crypto/gcm.c

   1 /*
   2  * GCM: Galois/Counter Mode.
   3  *
   4  * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi>
   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 version 2 as published
   8  * by the Free Software Foundation.
   9  */
  10
  11 #include <crypto/gf128mul.h>
  12 #include <crypto/internal/aead.h>
  13 #include <crypto/internal/skcipher.h>
  14 #include <crypto/internal/hash.h>
  15 #include <crypto/scatterwalk.h>
  16 #include <crypto/hash.h>
  17 #include "internal.h"
  18 #include <linux/completion.h>
  19 #include <linux/err.h>
  20 #include <linux/init.h>
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23 #include <linux/slab.h>
  24
  25 struct gcm_instance_ctx {
  26         struct crypto_skcipher_spawn ctr;
  27         struct crypto_ahash_spawn ghash;
  28 };
  29
  30 struct crypto_gcm_ctx {
  31         struct crypto_ablkcipher *ctr;
  32         struct crypto_ahash *ghash;
  33 };
  34
  35 struct crypto_rfc4106_ctx {
  36         struct crypto_aead *child;
  37         u8 nonce[4];
  38 };
  39
  40 struct crypto_rfc4543_instance_ctx {
  41         struct crypto_aead_spawn aead;
  42         struct crypto_skcipher_spawn null;
  43 };
  44
  45 struct crypto_rfc4543_ctx {
  46         struct crypto_aead *child;
  47         struct crypto_blkcipher *null;
  48         u8 nonce[4];
  49 };
  50
  51 struct crypto_rfc4543_req_ctx {
  52         u8 auth_tag[16];
  53         u8 assocbuf[32];
  54         struct scatterlist cipher[1];
  55         struct scatterlist payload[2];
  56         struct scatterlist assoc[2];
  57         struct aead_request subreq;
  58 };
  59
  60 struct crypto_gcm_ghash_ctx {
  61         unsigned int cryptlen;
  62         struct scatterlist *src;
  63         void (*complete)(struct aead_request *req, int err);
  64 };
  65
  66 struct crypto_gcm_req_priv_ctx {
  67         u8 auth_tag[16];
  68         u8 iauth_tag[16];
  69         struct scatterlist src[2];
  70         struct scatterlist dst[2];
  71         struct crypto_gcm_ghash_ctx ghash_ctx;
  72         union {
  73                 struct ahash_request ahreq;
  74                 struct ablkcipher_request abreq;
  75         } u;
  76 };
  77
  78 struct crypto_gcm_setkey_result {
  79         int err;
  80         struct completion completion;
  81 };
  82
  83 static void *gcm_zeroes;
  84
  85 static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
  86         struct aead_request *req)
  87 {
  88         unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
  89
  90         return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
  91 }
  92
  93 static void crypto_gcm_setkey_done(struct crypto_async_request *req, int err)
  94 {
  95         struct crypto_gcm_setkey_result *result = req->data;
  96
  97         if (err == -EINPROGRESS)
  98                 return;
  99
 100         result->err = err;
 101         complete(&result->completion);
 102 }
 103
 104 static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
 105                              unsigned int keylen)
 106 {
 107         struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
 108         struct crypto_ahash *ghash = ctx->ghash;
 109         struct crypto_ablkcipher *ctr = ctx->ctr;
 110         struct {
 111                 be128 hash;
 112                 u8 iv[8];
 113
 114                 struct crypto_gcm_setkey_result result;
 115
 116                 struct scatterlist sg[1];
 117                 struct ablkcipher_request req;
 118         } *data;
 119         int err;
 120
 121         crypto_ablkcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
 122         crypto_ablkcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
 123                                    CRYPTO_TFM_REQ_MASK);
 124
 125         err = crypto_ablkcipher_setkey(ctr, key, keylen);
 126         if (err)
 127                 return err;
 128
 129         crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctr) &
 130                                        CRYPTO_TFM_RES_MASK);
 131
 132         data = kzalloc(sizeof(*data) + crypto_ablkcipher_reqsize(ctr),
 133                        GFP_KERNEL);
 134         if (!data)
 135                 return -ENOMEM;
 136
 137         init_completion(&data->result.completion);
 138         sg_init_one(data->sg, &data->hash, sizeof(data->hash));
 139         ablkcipher_request_set_tfm(&data->req, ctr);
 140         ablkcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
 141                                                     CRYPTO_TFM_REQ_MAY_BACKLOG,
 142                                         crypto_gcm_setkey_done,
 143                                         &data->result);
 144         ablkcipher_request_set_crypt(&data->req, data->sg, data->sg,
 145                                      sizeof(data->hash), data->iv);
 146
 147         err = crypto_ablkcipher_encrypt(&data->req);
 148         if (err == -EINPROGRESS || err == -EBUSY) {
 149                 err = wait_for_completion_interruptible(
 150                         &data->result.completion);
 151                 if (!err)
 152                         err = data->result.err;
 153         }
 154
 155         if (err)
 156                 goto out;
 157
 158         crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK);
 159         crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) &
 160                                CRYPTO_TFM_REQ_MASK);
 161         err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128));
 162         crypto_aead_set_flags(aead, crypto_ahash_get_flags(ghash) &
 163                               CRYPTO_TFM_RES_MASK);
 164
 165 out:
 166         kfree(data);
 167         return err;
 168 }
 169
 170 static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
 171                                   unsigned int authsize)
 172 {
 173         switch (authsize) {
 174         case 4:
 175         case 8:
 176         case 12:
 177         case 13:
 178         case 14:
 179         case 15:
 180         case 16:
 181                 break;
 182         default:
 183                 return -EINVAL;
 184         }
 185
 186         return 0;
 187 }
 188
 189 static void crypto_gcm_init_crypt(struct ablkcipher_request *ablk_req,
 190                                   struct aead_request *req,
 191                                   unsigned int cryptlen)
 192 {
 193         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 194         struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
 195         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 196         struct scatterlist *dst;
