1 /* crypto/bn/bn_nist.c */
2 /*
3 * Written by Nils Larsch for the OpenSSL project
4 */
5 /* ====================================================================
6 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in
17 * the documentation and/or other materials provided with the
18 * distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 * software must display the following acknowledgment:
22 * "This product includes software developed by the OpenSSL Project
23 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 * endorse or promote products derived from this software without
27 * prior written permission. For written permission, please contact
28 * openssl-core@openssl.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 * nor may "OpenSSL" appear in their names without prior written
32 * permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 * acknowledgment:
36 * "This product includes software developed by the OpenSSL Project
37 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com). This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58
59 #include "bn_lcl.h"
60 #include "cryptlib.h"
61
62 #define BN_NIST_192_TOP (192+BN_BITS2-1)/BN_BITS2
63 #define BN_NIST_224_TOP (224+BN_BITS2-1)/BN_BITS2
64 #define BN_NIST_256_TOP (256+BN_BITS2-1)/BN_BITS2
65 #define BN_NIST_384_TOP (384+BN_BITS2-1)/BN_BITS2
66 #define BN_NIST_521_TOP (521+BN_BITS2-1)/BN_BITS2
67
68 #if BN_BITS2 == 64
69 static const BN_ULONG _nist_p_192[] =
70 {0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFEULL,
71 0xFFFFFFFFFFFFFFFFULL};
72 static const BN_ULONG _nist_p_224[] =
73 {0x0000000000000001ULL,0xFFFFFFFF00000000ULL,
74 0xFFFFFFFFFFFFFFFFULL,0x00000000FFFFFFFFULL};
75 static const BN_ULONG _nist_p_256[] =
76 {0xFFFFFFFFFFFFFFFFULL,0x00000000FFFFFFFFULL,
77 0x0000000000000000ULL,0xFFFFFFFF00000001ULL};
78 static const BN_ULONG _nist_p_384[] =
79 {0x00000000FFFFFFFFULL,0xFFFFFFFF00000000ULL,
80 0xFFFFFFFFFFFFFFFEULL,0xFFFFFFFFFFFFFFFFULL,
81 0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL};
82 static const BN_ULONG _nist_p_521[] =
83 {0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,
84 0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,
85 0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,
86 0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,
87 0x00000000000001FFULL};
88 #elif BN_BITS2 == 32
89 static const BN_ULONG _nist_p_192[] = {0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFE,
90 0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF};
91 static const BN_ULONG _nist_p_224[] = {0x00000001,0x00000000,0x00000000,
92 0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF};
93 static const BN_ULONG _nist_p_256[] = {0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
94 0x00000000,0x00000000,0x00000000,0x00000001,0xFFFFFFFF};
95 static const BN_ULONG _nist_p_384[] = {0xFFFFFFFF,0x00000000,0x00000000,
96 0xFFFFFFFF,0xFFFFFFFE,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
