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)
RSA_get0_key(const RSA * r,const BIGNUM ** n,const BIGNUM ** e,const BIGNUM ** d)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
rsa_err(const char * msg)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 */
rsa_pem_get_pub_key(const char * keydir,const char * name,RSA ** rsap)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 */
rsa_engine_get_pub_key(const char * keydir,const char * name,ENGINE * engine,RSA ** rsap)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 */
rsa_get_pub_key(const char * keydir,const char * name,ENGINE * engine,RSA ** rsap)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 */
rsa_pem_get_priv_key(const char * keydir,const char * name,RSA ** rsap)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 */
rsa_engine_get_priv_key(const char * keydir,const char * name,ENGINE * engine,RSA ** rsap)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 */
rsa_get_priv_key(const char * keydir,const char * name,ENGINE * engine,RSA ** rsap)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
rsa_init(void)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
rsa_engine_init(const char * engine_id,ENGINE ** pe)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
rsa_remove(void)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
rsa_engine_remove(ENGINE * e)382 static void rsa_engine_remove(ENGINE *e)
383 {
384 if (e) {
385 ENGINE_finish(e);
386 ENGINE_free(e);
387 }
388 }
389
rsa_sign_with_key(RSA * rsa,struct padding_algo * padding_algo,struct checksum_algo * checksum_algo,const struct image_region region[],int region_count,uint8_t ** sigp,uint * sig_size)390 static int rsa_sign_with_key(RSA *rsa, struct padding_algo *padding_algo,
391 struct checksum_algo *checksum_algo,
392 const struct image_region region[], int region_count,
393 uint8_t **sigp, uint *sig_size)
394 {
395 EVP_PKEY *key;
396 EVP_PKEY_CTX *ckey;
397 EVP_MD_CTX *context;
398 int ret = 0;
399 size_t size;
400 uint8_t *sig;
401 int i;
402
403 key = EVP_PKEY_new();
404 if (!key)
405 return rsa_err("EVP_PKEY object creation failed");
406
407 if (!EVP_PKEY_set1_RSA(key, rsa)) {
408 ret = rsa_err("EVP key setup failed");
409 goto err_set;
410 }
411
412 size = EVP_PKEY_size(key);
413 sig = malloc(size);
414 if (!sig) {
415 fprintf(stderr, "Out of memory for signature (%zu bytes)\n",
416 size);
417 ret = -ENOMEM;
418 goto err_alloc;
419 }
420
421 context = EVP_MD_CTX_create();
422 if (!context) {
423 ret = rsa_err("EVP context creation failed");
424 goto err_create;
425 }
426 EVP_MD_CTX_init(context);
427
428 ckey = EVP_PKEY_CTX_new(key, NULL);
429 if (!ckey) {
430 ret = rsa_err("EVP key context creation failed");
431 goto err_create;
432 }
433
434 if (EVP_DigestSignInit(context, &ckey,
435 checksum_algo->calculate_sign(),
436 NULL, key) <= 0) {
437 ret = rsa_err("Signer setup failed");
438 goto err_sign;
439 }
440
441 #ifdef CONFIG_FIT_ENABLE_RSASSA_PSS_SUPPORT
