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58964a49 | 1 | /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) |
d02b48c6 RE |
2 | * All rights reserved. |
3 | * | |
4 | * This package is an SSL implementation written | |
5 | * by Eric Young (eay@cryptsoft.com). | |
6 | * The implementation was written so as to conform with Netscapes SSL. | |
0f113f3e | 7 | * |
d02b48c6 RE |
8 | * This library is free for commercial and non-commercial use as long as |
9 | * the following conditions are aheared to. The following conditions | |
10 | * apply to all code found in this distribution, be it the RC4, RSA, | |
11 | * lhash, DES, etc., code; not just the SSL code. The SSL documentation | |
12 | * included with this distribution is covered by the same copyright terms | |
13 | * except that the holder is Tim Hudson (tjh@cryptsoft.com). | |
0f113f3e | 14 | * |
d02b48c6 RE |
15 | * Copyright remains Eric Young's, and as such any Copyright notices in |
16 | * the code are not to be removed. | |
17 | * If this package is used in a product, Eric Young should be given attribution | |
18 | * as the author of the parts of the library used. | |
19 | * This can be in the form of a textual message at program startup or | |
20 | * in documentation (online or textual) provided with the package. | |
0f113f3e | 21 | * |
d02b48c6 RE |
22 | * Redistribution and use in source and binary forms, with or without |
23 | * modification, are permitted provided that the following conditions | |
24 | * are met: | |
25 | * 1. Redistributions of source code must retain the copyright | |
26 | * notice, this list of conditions and the following disclaimer. | |
27 | * 2. Redistributions in binary form must reproduce the above copyright | |
28 | * notice, this list of conditions and the following disclaimer in the | |
29 | * documentation and/or other materials provided with the distribution. | |
30 | * 3. All advertising materials mentioning features or use of this software | |
31 | * must display the following acknowledgement: | |
32 | * "This product includes cryptographic software written by | |
33 | * Eric Young (eay@cryptsoft.com)" | |
34 | * The word 'cryptographic' can be left out if the rouines from the library | |
35 | * being used are not cryptographic related :-). | |
0f113f3e | 36 | * 4. If you include any Windows specific code (or a derivative thereof) from |
d02b48c6 RE |
37 | * the apps directory (application code) you must include an acknowledgement: |
38 | * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" | |
0f113f3e | 39 | * |
d02b48c6 RE |
40 | * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND |
41 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
42 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
43 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE | |
44 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
45 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
46 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
47 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
48 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
49 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
50 | * SUCH DAMAGE. | |
0f113f3e | 51 | * |
d02b48c6 RE |
52 | * The licence and distribution terms for any publically available version or |
53 | * derivative of this code cannot be changed. i.e. this code cannot simply be | |
54 | * copied and put under another distribution licence | |
55 | * [including the GNU Public Licence.] | |
56 | */ | |
57 | ||
bbb8de09 | 58 | #include <assert.h> |
addb309a | 59 | #include <limits.h> |
b39fc560 | 60 | #include "internal/cryptlib.h" |
d02b48c6 | 61 | #include "bn_lcl.h" |
98186eb4 | 62 | #include <openssl/opensslconf.h> |
d02b48c6 | 63 | |
df11e1e9 | 64 | /* This stuff appears to be completely unused, so is deprecated */ |
98186eb4 | 65 | #if OPENSSL_API_COMPAT < 0x00908000L |
1d97c843 TH |
66 | /*- |
67 | * For a 32 bit machine | |
dfeab068 RE |
68 | * 2 - 4 == 128 |
69 | * 3 - 8 == 256 | |
70 | * 4 - 16 == 512 | |
71 | * 5 - 32 == 1024 | |
72 | * 6 - 64 == 2048 | |
73 | * 7 - 128 == 4096 | |
74 | * 8 - 256 == 8192 | |
75 | */ | |
0f113f3e MC |
76 | static int bn_limit_bits = 0; |
77 | static int bn_limit_num = 8; /* (1<<bn_limit_bits) */ | |
78 | static int bn_limit_bits_low = 0; | |
79 | static int bn_limit_num_low = 8; /* (1<<bn_limit_bits_low) */ | |
