/src/openssl/crypto/rsa/rsa_ossl.c
Line | Count | Source (jump to first uncovered line) |
1 | | /* |
2 | | * Copyright 1995-2022 The OpenSSL Project Authors. All Rights Reserved. |
3 | | * |
4 | | * Licensed under the Apache License 2.0 (the "License"). You may not use |
5 | | * this file except in compliance with the License. You can obtain a copy |
6 | | * in the file LICENSE in the source distribution or at |
7 | | * https://www.openssl.org/source/license.html |
8 | | */ |
9 | | |
10 | | /* |
11 | | * RSA low level APIs are deprecated for public use, but still ok for |
12 | | * internal use. |
13 | | */ |
14 | | #include "internal/deprecated.h" |
15 | | |
16 | | #include "internal/cryptlib.h" |
17 | | #include "crypto/bn.h" |
18 | | #include "rsa_local.h" |
19 | | #include "internal/constant_time.h" |
20 | | #include <openssl/evp.h> |
21 | | #include <openssl/sha.h> |
22 | | #include <openssl/hmac.h> |
23 | | |
24 | | static int rsa_ossl_public_encrypt(int flen, const unsigned char *from, |
25 | | unsigned char *to, RSA *rsa, int padding); |
26 | | static int rsa_ossl_private_encrypt(int flen, const unsigned char *from, |
27 | | unsigned char *to, RSA *rsa, int padding); |
28 | | static int rsa_ossl_public_decrypt(int flen, const unsigned char *from, |
29 | | unsigned char *to, RSA *rsa, int padding); |
30 | | static int rsa_ossl_private_decrypt(int flen, const unsigned char *from, |
31 | | unsigned char *to, RSA *rsa, int padding); |
32 | | static int rsa_ossl_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa, |
33 | | BN_CTX *ctx); |
34 | | static int rsa_ossl_init(RSA *rsa); |
35 | | static int rsa_ossl_finish(RSA *rsa); |
36 | | #ifdef S390X_MOD_EXP |
37 | | static int rsa_ossl_s390x_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa, |
38 | | BN_CTX *ctx); |
39 | | static RSA_METHOD rsa_pkcs1_ossl_meth = { |
40 | | "OpenSSL PKCS#1 RSA", |
41 | | rsa_ossl_public_encrypt, |
42 | | rsa_ossl_public_decrypt, /* signature verification */ |
43 | | rsa_ossl_private_encrypt, /* signing */ |
44 | | rsa_ossl_private_decrypt, |
45 | | rsa_ossl_s390x_mod_exp, |
46 | | s390x_mod_exp, |
47 | | rsa_ossl_init, |
48 | | rsa_ossl_finish, |
49 | | RSA_FLAG_FIPS_METHOD, /* flags */ |
50 | | NULL, |
51 | | 0, /* rsa_sign */ |
52 | | 0, /* rsa_verify */ |
53 | | NULL, /* rsa_keygen */ |
54 | | NULL /* rsa_multi_prime_keygen */ |
55 | | }; |
56 | | #else |
57 | | static RSA_METHOD rsa_pkcs1_ossl_meth = { |
58 | | "OpenSSL PKCS#1 RSA", |
59 | | rsa_ossl_public_encrypt, |
60 | | rsa_ossl_public_decrypt, /* signature verification */ |
61 | | rsa_ossl_private_encrypt, /* signing */ |
62 | | rsa_ossl_private_decrypt, |
63 | | rsa_ossl_mod_exp, |
64 | | BN_mod_exp_mont, /* XXX probably we should not use Montgomery |
65 | | * if e == 3 */ |
66 | | rsa_ossl_init, |
67 | | rsa_ossl_finish, |
68 | | RSA_FLAG_FIPS_METHOD, /* flags */ |
69 | | NULL, |
70 | | 0, /* rsa_sign */ |
71 | | 0, /* rsa_verify */ |
72 | | NULL, /* rsa_keygen */ |
73 | | NULL /* rsa_multi_prime_keygen */ |
74 | | }; |
75 | | #endif |
76 | | |
77 | | static const RSA_METHOD *default_RSA_meth = &rsa_pkcs1_ossl_meth; |
78 | | |
79 | | void RSA_set_default_method(const RSA_METHOD *meth) |
80 | 0 | { |
81 | 0 | default_RSA_meth = meth; |
82 | 0 | } |
83 | | |
84 | | const RSA_METHOD *RSA_get_default_method(void) |
85 | 9.53k | { |
86 | 9.53k | return default_RSA_meth; |
87 | 9.53k | } |
88 | | |
89 | | const RSA_METHOD *RSA_PKCS1_OpenSSL(void) |
90 | 0 | { |
91 | 0 | return &rsa_pkcs1_ossl_meth; |
92 | 0 | } |
93 | | |
94 | | const RSA_METHOD *RSA_null_method(void) |
95 | 0 | { |
96 | 0 | return NULL; |
97 | 0 | } |
98 | | |
99 | | static int rsa_ossl_public_encrypt(int flen, const unsigned char *from, |
100 | | unsigned char *to, RSA *rsa, int padding) |
101 | 0 | { |
102 | 0 | BIGNUM *f, *ret; |
103 | 0 | int i, num = 0, r = -1; |
104 | 0 | unsigned char *buf = NULL; |
105 | 0 | BN_CTX *ctx = NULL; |
106 | |
|
107 | 0 | if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS) { |
108 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_MODULUS_TOO_LARGE); |
109 | 0 | return -1; |
110 | 0 | } |
111 | | |
112 | 0 | if (BN_ucmp(rsa->n, rsa->e) <= 0) { |
113 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_BAD_E_VALUE); |
114 | 0 | return -1; |
115 | 0 | } |
116 | | |
117 | | /* for large moduli, enforce exponent limit */ |
118 | 0 | if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS) { |
119 | 0 | if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS) { |
120 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_BAD_E_VALUE); |
121 | 0 | return -1; |
122 | 0 | } |
123 | 0 | } |
124 | | |
125 | 0 | if ((ctx = BN_CTX_new_ex(rsa->libctx)) == NULL) |
126 | 0 | goto err; |
127 | 0 | BN_CTX_start(ctx); |
128 | 0 | f = BN_CTX_get(ctx); |
129 | 0 | ret = BN_CTX_get(ctx); |
130 | 0 | num = BN_num_bytes(rsa->n); |
131 | 0 | buf = OPENSSL_malloc(num); |
132 | 0 | if (ret == NULL || buf == NULL) |
133 | 0 | goto err; |
134 | | |
135 | 0 | switch (padding) { |
136 | 0 | case RSA_PKCS1_PADDING: |
137 | 0 | i = ossl_rsa_padding_add_PKCS1_type_2_ex(rsa->libctx, buf, num, |
