diff options
Diffstat (limited to 'crypto/bn/bn_nist.c')
| -rw-r--r-- | crypto/bn/bn_nist.c | 653 |
1 files changed, 327 insertions, 326 deletions
diff --git a/crypto/bn/bn_nist.c b/crypto/bn/bn_nist.c index f8e306b..1fc94f5 100644 --- a/crypto/bn/bn_nist.c +++ b/crypto/bn/bn_nist.c @@ -59,6 +59,7 @@ #include "bn_lcl.h" #include "cryptlib.h" + #define BN_NIST_192_TOP (192+BN_BITS2-1)/BN_BITS2 #define BN_NIST_224_TOP (224+BN_BITS2-1)/BN_BITS2 #define BN_NIST_256_TOP (256+BN_BITS2-1)/BN_BITS2 @@ -99,114 +100,106 @@ static const BN_ULONG _nist_p_521[] = {0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF, 0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF, 0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF, 0xFFFFFFFF,0x000001FF}; -#elif BN_BITS2 == 16 -static const BN_ULONG _nist_p_192[] = {0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFE, - 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF}; -static const BN_ULONG _nist_p_224[] = {0x0001,0x0000,0x0000,0x0000,0x0000, - 0x0000,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF}; -static const BN_ULONG _nist_p_256[] = {0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF, - 0xFFFF,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0001,0x0000,0xFFFF, - 0xFFFF}; -static const BN_ULONG _nist_p_384[] = {0xFFFF,0xFFFF,0x0000,0x0000,0x0000, - 0x0000,0xFFFF,0xFFFF,0xFFFE,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF, - 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF}; -static const BN_ULONG _nist_p_521[] = {0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF, - 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF, - 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF, - 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0x01FF}; -#elif BN_BITS2 == 8 -static const BN_ULONG _nist_p_192[] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFE,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFF,0xFF}; -static const BN_ULONG _nist_p_224[] = {0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00, - 0x00,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF}; -static const BN_ULONG _nist_p_256[] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, - 0x00,0x00,0x01,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF}; -static const BN_ULONG _nist_p_384[] = {0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00, - 0x00,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF,0xFE,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF}; -static const BN_ULONG _nist_p_521[] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, - 0xFF,0x01}; #endif + +static const BIGNUM _bignum_nist_p_192 = + { + (BN_ULONG *)_nist_p_192, + BN_NIST_192_TOP, + BN_NIST_192_TOP, + 0, + BN_FLG_STATIC_DATA + }; + +static const BIGNUM _bignum_nist_p_224 = + { + (BN_ULONG *)_nist_p_224, + BN_NIST_224_TOP, + BN_NIST_224_TOP, + 0, + BN_FLG_STATIC_DATA + }; + +static const BIGNUM _bignum_nist_p_256 = + { + (BN_ULONG *)_nist_p_256, + BN_NIST_256_TOP, + BN_NIST_256_TOP, + 0, + BN_FLG_STATIC_DATA + }; + +static const BIGNUM _bignum_nist_p_384 = + { + (BN_ULONG *)_nist_p_384, + BN_NIST_384_TOP, + BN_NIST_384_TOP, + 0, + BN_FLG_STATIC_DATA + }; + +static const BIGNUM _bignum_nist_p_521 = + { + (BN_ULONG *)_nist_p_521, + BN_NIST_521_TOP, + BN_NIST_521_TOP, + 0, + BN_FLG_STATIC_DATA + }; + + const BIGNUM *BN_get0_nist_prime_192(void) { - static BIGNUM const_nist_192 = { (BN_ULONG *)_nist_p_192, - BN_NIST_192_TOP, BN_NIST_192_TOP, 0, BN_FLG_STATIC_DATA }; - return &const_nist_192; + return &_bignum_nist_p_192; } const BIGNUM *BN_get0_nist_prime_224(void) { - static BIGNUM const_nist_224 = { (BN_ULONG *)_nist_p_224, - BN_NIST_224_TOP, BN_NIST_224_TOP, 0, BN_FLG_STATIC_DATA }; - return &const_nist_224; + return &_bignum_nist_p_224; } const BIGNUM *BN_get0_nist_prime_256(void) { - static BIGNUM const_nist_256 = { (BN_ULONG *)_nist_p_256, - BN_NIST_256_TOP, BN_NIST_256_TOP, 0, BN_FLG_STATIC_DATA }; - return &const_nist_256; + return &_bignum_nist_p_256; } const BIGNUM *BN_get0_nist_prime_384(void) { - static BIGNUM const_nist_384 = { (BN_ULONG *)_nist_p_384, - BN_NIST_384_TOP, BN_NIST_384_TOP, 0, BN_FLG_STATIC_DATA }; - return &const_nist_384; + return &_bignum_nist_p_384; } const BIGNUM *BN_get0_nist_prime_521(void) { - static BIGNUM const_nist_521 = { (BN_ULONG *)_nist_p_521, - BN_NIST_521_TOP, BN_NIST_521_TOP, 0, BN_FLG_STATIC_DATA }; - return &const_nist_521; + return &_bignum_nist_p_521; } -/* some misc internal functions */ -#if BN_BITS2 != 64 -static BN_ULONG _256_data[BN_NIST_256_TOP*6]; -static int _is_set_256_data = 0; -static void _init_256_data(void); - -static BN_ULONG _384_data[BN_NIST_384_TOP*8]; -static int _is_set_384_data = 0; -static void _init_384_data(void); -#endif - -#define BN_NIST_ADD_ONE(a) while (!(++(*(a)))) ++(a); static void nist_cp_bn_0(BN_ULONG *buf, BN_ULONG *a, int top, int max) - { + { int i; - BN_ULONG *_tmp1 = (buf), *_tmp2 = (a); - for (i = (top); i != 0; i--) - *_tmp1++ = *_tmp2++; - for (i = (max) - (top); i != 0; i--) - *_tmp1++ = (BN_ULONG) 0; - } + BN_ULONG *_tmp1 = (buf), *_tmp2 = (a); + + OPENSSL_assert(top <= max); + for (i = (top); i != 0; i--) + *_tmp1++ = *_tmp2++; + for (i = (max) - (top); i != 0; i--) + *_tmp1++ = (BN_ULONG) 0; + } static void nist_cp_bn(BN_ULONG *buf, BN_ULONG *a, int top) - { + { int i; - BN_ULONG *_tmp1 = (buf), *_tmp2 = (a); - for (i = (top); i != 0; i--) - *_tmp1++ = *_tmp2++; - } + BN_ULONG *_tmp1 = (buf), *_tmp2 = (a); + for (i = (top); i != 0; i--) + *_tmp1++ = *_tmp2++; + } #if BN_BITS2 == 64 -#define bn_cp_64(to, n, from, m) (to)[n] = (from)[m]; +#define bn_cp_64(to, n, from, m) (to)[n] = (m>=0)?((from)[m]):0; #define bn_64_set_0(to, n) (to)[n] = (BN_ULONG)0; /* TBD */ -#define bn_cp_32(to, n, from, m) (to)[n] = (from)[m]; +#define bn_cp_32(to, n, from, m) (to)[n] = (m>=0)?((from)[m]):0; #define bn_32_set_0(to, n) (to)[n] = (BN_ULONG)0; #else #define bn_cp_64(to, n, from, m) \ @@ -220,26 +213,8 @@ static void nist_cp_bn(BN_ULONG *buf, BN_ULONG *a, int top) bn_32_set_0(to, (n)*2+1); \ } #if BN_BITS2 == 32 -#define bn_cp_32(to, n, from, m) (to)[n] = (from)[m]; +#define bn_cp_32(to, n, from, m) (to)[n] = (m>=0)?((from)[m]):0; #define bn_32_set_0(to, n) (to)[n] = (BN_ULONG)0; -#elif BN_BITS2 == 16 -#define bn_cp_32(to, n, from, m) \ - { \ - (to)[(n)*2] = (from)[(m)*2]; \ - (to)[(n)*2+1] = (from)[(m)*2+1];\ - } -#define bn_32_set_0(to, n) { (to)[(n)*2] = 0; (to)[(n)*2+1] = 0; } -#elif BN_BITS2 == 8 -#define bn_cp_32(to, n, from, m) \ - { \ - (to)[(n)*4] = (from)[(m)*4]; \ - (to)[(n)*4+1] = (from)[(m)*4+1];\ - (to)[(n)*4+2] = (from)[(m)*4+2];\ - (to)[(n)*4+3] = (from)[(m)*4+3];\ - } -#define bn_32_set_0(to, n) \ - { (to)[(n)*4] = (BN_ULONG)0; (to)[(n)*4+1] = (BN_ULONG)0; \ - (to)[(n)*4+2] = (BN_ULONG)0; (to)[(n)*4+3] = (BN_ULONG)0; } #endif #endif /* BN_BITS2 != 64 */ @@ -255,10 +230,18 @@ int BN_nist_mod_192(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, BN_CTX *ctx) { int top = a->top, i; - BN_ULONG carry = 0; + int carry; register BN_ULONG *r_d, *a_d = a->d; BN_ULONG t_d[BN_NIST_192_TOP], - buf[BN_NIST_192_TOP]; + buf[BN_NIST_192_TOP], + c_d[BN_NIST_192_TOP], + *res; + size_t mask; + + field = &_bignum_nist_p_192; /* just to make sure */ + + if (BN_is_negative(a) || a->top > 2*BN_NIST_192_TOP) + return BN_nnmod(r, field, a, ctx); i = BN_ucmp(field, a); if (i == 0) @@ -269,9 +252,6 @@ int BN_nist_mod_192(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, else if (i > 0) return (r == a) ? 