arch/arm64/crypto/aes-neonbs-glue.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Bit sliced AES using NEON instructions
   4  *
   5  * Copyright (C) 2016 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
   6  */
   7
   8 #include <asm/neon.h>
   9 #include <asm/simd.h>
  10 #include <crypto/aes.h>
  11 #include <crypto/internal/simd.h>
  12 #include <crypto/internal/skcipher.h>
  13 #include <crypto/xts.h>
  14 #include <linux/module.h>
  15
  16 #include "aes-ctr-fallback.h"
  17
  18 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
  19 MODULE_LICENSE("GPL v2");
  20
  21 MODULE_ALIAS_CRYPTO("ecb(aes)");
  22 MODULE_ALIAS_CRYPTO("cbc(aes)");
  23 MODULE_ALIAS_CRYPTO("ctr(aes)");
  24 MODULE_ALIAS_CRYPTO("xts(aes)");
  25
  26 asmlinkage void aesbs_convert_key(u8 out[], u32 const rk[], int rounds);
  27
  28 asmlinkage void aesbs_ecb_encrypt(u8 out[], u8 const in[], u8 const rk[],
  29                                   int rounds, int blocks);
  30 asmlinkage void aesbs_ecb_decrypt(u8 out[], u8 const in[], u8 const rk[],
  31                                   int rounds, int blocks);
  32
  33 asmlinkage void aesbs_cbc_decrypt(u8 out[], u8 const in[], u8 const rk[],
  34                                   int rounds, int blocks, u8 iv[]);
  35
  36 asmlinkage void aesbs_ctr_encrypt(u8 out[], u8 const in[], u8 const rk[],
  37                                   int rounds, int blocks, u8 iv[], u8 final[]);
  38
  39 asmlinkage void aesbs_xts_encrypt(u8 out[], u8 const in[], u8 const rk[],
  40                                   int rounds, int blocks, u8 iv[]);
  41 asmlinkage void aesbs_xts_decrypt(u8 out[], u8 const in[], u8 const rk[],
  42                                   int rounds, int blocks, u8 iv[]);
  43
  44 /* borrowed from aes-neon-blk.ko */
  45 asmlinkage void neon_aes_ecb_encrypt(u8 out[], u8 const in[], u32 const rk[],
  46                                      int rounds, int blocks);
  47 asmlinkage void neon_aes_cbc_encrypt(u8 out[], u8 const in[], u32 const rk[],
  48                                      int rounds, int blocks, u8 iv[]);
  49
  50 struct aesbs_ctx {
  51         u8      rk[13 * (8 * AES_BLOCK_SIZE) + 32];
  52         int     rounds;
  53 } __aligned(AES_BLOCK_SIZE);
  54
  55 struct aesbs_cbc_ctx {
  56         struct aesbs_ctx        key;
  57         u32                     enc[AES_MAX_KEYLENGTH_U32];
  58 };
  59
  60 struct aesbs_ctr_ctx {
  61         struct aesbs_ctx        key;            /* must be first member */
  62         struct crypto_aes_ctx   fallback;
  63 };
  64
  65 struct aesbs_xts_ctx {
  66         struct aesbs_ctx        key;
  67         u32                     twkey[AES_MAX_KEYLENGTH_U32];
  68 };
  69
  70 static int aesbs_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
  71                         unsigned int key_len)
  72 {
  73         struct aesbs_ctx *ctx = crypto_skcipher_ctx(tfm);
  74         struct crypto_aes_ctx rk;
  75         int err;
  76
  77         err = crypto_aes_expand_key(&rk, in_key, key_len);
  78         if (err)
  79                 return err;
  80
  81         ctx->rounds = 6 + key_len / 4;
  82
  83         kernel_neon_begin();
  84         aesbs_convert_key(ctx->rk, rk.key_enc, ctx->rounds);
  85         kernel_neon_end();
  86
  87         return 0;
  88 }
  89
  90 static int __ecb_crypt(struct skcipher_request *req,
  91                        void (*fn)(u8 out[], u8 const in[], u8 const rk[],
  92                                   int rounds, int blocks))
  93 {
  94         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  95         struct aesbs_ctx *ctx = crypto_skcipher_ctx(tfm);
  96         struct skcipher_walk walk;
  97         int err;
  98
  99         err = skcipher_walk_virt(&walk, req, false);
 100
 101         while (walk.nbytes >= AES_BLOCK_SIZE) {
 102                 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
 103
 104                 if (walk.nbytes < walk.total)
 105                         blocks = round_down(blocks,
 106                                             walk.stride / AES_BLOCK_SIZE);
 107
 108                 kernel_neon_begin();
 109                 fn(walk.dst.virt.addr, walk.src.virt.addr, ctx->rk,
 110                    ctx->rounds, blocks);
 111                 kernel_neon_end();
 112                 err = skcipher_walk_done(&walk,
 113                                          walk.nbytes - blocks * AES_BLOCK_SIZE);
 114         }
 115
 116         return err;
 117 }
 118
 119 static int ecb_encrypt(struct skcipher_request *req)
 120 {
 121         return __ecb_crypt(req, aesbs_ecb_encrypt);