138 | 0 | from, flen); |
139 | 0 | break; |
140 | 0 | case RSA_PKCS1_OAEP_PADDING: |
141 | 0 | i = ossl_rsa_padding_add_PKCS1_OAEP_mgf1_ex(rsa->libctx, buf, num, |
142 | 0 | from, flen, NULL, 0, |
143 | 0 | NULL, NULL); |
144 | 0 | break; |
145 | 0 | case RSA_NO_PADDING: |
146 | 0 | i = RSA_padding_add_none(buf, num, from, flen); |
147 | 0 | break; |
148 | 0 | default: |
149 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_UNKNOWN_PADDING_TYPE); |
150 | 0 | goto err; |
151 | 0 | } |
152 | 0 | if (i <= 0) |
153 | 0 | goto err; |
154 | | |
155 | 0 | if (BN_bin2bn(buf, num, f) == NULL) |
156 | 0 | goto err; |
157 | | |
158 | 0 | if (BN_ucmp(f, rsa->n) >= 0) { |
159 | | /* usually the padding functions would catch this */ |
160 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_DATA_TOO_LARGE_FOR_MODULUS); |
161 | 0 | goto err; |
162 | 0 | } |
163 | | |
164 | 0 | if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) |
165 | 0 | if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n, rsa->lock, |
166 | 0 | rsa->n, ctx)) |
167 | 0 | goto err; |
168 | | |
169 | 0 | if (!rsa->meth->bn_mod_exp(ret, f, rsa->e, rsa->n, ctx, |
170 | 0 | rsa->_method_mod_n)) |
171 | 0 | goto err; |
172 | | |
173 | | /* |
174 | | * BN_bn2binpad puts in leading 0 bytes if the number is less than |
175 | | * the length of the modulus. |
176 | | */ |
177 | 0 | r = BN_bn2binpad(ret, to, num); |
178 | 0 | err: |
179 | 0 | BN_CTX_end(ctx); |
180 | 0 | BN_CTX_free(ctx); |
181 | 0 | OPENSSL_clear_free(buf, num); |
182 | 0 | return r; |
183 | 0 | } |
184 | | |
185 | | static BN_BLINDING *rsa_get_blinding(RSA *rsa, int *local, BN_CTX *ctx) |
186 | 0 | { |
187 | 0 | BN_BLINDING *ret; |
188 | |
|
189 | 0 | if (!CRYPTO_THREAD_read_lock(rsa->lock)) |
190 | 0 | return NULL; |
191 | | |
192 | 0 | if (rsa->blinding == NULL) { |
193 | | /* |
194 | | * This dance with upgrading the lock from read to write will be |
195 | | * slower in cases of a single use RSA object, but should be |
196 | | * significantly better in multi-thread cases (e.g. servers). It's |
197 | | * probably worth it. |
198 | | */ |
199 | 0 | CRYPTO_THREAD_unlock(rsa->lock); |
200 | 0 | if (!CRYPTO_THREAD_write_lock(rsa->lock)) |
201 | 0 | return NULL; |
202 | 0 | if (rsa->blinding == NULL) |
203 | 0 | rsa->blinding = RSA_setup_blinding(rsa, ctx); |
204 | 0 | } |
205 | | |
206 | 0 | ret = rsa->blinding; |
207 | 0 | if (ret == NULL) |
208 | 0 | goto err; |
209 | | |
210 | 0 | if (BN_BLINDING_is_current_thread(ret)) { |
211 | | /* rsa->blinding is ours! */ |
212 | |
|
213 | 0 | *local = 1; |
214 | 0 | } else { |
215 | | /* resort to rsa->mt_blinding instead */ |
216 | | |
217 | | /* |
218 | | * instructs rsa_blinding_convert(), rsa_blinding_invert() that the |
219 | | * BN_BLINDING is shared, meaning that accesses require locks, and |
220 | | * that the blinding factor must be stored outside the BN_BLINDING |
221 | | */ |
222 | 0 | *local = 0; |
223 | |
|
224 | 0 | if (rsa->mt_blinding == NULL) { |
225 | 0 | CRYPTO_THREAD_unlock(rsa->lock); |
226 | 0 | if (!CRYPTO_THREAD_write_lock(rsa->lock)) |
227 | 0 | return NULL; |
228 | 0 | if (rsa->mt_blinding == NULL) |
229 | 0 | rsa->mt_blinding = RSA_setup_blinding(rsa, ctx); |
230 | 0 | } |
231 | 0 | ret = rsa->mt_blinding; |
232 | 0 | } |
233 | | |
234 | 0 | err: |
235 | 0 | CRYPTO_THREAD_unlock(rsa->lock); |
236 | 0 | return ret; |
237 | 0 | } |
238 | | |
239 | | static int rsa_blinding_convert(BN_BLINDING *b, BIGNUM *f, BIGNUM *unblind, |
240 | | BN_CTX *ctx) |
241 | 0 | { |
242 | 0 | if (unblind == NULL) { |
243 | | /* |
244 | | * Local blinding: store the unblinding factor in BN_BLINDING. |
245 | | */ |
246 | 0 | return BN_BLINDING_convert_ex(f, NULL, b, ctx); |
247 | 0 | } else { |
248 | | /* |
249 | | * Shared blinding: store the unblinding factor outside BN_BLINDING. |
250 | | */ |
251 | 0 | int ret; |
252 | |
|
253 | 0 | if (!BN_BLINDING_lock(b)) |
254 | 0 | return 0; |
255 | | |
256 | 0 | ret = BN_BLINDING_convert_ex(f, unblind, b, ctx); |
257 | 0 | BN_BLINDING_unlock(b); |
258 | |
|
259 | 0 | return ret; |
260 | 0 | } |
261 | 0 | } |
262 | | |
263 | | static int rsa_blinding_invert(BN_BLINDING *b, BIGNUM *f, BIGNUM *unblind, |
264 | | BN_CTX *ctx) |
265 | 0 | { |
266 | | /* |
267 | | * For local blinding, unblind is set to NULL, and BN_BLINDING_invert_ex |
268 | | * will use the unblinding factor stored in BN_BLINDING. If BN_BLINDING |
269 | | * is shared between threads, unblind must be non-null: |
270 | | * BN_BLINDING_invert_ex will then use the local unblinding factor, and |
271 | | * will only read the modulus from BN_BLINDING. In both cases it's safe |
272 | | * to access the blinding without a lock. |
273 | | */ |
274 | 0 | BN_set_flags(f, BN_FLG_CONSTTIME); |
275 | 0 | return BN_BLINDING_invert_ex(f, unblind, b, ctx); |
276 | 0 | } |
277 | | |
278 | | /* signing */ |
279 | | static int rsa_ossl_private_encrypt(int flen, const unsigned char *from, |
280 | | unsigned char *to, RSA *rsa, int padding) |
281 | 0 | { |
282 | 0 | BIGNUM *f, *ret, *res; |
283 | 0 | int i, num = 0, r = -1; |
284 | 0 | unsigned char *buf = NULL; |
