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
  63 #define BN_NIST_192_TOP (192+BN_BITS2-1)/BN_BITS2
  64 #define BN_NIST_224_TOP (224+BN_BITS2-1)/BN_BITS2
  65 #define BN_NIST_256_TOP (256+BN_BITS2-1)/BN_BITS2
  66 #define BN_NIST_384_TOP (384+BN_BITS2-1)/BN_BITS2
  67 #define BN_NIST_521_TOP (521+BN_BITS2-1)/BN_BITS2
  68
  69 /* pre-computed tables are "carry-less" values of modulus*(i+1) */
  70 #if BN_BITS2 == 64
  71 __fips_constseg
  72 static const BN_ULONG _nist_p_192[][BN_NIST_192_TOP] = {
  73         {0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFEULL,0xFFFFFFFFFFFFFFFFULL},
  74         {0xFFFFFFFFFFFFFFFEULL,0xFFFFFFFFFFFFFFFDULL,0xFFFFFFFFFFFFFFFFULL},
  75         {0xFFFFFFFFFFFFFFFDULL,0xFFFFFFFFFFFFFFFCULL,0xFFFFFFFFFFFFFFFFULL}
  76         };
  77 __fips_constseg
  78 static const BN_ULONG _nist_p_192_sqr[] = {
  79         0x0000000000000001ULL,0x0000000000000002ULL,0x0000000000000001ULL,
  80         0xFFFFFFFFFFFFFFFEULL,0xFFFFFFFFFFFFFFFDULL,0xFFFFFFFFFFFFFFFFULL
  81         };
  82 __fips_constseg
  83 static const BN_ULONG _nist_p_224[][BN_NIST_224_TOP] = {
  84         {0x0000000000000001ULL,0xFFFFFFFF00000000ULL,
  85          0xFFFFFFFFFFFFFFFFULL,0x00000000FFFFFFFFULL},
  86         {0x0000000000000002ULL,0xFFFFFFFE00000000ULL,
  87          0xFFFFFFFFFFFFFFFFULL,0x00000001FFFFFFFFULL} /* this one is "carry-full" */
  88         };
  89 __fips_constseg
  90 static const BN_ULONG _nist_p_224_sqr[] = {
  91         0x0000000000000001ULL,0xFFFFFFFE00000000ULL,
  92         0xFFFFFFFFFFFFFFFFULL,0x0000000200000000ULL,
  93         0x0000000000000000ULL,0xFFFFFFFFFFFFFFFEULL,
  94         0xFFFFFFFFFFFFFFFFULL
  95         };
  96 __fips_constseg
  97 static const BN_ULONG _nist_p_256[][BN_NIST_256_TOP] = {
  98         {0xFFFFFFFFFFFFFFFFULL,0x00000000FFFFFFFFULL,
  99          0x0000000000000000ULL,0xFFFFFFFF00000001ULL},
 100         {0xFFFFFFFFFFFFFFFEULL,0x00000001FFFFFFFFULL,
 101          0x0000000000000000ULL,0xFFFFFFFE00000002ULL},
 102         {0xFFFFFFFFFFFFFFFDULL,0x00000002FFFFFFFFULL,
 103          0x0000000000000000ULL,0xFFFFFFFD00000003ULL},
 104         {0xFFFFFFFFFFFFFFFCULL,0x00000003FFFFFFFFULL,
 105          0x0000000000000000ULL,0xFFFFFFFC00000004ULL},
 106         {0xFFFFFFFFFFFFFFFBULL,0x00000004FFFFFFFFULL,
 107          0x0000000000000000ULL,0xFFFFFFFB00000005ULL},
 108         };
 109 __fips_constseg
 110 static const BN_ULONG _nist_p_256_sqr[] = {
 111         0x0000000000000001ULL,0xFFFFFFFE00000000ULL,
 112         0xFFFFFFFFFFFFFFFFULL,0x00000001FFFFFFFEULL,
 113         0x00000001FFFFFFFEULL,0x00000001FFFFFFFEULL,
 114         0xFFFFFFFE00000001ULL,0xFFFFFFFE00000002ULL
 115         };
 116 __fips_constseg
 117 static const BN_ULONG _nist_p_384[][BN_NIST_384_TOP] = {
 118         {0x00000000FFFFFFFFULL,0xFFFFFFFF00000000ULL,0xFFFFFFFFFFFFFFFEULL,
 119          0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL},
 120         {0x00000001FFFFFFFEULL,0xFFFFFFFE00000000ULL,0xFFFFFFFFFFFFFFFDULL,
 121          0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL},
 122         {0x00000002FFFFFFFDULL,0xFFFFFFFD00000000ULL,0xFFFFFFFFFFFFFFFCULL,
 123          0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL},
 124         {0x00000003FFFFFFFCULL,0xFFFFFFFC00000000ULL,0xFFFFFFFFFFFFFFFBULL,
 125          0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL},
 126         {0x00000004FFFFFFFBULL,0xFFFFFFFB00000000ULL,0xFFFFFFFFFFFFFFFAULL,
 127          0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL},
 128         };
 129 __fips_constseg
 130 static const BN_ULONG _nist_p_384_sqr[] = {
 131         0xFFFFFFFE00000001ULL,0x0000000200000000ULL,0xFFFFFFFE00000000ULL,
 132         0x0000000200000000ULL,0x0000000000000001ULL,0x0000000000000000ULL,
 133         0x00000001FFFFFFFEULL,0xFFFFFFFE00000000ULL,0xFFFFFFFFFFFFFFFDULL,
 134         0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL
 135         };
 136 __fips_constseg
 137 static const BN_ULONG _nist_p_521[] =
 138         {0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,
 139         0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,
 140         0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,
 141         0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,
 142         0x00000000000001FFULL};
 143 __fips_constseg
 144 static const BN_ULONG _nist_p_521_sqr[] = {
 145         0x0000000000000001ULL,0x0000000000000000ULL,0x0000000000000000ULL,
 146         0x0000000000000000ULL,0x0000000000000000ULL,0x0000000000000000ULL,
 147         0x0000000000000000ULL,0x0000000000000000ULL,0xFFFFFFFFFFFFFC00ULL,
 148         0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,
 149         0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,0xFFFFFFFFFFFFFFFFULL,
 150         0xFFFFFFFFFFFFFFFFULL,0x000000000003FFFFULL
 151         };
 152 #elif BN_BITS2 == 32
 153 __fips_constseg
 154 static const BN_ULONG _nist_p_192[][BN_NIST_192_TOP] = {
 155         {0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFE,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF},
 156         {0xFFFFFFFE,0xFFFFFFFF,0xFFFFFFFD,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF},
 157         {0xFFFFFFFD,0xFFFFFFFF,0xFFFFFFFC,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF}
 158         };
 159 __fips_constseg
 160 static const BN_ULONG _nist_p_192_sqr[] = {
 161         0x00000001,0x00000000,0x00000002,0x00000000,0x00000001,0x00000000,
 162         0xFFFFFFFE,0xFFFFFFFF,0xFFFFFFFD,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF
 163         };
 164 __fips_constseg
 165 static const BN_ULONG _nist_p_224[][BN_NIST_224_TOP] = {
 166         {0x00000001,0x00000000,0x00000000,0xFFFFFFFF,
 167          0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF},
 168         {0x00000002,0x00000000,0x00000000,0xFFFFFFFE,
 169          0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF}
 170         };
 171 __fips_constseg
 172 static const BN_ULONG _nist_p_224_sqr[] = {
 173         0x00000001,0x00000000,0x00000000,0xFFFFFFFE,
