1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2020 Hannes Reinecke, SUSE Linux 4 */ 5 6 #include <linux/module.h> 7 #include <linux/crc32.h> 8 #include <linux/base64.h> 9 #include <linux/prandom.h> 10 #include <linux/scatterlist.h> 11 #include <linux/unaligned.h> 12 #include <crypto/hash.h> 13 #include <crypto/dh.h> 14 #include <crypto/hkdf.h> 15 #include <linux/nvme.h> 16 #include <linux/nvme-auth.h> 17 18 static u32 nvme_dhchap_seqnum; 19 static DEFINE_MUTEX(nvme_dhchap_mutex); 20 21 u32 nvme_auth_get_seqnum(void) 22 { 23 u32 seqnum; 24 25 mutex_lock(&nvme_dhchap_mutex); 26 if (!nvme_dhchap_seqnum) 27 nvme_dhchap_seqnum = get_random_u32(); 28 else { 29 nvme_dhchap_seqnum++; 30 if (!nvme_dhchap_seqnum) 31 nvme_dhchap_seqnum++; 32 } 33 seqnum = nvme_dhchap_seqnum; 34 mutex_unlock(&nvme_dhchap_mutex); 35 return seqnum; 36 } 37 EXPORT_SYMBOL_GPL(nvme_auth_get_seqnum); 38 39 static struct nvme_auth_dhgroup_map { 40 const char name[16]; 41 const char kpp[16]; 42 } dhgroup_map[] = { 43 [NVME_AUTH_DHGROUP_NULL] = { 44 .name = "null", .kpp = "null" }, 45 [NVME_AUTH_DHGROUP_2048] = { 46 .name = "ffdhe2048", .kpp = "ffdhe2048(dh)" }, 47 [NVME_AUTH_DHGROUP_3072] = { 48 .name = "ffdhe3072", .kpp = "ffdhe3072(dh)" }, 49 [NVME_AUTH_DHGROUP_4096] = { 50 .name = "ffdhe4096", .kpp = "ffdhe4096(dh)" }, 51 [NVME_AUTH_DHGROUP_6144] = { 52 .name = "ffdhe6144", .kpp = "ffdhe6144(dh)" }, 53 [NVME_AUTH_DHGROUP_8192] = { 54 .name = "ffdhe8192", .kpp = "ffdhe8192(dh)" }, 55 }; 56 57 const char *nvme_auth_dhgroup_name(u8 dhgroup_id) 58 { 59 if (dhgroup_id >= ARRAY_SIZE(dhgroup_map)) 60 return NULL; 61 return dhgroup_map[dhgroup_id].name; 62 } 63 EXPORT_SYMBOL_GPL(nvme_auth_dhgroup_name); 64 65 const char *nvme_auth_dhgroup_kpp(u8 dhgroup_id) 66 { 67 if (dhgroup_id >= ARRAY_SIZE(dhgroup_map)) 68 return NULL; 69 return dhgroup_map[dhgroup_id].kpp; 70 } 71 EXPORT_SYMBOL_GPL(nvme_auth_dhgroup_kpp); 72 73 u8 nvme_auth_dhgroup_id(const char *dhgroup_name) 74 { 75 int i; 76 77 if (!dhgroup_name || !strlen(dhgroup_name)) 78 return NVME_AUTH_DHGROUP_INVALID; 79 for (i = 0; i < ARRAY_SIZE(dhgroup_map); i++) { 80 if (!strlen(dhgroup_map[i].name)) 81 continue; 82 if (!strncmp(dhgroup_map[i].name, dhgroup_name, 83 strlen(dhgroup_map[i].name))) 84 return i; 85 } 86 return NVME_AUTH_DHGROUP_INVALID; 87 } 88 EXPORT_SYMBOL_GPL(nvme_auth_dhgroup_id); 89 90 static struct nvme_dhchap_hash_map { 91 int len; 92 const char hmac[15]; 93 const char digest[8]; 94 } hash_map[] = { 95 [NVME_AUTH_HASH_SHA256] = { 96 .len = 32, 97 .hmac = "hmac(sha256)", 98 .digest = "sha256", 99 }, 100 [NVME_AUTH_HASH_SHA384] = { 101 .len = 48, 102 .hmac = "hmac(sha384)", 103 .digest = "sha384", 104 }, 105 [NVME_AUTH_HASH_SHA512] = { 106 .len = 64, 107 .hmac = "hmac(sha512)", 108 .digest = "sha512", 109 }, 110 }; 111 112 const char *nvme_auth_hmac_name(u8 hmac_id) 113 { 114 if (hmac_id >= ARRAY_SIZE(hash_map)) 115 return NULL; 116 return hash_map[hmac_id].hmac; 117 } 118 EXPORT_SYMBOL_GPL(nvme_auth_hmac_name); 119 120 const char *nvme_auth_digest_name(u8 hmac_id) 121 { 122 if (hmac_id >= ARRAY_SIZE(hash_map)) 