email protected]>
*/
#include <crypto/gf128mul.h>
#include <crypto/internal/aead.h>
#include <crypto/internal/skcipher.h>
#include <crypto/internal/hash.h>
#include <crypto/null.h>
#include <crypto/scatterwalk.h>
#include <crypto/gcm.h>
#include <crypto/hash.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
struct gcm_instance_ctx {
struct crypto_skcipher_spawn ctr;
struct crypto_ahash_spawn ghash;
};
struct crypto_gcm_ctx {
struct crypto_skcipher *ctr;
struct crypto_ahash *ghash;
};
struct crypto_rfc4106_ctx {
struct crypto_aead *child;
u8 nonce[4];
};
struct crypto_rfc4106_req_ctx {
struct scatterlist src[3];
struct scatterlist dst[3];
struct aead_request subreq;
};
struct crypto_rfc4543_instance_ctx {
struct crypto_aead_spawn aead;
};
struct crypto_rfc4543_ctx {
struct crypto_aead *child;
struct crypto_sync_skcipher *null;
u8 nonce[4];
};
struct crypto_rfc4543_req_ctx {
struct aead_request subreq;
};
struct crypto_gcm_ghash_ctx {
unsigned int cryptlen;
struct scatterlist *src;
int (*complete)(struct aead_request *req, u32 flags);
};
struct crypto_gcm_req_priv_ctx {
u8 iv[16];
u8 auth_tag[16];
u8 iauth_tag[16];
struct scatterlist src[3];
struct scatterlist dst[3];
struct scatterlist sg;
struct crypto_gcm_ghash_ctx ghash_ctx;
union {
struct ahash_request ahreq;
struct skcipher_request skreq;
} u;
};
static struct {
u8 buf[16];
struct scatterlist sg;
} *gcm_zeroes;
static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc);
static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
struct aead_request *req)
{
unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
}
static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
unsigned int keylen)
{
struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_ahash *ghash = ctx->ghash;
struct crypto_skcipher *ctr = ctx->ctr;
struct {
be128 hash;
u8 iv[16];
struct crypto_wait wait;
struct scatterlist sg[1];
struct skcipher_request req;
} *data;
int err;
crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
CRYPTO_TFM_REQ_MASK);
err = crypto_skcipher_setkey(ctr, key, keylen);
if (err)
return err;
data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr),
GFP_KERNEL);
if (!data)
return -ENOMEM;
crypto_init_wait(&data->wait);
sg_init_one(data->sg, &data->hash, sizeof(data->hash));
skcipher_request_set_tfm(&data->req, ctr);
skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
CRYPTO_TFM_REQ_MAY_BACKLOG,
crypto_req_done,
&data->wait);
skcipher_request_set_crypt(&data->req, data->sg, data->sg,
sizeof(data->hash), data->iv);
err = crypto_wait_req(crypto_skcipher_encrypt(&data->req),
&data->wait);
if (err)
goto out;
crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK);
crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) &
CRYPTO_TFM_REQ_MASK);
err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128));
out:
kzfree(data);
return err;
}
static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
unsigned int authsize)
{
return crypto_gcm_check_authsize(authsize);
}
static void crypto_gcm_init_common(struct aead_request *req)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
__be32 counter = cpu_to_be32(1);
struct scatterlist *sg;
memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
memcpy(pctx->iv, req->iv, GCM_AES_IV_SIZE);
memcpy(pctx->iv + GCM_AES_IV_SIZE, &counter, 4);
sg_init_table(pctx->src, 3);
sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
if (sg != pctx->src + 1)
sg_chain(pctx->src, 2, sg);
if (req->src != req->dst) {
sg_init_table(pctx->dst, 3);
sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag));
sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
if (sg != pctx->dst + 1)
sg_chain(pctx->dst, 2, sg);
}
}
static void crypto_gcm_init_crypt(struct aead_request *req,