 174         0xFFFFFFFF,0xFFFFFFFF,0x00000000,0x00000002,
 175         0x00000000,0x00000000,0xFFFFFFFE,0xFFFFFFFF,
 176         0xFFFFFFFF,0xFFFFFFFF
 177         };
 178 __fips_constseg
 179 static const BN_ULONG _nist_p_256[][BN_NIST_256_TOP] = {
 180         {0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0x00000000,
 181          0x00000000,0x00000000,0x00000001,0xFFFFFFFF},
 182         {0xFFFFFFFE,0xFFFFFFFF,0xFFFFFFFF,0x00000001,
 183          0x00000000,0x00000000,0x00000002,0xFFFFFFFE},
 184         {0xFFFFFFFD,0xFFFFFFFF,0xFFFFFFFF,0x00000002,
 185          0x00000000,0x00000000,0x00000003,0xFFFFFFFD},
 186         {0xFFFFFFFC,0xFFFFFFFF,0xFFFFFFFF,0x00000003,
 187          0x00000000,0x00000000,0x00000004,0xFFFFFFFC},
 188         {0xFFFFFFFB,0xFFFFFFFF,0xFFFFFFFF,0x00000004,
 189          0x00000000,0x00000000,0x00000005,0xFFFFFFFB},
 190         };
 191 __fips_constseg
 192 static const BN_ULONG _nist_p_256_sqr[] = {
 193         0x00000001,0x00000000,0x00000000,0xFFFFFFFE,
 194         0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFE,0x00000001,
 195         0xFFFFFFFE,0x00000001,0xFFFFFFFE,0x00000001,
 196         0x00000001,0xFFFFFFFE,0x00000002,0xFFFFFFFE
 197         };
 198 __fips_constseg
 199 static const BN_ULONG _nist_p_384[][BN_NIST_384_TOP] = {
 200         {0xFFFFFFFF,0x00000000,0x00000000,0xFFFFFFFF,0xFFFFFFFE,0xFFFFFFFF,
 201          0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF},
 202         {0xFFFFFFFE,0x00000001,0x00000000,0xFFFFFFFE,0xFFFFFFFD,0xFFFFFFFF,
 203          0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF},
 204         {0xFFFFFFFD,0x00000002,0x00000000,0xFFFFFFFD,0xFFFFFFFC,0xFFFFFFFF,
 205          0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF},
 206         {0xFFFFFFFC,0x00000003,0x00000000,0xFFFFFFFC,0xFFFFFFFB,0xFFFFFFFF,
 207          0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF},
 208         {0xFFFFFFFB,0x00000004,0x00000000,0xFFFFFFFB,0xFFFFFFFA,0xFFFFFFFF,
 209          0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF},
 210         };
 211 __fips_constseg
 212 static const BN_ULONG _nist_p_384_sqr[] = {
 213         0x00000001,0xFFFFFFFE,0x00000000,0x00000002,0x00000000,0xFFFFFFFE,
 214         0x00000000,0x00000002,0x00000001,0x00000000,0x00000000,0x00000000,
 215         0xFFFFFFFE,0x00000001,0x00000000,0xFFFFFFFE,0xFFFFFFFD,0xFFFFFFFF,
 216         0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF
 217         };
 218 __fips_constseg
 219 static const BN_ULONG _nist_p_521[] = {0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
 220         0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
 221         0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
 222         0xFFFFFFFF,0x000001FF};
 223 __fips_constseg
 224 static const BN_ULONG _nist_p_521_sqr[] = {
 225         0x00000001,0x00000000,0x00000000,0x00000000,0x00000000,0x00000000,
 226         0x00000000,0x00000000,0x00000000,0x00000000,0x00000000,0x00000000,
 227         0x00000000,0x00000000,0x00000000,0x00000000,0xFFFFFC00,0xFFFFFFFF,
 228         0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
 229         0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
 230         0xFFFFFFFF,0xFFFFFFFF,0x0003FFFF
 231         };
 232 #else
 233 #error "unsupported BN_BITS2"
 234 #endif
 235
 236
 237 static const BIGNUM _bignum_nist_p_192 =
 238         {
 239         (BN_ULONG *)_nist_p_192[0],
 240         BN_NIST_192_TOP,
 241         BN_NIST_192_TOP,
 242         0,
 243         BN_FLG_STATIC_DATA
 244         };
 245
 246 static const BIGNUM _bignum_nist_p_224 =
 247         {
 248         (BN_ULONG *)_nist_p_224[0],
 249         BN_NIST_224_TOP,
 250         BN_NIST_224_TOP,
 251         0,
 252         BN_FLG_STATIC_DATA
 253         };
 254
 255 static const BIGNUM _bignum_nist_p_256 =
 256         {
 257         (BN_ULONG *)_nist_p_256[0],
 258         BN_NIST_256_TOP,
 259         BN_NIST_256_TOP,
 260         0,
 261         BN_FLG_STATIC_DATA
 262         };
 263
 264 static const BIGNUM _bignum_nist_p_384 =
 265         {
 266         (BN_ULONG *)_nist_p_384[0],
 267         BN_NIST_384_TOP,
 268         BN_NIST_384_TOP,
 269         0,
 270         BN_FLG_STATIC_DATA
 271         };
 272
 273 static const BIGNUM _bignum_nist_p_521 =
 274         {
 275         (BN_ULONG *)_nist_p_521,
 276         BN_NIST_521_TOP,
 277         BN_NIST_521_TOP,
 278         0,
 279         BN_FLG_STATIC_DATA
 280         };
 281
 282
 283 const BIGNUM *BN_get0_nist_prime_192(void)
 284         {
 285         return &_bignum_nist_p_192;
 286         }
 287
 288 const BIGNUM *BN_get0_nist_prime_224(void)
 289         {
 290         return &_bignum_nist_p_224;
 291         }
 292
 293 const BIGNUM *BN_get0_nist_prime_256(void)
 294         {
 295         return &_bignum_nist_p_256;
 296         }
 297
 298 const BIGNUM *BN_get0_nist_prime_384(void)
 299         {
 300         return &_bignum_nist_p_384;
 301         }
 302
 303 const BIGNUM *BN_get0_nist_prime_521(void)
 304         {
 305         return &_bignum_nist_p_521;
 306         }
 307
 308
 309 static void nist_cp_bn_0(BN_ULONG *buf, BN_ULONG *a, int top, int max)
 310         {
 311         int i;
 312         BN_ULONG *_tmp1 = (buf), *_tmp2 = (a);
 313
 314 #ifdef BN_DEBUG
 315         OPENSSL_assert(top <= max);
 316 #endif
 317         for (i = (top); i != 0; i--)
 318                 *_tmp1++ = *_tmp2++;
 319         for (i = (max) - (top); i != 0; i--)
 320                 *_tmp1++ = (BN_ULONG) 0;
 321         }
 322
 323 static void nist_cp_bn(BN_ULONG *buf, BN_ULONG *a, int top)
 324         {
 325         int i;
 326         BN_ULONG *_tmp1 = (buf), *_tmp2 = (a);
 327         for (i = (top); i != 0; i--)
 328                 *_tmp1++ = *_tmp2++;
 329         }
 330
 331 #if BN_BITS2 == 64
 332 #define bn_cp_64(to, n, from, m)        (to)[n] = (m>=0)?((from)[m]):0;
 333 #define bn_64_set_0(to, n)              (to)[n] = (BN_ULONG)0;
 334 /*
 335  * two following macros are implemented under assumption that they
 336  * are called in a sequence with *ascending* n, i.e. as they are...
