crypto/ccm.c

   1 /*
   2  * CCM: Counter with CBC-MAC
   3  *
   4  * (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
   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/internal/aead.h>
  14 #include <crypto/internal/hash.h>
  15 #include <crypto/internal/skcipher.h>
  16 #include <crypto/scatterwalk.h>
  17 #include <linux/err.h>
  18 #include <linux/init.h>
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21 #include <linux/slab.h>
  22
  23 #include "internal.h"
  24
  25 struct ccm_instance_ctx {
  26         struct crypto_skcipher_spawn ctr;
  27         struct crypto_ahash_spawn mac;
  28 };
  29
  30 struct crypto_ccm_ctx {
  31         struct crypto_ahash *mac;
  32         struct crypto_skcipher *ctr;
  33 };
  34
  35 struct crypto_rfc4309_ctx {
  36         struct crypto_aead *child;
  37         u8 nonce[3];
  38 };
  39
  40 struct crypto_rfc4309_req_ctx {
  41         struct scatterlist src[3];
  42         struct scatterlist dst[3];
  43         struct aead_request subreq;
  44 };
  45
  46 struct crypto_ccm_req_priv_ctx {
  47         u8 odata[16];
  48         u8 auth_tag[16];
  49         u32 flags;
  50         struct scatterlist src[3];
  51         struct scatterlist dst[3];
  52         struct skcipher_request skreq;
  53 };
  54
  55 struct cbcmac_tfm_ctx {
  56         struct crypto_cipher *child;
  57 };
  58
  59 struct cbcmac_desc_ctx {
  60         unsigned int len;
  61 };
  62
  63 static inline struct crypto_ccm_req_priv_ctx *crypto_ccm_reqctx(
  64         struct aead_request *req)
  65 {
  66         unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
  67
  68         return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
  69 }
  70
  71 static int set_msg_len(u8 *block, unsigned int msglen, int csize)
  72 {
  73         __be32 data;
  74
  75         memset(block, 0, csize);
  76         block += csize;
  77
  78         if (csize >= 4)
  79                 csize = 4;
  80         else if (msglen > (1 << (8 * csize)))
  81                 return -EOVERFLOW;
  82
  83         data = cpu_to_be32(msglen);
  84         memcpy(block - csize, (u8 *)&data + 4 - csize, csize);
  85
  86         return 0;
  87 }
  88
  89 static int crypto_ccm_setkey(struct crypto_aead *aead, const u8 *key,
  90                              unsigned int keylen)
  91 {
  92         struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
  93         struct crypto_skcipher *ctr = ctx->ctr;
  94         struct crypto_ahash *mac = ctx->mac;
  95         int err = 0;
  96
  97         crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
  98         crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
  99                                        CRYPTO_TFM_REQ_MASK);
 100         err = crypto_skcipher_setkey(ctr, key, keylen);
 101         crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctr) &
 102                               CRYPTO_TFM_RES_MASK);
 103         if (err)
 104                 goto out;
 105
 106         crypto_ahash_clear_flags(mac, CRYPTO_TFM_REQ_MASK);
 107         crypto_ahash_set_flags(mac, crypto_aead_get_flags(aead) &
 108                                     CRYPTO_TFM_REQ_MASK);
 109         err = crypto_ahash_setkey(mac, key, keylen);
 110         crypto_aead_set_flags(aead, crypto_ahash_get_flags(mac) &
 111                               CRYPTO_TFM_RES_MASK);
 112
 113 out:
 114         return err;
 115 }
 116
 117 static int crypto_ccm_setauthsize(struct crypto_aead *tfm,
 118                                   unsigned int authsize)
 119 {
 120         switch (authsize) {
 121         case 4:
 122         case 6:
 123         case 8:
 124         case 10:
 125         case 12:
 126         case 14:
 127         case 16:
 128                 break;
 129         default:
 130                 return -EINVAL;
 131         }
 132
 133         return 0;
 134 }
 135
 136 static int format_input(u8 *info, struct aead_request *req,
 137                         unsigned int cryptlen)
 138 {
 139         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 140         unsigned int lp = req->iv[0];
 141         unsigned int l = lp + 1;
 142         unsigned int m;
 143
 144         m = crypto_aead_authsize(aead);
 145
 146         memcpy(info, req->iv, 16);
 147
 148         /* format control info per RFC 3610 and
 149          * NIST Special Publication 800-38C
