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