1/*
2 * GCM: Galois/Counter Mode.
3 *
4 * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published
8 * by the Free Software Foundation.
9 */
10
11#include <crypto/gf128mul.h>
12#include <crypto/internal/aead.h>
13#include <crypto/internal/skcipher.h>
14#include <crypto/internal/hash.h>
15#include <crypto/null.h>
16#include <crypto/scatterwalk.h>
17#include <crypto/gcm.h>
18#include <crypto/hash.h>
19#include "internal.h"
20#include <linux/err.h>
21#include <linux/init.h>
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/slab.h>
25
26struct gcm_instance_ctx {
27 struct crypto_skcipher_spawn ctr;
28 struct crypto_ahash_spawn ghash;
29};
30
31struct crypto_gcm_ctx {
32 struct crypto_skcipher *ctr;
33 struct crypto_ahash *ghash;
34};
35
36struct crypto_rfc4106_ctx {
37 struct crypto_aead *child;
38 u8 nonce[4];
39};
40
41struct crypto_rfc4106_req_ctx {
42 struct scatterlist src[3];
43 struct scatterlist dst[3];
44 struct aead_request subreq;
45};
46
47struct crypto_rfc4543_instance_ctx {
48 struct crypto_aead_spawn aead;
49};
50
51struct crypto_rfc4543_ctx {
52 struct crypto_aead *child;
53 struct crypto_sync_skcipher *null;
54 u8 nonce[4];
55};
56
57struct crypto_rfc4543_req_ctx {
58 struct aead_request subreq;
59};
60
61struct crypto_gcm_ghash_ctx {
62 unsigned int cryptlen;
63 struct scatterlist *src;
64 int (*complete)(struct aead_request *req, u32 flags);
65};
66
67struct crypto_gcm_req_priv_ctx {
68 u8 iv[16];
69 u8 auth_tag[16];
70 u8 iauth_tag[16];
71 struct scatterlist src[3];
72 struct scatterlist dst[3];
73 struct scatterlist sg;
74 struct crypto_gcm_ghash_ctx ghash_ctx;
75 union {
76 struct ahash_request ahreq;
77 struct skcipher_request skreq;
78 } u;
79};
80
81static struct {
82 u8 buf[16];
83 struct scatterlist sg;
84} *gcm_zeroes;
85
86static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc);
87
88static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
89 struct aead_request *req)
90{
91 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
92
93 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
94}
95
96static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
97 unsigned int keylen)
98{
99 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
100 struct crypto_ahash *ghash = ctx->ghash;
101 struct crypto_skcipher *ctr = ctx->ctr;
102 struct {
103 be128 hash;
104 u8 iv[16];
105
106 struct crypto_wait wait;
107
108 struct scatterlist sg[1];
109 struct skcipher_request req;
110 } *data;
111 int err;
112
113 crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
114 crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
115 CRYPTO_TFM_REQ_MASK);
116 err = crypto_skcipher_setkey(ctr, key, keylen);
117 crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctr) &
118 CRYPTO_TFM_RES_MASK);
119 if (err)
120 return err;
121
122 data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr),
123 GFP_KERNEL);
124 if (!data)
125 return -ENOMEM;
126
127 crypto_init_wait(&data->wait);
128 sg_init_one(data->sg, &data->hash, sizeof(data->hash));
129 skcipher_request_set_tfm(&data->req, ctr);
130 skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
131 CRYPTO_TFM_REQ_MAY_BACKLOG,
132 crypto_req_done,
133 &data->wait);
134 skcipher_request_set_crypt(&data->req, data->sg, data->sg,
135 sizeof(data->hash), data->iv);
136
137 err = crypto_wait_req(crypto_skcipher_encrypt(&data->req),
138 &data->wait);
139
140 if (err)
141 goto out;
142
143 crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK);
144 crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) &
145 CRYPTO_TFM_REQ_MASK);
146 err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128));
147 crypto_aead_set_flags(aead, crypto_ahash_get_flags(ghash) &
148 CRYPTO_TFM_RES_MASK);
149
150out:
151 kzfree(data);
152 return err;
153}
154
155static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
156 unsigned int authsize)
157{
158 switch (authsize) {
159 case 4:
160 case 8:
161 case 12:
162 case 13:
163 case 14:
164 case 15:
165 case 16:
166 break;
167 default:
168 return -EINVAL;
169 }
170
171 return 0;
172}
173
174static void crypto_gcm_init_common(struct aead_request *req)
175{
176 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
177 __be32 counter = cpu_to_be32(1);
178 struct scatterlist *sg;
179
180 memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
181 memcpy(pctx->iv, req->iv, GCM_AES_IV_SIZE);
182 memcpy(pctx->iv + GCM_AES_IV_SIZE, &counter, 4);
