]>
Commit | Line | Data |
---|---|---|
4f22f405 | 1 | /* |
3c2bdd7d | 2 | * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved. |
f8989a21 | 3 | * |
367ace68 | 4 | * Licensed under the Apache License 2.0 (the "License"). You may not use |
4f22f405 RS |
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 | |
f8989a21 BM |
8 | */ |
9 | ||
b39fc560 | 10 | #include "internal/cryptlib.h" |
706457b7 DMSP |
11 | #include "internal/constant_time.h" |
12 | #include "bn_local.h" | |
6dad7bd6 | 13 | |
361512da AP |
14 | #include <stdlib.h> |
15 | #ifdef _WIN32 | |
16 | # include <malloc.h> | |
17 | # ifndef alloca | |
18 | # define alloca _alloca | |
19 | # endif | |
20 | #elif defined(__GNUC__) | |
21 | # ifndef alloca | |
22 | # define alloca(s) __builtin_alloca((s)) | |
23 | # endif | |
b74ce8d9 AP |
24 | #elif defined(__sun) |
25 | # include <alloca.h> | |
361512da AP |
26 | #endif |
27 | ||
ed45f3c2 | 28 | #include "rsaz_exp.h" |
ca48ace5 | 29 | |
cbce8c46 | 30 | #undef SPARC_T4_MONT |
b69437e1 | 31 | #if defined(OPENSSL_BN_ASM_MONT) && (defined(__sparc__) || defined(__sparc)) |
68c06bf6 AP |
32 | # include "sparc_arch.h" |
33 | extern unsigned int OPENSSL_sparcv9cap_P[]; | |
cbce8c46 | 34 | # define SPARC_T4_MONT |
68c06bf6 AP |
35 | #endif |
36 | ||
46a64376 | 37 | /* maximum precomputation table size for *variable* sliding windows */ |
0f113f3e | 38 | #define TABLE_SIZE 32 |
dfeab068 | 39 | |
58964a49 | 40 | /* this one works - simple but works */ |
020fc820 | 41 | int BN_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx) |
0f113f3e MC |
42 | { |
43 | int i, bits, ret = 0; | |
44 | BIGNUM *v, *rr; | |
45 | ||
e913d11f MC |
46 | if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0 |
47 | || BN_get_flags(a, BN_FLG_CONSTTIME) != 0) { | |
0f113f3e | 48 | /* BN_FLG_CONSTTIME only supported by BN_mod_exp_mont() */ |
9311d0c4 | 49 | ERR_raise(ERR_LIB_BN, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); |
0818dbad | 50 | return 0; |
0f113f3e MC |
51 | } |
52 | ||
53 | BN_CTX_start(ctx); | |
edea42c6 | 54 | rr = ((r == a) || (r == p)) ? BN_CTX_get(ctx) : r; |
0f113f3e MC |
55 | v = BN_CTX_get(ctx); |
56 | if (rr == NULL || v == NULL) | |
57 | goto err; | |
58 | ||
59 | if (BN_copy(v, a) == NULL) | |
60 | goto err; | |
61 | bits = BN_num_bits(p); | |
62 | ||
63 | if (BN_is_odd(p)) { | |
64 | if (BN_copy(rr, a) == NULL) | |
65 | goto err; | |
66 | } else { | |
67 | if (!BN_one(rr)) | |
68 | goto err; | |
69 | } | |
70 | ||
71 | for (i = 1; i < bits; i++) { | |
72 | if (!BN_sqr(v, v, ctx)) | |
73 | goto err; | |
74 | if (BN_is_bit_set(p, i)) { | |
75 | if (!BN_mul(rr, rr, v, ctx)) | |
76 | goto err; | |
77 | } | |
78 | } | |
78e09b53 RS |
79 | if (r != rr && BN_copy(r, rr) == NULL) |
80 | goto err; | |
81 | ||
8c5a7b33 MC |
82 | ret = 1; |
83 | err: | |
0f113f3e MC |
84 | BN_CTX_end(ctx); |
85 | bn_check_top(r); | |
edea42c6 | 86 | return ret; |
0f113f3e | 87 | } |
6dad7bd6 | 88 | |
020fc820 | 89 | int BN_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, const BIGNUM *m, |
0f113f3e MC |
90 | BN_CTX *ctx) |
91 | { | |
92 | int ret; | |
93 | ||
94 | bn_check_top(a); | |
95 | bn_check_top(p); | |
96 | bn_check_top(m); | |
97 | ||
50e735f9 | 98 | /*- |
02e112a8 | 99 | * For even modulus m = 2^k*m_odd, it might make sense to compute |
50e735f9 MC |
100 | * a^p mod m_odd and a^p mod 2^k separately (with Montgomery |
101 | * exponentiation for the odd part), using appropriate exponent | |
102 | * reductions, and combine the results using the CRT. | |
103 | * | |
104 | * For now, we use Montgomery only if the modulus is odd; otherwise, | |
105 | * exponentiation using the reciprocal-based quick remaindering | |
106 | * algorithm is used. | |
107 | * | |
108 | * (Timing obtained with expspeed.c [computations a^p mod m | |
109 | * where a, p, m are of the same length: 256, 512, 1024, 2048, | |
110 | * 4096, 8192 bits], compared to the running time of the | |
111 | * standard algorithm: | |
112 | * | |
113 | * BN_mod_exp_mont 33 .. 40 % [AMD K6-2, Linux, debug configuration] | |
114 | * 55 .. 77 % [UltraSparc processor, but | |
115 | * debug-solaris-sparcv8-gcc conf.] | |
116 | * | |
117 | * BN_mod_exp_recp 50 .. 70 % [AMD K6-2, Linux, debug configuration] | |
118 | * 62 .. 118 % [UltraSparc, debug-solaris-sparcv8-gcc] | |
119 | * | |
120 | * On the Sparc, BN_mod_exp_recp was faster than BN_mod_exp_mont | |
121 | * at 2048 and more bits, but at 512 and 1024 bits, it was | |
122 | * slower even than the standard algorithm! | |
123 | * | |
124 | * "Real" timings [linux-elf, solaris-sparcv9-gcc configurations] | |
125 | * should be obtained when the new Montgomery reduction code | |
126 | * has been integrated into OpenSSL.) | |
127 | */ | |
78a0c1f1 BM |
128 | |
129 | #define MONT_MUL_MOD | |
25439b76 | 130 | #define MONT_EXP_WORD |
78a0c1f1 BM |
131 | #define RECP_MUL_MOD |
132 | ||
d02b48c6 | 133 | #ifdef MONT_MUL_MOD |
0f113f3e MC |
134 | if (BN_is_odd(m)) { |
135 | # ifdef MONT_EXP_WORD | |
136 | if (a->top == 1 && !a->neg | |
e913d11f MC |
137 | && (BN_get_flags(p, BN_FLG_CONSTTIME) == 0) |
138 | && (BN_get_flags(a, BN_FLG_CONSTTIME) == 0) | |
139 | && (BN_get_flags(m, BN_FLG_CONSTTIME) == 0)) { | |
0f113f3e MC |
140 | BN_ULONG A = a->d[0]; |
141 | ret = BN_mod_exp_mont_word(r, A, p, m, ctx, NULL); | |
142 | } else | |
143 | # endif | |
144 | ret = BN_mod_exp_mont(r, a, p, m, ctx, NULL); | |
145 | } else | |
d02b48c6 RE |
146 | #endif |
147 | #ifdef RECP_MUL_MOD | |
0f113f3e MC |
148 | { |
149 | ret = BN_mod_exp_recp(r, a, p, m, ctx); | |
150 | } | |
d02b48c6 | 151 | #else |
0f113f3e MC |
152 | { |
153 | ret = BN_mod_exp_simple(r, a, p, m, ctx); | |
154 | } | |
d02b48c6 RE |
155 | #endif |
156 | ||
0f113f3e | 157 | bn_check_top(r); |
26a7d938 | 158 | return ret; |
0f113f3e | 159 | } |
6dad7bd6 | 160 | |
84c15db5 | 161 | int BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, |
0f113f3e MC |
162 | const BIGNUM *m, BN_CTX *ctx) |
163 | { | |
164 | int i, j, bits, ret = 0, wstart, wend, window, wvalue; | |
165 | int start = 1; | |
166 | BIGNUM *aa; | |
167 | /* Table of variables obtained from 'ctx' */ | |
168 | BIGNUM *val[TABLE_SIZE]; | |
169 | BN_RECP_CTX recp; | |
170 | ||
e913d11f MC |
171 | if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0 |
172 | || BN_get_flags(a, BN_FLG_CONSTTIME) != 0 | |
173 | || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) { | |
0f113f3e | 174 | /* BN_FLG_CONSTTIME only supported by BN_mod_exp_mont() */ |
9311d0c4 | 175 | ERR_raise(ERR_LIB_BN, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); |
0818dbad | 176 | return 0; |
0f113f3e MC |
177 | } |
178 | ||
179 | bits = BN_num_bits(p); | |
0f113f3e | 180 | if (bits == 0) { |
4aa5b725 MC |
181 | /* x**0 mod 1, or x**0 mod -1 is still zero. */ |
