1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (c) 2013, Google Inc. 4 */ 5 6 #include "mkimage.h" 7 #include <stdio.h> 8 #include <string.h> 9 #include <image.h> 10 #include <time.h> 11 #include <openssl/bn.h> 12 #include <openssl/rsa.h> 13 #include <openssl/pem.h> 14 #include <openssl/err.h> 15 #include <openssl/ssl.h> 16 #include <openssl/evp.h> 17 #include <openssl/engine.h> 18 19 #if OPENSSL_VERSION_NUMBER >= 0x10000000L 20 #define HAVE_ERR_REMOVE_THREAD_STATE 21 #endif 22 23 #if OPENSSL_VERSION_NUMBER < 0x10100000L || \ 24 (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x02070000fL) 25 static void RSA_get0_key(const RSA *r, 26 const BIGNUM **n, const BIGNUM **e, const BIGNUM **d) 27 { 28 if (n != NULL) 29 *n = r->n; 30 if (e != NULL) 31 *e = r->e; 32 if (d != NULL) 33 *d = r->d; 34 } 35 #endif 36 37 static int rsa_err(const char *msg) 38 { 39 unsigned long sslErr = ERR_get_error(); 40 41 fprintf(stderr, "%s", msg); 42 fprintf(stderr, ": %s\n", 43 ERR_error_string(sslErr, 0)); 44 45 return -1; 46 } 47 48 /** 49 * rsa_pem_get_pub_key() - read a public key from a .crt file 50 * 51 * @keydir: Directory containins the key 52 * @name Name of key file (will have a .crt extension) 53 * @rsap Returns RSA object, or NULL on failure 54 * @return 0 if ok, -ve on error (in which case *rsap will be set to NULL) 55 */ 56 static int rsa_pem_get_pub_key(const char *keydir, const char *name, RSA **rsap) 57 { 58 char path[1024]; 59 EVP_PKEY *key; 60 X509 *cert; 61 RSA *rsa; 62 FILE *f; 63 int ret; 64 65 *rsap = NULL; 66 snprintf(path, sizeof(path), "%s/%s.crt", keydir, name); 67 f = fopen(path, "r"); 68 if (!f) { 69 fprintf(stderr, "Couldn't open RSA certificate: '%s': %s\n", 70 path, strerror(errno)); 71 return -EACCES; 72 } 73 74 /* Read the certificate */ 75 cert = NULL; 76 if (!PEM_read_X509(f, &cert, NULL, NULL)) { 77 rsa_err("Couldn't read certificate"); 78 ret = -EINVAL; 79 goto err_cert; 80 } 81 82 /* Get the public key from the certificate. */ 83 key = X509_get_pubkey(cert); 84 if (!key) { 85 rsa_err("Couldn't read public key\n"); 86 ret = -EINVAL; 87 goto err_pubkey; 88 } 89 90 /* Convert to a RSA_style key. */ 91 rsa = EVP_PKEY_get1_RSA(key); 92 if (!rsa) { 93 rsa_err("Couldn't convert to a RSA style key"); 94 ret = -EINVAL; 95 goto err_rsa; 96 } 97 fclose(f); 98 EVP_PKEY_free(key); 99 X509_free(cert); 100 *rsap = rsa; 101 102 return 0; 103 104 err_rsa: 105 EVP_PKEY_free(key); 106 err_pubkey: 107 X509_free(cert); 108 err_cert: 109 fclose(f); 110 return ret; 111 } 112 113 /** 114 * rsa_engine_get_pub_key() - read a public key from given engine 115 * 116 * @keydir: Key prefix 117 * @name Name of key 118 * @engine Engine to use 119 * @rsap Returns RSA object, or NULL on failure 120 * @return 0 if ok, -ve on error (in which case *rsap will be set to NULL) 121 */ 122 static int rsa_engine_get_pub_key(const char *keydir, const char *name, 123 ENGINE *engine, RSA **rsap) 124 { 125 const char *engine_id; 126 char key_id[1024]; 127 EVP_PKEY *key; 128 RSA *rsa; 129 int ret; 130 131 *rsap = NULL; 132 133 engine_id = ENGINE_get_id(engine); 134 135 if (engine_id && !strcmp(engine_id, "pkcs11")) { 136 if (keydir) 137 snprintf(key_id, sizeof(key_id), 138 "pkcs11:%s;object=%s;type=public", 