1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Cryptographic API. 4 * 5 * s390 implementation of the AES Cipher Algorithm. 6 * 7 * s390 Version: 8 * Copyright IBM Corp. 2005, 2017 9 * Author(s): Jan Glauber (jang@de.ibm.com) 10 * Sebastian Siewior (sebastian@breakpoint.cc> SW-Fallback 11 * Patrick Steuer <patrick.steuer@de.ibm.com> 12 * Harald Freudenberger <freude@de.ibm.com> 13 * 14 * Derived from "crypto/aes_generic.c" 15 */ 16 17 #define KMSG_COMPONENT "aes_s390" 18 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 19 20 #include <crypto/aes.h> 21 #include <crypto/algapi.h> 22 #include <crypto/ghash.h> 23 #include <crypto/internal/aead.h> 24 #include <crypto/internal/skcipher.h> 25 #include <crypto/scatterwalk.h> 26 #include <linux/err.h> 27 #include <linux/module.h> 28 #include <linux/cpufeature.h> 29 #include <linux/init.h> 30 #include <linux/mutex.h> 31 #include <linux/fips.h> 32 #include <linux/string.h> 33 #include <crypto/xts.h> 34 #include <asm/cpacf.h> 35 36 static u8 *ctrblk; 37 static DEFINE_MUTEX(ctrblk_lock); 38 39 static cpacf_mask_t km_functions, kmc_functions, kmctr_functions, 40 kma_functions; 41 42 struct s390_aes_ctx { 43 u8 key[AES_MAX_KEY_SIZE]; 44 int key_len; 45 unsigned long fc; 46 union { 47 struct crypto_skcipher *skcipher; 48 struct crypto_cipher *cip; 49 } fallback; 50 }; 51 52 struct s390_xts_ctx { 53 u8 key[32]; 54 u8 pcc_key[32]; 55 int key_len; 56 unsigned long fc; 57 struct crypto_skcipher *fallback; 58 }; 59 60 struct gcm_sg_walk { 61 struct scatter_walk walk; 62 unsigned int walk_bytes; 63 u8 *walk_ptr; 64 unsigned int walk_bytes_remain; 65 u8 buf[AES_BLOCK_SIZE]; 66 unsigned int buf_bytes; 67 u8 *ptr; 68 unsigned int nbytes; 69 }; 70 71 static int setkey_fallback_cip(struct crypto_tfm *tfm, const u8 *in_key, 72 unsigned int key_len) 73 { 74 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 75 int ret; 76 77 sctx->fallback.cip->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; 78 sctx->fallback.cip->base.crt_flags |= (tfm->crt_flags & 79 CRYPTO_TFM_REQ_MASK); 80 81 ret = crypto_cipher_setkey(sctx->fallback.cip, in_key, key_len); 82 if (ret) { 83 tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK; 84 tfm->crt_flags |= (sctx->fallback.cip->base.crt_flags & 85 CRYPTO_TFM_RES_MASK); 86 } 87 return ret; 88 } 89 90 static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, 91 unsigned int key_len) 92 { 93 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 94 unsigned long fc; 95 96 /* Pick the correct function code based on the key length */ 97 fc = (key_len == 16) ? CPACF_KM_AES_128 : 98 (key_len == 24) ? CPACF_KM_AES_192 : 99 (key_len == 32) ? CPACF_KM_AES_256 : 0; 100 101 /* Check if the function code is available */ 102 sctx->fc = (fc && cpacf_test_func(&km_functions, fc)) ? fc : 0; 103 if (!sctx->fc) 104 return setkey_fallback_cip(tfm, in_key, key_len); 105 106 sctx->key_len = key_len; 107 memcpy(sctx->key, in_key, key_len); 108 return 0; 109 } 110 111 static void crypto_aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) 112 { 113 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 114 115 if (unlikely(!sctx->fc)) { 116 crypto_cipher_encrypt_one(sctx->fallback.cip, out, in); 117 return; 118 } 119 cpacf_km(sctx->fc, &sctx->key, out, in, AES_BLOCK_SIZE); 120 } 121 122 static void crypto_aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) 123 { 124 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 125 126 if (unlikely(!sctx->fc)) { 127 crypto_cipher_decrypt_one(sctx->fallback.cip, out, in); 128 return; 129 } 130 cpacf_km(sctx->fc | CPACF_DECRYPT, 131 &sctx->key, out, in, AES_BLOCK_SIZE); 132 } 133 134 static int fallback_init_cip(struct crypto_tfm *tfm) 135 { 136 const char *name = tfm->__crt_alg->cra_name; 137 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 138 139 sctx->fallback.cip = crypto_alloc_cipher(name, 0, 140 