crypto/bn/bn_nist.c

   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
 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
 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
 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
 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
 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 #endif
 180
 181 #define BN_NIST_ADD_ONE(a)      while (!(*(a)=(*(a)+1)&BN_MASK2)) ++(a);
 182
 183 static void nist_cp_bn_0(BN_ULONG *buf, BN_ULONG *a, int top, int max)
 184         {
 185         int i;
 186         BN_ULONG *_tmp1 = (buf), *_tmp2 = (a);
 187         for (i = (top); i != 0; i--)
 188                 *_tmp1++ = *_tmp2++;
 189         for (i = (max) - (top); i != 0; i--)
 190                 *_tmp1++ = (BN_ULONG) 0;
 191         }
 192
 193 static void nist_cp_bn(BN_ULONG *buf, BN_ULONG *a, int top)
 194         {
 195         int i;
 196         BN_ULONG *_tmp1 = (buf), *_tmp2 = (a);
 197         for (i = (top); i != 0; i--)
 198                 *_tmp1++ = *_tmp2++;
 199         }
 200
 201 #if BN_BITS2 == 64
 202 #define bn_cp_64(to, n, from, m)        (to)[n] = (from)[m];
 203 #define bn_64_set_0(to, n)              (to)[n] = (BN_ULONG)0;
 204 /* TBD */
 205 #define bn_cp_32(to, n, from, m)        (to)[n] = (from)[m];
 206 #define bn_32_set_0(to, n)              (to)[n] = (BN_ULONG)0;
 207 #else
 208 #define bn_cp_64(to, n, from, m) \
 209         { \
 210         bn_cp_32(to, (n)*2, from, (m)*2); \
 211         bn_cp_32(to, (n)*2+1, from, (m)*2+1); \
 212         }
 213 #define bn_64_set_0(to, n) \
 214         { \
 215         bn_32_set_0(to, (n)*2); \
 216         bn_32_set_0(to, (n)*2+1); \
 217         }
 218 #if BN_BITS2 == 32
 219 #define bn_cp_32(to, n, from, m)        (to)[n] = (from)[m];
 220 #define bn_32_set_0(to, n)              (to)[n] = (BN_ULONG)0;
 221 #elif BN_BITS2 == 16
 222 #define bn_cp_32(to, n, from, m) \
 223         { \
 224         (to)[(n)*2]   = (from)[(m)*2];  \
 225         (to)[(n)*2+1] = (from)[(m)*2+1];\
 226         }
 227 #define bn_32_set_0(to, n) { (to)[(n)*2] = 0; (to)[(n)*2+1] = 0; }
 228 #elif BN_BITS2 == 8
 229 #define bn_cp_32(to, n, from, m) \
 230         { \
 231         (to)[(n)*4]   = (from)[(m)*4];  \
 232         (to)[(n)*4+1] = (from)[(m)*4+1];\
 233         (to)[(n)*4+2] = (from)[(m)*4+2];\
 234         (to)[(n)*4+3] = (from)[(m)*4+3];\
 235         }
 236 #define bn_32_set_0(to, n) \
 237         { (to)[(n)*4]   = (BN_ULONG)0; (to)[(n)*4+1] = (BN_ULONG)0; \
 238           (to)[(n)*4+2] = (BN_ULONG)0; (to)[(n)*4+3] = (BN_ULONG)0; }
 239 #endif
 240 #endif /* BN_BITS2 != 64 */
 241
 242
 243 #define nist_set_192(to, from, a1, a2, a3) \
 244         { \
 245         if (a3 != 0) bn_cp_64(to, 0, from, (a3) - 3) else bn_64_set_0(to, 0)\
 246         bn_cp_64(to, 1, from, (a2) - 3) \
 247         if (a1 != 0) bn_cp_64(to, 2, from, (a1) - 3) else bn_64_set_0(to, 2)\
 248         }
 249
 250 int BN_nist_mod_192(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 251         BN_CTX *ctx)
 252         {
 253         int      top = a->top, i;
 254         register BN_ULONG *r_d, *a_d = a->d;
 255         BN_ULONG t_d[BN_NIST_192_TOP],
 256                  buf[BN_NIST_192_TOP];
 257
 258         i = BN_ucmp(field, a);
 259         if (i == 0)
 260                 {
 261                 BN_zero(r);
 262                 return 1;
 263                 }
 264         else if (i > 0)
 265                 return (r == a) ? 1 : (BN_copy(r ,a) != NULL);
 266
 267         if (top == BN_NIST_192_TOP)
 268                 return BN_usub(r, a, field);
 269
 270         if (r != a)
 271                 {
 272                 if (!bn_wexpand(r, BN_NIST_192_TOP))
