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 int 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
  66         /*
  67          * RTA_OK() didn't align the rtattr's payload when validating that it
  68          * fits in the buffer.  Yet, the keys should start on the next 4-byte
  69          * aligned boundary.  To avoid confusion, require that the rtattr
  70          * payload be exactly the param struct, which has a 4-byte aligned size.
  71          */
  72         if (RTA_PAYLOAD(rta) != sizeof(*param))
  73                 return -EINVAL;
  74         BUILD_BUG_ON(sizeof(*param) % RTA_ALIGNTO);
  75
  76         param = RTA_DATA(rta);
  77         keys->enckeylen = be32_to_cpu(param->enckeylen);
  78
  79         key += rta->rta_len;
  80         keylen -= rta->rta_len;
  81
  82         if (keylen < keys->enckeylen)
  83                 return -EINVAL;
  84
  85         keys->authkeylen = keylen - keys->enckeylen;
  86         keys->authkey = key;
  87         keys->enckey = key + keys->authkeylen;
  88
  89         return 0;
  90 }
  91 EXPORT_SYMBOL_GPL(crypto_authenc_extractkeys);
  92
  93 static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
  94                                  unsigned int keylen)
  95 {
  96         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
  97         struct crypto_ahash *auth = ctx->auth;
  98         struct crypto_ablkcipher *enc = ctx->enc;
  99         struct crypto_authenc_keys keys;
 100         int err = -EINVAL;
 101
 102         if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
 103                 goto badkey;
 104
 105         crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
 106         crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) &
 107                                     CRYPTO_TFM_REQ_MASK);
 108         err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
 109         crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) &
 110                                        CRYPTO_TFM_RES_MASK);
 111
 112         if (err)
 113                 goto out;
 114
 115         crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
 116         crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
 117                                          CRYPTO_TFM_REQ_MASK);
 118         err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen);
 119         crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) &
 120                                        CRYPTO_TFM_RES_MASK);
 121
 122 out:
 123         return err;
 124
 125 badkey:
 126         crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN);
 127         goto out;
 128 }
 129
 130 static void authenc_geniv_ahash_update_done(struct crypto_async_request *areq,
 131                                             int err)
 132 {
 133         struct aead_request *req = areq->data;
 134         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 135         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 136         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 137         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 138
 139         if (err)
 140                 goto out;
 141
 142         ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
 143                                 areq_ctx->cryptlen);
 144         ahash_request_set_callback(ahreq, aead_request_flags(req) &
 145                                           CRYPTO_TFM_REQ_MAY_SLEEP,
 146                                    areq_ctx->complete, req);
 147
 148         err = crypto_ahash_finup(ahreq);
 149         if (err)
 150                 goto out;
 151
 152         scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
 153                                  areq_ctx->cryptlen,
 154                                  crypto_aead_authsize(authenc), 1);
 155
 156 out:
 157         authenc_request_complete(req, err);
 158 }
 159
 160 static void authenc_geniv_ahash_done(struct crypto_async_request *areq, int err)
 161 {
 162         struct aead_request *req = areq->data;
 163         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 164         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 165         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 166         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 167
 168         if (err)
 169                 goto out;
 170
 171         scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
 172                                  areq_ctx->cryptlen,
 173                                  crypto_aead_authsize(authenc), 1);
 174
 175 out:
 176         aead_request_complete(req, err);
 177 }
 178
 179 static void authenc_verify_ahash_update_done(struct crypto_async_request *areq,
 180                                              int err)
 181 {
 182         u8 *ihash;
 183         unsigned int authsize;
 184         struct ablkcipher_request *abreq;
 185         struct aead_request *req = areq->data;
 186         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 187         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 188         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 189         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 190         unsigned int cryptlen = req->cryptlen;
 191
 192         if (err)
 193                 goto out;
 194
