crypto/authencesn.c

   1 /*
   2  * authencesn.c - AEAD wrapper for IPsec with extended sequence numbers,
   3  *                 derived from authenc.c
   4  *
   5  * Copyright (C) 2010 secunet Security Networks AG
   6  * Copyright (C) 2010 Steffen Klassert <steffen.klassert@secunet.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the Free
  10  * Software Foundation; either version 2 of the License, or (at your option)
  11  * any later version.
  12  *
  13  */
  14
  15 #include <crypto/internal/aead.h>
  16 #include <crypto/internal/hash.h>
  17 #include <crypto/internal/skcipher.h>
  18 #include <crypto/authenc.h>
  19 #include <crypto/scatterwalk.h>
  20 #include <linux/err.h>
  21 #include <linux/init.h>
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/rtnetlink.h>
  25 #include <linux/slab.h>
  26 #include <linux/spinlock.h>
  27
  28 struct authenc_esn_instance_ctx {
  29         struct crypto_ahash_spawn auth;
  30         struct crypto_skcipher_spawn enc;
  31 };
  32
  33 struct crypto_authenc_esn_ctx {
  34         unsigned int reqoff;
  35         struct crypto_ahash *auth;
  36         struct crypto_ablkcipher *enc;
  37 };
  38
  39 struct authenc_esn_request_ctx {
  40         unsigned int cryptlen;
  41         unsigned int headlen;
  42         unsigned int trailen;
  43         struct scatterlist *sg;
  44         struct scatterlist hsg[2];
  45         struct scatterlist tsg[1];
  46         struct scatterlist cipher[2];
  47         crypto_completion_t complete;
  48         crypto_completion_t update_complete;
  49         crypto_completion_t update_complete2;
  50         char tail[];
  51 };
  52
  53 static void authenc_esn_request_complete(struct aead_request *req, int err)
  54 {
  55         if (err != -EINPROGRESS)
  56                 aead_request_complete(req, err);
  57 }
  58
  59 static int crypto_authenc_esn_setkey(struct crypto_aead *authenc_esn, const u8 *key,
  60                                      unsigned int keylen)
  61 {
  62         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
  63         struct crypto_ahash *auth = ctx->auth;
  64         struct crypto_ablkcipher *enc = ctx->enc;
  65         struct crypto_authenc_keys keys;
  66         int err = -EINVAL;
  67
  68         if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
  69                 goto badkey;
  70
  71         crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
  72         crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc_esn) &
  73                                      CRYPTO_TFM_REQ_MASK);
  74         err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
  75         crypto_aead_set_flags(authenc_esn, crypto_ahash_get_flags(auth) &
  76                                            CRYPTO_TFM_RES_MASK);
  77
  78         if (err)
  79                 goto out;
  80
  81         crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
  82         crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc_esn) &
  83                                          CRYPTO_TFM_REQ_MASK);
  84         err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen);
  85         crypto_aead_set_flags(authenc_esn, crypto_ablkcipher_get_flags(enc) &
  86                                            CRYPTO_TFM_RES_MASK);
  87
  88 out:
  89         return err;
  90
  91 badkey:
  92         crypto_aead_set_flags(authenc_esn, CRYPTO_TFM_RES_BAD_KEY_LEN);
  93         goto out;
  94 }
  95
  96 static void authenc_esn_geniv_ahash_update_done(struct crypto_async_request *areq,
  97                                                 int err)
  98 {
  99         struct aead_request *req = areq->data;
 100         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 101         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 102         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 103         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 104
 105         if (err)
 106                 goto out;
 107
 108         ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
 109                                 areq_ctx->cryptlen);
 110         ahash_request_set_callback(ahreq, aead_request_flags(req) &
 111                                           CRYPTO_TFM_REQ_MAY_SLEEP,
 112                                    areq_ctx->update_complete2, req);
 113
 114         err = crypto_ahash_update(ahreq);
 115         if (err)
 116                 goto out;
 117
 118         ahash_request_set_crypt(ahreq, areq_ctx->tsg, ahreq->result,
 119                                 areq_ctx->trailen);
 120         ahash_request_set_callback(ahreq, aead_request_flags(req) &
