本文整理汇总了C++中BN_CTX_get函数的典型用法代码示例。如果您正苦于以下问题：C++ BN_CTX_get函数的具体用法？C++ BN_CTX_get怎么用？C++ BN_CTX_get使用的例子？那么恭喜您, 这里精选的函数代码示例或许可以为您提供帮助。
在下文中一共展示了BN_CTX_get函数的20个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于我们的系统推荐出更棒的C++代码示例。
示例1: bn_check_top
/* solves ax == 1 (mod n) */
BIGNUM *BN_mod_inverse(BIGNUM *in,
const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx)
{
BIGNUM *A,*B,*X,*Y,*M,*D,*T,*R=NULL;
BIGNUM *ret=NULL;
int sign;
bn_check_top(a);
bn_check_top(n);
BN_CTX_start(ctx);
A = BN_CTX_get(ctx);
B = BN_CTX_get(ctx);
X = BN_CTX_get(ctx);
D = BN_CTX_get(ctx);
M = BN_CTX_get(ctx);
Y = BN_CTX_get(ctx);
T = BN_CTX_get(ctx);
if (T == NULL) goto err;
if (in == NULL)
R=BN_new();
else
R=in;
if (R == NULL) goto err;
BN_one(X);
BN_zero(Y);
if (BN_copy(B,a) == NULL) goto err;
if (BN_copy(A,n) == NULL) goto err;
A->neg = 0;
if (B->neg || (BN_ucmp(B, A) >= 0))
{
if (!BN_nnmod(B, B, A, ctx)) goto err;
}
sign = -1;
/* From B = a mod |n|, A = |n| it follows that
*
* 0 <= B < A,
* -sign*X*a == B (mod |n|),
* sign*Y*a == A (mod |n|).
*/
if (BN_is_odd(n) && (BN_num_bits(n) <= (BN_BITS <= 32 ? 450 : 2048)))
{
/* Binary inversion algorithm; requires odd modulus.
* This is faster than the general algorithm if the modulus
* is sufficiently small (about 400 .. 500 bits on 32-bit
* sytems, but much more on 64-bit systems) */
int shift;
while (!BN_is_zero(B))
{
/*
* 0 < B < |n|,
* 0 < A <= |n|,
* (1) -sign*X*a == B (mod |n|),
* (2) sign*Y*a == A (mod |n|)
*/
/* Now divide B by the maximum possible power of two in the integers,
* and divide X by the same value mod |n|.
* When we're done, (1) still holds. */
shift = 0;
while (!BN_is_bit_set(B, shift)) /* note that 0 < B */
{
shift++;
if (BN_is_odd(X))
{
if (!BN_uadd(X, X, n)) goto err;
}
/* now X is even, so we can easily divide it by two */
if (!BN_rshift1(X, X)) goto err;
}
if (shift > 0)
{
if (!BN_rshift(B, B, shift)) goto err;
}
/* Same for A and Y. Afterwards, (2) still holds. */
shift = 0;
while (!BN_is_bit_set(A, shift)) /* note that 0 < A */
{
shift++;
if (BN_is_odd(Y))
{
if (!BN_uadd(Y, Y, n)) goto err;
}
/* now Y is even */
if (!BN_rshift1(Y, Y)) goto err;
}
if (shift > 0)
{
if (!BN_rshift(A, A, shift)) goto err;
}
//.........这里部分代码省略.........
开发者ID:12019，项目名称:svn.gov.pt，代码行数:101，代码来源:bn_gcd.c
示例2: ec_GFp_simple_is_on_curve
int ec_GFp_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point, BN_CTX *ctx)
{
int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, BN_CTX *);
int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *);
const BIGNUM *p;
BN_CTX *new_ctx = NULL;
BIGNUM *rh, *tmp, *Z4, *Z6;
int ret = -1;
if (EC_POINT_is_at_infinity(group, point))
return 1;
field_mul = group->meth->field_mul;
field_sqr = group->meth->field_sqr;
p = &group->field;
if (ctx == NULL)
{
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return -1;
}
BN_CTX_start(ctx);
rh = BN_CTX_get(ctx);
tmp = BN_CTX_get(ctx);
Z4 = BN_CTX_get(ctx);
Z6 = BN_CTX_get(ctx);
if (Z6 == NULL) goto err;
/* We have a curve defined by a Weierstrass equation
* y^2 = x^3 + a*x + b.
