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 void authenc_request_complete(struct aead_request *req, int err)
50{
51    if (err != -EINPROGRESS)
52        aead_request_complete(req, err);
53}
54
55int crypto_authenc_extractkeys(struct crypto_authenc_keys *keys, const u8 *key,
56                   unsigned int keylen)
57{
58    struct rtattr *rta = (struct rtattr *)key;
59    struct crypto_authenc_key_param *param;
60
61    if (!RTA_OK(rta, keylen))
62        return -EINVAL;
63    if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM)
64        return -EINVAL;
65    if (RTA_PAYLOAD(rta) < sizeof(*param))
66        return -EINVAL;
67
68    param = RTA_DATA(rta);
69    keys->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 < keys->enckeylen)
75        return -EINVAL;
76
77    keys->authkeylen = keylen - keys->enckeylen;
78    keys->authkey = key;
79    keys->enckey = key + keys->authkeylen;
80
81    return 0;
82}
83EXPORT_SYMBOL_GPL(crypto_authenc_extractkeys);
84
85static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
86                 unsigned int keylen)
87{
88    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
89    struct crypto_ahash *auth = ctx->auth;
90    struct crypto_ablkcipher *enc = ctx->enc;
91    struct crypto_authenc_keys keys;
92    int err = -EINVAL;
93
94    if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
95        goto badkey;
96
97    crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
98    crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) &
99                    CRYPTO_TFM_REQ_MASK);
100    err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
101    crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) &
102                       CRYPTO_TFM_RES_MASK);
103
104    if (err)
105        goto out;
106
107    crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
108    crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
109                     CRYPTO_TFM_REQ_MASK);
110    err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen);
111    crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) &
112                       CRYPTO_TFM_RES_MASK);
113
114out:
115    return err;
116
117badkey:
118    crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN);
119    goto out;
120}
121
122static void authenc_geniv_ahash_update_done(struct crypto_async_request *areq,
123                        int err)
124{
125    struct aead_request *req = areq->data;
126    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
127    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
128    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
129    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
130
131    if (err)
132        goto out;
133
134    ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
135                areq_ctx->cryptlen);
136    ahash_request_set_callback(ahreq, aead_request_flags(req) &
137                      CRYPTO_TFM_REQ_MAY_SLEEP,
138                   areq_ctx->complete, req);
139
140    err = crypto_ahash_finup(ahreq);
141    if (err)
142        goto out;
143
144    scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
145                 areq_ctx->cryptlen,
146                 crypto_aead_authsize(authenc), 1);
147
148out:
149    authenc_request_complete(req, err);
150}
151
152static void authenc_geniv_ahash_done(struct crypto_async_request *areq, int err)
153{
154    struct aead_request *req = areq->data;
155    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
156    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
157    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
158    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
159
160    if (err)
161        goto out;
162
163    scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
164                 areq_ctx->cryptlen,
165                 crypto_aead_authsize(authenc), 1);
166
167out:
168    aead_request_complete(req, err);
169}
170
171static void authenc_verify_ahash_update_done(struct crypto_async_request *areq,
172                         int err)
173{
174    u8 *ihash;
175    unsigned int authsize;
176    struct ablkcipher_request *abreq;
177    struct aead_request *req = areq->data;
178    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
179    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
180    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
181    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
182    unsigned int cryptlen = req->cryptlen;
183
184    if (err)
185        goto out;
186
187    ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