 121                                           CRYPTO_TFM_REQ_MAY_SLEEP,
 122                                    areq_ctx->complete, req);
 123
 124         err = crypto_ahash_finup(ahreq);
 125         if (err)
 126                 goto out;
 127
 128         scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
 129                                  areq_ctx->cryptlen,
 130                                  crypto_aead_authsize(authenc_esn), 1);
 131
 132 out:
 133         authenc_esn_request_complete(req, err);
 134 }
 135
 136 static void authenc_esn_geniv_ahash_update_done2(struct crypto_async_request *areq,
 137                                                  int err)
 138 {
 139         struct aead_request *req = areq->data;
 140         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 141         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 142         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 143         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 144
 145         if (err)
 146                 goto out;
 147
 148         ahash_request_set_crypt(ahreq, areq_ctx->tsg, ahreq->result,
 149                                 areq_ctx->trailen);
 150         ahash_request_set_callback(ahreq, aead_request_flags(req) &
 151                                           CRYPTO_TFM_REQ_MAY_SLEEP,
 152                                    areq_ctx->complete, req);
 153
 154         err = crypto_ahash_finup(ahreq);
 155         if (err)
 156                 goto out;
 157
 158         scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
 159                                  areq_ctx->cryptlen,
 160                                  crypto_aead_authsize(authenc_esn), 1);
 161
 162 out:
 163         authenc_esn_request_complete(req, err);
 164 }
 165
 166
 167 static void authenc_esn_geniv_ahash_done(struct crypto_async_request *areq,
 168                                          int err)
 169 {
 170         struct aead_request *req = areq->data;
 171         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 172         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 173         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 174         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 175
 176         if (err)
 177                 goto out;
 178
 179         scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
 180                                  areq_ctx->cryptlen,
 181                                  crypto_aead_authsize(authenc_esn), 1);
 182
 183 out:
 184         aead_request_complete(req, err);
 185 }
 186
 187
 188 static void authenc_esn_verify_ahash_update_done(struct crypto_async_request *areq,
 189                                                  int err)
 190 {
 191         u8 *ihash;
 192         unsigned int authsize;
 193         struct ablkcipher_request *abreq;
 194         struct aead_request *req = areq->data;
 195         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 196         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 197         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 198         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 199         unsigned int cryptlen = req->cryptlen;
 200
 201         if (err)
 202                 goto out;
 203
 204         ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
 205                                 areq_ctx->cryptlen);
 206
 207         ahash_request_set_callback(ahreq,
 208                                    aead_request_flags(req) &
 209                                    CRYPTO_TFM_REQ_MAY_SLEEP,
 210                                    areq_ctx->update_complete2, req);
 211
 212         err = crypto_ahash_update(ahreq);
 213         if (err)
 214                 goto out;
 215
 216         ahash_request_set_crypt(ahreq, areq_ctx->tsg, ahreq->result,
 217                                 areq_ctx->trailen);
 218         ahash_request_set_callback(ahreq, aead_request_flags(req) &
 219                                           CRYPTO_TFM_REQ_MAY_SLEEP,
 220                                    areq_ctx->complete, req);
 221
 222         err = crypto_ahash_finup(ahreq);
 223         if (err)
 224                 goto out;
 225
 226         authsize = crypto_aead_authsize(authenc_esn);
 227         cryptlen -= authsize;
 228         ihash = ahreq->result + authsize;
 229         scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
 230                                  authsize, 0);
 231
 232         err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
 233         if (err)
 234                 goto out;
 235
 236         abreq = aead_request_ctx(req);
