Root/crypto/authenc.c

1/*
2 * Authenc: Simple AEAD wrapper for IPsec
3 *
4 * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
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 as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
9 * any later version.
10 *
11 */
12
13#include <crypto/aead.h>
14#include <crypto/internal/hash.h>
15#include <crypto/internal/skcipher.h>
16#include <crypto/authenc.h>
17#include <crypto/scatterwalk.h>
18#include <linux/err.h>
19#include <linux/init.h>
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/rtnetlink.h>
23#include <linux/slab.h>
24#include <linux/spinlock.h>
25
26typedef u8 *(*authenc_ahash_t)(struct aead_request *req, unsigned int flags);
27
28struct authenc_instance_ctx {
29    struct crypto_ahash_spawn auth;
30    struct crypto_skcipher_spawn enc;
31};
32
33struct crypto_authenc_ctx {
34    unsigned int reqoff;
35    struct crypto_ahash *auth;
36    struct crypto_ablkcipher *enc;
37};
38
39struct authenc_request_ctx {
40    unsigned int cryptlen;
41    struct scatterlist *sg;
42    struct scatterlist asg[2];
43    struct scatterlist cipher[2];
44    crypto_completion_t complete;
45    crypto_completion_t update_complete;
46    char tail[];
47};
48
49static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
50                 unsigned int keylen)
51{
52    unsigned int authkeylen;
53    unsigned int enckeylen;
54    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
55    struct crypto_ahash *auth = ctx->auth;
56    struct crypto_ablkcipher *enc = ctx->enc;
57    struct rtattr *rta = (void *)key;
58    struct crypto_authenc_key_param *param;
59    int err = -EINVAL;
60
61    if (!RTA_OK(rta, keylen))
62        goto badkey;
63    if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM)
64        goto badkey;
65    if (RTA_PAYLOAD(rta) < sizeof(*param))
66        goto badkey;
67
68    param = RTA_DATA(rta);
69    enckeylen = be32_to_cpu(param->enckeylen);
70
71    key += RTA_ALIGN(rta->rta_len);
72    keylen -= RTA_ALIGN(rta->rta_len);
73
74    if (keylen < enckeylen)
75        goto badkey;
76
77    authkeylen = keylen - enckeylen;
78
79    crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
80    crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) &
81                    CRYPTO_TFM_REQ_MASK);
82    err = crypto_ahash_setkey(auth, key, authkeylen);
83    crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) &
84                       CRYPTO_TFM_RES_MASK);
85
86    if (err)
87        goto out;
88
89    crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
90    crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
91                     CRYPTO_TFM_REQ_MASK);
92    err = crypto_ablkcipher_setkey(enc, key + authkeylen, enckeylen);
93    crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) &
94                       CRYPTO_TFM_RES_MASK);
95
96out:
97    return err;
98
99badkey:
100    crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN);
101    goto out;
102}
103
104static void authenc_chain(struct scatterlist *head, struct scatterlist *sg,
105              int chain)
106{
107    if (chain) {
108        head->length += sg->length;
109        sg = scatterwalk_sg_next(sg);
110    }
111
112    if (sg)
113        scatterwalk_sg_chain(head, 2, sg);
114    else
115        sg_mark_end(head);
116}
117
118static void authenc_geniv_ahash_update_done(struct crypto_async_request *areq,
119                        int err)
120{
121    struct aead_request *req = areq->data;
122    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
123    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
124    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
125    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
126
127    if (err)
128        goto out;
129
130    ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
131                areq_ctx->cryptlen);
132    ahash_request_set_callback(ahreq, aead_request_flags(req) &
133                      CRYPTO_TFM_REQ_MAY_SLEEP,
134                   areq_ctx->complete, req);
135
136    err = crypto_ahash_finup(ahreq);
137    if (err)
138        goto out;
139
140    scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
141                 areq_ctx->cryptlen,
142                 crypto_aead_authsize(authenc), 1);
143
144out:
145    aead_request_complete(req, err);
146}
147
148static void authenc_geniv_ahash_done(struct crypto_async_request *areq, int err)
149{
150    struct aead_request *req = areq->data;
151    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
152    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
153    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
154    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