139 keydir, name); 140 else 141 snprintf(key_id, sizeof(key_id), 142 "pkcs11:object=%s;type=public", 143 name); 144 } else { 145 fprintf(stderr, "Engine not supported\n"); 146 return -ENOTSUP; 147 } 148 149 key = ENGINE_load_public_key(engine, key_id, NULL, NULL); 150 if (!key) 151 return rsa_err("Failure loading public key from engine"); 152 153 /* Convert to a RSA_style key. */ 154 rsa = EVP_PKEY_get1_RSA(key); 155 if (!rsa) { 156 rsa_err("Couldn't convert to a RSA style key"); 157 ret = -EINVAL; 158 goto err_rsa; 159 } 160 161 EVP_PKEY_free(key); 162 *rsap = rsa; 163 164 return 0; 165 166 err_rsa: 167 EVP_PKEY_free(key); 168 return ret; 169 } 170 171 /** 172 * rsa_get_pub_key() - read a public key 173 * 174 * @keydir: Directory containing the key (PEM file) or key prefix (engine) 175 * @name Name of key file (will have a .crt extension) 176 * @engine Engine to use 177 * @rsap Returns RSA object, or NULL on failure 178 * @return 0 if ok, -ve on error (in which case *rsap will be set to NULL) 179 */ 180 static int rsa_get_pub_key(const char *keydir, const char *name, 181 ENGINE *engine, RSA **rsap) 182 { 183 if (engine) 184 return rsa_engine_get_pub_key(keydir, name, engine, rsap); 185 return rsa_pem_get_pub_key(keydir, name, rsap); 186 } 187 188 /** 189 * rsa_pem_get_priv_key() - read a private key from a .key file 190 * 191 * @keydir: Directory containing the key 192 * @name Name of key file (will have a .key extension) 193 * @rsap Returns RSA object, or NULL on failure 194 * @return 0 if ok, -ve on error (in which case *rsap will be set to NULL) 195 */ 196 static int rsa_pem_get_priv_key(const char *keydir, const char *name, 197 RSA **rsap) 198 { 199 char path[1024]; 200 RSA *rsa; 201 FILE *f; 202 203 *rsap = NULL; 204 snprintf(path, sizeof(path), "%s/%s.key", keydir, name); 205 f = fopen(path, "r"); 206 if (!f) { 207 fprintf(stderr, "Couldn't open RSA private key: '%s': %s\n", 208 path, strerror(errno)); 209 return -ENOENT; 210 } 211 212 rsa = PEM_read_RSAPrivateKey(f, 0, NULL, path); 213 if (!rsa) { 214 rsa_err("Failure reading private key"); 215 fclose(f); 216 return -EPROTO; 217 } 218 fclose(f); 219 *rsap = rsa; 220 221 return 0; 222 } 223 224 /** 225 * rsa_engine_get_priv_key() - read a private key from given engine 226 * 227 * @keydir: Key prefix 228 * @name Name of key 229 * @engine Engine to use 230 * @rsap Returns RSA object, or NULL on failure 231 * @return 0 if ok, -ve on error (in which case *rsap will be set to NULL) 232 */ 233 static int rsa_engine_get_priv_key(const char *keydir, const char *name, 234 ENGINE *engine, RSA **rsap) 235 { 236 const char *engine_id; 237 char key_id[1024]; 238 EVP_PKEY *key; 239 RSA *rsa; 240 int ret; 241 242 *rsap = NULL; 243 244 engine_id = ENGINE_get_id(engine); 245 246 if (engine_id && !strcmp(engine_id, "pkcs11")) { 247 if (keydir) 248 snprintf(key_id, sizeof(key_id), 249 "pkcs11:%s;object=%s;type=private", 250 keydir, name); 251 else 252 snprintf(key_id, sizeof(key_id), 253 "pkcs11:object=%s;type=private", 254 name); 255 } else { 256 fprintf(stderr, "Engine not supported\n"); 257 return -ENOTSUP; 258 } 259 260 key = ENGINE_load_private_key(engine, key_id, NULL, NULL); 261 if (!key) 262 return rsa_err("Failure