generic-library/openssl
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Do BN_nist_mod_384 by the book, as cheating doesn't work. Other functions

Browse Source 
will be revised too.
PR: 1593
This commit is contained in:
Andy Polyakov 2008-04-09 11:36:04 +00:00
parent 86173db853
commit 2c4226c42b
1 changed files with 63 additions and 59 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

122
crypto/bn/bn_nist.c
View File

@ -176,10 +176,6 @@ const BIGNUM *BN_get0_nist_prime_521(void)
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)+1)&BN_MASK2)) ++(a);
@ -527,26 +523,6 @@ int BN_nist_mod_256(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
#endif
}
#if BN_BITS2 == 32
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)\
@ -571,17 +547,10 @@ int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
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];
if (!_is_set_384_data)
{
CRYPTO_w_lock(CRYPTO_LOCK_BN);
if (!_is_set_384_data)
_init_384_data();
CRYPTO_w_unlock(CRYPTO_LOCK_BN);
}
buf[BN_NIST_384_TOP],
c_d[BN_NIST_384_TOP],
*res;
size_t mask;
i = BN_ucmp(field, a);
if (i == 0)
@ -624,48 +593,83 @@ int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
}
carry = bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2),
t_d, BN_NIST_256_TOP);
/* this is equivalent to if (result >= module) */
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 */
carry += bn_add_words(r_d, r_d, buf, BN_NIST_384_TOP);
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);
carry += bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP);
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);
carry += bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP);
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);
carry += bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2),
t_d, BN_NIST_256_TOP);
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);
carry += bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP);
if (carry)
bn_sub_words(r_d, r_d, _384_data + BN_NIST_384_TOP *
(carry-1), BN_NIST_384_TOP);
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);
carry = bn_sub_words(r_d, r_d, t_d, 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));
#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);
carry += bn_sub_words(r_d, r_d, t_d, 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));
#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
/*D3*/
nist_set_384(t_d,buf,0,0,0,0,0,0,0,23,23,0,0,0);
carry += bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP);
if (carry)
bn_add_words(r_d, r_d, _384_data + BN_NIST_384_TOP *
(carry-1), 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)
{
bn_sub_words(r_d, r_d, _nist_p_384, BN_NIST_384_TOP);
bn_correct_top(r);
}
bn_check_top(r);
return 1;
#else
return 0;