1 : (BN_copy(r ,a) != NULL); - if (top == BN_NIST_192_TOP) - return BN_usub(r, a, field); - if (r != a) { if (!bn_wexpand(r, BN_NIST_192_TOP)) @@ -284,41 +264,33 @@ int BN_nist_mod_192(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, nist_cp_bn_0(buf, a_d + BN_NIST_192_TOP, top - BN_NIST_192_TOP, BN_NIST_192_TOP); -#if defined(OPENSSL_SYS_VMS) && defined(__DECC) -# pragma message save -# pragma message disable BADSUBSCRIPT -#endif - nist_set_192(t_d, buf, 0, 3, 3); - if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP)) - ++carry; - + carry = bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_192,BN_NIST_192_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + nist_set_192(t_d, buf, 4, 4, 0); - if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP)) - ++carry; - -#if defined(OPENSSL_SYS_VMS) && defined(__DECC) -# pragma message restore -#endif + carry = bn_add_words(r_d, res, t_d, BN_NIST_192_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_192,BN_NIST_192_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); nist_set_192(t_d, buf, 5, 5, 5) - if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP)) - ++carry; + carry = bn_add_words(r_d, res, t_d, BN_NIST_192_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_192,BN_NIST_192_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); - while (carry) - { - if (bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP)) - --carry; - } + nist_cp_bn(r_d, res, BN_NIST_192_TOP); r->top = BN_NIST_192_TOP; bn_correct_top(r); - if (BN_ucmp(r, field) >= 0) + + if (BN_ucmp(field, r) <= 0) { - bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP); - bn_correct_top(r); + if (!BN_usub(r, r, field)) return 0; } - bn_check_top(r); return 1; } @@ -336,12 +308,20 @@ int BN_nist_mod_192(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, BN_CTX *ctx) { -#if BN_BITS2 != 64 +#if BN_BITS2 == 32 int top = a->top, i; - int carry = 0; + int carry; BN_ULONG *r_d, *a_d = a->d; BN_ULONG t_d[BN_NIST_224_TOP], - buf[BN_NIST_224_TOP]; + buf[BN_NIST_224_TOP], + c_d[BN_NIST_224_TOP], + *res; + size_t mask; + + field = &_bignum_nist_p_224; /* just to make sure */ + + if (BN_is_negative(a) || a->top > 2*BN_NIST_224_TOP) + return BN_nnmod(r, field, a, ctx); i = BN_ucmp(field, a); if (i == 0) @@ -352,9 +332,6 @@ int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, else if (i > 0) return (r == a)? 1 : (BN_copy(r ,a) != NULL); - if (top == BN_NIST_224_TOP) - return BN_usub(r, a, field); - if (r != a) { if (!bn_wexpand(r, BN_NIST_224_TOP)) @@ -368,65 +345,53 @@ int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, nist_cp_bn_0(buf, a_d + BN_NIST_224_TOP, top - BN_NIST_224_TOP, BN_NIST_224_TOP); nist_set_224(t_d, buf, 10, 9, 8, 7, 0, 0, 0); - if (bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP)) - ++carry; + carry = bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_224,BN_NIST_224_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + nist_set_224(t_d, buf, 0, 13, 12, 11, 0, 0, 0); - if (bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP)) - ++carry; + carry = bn_add_words(r_d, res, t_d, BN_NIST_224_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_224,BN_NIST_224_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + nist_set_224(t_d, buf, 13, 12, 11, 10, 9, 8, 7); - if (bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP)) - --carry; +#if BRANCH_FREE + carry = bn_sub_words(r_d, res, t_d, BN_NIST_224_TOP); + bn_add_words(c_d,r_d,_nist_p_224,BN_NIST_224_TOP); + mask = 0-(size_t)carry; + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); +#else + if (bn_sub_words(r_d, res, t_d, BN_NIST_224_TOP)) + bn_add_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP); +#endif nist_set_224(t_d, buf, 0, 0, 0, 0, 13, 12, 11); - if (bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP)) - --carry; - - if (carry > 0) - while (carry) - { - if (bn_sub_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP)) - --carry; - } - else if (carry < 0) - while (carry) - { - if (bn_add_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP)) - ++carry; - } +#if BRANCH_FREE + carry = bn_sub_words(r_d, res, t_d, BN_NIST_224_TOP); + bn_add_words(c_d,r_d,_nist_p_224,BN_NIST_224_TOP); + mask = 0-(size_t)carry; + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + nist_cp_bn(r_d, res, BN_NIST_224_TOP); +#else + if (bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP)) + bn_add_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP); +#endif r->top = BN_NIST_224_TOP; bn_correct_top(r); - if (BN_ucmp(r, field) >= 0) + + if (BN_ucmp(field, r) <= 0) { - bn_sub_words(r_d, r_d, _nist_p_224, BN_NIST_224_TOP); - bn_correct_top(r); + if (!BN_usub(r, r, field)) return 0; } - bn_check_top(r); + return 1; -#else +#else /* BN_BITS!=32 */ return 0; #endif } -#if BN_BITS2 != 64 -static void _init_256_data(void) - { - int i; - BN_ULONG *tmp1 = _256_data; - const BN_ULONG *tmp2 = tmp1; - - memcpy(tmp1, _nist_p_256, BN_NIST_256_TOP * sizeof(BN_ULONG)); - tmp1 += BN_NIST_256_TOP; - - for (i=0; i<5; i++) - { - bn_add_words(tmp1, _nist_p_256, tmp2, BN_NIST_256_TOP); - tmp2 = tmp1; - tmp1 += BN_NIST_256_TOP; - } - _is_set_256_data = 1; - } -#endif - #define nist_set_256(to, from, a1, a2, a3, a4, a5, a6, a7, a8) \ { \ if (a8 != 0) bn_cp_32(to, 0, from, (a8) - 8) else bn_32_set_0(to, 0)\ @@ -442,24 +407,21 @@ static void _init_256_data(void) int BN_nist_mod_256(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, BN_CTX *ctx) { -#if BN_BITS2 != 64 +#if BN_BITS2 == 32 int i, top = a->top; int carry = 0; register BN_ULONG *a_d = a->d, *r_d; BN_ULONG t_d[BN_NIST_256_TOP], - t_d2[BN_NIST_256_TOP], - buf[BN_NIST_256_TOP]; + buf[BN_NIST_256_TOP], + c_d[BN_NIST_256_TOP], + *res; + size_t mask; + + field = &_bignum_nist_p_256; /* just to make sure */ + + if (BN_is_negative(a) || a->top > 2*BN_NIST_256_TOP) + return BN_nnmod(r, field, a, ctx); - if (!_is_set_256_data) - { - CRYPTO_w_lock(CRYPTO_LOCK_BN); - - if (!_is_set_256_data) - _init_256_data(); - - CRYPTO_w_unlock(CRYPTO_LOCK_BN); - } - i = BN_ucmp(field, a); if (i == 0) { @@ -469,9 +431,6 @@ int BN_nist_mod_256(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, else if (i > 0) return (r == a)? 1 : (BN_copy(r ,a) != NULL); - if (top == BN_NIST_256_TOP) - return BN_usub(r, a, field); - if (r != a) { if (!bn_wexpand(r, BN_NIST_256_TOP)) @@ -487,98 +446,96 @@ int BN_nist_mod_256(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, /*S1*/ nist_set_256(t_d, buf, 15, 14, 13, 12, 11, 0, 0, 0); /*S2*/ - nist_set_256(t_d2,buf, 0, 15, 14, 13, 12, 0, 0, 0); - if (bn_add_words(t_d, t_d, t_d2, BN_NIST_256_TOP)) - carry = 2; - /* left shift */ - { - register BN_ULONG *ap,t,c; - ap = t_d; - c=0; - for (i = BN_NIST_256_TOP; i != 0; --i) - { - t= *ap; - *(ap++)=((t<<1)|c)&BN_MASK2; - c=(t & BN_TBIT)?1:0; - } - if (c) - ++carry; - } + nist_set_256(c_d,buf, 0, 15, 14, 13, 12, 0, 0, 0); + carry = bn_add_words(t_d, t_d, c_d, BN_NIST_256_TOP); + mask = 0-(size_t)bn_sub_words(c_d,t_d,_nist_p_256,BN_NIST_256_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)t_d&~mask)); + + carry = bn_add_words(t_d, res, res, BN_NIST_256_TOP); + mask = 0-(size_t)bn_sub_words(c_d,t_d,_nist_p_256,BN_NIST_256_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)t_d&~mask)); + + carry = bn_add_words(r_d, r_d, res, BN_NIST_256_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); - if (bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP)) - ++carry; /*S3*/ nist_set_256(t_d, buf, 15, 14, 0, 0, 0, 10, 9, 8); - if (bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP)) - ++carry; + carry = bn_add_words(r_d, res, t_d, BN_NIST_256_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + /*S4*/ nist_set_256(t_d, buf, 8, 13, 15, 14, 13, 11, 10, 9); - if (bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP)) - ++carry; + carry = bn_add_words(r_d, res, t_d, BN_NIST_256_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + /*D1*/ nist_set_256(t_d, buf, 10, 8, 0, 0, 0, 13, 12, 11); - if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP)) - --carry; +#if BRANCH_FREE + carry = bn_sub_words(r_d, res, t_d, BN_NIST_256_TOP); + bn_add_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP); + mask = 0-(size_t)carry; + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); +#else + if (bn_sub_words(r_d, res, t_d, BN_NIST_256_TOP)) + bn_add_words(r_d,r_d,_nist_p_256,BN_NIST_256_TOP); +#endif /*D2*/ nist_set_256(t_d, buf, 11, 9, 0, 0, 15, 14, 13, 12); +#if BRANCH_FREE + carry = bn_sub_words(r_d, res, t_d, BN_NIST_256_TOP); + bn_add_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP); + mask = 0-(size_t)carry; + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); +#else if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP)) - --carry; + bn_add_words(r_d,r_d,_nist_p_256,BN_NIST_256_TOP); +#endif /*D3*/ nist_set_256(t_d, buf, 12, 0, 10, 9, 8, 15, 14, 13); +#if BRANCH_FREE + carry = bn_sub_words(r_d, res, t_d, BN_NIST_256_TOP); + bn_add_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP); + mask = 0-(size_t)carry; + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); +#else if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP)) - --carry; + bn_add_words(r_d,r_d,_nist_p_256,BN_NIST_256_TOP); +#endif /*D4*/ nist_set_256(t_d, buf, 13, 0, 11, 10, 9, 0, 15, 14); - if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP)) - --carry; - - if (carry) - { - if (carry > 0) - bn_sub_words(r_d, r_d, _256_data + BN_NIST_256_TOP * - --carry, BN_NIST_256_TOP); - else - { - carry = -carry; - bn_add_words(r_d, r_d, _256_data + BN_NIST_256_TOP * - --carry, BN_NIST_256_TOP); - } - } +#if BRANCH_FREE + carry = bn_sub_words(r_d, res, t_d, BN_NIST_256_TOP); + bn_add_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP); + mask = 0-(size_t)carry; + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + nist_cp_bn(r_d, res, BN_NIST_384_TOP); +#else + if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP)) + bn_add_words(r_d,r_d,_nist_p_256,BN_NIST_256_TOP); +#endif r->top = BN_NIST_256_TOP; bn_correct_top(r); - if (BN_ucmp(r, field) >= 0) + + if (BN_ucmp(field, r) <= 0) { - bn_sub_words(r_d, r_d, _nist_p_256, BN_NIST_256_TOP); - bn_correct_top(r); + if (!BN_usub(r, r, field)) return 0; } - bn_check_top(r); + return 1; -#else +#else /* BN_BITS!