 150          */
 151         *info |= (8 * ((m - 2) / 2));
 152         if (req->assoclen)
 153                 *info |= 64;
 154
 155         return set_msg_len(info + 16 - l, cryptlen, l);
 156 }
 157
 158 static int format_adata(u8 *adata, unsigned int a)
 159 {
 160         int len = 0;
 161
 162         /* add control info for associated data
 163          * RFC 3610 and NIST Special Publication 800-38C
 164          */
 165         if (a < 65280) {
 166                 *(__be16 *)adata = cpu_to_be16(a);
 167                 len = 2;
 168         } else  {
 169                 *(__be16 *)adata = cpu_to_be16(0xfffe);
 170                 *(__be32 *)&adata[2] = cpu_to_be32(a);
 171                 len = 6;
 172         }
 173
 174         return len;
 175 }
 176
 177 static int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain,
 178                            unsigned int cryptlen)
 179 {
 180         struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
 181         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 182         struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
 183         AHASH_REQUEST_ON_STACK(ahreq, ctx->mac);
 184         unsigned int assoclen = req->assoclen;
 185         struct scatterlist sg[3];
 186         u8 odata[16];
 187         u8 idata[16];
 188         int ilen, err;
 189
 190         /* format control data for input */
 191         err = format_input(odata, req, cryptlen);
 192         if (err)
 193                 goto out;
 194
 195         sg_init_table(sg, 3);
 196         sg_set_buf(&sg[0], odata, 16);
 197
 198         /* format associated data and compute into mac */
 199         if (assoclen) {
 200                 ilen = format_adata(idata, assoclen);
 201                 sg_set_buf(&sg[1], idata, ilen);
 202                 sg_chain(sg, 3, req->src);
 203         } else {
 204                 ilen = 0;
 205                 sg_chain(sg, 2, req->src);
 206         }
 207
 208         ahash_request_set_tfm(ahreq, ctx->mac);
 209         ahash_request_set_callback(ahreq, pctx->flags, NULL, NULL);
 210         ahash_request_set_crypt(ahreq, sg, NULL, assoclen + ilen + 16);
 211         err = crypto_ahash_init(ahreq);
 212         if (err)
 213                 goto out;
 214         err = crypto_ahash_update(ahreq);
 215         if (err)
 216                 goto out;
 217
 218         /* we need to pad the MAC input to a round multiple of the block size */
 219         ilen = 16 - (assoclen + ilen) % 16;
 220         if (ilen < 16) {
 221                 memset(idata, 0, ilen);
 222                 sg_init_table(sg, 2);
 223                 sg_set_buf(&sg[0], idata, ilen);
 224                 if (plain)
 225                         sg_chain(sg, 2, plain);
 226                 plain = sg;
 227                 cryptlen += ilen;
 228         }
 229
 230         ahash_request_set_crypt(ahreq, plain, pctx->odata, cryptlen);
 231         err = crypto_ahash_finup(ahreq);
 232 out:
 233         return err;
 234 }
 235
 236 static void crypto_ccm_encrypt_done(struct crypto_async_request *areq, int err)
 237 {
 238         struct aead_request *req = areq->data;
 239         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 240         struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
 241         u8 *odata = pctx->odata;
 242
 243         if (!err)
 244                 scatterwalk_map_and_copy(odata, req->dst,
 245                                          req->assoclen + req->cryptlen,
 246                                          crypto_aead_authsize(aead), 1);
 247         aead_request_complete(req, err);
 248 }
 249
 250 static inline int crypto_ccm_check_iv(const u8 *iv)
 251 {
 252         /* 2 <= L <= 8, so 1 <= L' <= 7. */
 253         if (1 > iv[0] || iv[0] > 7)
 254                 return -EINVAL;
 255
 256         return 0;
 257 }
 258
 259 static int crypto_ccm_init_crypt(struct aead_request *req, u8 *tag)
 260 {
 261         struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
 262         struct scatterlist *sg;
 263         u8 *iv = req->iv;
 264         int err;
 265
 266         err = crypto_ccm_check_iv(iv);
 267         if (err)
 268                 return err;
 269
 270         pctx->flags = aead_request_flags(req);
 271
 272          /* Note: rfc 3610 and NIST 800-38C require counter of
 273          * zero to encrypt auth tag.