unsigned int cryptlen)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct skcipher_request *skreq = &pctx->u.skreq;
struct scatterlist *dst;
dst = req->src == req->dst ? pctx->src : pctx->dst;
skcipher_request_set_tfm(skreq, ctx->ctr);
skcipher_request_set_crypt(skreq, pctx->src, dst,
cryptlen + sizeof(pctx->auth_tag),
pctx->iv);
}
static inline unsigned int gcm_remain(unsigned int len)
{
len &= 0xfU;
return len ? 16 - len : 0;
}
static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
static int gcm_hash_update(struct aead_request *req,
crypto_completion_t compl,
struct scatterlist *src,
unsigned int len, u32 flags)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct ahash_request *ahreq = &pctx->u.ahreq;
ahash_request_set_callback(ahreq, flags, compl, req);
ahash_request_set_crypt(ahreq, src, NULL, len);
return crypto_ahash_update(ahreq);
}
static int gcm_hash_remain(struct aead_request *req,
unsigned int remain,
crypto_completion_t compl, u32 flags)
{
return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags);
}
static int gcm_hash_len(struct aead_request *req, u32 flags)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct ahash_request *ahreq = &pctx->u.ahreq;
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
be128 lengths;
lengths.a = cpu_to_be64(req->assoclen * 8);
lengths.b = cpu_to_be64(gctx->cryptlen * 8);
memcpy(pctx->iauth_tag, &lengths, 16);
sg_init_one(&pctx->sg, pctx->iauth_tag, 16);
ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req);
ahash_request_set_crypt(ahreq, &pctx->sg,
pctx->iauth_tag, sizeof(lengths));
return crypto_ahash_finup(ahreq);
}
static int gcm_hash_len_continue(struct aead_request *req, u32 flags)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
return gctx->complete(req, flags);
}
static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
if (err)
goto out;
err = gcm_hash_len_continue(req, 0);
if (err == -EINPROGRESS)
return;
out:
aead_request_complete(req, err);
}
static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags)
{
return gcm_hash_len(req, flags) ?:
gcm_hash_len_continue(req, flags);
}
static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
int err)
{
struct aead_request *req = areq->data;
if (err)
goto out;
err = gcm_hash_crypt_remain_continue(req, 0);
if (err == -EINPROGRESS)
return;
out:
aead_request_complete(req, err);
}
static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
unsigned int remain;
remain = gcm_remain(gctx->cryptlen);
if (remain)
return gcm_hash_remain(req, remain,
gcm_hash_crypt_remain_done, flags) ?:
gcm_hash_crypt_remain_continue(req, flags);
return gcm_hash_crypt_remain_continue(req, flags);
}
static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
if (err)
goto out;
err = gcm_hash_crypt_continue(req, 0);
if (err == -EINPROGRESS)
return;
out:
aead_request_complete(req, err);
}
static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
if (gctx->cryptlen)
return gcm_hash_update(req, gcm_hash_crypt_done,
gctx->src, gctx->cryptlen, flags) ?:
gcm_hash_crypt_continue(req, flags);
return gcm_hash_crypt_remain_continue(req, flags);
}
static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
int err)
{
struct aead_request *req = areq->data;
if (err)
goto out;
err = gcm_hash_assoc_remain_continue(req, 0);
if (err == -EINPROGRESS)
return;
out:
aead_request_complete(req, err);
}
static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags)
{
unsigned int remain;
remain = gcm_remain(req->assoclen);
if (remain)
return gcm_hash_remain(req, remain,
gcm_hash_assoc_remain_done, flags) ?:
gcm_hash_assoc_remain_continue(req, flags);
return gcm_hash_assoc_remain_continue(req, flags);
}
static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
if (err)
goto out;