183
184 sg_init_table(pctx->src, 3);
185 sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
186 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
187 if (sg != pctx->src + 1)
188 sg_chain(pctx->src, 2, sg);
189
190 if (req->src != req->dst) {
191 sg_init_table(pctx->dst, 3);
192 sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag));
193 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
194 if (sg != pctx->dst + 1)
195 sg_chain(pctx->dst, 2, sg);
196 }
197}
198
199static void crypto_gcm_init_crypt(struct aead_request *req,
200 unsigned int cryptlen)
201{
202 struct crypto_aead *aead = crypto_aead_reqtfm(req);
203 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
204 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
205 struct skcipher_request *skreq = &pctx->u.skreq;
206 struct scatterlist *dst;
207
208 dst = req->src == req->dst ? pctx->src : pctx->dst;
209
210 skcipher_request_set_tfm(skreq, ctx->ctr);
211 skcipher_request_set_crypt(skreq, pctx->src, dst,
212 cryptlen + sizeof(pctx->auth_tag),
213 pctx->iv);
214}
215
216static inline unsigned int gcm_remain(unsigned int len)
217{
218 len &= 0xfU;
219 return len ? 16 - len : 0;
220}
221
222static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
223
224static int gcm_hash_update(struct aead_request *req,
225 crypto_completion_t compl,
226 struct scatterlist *src,
227 unsigned int len, u32 flags)
228{
229 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
230 struct ahash_request *ahreq = &pctx->u.ahreq;
231
232 ahash_request_set_callback(ahreq, flags, compl, req);
233 ahash_request_set_crypt(ahreq, src, NULL, len);
234
235 return crypto_ahash_update(ahreq);
236}
237
238static int gcm_hash_remain(struct aead_request *req,
239 unsigned int remain,
240 crypto_completion_t compl, u32 flags)
241{
242 return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags);
243}
244
245static int gcm_hash_len(struct aead_request *req, u32 flags)
246{
247 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
248 struct ahash_request *ahreq = &pctx->u.ahreq;
249 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
250 be128 lengths;
251
252 lengths.a = cpu_to_be64(req->assoclen * 8);
253 lengths.b = cpu_to_be64(gctx->cryptlen * 8);
254 memcpy(pctx->iauth_tag, &lengths, 16);
255 sg_init_one(&pctx->sg, pctx->iauth_tag, 16);
256 ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req);
257 ahash_request_set_crypt(ahreq, &pctx->sg,
258 pctx->iauth_tag, sizeof(lengths));
259
260 return crypto_ahash_finup(ahreq);
261}
262
263static int gcm_hash_len_continue(struct aead_request *req, u32 flags)
264{
265 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
266 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
267
268 return gctx->complete(req, flags);
269}
270
271static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
272{
273 struct aead_request *req = areq->data;
274
275 if (err)
276 goto out;
277
278 err = gcm_hash_len_continue(req, 0);
279 if (err == -EINPROGRESS)
280 return;
281
282out:
283 aead_request_complete(req, err);
284}
285
286static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags)
287{
288 return gcm_hash_len(req, flags) ?:
289 gcm_hash_len_continue(req, flags);
290}
291
292static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
293 int err)
294{
295 struct aead_request *req = areq->data;
296
297 if (err)
298 goto out;
299
300 err = gcm_hash_crypt_remain_continue(req, 0);
301 if (err == -EINPROGRESS)
302 return;
303
304out:
305 aead_request_complete(req, err);
306}
307
308static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags)
309{
310 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
311 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
312 unsigned int remain;
313
314 remain = gcm_remain(gctx->cryptlen);
315 if (remain)
316 return gcm_hash_remain(req, remain,
317 gcm_hash_crypt_remain_done, flags) ?:
318 gcm_hash_crypt_remain_continue(req, flags);
319
320 return gcm_hash_crypt_remain_continue(req, flags);
321}
322
323static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
324{
325 struct aead_request *req = areq->data;
326
327 if (err)
328 goto out;
329
330 err = gcm_hash_crypt_continue(req, 0);
331 if (err == -EINPROGRESS)
332 return;
333
334out:
335 aead_request_complete(req, err);
336}
337
338static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags)
339{
340 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