285 | 0 | BN_CTX *ctx = NULL; |
286 | 0 | int local_blinding = 0; |
287 | | /* |
288 | | * Used only if the blinding structure is shared. A non-NULL unblind |
289 | | * instructs rsa_blinding_convert() and rsa_blinding_invert() to store |
290 | | * the unblinding factor outside the blinding structure. |
291 | | */ |
292 | 0 | BIGNUM *unblind = NULL; |
293 | 0 | BN_BLINDING *blinding = NULL; |
294 | |
|
295 | 0 | if ((ctx = BN_CTX_new_ex(rsa->libctx)) == NULL) |
296 | 0 | goto err; |
297 | 0 | BN_CTX_start(ctx); |
298 | 0 | f = BN_CTX_get(ctx); |
299 | 0 | ret = BN_CTX_get(ctx); |
300 | 0 | num = BN_num_bytes(rsa->n); |
301 | 0 | buf = OPENSSL_malloc(num); |
302 | 0 | if (ret == NULL || buf == NULL) |
303 | 0 | goto err; |
304 | | |
305 | 0 | switch (padding) { |
306 | 0 | case RSA_PKCS1_PADDING: |
307 | 0 | i = RSA_padding_add_PKCS1_type_1(buf, num, from, flen); |
308 | 0 | break; |
309 | 0 | case RSA_X931_PADDING: |
310 | 0 | i = RSA_padding_add_X931(buf, num, from, flen); |
311 | 0 | break; |
312 | 0 | case RSA_NO_PADDING: |
313 | 0 | i = RSA_padding_add_none(buf, num, from, flen); |
314 | 0 | break; |
315 | 0 | default: |
316 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_UNKNOWN_PADDING_TYPE); |
317 | 0 | goto err; |
318 | 0 | } |
319 | 0 | if (i <= 0) |
320 | 0 | goto err; |
321 | | |
322 | 0 | if (BN_bin2bn(buf, num, f) == NULL) |
323 | 0 | goto err; |
324 | | |
325 | 0 | if (BN_ucmp(f, rsa->n) >= 0) { |
326 | | /* usually the padding functions would catch this */ |
327 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_DATA_TOO_LARGE_FOR_MODULUS); |
328 | 0 | goto err; |
329 | 0 | } |
330 | | |
331 | 0 | if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) |
332 | 0 | if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n, rsa->lock, |
333 | 0 | rsa->n, ctx)) |
334 | 0 | goto err; |
335 | | |
336 | 0 | if (!(rsa->flags & RSA_FLAG_NO_BLINDING)) { |
337 | 0 | blinding = rsa_get_blinding(rsa, &local_blinding, ctx); |
338 | 0 | if (blinding == NULL) { |
339 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_INTERNAL_ERROR); |
340 | 0 | goto err; |
341 | 0 | } |
342 | 0 | } |
343 | | |
344 | 0 | if (blinding != NULL) { |
345 | 0 | if (!local_blinding && ((unblind = BN_CTX_get(ctx)) == NULL)) { |
346 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_BN_LIB); |
347 | 0 | goto err; |
348 | 0 | } |
349 | 0 | if (!rsa_blinding_convert(blinding, f, unblind, ctx)) |
350 | 0 | goto err; |
351 | 0 | } |
352 | | |
353 | 0 | if ((rsa->flags & RSA_FLAG_EXT_PKEY) || |
354 | 0 | (rsa->version == RSA_ASN1_VERSION_MULTI) || |
355 | 0 | ((rsa->p != NULL) && |
356 | 0 | (rsa->q != NULL) && |
357 | 0 | (rsa->dmp1 != NULL) && (rsa->dmq1 != NULL) && (rsa->iqmp != NULL))) { |
358 | 0 | if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) |
359 | 0 | goto err; |
360 | 0 | } else { |
361 | 0 | BIGNUM *d = BN_new(); |
362 | 0 | if (d == NULL) { |
363 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_BN_LIB); |
364 | 0 | goto err; |
365 | 0 | } |
366 | 0 | if (rsa->d == NULL) { |
367 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_MISSING_PRIVATE_KEY); |
368 | 0 | BN_free(d); |
369 | 0 | goto err; |
370 | 0 | } |
371 | 0 | BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME); |
372 | |
|
373 | 0 | if (!rsa->meth->bn_mod_exp(ret, f, d, rsa->n, ctx, |
374 | 0 | rsa->_method_mod_n)) { |
375 | 0 | BN_free(d); |
376 | 0 | goto err; |
377 | 0 | } |
378 | | /* We MUST free d before any further use of rsa->d */ |
379 | 0 | BN_free(d); |
380 | 0 | } |
381 | | |
382 | 0 | if (blinding) |
383 | 0 | if (!rsa_blinding_invert(blinding, ret, unblind, ctx)) |
384 | 0 | goto err; |
385 | | |
386 | 0 | if (padding == RSA_X931_PADDING) { |
387 | 0 | if (!BN_sub(f, rsa->n, ret)) |
388 | 0 | goto err; |
389 | 0 | if (BN_cmp(ret, f) > 0) |
390 | 0 | res = f; |
391 | 0 | else |
392 | 0 | res = ret; |
393 | 0 | } else { |
394 | 0 | res = ret; |
395 | 0 | } |
396 | | |
397 | | /* |
398 | | * BN_bn2binpad puts in leading 0 bytes if the number is less than |
399 | | * the length of the modulus. |
400 | | */ |
401 | 0 | r = BN_bn2binpad(res, to, num); |
402 | 0 | err: |
403 | 0 | BN_CTX_end(ctx); |
404 | 0 | BN_CTX_free(ctx); |
405 | 0 | OPENSSL_clear_free(buf, num); |
406 | 0 | return r; |
407 | 0 | } |
408 | | |
409 | | static int derive_kdk(int flen, const unsigned char *from, RSA *rsa, |
410 | | unsigned char *buf, int num, unsigned char *kdk) |
411 | 0 | { |
412 | 0 | int ret = 0; |
413 | 0 | HMAC_CTX *hmac = NULL; |
414 | 0 | EVP_MD *md = NULL; |
415 | 0 | unsigned int md_len = SHA256_DIGEST_LENGTH; |
416 | 0 | unsigned char d_hash[SHA256_DIGEST_LENGTH] = {0}; |
417 | | /* |
418 | | * because we use d as a handle to rsa->d we need to keep it local and |
419 | | * free before any further use of rsa->d |
420 | | */ |
421 | 0 | BIGNUM *d = BN_new(); |
422 | |
|
423 | 0 | if (d == NULL) { |
424 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_CRYPTO_LIB); |
425 | 0 | goto err; |
426 | 0 | } |
427 | 0 | if (rsa->d == NULL) { |
428 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_MISSING_PRIVATE_KEY); |