80 | static int bn_limit_bits_high = 0; | |
81 | static int bn_limit_num_high = 8; /* (1<<bn_limit_bits_high) */ | |
82 | static int bn_limit_bits_mont = 0; | |
83 | static int bn_limit_num_mont = 8; /* (1<<bn_limit_bits_mont) */ | |
dfeab068 | 84 | |
6b691a5c | 85 | void BN_set_params(int mult, int high, int low, int mont) |
0f113f3e MC |
86 | { |
87 | if (mult >= 0) { | |
88 | if (mult > (int)(sizeof(int) * 8) - 1) | |
89 | mult = sizeof(int) * 8 - 1; | |
90 | bn_limit_bits = mult; | |
91 | bn_limit_num = 1 << mult; | |
92 | } | |
93 | if (high >= 0) { | |
94 | if (high > (int)(sizeof(int) * 8) - 1) | |
95 | high = sizeof(int) * 8 - 1; | |
96 | bn_limit_bits_high = high; | |
97 | bn_limit_num_high = 1 << high; | |
98 | } | |
99 | if (low >= 0) { | |
100 | if (low > (int)(sizeof(int) * 8) - 1) | |
101 | low = sizeof(int) * 8 - 1; | |
102 | bn_limit_bits_low = low; | |
103 | bn_limit_num_low = 1 << low; | |
104 | } | |
105 | if (mont >= 0) { | |
106 | if (mont > (int)(sizeof(int) * 8) - 1) | |
107 | mont = sizeof(int) * 8 - 1; | |
108 | bn_limit_bits_mont = mont; | |
109 | bn_limit_num_mont = 1 << mont; | |
110 | } | |
111 | } | |
dfeab068 | 112 | |
6b691a5c | 113 | int BN_get_params(int which) |
0f113f3e MC |
114 | { |
115 | if (which == 0) | |
116 | return (bn_limit_bits); | |
117 | else if (which == 1) | |
118 | return (bn_limit_bits_high); | |
119 | else if (which == 2) | |
120 | return (bn_limit_bits_low); | |
121 | else if (which == 3) | |
122 | return (bn_limit_bits_mont); | |
123 | else | |
124 | return (0); | |
125 | } | |
df11e1e9 | 126 | #endif |
d02b48c6 | 127 | |
98499135 | 128 | const BIGNUM *BN_value_one(void) |
0f113f3e MC |
129 | { |
130 | static const BN_ULONG data_one = 1L; | |
131 | static const BIGNUM const_one = | |
132 | { (BN_ULONG *)&data_one, 1, 1, 0, BN_FLG_STATIC_DATA }; | |
d02b48c6 | 133 | |
0f113f3e MC |
134 | return (&const_one); |
135 | } | |
d02b48c6 | 136 | |
6b691a5c | 137 | int BN_num_bits_word(BN_ULONG l) |
0f113f3e MC |
138 | { |
139 | static const unsigned char bits[256] = { | |
140 | 0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, | |
141 | 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, | |
142 | 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, | |
143 | 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, | |
144 | 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, | |
145 | 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, | |
146 | 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, | |
147 | 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, | |
148 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
149 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
150 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
151 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
152 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
153 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
154 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
155 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
156 | }; | |
d02b48c6 | 157 | |
dfeab068 | 158 | #if defined(SIXTY_FOUR_BIT_LONG) |
0f113f3e MC |
159 | if (l & 0xffffffff00000000L) { |
160 | if (l & 0xffff000000000000L) { | |
161 | if (l & 0xff00000000000000L) { | |
162 | return (bits[(int)(l >> 56)] + 56); | |
163 | } else | |
164 | return (bits[(int)(l >> 48)] + 48); | |
165 | } else { | |
166 | if (l & 0x0000ff0000000000L) { | |
167 | return (bits[(int)(l >> 40)] + 40); | |
168 | } else | |
169 | return (bits[(int)(l >> 32)] + 32); | |
170 | } | |
171 | } else | |
d02b48c6 | 172 | #else |
0f113f3e MC |
173 | # ifdef SIXTY_FOUR_BIT |
174 | if (l & 0xffffffff00000000LL) { | |
175 | if (l & 0xffff000000000000LL) { | |
176 | if (l & 0xff00000000000000LL) { | |
177 | return (bits[(int)(l >> 56)] + 56); | |
178 | } else | |
179 | return (bits[(int)(l >> 48)] + 48); | |
180 | } else { | |
181 | if (l & 0x0000ff0000000000LL) { | |
182 | return (bits[(int)(l >> 40)] + 40); | |
183 | } else | |
184 | return (bits[(int)(l >> 32)] + 32); | |
185 | } | |
186 | } else | |
187 | # endif | |
d02b48c6 | 188 | #endif |
0f113f3e | 189 | { |
d02b48c6 | 190 | #if defined(THIRTY_TWO_BIT) || defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG) |
0f113f3e MC |
191 | if (l & 0xffff0000L) { |
192 | if (l & 0xff000000L) | |
193 | return (bits[(int)(l >> 24L)] + 24); | |