 274          */
 275         memset(iv + 15 - iv[0], 0, iv[0] + 1);
 276
 277         sg_init_table(pctx->src, 3);
 278         sg_set_buf(pctx->src, tag, 16);
 279         sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
 280         if (sg != pctx->src + 1)
 281                 sg_chain(pctx->src, 2, sg);
 282
 283         if (req->src != req->dst) {
 284                 sg_init_table(pctx->dst, 3);
 285                 sg_set_buf(pctx->dst, tag, 16);
 286                 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
 287                 if (sg != pctx->dst + 1)
 288                         sg_chain(pctx->dst, 2, sg);
 289         }
 290
 291         return 0;
 292 }
 293
 294 static int crypto_ccm_encrypt(struct aead_request *req)
 295 {
 296         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 297         struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
 298         struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
 299         struct skcipher_request *skreq = &pctx->skreq;
 300         struct scatterlist *dst;
 301         unsigned int cryptlen = req->cryptlen;
 302         u8 *odata = pctx->odata;
 303         u8 *iv = req->iv;
 304         int err;
 305
 306         err = crypto_ccm_init_crypt(req, odata);
 307         if (err)
 308                 return err;
 309
 310         err = crypto_ccm_auth(req, sg_next(pctx->src), cryptlen);
 311         if (err)
 312                 return err;
 313
 314         dst = pctx->src;
 315         if (req->src != req->dst)
 316                 dst = pctx->dst;
 317
 318         skcipher_request_set_tfm(skreq, ctx->ctr);
 319         skcipher_request_set_callback(skreq, pctx->flags,
 320                                       crypto_ccm_encrypt_done, req);
 321         skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv);
 322         err = crypto_skcipher_encrypt(skreq);
 323         if (err)
 324                 return err;
 325
 326         /* copy authtag to end of dst */
 327         scatterwalk_map_and_copy(odata, sg_next(dst), cryptlen,
 328                                  crypto_aead_authsize(aead), 1);
 329         return err;
 330 }
 331
 332 static void crypto_ccm_decrypt_done(struct crypto_async_request *areq,
 333                                    int err)
 334 {
 335         struct aead_request *req = areq->data;
 336         struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
 337         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 338         unsigned int authsize = crypto_aead_authsize(aead);
 339         unsigned int cryptlen = req->cryptlen - authsize;
 340         struct scatterlist *dst;
 341
 342         pctx->flags = 0;
 343
 344         dst = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
 345
 346         if (!err) {
 347                 err = crypto_ccm_auth(req, dst, cryptlen);
 348                 if (!err && crypto_memneq(pctx->auth_tag, pctx->odata, authsize))
 349                         err = -EBADMSG;
 350         }
 351         aead_request_complete(req, err);
 352 }
 353
 354 static int crypto_ccm_decrypt(struct aead_request *req)
 355 {
 356         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 357         struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
 358         struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
 359         struct skcipher_request *skreq = &pctx->skreq;
 360         struct scatterlist *dst;
 361         unsigned int authsize = crypto_aead_authsize(aead);
 362         unsigned int cryptlen = req->cryptlen;
 363         u8 *authtag = pctx->auth_tag;
 364         u8 *odata = pctx->odata;
 365         u8 *iv = req->iv;
 366         int err;
 367
 368         cryptlen -= authsize;
 369
 370         err = crypto_ccm_init_crypt(req, authtag);
 371         if (err)
 372                 return err;
 373
 374         scatterwalk_map_and_copy(authtag, sg_next(pctx->src), cryptlen,
 375                                  authsize, 0);
 376
 377         dst = pctx->src;
 378         if (req->src != req->dst)
 379                 dst = pctx->dst;
 380
 381         skcipher_request_set_tfm(skreq, ctx->ctr);
 382         skcipher_request_set_callback(skreq, pctx->flags,
 383                                       crypto_ccm_decrypt_done, req);
 384         skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv);
 385         err = crypto_skcipher_decrypt(skreq);
 386         if (err)
 387                 return err;
 388
 389         err = crypto_ccm_auth(req, sg_next(dst), cryptlen);
 390         if (err)
 391                 return err;
 392
 393         /* verify */
 394         if (crypto_memneq(authtag, odata, authsize))
 395                 return -EBADMSG;
 396
 397         return err;
 398 }
 399
