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