1 /* 2 * Cryptographic API. 3 * 4 * s390 implementation of the AES Cipher Algorithm. 5 * 6 * s390 Version: 7 * Copyright IBM Corp. 2005, 2007 8 * Author(s): Jan Glauber (jang@de.ibm.com) 9 * Sebastian Siewior (sebastian@breakpoint.cc> SW-Fallback 10 * 11 * Derived from "crypto/aes_generic.c" 12 * 13 * This program is free software; you can redistribute it and/or modify it 14 * under the terms of the GNU General Public License as published by the Free 15 * Software Foundation; either version 2 of the License, or (at your option) 16 * any later version. 17 * 18 */ 19 20 #define KMSG_COMPONENT "aes_s390" 21 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 22 23 #include <crypto/aes.h> 24 #include <crypto/algapi.h> 25 #include <linux/err.h> 26 #include <linux/module.h> 27 #include <linux/init.h> 28 #include <linux/spinlock.h> 29 #include "crypt_s390.h" 30 31 #define AES_KEYLEN_128 1 32 #define AES_KEYLEN_192 2 33 #define AES_KEYLEN_256 4 34 35 static u8 *ctrblk; 36 static DEFINE_SPINLOCK(ctrblk_lock); 37 static char keylen_flag; 38 39 struct s390_aes_ctx { 40 u8 key[AES_MAX_KEY_SIZE]; 41 long enc; 42 long dec; 43 int key_len; 44 union { 45 struct crypto_blkcipher *blk; 46 struct crypto_cipher *cip; 47 } fallback; 48 }; 49 50 struct pcc_param { 51 u8 key[32]; 52 u8 tweak[16]; 53 u8 block[16]; 54 u8 bit[16]; 55 u8 xts[16]; 56 }; 57 58 struct s390_xts_ctx { 59 u8 key[32]; 60 u8 pcc_key[32]; 61 long enc; 62 long dec; 63 int key_len; 64 struct crypto_blkcipher *fallback; 65 }; 66 67 /* 68 * Check if the key_len is supported by the HW. 69 * Returns 0 if it is, a positive number if it is not and software fallback is 70 * required or a negative number in case the key size is not valid 71 */ 72 static int need_fallback(unsigned int key_len) 73 { 74 switch (key_len) { 75 case 16: 76 if (!(keylen_flag & AES_KEYLEN_128)) 77 return 1; 78 break; 79 case 24: 80 if (!(keylen_flag & AES_KEYLEN_192)) 81 return 1; 82 break; 83 case 32: 84 if (!(keylen_flag & AES_KEYLEN_256)) 85 return 1; 86 break; 87 default: 88 return -1; 89 break; 90 } 91 return 0; 92 } 93 94 static int setkey_fallback_cip(struct crypto_tfm *tfm, const u8 *in_key, 95 unsigned int key_len) 96 { 97 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 98 int ret; 99 100 sctx->fallback.cip->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; 101 sctx->fallback.cip->base.crt_flags |= (tfm->crt_flags & 102 CRYPTO_TFM_REQ_MASK); 103 104 ret = crypto_cipher_setkey(sctx->fallback.cip, in_key, key_len); 105 if (ret) { 106 tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK; 107 tfm->crt_flags |= (sctx->fallback.cip->base.crt_flags & 108 CRYPTO_TFM_RES_MASK); 109 } 110 return ret; 111 } 112 113 static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, 114 unsigned int key_len) 115 { 116 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 117 u32 *flags = &tfm->crt_flags; 118 int ret; 119 120 ret = need_fallback(key_len); 121 if (ret < 0) { 122 *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; 123 return -EINVAL; 124 } 125 126 sctx->key_len = key_len; 127 if (!ret) { 128 memcpy(sctx->key, in_key, key_len); 129 return 0; 130 } 131 132 return setkey_fallback_cip(tfm, in_key, key_len); 133 } 134 135 static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) 136 { 137 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 138 139 if (unlikely(need_fallback(sctx->key_len))) { 140 