 197         __be32 counter = cpu_to_be32(1);
 198
 199         memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
 200         memcpy(req->iv + 12, &counter, 4);
 201
 202         sg_init_table(pctx->src, 2);
 203         sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
 204         scatterwalk_sg_chain(pctx->src, 2, req->src);
 205
 206         dst = pctx->src;
 207         if (req->src != req->dst) {
 208                 sg_init_table(pctx->dst, 2);
 209                 sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag));
 210                 scatterwalk_sg_chain(pctx->dst, 2, req->dst);
 211                 dst = pctx->dst;
 212         }
 213
 214         ablkcipher_request_set_tfm(ablk_req, ctx->ctr);
 215         ablkcipher_request_set_crypt(ablk_req, pctx->src, dst,
 216                                      cryptlen + sizeof(pctx->auth_tag),
 217                                      req->iv);
 218 }
 219
 220 static inline unsigned int gcm_remain(unsigned int len)
 221 {
 222         len &= 0xfU;
 223         return len ? 16 - len : 0;
 224 }
 225
 226 static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
 227 static void gcm_hash_final_done(struct crypto_async_request *areq, int err);
 228
 229 static int gcm_hash_update(struct aead_request *req,
 230                            struct crypto_gcm_req_priv_ctx *pctx,
 231                            crypto_completion_t complete,
 232                            struct scatterlist *src,
 233                            unsigned int len)
 234 {
 235         struct ahash_request *ahreq = &pctx->u.ahreq;
 236
 237         ahash_request_set_callback(ahreq, aead_request_flags(req),
 238                                    complete, req);
 239         ahash_request_set_crypt(ahreq, src, NULL, len);
 240
 241         return crypto_ahash_update(ahreq);
 242 }
 243
 244 static int gcm_hash_remain(struct aead_request *req,
 245                            struct crypto_gcm_req_priv_ctx *pctx,
 246                            unsigned int remain,
 247                            crypto_completion_t complete)
 248 {
 249         struct ahash_request *ahreq = &pctx->u.ahreq;
 250
 251         ahash_request_set_callback(ahreq, aead_request_flags(req),
 252                                    complete, req);
 253         sg_init_one(pctx->src, gcm_zeroes, remain);
 254         ahash_request_set_crypt(ahreq, pctx->src, NULL, remain);
 255
 256         return crypto_ahash_update(ahreq);
 257 }
 258
 259 static int gcm_hash_len(struct aead_request *req,
 260                         struct crypto_gcm_req_priv_ctx *pctx)
 261 {
 262         struct ahash_request *ahreq = &pctx->u.ahreq;
 263         struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
 264         u128 lengths;
 265
 266         lengths.a = cpu_to_be64(req->assoclen * 8);
 267         lengths.b = cpu_to_be64(gctx->cryptlen * 8);
 268         memcpy(pctx->iauth_tag, &lengths, 16);
 269         sg_init_one(pctx->src, pctx->iauth_tag, 16);
 270         ahash_request_set_callback(ahreq, aead_request_flags(req),
 271                                    gcm_hash_len_done, req);
 272         ahash_request_set_crypt(ahreq, pctx->src,
 273                                 NULL, sizeof(lengths));
 274
 275         return crypto_ahash_update(ahreq);
 276 }
 277
 278 static int gcm_hash_final(struct aead_request *req,
 279                           struct crypto_gcm_req_priv_ctx *pctx)
 280 {
 281         struct ahash_request *ahreq = &pctx->u.ahreq;
 282
 283         ahash_request_set_callback(ahreq, aead_request_flags(req),
 284                                    gcm_hash_final_done, req);
 285         ahash_request_set_crypt(ahreq, NULL, pctx->iauth_tag, 0);
 286
 287         return crypto_ahash_final(ahreq);
 288 }
 289
 290 static void __gcm_hash_final_done(struct aead_request *req, int err)
 291 {
 292         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 293         struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
 294
 295         if (!err)
 296                 crypto_xor(pctx->auth_tag, pctx->iauth_tag, 16);
 297
 298         gctx->complete(req, err);
 299 }
 300
 301 static void gcm_hash_final_done(struct crypto_async_request *areq, int err)
 302 {
 303         struct aead_request *req = areq->data;
 304
 305         __gcm_hash_final_done(req, err);
 306 }
 307
 308 static void __gcm_hash_len_done(struct aead_request *req, int err)
 309 {
 310         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 311
 312         if (!err) {
 313                 err = gcm_hash_final(req, pctx);
 314                 if (err == -EINPROGRESS || err == -EBUSY)
 315                         return;
 316         }
 317
 318         __gcm_hash_final_done(req, err);
 319 }
 320
 321 static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
 322 {
 323         struct aead_request *req = areq->data;
 324
 325         __gcm_hash_len_done(req, err);
 326 }
 327
 328 static void __gcm_hash_crypt_remain_done(struct aead_request *req, int err)
 329 {
 330         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 331
 332         if (!err) {
 333                 err = gcm_hash_len(req, pctx);
 334                 if (err == -EINPROGRESS || err == -EBUSY)
 335                         return;
 336         }
 337
 338         __gcm_hash_len_done(req, err);
 339 }
 340
 341 static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
 342                                        int err)
 343 {
 344         struct aead_request *req = areq->data;
 345
 346         __gcm_hash_crypt_remain_done(req, err);
 347 }
 348
 349 static void __gcm_hash_crypt_done(struct aead_request *req, int err)
 350 {
 351         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 352         struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
 353         unsigned int remain;
 354
 355         if (!err) {
 356                 remain = gcm_remain(gctx->cryptlen);
 357                 BUG_ON(!remain);
 358                 err = gcm_hash_remain(req, pctx, remain,
 359                                       gcm_hash_crypt_remain_done);
 360                 if (err == -EINPROGRESS || err == -EBUSY)
 361                         return;
 362         }
 363
 364         __gcm_hash_crypt_remain_done(req, err);
 365 }
 366
 367 static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
 368 {
 369         struct aead_request *req = areq->data;
 370
 371         __gcm_hash_crypt_done(req, err);
 372 }
 373
 374 static void __gcm_hash_assoc_remain_done(struct aead_request *req, int err)
 375 {