97 0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF};
98 static const BN_ULONG _nist_p_521[] = {0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
99 0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
100 0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
101 0xFFFFFFFF,0x000001FF};
102 #elif BN_BITS2 == 16
103 static const BN_ULONG _nist_p_192[] = {0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFE,
104 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF};
105 static const BN_ULONG _nist_p_224[] = {0x0001,0x0000,0x0000,0x0000,0x0000,
106 0x0000,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF};
107 static const BN_ULONG _nist_p_256[] = {0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,
108 0xFFFF,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0001,0x0000,0xFFFF,
109 0xFFFF};
110 static const BN_ULONG _nist_p_384[] = {0xFFFF,0xFFFF,0x0000,0x0000,0x0000,
111 0x0000,0xFFFF,0xFFFF,0xFFFE,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,
112 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF};
113 static const BN_ULONG _nist_p_521[] = {0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,
114 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,
115 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,
116 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0x01FF};
117 #elif BN_BITS2 == 8
118 static const BN_ULONG _nist_p_192[] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
119 0xFE,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
120 0xFF,0xFF};
121 static const BN_ULONG _nist_p_224[] = {0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
122 0x00,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
123 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF};
124 static const BN_ULONG _nist_p_256[] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
125 0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
126 0x00,0x00,0x01,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF};
127 static const BN_ULONG _nist_p_384[] = {0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,
128 0x00,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF,0xFE,0xFF,0xFF,0xFF,0xFF,0xFF,
129 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
130 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF};
131 static const BN_ULONG _nist_p_521[] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
132 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
133 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
134 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
135 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
136 0xFF,0x01};
137 #endif
138
BN_get0_nist_prime_192(void)139 const BIGNUM *BN_get0_nist_prime_192(void)
140 {
141 static BIGNUM const_nist_192 = { (BN_ULONG *)_nist_p_192,
142 BN_NIST_192_TOP, BN_NIST_192_TOP, 0, BN_FLG_STATIC_DATA };
143 return &const_nist_192;
144 }
145
BN_get0_nist_prime_224(void)146 const BIGNUM *BN_get0_nist_prime_224(void)
