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
  26 typedef u8 *(*authenc_ahash_t)(struct aead_request *req, unsigned int flags);
  27
  28 struct authenc_instance_ctx {
  29         struct crypto_ahash_spawn auth;
  30         struct crypto_skcipher_spawn enc;
  31 };
  32
  33 struct crypto_authenc_ctx {
  34         unsigned int reqoff;
  35         struct crypto_ahash *auth;
  36         struct crypto_ablkcipher *enc;
  37 };
  38
  39 struct 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
  49 static void authenc_request_complete(struct aead_request *req, int err)
  50 {
  51         if (err != -EINPROGRESS)
  52                 aead_request_complete(req, err);
  53 }
  54
  55 static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
  56                                  unsigned int keylen)
  57 {
  58         unsigned int authkeylen;
  59         unsigned int enckeylen;
  60         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
  61         struct crypto_ahash *auth = ctx->auth;
  62         struct crypto_ablkcipher *enc = ctx->enc;
  63         struct rtattr *rta = (void *)key;
  64         struct crypto_authenc_key_param *param;
  65         int err = -EINVAL;
  66
  67         if (!RTA_OK(rta, keylen))
  68                 goto badkey;
  69         if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM)
  70                 goto badkey;
  71         if (RTA_PAYLOAD(rta) < sizeof(*param))
  72                 goto badkey;
  73
  74         param = RTA_DATA(rta);
  75         enckeylen = be32_to_cpu(param->enckeylen);
  76
  77         key += RTA_ALIGN(rta->rta_len);
  78         keylen -= RTA_ALIGN(rta->rta_len);
  79
  80         if (keylen < enckeylen)
  81                 goto badkey;
  82
  83         authkeylen = keylen - enckeylen;
  84
  85         crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
  86         crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) &
  87                                     CRYPTO_TFM_REQ_MASK);
  88         err = crypto_ahash_setkey(auth, key, authkeylen);
  89         crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) &
  90                                        CRYPTO_TFM_RES_MASK);
  91
  92         if (err)
  93                 goto out;
  94
  95         crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
  96         crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
  97                                          CRYPTO_TFM_REQ_MASK);
  98         err = crypto_ablkcipher_setkey(enc, key + authkeylen, enckeylen);
  99         crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) &
 100                                        CRYPTO_TFM_RES_MASK);
 101
 102 out:
 103         return err;
 104
 105 badkey:
 106         crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN);
 107         goto out;
 108 }
 109
 110 static void authenc_chain(struct scatterlist *head, struct scatterlist *sg,
 111                           int chain)
 112 {
 113         if (chain) {
 114                 head->length += sg->length;
 115                 sg = scatterwalk_sg_next(sg);
 116         }
 117
 118         if (sg)
 119                 scatterwalk_sg_chain(head, 2, sg);
 120         else
 121                 sg_mark_end(head);
 122 }
 123
 124 static void authenc_geniv_ahash_update_done(struct crypto_async_request *areq,
 125                                             int err)
 126 {
 127         struct aead_request *req = areq->data;
 128         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 129         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 130         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 131         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 132
 133         if (err)
 134                 goto out;
 135
 136         ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
 137                                 areq_ctx->cryptlen);
 138         ahash_request_set_callback(ahreq, aead_request_flags(req) &
 139                                           CRYPTO_TFM_REQ_MAY_SLEEP,
 140                                    areq_ctx->complete, req);
 141
 142         err = crypto_ahash_finup(ahreq);
 143         if (err)
 144                 goto out;
 145
 146         scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
 147                                  areq_ctx->cryptlen,
 148                                  crypto_aead_authsize(authenc), 1);
 149
 150 out:
 151         authenc_request_complete(req, err);
 152 }
 153