194 | else | |
195 | return (bits[(int)(l >> 16L)] + 16); | |
196 | } else | |
d02b48c6 | 197 | #endif |
0f113f3e | 198 | { |
4a47f556 | 199 | #if defined(THIRTY_TWO_BIT) || defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG) |
0f113f3e MC |
200 | if (l & 0xff00L) |
201 | return (bits[(int)(l >> 8)] + 8); | |
202 | else | |
d02b48c6 | 203 | #endif |
0f113f3e MC |
204 | return (bits[(int)(l)]); |
205 | } | |
206 | } | |
207 | } | |
d02b48c6 | 208 | |
84c15db5 | 209 | int BN_num_bits(const BIGNUM *a) |
0f113f3e MC |
210 | { |
211 | int i = a->top - 1; | |
212 | bn_check_top(a); | |
dfeab068 | 213 | |
0f113f3e MC |
214 | if (BN_is_zero(a)) |
215 | return 0; | |
216 | return ((i * BN_BITS2) + BN_num_bits_word(a->d[i])); | |
217 | } | |
d02b48c6 | 218 | |
9f040d6d RS |
219 | static void bn_free_d(BIGNUM *a) |
220 | { | |
221 | if (BN_get_flags(a,BN_FLG_SECURE)) | |
222 | OPENSSL_secure_free(a->d); | |
223 | else | |
224 | OPENSSL_free(a->d); | |
225 | } | |
226 | ||
227 | ||
6b691a5c | 228 | void BN_clear_free(BIGNUM *a) |
0f113f3e MC |
229 | { |
230 | int i; | |
231 | ||
232 | if (a == NULL) | |
233 | return; | |
234 | bn_check_top(a); | |
235 | if (a->d != NULL) { | |
236 | OPENSSL_cleanse(a->d, a->dmax * sizeof(a->d[0])); | |
9f040d6d RS |
237 | if (!BN_get_flags(a, BN_FLG_STATIC_DATA)) |
238 | bn_free_d(a); | |
0f113f3e MC |
239 | } |
240 | i = BN_get_flags(a, BN_FLG_MALLOCED); | |
9f040d6d | 241 | OPENSSL_cleanse(a, sizeof(*a)); |
0f113f3e MC |
242 | if (i) |
243 | OPENSSL_free(a); | |
244 | } | |
d02b48c6 | 245 | |
6b691a5c | 246 | void BN_free(BIGNUM *a) |
0f113f3e MC |
247 | { |
248 | if (a == NULL) | |
249 | return; | |
250 | bn_check_top(a); | |
b548a1f1 | 251 | if (!BN_get_flags(a, BN_FLG_STATIC_DATA)) |
9f040d6d | 252 | bn_free_d(a); |
0f113f3e MC |
253 | if (a->flags & BN_FLG_MALLOCED) |
254 | OPENSSL_free(a); | |
255 | else { | |
98186eb4 | 256 | #if OPENSSL_API_COMPAT < 0x00908000L |
0f113f3e | 257 | a->flags |= BN_FLG_FREE; |
2ae1ea37 | 258 | #endif |
0f113f3e MC |
259 | a->d = NULL; |
260 | } | |
261 | } | |
dfeab068 | 262 | |
d59c7c81 | 263 | void bn_init(BIGNUM *a) |
0f113f3e | 264 | { |
d59c7c81 RS |
265 | static BIGNUM nilbn; |
266 | ||
267 | *a = nilbn; | |
0f113f3e MC |
268 | bn_check_top(a); |
269 | } | |
d02b48c6 | 270 | |
6b691a5c | 271 | BIGNUM *BN_new(void) |
0f113f3e MC |
272 | { |
273 | BIGNUM *ret; | |
274 | ||
64b25758 | 275 | if ((ret = OPENSSL_zalloc(sizeof(*ret))) == NULL) { |
0f113f3e MC |
276 | BNerr(BN_F_BN_NEW, ERR_R_MALLOC_FAILURE); |
277 | return (NULL); | |
278 | } | |
279 | ret->flags = BN_FLG_MALLOCED; | |
0f113f3e MC |
280 | bn_check_top(ret); |
281 | return (ret); | |
282 | } | |
d02b48c6 | 283 | |
74924dcb RS |
284 | BIGNUM *BN_secure_new(void) |
285 | { | |
286 | BIGNUM *ret = BN_new(); | |
90945fa3 | 287 | if (ret != NULL) |
74924dcb RS |
288 | ret->flags |= BN_FLG_SECURE; |
289 | return (ret); | |
290 | } | |
291 | ||
8707e3be | 292 | /* This is used by bn_expand2() */ |
020fc820 | 293 | /* The caller MUST check that words > b->dmax before calling this */ |
6343829a | 294 | static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words) |
0f113f3e MC |
295 | { |
296 | BN_ULONG *A, *a = NULL; | |
297 | const BN_ULONG *B; | |
298 | int i; | |
299 | ||
300 | bn_check_top(b); | |
301 | ||
302 | if (words > (INT_MAX / (4 * BN_BITS2))) { | |
303 | BNerr(BN_F_BN_EXPAND_INTERNAL, BN_R_BIGNUM_TOO_LONG); | |
304 | return NULL; | |
305 | } | |
306 | if (BN_get_flags(b, BN_FLG_STATIC_DATA)) { | |
307 | BNerr(BN_F_BN_EXPAND_INTERNAL, BN_R_EXPAND_ON_STATIC_BIGNUM_DATA); | |
308 | return (NULL); | |
309 | } | |
74924dcb | 310 | if (BN_get_flags(b,BN_FLG_SECURE)) |
d8ca44ba | 311 | a = A = OPENSSL_secure_zalloc(words * sizeof(*a)); |
74924dcb | 312 | else |
d8ca44ba | 313 | a = A = OPENSSL_zalloc(words * sizeof(*a)); |
0f113f3e MC |
314 | if (A == NULL) { |
315 | BNerr(BN_F_BN_EXPAND_INTERNAL, ERR_R_MALLOC_FAILURE); | |
316 | return (NULL); | |
317 | } | |
f8571ce8 | 318 | |
dfeab068 | 319 | #if 1 |
0f113f3e MC |
320 | B = b->d; |
321 | /* Check if the previous number needs to be copied */ | |
322 | if (B != NULL) { | |
323 | for (i = b->top >> 2; i > 0; i--, A += 4, B += 4) { | |
324 | /* | |
325 | * The fact that the loop is unrolled | |
326 | * 4-wise is a tribute to Intel. It's | |
327 | * the one that doesn't have enough | |