147 {
148 static BIGNUM const_nist_224 = { (BN_ULONG *)_nist_p_224,
149 BN_NIST_224_TOP, BN_NIST_224_TOP, 0, BN_FLG_STATIC_DATA };
150 return &const_nist_224;
151 }
152
BN_get0_nist_prime_256(void)153 const BIGNUM *BN_get0_nist_prime_256(void)
154 {
155 static BIGNUM const_nist_256 = { (BN_ULONG *)_nist_p_256,
156 BN_NIST_256_TOP, BN_NIST_256_TOP, 0, BN_FLG_STATIC_DATA };
157 return &const_nist_256;
158 }
159
BN_get0_nist_prime_384(void)160 const BIGNUM *BN_get0_nist_prime_384(void)
161 {
162 static BIGNUM const_nist_384 = { (BN_ULONG *)_nist_p_384,
163 BN_NIST_384_TOP, BN_NIST_384_TOP, 0, BN_FLG_STATIC_DATA };
164 return &const_nist_384;
165 }
166
BN_get0_nist_prime_521(void)167 const BIGNUM *BN_get0_nist_prime_521(void)
168 {
169 static BIGNUM const_nist_521 = { (BN_ULONG *)_nist_p_521,
170 BN_NIST_521_TOP, BN_NIST_521_TOP, 0, BN_FLG_STATIC_DATA };
171 return &const_nist_521;
172 }
173
174 /* some misc internal functions */
175 #if BN_BITS2 != 64
176 static BN_ULONG _256_data[BN_NIST_256_TOP*6];
177 static int _is_set_256_data = 0;
178 static void _init_256_data(void);
179
180 static BN_ULONG _384_data[BN_NIST_384_TOP*8];
181 static int _is_set_384_data = 0;
182 static void _init_384_data(void);
183 #endif
184
185 #define BN_NIST_ADD_ONE(a) while (!(++(*(a)))) ++(a);
186
nist_cp_bn_0(BN_ULONG * buf,BN_ULONG * a,int top,int max)187 static void nist_cp_bn_0(BN_ULONG *buf, BN_ULONG *a, int top, int max)
188 {
189 int i;
190 BN_ULONG *_tmp1 = (buf), *_tmp2 = (a);
191 for (i = (top); i != 0; i--)
192 *_tmp1++ = *_tmp2++;
193 for (i = (max) - (top); i != 0; i--)
194 *_tmp1++ = (BN_ULONG) 0;
195 }
196
nist_cp_bn(BN_ULONG * buf,BN_ULONG * a,int top)197 static void nist_cp_bn(BN_ULONG *buf, BN_ULONG *a, int top)
198 {
199 int i;
200 BN_ULONG *_tmp1 = (buf), *_tmp2 = (a);
201 for (i = (top); i != 0; i--)
202 *_tmp1++ = *_tmp2++;
203 }
204
205 #if BN_BITS2 == 64
206 #define bn_cp_64(to, n, from, m) (to)[n] = (from)[m];
207 #define bn_64_set_0(to, n) (to)[n] = (BN_ULONG)0;
208 /* TBD */
209 #define bn_cp_32(to, n, from, m) (to)[n] = (from)[m];
210 #define bn_32_set_0(to, n) (to)[n] = (BN_ULONG)0;
211 #else
212 #define bn_cp_64(to, n, from, m) \
213 { \
214 bn_cp_32(to, (n)*2, from, (m)*2); \
215 bn_cp_32(to, (n)*2+1, from, (m)*2+1); \
216 }
217 #define bn_64_set_0(to, n) \
218 { \
219 bn_32_set_0(to, (n)*2); \
220 bn_32_set_0(to, (n)*2+1); \
221 }
222 #if BN_BITS2 == 32
223 #define bn_cp_32(to, n, from, m) (to)[n] = (from)[m];
224 #define bn_32_set_0(to, n) (to)[n] = (BN_ULONG)0;
225 #elif BN_BITS2 == 16
226 #define bn_cp_32(to, n, from, m) \
227 { \
228 (to)[(n)*2] = (from)[(m)*2]; \
229 (to)[(n)*2+1] = (from)[(m)*2+1];\
230 }
231 #define bn_32_set_0(to, n) { (to)[(n)*2] = 0; (to)[(n)*2+1] = 0; }
232 #elif BN_BITS2 == 8
233 #define bn_cp_32(to, n, from, m) \
234 { \
235 (to)[(n)*4] = (from)[(m)*4]; \
236 (to)[(n)*4+1] = (from)[(m)*4+1];\
237 (to)[(n)*4+2] = (from)[(m)*4+2];\
238 (to)[(n)*4+3] = (from)[(m)*4+3];\
239 }