CRYPTO_ALG_NEED_FALLBACK); 141 142 if (IS_ERR(sctx->fallback.cip)) { 143 pr_err("Allocating AES fallback algorithm %s failed\n", 144 name); 145 return PTR_ERR(sctx->fallback.cip); 146 } 147 148 return 0; 149 } 150 151 static void fallback_exit_cip(struct crypto_tfm *tfm) 152 { 153 struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); 154 155 crypto_free_cipher(sctx->fallback.cip); 156 sctx->fallback.cip = NULL; 157 } 158 159 static struct crypto_alg aes_alg = { 160 .cra_name = "aes", 161 .cra_driver_name = "aes-s390", 162 .cra_priority = 300, 163 .cra_flags = CRYPTO_ALG_TYPE_CIPHER | 164 CRYPTO_ALG_NEED_FALLBACK, 165 .cra_blocksize = AES_BLOCK_SIZE, 166 .cra_ctxsize = sizeof(struct s390_aes_ctx), 167 .cra_module = THIS_MODULE, 168 .cra_init = fallback_init_cip, 169 .cra_exit = fallback_exit_cip, 170 .cra_u = { 171 .cipher = { 172 .cia_min_keysize = AES_MIN_KEY_SIZE, 173 .cia_max_keysize = AES_MAX_KEY_SIZE, 174 .cia_setkey = aes_set_key, 175 .cia_encrypt = crypto_aes_encrypt, 176 .cia_decrypt = crypto_aes_decrypt, 177 } 178 } 179 }; 180 181 static int setkey_fallback_skcipher(struct crypto_skcipher *tfm, const u8 *key, 182 unsigned int len) 183 { 184 struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm); 185 int ret; 186 187 crypto_skcipher_clear_flags(sctx->fallback.skcipher, 188 CRYPTO_TFM_REQ_MASK); 189 crypto_skcipher_set_flags(sctx->fallback.skcipher, 190 crypto_skcipher_get_flags(tfm) & 191 CRYPTO_TFM_REQ_MASK); 192 ret = crypto_skcipher_setkey(sctx->fallback.skcipher, key, len); 193 crypto_skcipher_set_flags(tfm, 194 crypto_skcipher_get_flags(sctx->fallback.skcipher) & 195 CRYPTO_TFM_RES_MASK); 196 return ret; 197 } 198 199 static int fallback_skcipher_crypt(struct s390_aes_ctx *sctx, 200 struct skcipher_request *req, 201 unsigned long modifier) 202 { 203 struct skcipher_request *subreq = skcipher_request_ctx(req); 204 205 *subreq = *req; 206 skcipher_request_set_tfm(subreq, sctx->fallback.skcipher); 207 return (modifier & CPACF_DECRYPT) ? 208 crypto_skcipher_decrypt(subreq) : 209 crypto_skcipher_encrypt(subreq); 210 } 211 212 static int ecb_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key, 213 unsigned int key_len) 214 { 215 struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm); 216 unsigned long fc; 217 218 /* Pick the correct function code based on the key length */ 219 fc = (key_len == 16) ? CPACF_KM_AES_128 : 220 (key_len == 24) ? CPACF_KM_AES_192 : 221 (key_len == 32) ? CPACF_KM_AES_256 : 0; 222 223 /* Check if the function code is available */ 224 sctx->fc = (fc && cpacf_test_func(&km_functions, fc)) ? fc : 0; 225 if (!sctx->fc) 226 return setkey_fallback_skcipher(tfm, in_key, key_len); 227 228 sctx->key_len = key_len; 229 memcpy(sctx->key, in_key, key_len); 230 return 0; 231 } 232 233 static int ecb_aes_crypt(struct skcipher_request *req, unsigned long modifier) 234 { 235 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 236 struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm); 237 struct skcipher_walk walk; 238 unsigned int nbytes, n; 239 int ret; 240 241 if (unlikely(!sctx->fc)) 242 return fallback_skcipher_crypt(sctx, req, modifier); 243 244 ret = skcipher_walk_virt(&walk, req, false); 245 while ((nbytes = walk.nbytes) != 0) { 246 /* only use complete blocks */ 247 n = nbytes & ~(AES_BLOCK_SIZE - 1); 248 cpacf_km(sctx->fc | modifier, sctx->key, 249 walk.dst.virt.addr, walk.src.virt.addr, n); 250 ret = skcipher_walk_done(&walk, nbytes - n); 251 } 252 return ret; 253 } 254 255 static int ecb_aes_encrypt(struct skcipher_request *req) 256 { 257 return ecb_aes_crypt(req, 0); 258 } 259 260 static int ecb_aes_decrypt(struct skcipher_request *req) 261 { 262 return ecb_aes_crypt(req, CPACF_DECRYPT); 263 } 264 265 static int fallback_init_skcipher(struct crypto_skcipher *tfm) 266 { 267 const char *name = crypto_tfm_alg_name(&tfm->base); 268 struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm); 