 337  */
 338 #define bn_cp_32_naked(to, n, from, m)  (((n)&1)?(to[(n)/2]|=((m)&1)?(from[(m)/2]&BN_MASK2h):(from[(m)/2]<<32))\
 339                                                 :(to[(n)/2] =((m)&1)?(from[(m)/2]>>32):(from[(m)/2]&BN_MASK2l)))
 340 #define bn_32_set_0(to, n)              (((n)&1)?(to[(n)/2]&=BN_MASK2l):(to[(n)/2]=0));
 341 #define bn_cp_32(to,n,from,m)           ((m)>=0)?bn_cp_32_naked(to,n,from,m):bn_32_set_0(to,n)
 342 # if defined(L_ENDIAN)
 343 #  if defined(__arch64__)
 344 #   define NIST_INT64 long
 345 #  else
 346 #   define NIST_INT64 long long
 347 #  endif
 348 # endif
 349 #else
 350 #define bn_cp_64(to, n, from, m) \
 351         { \
 352         bn_cp_32(to, (n)*2, from, (m)*2); \
 353         bn_cp_32(to, (n)*2+1, from, (m)*2+1); \
 354         }
 355 #define bn_64_set_0(to, n) \
 356         { \
 357         bn_32_set_0(to, (n)*2); \
 358         bn_32_set_0(to, (n)*2+1); \
 359         }
 360 #define bn_cp_32(to, n, from, m)        (to)[n] = (m>=0)?((from)[m]):0;
 361 #define bn_32_set_0(to, n)              (to)[n] = (BN_ULONG)0;
 362 # if defined(_WIN32) && !defined(__GNUC__)
 363 #  define NIST_INT64 __int64
 364 # else
 365 #  define NIST_INT64 long long
 366 # endif
 367 #endif /* BN_BITS2 != 64 */
 368
 369 #define nist_set_192(to, from, a1, a2, a3) \
 370         { \
 371         bn_cp_64(to, 0, from, (a3) - 3) \
 372         bn_cp_64(to, 1, from, (a2) - 3) \
 373         bn_cp_64(to, 2, from, (a1) - 3) \
 374         }
 375
 376 int BN_nist_mod_192(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 377         BN_CTX *ctx)
 378         {
 379         int      top = a->top, i;
 380         int      carry;
 381         register BN_ULONG *r_d, *a_d = a->d;
 382         union   {
 383                 BN_ULONG        bn[BN_NIST_192_TOP];
 384                 unsigned int    ui[BN_NIST_192_TOP*sizeof(BN_ULONG)/sizeof(unsigned int)];
 385                 } buf;
 386         BN_ULONG c_d[BN_NIST_192_TOP],
 387                 *res;
 388         PTR_SIZE_INT mask;
 389         static const BIGNUM _bignum_nist_p_192_sqr = {
 390                 (BN_ULONG *)_nist_p_192_sqr,
 391                 sizeof(_nist_p_192_sqr)/sizeof(_nist_p_192_sqr[0]),
 392                 sizeof(_nist_p_192_sqr)/sizeof(_nist_p_192_sqr[0]),
 393                 0,BN_FLG_STATIC_DATA };
 394
 395         field = &_bignum_nist_p_192; /* just to make sure */
 396
 397         if (BN_is_negative(a) || BN_ucmp(a,&_bignum_nist_p_192_sqr)>=0)
 398                 return BN_nnmod(r, a, field, ctx);
 399
 400         i = BN_ucmp(field, a);
 401         if (i == 0)
 402                 {
 403                 BN_zero(r);
 404                 return 1;
 405                 }
 406         else if (i > 0)
 407                 return (r == a) ? 1 : (BN_copy(r ,a) != NULL);
 408
 409         if (r != a)
 410                 {
 411                 if (!bn_wexpand(r, BN_NIST_192_TOP))
 412                         return 0;
 413                 r_d = r->d;
 414                 nist_cp_bn(r_d, a_d, BN_NIST_192_TOP);
 415                 }
 416         else
 417                 r_d = a_d;
 418
 419         nist_cp_bn_0(buf.bn, a_d + BN_NIST_192_TOP, top - BN_NIST_192_TOP, BN_NIST_192_TOP);
 420
 421 #if defined(NIST_INT64)
 422         {
 423         NIST_INT64              acc;    /* accumulator */
 424         unsigned int            *rp=(unsigned int *)r_d;
 425         const unsigned int      *bp=(const unsigned int *)buf.ui;
 426
 427         acc  = rp[0];   acc += bp[3*2-6];
 428                         acc += bp[5*2-6]; rp[0] = (unsigned int)acc; acc >>= 32;
 429
 430         acc += rp[1];   acc += bp[3*2-5];
 431                         acc += bp[5*2-5]; rp[1] = (unsigned int)acc; acc >>= 32;
 432
 433         acc += rp[2];   acc += bp[3*2-6];
 434                         acc += bp[4*2-6];
 435                         acc += bp[5*2-6]; rp[2] = (unsigned int)acc; acc >>= 32;
 436
 437         acc += rp[3];   acc += bp[3*2-5];
 438                         acc += bp[4*2-5];
 439                         acc += bp[5*2-5]; rp[3] = (unsigned int)acc; acc >>= 32;
 440
 441         acc += rp[4];   acc += bp[4*2-6];
 442                         acc += bp[5*2-6]; rp[4] = (unsigned int)acc; acc >>= 32;
 443
 444         acc += rp[5];   acc += bp[4*2-5];
 445                         acc += bp[5*2-5]; rp[5] = (unsigned int)acc;
 446
 447         carry = (int)(acc>>32);
 448         }
 449 #else
 450         {
 451         BN_ULONG t_d[BN_NIST_192_TOP];
 452
 453         nist_set_192(t_d, buf.bn, 0, 3, 3);
 454         carry = (int)bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP);
 455         nist_set_192(t_d, buf.bn, 4, 4, 0);
 456         carry += (int)bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP);
 457         nist_set_192(t_d, buf.bn, 5, 5, 5)
 458         carry += (int)bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP);
 459         }
 460 #endif
 461         if (carry > 0)
 462                 carry = (int)bn_sub_words(r_d,r_d,_nist_p_192[carry-1],BN_NIST_192_TOP);
 463         else
 464                 carry = 1;
 465
 466         /*
 467          * we need 'if (carry==0 || result>=modulus) result-=modulus;'
 468          * as comparison implies subtraction, we can write
 469          * 'tmp=result-modulus; if (!carry || !borrow) result=tmp;'
 470          * this is what happens below, but without explicit if:-) a.