err = gcm_hash_assoc_continue(req, 0);
if (err == -EINPROGRESS)
return;
out:
aead_request_complete(req, err);
}
static int gcm_hash_init_continue(struct aead_request *req, u32 flags)
{
if (req->assoclen)
return gcm_hash_update(req, gcm_hash_assoc_done,
req->src, req->assoclen, flags) ?:
gcm_hash_assoc_continue(req, flags);
return gcm_hash_assoc_remain_continue(req, flags);
}
static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
if (err)
goto out;
err = gcm_hash_init_continue(req, 0);
if (err == -EINPROGRESS)
return;
out:
aead_request_complete(req, err);
}
static int gcm_hash(struct aead_request *req, u32 flags)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct ahash_request *ahreq = &pctx->u.ahreq;
struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
ahash_request_set_tfm(ahreq, ctx->ghash);
ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req);
return crypto_ahash_init(ahreq) ?:
gcm_hash_init_continue(req, flags);
}
static int gcm_enc_copy_hash(struct aead_request *req, u32 flags)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct crypto_aead *aead = crypto_aead_reqtfm(req);
u8 *auth_tag = pctx->auth_tag;
crypto_xor(auth_tag, pctx->iauth_tag, 16);
scatterwalk_map_and_copy(auth_tag, req->dst,
req->assoclen + req->cryptlen,
crypto_aead_authsize(aead), 1);
return 0;
}
static int gcm_encrypt_continue(struct aead_request *req, u32 flags)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
gctx->cryptlen = req->cryptlen;
gctx->complete = gcm_enc_copy_hash;
return gcm_hash(req, flags);
}
static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
if (err)
goto out;
err = gcm_encrypt_continue(req, 0);
if (err == -EINPROGRESS)
return;
out:
aead_request_complete(req, err);
}
static int crypto_gcm_encrypt(struct aead_request *req)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct skcipher_request *skreq = &pctx->u.skreq;
u32 flags = aead_request_flags(req);
crypto_gcm_init_common(req);
crypto_gcm_init_crypt(req, req->cryptlen);
skcipher_request_set_callback(skreq, flags, gcm_encrypt_done, req);
return crypto_skcipher_encrypt(skreq) ?:
gcm_encrypt_continue(req, flags);
}
static int crypto_gcm_verify(struct aead_request *req)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct crypto_aead *aead = crypto_aead_reqtfm(req);
u8 *auth_tag = pctx->auth_tag;
u8 *iauth_tag = pctx->iauth_tag;
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int cryptlen = req->cryptlen - authsize;
crypto_xor(auth_tag, iauth_tag, 16);
scatterwalk_map_and_copy(iauth_tag, req->src,
req->assoclen + cryptlen, authsize, 0);
return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
}
static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
if (!err)
err = crypto_gcm_verify(req);
aead_request_complete(req, err);
}
static int gcm_dec_hash_continue(struct aead_request *req, u32 flags)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct skcipher_request *skreq = &pctx->u.skreq;
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
crypto_gcm_init_crypt(req, gctx->cryptlen);
skcipher_request_set_callback(skreq, flags, gcm_decrypt_done, req);
return crypto_skcipher_decrypt(skreq) ?: crypto_gcm_verify(req);
}
static int crypto_gcm_decrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int cryptlen = req->cryptlen;
u32 flags = aead_request_flags(req);
cryptlen -= authsize;
crypto_gcm_init_common(req);
gctx->src = sg_next(pctx->src);
gctx->cryptlen = cryptlen;
gctx->complete = gcm_dec_hash_continue;
return gcm_hash(req, flags);
}
static int crypto_gcm_init_tfm(struct crypto_aead *tfm)
{
struct aead_instance *inst = aead_alg_instance(tfm);
struct gcm_instance_ctx *ictx = aead_instance_ctx(inst);
struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
struct crypto_skcipher *ctr;