341 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
342
343 if (gctx->cryptlen)
344 return gcm_hash_update(req, gcm_hash_crypt_done,
345 gctx->src, gctx->cryptlen, flags) ?:
346 gcm_hash_crypt_continue(req, flags);
347
348 return gcm_hash_crypt_remain_continue(req, flags);
349}
350
351static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
352 int err)
353{
354 struct aead_request *req = areq->data;
355
356 if (err)
357 goto out;
358
359 err = gcm_hash_assoc_remain_continue(req, 0);
360 if (err == -EINPROGRESS)
361 return;
362
363out:
364 aead_request_complete(req, err);
365}
366
367static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags)
368{
369 unsigned int remain;
370
371 remain = gcm_remain(req->assoclen);
372 if (remain)
373 return gcm_hash_remain(req, remain,
374 gcm_hash_assoc_remain_done, flags) ?:
375 gcm_hash_assoc_remain_continue(req, flags);
376
377 return gcm_hash_assoc_remain_continue(req, flags);
378}
379
380static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
381{
382 struct aead_request *req = areq->data;
383
384 if (err)
385 goto out;
386
387 err = gcm_hash_assoc_continue(req, 0);
388 if (err == -EINPROGRESS)
389 return;
390
391out:
392 aead_request_complete(req, err);
393}
394
395static int gcm_hash_init_continue(struct aead_request *req, u32 flags)
396{
397 if (req->assoclen)
398 return gcm_hash_update(req, gcm_hash_assoc_done,
399 req->src, req->assoclen, flags) ?:
400 gcm_hash_assoc_continue(req, flags);
401
402 return gcm_hash_assoc_remain_continue(req, flags);
403}
404
405static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
406{
407 struct aead_request *req = areq->data;
408
409 if (err)
410 goto out;
411
412 err = gcm_hash_init_continue(req, 0);
413 if (err == -EINPROGRESS)
414 return;
415
416out:
417 aead_request_complete(req, err);
418}
419
420static int gcm_hash(struct aead_request *req, u32 flags)
421{
422 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
423 struct ahash_request *ahreq = &pctx->u.ahreq;
424 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
425
426 ahash_request_set_tfm(ahreq, ctx->ghash);
427
428 ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req);
429 return crypto_ahash_init(ahreq) ?:
430 gcm_hash_init_continue(req, flags);
431}
432
433static int gcm_enc_copy_hash(struct aead_request *req, u32 flags)
434{
435 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
436 struct crypto_aead *aead = crypto_aead_reqtfm(req);
437 u8 *auth_tag = pctx->auth_tag;
438
439 crypto_xor(auth_tag, pctx->iauth_tag, 16);
440 scatterwalk_map_and_copy(auth_tag, req->dst,
441 req->assoclen + req->cryptlen,
442 crypto_aead_authsize(aead), 1);
443 return 0;
444}
445
446static int gcm_encrypt_continue(struct aead_request *req, u32 flags)
447{
448 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
449 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
450
451 gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
452 gctx->cryptlen = req->cryptlen;
453 gctx->complete = gcm_enc_copy_hash;
454
455 return gcm_hash(req, flags);
456}
457
458static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
459{
460 struct aead_request *req = areq->data;
461
462 if (err)
463 goto out;
464
465 err = gcm_encrypt_continue(req, 0);
466 if (err == -EINPROGRESS)
467 return;
468
469out:
470 aead_request_complete(req, err);
471}
472
473static int crypto_gcm_encrypt(struct aead_request *req)
474{
475 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
476 struct skcipher_request *skreq = &pctx->u.skreq;
477 u32 flags = aead_request_flags(req);
478
479 crypto_gcm_init_common(req);
480 crypto_gcm_init_crypt(req, req->cryptlen);
481 skcipher_request_set_callback(skreq, flags, gcm_encrypt_done, req);
482
483 return crypto_skcipher_encrypt(skreq) ?:
484 gcm_encrypt_continue(req, flags);
485}
486
487static int crypto_gcm_verify(struct aead_request *req)
488{
489 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
490 struct crypto_aead *aead = crypto_aead_reqtfm(req);
491 u8 *auth_tag = pctx->auth_tag;
492 u8 *iauth_tag = pctx->iauth_tag;
493 unsigned int authsize = crypto_aead_authsize(aead);
494 unsigned int cryptlen = req->cryptlen - authsize;
495
496 crypto_xor(auth_tag, iauth_tag, 16);
497 scatterwalk_map_and_copy(iauth_tag, req->src,
498 req->assoclen + cryptlen, authsize, 0);
499 return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
500}
501