loading private key from engine"); 263 264 /* Convert to a RSA_style key. */ 265 rsa = EVP_PKEY_get1_RSA(key); 266 if (!rsa) { 267 rsa_err("Couldn't convert to a RSA style key"); 268 ret = -EINVAL; 269 goto err_rsa; 270 } 271 272 EVP_PKEY_free(key); 273 *rsap = rsa; 274 275 return 0; 276 277 err_rsa: 278 EVP_PKEY_free(key); 279 return ret; 280 } 281 282 /** 283 * rsa_get_priv_key() - read a private key 284 * 285 * @keydir: Directory containing the key (PEM file) or key prefix (engine) 286 * @name Name of key 287 * @engine Engine to use for signing 288 * @rsap Returns RSA object, or NULL on failure 289 * @return 0 if ok, -ve on error (in which case *rsap will be set to NULL) 290 */ 291 static int rsa_get_priv_key(const char *keydir, const char *name, 292 ENGINE *engine, RSA **rsap) 293 { 294 if (engine) 295 return rsa_engine_get_priv_key(keydir, name, engine, rsap); 296 return rsa_pem_get_priv_key(keydir, name, rsap); 297 } 298 299 static int rsa_init(void) 300 { 301 int ret; 302 303 #if OPENSSL_VERSION_NUMBER < 0x10100000L || \ 304 (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x02070000fL) 305 ret = SSL_library_init(); 306 #else 307 ret = OPENSSL_init_ssl(0, NULL); 308 #endif 309 if (!ret) { 310 fprintf(stderr, "Failure to init SSL library\n"); 311 return -1; 312 } 313 #if OPENSSL_VERSION_NUMBER < 0x10100000L || \ 314 (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x02070000fL) 315 SSL_load_error_strings(); 316 317 OpenSSL_add_all_algorithms(); 318 OpenSSL_add_all_digests(); 319 OpenSSL_add_all_ciphers(); 320 #endif 321 322 return 0; 323 } 324 325 static int rsa_engine_init(const char *engine_id, ENGINE **pe) 326 { 327 ENGINE *e; 328 int ret; 329 330 ENGINE_load_builtin_engines(); 331 332 e = ENGINE_by_id(engine_id); 333 if (!e) { 334 fprintf(stderr, "Engine isn't available\n"); 335 ret = -1; 336 goto err_engine_by_id; 337 } 338 339 if (!ENGINE_init(e)) { 340 fprintf(stderr, "Couldn't initialize engine\n"); 341 ret = -1; 342 goto err_engine_init; 343 } 344 345 if (!ENGINE_set_default_RSA(e)) { 346 fprintf(stderr, "Couldn't set engine as default for RSA\n"); 347 ret = -1; 348 goto err_set_rsa; 349 } 350 351 *pe = e; 352 353 return 0; 354 355 err_set_rsa: 356 ENGINE_finish(e); 357 err_engine_init: 358 ENGINE_free(e); 359 err_engine_by_id: 360 #if OPENSSL_VERSION_NUMBER < 0x10100000L || \ 361 (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x02070000fL) 362 ENGINE_cleanup(); 363 #endif 364 return ret; 365 } 366 367 static void rsa_remove(void) 368 { 369 #if OPENSSL_VERSION_NUMBER < 0x10100000L || \ 370 (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x02070000fL) 371 CRYPTO_cleanup_all_ex_data(); 372 ERR_free_strings(); 373 #ifdef HAVE_ERR_REMOVE_THREAD_STATE 374 ERR_remove_thread_state(NULL); 375 #else 376 ERR_remove_state(0); 377 #endif 378 EVP_cleanup(); 379 #endif 380 } 381 382 static void rsa_engine_remove(ENGINE *e) 383 { 384 if (e) { 385 ENGINE_finish(e); 386 ENGINE_free(e); 387 } 388 } 389 390 static int rsa_sign_with_key(RSA *rsa, struct checksum_algo *checksum_algo, 391 const struct image_region region[], int region_count, 392 uint8_t **sigp, uint *sig_size) 393 { 394 EVP_PKEY *key; 395 EVP_MD_CTX *context; 396 int size, ret = 0; 397 