* The point to consider is given in Jacobian projective coordinates
* where (X, Y, Z) represents (x, y) = (X/Z^2, Y/Z^3).
* Substituting this and multiplying by Z^6 transforms the above equation into
* Y^2 = X^3 + a*X*Z^4 + b*Z^6.
* To test this, we add up the right-hand side in 'rh'.
*/
/* rh := X^2 */
if (!field_sqr(group, rh, &point->X, ctx)) goto err;
if (!point->Z_is_one)
{
if (!field_sqr(group, tmp, &point->Z, ctx)) goto err;
if (!field_sqr(group, Z4, tmp, ctx)) goto err;
if (!field_mul(group, Z6, Z4, tmp, ctx)) goto err;
/* rh := (rh + a*Z^4)*X */
if (group->a_is_minus3)
{
if (!BN_mod_lshift1_quick(tmp, Z4, p)) goto err;
if (!BN_mod_add_quick(tmp, tmp, Z4, p)) goto err;
if (!BN_mod_sub_quick(rh, rh, tmp, p)) goto err;
if (!field_mul(group, rh, rh, &point->X, ctx)) goto err;
}
else
{
if (!field_mul(group, tmp, Z4, &group->a, ctx)) goto err;
if (!BN_mod_add_quick(rh, rh, tmp, p)) goto err;
if (!field_mul(group, rh, rh, &point->X, ctx)) goto err;
}
/* rh := rh + b*Z^6 */
if (!field_mul(group, tmp, &group->b, Z6, ctx)) goto err;
if (!BN_mod_add_quick(rh, rh, tmp, p)) goto err;
}
else
{
/* point->Z_is_one */
/* rh := (rh + a)*X */
if (!BN_mod_add_quick(rh, rh, &group->a, p)) goto err;
if (!field_mul(group, rh, rh, &point->X, ctx)) goto err;
/* rh := rh + b */
if (!BN_mod_add_quick(rh, rh, &group->b, p)) goto err;
}
/* 'lh' := Y^2 */
if (!field_sqr(group, tmp, &point->Y, ctx)) goto err;
ret = (0 == BN_ucmp(tmp, rh));
err:
BN_CTX_end(ctx);
if (new_ctx != NULL)
BN_CTX_free(new_ctx);
return ret;
}
开发者ID:Nymphetaminer，项目名称:dsl-n55u，代码行数:89，代码来源:ecp_smpl.c
示例3: ec_GFp_simple_points_make_affine
int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, EC_POINT *points[], BN_CTX *ctx)
{
BN_CTX *new_ctx = NULL;
BIGNUM *tmp, *tmp_Z;
BIGNUM **prod_Z = NULL;
size_t i;
int ret = 0;
if (num == 0)
return 1;
if (ctx == NULL)
{
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return 0;
}
BN_CTX_start(ctx);
tmp = BN_CTX_get(ctx);
tmp_Z = BN_CTX_get(ctx);
if (tmp == NULL || tmp_Z == NULL) goto err;
prod_Z = OPENSSL_malloc(num * sizeof prod_Z[0]);
if (prod_Z == NULL) goto err;
for (i = 0; i < num; i++)
{
prod_Z[i] = BN_new();
if (prod_Z[i] == NULL) goto err;
}
/* Set each prod_Z[i] to the product of points[0]->Z .. points[i]->Z,
* skipping any zero-valued inputs (pretend that they're 1). */
if (!BN_is_zero(&points[0]->Z))
{
if (!BN_copy(prod_Z[0], &points[0]->Z)) goto err;
}
else
{
if (group->meth->field_set_to_one != 0)
{
if (!group->meth->field_set_to_one(group, prod_Z[0], ctx)) goto err;
}
else
{
if (!BN_one(prod_Z[0])) goto err;
}
}
for (i = 1; i < num; i++)
{
if (!BN_is_zero(&points[i]->Z))
{
if (!group->meth->field_mul(group, prod_Z[i], prod_Z[i - 1], &points[i]->Z, ctx)) goto err;
}
else
{
if (!BN_copy(prod_Z[i], prod_Z[i - 1])) goto err;
}
}
/* Now use a single explicit inversion to replace every
* non-zero points[i]->Z by its inverse. */
if (!BN_mod_inverse(tmp, prod_Z[num - 1], &group->field, ctx))
{
ECerr(EC_F_EC_GFP_SIMPLE_POINTS_MAKE_AFFINE, ERR_R_BN_LIB);
goto err;
}
if (group->meth->field_encode != 0)
{
/* In the Montgomery case, we just turned R*H (representing H)
* into 1/(R*H), but we need R*(1/H) (representing 1/H);