 273                         return 0;
 274                 r_d = r->d;
 275                 nist_cp_bn(r_d, a_d, BN_NIST_192_TOP);
 276                 }
 277         else
 278                 r_d = a_d;
 279
 280         nist_cp_bn_0(buf, a_d + BN_NIST_192_TOP, top - BN_NIST_192_TOP, BN_NIST_192_TOP);
 281
 282 #if defined(OPENSSL_SYS_VMS) && defined(__DECC)
 283 # pragma message save
 284 # pragma message disable BADSUBSCRIPT
 285 #endif
 286
 287         nist_set_192(t_d, buf, 0, 3, 3);
 288         if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP))
 289                 bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP);
 290
 291         nist_set_192(t_d, buf, 4, 4, 0);
 292         if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP))
 293                 bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP);
 294
 295 #if defined(OPENSSL_SYS_VMS) && defined(__DECC)
 296 # pragma message restore
 297 #endif
 298
 299         nist_set_192(t_d, buf, 5, 5, 5)
 300         if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP))
 301                 bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP);
 302
 303         r->top = BN_NIST_192_TOP;
 304         bn_correct_top(r);
 305         if (BN_ucmp(r, field) >= 0)
 306                 {
 307                 bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP);
 308                 bn_correct_top(r);
 309                 }
 310
 311         bn_check_top(r);
 312         return 1;
 313         }
 314
 315 #define nist_set_224(to, from, a1, a2, a3, a4, a5, a6, a7) \
 316         { \
 317         if (a7 != 0) bn_cp_32(to, 0, from, (a7) - 7) else bn_32_set_0(to, 0)\
 318         if (a6 != 0) bn_cp_32(to, 1, from, (a6) - 7) else bn_32_set_0(to, 1)\
 319         if (a5 != 0) bn_cp_32(to, 2, from, (a5) - 7) else bn_32_set_0(to, 2)\
 320         if (a4 != 0) bn_cp_32(to, 3, from, (a4) - 7) else bn_32_set_0(to, 3)\
 321         if (a3 != 0) bn_cp_32(to, 4, from, (a3) - 7) else bn_32_set_0(to, 4)\
 322         if (a2 != 0) bn_cp_32(to, 5, from, (a2) - 7) else bn_32_set_0(to, 5)\
 323         if (a1 != 0) bn_cp_32(to, 6, from, (a1) - 7) else bn_32_set_0(to, 6)\
 324         }
 325
 326 int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 327         BN_CTX *ctx)
 328         {
 329 #if BN_BITS2 == 32
 330         int     top = a->top, i;
 331         BN_ULONG *r_d, *a_d = a->d;
 332         BN_ULONG t_d[BN_NIST_224_TOP],
 333                  buf[BN_NIST_224_TOP];
 334
 335         i = BN_ucmp(field, a);
 336         if (i == 0)
 337                 {
 338                 BN_zero(r);
 339                 return 1;
 340                 }
 341         else if (i > 0)
 342                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
 343
 344         if (top == BN_NIST_224_TOP)
 345                 return BN_usub(r, a, field);
 346
 347         if (r != a)
 348                 {
 349                 if (!bn_wexpand(r, BN_NIST_224_TOP))
 350                         return 0;
 351                 r_d = r->d;
 352                 nist_cp_bn(r_d, a_d, BN_NIST_224_TOP);
 353                 }
 354         else
 355                 r_d = a_d;
 356
 357         nist_cp_bn_0(buf, a_d + BN_NIST_224_TOP, top - BN_NIST_224_TOP, BN_NIST_224_TOP);
 358
 359         nist_set_224(t_d, buf, 10, 9, 8, 7, 0, 0, 0);
 360         if (bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP))
 361                 bn_sub_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP);
 362         nist_set_224(t_d, buf, 0, 13, 12, 11, 0, 0, 0);
 363         if (bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP))
 364                 bn_sub_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP);
 365         nist_set_224(t_d, buf, 13, 12, 11, 10, 9, 8, 7);