182 | if (BN_abs_is_word(m, 1)) { | |
d911097d EK |
183 | ret = 1; |
184 | BN_zero(r); | |
185 | } else { | |
186 | ret = BN_one(r); | |
187 | } | |
0f113f3e MC |
188 | return ret; |
189 | } | |
190 | ||
191 | BN_CTX_start(ctx); | |
192 | aa = BN_CTX_get(ctx); | |
193 | val[0] = BN_CTX_get(ctx); | |
edea42c6 | 194 | if (val[0] == NULL) |
0f113f3e MC |
195 | goto err; |
196 | ||
197 | BN_RECP_CTX_init(&recp); | |
198 | if (m->neg) { | |
199 | /* ignore sign of 'm' */ | |
200 | if (!BN_copy(aa, m)) | |
201 | goto err; | |
202 | aa->neg = 0; | |
203 | if (BN_RECP_CTX_set(&recp, aa, ctx) <= 0) | |
204 | goto err; | |
205 | } else { | |
206 | if (BN_RECP_CTX_set(&recp, m, ctx) <= 0) | |
207 | goto err; | |
208 | } | |
209 | ||
210 | if (!BN_nnmod(val[0], a, m, ctx)) | |
211 | goto err; /* 1 */ | |
212 | if (BN_is_zero(val[0])) { | |
213 | BN_zero(r); | |
214 | ret = 1; | |
215 | goto err; | |
216 | } | |
217 | ||
218 | window = BN_window_bits_for_exponent_size(bits); | |
219 | if (window > 1) { | |
220 | if (!BN_mod_mul_reciprocal(aa, val[0], val[0], &recp, ctx)) | |
221 | goto err; /* 2 */ | |
222 | j = 1 << (window - 1); | |
223 | for (i = 1; i < j; i++) { | |
224 | if (((val[i] = BN_CTX_get(ctx)) == NULL) || | |
225 | !BN_mod_mul_reciprocal(val[i], val[i - 1], aa, &recp, ctx)) | |
226 | goto err; | |
227 | } | |
228 | } | |
229 | ||
230 | start = 1; /* This is used to avoid multiplication etc | |
231 | * when there is only the value '1' in the | |
232 | * buffer. */ | |
233 | wvalue = 0; /* The 'value' of the window */ | |
234 | wstart = bits - 1; /* The top bit of the window */ | |
235 | wend = 0; /* The bottom bit of the window */ | |
236 | ||
237 | if (!BN_one(r)) | |
238 | goto err; | |
239 | ||
240 | for (;;) { | |
241 | if (BN_is_bit_set(p, wstart) == 0) { | |
242 | if (!start) | |
243 | if (!BN_mod_mul_reciprocal(r, r, r, &recp, ctx)) | |
244 | goto err; | |
245 | if (wstart == 0) | |
246 | break; | |
247 | wstart--; | |
248 | continue; | |
249 | } | |
250 | /* | |
251 | * We now have wstart on a 'set' bit, we now need to work out how bit | |
252 | * a window to do. To do this we need to scan forward until the last | |
253 | * set bit before the end of the window | |
254 | */ | |
0f113f3e MC |
255 | wvalue = 1; |
256 | wend = 0; | |
257 | for (i = 1; i < window; i++) { | |
258 | if (wstart - i < 0) | |
259 | break; | |
260 | if (BN_is_bit_set(p, wstart - i)) { | |
261 | wvalue <<= (i - wend); | |
262 | wvalue |= 1; | |
263 | wend = i; | |
264 | } | |
265 | } | |
266 | ||
267 | /* wend is the size of the current window */ | |
268 | j = wend + 1; | |
269 | /* add the 'bytes above' */ | |
270 | if (!start) | |
271 | for (i = 0; i < j; i++) { | |
272 | if (!BN_mod_mul_reciprocal(r, r, r, &recp, ctx)) | |
273 | goto err; | |
274 | } | |
275 | ||
276 | /* wvalue will be an odd number < 2^window */ | |
277 | if (!BN_mod_mul_reciprocal(r, r, val[wvalue >> 1], &recp, ctx)) | |
278 | goto err; | |
279 | ||
280 | /* move the 'window' down further */ | |
281 | wstart -= wend + 1; | |
282 | wvalue = 0; | |
283 | start = 0; | |
284 | if (wstart < 0) | |
285 | break; | |
286 | } | |
287 | ret = 1; | |
288 | err: | |
289 | BN_CTX_end(ctx); | |
290 | BN_RECP_CTX_free(&recp); | |
291 | bn_check_top(r); | |
26a7d938 | 292 | return ret; |
0f113f3e | 293 | } |
6dad7bd6 | 294 | |
020fc820 | 295 | int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p, |
0f113f3e MC |
296 | const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont) |
297 | { | |
298 | int i, j, bits, ret = 0, wstart, wend, window, wvalue; | |
299 | int start = 1; | |
300 | BIGNUM *d, *r; | |
301 | const BIGNUM *aa; | |
302 | /* Table of variables obtained from 'ctx' */ | |
303 | BIGNUM *val[TABLE_SIZE]; | |
304 | BN_MONT_CTX *mont = NULL; | |
305 | ||
e913d11f MC |
306 | if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0 |
307 | || BN_get_flags(a, BN_FLG_CONSTTIME) != 0 | |
308 | || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) { | |
0f113f3e MC |
309 | return BN_mod_exp_mont_consttime(rr, a, p, m, ctx, in_mont); |
310 | } | |
311 | ||
312 | bn_check_top(a); | |
313 | bn_check_top(p); | |
314 | bn_check_top(m); | |
315 | ||
316 | if (!BN_is_odd(m)) { | |
9311d0c4 | 317 | ERR_raise(ERR_LIB_BN, BN_R_CALLED_WITH_EVEN_MODULUS); |
26a7d938 | 318 | return 0; |
0f113f3e MC |
319 | } |
320 | bits = BN_num_bits(p); | |
321 | if (bits == 0) { | |
4aa5b725 MC |
322 | /* x**0 mod 1, or x**0 mod -1 is still zero. */ |
323 | if (BN_abs_is_word(m, 1)) { | |
d911097d EK |
324 | ret = 1; |
325 | BN_zero(rr); | |
326 | } else { | |
327 | ret = BN_one(rr); | |
328 | } | |
0f113f3e MC |
329 | return ret; |
330 | } | |
331 | ||
332 | BN_CTX_start(ctx); | |
333 | d = BN_CTX_get(ctx); | |
334 | r = BN_CTX_get(ctx); | |
335 | val[0] = BN_CTX_get(ctx); | |
edea42c6 | 336 | if (val[0] == NULL) |
0f113f3e MC |
337 | goto err; |
338 | ||
339 | /* | |
340 | * If this is not done, things will break in the montgomery part | |
341 | */ | |
342 | ||
343 | if (in_mont != NULL) | |
344 | mont = in_mont; | |
345 | else { | |
346 | if ((mont = BN_MONT_CTX_new()) == NULL) | |
347 | goto err; | |
348 | if (!BN_MONT_CTX_set(mont, m, ctx)) | |
349 | goto err; | |
350 | } | |
351 | ||
352 | if (a->neg || BN_ucmp(a, m) >= 0) { | |
353 | if (!BN_nnmod(val[0], a, m, ctx)) | |
354 | goto err; | |
355 | aa = val[0]; | |
356 | } else | |
357 | aa = a; | |
71883868 | 358 | if (!bn_to_mont_fixed_top(val[0], aa, mont, ctx)) |
0f113f3e MC |
359 | goto err; /* 1 */ |
360 | ||
361 | window = BN_window_bits_for_exponent_size(bits); | |
362 | if (window > 1) { | |
71883868 | 363 | if (!bn_mul_mont_fixed_top(d, val[0], val[0], mont, ctx)) |
0f113f3e MC |
364 | goto err; /* 2 */ |
365 | j = 1 << (window - 1); | |
366 | for (i = 1; i < j; i++) { | |
367 | if (((val[i] = BN_CTX_get(ctx)) == NULL) || | |
71883868 | 368 | !bn_mul_mont_fixed_top(val[i], val[i - 1], d, mont, ctx)) |
0f113f3e MC |
369 | goto err; |
370 | } | |
371 | } | |
372 | ||
373 | start = 1; /* This is used to avoid multiplication etc | |
374 | * when there is only the value '1' in the | |
375 | * buffer. */ | |
376 | wvalue = 0; /* The 'value' of the window */ | |
377 | wstart = bits - 1; /* The top bit of the window */ | |
378 | wend = 0; /* The bottom bit of the window */ | |
379 | ||
380 | #if 1 /* by Shay Gueron's suggestion */ | |
381 | j = m->top; /* borrow j */ | |
382 | if (m->d[j - 1] & (((BN_ULONG)1) << (BN_BITS2 - 1))) { | |
383 | if (bn_wexpand(r, j) == NULL) | |
384 | goto err; | |
385 | /* 2^(top*BN_BITS2) - m */ | |
386 | r->d[0] = (0 - m->d[0]) & BN_MASK2; | |
387 | for (i = 1; i < j; i++) | |
388 | r->d[i] = (~m->d[i]) & BN_MASK2; | |
389 | r->top = j; | |
71883868 | 390 | r->flags |= BN_FLG_FIXED_TOP; |
0f113f3e | 391 | } else |
4ddacd99 | 392 | #endif |