uint8_t *sig; 398 int i; 399 400 key = EVP_PKEY_new(); 401 if (!key) 402 return rsa_err("EVP_PKEY object creation failed"); 403 404 if (!EVP_PKEY_set1_RSA(key, rsa)) { 405 ret = rsa_err("EVP key setup failed"); 406 goto err_set; 407 } 408 409 size = EVP_PKEY_size(key); 410 sig = malloc(size); 411 if (!sig) { 412 fprintf(stderr, "Out of memory for signature (%d bytes)\n", 413 size); 414 ret = -ENOMEM; 415 goto err_alloc; 416 } 417 418 context = EVP_MD_CTX_create(); 419 if (!context) { 420 ret = rsa_err("EVP context creation failed"); 421 goto err_create; 422 } 423 EVP_MD_CTX_init(context); 424 if (!EVP_SignInit(context, checksum_algo->calculate_sign())) { 425 ret = rsa_err("Signer setup failed"); 426 goto err_sign; 427 } 428 429 for (i = 0; i < region_count; i++) { 430 if (!EVP_SignUpdate(context, region[i].data, region[i].size)) { 431 ret = rsa_err("Signing data failed"); 432 goto err_sign; 433 } 434 } 435 436 if (!EVP_SignFinal(context, sig, sig_size, key)) { 437 ret = rsa_err("Could not obtain signature"); 438 goto err_sign; 439 } 440 #if OPENSSL_VERSION_NUMBER < 0x10100000L || \ 441 (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x02070000fL) 442 EVP_MD_CTX_cleanup(context); 443 #else 444 EVP_MD_CTX_reset(context); 445 #endif 446 EVP_MD_CTX_destroy(context); 447 EVP_PKEY_free(key); 448 449 debug("Got signature: %d bytes, expected %d\n", *sig_size, size); 450 *sigp = sig; 451 *sig_size = size; 452 453 return 0; 454 455 err_sign: 456 EVP_MD_CTX_destroy(context); 457 err_create: 458 free(sig); 459 err_alloc: 460 err_set: 461 EVP_PKEY_free(key); 462 return ret; 463 } 464 465 int rsa_sign(struct image_sign_info *info, 466 const struct image_region region[], int region_count, 467 uint8_t **sigp, uint *sig_len) 468 { 469 RSA *rsa; 470 ENGINE *e = NULL; 471 int ret; 472 473 ret = rsa_init(); 474 if (ret) 475 return ret; 476 477 if (info->engine_id) { 478 ret = rsa_engine_init(info->engine_id, &e); 479 if (ret) 480 goto err_engine; 481 } 482 483 ret = rsa_get_priv_key(info->keydir, info->keyname, e, &rsa); 484 if (ret) 485 goto err_priv; 486 ret = rsa_sign_with_key(rsa, info->checksum, region, 487 region_count, sigp, sig_len); 488 if (ret) 489 goto err_sign; 490 491 RSA_free(rsa); 492 if (info->engine_id) 493 rsa_engine_remove(e); 494 rsa_remove(); 495 496 return ret; 497 498 err_sign: 499 RSA_free(rsa); 500 err_priv: 501 if (info->engine_id) 502 rsa_engine_remove(e); 503 err_engine: 504 rsa_remove(); 505 return ret; 506 } 507 508 /* 509 * rsa_get_exponent(): - Get the public exponent from an RSA key 510 */ 511 static int rsa_get_exponent(RSA *key, uint64_t *e) 512 { 513 int ret; 514 BIGNUM *bn_te; 515 const BIGNUM *key_e; 516 uint64_t te; 517 518 ret = -EINVAL; 519 bn_te = NULL; 520 521 if (!e) 522 goto cleanup; 523 524 RSA_get0_key(key, NULL, &key_e, NULL); 525 if (BN_num_bits(key_e) > 64) 526 goto cleanup; 527 528 *e = BN_get_word(key_e); 529 530 if (BN_num_bits(key_e) < 33) { 531 ret = 0; 532 goto cleanup; 533 } 534 535 bn_te = BN_dup(key_e); 536 if (!bn_te) 537 goto cleanup; 538 539 if (!BN_rshift(bn_te, bn_te, 32)) 540 goto cleanup; 541 542 if (!BN_mask_bits(bn_te, 32)) 543 goto cleanup; 544 545 te = BN_get_word(bn_te); 546 te <<= 32; 547 *e |= te; 548 ret = 0; 549 550 