 400 static int crypto_ccm_init_tfm(struct crypto_aead *tfm)
 401 {
 402         struct aead_instance *inst = aead_alg_instance(tfm);
 403         struct ccm_instance_ctx *ictx = aead_instance_ctx(inst);
 404         struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm);
 405         struct crypto_ahash *mac;
 406         struct crypto_skcipher *ctr;
 407         unsigned long align;
 408         int err;
 409
 410         mac = crypto_spawn_ahash(&ictx->mac);
 411         if (IS_ERR(mac))
 412                 return PTR_ERR(mac);
 413
 414         ctr = crypto_spawn_skcipher(&ictx->ctr);
 415         err = PTR_ERR(ctr);
 416         if (IS_ERR(ctr))
 417                 goto err_free_mac;
 418
 419         ctx->mac = mac;
 420         ctx->ctr = ctr;
 421
 422         align = crypto_aead_alignmask(tfm);
 423         align &= ~(crypto_tfm_ctx_alignment() - 1);
 424         crypto_aead_set_reqsize(
 425                 tfm,
 426                 align + sizeof(struct crypto_ccm_req_priv_ctx) +
 427                 crypto_skcipher_reqsize(ctr));
 428
 429         return 0;
 430
 431 err_free_mac:
 432         crypto_free_ahash(mac);
 433         return err;
 434 }
 435
 436 static void crypto_ccm_exit_tfm(struct crypto_aead *tfm)
 437 {
 438         struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm);
 439
 440         crypto_free_ahash(ctx->mac);
 441         crypto_free_skcipher(ctx->ctr);
 442 }
 443
 444 static void crypto_ccm_free(struct aead_instance *inst)
 445 {
 446         struct ccm_instance_ctx *ctx = aead_instance_ctx(inst);
 447
 448         crypto_drop_ahash(&ctx->mac);
 449         crypto_drop_skcipher(&ctx->ctr);
 450         kfree(inst);
 451 }
 452
 453 static int crypto_ccm_create_common(struct crypto_template *tmpl,
 454                                     struct rtattr **tb,
 455                                     const char *full_name,
 456                                     const char *ctr_name,
 457                                     const char *mac_name)
 458 {
 459         struct crypto_attr_type *algt;
 460         struct aead_instance *inst;
 461         struct skcipher_alg *ctr;
 462         struct crypto_alg *mac_alg;
 463         struct hash_alg_common *mac;
 464         struct ccm_instance_ctx *ictx;
 465         int err;
 466
 467         algt = crypto_get_attr_type(tb);
 468         if (IS_ERR(algt))
 469                 return PTR_ERR(algt);
 470
 471         if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
 472                 return -EINVAL;
 473
 474         mac_alg = crypto_find_alg(mac_name, &crypto_ahash_type,
 475                                   CRYPTO_ALG_TYPE_HASH,
 476                                   CRYPTO_ALG_TYPE_AHASH_MASK |
 477                                   CRYPTO_ALG_ASYNC);
 478         if (IS_ERR(mac_alg))
 479                 return PTR_ERR(mac_alg);
 480
 481         mac = __crypto_hash_alg_common(mac_alg);
 482         err = -EINVAL;
 483         if (mac->digestsize != 16)
 484                 goto out_put_mac;
 485
 486         inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL);
 487         err = -ENOMEM;
 488         if (!inst)
 489                 goto out_put_mac;
 490
 491         ictx = aead_instance_ctx(inst);
 492         err = crypto_init_ahash_spawn(&ictx->mac, mac,
 493                                       aead_crypto_instance(inst));
 494         if (err)
 495                 goto err_free_inst;
 496
 497         crypto_set_skcipher_spawn(&ictx->ctr, aead_crypto_instance(inst));
 498         err = crypto_grab_skcipher(&ictx->ctr, ctr_name, 0,
 499                                    crypto_requires_sync(algt->type,
 500                                                         algt->mask));
 501         if (err)
 502                 goto err_drop_mac;
 503
 504         ctr = crypto_spawn_skcipher_alg(&ictx->ctr);
 505
 506         /* Not a stream cipher? */
 507         err = -EINVAL;
 508         if (ctr->base.cra_blocksize != 1)
 509                 goto err_drop_ctr;
 510
 511         /* We want the real thing! */
 512         if (crypto_skcipher_alg_ivsize(ctr) != 16)
 513                 goto err_drop_ctr;
 514
 515         err = -ENAMETOOLONG;
 516         if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
 517                      "ccm_base(%s,%s)", ctr->base.cra_driver_name,
 518                      mac->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 519                 goto err_drop_ctr;
 520
 521         memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
 522
 523         inst->alg.base.cra_flags = ctr->base.cra_flags & CRYPTO_ALG_ASYNC;
 524         inst->alg.base.cra_priority = (mac->base.cra_priority +
 525                                        ctr->base.cra_priority) / 2;