71883868 | 393 | if (!bn_to_mont_fixed_top(r, BN_value_one(), mont, ctx)) |
0f113f3e MC |
394 | goto err; |
395 | for (;;) { | |
396 | if (BN_is_bit_set(p, wstart) == 0) { | |
397 | if (!start) { | |
71883868 | 398 | if (!bn_mul_mont_fixed_top(r, r, r, mont, ctx)) |
0f113f3e MC |
399 | goto err; |
400 | } | |
401 | if (wstart == 0) | |
402 | break; | |
403 | wstart--; | |
404 | continue; | |
405 | } | |
406 | /* | |
407 | * We now have wstart on a 'set' bit, we now need to work out how bit | |
408 | * a window to do. To do this we need to scan forward until the last | |
409 | * set bit before the end of the window | |
410 | */ | |
0f113f3e MC |
411 | wvalue = 1; |
412 | wend = 0; | |
413 | for (i = 1; i < window; i++) { | |
414 | if (wstart - i < 0) | |
415 | break; | |
416 | if (BN_is_bit_set(p, wstart - i)) { | |
417 | wvalue <<= (i - wend); | |
418 | wvalue |= 1; | |
419 | wend = i; | |
420 | } | |
421 | } | |
422 | ||
423 | /* wend is the size of the current window */ | |
424 | j = wend + 1; | |
425 | /* add the 'bytes above' */ | |
426 | if (!start) | |
427 | for (i = 0; i < j; i++) { | |
71883868 | 428 | if (!bn_mul_mont_fixed_top(r, r, r, mont, ctx)) |
0f113f3e MC |
429 | goto err; |
430 | } | |
431 | ||
432 | /* wvalue will be an odd number < 2^window */ | |
71883868 | 433 | if (!bn_mul_mont_fixed_top(r, r, val[wvalue >> 1], mont, ctx)) |
0f113f3e MC |
434 | goto err; |
435 | ||
436 | /* move the 'window' down further */ | |
437 | wstart -= wend + 1; | |
438 | wvalue = 0; | |
439 | start = 0; | |
440 | if (wstart < 0) | |
441 | break; | |
442 | } | |
71883868 AP |
443 | /* |
444 | * Done with zero-padded intermediate BIGNUMs. Final BN_from_montgomery | |
445 | * removes padding [if any] and makes return value suitable for public | |
446 | * API consumer. | |
447 | */ | |
cbce8c46 | 448 | #if defined(SPARC_T4_MONT) |
0f113f3e MC |
449 | if (OPENSSL_sparcv9cap_P[0] & (SPARCV9_VIS3 | SPARCV9_PREFER_FPU)) { |
450 | j = mont->N.top; /* borrow j */ | |
451 | val[0]->d[0] = 1; /* borrow val[0] */ | |
452 | for (i = 1; i < j; i++) | |
453 | val[0]->d[i] = 0; | |
454 | val[0]->top = j; | |
455 | if (!BN_mod_mul_montgomery(rr, r, val[0], mont, ctx)) | |
456 | goto err; | |
457 | } else | |
4ddacd99 | 458 | #endif |
0f113f3e MC |
459 | if (!BN_from_montgomery(rr, r, mont, ctx)) |
460 | goto err; | |
461 | ret = 1; | |
462 | err: | |
23a1d5e9 | 463 | if (in_mont == NULL) |
0f113f3e MC |
464 | BN_MONT_CTX_free(mont); |
465 | BN_CTX_end(ctx); | |
466 | bn_check_top(rr); | |
26a7d938 | 467 | return ret; |
0f113f3e | 468 | } |
6dad7bd6 | 469 | |
4ddacd99 | 470 | static BN_ULONG bn_get_bits(const BIGNUM *a, int bitpos) |
0f113f3e MC |
471 | { |
472 | BN_ULONG ret = 0; | |
473 | int wordpos; | |
474 | ||
475 | wordpos = bitpos / BN_BITS2; | |
476 | bitpos %= BN_BITS2; | |
477 | if (wordpos >= 0 && wordpos < a->top) { | |
478 | ret = a->d[wordpos] & BN_MASK2; | |
479 | if (bitpos) { | |
480 | ret >>= bitpos; | |
481 | if (++wordpos < a->top) | |
482 | ret |= a->d[wordpos] << (BN_BITS2 - bitpos); | |
483 | } | |
484 | } | |
485 | ||
486 | return ret & BN_MASK2; | |
4ddacd99 | 487 | } |
46a64376 | 488 | |
0f113f3e MC |
489 | /* |
490 | * BN_mod_exp_mont_consttime() stores the precomputed powers in a specific | |
491 | * layout so that accessing any of these table values shows the same access | |
492 | * pattern as far as cache lines are concerned. The following functions are | |
493 | * used to transfer a BIGNUM from/to that table. | |
494 | */ | |
46a64376 | 495 | |
0f113f3e MC |
496 | static int MOD_EXP_CTIME_COPY_TO_PREBUF(const BIGNUM *b, int top, |
497 | unsigned char *buf, int idx, | |
d6482a82 | 498 | int window) |
0f113f3e | 499 | { |
d6482a82 AP |
500 | int i, j; |
501 | int width = 1 << window; | |
502 | BN_ULONG *table = (BN_ULONG *)buf; | |
46a64376 | 503 | |
0f113f3e MC |
504 | if (top > b->top) |
505 | top = b->top; /* this works because 'buf' is explicitly | |
506 | * zeroed */ | |
d6482a82 AP |
507 | for (i = 0, j = idx; i < top; i++, j += width) { |
508 | table[j] = b->d[i]; | |
0f113f3e | 509 | } |
46a64376 | 510 | |
0f113f3e MC |
511 | return 1; |
512 | } | |
46a64376 | 513 | |
0f113f3e MC |
514 | static int MOD_EXP_CTIME_COPY_FROM_PREBUF(BIGNUM *b, int top, |
515 | unsigned char *buf, int idx, | |
d6482a82 | 516 | int window) |
0f113f3e | 517 | { |
d6482a82 AP |
518 | int i, j; |
519 | int width = 1 << window; | |
bb83c879 AP |
520 | /* |
521 | * We declare table 'volatile' in order to discourage compiler | |
522 | * from reordering loads from the table. Concern is that if | |
523 | * reordered in specific manner loads might give away the | |
524 | * information we are trying to conceal. Some would argue that | |
525 | * compiler can reorder them anyway, but it can as well be | |
526 | * argued that doing so would be violation of standard... | |
527 | */ | |
d6482a82 | 528 | volatile BN_ULONG *table = (volatile BN_ULONG *)buf; |
46a64376 | 529 | |
0f113f3e MC |
530 | if (bn_wexpand(b, top) == NULL) |
531 | return 0; | |
46a64376 | 532 | |
d6482a82 AP |
533 | if (window <= 3) { |
534 | for (i = 0; i < top; i++, table += width) { | |
535 | BN_ULONG acc = 0; | |
536 | ||
537 | for (j = 0; j < width; j++) { | |
538 | acc |= table[j] & | |
539 | ((BN_ULONG)0 - (constant_time_eq_int(j,idx)&1)); | |
540 | } | |
541 | ||
542 | b->d[i] = acc; | |
543 | } | |
544 | } else { | |
545 | int xstride = 1 << (window - 2); | |
546 | BN_ULONG y0, y1, y2, y3; | |
547 | ||
548 | i = idx >> (window - 2); /* equivalent of idx / xstride */ | |
549 | idx &= xstride - 1; /* equivalent of idx % xstride */ | |
550 | ||
551 | y0 = (BN_ULONG)0 - (constant_time_eq_int(i,0)&1); | |
552 | y1 = (BN_ULONG)0 - (constant_time_eq_int(i,1)&1); | |
553 | y2 = (BN_ULONG)0 - (constant_time_eq_int(i,2)&1); | |
554 | y3 = (BN_ULONG)0 - (constant_time_eq_int(i,3)&1); | |
555 | ||
556 | for (i = 0; i < top; i++, table += width) { | |
557 | BN_ULONG acc = 0; | |
558 | ||
559 | for (j = 0; j < xstride; j++) { | |
560 | acc |= ( (table[j + 0 * xstride] & y0) | | |
561 | (table[j + 1 * xstride] & y1) | | |
562 | (table[j + 2 * xstride] & y2) | | |
563 | (table[j + 3 * xstride] & y3) ) | |
564 | & ((BN_ULONG)0 - (constant_time_eq_int(j,idx)&1)); | |
565 | } | |
566 | ||
567 | b->d[i] = acc; | |
568 | } | |
0f113f3e | 569 | } |
46a64376 | 570 | |
0f113f3e | 571 | b->top = top; |
71883868 | 572 | b->flags |= BN_FLG_FIXED_TOP; |
0f113f3e MC |
573 | return 1; |
574 | } | |
46a64376 | 575 | |
0f113f3e MC |
576 | /* |
577 | * Given a pointer value, compute the next address that is a cache line | |
578 | * multiple. | |
579 | */ | |
46a64376 | 580 | #define MOD_EXP_CTIME_ALIGN(x_) \ |
0f113f3e MC |
581 | ((unsigned char*)(x_) + (MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH - (((size_t)(x_)) & (MOD_EXP_CTIME_MIN_CACHE_LINE_MASK)))) |