struct crypto_ahash *ghash;
unsigned long align;
int err;
ghash = crypto_spawn_ahash(&ictx->ghash);
if (IS_ERR(ghash))
return PTR_ERR(ghash);
ctr = crypto_spawn_skcipher(&ictx->ctr);
err = PTR_ERR(ctr);
if (IS_ERR(ctr))
goto err_free_hash;
ctx->ctr = ctr;
ctx->ghash = ghash;
align = crypto_aead_alignmask(tfm);
align &= ~(crypto_tfm_ctx_alignment() - 1);
crypto_aead_set_reqsize(tfm,
align + offsetof(struct crypto_gcm_req_priv_ctx, u) +
max(sizeof(struct skcipher_request) +
crypto_skcipher_reqsize(ctr),
sizeof(struct ahash_request) +
crypto_ahash_reqsize(ghash)));
return 0;
err_free_hash:
crypto_free_ahash(ghash);
return err;
}
static void crypto_gcm_exit_tfm(struct crypto_aead *tfm)
{
struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
crypto_free_ahash(ctx->ghash);
crypto_free_skcipher(ctx->ctr);
}
static void crypto_gcm_free(struct aead_instance *inst)
{
struct gcm_instance_ctx *ctx = aead_instance_ctx(inst);
crypto_drop_skcipher(&ctx->ctr);
crypto_drop_ahash(&ctx->ghash);
kfree(inst);
}
static int crypto_gcm_create_common(struct crypto_template *tmpl,
struct rtattr **tb,
const char *ctr_name,
const char *ghash_name)
{
struct crypto_attr_type *algt;
u32 mask;
struct aead_instance *inst;
struct gcm_instance_ctx *ctx;
struct skcipher_alg *ctr;
struct hash_alg_common *ghash;
int err;
algt = crypto_get_attr_type(tb);
if (IS_ERR(algt))
return PTR_ERR(algt);
if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
return -EINVAL;
mask = crypto_requires_sync(algt->type, algt->mask);
inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
if (!inst)
return -ENOMEM;
ctx = aead_instance_ctx(inst);
err = crypto_grab_ahash(&ctx->ghash, aead_crypto_instance(inst),
ghash_name, 0, mask);
if (err)
goto err_free_inst;
ghash = crypto_spawn_ahash_alg(&ctx->ghash);
err = -EINVAL;
if (strcmp(ghash->base.cra_name, "ghash") != 0 ||
ghash->digestsize != 16)
goto err_free_inst;
err = crypto_grab_skcipher(&ctx->ctr, aead_crypto_instance(inst),
ctr_name, 0, mask);
if (err)
goto err_free_inst;
ctr = crypto_spawn_skcipher_alg(&ctx->ctr);
/* The skcipher algorithm must be CTR mode, using 16-byte blocks. */
err = -EINVAL;
if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 ||
crypto_skcipher_alg_ivsize(ctr) != 16 ||
ctr->base.cra_blocksize != 1)
goto err_free_inst;
err = -ENAMETOOLONG;
if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
"gcm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME)
goto err_free_inst;
if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"gcm_base(%s,%s)", ctr->base.cra_driver_name,
ghash->base.cra_driver_name) >=
CRYPTO_MAX_ALG_NAME)
goto err_free_inst;
inst->alg.base.cra_flags = (ghash->base.cra_flags |
ctr->base.cra_flags) & CRYPTO_ALG_ASYNC;
inst->alg.base.cra_priority = (ghash->base.cra_priority +
ctr->base.cra_priority) / 2;
inst->alg.base.cra_blocksize = 1;
inst->alg.base.cra_alignmask = ghash->base.cra_alignmask |
ctr->base.cra_alignmask;
inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx);
inst->alg.ivsize = GCM_AES_IV_SIZE;
inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
inst->alg.maxauthsize = 16;
inst->alg.init = crypto_gcm_init_tfm;
inst->alg.exit = crypto_gcm_exit_tfm;
inst->alg.setkey = crypto_gcm_setkey;
inst->alg.setauthsize = crypto_gcm_setauthsize;
inst->alg.encrypt = crypto_gcm_encrypt;
inst->alg.decrypt = crypto_gcm_decrypt;
inst->free = crypto_gcm_free;
err = aead_register_instance(tmpl, inst);
if (err) {
err_free_inst:
crypto_gcm_free(inst);
}
return err;
}
static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb)
{
const char *cipher_name;
char ctr_name[CRYPTO_MAX_ALG_NAME];
cipher_name = crypto_attr_alg_name(tb[1]);
if (IS_ERR(cipher_name))
return PTR_ERR(cipher_name);
if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