0d4fb843 | 328 | * registers to accommodate more data. |
0f113f3e MC |
329 | * I'd unroll it 8-wise otherwise:-) |
330 | * | |
331 | * <appro@fy.chalmers.se> | |
332 | */ | |
333 | BN_ULONG a0, a1, a2, a3; | |
334 | a0 = B[0]; | |
335 | a1 = B[1]; | |
336 | a2 = B[2]; | |
337 | a3 = B[3]; | |
338 | A[0] = a0; | |
339 | A[1] = a1; | |
340 | A[2] = a2; | |
341 | A[3] = a3; | |
342 | } | |
0f113f3e MC |
343 | switch (b->top & 3) { |
344 | case 3: | |
345 | A[2] = B[2]; | |
346 | case 2: | |
347 | A[1] = B[1]; | |
348 | case 1: | |
349 | A[0] = B[0]; | |
350 | case 0: | |
23d38992 | 351 | /* Without the "case 0" some old optimizers got this wrong. */ |
0f113f3e MC |
352 | ; |
353 | } | |
354 | } | |
dfeab068 | 355 | #else |
16f8d4eb | 356 | memset(A, 0, sizeof(*A) * words); |
0f113f3e | 357 | memcpy(A, b->d, sizeof(b->d[0]) * b->top); |
dfeab068 | 358 | #endif |
dfeab068 | 359 | |
0f113f3e MC |
360 | return (a); |
361 | } | |
362 | ||
363 | /* | |
364 | * This is an internal function that should not be used in applications. It | |
365 | * ensures that 'b' has enough room for a 'words' word number and initialises | |
366 | * any unused part of b->d with leading zeros. It is mostly used by the | |
367 | * various BIGNUM routines. If there is an error, NULL is returned. If not, | |
368 | * 'b' is returned. | |
369 | */ | |
020fc820 | 370 | |
6343829a | 371 | BIGNUM *bn_expand2(BIGNUM *b, int words) |
0f113f3e MC |
372 | { |
373 | bn_check_top(b); | |
374 | ||
375 | if (words > b->dmax) { | |
376 | BN_ULONG *a = bn_expand_internal(b, words); | |
377 | if (!a) | |
378 | return NULL; | |
74924dcb | 379 | if (b->d) { |
9f040d6d RS |
380 | OPENSSL_cleanse(b->d, b->dmax * sizeof(b->d[0])); |
381 | bn_free_d(b); | |
74924dcb | 382 | } |
0f113f3e MC |
383 | b->d = a; |
384 | b->dmax = words; | |
385 | } | |
2bfd2c74 | 386 | |
0f113f3e MC |
387 | bn_check_top(b); |
388 | return b; | |
389 | } | |
d02b48c6 | 390 | |
84c15db5 | 391 | BIGNUM *BN_dup(const BIGNUM *a) |
0f113f3e MC |
392 | { |
393 | BIGNUM *t; | |
394 | ||
395 | if (a == NULL) | |
396 | return NULL; | |
397 | bn_check_top(a); | |
398 | ||
74924dcb | 399 | t = BN_get_flags(a, BN_FLG_SECURE) ? BN_secure_new() : BN_new(); |
0f113f3e MC |
400 | if (t == NULL) |
401 | return NULL; | |
402 | if (!BN_copy(t, a)) { | |
403 | BN_free(t); | |
404 | return NULL; | |
405 | } | |
406 | bn_check_top(t); | |
407 | return t; | |
408 | } | |
d02b48c6 | 409 | |
84c15db5 | 410 | BIGNUM *BN_copy(BIGNUM *a, const BIGNUM *b) |
0f113f3e MC |
411 | { |
412 | int i; | |
413 | BN_ULONG *A; | |
414 | const BN_ULONG *B; | |
58964a49 | 415 | |
0f113f3e | 416 | bn_check_top(b); |
dfeab068 | 417 | |
0f113f3e MC |
418 | if (a == b) |
419 | return (a); | |
420 | if (bn_wexpand(a, b->top) == NULL) | |
421 | return (NULL); | |
58964a49 RE |
422 | |
423 | #if 1 | |
0f113f3e MC |
424 | A = a->d; |
425 | B = b->d; | |
426 | for (i = b->top >> 2; i > 0; i--, A += 4, B += 4) { | |
427 | BN_ULONG a0, a1, a2, a3; | |
428 | a0 = B[0]; | |
429 | a1 = B[1]; | |
430 | a2 = B[2]; | |
431 | a3 = B[3]; | |
432 | A[0] = a0; | |
433 | A[1] = a1; | |
434 | A[2] = a2; | |
435 | A[3] = a3; | |
436 | } | |
437 | /* ultrix cc workaround, see comments in bn_expand_internal */ | |
438 | switch (b->top & 3) { | |
439 | case 3: | |
440 | A[2] = B[2]; | |
441 | case 2: | |
442 | A[1] = B[1]; | |
443 | case 1: | |
444 | A[0] = B[0]; | |
445 | case 0:; | |
446 | } | |
58964a49 | 447 | #else |
0f113f3e | 448 | memcpy(a->d, b->d, sizeof(b->d[0]) * b->top); |
58964a49 RE |
449 | #endif |
450 | ||
0f113f3e MC |
451 | a->top = b->top; |
452 | a->neg = b->neg; | |
453 | bn_check_top(a); | |
454 | return (a); | |
455 | } | |
d02b48c6 | 456 | |
78a0c1f1 | 457 | void BN_swap(BIGNUM *a, BIGNUM *b) |
0f113f3e MC |
458 | { |
459 | int flags_old_a, flags_old_b; | |
460 | BN_ULONG *tmp_d; | |
461 | int tmp_top, tmp_dmax, tmp_neg; | |
462 | ||
463 | bn_check_top(a); | |
464 | bn_check_top(b); | |
465 | ||
466 | flags_old_a = a->flags; | |
467 | flags_old_b = b->flags; | |
468 | ||
469 | tmp_d = a->d; | |
470 | tmp_top = a->top; | |
471 | tmp_dmax = a->dmax; | |
472 | tmp_neg = a->neg; | |
473 | ||
474 | a->d = b->d; | |
475 | a->top = b->top; | |
476 | a->dmax = b->dmax; | |
477 | a->neg = b->neg; | |
478 | ||
479 | b->d = tmp_d; | |
480 | b->top = tmp_top; | |
481 | b->dmax = tmp_dmax; | |
482 | b->neg = tmp_neg; | |
483 | ||