582 | ||
583 | /* | |
584 | * This variant of BN_mod_exp_mont() uses fixed windows and the special | |
585 | * precomputation memory layout to limit data-dependency to a minimum to | |
586 | * protect secret exponents (cf. the hyper-threading timing attacks pointed | |
587 | * out by Colin Percival, | |
79caf5d3 | 588 | * http://www.daemonology.net/hyperthreading-considered-harmful/) |
46a64376 BM |
589 | */ |
590 | int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p, | |
0f113f3e MC |
591 | const BIGNUM *m, BN_CTX *ctx, |
592 | BN_MONT_CTX *in_mont) | |
593 | { | |
848113a3 | 594 | int i, bits, ret = 0, window, wvalue, wmask, window0; |
0f113f3e MC |
595 | int top; |
596 | BN_MONT_CTX *mont = NULL; | |
597 | ||
598 | int numPowers; | |
599 | unsigned char *powerbufFree = NULL; | |
600 | int powerbufLen = 0; | |
601 | unsigned char *powerbuf = NULL; | |
602 | BIGNUM tmp, am; | |
cbce8c46 | 603 | #if defined(SPARC_T4_MONT) |
0f113f3e | 604 | unsigned int t4 = 0; |
68c06bf6 | 605 | #endif |
46a64376 | 606 | |
0f113f3e MC |
607 | bn_check_top(a); |
608 | bn_check_top(p); | |
609 | bn_check_top(m); | |
610 | ||
a9009e51 | 611 | if (!BN_is_odd(m)) { |
9311d0c4 | 612 | ERR_raise(ERR_LIB_BN, BN_R_CALLED_WITH_EVEN_MODULUS); |
26a7d938 | 613 | return 0; |
0f113f3e | 614 | } |
a9009e51 EK |
615 | |
616 | top = m->top; | |
617 | ||
39eeb64f DB |
618 | /* |
619 | * Use all bits stored in |p|, rather than |BN_num_bits|, so we do not leak | |
620 | * whether the top bits are zero. | |
621 | */ | |
622 | bits = p->top * BN_BITS2; | |
0f113f3e | 623 | if (bits == 0) { |
4aa5b725 MC |
624 | /* x**0 mod 1, or x**0 mod -1 is still zero. */ |
625 | if (BN_abs_is_word(m, 1)) { | |
d911097d EK |
626 | ret = 1; |
627 | BN_zero(rr); | |
628 | } else { | |
629 | ret = BN_one(rr); | |
630 | } | |
0f113f3e MC |
631 | return ret; |
632 | } | |
633 | ||
634 | BN_CTX_start(ctx); | |
635 | ||
636 | /* | |
637 | * Allocate a montgomery context if it was not supplied by the caller. If | |
638 | * this is not done, things will break in the montgomery part. | |
639 | */ | |
640 | if (in_mont != NULL) | |
641 | mont = in_mont; | |
642 | else { | |
643 | if ((mont = BN_MONT_CTX_new()) == NULL) | |
644 | goto err; | |
645 | if (!BN_MONT_CTX_set(mont, m, ctx)) | |
646 | goto err; | |
647 | } | |
46a64376 | 648 | |
3afd537a DB |
649 | if (a->neg || BN_ucmp(a, m) >= 0) { |
650 | BIGNUM *reduced = BN_CTX_get(ctx); | |
651 | if (reduced == NULL | |
652 | || !BN_nnmod(reduced, a, m, ctx)) { | |
653 | goto err; | |
654 | } | |
655 | a = reduced; | |
656 | } | |
657 | ||
ca48ace5 | 658 | #ifdef RSAZ_ENABLED |
3afd537a DB |
659 | /* |
660 | * If the size of the operands allow it, perform the optimized | |
661 | * RSAZ exponentiation. For further information see | |
662 | * crypto/bn/rsaz_exp.c and accompanying assembly modules. | |
663 | */ | |
664 | if ((16 == a->top) && (16 == p->top) && (BN_num_bits(m) == 1024) | |
665 | && rsaz_avx2_eligible()) { | |
666 | if (NULL == bn_wexpand(rr, 16)) | |
0f113f3e | 667 | goto err; |
3afd537a DB |
668 | RSAZ_1024_mod_exp_avx2(rr->d, a->d, p->d, m->d, mont->RR.d, |
669 | mont->n0[0]); | |
670 | rr->top = 16; | |
671 | rr->neg = 0; | |
672 | bn_correct_top(rr); | |
673 | ret = 1; | |
674 | goto err; | |
675 | } else if ((8 == a->top) && (8 == p->top) && (BN_num_bits(m) == 512)) { | |
676 | if (NULL == bn_wexpand(rr, 8)) | |
0f113f3e | 677 | goto err; |
3afd537a DB |
678 | RSAZ_512_mod_exp(rr->d, a->d, p->d, m->d, mont->n0[0], mont->RR.d); |
679 | rr->top = 8; | |
680 | rr->neg = 0; | |
681 | bn_correct_top(rr); | |
682 | ret = 1; | |
683 | goto err; | |
0f113f3e | 684 | } |
ca48ace5 AP |
685 | #endif |
686 | ||
0f113f3e MC |
687 | /* Get the window size to use with size of p. */ |
688 | window = BN_window_bits_for_ctime_exponent_size(bits); | |
cbce8c46 | 689 | #if defined(SPARC_T4_MONT) |
0f113f3e MC |
690 | if (window >= 5 && (top & 15) == 0 && top <= 64 && |
691 | (OPENSSL_sparcv9cap_P[1] & (CFR_MONTMUL | CFR_MONTSQR)) == | |
692 | (CFR_MONTMUL | CFR_MONTSQR) && (t4 = OPENSSL_sparcv9cap_P[0])) | |
693 | window = 5; | |
694 | else | |
68c06bf6 | 695 | #endif |
361512da | 696 | #if defined(OPENSSL_BN_ASM_MONT5) |
0f113f3e MC |
697 | if (window >= 5) { |
698 | window = 5; /* ~5% improvement for RSA2048 sign, and even | |
699 | * for RSA4096 */ | |
8fc8f486 AP |
700 | /* reserve space for mont->N.d[] copy */ |
701 | powerbufLen += top * sizeof(mont->N.d[0]); | |
0f113f3e | 702 | } |
361512da | 703 | #endif |
0f113f3e MC |
704 | (void)0; |
705 | ||
706 | /* | |
707 | * Allocate a buffer large enough to hold all of the pre-computed powers | |
708 | * of am, am itself and tmp. | |
709 | */ | |
710 | numPowers = 1 << window; | |
711 | powerbufLen += sizeof(m->d[0]) * (top * numPowers + | |
712 | ((2 * top) > | |
713 | numPowers ? (2 * top) : numPowers)); | |
cfdbff23 | 714 | #ifdef alloca |
0f113f3e MC |
715 | if (powerbufLen < 3072) |
716 | powerbufFree = | |
717 | alloca(powerbufLen + MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH); | |
718 | else | |
cfdbff23 | 719 | #endif |
0f113f3e | 720 | if ((powerbufFree = |
b196e7d9 | 721 | OPENSSL_malloc(powerbufLen + MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH)) |
0f113f3e MC |
722 | == NULL) |
723 | goto err; | |
724 | ||
725 | powerbuf = MOD_EXP_CTIME_ALIGN(powerbufFree); | |
726 | memset(powerbuf, 0, powerbufLen); | |
46a64376 | 727 | |
cfdbff23 | 728 | #ifdef alloca |
0f113f3e MC |
729 | if (powerbufLen < 3072) |
730 | powerbufFree = NULL; | |
cfdbff23 | 731 | #endif |
361512da | 732 | |
0f113f3e MC |
733 | /* lay down tmp and am right after powers table */ |
734 | tmp.d = (BN_ULONG *)(powerbuf + sizeof(m->d[0]) * top * numPowers); | |
735 | am.d = tmp.d + top; | |
736 | tmp.top = am.top = 0; | |
737 | tmp.dmax = am.dmax = top; | |
738 | tmp.neg = am.neg = 0; | |
739 | tmp.flags = am.flags = BN_FLG_STATIC_DATA; | |
740 | ||
741 | /* prepare a^0 in Montgomery domain */ | |
742 | #if 1 /* by Shay Gueron's suggestion */ | |
743 | if (m->d[top - 1] & (((BN_ULONG)1) << (BN_BITS2 - 1))) { | |
744 | /* 2^(top*BN_BITS2) - m */ | |
745 | tmp.d[0] = (0 - m->d[0]) & BN_MASK2; | |
746 | for (i = 1; i < top; i++) | |
747 | tmp.d[i] = (~m->d[i]) & BN_MASK2; | |
748 | tmp.top = top; | |
749 | } else | |
8329e2e7 | 750 | #endif |
71883868 | 751 | if (!bn_to_mont_fixed_top(&tmp, BN_value_one(), mont, ctx)) |
0f113f3e MC |
752 | goto err; |
753 | ||
754 | /* prepare a^1 in Montgomery domain */ | |
3afd537a | 755 | if (!bn_to_mont_fixed_top(&am, a, mont, ctx)) |
0f113f3e | 756 | goto err; |
361512da | 757 | |
cbce8c46 | 758 | #if defined(SPARC_T4_MONT) |
0f113f3e MC |
759 | if (t4) { |
760 | typedef int (*bn_pwr5_mont_f) (BN_ULONG *tp, const BN_ULONG *np, | |