429 | 0 | BN_free(d); |
430 | 0 | goto err; |
431 | 0 | } |
432 | 0 | BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME); |
433 | 0 | if (BN_bn2binpad(d, buf, num) < 0) { |
434 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_INTERNAL_ERROR); |
435 | 0 | BN_free(d); |
436 | 0 | goto err; |
437 | 0 | } |
438 | 0 | BN_free(d); |
439 | | |
440 | | /* |
441 | | * we use hardcoded hash so that migrating between versions that use |
442 | | * different hash doesn't provide a Bleichenbacher oracle: |
443 | | * if the attacker can see that different versions return different |
444 | | * messages for the same ciphertext, they'll know that the message is |
445 | | * syntethically generated, which means that the padding check failed |
446 | | */ |
447 | 0 | md = EVP_MD_fetch(rsa->libctx, "sha256", NULL); |
448 | 0 | if (md == NULL) { |
449 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_FETCH_FAILED); |
450 | 0 | goto err; |
451 | 0 | } |
452 | | |
453 | 0 | if (EVP_Digest(buf, num, d_hash, NULL, md, NULL) <= 0) { |
454 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_INTERNAL_ERROR); |
455 | 0 | goto err; |
456 | 0 | } |
457 | | |
458 | 0 | hmac = HMAC_CTX_new(); |
459 | 0 | if (hmac == NULL) { |
460 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_CRYPTO_LIB); |
461 | 0 | goto err; |
462 | 0 | } |
463 | | |
464 | 0 | if (HMAC_Init_ex(hmac, d_hash, sizeof(d_hash), md, NULL) <= 0) { |
465 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_INTERNAL_ERROR); |
466 | 0 | goto err; |
467 | 0 | } |
468 | | |
469 | 0 | if (flen < num) { |
470 | 0 | memset(buf, 0, num - flen); |
471 | 0 | if (HMAC_Update(hmac, buf, num - flen) <= 0) { |
472 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_INTERNAL_ERROR); |
473 | 0 | goto err; |
474 | 0 | } |
475 | 0 | } |
476 | 0 | if (HMAC_Update(hmac, from, flen) <= 0) { |
477 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_INTERNAL_ERROR); |
478 | 0 | goto err; |
479 | 0 | } |
480 | | |
481 | 0 | md_len = SHA256_DIGEST_LENGTH; |
482 | 0 | if (HMAC_Final(hmac, kdk, &md_len) <= 0) { |
483 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_INTERNAL_ERROR); |
484 | 0 | goto err; |
485 | 0 | } |
486 | 0 | ret = 1; |
487 | |
|
488 | 0 | err: |
489 | 0 | HMAC_CTX_free(hmac); |
490 | 0 | EVP_MD_free(md); |
491 | 0 | return ret; |
492 | 0 | } |
493 | | |
494 | | static int rsa_ossl_private_decrypt(int flen, const unsigned char *from, |
495 | | unsigned char *to, RSA *rsa, int padding) |
496 | 0 | { |
497 | 0 | BIGNUM *f, *ret; |
498 | 0 | int j, num = 0, r = -1; |
499 | 0 | unsigned char *buf = NULL; |
500 | 0 | unsigned char kdk[SHA256_DIGEST_LENGTH] = {0}; |
501 | 0 | BN_CTX *ctx = NULL; |
502 | 0 | int local_blinding = 0; |
503 | | /* |
504 | | * Used only if the blinding structure is shared. A non-NULL unblind |
505 | | * instructs rsa_blinding_convert() and rsa_blinding_invert() to store |
506 | | * the unblinding factor outside the blinding structure. |
507 | | */ |
508 | 0 | BIGNUM *unblind = NULL; |
509 | 0 | BN_BLINDING *blinding = NULL; |
510 | | |
511 | | /* |
512 | | * we need the value of the private exponent to perform implicit rejection |
513 | | */ |
514 | 0 | if ((rsa->flags & RSA_FLAG_EXT_PKEY) && (padding == RSA_PKCS1_PADDING)) |
515 | 0 | padding = RSA_PKCS1_NO_IMPLICIT_REJECT_PADDING; |
516 | |
|
517 | 0 | if ((ctx = BN_CTX_new_ex(rsa->libctx)) == NULL) |
518 | 0 | goto err; |
519 | 0 | BN_CTX_start(ctx); |
520 | 0 | f = BN_CTX_get(ctx); |
521 | 0 | ret = BN_CTX_get(ctx); |
522 | 0 | if (ret == NULL) { |
523 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_BN_LIB); |
524 | 0 | goto err; |
525 | 0 | } |
526 | 0 | num = BN_num_bytes(rsa->n); |
527 | 0 | buf = OPENSSL_malloc(num); |
528 | 0 | if (buf == NULL) |
529 | 0 | goto err; |
530 | | |
531 | | /* |
532 | | * This check was for equality but PGP does evil things and chops off the |
533 | | * top '0' bytes |
534 | | */ |
535 | 0 | if (flen > num) { |
536 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_DATA_GREATER_THAN_MOD_LEN); |
537 | 0 | goto err; |
538 | 0 | } |
539 | | |
540 | 0 | if (flen < 1) { |
541 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_DATA_TOO_SMALL); |
542 | 0 | goto err; |
543 | 0 | } |
544 | | |
545 | | /* make data into a big number */ |
546 | 0 | if (BN_bin2bn(from, (int)flen, f) == NULL) |
547 | 0 | goto err; |
548 | | |
549 | 0 | if (BN_ucmp(f, rsa->n) >= 0) { |
550 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_DATA_TOO_LARGE_FOR_MODULUS); |
551 | 0 | goto err; |
552 | 0 | } |
553 | | |
554 | 0 | if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) |
555 | 0 | if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n, rsa->lock, |
556 | 0 | rsa->n, ctx)) |
557 | 0 | goto err; |
558 | | |
559 | 0 | if (!(rsa->flags & RSA_FLAG_NO_BLINDING)) { |
560 | 0 | blinding = rsa_get_blinding(rsa, &local_blinding, ctx); |
561 | 0 | if (blinding == NULL) { |
562 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_INTERNAL_ERROR); |
563 | 0 | goto err; |
564 | 0 | } |
565 | 0 | } |
566 | | |
567 | 0 | if (blinding != NULL) { |