 376         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 377         struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
 378         crypto_completion_t complete;
 379         unsigned int remain = 0;
 380
 381         if (!err && gctx->cryptlen) {
 382                 remain = gcm_remain(gctx->cryptlen);
 383                 complete = remain ? gcm_hash_crypt_done :
 384                         gcm_hash_crypt_remain_done;
 385                 err = gcm_hash_update(req, pctx, complete,
 386                                       gctx->src, gctx->cryptlen);
 387                 if (err == -EINPROGRESS || err == -EBUSY)
 388                         return;
 389         }
 390
 391         if (remain)
 392                 __gcm_hash_crypt_done(req, err);
 393         else
 394                 __gcm_hash_crypt_remain_done(req, err);
 395 }
 396
 397 static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
 398                                        int err)
 399 {
 400         struct aead_request *req = areq->data;
 401
 402         __gcm_hash_assoc_remain_done(req, err);
 403 }
 404
 405 static void __gcm_hash_assoc_done(struct aead_request *req, int err)
 406 {
 407         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 408         unsigned int remain;
 409
 410         if (!err) {
 411                 remain = gcm_remain(req->assoclen);
 412                 BUG_ON(!remain);
 413                 err = gcm_hash_remain(req, pctx, remain,
 414                                       gcm_hash_assoc_remain_done);
 415                 if (err == -EINPROGRESS || err == -EBUSY)
 416                         return;
 417         }
 418
 419         __gcm_hash_assoc_remain_done(req, err);
 420 }
 421
 422 static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
 423 {
 424         struct aead_request *req = areq->data;
 425
 426         __gcm_hash_assoc_done(req, err);
 427 }
 428
 429 static void __gcm_hash_init_done(struct aead_request *req, int err)
 430 {
 431         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 432         crypto_completion_t complete;
 433         unsigned int remain = 0;
 434
 435         if (!err && req->assoclen) {
 436                 remain = gcm_remain(req->assoclen);
 437                 complete = remain ? gcm_hash_assoc_done :
 438                         gcm_hash_assoc_remain_done;
 439                 err = gcm_hash_update(req, pctx, complete,
 440                                       req->assoc, req->assoclen);
 441                 if (err == -EINPROGRESS || err == -EBUSY)
 442                         return;
 443         }
 444
 445         if (remain)
 446                 __gcm_hash_assoc_done(req, err);
 447         else
 448                 __gcm_hash_assoc_remain_done(req, err);
 449 }
 450
 451 static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
 452 {
 453         struct aead_request *req = areq->data;
 454
 455         __gcm_hash_init_done(req, err);
 456 }
 457
 458 static int gcm_hash(struct aead_request *req,
 459                     struct crypto_gcm_req_priv_ctx *pctx)
 460 {
 461         struct ahash_request *ahreq = &pctx->u.ahreq;
 462         struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
 463         struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
 464         unsigned int remain;
 465         crypto_completion_t complete;
 466         int err;
 467
 468         ahash_request_set_tfm(ahreq, ctx->ghash);
 469
 470         ahash_request_set_callback(ahreq, aead_request_flags(req),
 471                                    gcm_hash_init_done, req);
 472         err = crypto_ahash_init(ahreq);
 473         if (err)
 474                 return err;
 475         remain = gcm_remain(req->assoclen);
 476         complete = remain ? gcm_hash_assoc_done : gcm_hash_assoc_remain_done;
 477         err = gcm_hash_update(req, pctx, complete, req->assoc, req->assoclen);
 478         if (err)
 479                 return err;
 480         if (remain) {
 481                 err = gcm_hash_remain(req, pctx, remain,
 482                                       gcm_hash_assoc_remain_done);
 483                 if (err)
 484                         return err;
 485         }
 486         remain = gcm_remain(gctx->cryptlen);
 487         complete = remain ? gcm_hash_crypt_done : gcm_hash_crypt_remain_done;
 488         err = gcm_hash_update(req, pctx, complete, gctx->src, gctx->cryptlen);
 489         if (err)
 490                 return err;
 491         if (remain) {
 492                 err = gcm_hash_remain(req, pctx, remain,
 493                                       gcm_hash_crypt_remain_done);
 494                 if (err)
 495                         return err;
 496         }
 497         err = gcm_hash_len(req, pctx);
 498         if (err)
 499                 return err;
 500         err = gcm_hash_final(req, pctx);
 501         if (err)
 502                 return err;
 503
 504         return 0;
 505 }
 506
 507 static void gcm_enc_copy_hash(struct aead_request *req,
 508                               struct crypto_gcm_req_priv_ctx *pctx)
 509 {
 510         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 511         u8 *auth_tag = pctx->auth_tag;
 512
 513         scatterwalk_map_and_copy(auth_tag, req->dst, req->cryptlen,
 514                                  crypto_aead_authsize(aead), 1);
 515 }
 516
 517 static void gcm_enc_hash_done(struct aead_request *req, int err)
 518 {
 519         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 520
 521         if (!err)
 522                 gcm_enc_copy_hash(req, pctx);
 523
 524         aead_request_complete(req, err);
 525 }
 526
 527 static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
 528 {
 529         struct aead_request *req = areq->data;
 530         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 531
 532         if (!err) {
 533                 err = gcm_hash(req, pctx);
 534                 if (err == -EINPROGRESS || err == -EBUSY)
 535                         return;
 536                 else if (!err) {
 537                         crypto_xor(pctx->auth_tag, pctx->iauth_tag, 16);
 538                         gcm_enc_copy_hash(req, pctx);
 539                 }
 540         }
 541
 542         aead_request_complete(req, err);
 543 }
 544
 545 static int crypto_gcm_encrypt(struct aead_request *req)
 546 {
 547         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 548         struct ablkcipher_request *abreq = &pctx->u.abreq;
 549         struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
 550         int err;
 551
 552         crypto_gcm_init_crypt(abreq, req, req->cryptlen);