269 270 sctx->fallback.skcipher = crypto_alloc_skcipher(name, 0, 271 CRYPTO_ALG_NEED_FALLBACK | CRYPTO_ALG_ASYNC); 272 273 if (IS_ERR(sctx->fallback.skcipher)) { 274 pr_err("Allocating AES fallback algorithm %s failed\n", 275 name); 276 return PTR_ERR(sctx->fallback.skcipher); 277 } 278 279 crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) + 280 crypto_skcipher_reqsize(sctx->fallback.skcipher)); 281 return 0; 282 } 283 284 static void fallback_exit_skcipher(struct crypto_skcipher *tfm) 285 { 286 struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm); 287 288 crypto_free_skcipher(sctx->fallback.skcipher); 289 } 290 291 static struct skcipher_alg ecb_aes_alg = { 292 .base.cra_name = "ecb(aes)", 293 .base.cra_driver_name = "ecb-aes-s390", 294 .base.cra_priority = 401, /* combo: aes + ecb + 1 */ 295 .base.cra_flags = CRYPTO_ALG_NEED_FALLBACK, 296 .base.cra_blocksize = AES_BLOCK_SIZE, 297 .base.cra_ctxsize = sizeof(struct s390_aes_ctx), 298 .base.cra_module = THIS_MODULE, 299 .init = fallback_init_skcipher, 300 .exit = fallback_exit_skcipher, 301 .min_keysize = AES_MIN_KEY_SIZE, 302 .max_keysize = AES_MAX_KEY_SIZE, 303 .setkey = ecb_aes_set_key, 304 .encrypt = ecb_aes_encrypt, 305 .decrypt = ecb_aes_decrypt, 306 }; 307 308 static int cbc_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key, 309 unsigned int key_len) 310 { 311 struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm); 312 unsigned long fc; 313 314 /* Pick the correct function code based on the key length */ 315 fc = (key_len == 16) ? CPACF_KMC_AES_128 : 316 (key_len == 24) ? CPACF_KMC_AES_192 : 317 (key_len == 32) ? CPACF_KMC_AES_256 : 0; 318 319 /* Check if the function code is available */ 320 sctx->fc = (fc && cpacf_test_func(&kmc_functions, fc)) ? fc : 0; 321 if (!sctx->fc) 322 return setkey_fallback_skcipher(tfm, in_key, key_len); 323 324 sctx->key_len = key_len; 325 memcpy(sctx->key, in_key, key_len); 326 return 0; 327 } 328 329 static int cbc_aes_crypt(struct skcipher_request *req, unsigned long modifier) 330 { 331 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 332 struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm); 333 struct skcipher_walk walk; 334 unsigned int nbytes, n; 335 int ret; 336 struct { 337 u8 iv[AES_BLOCK_SIZE]; 338 u8 key[AES_MAX_KEY_SIZE]; 339 } param; 340 341 if (unlikely(!sctx->fc)) 342 return fallback_skcipher_crypt(sctx, req, modifier); 343 344 ret = skcipher_walk_virt(&walk, req, false); 345 if (ret) 346 return ret; 347 memcpy(param.iv, walk.iv, AES_BLOCK_SIZE); 348 memcpy(param.key, sctx->key, sctx->key_len); 349 while ((nbytes = walk.nbytes) != 0) { 350 /* only use complete blocks */ 351 n = nbytes & ~(AES_BLOCK_SIZE - 1); 352 cpacf_kmc(sctx->fc | modifier, ¶m, 353 walk.dst.virt.addr, walk.src.virt.addr, n); 354 memcpy(walk.iv, param.iv, AES_BLOCK_SIZE); 355 ret = skcipher_walk_done(&walk, nbytes - n); 356 } 357 return ret; 358 } 359 360 static int cbc_aes_encrypt(struct skcipher_request *req) 361 { 362 return cbc_aes_crypt(req, 0); 363 } 364 365 static int cbc_aes_decrypt(struct skcipher_request *req) 366 { 367 return cbc_aes_crypt(req, CPACF_DECRYPT); 368 } 369 370 static struct skcipher_alg cbc_aes_alg = { 371 .base.cra_name = "cbc(aes)", 372 .base.cra_driver_name = "cbc-aes-s390", 373 .base.cra_priority = 402, /* ecb-aes-s390 + 1 */ 374 .base.cra_flags = CRYPTO_ALG_NEED_FALLBACK, 375 .base.cra_blocksize = AES_BLOCK_SIZE, 376 .base.cra_ctxsize = sizeof(struct s390_aes_ctx), 377 .base.cra_module = THIS_MODULE, 378 .init = fallback_init_skcipher, 379 .exit = fallback_exit_skcipher, 380 .min_keysize = AES_MIN_KEY_SIZE, 381 .max_keysize = AES_MAX_KEY_SIZE, 382 .ivsize = AES_BLOCK_SIZE, 383 .setkey = cbc_aes_set_key, 384 .encrypt = cbc_aes_encrypt, 385 .decrypt = cbc_aes_decrypt, 386 }; 387 388 static int xts_fallback_setkey(struct crypto_skcipher *tfm, const