155
156    if (err)
157        goto out;
158
159    scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
160                 areq_ctx->cryptlen,
161                 crypto_aead_authsize(authenc), 1);
162
163out:
164    aead_request_complete(req, err);
165}
166
167static void authenc_verify_ahash_update_done(struct crypto_async_request *areq,
168                         int err)
169{
170    u8 *ihash;
171    unsigned int authsize;
172    struct ablkcipher_request *abreq;
173    struct aead_request *req = areq->data;
174    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
175    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
176    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
177    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
178
179    if (err)
180        goto out;
181
182    ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
183                areq_ctx->cryptlen);
184    ahash_request_set_callback(ahreq, aead_request_flags(req) &
185                      CRYPTO_TFM_REQ_MAY_SLEEP,
186                   areq_ctx->complete, req);
187
188    err = crypto_ahash_finup(ahreq);
189    if (err)
190        goto out;
191
192    authsize = crypto_aead_authsize(authenc);
193    ihash = ahreq->result + authsize;
194    scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
195                 authsize, 0);
196
197    err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG: 0;
198    if (err)
199        goto out;
200
201    abreq = aead_request_ctx(req);
202    ablkcipher_request_set_tfm(abreq, ctx->enc);
203    ablkcipher_request_set_callback(abreq, aead_request_flags(req),
204                    req->base.complete, req->base.data);
205    ablkcipher_request_set_crypt(abreq, req->src, req->dst,
206                     req->cryptlen, req->iv);
207
208    err = crypto_ablkcipher_decrypt(abreq);
209
210out:
211    aead_request_complete(req, err);
212}
213
214static void authenc_verify_ahash_done(struct crypto_async_request *areq,
215                      int err)
216{
217    u8 *ihash;
218    unsigned int authsize;
219    struct ablkcipher_request *abreq;
220    struct aead_request *req = areq->data;
221    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
222    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
223    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
224    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
225
226    if (err)
227        goto out;
228
229    authsize = crypto_aead_authsize(authenc);
230    ihash = ahreq->result + authsize;
231    scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
232                 authsize, 0);
233
234    err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG: 0;
235    if (err)
236        goto out;
237
238    abreq = aead_request_ctx(req);
239    ablkcipher_request_set_tfm(abreq, ctx->enc);
240    ablkcipher_request_set_callback(abreq, aead_request_flags(req),
241                    req->base.complete, req->base.data);
242    ablkcipher_request_set_crypt(abreq, req->src, req->dst,
243                     req->cryptlen, req->iv);
244
245    err = crypto_ablkcipher_decrypt(abreq);
246
247out:
248    aead_request_complete(req, err);
249}
250
251static u8 *crypto_authenc_ahash_fb(struct aead_request *req, unsigned int flags)
252{
253    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
254    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
255    struct crypto_ahash *auth = ctx->auth;
256    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
257    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
258    u8 *hash = areq_ctx->tail;
259    int err;
260
261    hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
262                crypto_ahash_alignmask(auth) + 1);
263
264    ahash_request_set_tfm(ahreq, auth);
265
266    err = crypto_ahash_init(ahreq);
267    if (err)
268        return ERR_PTR(err);
269
270    ahash_request_set_crypt(ahreq, req->assoc, hash, req->assoclen);
271    ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
272                   areq_ctx->update_complete, req);
273
274    err = crypto_ahash_update(ahreq);
275    if (err)
276        return ERR_PTR(err);
277
278    ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
279                areq_ctx->cryptlen);
280    ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
281                   areq_ctx->complete, req);
282
283    err = crypto_ahash_finup(ahreq);
284    if (err)
285        return ERR_PTR(err);
286
287    return hash;
288}
289
290static u8 *crypto_authenc_ahash(struct aead_request *req, unsigned int flags)
291{
292    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
293    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