 553         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 554                                         gcm_encrypt_done, req);
 555
 556         gctx->src = req->dst;
 557         gctx->cryptlen = req->cryptlen;
 558         gctx->complete = gcm_enc_hash_done;
 559
 560         err = crypto_ablkcipher_encrypt(abreq);
 561         if (err)
 562                 return err;
 563
 564         err = gcm_hash(req, pctx);
 565         if (err)
 566                 return err;
 567
 568         crypto_xor(pctx->auth_tag, pctx->iauth_tag, 16);
 569         gcm_enc_copy_hash(req, pctx);
 570
 571         return 0;
 572 }
 573
 574 static int crypto_gcm_verify(struct aead_request *req,
 575                              struct crypto_gcm_req_priv_ctx *pctx)
 576 {
 577         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 578         u8 *auth_tag = pctx->auth_tag;
 579         u8 *iauth_tag = pctx->iauth_tag;
 580         unsigned int authsize = crypto_aead_authsize(aead);
 581         unsigned int cryptlen = req->cryptlen - authsize;
 582
 583         crypto_xor(auth_tag, iauth_tag, 16);
 584         scatterwalk_map_and_copy(iauth_tag, req->src, cryptlen, authsize, 0);
 585         return memcmp(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
 586 }
 587
 588 static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
 589 {
 590         struct aead_request *req = areq->data;
 591         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 592
 593         if (!err)
 594                 err = crypto_gcm_verify(req, pctx);
 595
 596         aead_request_complete(req, err);
 597 }
 598
 599 static void gcm_dec_hash_done(struct aead_request *req, int err)
 600 {
 601         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 602         struct ablkcipher_request *abreq = &pctx->u.abreq;
 603         struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
 604
 605         if (!err) {
 606                 ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 607                                                 gcm_decrypt_done, req);
 608                 crypto_gcm_init_crypt(abreq, req, gctx->cryptlen);
 609                 err = crypto_ablkcipher_decrypt(abreq);
 610                 if (err == -EINPROGRESS || err == -EBUSY)
 611                         return;
 612                 else if (!err)
 613                         err = crypto_gcm_verify(req, pctx);
 614         }
 615
 616         aead_request_complete(req, err);
 617 }
 618
 619 static int crypto_gcm_decrypt(struct aead_request *req)
 620 {
 621         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 622         struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
 623         struct ablkcipher_request *abreq = &pctx->u.abreq;
 624         struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
 625         unsigned int authsize = crypto_aead_authsize(aead);
 626         unsigned int cryptlen = req->cryptlen;
 627         int err;
 628
 629         if (cryptlen < authsize)
 630                 return -EINVAL;
 631         cryptlen -= authsize;
 632
 633         gctx->src = req->src;
 634         gctx->cryptlen = cryptlen;
 635         gctx->complete = gcm_dec_hash_done;
 636
 637         err = gcm_hash(req, pctx);
 638         if (err)
 639                 return err;
 640
 641         ablkcipher_request_set_callback(abreq, aead_request_flags(req),
 642                                         gcm_decrypt_done, req);
 643         crypto_gcm_init_crypt(abreq, req, cryptlen);
 644         err = crypto_ablkcipher_decrypt(abreq);
 645         if (err)
 646                 return err;
 647
 648         return crypto_gcm_verify(req, pctx);
 649 }
 650
 651 static int crypto_gcm_init_tfm(struct crypto_tfm *tfm)
 652 {
 653         struct crypto_instance *inst = (void *)tfm->__crt_alg;
 654         struct gcm_instance_ctx *ictx = crypto_instance_ctx(inst);
 655         struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(tfm);
 656         struct crypto_ablkcipher *ctr;
 657         struct crypto_ahash *ghash;
 658         unsigned long align;
 659         int err;
 660
 661         ghash = crypto_spawn_ahash(&ictx->ghash);
 662         if (IS_ERR(ghash))
 663                 return PTR_ERR(ghash);
 664
 665         ctr = crypto_spawn_skcipher(&ictx->ctr);
 666         err = PTR_ERR(ctr);
 667         if (IS_ERR(ctr))
 668                 goto err_free_hash;
 669
 670         ctx->ctr = ctr;
 671         ctx->ghash = ghash;
 672
 673         align = crypto_tfm_alg_alignmask(tfm);
 674         align &= ~(crypto_tfm_ctx_alignment() - 1);
 675         tfm->crt_aead.reqsize = align +
 676                 offsetof(struct crypto_gcm_req_priv_ctx, u) +
 677                 max(sizeof(struct ablkcipher_request) +
 678                     crypto_ablkcipher_reqsize(ctr),
 679                     sizeof(struct ahash_request) +
 680                     crypto_ahash_reqsize(ghash));
 681
 682         return 0;
 683
 684 err_free_hash:
 685         crypto_free_ahash(ghash);
 686         return err;
 687 }
 688
 689 static void crypto_gcm_exit_tfm(struct crypto_tfm *tfm)
 690 {
 691         struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(tfm);
 692
 693         crypto_free_ahash(ctx->ghash);
 694         crypto_free_ablkcipher(ctx->ctr);
 695 }
 696
 697 static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb,
 698                                                        const char *full_name,
 699                                                        const char *ctr_name,
 700                                                        const char *ghash_name)
 701 {
 702         struct crypto_attr_type *algt;
 703         struct crypto_instance *inst;
 704         struct crypto_alg *ctr;
 705         struct crypto_alg *ghash_alg;
 706         struct ahash_alg *ghash_ahash_alg;
 707         struct gcm_instance_ctx *ctx;
 708         int err;
 709
 710         algt = crypto_get_attr_type(tb);
 711         if (IS_ERR(algt))
 712                 return ERR_CAST(algt);
 713
 714         if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
 715                 return ERR_PTR(-EINVAL);
 716
 717         ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type,
 718                                     CRYPTO_ALG_TYPE_HASH,
 719                                     CRYPTO_ALG_TYPE_AHASH_MASK);
 720         if (IS_ERR(ghash_alg))
 721                 return ERR_CAST(ghash_alg);
 722
 723         err = -ENOMEM;
 724         inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
 725         if (!inst)
 726                 goto out_put_ghash;
 727