188                areq_ctx->cryptlen);
189    ahash_request_set_callback(ahreq, aead_request_flags(req) &
190                      CRYPTO_TFM_REQ_MAY_SLEEP,
191                   areq_ctx->complete, req);
192
193    err = crypto_ahash_finup(ahreq);
194    if (err)
195        goto out;
196
197    authsize = crypto_aead_authsize(authenc);
198    cryptlen -= authsize;
199    ihash = ahreq->result + authsize;
200    scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
201                 authsize, 0);
202
203    err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
204    if (err)
205        goto out;
206
207    abreq = aead_request_ctx(req);
208    ablkcipher_request_set_tfm(abreq, ctx->enc);
209    ablkcipher_request_set_callback(abreq, aead_request_flags(req),
210                    req->base.complete, req->base.data);
211    ablkcipher_request_set_crypt(abreq, req->src, req->dst,
212                     cryptlen, req->iv);
213
214    err = crypto_ablkcipher_decrypt(abreq);
215
216out:
217    authenc_request_complete(req, err);
218}
219
220static void authenc_verify_ahash_done(struct crypto_async_request *areq,
221                      int err)
222{
223    u8 *ihash;
224    unsigned int authsize;
225    struct ablkcipher_request *abreq;
226    struct aead_request *req = areq->data;
227    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
228    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
229    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
230    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
231    unsigned int cryptlen = req->cryptlen;
232
233    if (err)
234        goto out;
235
236    authsize = crypto_aead_authsize(authenc);
237    cryptlen -= authsize;
238    ihash = ahreq->result + authsize;
239    scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
240                 authsize, 0);
241
242    err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
243    if (err)
244        goto out;
245
246    abreq = aead_request_ctx(req);
247    ablkcipher_request_set_tfm(abreq, ctx->enc);
248    ablkcipher_request_set_callback(abreq, aead_request_flags(req),
249                    req->base.complete, req->base.data);
250    ablkcipher_request_set_crypt(abreq, req->src, req->dst,
251                     cryptlen, req->iv);
252
253    err = crypto_ablkcipher_decrypt(abreq);
254
255out:
256    authenc_request_complete(req, err);
257}
258
259static u8 *crypto_authenc_ahash_fb(struct aead_request *req, unsigned int flags)
260{
261    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
262    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
263    struct crypto_ahash *auth = ctx->auth;
264    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
265    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
266    u8 *hash = areq_ctx->tail;
267    int err;
268
269    hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
270                crypto_ahash_alignmask(auth) + 1);
271
272    ahash_request_set_tfm(ahreq, auth);
273
274    err = crypto_ahash_init(ahreq);
275    if (err)
276        return ERR_PTR(err);
277
278    ahash_request_set_crypt(ahreq, req->assoc, hash, req->assoclen);
279    ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
280                   areq_ctx->update_complete, req);
281
282    err = crypto_ahash_update(ahreq);
283    if (err)
284        return ERR_PTR(err);
285
286    ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
287                areq_ctx->cryptlen);
288    ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
289                   areq_ctx->complete, req);
290
291    err = crypto_ahash_finup(ahreq);
292    if (err)
293        return ERR_PTR(err);
294
295    return hash;
296}
297
298static u8 *crypto_authenc_ahash(struct aead_request *req, unsigned int flags)
299{
300    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
301    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
302    struct crypto_ahash *auth = ctx->auth;
303    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
304    struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
305    u8 *hash = areq_ctx->tail;
306    int err;
307
308    hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
309               crypto_ahash_alignmask(auth) + 1);
310
311    ahash_request_set_tfm(ahreq, auth);
312    ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
313                areq_ctx->cryptlen);
314    ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
315                   areq_ctx->complete, req);
316
317    err = crypto_ahash_digest(ahreq);
318    if (err)