 366         if (bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP))
 367                 bn_add_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP);
 368         nist_set_224(t_d, buf, 0, 0, 0, 0, 13, 12, 11);
 369         if (bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP))
 370                 bn_add_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP);
 371
 372         r->top = BN_NIST_224_TOP;
 373         bn_correct_top(r);
 374         if (BN_ucmp(r, field) >= 0)
 375                 {
 376                 bn_sub_words(r_d, r_d, _nist_p_224, BN_NIST_224_TOP);
 377                 bn_correct_top(r);
 378                 }
 379         bn_check_top(r);
 380         return 1;
 381 #else
 382         return 0;
 383 #endif
 384         }
 385
 386 #if BN_BITS2 == 32
 387 static void _init_256_data(void)
 388         {
 389         int     i;
 390         BN_ULONG *tmp1 = _256_data;
 391         const BN_ULONG *tmp2 = tmp1;
 392
 393         memcpy(tmp1, _nist_p_256, BN_NIST_256_TOP * sizeof(BN_ULONG));
 394         tmp1 += BN_NIST_256_TOP;
 395
 396         for (i=0; i<5; i++)
 397                 {
 398                 bn_add_words(tmp1, _nist_p_256, tmp2, BN_NIST_256_TOP);
 399                 tmp2  = tmp1;
 400                 tmp1 += BN_NIST_256_TOP;
 401                 }
 402         _is_set_256_data = 1;
 403         }
 404 #endif
 405
 406 #define nist_set_256(to, from, a1, a2, a3, a4, a5, a6, a7, a8) \
 407         { \
 408         if (a8 != 0) bn_cp_32(to, 0, from, (a8) - 8) else bn_32_set_0(to, 0)\
 409         if (a7 != 0) bn_cp_32(to, 1, from, (a7) - 8) else bn_32_set_0(to, 1)\
 410         if (a6 != 0) bn_cp_32(to, 2, from, (a6) - 8) else bn_32_set_0(to, 2)\
 411         if (a5 != 0) bn_cp_32(to, 3, from, (a5) - 8) else bn_32_set_0(to, 3)\
 412         if (a4 != 0) bn_cp_32(to, 4, from, (a4) - 8) else bn_32_set_0(to, 4)\
 413         if (a3 != 0) bn_cp_32(to, 5, from, (a3) - 8) else bn_32_set_0(to, 5)\
 414         if (a2 != 0) bn_cp_32(to, 6, from, (a2) - 8) else bn_32_set_0(to, 6)\
 415         if (a1 != 0) bn_cp_32(to, 7, from, (a1) - 8) else bn_32_set_0(to, 7)\
 416         }
 417
 418 int BN_nist_mod_256(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 419         BN_CTX *ctx)
 420         {
 421 #if BN_BITS2 == 32
 422         int     i, top = a->top;
 423         int     carry = 0;
 424         register BN_ULONG *a_d = a->d, *r_d;
 425         BN_ULONG t_d[BN_NIST_256_TOP],
 426                  t_d2[BN_NIST_256_TOP],
 427                  buf[BN_NIST_256_TOP];
 428
 429         if (!_is_set_256_data)
 430                 {
 431                 CRYPTO_w_lock(CRYPTO_LOCK_BN);
 432
 433                 if (!_is_set_256_data)
 434                         _init_256_data();
 435
 436                 CRYPTO_w_unlock(CRYPTO_LOCK_BN);
 437                 }
 438
 439         i = BN_ucmp(field, a);
 440         if (i == 0)
 441                 {
 442                 BN_zero(r);
 443                 return 1;
 444                 }
 445         else if (i > 0)
 446                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
 447
 448         if (top == BN_NIST_256_TOP)
 449                 return BN_usub(r, a, field);
 450
 451         if (r != a)
 452                 {
 453                 if (!bn_wexpand(r, BN_NIST_256_TOP))
 454                         return 0;
 455                 r_d = r->d;
 456                 nist_cp_bn(r_d, a_d, BN_NIST_256_TOP);
 457                 }
 458         else
 459                 r_d = a_d;
 460
 461         nist_cp_bn_0(buf, a_d + BN_NIST_256_TOP, top - BN_NIST_256_TOP, BN_NIST_256_TOP);
 462
 463         /*S1*/
 464         nist_set_256(t_d, buf, 15, 14, 13, 12, 11, 0, 0, 0);