502static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
503{
504 struct aead_request *req = areq->data;
505
506 if (!err)
507 err = crypto_gcm_verify(req);
508
509 aead_request_complete(req, err);
510}
511
512static int gcm_dec_hash_continue(struct aead_request *req, u32 flags)
513{
514 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
515 struct skcipher_request *skreq = &pctx->u.skreq;
516 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
517
518 crypto_gcm_init_crypt(req, gctx->cryptlen);
519 skcipher_request_set_callback(skreq, flags, gcm_decrypt_done, req);
520 return crypto_skcipher_decrypt(skreq) ?: crypto_gcm_verify(req);
521}
522
523static int crypto_gcm_decrypt(struct aead_request *req)
524{
525 struct crypto_aead *aead = crypto_aead_reqtfm(req);
526 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
527 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
528 unsigned int authsize = crypto_aead_authsize(aead);
529 unsigned int cryptlen = req->cryptlen;
530 u32 flags = aead_request_flags(req);
531
532 cryptlen -= authsize;
533
534 crypto_gcm_init_common(req);
535
536 gctx->src = sg_next(pctx->src);
537 gctx->cryptlen = cryptlen;
538 gctx->complete = gcm_dec_hash_continue;
539
540 return gcm_hash(req, flags);
541}
542
543static int crypto_gcm_init_tfm(struct crypto_aead *tfm)
544{
545 struct aead_instance *inst = aead_alg_instance(tfm);
546 struct gcm_instance_ctx *ictx = aead_instance_ctx(inst);
547 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
548 struct crypto_skcipher *ctr;
549 struct crypto_ahash *ghash;
550 unsigned long align;
551 int err;
552
553 ghash = crypto_spawn_ahash(&ictx->ghash);
554 if (IS_ERR(ghash))
555 return PTR_ERR(ghash);
556
557 ctr = crypto_spawn_skcipher(&ictx->ctr);
558 err = PTR_ERR(ctr);
559 if (IS_ERR(ctr))
560 goto err_free_hash;
561
562 ctx->ctr = ctr;
563 ctx->ghash = ghash;
564
565 align = crypto_aead_alignmask(tfm);
566 align &= ~(crypto_tfm_ctx_alignment() - 1);
567 crypto_aead_set_reqsize(tfm,
568 align + offsetof(struct crypto_gcm_req_priv_ctx, u) +
569 max(sizeof(struct skcipher_request) +
570 crypto_skcipher_reqsize(ctr),
571 sizeof(struct ahash_request) +
572 crypto_ahash_reqsize(ghash)));
573
574 return 0;
575
576err_free_hash:
577 crypto_free_ahash(ghash);
578 return err;
579}
580
581static void crypto_gcm_exit_tfm(struct crypto_aead *tfm)
582{
583 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
584
585 crypto_free_ahash(ctx->ghash);
586 crypto_free_skcipher(ctx->ctr);
587}
588
589static void crypto_gcm_free(struct aead_instance *inst)
590{
591 struct gcm_instance_ctx *ctx = aead_instance_ctx(inst);
592
593 crypto_drop_skcipher(&ctx->ctr);
594 crypto_drop_ahash(&ctx->ghash);
595 kfree(inst);
596}
597
598static int crypto_gcm_create_common(struct crypto_template *tmpl,
599 struct rtattr **tb,
600 const char *full_name,
601 const char *ctr_name,
602 const char *ghash_name)
603{
604 struct crypto_attr_type *algt;
605 struct aead_instance *inst;
606 struct skcipher_alg *ctr;
607 struct crypto_alg *ghash_alg;
608 struct hash_alg_common *ghash;
609 struct gcm_instance_ctx *ctx;
610 int err;
611
612 algt = crypto_get_attr_type(tb);
613 if (IS_ERR(algt))
614 return PTR_ERR(algt);
615
616 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
617 return -EINVAL;
618
619 ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type,
620 CRYPTO_ALG_TYPE_HASH,
621 CRYPTO_ALG_TYPE_AHASH_MASK |
622 crypto_requires_sync(algt->type,
623 algt->mask));
624 if (IS_ERR(ghash_alg))
625 return PTR_ERR(ghash_alg);
626
627 ghash = __crypto_hash_alg_common(ghash_alg);
628
629 err = -ENOMEM;
630 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
631 if (!inst)
632 goto out_put_ghash;
633
634 ctx = aead_instance_ctx(inst);
635 err = crypto_init_ahash_spawn(&ctx->ghash, ghash,
636 aead_crypto_instance(inst));
637 if (err)
638 goto err_free_inst;
639
640 err = -EINVAL;
641 if (ghash->digestsize != 16)
642 goto err_drop_ghash;
643
644 crypto_set_skcipher_spawn(&ctx->ctr, aead_crypto_instance(inst));
645 err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0,
646 crypto_requires_sync(algt->type,
647 algt->mask));
648 if (err)
649 goto err_drop_ghash;
650
651 ctr = crypto_spawn_skcipher_alg(&ctx->ctr);
652
653 /* We only support 16-byte blocks. */
654 err = -EINVAL;
655 if (crypto_skcipher_alg_ivsize(ctr) != 16)
656 goto out_put_ctr;
657
658 /* Not a stream cipher? */