319        return ERR_PTR(err);
320
321    return hash;
322}
323
324static int crypto_authenc_genicv(struct aead_request *req, u8 *iv,
325                 unsigned int flags)
326{
327    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
328    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
329    struct scatterlist *dst = req->dst;
330    struct scatterlist *assoc = req->assoc;
331    struct scatterlist *cipher = areq_ctx->cipher;
332    struct scatterlist *asg = areq_ctx->asg;
333    unsigned int ivsize = crypto_aead_ivsize(authenc);
334    unsigned int cryptlen = req->cryptlen;
335    authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
336    struct page *dstp;
337    u8 *vdst;
338    u8 *hash;
339
340    dstp = sg_page(dst);
341    vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset;
342
343    if (ivsize) {
344        sg_init_table(cipher, 2);
345        sg_set_buf(cipher, iv, ivsize);
346        scatterwalk_crypto_chain(cipher, dst, vdst == iv + ivsize, 2);
347        dst = cipher;
348        cryptlen += ivsize;
349    }
350
351    if (req->assoclen && sg_is_last(assoc)) {
352        authenc_ahash_fn = crypto_authenc_ahash;
353        sg_init_table(asg, 2);
354        sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
355        scatterwalk_crypto_chain(asg, dst, 0, 2);
356        dst = asg;
357        cryptlen += req->assoclen;
358    }
359
360    areq_ctx->cryptlen = cryptlen;
361    areq_ctx->sg = dst;
362
363    areq_ctx->complete = authenc_geniv_ahash_done;
364    areq_ctx->update_complete = authenc_geniv_ahash_update_done;
365
366    hash = authenc_ahash_fn(req, flags);
367    if (IS_ERR(hash))
368        return PTR_ERR(hash);
369
370    scatterwalk_map_and_copy(hash, dst, cryptlen,
371                 crypto_aead_authsize(authenc), 1);
372    return 0;
373}
374
375static void crypto_authenc_encrypt_done(struct crypto_async_request *req,
376                    int err)
377{
378    struct aead_request *areq = req->data;
379
380    if (!err) {
381        struct crypto_aead *authenc = crypto_aead_reqtfm(areq);
382        struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
383        struct authenc_request_ctx *areq_ctx = aead_request_ctx(areq);
384        struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
385                                + ctx->reqoff);
386        u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(ctx->enc);
387
388        err = crypto_authenc_genicv(areq, iv, 0);
389    }
390
391    authenc_request_complete(areq, err);
392}
393
394static int crypto_authenc_encrypt(struct aead_request *req)
395{
396    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
397    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
398    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
399    struct crypto_ablkcipher *enc = ctx->enc;
400    struct scatterlist *dst = req->dst;
401    unsigned int cryptlen = req->cryptlen;
402    struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
403                            + ctx->reqoff);
404    u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(enc);
405    int err;
406
407    ablkcipher_request_set_tfm(abreq, enc);
408    ablkcipher_request_set_callback(abreq, aead_request_flags(req),
409                    crypto_authenc_encrypt_done, req);
410    ablkcipher_request_set_crypt(abreq, req->src, dst, cryptlen, req->iv);
411
412    memcpy(iv, req->iv, crypto_aead_ivsize(authenc));
413
414    err = crypto_ablkcipher_encrypt(abreq);
415    if (err)
416        return err;
417
418    return crypto_authenc_genicv(req, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
419}
420
421static void crypto_authenc_givencrypt_done(struct crypto_async_request *req,
422                       int err)
423{
424    struct aead_request *areq = req->data;
425
426    if (!err) {
427        struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
428
429        err = crypto_authenc_genicv(areq, greq->giv, 0);
430    }
431
432    authenc_request_complete(areq, err);
433}
434
435static int crypto_authenc_givencrypt(struct aead_givcrypt_request *req)
436{
437    struct crypto_aead *authenc = aead_givcrypt_reqtfm(req);
438    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
439    struct aead_request *areq = &req->areq;
440    struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
441    u8 *iv = req->giv;
442    int err;
443
444    skcipher_givcrypt_set_tfm(greq, ctx->enc);
445    skcipher_givcrypt_set_callback(greq, aead_request_flags(areq),
446                       crypto_authenc_givencrypt_done, areq);
447    skcipher_givcrypt_set_crypt(greq, areq->src, areq->dst, areq->cryptlen,