* i.e. we need to multiply by the Montgomery factor twice. */
if (!group->meth->field_encode(group, tmp, tmp, ctx)) goto err;
if (!group->meth->field_encode(group, tmp, tmp, ctx)) goto err;
}
for (i = num - 1; i > 0; --i)
{
/* Loop invariant: tmp is the product of the inverses of
* points[0]->Z .. points[i]->Z (zero-valued inputs skipped). */
if (!BN_is_zero(&points[i]->Z))
{
/* Set tmp_Z to the inverse of points[i]->Z (as product
* of Z inverses 0 .. i, Z values 0 .. i - 1). */
if (!group->meth->field_mul(group, tmp_Z, prod_Z[i - 1], tmp, ctx)) goto err;
/* Update tmp to satisfy the loop invariant for i - 1. */
if (!group->meth->field_mul(group, tmp, tmp, &points[i]->Z, ctx)) goto err;
/* Replace points[i]->Z by its inverse. */
if (!BN_copy(&points[i]->Z, tmp_Z)) goto err;
}
}
if (!BN_is_zero(&points[0]->Z))
{
/* Replace points[0]->Z by its inverse. */
if (!BN_copy(&points[0]->Z, tmp)) goto err;
}
//.........这里部分代码省略.........
开发者ID:Nymphetaminer，项目名称:dsl-n55u，代码行数:101，代码来源:ecp_smpl.c
示例4: ec_GFp_simple_oct2point
int ec_GFp_simple_oct2point(const EC_GROUP *group, EC_POINT *point,
const unsigned char *buf, size_t len, BN_CTX *ctx)
{
point_conversion_form_t form;
int y_bit;
BN_CTX *new_ctx = NULL;
BIGNUM *x, *y;
size_t field_len, enc_len;
int ret = 0;
if (len == 0)
{
ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_BUFFER_TOO_SMALL);
return 0;
}
form = buf[0];
y_bit = form & 1;
form = form & ~1U;
if ((form != 0) && (form != POINT_CONVERSION_COMPRESSED)
&& (form != POINT_CONVERSION_UNCOMPRESSED)
&& (form != POINT_CONVERSION_HYBRID))
{
ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
return 0;
}
if ((form == 0 || form == POINT_CONVERSION_UNCOMPRESSED) && y_bit)
{
ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
return 0;
}
if (form == 0)
{
if (len != 1)
{
ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
return 0;
}
return EC_POINT_set_to_infinity(group, point);
}
field_len = BN_num_bytes(&group->field);
enc_len = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2*field_len;
if (len != enc_len)
{
ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
return 0;
}
if (ctx == NULL)
{
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return 0;
}
BN_CTX_start(ctx);
x = BN_CTX_get(ctx);
y = BN_CTX_get(ctx);
if (y == NULL) goto err;
if (!BN_bin2bn(buf + 1, field_len, x)) goto err;
if (BN_ucmp(x, &group->field) >= 0)
{
ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
goto err;
}
if (form == POINT_CONVERSION_COMPRESSED)
{
if (!EC_POINT_set_compressed_coordinates_GFp(group, point, x, y_bit, ctx)) goto err;
}
else
{
if (!BN_bin2bn(buf + 1 + field_len, field_len, y)) goto err;
if (BN_ucmp(y, &group->field) >= 0)
{
ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
goto err;
}
if (form == POINT_CONVERSION_HYBRID)
{
if (y_bit != BN_is_odd(y))
{
ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
goto err;
}
}
if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx)) goto err;
}
if (!EC_POINT_is_on_curve(group, point, ctx)) /* test required by X9.62 */
{
ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_POINT_IS_NOT_ON_CURVE);
goto err;
}
//.........这里部分代码省略.........