294    struct crypto_ahash *auth = ctx->auth;
295    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
296    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
297    u8 *hash = areq_ctx->tail;
298    int err;
299
300    hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
301               crypto_ahash_alignmask(auth) + 1);
302
303    ahash_request_set_tfm(ahreq, auth);
304    ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
305                areq_ctx->cryptlen);
306    ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
307                   areq_ctx->complete, req);
308
309    err = crypto_ahash_digest(ahreq);
310    if (err)
311        return ERR_PTR(err);
312
313    return hash;
314}
315
316static int crypto_authenc_genicv(struct aead_request *req, u8 *iv,
317                 unsigned int flags)
318{
319    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
320    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
321    struct scatterlist *dst = req->dst;
322    struct scatterlist *assoc = req->assoc;
323    struct scatterlist *cipher = areq_ctx->cipher;
324    struct scatterlist *asg = areq_ctx->asg;
325    unsigned int ivsize = crypto_aead_ivsize(authenc);
326    unsigned int cryptlen = req->cryptlen;
327    authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
328    struct page *dstp;
329    u8 *vdst;
330    u8 *hash;
331
332    dstp = sg_page(dst);
333    vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset;
334
335    if (ivsize) {
336        sg_init_table(cipher, 2);
337        sg_set_buf(cipher, iv, ivsize);
338        authenc_chain(cipher, dst, vdst == iv + ivsize);
339        dst = cipher;
340        cryptlen += ivsize;
341    }
342
343    if (sg_is_last(assoc)) {
344        authenc_ahash_fn = crypto_authenc_ahash;
345        sg_init_table(asg, 2);
346        sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
347        authenc_chain(asg, dst, 0);
348        dst = asg;
349        cryptlen += req->assoclen;
350    }
351
352    areq_ctx->cryptlen = cryptlen;
353    areq_ctx->sg = dst;
354
355    areq_ctx->complete = authenc_geniv_ahash_done;
356    areq_ctx->update_complete = authenc_geniv_ahash_update_done;
357
358    hash = authenc_ahash_fn(req, flags);
359    if (IS_ERR(hash))
360        return PTR_ERR(hash);
361
362    scatterwalk_map_and_copy(hash, dst, cryptlen,
363                 crypto_aead_authsize(authenc), 1);
364    return 0;
365}
366
367static void crypto_authenc_encrypt_done(struct crypto_async_request *req,
368                    int err)
369{
370    struct aead_request *areq = req->data;
371
372    if (!err) {
373        struct crypto_aead *authenc = crypto_aead_reqtfm(areq);
374        struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
375        struct ablkcipher_request *abreq = aead_request_ctx(areq);
376        u8 *iv = (u8 *)(abreq + 1) +
377             crypto_ablkcipher_reqsize(ctx->enc);
378
379        err = crypto_authenc_genicv(areq, iv, 0);
380    }
381
382    aead_request_complete(areq, err);
383}
384
385static int crypto_authenc_encrypt(struct aead_request *req)
386{
387    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
388    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
389    struct ablkcipher_request *abreq = aead_request_ctx(req);
390    struct crypto_ablkcipher *enc = ctx->enc;
391    struct scatterlist *dst = req->dst;
392    unsigned int cryptlen = req->cryptlen;
393    u8 *iv = (u8 *)(abreq + 1) + crypto_ablkcipher_reqsize(enc);
394    int err;
395
396    ablkcipher_request_set_tfm(abreq, enc);
397    ablkcipher_request_set_callback(abreq, aead_request_flags(req),
398                    crypto_authenc_encrypt_done, req);
399    ablkcipher_request_set_crypt(abreq, req->src, dst, cryptlen, req->iv);
400
401    memcpy(iv, req->iv, crypto_aead_ivsize(authenc));
402
403    err = crypto_ablkcipher_encrypt(abreq);
404    if (err)
405        return err;
406
407    return crypto_authenc_genicv(req, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
408}
409
410static void crypto_authenc_givencrypt_done(struct crypto_async_request *req,
411                       int err)
412{
413    struct aead_request *areq = req->data;
414
415    if (!err) {
416        struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
417
418        err = crypto_authenc_genicv(areq, greq->giv, 0);
419    }
420
421    aead_request_complete(areq, err);
422}
423
424static int crypto_authenc_givencrypt(struct aead_givcrypt_request *req)
425{
426    struct crypto_aead *authenc = aead_givcrypt_reqtfm(req);
427    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
428    struct aead_request *areq = &req->areq;
429    struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