 526         inst->alg.base.cra_blocksize = 1;
 527         inst->alg.base.cra_alignmask = mac->base.cra_alignmask |
 528                                        ctr->base.cra_alignmask |
 529                                        (__alignof__(u32) - 1);
 530         inst->alg.ivsize = 16;
 531         inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
 532         inst->alg.maxauthsize = 16;
 533         inst->alg.base.cra_ctxsize = sizeof(struct crypto_ccm_ctx);
 534         inst->alg.init = crypto_ccm_init_tfm;
 535         inst->alg.exit = crypto_ccm_exit_tfm;
 536         inst->alg.setkey = crypto_ccm_setkey;
 537         inst->alg.setauthsize = crypto_ccm_setauthsize;
 538         inst->alg.encrypt = crypto_ccm_encrypt;
 539         inst->alg.decrypt = crypto_ccm_decrypt;
 540
 541         inst->free = crypto_ccm_free;
 542
 543         err = aead_register_instance(tmpl, inst);
 544         if (err)
 545                 goto err_drop_ctr;
 546
 547 out_put_mac:
 548         crypto_mod_put(mac_alg);
 549         return err;
 550
 551 err_drop_ctr:
 552         crypto_drop_skcipher(&ictx->ctr);
 553 err_drop_mac:
 554         crypto_drop_ahash(&ictx->mac);
 555 err_free_inst:
 556         kfree(inst);
 557         goto out_put_mac;
 558 }
 559
 560 static int crypto_ccm_create(struct crypto_template *tmpl, struct rtattr **tb)
 561 {
 562         const char *cipher_name;
 563         char ctr_name[CRYPTO_MAX_ALG_NAME];
 564         char mac_name[CRYPTO_MAX_ALG_NAME];
 565         char full_name[CRYPTO_MAX_ALG_NAME];
 566
 567         cipher_name = crypto_attr_alg_name(tb[1]);
 568         if (IS_ERR(cipher_name))
 569                 return PTR_ERR(cipher_name);
 570
 571         if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)",
 572                      cipher_name) >= CRYPTO_MAX_ALG_NAME)
 573                 return -ENAMETOOLONG;
 574
 575         if (snprintf(mac_name, CRYPTO_MAX_ALG_NAME, "cbcmac(%s)",
 576                      cipher_name) >= CRYPTO_MAX_ALG_NAME)
 577                 return -ENAMETOOLONG;
 578
 579         if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm(%s)", cipher_name) >=
 580             CRYPTO_MAX_ALG_NAME)
 581                 return -ENAMETOOLONG;
 582
 583         return crypto_ccm_create_common(tmpl, tb, full_name, ctr_name,
 584                                         mac_name);
 585 }
 586
 587 static struct crypto_template crypto_ccm_tmpl = {
 588         .name = "ccm",
 589         .create = crypto_ccm_create,
 590         .module = THIS_MODULE,
 591 };
 592
 593 static int crypto_ccm_base_create(struct crypto_template *tmpl,
 594                                   struct rtattr **tb)
 595 {
 596         const char *ctr_name;
 597         const char *cipher_name;
 598         char full_name[CRYPTO_MAX_ALG_NAME];
 599
 600         ctr_name = crypto_attr_alg_name(tb[1]);
 601         if (IS_ERR(ctr_name))
 602                 return PTR_ERR(ctr_name);
 603
 604         cipher_name = crypto_attr_alg_name(tb[2]);
 605         if (IS_ERR(cipher_name))
 606                 return PTR_ERR(cipher_name);
 607
 608         if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm_base(%s,%s)",
 609                      ctr_name, cipher_name) >= CRYPTO_MAX_ALG_NAME)
 610                 return -ENAMETOOLONG;
 611
 612         return crypto_ccm_create_common(tmpl, tb, full_name, ctr_name,
 613                                         cipher_name);
 614 }
 615
 616 static struct crypto_template crypto_ccm_base_tmpl = {
 617         .name = "ccm_base",
 618         .create = crypto_ccm_base_create,
 619         .module = THIS_MODULE,
 620 };
 621
 622 static int crypto_rfc4309_setkey(struct crypto_aead *parent, const u8 *key,
 623                                  unsigned int keylen)
 624 {
 625         struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent);
 626         struct crypto_aead *child = ctx->child;
 627         int err;
 628
 629         if (keylen < 3)
 630                 return -EINVAL;
 631
 632         keylen -= 3;
 633         memcpy(ctx->nonce, key + keylen, 3);
 634
 635         crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
 636         crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
 637                                      CRYPTO_TFM_REQ_MASK);
 638         err = crypto_aead_setkey(child, key, keylen);
 639         crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
 640                                       CRYPTO_TFM_RES_MASK);
 641
 642         return err;
 643 }
 644
 645 static int crypto_rfc4309_setauthsize(struct crypto_aead *parent,
 646                                       unsigned int authsize)
 647 {
 648         struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent);