761 | const BN_ULONG *n0, const void *table, | |
762 | int power, int bits); | |
763 | int bn_pwr5_mont_t4_8(BN_ULONG *tp, const BN_ULONG *np, | |
764 | const BN_ULONG *n0, const void *table, | |
765 | int power, int bits); | |
766 | int bn_pwr5_mont_t4_16(BN_ULONG *tp, const BN_ULONG *np, | |
767 | const BN_ULONG *n0, const void *table, | |
768 | int power, int bits); | |
769 | int bn_pwr5_mont_t4_24(BN_ULONG *tp, const BN_ULONG *np, | |
770 | const BN_ULONG *n0, const void *table, | |
771 | int power, int bits); | |
772 | int bn_pwr5_mont_t4_32(BN_ULONG *tp, const BN_ULONG *np, | |
773 | const BN_ULONG *n0, const void *table, | |
774 | int power, int bits); | |
775 | static const bn_pwr5_mont_f pwr5_funcs[4] = { | |
776 | bn_pwr5_mont_t4_8, bn_pwr5_mont_t4_16, | |
777 | bn_pwr5_mont_t4_24, bn_pwr5_mont_t4_32 | |
778 | }; | |
779 | bn_pwr5_mont_f pwr5_worker = pwr5_funcs[top / 16 - 1]; | |
780 | ||
781 | typedef int (*bn_mul_mont_f) (BN_ULONG *rp, const BN_ULONG *ap, | |
782 | const void *bp, const BN_ULONG *np, | |
783 | const BN_ULONG *n0); | |
784 | int bn_mul_mont_t4_8(BN_ULONG *rp, const BN_ULONG *ap, const void *bp, | |
785 | const BN_ULONG *np, const BN_ULONG *n0); | |
786 | int bn_mul_mont_t4_16(BN_ULONG *rp, const BN_ULONG *ap, | |
787 | const void *bp, const BN_ULONG *np, | |
788 | const BN_ULONG *n0); | |
789 | int bn_mul_mont_t4_24(BN_ULONG *rp, const BN_ULONG *ap, | |
790 | const void *bp, const BN_ULONG *np, | |
791 | const BN_ULONG *n0); | |
792 | int bn_mul_mont_t4_32(BN_ULONG *rp, const BN_ULONG *ap, | |
793 | const void *bp, const BN_ULONG *np, | |
794 | const BN_ULONG *n0); | |
795 | static const bn_mul_mont_f mul_funcs[4] = { | |
796 | bn_mul_mont_t4_8, bn_mul_mont_t4_16, | |
797 | bn_mul_mont_t4_24, bn_mul_mont_t4_32 | |
798 | }; | |
799 | bn_mul_mont_f mul_worker = mul_funcs[top / 16 - 1]; | |
800 | ||
801 | void bn_mul_mont_vis3(BN_ULONG *rp, const BN_ULONG *ap, | |
802 | const void *bp, const BN_ULONG *np, | |
803 | const BN_ULONG *n0, int num); | |
804 | void bn_mul_mont_t4(BN_ULONG *rp, const BN_ULONG *ap, | |
805 | const void *bp, const BN_ULONG *np, | |
806 | const BN_ULONG *n0, int num); | |
807 | void bn_mul_mont_gather5_t4(BN_ULONG *rp, const BN_ULONG *ap, | |
808 | const void *table, const BN_ULONG *np, | |
809 | const BN_ULONG *n0, int num, int power); | |
810 | void bn_flip_n_scatter5_t4(const BN_ULONG *inp, size_t num, | |
811 | void *table, size_t power); | |
812 | void bn_gather5_t4(BN_ULONG *out, size_t num, | |
813 | void *table, size_t power); | |
814 | void bn_flip_t4(BN_ULONG *dst, BN_ULONG *src, size_t num); | |
815 | ||
816 | BN_ULONG *np = mont->N.d, *n0 = mont->n0; | |
817 | int stride = 5 * (6 - (top / 16 - 1)); /* multiple of 5, but less | |
818 | * than 32 */ | |
819 | ||
820 | /* | |
821 | * BN_to_montgomery can contaminate words above .top [in | |
822 | * BN_DEBUG[_DEBUG] build]... | |
823 | */ | |
824 | for (i = am.top; i < top; i++) | |
825 | am.d[i] = 0; | |
826 | for (i = tmp.top; i < top; i++) | |
827 | tmp.d[i] = 0; | |
828 | ||
829 | bn_flip_n_scatter5_t4(tmp.d, top, powerbuf, 0); | |
830 | bn_flip_n_scatter5_t4(am.d, top, powerbuf, 1); | |
831 | if (!(*mul_worker) (tmp.d, am.d, am.d, np, n0) && | |
832 | !(*mul_worker) (tmp.d, am.d, am.d, np, n0)) | |
833 | bn_mul_mont_vis3(tmp.d, am.d, am.d, np, n0, top); | |
834 | bn_flip_n_scatter5_t4(tmp.d, top, powerbuf, 2); | |
835 | ||
836 | for (i = 3; i < 32; i++) { | |
837 | /* Calculate a^i = a^(i-1) * a */ | |
838 | if (!(*mul_worker) (tmp.d, tmp.d, am.d, np, n0) && | |
839 | !(*mul_worker) (tmp.d, tmp.d, am.d, np, n0)) | |
840 | bn_mul_mont_vis3(tmp.d, tmp.d, am.d, np, n0, top); | |
841 | bn_flip_n_scatter5_t4(tmp.d, top, powerbuf, i); | |
842 | } | |
843 | ||
844 | /* switch to 64-bit domain */ | |
845 | np = alloca(top * sizeof(BN_ULONG)); | |
846 | top /= 2; | |
847 | bn_flip_t4(np, mont->N.d, top); | |
848 | ||
3f0c3d22 AP |
849 | /* |
850 | * The exponent may not have a whole number of fixed-size windows. | |
851 | * To simplify the main loop, the initial window has between 1 and | |
852 | * full-window-size bits such that what remains is always a whole | |
853 | * number of windows | |
854 | */ | |
855 | window0 = (bits - 1) % 5 + 1; | |
856 | wmask = (1 << window0) - 1; | |
857 | bits -= window0; | |
858 | wvalue = bn_get_bits(p, bits) & wmask; | |
0f113f3e MC |
859 | bn_gather5_t4(tmp.d, top, powerbuf, wvalue); |
860 | ||
861 | /* | |
862 | * Scan the exponent one window at a time starting from the most | |
863 | * significant bits. | |
864 | */ | |
3f0c3d22 | 865 | while (bits > 0) { |
0f113f3e | 866 | if (bits < stride) |
3f0c3d22 | 867 | stride = bits; |
0f113f3e | 868 | bits -= stride; |
3f0c3d22 | 869 | wvalue = bn_get_bits(p, bits); |
0f113f3e MC |
870 | |
871 | if ((*pwr5_worker) (tmp.d, np, n0, powerbuf, wvalue, stride)) | |
872 | continue; | |
873 | /* retry once and fall back */ | |
874 | if ((*pwr5_worker) (tmp.d, np, n0, powerbuf, wvalue, stride)) | |
875 | continue; | |
876 | ||
877 | bits += stride - 5; | |
878 | wvalue >>= stride - 5; | |
879 | wvalue &= 31; | |
880 | bn_mul_mont_t4(tmp.d, tmp.d, tmp.d, np, n0, top); | |
881 | bn_mul_mont_t4(tmp.d, tmp.d, tmp.d, np, n0, top); | |
882 | bn_mul_mont_t4(tmp.d, tmp.d, tmp.d, np, n0, top); | |
883 | bn_mul_mont_t4(tmp.d, tmp.d, tmp.d, np, n0, top); | |
884 | bn_mul_mont_t4(tmp.d, tmp.d, tmp.d, np, n0, top); | |
885 | bn_mul_mont_gather5_t4(tmp.d, tmp.d, powerbuf, np, n0, top, | |
886 | wvalue); | |
887 | } | |
888 | ||
889 | bn_flip_t4(tmp.d, tmp.d, top); | |
890 | top *= 2; | |
891 | /* back to 32-bit domain */ | |
892 | tmp.top = top; | |
893 | bn_correct_top(&tmp); | |
894 | OPENSSL_cleanse(np, top * sizeof(BN_ULONG)); | |
895 | } else | |
68c06bf6 | 896 | #endif |
361512da | 897 | #if defined(OPENSSL_BN_ASM_MONT5) |
0f113f3e MC |
898 | if (window == 5 && top > 1) { |
899 | /* | |
900 | * This optimization uses ideas from http://eprint.iacr.org/2011/239, | |
901 | * specifically optimization of cache-timing attack countermeasures | |
902 | * and pre-computation optimization. | |
903 | */ | |
904 | ||
905 | /* | |
906 | * Dedicated window==4 case improves 512-bit RSA sign by ~15%, but as | |
907 | * 512-bit RSA is hardly relevant, we omit it to spare size... | |
908 | */ | |
909 | void bn_mul_mont_gather5(BN_ULONG *rp, const BN_ULONG *ap, | |
910 | const void *table, const BN_ULONG *np, | |
911 | const BN_ULONG *n0, int num, int power); | |
912 | void bn_scatter5(const BN_ULONG *inp, size_t num, | |
913 | void *table, size_t power); | |
914 | void bn_gather5(BN_ULONG *out, size_t num, void *table, size_t power); | |
915 | void bn_power5(BN_ULONG *rp, const BN_ULONG *ap, | |
916 | const void *table, const BN_ULONG *np, | |
917 | const BN_ULONG *n0, int num, int power); | |
