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 36static u8 *ctrblk; 37static DEFINE_MUTEX(ctrblk_lock); 38 39static cpacf_mask_t km_functions, kmc_functions, kmctr_functions, 40 kma_functions; 41 42struct 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 52struct 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 60struct 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 71static 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 83static 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 104static 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 115static 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 127static 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 144static 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 152static 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 174static 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 187static 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 200static 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 221static 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 243static int ecb_aes_encrypt(struct skcipher_request *req) 244{ 245 return ecb_aes_crypt(req, 0); 246} 247 248static int ecb_aes_decrypt(struct skcipher_request *req) 249{ 250 return ecb_aes_crypt(req, CPACF_DECRYPT); 251} 252 253static 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 272static 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 279static 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 296static 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 317static 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 349static int cbc_aes_encrypt(struct skcipher_request *req) 350{ 351 return cbc_aes_crypt(req, 0); 352} 353 354static int cbc_aes_decrypt(struct skcipher_request *req) 355{ 356 return cbc_aes_crypt(req, CPACF_DECRYPT); 357} 358 359static 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 377static 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 389static 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 421static 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 479static int xts_aes_encrypt(struct skcipher_request *req) 480{ 481 return xts_aes_crypt(req, 0); 482} 483 484static int xts_aes_decrypt(struct skcipher_request *req) 485{ 486 return xts_aes_crypt(req, CPACF_DECRYPT); 487} 488 489static 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 507static 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 514static 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 532static 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 553static 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 568static 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 memset(buf, 0, AES_BLOCK_SIZE); 604 memcpy(buf, walk.src.virt.addr, nbytes); 605 cpacf_kmctr(sctx->fc, sctx->key, buf, buf, 606 AES_BLOCK_SIZE, walk.iv); 607 memcpy(walk.dst.virt.addr, buf, nbytes); 608 crypto_inc(walk.iv, AES_BLOCK_SIZE); 609 ret = skcipher_walk_done(&walk, 0); 610 } 611 612 return ret; 613} 614 615static struct skcipher_alg ctr_aes_alg = { 616 .base.cra_name = "ctr(aes)", 617 .base.cra_driver_name = "ctr-aes-s390", 618 .base.cra_priority = 402, /* ecb-aes-s390 + 1 */ 619 .base.cra_flags = CRYPTO_ALG_NEED_FALLBACK, 620 .base.cra_blocksize = 1, 621 .base.cra_ctxsize = sizeof(struct s390_aes_ctx), 622 .base.cra_module = THIS_MODULE, 623 .init = fallback_init_skcipher, 624 .exit = fallback_exit_skcipher, 625 .min_keysize = AES_MIN_KEY_SIZE, 626 .max_keysize = AES_MAX_KEY_SIZE, 627 .ivsize = AES_BLOCK_SIZE, 628 .setkey = ctr_aes_set_key, 629 .encrypt = ctr_aes_crypt, 630 .decrypt = ctr_aes_crypt, 631 .chunksize = AES_BLOCK_SIZE, 