 471          */
 472         mask  = 0-(PTR_SIZE_INT)bn_sub_words(c_d,r_d,_nist_p_192[0],BN_NIST_192_TOP);
 473         mask &= 0-(PTR_SIZE_INT)carry;
 474         res   = (BN_ULONG *)
 475          (((PTR_SIZE_INT)c_d&~mask) | ((PTR_SIZE_INT)r_d&mask));
 476         nist_cp_bn(r_d, res, BN_NIST_192_TOP);
 477         r->top = BN_NIST_192_TOP;
 478         bn_correct_top(r);
 479
 480         return 1;
 481         }
 482
 483 typedef BN_ULONG (*bn_addsub_f)(BN_ULONG *,const BN_ULONG *,const BN_ULONG *,int);
 484
 485 #define nist_set_224(to, from, a1, a2, a3, a4, a5, a6, a7) \
 486         { \
 487         bn_cp_32(to, 0, from, (a7) - 7) \
 488         bn_cp_32(to, 1, from, (a6) - 7) \
 489         bn_cp_32(to, 2, from, (a5) - 7) \
 490         bn_cp_32(to, 3, from, (a4) - 7) \
 491         bn_cp_32(to, 4, from, (a3) - 7) \
 492         bn_cp_32(to, 5, from, (a2) - 7) \
 493         bn_cp_32(to, 6, from, (a1) - 7) \
 494         }
 495
 496 int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 497         BN_CTX *ctx)
 498         {
 499         int     top = a->top, i;
 500         int     carry;
 501         BN_ULONG *r_d, *a_d = a->d;
 502         BN_ULONG buf[BN_NIST_224_TOP],
 503                  c_d[BN_NIST_224_TOP],
 504                 *res;
 505         PTR_SIZE_INT mask;
 506         union { bn_addsub_f f; PTR_SIZE_INT p; } u;
 507         static const BIGNUM _bignum_nist_p_224_sqr = {
 508                 (BN_ULONG *)_nist_p_224_sqr,
 509                 sizeof(_nist_p_224_sqr)/sizeof(_nist_p_224_sqr[0]),
 510                 sizeof(_nist_p_224_sqr)/sizeof(_nist_p_224_sqr[0]),
 511                 0,BN_FLG_STATIC_DATA };
 512
 513
 514         field = &_bignum_nist_p_224; /* just to make sure */
 515
 516         if (BN_is_negative(a) || BN_ucmp(a,&_bignum_nist_p_224_sqr)>=0)
 517                 return BN_nnmod(r, a, field, ctx);
 518
 519         i = BN_ucmp(field, a);
 520         if (i == 0)
 521                 {
 522                 BN_zero(r);
 523                 return 1;
 524                 }
 525         else if (i > 0)
 526                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
 527
 528         if (r != a)
 529                 {
 530                 if (!bn_wexpand(r, BN_NIST_224_TOP))
 531                         return 0;
 532                 r_d = r->d;
 533                 nist_cp_bn(r_d, a_d, BN_NIST_224_TOP);
 534                 }
 535         else
 536                 r_d = a_d;
 537
 538 #if BN_BITS2==64
 539         /* copy upper 256 bits of 448 bit number ... */
 540         nist_cp_bn_0(c_d, a_d + (BN_NIST_224_TOP-1), top - (BN_NIST_224_TOP-1), BN_NIST_224_TOP);
 541         /* ... and right shift by 32 to obtain upper 224 bits */
 542         nist_set_224(buf, c_d, 14, 13, 12, 11, 10, 9, 8);
 543         /* truncate lower part to 224 bits too */
 544         r_d[BN_NIST_224_TOP-1] &= BN_MASK2l;
 545 #else
 546         nist_cp_bn_0(buf, a_d + BN_NIST_224_TOP, top - BN_NIST_224_TOP, BN_NIST_224_TOP);
 547 #endif
 548
 549 #if defined(NIST_INT64) && BN_BITS2!=64
 550         {
 551         NIST_INT64              acc;    /* accumulator */
 552         unsigned int            *rp=(unsigned int *)r_d;
 553         const unsigned int      *bp=(const unsigned int *)buf;
 554
 555         acc  = rp[0];   acc -= bp[7-7];
 556                         acc -= bp[11-7]; rp[0] = (unsigned int)acc; acc >>= 32;
 557
 558         acc += rp[1];   acc -= bp[8-7];
 559                         acc -= bp[12-7]; rp[1] = (unsigned int)acc; acc >>= 32;
 560
 561         acc += rp[2];   acc -= bp[9-7];
 562                         acc -= bp[13-7]; rp[2] = (unsigned int)acc; acc >>= 32;
 563
 564         acc += rp[3];   acc += bp[7-7];
 565                         acc += bp[11-7];
 566                         acc -= bp[10-7]; rp[3] = (unsigned int)acc; acc>>= 32;
 567
 568         acc += rp[4];   acc += bp[8-7];
 569                         acc += bp[12-7];
 570                         acc -= bp[11-7]; rp[4] = (unsigned int)acc; acc >>= 32;
 571
 572         acc += rp[5];   acc += bp[9-7];
 573                         acc += bp[13-7];
 574                         acc -= bp[12-7]; rp[5] = (unsigned int)acc; acc >>= 32;
 575
 576         acc += rp[6];   acc += bp[10-7];
 577                         acc -= bp[13-7]; rp[6] = (unsigned int)acc;
 578
 579         carry = (int)(acc>>32);
 580 # if BN_BITS2==64
 581         rp[7] = carry;
 582 # endif
 583         }
 584 #else
 585         {
 586         BN_ULONG t_d[BN_NIST_224_TOP];
 587
 588         nist_set_224(t_d, buf, 10, 9, 8, 7, 0, 0, 0);
 589         carry = (int)bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP);
 590         nist_set_224(t_d, buf, 0, 13, 12, 11, 0, 0, 0);
 591         carry += (int)bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP);
 592         nist_set_224(t_d, buf, 13, 12, 11, 10, 9, 8, 7);
 593         carry -= (int)bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP);
 594         nist_set_224(t_d, buf, 0, 0, 0, 0, 13, 12, 11);
 595         carry -= (int)bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP);
 596
 597 #if BN_BITS2==64
 598         carry = (int)(r_d[BN_NIST_224_TOP-1]>>32);
 599 #endif
 600         }
 601 #endif
 602         u.f = bn_sub_words;
 603         if (carry > 0)
 604                 {
 605                 carry = (int)bn_sub_words(r_d,r_d,_nist_p_224[carry-1],BN_NIST_224_TOP);
 606 #if BN_BITS2==64
 607                 carry=(int)(~(r_d[BN_NIST_224_TOP-1]>>32))&1;
 608 #endif
 609                 }
 610         else if (carry < 0)
 611                 {
 612                 /* it's a bit more comlicated logic in this case.