 237         ablkcipher_request_set_tfm(abreq, ctx->enc);
 238         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 239                                         req->base.complete, req->base.data);
 240         ablkcipher_request_set_crypt(abreq, req->src, req->dst,
 241                                      cryptlen, req->iv);
 242
 243         err = crypto_ablkcipher_decrypt(abreq);
 244
 245 out:
 246         authenc_esn_request_complete(req, err);
 247 }
 248
 249 static void authenc_esn_verify_ahash_update_done2(struct crypto_async_request *areq,
 250                                                   int err)
 251 {
 252         u8 *ihash;
 253         unsigned int authsize;
 254         struct ablkcipher_request *abreq;
 255         struct aead_request *req = areq->data;
 256         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 257         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 258         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 259         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 260         unsigned int cryptlen = req->cryptlen;
 261
 262         if (err)
 263                 goto out;
 264
 265         ahash_request_set_crypt(ahreq, areq_ctx->tsg, ahreq->result,
 266                                 areq_ctx->trailen);
 267         ahash_request_set_callback(ahreq, aead_request_flags(req) &
 268                                           CRYPTO_TFM_REQ_MAY_SLEEP,
 269                                    areq_ctx->complete, req);
 270
 271         err = crypto_ahash_finup(ahreq);
 272         if (err)
 273                 goto out;
 274
 275         authsize = crypto_aead_authsize(authenc_esn);
 276         cryptlen -= authsize;
 277         ihash = ahreq->result + authsize;
 278         scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
 279                                  authsize, 0);
 280
 281         err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
 282         if (err)
 283                 goto out;
 284
 285         abreq = aead_request_ctx(req);
 286         ablkcipher_request_set_tfm(abreq, ctx->enc);
 287         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 288                                         req->base.complete, req->base.data);
 289         ablkcipher_request_set_crypt(abreq, req->src, req->dst,
 290                                      cryptlen, req->iv);
 291
 292         err = crypto_ablkcipher_decrypt(abreq);
 293
 294 out:
 295         authenc_esn_request_complete(req, err);
 296 }
 297
 298
 299 static void authenc_esn_verify_ahash_done(struct crypto_async_request *areq,
 300                                           int err)
 301 {
 302         u8 *ihash;
 303         unsigned int authsize;
 304         struct ablkcipher_request *abreq;
 305         struct aead_request *req = areq->data;
 306         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 307         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 308         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 309         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 310         unsigned int cryptlen = req->cryptlen;
 311
 312         if (err)
 313                 goto out;
 314
 315         authsize = crypto_aead_authsize(authenc_esn);
 316         cryptlen -= authsize;
 317         ihash = ahreq->result + authsize;
 318         scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
 319                                  authsize, 0);
 320
 321         err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
 322         if (err)
 323                 goto out;
 324
 325         abreq = aead_request_ctx(req);
 326         ablkcipher_request_set_tfm(abreq, ctx->enc);
 327         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 328                                         req->base.complete, req->base.data);
 329         ablkcipher_request_set_crypt(abreq, req->src, req->dst,
 330                                      cryptlen, req->iv);
 331
 332         err = crypto_ablkcipher_decrypt(abreq);
 333
 334 out:
 335         authenc_esn_request_complete(req, err);
 336 }
 337
 338 static u8 *crypto_authenc_esn_ahash(struct aead_request *req,
 339                                     unsigned int flags)
 340 {
 341         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 342         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 343         struct crypto_ahash *auth = ctx->auth;
 344         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 345         struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
 346         u8 *hash = areq_ctx->tail;
 347         int err;