crypto_cipher_encrypt_one(sctx->fallback.cip, out, in); 141 return; 142 } 143 144 switch (sctx->key_len) { 145 case 16: 146 crypt_s390_km(KM_AES_128_ENCRYPT, &sctx->key, out, in, 147 AES_BLOCK_SIZE); 148 break; 149 case 24: 150 crypt_s390_km(KM_AES_192_ENCRYPT, &sctx->key, out, in, 151 AES_BLOCK_SIZE); 152 break; 153 case 32: 154 crypt_s390_km(KM_AES_256_ENCRYPT, &sctx->key, out, in, 155 AES_BLOCK_SIZE); 156 break; 157 } 158 } 159 160 static void aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) 161 { 162 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 163 164 if (unlikely(need_fallback(sctx->key_len))) { 165 crypto_cipher_decrypt_one(sctx->fallback.cip, out, in); 166 return; 167 } 168 169 switch (sctx->key_len) { 170 case 16: 171 crypt_s390_km(KM_AES_128_DECRYPT, &sctx->key, out, in, 172 AES_BLOCK_SIZE); 173 break; 174 case 24: 175 crypt_s390_km(KM_AES_192_DECRYPT, &sctx->key, out, in, 176 AES_BLOCK_SIZE); 177 break; 178 case 32: 179 crypt_s390_km(KM_AES_256_DECRYPT, &sctx->key, out, in, 180 AES_BLOCK_SIZE); 181 break; 182 } 183 } 184 185 static int fallback_init_cip(struct crypto_tfm *tfm) 186 { 187 const char *name = tfm->__crt_alg->cra_name; 188 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 189 190 sctx->fallback.cip = crypto_alloc_cipher(name, 0, 191 CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK); 192 193 if (IS_ERR(sctx->fallback.cip)) { 194 pr_err("Allocating AES fallback algorithm %s failed\n", 195 name); 196 return PTR_ERR(sctx->fallback.cip); 197 } 198 199 return 0; 200 } 201 202 static void fallback_exit_cip(struct crypto_tfm *tfm) 203 { 204 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 205 206 crypto_free_cipher(sctx->fallback.cip); 207 sctx->fallback.cip = NULL; 208 } 209 210 static struct crypto_alg aes_alg = { 211 .cra_name = "aes", 212 .cra_driver_name = "aes-s390", 213 .cra_priority = CRYPT_S390_PRIORITY, 214 .cra_flags = CRYPTO_ALG_TYPE_CIPHER | 215 CRYPTO_ALG_NEED_FALLBACK, 216 .cra_blocksize = AES_BLOCK_SIZE, 217 .cra_ctxsize = sizeof(struct s390_aes_ctx), 218 .cra_module = THIS_MODULE, 219 .cra_init = fallback_init_cip, 220 .cra_exit = fallback_exit_cip, 221 .cra_u = { 222 .cipher = { 223 .cia_min_keysize = AES_MIN_KEY_SIZE, 224 .cia_max_keysize = AES_MAX_KEY_SIZE, 225 .cia_setkey = aes_set_key, 226 .cia_encrypt = aes_encrypt, 227 .cia_decrypt = aes_decrypt, 228 } 229 } 230 }; 231 232 static int setkey_fallback_blk(struct crypto_tfm *tfm, const u8 *key, 233 unsigned int len) 234 { 235 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 236 unsigned int ret; 237 238 sctx->fallback.blk->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; 239 sctx->fallback.blk->base.crt_flags |= (tfm->crt_flags & 240 CRYPTO_TFM_REQ_MASK); 241 242 ret = crypto_blkcipher_setkey(sctx->fallback.blk, key, len); 243 if (ret) { 244 tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK; 245 tfm->crt_flags |= (sctx->fallback.blk->base.crt_flags & 246 CRYPTO_TFM_RES_MASK); 247 } 248 return ret; 249 } 250 251 static int fallback_blk_dec(struct blkcipher_desc *desc, 252 struct scatterlist *dst, struct scatterlist *src, 253 unsigned int nbytes) 254 { 255 unsigned int ret; 256 struct crypto_blkcipher *tfm; 257 struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); 258 259 tfm = desc->tfm; 260 desc->tfm = sctx->fallback.blk; 261 262 ret = crypto_blkcipher_decrypt_iv(desc, dst, src, nbytes); 263 264 desc->tfm = tfm; 265 return ret; 266 } 267 268 static int fallback_blk_enc(struct blkcipher_desc *desc, 269 struct scatterlist *dst, struct scatterlist *src, 270 unsigned int nbytes) 271 { 272 unsigned int ret; 273 struct crypto_blkcipher *tfm; 274 struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); 275 276 tfm = desc->tfm; 277 desc->tfm = sctx->fallback.blk; 278 279 ret = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes); 280 281 desc->tfm = tfm; 282 return ret; 283 } 284 285 static int ecb_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, 286 unsigned int key_len) 287 { 288 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 289 int ret; 290 291 ret = need_fallback(key_len); 292 if (ret > 0) { 293 sctx->key_len = key_len; 294 return setkey_fallback_blk(tfm, in_key, key_len); 295 } 296 297 switch (key_len) { 298 case 16: 299 sctx->enc = KM_AES_128_ENCRYPT; 300 sctx->dec = KM_AES_128_DECRYPT; 301 break; 302 case 24: 303 sctx->enc = KM_AES_192_ENCRYPT; 304 sctx->dec = KM_AES_192_DECRYPT; 305 break; 306 case 32: 307 sctx->enc = KM_AES_256_ENCRYPT; 308 sctx->dec = KM_AES_256_DECRYPT; 309 break; 310 } 311 312 return aes_set_key(tfm, in_key, key_len); 313 } 314 315 static int ecb_aes_crypt(struct blkcipher_desc *desc, long func, void *param, 316 struct blkcipher_walk *walk) 317 { 318 int ret = blkcipher_walk_virt(desc, walk); 319 unsigned int nbytes; 320 321 while ((nbytes = walk->nbytes)) { 322 /* only use complete blocks */ 323 unsigned int n = nbytes & ~(AES_BLOCK_SIZE - 1); 324 u8 *out = walk->dst.virt.addr; 325 u8 *in = walk->src.virt.addr; 326 327 ret = crypt_s390_km(func, param, out, in, n); 328 if (ret < 0 || ret != n) 329 return -EIO; 330 331 nbytes &= AES_BLOCK_SIZE - 1; 332 ret = blkcipher_walk_done(desc, walk, nbytes); 333 } 334 335 return ret; 336 } 337 338 static int ecb_aes_encrypt(struct blkcipher_desc *desc, 339 struct scatterlist *dst, struct scatterlist *src, 340 unsigned int nbytes) 341 { 342 struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); 343 struct blkcipher_walk walk; 344 345 if (unlikely(need_fallback(sctx->key_len))) 346 return fallback_blk_enc(desc, dst, src, nbytes); 347 348 blkcipher_walk_init(&walk, dst, src, nbytes); 349 return ecb_aes_crypt(desc, sctx->enc, sctx->key, &walk); 350 } 351 352 static int ecb_aes_decrypt(struct blkcipher_desc *desc, 353 struct scatterlist *dst, struct scatterlist *src, 354 unsigned int nbytes) 355 { 356 struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); 357 struct blkcipher_walk walk; 358 359 if (unlikely(need_fallback(sctx->key_len))) 360 return fallback_blk_dec(desc, dst, src, nbytes); 361 362 blkcipher_walk_init(&walk, dst, src, nbytes); 363 return ecb_aes_crypt(desc, sctx->dec, sctx->key, &walk); 364 } 365 366 static int fallback_init_blk(struct crypto_tfm *tfm) 367 { 368 const char *name = tfm->__crt_alg->cra_name; 369 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 370 371 sctx->fallback.blk = crypto_alloc_blkcipher(name, 0, 372 CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK); 373 374 if (IS_ERR(sctx->fallback.blk)) { 375 pr_err("Allocating AES fallback algorithm %s failed\n", 376 name); 377 return PTR_ERR(sctx->fallback.blk); 378 } 379 380 return 0; 381 } 382 383 static void fallback_exit_blk(struct crypto_tfm *tfm) 384 { 385 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 386 387 crypto_free_blkcipher(sctx->fallback.blk); 388 sctx->fallback.blk = NULL; 389 } 390 