448                    areq->iv);
449    skcipher_givcrypt_set_giv(greq, iv, req->seq);
450
451    err = crypto_skcipher_givencrypt(greq);
452    if (err)
453        return err;
454
455    return crypto_authenc_genicv(areq, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
456}
457
458static int crypto_authenc_verify(struct aead_request *req,
459                 authenc_ahash_t authenc_ahash_fn)
460{
461    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
462    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
463    u8 *ohash;
464    u8 *ihash;
465    unsigned int authsize;
466
467    areq_ctx->complete = authenc_verify_ahash_done;
468    areq_ctx->update_complete = authenc_verify_ahash_update_done;
469
470    ohash = authenc_ahash_fn(req, CRYPTO_TFM_REQ_MAY_SLEEP);
471    if (IS_ERR(ohash))
472        return PTR_ERR(ohash);
473
474    authsize = crypto_aead_authsize(authenc);
475    ihash = ohash + authsize;
476    scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
477                 authsize, 0);
478    return crypto_memneq(ihash, ohash, authsize) ? -EBADMSG : 0;
479}
480
481static int crypto_authenc_iverify(struct aead_request *req, u8 *iv,
482                  unsigned int cryptlen)
483{
484    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
485    struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
486    struct scatterlist *src = req->src;
487    struct scatterlist *assoc = req->assoc;
488    struct scatterlist *cipher = areq_ctx->cipher;
489    struct scatterlist *asg = areq_ctx->asg;
490    unsigned int ivsize = crypto_aead_ivsize(authenc);
491    authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
492    struct page *srcp;
493    u8 *vsrc;
494
495    srcp = sg_page(src);
496    vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
497
498    if (ivsize) {
499        sg_init_table(cipher, 2);
500        sg_set_buf(cipher, iv, ivsize);
501        scatterwalk_crypto_chain(cipher, src, vsrc == iv + ivsize, 2);
502        src = cipher;
503        cryptlen += ivsize;
504    }
505
506    if (req->assoclen && sg_is_last(assoc)) {
507        authenc_ahash_fn = crypto_authenc_ahash;
508        sg_init_table(asg, 2);
509        sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
510        scatterwalk_crypto_chain(asg, src, 0, 2);
511        src = asg;
512        cryptlen += req->assoclen;
513    }
514
515    areq_ctx->cryptlen = cryptlen;
516    areq_ctx->sg = src;
517
518    return crypto_authenc_verify(req, authenc_ahash_fn);
519}
520
521static int crypto_authenc_decrypt(struct aead_request *req)
522{
523    struct crypto_aead *authenc = crypto_aead_reqtfm(req);
524    struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
525    struct ablkcipher_request *abreq = aead_request_ctx(req);
526    unsigned int cryptlen = req->cryptlen;
527    unsigned int authsize = crypto_aead_authsize(authenc);
528    u8 *iv = req->iv;
529    int err;
530
531    if (cryptlen < authsize)
532        return -EINVAL;
533    cryptlen -= authsize;
534
535    err = crypto_authenc_iverify(req, iv, cryptlen);
536    if (err)
537        return err;
538
539    ablkcipher_request_set_tfm(abreq, ctx->enc);
540    ablkcipher_request_set_callback(abreq, aead_request_flags(req),
541                    req->base.complete, req->base.data);
542    ablkcipher_request_set_crypt(abreq, req->src, req->dst, cryptlen, iv);
543
544    return crypto_ablkcipher_decrypt(abreq);
545}
546
547static int crypto_authenc_init_tfm(struct crypto_tfm *tfm)
548{
549    struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
550    struct authenc_instance_ctx *ictx = crypto_instance_ctx(inst);
551    struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
552    struct crypto_ahash *auth;
553    struct crypto_ablkcipher *enc;
554    int err;
555
556    auth = crypto_spawn_ahash(&ictx->auth);
557    if (IS_ERR(auth))
558        return PTR_ERR(auth);
559
560    enc = crypto_spawn_skcipher(&ictx->enc);
561    err = PTR_ERR(enc);
562    if (IS_ERR(enc))
563        goto err_free_ahash;
564
565    ctx->auth = auth;
566    ctx->enc = enc;
567
568    ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) +
569                crypto_ahash_alignmask(auth),
570                crypto_ahash_alignmask(auth) + 1) +
571              crypto_ablkcipher_ivsize(enc);
572
573    tfm->crt_aead.reqsize = sizeof(struct authenc_request_ctx) +
574                ctx->reqoff +
575                max_t(unsigned int,
576                crypto_ahash_reqsize(auth) +
577                sizeof(struct ahash_request),