240 #define bn_32_set_0(to, n) \
241 { (to)[(n)*4] = (BN_ULONG)0; (to)[(n)*4+1] = (BN_ULONG)0; \
242 (to)[(n)*4+2] = (BN_ULONG)0; (to)[(n)*4+3] = (BN_ULONG)0; }
243 #endif
244 #endif /* BN_BITS2 != 64 */
245
246
247 #define nist_set_192(to, from, a1, a2, a3) \
248 { \
249 if (a3 != 0) bn_cp_64(to, 0, from, (a3) - 3) else bn_64_set_0(to, 0)\
250 bn_cp_64(to, 1, from, (a2) - 3) \
251 if (a1 != 0) bn_cp_64(to, 2, from, (a1) - 3) else bn_64_set_0(to, 2)\
252 }
253
BN_nist_mod_192(BIGNUM * r,const BIGNUM * a,const BIGNUM * field,BN_CTX * ctx)254 int BN_nist_mod_192(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
255 BN_CTX *ctx)
256 {
257 int top = a->top, i;
258 BN_ULONG carry = 0;
259 register BN_ULONG *r_d, *a_d = a->d;
260 BN_ULONG t_d[BN_NIST_192_TOP],
261 buf[BN_NIST_192_TOP];
262
263 i = BN_ucmp(field, a);
264 if (i == 0)
265 {
266 BN_zero(r);
267 return 1;
268 }
269 else if (i > 0)
270 return (r == a) ? 1 : (BN_copy(r ,a) != NULL);
271
272 if (top == BN_NIST_192_TOP)
273 return BN_usub(r, a, field);
274
275 if (r != a)
276 {
277 if (!bn_wexpand(r, BN_NIST_192_TOP))
278 return 0;
279 r_d = r->d;
280 nist_cp_bn(r_d, a_d, BN_NIST_192_TOP);
281 }
282 else
283 r_d = a_d;
284
285 nist_cp_bn_0(buf, a_d + BN_NIST_192_TOP, top - BN_NIST_192_TOP, BN_NIST_192_TOP);
286
287 #if defined(OPENSSL_SYS_VMS) && defined(__DECC)
288 # pragma message save
289 # pragma message disable BADSUBSCRIPT
290 #endif
291
292 nist_set_192(t_d, buf, 0, 3, 3);
293 if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP))
294 ++carry;
295
296 nist_set_192(t_d, buf, 4, 4, 0);
297 if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP))
298 ++carry;
299
300 #if defined(OPENSSL_SYS_VMS) && defined(__DECC)
301 # pragma message restore
302 #endif
303
304 nist_set_192(t_d, buf, 5, 5, 5)
305 if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP))
306 ++carry;
307
308 while (carry)
309 {
310 if (bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP))
311 --carry;
312 }
313 r->top = BN_NIST_192_TOP;
314 bn_correct_top(r);
315 if (BN_ucmp(r, field) >= 0)
316 {
317 bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP);
318 bn_correct_top(r);
319 }
320
321 bn_check_top(r);
322 return 1;
323 }
324
325 #define nist_set_224(to, from, a1, a2, a3, a4, a5, a6, a7) \
326 { \
327 if (a7 != 0) bn_cp_32(to, 0, from, (a7) - 7) else bn_32_set_0(to, 0)\
328 if (a6 != 0) bn_cp_32(to, 1, from, (a6) - 7) else bn_32_set_0(to, 1)\
329 if (a5 != 0) bn_cp_32(to, 2, from, (a5) - 7) else bn_32_set_0(to, 2)\
330 if (a4 != 0) bn_cp_32(to, 3, from, (a4) - 7) else bn_32_set_0(to, 3)\
331 if (a3 != 0) bn_cp_32(to, 4, from, (a3) - 7) else bn_32_set_0(to, 4)\
332 if (a2 != 0) bn_cp_32(to, 5, from, (a2) - 7) else bn_32_set_0(to, 5)\
333 if (a1 != 0) bn_cp_32(to, 6, from, (a1) - 7) else bn_32_set_0(to, 6)\
334 }
335
BN_nist_mod_224(BIGNUM * r,const BIGNUM * a,const BIGNUM * field,BN_CTX * ctx)336 int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
337 BN_CTX *ctx)
338 {