u8 *key, 389 unsigned int len) 390 { 391 struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm); 392 int ret; 393 394 crypto_skcipher_clear_flags(xts_ctx->fallback, CRYPTO_TFM_REQ_MASK); 395 crypto_skcipher_set_flags(xts_ctx->fallback, 396 crypto_skcipher_get_flags(tfm) & 397 CRYPTO_TFM_REQ_MASK); 398 ret = crypto_skcipher_setkey(xts_ctx->fallback, key, len); 399 crypto_skcipher_set_flags(tfm, 400 crypto_skcipher_get_flags(xts_ctx->fallback) & 401 CRYPTO_TFM_RES_MASK); 402 return ret; 403 } 404 405 static int xts_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key, 406 unsigned int key_len) 407 { 408 struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm); 409 unsigned long fc; 410 int err; 411 412 err = xts_fallback_setkey(tfm, in_key, key_len); 413 if (err) 414 return err; 415 416 /* In fips mode only 128 bit or 256 bit keys are valid */ 417 if (fips_enabled && key_len != 32 && key_len != 64) { 418 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); 419 return -EINVAL; 420 } 421 422 /* Pick the correct function code based on the key length */ 423 fc = (key_len == 32) ? CPACF_KM_XTS_128 : 424 (key_len == 64) ? CPACF_KM_XTS_256 : 0; 425 426 /* Check if the function code is available */ 427 xts_ctx->fc = (fc && cpacf_test_func(&km_functions, fc)) ? fc : 0; 428 if (!xts_ctx->fc) 429 return 0; 430 431 /* Split the XTS key into the two subkeys */ 432 key_len = key_len / 2; 433 xts_ctx->key_len = key_len; 434 memcpy(xts_ctx->key, in_key, key_len); 435 memcpy(xts_ctx->pcc_key, in_key + key_len, key_len); 436 return 0; 437 } 438 439 static int xts_aes_crypt(struct skcipher_request *req, unsigned long modifier) 440 { 441 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 442 struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm); 443 struct skcipher_walk walk; 444 unsigned int offset, nbytes, n; 445 int ret; 446 struct { 447 u8 key[32]; 448 u8 tweak[16]; 449 u8 block[16]; 450 u8 bit[16]; 451 u8 xts[16]; 452 } pcc_param; 453 struct { 454 u8 key[32]; 455 u8 init[16]; 456 } xts_param; 457 458 if (req->cryptlen < AES_BLOCK_SIZE) 459 return -EINVAL; 460 461 if (unlikely(!xts_ctx->fc || (req->cryptlen % AES_BLOCK_SIZE) != 0)) { 462 struct skcipher_request *subreq = skcipher_request_ctx(req); 463 464 *subreq = *req; 465 skcipher_request_set_tfm(subreq, xts_ctx->fallback); 466 return (modifier & CPACF_DECRYPT) ? 467 crypto_skcipher_decrypt(subreq) : 468 crypto_skcipher_encrypt(subreq); 469 } 470 471 ret = skcipher_walk_virt(&walk, req, false); 472 if (ret) 473 return ret; 474 offset = xts_ctx->key_len & 0x10; 475 memset(pcc_param.block, 0, sizeof(pcc_param.block)); 476 memset(pcc_param.bit, 0, sizeof(pcc_param.bit)); 477 memset(pcc_param.xts, 0, sizeof(pcc_param.xts)); 478 memcpy(pcc_param.tweak, walk.iv, sizeof(pcc_param.tweak)); 479 memcpy(pcc_param.key + offset, xts_ctx->pcc_key, xts_ctx->key_len); 480 cpacf_pcc(xts_ctx->fc, pcc_param.key + offset); 481 482 memcpy(xts_param.key + offset, xts_ctx->key, xts_ctx->key_len); 483 memcpy(xts_param.init, pcc_param.xts, 16); 484 485 while ((nbytes = walk.nbytes) != 0) { 486 /* only use complete blocks */ 487 n = nbytes & ~(AES_BLOCK_SIZE - 1); 488 cpacf_km(xts_ctx->fc | modifier, xts_param.key + offset, 489 walk.dst.virt.addr, walk.src.virt.addr, n); 490 ret = skcipher_walk_done(&walk, nbytes - n); 491 } 492 return ret; 493 } 494 495 static int xts_aes_encrypt(struct skcipher_request *req) 496 { 497 return xts_aes_crypt(req, 0); 498 } 499 500 static int xts_aes_decrypt(struct skcipher_request *req) 501 { 502 return xts_aes_crypt(req, CPACF_DECRYPT); 503 } 504 505 static int xts_fallback_init(struct crypto_skcipher *tfm) 506 { 507 const char *name = crypto_tfm_alg_name(&tfm->base); 508 struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm); 509 510 xts_ctx->fallback = crypto_alloc_skcipher(name, 0, 511 CRYPTO_ALG_NEED_FALLBACK | CRYPTO_ALG_ASYNC); 512 