568 | 0 | if (!local_blinding && ((unblind = BN_CTX_get(ctx)) == NULL)) { |
569 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_BN_LIB); |
570 | 0 | goto err; |
571 | 0 | } |
572 | 0 | if (!rsa_blinding_convert(blinding, f, unblind, ctx)) |
573 | 0 | goto err; |
574 | 0 | } |
575 | | |
576 | | /* do the decrypt */ |
577 | 0 | if ((rsa->flags & RSA_FLAG_EXT_PKEY) || |
578 | 0 | (rsa->version == RSA_ASN1_VERSION_MULTI) || |
579 | 0 | ((rsa->p != NULL) && |
580 | 0 | (rsa->q != NULL) && |
581 | 0 | (rsa->dmp1 != NULL) && (rsa->dmq1 != NULL) && (rsa->iqmp != NULL))) { |
582 | 0 | if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) |
583 | 0 | goto err; |
584 | 0 | } else { |
585 | 0 | BIGNUM *d = BN_new(); |
586 | 0 | if (d == NULL) { |
587 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_BN_LIB); |
588 | 0 | goto err; |
589 | 0 | } |
590 | 0 | if (rsa->d == NULL) { |
591 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_MISSING_PRIVATE_KEY); |
592 | 0 | BN_free(d); |
593 | 0 | goto err; |
594 | 0 | } |
595 | 0 | BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME); |
596 | 0 | if (!rsa->meth->bn_mod_exp(ret, f, d, rsa->n, ctx, |
597 | 0 | rsa->_method_mod_n)) { |
598 | 0 | BN_free(d); |
599 | 0 | goto err; |
600 | 0 | } |
601 | | /* We MUST free d before any further use of rsa->d */ |
602 | 0 | BN_free(d); |
603 | 0 | } |
604 | | |
605 | 0 | if (blinding) |
606 | 0 | if (!rsa_blinding_invert(blinding, ret, unblind, ctx)) |
607 | 0 | goto err; |
608 | | |
609 | | /* |
610 | | * derive the Key Derivation Key from private exponent and public |
611 | | * ciphertext |
612 | | */ |
613 | 0 | if (padding == RSA_PKCS1_PADDING) { |
614 | 0 | if (derive_kdk(flen, from, rsa, buf, num, kdk) == 0) |
615 | 0 | goto err; |
616 | 0 | } |
617 | | |
618 | 0 | j = BN_bn2binpad(ret, buf, num); |
619 | 0 | if (j < 0) |
620 | 0 | goto err; |
621 | | |
622 | 0 | switch (padding) { |
623 | 0 | case RSA_PKCS1_NO_IMPLICIT_REJECT_PADDING: |
624 | 0 | r = RSA_padding_check_PKCS1_type_2(to, num, buf, j, num); |
625 | 0 | break; |
626 | 0 | case RSA_PKCS1_PADDING: |
627 | 0 | r = ossl_rsa_padding_check_PKCS1_type_2(rsa->libctx, to, num, buf, j, num, kdk); |
628 | 0 | break; |
629 | 0 | case RSA_PKCS1_OAEP_PADDING: |
630 | 0 | r = RSA_padding_check_PKCS1_OAEP(to, num, buf, j, num, NULL, 0); |
631 | 0 | break; |
632 | 0 | case RSA_NO_PADDING: |
633 | 0 | memcpy(to, buf, (r = j)); |
634 | 0 | break; |
635 | 0 | default: |
636 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_UNKNOWN_PADDING_TYPE); |
637 | 0 | goto err; |
638 | 0 | } |
639 | 0 | #ifndef FIPS_MODULE |
640 | | /* |
641 | | * This trick doesn't work in the FIPS provider because libcrypto manages |
642 | | * the error stack. Instead we opt not to put an error on the stack at all |
643 | | * in case of padding failure in the FIPS provider. |
644 | | */ |
645 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_PADDING_CHECK_FAILED); |
646 | 0 | err_clear_last_constant_time(1 & ~constant_time_msb(r)); |
647 | 0 | #endif |
648 | |
|
649 | 0 | err: |
650 | 0 | BN_CTX_end(ctx); |
651 | 0 | BN_CTX_free(ctx); |
652 | 0 | OPENSSL_clear_free(buf, num); |
653 | 0 | return r; |
654 | 0 | } |
655 | | |
656 | | /* signature verification */ |
657 | | static int rsa_ossl_public_decrypt(int flen, const unsigned char *from, |
658 | | unsigned char *to, RSA *rsa, int padding) |
659 | 0 | { |
660 | 0 | BIGNUM *f, *ret; |
661 | 0 | int i, num = 0, r = -1; |
662 | 0 | unsigned char *buf = NULL; |
663 | 0 | BN_CTX *ctx = NULL; |
664 | |
|
665 | 0 | if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS) { |
666 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_MODULUS_TOO_LARGE); |
667 | 0 | return -1; |
668 | 0 | } |
669 | | |
670 | 0 | if (BN_ucmp(rsa->n, rsa->e) <= 0) { |
671 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_BAD_E_VALUE); |
672 | 0 | return -1; |
673 | 0 | } |
674 | | |
675 | | /* for large moduli, enforce exponent limit */ |
676 | 0 | if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS) { |
677 | 0 | if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS) { |
678 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_BAD_E_VALUE); |
679 | 0 | return -1; |
680 | 0 | } |
681 | 0 | } |
682 | | |
683 | 0 | if ((ctx = BN_CTX_new_ex(rsa->libctx)) == NULL) |
684 | 0 | goto err; |
685 | 0 | BN_CTX_start(ctx); |
686 | 0 | f = BN_CTX_get(ctx); |
687 | 0 | ret = BN_CTX_get(ctx); |
688 | 0 | if (ret == NULL) { |
689 | 0 | ERR_raise(ERR_LIB_RSA, ERR_R_BN_LIB); |
690 | 0 | goto err; |
691 | 0 | } |
692 | 0 | num = BN_num_bytes(rsa->n); |
693 | 0 | buf = OPENSSL_malloc(num); |
694 | 0 | if (buf == NULL) |
695 | 0 | goto err; |
696 | | |
697 | | /* |
698 | | * This check was for equality but PGP does evil things and chops off the |
699 | | * top '0' bytes |
700 | | */ |
701 | 0 | if (flen > num) { |
702 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_DATA_GREATER_THAN_MOD_LEN); |
703 | 0 | goto err; |
704 | 0 | } |
705 | | |
706 | 0 | if (BN_bin2bn(from, flen, f) == NULL) |
707 | 0 | goto err; |
708 | | |
709 | 0 | if (BN_ucmp(f, rsa->n) >= 0) { |