339 #if BN_BITS2 != 64
340 int top = a->top, i;
341 int carry = 0;
342 BN_ULONG *r_d, *a_d = a->d;
343 BN_ULONG t_d[BN_NIST_224_TOP],
344 buf[BN_NIST_224_TOP];
345
346 i = BN_ucmp(field, a);
347 if (i == 0)
348 {
349 BN_zero(r);
350 return 1;
351 }
352 else if (i > 0)
353 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
354
355 if (top == BN_NIST_224_TOP)
356 return BN_usub(r, a, field);
357
358 if (r != a)
359 {
360 if (!bn_wexpand(r, BN_NIST_224_TOP))
361 return 0;
362 r_d = r->d;
363 nist_cp_bn(r_d, a_d, BN_NIST_224_TOP);
364 }
365 else
366 r_d = a_d;
367
368 nist_cp_bn_0(buf, a_d + BN_NIST_224_TOP, top - BN_NIST_224_TOP, BN_NIST_224_TOP);
369
370 nist_set_224(t_d, buf, 10, 9, 8, 7, 0, 0, 0);
371 if (bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP))
372 ++carry;
373 nist_set_224(t_d, buf, 0, 13, 12, 11, 0, 0, 0);
374 if (bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP))
375 ++carry;
376 nist_set_224(t_d, buf, 13, 12, 11, 10, 9, 8, 7);
377 if (bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP))
378 --carry;
379 nist_set_224(t_d, buf, 0, 0, 0, 0, 13, 12, 11);
380 if (bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP))
381 --carry;
382
383 if (carry > 0)
384 while (carry)
385 {
386 if (bn_sub_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP))
387 --carry;
388 }
389 else if (carry < 0)
390 while (carry)
391 {
392 if (bn_add_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP))
393 ++carry;
394 }
395
396 r->top = BN_NIST_224_TOP;
397 bn_correct_top(r);
398 if (BN_ucmp(r, field) >= 0)
399 {
400 bn_sub_words(r_d, r_d, _nist_p_224, BN_NIST_224_TOP);
401 bn_correct_top(r);
402 }
403 bn_check_top(r);
404 return 1;
405 #else
406 return 0;
407 #endif
408 }
409
410 #if BN_BITS2 != 64
_init_256_data(void)411 static void _init_256_data(void)
412 {
413 int i;
414 BN_ULONG *tmp1 = _256_data;
415 const BN_ULONG *tmp2 = tmp1;
416
417 memcpy(tmp1, _nist_p_256, BN_NIST_256_TOP * sizeof(BN_ULONG));
418 tmp1 += BN_NIST_256_TOP;
419
420 for (i=0; i<5; i++)
421 {
422 bn_add_words(tmp1, _nist_p_256, tmp2, BN_NIST_256_TOP);
423 tmp2 = tmp1;
424 tmp1 += BN_NIST_256_TOP;
425 }
426 _is_set_256_data = 1;
427 }
428 #endif
429
430 #define nist_set_256(to, from, a1, a2, a3, a4, a5, a6, a7, a8) \
431 { \
432 if (a8 != 0) bn_cp_32(to, 0, from, (a8) - 8) else bn_32_set_0(to, 0)\
433 if (a7 != 0) bn_cp_32(to, 1, from, (a7) - 8) else bn_32_set_0(to, 1)\
434 if (a6 != 0) bn_cp_32(to, 2, from, (a6) - 8) else bn_32_set_0(to, 2)\
435 if (a5 != 0) bn_cp_32(to, 3, from, (a5) - 8) else bn_32_set_0(to, 3)\
436 if (a4 != 0) bn_cp_32(to, 4, from, (a4) - 8) else bn_32_set_0(to, 4)\
437 if (a3 != 0) bn_cp_32(to, 5, from, (a3) - 8) else bn_32_set_0(to, 5)\
438 if (a2 != 0) bn_cp_32(to, 6, from, (a2) - 8) else bn_32_set_0(to, 6)\
439 if (a1 != 0) bn_cp_32(to, 7, from, (a1) - 8) else bn_32_set_0(to, 7)\
440 }
441
BN_nist_mod_256(BIGNUM * r,const BIGNUM * a,const BIGNUM * field,BN_CTX * ctx)442 int BN_nist_mod_256(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