659 if (ctr->base.cra_blocksize != 1)
660 goto out_put_ctr;
661
662 err = -ENAMETOOLONG;
663 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
664 "gcm_base(%s,%s)", ctr->base.cra_driver_name,
665 ghash_alg->cra_driver_name) >=
666 CRYPTO_MAX_ALG_NAME)
667 goto out_put_ctr;
668
669 memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
670
671 inst->alg.base.cra_flags = (ghash->base.cra_flags |
672 ctr->base.cra_flags) & CRYPTO_ALG_ASYNC;
673 inst->alg.base.cra_priority = (ghash->base.cra_priority +
674 ctr->base.cra_priority) / 2;
675 inst->alg.base.cra_blocksize = 1;
676 inst->alg.base.cra_alignmask = ghash->base.cra_alignmask |
677 ctr->base.cra_alignmask;
678 inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx);
679 inst->alg.ivsize = GCM_AES_IV_SIZE;
680 inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
681 inst->alg.maxauthsize = 16;
682 inst->alg.init = crypto_gcm_init_tfm;
683 inst->alg.exit = crypto_gcm_exit_tfm;
684 inst->alg.setkey = crypto_gcm_setkey;
685 inst->alg.setauthsize = crypto_gcm_setauthsize;
686 inst->alg.encrypt = crypto_gcm_encrypt;
687 inst->alg.decrypt = crypto_gcm_decrypt;
688
689 inst->free = crypto_gcm_free;
690
691 err = aead_register_instance(tmpl, inst);
692 if (err)
693 goto out_put_ctr;
694
695out_put_ghash:
696 crypto_mod_put(ghash_alg);
697 return err;
698
699out_put_ctr:
700 crypto_drop_skcipher(&ctx->ctr);
701err_drop_ghash:
702 crypto_drop_ahash(&ctx->ghash);
703err_free_inst:
704 kfree(inst);
705 goto out_put_ghash;
706}
707
708static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb)
709{
710 const char *cipher_name;
711 char ctr_name[CRYPTO_MAX_ALG_NAME];
712 char full_name[CRYPTO_MAX_ALG_NAME];
713
714 cipher_name = crypto_attr_alg_name(tb[1]);
715 if (IS_ERR(cipher_name))
716 return PTR_ERR(cipher_name);
717
718 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
719 CRYPTO_MAX_ALG_NAME)
720 return -ENAMETOOLONG;
721
722 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm(%s)", cipher_name) >=
723 CRYPTO_MAX_ALG_NAME)
724 return -ENAMETOOLONG;
725
726 return crypto_gcm_create_common(tmpl, tb, full_name,
727 ctr_name, "ghash");
728}
729
730static int crypto_gcm_base_create(struct crypto_template *tmpl,
731 struct rtattr **tb)
732{
733 const char *ctr_name;
734 const char *ghash_name;
735 char full_name[CRYPTO_MAX_ALG_NAME];
736
737 ctr_name = crypto_attr_alg_name(tb[1]);
738 if (IS_ERR(ctr_name))
739 return PTR_ERR(ctr_name);
740
741 ghash_name = crypto_attr_alg_name(tb[2]);
742 if (IS_ERR(ghash_name))
743 return PTR_ERR(ghash_name);
744
745 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)",
746 ctr_name, ghash_name) >= CRYPTO_MAX_ALG_NAME)
747 return -ENAMETOOLONG;
748
749 return crypto_gcm_create_common(tmpl, tb, full_name,
750 ctr_name, ghash_name);
751}
752
753static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
754 unsigned int keylen)
755{
756 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
757 struct crypto_aead *child = ctx->child;
758 int err;
759
760 if (keylen < 4)
761 return -EINVAL;
762
763 keylen -= 4;
764 memcpy(ctx->nonce, key + keylen, 4);
765
766 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
767 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
768 CRYPTO_TFM_REQ_MASK);
769 err = crypto_aead_setkey(child, key, keylen);
770 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
771 CRYPTO_TFM_RES_MASK);
772
773 return err;
774}
775
776static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
777 unsigned int authsize)
778{
779 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
780
781 switch (authsize) {
782 case 8:
783 case 12:
784 case 16:
785 break;
786 default:
787 return -EINVAL;
788 }
789
790 return crypto_aead_setauthsize(ctx->child, authsize);
791}
792
793static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
794{
795 struct crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req);
796 struct crypto_aead *aead = crypto_aead_reqtfm(req);
797 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead);
798 struct aead_request *subreq = &rctx->subreq;
799 struct crypto_aead *child = ctx->child;
800 struct scatterlist *sg;
801 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
802 crypto_aead_alignmask(child) + 1);
803
804 scatterwalk_map_and_copy(iv + GCM_AES_IV_SIZE, req->src, 0, req->assoclen - 8, 0);
805
806 memcpy(iv, ctx->nonce, 4);
807 memcpy(iv + 4, req->iv, 8);
808
809 sg_init_table(rctx->src, 3);