 122 }
 123
 124 static int ecb_decrypt(struct skcipher_request *req)
 125 {
 126         return __ecb_crypt(req, aesbs_ecb_decrypt);
 127 }
 128
 129 static int aesbs_cbc_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
 130                             unsigned int key_len)
 131 {
 132         struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
 133         struct crypto_aes_ctx rk;
 134         int err;
 135
 136         err = crypto_aes_expand_key(&rk, in_key, key_len);
 137         if (err)
 138                 return err;
 139
 140         ctx->key.rounds = 6 + key_len / 4;
 141
 142         memcpy(ctx->enc, rk.key_enc, sizeof(ctx->enc));
 143
 144         kernel_neon_begin();
 145         aesbs_convert_key(ctx->key.rk, rk.key_enc, ctx->key.rounds);
 146         kernel_neon_end();
 147
 148         return 0;
 149 }
 150
 151 static int cbc_encrypt(struct skcipher_request *req)
 152 {
 153         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 154         struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
 155         struct skcipher_walk walk;
 156         int err;
 157
 158         err = skcipher_walk_virt(&walk, req, false);
 159
 160         while (walk.nbytes >= AES_BLOCK_SIZE) {
 161                 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
 162
 163                 /* fall back to the non-bitsliced NEON implementation */
 164                 kernel_neon_begin();
 165                 neon_aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
 166                                      ctx->enc, ctx->key.rounds, blocks,
 167                                      walk.iv);
 168                 kernel_neon_end();
 169                 err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
 170         }
 171         return err;
 172 }
 173
 174 static int cbc_decrypt(struct skcipher_request *req)
 175 {
 176         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 177         struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
 178         struct skcipher_walk walk;
 179         int err;
 180
 181         err = skcipher_walk_virt(&walk, req, false);
 182
 183         while (walk.nbytes >= AES_BLOCK_SIZE) {
 184                 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
 185
 186                 if (walk.nbytes < walk.total)
 187                         blocks = round_down(blocks,
 188                                             walk.stride / AES_BLOCK_SIZE);
 189
 190                 kernel_neon_begin();
 191                 aesbs_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
 192                                   ctx->key.rk, ctx->key.rounds, blocks,
 193                                   walk.iv);
 194                 kernel_neon_end();
 195                 err = skcipher_walk_done(&walk,
 196                                          walk.nbytes - blocks * AES_BLOCK_SIZE);
 197         }
 198
 199         return err;
 200 }
 201
 202 static int aesbs_ctr_setkey_sync(struct crypto_skcipher *tfm, const u8 *in_key,
 203                                  unsigned int key_len)
 204 {
 205         struct aesbs_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
 206         int err;
 207
 208         err = crypto_aes_expand_key(&ctx->fallback, in_key, key_len);
 209         if (err)
 210                 return err;
 211
 212         ctx->key.rounds = 6 + key_len / 4;
 213
 214         kernel_neon_begin();
 215         aesbs_convert_key(ctx->key.rk, ctx->fallback.key_enc, ctx->key.rounds);
 216         kernel_neon_end();
 217
 218         return 0;
 219 }
 220
 221 static int ctr_encrypt(struct skcipher_request *req)
 222 {
 223         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 224         struct aesbs_ctx *ctx = crypto_skcipher_ctx(tfm);
 225         struct skcipher_walk walk;
 226         u8 buf[AES_BLOCK_SIZE];
 227         int err;
 228
 229         err = skcipher_walk_virt(&walk, req, false);
 230
 231         while (walk.nbytes > 0) {
 232                 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
 233                 u8 *final = (walk.total % AES_BLOCK_SIZE) ? buf : NULL;
 234
 235                 if (walk.nbytes < walk.total) {
 236                         blocks = round_down(blocks,
 237                                             walk.stride / AES_BLOCK_SIZE);
 238                         final = NULL;
 239                 }
 240
 241                 kernel_neon_begin();
 242                 aesbs_ctr_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
 243                                   ctx->rk, ctx->rounds, blocks, walk.iv, final);