 649
 650         switch (authsize) {
 651         case 8:
 652         case 12:
 653         case 16:
 654                 break;
 655         default:
 656                 return -EINVAL;
 657         }
 658
 659         return crypto_aead_setauthsize(ctx->child, authsize);
 660 }
 661
 662 static struct aead_request *crypto_rfc4309_crypt(struct aead_request *req)
 663 {
 664         struct crypto_rfc4309_req_ctx *rctx = aead_request_ctx(req);
 665         struct aead_request *subreq = &rctx->subreq;
 666         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 667         struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(aead);
 668         struct crypto_aead *child = ctx->child;
 669         struct scatterlist *sg;
 670         u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
 671                            crypto_aead_alignmask(child) + 1);
 672
 673         /* L' */
 674         iv[0] = 3;
 675
 676         memcpy(iv + 1, ctx->nonce, 3);
 677         memcpy(iv + 4, req->iv, 8);
 678
 679         scatterwalk_map_and_copy(iv + 16, req->src, 0, req->assoclen - 8, 0);
 680
 681         sg_init_table(rctx->src, 3);
 682         sg_set_buf(rctx->src, iv + 16, req->assoclen - 8);
 683         sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
 684         if (sg != rctx->src + 1)
 685                 sg_chain(rctx->src, 2, sg);
 686
 687         if (req->src != req->dst) {
 688                 sg_init_table(rctx->dst, 3);
 689                 sg_set_buf(rctx->dst, iv + 16, req->assoclen - 8);
 690                 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
 691                 if (sg != rctx->dst + 1)
 692                         sg_chain(rctx->dst, 2, sg);
 693         }
 694
 695         aead_request_set_tfm(subreq, child);
 696         aead_request_set_callback(subreq, req->base.flags, req->base.complete,
 697                                   req->base.data);
 698         aead_request_set_crypt(subreq, rctx->src,
 699                                req->src == req->dst ? rctx->src : rctx->dst,
 700                                req->cryptlen, iv);
 701         aead_request_set_ad(subreq, req->assoclen - 8);
 702
 703         return subreq;
 704 }
 705
 706 static int crypto_rfc4309_encrypt(struct aead_request *req)
 707 {
 708         if (req->assoclen != 16 && req->assoclen != 20)
 709                 return -EINVAL;
 710
 711         req = crypto_rfc4309_crypt(req);
 712
 713         return crypto_aead_encrypt(req);
 714 }
 715
 716 static int crypto_rfc4309_decrypt(struct aead_request *req)
 717 {
 718         if (req->assoclen != 16 && req->assoclen != 20)
 719                 return -EINVAL;
 720
 721         req = crypto_rfc4309_crypt(req);
 722
 723         return crypto_aead_decrypt(req);
 724 }
 725
 726 static int crypto_rfc4309_init_tfm(struct crypto_aead *tfm)
 727 {
 728         struct aead_instance *inst = aead_alg_instance(tfm);
 729         struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
 730         struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm);
 731         struct crypto_aead *aead;
 732         unsigned long align;
 733
 734         aead = crypto_spawn_aead(spawn);
 735         if (IS_ERR(aead))
 736                 return PTR_ERR(aead);
 737
 738         ctx->child = aead;
 739
 740         align = crypto_aead_alignmask(aead);
 741         align &= ~(crypto_tfm_ctx_alignment() - 1);
 742         crypto_aead_set_reqsize(
 743                 tfm,
 744                 sizeof(struct crypto_rfc4309_req_ctx) +
 745                 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
 746                 align + 32);
 747
 748         return 0;
 749 }
 750
 751 static void crypto_rfc4309_exit_tfm(struct crypto_aead *tfm)
 752 {
 753         struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm);
 754
 755         crypto_free_aead(ctx->child);
 756 }
 757
 758 static void crypto_rfc4309_free(struct aead_instance *inst)
 759 {
 760         crypto_drop_aead(aead_instance_ctx(inst));
 761         kfree(inst);
 762 }
 763
 764 static int crypto_rfc4309_create(struct crypto_template *tmpl,
 765                                  struct rtattr **tb)
 766 {
 767         struct crypto_attr_type *algt;
 768         struct aead_instance *inst;
 769         struct crypto_aead_spawn *spawn;
 770         struct aead_alg *alg;
 771         const char *ccm_name;
 772         int err;
 773
 774         algt = crypto_get_attr_type(tb);
 775         if (IS_ERR(algt))
 776                 return PTR_ERR(algt);
 777
 778         if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
 779                 return -EINVAL;
 780
 781         ccm_name = crypto_attr_alg_name(tb[1]);
 782         if (IS_ERR(ccm_name))