918 | int bn_get_bits5(const BN_ULONG *ap, int off); | |
919 | int bn_from_montgomery(BN_ULONG *rp, const BN_ULONG *ap, | |
920 | const BN_ULONG *not_used, const BN_ULONG *np, | |
921 | const BN_ULONG *n0, int num); | |
922 | ||
8fc8f486 | 923 | BN_ULONG *n0 = mont->n0, *np; |
0f113f3e MC |
924 | |
925 | /* | |
926 | * BN_to_montgomery can contaminate words above .top [in | |
927 | * BN_DEBUG[_DEBUG] build]... | |
928 | */ | |
929 | for (i = am.top; i < top; i++) | |
930 | am.d[i] = 0; | |
931 | for (i = tmp.top; i < top; i++) | |
932 | tmp.d[i] = 0; | |
933 | ||
8fc8f486 AP |
934 | /* |
935 | * copy mont->N.d[] to improve cache locality | |
936 | */ | |
937 | for (np = am.d + top, i = 0; i < top; i++) | |
938 | np[i] = mont->N.d[i]; | |
0f113f3e MC |
939 | |
940 | bn_scatter5(tmp.d, top, powerbuf, 0); | |
941 | bn_scatter5(am.d, am.top, powerbuf, 1); | |
942 | bn_mul_mont(tmp.d, am.d, am.d, np, n0, top); | |
943 | bn_scatter5(tmp.d, top, powerbuf, 2); | |
944 | ||
945 | # if 0 | |
946 | for (i = 3; i < 32; i++) { | |
947 | /* Calculate a^i = a^(i-1) * a */ | |
8fc8f486 | 948 | bn_mul_mont_gather5(tmp.d, am.d, powerbuf, np, n0, top, i - 1); |
0f113f3e MC |
949 | bn_scatter5(tmp.d, top, powerbuf, i); |
950 | } | |
951 | # else | |
952 | /* same as above, but uses squaring for 1/2 of operations */ | |
953 | for (i = 4; i < 32; i *= 2) { | |
954 | bn_mul_mont(tmp.d, tmp.d, tmp.d, np, n0, top); | |
955 | bn_scatter5(tmp.d, top, powerbuf, i); | |
956 | } | |
957 | for (i = 3; i < 8; i += 2) { | |
958 | int j; | |
8fc8f486 | 959 | bn_mul_mont_gather5(tmp.d, am.d, powerbuf, np, n0, top, i - 1); |
0f113f3e MC |
960 | bn_scatter5(tmp.d, top, powerbuf, i); |
961 | for (j = 2 * i; j < 32; j *= 2) { | |
962 | bn_mul_mont(tmp.d, tmp.d, tmp.d, np, n0, top); | |
963 | bn_scatter5(tmp.d, top, powerbuf, j); | |
964 | } | |
965 | } | |
966 | for (; i < 16; i += 2) { | |
8fc8f486 | 967 | bn_mul_mont_gather5(tmp.d, am.d, powerbuf, np, n0, top, i - 1); |
0f113f3e MC |
968 | bn_scatter5(tmp.d, top, powerbuf, i); |
969 | bn_mul_mont(tmp.d, tmp.d, tmp.d, np, n0, top); | |
970 | bn_scatter5(tmp.d, top, powerbuf, 2 * i); | |
971 | } | |
972 | for (; i < 32; i += 2) { | |
8fc8f486 | 973 | bn_mul_mont_gather5(tmp.d, am.d, powerbuf, np, n0, top, i - 1); |
0f113f3e MC |
974 | bn_scatter5(tmp.d, top, powerbuf, i); |
975 | } | |
976 | # endif | |
3f0c3d22 AP |
977 | /* |
978 | * The exponent may not have a whole number of fixed-size windows. | |
979 | * To simplify the main loop, the initial window has between 1 and | |
980 | * full-window-size bits such that what remains is always a whole | |
981 | * number of windows | |
982 | */ | |
983 | window0 = (bits - 1) % 5 + 1; | |
984 | wmask = (1 << window0) - 1; | |
985 | bits -= window0; | |
986 | wvalue = bn_get_bits(p, bits) & wmask; | |
0f113f3e MC |
987 | bn_gather5(tmp.d, top, powerbuf, wvalue); |
988 | ||
989 | /* | |
990 | * Scan the exponent one window at a time starting from the most | |
991 | * significant bits. | |
992 | */ | |
3f0c3d22 AP |
993 | if (top & 7) { |
994 | while (bits > 0) { | |
0f113f3e MC |
995 | bn_mul_mont(tmp.d, tmp.d, tmp.d, np, n0, top); |
996 | bn_mul_mont(tmp.d, tmp.d, tmp.d, np, n0, top); | |
997 | bn_mul_mont(tmp.d, tmp.d, tmp.d, np, n0, top); | |
998 | bn_mul_mont(tmp.d, tmp.d, tmp.d, np, n0, top); | |
999 | bn_mul_mont(tmp.d, tmp.d, tmp.d, np, n0, top); | |
1000 | bn_mul_mont_gather5(tmp.d, tmp.d, powerbuf, np, n0, top, | |
3f0c3d22 AP |
1001 | bn_get_bits5(p->d, bits -= 5)); |
1002 | } | |
0f113f3e | 1003 | } else { |
3f0c3d22 AP |
1004 | while (bits > 0) { |
1005 | bn_power5(tmp.d, tmp.d, powerbuf, np, n0, top, | |
1006 | bn_get_bits5(p->d, bits -= 5)); | |
0f113f3e MC |
1007 | } |
1008 | } | |
1009 | ||
8fc8f486 | 1010 | ret = bn_from_montgomery(tmp.d, tmp.d, NULL, np, n0, top); |
0f113f3e MC |
1011 | tmp.top = top; |
1012 | bn_correct_top(&tmp); | |
1013 | if (ret) { | |
1014 | if (!BN_copy(rr, &tmp)) | |
1015 | ret = 0; | |
1016 | goto err; /* non-zero ret means it's not error */ | |
1017 | } | |
1018 | } else | |
361512da | 1019 | #endif |
0f113f3e | 1020 | { |
d6482a82 | 1021 | if (!MOD_EXP_CTIME_COPY_TO_PREBUF(&tmp, top, powerbuf, 0, window)) |
0f113f3e | 1022 | goto err; |
d6482a82 | 1023 | if (!MOD_EXP_CTIME_COPY_TO_PREBUF(&am, top, powerbuf, 1, window)) |
0f113f3e MC |
1024 | goto err; |
1025 | ||
1026 | /* | |
1027 | * If the window size is greater than 1, then calculate | |
1028 | * val[i=2..2^winsize-1]. Powers are computed as a*a^(i-1) (even | |
1029 | * powers could instead be computed as (a^(i/2))^2 to use the slight | |
1030 | * performance advantage of sqr over mul). | |
1031 | */ | |
1032 | if (window > 1) { | |
71883868 | 1033 | if (!bn_mul_mont_fixed_top(&tmp, &am, &am, mont, ctx)) |
0f113f3e | 1034 | goto err; |
d6482a82 AP |
1035 | if (!MOD_EXP_CTIME_COPY_TO_PREBUF(&tmp, top, powerbuf, 2, |
1036 | window)) | |
0f113f3e MC |
1037 | goto err; |
1038 | for (i = 3; i < numPowers; i++) { | |
1039 | /* Calculate a^i = a^(i-1) * a */ | |
71883868 | 1040 | if (!bn_mul_mont_fixed_top(&tmp, &am, &tmp, mont, ctx)) |
0f113f3e | 1041 | goto err; |
d6482a82 AP |
1042 | if (!MOD_EXP_CTIME_COPY_TO_PREBUF(&tmp, top, powerbuf, i, |
1043 | window)) | |
0f113f3e MC |
1044 | goto err; |
1045 | } | |
1046 | } | |
1047 | ||
3f0c3d22 | 1048 | /* |
848113a3 U |
1049 | * The exponent may not have a whole number of fixed-size windows. |
1050 | * To simplify the main loop, the initial window has between 1 and | |
1051 | * full-window-size bits such that what remains is always a whole | |
1052 | * number of windows | |
3f0c3d22 | 1053 | */ |
848113a3 U |
1054 | window0 = (bits - 1) % window + 1; |
1055 | wmask = (1 << window0) - 1; | |
1056 | bits -= window0; | |
1057 | wvalue = bn_get_bits(p, bits) & wmask; | |
d6482a82 AP |
1058 | if (!MOD_EXP_CTIME_COPY_FROM_PREBUF(&tmp, top, powerbuf, wvalue, |
1059 | window)) | |
0f113f3e MC |
1060 | goto err; |
1061 | ||
848113a3 | 1062 | wmask = (1 << window) - 1; |
0f113f3e MC |
1063 | /* |
1064 | * Scan the exponent one window at a time starting from the most | |
1065 | * significant bits. | |
1066 | */ | |
848113a3 | 1067 | while (bits > 0) { |
0f113f3e | 1068 | |
848113a3 U |
1069 | /* Square the result window-size times */ |
1070 | for (i = 0; i < window; i++) | |
71883868 | 1071 | if (!bn_mul_mont_fixed_top(&tmp, &tmp, &tmp, mont, ctx)) |
0f113f3e | 1072 | goto err; |
0f113f3e | 1073 | |
3f0c3d22 | 1074 | /* |
848113a3 U |
1075 | * Get a window's worth of bits from the exponent |
1076 | * This avoids calling BN_is_bit_set for each bit, which | |
1077 | * is not only slower but also makes each bit vulnerable to | |
1078 | * EM (and likely other) side-channel attacks like One&Done | |
1079 | * (for details see "One&Done: A Single-Decryption EM-Based | |