 195         ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
 196                                 areq_ctx->cryptlen);
 197         ahash_request_set_callback(ahreq, aead_request_flags(req) &
 198                                           CRYPTO_TFM_REQ_MAY_SLEEP,
 199                                    areq_ctx->complete, req);
 200
 201         err = crypto_ahash_finup(ahreq);
 202         if (err)
 203                 goto out;
 204
 205         authsize = crypto_aead_authsize(authenc);
 206         cryptlen -= authsize;
 207         ihash = ahreq->result + authsize;
 208         scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
 209                                  authsize, 0);
 210
 211         err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
 212         if (err)
 213                 goto out;
 214
 215         abreq = aead_request_ctx(req);
 216         ablkcipher_request_set_tfm(abreq, ctx->enc);
 217         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 218                                         req->base.complete, req->base.data);
 219         ablkcipher_request_set_crypt(abreq, req->src, req->dst,
 220                                      cryptlen, req->iv);
 221
 222         err = crypto_ablkcipher_decrypt(abreq);
 223
 224 out:
 225         authenc_request_complete(req, err);
 226 }
 227
 228 static void authenc_verify_ahash_done(struct crypto_async_request *areq,
 229                                       int err)
 230 {
 231         u8 *ihash;
 232         unsigned int authsize;
 233         struct ablkcipher_request *abreq;
 234         struct aead_request *req = areq->data;
 235         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 236         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 237         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 238         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 239         unsigned int cryptlen = req->cryptlen;
 240
 241         if (err)
 242                 goto out;
 243
 244         authsize = crypto_aead_authsize(authenc);
 245         cryptlen -= authsize;
 246         ihash = ahreq->result + authsize;
 247         scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
 248                                  authsize, 0);
 249
 250         err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
 251         if (err)
 252                 goto out;
 253
 254         abreq = aead_request_ctx(req);
 255         ablkcipher_request_set_tfm(abreq, ctx->enc);
 256         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 257                                         req->base.complete, req->base.data);
 258         ablkcipher_request_set_crypt(abreq, req->src, req->dst,
 259                                      cryptlen, req->iv);
 260
 261         err = crypto_ablkcipher_decrypt(abreq);
 262
 263 out:
 264         authenc_request_complete(req, err);
 265 }
 266
 267 static u8 *crypto_authenc_ahash_fb(struct aead_request *req, unsigned int flags)
 268 {
 269         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 270         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 271         struct crypto_ahash *auth = ctx->auth;
 272         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 273         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 274         u8 *hash = areq_ctx->tail;
 275         int err;
 276
 277         hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
 278                             crypto_ahash_alignmask(auth) + 1);
 279
 280         ahash_request_set_tfm(ahreq, auth);
 281
 282         err = crypto_ahash_init(ahreq);
 283         if (err)
 284                 return ERR_PTR(err);
 285
 286         ahash_request_set_crypt(ahreq, req->assoc, hash, req->assoclen);
 287         ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
 288                                    areq_ctx->update_complete, req);
 289
 290         err = crypto_ahash_update(ahreq);
 291         if (err)
 292                 return ERR_PTR(err);
 293
 294         ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
 295                                 areq_ctx->cryptlen);
 296         ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
 297                                    areq_ctx->complete, req);
 298
 299         err = crypto_ahash_finup(ahreq);
 300         if (err)
 301                 return ERR_PTR(err);
 302
 303         return hash;
 304 }
 305
 306 static u8 *crypto_authenc_ahash(struct aead_request *req, unsigned int flags)
 307 {
 308         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 309         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 310         struct crypto_ahash *auth = ctx->auth;
 311         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 312         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 313         u8 *hash = areq_ctx->tail;
 314         int err;
 315
 316         hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
 317                            crypto_ahash_alignmask(auth) + 1);
 318
 319         ahash_request_set_tfm(ahreq, auth);
 320         ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
 321                                 areq_ctx->cryptlen);
 322         ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
 323                                    areq_ctx->complete, req);
 324
 325         err = crypto_ahash_digest(ahreq);