 728         ctx = crypto_instance_ctx(inst);
 729         ghash_ahash_alg = container_of(ghash_alg, struct ahash_alg, halg.base);
 730         err = crypto_init_ahash_spawn(&ctx->ghash, &ghash_ahash_alg->halg,
 731                                       inst);
 732         if (err)
 733                 goto err_free_inst;
 734
 735         crypto_set_skcipher_spawn(&ctx->ctr, inst);
 736         err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0,
 737                                    crypto_requires_sync(algt->type,
 738                                                         algt->mask));
 739         if (err)
 740                 goto err_drop_ghash;
 741
 742         ctr = crypto_skcipher_spawn_alg(&ctx->ctr);
 743
 744         /* We only support 16-byte blocks. */
 745         if (ctr->cra_ablkcipher.ivsize != 16)
 746                 goto out_put_ctr;
 747
 748         /* Not a stream cipher? */
 749         err = -EINVAL;
 750         if (ctr->cra_blocksize != 1)
 751                 goto out_put_ctr;
 752
 753         err = -ENAMETOOLONG;
 754         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
 755                      "gcm_base(%s,%s)", ctr->cra_driver_name,
 756                      ghash_alg->cra_driver_name) >=
 757             CRYPTO_MAX_ALG_NAME)
 758                 goto out_put_ctr;
 759
 760         memcpy(inst->alg.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
 761
 762         inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
 763         inst->alg.cra_flags |= ctr->cra_flags & CRYPTO_ALG_ASYNC;
 764         inst->alg.cra_priority = ctr->cra_priority;
 765         inst->alg.cra_blocksize = 1;
 766         inst->alg.cra_alignmask = ctr->cra_alignmask | (__alignof__(u64) - 1);
 767         inst->alg.cra_type = &crypto_aead_type;
 768         inst->alg.cra_aead.ivsize = 16;
 769         inst->alg.cra_aead.maxauthsize = 16;
 770         inst->alg.cra_ctxsize = sizeof(struct crypto_gcm_ctx);
 771         inst->alg.cra_init = crypto_gcm_init_tfm;
 772         inst->alg.cra_exit = crypto_gcm_exit_tfm;
 773         inst->alg.cra_aead.setkey = crypto_gcm_setkey;
 774         inst->alg.cra_aead.setauthsize = crypto_gcm_setauthsize;
 775         inst->alg.cra_aead.encrypt = crypto_gcm_encrypt;
 776         inst->alg.cra_aead.decrypt = crypto_gcm_decrypt;
 777
 778 out:
 779         crypto_mod_put(ghash_alg);
 780         return inst;
 781
 782 out_put_ctr:
 783         crypto_drop_skcipher(&ctx->ctr);
 784 err_drop_ghash:
 785         crypto_drop_ahash(&ctx->ghash);
 786 err_free_inst:
 787         kfree(inst);
 788 out_put_ghash:
 789         inst = ERR_PTR(err);
 790         goto out;
 791 }
 792
 793 static struct crypto_instance *crypto_gcm_alloc(struct rtattr **tb)
 794 {
 795         const char *cipher_name;
 796         char ctr_name[CRYPTO_MAX_ALG_NAME];
 797         char full_name[CRYPTO_MAX_ALG_NAME];
 798
 799         cipher_name = crypto_attr_alg_name(tb[1]);
 800         if (IS_ERR(cipher_name))
 801                 return ERR_CAST(cipher_name);
 802
 803         if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
 804             CRYPTO_MAX_ALG_NAME)
 805                 return ERR_PTR(-ENAMETOOLONG);
 806
 807         if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm(%s)", cipher_name) >=
 808             CRYPTO_MAX_ALG_NAME)
 809                 return ERR_PTR(-ENAMETOOLONG);
 810
 811         return crypto_gcm_alloc_common(tb, full_name, ctr_name, "ghash");
 812 }
 813
 814 static void crypto_gcm_free(struct crypto_instance *inst)
 815 {
 816         struct gcm_instance_ctx *ctx = crypto_instance_ctx(inst);
 817
 818         crypto_drop_skcipher(&ctx->ctr);
 819         crypto_drop_ahash(&ctx->ghash);
 820         kfree(inst);
 821 }
 822
 823 static struct crypto_template crypto_gcm_tmpl = {
 824         .name = "gcm",
 825         .alloc = crypto_gcm_alloc,
 826         .free = crypto_gcm_free,
 827         .module = THIS_MODULE,
 828 };
 829
 830 static struct crypto_instance *crypto_gcm_base_alloc(struct rtattr **tb)
 831 {
 832         const char *ctr_name;
 833         const char *ghash_name;
 834         char full_name[CRYPTO_MAX_ALG_NAME];
 835
 836         ctr_name = crypto_attr_alg_name(tb[1]);
 837         if (IS_ERR(ctr_name))
 838                 return ERR_CAST(ctr_name);
 839
 840         ghash_name = crypto_attr_alg_name(tb[2]);
 841         if (IS_ERR(ghash_name))
 842                 return ERR_CAST(ghash_name);
 843
 844         if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)",
 845                      ctr_name, ghash_name) >= CRYPTO_MAX_ALG_NAME)
 846                 return ERR_PTR(-ENAMETOOLONG);
 847
 848         return crypto_gcm_alloc_common(tb, full_name, ctr_name, ghash_name);
 849 }
 850
 851 static struct crypto_template crypto_gcm_base_tmpl = {
 852         .name = "gcm_base",
 853         .alloc = crypto_gcm_base_alloc,
 854         .free = crypto_gcm_free,
 855         .module = THIS_MODULE,
 856 };
 857
 858 static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
 859                                  unsigned int keylen)
 860 {
 861         struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
 862         struct crypto_aead *child = ctx->child;
 863         int err;
 864
 865         if (keylen < 4)
 866                 return -EINVAL;
 867
 868         keylen -= 4;
 869         memcpy(ctx->nonce, key + keylen, 4);
 870
 871         crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
 872         crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
 873                                      CRYPTO_TFM_REQ_MASK);
 874         err = crypto_aead_setkey(child, key, keylen);
 875         crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
 876                                       CRYPTO_TFM_RES_MASK);
 877
 878         return err;
 879 }
 880
 881 static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
 882                                       unsigned int authsize)
 883 {
 884         struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
 885
 886         switch (authsize) {
 887         case 8:
 888         case 12:
 889         case 16:
 890                 break;
 891         default:
 892                 return -EINVAL;
 893         }
 894
 895         return crypto_aead_setauthsize(ctx->child, authsize);
 896 }
 897
 898 static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
 899 {
 900         struct aead_request *subreq = aead_request_ctx(req);
 901         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 902         struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead);