 613                  * if bn_add_words yields no carry, then result
 614                  * has to be adjusted by unconditionally *adding*
 615                  * the modulus. but if it does, then result has
 616                  * to be compared to the modulus and conditionally
 617                  * adjusted by *subtracting* the latter. */
 618                 carry = (int)bn_add_words(r_d,r_d,_nist_p_224[-carry-1],BN_NIST_224_TOP);
 619                 mask = 0-(PTR_SIZE_INT)carry;
 620                 u.p = ((PTR_SIZE_INT)bn_sub_words&mask) |
 621                  ((PTR_SIZE_INT)bn_add_words&~mask);
 622                 }
 623         else
 624                 carry = 1;
 625
 626         /* otherwise it's effectively same as in BN_nist_mod_192... */
 627         mask  = 0-(PTR_SIZE_INT)(*u.f)(c_d,r_d,_nist_p_224[0],BN_NIST_224_TOP);
 628         mask &= 0-(PTR_SIZE_INT)carry;
 629         res   = (BN_ULONG *)(((PTR_SIZE_INT)c_d&~mask) |
 630          ((PTR_SIZE_INT)r_d&mask));
 631         nist_cp_bn(r_d, res, BN_NIST_224_TOP);
 632         r->top = BN_NIST_224_TOP;
 633         bn_correct_top(r);
 634
 635         return 1;
 636         }
 637
 638 #define nist_set_256(to, from, a1, a2, a3, a4, a5, a6, a7, a8) \
 639         { \
 640         bn_cp_32(to, 0, from, (a8) - 8) \
 641         bn_cp_32(to, 1, from, (a7) - 8) \
 642         bn_cp_32(to, 2, from, (a6) - 8) \
 643         bn_cp_32(to, 3, from, (a5) - 8) \
 644         bn_cp_32(to, 4, from, (a4) - 8) \
 645         bn_cp_32(to, 5, from, (a3) - 8) \
 646         bn_cp_32(to, 6, from, (a2) - 8) \
 647         bn_cp_32(to, 7, from, (a1) - 8) \
 648         }
 649
 650 int BN_nist_mod_256(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 651         BN_CTX *ctx)
 652         {
 653         int     i, top = a->top;
 654         int     carry = 0;
 655         register BN_ULONG *a_d = a->d, *r_d;
 656         union   {
 657                 BN_ULONG bn[BN_NIST_256_TOP];
 658                 unsigned int ui[BN_NIST_256_TOP*sizeof(BN_ULONG)/sizeof(unsigned int)];
 659                 } buf;
 660         BN_ULONG c_d[BN_NIST_256_TOP],
 661                 *res;
 662         PTR_SIZE_INT mask;
 663         union { bn_addsub_f f; PTR_SIZE_INT p; } u;
 664         static const BIGNUM _bignum_nist_p_256_sqr = {
 665                 (BN_ULONG *)_nist_p_256_sqr,
 666                 sizeof(_nist_p_256_sqr)/sizeof(_nist_p_256_sqr[0]),
 667                 sizeof(_nist_p_256_sqr)/sizeof(_nist_p_256_sqr[0]),
 668                 0,BN_FLG_STATIC_DATA };
 669
 670         field = &_bignum_nist_p_256; /* just to make sure */
 671
 672         if (BN_is_negative(a) || BN_ucmp(a,&_bignum_nist_p_256_sqr)>=0)
 673                 return BN_nnmod(r, a, field, ctx);
 674
 675         i = BN_ucmp(field, a);
 676         if (i == 0)
 677                 {
 678                 BN_zero(r);
 679                 return 1;
 680                 }
 681         else if (i > 0)
 682                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
 683
 684         if (r != a)
 685                 {
 686                 if (!bn_wexpand(r, BN_NIST_256_TOP))
 687                         return 0;
 688                 r_d = r->d;
 689                 nist_cp_bn(r_d, a_d, BN_NIST_256_TOP);
 690                 }
 691         else
 692                 r_d = a_d;
 693
 694         nist_cp_bn_0(buf.bn, a_d + BN_NIST_256_TOP, top - BN_NIST_256_TOP, BN_NIST_256_TOP);
 695
 696 #if defined(NIST_INT64)
 697         {
 698         NIST_INT64              acc;    /* accumulator */
 699         unsigned int            *rp=(unsigned int *)r_d;
 700         const unsigned int      *bp=(const unsigned int *)buf.ui;
 701
 702         acc = rp[0];    acc += bp[8-8];
 703                         acc += bp[9-8];
 704                         acc -= bp[11-8];
 705                         acc -= bp[12-8];
 706                         acc -= bp[13-8];
 707                         acc -= bp[14-8]; rp[0] = (unsigned int)acc; acc >>= 32;
 708
 709         acc += rp[1];   acc += bp[9-8];
 710                         acc += bp[10-8];
 711                         acc -= bp[12-8];
 712                         acc -= bp[13-8];
 713                         acc -= bp[14-8];
 714                         acc -= bp[15-8]; rp[1] = (unsigned int)acc; acc >>= 32;
 715
 716         acc += rp[2];   acc += bp[10-8];
 717                         acc += bp[11-8];
 718                         acc -= bp[13-8];
 719                         acc -= bp[14-8];
 720                         acc -= bp[15-8]; rp[2] = (unsigned int)acc; acc >>= 32;
 721
 722         acc += rp[3];   acc += bp[11-8];
 723                         acc += bp[11-8];
 724                         acc += bp[12-8];
 725                         acc += bp[12-8];
 726                         acc += bp[13-8];
 727                         acc -= bp[15-8];
 728                         acc -= bp[8-8];
 729                         acc -= bp[9-8];  rp[3] = (unsigned int)acc; acc >>= 32;
 730
 731         acc += rp[4];   acc += bp[12-8];
 732                         acc += bp[12-8];
 733                         acc += bp[13-8];
 734                         acc += bp[13-8];
 735                         acc += bp[14-8];
 736                         acc -= bp[9-8];
 737                         acc -= bp[10-8]; rp[4] = (unsigned int)acc; acc >>= 32;
 738
 739         acc += rp[5];   acc += bp[13-8];
 740                         acc += bp[13-8];
 741                         acc += bp[14-8];
 742                         acc += bp[14-8];
 743                         acc += bp[15-8];