442 if (padding_algo && !strcmp(padding_algo->name, "pss")) {
443 if (EVP_PKEY_CTX_set_rsa_padding(ckey,
444 RSA_PKCS1_PSS_PADDING) <= 0) {
445 ret = rsa_err("Signer padding setup failed");
446 goto err_sign;
447 }
448 }
449 #endif /* CONFIG_FIT_ENABLE_RSASSA_PSS_SUPPORT */
450
451 for (i = 0; i < region_count; i++) {
452 if (!EVP_DigestSignUpdate(context, region[i].data,
453 region[i].size)) {
454 ret = rsa_err("Signing data failed");
455 goto err_sign;
456 }
457 }
458
459 if (!EVP_DigestSignFinal(context, sig, &size)) {
460 ret = rsa_err("Could not obtain signature");
461 goto err_sign;
462 }
463
464 #if OPENSSL_VERSION_NUMBER < 0x10100000L || \
465 (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x02070000fL)
466 EVP_MD_CTX_cleanup(context);
467 #else
468 EVP_MD_CTX_reset(context);
469 #endif
470 EVP_MD_CTX_destroy(context);
471 EVP_PKEY_free(key);
472
473 debug("Got signature: %d bytes, expected %zu\n", *sig_size, size);
474 *sigp = sig;
475 *sig_size = size;
476
477 return 0;
478
479 err_sign:
480 EVP_MD_CTX_destroy(context);
481 err_create:
482 free(sig);
483 err_alloc:
484 err_set:
485 EVP_PKEY_free(key);
486 return ret;
487 }
488
rsa_sign(struct image_sign_info * info,const struct image_region region[],int region_count,uint8_t ** sigp,uint * sig_len)489 int rsa_sign(struct image_sign_info *info,
490 const struct image_region region[], int region_count,
491 uint8_t **sigp, uint *sig_len)
492 {
493 RSA *rsa;
494 ENGINE *e = NULL;
495 int ret;
496
497 ret = rsa_init();
498 if (ret)
499 return ret;
500
501 if (info->engine_id) {
502 ret = rsa_engine_init(info->engine_id, &e);
503 if (ret)
504 goto err_engine;
505 }
506
507 ret = rsa_get_priv_key(info->keydir, info->keyname, e, &rsa);
508 if (ret)
509 goto err_priv;
510 ret = rsa_sign_with_key(rsa, info->padding, info->checksum, region,
511 region_count, sigp, sig_len);
512 if (ret)
513 goto err_sign;
514
515 RSA_free(rsa);
516 if (info->engine_id)
517 rsa_engine_remove(e);
518 rsa_remove();
519
520 return ret;
521
522 err_sign:
523 RSA_free(rsa);
524 err_priv:
525 if (info->engine_id)
526 rsa_engine_remove(e);
527 err_engine:
528 rsa_remove();
529 return ret;
530 }
531
532 /*
533 * rsa_get_exponent(): - Get the public exponent from an RSA key
534 */
rsa_get_exponent(RSA * key,uint64_t * e)535 static int rsa_get_exponent(RSA *key, uint64_t *e)
536 {
537 int ret;
538 BIGNUM *bn_te;
539 const BIGNUM *key_e;
540 uint64_t te;
541
542 ret = -EINVAL;
543 bn_te = NULL;
544
545 if (!e)
546 goto cleanup;
547
548 RSA_get0_key(key, NULL, &key_e, NULL);
549 if (BN_num_bits(key_e) > 64)
550 goto cleanup;
551
552 *e = BN_get_word(key_e);
553
554 if (BN_num_bits(key_e) < 33) {
555 ret = 0;
556 goto cleanup;
557 }
558
559 bn_te = BN_dup(key_e);
560 if (!bn_te)
561 goto cleanup;
562
563 if (!BN_rshift(bn_te, bn_te, 32))
564 goto cleanup;
565
566 if (!BN_mask_bits(bn_te, 32))
567 goto cleanup;
568
569 te = BN_get_word(bn_te);