391 static struct crypto_alg ecb_aes_alg = { 392 .cra_name = "ecb(aes)", 393 .cra_driver_name = "ecb-aes-s390", 394 .cra_priority = CRYPT_S390_COMPOSITE_PRIORITY, 395 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | 396 CRYPTO_ALG_NEED_FALLBACK, 397 .cra_blocksize = AES_BLOCK_SIZE, 398 .cra_ctxsize = sizeof(struct s390_aes_ctx), 399 .cra_type = &crypto_blkcipher_type, 400 .cra_module = THIS_MODULE, 401 .cra_init = fallback_init_blk, 402 .cra_exit = fallback_exit_blk, 403 .cra_u = { 404 .blkcipher = { 405 .min_keysize = AES_MIN_KEY_SIZE, 406 .max_keysize = AES_MAX_KEY_SIZE, 407 .setkey = ecb_aes_set_key, 408 .encrypt = ecb_aes_encrypt, 409 .decrypt = ecb_aes_decrypt, 410 } 411 } 412 }; 413 414 static int cbc_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, 415 unsigned int key_len) 416 { 417 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 418 int ret; 419 420 ret = need_fallback(key_len); 421 if (ret > 0) { 422 sctx->key_len = key_len; 423 return setkey_fallback_blk(tfm, in_key, key_len); 424 } 425 426 switch (key_len) { 427 case 16: 428 sctx->enc = KMC_AES_128_ENCRYPT; 429 sctx->dec = KMC_AES_128_DECRYPT; 430 break; 431 case 24: 432 sctx->enc = KMC_AES_192_ENCRYPT; 433 sctx->dec = KMC_AES_192_DECRYPT; 434 break; 435 case 32: 436 sctx->enc = KMC_AES_256_ENCRYPT; 437 sctx->dec = KMC_AES_256_DECRYPT; 438 break; 439 } 440 441 return aes_set_key(tfm, in_key, key_len); 442 } 443 444 static int cbc_aes_crypt(struct blkcipher_desc *desc, long func, 445 struct blkcipher_walk *walk) 446 { 447 struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); 448 int ret = blkcipher_walk_virt(desc, walk); 449 unsigned int nbytes = walk->nbytes; 450 struct { 451 u8 iv[AES_BLOCK_SIZE]; 452 u8 key[AES_MAX_KEY_SIZE]; 453 } param; 454 455 if (!nbytes) 456 goto out; 457 458 memcpy(param.iv, walk->iv, AES_BLOCK_SIZE); 459 memcpy(param.key, sctx->key, sctx->key_len); 460 do { 461 /* only use complete blocks */ 462 unsigned int n = nbytes & ~(AES_BLOCK_SIZE - 1); 463 u8 *out = walk->dst.virt.addr; 464 u8 *in = walk->src.virt.addr; 465 466 ret = crypt_s390_kmc(func, ¶m, out, in, n); 467 if (ret < 0 || ret != n) 468 return -EIO; 469 470 nbytes &= AES_BLOCK_SIZE - 1; 471 ret = blkcipher_walk_done(desc, walk, nbytes); 472 } while ((nbytes = walk->nbytes)); 473 memcpy(walk->iv, param.iv, AES_BLOCK_SIZE); 474 475 out: 476 return ret; 477 } 478 479 static int cbc_aes_encrypt(struct blkcipher_desc *desc, 480 struct scatterlist *dst, struct scatterlist *src, 481 unsigned int nbytes) 482 { 483 struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); 484 struct blkcipher_walk walk; 485 486 if (unlikely(need_fallback(sctx->key_len))) 487 return fallback_blk_enc(desc, dst, src, nbytes); 488 489 blkcipher_walk_init(&walk, dst, src, nbytes); 490 return cbc_aes_crypt(desc, sctx->enc, &walk); 491 } 492 493 static int cbc_aes_decrypt(struct blkcipher_desc *desc, 494 struct scatterlist *dst, struct scatterlist *src, 495 unsigned int nbytes) 496 { 497 struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); 498 struct blkcipher_walk walk; 499 500 if (unlikely(need_fallback(sctx->key_len))) 501 return fallback_blk_dec(desc, dst, src, nbytes); 502 503 blkcipher_walk_init(&walk, dst, src, nbytes); 504 return cbc_aes_crypt(desc, sctx->dec, &walk); 505 } 506 507 static struct crypto_alg cbc_aes_alg = { 508 .cra_name = "cbc(aes)", 509 .cra_driver_name = "cbc-aes-s390", 510 .cra_priority = CRYPT_S390_COMPOSITE_PRIORITY, 511 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | 512 CRYPTO_ALG_NEED_FALLBACK, 513 .cra_blocksize = AES_BLOCK_SIZE, 514 .cra_ctxsize = sizeof(struct s390_aes_ctx), 515 .cra_type = &crypto_blkcipher_type, 516 .cra_module = THIS_MODULE, 517 .cra_init = fallback_init_blk, 518 .cra_exit = fallback_exit_blk, 519 .cra_u = { 520 .blkcipher = { 521 .min_keysize = AES_MIN_KEY_SIZE, 522 .max_keysize = AES_MAX_KEY_SIZE, 523 .ivsize = AES_BLOCK_SIZE, 524 .setkey = cbc_aes_set_key, 525 .encrypt = cbc_aes_encrypt, 526 .decrypt = cbc_aes_decrypt, 527 } 528 } 529 }; 530 531 static int xts_fallback_setkey(struct crypto_tfm *tfm, const u8 *key, 532 unsigned int len) 533 { 534 struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm); 535 unsigned int ret; 536 537 xts_ctx->fallback->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; 538 xts_ctx->fallback->base.crt_flags |= (tfm->crt_flags & 539 CRYPTO_TFM_REQ_MASK); 540 541 ret = crypto_blkcipher_setkey(xts_ctx->fallback, key, len); 542 if (ret) { 543 tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK; 544 tfm->crt_flags |= (xts_ctx->fallback->base.crt_flags & 545 CRYPTO_TFM_RES_MASK); 546 } 547 return ret; 548 } 549 550 static int xts_fallback_decrypt(struct blkcipher_desc *desc, 551 struct scatterlist *dst, struct scatterlist *src, 552 unsigned int nbytes) 553 { 554 struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm); 555 struct crypto_blkcipher *tfm; 556 unsigned int ret; 557 558 tfm = desc->tfm; 559 desc->tfm = xts_ctx->fallback; 560 561 ret = crypto_blkcipher_decrypt_iv(desc, dst, src, nbytes); 562 563 desc->tfm = tfm; 564 return ret; 565 } 566 567 static int xts_fallback_encrypt(struct blkcipher_desc *desc, 568 struct scatterlist *dst, struct scatterlist *src, 569 unsigned int nbytes) 570 { 571 struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm); 572 struct crypto_blkcipher *tfm; 573 unsigned int ret; 574 575 tfm = desc->tfm; 576 desc->tfm = xts_ctx->fallback; 577 578 ret = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes); 579 580 desc->tfm = tfm; 581 return ret; 582 } 583 584 static int xts_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, 585 unsigned int key_len) 586 { 587 struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm); 588 u32 *flags = &tfm->crt_flags; 589 590 switch (key_len) { 591 case 32: 592 xts_ctx->enc = KM_XTS_128_ENCRYPT; 593 xts_ctx->dec = KM_XTS_128_DECRYPT; 594 memcpy(xts_ctx->key + 16, in_key, 16); 595 memcpy(xts_ctx->pcc_key + 16, in_key + 16, 16); 596 break; 597 case 48: 598 xts_ctx->enc = 0; 599 xts_ctx->dec = 0; 600 xts_fallback_setkey(tfm, in_key, key_len); 601 break; 602 case 64: 603 xts_ctx->enc = KM_XTS_256_ENCRYPT; 604 xts_ctx->dec = KM_XTS_256_DECRYPT; 605 memcpy(xts_ctx->key, in_key, 32); 606 memcpy(xts_ctx->pcc_key, in_key + 32, 32); 607 break; 608 default: 609 *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; 610 return -EINVAL; 611 } 612 xts_ctx->key_len = key_len; 613 return 0; 614 } 615 616 static int xts_aes_crypt(struct blkcipher_desc *desc, long func, 617 struct s390_xts_ctx *xts_ctx, 618 struct blkcipher_walk *walk) 619 { 620 unsigned int offset = (xts_ctx->key_len >> 1) & 0x10; 621 int ret = blkcipher_walk_virt(desc, walk); 622 unsigned int nbytes = walk->nbytes; 623 unsigned int n; 624 u8 *in, *out; 625 struct pcc_param pcc_param; 626 struct { 627 u8 key[32]; 628 u8 init[16]; 