484 | a->flags = | |
485 | (flags_old_a & BN_FLG_MALLOCED) | (flags_old_b & BN_FLG_STATIC_DATA); | |
486 | b->flags = | |
487 | (flags_old_b & BN_FLG_MALLOCED) | (flags_old_a & BN_FLG_STATIC_DATA); | |
488 | bn_check_top(a); | |
489 | bn_check_top(b); | |
490 | } | |
78a0c1f1 | 491 | |
6b691a5c | 492 | void BN_clear(BIGNUM *a) |
0f113f3e MC |
493 | { |
494 | bn_check_top(a); | |
495 | if (a->d != NULL) | |
16f8d4eb | 496 | memset(a->d, 0, sizeof(*a->d) * a->dmax); |
0f113f3e MC |
497 | a->top = 0; |
498 | a->neg = 0; | |
499 | } | |
d02b48c6 | 500 | |
020fc820 | 501 | BN_ULONG BN_get_word(const BIGNUM *a) |
0f113f3e MC |
502 | { |
503 | if (a->top > 1) | |
504 | return BN_MASK2; | |
505 | else if (a->top == 1) | |
506 | return a->d[0]; | |
507 | /* a->top == 0 */ | |
508 | return 0; | |
509 | } | |
d02b48c6 | 510 | |
e042540f | 511 | int BN_set_word(BIGNUM *a, BN_ULONG w) |
0f113f3e MC |
512 | { |
513 | bn_check_top(a); | |
514 | if (bn_expand(a, (int)sizeof(BN_ULONG) * 8) == NULL) | |
515 | return (0); | |
516 | a->neg = 0; | |
517 | a->d[0] = w; | |
518 | a->top = (w ? 1 : 0); | |
519 | bn_check_top(a); | |
520 | return (1); | |
521 | } | |
d02b48c6 | 522 | |
6343829a | 523 | BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret) |
0f113f3e MC |
524 | { |
525 | unsigned int i, m; | |
526 | unsigned int n; | |
527 | BN_ULONG l; | |
528 | BIGNUM *bn = NULL; | |
529 | ||
530 | if (ret == NULL) | |
531 | ret = bn = BN_new(); | |
532 | if (ret == NULL) | |
533 | return (NULL); | |
534 | bn_check_top(ret); | |
22dc08d0 | 535 | /* Skip leading zero's. */ |
3c65047d | 536 | for ( ; len > 0 && *s == 0; s++, len--) |
22dc08d0 | 537 | continue; |
0f113f3e MC |
538 | n = len; |
539 | if (n == 0) { | |
540 | ret->top = 0; | |
541 | return (ret); | |
542 | } | |
543 | i = ((n - 1) / BN_BYTES) + 1; | |
544 | m = ((n - 1) % (BN_BYTES)); | |
545 | if (bn_wexpand(ret, (int)i) == NULL) { | |
23a1d5e9 | 546 | BN_free(bn); |
0f113f3e MC |
547 | return NULL; |
548 | } | |
549 | ret->top = i; | |
550 | ret->neg = 0; | |
22dc08d0 | 551 | l = 0; |
0f113f3e MC |
552 | while (n--) { |
553 | l = (l << 8L) | *(s++); | |
554 | if (m-- == 0) { | |
555 | ret->d[--i] = l; | |
556 | l = 0; | |
557 | m = BN_BYTES - 1; | |
558 | } | |
559 | } | |
560 | /* | |
561 | * need to call this due to clear byte at top if avoiding having the top | |
562 | * bit set (-ve number) | |
563 | */ | |
564 | bn_correct_top(ret); | |
565 | return (ret); | |
566 | } | |
d02b48c6 RE |
567 | |
568 | /* ignore negative */ | |
85a4807f | 569 | static int bn2binpad(const BIGNUM *a, unsigned char *to, int tolen) |
0f113f3e | 570 | { |
85a4807f | 571 | int i; |
0f113f3e MC |
572 | BN_ULONG l; |
573 | ||
574 | bn_check_top(a); | |
85a4807f DSH |
575 | i = BN_num_bytes(a); |
576 | if (tolen == -1) | |
577 | tolen = i; | |
578 | else if (tolen < i) | |
579 | return -1; | |
580 | /* Add leading zeroes if necessary */ | |
581 | if (tolen > i) { | |
582 | memset(to, 0, tolen - i); | |
583 | to += tolen - i; | |
584 | } | |
0f113f3e MC |
585 | while (i--) { |
586 | l = a->d[i / BN_BYTES]; | |
587 | *(to++) = (unsigned char)(l >> (8 * (i % BN_BYTES))) & 0xff; | |
588 | } | |
85a4807f DSH |
589 | return tolen; |
590 | } | |
591 | ||
592 | int BN_bn2binpad(const BIGNUM *a, unsigned char *to, int tolen) | |
593 | { | |
594 | if (tolen < 0) | |
595 | return -1; | |
596 | return bn2binpad(a, to, tolen); | |
597 | } | |
598 | ||
599 | int BN_bn2bin(const BIGNUM *a, unsigned char *to) | |
600 | { | |
601 | return bn2binpad(a, to, -1); | |
602 | } | |
603 | ||
604 | BIGNUM *BN_lebin2bn(const unsigned char *s, int len, BIGNUM *ret) | |
605 | { | |
606 | unsigned int i, m; | |
607 | unsigned int n; | |
608 | BN_ULONG l; | |
609 | BIGNUM *bn = NULL; | |
610 | ||
611 | if (ret == NULL) | |
612 | ret = bn = BN_new(); | |
613 | if (ret == NULL) | |
614 | return (NULL); | |
615 | bn_check_top(ret); | |
616 | s += len - 1; | |
617 | /* Skip trailing zeroes. */ | |
618 | for ( ; len > 0 && *s == 0; s--, len--) | |
619 | continue; | |
620 | n = len; | |
621 | if (n == 0) { | |
622 | ret->top = 0; | |
623 | return ret; | |
624 | } | |
625 | i = ((n - 1) / BN_BYTES) + 1; | |
626 | m = ((n - 1) % (BN_BYTES)); | |
627 | if (bn_wexpand(ret, (int)i) == NULL) { | |
628 | BN_free(bn); | |
629 | return NULL; | |
630 | } | |
631 | ret->top = i; | |
632 | ret->neg = 0; | |
633 | l = 0; | |