 744                         acc -= bp[10-8];
 745                         acc -= bp[11-8]; rp[5] = (unsigned int)acc; acc >>= 32;
 746
 747         acc += rp[6];   acc += bp[14-8];
 748                         acc += bp[14-8];
 749                         acc += bp[15-8];
 750                         acc += bp[15-8];
 751                         acc += bp[14-8];
 752                         acc += bp[13-8];
 753                         acc -= bp[8-8];
 754                         acc -= bp[9-8];  rp[6] = (unsigned int)acc; acc >>= 32;
 755
 756         acc += rp[7];   acc += bp[15-8];
 757                         acc += bp[15-8];
 758                         acc += bp[15-8];
 759                         acc += bp[8 -8];
 760                         acc -= bp[10-8];
 761                         acc -= bp[11-8];
 762                         acc -= bp[12-8];
 763                         acc -= bp[13-8]; rp[7] = (unsigned int)acc;
 764
 765         carry = (int)(acc>>32);
 766         }
 767 #else
 768         {
 769         BN_ULONG t_d[BN_NIST_256_TOP];
 770
 771         /*S1*/
 772         nist_set_256(t_d, buf.bn, 15, 14, 13, 12, 11, 0, 0, 0);
 773         /*S2*/
 774         nist_set_256(c_d, buf.bn, 0, 15, 14, 13, 12, 0, 0, 0);
 775         carry = (int)bn_add_words(t_d, t_d, c_d, BN_NIST_256_TOP);
 776         /* left shift */
 777                 {
 778                 register BN_ULONG *ap,t,c;
 779                 ap = t_d;
 780                 c=0;
 781                 for (i = BN_NIST_256_TOP; i != 0; --i)
 782                         {
 783                         t= *ap;
 784                         *(ap++)=((t<<1)|c)&BN_MASK2;
 785                         c=(t & BN_TBIT)?1:0;
 786                         }
 787                 carry <<= 1;
 788                 carry  |= c;
 789                 }
 790         carry += (int)bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 791         /*S3*/
 792         nist_set_256(t_d, buf.bn, 15, 14, 0, 0, 0, 10, 9, 8);
 793         carry += (int)bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 794         /*S4*/
 795         nist_set_256(t_d, buf.bn, 8, 13, 15, 14, 13, 11, 10, 9);
 796         carry += (int)bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 797         /*D1*/
 798         nist_set_256(t_d, buf.bn, 10, 8, 0, 0, 0, 13, 12, 11);
 799         carry -= (int)bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 800         /*D2*/
 801         nist_set_256(t_d, buf.bn, 11, 9, 0, 0, 15, 14, 13, 12);
 802         carry -= (int)bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 803         /*D3*/
 804         nist_set_256(t_d, buf.bn, 12, 0, 10, 9, 8, 15, 14, 13);
 805         carry -= (int)bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 806         /*D4*/
 807         nist_set_256(t_d, buf.bn, 13, 0, 11, 10, 9, 0, 15, 14);
 808         carry -= (int)bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
 809
 810         }
 811 #endif
 812         /* see BN_nist_mod_224 for explanation */
 813         u.f = bn_sub_words;
 814         if (carry > 0)
 815                 carry = (int)bn_sub_words(r_d,r_d,_nist_p_256[carry-1],BN_NIST_256_TOP);
 816         else if (carry < 0)
 817                 {
 818                 carry = (int)bn_add_words(r_d,r_d,_nist_p_256[-carry-1],BN_NIST_256_TOP);
 819                 mask = 0-(PTR_SIZE_INT)carry;
 820                 u.p = ((PTR_SIZE_INT)bn_sub_words&mask) |
 821                  ((PTR_SIZE_INT)bn_add_words&~mask);
 822                 }
 823         else
 824                 carry = 1;
 825
 826         mask  = 0-(PTR_SIZE_INT)(*u.f)(c_d,r_d,_nist_p_256[0],BN_NIST_256_TOP);
 827         mask &= 0-(PTR_SIZE_INT)carry;
 828         res   = (BN_ULONG *)(((PTR_SIZE_INT)c_d&~mask) |
 829          ((PTR_SIZE_INT)r_d&mask));
 830         nist_cp_bn(r_d, res, BN_NIST_256_TOP);
 831         r->top = BN_NIST_256_TOP;
 832         bn_correct_top(r);
 833
 834         return 1;
 835         }
 836
 837 #define nist_set_384(to,from,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12) \
 838         { \
 839         bn_cp_32(to, 0, from,  (a12) - 12) \
 840         bn_cp_32(to, 1, from,  (a11) - 12) \
 841         bn_cp_32(to, 2, from,  (a10) - 12) \
 842         bn_cp_32(to, 3, from,  (a9) - 12)  \
 843         bn_cp_32(to, 4, from,  (a8) - 12)  \
 844         bn_cp_32(to, 5, from,  (a7) - 12)  \
 845         bn_cp_32(to, 6, from,  (a6) - 12)  \
 846         bn_cp_32(to, 7, from,  (a5) - 12)  \
 847         bn_cp_32(to, 8, from,  (a4) - 12)  \
 848         bn_cp_32(to, 9, from,  (a3) - 12)  \
 849         bn_cp_32(to, 10, from, (a2) - 12)  \
 850         bn_cp_32(to, 11, from, (a1) - 12)  \
 851         }
 852
 853 int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 854         BN_CTX *ctx)
 855         {
 856         int     i, top = a->top;
 857         int     carry = 0;
 858         register BN_ULONG *r_d, *a_d = a->d;
 859         union   {
 860                 BN_ULONG bn[BN_NIST_384_TOP];
 861                 unsigned int ui[BN_NIST_384_TOP*sizeof(BN_ULONG)/sizeof(unsigned int)];
 862                 } buf;
 863         BN_ULONG c_d[BN_NIST_384_TOP],
 864                 *res;
 865         PTR_SIZE_INT mask;
 866         union { bn_addsub_f f; PTR_SIZE_INT p; } u;
 867         static const BIGNUM _bignum_nist_p_384_sqr = {
 868                 (BN_ULONG *)_nist_p_384_sqr,
 869                 sizeof(_nist_p_384_sqr)/sizeof(_nist_p_384_sqr[0]),
 870                 sizeof(_nist_p_384_sqr)/sizeof(_nist_p_384_sqr[0]),
 871                 0,BN_FLG_STATIC_DATA };
 872
 873