CRYPTO_MAX_ALG_NAME)
return -ENAMETOOLONG;
return crypto_gcm_create_common(tmpl, tb, ctr_name, "ghash");
}
static int crypto_gcm_base_create(struct crypto_template *tmpl,
struct rtattr **tb)
{
const char *ctr_name;
const char *ghash_name;
ctr_name = crypto_attr_alg_name(tb[1]);
if (IS_ERR(ctr_name))
return PTR_ERR(ctr_name);
ghash_name = crypto_attr_alg_name(tb[2]);
if (IS_ERR(ghash_name))
return PTR_ERR(ghash_name);
return crypto_gcm_create_common(tmpl, tb, ctr_name, ghash_name);
}
static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
unsigned int keylen)
{
struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
struct crypto_aead *child = ctx->child;
if (keylen < 4)
return -EINVAL;
keylen -= 4;
memcpy(ctx->nonce, key + keylen, 4);
crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
CRYPTO_TFM_REQ_MASK);
return crypto_aead_setkey(child, key, keylen);
}
static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
unsigned int authsize)
{
struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
int err;
err = crypto_rfc4106_check_authsize(authsize);
if (err)
return err;
return crypto_aead_setauthsize(ctx->child, authsize);
}
static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
{
struct crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req);
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead);
struct aead_request *subreq = &rctx->subreq;
struct crypto_aead *child = ctx->child;
struct scatterlist *sg;
u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
crypto_aead_alignmask(child) + 1);
scatterwalk_map_and_copy(iv + GCM_AES_IV_SIZE, req->src, 0, req->assoclen - 8, 0);
memcpy(iv, ctx->nonce, 4);
memcpy(iv + 4, req->iv, 8);
sg_init_table(rctx->src, 3);
sg_set_buf(rctx->src, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
if (sg != rctx->src + 1)
sg_chain(rctx->src, 2, sg);
if (req->src != req->dst) {
sg_init_table(rctx->dst, 3);
sg_set_buf(rctx->dst, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
if (sg != rctx->dst + 1)
sg_chain(rctx->dst, 2, sg);
}
aead_request_set_tfm(subreq, child);
aead_request_set_callback(subreq, req->base.flags, req->base.complete,
req->base.data);
aead_request_set_crypt(subreq, rctx->src,
req->src == req->dst ? rctx->src : rctx->dst,
req->cryptlen, iv);
aead_request_set_ad(subreq, req->assoclen - 8);
return subreq;
}
static int crypto_rfc4106_encrypt(struct aead_request *req)
{
int err;
err = crypto_ipsec_check_assoclen(req->assoclen);
if (err)
return err;
req = crypto_rfc4106_crypt(req);
return crypto_aead_encrypt(req);
}
static int crypto_rfc4106_decrypt(struct aead_request *req)
{
int err;
err = crypto_ipsec_check_assoclen(req->assoclen);
if (err)
return err;
req = crypto_rfc4106_crypt(req);
return crypto_aead_decrypt(req);
}
static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm)
{
struct aead_instance *inst = aead_alg_instance(tfm);
struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
struct crypto_aead *aead;
unsigned long align;
aead = crypto_spawn_aead(spawn);
if (IS_ERR(aead))
return PTR_ERR(aead);
ctx->child = aead;
align = crypto_aead_alignmask(aead);
align &= ~(crypto_tfm_ctx_alignment() - 1);
crypto_aead_set_reqsize(
tfm,
sizeof(struct crypto_rfc4106_req_ctx) +
ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
align + 24);
return 0;
}
static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm)
{
struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
crypto_free_aead(ctx->child);
}
static void crypto_rfc4106_free(struct aead_instance *inst)
{
crypto_drop_aead(aead_instance_ctx(inst));
kfree(inst);
}
static int crypto_rfc4106_create(struct crypto_template *tmpl,
struct rtattr **tb)
{
struct crypto_attr_type *algt;
u32 mask;
struct aead_instance *inst;