 154 static void authenc_geniv_ahash_done(struct crypto_async_request *areq, int err)
 155 {
 156         struct aead_request *req = areq->data;
 157         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 158         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 159         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 160         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 161
 162         if (err)
 163                 goto out;
 164
 165         scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
 166                                  areq_ctx->cryptlen,
 167                                  crypto_aead_authsize(authenc), 1);
 168
 169 out:
 170         aead_request_complete(req, err);
 171 }
 172
 173 static void authenc_verify_ahash_update_done(struct crypto_async_request *areq,
 174                                              int err)
 175 {
 176         u8 *ihash;
 177         unsigned int authsize;
 178         struct ablkcipher_request *abreq;
 179         struct aead_request *req = areq->data;
 180         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 181         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 182         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 183         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 184         unsigned int cryptlen = req->cryptlen;
 185
 186         if (err)
 187                 goto out;
 188
 189         ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
 190                                 areq_ctx->cryptlen);
 191         ahash_request_set_callback(ahreq, aead_request_flags(req) &
 192                                           CRYPTO_TFM_REQ_MAY_SLEEP,
 193                                    areq_ctx->complete, req);
 194
 195         err = crypto_ahash_finup(ahreq);
 196         if (err)
 197                 goto out;
 198
 199         authsize = crypto_aead_authsize(authenc);
 200         cryptlen -= authsize;
 201         ihash = ahreq->result + authsize;
 202         scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
 203                                  authsize, 0);
 204
 205         err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
 206         if (err)
 207                 goto out;
 208
 209         abreq = aead_request_ctx(req);
 210         ablkcipher_request_set_tfm(abreq, ctx->enc);
 211         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 212                                         req->base.complete, req->base.data);
 213         ablkcipher_request_set_crypt(abreq, req->src, req->dst,
 214                                      cryptlen, req->iv);
 215
 216         err = crypto_ablkcipher_decrypt(abreq);
 217
 218 out:
 219         authenc_request_complete(req, err);
 220 }
 221
 222 static void authenc_verify_ahash_done(struct crypto_async_request *areq,
 223                                       int err)
 224 {
 225         u8 *ihash;
 226         unsigned int authsize;
 227         struct ablkcipher_request *abreq;
 228         struct aead_request *req = areq->data;
 229         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 230         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 231         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 232         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 233         unsigned int cryptlen = req->cryptlen;
 234
 235         if (err)
 236                 goto out;
 237
 238         authsize = crypto_aead_authsize(authenc);
 239         cryptlen -= authsize;
 240         ihash = ahreq->result + authsize;
 241         scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
 242                                  authsize, 0);
 243
 244         err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
 245         if (err)
 246                 goto out;
 247
 248         abreq = aead_request_ctx(req);
 249         ablkcipher_request_set_tfm(abreq, ctx->enc);
 250         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 251                                         req->base.complete, req->base.data);
 252         ablkcipher_request_set_crypt(abreq, req->src, req->dst,
 253                                      cryptlen, req->iv);
 254
 255         err = crypto_ablkcipher_decrypt(abreq);
 256
 257 out:
 258         authenc_request_complete(req, err);
 259 }
 260
 261 static u8 *crypto_authenc_ahash_fb(struct aead_request *req, unsigned int flags)
 262 {
 263         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 264         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 265         struct crypto_ahash *auth = ctx->auth;