632}; 633 634static int gcm_aes_setkey(struct crypto_aead *tfm, const u8 *key, 635 unsigned int keylen) 636{ 637 struct s390_aes_ctx *ctx = crypto_aead_ctx(tfm); 638 639 switch (keylen) { 640 case AES_KEYSIZE_128: 641 ctx->fc = CPACF_KMA_GCM_AES_128; 642 break; 643 case AES_KEYSIZE_192: 644 ctx->fc = CPACF_KMA_GCM_AES_192; 645 break; 646 case AES_KEYSIZE_256: 647 ctx->fc = CPACF_KMA_GCM_AES_256; 648 break; 649 default: 650 return -EINVAL; 651 } 652 653 memcpy(ctx->key, key, keylen); 654 ctx->key_len = keylen; 655 return 0; 656} 657 658static int gcm_aes_setauthsize(struct crypto_aead *tfm, unsigned int authsize) 659{ 660 switch (authsize) { 661 case 4: 662 case 8: 663 case 12: 664 case 13: 665 case 14: 666 case 15: 667 case 16: 668 break; 669 default: 670 return -EINVAL; 671 } 672 673 return 0; 674} 675 676static void gcm_walk_start(struct gcm_sg_walk *gw, struct scatterlist *sg, 677 unsigned int len) 678{ 679 memset(gw, 0, sizeof(*gw)); 680 gw->walk_bytes_remain = len; 681 scatterwalk_start(&gw->walk, sg); 682} 683 684static inline unsigned int _gcm_sg_clamp_and_map(struct gcm_sg_walk *gw) 685{ 686 struct scatterlist *nextsg; 687 688 gw->walk_bytes = scatterwalk_clamp(&gw->walk, gw->walk_bytes_remain); 689 while (!gw->walk_bytes) { 690 nextsg = sg_next(gw->walk.sg); 691 if (!nextsg) 692 return 0; 693 scatterwalk_start(&gw->walk, nextsg); 694 gw->walk_bytes = scatterwalk_clamp(&gw->walk, 695 gw->walk_bytes_remain); 696 } 697 gw->walk_ptr = scatterwalk_map(&gw->walk); 698 return gw->walk_bytes; 699} 700 701static inline void _gcm_sg_unmap_and_advance(struct gcm_sg_walk *gw, 702 unsigned int nbytes) 703{ 704 gw->walk_bytes_remain -= nbytes; 705 scatterwalk_unmap(gw->walk_ptr); 706 scatterwalk_advance(&gw->walk, nbytes); 707 scatterwalk_done(&gw->walk, 0, gw->walk_bytes_remain); 708 gw->walk_ptr = NULL; 709} 710 711static int gcm_in_walk_go(struct gcm_sg_walk *gw, unsigned int minbytesneeded) 712{ 713 int n; 714 715 if (gw->buf_bytes && gw->buf_bytes >= minbytesneeded) { 716 gw->ptr = gw->buf; 717 gw->nbytes = gw->buf_bytes; 718 goto out; 719 } 720 721 if (gw->walk_bytes_remain == 0) { 722 gw->ptr = NULL; 723 gw->nbytes = 0; 724 goto out; 725 } 726 727 if (!_gcm_sg_clamp_and_map(gw)) { 728 gw->ptr = NULL; 729 gw->nbytes = 0; 730 goto out; 731 } 732 733 if (!gw->buf_bytes && gw->walk_bytes >= minbytesneeded) { 734 gw->ptr = gw->walk_ptr; 735 gw->nbytes = gw->walk_bytes; 736 goto out; 737 } 738 739 while (1) { 740 n = min(gw->walk_bytes, AES_BLOCK_SIZE - gw->buf_bytes); 741 memcpy(gw->buf + gw->buf_bytes, gw->walk_ptr, n); 742 gw->buf_bytes += n; 743 _gcm_sg_unmap_and_advance(gw, n); 744 if (gw->buf_bytes >= minbytesneeded) { 745 gw->ptr = gw->buf; 746 gw->nbytes = gw->buf_bytes; 747 goto out; 748 } 749 if (!_gcm_sg_clamp_and_map(gw)) { 750 gw->ptr = NULL; 751 gw->nbytes = 0; 752 goto out; 753 } 754 } 755 756out: 757 return gw->nbytes; 758} 759 760static int gcm_out_walk_go(struct gcm_sg_walk *gw, unsigned int minbytesneeded) 761{ 762 if (gw->walk_bytes_remain == 0) { 763 gw->ptr = NULL; 764 gw->nbytes = 0; 765 goto out; 766 } 767 768 if (!_gcm_sg_clamp_and_map(gw)) { 769 gw->ptr = NULL; 770 gw->nbytes = 0; 771 goto out; 772 } 773 774 if (gw->walk_bytes >= minbytesneeded) { 775 gw->ptr = gw->walk_ptr; 776 gw->nbytes = gw->walk_bytes; 777 goto out; 778 } 779 780 scatterwalk_unmap(gw->walk_ptr); 781 gw->walk_ptr = NULL; 782 783 gw->ptr = gw->buf; 784 gw->nbytes = sizeof(gw->buf); 785 786out: 787 return gw->nbytes; 788} 789 790static int gcm_in_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone) 791{ 792 if (gw->ptr == NULL) 793 return 0; 794 795 if (gw->ptr == gw->buf) { 796 int n = gw->buf_bytes - bytesdone; 797 if (n > 0) { 798 memmove(gw->buf, gw->buf + bytesdone, n); 799 gw->buf_bytes = n; 800 } else 801 gw->buf_bytes = 0; 802 } else 803 _gcm_sg_unmap_and_advance(gw, bytesdone); 804 805 return bytesdone; 806} 807 808static int gcm_out_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone) 809{ 810 int i, n; 811 812 if (gw->ptr == NULL) 813 return 0; 814 815 if (gw->ptr == gw->buf) { 816 for (i = 0; i < bytesdone; i += n) { 817 if (!