1 /* 2 * Copyright (c) 2022-2023, STMicroelectronics - All Rights Reserved 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <assert.h> 8 #include <endian.h> 9 #include <errno.h> 10 11 #include <common/debug.h> 12 #include <drivers/auth/crypto_mod.h> 13 #include <drivers/io/io_storage.h> 14 #include <drivers/st/bsec.h> 15 #include <drivers/st/stm32_hash.h> 16 #include <drivers/st/stm32_pka.h> 17 #include <drivers/st/stm32_rng.h> 18 #include <drivers/st/stm32_saes.h> 19 #include <lib/utils.h> 20 #include <lib/xlat_tables/xlat_tables_v2.h> 21 #include <mbedtls/asn1.h> 22 #include <mbedtls/md.h> 23 #include <mbedtls/oid.h> 24 #include <mbedtls/platform.h> 25 #include <mbedtls/x509.h> 26 #include <plat/common/platform.h> 27 #include <tools_share/firmware_encrypted.h> 28 29 #include <platform_def.h> 30 31 #define CRYPTO_HASH_MAX_SIZE 32U 32 #define CRYPTO_SIGN_MAX_SIZE 64U 33 #define CRYPTO_PUBKEY_MAX_SIZE 64U 34 #define CRYPTO_MAX_TAG_SIZE 16U 35 36 /* brainpoolP256t1 OID is not defined in mbedTLS */ 37 #define OID_EC_GRP_BP256T1 MBEDTLS_OID_EC_BRAINPOOL_V1 "\x08" 38 39 #if STM32MP_CRYPTO_ROM_LIB 40 struct stm32mp_auth_ops { 41 uint32_t (*verify_signature)(uint8_t *hash_in, uint8_t *pubkey_in, 42 uint8_t *signature, uint32_t ecc_algo); 43 }; 44 45 static struct stm32mp_auth_ops auth_ops; 46 #endif 47 48 static void crypto_lib_init(void) 49 { 50 boot_api_context_t *boot_context __maybe_unused; 51 int ret; 52 53 NOTICE("TRUSTED_BOARD_BOOT support enabled\n"); 54 55 ret = stm32_hash_register(); 56 if (ret != 0) { 57 ERROR("HASH init (%d)\n", ret); 58 panic(); 59 } 60 61 if (stm32mp_is_closed_device() || stm32mp_is_auth_supported()) { 62 #if STM32MP_CRYPTO_ROM_LIB 63 boot_context = (boot_api_context_t *)stm32mp_get_boot_ctx_address(); 64 auth_ops.verify_signature = boot_context->bootrom_ecdsa_verify_signature; 65 #else 66 /* Use hardware peripherals */ 67 if (stm32_rng_init() != 0) { 68 panic(); 69 } 70 71 if (stm32_saes_driver_init() != 0) { 72 panic(); 73 } 74 75 if (stm32_pka_init() != 0) { 76 panic(); 77 } 78 #endif 79 } 80 } 81 82 static int get_plain_pk_from_asn1(void *pk_ptr, unsigned int pk_len, void **plain_pk, 83 unsigned int *len, int *pk_alg) 84 { 85 int ret; 86 mbedtls_pk_context mbedtls_pk = {0}; 87 unsigned char *p, *end; 88 mbedtls_asn1_buf alg_params = {0}; 89 mbedtls_asn1_buf alg_oid = {0}; 90 91 *plain_pk = NULL; 92 *len = 0U; 93 94 /* Parse the public key */ 95 mbedtls_pk_init(&mbedtls_pk); 96 p = (unsigned char *)pk_ptr; 97 end = (unsigned char *)(p + pk_len); 98 99 ret = mbedtls_asn1_get_tag(&p, end, len, 100 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE); 101 if (ret != 0) { 102 return -EINVAL; 103 } 104 105 end = p + *len; 106 ret = mbedtls_asn1_get_alg(&p, end, &alg_oid, &alg_params); 107 if (ret != 0) { 108 VERBOSE("%s: mbedtls_asn1_get_alg (%d)\n", __func__, ret); 109 return -EINVAL; 110 } 111 112 if (pk_alg != NULL) { 113 if ((strlen(MBEDTLS_OID_EC_GRP_SECP256R1) == alg_params.len) && 114 (memcmp(MBEDTLS_OID_EC_GRP_SECP256R1, alg_params.p, alg_params.len) == 0)) { 115 *pk_alg = BOOT_API_ECDSA_ALGO_TYPE_P256NIST; 116 } else if ((strlen(OID_EC_GRP_BP256T1) == alg_params.len) && 117 (memcmp(OID_EC_GRP_BP256T1, alg_params.p, alg_params.len) == 0)) { 118 *pk_alg = BOOT_API_ECDSA_ALGO_TYPE_BRAINPOOL256; 119 } else { 120 ERROR("%s: Algorithm is not supported\n", __func__); 121 return -EINVAL; 122 } 123 } 124 125 ret = mbedtls_asn1_get_bitstring_null(&p, end, len); 126 if (ret != 0) { 127 VERBOSE("%s: mbedtls_asn1_get_bitstring_null (%d)\n", __func__, ret); 128 return -EINVAL; 129 } 130 131 /* We remove the ident (0x04) first byte. */ 132 if ((*len < 1U) || (p[0] != MBEDTLS_ASN1_OCTET_STRING)) { 133 VERBOSE("%s: not expected len or tag\n", __func__); 134 return -EINVAL; 135 } 136 137 *len = *len - 1U; 138 *plain_pk = p + 1U; 139 140 return 0; 141 } 142 143 #if STM32MP_CRYPTO_ROM_LIB 144 uint32_t verify_signature(uint8_t *hash_in, uint8_t *pubkey_in, 145 uint8_t *signature, uint32_t ecc_algo) 146 { 147 int ret; 148 149 ret = mmap_add_dynamic_region(STM32MP_ROM_BASE, STM32MP_ROM_BASE, 150 STM32MP_ROM_SIZE_2MB_ALIGNED, MT_CODE | MT_SECURE); 151 if (ret != 0) { 152 VERBOSE("%s: mmap_add_dynamic_region (%d)\n", __func__, ret); 153 return CRYPTO_ERR_SIGNATURE; 154 } 155 156 ret = auth_ops.verify_signature(hash_in, pubkey_in, signature, ecc_algo); 157 158 if (ret != BOOT_API_RETURN_OK) { 159 VERBOSE("%s: auth_ops.verify_sign (%d)\n", __func__, ret); 160 ret = CRYPTO_ERR_SIGNATURE; 161 } else { 162 ret = 0; 163 } 164 165 mmap_remove_dynamic_region(STM32MP_ROM_BASE, STM32MP_ROM_SIZE_2MB_ALIGNED); 166 167 return ret; 168 } 169 170 static int crypto_convert_pk(void *full_pk_ptr, unsigned int full_pk_len, 171 void **hashed_pk_ptr, unsigned int *hashed_pk_len) 172 { 173 return get_plain_pk_from_asn1(full_pk_ptr, full_pk_len, hashed_pk_ptr, hashed_pk_len, NULL); 174 } 175 #else /* STM32MP_CRYPTO_ROM_LIB*/ 176 static uint32_t verify_signature(uint8_t *hash_in, uint8_t *pubkey_in, 177 uint8_t *signature, uint32_t ecc_algo) 178 { 179 int ret = -1; 180 enum stm32_pka_ecdsa_curve_id cid; 181 182 switch (ecc_algo) { 183 case BOOT_API_ECDSA_ALGO_TYPE_P256NIST: 184 #if PKA_USE_NIST_P256 185 cid = PKA_NIST_P256; 186 ret = 0; 187 #else 188 WARN("%s nist_p256 requested but not included\n", __func__); 189 #endif 190 break; 191 case BOOT_API_ECDSA_ALGO_TYPE_BRAINPOOL256: 192 #if PKA_USE_BRAINPOOL_P256T1 193 cid = PKA_BRAINPOOL_P256T1; 194 ret = 0; 195 #else 196 WARN("%s brainpool_p256t1 requested but not included\n", __func__); 197 #endif 198 break; 199 default: 200 WARN("%s unexpected ecc_algo(%u)\n", __func__, ecc_algo); 201 break; 202 } 203 204 if (ret < 0) { 205 return CRYPTO_ERR_SIGNATURE; 206 } 207 208 ret = stm32_pka_ecdsa_verif(hash_in, 209 BOOT_API_SHA256_DIGEST_SIZE_IN_BYTES, 210 signature, BOOT_API_ECDSA_SIGNATURE_LEN_IN_BYTES / 2U, 211 signature + BOOT_API_ECDSA_SIGNATURE_LEN_IN_BYTES / 2U, 212 BOOT_API_ECDSA_SIGNATURE_LEN_IN_BYTES / 2U, 213 pubkey_in, BOOT_API_ECDSA_PUB_KEY_LEN_IN_BYTES / 2U, 214 pubkey_in + BOOT_API_ECDSA_PUB_KEY_LEN_IN_BYTES / 2U, 215 BOOT_API_ECDSA_PUB_KEY_LEN_IN_BYTES / 2U, cid); 216 if (ret < 0) { 217 return CRYPTO_ERR_SIGNATURE; 218 } 219 220 return 0; 221 } 222 223 static int crypto_convert_pk(void *full_pk_ptr, unsigned int full_pk_len, 224 void **hashed_pk_ptr, unsigned int *hashed_pk_len) 225 { 226 static uint8_t st_pk[CRYPTO_PUBKEY_MAX_SIZE + sizeof(uint32_t)]; 227 int ret; 228 void *plain_pk; 229 unsigned int len; 230 int curve_id; 231 uint32_t cid; 232 233 ret = get_plain_pk_from_asn1(full_pk_ptr, full_pk_len, &plain_pk, &len, &curve_id); 234 if ((ret != 0) || (len > CRYPTO_PUBKEY_MAX_SIZE)) { 235 return -EINVAL; 236 } 237 238 cid = curve_id; /* we want value of curve_id (1 or 2) in a uint32_t */ 239 240 memcpy(st_pk, &cid, sizeof(cid)); 241 memcpy(st_pk + sizeof(cid), plain_pk, len); 242 243 *hashed_pk_ptr = st_pk; 244 *hashed_pk_len = len + sizeof(cid); 245 246 return 0; 247 } 248 #endif /* STM32MP_CRYPTO_ROM_LIB */ 249 250 static int get_plain_digest_from_asn1(void *digest_ptr, unsigned int digest_len, 251 uint8_t **out, size_t *out_len, mbedtls_md_type_t *md_alg) 252 { 253 int ret; 254 mbedtls_asn1_buf hash_oid, params; 255 size_t len; 256 unsigned char *p, *end; 257 258 *out = NULL; 259 *out_len = 0U; 260 261 /* Digest info should be an MBEDTLS_ASN1_SEQUENCE */ 262 p = (unsigned char *)digest_ptr; 263 end = p + digest_len; 264 ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | 265 MBEDTLS_ASN1_SEQUENCE); 266 if (ret != 0) { 267 return ret; 268 } 269 270 /* Get the hash algorithm */ 271 ret = mbedtls_asn1_get_alg(&p, end, &hash_oid, ¶ms); 272 if (ret != 0) { 273 return ret; 274 } 275 276 ret = mbedtls_oid_get_md_alg(&hash_oid, md_alg); 277 if (ret != 0) { 278 return ret; 279 } 280 281 ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING); 282 if (ret != 0) { 283 return ret; 284 } 285 286 /* Length of hash must match the algorithm's size */ 287 if (len != BOOT_API_SHA256_DIGEST_SIZE_IN_BYTES) { 288 return -1; 289 } 290 291 *out = p; 292 *out_len = len; 293 294 return 0; 295 } 296 297 static int crypto_verify_signature(void *data_ptr, unsigned int data_len, 298 void *sig_ptr, unsigned int sig_len, 299 void *sig_alg, unsigned int sig_alg_len, 300 void *pk_ptr, unsigned int pk_len) 301 { 302 uint8_t image_hash[CRYPTO_HASH_MAX_SIZE] = {0}; 303 uint8_t sig[CRYPTO_SIGN_MAX_SIZE]; 304 uint8_t my_pk[CRYPTO_PUBKEY_MAX_SIZE]; 305 int ret; 306 size_t len; 307 mbedtls_asn1_sequence seq; 308 mbedtls_asn1_sequence *cur; 309 unsigned char *p, *end; 310 int curve_id; 311 mbedtls_asn1_buf sig_oid, sig_params; 312 mbedtls_md_type_t md_alg; 313 mbedtls_pk_type_t pk_alg; 314 size_t bignum_len = sizeof(sig) / 2U; 315 unsigned int seq_num = 0U; 316 317 if (!stm32mp_is_closed_device() && !stm32mp_is_auth_supported()) { 318 return CRYPTO_SUCCESS; 319 } 320 321 /* Get pointers to signature OID and parameters */ 322 p = (unsigned char *)sig_alg; 323 end = (unsigned char *)(p + sig_alg_len); 324 ret = mbedtls_asn1_get_alg(&p, end, &sig_oid, &sig_params); 325 if (ret != 0) { 326 VERBOSE("%s: mbedtls_asn1_get_alg (%d)\n", __func__, ret); 327 return CRYPTO_ERR_SIGNATURE; 328 } 