443 BN_CTX *ctx)
444 {
445 #if BN_BITS2 != 64
446 int i, top = a->top;
447 int carry = 0;
448 register BN_ULONG *a_d = a->d, *r_d;
449 BN_ULONG t_d[BN_NIST_256_TOP],
450 t_d2[BN_NIST_256_TOP],
451 buf[BN_NIST_256_TOP];
452
453 if (!_is_set_256_data)
454 {
455 CRYPTO_w_lock(CRYPTO_LOCK_BN);
456
457 if (!_is_set_256_data)
458 _init_256_data();
459
460 CRYPTO_w_unlock(CRYPTO_LOCK_BN);
461 }
462
463 i = BN_ucmp(field, a);
464 if (i == 0)
465 {
466 BN_zero(r);
467 return 1;
468 }
469 else if (i > 0)
470 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
471
472 if (top == BN_NIST_256_TOP)
473 return BN_usub(r, a, field);
474
475 if (r != a)
476 {
477 if (!bn_wexpand(r, BN_NIST_256_TOP))
478 return 0;
479 r_d = r->d;
480 nist_cp_bn(r_d, a_d, BN_NIST_256_TOP);
481 }
482 else
483 r_d = a_d;
484
485 nist_cp_bn_0(buf, a_d + BN_NIST_256_TOP, top - BN_NIST_256_TOP, BN_NIST_256_TOP);
486
487 /*S1*/
488 nist_set_256(t_d, buf, 15, 14, 13, 12, 11, 0, 0, 0);
489 /*S2*/
490 nist_set_256(t_d2,buf, 0, 15, 14, 13, 12, 0, 0, 0);
491 if (bn_add_words(t_d, t_d, t_d2, BN_NIST_256_TOP))
492 carry = 2;
493 /* left shift */
494 {
495 register BN_ULONG *ap,t,c;
496 ap = t_d;
497 c=0;
498 for (i = BN_NIST_256_TOP; i != 0; --i)
499 {
500 t= *ap;
501 *(ap++)=((t<<1)|c)&BN_MASK2;
502 c=(t & BN_TBIT)?1:0;
503 }
504 if (c)
505 ++carry;
506 }
507
508 if (bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP))
509 ++carry;
510 /*S3*/
511 nist_set_256(t_d, buf, 15, 14, 0, 0, 0, 10, 9, 8);
512 if (bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP))
513 ++carry;
514 /*S4*/
515 nist_set_256(t_d, buf, 8, 13, 15, 14, 13, 11, 10, 9);
516 if (bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP))
517 ++carry;
518 /*D1*/
519 nist_set_256(t_d, buf, 10, 8, 0, 0, 0, 13, 12, 11);
520 if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP))
521 --carry;
522 /*D2*/
523 nist_set_256(t_d, buf, 11, 9, 0, 0, 15, 14, 13, 12);
524 if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP))
525 --carry;
526 /*D3*/
527 nist_set_256(t_d, buf, 12, 0, 10, 9, 8, 15, 14, 13);
528 if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP))
529 --carry;
530 /*D4*/
531 nist_set_256(t_d, buf, 13, 0, 11, 10, 9, 0, 15, 14);
532 if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP))
533 --carry;
534
535 if (carry)
536 {
537 if (carry > 0)
538 bn_sub_words(r_d, r_d, _256_data + BN_NIST_256_TOP *
539 --carry, BN_NIST_256_TOP);
540 else
541 {
542 carry = -carry;
543 bn_add_words(r_d, r_d, _256_data + BN_NIST_256_TOP *
544 --carry, BN_NIST_256_TOP);
545 }
546 }
547
548 r->top = BN_NIST_256_TOP;
549 bn_correct_top(r);
550 if (BN_ucmp(r, field) >= 0)
551 {
552 bn_sub_words(r_d, r_d, _nist_p_256, BN_NIST_256_TOP);
553 bn_correct_top(r);
554 }
555 bn_check_top(r);
556 return 1;
557 #else
558 return 0;
559 #endif
560 }
561
562 #if BN_BITS2 != 64
_init_384_data(void)563 static void _init_384_data(void)
564 {
565 int i;
566 BN_ULONG *tmp1 = _384_data;