 266         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 267         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 268         u8 *hash = areq_ctx->tail;
 269         int err;
 270
 271         hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
 272                             crypto_ahash_alignmask(auth) + 1);
 273
 274         ahash_request_set_tfm(ahreq, auth);
 275
 276         err = crypto_ahash_init(ahreq);
 277         if (err)
 278                 return ERR_PTR(err);
 279
 280         ahash_request_set_crypt(ahreq, req->assoc, hash, req->assoclen);
 281         ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
 282                                    areq_ctx->update_complete, req);
 283
 284         err = crypto_ahash_update(ahreq);
 285         if (err)
 286                 return ERR_PTR(err);
 287
 288         ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
 289                                 areq_ctx->cryptlen);
 290         ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
 291                                    areq_ctx->complete, req);
 292
 293         err = crypto_ahash_finup(ahreq);
 294         if (err)
 295                 return ERR_PTR(err);
 296
 297         return hash;
 298 }
 299
 300 static u8 *crypto_authenc_ahash(struct aead_request *req, unsigned int flags)
 301 {
 302         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 303         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 304         struct crypto_ahash *auth = ctx->auth;
 305         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 306         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 307         u8 *hash = areq_ctx->tail;
 308         int err;
 309
 310         hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
 311                            crypto_ahash_alignmask(auth) + 1);
 312
 313         ahash_request_set_tfm(ahreq, auth);
 314         ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
 315                                 areq_ctx->cryptlen);
 316         ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
 317                                    areq_ctx->complete, req);
 318
 319         err = crypto_ahash_digest(ahreq);
 320         if (err)
 321                 return ERR_PTR(err);
 322
 323         return hash;
 324 }
 325
 326 static int crypto_authenc_genicv(struct aead_request *req, u8 *iv,
 327                                  unsigned int flags)
 328 {
 329         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 330         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 331         struct scatterlist *dst = req->dst;
 332         struct scatterlist *assoc = req->assoc;
 333         struct scatterlist *cipher = areq_ctx->cipher;
 334         struct scatterlist *asg = areq_ctx->asg;
 335         unsigned int ivsize = crypto_aead_ivsize(authenc);
 336         unsigned int cryptlen = req->cryptlen;
 337         authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
 338         struct page *dstp;
 339         u8 *vdst;
 340         u8 *hash;
 341
 342         dstp = sg_page(dst);
 343         vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset;
 344
 345         if (ivsize) {
 346                 sg_init_table(cipher, 2);
 347                 sg_set_buf(cipher, iv, ivsize);
 348                 authenc_chain(cipher, dst, vdst == iv + ivsize);
 349                 dst = cipher;
 350                 cryptlen += ivsize;
 351         }
 352
 353         if (sg_is_last(assoc)) {
 354                 authenc_ahash_fn = crypto_authenc_ahash;
 355                 sg_init_table(asg, 2);
 356                 sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
 357                 authenc_chain(asg, dst, 0);
 358                 dst = asg;
 359                 cryptlen += req->assoclen;
 360         }
 361
 362         areq_ctx->cryptlen = cryptlen;
 363         areq_ctx->sg = dst;
 364
 365         areq_ctx->complete = authenc_geniv_ahash_done;
 366         areq_ctx->update_complete = authenc_geniv_ahash_update_done;
 367
 368         hash = authenc_ahash_fn(req, flags);
 369         if (IS_ERR(hash))
 370                 return PTR_ERR(hash);
 371
 372         scatterwalk_map_and_copy(hash, dst, cryptlen,
 373                                  crypto_aead_authsize(authenc), 1);
 374         return 0;
 375 }
 376
 377 static void crypto_authenc_encrypt_done(struct crypto_async_request *req,