 348
 349         hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
 350                             crypto_ahash_alignmask(auth) + 1);
 351
 352         ahash_request_set_tfm(ahreq, auth);
 353
 354         err = crypto_ahash_init(ahreq);
 355         if (err)
 356                 return ERR_PTR(err);
 357
 358         ahash_request_set_crypt(ahreq, areq_ctx->hsg, hash, areq_ctx->headlen);
 359         ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
 360                                    areq_ctx->update_complete, req);
 361
 362         err = crypto_ahash_update(ahreq);
 363         if (err)
 364                 return ERR_PTR(err);
 365
 366         ahash_request_set_crypt(ahreq, areq_ctx->sg, hash, areq_ctx->cryptlen);
 367         ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
 368                                    areq_ctx->update_complete2, req);
 369
 370         err = crypto_ahash_update(ahreq);
 371         if (err)
 372                 return ERR_PTR(err);
 373
 374         ahash_request_set_crypt(ahreq, areq_ctx->tsg, hash,
 375                                 areq_ctx->trailen);
 376         ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
 377                                    areq_ctx->complete, req);
 378
 379         err = crypto_ahash_finup(ahreq);
 380         if (err)
 381                 return ERR_PTR(err);
 382
 383         return hash;
 384 }
 385
 386 static int crypto_authenc_esn_genicv(struct aead_request *req, u8 *iv,
 387                                      unsigned int flags)
 388 {
 389         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 390         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 391         struct scatterlist *dst = req->dst;
 392         struct scatterlist *assoc = req->assoc;
 393         struct scatterlist *cipher = areq_ctx->cipher;
 394         struct scatterlist *hsg = areq_ctx->hsg;
 395         struct scatterlist *tsg = areq_ctx->tsg;
 396         struct scatterlist *assoc1;
 397         struct scatterlist *assoc2;
 398         unsigned int ivsize = crypto_aead_ivsize(authenc_esn);
 399         unsigned int cryptlen = req->cryptlen;
 400         struct page *dstp;
 401         u8 *vdst;
 402         u8 *hash;
 403
 404         dstp = sg_page(dst);
 405         vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset;
 406
 407         if (ivsize) {
 408                 sg_init_table(cipher, 2);
 409                 sg_set_buf(cipher, iv, ivsize);
 410                 scatterwalk_crypto_chain(cipher, dst, vdst == iv + ivsize, 2);
 411                 dst = cipher;
 412                 cryptlen += ivsize;
 413         }
 414
 415         if (sg_is_last(assoc))
 416                 return -EINVAL;
 417
 418         assoc1 = assoc + 1;
 419         if (sg_is_last(assoc1))
 420                 return -EINVAL;
 421
 422         assoc2 = assoc + 2;
 423         if (!sg_is_last(assoc2))
 424                 return -EINVAL;
 425
 426         sg_init_table(hsg, 2);
 427         sg_set_page(hsg, sg_page(assoc), assoc->length, assoc->offset);
 428         sg_set_page(hsg + 1, sg_page(assoc2), assoc2->length, assoc2->offset);
 429
 430         sg_init_table(tsg, 1);
 431         sg_set_page(tsg, sg_page(assoc1), assoc1->length, assoc1->offset);
 432
 433         areq_ctx->cryptlen = cryptlen;
 434         areq_ctx->headlen = assoc->length + assoc2->length;
 435         areq_ctx->trailen = assoc1->length;
 436         areq_ctx->sg = dst;
 437
 438         areq_ctx->complete = authenc_esn_geniv_ahash_done;
 439         areq_ctx->update_complete = authenc_esn_geniv_ahash_update_done;
 440         areq_ctx->update_complete2 = authenc_esn_geniv_ahash_update_done2;
 441
 442         hash = crypto_authenc_esn_ahash(req, flags);
 443         if (IS_ERR(hash))
 444                 return PTR_ERR(hash);
 445
 446         scatterwalk_map_and_copy(hash, dst, cryptlen,
 447                                  crypto_aead_authsize(authenc_esn), 1);
 448         return 0;
 449 }
 450
 451
 452 static void crypto_authenc_esn_encrypt_done(struct crypto_async_request *req,
 453                                             int err)
 454 {
 455         struct aead_request *areq = req->data;
 456
 457         if (!err) {
 458                 struct crypto_aead *authenc_esn = crypto_aead_reqtfm(areq);
 459                 struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 460                 struct ablkcipher_request *abreq = aead_request_ctx(areq);
 461                 u8 *iv = (u8 *)(abreq + 1) +
 462                          crypto_ablkcipher_reqsize(ctx->enc);
 463
 464                 err = crypto_authenc_esn_genicv(areq, iv, 0);