570 te <<= 32;
571 *e |= te;
572 ret = 0;
573
574 cleanup:
575 if (bn_te)
576 BN_free(bn_te);
577
578 return ret;
579 }
580
581 /*
582 * rsa_get_params(): - Get the important parameters of an RSA public key
583 */
rsa_get_params(RSA * key,uint64_t * exponent,uint32_t * n0_invp,BIGNUM ** modulusp,BIGNUM ** r_squaredp)584 int rsa_get_params(RSA *key, uint64_t *exponent, uint32_t *n0_invp,
585 BIGNUM **modulusp, BIGNUM **r_squaredp)
586 {
587 BIGNUM *big1, *big2, *big32, *big2_32;
588 BIGNUM *n, *r, *r_squared, *tmp;
589 const BIGNUM *key_n;
590 BN_CTX *bn_ctx = BN_CTX_new();
591 int ret = 0;
592
593 /* Initialize BIGNUMs */
594 big1 = BN_new();
595 big2 = BN_new();
596 big32 = BN_new();
597 r = BN_new();
598 r_squared = BN_new();
599 tmp = BN_new();
600 big2_32 = BN_new();
601 n = BN_new();
602 if (!big1 || !big2 || !big32 || !r || !r_squared || !tmp || !big2_32 ||
603 !n) {
604 fprintf(stderr, "Out of memory (bignum)\n");
605 return -ENOMEM;
606 }
607
608 if (0 != rsa_get_exponent(key, exponent))
609 ret = -1;
610
611 RSA_get0_key(key, &key_n, NULL, NULL);
612 if (!BN_copy(n, key_n) || !BN_set_word(big1, 1L) ||
613 !BN_set_word(big2, 2L) || !BN_set_word(big32, 32L))
614 ret = -1;
615
616 /* big2_32 = 2^32 */
617 if (!BN_exp(big2_32, big2, big32, bn_ctx))
618 ret = -1;
619
620 /* Calculate n0_inv = -1 / n[0] mod 2^32 */
621 if (!BN_mod_inverse(tmp, n, big2_32, bn_ctx) ||
622 !BN_sub(tmp, big2_32, tmp))
623 ret = -1;
624 *n0_invp = BN_get_word(tmp);
625
626 /* Calculate R = 2^(# of key bits) */
627 if (!BN_set_word(tmp, BN_num_bits(n)) ||
628 !BN_exp(r, big2, tmp, bn_ctx))
629 ret = -1;
630
631 /* Calculate r_squared = R^2 mod n */
632 if (!BN_copy(r_squared, r) ||
633 !BN_mul(tmp, r_squared, r, bn_ctx) ||
634 !BN_mod(r_squared, tmp, n, bn_ctx))
635 ret = -1;
636
637 *modulusp = n;
638 *r_squaredp = r_squared;
639
640 BN_free(big1);
641 BN_free(big2);
642 BN_free(big32);
643 BN_free(r);
644 BN_free(tmp);
645 BN_free(big2_32);
646 if (ret) {
647 fprintf(stderr, "Bignum operations failed\n");
648 return -ENOMEM;
649 }
650
651 return ret;
652 }
653
fdt_add_bignum(void * blob,int noffset,const char * prop_name,BIGNUM * num,int num_bits)654 static int fdt_add_bignum(void *blob, int noffset, const char *prop_name,
655 BIGNUM *num, int num_bits)
656 {
657 int nwords = num_bits / 32;
658 int size;
659 uint32_t *buf, *ptr;
660 BIGNUM *tmp, *big2, *big32, *big2_32;
661 BN_CTX *ctx;
662 int ret;
663
664 tmp = BN_new();
665 big2 = BN_new();
666 big32 = BN_new();
667 big2_32 = BN_new();
668
669 /*
670 * Note: This code assumes that all of the above succeed, or all fail.
671 * In practice memory allocations generally do not fail (unless the
672 * process is killed), so it does not seem worth handling each of these
673 * as a separate case. Technicaly this could leak memory on failure,
674 * but a) it won't happen in practice, and b) it doesn't matter as we
675 * will immediately exit with a failure code.
