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 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 96 out: 97 return err; 98 99 badkey: 100 crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN); 101 goto out; 102 } 103 104 static 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 } 117 118 static 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); 143 144 out: 145 aead_request_complete(req, err); 146 } 147 148 static 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); 162 163 out: 164 aead_request_complete(req, err); 165 } 166 167 static 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); 209 210 out: 211 aead_request_complete(req, err); 212 } 213 214 static 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); 246 247 out: 248 aead_request_complete(req, err); 249 } 250 251 static 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 } 289 290 static 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 } 315 316 static 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 } 366 367 static 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 } 384 385 static 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 } 409 410 static 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 } 423 424 static 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 } 446 447 static 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 } 469 470 static 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 } 509 510 static 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 } 535 536 static 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; 570 571 err_free_ahash: 572 crypto_free_ahash(auth); 573 return err; 574 } 575 576 static 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 } 583 584 static 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; 666 667 out: 668 crypto_mod_put(auth_base); 669 return inst; 670 671 err_drop_enc: 672 crypto_drop_skcipher(&ctx->enc); 673 err_drop_auth: 674 crypto_drop_ahash(&ctx->auth); 675 err_free_inst: 676 kfree(inst); 677 out_put_auth: 678 inst = ERR_PTR(err); 679 goto out; 680 } 681 682 static 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 } 690 691 static struct crypto_template crypto_authenc_tmpl = { 692 .name = "authenc", 693 .alloc = crypto_authenc_alloc, 694 .free = crypto_authenc_free, 695 .module = THIS_MODULE, 696 }; 697 698 static int __init crypto_authenc_module_init(void) 699 { 700 return crypto_register_template(&crypto_authenc_tmpl); 701 } 702 703 static void __exit crypto_authenc_module_exit(void) 704 { 705 crypto_unregister_template(&crypto_authenc_tmpl); 706 } 707 708 module_init(crypto_authenc_module_init); 709 module_exit(crypto_authenc_module_exit); 710 711 MODULE_LICENSE("GPL"); 712 MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec"); 713