 903         struct crypto_aead *child = ctx->child;
 904         u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
 905                            crypto_aead_alignmask(child) + 1);
 906
 907         memcpy(iv, ctx->nonce, 4);
 908         memcpy(iv + 4, req->iv, 8);
 909
 910         aead_request_set_tfm(subreq, child);
 911         aead_request_set_callback(subreq, req->base.flags, req->base.complete,
 912                                   req->base.data);
 913         aead_request_set_crypt(subreq, req->src, req->dst, req->cryptlen, iv);
 914         aead_request_set_assoc(subreq, req->assoc, req->assoclen);
 915
 916         return subreq;
 917 }
 918
 919 static int crypto_rfc4106_encrypt(struct aead_request *req)
 920 {
 921         req = crypto_rfc4106_crypt(req);
 922
 923         return crypto_aead_encrypt(req);
 924 }
 925
 926 static int crypto_rfc4106_decrypt(struct aead_request *req)
 927 {
 928         req = crypto_rfc4106_crypt(req);
 929
 930         return crypto_aead_decrypt(req);
 931 }
 932
 933 static int crypto_rfc4106_init_tfm(struct crypto_tfm *tfm)
 934 {
 935         struct crypto_instance *inst = (void *)tfm->__crt_alg;
 936         struct crypto_aead_spawn *spawn = crypto_instance_ctx(inst);
 937         struct crypto_rfc4106_ctx *ctx = crypto_tfm_ctx(tfm);
 938         struct crypto_aead *aead;
 939         unsigned long align;
 940
 941         aead = crypto_spawn_aead(spawn);
 942         if (IS_ERR(aead))
 943                 return PTR_ERR(aead);
 944
 945         ctx->child = aead;
 946
 947         align = crypto_aead_alignmask(aead);
 948         align &= ~(crypto_tfm_ctx_alignment() - 1);
 949         tfm->crt_aead.reqsize = sizeof(struct aead_request) +
 950                                 ALIGN(crypto_aead_reqsize(aead),
 951                                       crypto_tfm_ctx_alignment()) +
 952                                 align + 16;
 953
 954         return 0;
 955 }
 956
 957 static void crypto_rfc4106_exit_tfm(struct crypto_tfm *tfm)
 958 {
 959         struct crypto_rfc4106_ctx *ctx = crypto_tfm_ctx(tfm);
 960
 961         crypto_free_aead(ctx->child);
 962 }
 963
 964 static struct crypto_instance *crypto_rfc4106_alloc(struct rtattr **tb)
 965 {
 966         struct crypto_attr_type *algt;
 967         struct crypto_instance *inst;
 968         struct crypto_aead_spawn *spawn;
 969         struct crypto_alg *alg;
 970         const char *ccm_name;
 971         int err;
 972
 973         algt = crypto_get_attr_type(tb);
 974         if (IS_ERR(algt))
 975                 return ERR_CAST(algt);
 976
 977         if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
 978                 return ERR_PTR(-EINVAL);
 979
 980         ccm_name = crypto_attr_alg_name(tb[1]);
 981         if (IS_ERR(ccm_name))
 982                 return ERR_CAST(ccm_name);
 983
 984         inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
 985         if (!inst)
 986                 return ERR_PTR(-ENOMEM);
 987
 988         spawn = crypto_instance_ctx(inst);
 989         crypto_set_aead_spawn(spawn, inst);
 990         err = crypto_grab_aead(spawn, ccm_name, 0,
 991                                crypto_requires_sync(algt->type, algt->mask));
 992         if (err)
 993                 goto out_free_inst;
 994
 995         alg = crypto_aead_spawn_alg(spawn);
 996
 997         err = -EINVAL;
 998
 999         /* We only support 16-byte blocks. */
1000         if (alg->cra_aead.ivsize != 16)
1001                 goto out_drop_alg;
1002
1003         /* Not a stream cipher? */
1004         if (alg->cra_blocksize != 1)
1005                 goto out_drop_alg;
1006
1007         err = -ENAMETOOLONG;
1008         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
1009                      "rfc4106(%s)", alg->cra_name) >= CRYPTO_MAX_ALG_NAME ||
1010             snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
1011                      "rfc4106(%s)", alg->cra_driver_name) >=
1012             CRYPTO_MAX_ALG_NAME)
1013                 goto out_drop_alg;
1014
1015         inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
1016         inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC;
1017         inst->alg.cra_priority = alg->cra_priority;
1018         inst->alg.cra_blocksize = 1;
1019         inst->alg.cra_alignmask = alg->cra_alignmask;
1020         inst->alg.cra_type = &crypto_nivaead_type;
1021
1022         inst->alg.cra_aead.ivsize = 8;
1023         inst->alg.cra_aead.maxauthsize = 16;
1024
1025         inst->alg.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
1026
1027         inst->alg.cra_init = crypto_rfc4106_init_tfm;
1028         inst->alg.cra_exit = crypto_rfc4106_exit_tfm;
1029
1030         inst->alg.cra_aead.setkey = crypto_rfc4106_setkey;
1031         inst->alg.cra_aead.setauthsize = crypto_rfc4106_setauthsize;
1032         inst->alg.cra_aead.encrypt = crypto_rfc4106_encrypt;
1033         inst->alg.cra_aead.decrypt = crypto_rfc4106_decrypt;
1034
1035         inst->alg.cra_aead.geniv = "seqiv";
1036
1037 out:
1038         return inst;
1039
1040 out_drop_alg:
1041         crypto_drop_aead(spawn);
1042 out_free_inst:
1043         kfree(inst);
1044         inst = ERR_PTR(err);
1045         goto out;
1046 }
1047
1048 static void crypto_rfc4106_free(struct crypto_instance *inst)
1049 {
1050         crypto_drop_spawn(crypto_instance_ctx(inst));
1051         kfree(inst);
1052 }
1053
1054 static struct crypto_template crypto_rfc4106_tmpl = {
1055         .name = "rfc4106",
1056         .alloc = crypto_rfc4106_alloc,
1057         .free = crypto_rfc4106_free,
1058         .module = THIS_MODULE,
1059 };
1060
1061 static inline struct crypto_rfc4543_req_ctx *crypto_rfc4543_reqctx(
1062         struct aead_request *req)
1063 {
1064         unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
1065
1066         return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
1067 }
1068
1069 static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
1070                                  unsigned int keylen)
1071 {
1072         struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
1073         struct crypto_aead *child = ctx->child;
1074         int err;
1075
1076         if (keylen < 4)
1077                 return -EINVAL;
1078
1079         keylen -= 4;
1080         memcpy(ctx->nonce, key + keylen, 4);
1081
1082         crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
1083         crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
1084                                      CRYPTO_TFM_REQ_MASK);
1085         err = crypto_aead_setkey(child, key, keylen);