 465         }
 466
 467         authenc_esn_request_complete(areq, err);
 468 }
 469
 470 static int crypto_authenc_esn_encrypt(struct aead_request *req)
 471 {
 472         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 473         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 474         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 475         struct crypto_ablkcipher *enc = ctx->enc;
 476         struct scatterlist *dst = req->dst;
 477         unsigned int cryptlen = req->cryptlen;
 478         struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
 479                                                     + ctx->reqoff);
 480         u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(enc);
 481         int err;
 482
 483         ablkcipher_request_set_tfm(abreq, enc);
 484         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 485                                         crypto_authenc_esn_encrypt_done, req);
 486         ablkcipher_request_set_crypt(abreq, req->src, dst, cryptlen, req->iv);
 487
 488         memcpy(iv, req->iv, crypto_aead_ivsize(authenc_esn));
 489
 490         err = crypto_ablkcipher_encrypt(abreq);
 491         if (err)
 492                 return err;
 493
 494         return crypto_authenc_esn_genicv(req, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
 495 }
 496
 497 static void crypto_authenc_esn_givencrypt_done(struct crypto_async_request *req,
 498                                                int err)
 499 {
 500         struct aead_request *areq = req->data;
 501
 502         if (!err) {
 503                 struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
 504
 505                 err = crypto_authenc_esn_genicv(areq, greq->giv, 0);
 506         }
 507
 508         authenc_esn_request_complete(areq, err);
 509 }
 510
 511 static int crypto_authenc_esn_givencrypt(struct aead_givcrypt_request *req)
 512 {
 513         struct crypto_aead *authenc_esn = aead_givcrypt_reqtfm(req);
 514         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 515         struct aead_request *areq = &req->areq;
 516         struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
 517         u8 *iv = req->giv;
 518         int err;
 519
 520         skcipher_givcrypt_set_tfm(greq, ctx->enc);
 521         skcipher_givcrypt_set_callback(greq, aead_request_flags(areq),
 522                                        crypto_authenc_esn_givencrypt_done, areq);
 523         skcipher_givcrypt_set_crypt(greq, areq->src, areq->dst, areq->cryptlen,
 524                                     areq->iv);
 525         skcipher_givcrypt_set_giv(greq, iv, req->seq);
 526
 527         err = crypto_skcipher_givencrypt(greq);
 528         if (err)
 529                 return err;
 530
 531         return crypto_authenc_esn_genicv(areq, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
 532 }
 533
 534 static int crypto_authenc_esn_verify(struct aead_request *req)
 535 {
 536         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 537         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 538         u8 *ohash;
 539         u8 *ihash;
 540         unsigned int authsize;
 541
 542         areq_ctx->complete = authenc_esn_verify_ahash_done;
 543         areq_ctx->update_complete = authenc_esn_verify_ahash_update_done;
 544
 545         ohash = crypto_authenc_esn_ahash(req, CRYPTO_TFM_REQ_MAY_SLEEP);
 546         if (IS_ERR(ohash))
 547                 return PTR_ERR(ohash);
 548
 549         authsize = crypto_aead_authsize(authenc_esn);
 550         ihash = ohash + authsize;
 551         scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
 552                                  authsize, 0);
 553         return crypto_memneq(ihash, ohash, authsize) ? -EBADMSG : 0;
 554 }
 555
 556 static int crypto_authenc_esn_iverify(struct aead_request *req, u8 *iv,
 557                                       unsigned int cryptlen)
 558 {
 559         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 560         struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
 561         struct scatterlist *src = req->src;
 562         struct scatterlist *assoc = req->assoc;
 563         struct scatterlist *cipher = areq_ctx->cipher;
 564         struct scatterlist *hsg = areq_ctx->hsg;
 565         struct scatterlist *tsg = areq_ctx->tsg;
 566         struct scatterlist *assoc1;
 567         struct scatterlist *assoc2;
 568         unsigned int ivsize = crypto_aead_ivsize(authenc_esn);
 569         struct page *srcp;
 570         u8 *vsrc;
 571
 572         srcp = sg_page(src);
 573         vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