629 } xts_param; 630 631 if (!nbytes) 632 goto out; 633 634 memset(pcc_param.block, 0, sizeof(pcc_param.block)); 635 memset(pcc_param.bit, 0, sizeof(pcc_param.bit)); 636 memset(pcc_param.xts, 0, sizeof(pcc_param.xts)); 637 memcpy(pcc_param.tweak, walk->iv, sizeof(pcc_param.tweak)); 638 memcpy(pcc_param.key, xts_ctx->pcc_key, 32); 639 ret = crypt_s390_pcc(func, &pcc_param.key[offset]); 640 if (ret < 0) 641 return -EIO; 642 643 memcpy(xts_param.key, xts_ctx->key, 32); 644 memcpy(xts_param.init, pcc_param.xts, 16); 645 do { 646 /* only use complete blocks */ 647 n = nbytes & ~(AES_BLOCK_SIZE - 1); 648 out = walk->dst.virt.addr; 649 in = walk->src.virt.addr; 650 651 ret = crypt_s390_km(func, &xts_param.key[offset], out, in, n); 652 if (ret < 0 || ret != n) 653 return -EIO; 654 655 nbytes &= AES_BLOCK_SIZE - 1; 656 ret = blkcipher_walk_done(desc, walk, nbytes); 657 } while ((nbytes = walk->nbytes)); 658 out: 659 return ret; 660 } 661 662 static int xts_aes_encrypt(struct blkcipher_desc *desc, 663 struct scatterlist *dst, struct scatterlist *src, 664 unsigned int nbytes) 665 { 666 struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm); 667 struct blkcipher_walk walk; 668 669 if (unlikely(xts_ctx->key_len == 48)) 670 return xts_fallback_encrypt(desc, dst, src, nbytes); 671 672 blkcipher_walk_init(&walk, dst, src, nbytes); 673 return xts_aes_crypt(desc, xts_ctx->enc, xts_ctx, &walk); 674 } 675 676 static int xts_aes_decrypt(struct blkcipher_desc *desc, 677 struct scatterlist *dst, struct scatterlist *src, 678 unsigned int nbytes) 679 { 680 struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm); 681 struct blkcipher_walk walk; 682 683 if (unlikely(xts_ctx->key_len == 48)) 684 return xts_fallback_decrypt(desc, dst, src, nbytes); 685 686 blkcipher_walk_init(&walk, dst, src, nbytes); 687 return xts_aes_crypt(desc, xts_ctx->dec, xts_ctx, &walk); 688 } 689 690 static int xts_fallback_init(struct crypto_tfm *tfm) 691 { 692 const char *name = tfm->__crt_alg->cra_name; 693 struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm); 694 695 xts_ctx->fallback = crypto_alloc_blkcipher(name, 0, 696 CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK); 697 698 if (IS_ERR(xts_ctx->fallback)) { 699 pr_err("Allocating XTS fallback algorithm %s failed\n", 700 name); 701 return PTR_ERR(xts_ctx->fallback); 702 } 703 return 0; 704 } 705 706 static void xts_fallback_exit(struct crypto_tfm *tfm) 707 { 708 struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm); 709 710 crypto_free_blkcipher(xts_ctx->fallback); 711 xts_ctx->fallback = NULL; 712 } 713 714 static struct crypto_alg xts_aes_alg = { 715 .cra_name = "xts(aes)", 716 .cra_driver_name = "xts-aes-s390", 717 .cra_priority = CRYPT_S390_COMPOSITE_PRIORITY, 718 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | 719 CRYPTO_ALG_NEED_FALLBACK, 720 .cra_blocksize = AES_BLOCK_SIZE, 721 .cra_ctxsize = sizeof(struct s390_xts_ctx), 722 .cra_type = &crypto_blkcipher_type, 723 .cra_module = THIS_MODULE, 724 .cra_init = xts_fallback_init, 725 .cra_exit = xts_fallback_exit, 726 .cra_u = { 727 .blkcipher = { 728 .min_keysize = 2 * AES_MIN_KEY_SIZE, 729 .max_keysize = 2 * AES_MAX_KEY_SIZE, 730 .ivsize = AES_BLOCK_SIZE, 731 .setkey = xts_aes_set_key, 732 .encrypt = xts_aes_encrypt, 733 .decrypt = xts_aes_decrypt, 734 } 735 } 736 }; 737 738 static int xts_aes_alg_reg; 739 740 static int ctr_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, 