 874         field = &_bignum_nist_p_384; /* just to make sure */
 875
 876         if (BN_is_negative(a) || BN_ucmp(a,&_bignum_nist_p_384_sqr)>=0)
 877                 return BN_nnmod(r, a, field, ctx);
 878
 879         i = BN_ucmp(field, a);
 880         if (i == 0)
 881                 {
 882                 BN_zero(r);
 883                 return 1;
 884                 }
 885         else if (i > 0)
 886                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
 887
 888         if (r != a)
 889                 {
 890                 if (!bn_wexpand(r, BN_NIST_384_TOP))
 891                         return 0;
 892                 r_d = r->d;
 893                 nist_cp_bn(r_d, a_d, BN_NIST_384_TOP);
 894                 }
 895         else
 896                 r_d = a_d;
 897
 898         nist_cp_bn_0(buf.bn, a_d + BN_NIST_384_TOP, top - BN_NIST_384_TOP, BN_NIST_384_TOP);
 899
 900 #if defined(NIST_INT64)
 901         {
 902         NIST_INT64              acc;    /* accumulator */
 903         unsigned int            *rp=(unsigned int *)r_d;
 904         const unsigned int      *bp=(const unsigned int *)buf.ui;
 905
 906         acc = rp[0];    acc += bp[12-12];
 907                         acc += bp[21-12];
 908                         acc += bp[20-12];
 909                         acc -= bp[23-12]; rp[0] = (unsigned int)acc; acc >>= 32;
 910
 911         acc += rp[1];   acc += bp[13-12];
 912                         acc += bp[22-12];
 913                         acc += bp[23-12];
 914                         acc -= bp[12-12];
 915                         acc -= bp[20-12]; rp[1] = (unsigned int)acc; acc >>= 32;
 916
 917         acc += rp[2];   acc += bp[14-12];
 918                         acc += bp[23-12];
 919                         acc -= bp[13-12];
 920                         acc -= bp[21-12]; rp[2] = (unsigned int)acc; acc >>= 32;
 921
 922         acc += rp[3];   acc += bp[15-12];
 923                         acc += bp[12-12];
 924                         acc += bp[20-12];
 925                         acc += bp[21-12];
 926                         acc -= bp[14-12];
 927                         acc -= bp[22-12];
 928                         acc -= bp[23-12]; rp[3] = (unsigned int)acc; acc >>= 32;
 929
 930         acc += rp[4];   acc += bp[21-12];
 931                         acc += bp[21-12];
 932                         acc += bp[16-12];
 933                         acc += bp[13-12];
 934                         acc += bp[12-12];
 935                         acc += bp[20-12];
 936                         acc += bp[22-12];
 937                         acc -= bp[15-12];
 938                         acc -= bp[23-12];
 939                         acc -= bp[23-12]; rp[4] = (unsigned int)acc; acc >>= 32;
 940
 941         acc += rp[5];   acc += bp[22-12];
 942                         acc += bp[22-12];
 943                         acc += bp[17-12];
 944                         acc += bp[14-12];
 945                         acc += bp[13-12];
 946                         acc += bp[21-12];
 947                         acc += bp[23-12];
 948                         acc -= bp[16-12]; rp[5] = (unsigned int)acc; acc >>= 32;
 949
 950         acc += rp[6];   acc += bp[23-12];
 951                         acc += bp[23-12];
 952                         acc += bp[18-12];
 953                         acc += bp[15-12];
 954                         acc += bp[14-12];
 955                         acc += bp[22-12];
 956                         acc -= bp[17-12]; rp[6] = (unsigned int)acc; acc >>= 32;
 957
 958         acc += rp[7];   acc += bp[19-12];
 959                         acc += bp[16-12];
 960                         acc += bp[15-12];
 961                         acc += bp[23-12];
 962                         acc -= bp[18-12]; rp[7] = (unsigned int)acc; acc >>= 32;
 963
 964         acc += rp[8];   acc += bp[20-12];
 965                         acc += bp[17-12];
 966                         acc += bp[16-12];
 967                         acc -= bp[19-12]; rp[8] = (unsigned int)acc; acc >>= 32;
 968
 969         acc += rp[9];   acc += bp[21-12];
 970                         acc += bp[18-12];
 971                         acc += bp[17-12];
 972                         acc -= bp[20-12]; rp[9] = (unsigned int)acc; acc >>= 32;
 973
 974         acc += rp[10];  acc += bp[22-12];
 975                         acc += bp[19-12];
 976                         acc += bp[18-12];
 977                         acc -= bp[21-12]; rp[10] = (unsigned int)acc; acc >>= 32;
 978
 979         acc += rp[11];  acc += bp[23-12];
 980                         acc += bp[20-12];
 981                         acc += bp[19-12];
 982                         acc -= bp[22-12]; rp[11] = (unsigned int)acc;
 983
 984         carry = (int)(acc>>32);
 985         }
 986 #else
 987         {
 988         BN_ULONG t_d[BN_NIST_384_TOP];
 989
 990         /*S1*/
 991         nist_set_256(t_d, buf.bn, 0, 0, 0, 0, 0, 23-4, 22-4, 21-4);
 992                 /* left shift */
 993                 {
 994                 register BN_ULONG *ap,t,c;
 995                 ap = t_d;
 996                 c=0;
 997                 for (i = 3; i != 0; --i)
 998                         {
 999                         t= *ap;
1000                         *(ap++)=((t<<1)|c)&BN_MASK2;
1001                         c=(t & BN_TBIT)?1:0;
1002                         }
1003                 *ap=c;
1004                 }
1005         carry = (int)bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2),
1006                 t_d, BN_NIST_256_TOP);
1007         /*S2 */