 465         /*S2*/
 466         nist_set_256(t_d2,buf, 0, 15, 14, 13, 12, 0, 0, 0);
 467         carry = bn_add_words(t_d, t_d, t_d2, BN_NIST_256_TOP);
 468         /* left shift */
 469                 {
 470                 register BN_ULONG *ap,t,c;
 471                 ap = t_d;
 472                 c=0;
 473                 for (i = BN_NIST_256_TOP; i != 0; --i)
 474                         {
 475                         t= *ap;
 476                         *(ap++)=((t<<1)|c)&BN_MASK2;
 477                         c=(t & BN_TBIT)?1:0;
 478                         }
 479                 carry <<= 1;
 480                 carry  |= c;
 481                 }
 482
 483         carry += bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 484         /*S3*/
 485         nist_set_256(t_d, buf, 15, 14, 0, 0, 0, 10, 9, 8);
 486         carry += bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 487         /*S4*/
 488         nist_set_256(t_d, buf, 8, 13, 15, 14, 13, 11, 10, 9);
 489         carry += bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 490
 491         if (carry)
 492                 bn_sub_words(r_d, r_d, _256_data + BN_NIST_256_TOP *
 493                                 (carry-1), BN_NIST_256_TOP);
 494
 495         /*D1*/
 496         nist_set_256(t_d, buf, 10, 8, 0, 0, 0, 13, 12, 11);
 497         carry = bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 498         /*D2*/
 499         nist_set_256(t_d, buf, 11, 9, 0, 0, 15, 14, 13, 12);
 500         carry += bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 501         /*D3*/
 502         nist_set_256(t_d, buf, 12, 0, 10, 9, 8, 15, 14, 13);
 503         carry += bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 504         /*D4*/
 505         nist_set_256(t_d, buf, 13, 0, 11, 10, 9, 0, 15, 14);
 506         carry += bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 507
 508         if (carry)
 509                 bn_add_words(r_d, r_d, _256_data + BN_NIST_256_TOP *
 510                                 (carry-1), BN_NIST_256_TOP);
 511
 512         r->top = BN_NIST_256_TOP;
 513         bn_correct_top(r);
 514         if (BN_ucmp(r, field) >= 0)
 515                 {
 516                 bn_sub_words(r_d, r_d, _nist_p_256, BN_NIST_256_TOP);
 517                 bn_correct_top(r);
 518                 }
 519         bn_check_top(r);
 520         return 1;
 521 #else
 522         return 0;
 523 #endif
 524         }
 525
 526 #define nist_set_384(to,from,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12) \
 527         { \
 528         if (a12 != 0) bn_cp_32(to, 0, from,  (a12) - 12) else bn_32_set_0(to, 0)\
 529         if (a11 != 0) bn_cp_32(to, 1, from,  (a11) - 12) else bn_32_set_0(to, 1)\
 530         if (a10 != 0) bn_cp_32(to, 2, from,  (a10) - 12) else bn_32_set_0(to, 2)\
 531         if (a9 != 0)  bn_cp_32(to, 3, from,  (a9) - 12)  else bn_32_set_0(to, 3)\
 532         if (a8 != 0)  bn_cp_32(to, 4, from,  (a8) - 12)  else bn_32_set_0(to, 4)\
 533         if (a7 != 0)  bn_cp_32(to, 5, from,  (a7) - 12)  else bn_32_set_0(to, 5)\
 534         if (a6 != 0)  bn_cp_32(to, 6, from,  (a6) - 12)  else bn_32_set_0(to, 6)\
 535         if (a5 != 0)  bn_cp_32(to, 7, from,  (a5) - 12)  else bn_32_set_0(to, 7)\
 536         if (a4 != 0)  bn_cp_32(to, 8, from,  (a4) - 12)  else bn_32_set_0(to, 8)\
 537         if (a3 != 0)  bn_cp_32(to, 9, from,  (a3) - 12)  else bn_32_set_0(to, 9)\
 538         if (a2 != 0)  bn_cp_32(to, 10, from, (a2) - 12)  else bn_32_set_0(to, 10)\
 539         if (a1 != 0)  bn_cp_32(to, 11, from, (a1) - 12)  else bn_32_set_0(to, 11)\
 540         }
 541
 542 int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 543         BN_CTX *ctx)
 544         {