_gcm_sg_clamp_and_map(gw)) 818 return i; 819 n = min(gw->walk_bytes, bytesdone - i); 820 memcpy(gw->walk_ptr, gw->buf + i, n); 821 _gcm_sg_unmap_and_advance(gw, n); 822 } 823 } else 824 _gcm_sg_unmap_and_advance(gw, bytesdone); 825 826 return bytesdone; 827} 828 829static int gcm_aes_crypt(struct aead_request *req, unsigned int flags) 830{ 831 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 832 struct s390_aes_ctx *ctx = crypto_aead_ctx(tfm); 833 unsigned int ivsize = crypto_aead_ivsize(tfm); 834 unsigned int taglen = crypto_aead_authsize(tfm); 835 unsigned int aadlen = req->assoclen; 836 unsigned int pclen = req->cryptlen; 837 int ret = 0; 838 839 unsigned int n, len, in_bytes, out_bytes, 840 min_bytes, bytes, aad_bytes, pc_bytes; 841 struct gcm_sg_walk gw_in, gw_out; 842 u8 tag[GHASH_DIGEST_SIZE]; 843 844 struct { 845 u32 _[3]; /* reserved */ 846 u32 cv; /* Counter Value */ 847 u8 t[GHASH_DIGEST_SIZE];/* Tag */ 848 u8 h[AES_BLOCK_SIZE]; /* Hash-subkey */ 849 u64 taadl; /* Total AAD Length */ 850 u64 tpcl; /* Total Plain-/Cipher-text Length */ 851 u8 j0[GHASH_BLOCK_SIZE];/* initial counter value */ 852 u8 k[AES_MAX_KEY_SIZE]; /* Key */ 853 } param; 854 855 /* 856 * encrypt 857 * req->src: aad||plaintext 858 * req->dst: aad||ciphertext||tag 859 * decrypt 860 * req->src: aad||ciphertext||tag 861 * req->dst: aad||plaintext, return 0 or -EBADMSG 862 * aad, plaintext and ciphertext may be empty. 863 */ 864 if (flags & CPACF_DECRYPT) 865 pclen -= taglen; 866 len = aadlen + pclen; 867 868 memset(¶m, 0, sizeof(param)); 869 param.cv = 1; 870 param.taadl = aadlen * 8; 871 param.tpcl = pclen * 8; 872 memcpy(param.j0, req->iv, ivsize); 873 *(u32 *)(param.j0 + ivsize) = 1; 874 memcpy(param.k, ctx->key, ctx->key_len); 875 876 gcm_walk_start(&gw_in, req->src, len); 877 gcm_walk_start(&gw_out, req->dst, len); 878 879 do { 880 min_bytes = min_t(unsigned int, 881 aadlen > 0 ? aadlen : pclen, AES_BLOCK_SIZE); 882 in_bytes = gcm_in_walk_go(&gw_in, min_bytes); 883 out_bytes = gcm_out_walk_go(&gw_out, min_bytes); 884 bytes = min(in_bytes, out_bytes); 885 886 if (aadlen + pclen <= bytes) { 887 aad_bytes = aadlen; 888 pc_bytes = pclen; 889 flags |= CPACF_KMA_LAAD | CPACF_KMA_LPC; 890 } else { 891 if (aadlen <= bytes) { 892 aad_bytes = aadlen; 893 pc_bytes = (bytes - aadlen) & 894 ~(AES_BLOCK_SIZE - 1); 895 flags |= CPACF_KMA_LAAD; 896 } else { 897 aad_bytes = bytes & ~(AES_BLOCK_SIZE - 1); 898 pc_bytes = 0; 899 } 900 } 901 902 if (aad_bytes > 0) 903 memcpy(gw_out.ptr, gw_in.ptr, aad_bytes); 904 905 cpacf_kma(ctx->fc | flags, ¶m, 906 gw_out.ptr + aad_bytes, 907 gw_in.ptr + aad_bytes, pc_bytes, 908 gw_in.ptr, aad_bytes); 909 910 n = aad_bytes + pc_bytes; 911 if (gcm_in_walk_done(&gw_in, n) != n) 912 return -ENOMEM; 913 if (gcm_out_walk_done(&gw_out, n) != n) 914 return -ENOMEM; 915 aadlen -= aad_bytes; 916 pclen -= pc_bytes; 917 } while (aadlen + pclen > 0); 918 919 if (flags & CPACF_DECRYPT) { 920 scatterwalk_map_and_copy(tag, req->src, len, taglen, 0); 921 if (crypto_memneq(tag, param.t, taglen)) 922 ret = -EBADMSG; 923 } else 924 scatterwalk_map_and_copy(param.t, req->dst, len, taglen, 1); 925 926 memzero_explicit(¶m, sizeof(param)); 927 return ret; 928} 929 930static int gcm_aes_encrypt(struct aead_request *req) 931{ 932 