cleanup: 551 if (bn_te) 552 BN_free(bn_te); 553 554 return ret; 555 } 556 557 /* 558 * rsa_get_params(): - Get the important parameters of an RSA public key 559 */ 560 int rsa_get_params(RSA *key, uint64_t *exponent, uint32_t *n0_invp, 561 BIGNUM **modulusp, BIGNUM **r_squaredp) 562 { 563 BIGNUM *big1, *big2, *big32, *big2_32; 564 BIGNUM *n, *r, *r_squared, *tmp; 565 const BIGNUM *key_n; 566 BN_CTX *bn_ctx = BN_CTX_new(); 567 int ret = 0; 568 569 /* Initialize BIGNUMs */ 570 big1 = BN_new(); 571 big2 = BN_new(); 572 big32 = BN_new(); 573 r = BN_new(); 574 r_squared = BN_new(); 575 tmp = BN_new(); 576 big2_32 = BN_new(); 577 n = BN_new(); 578 if (!big1 || !big2 || !big32 || !r || !r_squared || !tmp || !big2_32 || 579 !n) { 580 fprintf(stderr, "Out of memory (bignum)\n"); 581 return -ENOMEM; 582 } 583 584 if (0 != rsa_get_exponent(key, exponent)) 585 ret = -1; 586 587 RSA_get0_key(key, &key_n, NULL, NULL); 588 if (!BN_copy(n, key_n) || !BN_set_word(big1, 1L) || 589 !BN_set_word(big2, 2L) || !BN_set_word(big32, 32L)) 590 ret = -1; 591 592 /* big2_32 = 2^32 */ 593 if (!BN_exp(big2_32, big2, big32, bn_ctx)) 594 ret = -1; 595 596 /* Calculate n0_inv = -1 / n[0] mod 2^32 */ 597 if (!BN_mod_inverse(tmp, n, big2_32, bn_ctx) || 598 !BN_sub(tmp, big2_32, tmp)) 599 ret = -1; 600 *n0_invp = BN_get_word(tmp); 601 602 /* Calculate R = 2^(# of key bits) */ 603 if (!BN_set_word(tmp, BN_num_bits(n)) || 604 !BN_exp(r, big2, tmp, bn_ctx)) 605 ret = -1; 606 607 /* Calculate r_squared = R^2 mod n */ 608 if (!BN_copy(r_squared, r) || 609 !BN_mul(tmp, r_squared, r, bn_ctx) || 610 !BN_mod(r_squared, tmp, n, bn_ctx)) 611 ret = -1; 612 613 *modulusp = n; 614 *r_squaredp = r_squared; 615 616 BN_free(big1); 617 BN_free(big2); 618 BN_free(big32); 619 BN_free(r); 620 BN_free(tmp); 621 BN_free(big2_32); 622 if (ret) { 623 fprintf(stderr, "Bignum operations failed\n"); 624 return -ENOMEM; 625 } 626 627 return ret; 628 } 629 630 static int fdt_add_bignum(void *blob, int noffset, const char *prop_name, 631 BIGNUM *num, int num_bits) 632 { 633 int nwords = num_bits / 32; 634 int size; 635 uint32_t *buf, *ptr; 636 BIGNUM *tmp, *big2, *big32, *big2_32; 637 BN_CTX *ctx; 638 int ret; 639 640 tmp = BN_new(); 641 big2 = BN_new(); 642 big32 = BN_new(); 643 big2_32 = BN_new(); 644 645 /* 646 * Note: This code assumes that all of the above succeed, or all fail. 647 * In practice memory allocations generally do not fail (unless the 648 * process is killed), so it does not seem worth handling each of these 649 * as a separate case. Technicaly this could leak memory on failure, 650 * but a) it won't happen in practice, and b) it doesn't matter as we 651 * will immediately exit with a failure code. 652 */ 653 if (!tmp || !big2 || !big32 || !big2_32) { 654 fprintf(stderr, "Out of memory (bignum)\n"); 655 return -ENOMEM; 656 } 657 ctx = BN_CTX_new(); 658 if (!tmp) { 659 fprintf(stderr, "Out of memory (bignum context)\n"); 660 return -ENOMEM; 661 } 662 BN_set_word(big2, 2L); 663 BN_set_word(big32, 32L); 664 BN_exp(big2_32, big2, big32, ctx); /* B = 2^32 */ 665 666 size = nwords * sizeof(uint32_t); 667 buf = malloc(size); 668 if (!buf) { 669 fprintf(stderr, "Out of memory (%d bytes)\n", size); 670 return -ENOMEM; 671 } 672 