cf4eea12 | 1080 | * Attack on OpenSSL's Constant-Time Blinded RSA" by M. Alam, |
848113a3 U |
1081 | * H. Khan, M. Dey, N. Sinha, R. Callan, A. Zajic, and |
1082 | * M. Prvulovic, in USENIX Security'18) | |
1083 | */ | |
1084 | bits -= window; | |
1085 | wvalue = bn_get_bits(p, bits) & wmask; | |
0f113f3e MC |
1086 | /* |
1087 | * Fetch the appropriate pre-computed value from the pre-buf | |
1088 | */ | |
d6482a82 AP |
1089 | if (!MOD_EXP_CTIME_COPY_FROM_PREBUF(&am, top, powerbuf, wvalue, |
1090 | window)) | |
0f113f3e MC |
1091 | goto err; |
1092 | ||
1093 | /* Multiply the result into the intermediate result */ | |
71883868 | 1094 | if (!bn_mul_mont_fixed_top(&tmp, &tmp, &am, mont, ctx)) |
0f113f3e MC |
1095 | goto err; |
1096 | } | |
1097 | } | |
1098 | ||
71883868 AP |
1099 | /* |
1100 | * Done with zero-padded intermediate BIGNUMs. Final BN_from_montgomery | |
1101 | * removes padding [if any] and makes return value suitable for public | |
1102 | * API consumer. | |
1103 | */ | |
cbce8c46 | 1104 | #if defined(SPARC_T4_MONT) |
0f113f3e MC |
1105 | if (OPENSSL_sparcv9cap_P[0] & (SPARCV9_VIS3 | SPARCV9_PREFER_FPU)) { |
1106 | am.d[0] = 1; /* borrow am */ | |
1107 | for (i = 1; i < top; i++) | |
1108 | am.d[i] = 0; | |
1109 | if (!BN_mod_mul_montgomery(rr, &tmp, &am, mont, ctx)) | |
1110 | goto err; | |
1111 | } else | |
4ddacd99 | 1112 | #endif |
0f113f3e MC |
1113 | if (!BN_from_montgomery(rr, &tmp, mont, ctx)) |
1114 | goto err; | |
1115 | ret = 1; | |
1116 | err: | |
23a1d5e9 | 1117 | if (in_mont == NULL) |
0f113f3e MC |
1118 | BN_MONT_CTX_free(mont); |
1119 | if (powerbuf != NULL) { | |
1120 | OPENSSL_cleanse(powerbuf, powerbufLen); | |
b548a1f1 | 1121 | OPENSSL_free(powerbufFree); |
0f113f3e MC |
1122 | } |
1123 | BN_CTX_end(ctx); | |
26a7d938 | 1124 | return ret; |
0f113f3e | 1125 | } |
46a64376 | 1126 | |
6dad7bd6 BM |
1127 | int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p, |
1128 | const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont) | |
0f113f3e MC |
1129 | { |
1130 | BN_MONT_CTX *mont = NULL; | |
1131 | int b, bits, ret = 0; | |
1132 | int r_is_one; | |
1133 | BN_ULONG w, next_w; | |
edea42c6 | 1134 | BIGNUM *r, *t; |
0f113f3e | 1135 | BIGNUM *swap_tmp; |
f8989a21 | 1136 | #define BN_MOD_MUL_WORD(r, w, m) \ |
0f113f3e MC |
1137 | (BN_mul_word(r, (w)) && \ |
1138 | (/* BN_ucmp(r, (m)) < 0 ? 1 :*/ \ | |
1139 | (BN_mod(t, r, m, ctx) && (swap_tmp = r, r = t, t = swap_tmp, 1)))) | |
1140 | /* | |
1141 | * BN_MOD_MUL_WORD is only used with 'w' large, so the BN_ucmp test is | |
1142 | * probably more overhead than always using BN_mod (which uses BN_copy if | |
1143 | * a similar test returns true). | |
1144 | */ | |
1145 | /* | |
1146 | * We can use BN_mod and do not need BN_nnmod because our accumulator is | |
1147 | * never negative (the result of BN_mod does not depend on the sign of | |
1148 | * the modulus). | |
1149 | */ | |
e958c5af | 1150 | #define BN_TO_MONTGOMERY_WORD(r, w, mont) \ |
0f113f3e MC |
1151 | (BN_set_word(r, (w)) && BN_to_montgomery(r, r, (mont), ctx)) |
1152 | ||
e913d11f MC |
1153 | if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0 |
1154 | || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) { | |
0f113f3e | 1155 | /* BN_FLG_CONSTTIME only supported by BN_mod_exp_mont() */ |
9311d0c4 | 1156 | ERR_raise(ERR_LIB_BN, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); |
0818dbad | 1157 | return 0; |
0f113f3e MC |
1158 | } |
1159 | ||
1160 | bn_check_top(p); | |
1161 | bn_check_top(m); | |
1162 | ||
1163 | if (!BN_is_odd(m)) { | |
9311d0c4 | 1164 | ERR_raise(ERR_LIB_BN, BN_R_CALLED_WITH_EVEN_MODULUS); |
26a7d938 | 1165 | return 0; |
0f113f3e MC |
1166 | } |
1167 | if (m->top == 1) | |
1168 | a %= m->d[0]; /* make sure that 'a' is reduced */ | |
1169 | ||
1170 | bits = BN_num_bits(p); | |
1171 | if (bits == 0) { | |
4aa5b725 MC |
1172 | /* x**0 mod 1, or x**0 mod -1 is still zero. */ |
1173 | if (BN_abs_is_word(m, 1)) { | |
0f113f3e MC |
1174 | ret = 1; |
1175 | BN_zero(rr); | |
d911097d | 1176 | } else { |
0f113f3e | 1177 | ret = BN_one(rr); |
d911097d | 1178 | } |
0f113f3e MC |
1179 | return ret; |
1180 | } | |
1181 | if (a == 0) { | |
1182 | BN_zero(rr); | |
1183 | ret = 1; | |
1184 | return ret; | |
1185 | } | |
1186 | ||
1187 | BN_CTX_start(ctx); | |
0f113f3e MC |
1188 | r = BN_CTX_get(ctx); |
1189 | t = BN_CTX_get(ctx); | |
edea42c6 | 1190 | if (t == NULL) |
0f113f3e MC |
1191 | goto err; |
1192 | ||
1193 | if (in_mont != NULL) | |
1194 | mont = in_mont; | |
1195 | else { | |
1196 | if ((mont = BN_MONT_CTX_new()) == NULL) | |
1197 | goto err; | |
1198 | if (!BN_MONT_CTX_set(mont, m, ctx)) | |
1199 | goto err; | |
1200 | } | |
1201 | ||
1202 | r_is_one = 1; /* except for Montgomery factor */ | |
1203 | ||
1204 | /* bits-1 >= 0 */ | |
1205 | ||
1206 | /* The result is accumulated in the product r*w. */ | |
1207 | w = a; /* bit 'bits-1' of 'p' is always set */ | |
1208 | for (b = bits - 2; b >= 0; b--) { | |
1209 | /* First, square r*w. */ | |
1210 | next_w = w * w; | |
1211 | if ((next_w / w) != w) { /* overflow */ | |
1212 | if (r_is_one) { | |
1213 | if (!BN_TO_MONTGOMERY_WORD(r, w, mont)) | |
1214 | goto err; | |
1215 | r_is_one = 0; | |
1216 | } else { | |
1217 | if (!BN_MOD_MUL_WORD(r, w, m)) | |
1218 | goto err; | |
1219 | } | |
1220 | next_w = 1; | |
1221 | } | |
1222 | w = next_w; | |
1223 | if (!r_is_one) { | |
1224 | if (!BN_mod_mul_montgomery(r, r, r, mont, ctx)) | |
1225 | goto err; | |
1226 | } | |
1227 | ||
1228 | /* Second, multiply r*w by 'a' if exponent bit is set. */ | |
1229 | if (BN_is_bit_set(p, b)) { | |
1230 | next_w = w * a; | |
1231 | if ((next_w / a) != w) { /* overflow */ | |
1232 | if (r_is_one) { | |
1233 | if (!BN_TO_MONTGOMERY_WORD(r, w, mont)) | |
1234 | goto err; | |
1235 | r_is_one = 0; | |
1236 | } else { | |
1237 | if (!BN_MOD_MUL_WORD(r, w, m)) | |
1238 | goto err; | |
1239 | } | |
1240 | next_w = a; | |
1241 | } | |
1242 | w = next_w; | |
1243 | } | |
1244 | } | |
1245 | ||
1246 | /* Finally, set r:=r*w. */ | |
1247 | if (w != 1) { | |
1248 | if (r_is_one) { | |
1249 | if (!BN_TO_MONTGOMERY_WORD(r, w, mont)) | |
1250 | goto err; | |
1251 | r_is_one = 0; | |
1252 | } else { | |
1253 | if (!BN_MOD_MUL_WORD(r, w, m)) | |
1254 | goto err; | |
1255 | } | |
1256 | } | |
1257 | ||
1258 | if (r_is_one) { /* can happen only if a == 1 */ | |
1259 | if (!BN_one(rr)) | |
1260 | goto err; | |
1261 | } else { | |
1262 | if (!BN_from_montgomery(rr, r, mont, ctx)) | |
1263 | goto err; | |
1264 | } | |
1265 | ret = 1; | |
1266 | err: | |
23a1d5e9 | 1267 | if (in_mont == NULL) |
0f113f3e MC |
1268 | BN_MONT_CTX_free(mont); |
1269 | BN_CTX_end(ctx); | |
1270 | bn_check_top(rr); | |
26a7d938 | 1271 | return ret; |
0f113f3e | 1272 | } |
d02b48c6 RE |