741 unsigned int key_len) 742 { 743 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 744 745 switch (key_len) { 746 case 16: 747 sctx->enc = KMCTR_AES_128_ENCRYPT; 748 sctx->dec = KMCTR_AES_128_DECRYPT; 749 break; 750 case 24: 751 sctx->enc = KMCTR_AES_192_ENCRYPT; 752 sctx->dec = KMCTR_AES_192_DECRYPT; 753 break; 754 case 32: 755 sctx->enc = KMCTR_AES_256_ENCRYPT; 756 sctx->dec = KMCTR_AES_256_DECRYPT; 757 break; 758 } 759 760 return aes_set_key(tfm, in_key, key_len); 761 } 762 763 static unsigned int __ctrblk_init(u8 *ctrptr, unsigned int nbytes) 764 { 765 unsigned int i, n; 766 767 /* only use complete blocks, max. PAGE_SIZE */ 768 n = (nbytes > PAGE_SIZE) ? PAGE_SIZE : nbytes & ~(AES_BLOCK_SIZE - 1); 769 for (i = AES_BLOCK_SIZE; i < n; i += AES_BLOCK_SIZE) { 770 memcpy(ctrptr + i, ctrptr + i - AES_BLOCK_SIZE, 771 AES_BLOCK_SIZE); 772 crypto_inc(ctrptr + i, AES_BLOCK_SIZE); 773 } 774 return n; 775 } 776 777 static int ctr_aes_crypt(struct blkcipher_desc *desc, long func, 778 struct s390_aes_ctx *sctx, struct blkcipher_walk *walk) 779 { 780 int ret = blkcipher_walk_virt_block(desc, walk, AES_BLOCK_SIZE); 781 unsigned int n, nbytes; 782 u8 buf[AES_BLOCK_SIZE], ctrbuf[AES_BLOCK_SIZE]; 783 u8 *out, *in, *ctrptr = ctrbuf; 784 785 if (!walk->nbytes) 786 return ret; 787 788 if (spin_trylock(&ctrblk_lock)) 789 ctrptr = ctrblk; 790 791 memcpy(ctrptr, walk->iv, AES_BLOCK_SIZE); 792 while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) { 793 out = walk->dst.virt.addr; 794 in = walk->src.virt.addr; 795 while (nbytes >= AES_BLOCK_SIZE) { 796 if (ctrptr == ctrblk) 797 n = __ctrblk_init(ctrptr, nbytes); 798 else 799 n = AES_BLOCK_SIZE; 800 ret = crypt_s390_kmctr(func, sctx->key, out, in, 801 n, ctrptr); 802 if (ret < 0 || ret != n) { 803 if (ctrptr == ctrblk) 804 spin_unlock(&ctrblk_lock); 805 return -EIO; 806 } 807 if (n > AES_BLOCK_SIZE) 808 memcpy(ctrptr, ctrptr + n - AES_BLOCK_SIZE, 809 AES_BLOCK_SIZE); 810 crypto_inc(ctrptr, AES_BLOCK_SIZE); 811 out += n; 812 in += n; 813 nbytes -= n; 814 } 815 ret = blkcipher_walk_done(desc, walk, nbytes); 816 } 817 if (ctrptr == ctrblk) { 818 if (nbytes) 819 memcpy(ctrbuf, ctrptr, AES_BLOCK_SIZE); 820 else 821 memcpy(walk->iv, ctrptr, AES_BLOCK_SIZE); 822 spin_unlock(&ctrblk_lock); 823 } else { 824 if (!nbytes) 825 memcpy(walk->iv, ctrptr, AES_BLOCK_SIZE); 826 } 827 /* 828 * final block may be < AES_BLOCK_SIZE, copy only nbytes 829 */ 830 if (nbytes) { 831 out = walk->dst.virt.addr; 832 in = walk->src.virt.addr; 833 ret = crypt_s390_kmctr(func, sctx->key, buf, in, 834 AES_BLOCK_SIZE, ctrbuf); 835 if (ret < 0 || ret != AES_BLOCK_SIZE) 836 return -EIO; 837 memcpy(out, buf, nbytes); 838 crypto_inc(ctrbuf, AES_BLOCK_SIZE); 839 ret = blkcipher_walk_done(desc, walk, 0); 840 memcpy(walk->iv, ctrbuf, AES_BLOCK_SIZE); 841 } 842 843 return ret; 844 } 845 846 static int ctr_aes_encrypt(struct blkcipher_desc *desc, 847 struct scatterlist *dst, struct scatterlist *src, 848 unsigned int nbytes) 849 { 850 struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); 851 struct blkcipher_walk walk; 852 853 blkcipher_walk_init(&walk, dst, src, nbytes); 854 return ctr_aes_crypt(desc, sctx->enc, sctx, &walk); 855 } 856 857 static int ctr_aes_decrypt(struct blkcipher_desc *desc, 858 struct scatterlist *dst, struct scatterlist *src, 859 unsigned int nbytes) 860 { 861 struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); 