710 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_DATA_TOO_LARGE_FOR_MODULUS); |
711 | 0 | goto err; |
712 | 0 | } |
713 | | |
714 | 0 | if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) |
715 | 0 | if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n, rsa->lock, |
716 | 0 | rsa->n, ctx)) |
717 | 0 | goto err; |
718 | | |
719 | 0 | if (!rsa->meth->bn_mod_exp(ret, f, rsa->e, rsa->n, ctx, |
720 | 0 | rsa->_method_mod_n)) |
721 | 0 | goto err; |
722 | | |
723 | 0 | if ((padding == RSA_X931_PADDING) && ((bn_get_words(ret)[0] & 0xf) != 12)) |
724 | 0 | if (!BN_sub(ret, rsa->n, ret)) |
725 | 0 | goto err; |
726 | | |
727 | 0 | i = BN_bn2binpad(ret, buf, num); |
728 | 0 | if (i < 0) |
729 | 0 | goto err; |
730 | | |
731 | 0 | switch (padding) { |
732 | 0 | case RSA_PKCS1_PADDING: |
733 | 0 | r = RSA_padding_check_PKCS1_type_1(to, num, buf, i, num); |
734 | 0 | break; |
735 | 0 | case RSA_X931_PADDING: |
736 | 0 | r = RSA_padding_check_X931(to, num, buf, i, num); |
737 | 0 | break; |
738 | 0 | case RSA_NO_PADDING: |
739 | 0 | memcpy(to, buf, (r = i)); |
740 | 0 | break; |
741 | 0 | default: |
742 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_UNKNOWN_PADDING_TYPE); |
743 | 0 | goto err; |
744 | 0 | } |
745 | 0 | if (r < 0) |
746 | 0 | ERR_raise(ERR_LIB_RSA, RSA_R_PADDING_CHECK_FAILED); |
747 | |
|
748 | 0 | err: |
749 | 0 | BN_CTX_end(ctx); |
750 | 0 | BN_CTX_free(ctx); |
751 | 0 | OPENSSL_clear_free(buf, num); |
752 | 0 | return r; |
753 | 0 | } |
754 | | |
755 | | static int rsa_ossl_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx) |
756 | 0 | { |
757 | 0 | BIGNUM *r1, *m1, *vrfy; |
758 | 0 | int ret = 0, smooth = 0; |
759 | 0 | #ifndef FIPS_MODULE |
760 | 0 | BIGNUM *r2, *m[RSA_MAX_PRIME_NUM - 2]; |
761 | 0 | int i, ex_primes = 0; |
762 | 0 | RSA_PRIME_INFO *pinfo; |
763 | 0 | #endif |
764 | |
|
765 | 0 | BN_CTX_start(ctx); |
766 | |
|
767 | 0 | r1 = BN_CTX_get(ctx); |
768 | 0 | #ifndef FIPS_MODULE |
769 | 0 | r2 = BN_CTX_get(ctx); |
770 | 0 | #endif |
771 | 0 | m1 = BN_CTX_get(ctx); |
772 | 0 | vrfy = BN_CTX_get(ctx); |
773 | 0 | if (vrfy == NULL) |
774 | 0 | goto err; |
775 | | |
776 | 0 | #ifndef FIPS_MODULE |
777 | 0 | if (rsa->version == RSA_ASN1_VERSION_MULTI |
778 | 0 | && ((ex_primes = sk_RSA_PRIME_INFO_num(rsa->prime_infos)) <= 0 |
779 | 0 | || ex_primes > RSA_MAX_PRIME_NUM - 2)) |
780 | 0 | goto err; |
781 | 0 | #endif |
782 | | |
783 | 0 | if (rsa->flags & RSA_FLAG_CACHE_PRIVATE) { |
784 | 0 | BIGNUM *factor = BN_new(); |
785 | |
|
786 | 0 | if (factor == NULL) |
787 | 0 | goto err; |
788 | | |
789 | | /* |
790 | | * Make sure BN_mod_inverse in Montgomery initialization uses the |
791 | | * BN_FLG_CONSTTIME flag |
792 | | */ |
793 | 0 | if (!(BN_with_flags(factor, rsa->p, BN_FLG_CONSTTIME), |
794 | 0 | BN_MONT_CTX_set_locked(&rsa->_method_mod_p, rsa->lock, |
795 | 0 | factor, ctx)) |
796 | 0 | || !(BN_with_flags(factor, rsa->q, BN_FLG_CONSTTIME), |
797 | 0 | BN_MONT_CTX_set_locked(&rsa->_method_mod_q, rsa->lock, |
798 | 0 | factor, ctx))) { |
799 | 0 | BN_free(factor); |
800 | 0 | goto err; |
801 | 0 | } |
802 | 0 | #ifndef FIPS_MODULE |
803 | 0 | for (i = 0; i < ex_primes; i++) { |
804 | 0 | pinfo = sk_RSA_PRIME_INFO_value(rsa->prime_infos, i); |
805 | 0 | BN_with_flags(factor, pinfo->r, BN_FLG_CONSTTIME); |
806 | 0 | if (!BN_MONT_CTX_set_locked(&pinfo->m, rsa->lock, factor, ctx)) { |
807 | 0 | BN_free(factor); |
808 | 0 | goto err; |
809 | 0 | } |
810 | 0 | } |
811 | 0 | #endif |
812 | | /* |
813 | | * We MUST free |factor| before any further use of the prime factors |
814 | | */ |
815 | 0 | BN_free(factor); |
816 | |
|
817 | 0 | smooth = (rsa->meth->bn_mod_exp == BN_mod_exp_mont) |
818 | 0 | #ifndef FIPS_MODULE |
819 | 0 | && (ex_primes == 0) |
820 | 0 | #endif |
821 | 0 | && (BN_num_bits(rsa->q) == BN_num_bits(rsa->p)); |
822 | 0 | } |
823 | | |
824 | 0 | if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) |
825 | 0 | if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n, rsa->lock, |
826 | 0 | rsa->n, ctx)) |
827 | 0 | goto err; |
828 | | |
829 | 0 | if (smooth) { |
830 | | /* |
831 | | * Conversion from Montgomery domain, a.k.a. Montgomery reduction, |
832 | | * accepts values in [0-m*2^w) range. w is m's bit width rounded up |
833 | | * to limb width. So that at the very least if |I| is fully reduced, |
834 | | * i.e. less than p*q, we can count on from-to round to perform |
835 | | * below modulo operations on |I|. Unlike BN_mod it's constant time. |
836 | | */ |
837 | 0 | if (/* m1 = I moq q */ |
838 | 0 | !bn_from_mont_fixed_top(m1, I, rsa->_method_mod_q, ctx) |
839 | 0 | || !bn_to_mont_fixed_top(m1, m1, rsa->_method_mod_q, ctx) |
840 | | /* r1 = I mod p */ |
841 | 0 | || !bn_from_mont_fixed_top(r1, I, rsa->_method_mod_p, ctx) |
842 | 0 | || !bn_to_mont_fixed_top(r1, r1, rsa->_method_mod_p, ctx) |
843 | | /* |
844 | | * Use parallel exponentiations optimization if possible, |
845 | | * otherwise fallback to two sequential exponentiations: |
846 | | * m1 = m1^dmq1 mod q |
847 | | * r1 = r1^dmp1 mod p |
848 | | */ |
849 | 0 | || !BN_mod_exp_mont_consttime_x2(m1, m1, rsa->dmq1, rsa->q, |