513 if (IS_ERR(xts_ctx->fallback)) { 514 pr_err("Allocating XTS fallback algorithm %s failed\n", 515 name); 516 return PTR_ERR(xts_ctx->fallback); 517 } 518 crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) + 519 crypto_skcipher_reqsize(xts_ctx->fallback)); 520 return 0; 521 } 522 523 static void xts_fallback_exit(struct crypto_skcipher *tfm) 524 { 525 struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm); 526 527 crypto_free_skcipher(xts_ctx->fallback); 528 } 529 530 static struct skcipher_alg xts_aes_alg = { 531 .base.cra_name = "xts(aes)", 532 .base.cra_driver_name = "xts-aes-s390", 533 .base.cra_priority = 402, /* ecb-aes-s390 + 1 */ 534 .base.cra_flags = CRYPTO_ALG_NEED_FALLBACK, 535 .base.cra_blocksize = AES_BLOCK_SIZE, 536 .base.cra_ctxsize = sizeof(struct s390_xts_ctx), 537 .base.cra_module = THIS_MODULE, 538 .init = xts_fallback_init, 539 .exit = xts_fallback_exit, 540 .min_keysize = 2 * AES_MIN_KEY_SIZE, 541 .max_keysize = 2 * AES_MAX_KEY_SIZE, 542 .ivsize = AES_BLOCK_SIZE, 543 .setkey = xts_aes_set_key, 544 .encrypt = xts_aes_encrypt, 545 .decrypt = xts_aes_decrypt, 546 }; 547 548 static int ctr_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key, 549 unsigned int key_len) 550 { 551 struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm); 552 unsigned long fc; 553 554 /* Pick the correct function code based on the key length */ 555 fc = (key_len == 16) ? CPACF_KMCTR_AES_128 : 556 (key_len == 24) ? CPACF_KMCTR_AES_192 : 557 (key_len == 32) ? CPACF_KMCTR_AES_256 : 0; 558 559 /* Check if the function code is available */ 560 sctx->fc = (fc && cpacf_test_func(&kmctr_functions, fc)) ? fc : 0; 561 if (!sctx->fc) 562 return setkey_fallback_skcipher(tfm, in_key, key_len); 563 564 sctx->key_len = key_len; 565 memcpy(sctx->key, in_key, key_len); 566 return 0; 567 } 568 569 static unsigned int __ctrblk_init(u8 *ctrptr, u8 *iv, unsigned int nbytes) 570 { 571 unsigned int i, n; 572 573 /* only use complete blocks, max. PAGE_SIZE */ 574 memcpy(ctrptr, iv, AES_BLOCK_SIZE); 575 n = (nbytes > PAGE_SIZE) ? PAGE_SIZE : nbytes & ~(AES_BLOCK_SIZE - 1); 576 for (i = (n / AES_BLOCK_SIZE) - 1; i > 0; i--) { 577 memcpy(ctrptr + AES_BLOCK_SIZE, ctrptr, AES_BLOCK_SIZE); 578 crypto_inc(ctrptr + AES_BLOCK_SIZE, AES_BLOCK_SIZE); 579 ctrptr += AES_BLOCK_SIZE; 580 } 581 return n; 582 } 583 584 static int ctr_aes_crypt(struct skcipher_request *req) 585 { 586 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 587 struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm); 588 u8 buf[AES_BLOCK_SIZE], *ctrptr; 589 struct skcipher_walk walk; 590 unsigned int n, nbytes; 591 int ret, locked; 592 593 if (unlikely(!sctx->fc)) 594 return fallback_skcipher_crypt(sctx, req, 0); 595 596 locked = mutex_trylock(&ctrblk_lock); 597 598 ret = skcipher_walk_virt(&walk, req, false); 599 while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) { 600 n = AES_BLOCK_SIZE; 601 602 if (nbytes >= 2*AES_BLOCK_SIZE && locked) 603 n = __ctrblk_init(ctrblk, walk.iv, nbytes); 604 ctrptr = (n > AES_BLOCK_SIZE) ? ctrblk : walk.iv; 605 cpacf_kmctr(sctx->fc, sctx->key, walk.dst.virt.addr, 606 walk.src.virt.addr, n, ctrptr); 607 if (ctrptr == ctrblk) 608 memcpy(walk.iv, ctrptr + n - AES_BLOCK_SIZE, 609 AES_BLOCK_SIZE); 610 crypto_inc(walk.iv, AES_BLOCK_SIZE); 611 ret = skcipher_walk_done(&walk, nbytes - n); 612 } 613 if (locked) 614 mutex_unlock(&ctrblk_lock); 615 /* 616 * final block may be < AES_BLOCK_SIZE, copy only nbytes 617 */ 618 if (nbytes) { 619 cpacf_kmctr(sctx->fc, sctx->key, buf, walk.src.virt.addr, 620 AES_BLOCK_SIZE, walk.iv); 621 memcpy(walk.dst.virt.addr, buf, nbytes); 622 crypto_inc(walk.iv, AES_BLOCK_SIZE); 623 ret = skcipher_walk_done(&walk, 0); 624 } 625 626 return ret; 627 } 628 629 static struct skcipher_alg ctr_aes_alg = { 630 .base.cra_name = "ctr(aes)", 631 .base.cra_driver_name = "ctr-aes-s390", 632 .base.cra_priority = 402, /* ecb-aes-s390 + 1 */ 633 .base.cra_flags = CRYPTO_ALG_NEED_FALLBACK, 634 .base.cra_blocksize = 1, 635 .base.cra_ctxsize = sizeof(struct s390_aes_ctx), 636 .base.cra_module = THIS_MODULE, 637 .init = fallback_init_skcipher, 638 .exit = fallback_exit_skcipher, 639 .min_keysize = AES_MIN_KEY_SIZE, 640 .max_keysize = AES_MAX_KEY_SIZE, 641 .ivsize = AES_BLOCK_SIZE, 642 .setkey = ctr_aes_set_key, 643 .encrypt = ctr_aes_crypt, 644 .decrypt = ctr_aes_crypt, 645 .chunksize = AES_BLOCK_SIZE, 646 }; 647 648 static int gcm_aes_setkey(struct crypto_aead *tfm, const u8 *key, 649 unsigned int keylen) 650 { 651 struct s390_aes_ctx *ctx = crypto_aead_ctx(tfm); 652 653 switch (keylen) { 654 case AES_KEYSIZE_128: 655 ctx->fc = CPACF_KMA_GCM_AES_128; 656 break; 657 case AES_KEYSIZE_192: 658 ctx->fc = CPACF_KMA_GCM_AES_192; 659 break; 660 case AES_KEYSIZE_256: 661 ctx->fc = CPACF_KMA_GCM_AES_256; 662 break; 663 default: 664 return -EINVAL; 665 } 666 667 memcpy(ctx->key, key, keylen); 668 ctx->key_len = keylen; 669 return 0; 670 } 671 672 static int gcm_aes_setauthsize(struct crypto_aead *tfm, unsigned int authsize) 673 { 674 switch (authsize) { 675 case 4: 676 case 8: 677 case 12: 678 case 13: 679 case 14: 680 case 15: 681 case 16: 682 break; 683 default: 684 return -EINVAL; 685 } 686 687 return 0; 688 } 689 690 static void gcm_walk_start(struct gcm_sg_walk *gw, struct scatterlist *sg, 691 unsigned int len) 692 { 693 memset(gw, 0, sizeof(*gw)); 694 gw->walk_bytes_remain = len; 695 scatterwalk_start(&gw->walk, sg); 696 } 697 698 static inline unsigned int _gcm_sg_clamp_and_map(struct gcm_sg_walk *gw) 699 { 700 struct scatterlist *nextsg; 701 702 gw->walk_bytes = scatterwalk_clamp(&gw->walk, gw->walk_bytes_remain); 703 while (!gw->walk_bytes) { 704 nextsg = sg_next(gw->walk.sg); 705 if (!nextsg) 706 return 0; 707 scatterwalk_start(&gw->walk, nextsg); 708 gw->walk_bytes = scatterwalk_clamp(&gw->walk, 709 gw->walk_bytes_remain); 710 } 711 gw->walk_ptr = scatterwalk_map(&gw->walk); 712 return gw->walk_bytes; 713 } 714 715 static inline void _gcm_sg_unmap_and_advance(struct gcm_sg_walk *gw, 716 unsigned int nbytes) 717 { 718 gw->walk_bytes_remain -= nbytes; 719 scatterwalk_unmap(&gw->walk); 720 scatterwalk_advance(&gw->walk, nbytes); 721 scatterwalk_done(&gw->walk, 0, gw->walk_bytes_remain); 722 gw->walk_ptr = NULL; 723 } 724 725 static int gcm_in_walk_go(struct gcm_sg_walk *gw, unsigned int minbytesneeded) 726 { 727 int n; 728 729 if (gw->buf_bytes && gw->buf_bytes >= minbytesneeded) { 730 gw->ptr = gw->buf; 731 gw->nbytes = gw->buf_bytes; 732 goto out; 733 } 734 735 if (gw->walk_bytes_remain == 0) { 736 gw->ptr = NULL; 737 gw->nbytes = 0; 738 goto out; 739 } 740 741 if (!_gcm_sg_clamp_and_map(gw)) { 742 gw->ptr = NULL; 743 gw->nbytes = 0; 744 goto out; 745 } 746 747 if (!gw->buf_bytes && gw->walk_bytes >= minbytesneeded) { 748 gw->ptr = gw->walk_ptr; 749 gw->nbytes = gw->walk_bytes; 750 goto out; 751 } 752 753 while (1) { 754 n = min(gw->walk_bytes, AES_BLOCK_SIZE - gw->buf_bytes); 755 memcpy(gw->buf + gw->buf_bytes, gw->walk_ptr, n); 756 gw->buf_bytes += n; 757 _gcm_sg_unmap_and_advance(gw, n); 758 if (gw->buf_bytes >= minbytesneeded) { 759 gw->ptr = gw->buf; 760 gw->nbytes = gw->buf_bytes; 761 goto out; 762 } 763 if (!_gcm_sg_clamp_and_map(gw)) { 764 gw->ptr = NULL; 765 gw->nbytes = 0; 766 goto out; 767 } 768 } 769 770 out: 771 return gw->nbytes; 772 } 773 774 static int gcm_out_walk_go(struct gcm_sg_walk *gw, unsigned int minbytesneeded) 775 { 776 if (gw->walk_bytes_remain == 0) { 777 gw->ptr = NULL; 778 gw->nbytes = 0; 779 goto out; 780 } 781 782 if (!