810 sg_set_buf(rctx->src, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
811 sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
812 if (sg != rctx->src + 1)
813 sg_chain(rctx->src, 2, sg);
814
815 if (req->src != req->dst) {
816 sg_init_table(rctx->dst, 3);
817 sg_set_buf(rctx->dst, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
818 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
819 if (sg != rctx->dst + 1)
820 sg_chain(rctx->dst, 2, sg);
821 }
822
823 aead_request_set_tfm(subreq, child);
824 aead_request_set_callback(subreq, req->base.flags, req->base.complete,
825 req->base.data);
826 aead_request_set_crypt(subreq, rctx->src,
827 req->src == req->dst ? rctx->src : rctx->dst,
828 req->cryptlen, iv);
829 aead_request_set_ad(subreq, req->assoclen - 8);
830
831 return subreq;
832}
833
834static int crypto_rfc4106_encrypt(struct aead_request *req)
835{
836 if (req->assoclen != 16 && req->assoclen != 20)
837 return -EINVAL;
838
839 req = crypto_rfc4106_crypt(req);
840
841 return crypto_aead_encrypt(req);
842}
843
844static int crypto_rfc4106_decrypt(struct aead_request *req)
845{
846 if (req->assoclen != 16 && req->assoclen != 20)
847 return -EINVAL;
848
849 req = crypto_rfc4106_crypt(req);
850
851 return crypto_aead_decrypt(req);
852}
853
854static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm)
855{
856 struct aead_instance *inst = aead_alg_instance(tfm);
857 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
858 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
859 struct crypto_aead *aead;
860 unsigned long align;
861
862 aead = crypto_spawn_aead(spawn);
863 if (IS_ERR(aead))
864 return PTR_ERR(aead);
865
866 ctx->child = aead;
867
868 align = crypto_aead_alignmask(aead);
869 align &= ~(crypto_tfm_ctx_alignment() - 1);
870 crypto_aead_set_reqsize(
871 tfm,
872 sizeof(struct crypto_rfc4106_req_ctx) +
873 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
874 align + 24);
875
876 return 0;
877}
878
879static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm)
880{
881 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
882
883 crypto_free_aead(ctx->child);
884}
885
886static void crypto_rfc4106_free(struct aead_instance *inst)
887{
888 crypto_drop_aead(aead_instance_ctx(inst));
889 kfree(inst);
890}
891
892static int crypto_rfc4106_create(struct crypto_template *tmpl,
893 struct rtattr **tb)
894{
895 struct crypto_attr_type *algt;
896 struct aead_instance *inst;
897 struct crypto_aead_spawn *spawn;
898 struct aead_alg *alg;
899 const char *ccm_name;
900 int err;
901
902 algt = crypto_get_attr_type(tb);
903 if (IS_ERR(algt))
904 return PTR_ERR(algt);
905
906 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
907 return -EINVAL;
908
909 ccm_name = crypto_attr_alg_name(tb[1]);
910 if (IS_ERR(ccm_name))
911 return PTR_ERR(ccm_name);
912
913 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
914 if (!inst)
915 return -ENOMEM;
916
917 spawn = aead_instance_ctx(inst);
918 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
919 err = crypto_grab_aead(spawn, ccm_name, 0,
920 crypto_requires_sync(algt->type, algt->mask));
921 if (err)
922 goto out_free_inst;
923
924 alg = crypto_spawn_aead_alg(spawn);
925
926 err = -EINVAL;
927
928 /* Underlying IV size must be 12. */
929 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
930 goto out_drop_alg;
931
932 /* Not a stream cipher? */
933 if (alg->base.cra_blocksize != 1)
934 goto out_drop_alg;
935
936 err = -ENAMETOOLONG;
937 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
938 "rfc4106(%s)", alg->base.cra_name) >=
939 CRYPTO_MAX_ALG_NAME ||
940 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
941 "rfc4106(%s)", alg->base.cra_driver_name) >=
942 CRYPTO_MAX_ALG_NAME)
943 goto out_drop_alg;
944
945 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
946 inst->alg.base.cra_priority = alg->base.cra_priority;
947 inst->alg.base.cra_blocksize = 1;
948 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
949
950 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
951
952 inst->alg.ivsize = GCM_RFC4106_IV_SIZE;
953 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
954 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
955
956 inst->alg.init = crypto_rfc4106_init_tfm;
957 inst->alg.exit = crypto_rfc4106_exit_tfm;
958
959 inst->alg.setkey = crypto_rfc4106_setkey;
960 inst->alg.setauthsize = crypto_rfc4106_setauthsize;