850 | 0 | rsa->_method_mod_q, |
851 | 0 | r1, r1, rsa->dmp1, rsa->p, |
852 | 0 | rsa->_method_mod_p, |
853 | 0 | ctx) |
854 | | /* r1 = (r1 - m1) mod p */ |
855 | | /* |
856 | | * bn_mod_sub_fixed_top is not regular modular subtraction, |
857 | | * it can tolerate subtrahend to be larger than modulus, but |
858 | | * not bit-wise wider. This makes up for uncommon q>p case, |
859 | | * when |m1| can be larger than |rsa->p|. |
860 | | */ |
861 | 0 | || !bn_mod_sub_fixed_top(r1, r1, m1, rsa->p) |
862 | | |
863 | | /* r1 = r1 * iqmp mod p */ |
864 | 0 | || !bn_to_mont_fixed_top(r1, r1, rsa->_method_mod_p, ctx) |
865 | 0 | || !bn_mul_mont_fixed_top(r1, r1, rsa->iqmp, rsa->_method_mod_p, |
866 | 0 | ctx) |
867 | | /* r0 = r1 * q + m1 */ |
868 | 0 | || !bn_mul_fixed_top(r0, r1, rsa->q, ctx) |
869 | 0 | || !bn_mod_add_fixed_top(r0, r0, m1, rsa->n)) |
870 | 0 | goto err; |
871 | | |
872 | 0 | goto tail; |
873 | 0 | } |
874 | | |
875 | | /* compute I mod q */ |
876 | 0 | { |
877 | 0 | BIGNUM *c = BN_new(); |
878 | 0 | if (c == NULL) |
879 | 0 | goto err; |
880 | 0 | BN_with_flags(c, I, BN_FLG_CONSTTIME); |
881 | |
|
882 | 0 | if (!BN_mod(r1, c, rsa->q, ctx)) { |
883 | 0 | BN_free(c); |
884 | 0 | goto err; |
885 | 0 | } |
886 | | |
887 | 0 | { |
888 | 0 | BIGNUM *dmq1 = BN_new(); |
889 | 0 | if (dmq1 == NULL) { |
890 | 0 | BN_free(c); |
891 | 0 | goto err; |
892 | 0 | } |
893 | 0 | BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME); |
894 | | |
895 | | /* compute r1^dmq1 mod q */ |
896 | 0 | if (!rsa->meth->bn_mod_exp(m1, r1, dmq1, rsa->q, ctx, |
897 | 0 | rsa->_method_mod_q)) { |
898 | 0 | BN_free(c); |
899 | 0 | BN_free(dmq1); |
900 | 0 | goto err; |
901 | 0 | } |
902 | | /* We MUST free dmq1 before any further use of rsa->dmq1 */ |
903 | 0 | BN_free(dmq1); |
904 | 0 | } |
905 | | |
906 | | /* compute I mod p */ |
907 | 0 | if (!BN_mod(r1, c, rsa->p, ctx)) { |
908 | 0 | BN_free(c); |
909 | 0 | goto err; |
910 | 0 | } |
911 | | /* We MUST free c before any further use of I */ |
912 | 0 | BN_free(c); |
913 | 0 | } |
914 | | |
915 | 0 | { |
916 | 0 | BIGNUM *dmp1 = BN_new(); |
917 | 0 | if (dmp1 == NULL) |
918 | 0 | goto err; |
919 | 0 | BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME); |
920 | | |
921 | | /* compute r1^dmp1 mod p */ |
922 | 0 | if (!rsa->meth->bn_mod_exp(r0, r1, dmp1, rsa->p, ctx, |
923 | 0 | rsa->_method_mod_p)) { |
924 | 0 | BN_free(dmp1); |
925 | 0 | goto err; |
926 | 0 | } |
927 | | /* We MUST free dmp1 before any further use of rsa->dmp1 */ |
928 | 0 | BN_free(dmp1); |
929 | 0 | } |
930 | | |
931 | 0 | #ifndef FIPS_MODULE |
932 | 0 | if (ex_primes > 0) { |
933 | 0 | BIGNUM *di = BN_new(), *cc = BN_new(); |
934 | |
|
935 | 0 | if (cc == NULL || di == NULL) { |
936 | 0 | BN_free(cc); |
937 | 0 | BN_free(di); |
938 | 0 | goto err; |
939 | 0 | } |
940 | | |
941 | 0 | for (i = 0; i < ex_primes; i++) { |
942 | | /* prepare m_i */ |
943 | 0 | if ((m[i] = BN_CTX_get(ctx)) == NULL) { |
944 | 0 | BN_free(cc); |
945 | 0 | BN_free(di); |
946 | 0 | goto err; |
947 | 0 | } |
948 | | |
949 | 0 | pinfo = sk_RSA_PRIME_INFO_value(rsa->prime_infos, i); |
950 | | |
951 | | /* prepare c and d_i */ |
952 | 0 | BN_with_flags(cc, I, BN_FLG_CONSTTIME); |
953 | 0 | BN_with_flags(di, pinfo->d, BN_FLG_CONSTTIME); |
954 | |
|
955 | 0 | if (!BN_mod(r1, cc, pinfo->r, ctx)) { |
956 | 0 | BN_free(cc); |
957 | 0 | BN_free(di); |
958 | 0 | goto err; |
959 | 0 | } |
960 | | /* compute r1 ^ d_i mod r_i */ |
961 | 0 | if (!rsa->meth->bn_mod_exp(m[i], r1, di, pinfo->r, ctx, pinfo->m)) { |
962 | 0 | BN_free(cc); |
963 | 0 | BN_free(di); |
964 | 0 | goto err; |
965 | 0 | } |
966 | 0 | } |
967 | | |
968 | 0 | BN_free(cc); |
969 | 0 | BN_free(di); |
970 | 0 | } |
971 | 0 | #endif |
972 | | |
973 | 0 | if (!BN_sub(r0, r0, m1)) |
974 | 0 | goto err; |
975 | | /* |
976 | | * This will help stop the size of r0 increasing, which does affect the |
977 | | * multiply if it optimised for a power of 2 size |
978 | | */ |
979 | 0 | if (BN_is_negative(r0)) |
980 | 0 | if (!BN_add(r0, r0, rsa->p)) |
981 | 0 | goto err; |
982 | | |
983 | 0 | if (!BN_mul(r1, r0, rsa->iqmp, ctx)) |
984 | 0 | goto err; |
985 | | |
986 | 0 | { |
987 | 0 | BIGNUM *pr1 = BN_new(); |
988 | 0 | if (pr1 == NULL) |
989 | 0 | goto err; |
990 | 0 | BN_with_flags(pr1, r1, BN_FLG_CONSTTIME); |
991 | |
|
992 | 0 | if (!BN_mod(r0, pr1, rsa->p, ctx)) { |
993 | 0 | BN_free(pr1); |
994 | 0 | goto err; |
995 | 0 | } |
996 | | /* We MUST free pr1 before any further use of r1 */ |
997 | 0 | BN_free(pr1); |
998 | 0 | } |
999 | | |
1000 | | /* |
1001 | | * If p < q it is occasionally possible for the correction of adding 'p' |
1002 | | * if r0 is negative above to leave the result still negative. This can |
1003 | | * break the private key operations: the following second correction |
1004 | | * should *always* correct this rare occurrence. This will *never* happen |
1005 | | * with OpenSSL generated keys because they ensure p > q [steve] |
1006 | | */ |
1007 | 0 | if (BN_is_negative(r0)) |
1008 | 0 | if (!BN_add(r0, r0, rsa->p)) |
1009 | 0 | goto err; |
1010 | 0 | if (!BN_mul(r1, r0, rsa->q, ctx)) |