329 330 /* Get the actual signature algorithm (MD + PK) */ 331 ret = mbedtls_oid_get_sig_alg(&sig_oid, &md_alg, &pk_alg); 332 if (ret != 0) { 333 VERBOSE("%s: mbedtls_oid_get_sig_alg (%d)\n", __func__, ret); 334 return CRYPTO_ERR_SIGNATURE; 335 } 336 337 if ((md_alg != MBEDTLS_MD_SHA256) || (pk_alg != MBEDTLS_PK_ECDSA)) { 338 VERBOSE("%s: md_alg=%u pk_alg=%u\n", __func__, md_alg, pk_alg); 339 return CRYPTO_ERR_SIGNATURE; 340 } 341 342 ret = get_plain_pk_from_asn1(pk_ptr, pk_len, &pk_ptr, &pk_len, &curve_id); 343 if (ret != 0) { 344 VERBOSE("%s: get_plain_pk_from_asn1 (%d)\n", __func__, ret); 345 return CRYPTO_ERR_SIGNATURE; 346 } 347 348 /* We expect a known pk_len */ 349 if (pk_len != sizeof(my_pk)) { 350 VERBOSE("%s: pk_len=%u sizeof(my_pk)=%zu)\n", __func__, pk_len, sizeof(my_pk)); 351 return CRYPTO_ERR_SIGNATURE; 352 } 353 354 /* Need to copy as auth_ops.verify_signature 355 * expects aligned public key. 356 */ 357 memcpy(my_pk, pk_ptr, sizeof(my_pk)); 358 359 /* Get the signature (bitstring) */ 360 p = (unsigned char *)sig_ptr; 361 end = (unsigned char *)(p + sig_len); 362 ret = mbedtls_asn1_get_bitstring_null(&p, end, &len); 363 if (ret != 0) { 364 VERBOSE("%s: mbedtls_asn1_get_bitstring_null (%d)\n", __func__, ret); 365 return CRYPTO_ERR_SIGNATURE; 366 } 367 368 /* Get r and s from sequence */ 369 ret = mbedtls_asn1_get_sequence_of(&p, end, &seq, MBEDTLS_ASN1_INTEGER); 370 if (ret != 0) { 371 VERBOSE("%s: mbedtls_asn1_get_sequence_of (%d)\n", __func__, ret); 372 return CRYPTO_ERR_SIGNATURE; 373 } 374 375 /* We expect only 2 integers (r and s) from the sequence */ 376 if (seq.next->next != NULL) { 377 cur = seq.next; 378 mbedtls_asn1_sequence *next; 379 380 VERBOSE("%s: nb seq != 2\n", __func__); 381 /* Free all the sequences */ 382 while (cur != NULL) { 383 next = cur->next; 384 mbedtls_free(cur); 385 cur = next; 386 } 387 388 return CRYPTO_ERR_SIGNATURE; 389 } 390 391 /* 392 * ECDSA signatures are composed of a tuple (R,S) where R and S are between 0 and n. 393 * This means that the R and S can have a maximum of 32 each, but can also be smaller. 394 * Also seen the integer sequence may (sometime) start with 0x00 as MSB, but we can only 395 * manage exactly 2*32 bytes, we remove this higher byte if there are not 00, 396 * we will fail either. 397 */ 398 cur = &seq; 399 memset(sig, 0U, sizeof(sig)); 400 401 while (cur != NULL) { 402 size_t skip = 0U; 403 size_t seek = seq_num * bignum_len; 404 405 if (cur->buf.len > bignum_len) { 406 /* Remove extra 0x00 bytes */ 407 skip = cur->buf.len - bignum_len; 408 } else if (cur->buf.len < bignum_len) { 409 /* Add padding to match HW required size */ 410 seek += (bignum_len % cur->buf.len); 411 } 412 413 if (seek + cur->buf.len > sizeof(sig) + skip) { 414 panic(); 415 } 416 417 memcpy(sig + seek, cur->buf.p + skip, cur->buf.len - skip); 418 cur = cur->next; 419 seq_num++; 420 } 421 422 /* Need to free allocated 'next' in mbedtls_asn1_get_sequence_of */ 423 mbedtls_free(seq.next); 424 425 /* Compute hash for the data covered by the signature */ 426 