 378                                         int err)
 379 {
 380         struct aead_request *areq = req->data;
 381
 382         if (!err) {
 383                 struct crypto_aead *authenc = crypto_aead_reqtfm(areq);
 384                 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 385                 struct ablkcipher_request *abreq = aead_request_ctx(areq);
 386                 u8 *iv = (u8 *)(abreq + 1) +
 387                          crypto_ablkcipher_reqsize(ctx->enc);
 388
 389                 err = crypto_authenc_genicv(areq, iv, 0);
 390         }
 391
 392         authenc_request_complete(areq, err);
 393 }
 394
 395 static int crypto_authenc_encrypt(struct aead_request *req)
 396 {
 397         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 398         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 399         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 400         struct crypto_ablkcipher *enc = ctx->enc;
 401         struct scatterlist *dst = req->dst;
 402         unsigned int cryptlen = req->cryptlen;
 403         struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
 404                                                     + ctx->reqoff);
 405         u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(enc);
 406         int err;
 407
 408         ablkcipher_request_set_tfm(abreq, enc);
 409         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 410                                         crypto_authenc_encrypt_done, req);
 411         ablkcipher_request_set_crypt(abreq, req->src, dst, cryptlen, req->iv);
 412
 413         memcpy(iv, req->iv, crypto_aead_ivsize(authenc));
 414
 415         err = crypto_ablkcipher_encrypt(abreq);
 416         if (err)
 417                 return err;
 418
 419         return crypto_authenc_genicv(req, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
 420 }
 421
 422 static void crypto_authenc_givencrypt_done(struct crypto_async_request *req,
 423                                            int err)
 424 {
 425         struct aead_request *areq = req->data;
 426
 427         if (!err) {
 428                 struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
 429
 430                 err = crypto_authenc_genicv(areq, greq->giv, 0);
 431         }
 432
 433         authenc_request_complete(areq, err);
 434 }
 435
 436 static int crypto_authenc_givencrypt(struct aead_givcrypt_request *req)
 437 {
 438         struct crypto_aead *authenc = aead_givcrypt_reqtfm(req);
 439         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 440         struct aead_request *areq = &req->areq;
 441         struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
 442         u8 *iv = req->giv;
 443         int err;
 444
 445         skcipher_givcrypt_set_tfm(greq, ctx->enc);
 446         skcipher_givcrypt_set_callback(greq, aead_request_flags(areq),
 447                                        crypto_authenc_givencrypt_done, areq);
 448         skcipher_givcrypt_set_crypt(greq, areq->src, areq->dst, areq->cryptlen,
 449                                     areq->iv);
 450         skcipher_givcrypt_set_giv(greq, iv, req->seq);
 451
 452         err = crypto_skcipher_givencrypt(greq);
 453         if (err)
 454                 return err;
 455
 456         return crypto_authenc_genicv(areq, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
 457 }
 458
 459 static int crypto_authenc_verify(struct aead_request *req,
 460                                  authenc_ahash_t authenc_ahash_fn)
 461 {
 462         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 463         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 464         u8 *ohash;
 465         u8 *ihash;
 466         unsigned int authsize;
 467
 468         areq_ctx->complete = authenc_verify_ahash_done;
 469         areq_ctx->update_complete = authenc_verify_ahash_update_done;
 470
 471         ohash = authenc_ahash_fn(req, CRYPTO_TFM_REQ_MAY_SLEEP);
 472         if (IS_ERR(ohash))
 473                 return PTR_ERR(ohash);
 474
 475         authsize = crypto_aead_authsize(authenc);
 476         ihash = ohash + authsize;
 477         scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
 478                                  authsize, 0);
 479         return memcmp(ihash, ohash, authsize) ? -EBADMSG : 0;
 480 }
 481
 482 static int crypto_authenc_iverify(struct aead_request *req, u8 *iv,
 483                                   unsigned int cryptlen)
 484 {