 244                 kernel_neon_end();
 245
 246                 if (final) {
 247                         u8 *dst = walk.dst.virt.addr + blocks * AES_BLOCK_SIZE;
 248                         u8 *src = walk.src.virt.addr + blocks * AES_BLOCK_SIZE;
 249
 250                         crypto_xor_cpy(dst, src, final,
 251                                        walk.total % AES_BLOCK_SIZE);
 252
 253                         err = skcipher_walk_done(&walk, 0);
 254                         break;
 255                 }
 256                 err = skcipher_walk_done(&walk,
 257                                          walk.nbytes - blocks * AES_BLOCK_SIZE);
 258         }
 259         return err;
 260 }
 261
 262 static int aesbs_xts_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
 263                             unsigned int key_len)
 264 {
 265         struct aesbs_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
 266         struct crypto_aes_ctx rk;
 267         int err;
 268
 269         err = xts_verify_key(tfm, in_key, key_len);
 270         if (err)
 271                 return err;
 272
 273         key_len /= 2;
 274         err = crypto_aes_expand_key(&rk, in_key + key_len, key_len);
 275         if (err)
 276                 return err;
 277
 278         memcpy(ctx->twkey, rk.key_enc, sizeof(ctx->twkey));
 279
 280         return aesbs_setkey(tfm, in_key, key_len);
 281 }
 282
 283 static int ctr_encrypt_sync(struct skcipher_request *req)
 284 {
 285         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 286         struct aesbs_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
 287
 288         if (!crypto_simd_usable())
 289                 return aes_ctr_encrypt_fallback(&ctx->fallback, req);
 290
 291         return ctr_encrypt(req);
 292 }
 293
 294 static int __xts_crypt(struct skcipher_request *req,
 295                        void (*fn)(u8 out[], u8 const in[], u8 const rk[],
 296                                   int rounds, int blocks, u8 iv[]))
 297 {
 298         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 299         struct aesbs_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
 300         struct skcipher_walk walk;
 301         int err;
 302
 303         err = skcipher_walk_virt(&walk, req, false);
 304         if (err)
 305                 return err;
 306
 307         kernel_neon_begin();
 308         neon_aes_ecb_encrypt(walk.iv, walk.iv, ctx->twkey, ctx->key.rounds, 1);
 309         kernel_neon_end();
 310
 311         while (walk.nbytes >= AES_BLOCK_SIZE) {
 312                 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
 313
 314                 if (walk.nbytes < walk.total)
 315                         blocks = round_down(blocks,
 316                                             walk.stride / AES_BLOCK_SIZE);
 317
 318                 kernel_neon_begin();
 319                 fn(walk.dst.virt.addr, walk.src.virt.addr, ctx->key.rk,
 320                    ctx->key.rounds, blocks, walk.iv);
 321                 kernel_neon_end();
 322                 err = skcipher_walk_done(&walk,
 323                                          walk.nbytes - blocks * AES_BLOCK_SIZE);
 324         }
 325         return err;
 326 }
 327
 328 static int xts_encrypt(struct skcipher_request *req)
 329 {
 330         return __xts_crypt(req, aesbs_xts_encrypt);
 331 }
 332
 333 static int xts_decrypt(struct skcipher_request *req)
 334 {
 335         return __xts_crypt(req, aesbs_xts_decrypt);
 336 }
 337
 338 static struct skcipher_alg aes_algs[] = { {
 339         .base.cra_name          = "__ecb(aes)",
 340         .base.cra_driver_name   = "__ecb-aes-neonbs",
 341         .base.cra_priority      = 250,
 342         .base.cra_blocksize     = AES_BLOCK_SIZE,
 343         .base.cra_ctxsize       = sizeof(struct aesbs_ctx),
 344         .base.cra_module        = THIS_MODULE,
 345         .base.cra_flags         = CRYPTO_ALG_INTERNAL,
 346
 347         .min_keysize            = AES_MIN_KEY_SIZE,
 348         .max_keysize            = AES_MAX_KEY_SIZE,
 349         .walksize               = 8 * AES_BLOCK_SIZE,
 350         .setkey                 = aesbs_setkey,
 351         .encrypt                = ecb_encrypt,
 352         .decrypt                = ecb_decrypt,
 353 }, {
 354         .base.cra_name          = "__cbc(aes)",
 355         .base.cra_driver_name   = "__cbc-aes-neonbs",
 356         .base.cra_priority      = 250,
 357         .base.cra_blocksize     = AES_BLOCK_SIZE,
 358         .base.cra_ctxsize       = sizeof(struct aesbs_cbc_ctx),
 359         .base.cra_module        = THIS_MODULE,