961 inst->alg.encrypt = crypto_rfc4106_encrypt;
962 inst->alg.decrypt = crypto_rfc4106_decrypt;
963
964 inst->free = crypto_rfc4106_free;
965
966 err = aead_register_instance(tmpl, inst);
967 if (err)
968 goto out_drop_alg;
969
970out:
971 return err;
972
973out_drop_alg:
974 crypto_drop_aead(spawn);
975out_free_inst:
976 kfree(inst);
977 goto out;
978}
979
980static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
981 unsigned int keylen)
982{
983 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
984 struct crypto_aead *child = ctx->child;
985 int err;
986
987 if (keylen < 4)
988 return -EINVAL;
989
990 keylen -= 4;
991 memcpy(ctx->nonce, key + keylen, 4);
992
993 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
994 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
995 CRYPTO_TFM_REQ_MASK);
996 err = crypto_aead_setkey(child, key, keylen);
997 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
998 CRYPTO_TFM_RES_MASK);
999
1000 return err;
1001}
1002
1003static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
1004 unsigned int authsize)
1005{
1006 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
1007
1008 if (authsize != 16)
1009 return -EINVAL;
1010
1011 return crypto_aead_setauthsize(ctx->child, authsize);
1012}
1013
1014static int crypto_rfc4543_crypt(struct aead_request *req, bool enc)
1015{
1016 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1017 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1018 struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req);
1019 struct aead_request *subreq = &rctx->subreq;
1020 unsigned int authsize = crypto_aead_authsize(aead);
1021 u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
1022 crypto_aead_alignmask(ctx->child) + 1);
1023 int err;
1024
1025 if (req->src != req->dst) {
1026 err = crypto_rfc4543_copy_src_to_dst(req, enc);
1027 if (err)
1028 return err;
1029 }
1030
1031 memcpy(iv, ctx->nonce, 4);
1032 memcpy(iv + 4, req->iv, 8);
1033
1034 aead_request_set_tfm(subreq, ctx->child);
1035 aead_request_set_callback(subreq, req->base.flags,
1036 req->base.complete, req->base.data);
1037 aead_request_set_crypt(subreq, req->src, req->dst,
1038 enc ? 0 : authsize, iv);
1039 aead_request_set_ad(subreq, req->assoclen + req->cryptlen -
1040 subreq->cryptlen);
1041
1042 return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq);
1043}
1044
1045static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
1046{
1047 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1048 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1049 unsigned int authsize = crypto_aead_authsize(aead);
1050 unsigned int nbytes = req->assoclen + req->cryptlen -
1051 (enc ? 0 : authsize);
1052 SYNC_SKCIPHER_REQUEST_ON_STACK(nreq, ctx->null);
1053
1054 skcipher_request_set_sync_tfm(nreq, ctx->null);
1055 skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL);
1056 skcipher_request_set_crypt(nreq, req->src, req->dst, nbytes, NULL);
1057
1058 return crypto_skcipher_encrypt(nreq);
1059}
1060
1061static int crypto_rfc4543_encrypt(struct aead_request *req)
1062{
1063 return crypto_rfc4543_crypt(req, true);
1064}
1065
1066static int crypto_rfc4543_decrypt(struct aead_request *req)
1067{
1068 return crypto_rfc4543_crypt(req, false);
1069}
1070
1071static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm)
1072{
1073 struct aead_instance *inst = aead_alg_instance(tfm);
1074 struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst);
1075 struct crypto_aead_spawn *spawn = &ictx->aead;
1076 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1077 struct crypto_aead *aead;
1078 struct crypto_sync_skcipher *null;
1079 unsigned long align;
1080 int err = 0;
1081
1082 aead = crypto_spawn_aead(spawn);
1083 if (IS_ERR(aead))
1084 return PTR_ERR(aead);
1085
1086 null = crypto_get_default_null_skcipher();
1087 err = PTR_ERR(null);
1088 if (IS_ERR(null))
1089 goto err_free_aead;
1090
1091 ctx->child = aead;
1092 ctx->null = null;
1093
1094 align = crypto_aead_alignmask(aead);
1095 align &= ~(crypto_tfm_ctx_alignment() - 1);
1096 crypto_aead_set_reqsize(
1097 tfm,
1098 sizeof(struct crypto_rfc4543_req_ctx) +
1099 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
1100 align + GCM_AES_IV_SIZE);
1101
1102 return 0;
1103
1104err_free_aead:
1105 crypto_free_aead(aead);
1106 return err;
1107}
1108
1109static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm)
1110{