_gcm_sg_clamp_and_map(gw)) { 783 gw->ptr = NULL; 784 gw->nbytes = 0; 785 goto out; 786 } 787 788 if (gw->walk_bytes >= minbytesneeded) { 789 gw->ptr = gw->walk_ptr; 790 gw->nbytes = gw->walk_bytes; 791 goto out; 792 } 793 794 scatterwalk_unmap(&gw->walk); 795 gw->walk_ptr = NULL; 796 797 gw->ptr = gw->buf; 798 gw->nbytes = sizeof(gw->buf); 799 800 out: 801 return gw->nbytes; 802 } 803 804 static int gcm_in_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone) 805 { 806 if (gw->ptr == NULL) 807 return 0; 808 809 if (gw->ptr == gw->buf) { 810 int n = gw->buf_bytes - bytesdone; 811 if (n > 0) { 812 memmove(gw->buf, gw->buf + bytesdone, n); 813 gw->buf_bytes = n; 814 } else 815 gw->buf_bytes = 0; 816 } else 817 _gcm_sg_unmap_and_advance(gw, bytesdone); 818 819 return bytesdone; 820 } 821 822 static int gcm_out_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone) 823 { 824 int i, n; 825 826 if (gw->ptr == NULL) 827 return 0; 828 829 if (gw->ptr == gw->buf) { 830 for (i = 0; i < bytesdone; i += n) { 831 if (!_gcm_sg_clamp_and_map(gw)) 832 return i; 833 n = min(gw->walk_bytes, bytesdone - i); 834 memcpy(gw->walk_ptr, gw->buf + i, n); 835 _gcm_sg_unmap_and_advance(gw, n); 836 } 837 } else 838 _gcm_sg_unmap_and_advance(gw, bytesdone); 839 840 return bytesdone; 841 } 842 843 static int gcm_aes_crypt(struct aead_request *req, unsigned int flags) 844 { 845 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 846 struct s390_aes_ctx *ctx = crypto_aead_ctx(tfm); 847 unsigned int ivsize = crypto_aead_ivsize(tfm); 848 unsigned int taglen = crypto_aead_authsize(tfm); 849 unsigned int aadlen = req->assoclen; 850 unsigned int pclen = req->cryptlen; 851 int ret = 0; 852 853 unsigned int n, len, in_bytes, out_bytes, 854 min_bytes, bytes, aad_bytes, pc_bytes; 855 struct gcm_sg_walk gw_in, gw_out; 856 u8 tag[GHASH_DIGEST_SIZE]; 857 858 struct { 859 u32 _[3]; /* reserved */ 860 u32 cv; /* Counter Value */ 861 u8 t[GHASH_DIGEST_SIZE];/* Tag */ 862 u8 h[AES_BLOCK_SIZE]; /* Hash-subkey */ 863 u64 taadl; /* Total AAD Length */ 864 u64 tpcl; /* Total Plain-/Cipher-text Length */ 865 u8 j0[GHASH_BLOCK_SIZE];/* initial counter value */ 866 u8 k[AES_MAX_KEY_SIZE]; /* Key */ 867 } param; 868 869 /* 870 * encrypt 871 * req->src: aad||plaintext 872 * req->dst: aad||ciphertext||tag 873 * decrypt 874 * req->src: aad||ciphertext||tag 875 * req->dst: aad||plaintext, return 0 or -EBADMSG 876 * aad, plaintext and ciphertext may be empty. 877 */ 878 if (flags & CPACF_DECRYPT) 879 pclen -= taglen; 880 len = aadlen + pclen; 881 882 memset(¶m, 0, sizeof(param)); 883 param.cv = 1; 884 param.taadl = aadlen * 8; 885 param.tpcl = pclen * 8; 886 memcpy(param.j0, req->iv, ivsize); 887 *(u32 *)(param.j0 + ivsize) = 1; 888 memcpy(param.k, ctx->key, ctx->key_len); 889 890 gcm_walk_start(&gw_in, req->src, len); 891 gcm_walk_start(&gw_out, req->dst, len); 892 893 do { 894 min_bytes = min_t(unsigned int, 895 aadlen > 0 ? aadlen : pclen, AES_BLOCK_SIZE); 896 in_bytes = gcm_in_walk_go(&gw_in, min_bytes); 897 out_bytes = gcm_out_walk_go(&gw_out, min_bytes); 898 bytes = min(in_bytes, out_bytes); 899 900 if (aadlen + pclen <= bytes) { 901 aad_bytes = aadlen; 902 pc_bytes = pclen; 903 flags |= CPACF_KMA_LAAD | CPACF_KMA_LPC; 904 } else { 905 if (aadlen <= bytes) { 906 aad_bytes = aadlen; 907 pc_bytes = (bytes - aadlen) & 908 ~(AES_BLOCK_SIZE - 1); 909 flags |= CPACF_KMA_LAAD; 910 } else { 911 aad_bytes = bytes & ~(AES_BLOCK_SIZE - 1); 912 pc_bytes = 0; 913 } 914 } 915 916 if (aad_bytes > 0) 917 memcpy(gw_out.ptr, gw_in.ptr, aad_bytes); 918 919 cpacf_kma(ctx->fc | flags, ¶m, 920 gw_out.ptr + aad_bytes, 921 gw_in.ptr + aad_bytes, pc_bytes, 922 gw_in.ptr, aad_bytes); 923 924 n = aad_bytes + pc_bytes; 925 if (gcm_in_walk_done(&gw_in, n) != n) 926 return -ENOMEM; 927 if (gcm_out_walk_done(&gw_out, n) != n) 928 return -ENOMEM; 929 aadlen -= aad_bytes; 930 pclen -= pc_bytes; 931 } while (aadlen + pclen > 0); 932 933 if (flags & CPACF_DECRYPT) { 934 scatterwalk_map_and_copy(tag, req->src, len, taglen, 0); 935 if (crypto_memneq(tag, param.t, taglen)) 936 ret = -EBADMSG; 937 } else 938 scatterwalk_map_and_copy(param.t, req->dst, len, taglen, 