 326         if (err)
 327                 return ERR_PTR(err);
 328
 329         return hash;
 330 }
 331
 332 static int crypto_authenc_genicv(struct aead_request *req, u8 *iv,
 333                                  unsigned int flags)
 334 {
 335         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 336         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 337         struct scatterlist *dst = req->dst;
 338         struct scatterlist *assoc = req->assoc;
 339         struct scatterlist *cipher = areq_ctx->cipher;
 340         struct scatterlist *asg = areq_ctx->asg;
 341         unsigned int ivsize = crypto_aead_ivsize(authenc);
 342         unsigned int cryptlen = req->cryptlen;
 343         authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
 344         struct page *dstp;
 345         u8 *vdst;
 346         u8 *hash;
 347
 348         dstp = sg_page(dst);
 349         vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset;
 350
 351         if (ivsize) {
 352                 sg_init_table(cipher, 2);
 353                 sg_set_buf(cipher, iv, ivsize);
 354                 scatterwalk_crypto_chain(cipher, dst, vdst == iv + ivsize, 2);
 355                 dst = cipher;
 356                 cryptlen += ivsize;
 357         }
 358
 359         if (req->assoclen && sg_is_last(assoc)) {
 360                 authenc_ahash_fn = crypto_authenc_ahash;
 361                 sg_init_table(asg, 2);
 362                 sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
 363                 scatterwalk_crypto_chain(asg, dst, 0, 2);
 364                 dst = asg;
 365                 cryptlen += req->assoclen;
 366         }
 367
 368         areq_ctx->cryptlen = cryptlen;
 369         areq_ctx->sg = dst;
 370
 371         areq_ctx->complete = authenc_geniv_ahash_done;
 372         areq_ctx->update_complete = authenc_geniv_ahash_update_done;
 373
 374         hash = authenc_ahash_fn(req, flags);
 375         if (IS_ERR(hash))
 376                 return PTR_ERR(hash);
 377
 378         scatterwalk_map_and_copy(hash, dst, cryptlen,
 379                                  crypto_aead_authsize(authenc), 1);
 380         return 0;
 381 }
 382
 383 static void crypto_authenc_encrypt_done(struct crypto_async_request *req,
 384                                         int err)
 385 {
 386         struct aead_request *areq = req->data;
 387
 388         if (!err) {
 389                 struct crypto_aead *authenc = crypto_aead_reqtfm(areq);
 390                 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 391                 struct authenc_request_ctx *areq_ctx = aead_request_ctx(areq);
 392                 struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
 393                                                             + ctx->reqoff);
 394                 u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(ctx->enc);
 395
 396                 err = crypto_authenc_genicv(areq, iv, 0);
 397         }
 398
 399         authenc_request_complete(areq, err);
 400 }
 401
 402 static int crypto_authenc_encrypt(struct aead_request *req)
 403 {
 404         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 405         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 406         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 407         struct crypto_ablkcipher *enc = ctx->enc;
 408         struct scatterlist *dst = req->dst;
 409         unsigned int cryptlen = req->cryptlen;
 410         struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
 411                                                     + ctx->reqoff);
 412         u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(enc);
 413         int err;
 414
 415         ablkcipher_request_set_tfm(abreq, enc);
 416         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 417                                         crypto_authenc_encrypt_done, req);
 418         ablkcipher_request_set_crypt(abreq, req->src, dst, cryptlen, req->iv);
 419
 420         memcpy(iv, req->iv, crypto_aead_ivsize(authenc));
 421
 422         err = crypto_ablkcipher_encrypt(abreq);
 423         if (err)
 424                 return err;
 425
 426         return crypto_authenc_genicv(req, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
 427 }
 428
 429 static void crypto_authenc_givencrypt_done(struct crypto_async_request *req,
 430                                            int err)
 431 {
 432         struct aead_request *areq = req->data;
 433
 434         if (!err) {
 435                 struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
 436
 437                 err = crypto_authenc_genicv(areq, greq->giv, 0);
 438         }
 439
 440         authenc_request_complete(areq, err);
 441 }
 442
 443 static int crypto_authenc_givencrypt(struct aead_givcrypt_request *req)
 444 {
 445         struct crypto_aead *authenc = aead_givcrypt_reqtfm(req);
 446         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 447         struct aead_request *areq = &req->areq;
 448         struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
 449         u8 *iv = req->giv;
 450         int err;
 451
 452         skcipher_givcrypt_set_tfm(greq, ctx->enc);
 453         skcipher_givcrypt_set_callback(greq, aead_request_flags(areq),
 454                                        crypto_authenc_givencrypt_done, areq);