 485         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 486         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 487         struct scatterlist *src = req->src;
 488         struct scatterlist *assoc = req->assoc;
 489         struct scatterlist *cipher = areq_ctx->cipher;
 490         struct scatterlist *asg = areq_ctx->asg;
 491         unsigned int ivsize = crypto_aead_ivsize(authenc);
 492         authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
 493         struct page *srcp;
 494         u8 *vsrc;
 495
 496         srcp = sg_page(src);
 497         vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
 498
 499         if (ivsize) {
 500                 sg_init_table(cipher, 2);
 501                 sg_set_buf(cipher, iv, ivsize);
 502                 authenc_chain(cipher, src, vsrc == iv + ivsize);
 503                 src = cipher;
 504                 cryptlen += ivsize;
 505         }
 506
 507         if (sg_is_last(assoc)) {
 508                 authenc_ahash_fn = crypto_authenc_ahash;
 509                 sg_init_table(asg, 2);
 510                 sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
 511                 authenc_chain(asg, src, 0);
 512                 src = asg;
 513                 cryptlen += req->assoclen;
 514         }
 515
 516         areq_ctx->cryptlen = cryptlen;
 517         areq_ctx->sg = src;
 518
 519         return crypto_authenc_verify(req, authenc_ahash_fn);
 520 }
 521
 522 static int crypto_authenc_decrypt(struct aead_request *req)
 523 {
 524         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 525         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 526         struct ablkcipher_request *abreq = aead_request_ctx(req);
 527         unsigned int cryptlen = req->cryptlen;
 528         unsigned int authsize = crypto_aead_authsize(authenc);
 529         u8 *iv = req->iv;
 530         int err;
 531
 532         if (cryptlen < authsize)
 533                 return -EINVAL;
 534         cryptlen -= authsize;
 535
 536         err = crypto_authenc_iverify(req, iv, cryptlen);
 537         if (err)
 538                 return err;
 539
 540         ablkcipher_request_set_tfm(abreq, ctx->enc);
 541         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 542                                         req->base.complete, req->base.data);
 543         ablkcipher_request_set_crypt(abreq, req->src, req->dst, cryptlen, iv);
 544
 545         return crypto_ablkcipher_decrypt(abreq);
 546 }
 547
 548 static int crypto_authenc_init_tfm(struct crypto_tfm *tfm)
 549 {
 550         struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
 551         struct authenc_instance_ctx *ictx = crypto_instance_ctx(inst);
 552         struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
 553         struct crypto_ahash *auth;
 554         struct crypto_ablkcipher *enc;
 555         int err;
 556
 557         auth = crypto_spawn_ahash(&ictx->auth);
 558         if (IS_ERR(auth))
 559                 return PTR_ERR(auth);
 560
 561         enc = crypto_spawn_skcipher(&ictx->enc);
 562         err = PTR_ERR(enc);
 563         if (IS_ERR(enc))
 564                 goto err_free_ahash;
 565
 566         ctx->auth = auth;
 567         ctx->enc = enc;
 568
 569         ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) +
 570                             crypto_ahash_alignmask(auth),
 571                             crypto_ahash_alignmask(auth) + 1) +
 572                       crypto_ablkcipher_ivsize(enc);
 573
 574         tfm->crt_aead.reqsize = sizeof(struct authenc_request_ctx) +
 575                                 ctx->reqoff +
 576                                 max_t(unsigned int,
 577                                 crypto_ahash_reqsize(auth) +
 578                                 sizeof(struct ahash_request),
 579                                 sizeof(struct skcipher_givcrypt_request) +
 580                                 crypto_ablkcipher_reqsize(enc));
 581
 582         return 0;
 583
 584 err_free_ahash:
 585         crypto_free_ahash(auth);
 586         return err;
 587 }
 588
 589 static void crypto_authenc_exit_tfm(struct crypto_tfm *tfm)
 590 {
 591         struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
 592
 593         crypto_free_ahash(ctx->auth);
 594         crypto_free_ablkcipher(ctx->enc);
 595 }
 596
 597 static struct crypto_instance *crypto_authenc_alloc(struct rtattr **tb)
 598 {
 599         struct crypto_attr_type *algt;
 600         struct crypto_instance *inst;
 601         struct hash_alg_common *auth;
 602         struct crypto_alg *auth_base;