1); 939 940 memzero_explicit(¶m, sizeof(param)); 941 return ret; 942 } 943 944 static int gcm_aes_encrypt(struct aead_request *req) 945 { 946 return gcm_aes_crypt(req, CPACF_ENCRYPT); 947 } 948 949 static int gcm_aes_decrypt(struct aead_request *req) 950 { 951 return gcm_aes_crypt(req, CPACF_DECRYPT); 952 } 953 954 static struct aead_alg gcm_aes_aead = { 955 .setkey = gcm_aes_setkey, 956 .setauthsize = gcm_aes_setauthsize, 957 .encrypt = gcm_aes_encrypt, 958 .decrypt = gcm_aes_decrypt, 959 960 .ivsize = GHASH_BLOCK_SIZE - sizeof(u32), 961 .maxauthsize = GHASH_DIGEST_SIZE, 962 .chunksize = AES_BLOCK_SIZE, 963 964 .base = { 965 .cra_blocksize = 1, 966 .cra_ctxsize = sizeof(struct s390_aes_ctx), 967 .cra_priority = 900, 968 .cra_name = "gcm(aes)", 969 .cra_driver_name = "gcm-aes-s390", 970 .cra_module = THIS_MODULE, 971 }, 972 }; 973 974 static struct crypto_alg *aes_s390_alg; 975 static struct skcipher_alg *aes_s390_skcipher_algs[4]; 976 static int aes_s390_skciphers_num; 977 static struct aead_alg *aes_s390_aead_alg; 978 979 static int aes_s390_register_skcipher(struct skcipher_alg *alg) 980 { 981 int ret; 982 983 ret = crypto_register_skcipher(alg); 984 if (!ret) 985 aes_s390_skcipher_algs[aes_s390_skciphers_num++] = alg; 986 return ret; 987 } 988 989 static void aes_s390_fini(void) 990 { 991 if (aes_s390_alg) 992 crypto_unregister_alg(aes_s390_alg); 993 while (aes_s390_skciphers_num--) 994 crypto_unregister_skcipher(aes_s390_skcipher_algs[aes_s390_skciphers_num]); 995 if (ctrblk) 996 free_page((unsigned long) ctrblk); 997 998 if (aes_s390_aead_alg) 999 crypto_unregister_aead(aes_s390_aead_alg); 1000 } 1001 1002 static int __init aes_s390_init(void) 1003 { 1004 int ret; 1005 1006 /* Query available functions for KM, KMC, KMCTR and KMA */ 1007 cpacf_query(CPACF_KM, &km_functions); 1008 cpacf_query(CPACF_KMC, &kmc_functions); 1009 cpacf_query(CPACF_KMCTR, &kmctr_functions); 1010 cpacf_query(CPACF_KMA, &kma_functions); 1011 1012 if (cpacf_test_func(&km_functions, CPACF_KM_AES_128) || 1013 cpacf_test_func(&km_functions, CPACF_KM_AES_192) || 1014 cpacf_test_func(&km_functions, CPACF_KM_AES_256)) { 1015 ret = crypto_register_alg(&aes_alg); 1016 if (ret) 1017 goto out_err; 1018 aes_s390_alg = &aes_alg; 1019 ret = aes_s390_register_skcipher(&ecb_aes_alg); 1020 if (ret) 1021 goto out_err; 1022 } 1023 1024 if (cpacf_test_func(&kmc_functions, CPACF_KMC_AES_128) || 1025 cpacf_test_func(&kmc_functions, CPACF_KMC_AES_192) || 1026 cpacf_test_func(&kmc_functions, CPACF_KMC_AES_256)) { 1027 ret = aes_s390_register_skcipher(&cbc_aes_alg); 1028 if (ret) 1029 goto out_err; 1030 } 1031 1032 if (cpacf_test_func(&km_functions, CPACF_KM_XTS_128) || 1033 cpacf_test_func(&km_functions, CPACF_KM_XTS_256)) { 1034 ret = aes_s390_register_skcipher(&xts_aes_alg); 1035 if (ret) 1036 goto out_err; 1037 } 1038 1039 if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_AES_128) || 1040 cpacf_test_func(&kmctr_functions, CPACF_KMCTR_AES_192) || 1041 cpacf_test_func(&kmctr_functions, CPACF_KMCTR_AES_256)) { 1042 ctrblk = (u8 *) __get_free_page(GFP_KERNEL); 1043 if (!ctrblk) { 1044 ret = -ENOMEM; 1045 goto out_err; 1046 } 1047 ret = aes_s390_register_skcipher(&ctr_aes_alg); 1048 if (ret) 1049 goto out_err; 1050 } 1051 1052 if (cpacf_test_func(&kma_functions, CPACF_KMA_GCM_AES_128) || 1053 cpacf_test_func(&kma_functions, CPACF_KMA_GCM_AES_192) || 1054 cpacf_test_func(&kma_functions, CPACF_KMA_GCM_AES_256)) { 1055 ret = crypto_register_aead(&gcm_aes_aead); 1056 if (ret) 1057 goto out_err; 1058 aes_s390_aead_alg = &gcm_aes_aead; 1059 } 1060 1061 return 0; 1062 out_err: 1063 aes_s390_fini(); 1064 return ret; 1065 } 1066 1067 module_cpu_feature_match(MSA, aes_s390_init); 1068 module_exit(aes_s390_fini); 1069 1070 MODULE_ALIAS_CRYPTO("aes-all"); 1071 1072 MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm"); 1073 MODULE_LICENSE("GPL"); 1074