 455         skcipher_givcrypt_set_crypt(greq, areq->src, areq->dst, areq->cryptlen,
 456                                     areq->iv);
 457         skcipher_givcrypt_set_giv(greq, iv, req->seq);
 458
 459         err = crypto_skcipher_givencrypt(greq);
 460         if (err)
 461                 return err;
 462
 463         return crypto_authenc_genicv(areq, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
 464 }
 465
 466 static int crypto_authenc_verify(struct aead_request *req,
 467                                  authenc_ahash_t authenc_ahash_fn)
 468 {
 469         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 470         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 471         u8 *ohash;
 472         u8 *ihash;
 473         unsigned int authsize;
 474
 475         areq_ctx->complete = authenc_verify_ahash_done;
 476         areq_ctx->update_complete = authenc_verify_ahash_update_done;
 477
 478         ohash = authenc_ahash_fn(req, CRYPTO_TFM_REQ_MAY_SLEEP);
 479         if (IS_ERR(ohash))
 480                 return PTR_ERR(ohash);
 481
 482         authsize = crypto_aead_authsize(authenc);
 483         ihash = ohash + authsize;
 484         scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
 485                                  authsize, 0);
 486         return crypto_memneq(ihash, ohash, authsize) ? -EBADMSG : 0;
 487 }
 488
 489 static int crypto_authenc_iverify(struct aead_request *req, u8 *iv,
 490                                   unsigned int cryptlen)
 491 {
 492         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 493         struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
 494         struct scatterlist *src = req->src;
 495         struct scatterlist *assoc = req->assoc;
 496         struct scatterlist *cipher = areq_ctx->cipher;
 497         struct scatterlist *asg = areq_ctx->asg;
 498         unsigned int ivsize = crypto_aead_ivsize(authenc);
 499         authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
 500         struct page *srcp;
 501         u8 *vsrc;
 502
 503         srcp = sg_page(src);
 504         vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
 505
 506         if (ivsize) {
 507                 sg_init_table(cipher, 2);
 508                 sg_set_buf(cipher, iv, ivsize);
 509                 scatterwalk_crypto_chain(cipher, src, vsrc == iv + ivsize, 2);
 510                 src = cipher;
 511                 cryptlen += ivsize;
 512         }
 513
 514         if (req->assoclen && sg_is_last(assoc)) {
 515                 authenc_ahash_fn = crypto_authenc_ahash;
 516                 sg_init_table(asg, 2);
 517                 sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
 518                 scatterwalk_crypto_chain(asg, src, 0, 2);
 519                 src = asg;
 520                 cryptlen += req->assoclen;
 521         }
 522
 523         areq_ctx->cryptlen = cryptlen;
 524         areq_ctx->sg = src;
 525
 526         return crypto_authenc_verify(req, authenc_ahash_fn);
 527 }
 528
 529 static int crypto_authenc_decrypt(struct aead_request *req)
 530 {
 531         struct crypto_aead *authenc = crypto_aead_reqtfm(req);
 532         struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
 533         struct ablkcipher_request *abreq = aead_request_ctx(req);
 534         unsigned int cryptlen = req->cryptlen;
 535         unsigned int authsize = crypto_aead_authsize(authenc);
 536         u8 *iv = req->iv;
 537         int err;
 538
 539         if (cryptlen < authsize)
 540                 return -EINVAL;
 541         cryptlen -= authsize;
 542
 543         err = crypto_authenc_iverify(req, iv, cryptlen);
 544         if (err)
 545                 return err;
 546
 547         ablkcipher_request_set_tfm(abreq, ctx->enc);
 548         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 549                                         req->base.complete, req->base.data);
 550         ablkcipher_request_set_crypt(abreq, req->src, req->dst, cryptlen, iv);
 551
 552         return crypto_ablkcipher_decrypt(abreq);
 553 }
 554
 555 static int crypto_authenc_init_tfm(struct crypto_tfm *tfm)
 556 {
 557         struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
 558         struct authenc_instance_ctx *ictx = crypto_instance_ctx(inst);
 559         struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
 560         struct crypto_ahash *auth;
 561         struct crypto_ablkcipher *enc;
 562         int err;
 563
 564         auth = crypto_spawn_ahash(&ictx->auth);
 565         if (IS_ERR(auth))
 566                 return PTR_ERR(auth);
 567
 568         enc = crypto_spawn_skcipher(&ictx->enc);
 569         err = PTR_ERR(enc);
 570         if (IS_ERR(enc))
 571                 goto err_free_ahash;
 572
 573         ctx->auth = auth;
 574         ctx->enc = enc;
 575
 576         ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) +
 577                             crypto_ahash_alignmask(auth),
 578                             crypto_ahash_alignmask(auth) + 1) +
 579                       crypto_ablkcipher_ivsize(enc);
 580
 581         tfm->crt_aead.reqsize = sizeof(struct authenc_request_ctx) +
 582                                 ctx->reqoff +
 583                                 max_t(unsigned int,
 584                                 crypto_ahash_reqsize(auth) +