 545 #if BN_BITS2 == 32
 546         int     i, top = a->top;
 547         int     carry = 0;
 548         register BN_ULONG *r_d, *a_d = a->d;
 549         BN_ULONG t_d[BN_NIST_384_TOP],
 550                  buf[BN_NIST_384_TOP],
 551                  c_d[BN_NIST_384_TOP],
 552                 *res;
 553         size_t   mask;
 554
 555         i = BN_ucmp(field, a);
 556         if (i == 0)
 557                 {
 558                 BN_zero(r);
 559                 return 1;
 560                 }
 561         else if (i > 0)
 562                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
 563
 564         if (top == BN_NIST_384_TOP)
 565                 return BN_usub(r, a, field);
 566
 567         if (r != a)
 568                 {
 569                 if (!bn_wexpand(r, BN_NIST_384_TOP))
 570                         return 0;
 571                 r_d = r->d;
 572                 nist_cp_bn(r_d, a_d, BN_NIST_384_TOP);
 573                 }
 574         else
 575                 r_d = a_d;
 576
 577         nist_cp_bn_0(buf, a_d + BN_NIST_384_TOP, top - BN_NIST_384_TOP, BN_NIST_384_TOP);
 578
 579         /*S1*/
 580         nist_set_256(t_d, buf, 0, 0, 0, 0, 0, 23-4, 22-4, 21-4);
 581                 /* left shift */
 582                 {
 583                 register BN_ULONG *ap,t,c;
 584                 ap = t_d;
 585                 c=0;
 586                 for (i = 3; i != 0; --i)
 587                         {
 588                         t= *ap;
 589                         *(ap++)=((t<<1)|c)&BN_MASK2;
 590                         c=(t & BN_TBIT)?1:0;
 591                         }
 592                 *ap=c;
 593                 }
 594         carry = bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2),
 595                 t_d, BN_NIST_256_TOP);
 596         /* this is equivalent to if (result >= module) */
 597         mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 598         mask = ~mask | (0-(size_t)carry);
 599         res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
 600
 601         /*S2 */
 602         carry = bn_add_words(r_d, res, buf, BN_NIST_384_TOP);
 603         mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 604         mask = ~mask | (0-(size_t)carry);
 605         res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
 606
 607         /*S3*/
 608         nist_set_384(t_d,buf,20,19,18,17,16,15,14,13,12,23,22,21);
 609         carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP);
 610         mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 611         mask = ~mask | (0-(size_t)carry);
 612         res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
 613
 614         /*S4*/
 615         nist_set_384(t_d,buf,19,18,17,16,15,14,13,12,20,0,23,0);
 616         carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP);
 617         mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 618         mask = ~mask | (0-(size_t)carry);
 619         res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
 620
 621         /*S5*/
 622         nist_set_384(t_d, buf,0,0,0,0,23,22,21,20,0,0,0,0);
 623         carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP);
 624         mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 625         mask = ~mask | (0-(size_t)carry);
 626         res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
 627
 628         /*S6*/
 629         nist_set_384(t_d,buf,0,0,0,0,0,0,23,22,21,0,0,20);
 630         carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP);
 631         mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 632         mask = ~mask | (0-(size_t)carry);
 633         res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
 634
 635         /*D1*/