634 | while (n--) { | |
635 | l = (l << 8L) | *(s--); | |
636 | if (m-- == 0) { | |
637 | ret->d[--i] = l; | |
638 | l = 0; | |
639 | m = BN_BYTES - 1; | |
640 | } | |
641 | } | |
642 | /* | |
643 | * need to call this due to clear byte at top if avoiding having the top | |
644 | * bit set (-ve number) | |
645 | */ | |
646 | bn_correct_top(ret); | |
647 | return ret; | |
648 | } | |
649 | ||
650 | int BN_bn2lebinpad(const BIGNUM *a, unsigned char *to, int tolen) | |
651 | { | |
652 | int i; | |
653 | BN_ULONG l; | |
654 | bn_check_top(a); | |
655 | i = BN_num_bytes(a); | |
656 | if (tolen < i) | |
657 | return -1; | |
658 | /* Add trailing zeroes if necessary */ | |
659 | if (tolen > i) | |
660 | memset(to + i, 0, tolen - i); | |
661 | to += i - 1; | |
662 | while (i--) { | |
663 | l = a->d[i / BN_BYTES]; | |
664 | *(to--) = (unsigned char)(l >> (8 * (i % BN_BYTES))) & 0xff; | |
665 | } | |
666 | return tolen; | |
0f113f3e | 667 | } |
d02b48c6 | 668 | |
84c15db5 | 669 | int BN_ucmp(const BIGNUM *a, const BIGNUM *b) |
0f113f3e MC |
670 | { |
671 | int i; | |
672 | BN_ULONG t1, t2, *ap, *bp; | |
673 | ||
674 | bn_check_top(a); | |
675 | bn_check_top(b); | |
676 | ||
677 | i = a->top - b->top; | |
678 | if (i != 0) | |
679 | return (i); | |
680 | ap = a->d; | |
681 | bp = b->d; | |
682 | for (i = a->top - 1; i >= 0; i--) { | |
683 | t1 = ap[i]; | |
684 | t2 = bp[i]; | |
685 | if (t1 != t2) | |
686 | return ((t1 > t2) ? 1 : -1); | |
687 | } | |
688 | return (0); | |
689 | } | |
d02b48c6 | 690 | |
84c15db5 | 691 | int BN_cmp(const BIGNUM *a, const BIGNUM *b) |
0f113f3e MC |
692 | { |
693 | int i; | |
694 | int gt, lt; | |
695 | BN_ULONG t1, t2; | |
696 | ||
697 | if ((a == NULL) || (b == NULL)) { | |
698 | if (a != NULL) | |
699 | return (-1); | |
700 | else if (b != NULL) | |
701 | return (1); | |
702 | else | |
703 | return (0); | |
704 | } | |
705 | ||
706 | bn_check_top(a); | |
707 | bn_check_top(b); | |
708 | ||
709 | if (a->neg != b->neg) { | |
710 | if (a->neg) | |
711 | return (-1); | |
712 | else | |
713 | return (1); | |
714 | } | |
715 | if (a->neg == 0) { | |
716 | gt = 1; | |
717 | lt = -1; | |
718 | } else { | |
719 | gt = -1; | |
720 | lt = 1; | |
721 | } | |
722 | ||
723 | if (a->top > b->top) | |
724 | return (gt); | |
725 | if (a->top < b->top) | |
726 | return (lt); | |
727 | for (i = a->top - 1; i >= 0; i--) { | |
728 | t1 = a->d[i]; | |
729 | t2 = b->d[i]; | |
730 | if (t1 > t2) | |
731 | return (gt); | |
732 | if (t1 < t2) | |
733 | return (lt); | |
734 | } | |
735 | return (0); | |
736 | } | |
d02b48c6 | 737 | |
6b691a5c | 738 | int BN_set_bit(BIGNUM *a, int n) |
0f113f3e MC |
739 | { |
740 | int i, j, k; | |
741 | ||
742 | if (n < 0) | |
743 | return 0; | |
744 | ||
745 | i = n / BN_BITS2; | |
746 | j = n % BN_BITS2; | |
747 | if (a->top <= i) { | |
748 | if (bn_wexpand(a, i + 1) == NULL) | |
749 | return (0); | |
750 | for (k = a->top; k < i + 1; k++) | |
751 | a->d[k] = 0; | |
752 | a->top = i + 1; | |
753 | } | |
754 | ||
755 | a->d[i] |= (((BN_ULONG)1) << j); | |
756 | bn_check_top(a); | |
757 | return (1); | |
758 | } | |
d02b48c6 | 759 | |
6b691a5c | 760 | int BN_clear_bit(BIGNUM *a, int n) |
0f113f3e MC |
761 | { |
762 | int i, j; | |
d02b48c6 | 763 | |
0f113f3e MC |
764 | bn_check_top(a); |
765 | if (n < 0) | |
766 | return 0; | |
1a017330 | 767 | |
0f113f3e MC |
768 | i = n / BN_BITS2; |
769 | j = n % BN_BITS2; | |
770 | if (a->top <= i) | |
771 | return (0); | |
d02b48c6 | 772 | |
0f113f3e MC |
773 | a->d[i] &= (~(((BN_ULONG)1) << j)); |
774 | bn_correct_top(a); | |
775 | return (1); | |
776 | } | |
d02b48c6 | 777 | |
84c15db5 | 778 | int BN_is_bit_set(const BIGNUM *a, int n) |
0f113f3e MC |
779 | { |
780 | int i, j; | |
781 | ||
782 | bn_check_top(a); | |
783 | if (n < 0) | |
784 | return 0; | |
785 | i = n / BN_BITS2; | |
786 | j = n % BN_BITS2; | |
787 | if (a->top <= i) | |
788 | return 0; | |
789 | return (int)(((a->d[i]) >> j) & ((BN_ULONG)1)); | |
790 | } | |
d02b48c6 | 791 | |
6b691a5c | 792 | int BN_mask_bits(BIGNUM *a, int n) |
0f113f3e MC |
793 | { |
794 | int b, w; | |
795 | ||
796 | bn_check_top(a); | |
797 | if (n < 0) | |
798 | return 0; | |
799 | ||
800 | w = n / BN_BITS2; | |
801 | b = n % BN_BITS2; | |
802 | if (w >= a->top) | |
803 | return 0; | |
804 | if (b == 0) | |
805 | a->top = w; | |
806 | else { | |
807 | a->top = w + 1; | |