578                sizeof(struct skcipher_givcrypt_request) +
579                crypto_ablkcipher_reqsize(enc));
580
581    return 0;
582
583err_free_ahash:
584    crypto_free_ahash(auth);
585    return err;
586}
587
588static void crypto_authenc_exit_tfm(struct crypto_tfm *tfm)
589{
590    struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
591
592    crypto_free_ahash(ctx->auth);
593    crypto_free_ablkcipher(ctx->enc);
594}
595
596static struct crypto_instance *crypto_authenc_alloc(struct rtattr **tb)
597{
598    struct crypto_attr_type *algt;
599    struct crypto_instance *inst;
600    struct hash_alg_common *auth;
601    struct crypto_alg *auth_base;
602    struct crypto_alg *enc;
603    struct authenc_instance_ctx *ctx;
604    const char *enc_name;
605    int err;
606
607    algt = crypto_get_attr_type(tb);
608    if (IS_ERR(algt))
609        return ERR_CAST(algt);
610
611    if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
612        return ERR_PTR(-EINVAL);
613
614    auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
615                   CRYPTO_ALG_TYPE_AHASH_MASK);
616    if (IS_ERR(auth))
617        return ERR_CAST(auth);
618
619    auth_base = &auth->base;
620
621    enc_name = crypto_attr_alg_name(tb[2]);
622    err = PTR_ERR(enc_name);
623    if (IS_ERR(enc_name))
624        goto out_put_auth;
625
626    inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
627    err = -ENOMEM;
628    if (!inst)
629        goto out_put_auth;
630
631    ctx = crypto_instance_ctx(inst);
632
633    err = crypto_init_ahash_spawn(&ctx->auth, auth, inst);
634    if (err)
635        goto err_free_inst;
636
637    crypto_set_skcipher_spawn(&ctx->enc, inst);
638    err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
639                   crypto_requires_sync(algt->type,
640                            algt->mask));
641    if (err)
642        goto err_drop_auth;
643
644    enc = crypto_skcipher_spawn_alg(&ctx->enc);
645
646    err = -ENAMETOOLONG;
647    if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
648             "authenc(%s,%s)", auth_base->cra_name, enc->cra_name) >=
649        CRYPTO_MAX_ALG_NAME)
650        goto err_drop_enc;
651
652    if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
653             "authenc(%s,%s)", auth_base->cra_driver_name,
654             enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
655        goto err_drop_enc;
656
657    inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
658    inst->alg.cra_flags |= enc->cra_flags & CRYPTO_ALG_ASYNC;
659    inst->alg.cra_priority = enc->cra_priority *
660                 10 + auth_base->cra_priority;
661    inst->alg.cra_blocksize = enc->cra_blocksize;
662    inst->alg.cra_alignmask = auth_base->cra_alignmask | enc->cra_alignmask;
663    inst->alg.cra_type = &crypto_aead_type;
664
665    inst->alg.cra_aead.ivsize = enc->cra_ablkcipher.ivsize;
666    inst->alg.cra_aead.maxauthsize = auth->digestsize;
667
668    inst->alg.cra_ctxsize = sizeof(struct crypto_authenc_ctx);
669
670    inst->alg.cra_init = crypto_authenc_init_tfm;
671    inst->alg.cra_exit = crypto_authenc_exit_tfm;
672
673    inst->alg.cra_aead.setkey = crypto_authenc_setkey;
674    inst->alg.cra_aead.encrypt = crypto_authenc_encrypt;
675    inst->alg.cra_aead.decrypt = crypto_authenc_decrypt;
676    inst->alg.cra_aead.givencrypt = crypto_authenc_givencrypt;
677
678out:
679    crypto_mod_put(auth_base);
680    return inst;
681
682err_drop_enc:
683    crypto_drop_skcipher(&ctx->enc);
684err_drop_auth:
685    crypto_drop_ahash(&ctx->auth);
686err_free_inst:
687    kfree(inst);
688out_put_auth:
689    inst = ERR_PTR(err);
690    goto out;
691}
692
693static void crypto_authenc_free(struct crypto_instance *inst)
694{
695    struct authenc_instance_ctx *ctx = crypto_instance_ctx(inst);
696
697    crypto_drop_skcipher(&ctx->enc);
698    crypto_drop_ahash(&ctx->auth);
699    kfree(inst);
700}
701
702static struct crypto_template crypto_authenc_tmpl = {
703    .name = "authenc",
704    .alloc = crypto_authenc_alloc,
705    .free = crypto_authenc_free,
706    .module = THIS_MODULE,
707};
708
709static int __init crypto_authenc_module_init(void)
710{
711    return crypto_register_template(&crypto_authenc_tmpl);
712}
713
714static void __exit crypto_authenc_module_exit(void)
715{
716    crypto_unregister_template(&crypto_authenc_tmpl);
717}
718
719module_init(crypto_authenc_module_init);
720module_exit(crypto_authenc_module_exit);
721
722MODULE_LICENSE("GPL");
723MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");
724

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