 360         .base.cra_flags         = CRYPTO_ALG_INTERNAL,
 361
 362         .min_keysize            = AES_MIN_KEY_SIZE,
 363         .max_keysize            = AES_MAX_KEY_SIZE,
 364         .walksize               = 8 * AES_BLOCK_SIZE,
 365         .ivsize                 = AES_BLOCK_SIZE,
 366         .setkey                 = aesbs_cbc_setkey,
 367         .encrypt                = cbc_encrypt,
 368         .decrypt                = cbc_decrypt,
 369 }, {
 370         .base.cra_name          = "__ctr(aes)",
 371         .base.cra_driver_name   = "__ctr-aes-neonbs",
 372         .base.cra_priority      = 250,
 373         .base.cra_blocksize     = 1,
 374         .base.cra_ctxsize       = sizeof(struct aesbs_ctx),
 375         .base.cra_module        = THIS_MODULE,
 376         .base.cra_flags         = CRYPTO_ALG_INTERNAL,
 377
 378         .min_keysize            = AES_MIN_KEY_SIZE,
 379         .max_keysize            = AES_MAX_KEY_SIZE,
 380         .chunksize              = AES_BLOCK_SIZE,
 381         .walksize               = 8 * AES_BLOCK_SIZE,
 382         .ivsize                 = AES_BLOCK_SIZE,
 383         .setkey                 = aesbs_setkey,
 384         .encrypt                = ctr_encrypt,
 385         .decrypt                = ctr_encrypt,
 386 }, {
 387         .base.cra_name          = "ctr(aes)",
 388         .base.cra_driver_name   = "ctr-aes-neonbs",
 389         .base.cra_priority      = 250 - 1,
 390         .base.cra_blocksize     = 1,
 391         .base.cra_ctxsize       = sizeof(struct aesbs_ctr_ctx),
 392         .base.cra_module        = THIS_MODULE,
 393
 394         .min_keysize            = AES_MIN_KEY_SIZE,
 395         .max_keysize            = AES_MAX_KEY_SIZE,
 396         .chunksize              = AES_BLOCK_SIZE,
 397         .walksize               = 8 * AES_BLOCK_SIZE,
 398         .ivsize                 = AES_BLOCK_SIZE,
 399         .setkey                 = aesbs_ctr_setkey_sync,
 400         .encrypt                = ctr_encrypt_sync,
 401         .decrypt                = ctr_encrypt_sync,
 402 }, {
 403         .base.cra_name          = "__xts(aes)",
 404         .base.cra_driver_name   = "__xts-aes-neonbs",
 405         .base.cra_priority      = 250,
 406         .base.cra_blocksize     = AES_BLOCK_SIZE,
 407         .base.cra_ctxsize       = sizeof(struct aesbs_xts_ctx),
 408         .base.cra_module        = THIS_MODULE,
 409         .base.cra_flags         = CRYPTO_ALG_INTERNAL,
 410
 411         .min_keysize            = 2 * AES_MIN_KEY_SIZE,
 412         .max_keysize            = 2 * AES_MAX_KEY_SIZE,
 413         .walksize               = 8 * AES_BLOCK_SIZE,
 414         .ivsize                 = AES_BLOCK_SIZE,
 415         .setkey                 = aesbs_xts_setkey,
 416         .encrypt                = xts_encrypt,
 417         .decrypt                = xts_decrypt,
 418 } };
 419
 420 static struct simd_skcipher_alg *aes_simd_algs[ARRAY_SIZE(aes_algs)];
 421
 422 static void aes_exit(void)
 423 {
 424         int i;
 425
 426         for (i = 0; i < ARRAY_SIZE(aes_simd_algs); i++)
 427                 if (aes_simd_algs[i])
 428                         simd_skcipher_free(aes_simd_algs[i]);
 429
 430         crypto_unregister_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
 431 }
 432
 433 static int __init aes_init(void)
 434 {
 435         struct simd_skcipher_alg *simd;
 436         const char *basename;
 437         const char *algname;
 438         const char *drvname;
 439         int err;
 440         int i;
 441
 442         if (!cpu_have_named_feature(ASIMD))
 443                 return -ENODEV;
 444
 445         err = crypto_register_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
 446         if (err)
 447                 return err;
 448
 449         for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
 450                 if (!(aes_algs[i].base.cra_flags & CRYPTO_ALG_INTERNAL))
 451                         continue;
 452
 453                 algname = aes_algs[i].base.cra_name + 2;
 454                 drvname = aes_algs[i].base.cra_driver_name + 2;
 455                 basename = aes_algs[i].base.cra_driver_name;
 456                 simd = simd_skcipher_create_compat(algname, drvname, basename);
 457                 err = PTR_ERR(simd);
 458                 if (IS_ERR(simd))
 459                         goto unregister_simds;
 460
 461                 aes_simd_algs[i] = simd;
 462         }
 463         return 0;
 464
 465 unregister_simds:
 466         aes_exit();
 467         return err;
 468 }
 469
 470 module_init(aes_init);
 471 module_exit(aes_exit);