123 return NULL; 124 return hash_map[hmac_id].digest; 125 } 126 EXPORT_SYMBOL_GPL(nvme_auth_digest_name); 127 128 u8 nvme_auth_hmac_id(const char *hmac_name) 129 { 130 int i; 131 132 if (!hmac_name || !strlen(hmac_name)) 133 return NVME_AUTH_HASH_INVALID; 134 135 for (i = 0; i < ARRAY_SIZE(hash_map); i++) { 136 if (!strlen(hash_map[i].hmac)) 137 continue; 138 if (!strncmp(hash_map[i].hmac, hmac_name, 139 strlen(hash_map[i].hmac))) 140 return i; 141 } 142 return NVME_AUTH_HASH_INVALID; 143 } 144 EXPORT_SYMBOL_GPL(nvme_auth_hmac_id); 145 146 size_t nvme_auth_hmac_hash_len(u8 hmac_id) 147 { 148 if (hmac_id >= ARRAY_SIZE(hash_map)) 149 return 0; 150 return hash_map[hmac_id].len; 151 } 152 EXPORT_SYMBOL_GPL(nvme_auth_hmac_hash_len); 153 154 u32 nvme_auth_key_struct_size(u32 key_len) 155 { 156 struct nvme_dhchap_key key; 157 158 return struct_size(&key, key, key_len); 159 } 160 EXPORT_SYMBOL_GPL(nvme_auth_key_struct_size); 161 162 struct nvme_dhchap_key *nvme_auth_extract_key(unsigned char *secret, 163 u8 key_hash) 164 { 165 struct nvme_dhchap_key *key; 166 unsigned char *p; 167 u32 crc; 168 int ret, key_len; 169 size_t allocated_len = strlen(secret); 170 171 /* Secret might be affixed with a ':' */ 172 p = strrchr(secret, ':'); 173 if (p) 174 allocated_len = p - secret; 175 key = nvme_auth_alloc_key(allocated_len, 0); 176 if (!key) 177 return ERR_PTR(-ENOMEM); 178 179 key_len = base64_decode(secret, allocated_len, key->key); 180 if (key_len < 0) { 181 pr_debug("base64 key decoding error %d\n", 182 key_len); 183 ret = key_len; 184 goto out_free_secret; 185 } 186 187 if (key_len != 36 && key_len != 52 && 188 key_len != 68) { 189 pr_err("Invalid key len %d\n", key_len); 190 ret = -EINVAL; 191 goto out_free_secret; 192 } 193 194 /* The last four bytes is the CRC in little-endian format */ 195 key_len -= 4; 196 /* 197 * The linux implementation doesn't do pre- and post-increments, 198 * so we have to do it manually. 199 */ 200 crc = ~crc32(~0, key->key, key_len); 201 202 if (get_unaligned_le32(key->key + key_len) != crc) { 203 pr_err("key crc mismatch (key %08x, crc %08x)\n", 204 get_unaligned_le32(key->key + key_len), crc); 205 ret = -EKEYREJECTED; 206 goto out_free_secret; 207 } 208 key->len = key_len; 209 key->hash = key_hash; 210 return key; 211 out_free_secret: 212 nvme_auth_free_key(key); 213 return ERR_PTR(ret); 214 } 215 EXPORT_SYMBOL_GPL(nvme_auth_extract_key); 216 217 struct nvme_dhchap_key *nvme_auth_alloc_key(u32 len, u8 hash) 218 { 219 u32 num_bytes = nvme_auth_key_struct_size(len); 220 struct nvme_dhchap_key *key = kzalloc(num_bytes, GFP_KERNEL); 221 222 if (key) { 223 key->len = len; 224 key->hash = hash; 225 } 226 return key; 227 } 228 EXPORT_SYMBOL_GPL(nvme_auth_alloc_key); 229 230 void nvme_auth_free_key(struct nvme_dhchap_key *key) 231 { 232 if (!key) 233 return; 234 kfree_sensitive(key); 235 } 236 EXPORT_SYMBOL_GPL(nvme_auth_free_key); 237 238 struct nvme_dhchap_key *nvme_auth_transform_key( 239 struct nvme_dhchap_key *key, char *nqn) 240 { 241 const char *hmac_name; 242 struct crypto_shash *key_tfm; 243 struct shash_desc *shash; 244 struct nvme_dhchap_key *transformed_key; 245 int ret, key_len; 246 247 if (!key) { 248 pr_warn("No key specified\n"); 249 return ERR_PTR(-ENOKEY); 250 } 251 if (key->hash == 0) { 252 key_len = nvme_auth_key_struct_size(key->len); 253 transformed_key = kmemdup(key, key_len, GFP_KERNEL); 254 if (!transformed_key) 255 return ERR_PTR(-ENOMEM); 256 return transformed_key; 257 } 258 hmac_name = nvme_auth_hmac_name(key->hash); 259 if (!hmac_name) { 260 pr_warn("Invalid key hash id %d\n", key->hash); 261 return ERR_PTR(-EINVAL); 262 } 263 264 key_tfm = crypto_alloc_shash(hmac_name, 0, 0); 265 if (IS_ERR(key_tfm)) 266 return ERR_CAST(key_tfm); 267 268 shash = kmalloc(sizeof(struct shash_desc) + 269 crypto_shash_descsize(key_tfm), 270 GFP_KERNEL); 271 if (!shash) { 272 ret = -ENOMEM; 273 goto out_free_key; 274 } 275 276 key_len = crypto_shash_digestsize(key_tfm); 277 transformed_key = nvme_auth_alloc_key(key_len, key->hash); 278 if (!transformed_key) { 279 ret = -ENOMEM; 280 goto out_free_shash; 281 } 282 283 shash->tfm = key_tfm; 284 ret = crypto_shash_setkey(key_tfm, key->key, key->len); 285 if (ret < 0) 286 goto out_free_transformed_key; 287 ret = crypto_shash_init(shash); 288 if (ret < 0) 289 goto out_free_transformed_key; 290 ret = crypto_shash_update(shash, nqn, strlen(nqn)); 291 if (ret < 0) 292 goto out_free_transformed_key; 293 ret = crypto_shash_update(shash, "NVMe-over-Fabrics", 17); 294 if (ret < 0) 295 goto out_free_transformed_key; 296 ret = crypto_shash_final(shash, transformed_key->key); 297 if (ret < 0) 298 goto out_free_transformed_key; 299 300 kfree(shash); 301 crypto_free_shash(key_tfm); 302 303 return transformed_key; 304 305 out_free_transformed_key: 306 nvme_auth_free_key(transformed_key); 307 out_free_shash: 308 kfree(shash); 309 out_free_key: 310 crypto_free_shash(key_tfm); 311 312 return ERR_PTR(ret); 313 } 314 EXPORT_SYMBOL_GPL(nvme_auth_transform_key); 315 316 static int nvme_auth_hash_skey(int hmac_id, u8 *skey, size_t skey_len, u8 *hkey) 317 { 318 const char *digest_name; 319 struct crypto_shash *tfm; 320 int ret; 321 322 digest_name = nvme_auth_digest_name(hmac_id); 323 if (!digest_name) { 324 pr_debug("%s: failed to get digest for %d\n", __func__, 325 hmac_id); 326 return -EINVAL; 327 } 328 tfm = crypto_alloc_shash(digest_name, 0, 0); 329 if (IS_ERR(tfm)) 330 return -ENOMEM; 331 332 ret = crypto_shash_tfm_digest(tfm, skey, skey_len, hkey); 333 if (ret < 0) 334 pr_debug("%s: Failed to hash digest len %zu\n", __func__, 335 skey_len); 336 337 crypto_free_shash(tfm); 338 return ret; 339 } 340 341 int nvme_auth_augmented_challenge(u8 hmac_id, u8 *skey, size_t skey_len, 342 u8 *challenge, u8 *aug, size_t hlen) 343 { 344 struct crypto_shash *tfm; 345 u8 *hashed_key; 346 const char *hmac_name; 347 int ret; 348 349 hashed_key = kmalloc(hlen, GFP_KERNEL); 350 if (!hashed_key) 351 return -ENOMEM; 352 353 ret = nvme_auth_hash_skey(hmac_id, skey, 354 skey_len, hashed_key); 355 if (ret < 0) 356 goto out_free_key; 357 358 hmac_name = nvme_auth_hmac_name(hmac_id); 359 if (!hmac_name) { 360 pr_warn("%s: invalid hash algorithm %d\n", 361 __func__, hmac_id); 362 ret = -EINVAL; 363 goto out_free_key; 364 } 365 366 tfm = crypto_alloc_shash(hmac_name, 0, 0); 367 if (IS_ERR(tfm)) { 368 ret = PTR_ERR(tfm); 369 goto out_free_key; 370 } 371 372 ret = crypto_shash_setkey(tfm, hashed_key, hlen); 373 if (ret) 374 goto out_free_hash; 375 376 ret = crypto_shash_tfm_digest(tfm, challenge, hlen, aug); 377 out_free_hash: 378 crypto_free_shash(tfm); 379 out_free_key: 380 kfree_sensitive(hashed_key); 381 return ret; 382 } 383 EXPORT_SYMBOL_GPL(nvme_auth_augmented_challenge); 384 385 int nvme_auth_gen_privkey(struct crypto_kpp *dh_tfm, u8 dh_gid) 386 { 387 int ret; 388 389 ret = crypto_kpp_set_secret(dh_tfm, NULL, 0); 390 if (ret) 391 pr_debug("failed to set private key, error %d\n", ret); 392 393 return ret; 394 } 395 EXPORT_SYMBOL_GPL(nvme_auth_gen_privkey); 396 397 int nvme_auth_gen_pubkey(struct crypto_kpp *dh_tfm, 398 u8 *host_key, size_t host_key_len) 399 { 400 struct kpp_request *req; 401 struct crypto_wait wait; 402 struct scatterlist dst; 403 int ret; 404 405 req = kpp_request_alloc(dh_tfm, GFP_KERNEL); 406 if (!req) 407 return -ENOMEM; 408 409 crypto_init_wait(&wait); 410 kpp_request_set_input(req, NULL, 0); 411 sg_init_one(&dst, host_key, host_key_len); 412 kpp_request_set_output(req, &dst, host_key_len); 413 kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, 414 crypto_req_done, &wait); 415 416 ret = crypto_wait_req(crypto_kpp_generate_public_key(req), &wait); 417 kpp_request_free(req); 418 return ret; 419 } 420 EXPORT_SYMBOL_GPL(nvme_auth_gen_pubkey); 421 422 int nvme_auth_gen_shared_secret(struct crypto_kpp *dh_tfm, 423 u8 *ctrl_key, size_t ctrl_key_len, 424 u8 *sess_key, size_t sess_key_len) 425 { 426 struct kpp_request *req; 427 struct crypto_wait wait; 428 struct scatterlist src, dst; 429 int ret; 430 431 req = kpp_request_alloc(dh_tfm, GFP_KERNEL); 432 if (!req) 433 return -ENOMEM; 434 435 crypto_init_wait(&wait); 436 sg_init_one(&src, ctrl_key, ctrl_key_len); 437 kpp_request_set_input(req, &src, ctrl_key_len); 438 sg_init_one(&dst, sess_key, sess_key_len); 439 kpp_request_set_output(req, &dst, sess_key_len); 440 kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, 441 crypto_req_done, &wait); 442 443 ret = crypto_wait_req(crypto_kpp_compute_shared_secret(req), &wait); 444 445 kpp_request_free(req); 446 return ret; 447 } 448 EXPORT_SYMBOL_GPL(nvme_auth_gen_shared_secret); 449 450 int nvme_auth_generate_key(u8 *secret, struct nvme_dhchap_key **ret_key) 451 { 452 struct nvme_dhchap_key *key; 453 u8 key_hash; 454 455 if (!secret) { 456 *ret_key = NULL; 457 return 0; 458 } 459 460 if (sscanf(secret, "DHHC-1:%hhd:%*s:", &key_hash) != 1) 461 return -EINVAL; 462 463 /* Pass in the secret without the 'DHHC-1:XX:' prefix */ 464 key = nvme_auth_extract_key(secret + 10, key_hash); 465 if (IS_ERR(key)) { 466 *ret_key = NULL; 467 return PTR_ERR(key); 468 } 469 470 *ret_key = key; 471 return 0; 472 } 473 EXPORT_SYMBOL_GPL(nvme_auth_generate_key); 474 475 /** 476 * nvme_auth_generate_psk - Generate a PSK for TLS 477 * @hmac_id: Hash function identifier 478 * @skey: Session