567 const BN_ULONG *tmp2 = tmp1;
568
569 memcpy(tmp1, _nist_p_384, BN_NIST_384_TOP * sizeof(BN_ULONG));
570 tmp1 += BN_NIST_384_TOP;
571
572 for (i=0; i<7; i++)
573 {
574 bn_add_words(tmp1, _nist_p_384, tmp2, BN_NIST_384_TOP);
575 tmp2 = tmp1;
576 tmp1 += BN_NIST_384_TOP;
577 }
578 _is_set_384_data = 1;
579 }
580 #endif
581
582 #define nist_set_384(to,from,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12) \
583 { \
584 if (a12 != 0) bn_cp_32(to, 0, from, (a12) - 12) else bn_32_set_0(to, 0)\
585 if (a11 != 0) bn_cp_32(to, 1, from, (a11) - 12) else bn_32_set_0(to, 1)\
586 if (a10 != 0) bn_cp_32(to, 2, from, (a10) - 12) else bn_32_set_0(to, 2)\
587 if (a9 != 0) bn_cp_32(to, 3, from, (a9) - 12) else bn_32_set_0(to, 3)\
588 if (a8 != 0) bn_cp_32(to, 4, from, (a8) - 12) else bn_32_set_0(to, 4)\
589 if (a7 != 0) bn_cp_32(to, 5, from, (a7) - 12) else bn_32_set_0(to, 5)\
590 if (a6 != 0) bn_cp_32(to, 6, from, (a6) - 12) else bn_32_set_0(to, 6)\
591 if (a5 != 0) bn_cp_32(to, 7, from, (a5) - 12) else bn_32_set_0(to, 7)\
592 if (a4 != 0) bn_cp_32(to, 8, from, (a4) - 12) else bn_32_set_0(to, 8)\
593 if (a3 != 0) bn_cp_32(to, 9, from, (a3) - 12) else bn_32_set_0(to, 9)\
594 if (a2 != 0) bn_cp_32(to, 10, from, (a2) - 12) else bn_32_set_0(to, 10)\
595 if (a1 != 0) bn_cp_32(to, 11, from, (a1) - 12) else bn_32_set_0(to, 11)\
596 }
597
BN_nist_mod_384(BIGNUM * r,const BIGNUM * a,const BIGNUM * field,BN_CTX * ctx)598 int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
599 BN_CTX *ctx)
600 {
601 #if BN_BITS2 != 64
602 int i, top = a->top;
603 int carry = 0;
604 register BN_ULONG *r_d, *a_d = a->d;
605 BN_ULONG t_d[BN_NIST_384_TOP],
606 buf[BN_NIST_384_TOP];
607
608 if (!_is_set_384_data)
609 {
610 CRYPTO_w_lock(CRYPTO_LOCK_BN);
611
612 if (!_is_set_384_data)
613 _init_384_data();
614
615 CRYPTO_w_unlock(CRYPTO_LOCK_BN);
616 }
617
618 i = BN_ucmp(field, a);
619 if (i == 0)
620 {
621 BN_zero(r);
622 return 1;
623 }
624 else if (i > 0)
625 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
626
627 if (top == BN_NIST_384_TOP)
628 return BN_usub(r, a, field);
629
630 if (r != a)
631 {
632 if (!bn_wexpand(r, BN_NIST_384_TOP))
633 return 0;
634 r_d = r->d;
635 nist_cp_bn(r_d, a_d, BN_NIST_384_TOP);
636 }
637 else
638 r_d = a_d;
639
640 nist_cp_bn_0(buf, a_d + BN_NIST_384_TOP, top - BN_NIST_384_TOP, BN_NIST_384_TOP);
641
642 /*S1*/
643 nist_set_256(t_d, buf, 0, 0, 0, 0, 0, 23-4, 22-4, 21-4);
644 /* left shift */
645 {
646 register BN_ULONG *ap,t,c;
647 ap = t_d;
648 c=0;
649 for (i = BN_NIST_256_TOP; i != 0; --i)
650 {
651 t= *ap;
652 *(ap++)=((t<<1)|c)&BN_MASK2;
653 c=(t & BN_TBIT)?1:0;
654 }
655 }
656 if (bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2),
657 t_d, BN_NIST_256_TOP))
658 ++carry;
659 /*S2 */
660 if (bn_add_words(r_d, r_d, buf, BN_NIST_384_TOP))
661 ++carry;
662 /*S3*/
663 nist_set_384(t_d,buf,20,19,18,17,16,15,14,13,12,23,22,21);
664 if (bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP))