 783                 return PTR_ERR(ccm_name);
 784
 785         inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
 786         if (!inst)
 787                 return -ENOMEM;
 788
 789         spawn = aead_instance_ctx(inst);
 790         crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
 791         err = crypto_grab_aead(spawn, ccm_name, 0,
 792                                crypto_requires_sync(algt->type, algt->mask));
 793         if (err)
 794                 goto out_free_inst;
 795
 796         alg = crypto_spawn_aead_alg(spawn);
 797
 798         err = -EINVAL;
 799
 800         /* We only support 16-byte blocks. */
 801         if (crypto_aead_alg_ivsize(alg) != 16)
 802                 goto out_drop_alg;
 803
 804         /* Not a stream cipher? */
 805         if (alg->base.cra_blocksize != 1)
 806                 goto out_drop_alg;
 807
 808         err = -ENAMETOOLONG;
 809         if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
 810                      "rfc4309(%s)", alg->base.cra_name) >=
 811             CRYPTO_MAX_ALG_NAME ||
 812             snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
 813                      "rfc4309(%s)", alg->base.cra_driver_name) >=
 814             CRYPTO_MAX_ALG_NAME)
 815                 goto out_drop_alg;
 816
 817         inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
 818         inst->alg.base.cra_priority = alg->base.cra_priority;
 819         inst->alg.base.cra_blocksize = 1;
 820         inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
 821
 822         inst->alg.ivsize = 8;
 823         inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
 824         inst->alg.maxauthsize = 16;
 825
 826         inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4309_ctx);
 827
 828         inst->alg.init = crypto_rfc4309_init_tfm;
 829         inst->alg.exit = crypto_rfc4309_exit_tfm;
 830
 831         inst->alg.setkey = crypto_rfc4309_setkey;
 832         inst->alg.setauthsize = crypto_rfc4309_setauthsize;
 833         inst->alg.encrypt = crypto_rfc4309_encrypt;
 834         inst->alg.decrypt = crypto_rfc4309_decrypt;
 835
 836         inst->free = crypto_rfc4309_free;
 837
 838         err = aead_register_instance(tmpl, inst);
 839         if (err)
 840                 goto out_drop_alg;
 841
 842 out:
 843         return err;
 844
 845 out_drop_alg:
 846         crypto_drop_aead(spawn);
 847 out_free_inst:
 848         kfree(inst);
 849         goto out;
 850 }
 851
 852 static struct crypto_template crypto_rfc4309_tmpl = {
 853         .name = "rfc4309",
 854         .create = crypto_rfc4309_create,
 855         .module = THIS_MODULE,
 856 };
 857
 858 static int crypto_cbcmac_digest_setkey(struct crypto_shash *parent,
 859                                      const u8 *inkey, unsigned int keylen)
 860 {
 861         struct cbcmac_tfm_ctx *ctx = crypto_shash_ctx(parent);
 862
 863         return crypto_cipher_setkey(ctx->child, inkey, keylen);
 864 }
 865
 866 static int crypto_cbcmac_digest_init(struct shash_desc *pdesc)
 867 {
 868         struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
 869         int bs = crypto_shash_digestsize(pdesc->tfm);
 870         u8 *dg = (u8 *)ctx + crypto_shash_descsize(pdesc->tfm) - bs;
 871
 872         ctx->len = 0;
 873         memset(dg, 0, bs);
 874
 875         return 0;
 876 }
 877
 878 static int crypto_cbcmac_digest_update(struct shash_desc *pdesc, const u8 *p,
 879                                        unsigned int len)
 880 {
 881         struct crypto_shash *parent = pdesc->tfm;
 882         struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
 883         struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
 884         struct crypto_cipher *tfm = tctx->child;
 885         int bs = crypto_shash_digestsize(parent);
 886         u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs;
 887
 888         while (len > 0) {
 889                 unsigned int l = min(len, bs - ctx->len);
 890
 891                 crypto_xor(dg + ctx->len, p, l);
 892                 ctx->len +=l;
 893                 len -= l;
 894                 p += l;
 895
 896                 if (ctx->len == bs) {
 897                         crypto_cipher_encrypt_one(tfm, dg, dg);
 898                         ctx->len = 0;
 899                 }
 900         }
 901
 902         return 0;
 903 }
 904
 905 static int crypto_cbcmac_digest_final(struct shash_desc *pdesc, u8 *out)
 906 {
 907         struct crypto_shash *parent = pdesc->tfm;
 908         struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
 909         struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
 910         struct crypto_cipher *tfm = tctx->child;