 603         struct crypto_alg *enc;
 604         struct authenc_instance_ctx *ctx;
 605         const char *enc_name;
 606         int err;
 607
 608         algt = crypto_get_attr_type(tb);
 609         err = PTR_ERR(algt);
 610         if (IS_ERR(algt))
 611                 return ERR_PTR(err);
 612
 613         if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
 614                 return ERR_PTR(-EINVAL);
 615
 616         auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
 617                                CRYPTO_ALG_TYPE_AHASH_MASK);
 618         if (IS_ERR(auth))
 619                 return ERR_CAST(auth);
 620
 621         auth_base = &auth->base;
 622
 623         enc_name = crypto_attr_alg_name(tb[2]);
 624         err = PTR_ERR(enc_name);
 625         if (IS_ERR(enc_name))
 626                 goto out_put_auth;
 627
 628         inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
 629         err = -ENOMEM;
 630         if (!inst)
 631                 goto out_put_auth;
 632
 633         ctx = crypto_instance_ctx(inst);
 634
 635         err = crypto_init_ahash_spawn(&ctx->auth, auth, inst);
 636         if (err)
 637                 goto err_free_inst;
 638
 639         crypto_set_skcipher_spawn(&ctx->enc, inst);
 640         err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
 641                                    crypto_requires_sync(algt->type,
 642                                                         algt->mask));
 643         if (err)
 644                 goto err_drop_auth;
 645
 646         enc = crypto_skcipher_spawn_alg(&ctx->enc);
 647
 648         err = -ENAMETOOLONG;
 649         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
 650                      "authenc(%s,%s)", auth_base->cra_name, enc->cra_name) >=
 651             CRYPTO_MAX_ALG_NAME)
 652                 goto err_drop_enc;
 653
 654         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
 655                      "authenc(%s,%s)", auth_base->cra_driver_name,
 656                      enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 657                 goto err_drop_enc;
 658
 659         inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
 660         inst->alg.cra_flags |= enc->cra_flags & CRYPTO_ALG_ASYNC;
 661         inst->alg.cra_priority = enc->cra_priority *
 662                                  10 + auth_base->cra_priority;
 663         inst->alg.cra_blocksize = enc->cra_blocksize;
 664         inst->alg.cra_alignmask = auth_base->cra_alignmask | enc->cra_alignmask;
 665         inst->alg.cra_type = &crypto_aead_type;
 666
 667         inst->alg.cra_aead.ivsize = enc->cra_ablkcipher.ivsize;
 668         inst->alg.cra_aead.maxauthsize = auth->digestsize;
 669
 670         inst->alg.cra_ctxsize = sizeof(struct crypto_authenc_ctx);
 671
 672         inst->alg.cra_init = crypto_authenc_init_tfm;
 673         inst->alg.cra_exit = crypto_authenc_exit_tfm;
 674
 675         inst->alg.cra_aead.setkey = crypto_authenc_setkey;
 676         inst->alg.cra_aead.encrypt = crypto_authenc_encrypt;
 677         inst->alg.cra_aead.decrypt = crypto_authenc_decrypt;
 678         inst->alg.cra_aead.givencrypt = crypto_authenc_givencrypt;
 679
 680 out:
 681         crypto_mod_put(auth_base);
 682         return inst;
 683
 684 err_drop_enc:
 685         crypto_drop_skcipher(&ctx->enc);
 686 err_drop_auth:
 687         crypto_drop_ahash(&ctx->auth);
 688 err_free_inst:
 689         kfree(inst);
 690 out_put_auth:
 691         inst = ERR_PTR(err);
 692         goto out;
 693 }
 694
 695 static void crypto_authenc_free(struct crypto_instance *inst)
 696 {
 697         struct authenc_instance_ctx *ctx = crypto_instance_ctx(inst);
 698
 699         crypto_drop_skcipher(&ctx->enc);
 700         crypto_drop_ahash(&ctx->auth);
 701         kfree(inst);
 702 }
 703
 704 static struct crypto_template crypto_authenc_tmpl = {
 705         .name = "authenc",
 706         .alloc = crypto_authenc_alloc,
 707         .free = crypto_authenc_free,
 708         .module = THIS_MODULE,
 709 };
 710
 711 static int __init crypto_authenc_module_init(void)
 712 {
 713         return crypto_register_template(&crypto_authenc_tmpl);
 714 }
 715
 716 static void __exit crypto_authenc_module_exit(void)
 717 {
 718         crypto_unregister_template(&crypto_authenc_tmpl);
 719 }
 720
 721 module_init(crypto_authenc_module_init);
 722 module_exit(crypto_authenc_module_exit);
 723
 724 MODULE_LICENSE("GPL");
 725 MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");