 585                                 sizeof(struct ahash_request),
 586                                 sizeof(struct skcipher_givcrypt_request) +
 587                                 crypto_ablkcipher_reqsize(enc));
 588
 589         return 0;
 590
 591 err_free_ahash:
 592         crypto_free_ahash(auth);
 593         return err;
 594 }
 595
 596 static void crypto_authenc_exit_tfm(struct crypto_tfm *tfm)
 597 {
 598         struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
 599
 600         crypto_free_ahash(ctx->auth);
 601         crypto_free_ablkcipher(ctx->enc);
 602 }
 603
 604 static struct crypto_instance *crypto_authenc_alloc(struct rtattr **tb)
 605 {
 606         struct crypto_attr_type *algt;
 607         struct crypto_instance *inst;
 608         struct hash_alg_common *auth;
 609         struct crypto_alg *auth_base;
 610         struct crypto_alg *enc;
 611         struct authenc_instance_ctx *ctx;
 612         const char *enc_name;
 613         int err;
 614
 615         algt = crypto_get_attr_type(tb);
 616         if (IS_ERR(algt))
 617                 return ERR_CAST(algt);
 618
 619         if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
 620                 return ERR_PTR(-EINVAL);
 621
 622         auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
 623                                CRYPTO_ALG_TYPE_AHASH_MASK);
 624         if (IS_ERR(auth))
 625                 return ERR_CAST(auth);
 626
 627         auth_base = &auth->base;
 628
 629         enc_name = crypto_attr_alg_name(tb[2]);
 630         err = PTR_ERR(enc_name);
 631         if (IS_ERR(enc_name))
 632                 goto out_put_auth;
 633
 634         inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
 635         err = -ENOMEM;
 636         if (!inst)
 637                 goto out_put_auth;
 638
 639         ctx = crypto_instance_ctx(inst);
 640
 641         err = crypto_init_ahash_spawn(&ctx->auth, auth, inst);
 642         if (err)
 643                 goto err_free_inst;
 644
 645         crypto_set_skcipher_spawn(&ctx->enc, inst);
 646         err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
 647                                    crypto_requires_sync(algt->type,
 648                                                         algt->mask));
 649         if (err)
 650                 goto err_drop_auth;
 651
 652         enc = crypto_skcipher_spawn_alg(&ctx->enc);
 653
 654         err = -ENAMETOOLONG;
 655         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
 656                      "authenc(%s,%s)", auth_base->cra_name, enc->cra_name) >=
 657             CRYPTO_MAX_ALG_NAME)
 658                 goto err_drop_enc;
 659
 660         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
 661                      "authenc(%s,%s)", auth_base->cra_driver_name,
 662                      enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 663                 goto err_drop_enc;
 664
 665         inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
 666         inst->alg.cra_flags |= enc->cra_flags & CRYPTO_ALG_ASYNC;
 667         inst->alg.cra_priority = enc->cra_priority *
 668                                  10 + auth_base->cra_priority;
 669         inst->alg.cra_blocksize = enc->cra_blocksize;
 670         inst->alg.cra_alignmask = auth_base->cra_alignmask | enc->cra_alignmask;
 671         inst->alg.cra_type = &crypto_aead_type;
 672
 673         inst->alg.cra_aead.ivsize = enc->cra_ablkcipher.ivsize;
 674         inst->alg.cra_aead.maxauthsize = auth->digestsize;
 675
 676         inst->alg.cra_ctxsize = sizeof(struct crypto_authenc_ctx);
 677
 678         inst->alg.cra_init = crypto_authenc_init_tfm;
 679         inst->alg.cra_exit = crypto_authenc_exit_tfm;
 680
 681         inst->alg.cra_aead.setkey = crypto_authenc_setkey;
 682         inst->alg.cra_aead.encrypt = crypto_authenc_encrypt;
 683         inst->alg.cra_aead.decrypt = crypto_authenc_decrypt;
 684         inst->alg.cra_aead.givencrypt = crypto_authenc_givencrypt;
 685
 686 out:
 687         crypto_mod_put(auth_base);
 688         return inst;
 689
 690 err_drop_enc:
 691         crypto_drop_skcipher(&ctx->enc);
 692 err_drop_auth:
 693         crypto_drop_ahash(&ctx->auth);
 694 err_free_inst:
 695         kfree(inst);
 696 out_put_auth:
 697         inst = ERR_PTR(err);
 698         goto out;
 699 }
 700
 701 static void crypto_authenc_free(struct crypto_instance *inst)
 702 {
 703         struct authenc_instance_ctx *ctx = crypto_instance_ctx(inst);
 704
 705         crypto_drop_skcipher(&ctx->enc);
 706         crypto_drop_ahash(&ctx->auth);
 707         kfree(inst);
 708 }
 709
 710 static struct crypto_template crypto_authenc_tmpl = {
 711         .name = "authenc",
 712         .alloc = crypto_authenc_alloc,
 713         .free = crypto_authenc_free,
 714         .module = THIS_MODULE,
 715 };
 716
 717 static int __init crypto_authenc_module_init(void)
 718 {
 719         return crypto_register_template(&crypto_authenc_tmpl);
 720 }
 721
 722 static void __exit crypto_authenc_module_exit(void)
 723 {
 724         crypto_unregister_template(&crypto_authenc_tmpl);
 725 }
 726
 727 module_init(crypto_authenc_module_init);
 728 module_exit(crypto_authenc_module_exit);
 729
 730 MODULE_LICENSE("GPL");
 731 MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");
 732 MODULE_ALIAS_CRYPTO("authenc");