key 479 * @skey_len: Length of @skey 480 * @c1: Value of challenge C1 481 * @c2: Value of challenge C2 482 * @hash_len: Hash length of the hash algorithm 483 * @ret_psk: Pointer too the resulting generated PSK 484 * @ret_len: length of @ret_psk 485 * 486 * Generate a PSK for TLS as specified in NVMe base specification, section 487 * 8.13.5.9: Generated PSK for TLS 488 * 489 * The generated PSK for TLS shall be computed applying the HMAC function 490 * using the hash function H( ) selected by the HashID parameter in the 491 * DH-HMAC-CHAP_Challenge message with the session key KS as key to the 492 * concatenation of the two challenges C1 and C2 (i.e., generated 493 * PSK = HMAC(KS, C1 || C2)). 494 * 495 * Returns 0 on success with a valid generated PSK pointer in @ret_psk and 496 * the length of @ret_psk in @ret_len, or a negative error number otherwise. 497 */ 498 int nvme_auth_generate_psk(u8 hmac_id, u8 *skey, size_t skey_len, 499 u8 *c1, u8 *c2, size_t hash_len, u8 **ret_psk, size_t *ret_len) 500 { 501 struct crypto_shash *tfm; 502 SHASH_DESC_ON_STACK(shash, tfm); 503 u8 *psk; 504 const char *hmac_name; 505 int ret, psk_len; 506 507 if (!c1 || !c2) 508 return -EINVAL; 509 510 hmac_name = nvme_auth_hmac_name(hmac_id); 511 if (!hmac_name) { 512 pr_warn("%s: invalid hash algorithm %d\n", 513 __func__, hmac_id); 514 return -EINVAL; 515 } 516 517 tfm = crypto_alloc_shash(hmac_name, 0, 0); 518 if (IS_ERR(tfm)) 519 return PTR_ERR(tfm); 520 521 psk_len = crypto_shash_digestsize(tfm); 522 psk = kzalloc(psk_len, GFP_KERNEL); 523 if (!psk) { 524 ret = -ENOMEM; 525 goto out_free_tfm; 526 } 527 528 shash->tfm = tfm; 529 ret = crypto_shash_setkey(tfm, skey, skey_len); 530 if (ret) 531 goto out_free_psk; 532 533 ret = crypto_shash_init(shash); 534 if (ret) 535 goto out_free_psk; 536 537 ret = crypto_shash_update(shash, c1, hash_len); 538 if (ret) 539 goto out_free_psk; 540 541 ret = crypto_shash_update(shash, c2, hash_len); 542 if (ret) 543 goto out_free_psk; 544 545 ret = crypto_shash_final(shash, psk); 546 if (!ret) { 547 *ret_psk = psk; 548 *ret_len = psk_len; 549 } 550 551 out_free_psk: 552 if (ret) 553 kfree_sensitive(psk); 554 out_free_tfm: 555 crypto_free_shash(tfm); 556 557 return ret; 558 } 559 EXPORT_SYMBOL_GPL(nvme_auth_generate_psk); 560 561 /** 562 * nvme_auth_generate_digest - Generate TLS PSK digest 563 * @hmac_id: Hash function identifier 564 * @psk: Generated input PSK 565 * @psk_len: Length of @psk 566 * @subsysnqn: NQN of the subsystem 567 * @hostnqn: NQN of the host 568 * @ret_digest: Pointer to the returned digest 569 * 570 * Generate a TLS PSK digest as specified in TP8018 Section 3.6.1.3: 571 * TLS PSK and PSK identity Derivation 572 * 573 * The PSK digest shall be computed by encoding in Base64 (refer to RFC 574 * 4648) the result of the application of the HMAC function using the hash 575 * function specified in item 4 above (ie the hash function of the cipher 576 * suite associated with the PSK identity) with the PSK as HMAC key to the 577 * concatenation of: 578 * - the NQN of the host (i.e., NQNh) not including the null terminator; 579 * - a space character; 580 * - the NQN of the NVM subsystem (i.e., NQNc) not including the null 581 * terminator; 582 * - a space character; and 583 * - the seventeen ASCII characters "NVMe-over-Fabrics" 584 * (i.e., <PSK digest> = Base64(HMAC(PSK, NQNh || " " || NQNc || " " || 585 * "NVMe-over-Fabrics"))). 