430    u8 *iv = req->giv;
431    int err;
432
433    skcipher_givcrypt_set_tfm(greq, ctx->enc);
434    skcipher_givcrypt_set_callback(greq, aead_request_flags(areq),
435                       crypto_authenc_givencrypt_done, areq);
436    skcipher_givcrypt_set_crypt(greq, areq->src, areq->dst, areq->cryptlen,
437                    areq->iv);
438    skcipher_givcrypt_set_giv(greq, iv, req->seq);
439
440    err = crypto_skcipher_givencrypt(greq);
441    if (err)
442        return err;
443
444    return crypto_authenc_genicv(areq, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
445}
446
447static int crypto_authenc_verify(struct aead_request *req,
448                 authenc_ahash_t authenc_ahash_fn)
449{
450    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
451    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
452    u8 *ohash;
453    u8 *ihash;
454    unsigned int authsize;
455
456    areq_ctx->complete = authenc_verify_ahash_done;
457    areq_ctx->complete = authenc_verify_ahash_update_done;
458
459    ohash = authenc_ahash_fn(req, CRYPTO_TFM_REQ_MAY_SLEEP);
460    if (IS_ERR(ohash))
461        return PTR_ERR(ohash);
462
463    authsize = crypto_aead_authsize(authenc);
464    ihash = ohash + authsize;
465    scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
466                 authsize, 0);
467    return memcmp(ihash, ohash, authsize) ? -EBADMSG: 0;
468}
469
470static int crypto_authenc_iverify(struct aead_request *req, u8 *iv,
471                  unsigned int cryptlen)
472{
473    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
474    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
475    struct scatterlist *src = req->src;
476    struct scatterlist *assoc = req->assoc;
477    struct scatterlist *cipher = areq_ctx->cipher;
478    struct scatterlist *asg = areq_ctx->asg;
479    unsigned int ivsize = crypto_aead_ivsize(authenc);
480    authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
481    struct page *srcp;
482    u8 *vsrc;
483
484    srcp = sg_page(src);
485    vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
486
487    if (ivsize) {
488        sg_init_table(cipher, 2);
489        sg_set_buf(cipher, iv, ivsize);
490        authenc_chain(cipher, src, vsrc == iv + ivsize);
491        src = cipher;
492        cryptlen += ivsize;
493    }
494
495    if (sg_is_last(assoc)) {
496        authenc_ahash_fn = crypto_authenc_ahash;
497        sg_init_table(asg, 2);
498        sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
499        authenc_chain(asg, src, 0);
500        src = asg;
501        cryptlen += req->assoclen;
502    }
503
504    areq_ctx->cryptlen = cryptlen;
505    areq_ctx->sg = src;
506
507    return crypto_authenc_verify(req, authenc_ahash_fn);
508}
509
510static int crypto_authenc_decrypt(struct aead_request *req)
511{
512    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
513    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
514    struct ablkcipher_request *abreq = aead_request_ctx(req);
515    unsigned int cryptlen = req->cryptlen;
516    unsigned int authsize = crypto_aead_authsize(authenc);
517    u8 *iv = req->iv;
518    int err;
519
520    if (cryptlen < authsize)
521        return -EINVAL;
522    cryptlen -= authsize;
523
524    err = crypto_authenc_iverify(req, iv, cryptlen);
525    if (err)
526        return err;
527
528    ablkcipher_request_set_tfm(abreq, ctx->enc);
529    ablkcipher_request_set_callback(abreq, aead_request_flags(req),
530                    req->base.complete, req->base.data);
531    ablkcipher_request_set_crypt(abreq, req->src, req->dst, cryptlen, iv);
532
533    return crypto_ablkcipher_decrypt(abreq);
534}
535
536static int crypto_authenc_init_tfm(struct crypto_tfm *tfm)
537{
538    struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
539    struct authenc_instance_ctx *ictx = crypto_instance_ctx(inst);
540    struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
541    struct crypto_ahash *auth;
542    struct crypto_ablkcipher *enc;
543    int err;
544
545    auth = crypto_spawn_ahash(&ictx->auth);
546    if (IS_ERR(auth))
547        return PTR_ERR(auth);
548
549    ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) +
550                crypto_ahash_alignmask(auth),
551                crypto_ahash_alignmask(auth) + 1);
552
553    enc = crypto_spawn_skcipher(&ictx->enc);
554    err = PTR_ERR(enc);
555    if (IS_ERR(enc))
556        goto err_free_ahash;
557
558    ctx->auth = auth;
559    ctx->enc = enc;
560    
561    tfm->crt_aead.reqsize = max_t(unsigned int,
562                crypto_ahash_reqsize(auth) + ctx->reqoff +
563                sizeof(struct authenc_request_ctx) +