673 /* Write out modulus as big endian array of integers */ 674 for (ptr = buf + nwords - 1; ptr >= buf; ptr--) { 675 BN_mod(tmp, num, big2_32, ctx); /* n = N mod B */ 676 *ptr = cpu_to_fdt32(BN_get_word(tmp)); 677 BN_rshift(num, num, 32); /* N = N/B */ 678 } 679 680 /* 681 * We try signing with successively increasing size values, so this 682 * might fail several times 683 */ 684 ret = fdt_setprop(blob, noffset, prop_name, buf, size); 685 free(buf); 686 BN_free(tmp); 687 BN_free(big2); 688 BN_free(big32); 689 BN_free(big2_32); 690 691 return ret ? -FDT_ERR_NOSPACE : 0; 692 } 693 694 int rsa_add_verify_data(struct image_sign_info *info, void *keydest) 695 { 696 BIGNUM *modulus, *r_squared; 697 uint64_t exponent; 698 uint32_t n0_inv; 699 int parent, node; 700 char name[100]; 701 int ret; 702 int bits; 703 RSA *rsa; 704 ENGINE *e = NULL; 705 706 debug("%s: Getting verification data\n", __func__); 707 if (info->engine_id) { 708 ret = rsa_engine_init(info->engine_id, &e); 709 if (ret) 710 return ret; 711 } 712 ret = rsa_get_pub_key(info->keydir, info->keyname, e, &rsa); 713 if (ret) 714 goto err_get_pub_key; 715 ret = rsa_get_params(rsa, &exponent, &n0_inv, &modulus, &r_squared); 716 if (ret) 717 goto err_get_params; 718 bits = BN_num_bits(modulus); 719 parent = fdt_subnode_offset(keydest, 0, FIT_SIG_NODENAME); 720 if (parent == -FDT_ERR_NOTFOUND) { 721 parent = fdt_add_subnode(keydest, 0, FIT_SIG_NODENAME); 722 if (parent < 0) { 723 ret = parent; 724 if (ret != -FDT_ERR_NOSPACE) { 725 fprintf(stderr, "Couldn't create signature node: %s\n", 726 fdt_strerror(parent)); 727 } 728 } 729 } 730 if (ret) 731 goto done; 732 733 /* Either create or overwrite the named key node */ 734 snprintf(name, sizeof(name), "key-%s", info->keyname); 735 node = fdt_subnode_offset(keydest, parent, name); 736 if (node == -FDT_ERR_NOTFOUND) { 737 node = fdt_add_subnode(keydest, parent, name); 738 if (node < 0) { 739 ret = node; 740 if (ret != -FDT_ERR_NOSPACE) { 741 fprintf(stderr, "Could not create key subnode: %s\n", 742 fdt_strerror(node)); 743 } 744 } 745 } else if (node < 0) { 746 fprintf(stderr, "Cannot select keys parent: %s\n", 747 fdt_strerror(node)); 748 ret = node; 749 } 750 751 if (!ret) { 752 ret = fdt_setprop_string(keydest, node, "key-name-hint", 753 info->keyname); 754 } 755 if (!ret) 756 ret = fdt_setprop_u32(keydest, node, "rsa,num-bits", bits); 757 if (!ret) 758 ret = fdt_setprop_u32(keydest, node, "rsa,n0-inverse", n0_inv); 759 if (!ret) { 760 ret = fdt_setprop_u64(keydest, node, "rsa,exponent", exponent); 761 } 762 if (!ret) { 763 ret = fdt_add_bignum(keydest, node, "rsa,modulus", modulus, 764 bits); 765 } 766 if (!ret) { 767 ret = fdt_add_bignum(keydest, node, "rsa,r-squared", r_squared, 768 bits); 769 } 770 if (!ret) { 771 ret = fdt_setprop_string(keydest, node, FIT_ALGO_PROP, 772 info->name); 773 } 774 if (!ret && info->require_keys) { 775 ret = fdt_setprop_string(keydest, node, "required", 776 info->require_keys); 777 } 778 done: 779 BN_free(modulus); 780 BN_free(r_squared); 781 if (ret) 782 ret = ret == -FDT_ERR_NOSPACE ? -ENOSPC : -EIO; 783 err_get_params: 784 RSA_free(rsa); 785 err_get_pub_key: 786 if (info->engine_id) 787 rsa_engine_remove(e); 788 789 return ret; 790 } 791