862 struct blkcipher_walk walk; 863 864 blkcipher_walk_init(&walk, dst, src, nbytes); 865 return ctr_aes_crypt(desc, sctx->dec, sctx, &walk); 866 } 867 868 static struct crypto_alg ctr_aes_alg = { 869 .cra_name = "ctr(aes)", 870 .cra_driver_name = "ctr-aes-s390", 871 .cra_priority = CRYPT_S390_COMPOSITE_PRIORITY, 872 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, 873 .cra_blocksize = 1, 874 .cra_ctxsize = sizeof(struct s390_aes_ctx), 875 .cra_type = &crypto_blkcipher_type, 876 .cra_module = THIS_MODULE, 877 .cra_u = { 878 .blkcipher = { 879 .min_keysize = AES_MIN_KEY_SIZE, 880 .max_keysize = AES_MAX_KEY_SIZE, 881 .ivsize = AES_BLOCK_SIZE, 882 .setkey = ctr_aes_set_key, 883 .encrypt = ctr_aes_encrypt, 884 .decrypt = ctr_aes_decrypt, 885 } 886 } 887 }; 888 889 static int ctr_aes_alg_reg; 890 891 static int __init aes_s390_init(void) 892 { 893 int ret; 894 895 if (crypt_s390_func_available(KM_AES_128_ENCRYPT, CRYPT_S390_MSA)) 896 keylen_flag |= AES_KEYLEN_128; 897 if (crypt_s390_func_available(KM_AES_192_ENCRYPT, CRYPT_S390_MSA)) 898 keylen_flag |= AES_KEYLEN_192; 899 if (crypt_s390_func_available(KM_AES_256_ENCRYPT, CRYPT_S390_MSA)) 900 keylen_flag |= AES_KEYLEN_256; 901 902 if (!keylen_flag) 903 return -EOPNOTSUPP; 904 905 /* z9 109 and z9 BC/EC only support 128 bit key length */ 906 if (keylen_flag == AES_KEYLEN_128) 907 pr_info("AES hardware acceleration is only available for" 908 " 128-bit keys\n"); 909 910 ret = crypto_register_alg(&aes_alg); 911 if (ret) 912 goto aes_err; 913 914 ret = crypto_register_alg(&ecb_aes_alg); 915 if (ret) 916 goto ecb_aes_err; 917 918 ret = crypto_register_alg(&cbc_aes_alg); 919 if (ret) 920 goto cbc_aes_err; 921 922 if (crypt_s390_func_available(KM_XTS_128_ENCRYPT, 923 CRYPT_S390_MSA | CRYPT_S390_MSA4) && 924 crypt_s390_func_available(KM_XTS_256_ENCRYPT, 925 CRYPT_S390_MSA | CRYPT_S390_MSA4)) { 926 ret = crypto_register_alg(&xts_aes_alg); 927 if (ret) 928 goto xts_aes_err; 929 xts_aes_alg_reg = 1; 930 } 931 932 if (crypt_s390_func_available(KMCTR_AES_128_ENCRYPT, 933 CRYPT_S390_MSA | CRYPT_S390_MSA4) && 934 crypt_s390_func_available(KMCTR_AES_192_ENCRYPT, 935 CRYPT_S390_MSA | CRYPT_S390_MSA4) && 936 crypt_s390_func_available(KMCTR_AES_256_ENCRYPT, 937 CRYPT_S390_MSA | CRYPT_S390_MSA4)) { 938 ctrblk = (u8 *) __get_free_page(GFP_KERNEL); 939 if (!ctrblk) { 940 ret = -ENOMEM; 941 goto ctr_aes_err; 942 } 943 ret = crypto_register_alg(&ctr_aes_alg); 944 if (ret) { 945 free_page((unsigned long) ctrblk); 946 goto ctr_aes_err; 947 } 948 ctr_aes_alg_reg = 1; 949 } 950 951 out: 952 return ret; 953 954 ctr_aes_err: 955 crypto_unregister_alg(&xts_aes_alg); 956 xts_aes_err: 957 crypto_unregister_alg(&cbc_aes_alg); 958 cbc_aes_err: 959 crypto_unregister_alg(&ecb_aes_alg); 960 ecb_aes_err: 961 crypto_unregister_alg(&aes_alg); 962 aes_err: 963 goto out; 964 } 965 966 static void __exit aes_s390_fini(void) 967 { 968 if (ctr_aes_alg_reg) { 969 crypto_unregister_alg(&ctr_aes_alg); 970 free_page((unsigned long) ctrblk); 971 } 972 if (xts_aes_alg_reg) 973 crypto_unregister_alg(&xts_aes_alg); 974 crypto_unregister_alg(&cbc_aes_alg); 975 crypto_unregister_alg(&ecb_aes_alg); 976 crypto_unregister_alg(&aes_alg); 977 } 978 979 module_init(aes_s390_init); 980 module_exit(aes_s390_fini); 981 982 MODULE_ALIAS_CRYPTO("aes-all"); 983 984 MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm"); 985 MODULE_LICENSE("GPL"); 986