1111 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1112
1113 crypto_free_aead(ctx->child);
1114 crypto_put_default_null_skcipher();
1115}
1116
1117static void crypto_rfc4543_free(struct aead_instance *inst)
1118{
1119 struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst);
1120
1121 crypto_drop_aead(&ctx->aead);
1122
1123 kfree(inst);
1124}
1125
1126static int crypto_rfc4543_create(struct crypto_template *tmpl,
1127 struct rtattr **tb)
1128{
1129 struct crypto_attr_type *algt;
1130 struct aead_instance *inst;
1131 struct crypto_aead_spawn *spawn;
1132 struct aead_alg *alg;
1133 struct crypto_rfc4543_instance_ctx *ctx;
1134 const char *ccm_name;
1135 int err;
1136
1137 algt = crypto_get_attr_type(tb);
1138 if (IS_ERR(algt))
1139 return PTR_ERR(algt);
1140
1141 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
1142 return -EINVAL;
1143
1144 ccm_name = crypto_attr_alg_name(tb[1]);
1145 if (IS_ERR(ccm_name))
1146 return PTR_ERR(ccm_name);
1147
1148 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
1149 if (!inst)
1150 return -ENOMEM;
1151
1152 ctx = aead_instance_ctx(inst);
1153 spawn = &ctx->aead;
1154 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
1155 err = crypto_grab_aead(spawn, ccm_name, 0,
1156 crypto_requires_sync(algt->type, algt->mask));
1157 if (err)
1158 goto out_free_inst;
1159
1160 alg = crypto_spawn_aead_alg(spawn);
1161
1162 err = -EINVAL;
1163
1164 /* Underlying IV size must be 12. */
1165 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
1166 goto out_drop_alg;
1167
1168 /* Not a stream cipher? */
1169 if (alg->base.cra_blocksize != 1)
1170 goto out_drop_alg;
1171
1172 err = -ENAMETOOLONG;
1173 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
1174 "rfc4543(%s)", alg->base.cra_name) >=
1175 CRYPTO_MAX_ALG_NAME ||
1176 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
1177 "rfc4543(%s)", alg->base.cra_driver_name) >=
1178 CRYPTO_MAX_ALG_NAME)
1179 goto out_drop_alg;
1180
1181 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
1182 inst->alg.base.cra_priority = alg->base.cra_priority;
1183 inst->alg.base.cra_blocksize = 1;
1184 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
1185
1186 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx);
1187
1188 inst->alg.ivsize = GCM_RFC4543_IV_SIZE;
1189 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
1190 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
1191
1192 inst->alg.init = crypto_rfc4543_init_tfm;
1193 inst->alg.exit = crypto_rfc4543_exit_tfm;
1194
1195 inst->alg.setkey = crypto_rfc4543_setkey;
1196 inst->alg.setauthsize = crypto_rfc4543_setauthsize;
1197 inst->alg.encrypt = crypto_rfc4543_encrypt;
1198 inst->alg.decrypt = crypto_rfc4543_decrypt;
1199
1200 inst->free = crypto_rfc4543_free,
1201
1202 err = aead_register_instance(tmpl, inst);
1203 if (err)
1204 goto out_drop_alg;
1205
1206out:
1207 return err;
1208
1209out_drop_alg:
1210 crypto_drop_aead(spawn);
1211out_free_inst:
1212 kfree(inst);
1213 goto out;
1214}
1215
1216static struct crypto_template crypto_gcm_tmpls[] = {
1217 {
1218 .name = "gcm_base",
1219 .create = crypto_gcm_base_create,
1220 .module = THIS_MODULE,
1221 }, {
1222 .name = "gcm",
1223 .create = crypto_gcm_create,
1224 .module = THIS_MODULE,
1225 }, {
1226 .name = "rfc4106",
1227 .create = crypto_rfc4106_create,
1228 .module = THIS_MODULE,
1229 }, {
1230 .name = "rfc4543",
1231 .create = crypto_rfc4543_create,
1232 .module = THIS_MODULE,
1233 },
1234};
1235
1236static int __init crypto_gcm_module_init(void)
1237{
1238 int err;
1239
1240 gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL);
1241 if (!gcm_zeroes)
1242 return -ENOMEM;
1243
1244 sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf));
1245
1246 err = crypto_register_templates(crypto_gcm_tmpls,
1247 ARRAY_SIZE(crypto_gcm_tmpls));
1248 if (err)
1249 kfree(gcm_zeroes);
1250
1251 return err;
1252}
1253
1254static void __exit crypto_gcm_module_exit(void)
1255{
1256 kfree(gcm_zeroes);
1257 crypto_unregister_templates(crypto_gcm_tmpls,
1258 ARRAY_SIZE(crypto_gcm_tmpls));
1259}
1260
1261module_init(crypto_gcm_module_init);
1262module_exit(crypto_gcm_module_exit);
1263
1264MODULE_LICENSE("GPL");
1265MODULE_DESCRIPTION("Galois/Counter Mode");
1266MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
1267MODULE_ALIAS_CRYPTO("gcm_base");
1268MODULE_ALIAS_CRYPTO("rfc4106");
1269MODULE_ALIAS_CRYPTO("rfc4543");
1270MODULE_ALIAS_CRYPTO("gcm");
1271