564                sizeof(struct ahash_request),
565                sizeof(struct skcipher_givcrypt_request) +
566                crypto_ablkcipher_reqsize(enc) +
567                crypto_ablkcipher_ivsize(enc));
568
569    return 0;
570
571err_free_ahash:
572    crypto_free_ahash(auth);
573    return err;
574}
575
576static void crypto_authenc_exit_tfm(struct crypto_tfm *tfm)
577{
578    struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
579
580    crypto_free_ahash(ctx->auth);
581    crypto_free_ablkcipher(ctx->enc);
582}
583
584static struct crypto_instance *crypto_authenc_alloc(struct rtattr **tb)
585{
586    struct crypto_attr_type *algt;
587    struct crypto_instance *inst;
588    struct hash_alg_common *auth;
589    struct crypto_alg *auth_base;
590    struct crypto_alg *enc;
591    struct authenc_instance_ctx *ctx;
592    const char *enc_name;
593    int err;
594
595    algt = crypto_get_attr_type(tb);
596    err = PTR_ERR(algt);
597    if (IS_ERR(algt))
598        return ERR_PTR(err);
599
600    if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
601        return ERR_PTR(-EINVAL);
602
603    auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
604                   CRYPTO_ALG_TYPE_AHASH_MASK);
605    if (IS_ERR(auth))
606        return ERR_PTR(PTR_ERR(auth));
607
608    auth_base = &auth->base;
609
610    enc_name = crypto_attr_alg_name(tb[2]);
611    err = PTR_ERR(enc_name);
612    if (IS_ERR(enc_name))
613        goto out_put_auth;
614
615    inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
616    err = -ENOMEM;
617    if (!inst)
618        goto out_put_auth;
619
620    ctx = crypto_instance_ctx(inst);
621
622    err = crypto_init_ahash_spawn(&ctx->auth, auth, inst);
623    if (err)
624        goto err_free_inst;
625
626    crypto_set_skcipher_spawn(&ctx->enc, inst);
627    err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
628                   crypto_requires_sync(algt->type,
629                            algt->mask));
630    if (err)
631        goto err_drop_auth;
632
633    enc = crypto_skcipher_spawn_alg(&ctx->enc);
634
635    err = -ENAMETOOLONG;
636    if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
637             "authenc(%s,%s)", auth_base->cra_name, enc->cra_name) >=
638        CRYPTO_MAX_ALG_NAME)
639        goto err_drop_enc;
640
641    if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
642             "authenc(%s,%s)", auth_base->cra_driver_name,
643             enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
644        goto err_drop_enc;
645
646    inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
647    inst->alg.cra_flags |= enc->cra_flags & CRYPTO_ALG_ASYNC;
648    inst->alg.cra_priority = enc->cra_priority *
649                 10 + auth_base->cra_priority;
650    inst->alg.cra_blocksize = enc->cra_blocksize;
651    inst->alg.cra_alignmask = auth_base->cra_alignmask | enc->cra_alignmask;
652    inst->alg.cra_type = &crypto_aead_type;
653
654    inst->alg.cra_aead.ivsize = enc->cra_ablkcipher.ivsize;
655    inst->alg.cra_aead.maxauthsize = auth->digestsize;
656
657    inst->alg.cra_ctxsize = sizeof(struct crypto_authenc_ctx);
658
659    inst->alg.cra_init = crypto_authenc_init_tfm;
660    inst->alg.cra_exit = crypto_authenc_exit_tfm;
661
662    inst->alg.cra_aead.setkey = crypto_authenc_setkey;
663    inst->alg.cra_aead.encrypt = crypto_authenc_encrypt;
664    inst->alg.cra_aead.decrypt = crypto_authenc_decrypt;
665    inst->alg.cra_aead.givencrypt = crypto_authenc_givencrypt;
666
667out:
668    crypto_mod_put(auth_base);
669    return inst;
670
671err_drop_enc:
672    crypto_drop_skcipher(&ctx->enc);
673err_drop_auth:
674    crypto_drop_ahash(&ctx->auth);
675err_free_inst:
676    kfree(inst);
677out_put_auth:
678    inst = ERR_PTR(err);
679    goto out;
680}
681
682static void crypto_authenc_free(struct crypto_instance *inst)
683{
684    struct authenc_instance_ctx *ctx = crypto_instance_ctx(inst);
685
686    crypto_drop_skcipher(&ctx->enc);
687    crypto_drop_ahash(&ctx->auth);
688    kfree(inst);
689}
690
691static struct crypto_template crypto_authenc_tmpl = {
692    .name = "authenc",
693    .alloc = crypto_authenc_alloc,
694    .free = crypto_authenc_free,
695    .module = THIS_MODULE,
696};
697
698static int __init crypto_authenc_module_init(void)
699{
700    return crypto_register_template(&crypto_authenc_tmpl);
701}
702
703static void __exit crypto_authenc_module_exit(void)
704{
705    crypto_unregister_template(&crypto_authenc_tmpl);
706}
707
708module_init(crypto_authenc_module_init);
709module_exit(crypto_authenc_module_exit);
710
711MODULE_LICENSE("GPL");
712MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");
713

Archive Download this file



interactive