1086         crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
1087                                       CRYPTO_TFM_RES_MASK);
1088
1089         return err;
1090 }
1091
1092 static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
1093                                       unsigned int authsize)
1094 {
1095         struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
1096
1097         if (authsize != 16)
1098                 return -EINVAL;
1099
1100         return crypto_aead_setauthsize(ctx->child, authsize);
1101 }
1102
1103 static void crypto_rfc4543_done(struct crypto_async_request *areq, int err)
1104 {
1105         struct aead_request *req = areq->data;
1106         struct crypto_aead *aead = crypto_aead_reqtfm(req);
1107         struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req);
1108
1109         if (!err) {
1110                 scatterwalk_map_and_copy(rctx->auth_tag, req->dst,
1111                                          req->cryptlen,
1112                                          crypto_aead_authsize(aead), 1);
1113         }
1114
1115         aead_request_complete(req, err);
1116 }
1117
1118 static struct aead_request *crypto_rfc4543_crypt(struct aead_request *req,
1119                                                  bool enc)
1120 {
1121         struct crypto_aead *aead = crypto_aead_reqtfm(req);
1122         struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1123         struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req);
1124         struct aead_request *subreq = &rctx->subreq;
1125         struct scatterlist *src = req->src;
1126         struct scatterlist *cipher = rctx->cipher;
1127         struct scatterlist *payload = rctx->payload;
1128         struct scatterlist *assoc = rctx->assoc;
1129         unsigned int authsize = crypto_aead_authsize(aead);
1130         unsigned int assoclen = req->assoclen;
1131         struct page *srcp;
1132         u8 *vsrc;
1133         u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
1134                            crypto_aead_alignmask(ctx->child) + 1);
1135
1136         memcpy(iv, ctx->nonce, 4);
1137         memcpy(iv + 4, req->iv, 8);
1138
1139         /* construct cipher/plaintext */
1140         if (enc)
1141                 memset(rctx->auth_tag, 0, authsize);
1142         else
1143                 scatterwalk_map_and_copy(rctx->auth_tag, src,
1144                                          req->cryptlen - authsize,
1145                                          authsize, 0);
1146
1147         sg_init_one(cipher, rctx->auth_tag, authsize);
1148
1149         /* construct the aad */
1150         srcp = sg_page(src);
1151         vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
1152
1153         sg_init_table(payload, 2);
1154         sg_set_buf(payload, req->iv, 8);
1155         scatterwalk_crypto_chain(payload, src, vsrc == req->iv + 8, 2);
1156         assoclen += 8 + req->cryptlen - (enc ? 0 : authsize);
1157
1158         if (req->assoc->length == req->assoclen) {
1159                 sg_init_table(assoc, 2);
1160                 sg_set_page(assoc, sg_page(req->assoc), req->assoc->length,
1161                             req->assoc->offset);
1162         } else {
1163                 BUG_ON(req->assoclen > sizeof(rctx->assocbuf));
1164
1165                 scatterwalk_map_and_copy(rctx->assocbuf, req->assoc, 0,
1166                                          req->assoclen, 0);
1167
1168                 sg_init_table(assoc, 2);
1169                 sg_set_buf(assoc, rctx->assocbuf, req->assoclen);
1170         }
1171         scatterwalk_crypto_chain(assoc, payload, 0, 2);
1172
1173         aead_request_set_tfm(subreq, ctx->child);
1174         aead_request_set_callback(subreq, req->base.flags, crypto_rfc4543_done,
1175                                   req);
1176         aead_request_set_crypt(subreq, cipher, cipher, enc ? 0 : authsize, iv);
1177         aead_request_set_assoc(subreq, assoc, assoclen);
1178
1179         return subreq;
1180 }
1181
1182 static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
1183 {
1184         struct crypto_aead *aead = crypto_aead_reqtfm(req);
1185         struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1186         unsigned int authsize = crypto_aead_authsize(aead);
1187         unsigned int nbytes = req->cryptlen - (enc ? 0 : authsize);
1188         struct blkcipher_desc desc = {
1189                 .tfm = ctx->null,
1190         };
1191
1192         return crypto_blkcipher_encrypt(&desc, req->dst, req->src, nbytes);
1193 }
1194
1195 static int crypto_rfc4543_encrypt(struct aead_request *req)
1196 {
1197         struct crypto_aead *aead = crypto_aead_reqtfm(req);
1198         struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req);
1199         struct aead_request *subreq;
1200         int err;
1201
1202         if (req->src != req->dst) {
1203                 err = crypto_rfc4543_copy_src_to_dst(req, true);
1204                 if (err)
1205                         return err;
1206         }
1207
1208         subreq = crypto_rfc4543_crypt(req, true);
1209         err = crypto_aead_encrypt(subreq);
1210         if (err)
1211                 return err;
1212
1213         scatterwalk_map_and_copy(rctx->auth_tag, req->dst, req->cryptlen,
1214                                  crypto_aead_authsize(aead), 1);
1215
1216         return 0;
1217 }
1218
1219 static int crypto_rfc4543_decrypt(struct aead_request *req)
1220 {
1221         int err;
1222
1223         if (req->src != req->dst) {
1224                 err = crypto_rfc4543_copy_src_to_dst(req, false);
1225                 if (err)
1226                         return err;
1227         }
1228
1229         req = crypto_rfc4543_crypt(req, false);
1230
1231         return crypto_aead_decrypt(req);
1232 }
1233
1234 static int crypto_rfc4543_init_tfm(struct crypto_tfm *tfm)
1235 {
1236         struct crypto_instance *inst = (void *)tfm->__crt_alg;
1237         struct crypto_rfc4543_instance_ctx *ictx = crypto_instance_ctx(inst);
1238         struct crypto_aead_spawn *spawn = &ictx->aead;
1239         struct crypto_rfc4543_ctx *ctx = crypto_tfm_ctx(tfm);
1240         struct crypto_aead *aead;
1241         struct crypto_blkcipher *null;
1242         unsigned long align;
1243         int err = 0;
1244
1245         aead = crypto_spawn_aead(spawn);
1246         if (IS_ERR(aead))
1247                 return PTR_ERR(aead);
1248
1249         null = crypto_spawn_blkcipher(&ictx->null.base);
1250         err = PTR_ERR(null);
1251         if (IS_ERR(null))
1252                 goto err_free_aead;
1253
1254         ctx->child = aead;