586 * The length of the PSK digest depends on the hash function used to compute 587 * it as follows: 588 * - If the SHA-256 hash function is used, the resulting PSK digest is 44 589 * characters long; or 590 * - If the SHA-384 hash function is used, the resulting PSK digest is 64 591 * characters long. 592 * 593 * Returns 0 on success with a valid digest pointer in @ret_digest, or a 594 * negative error number on failure. 595 */ 596 int nvme_auth_generate_digest(u8 hmac_id, u8 *psk, size_t psk_len, 597 char *subsysnqn, char *hostnqn, u8 **ret_digest) 598 { 599 struct crypto_shash *tfm; 600 SHASH_DESC_ON_STACK(shash, tfm); 601 u8 *digest, *enc; 602 const char *hmac_name; 603 size_t digest_len, hmac_len; 604 int ret; 605 606 if (WARN_ON(!subsysnqn || !hostnqn)) 607 return -EINVAL; 608 609 hmac_name = nvme_auth_hmac_name(hmac_id); 610 if (!hmac_name) { 611 pr_warn("%s: invalid hash algorithm %d\n", 612 __func__, hmac_id); 613 return -EINVAL; 614 } 615 616 switch (nvme_auth_hmac_hash_len(hmac_id)) { 617 case 32: 618 hmac_len = 44; 619 break; 620 case 48: 621 hmac_len = 64; 622 break; 623 default: 624 pr_warn("%s: invalid hash algorithm '%s'\n", 625 __func__, hmac_name); 626 return -EINVAL; 627 } 628 629 enc = kzalloc(hmac_len + 1, GFP_KERNEL); 630 if (!enc) 631 return -ENOMEM; 632 633 tfm = crypto_alloc_shash(hmac_name, 0, 0); 634 if (IS_ERR(tfm)) { 635 ret = PTR_ERR(tfm); 636 goto out_free_enc; 637 } 638 639 digest_len = crypto_shash_digestsize(tfm); 640 digest = kzalloc(digest_len, GFP_KERNEL); 641 if (!digest) { 642 ret = -ENOMEM; 643 goto out_free_tfm; 644 } 645 646 shash->tfm = tfm; 647 ret = crypto_shash_setkey(tfm, psk, psk_len); 648 if (ret) 649 goto out_free_digest; 650 651 ret = crypto_shash_init(shash); 652 if (ret) 653 goto out_free_digest; 654 655 ret = crypto_shash_update(shash, hostnqn, strlen(hostnqn)); 656 if (ret) 657 goto out_free_digest; 658 659 ret = crypto_shash_update(shash, " ", 1); 660 if (ret) 661 goto out_free_digest; 662 663 ret = crypto_shash_update(shash, subsysnqn, strlen(subsysnqn)); 664 if (ret) 665 goto out_free_digest; 666 667 ret = crypto_shash_update(shash, " NVMe-over-Fabrics", 18); 668 if (ret) 669 goto out_free_digest; 670 671 ret = crypto_shash_final(shash, digest); 672 if (ret) 673 goto out_free_digest; 674 675 ret = base64_encode(digest, digest_len, enc); 676 if (ret < hmac_len) { 677 ret = -ENOKEY; 678 goto out_free_digest; 679 } 680 *ret_digest = enc; 681 ret = 0; 682 683 out_free_digest: 684 kfree_sensitive(digest); 685 out_free_tfm: 686 crypto_free_shash(tfm); 687 out_free_enc: 688 if (ret) 689 kfree_sensitive(enc); 690 691 return ret; 692 } 693 EXPORT_SYMBOL_GPL(nvme_auth_generate_digest); 694 695 MODULE_DESCRIPTION("NVMe Authentication framework"); 696 MODULE_LICENSE("GPL v2"); 697