1008         carry += (int)bn_add_words(r_d, r_d, buf.bn, BN_NIST_384_TOP);
1009         /*S3*/
1010         nist_set_384(t_d,buf.bn,20,19,18,17,16,15,14,13,12,23,22,21);
1011         carry += (int)bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP);
1012         /*S4*/
1013         nist_set_384(t_d,buf.bn,19,18,17,16,15,14,13,12,20,0,23,0);
1014         carry += (int)bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP);
1015         /*S5*/
1016         nist_set_384(t_d, buf.bn,0,0,0,0,23,22,21,20,0,0,0,0);
1017         carry += (int)bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP);
1018         /*S6*/
1019         nist_set_384(t_d,buf.bn,0,0,0,0,0,0,23,22,21,0,0,20);
1020         carry += (int)bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP);
1021         /*D1*/
1022         nist_set_384(t_d,buf.bn,22,21,20,19,18,17,16,15,14,13,12,23);
1023         carry -= (int)bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP);
1024         /*D2*/
1025         nist_set_384(t_d,buf.bn,0,0,0,0,0,0,0,23,22,21,20,0);
1026         carry -= (int)bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP);
1027         /*D3*/
1028         nist_set_384(t_d,buf.bn,0,0,0,0,0,0,0,23,23,0,0,0);
1029         carry -= (int)bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP);
1030
1031         }
1032 #endif
1033         /* see BN_nist_mod_224 for explanation */
1034         u.f = bn_sub_words;
1035         if (carry > 0)
1036                 carry = (int)bn_sub_words(r_d,r_d,_nist_p_384[carry-1],BN_NIST_384_TOP);
1037         else if (carry < 0)
1038                 {
1039                 carry = (int)bn_add_words(r_d,r_d,_nist_p_384[-carry-1],BN_NIST_384_TOP);
1040                 mask = 0-(PTR_SIZE_INT)carry;
1041                 u.p = ((PTR_SIZE_INT)bn_sub_words&mask) |
1042                  ((PTR_SIZE_INT)bn_add_words&~mask);
1043                 }
1044         else
1045                 carry = 1;
1046
1047         mask  = 0-(PTR_SIZE_INT)(*u.f)(c_d,r_d,_nist_p_384[0],BN_NIST_384_TOP);
1048         mask &= 0-(PTR_SIZE_INT)carry;
1049         res   = (BN_ULONG *)(((PTR_SIZE_INT)c_d&~mask) |
1050          ((PTR_SIZE_INT)r_d&mask));
1051         nist_cp_bn(r_d, res, BN_NIST_384_TOP);
1052         r->top = BN_NIST_384_TOP;
1053         bn_correct_top(r);
1054
1055         return 1;
1056         }
1057
1058 #define BN_NIST_521_RSHIFT      (521%BN_BITS2)
1059 #define BN_NIST_521_LSHIFT      (BN_BITS2-BN_NIST_521_RSHIFT)
1060 #define BN_NIST_521_TOP_MASK    ((BN_ULONG)BN_MASK2>>BN_NIST_521_LSHIFT)
1061
1062 int BN_nist_mod_521(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
1063         BN_CTX *ctx)
1064         {
1065         int     top = a->top, i;
1066         BN_ULONG *r_d, *a_d = a->d,
1067                  t_d[BN_NIST_521_TOP],
1068                  val,tmp,*res;
1069         PTR_SIZE_INT mask;
1070         static const BIGNUM _bignum_nist_p_521_sqr = {
1071                 (BN_ULONG *)_nist_p_521_sqr,
1072                 sizeof(_nist_p_521_sqr)/sizeof(_nist_p_521_sqr[0]),
1073                 sizeof(_nist_p_521_sqr)/sizeof(_nist_p_521_sqr[0]),
1074                 0,BN_FLG_STATIC_DATA };
1075
1076         field = &_bignum_nist_p_521; /* just to make sure */
1077
1078         if (BN_is_negative(a) || BN_ucmp(a,&_bignum_nist_p_521_sqr)>=0)
1079                 return BN_nnmod(r, a, field, ctx);
1080
1081         i = BN_ucmp(field, a);
1082         if (i == 0)
1083                 {
1084                 BN_zero(r);
1085                 return 1;
1086                 }
1087         else if (i > 0)
1088                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
1089
1090         if (r != a)
1091                 {
1092                 if (!bn_wexpand(r,BN_NIST_521_TOP))
1093                         return 0;
1094                 r_d = r->d;
1095                 nist_cp_bn(r_d,a_d, BN_NIST_521_TOP);
1096                 }
1097         else
1098                 r_d = a_d;
1099
1100         /* upper 521 bits, copy ... */
1101         nist_cp_bn_0(t_d,a_d + (BN_NIST_521_TOP-1), top - (BN_NIST_521_TOP-1),BN_NIST_521_TOP);
1102         /* ... and right shift */
1103         for (val=t_d[0],i=0; i<BN_NIST_521_TOP-1; i++)
1104                 {
1105                 tmp = val>>BN_NIST_521_RSHIFT;
1106                 val = t_d[i+1];
1107                 t_d[i] = (tmp | val<<BN_NIST_521_LSHIFT) & BN_MASK2;
1108                 }
1109         t_d[i] = val>>BN_NIST_521_RSHIFT;
1110         /* lower 521 bits */
1111         r_d[i] &= BN_NIST_521_TOP_MASK;
1112
1113         bn_add_words(r_d,r_d,t_d,BN_NIST_521_TOP);
1114         mask = 0-(PTR_SIZE_INT)bn_sub_words(t_d,r_d,_nist_p_521,BN_NIST_521_TOP);
1115         res  = (BN_ULONG *)(((PTR_SIZE_INT)t_d&~mask) |
1116          ((PTR_SIZE_INT)r_d&mask));
1117         nist_cp_bn(r_d,res,BN_NIST_521_TOP);
1118         r->top = BN_NIST_521_TOP;
1119         bn_correct_top(r);
1120
1121         return 1;
1122         }
1123
1124 int (*BN_nist_mod_func(const BIGNUM *p))(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, BN_CTX *ctx)
1125         {
1126         if (BN_ucmp(&_bignum_nist_p_192, p) == 0)
1127                 return BN_nist_mod_192;
1128         if (BN_ucmp(&_bignum_nist_p_224, p) == 0)
1129                 return BN_nist_mod_224;
1130         if (BN_ucmp(&_bignum_nist_p_256, p) == 0)
1131                 return BN_nist_mod_256;
1132         if (BN_ucmp(&_bignum_nist_p_384, p) == 0)
1133                 return BN_nist_mod_384;
1134         if (BN_ucmp(&_bignum_nist_p_521, p) == 0)
1135                 return BN_nist_mod_521;
1136         return 0;
1137         }