 574
 575         if (ivsize) {
 576                 sg_init_table(cipher, 2);
 577                 sg_set_buf(cipher, iv, ivsize);
 578                 scatterwalk_crypto_chain(cipher, src, vsrc == iv + ivsize, 2);
 579                 src = cipher;
 580                 cryptlen += ivsize;
 581         }
 582
 583         if (sg_is_last(assoc))
 584                 return -EINVAL;
 585
 586         assoc1 = assoc + 1;
 587         if (sg_is_last(assoc1))
 588                 return -EINVAL;
 589
 590         assoc2 = assoc + 2;
 591         if (!sg_is_last(assoc2))
 592                 return -EINVAL;
 593
 594         sg_init_table(hsg, 2);
 595         sg_set_page(hsg, sg_page(assoc), assoc->length, assoc->offset);
 596         sg_set_page(hsg + 1, sg_page(assoc2), assoc2->length, assoc2->offset);
 597
 598         sg_init_table(tsg, 1);
 599         sg_set_page(tsg, sg_page(assoc1), assoc1->length, assoc1->offset);
 600
 601         areq_ctx->cryptlen = cryptlen;
 602         areq_ctx->headlen = assoc->length + assoc2->length;
 603         areq_ctx->trailen = assoc1->length;
 604         areq_ctx->sg = src;
 605
 606         areq_ctx->complete = authenc_esn_verify_ahash_done;
 607         areq_ctx->update_complete = authenc_esn_verify_ahash_update_done;
 608         areq_ctx->update_complete2 = authenc_esn_verify_ahash_update_done2;
 609
 610         return crypto_authenc_esn_verify(req);
 611 }
 612
 613 static int crypto_authenc_esn_decrypt(struct aead_request *req)
 614 {
 615         struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
 616         struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
 617         struct ablkcipher_request *abreq = aead_request_ctx(req);
 618         unsigned int cryptlen = req->cryptlen;
 619         unsigned int authsize = crypto_aead_authsize(authenc_esn);
 620         u8 *iv = req->iv;
 621         int err;
 622
 623         if (cryptlen < authsize)
 624                 return -EINVAL;
 625         cryptlen -= authsize;
 626
 627         err = crypto_authenc_esn_iverify(req, iv, cryptlen);
 628         if (err)
 629                 return err;
 630
 631         ablkcipher_request_set_tfm(abreq, ctx->enc);
 632         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 633                                         req->base.complete, req->base.data);
 634         ablkcipher_request_set_crypt(abreq, req->src, req->dst, cryptlen, iv);
 635
 636         return crypto_ablkcipher_decrypt(abreq);
 637 }
 638
 639 static int crypto_authenc_esn_init_tfm(struct crypto_tfm *tfm)
 640 {
 641         struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
 642         struct authenc_esn_instance_ctx *ictx = crypto_instance_ctx(inst);
 643         struct crypto_authenc_esn_ctx *ctx = crypto_tfm_ctx(tfm);
 644         struct crypto_ahash *auth;
 645         struct crypto_ablkcipher *enc;
 646         int err;
 647
 648         auth = crypto_spawn_ahash(&ictx->auth);
 649         if (IS_ERR(auth))
 650                 return PTR_ERR(auth);
 651
 652         enc = crypto_spawn_skcipher(&ictx->enc);
 653         err = PTR_ERR(enc);
 654         if (IS_ERR(enc))
 655                 goto err_free_ahash;
 656
 657         ctx->auth = auth;
 658         ctx->enc = enc;
 659
 660         ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) +
 661                             crypto_ahash_alignmask(auth),
 662                             crypto_ahash_alignmask(auth) + 1) +
 663                       crypto_ablkcipher_ivsize(enc);
 664
 665         crypto_aead_set_reqsize(__crypto_aead_cast(tfm),
 666                 sizeof(struct authenc_esn_request_ctx) +
 667                 ctx->reqoff +
 668                 max_t(unsigned int,
 669                         crypto_ahash_reqsize(auth) +
 670                         sizeof(struct ahash_request),
 671                         sizeof(struct skcipher_givcrypt_request) +
 672                         crypto_ablkcipher_reqsize(enc)));
 673
 674         return 0;
 675
 676 err_free_ahash:
 677         crypto_free_ahash(auth);
 678         return err;
 679 }
 680
 681 static void crypto_authenc_esn_exit_tfm(struct crypto_tfm *tfm)
 682 {
 683         struct crypto_authenc_esn_ctx *ctx = crypto_tfm_ctx(tfm);
 684
 685         crypto_free_ahash(ctx->auth);
 686         crypto_free_ablkcipher(ctx->enc);
 687 }
 688
 689 static struct crypto_instance *crypto_authenc_esn_alloc(struct rtattr **tb)
 690 {
 691         struct crypto_attr_type *algt;
 692         struct crypto_instance *inst;
 693         struct hash_alg_common *auth;
 694         struct crypto_alg *auth_base;
 695         struct crypto_alg *enc;