1255         ctx->null = null;
1256
1257         align = crypto_aead_alignmask(aead);
1258         align &= ~(crypto_tfm_ctx_alignment() - 1);
1259         tfm->crt_aead.reqsize = sizeof(struct crypto_rfc4543_req_ctx) +
1260                                 ALIGN(crypto_aead_reqsize(aead),
1261                                       crypto_tfm_ctx_alignment()) +
1262                                 align + 16;
1263
1264         return 0;
1265
1266 err_free_aead:
1267         crypto_free_aead(aead);
1268         return err;
1269 }
1270
1271 static void crypto_rfc4543_exit_tfm(struct crypto_tfm *tfm)
1272 {
1273         struct crypto_rfc4543_ctx *ctx = crypto_tfm_ctx(tfm);
1274
1275         crypto_free_aead(ctx->child);
1276         crypto_free_blkcipher(ctx->null);
1277 }
1278
1279 static struct crypto_instance *crypto_rfc4543_alloc(struct rtattr **tb)
1280 {
1281         struct crypto_attr_type *algt;
1282         struct crypto_instance *inst;
1283         struct crypto_aead_spawn *spawn;
1284         struct crypto_alg *alg;
1285         struct crypto_rfc4543_instance_ctx *ctx;
1286         const char *ccm_name;
1287         int err;
1288
1289         algt = crypto_get_attr_type(tb);
1290         if (IS_ERR(algt))
1291                 return ERR_CAST(algt);
1292
1293         if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
1294                 return ERR_PTR(-EINVAL);
1295
1296         ccm_name = crypto_attr_alg_name(tb[1]);
1297         if (IS_ERR(ccm_name))
1298                 return ERR_CAST(ccm_name);
1299
1300         inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
1301         if (!inst)
1302                 return ERR_PTR(-ENOMEM);
1303
1304         ctx = crypto_instance_ctx(inst);
1305         spawn = &ctx->aead;
1306         crypto_set_aead_spawn(spawn, inst);
1307         err = crypto_grab_aead(spawn, ccm_name, 0,
1308                                crypto_requires_sync(algt->type, algt->mask));
1309         if (err)
1310                 goto out_free_inst;
1311
1312         alg = crypto_aead_spawn_alg(spawn);
1313
1314         crypto_set_skcipher_spawn(&ctx->null, inst);
1315         err = crypto_grab_skcipher(&ctx->null, "ecb(cipher_null)", 0,
1316                                    CRYPTO_ALG_ASYNC);
1317         if (err)
1318                 goto out_drop_alg;
1319
1320         crypto_skcipher_spawn_alg(&ctx->null);
1321
1322         err = -EINVAL;
1323
1324         /* We only support 16-byte blocks. */
1325         if (alg->cra_aead.ivsize != 16)
1326                 goto out_drop_ecbnull;
1327
1328         /* Not a stream cipher? */
1329         if (alg->cra_blocksize != 1)
1330                 goto out_drop_ecbnull;
1331
1332         err = -ENAMETOOLONG;
1333         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
1334                      "rfc4543(%s)", alg->cra_name) >= CRYPTO_MAX_ALG_NAME ||
1335             snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
1336                      "rfc4543(%s)", alg->cra_driver_name) >=
1337             CRYPTO_MAX_ALG_NAME)
1338                 goto out_drop_ecbnull;
1339
1340         inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
1341         inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC;
1342         inst->alg.cra_priority = alg->cra_priority;
1343         inst->alg.cra_blocksize = 1;
1344         inst->alg.cra_alignmask = alg->cra_alignmask;
1345         inst->alg.cra_type = &crypto_nivaead_type;
1346
1347         inst->alg.cra_aead.ivsize = 8;
1348         inst->alg.cra_aead.maxauthsize = 16;
1349
1350         inst->alg.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx);
1351
1352         inst->alg.cra_init = crypto_rfc4543_init_tfm;
1353         inst->alg.cra_exit = crypto_rfc4543_exit_tfm;
1354
1355         inst->alg.cra_aead.setkey = crypto_rfc4543_setkey;
1356         inst->alg.cra_aead.setauthsize = crypto_rfc4543_setauthsize;
1357         inst->alg.cra_aead.encrypt = crypto_rfc4543_encrypt;
1358         inst->alg.cra_aead.decrypt = crypto_rfc4543_decrypt;
1359
1360         inst->alg.cra_aead.geniv = "seqiv";
1361
1362 out:
1363         return inst;
1364
1365 out_drop_ecbnull:
1366         crypto_drop_skcipher(&ctx->null);
1367 out_drop_alg:
1368         crypto_drop_aead(spawn);
1369 out_free_inst:
1370         kfree(inst);
1371         inst = ERR_PTR(err);
1372         goto out;
1373 }
1374
1375 static void crypto_rfc4543_free(struct crypto_instance *inst)
1376 {
1377         struct crypto_rfc4543_instance_ctx *ctx = crypto_instance_ctx(inst);
1378
1379         crypto_drop_aead(&ctx->aead);
1380         crypto_drop_skcipher(&ctx->null);
1381
1382         kfree(inst);
1383 }
1384
1385 static struct crypto_template crypto_rfc4543_tmpl = {
1386         .name = "rfc4543",
1387         .alloc = crypto_rfc4543_alloc,
1388         .free = crypto_rfc4543_free,
1389         .module = THIS_MODULE,
1390 };
1391
1392 static int __init crypto_gcm_module_init(void)
1393 {
1394         int err;
1395
1396         gcm_zeroes = kzalloc(16, GFP_KERNEL);
1397         if (!gcm_zeroes)
1398                 return -ENOMEM;
1399
1400         err = crypto_register_template(&crypto_gcm_base_tmpl);
1401         if (err)
1402                 goto out;
1403
1404         err = crypto_register_template(&crypto_gcm_tmpl);
1405         if (err)
1406                 goto out_undo_base;
1407
1408         err = crypto_register_template(&crypto_rfc4106_tmpl);
1409         if (err)
1410                 goto out_undo_gcm;
1411
1412         err = crypto_register_template(&crypto_rfc4543_tmpl);
1413         if (err)
1414                 goto out_undo_rfc4106;
1415
1416         return 0;
1417
1418 out_undo_rfc4106:
1419         crypto_unregister_template(&crypto_rfc4106_tmpl);
1420 out_undo_gcm:
1421         crypto_unregister_template(&crypto_gcm_tmpl);
1422 out_undo_base:
1423         crypto_unregister_template(&crypto_gcm_base_tmpl);
1424 out:
1425         kfree(gcm_zeroes);
1426         return err;
1427 }
1428
1429 static void __exit crypto_gcm_module_exit(void)
1430 {
1431         kfree(gcm_zeroes);
1432         crypto_unregister_template(&crypto_rfc4543_tmpl);
1433         crypto_unregister_template(&crypto_rfc4106_tmpl);
1434         crypto_unregister_template(&crypto_gcm_tmpl);
1435         crypto_unregister_template(&crypto_gcm_base_tmpl);
1436 }
1437
1438 module_init(crypto_gcm_module_init);
1439 module_exit(crypto_gcm_module_exit);
1440
1441 MODULE_LICENSE("GPL");
1442 MODULE_DESCRIPTION("Galois/Counter Mode");
1443 MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
1444 MODULE_ALIAS("gcm_base");
1445 MODULE_ALIAS("rfc4106");
1446 MODULE_ALIAS("rfc4543");