808 | a->d[w] &= ~(BN_MASK2 << b); | |
809 | } | |
810 | bn_correct_top(a); | |
811 | return (1); | |
812 | } | |
dfeab068 | 813 | |
ff22e913 | 814 | void BN_set_negative(BIGNUM *a, int b) |
0f113f3e MC |
815 | { |
816 | if (b && !BN_is_zero(a)) | |
817 | a->neg = 1; | |
818 | else | |
819 | a->neg = 0; | |
820 | } | |
ff22e913 | 821 | |
cbd48ba6 | 822 | int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n) |
0f113f3e MC |
823 | { |
824 | int i; | |
825 | BN_ULONG aa, bb; | |
826 | ||
827 | aa = a[n - 1]; | |
828 | bb = b[n - 1]; | |
829 | if (aa != bb) | |
830 | return ((aa > bb) ? 1 : -1); | |
831 | for (i = n - 2; i >= 0; i--) { | |
832 | aa = a[i]; | |
833 | bb = b[i]; | |
834 | if (aa != bb) | |
835 | return ((aa > bb) ? 1 : -1); | |
836 | } | |
837 | return (0); | |
838 | } | |
839 | ||
840 | /* | |
841 | * Here follows a specialised variants of bn_cmp_words(). It has the | |
399de496 | 842 | * capability of performing the operation on arrays of different sizes. The |
0f113f3e | 843 | * sizes of those arrays is expressed through cl, which is the common length |
399de496 | 844 | * ( basically, min(len(a),len(b)) ), and dl, which is the delta between the |
0f113f3e MC |
845 | * two lengths, calculated as len(a)-len(b). All lengths are the number of |
846 | * BN_ULONGs... | |
847 | */ | |
848 | ||
849 | int bn_cmp_part_words(const BN_ULONG *a, const BN_ULONG *b, int cl, int dl) | |
850 | { | |
851 | int n, i; | |
852 | n = cl - 1; | |
853 | ||
854 | if (dl < 0) { | |
855 | for (i = dl; i < 0; i++) { | |
856 | if (b[n - i] != 0) | |
857 | return -1; /* a < b */ | |
858 | } | |
859 | } | |
860 | if (dl > 0) { | |
861 | for (i = dl; i > 0; i--) { | |
862 | if (a[n + i] != 0) | |
863 | return 1; /* a > b */ | |
864 | } | |
865 | } | |
866 | return bn_cmp_words(a, b, cl); | |
867 | } | |
868 | ||
869 | /* | |
870 | * Constant-time conditional swap of a and b. | |
f9b6c0ba DSH |
871 | * a and b are swapped if condition is not 0. The code assumes that at most one bit of condition is set. |
872 | * nwords is the number of words to swap. The code assumes that at least nwords are allocated in both a and b, | |
873 | * and that no more than nwords are used by either a or b. | |
874 | * a and b cannot be the same number | |
875 | */ | |
876 | void BN_consttime_swap(BN_ULONG condition, BIGNUM *a, BIGNUM *b, int nwords) | |
0f113f3e MC |
877 | { |
878 | BN_ULONG t; | |
879 | int i; | |
f9b6c0ba | 880 | |
0f113f3e MC |
881 | bn_wcheck_size(a, nwords); |
882 | bn_wcheck_size(b, nwords); | |
f9b6c0ba | 883 | |
0f113f3e MC |
884 | assert(a != b); |
885 | assert((condition & (condition - 1)) == 0); | |
886 | assert(sizeof(BN_ULONG) >= sizeof(int)); | |
f9b6c0ba | 887 | |
0f113f3e | 888 | condition = ((condition - 1) >> (BN_BITS2 - 1)) - 1; |
f9b6c0ba | 889 | |
0f113f3e MC |
890 | t = (a->top ^ b->top) & condition; |
891 | a->top ^= t; | |
892 | b->top ^= t; | |
f9b6c0ba DSH |
893 | |
894 | #define BN_CONSTTIME_SWAP(ind) \ | |
0f113f3e MC |
895 | do { \ |
896 | t = (a->d[ind] ^ b->d[ind]) & condition; \ | |
897 | a->d[ind] ^= t; \ | |
898 | b->d[ind] ^= t; \ | |
899 | } while (0) | |
900 | ||
901 | switch (nwords) { | |
902 | default: | |
903 | for (i = 10; i < nwords; i++) | |
904 | BN_CONSTTIME_SWAP(i); | |
905 | /* Fallthrough */ | |
906 | case 10: | |
907 | BN_CONSTTIME_SWAP(9); /* Fallthrough */ | |
908 | case 9: | |
909 | BN_CONSTTIME_SWAP(8); /* Fallthrough */ | |
910 | case 8: | |
911 | BN_CONSTTIME_SWAP(7); /* Fallthrough */ | |
912 | case 7: | |
913 | BN_CONSTTIME_SWAP(6); /* Fallthrough */ | |
914 | case 6: | |
915 | BN_CONSTTIME_SWAP(5); /* Fallthrough */ | |
916 | case 5: | |
917 | BN_CONSTTIME_SWAP(4); /* Fallthrough */ | |
918 | case 4: | |
919 | BN_CONSTTIME_SWAP(3); /* Fallthrough */ | |
920 | case 3: | |
921 | BN_CONSTTIME_SWAP(2); /* Fallthrough */ | |
922 | case 2: | |
923 | BN_CONSTTIME_SWAP(1); /* Fallthrough */ | |
924 | case 1: | |
925 | BN_CONSTTIME_SWAP(0); | |
926 | } | |
f9b6c0ba DSH |
927 | #undef BN_CONSTTIME_SWAP |
928 | } | |
2514fa79 DSH |
929 | |
930 | /* Bits of security, see SP800-57 */ | |
931 | ||
932 | int BN_security_bits(int L, int N) | |
0f113f3e MC |
933 | { |
934 | int secbits, bits; | |
935 | if (L >= 15360) | |
936 | secbits = 256; | |
937 | else if (L >= 7690) | |
938 | secbits = 192; | |
939 | else if (L >= 3072) | |
940 | secbits = 128; | |