 696         struct authenc_esn_instance_ctx *ctx;
 697         const char *enc_name;
 698         int err;
 699
 700         algt = crypto_get_attr_type(tb);
 701         if (IS_ERR(algt))
 702                 return ERR_CAST(algt);
 703
 704         if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
 705                 return ERR_PTR(-EINVAL);
 706
 707         auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
 708                                CRYPTO_ALG_TYPE_AHASH_MASK);
 709         if (IS_ERR(auth))
 710                 return ERR_CAST(auth);
 711
 712         auth_base = &auth->base;
 713
 714         enc_name = crypto_attr_alg_name(tb[2]);
 715         err = PTR_ERR(enc_name);
 716         if (IS_ERR(enc_name))
 717                 goto out_put_auth;
 718
 719         inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
 720         err = -ENOMEM;
 721         if (!inst)
 722                 goto out_put_auth;
 723
 724         ctx = crypto_instance_ctx(inst);
 725
 726         err = crypto_init_ahash_spawn(&ctx->auth, auth, inst);
 727         if (err)
 728                 goto err_free_inst;
 729
 730         crypto_set_skcipher_spawn(&ctx->enc, inst);
 731         err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
 732                                    crypto_requires_sync(algt->type,
 733                                                         algt->mask));
 734         if (err)
 735                 goto err_drop_auth;
 736
 737         enc = crypto_skcipher_spawn_alg(&ctx->enc);
 738
 739         err = -ENAMETOOLONG;
 740         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
 741                      "authencesn(%s,%s)", auth_base->cra_name, enc->cra_name) >=
 742             CRYPTO_MAX_ALG_NAME)
 743                 goto err_drop_enc;
 744
 745         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
 746                      "authencesn(%s,%s)", auth_base->cra_driver_name,
 747                      enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 748                 goto err_drop_enc;
 749
 750         inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
 751         inst->alg.cra_flags |= enc->cra_flags & CRYPTO_ALG_ASYNC;
 752         inst->alg.cra_priority = enc->cra_priority *
 753                                  10 + auth_base->cra_priority;
 754         inst->alg.cra_blocksize = enc->cra_blocksize;
 755         inst->alg.cra_alignmask = auth_base->cra_alignmask | enc->cra_alignmask;
 756         inst->alg.cra_type = &crypto_aead_type;
 757
 758         inst->alg.cra_aead.ivsize = enc->cra_ablkcipher.ivsize;
 759         inst->alg.cra_aead.maxauthsize = auth->digestsize;
 760
 761         inst->alg.cra_ctxsize = sizeof(struct crypto_authenc_esn_ctx);
 762
 763         inst->alg.cra_init = crypto_authenc_esn_init_tfm;
 764         inst->alg.cra_exit = crypto_authenc_esn_exit_tfm;
 765
 766         inst->alg.cra_aead.setkey = crypto_authenc_esn_setkey;
 767         inst->alg.cra_aead.encrypt = crypto_authenc_esn_encrypt;
 768         inst->alg.cra_aead.decrypt = crypto_authenc_esn_decrypt;
 769         inst->alg.cra_aead.givencrypt = crypto_authenc_esn_givencrypt;
 770
 771 out:
 772         crypto_mod_put(auth_base);
 773         return inst;
 774
 775 err_drop_enc:
 776         crypto_drop_skcipher(&ctx->enc);
 777 err_drop_auth:
 778         crypto_drop_ahash(&ctx->auth);
 779 err_free_inst:
 780         kfree(inst);
 781 out_put_auth:
 782         inst = ERR_PTR(err);
 783         goto out;
 784 }
 785
 786 static void crypto_authenc_esn_free(struct crypto_instance *inst)
 787 {
 788         struct authenc_esn_instance_ctx *ctx = crypto_instance_ctx(inst);
 789
 790         crypto_drop_skcipher(&ctx->enc);
 791         crypto_drop_ahash(&ctx->auth);
 792         kfree(inst);
 793 }
 794
 795 static struct crypto_template crypto_authenc_esn_tmpl = {
 796         .name = "authencesn",
 797         .alloc = crypto_authenc_esn_alloc,
 798         .free = crypto_authenc_esn_free,
 799         .module = THIS_MODULE,
 800 };
 801
 802 static int __init crypto_authenc_esn_module_init(void)
 803 {
 804         return crypto_register_template(&crypto_authenc_esn_tmpl);
 805 }
 806
 807 static void __exit crypto_authenc_esn_module_exit(void)
 808 {
 809         crypto_unregister_template(&crypto_authenc_esn_tmpl);
 810 }
 811
 812 module_init(crypto_authenc_esn_module_init);
 813 module_exit(crypto_authenc_esn_module_exit);
 814
 815 MODULE_LICENSE("GPL");
 816 MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
 817 MODULE_DESCRIPTION("AEAD wrapper for IPsec with extended sequence numbers");
 818 MODULE_ALIAS_CRYPTO("authencesn");