 636         nist_set_384(t_d,buf,22,21,20,19,18,17,16,15,14,13,12,23);
 637 #if BRANCH_FREE
 638         carry = bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP);
 639         bn_add_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 640         mask = 0-(size_t)carry;
 641         res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
 642 #else
 643         if (bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP))
 644                 bn_add_words(r_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 645 #endif
 646         /*D2*/
 647         nist_set_384(t_d,buf,0,0,0,0,0,0,0,23,22,21,20,0);
 648 #if BRANCH_FREE
 649         carry = bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP);
 650         bn_add_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 651         mask = 0-(size_t)carry;
 652         res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
 653 #else
 654         if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP))
 655                 bn_add_words(r_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 656 #endif
 657         /*D3*/
 658         nist_set_384(t_d,buf,0,0,0,0,0,0,0,23,23,0,0,0);
 659 #if BRANCH_FREE
 660         carry = bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP);
 661         bn_add_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 662         mask = 0-(size_t)carry;
 663         res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
 664
 665         nist_cp_bn(r_d, res, BN_NIST_384_TOP);
 666 #else
 667         if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP))
 668                 bn_add_words(r_d,r_d,_nist_p_384,BN_NIST_384_TOP);
 669 #endif
 670         r->top = BN_NIST_384_TOP;
 671         bn_correct_top(r);
 672
 673         return 1;
 674 #else
 675         return 0;
 676 #endif
 677         }
 678
 679 int BN_nist_mod_521(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 680         BN_CTX *ctx)
 681         {
 682 #if BN_BITS2 == 64
 683 #define BN_NIST_521_TOP_MASK    (BN_ULONG)0x1FF
 684 #elif BN_BITS2 == 32
 685 #define BN_NIST_521_TOP_MASK    (BN_ULONG)0x1FF
 686 #elif BN_BITS2 == 16
 687 #define BN_NIST_521_TOP_MASK    (BN_ULONG)0x1FF
 688 #elif BN_BITS2 == 8
 689 #define BN_NIST_521_TOP_MASK    (BN_ULONG)0x1
 690 #endif
 691         int     top, ret = 0;
 692         BN_ULONG *r_d;
 693         BIGNUM  *tmp;
 694
 695         /* check whether a reduction is necessary */
 696         top = a->top;
 697         if (top < BN_NIST_521_TOP  || ( top == BN_NIST_521_TOP &&
 698            (!(a->d[BN_NIST_521_TOP-1] & ~(BN_NIST_521_TOP_MASK)))))
 699                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
 700
 701         BN_CTX_start(ctx);
 702         tmp = BN_CTX_get(ctx);
 703         if (!tmp)
 704                 goto err;
 705
 706         if (!bn_wexpand(tmp, BN_NIST_521_TOP))
 707                 goto err;
 708         nist_cp_bn(tmp->d, a->d, BN_NIST_521_TOP);
 709
 710         tmp->top = BN_NIST_521_TOP;
 711         tmp->d[BN_NIST_521_TOP-1]  &= BN_NIST_521_TOP_MASK;
 712         bn_correct_top(tmp);
 713
 714         if (!BN_rshift(r, a, 521))
 715                 goto err;
 716
 717         if (!BN_uadd(r, tmp, r))
 718                 goto err;
 719         top = r->top;
 720         r_d = r->d;
 721         if (top == BN_NIST_521_TOP  &&
 722            (r_d[BN_NIST_521_TOP-1] & ~(BN_NIST_521_TOP_MASK)))
 723                 {
 724                 BN_NIST_ADD_ONE(r_d)
 725                 r->d[BN_NIST_521_TOP-1] &= BN_NIST_521_TOP_MASK;
 726                 }
 727         bn_correct_top(r);
 728
 729         ret = 1;
 730 err:
 731         BN_CTX_end(ctx);
 732
 733         bn_check_top(r);
 734         return ret;
 735         }