676 */
677 if (!tmp || !big2 || !big32 || !big2_32) {
678 fprintf(stderr, "Out of memory (bignum)\n");
679 return -ENOMEM;
680 }
681 ctx = BN_CTX_new();
682 if (!tmp) {
683 fprintf(stderr, "Out of memory (bignum context)\n");
684 return -ENOMEM;
685 }
686 BN_set_word(big2, 2L);
687 BN_set_word(big32, 32L);
688 BN_exp(big2_32, big2, big32, ctx); /* B = 2^32 */
689
690 size = nwords * sizeof(uint32_t);
691 buf = malloc(size);
692 if (!buf) {
693 fprintf(stderr, "Out of memory (%d bytes)\n", size);
694 return -ENOMEM;
695 }
696
697 /* Write out modulus as big endian array of integers */
698 for (ptr = buf + nwords - 1; ptr >= buf; ptr--) {
699 BN_mod(tmp, num, big2_32, ctx); /* n = N mod B */
700 *ptr = cpu_to_fdt32(BN_get_word(tmp));
701 BN_rshift(num, num, 32); /* N = N/B */
702 }
703
704 /*
705 * We try signing with successively increasing size values, so this
706 * might fail several times
707 */
708 ret = fdt_setprop(blob, noffset, prop_name, buf, size);
709 free(buf);
710 BN_free(tmp);
711 BN_free(big2);
712 BN_free(big32);
713 BN_free(big2_32);
714
715 return ret ? -FDT_ERR_NOSPACE : 0;
716 }
717
rsa_add_verify_data(struct image_sign_info * info,void * keydest)718 int rsa_add_verify_data(struct image_sign_info *info, void *keydest)
719 {
720 BIGNUM *modulus, *r_squared;
721 uint64_t exponent;
722 uint32_t n0_inv;
723 int parent, node;
724 char name[100];
725 int ret;
726 int bits;
727 RSA *rsa;
728 ENGINE *e = NULL;
729
730 debug("%s: Getting verification data\n", __func__);
731 if (info->engine_id) {
732 ret = rsa_engine_init(info->engine_id, &e);
733 if (ret)
734 return ret;
735 }
736 ret = rsa_get_pub_key(info->keydir, info->keyname, e, &rsa);
737 if (ret)
738 goto err_get_pub_key;
739 ret = rsa_get_params(rsa, &exponent, &n0_inv, &modulus, &r_squared);
740 if (ret)
741 goto err_get_params;
742 bits = BN_num_bits(modulus);
743 parent = fdt_subnode_offset(keydest, 0, FIT_SIG_NODENAME);
744 if (parent == -FDT_ERR_NOTFOUND) {
745 parent = fdt_add_subnode(keydest, 0, FIT_SIG_NODENAME);
746 if (parent < 0) {
747 ret = parent;
748 if (ret != -FDT_ERR_NOSPACE) {
749 fprintf(stderr, "Couldn't create signature node: %s\n",
750 fdt_strerror(parent));
751 }
752 }
753 }
754 if (ret)
755 goto done;
756
757 /* Either create or overwrite the named key node */
758 snprintf(name, sizeof(name), "key-%s", info->keyname);
759 node = fdt_subnode_offset(keydest, parent, name);
760 if (node == -FDT_ERR_NOTFOUND) {
761 node = fdt_add_subnode(keydest, parent, name);
762 if (node < 0) {
763 ret = node;
764 if (ret != -FDT_ERR_NOSPACE) {
765 fprintf(stderr, "Could not create key subnode: %s\n",
766 fdt_strerror(node));
767 }
768 }
769 } else if (node < 0) {
770 fprintf(stderr, "Cannot select keys parent: %s\n",
771 fdt_strerror(node));
772 ret = node;
773 }
774
775 if (!ret) {
776 ret = fdt_setprop_string(keydest, node, "key-name-hint",
777 info->keyname);
778 }
779 if (!ret)
780 ret = fdt_setprop_u32(keydest, node, "rsa,num-bits", bits);
781 if (!ret)
782 ret = fdt_setprop_u32(keydest, node, "rsa,n0-inverse", n0_inv);
783 if (!ret) {
784 ret = fdt_setprop_u64(keydest, node, "rsa,exponent", exponent);
785 }
786 if (!ret) {
787 ret = fdt_add_bignum(keydest, node, "rsa,modulus", modulus,
788 bits);
789 }
790 if (!ret) {
791 ret = fdt_add_bignum(keydest, node, "rsa,r-squared", r_squared,
792 bits);
793 }
794 if (!ret) {
795 ret = fdt_setprop_string(keydest, node, FIT_ALGO_PROP,
796 info->name);
797 }
798 if (!ret && info->require_keys) {
799 ret = fdt_setprop_string(keydest, node, "required",
800 info->require_keys);
801 }
802 done:
803 BN_free(modulus);
804 BN_free(r_squared);
805 if (ret)
806 ret = ret == -FDT_ERR_NOSPACE ? -ENOSPC : -EIO;
807 err_get_params:
808 RSA_free(rsa);
809 err_get_pub_key:
810 if (info->engine_id)
811 rsa_engine_remove(e);
812
813 return ret;
814 }
815