1273 | |
1274 | /* The old fallback, simple version :-) */ | |
82b2f57e | 1275 | int BN_mod_exp_simple(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, |
0f113f3e MC |
1276 | const BIGNUM *m, BN_CTX *ctx) |
1277 | { | |
1278 | int i, j, bits, ret = 0, wstart, wend, window, wvalue; | |
1279 | int start = 1; | |
1280 | BIGNUM *d; | |
1281 | /* Table of variables obtained from 'ctx' */ | |
1282 | BIGNUM *val[TABLE_SIZE]; | |
1283 | ||
e913d11f MC |
1284 | if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0 |
1285 | || BN_get_flags(a, BN_FLG_CONSTTIME) != 0 | |
1286 | || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) { | |
0f113f3e | 1287 | /* BN_FLG_CONSTTIME only supported by BN_mod_exp_mont() */ |
9311d0c4 | 1288 | ERR_raise(ERR_LIB_BN, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); |
0818dbad | 1289 | return 0; |
0f113f3e MC |
1290 | } |
1291 | ||
1292 | bits = BN_num_bits(p); | |
c1ec4db3 | 1293 | if (bits == 0) { |
4aa5b725 MC |
1294 | /* x**0 mod 1, or x**0 mod -1 is still zero. */ |
1295 | if (BN_abs_is_word(m, 1)) { | |
d911097d EK |
1296 | ret = 1; |
1297 | BN_zero(r); | |
1298 | } else { | |
1299 | ret = BN_one(r); | |
1300 | } | |
0f113f3e MC |
1301 | return ret; |
1302 | } | |
1303 | ||
1304 | BN_CTX_start(ctx); | |
1305 | d = BN_CTX_get(ctx); | |
1306 | val[0] = BN_CTX_get(ctx); | |
edea42c6 | 1307 | if (val[0] == NULL) |
0f113f3e MC |
1308 | goto err; |
1309 | ||
1310 | if (!BN_nnmod(val[0], a, m, ctx)) | |
1311 | goto err; /* 1 */ | |
1312 | if (BN_is_zero(val[0])) { | |
1313 | BN_zero(r); | |
1314 | ret = 1; | |
1315 | goto err; | |
1316 | } | |
1317 | ||
1318 | window = BN_window_bits_for_exponent_size(bits); | |
1319 | if (window > 1) { | |
1320 | if (!BN_mod_mul(d, val[0], val[0], m, ctx)) | |
1321 | goto err; /* 2 */ | |
1322 | j = 1 << (window - 1); | |
1323 | for (i = 1; i < j; i++) { | |
1324 | if (((val[i] = BN_CTX_get(ctx)) == NULL) || | |
1325 | !BN_mod_mul(val[i], val[i - 1], d, m, ctx)) | |
1326 | goto err; | |
1327 | } | |
1328 | } | |
1329 | ||
1330 | start = 1; /* This is used to avoid multiplication etc | |
1331 | * when there is only the value '1' in the | |
1332 | * buffer. */ | |
1333 | wvalue = 0; /* The 'value' of the window */ | |
1334 | wstart = bits - 1; /* The top bit of the window */ | |
1335 | wend = 0; /* The bottom bit of the window */ | |
1336 | ||
1337 | if (!BN_one(r)) | |
1338 | goto err; | |
1339 | ||
1340 | for (;;) { | |
1341 | if (BN_is_bit_set(p, wstart) == 0) { | |
1342 | if (!start) | |
1343 | if (!BN_mod_mul(r, r, r, m, ctx)) | |
1344 | goto err; | |
1345 | if (wstart == 0) | |
1346 | break; | |
1347 | wstart--; | |
1348 | continue; | |
1349 | } | |
1350 | /* | |
1351 | * We now have wstart on a 'set' bit, we now need to work out how bit | |
1352 | * a window to do. To do this we need to scan forward until the last | |
1353 | * set bit before the end of the window | |
1354 | */ | |
0f113f3e MC |
1355 | wvalue = 1; |
1356 | wend = 0; | |
1357 | for (i = 1; i < window; i++) { | |
1358 | if (wstart - i < 0) | |
1359 | break; | |
1360 | if (BN_is_bit_set(p, wstart - i)) { | |
1361 | wvalue <<= (i - wend); | |
1362 | wvalue |= 1; | |
1363 | wend = i; | |
1364 | } | |
1365 | } | |
1366 | ||
1367 | /* wend is the size of the current window */ | |
1368 | j = wend + 1; | |
1369 | /* add the 'bytes above' */ | |
1370 | if (!start) | |
1371 | for (i = 0; i < j; i++) { | |
1372 | if (!BN_mod_mul(r, r, r, m, ctx)) | |
1373 | goto err; | |
1374 | } | |
1375 | ||
1376 | /* wvalue will be an odd number < 2^window */ | |
1377 | if (!BN_mod_mul(r, r, val[wvalue >> 1], m, ctx)) | |
1378 | goto err; | |
1379 | ||
1380 | /* move the 'window' down further */ | |
1381 | wstart -= wend + 1; | |
1382 | wvalue = 0; | |
1383 | start = 0; | |
1384 | if (wstart < 0) | |
1385 | break; | |
1386 | } | |
1387 | ret = 1; | |
1388 | err: | |
1389 | BN_CTX_end(ctx); | |
1390 | bn_check_top(r); | |
26a7d938 | 1391 | return ret; |
0f113f3e | 1392 | } |
c781eb1c AM |
1393 | |
1394 | /* | |
1395 | * This is a variant of modular exponentiation optimization that does | |
1396 | * parallel 2-primes exponentiation using 256-bit (AVX512VL) AVX512_IFMA ISA | |
1397 | * in 52-bit binary redundant representation. | |
1398 | * If such instructions are not available, or input data size is not supported, | |
1399 | * it falls back to two BN_mod_exp_mont_consttime() calls. | |
1400 | */ | |
1401 | int BN_mod_exp_mont_consttime_x2(BIGNUM *rr1, const BIGNUM *a1, const BIGNUM *p1, | |
1402 | const BIGNUM *m1, BN_MONT_CTX *in_mont1, | |
1403 | BIGNUM *rr2, const BIGNUM *a2, const BIGNUM *p2, | |
1404 | const BIGNUM *m2, BN_MONT_CTX *in_mont2, | |
1405 | BN_CTX *ctx) | |
1406 | { | |
1407 | int ret = 0; | |
1408 | ||
1409 | #ifdef RSAZ_ENABLED | |
1410 | BN_MONT_CTX *mont1 = NULL; | |
1411 | BN_MONT_CTX *mont2 = NULL; | |
1412 | ||
1413 | if (rsaz_avx512ifma_eligible() && | |
1414 | ((a1->top == 16) && (p1->top == 16) && (BN_num_bits(m1) == 1024) && | |
1415 | (a2->top == 16) && (p2->top == 16) && (BN_num_bits(m2) == 1024))) { | |
1416 | ||
1417 | if (bn_wexpand(rr1, 16) == NULL) | |
1418 | goto err; | |
1419 | if (bn_wexpand(rr2, 16) == NULL) | |
1420 | goto err; | |
1421 | ||
1422 | /* Ensure that montgomery contexts are initialized */ | |
1423 | if (in_mont1 != NULL) { | |
1424 | mont1 = in_mont1; | |
1425 | } else { | |
1426 | if ((mont1 = BN_MONT_CTX_new()) == NULL) | |
1427 | goto err; | |
1428 | if (!BN_MONT_CTX_set(mont1, m1, ctx)) | |
1429 | goto err; | |
1430 | } | |
1431 | if (in_mont2 != NULL) { | |
1432 | mont2 = in_mont2; | |
1433 | } else { | |
1434 | if ((mont2 = BN_MONT_CTX_new()) == NULL) | |
1435 | goto err; | |
1436 | if (!BN_MONT_CTX_set(mont2, m2, ctx)) | |
1437 | goto err; | |
1438 | } | |
1439 | ||
1440 | ret = RSAZ_mod_exp_avx512_x2(rr1->d, a1->d, p1->d, m1->d, mont1->RR.d, | |
1441 | mont1->n0[0], | |
1442 | rr2->d, a2->d, p2->d, m2->d, mont2->RR.d, | |
1443 | mont2->n0[0], | |
1444 | 1024 /* factor bit size */); | |
1445 | ||
1446 | rr1->top = 16; | |
1447 | rr1->neg = 0; | |
1448 | bn_correct_top(rr1); | |
1449 | bn_check_top(rr1); | |
1450 | ||
1451 | rr2->top = 16; | |
1452 | rr2->neg = 0; | |
1453 | bn_correct_top(rr2); | |
1454 | bn_check_top(rr2); | |
1455 | ||
1456 | goto err; | |
1457 | } | |
1458 | #endif | |
1459 | ||
1460 | /* rr1 = a1^p1 mod m1 */ | |
1461 | ret = BN_mod_exp_mont_consttime(rr1, a1, p1, m1, ctx, in_mont1); | |
1462 | /* rr2 = a2^p2 mod m2 */ | |
1463 | ret &= BN_mod_exp_mont_consttime(rr2, a2, p2, m2, ctx, in_mont2); | |
1464 | ||
1465 | #ifdef RSAZ_ENABLED | |
1466 | err: | |
1467 | if (in_mont2 == NULL) | |
1468 | BN_MONT_CTX_free(mont2); | |
1469 | if (in_mont1 == NULL) | |
1470 | BN_MONT_CTX_free(mont1); | |
1471 | #endif | |
1472 | ||
1473 | return ret; | |
1474 | } |