1011 | 0 | goto err; |
1012 | 0 | if (!BN_add(r0, r1, m1)) |
1013 | 0 | goto err; |
1014 | | |
1015 | 0 | #ifndef FIPS_MODULE |
1016 | | /* add m_i to m in multi-prime case */ |
1017 | 0 | if (ex_primes > 0) { |
1018 | 0 | BIGNUM *pr2 = BN_new(); |
1019 | |
|
1020 | 0 | if (pr2 == NULL) |
1021 | 0 | goto err; |
1022 | | |
1023 | 0 | for (i = 0; i < ex_primes; i++) { |
1024 | 0 | pinfo = sk_RSA_PRIME_INFO_value(rsa->prime_infos, i); |
1025 | 0 | if (!BN_sub(r1, m[i], r0)) { |
1026 | 0 | BN_free(pr2); |
1027 | 0 | goto err; |
1028 | 0 | } |
1029 | | |
1030 | 0 | if (!BN_mul(r2, r1, pinfo->t, ctx)) { |
1031 | 0 | BN_free(pr2); |
1032 | 0 | goto err; |
1033 | 0 | } |
1034 | | |
1035 | 0 | BN_with_flags(pr2, r2, BN_FLG_CONSTTIME); |
1036 | |
|
1037 | 0 | if (!BN_mod(r1, pr2, pinfo->r, ctx)) { |
1038 | 0 | BN_free(pr2); |
1039 | 0 | goto err; |
1040 | 0 | } |
1041 | | |
1042 | 0 | if (BN_is_negative(r1)) |
1043 | 0 | if (!BN_add(r1, r1, pinfo->r)) { |
1044 | 0 | BN_free(pr2); |
1045 | 0 | goto err; |
1046 | 0 | } |
1047 | 0 | if (!BN_mul(r1, r1, pinfo->pp, ctx)) { |
1048 | 0 | BN_free(pr2); |
1049 | 0 | goto err; |
1050 | 0 | } |
1051 | 0 | if (!BN_add(r0, r0, r1)) { |
1052 | 0 | BN_free(pr2); |
1053 | 0 | goto err; |
1054 | 0 | } |
1055 | 0 | } |
1056 | 0 | BN_free(pr2); |
1057 | 0 | } |
1058 | 0 | #endif |
1059 | | |
1060 | 0 | tail: |
1061 | 0 | if (rsa->e && rsa->n) { |
1062 | 0 | if (rsa->meth->bn_mod_exp == BN_mod_exp_mont) { |
1063 | 0 | if (!BN_mod_exp_mont(vrfy, r0, rsa->e, rsa->n, ctx, |
1064 | 0 | rsa->_method_mod_n)) |
1065 | 0 | goto err; |
1066 | 0 | } else { |
1067 | 0 | bn_correct_top(r0); |
1068 | 0 | if (!rsa->meth->bn_mod_exp(vrfy, r0, rsa->e, rsa->n, ctx, |
1069 | 0 | rsa->_method_mod_n)) |
1070 | 0 | goto err; |
1071 | 0 | } |
1072 | | /* |
1073 | | * If 'I' was greater than (or equal to) rsa->n, the operation will |
1074 | | * be equivalent to using 'I mod n'. However, the result of the |
1075 | | * verify will *always* be less than 'n' so we don't check for |
1076 | | * absolute equality, just congruency. |
1077 | | */ |
1078 | 0 | if (!BN_sub(vrfy, vrfy, I)) |
1079 | 0 | goto err; |
1080 | 0 | if (BN_is_zero(vrfy)) { |
1081 | 0 | bn_correct_top(r0); |
1082 | 0 | ret = 1; |
1083 | 0 | goto err; /* not actually error */ |
1084 | 0 | } |
1085 | 0 | if (!BN_mod(vrfy, vrfy, rsa->n, ctx)) |
1086 | 0 | goto err; |
1087 | 0 | if (BN_is_negative(vrfy)) |
1088 | 0 | if (!BN_add(vrfy, vrfy, rsa->n)) |
1089 | 0 | goto err; |
1090 | 0 | if (!BN_is_zero(vrfy)) { |
1091 | | /* |
1092 | | * 'I' and 'vrfy' aren't congruent mod n. Don't leak |
1093 | | * miscalculated CRT output, just do a raw (slower) mod_exp and |
1094 | | * return that instead. |
1095 | | */ |
1096 | |
|
1097 | 0 | BIGNUM *d = BN_new(); |
1098 | 0 | if (d == NULL) |
1099 | 0 | goto err; |
1100 | 0 | BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME); |
1101 | |
|
1102 | 0 | if (!rsa->meth->bn_mod_exp(r0, I, d, rsa->n, ctx, |
1103 | 0 | rsa->_method_mod_n)) { |
1104 | 0 | BN_free(d); |
1105 | 0 | goto err; |
1106 | 0 | } |
1107 | | /* We MUST free d before any further use of rsa->d */ |
1108 | 0 | BN_free(d); |
1109 | 0 | } |
1110 | 0 | } |
1111 | | /* |
1112 | | * It's unfortunate that we have to bn_correct_top(r0). What hopefully |
1113 | | * saves the day is that correction is highly unlike, and private key |
1114 | | * operations are customarily performed on blinded message. Which means |
1115 | | * that attacker won't observe correlation with chosen plaintext. |
1116 | | * Secondly, remaining code would still handle it in same computational |
1117 | | * time and even conceal memory access pattern around corrected top. |
1118 | | */ |
1119 | 0 | bn_correct_top(r0); |
1120 | 0 | ret = 1; |
1121 | 0 | err: |
1122 | 0 | BN_CTX_end(ctx); |
1123 | 0 | return ret; |
1124 | 0 | } |
1125 | | |
1126 | | static int rsa_ossl_init(RSA *rsa) |
1127 | 9.53k | { |
1128 | 9.53k | rsa->flags |= RSA_FLAG_CACHE_PUBLIC | RSA_FLAG_CACHE_PRIVATE; |
1129 | 9.53k | return 1; |
1130 | 9.53k | } |
1131 | | |
1132 | | static int rsa_ossl_finish(RSA *rsa) |
1133 | 9.53k | { |
1134 | 9.53k | #ifndef FIPS_MODULE |
1135 | 9.53k | int i; |
1136 | 9.53k | RSA_PRIME_INFO *pinfo; |
1137 | | |
1138 | 9.53k | for (i = 0; i < sk_RSA_PRIME_INFO_num(rsa->prime_infos); i++) { |
1139 | 0 | pinfo = sk_RSA_PRIME_INFO_value(rsa->prime_infos, i); |
1140 | 0 | BN_MONT_CTX_free(pinfo->m); |
1141 | 0 | } |
1142 | 9.53k | #endif |
1143 | | |
1144 | 9.53k | BN_MONT_CTX_free(rsa->_method_mod_n); |
1145 | 9.53k | BN_MONT_CTX_free(rsa->_method_mod_p); |
1146 | 9.53k | BN_MONT_CTX_free(rsa->_method_mod_q); |
1147 | 9.53k | return 1; |
1148 | 9.53k | } |
1149 | | |
1150 | | #ifdef S390X_MOD_EXP |
1151 | | static int rsa_ossl_s390x_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa, |
1152 | | BN_CTX *ctx) |
1153 | | { |
1154 | | if (rsa->version != RSA_ASN1_VERSION_MULTI) { |
1155 | | if (s390x_crt(r0, i, rsa->p, rsa->q, rsa->dmp1, rsa->dmq1, rsa->iqmp) == 1) |
1156 | | return 1; |
1157 | | } |
1158 | | return rsa_ossl_mod_exp(r0, i, rsa, ctx); |
1159 | | } |
1160 | | |
1161 | | #endif |