665 ++carry;
666 /*S4*/
667 nist_set_384(t_d,buf,19,18,17,16,15,14,13,12,20,0,23,0);
668 if (bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP))
669 ++carry;
670 /*S5*/
671 nist_set_256(t_d, buf, 0, 0, 0, 0, 23-4, 22-4, 21-4, 20-4);
672 if (bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2),
673 t_d, BN_NIST_256_TOP))
674 ++carry;
675 /*S6*/
676 nist_set_384(t_d,buf,0,0,0,0,0,0,23,22,21,0,0,20);
677 if (bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP))
678 ++carry;
679 /*D1*/
680 nist_set_384(t_d,buf,22,21,20,19,18,17,16,15,14,13,12,23);
681 if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP))
682 --carry;
683 /*D2*/
684 nist_set_384(t_d,buf,0,0,0,0,0,0,0,23,22,21,20,0);
685 if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP))
686 --carry;
687 /*D3*/
688 nist_set_384(t_d,buf,0,0,0,0,0,0,0,23,23,0,0,0);
689 if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP))
690 --carry;
691
692 if (carry)
693 {
694 if (carry > 0)
695 bn_sub_words(r_d, r_d, _384_data + BN_NIST_384_TOP *
696 --carry, BN_NIST_384_TOP);
697 else
698 {
699 carry = -carry;
700 bn_add_words(r_d, r_d, _384_data + BN_NIST_384_TOP *
701 --carry, BN_NIST_384_TOP);
702 }
703 }
704
705 r->top = BN_NIST_384_TOP;
706 bn_correct_top(r);
707 if (BN_ucmp(r, field) >= 0)
708 {
709 bn_sub_words(r_d, r_d, _nist_p_384, BN_NIST_384_TOP);
710 bn_correct_top(r);
711 }
712 bn_check_top(r);
713 return 1;
714 #else
715 return 0;
716 #endif
717 }
718
BN_nist_mod_521(BIGNUM * r,const BIGNUM * a,const BIGNUM * field,BN_CTX * ctx)719 int BN_nist_mod_521(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
720 BN_CTX *ctx)
721 {
722 #if BN_BITS2 == 64
723 #define BN_NIST_521_TOP_MASK (BN_ULONG)0x1FF
724 #elif BN_BITS2 == 32
725 #define BN_NIST_521_TOP_MASK (BN_ULONG)0x1FF
726 #elif BN_BITS2 == 16
727 #define BN_NIST_521_TOP_MASK (BN_ULONG)0x1FF
728 #elif BN_BITS2 == 8
729 #define BN_NIST_521_TOP_MASK (BN_ULONG)0x1
730 #endif
731 int top, ret = 0;
732 BN_ULONG *r_d;
733 BIGNUM *tmp;
734
735 /* check whether a reduction is necessary */
736 top = a->top;
737 if (top < BN_NIST_521_TOP || ( top == BN_NIST_521_TOP &&
738 (!(a->d[BN_NIST_521_TOP-1] & ~(BN_NIST_521_TOP_MASK)))))
739 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
740
741 BN_CTX_start(ctx);
742 tmp = BN_CTX_get(ctx);
743 if (!tmp)
744 goto err;
745
746 if (!bn_wexpand(tmp, BN_NIST_521_TOP))
747 goto err;
748 nist_cp_bn(tmp->d, a->d, BN_NIST_521_TOP);
749
750 tmp->top = BN_NIST_521_TOP;
751 tmp->d[BN_NIST_521_TOP-1] &= BN_NIST_521_TOP_MASK;
752 bn_correct_top(tmp);
753
754 if (!BN_rshift(r, a, 521))
755 goto err;
756
757 if (!BN_uadd(r, tmp, r))
758 goto err;
759 top = r->top;
760 r_d = r->d;
761 if (top == BN_NIST_521_TOP &&
762 (r_d[BN_NIST_521_TOP-1] & ~(BN_NIST_521_TOP_MASK)))
763 {
764 BN_NIST_ADD_ONE(r_d)
765 r_d[BN_NIST_521_TOP-1] &= BN_NIST_521_TOP_MASK;
766 }
767 bn_correct_top(r);
768
769 ret = 1;
770 err:
771 BN_CTX_end(ctx);
772
773 bn_check_top(r);
774 return ret;
775 }
776