struct crypto_aead_spawn *spawn;
struct aead_alg *alg;
const char *ccm_name;
int err;
algt = crypto_get_attr_type(tb);
if (IS_ERR(algt))
return PTR_ERR(algt);
if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
return -EINVAL;
mask = crypto_requires_sync(algt->type, algt->mask);
ccm_name = crypto_attr_alg_name(tb[1]);
if (IS_ERR(ccm_name))
return PTR_ERR(ccm_name);
inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
if (!inst)
return -ENOMEM;
spawn = aead_instance_ctx(inst);
err = crypto_grab_aead(spawn, aead_crypto_instance(inst),
ccm_name, 0, mask);
if (err)
goto out_free_inst;
alg = crypto_spawn_aead_alg(spawn);
err = -EINVAL;
/* Underlying IV size must be 12. */
if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
goto out_drop_alg;
/* Not a stream cipher? */
if (alg->base.cra_blocksize != 1)
goto out_drop_alg;
err = -ENAMETOOLONG;
if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
"rfc4106(%s)", alg->base.cra_name) >=
CRYPTO_MAX_ALG_NAME ||
snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"rfc4106(%s)", alg->base.cra_driver_name) >=
CRYPTO_MAX_ALG_NAME)
goto out_drop_alg;
inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
inst->alg.base.cra_priority = alg->base.cra_priority;
inst->alg.base.cra_blocksize = 1;
inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
inst->alg.ivsize = GCM_RFC4106_IV_SIZE;
inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
inst->alg.init = crypto_rfc4106_init_tfm;
inst->alg.exit = crypto_rfc4106_exit_tfm;
inst->alg.setkey = crypto_rfc4106_setkey;
inst->alg.setauthsize = crypto_rfc4106_setauthsize;
inst->alg.encrypt = crypto_rfc4106_encrypt;
inst->alg.decrypt = crypto_rfc4106_decrypt;
inst->free = crypto_rfc4106_free;
err = aead_register_instance(tmpl, inst);
if (err)
goto out_drop_alg;
out:
return err;
out_drop_alg:
crypto_drop_aead(spawn);
out_free_inst:
kfree(inst);
goto out;
}
static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
unsigned int keylen)
{
struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
struct crypto_aead *child = ctx->child;
if (keylen < 4)
return -EINVAL;
keylen -= 4;
memcpy(ctx->nonce, key + keylen, 4);
crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
CRYPTO_TFM_REQ_MASK);
return crypto_aead_setkey(child, key, keylen);
}
static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
unsigned int authsize)
{
struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
if (authsize != 16)
return -EINVAL;
return crypto_aead_setauthsize(ctx->child, authsize);
}
static int crypto_rfc4543_crypt(struct aead_request *req, bool enc)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req);
struct aead_request *subreq = &rctx->subreq;
unsigned int authsize = crypto_aead_authsize(aead);
u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
crypto_aead_alignmask(ctx->child) + 1);
int err;
if (req->src != req->dst) {
err = crypto_rfc4543_copy_src_to_dst(req, enc);
if (err)
return err;
}
memcpy(iv, ctx->nonce, 4);
memcpy(iv + 4, req->iv, 8);
aead_request_set_tfm(subreq, ctx->child);
aead_request_set_callback(subreq, req->base.flags,
req->base.complete, req->base.data);
aead_request_set_crypt(subreq, req->src, req->dst,
enc ? 0 : authsize, iv);
aead_request_set_ad(subreq, req->assoclen + req->cryptlen -
subreq->cryptlen);
return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq);
}
static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int nbytes = req->assoclen + req->cryptlen -
(enc ? 0 : authsize);
SYNC_SKCIPHER_REQUEST_ON_STACK(nreq, ctx->null);
skcipher_request_set_sync_tfm(nreq, ctx->null);
skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL);
skcipher_request_set_crypt(nreq, req->src, req->dst, nbytes, NULL);
return crypto_skcipher_encrypt(nreq);
}