stm32_hash_init(HASH_SHA256); 427 428 ret = stm32_hash_final_update((uint8_t *)data_ptr, data_len, image_hash); 429 if (ret != 0) { 430 VERBOSE("%s: stm32_hash_final_update (%d)\n", __func__, ret); 431 return CRYPTO_ERR_SIGNATURE; 432 } 433 434 return verify_signature(image_hash, my_pk, sig, curve_id); 435 } 436 437 static int crypto_verify_hash(void *data_ptr, unsigned int data_len, 438 void *digest_info_ptr, 439 unsigned int digest_info_len) 440 { 441 int ret; 442 uint8_t calc_hash[BOOT_API_SHA256_DIGEST_SIZE_IN_BYTES]; 443 unsigned char *p; 444 mbedtls_md_type_t md_alg; 445 size_t len; 446 447 /* we receive an asn1 encapsulated digest, we flatten it */ 448 ret = get_plain_digest_from_asn1(digest_info_ptr, 449 digest_info_len, &p, &len, 450 &md_alg); 451 if ((ret != 0) || (md_alg != MBEDTLS_MD_SHA256) || (len != sizeof(calc_hash))) { 452 return CRYPTO_ERR_HASH; 453 } 454 455 digest_info_ptr = p; 456 digest_info_len = len; 457 458 stm32_hash_init(HASH_SHA256); 459 460 ret = stm32_hash_final_update(data_ptr, data_len, calc_hash); 461 if (ret != 0) { 462 VERBOSE("%s: hash failed\n", __func__); 463 return CRYPTO_ERR_HASH; 464 } 465 466 ret = memcmp(calc_hash, digest_info_ptr, digest_info_len); 467 if (ret != 0) { 468 VERBOSE("%s: not expected digest\n", __func__); 469 ret = CRYPTO_ERR_HASH; 470 } 471 472 return ret; 473 } 474 475 #if !defined(DECRYPTION_SUPPORT_none) 476 static int derive_key(uint8_t *key, size_t *key_len, size_t len, 477 unsigned int *flags, const uint8_t *img_id, size_t img_id_len) 478 { 479 size_t i, j; 480 481 assert(*key_len >= 32U); 482 483 /* 484 * Not a real derivation yet 485 * 486 * But we expect a 32 bytes key, and OTP is only 16 bytes 487 * => duplicate. 488 */ 489 for (i = 0U, j = len; j < 32U; 490 i += sizeof(uint32_t), j += sizeof(uint32_t)) { 491 memcpy(key + j, key + i, sizeof(uint32_t)); 492 } 493 494 *key_len = 32U; 495 /* Variable 'key' store a real key */ 496 *flags = 0U; 497 498 return 0; 499 } 500 501 int plat_get_enc_key_info(enum fw_enc_status_t fw_enc_status, uint8_t *key, 502 size_t *key_len, unsigned int *flags, 503 const uint8_t *img_id, size_t img_id_len) 504 { 505 uint32_t otp_idx; 506 uint32_t otp_len; 507 size_t read_len; 508 size_t i; 509 510 if (fw_enc_status == FW_ENC_WITH_BSSK) { 511 return -EINVAL; 512 } 513 514 if (stm32_get_otp_index(ENCKEY_OTP, &otp_idx, &otp_len) != 0) { 515 VERBOSE("%s: get %s index error\n", __func__, ENCKEY_OTP); 516 return -EINVAL; 517 } 518 519 if (otp_len > (*key_len * CHAR_BIT)) { 520 VERBOSE("%s: length Error otp_len=%u key_len=%u\n", __func__, 521 otp_len, *key_len * CHAR_BIT); 522 return -EINVAL; 523 } 524 525 read_len = otp_len / CHAR_BIT; 526 assert(read_len % sizeof(uint32_t) == 0); 527 528 for (i = 0U; i < read_len / sizeof(uint32_t); i++) { 529 uint32_t tmp; 530 uint32_t otp_val; 531 532 if (stm32_get_otp_value_from_idx(otp_idx + i, &otp_val) != 0) { 533 zeromem(key, *key_len); 534 VERBOSE("%s: unable to read from otp\n", __func__); 535 return -EINVAL; 536 } 537 538 tmp = bswap32(otp_val); 539 memcpy(key + i * sizeof(uint32_t), &tmp, sizeof(tmp)); 540 } 541 542 /* Now we have the OTP values in key till read_len */ 543 544 if (derive_key(key, key_len, read_len, flags, img_id, 545 img_id_len) != 0) { 546 zeromem(key, *key_len); 547 return -EINVAL; 548 } 549 550 return 0; 551 } 552 553 static enum stm32_saes_key_selection select_key(unsigned int key_flags) 554 { 555 if ((key_flags & ENC_KEY_IS_IDENTIFIER) != 0U) { 556 panic(); 557 } 558 559 /* Use the provided key buffer */ 560 return STM32_SAES_KEY_SOFT; 561 } 562 563 static int stm32_decrypt_aes_gcm(void *data, size_t data_len, 564 const void *key, unsigned int key_len, 565 unsigned int key_flags, 566 const void *iv, unsigned int iv_len, 567 const void *tag, unsigned int tag_len) 568 { 569 int ret; 570 struct stm32_saes_context ctx; 571 unsigned char tag_buf[CRYPTO_MAX_TAG_SIZE]; 572 enum stm32_saes_key_selection key_mode; 573 unsigned int diff = 0U; 574 unsigned int i; 575 576 key_mode = select_key(key_flags); 577 578 ret = stm32_saes_init(&ctx, true, STM32_SAES_MODE_GCM, key_mode, key, 579 key_len, iv, iv_len); 580 if (ret != 0) { 581 return CRYPTO_ERR_INIT; 582 } 583 584 ret = stm32_saes_update_assodata(&ctx, true, NULL, 0U); 585 if (ret != 0) { 586 return CRYPTO_ERR_DECRYPTION; 587 } 588 589 ret = stm32_saes_update_load(&ctx, true, data, data, data_len); 590 if (ret != 0) { 591 return CRYPTO_ERR_DECRYPTION; 592 } 593 594 ret = stm32_saes_final(&ctx, tag_buf, sizeof(tag_buf)); 595 if (ret != 0) { 596 return CRYPTO_ERR_DECRYPTION; 597 } 598 599 /* Check tag in "constant-time" */ 600 for (i = 0U; i < tag_len; i++) { 601 diff |= ((const unsigned char *)tag)[i] ^ tag_buf[i]; 602 } 603 604 if (diff != 0U) { 605 return CRYPTO_ERR_DECRYPTION; 606 } 607 608 return CRYPTO_SUCCESS; 609 } 610 611 /* 612 * Authenticated decryption of an image 613 * 614 */ 615 static int crypto_auth_decrypt(enum crypto_dec_algo dec_algo, void *data_ptr, size_t len, 616 const void *key, unsigned int key_len, unsigned int key_flags, 617 const void *iv, unsigned int iv_len, const void *tag, 618 unsigned int tag_len) 619 { 620 int rc = -1; 621 uint32_t real_iv[4]; 622 623 switch (dec_algo) { 624 case CRYPTO_GCM_DECRYPT: 625 /* 626 * GCM expect a Nonce 627 * The AES IV is the nonce (a uint32_t[3]) 628 * then a counter (a uint32_t big endian) 629 * The counter starts at 2. 630 */ 631 memcpy(real_iv, iv, iv_len); 632 real_iv[3] = htobe32(0x2U); 633 634 rc = stm32_decrypt_aes_gcm(data_ptr, len, key, key_len, key_flags, 635 real_iv, sizeof(real_iv), tag, tag_len); 636 break; 637 default: 638 rc = CRYPTO_ERR_DECRYPTION; 639 break; 640 } 641 642 if (rc != 0) { 643 return rc; 644 } 645 646 return CRYPTO_SUCCESS; 647 } 648 649 REGISTER_CRYPTO_LIB("stm32_crypto_lib", 650 crypto_lib_init, 651 crypto_verify_signature, 652 crypto_verify_hash, 653 NULL, 654 crypto_auth_decrypt, 655 crypto_convert_pk); 656 657 #else /* No decryption support */ 658 REGISTER_CRYPTO_LIB("stm32_crypto_lib", 659 crypto_lib_init, 660 crypto_verify_signature, 661 crypto_verify_hash, 662 NULL, 663 NULL, 664 crypto_convert_pk); 665 #endif 666