941 | else if (L >= 2048) | |
942 | secbits = 112; | |
943 | else if (L >= 1024) | |
944 | secbits = 80; | |
945 | else | |
946 | return 0; | |
947 | if (N == -1) | |
948 | return secbits; | |
949 | bits = N / 2; | |
950 | if (bits < 80) | |
951 | return 0; | |
952 | return bits >= secbits ? secbits : bits; | |
953 | } | |
85bcf27c MC |
954 | |
955 | void BN_zero_ex(BIGNUM *a) | |
0f113f3e MC |
956 | { |
957 | a->top = 0; | |
958 | a->neg = 0; | |
959 | } | |
85bcf27c MC |
960 | |
961 | int BN_abs_is_word(const BIGNUM *a, const BN_ULONG w) | |
0f113f3e MC |
962 | { |
963 | return ((a->top == 1) && (a->d[0] == w)) || ((w == 0) && (a->top == 0)); | |
964 | } | |
85bcf27c MC |
965 | |
966 | int BN_is_zero(const BIGNUM *a) | |
0f113f3e MC |
967 | { |
968 | return a->top == 0; | |
969 | } | |
85bcf27c MC |
970 | |
971 | int BN_is_one(const BIGNUM *a) | |
0f113f3e MC |
972 | { |
973 | return BN_abs_is_word(a, 1) && !a->neg; | |
974 | } | |
85bcf27c MC |
975 | |
976 | int BN_is_word(const BIGNUM *a, const BN_ULONG w) | |
0f113f3e MC |
977 | { |
978 | return BN_abs_is_word(a, w) && (!w || !a->neg); | |
979 | } | |
85bcf27c MC |
980 | |
981 | int BN_is_odd(const BIGNUM *a) | |
0f113f3e MC |
982 | { |
983 | return (a->top > 0) && (a->d[0] & 1); | |
984 | } | |
85bcf27c MC |
985 | |
986 | int BN_is_negative(const BIGNUM *a) | |
0f113f3e MC |
987 | { |
988 | return (a->neg != 0); | |
989 | } | |
85bcf27c | 990 | |
0f113f3e MC |
991 | int BN_to_montgomery(BIGNUM *r, const BIGNUM *a, BN_MONT_CTX *mont, |
992 | BN_CTX *ctx) | |
993 | { | |
994 | return BN_mod_mul_montgomery(r, a, &(mont->RR), mont, ctx); | |
995 | } | |
85bcf27c | 996 | |
fd7d2520 | 997 | void BN_with_flags(BIGNUM *dest, const BIGNUM *b, int flags) |
0f113f3e MC |
998 | { |
999 | dest->d = b->d; | |
1000 | dest->top = b->top; | |
1001 | dest->dmax = b->dmax; | |
1002 | dest->neg = b->neg; | |
1003 | dest->flags = ((dest->flags & BN_FLG_MALLOCED) | |
1004 | | (b->flags & ~BN_FLG_MALLOCED) | |
fd7d2520 | 1005 | | BN_FLG_STATIC_DATA | flags); |
0f113f3e | 1006 | } |
85bcf27c MC |
1007 | |
1008 | BN_GENCB *BN_GENCB_new(void) | |
0f113f3e MC |
1009 | { |
1010 | BN_GENCB *ret; | |
85bcf27c | 1011 | |
b4faea50 | 1012 | if ((ret = OPENSSL_malloc(sizeof(*ret))) == NULL) { |
0f113f3e MC |
1013 | BNerr(BN_F_BN_GENCB_NEW, ERR_R_MALLOC_FAILURE); |
1014 | return (NULL); | |
1015 | } | |
85bcf27c | 1016 | |
0f113f3e MC |
1017 | return ret; |
1018 | } | |
85bcf27c MC |
1019 | |
1020 | void BN_GENCB_free(BN_GENCB *cb) | |
0f113f3e MC |
1021 | { |
1022 | if (cb == NULL) | |
1023 | return; | |
1024 | OPENSSL_free(cb); | |
1025 | } | |
85bcf27c MC |
1026 | |
1027 | void BN_set_flags(BIGNUM *b, int n) | |
0f113f3e MC |
1028 | { |
1029 | b->flags |= n; | |
1030 | } | |
85bcf27c MC |
1031 | |
1032 | int BN_get_flags(const BIGNUM *b, int n) | |
0f113f3e MC |
1033 | { |
1034 | return b->flags & n; | |
1035 | } | |
85bcf27c MC |
1036 | |
1037 | /* Populate a BN_GENCB structure with an "old"-style callback */ | |
0f113f3e MC |
1038 | void BN_GENCB_set_old(BN_GENCB *gencb, void (*callback) (int, int, void *), |
1039 | void *cb_arg) | |
1040 | { | |
1041 | BN_GENCB *tmp_gencb = gencb; | |
1042 | tmp_gencb->ver = 1; | |
1043 | tmp_gencb->arg = cb_arg; | |
1044 | tmp_gencb->cb.cb_1 = callback; | |
1045 | } | |
85bcf27c MC |
1046 | |
1047 | /* Populate a BN_GENCB structure with a "new"-style callback */ | |
0f113f3e MC |
1048 | void BN_GENCB_set(BN_GENCB *gencb, int (*callback) (int, int, BN_GENCB *), |
1049 | void *cb_arg) | |
1050 | { | |
1051 | BN_GENCB *tmp_gencb = gencb; | |
1052 | tmp_gencb->ver = 2; | |
1053 | tmp_gencb->arg = cb_arg; | |
1054 | tmp_gencb->cb.cb_2 = callback; | |
1055 | } | |
85bcf27c MC |
1056 | |
1057 | void *BN_GENCB_get_arg(BN_GENCB *cb) | |
0f113f3e MC |
1058 | { |
1059 | return cb->arg; | |
1060 | } | |
85bcf27c MC |
1061 | |
1062 | BIGNUM *bn_wexpand(BIGNUM *a, int words) | |
0f113f3e MC |
1063 | { |
1064 | return (words <= a->dmax) ? a : bn_expand2(a, words); | |
1065 | } | |
85bcf27c MC |
1066 | |
1067 | void bn_correct_top(BIGNUM *a) | |
0f113f3e MC |
1068 | { |
1069 | BN_ULONG *ftl; | |
1070 | int tmp_top = a->top; | |
1071 | ||
1072 | if (tmp_top > 0) { | |
1073 | for (ftl = &(a->d[tmp_top - 1]); tmp_top > 0; tmp_top--) | |
1074 | if (*(ftl--)) | |
1075 | break; | |
1076 | a->top = tmp_top; | |
1077 | } | |
1078 | bn_pollute(a); | |
1079 | } |