 911         int bs = crypto_shash_digestsize(parent);
 912         u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs;
 913
 914         if (ctx->len)
 915                 crypto_cipher_encrypt_one(tfm, dg, dg);
 916
 917         memcpy(out, dg, bs);
 918         return 0;
 919 }
 920
 921 static int cbcmac_init_tfm(struct crypto_tfm *tfm)
 922 {
 923         struct crypto_cipher *cipher;
 924         struct crypto_instance *inst = (void *)tfm->__crt_alg;
 925         struct crypto_spawn *spawn = crypto_instance_ctx(inst);
 926         struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
 927
 928         cipher = crypto_spawn_cipher(spawn);
 929         if (IS_ERR(cipher))
 930                 return PTR_ERR(cipher);
 931
 932         ctx->child = cipher;
 933
 934         return 0;
 935 };
 936
 937 static void cbcmac_exit_tfm(struct crypto_tfm *tfm)
 938 {
 939         struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
 940         crypto_free_cipher(ctx->child);
 941 }
 942
 943 static int cbcmac_create(struct crypto_template *tmpl, struct rtattr **tb)
 944 {
 945         struct shash_instance *inst;
 946         struct crypto_alg *alg;
 947         int err;
 948
 949         err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH);
 950         if (err)
 951                 return err;
 952
 953         alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
 954                                   CRYPTO_ALG_TYPE_MASK);
 955         if (IS_ERR(alg))
 956                 return PTR_ERR(alg);
 957
 958         inst = shash_alloc_instance("cbcmac", alg);
 959         err = PTR_ERR(inst);
 960         if (IS_ERR(inst))
 961                 goto out_put_alg;
 962
 963         err = crypto_init_spawn(shash_instance_ctx(inst), alg,
 964                                 shash_crypto_instance(inst),
 965                                 CRYPTO_ALG_TYPE_MASK);
 966         if (err)
 967                 goto out_free_inst;
 968
 969         inst->alg.base.cra_priority = alg->cra_priority;
 970         inst->alg.base.cra_blocksize = 1;
 971
 972         inst->alg.digestsize = alg->cra_blocksize;
 973         inst->alg.descsize = ALIGN(sizeof(struct cbcmac_desc_ctx),
 974                                    alg->cra_alignmask + 1) +
 975                              alg->cra_blocksize;
 976
 977         inst->alg.base.cra_ctxsize = sizeof(struct cbcmac_tfm_ctx);
 978         inst->alg.base.cra_init = cbcmac_init_tfm;
 979         inst->alg.base.cra_exit = cbcmac_exit_tfm;
 980
 981         inst->alg.init = crypto_cbcmac_digest_init;
 982         inst->alg.update = crypto_cbcmac_digest_update;
 983         inst->alg.final = crypto_cbcmac_digest_final;
 984         inst->alg.setkey = crypto_cbcmac_digest_setkey;
 985
 986         err = shash_register_instance(tmpl, inst);
 987
 988 out_free_inst:
 989         if (err)
 990                 shash_free_instance(shash_crypto_instance(inst));
 991
 992 out_put_alg:
 993         crypto_mod_put(alg);
 994         return err;
 995 }
 996
 997 static struct crypto_template crypto_cbcmac_tmpl = {
 998         .name = "cbcmac",
 999         .create = cbcmac_create,
1000         .free = shash_free_instance,
1001         .module = THIS_MODULE,
1002 };
1003
1004 static int __init crypto_ccm_module_init(void)
1005 {
1006         int err;
1007
1008         err = crypto_register_template(&crypto_cbcmac_tmpl);
1009         if (err)
1010                 goto out;
1011
1012         err = crypto_register_template(&crypto_ccm_base_tmpl);
1013         if (err)
1014                 goto out_undo_cbcmac;
1015
1016         err = crypto_register_template(&crypto_ccm_tmpl);
1017         if (err)
1018                 goto out_undo_base;
1019
1020         err = crypto_register_template(&crypto_rfc4309_tmpl);
1021         if (err)
1022                 goto out_undo_ccm;
1023
1024 out:
1025         return err;
1026
1027 out_undo_ccm:
1028         crypto_unregister_template(&crypto_ccm_tmpl);
1029 out_undo_base:
1030         crypto_unregister_template(&crypto_ccm_base_tmpl);
1031 out_undo_cbcmac:
1032         crypto_register_template(&crypto_cbcmac_tmpl);
1033         goto out;
1034 }
1035
1036 static void __exit crypto_ccm_module_exit(void)
1037 {
1038         crypto_unregister_template(&crypto_rfc4309_tmpl);
1039         crypto_unregister_template(&crypto_ccm_tmpl);
1040         crypto_unregister_template(&crypto_ccm_base_tmpl);
1041         crypto_unregister_template(&crypto_cbcmac_tmpl);
1042 }
1043
1044 module_init(crypto_ccm_module_init);
1045 module_exit(crypto_ccm_module_exit);
1046
1047 MODULE_LICENSE("GPL");
1048 MODULE_DESCRIPTION("Counter with CBC MAC");
1049 MODULE_ALIAS_CRYPTO("ccm_base");
1050 MODULE_ALIAS_CRYPTO("rfc4309");
1051 MODULE_ALIAS_CRYPTO("ccm");