return gcm_aes_crypt(req, CPACF_ENCRYPT); 933} 934 935static int gcm_aes_decrypt(struct aead_request *req) 936{ 937 return gcm_aes_crypt(req, CPACF_DECRYPT); 938} 939 940static struct aead_alg gcm_aes_aead = { 941 .setkey = gcm_aes_setkey, 942 .setauthsize = gcm_aes_setauthsize, 943 .encrypt = gcm_aes_encrypt, 944 .decrypt = gcm_aes_decrypt, 945 946 .ivsize = GHASH_BLOCK_SIZE - sizeof(u32), 947 .maxauthsize = GHASH_DIGEST_SIZE, 948 .chunksize = AES_BLOCK_SIZE, 949 950 .base = { 951 .cra_blocksize = 1, 952 .cra_ctxsize = sizeof(struct s390_aes_ctx), 953 .cra_priority = 900, 954 .cra_name = "gcm(aes)", 955 .cra_driver_name = "gcm-aes-s390", 956 .cra_module = THIS_MODULE, 957 }, 958}; 959 960static struct crypto_alg *aes_s390_alg; 961static struct skcipher_alg *aes_s390_skcipher_algs[4]; 962static int aes_s390_skciphers_num; 963static struct aead_alg *aes_s390_aead_alg; 964 965static int aes_s390_register_skcipher(struct skcipher_alg *alg) 966{ 967 int ret; 968 969 ret = crypto_register_skcipher(alg); 970 if (!ret) 971 aes_s390_skcipher_algs[aes_s390_skciphers_num++] = alg; 972 return ret; 973} 974 975static void aes_s390_fini(void) 976{ 977 if (aes_s390_alg) 978 crypto_unregister_alg(aes_s390_alg); 979 while (aes_s390_skciphers_num--) 980 crypto_unregister_skcipher(aes_s390_skcipher_algs[aes_s390_skciphers_num]); 981 if (ctrblk) 982 free_page((unsigned long) ctrblk); 983 984 if (aes_s390_aead_alg) 985 crypto_unregister_aead(aes_s390_aead_alg); 986} 987 988static int __init aes_s390_init(void) 989{ 990 int ret; 991 992 /* Query available functions for KM, KMC, KMCTR and KMA */ 993 cpacf_query(CPACF_KM, &km_functions); 994 cpacf_query(CPACF_KMC, &kmc_functions); 995 cpacf_query(CPACF_KMCTR, &kmctr_functions); 996 cpacf_query(CPACF_KMA, &kma_functions); 997 998 if (cpacf_test_func(&km_functions, CPACF_KM_AES_128) || 999 cpacf_test_func(&km_functions, CPACF_KM_AES_192) || 1000 cpacf_test_func(&km_functions, CPACF_KM_AES_256)) { 1001 ret = crypto_register_alg(&aes_alg); 1002 if (ret) 1003 goto out_err; 1004 aes_s390_alg = &aes_alg; 1005 ret = aes_s390_register_skcipher(&ecb_aes_alg); 1006 if (ret) 1007 goto out_err; 1008 } 1009 1010 if (cpacf_test_func(&kmc_functions, CPACF_KMC_AES_128) || 1011 cpacf_test_func(&kmc_functions, CPACF_KMC_AES_192) || 1012 cpacf_test_func(&kmc_functions, CPACF_KMC_AES_256)) { 1013 ret = aes_s390_register_skcipher(&cbc_aes_alg); 1014 if (ret) 1015 goto out_err; 1016 } 1017 1018 if (cpacf_test_func(&km_functions, CPACF_KM_XTS_128) || 1019 cpacf_test_func(&km_functions, CPACF_KM_XTS_256)) { 1020 ret = aes_s390_register_skcipher(&xts_aes_alg); 1021 if (ret) 1022 goto out_err; 1023 } 1024 1025 if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_AES_128) || 1026 cpacf_test_func(&kmctr_functions, CPACF_KMCTR_AES_192) || 1027 cpacf_test_func(&kmctr_functions, CPACF_KMCTR_AES_256)) { 1028 ctrblk = (u8 *) __get_free_page(GFP_KERNEL); 1029 if (!ctrblk) { 1030 ret = -ENOMEM; 1031 goto out_err; 1032 } 1033 ret = aes_s390_register_skcipher(&ctr_aes_alg); 1034 if (ret) 1035 goto out_err; 1036 } 1037 1038 if (cpacf_test_func(&kma_functions, CPACF_KMA_GCM_AES_128) || 1039 cpacf_test_func(&kma_functions, CPACF_KMA_GCM_AES_192) || 1040 cpacf_test_func(&kma_functions, CPACF_KMA_GCM_AES_256)) { 1041 ret = crypto_register_aead(&gcm_aes_aead); 1042 if (ret) 1043 goto out_err; 1044 aes_s390_aead_alg = &gcm_aes_aead; 1045 } 1046 1047 return 0; 1048out_err: 1049 aes_s390_fini(); 1050 return ret; 1051} 1052 1053module_cpu_feature_match(MSA, aes_s390_init); 1054module_exit(aes_s390_fini); 1055 1056MODULE_ALIAS_CRYPTO("aes-all"); 1057 1058MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm"); 1059MODULE_LICENSE("GPL"); 1060