=32 */ return 0; #endif } -#if BN_BITS2 != 64 -static void _init_384_data(void) - { - int i; - BN_ULONG *tmp1 = _384_data; - const BN_ULONG *tmp2 = tmp1; - - memcpy(tmp1, _nist_p_384, BN_NIST_384_TOP * sizeof(BN_ULONG)); - tmp1 += BN_NIST_384_TOP; - - for (i=0; i<7; i++) - { - bn_add_words(tmp1, _nist_p_384, tmp2, BN_NIST_384_TOP); - tmp2 = tmp1; - tmp1 += BN_NIST_384_TOP; - } - _is_set_384_data = 1; - } -#endif - #define nist_set_384(to,from,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12) \ { \ if (a12 != 0) bn_cp_32(to, 0, from, (a12) - 12) else bn_32_set_0(to, 0)\ @@ -598,22 +555,20 @@ static void _init_384_data(void) int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, BN_CTX *ctx) { -#if BN_BITS2 != 64 +#if BN_BITS2 == 32 int i, top = a->top; int carry = 0; register BN_ULONG *r_d, *a_d = a->d; BN_ULONG t_d[BN_NIST_384_TOP], - buf[BN_NIST_384_TOP]; + buf[BN_NIST_384_TOP], + c_d[BN_NIST_384_TOP], + *res; + size_t mask; - if (!_is_set_384_data) - { - CRYPTO_w_lock(CRYPTO_LOCK_BN); - - if (!_is_set_384_data) - _init_384_data(); + field = &_bignum_nist_p_384; /* just to make sure */ - CRYPTO_w_unlock(CRYPTO_LOCK_BN); - } + if (BN_is_negative(a) || a->top > 2*BN_NIST_384_TOP) + return BN_nnmod(r, field, a, ctx); i = BN_ucmp(field, a); if (i == 0) @@ -624,9 +579,6 @@ int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, else if (i > 0) return (r == a)? 1 : (BN_copy(r ,a) != NULL); - if (top == BN_NIST_384_TOP) - return BN_usub(r, a, field); - if (r != a) { if (!bn_wexpand(r, BN_NIST_384_TOP)) @@ -646,72 +598,108 @@ int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, register BN_ULONG *ap,t,c; ap = t_d; c=0; - for (i = BN_NIST_256_TOP; i != 0; --i) + for (i = 3; i != 0; --i) { t= *ap; *(ap++)=((t<<1)|c)&BN_MASK2; c=(t & BN_TBIT)?1:0; } + *ap=c; } - if (bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2), - t_d, BN_NIST_256_TOP)) - ++carry; + carry = bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2), + t_d, BN_NIST_256_TOP); + /* + * we need if (result>=modulus) subtract(result,modulus); + * in n-bit space this can be expressed as + * if (carry || result>=modulus) subtract(result,modulus); + * the catch is that comparison implies subtraction and + * therefore one can write tmp=subtract(result,modulus); + * and then if(carry || !borrow) result=tmp; this's what + * happens below, but without explicit if:-) a. + */ + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + /*S2 */ - if (bn_add_words(r_d, r_d, buf, BN_NIST_384_TOP)) - ++carry; + carry = bn_add_words(r_d, res, buf, BN_NIST_384_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + /*S3*/ nist_set_384(t_d,buf,20,19,18,17,16,15,14,13,12,23,22,21); - if (bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP)) - ++carry; + carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + /*S4*/ nist_set_384(t_d,buf,19,18,17,16,15,14,13,12,20,0,23,0); - if (bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP)) - ++carry; + carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + /*S5*/ - nist_set_256(t_d, buf, 0, 0, 0, 0, 23-4, 22-4, 21-4, 20-4); - if (bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2), - t_d, BN_NIST_256_TOP)) - ++carry; + nist_set_384(t_d, buf,0,0,0,0,23,22,21,20,0,0,0,0); + carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + /*S6*/ nist_set_384(t_d,buf,0,0,0,0,0,0,23,22,21,0,0,20); - if (bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP)) - ++carry; + carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP); + mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP); + mask = ~mask | (0-(size_t)carry); + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + /*D1*/ nist_set_384(t_d,buf,22,21,20,19,18,17,16,15,14,13,12,23); - if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP)) - --carry; +#if BRANCH_FREE + carry = bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP); + bn_add_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP); + mask = 0-(size_t)carry; + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); +#else + if (bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP)) + bn_add_words(r_d,r_d,_nist_p_384,BN_NIST_384_TOP); +#endif /*D2*/ nist_set_384(t_d,buf,0,0,0,0,0,0,0,23,22,21,20,0); +#if BRANCH_FREE + carry = bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP); + bn_add_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP); + mask = 0-(size_t)carry; + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); +#else if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP)) - --carry; + bn_add_words(r_d,r_d,_nist_p_384,BN_NIST_384_TOP); +#endif /*D3*/ nist_set_384(t_d,buf,0,0,0,0,0,0,0,23,23,0,0,0); - if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP)) - --carry; - - if (carry) - { - if (carry > 0) - bn_sub_words(r_d, r_d, _384_data + BN_NIST_384_TOP * - --carry, BN_NIST_384_TOP); - else - { - carry = -carry; - bn_add_words(r_d, r_d, _384_data + BN_NIST_384_TOP * - --carry, BN_NIST_384_TOP); - } - } +#if BRANCH_FREE + carry = bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP); + bn_add_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP); + mask = 0-(size_t)carry; + res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask)); + nist_cp_bn(r_d, res, BN_NIST_384_TOP); +#else + if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP)) + bn_add_words(r_d,r_d,_nist_p_384,BN_NIST_384_TOP); +#endif r->top = BN_NIST_384_TOP; bn_correct_top(r); - if (BN_ucmp(r, field) >= 0) + + if (BN_ucmp(field, r) <= 0) { - bn_sub_words(r_d, r_d, _nist_p_384, BN_NIST_384_TOP); - bn_correct_top(r); + if (!BN_usub(r, r, field)) return 0; } - bn_check_top(r); + return 1; -#else +#else /* BN_BITS!=32 */ return 0; #endif } @@ -723,20 +711,37 @@ int BN_nist_mod_521(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, #define BN_NIST_521_TOP_MASK (BN_ULONG)0x1FF #elif BN_BITS2 == 32 #define BN_NIST_521_TOP_MASK (BN_ULONG)0x1FF -#elif BN_BITS2 == 16 -#define BN_NIST_521_TOP_MASK (BN_ULONG)0x1FF -#elif BN_BITS2 == 8 -#define BN_NIST_521_TOP_MASK (BN_ULONG)0x1 #endif int top, ret = 0; - BN_ULONG *r_d; BIGNUM *tmp; + field = &_bignum_nist_p_521; /* just to make sure */ + + if (BN_is_negative(a)) + return BN_nnmod(r, field, a, ctx); + /* check whether a reduction is necessary */ top = a->top; if (top < BN_NIST_521_TOP || ( top == BN_NIST_521_TOP && - (!(a->d[BN_NIST_521_TOP-1] & ~(BN_NIST_521_TOP_MASK))))) - return (r == a)? 1 : (BN_copy(r ,a) != NULL); + (!(a->d[BN_NIST_521_TOP-1] & ~(BN_NIST_521_TOP_MASK))))) + { + int i = BN_ucmp(field, a); + if (i == 0) + { + BN_zero(r); + return 1; + } + else + { +#ifdef BN_DEBUG + OPENSSL_assert(i > 0); /* because 'field' is 1111...1111 */ +#endif + return (r == a)? 1 : (BN_copy(r ,a) != NULL); + } + } + + if (BN_num_bits(a) > 2*521) + return BN_nnmod(r, field, a, ctx); BN_CTX_start(ctx); tmp = BN_CTX_get(ctx); @@ -756,15 +761,11 @@ int BN_nist_mod_521(BIGNUM *r, const BIGNUM *a, const BIGNUM *field, if (!BN_uadd(r, tmp, r)) goto err; - top = r->top; - r_d = r->d; - if (top == BN_NIST_521_TOP && - (r_d[BN_NIST_521_TOP-1] & ~(BN_NIST_521_TOP_MASK))) + + if (BN_ucmp(field, r) <= 0) { - BN_NIST_ADD_ONE(r_d) - r_d[BN_NIST_521_TOP-1] &= BN_NIST_521_TOP_MASK; + if (!BN_usub(r, r, field)) goto err; } - bn_correct_top(r); ret = 1; err: |