开发者ID:Valbonjv，项目名称:QuickSMS，代码行数:101，代码来源:ecp_oct.c
示例5: ec_GFp_simple_add
int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, const EC_POINT *b, BN_CTX *ctx)
{
int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, BN_CTX *);
int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *);
const BIGNUM *p;
BN_CTX *new_ctx = NULL;
BIGNUM *n0, *n1, *n2, *n3, *n4, *n5, *n6;
int ret = 0;
if (a == b)
return EC_POINT_dbl(group, r, a, ctx);
if (EC_POINT_is_at_infinity(group, a))
return EC_POINT_copy(r, b);
if (EC_POINT_is_at_infinity(group, b))
return EC_POINT_copy(r, a);
field_mul = group->meth->field_mul;
field_sqr = group->meth->field_sqr;
p = &group->field;
if (ctx == NULL)
{
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return 0;
}
BN_CTX_start(ctx);
n0 = BN_CTX_get(ctx);
n1 = BN_CTX_get(ctx);
n2 = BN_CTX_get(ctx);
n3 = BN_CTX_get(ctx);
n4 = BN_CTX_get(ctx);
n5 = BN_CTX_get(ctx);
n6 = BN_CTX_get(ctx);
if (n6 == NULL) goto end;
/* Note that in this function we must not read components of 'a' or 'b'
* once we have written the corresponding components of 'r'.
* ('r' might be one of 'a' or 'b'.)
*/
/* n1, n2 */
if (b->Z_is_one)
{
if (!BN_copy(n1, &a->X)) goto end;
if (!BN_copy(n2, &a->Y)) goto end;
/* n1 = X_a */
/* n2 = Y_a */
}
else
{
if (!field_sqr(group, n0, &b->Z, ctx)) goto end;
if (!field_mul(group, n1, &a->X, n0, ctx)) goto end;
/* n1 = X_a * Z_b^2 */
if (!field_mul(group, n0, n0, &b->Z, ctx)) goto end;
if (!field_mul(group, n2, &a->Y, n0, ctx)) goto end;
/* n2 = Y_a * Z_b^3 */
}
/* n3, n4 */
if (a->Z_is_one)
{
if (!BN_copy(n3, &b->X)) goto end;
if (!BN_copy(n4, &b->Y)) goto end;
/* n3 = X_b */
/* n4 = Y_b */
}
else
{
if (!field_sqr(group, n0, &a->Z, ctx)) goto end;
if (!field_mul(group, n3, &b->X, n0, ctx)) goto end;
/* n3 = X_b * Z_a^2 */
if (!field_mul(group, n0, n0, &a->Z, ctx)) goto end;
if (!field_mul(group, n4, &b->Y, n0, ctx)) goto end;
/* n4 = Y_b * Z_a^3 */
}
/* n5, n6 */
if (!BN_mod_sub_quick(n5, n1, n3, p)) goto end;
if (!BN_mod_sub_quick(n6, n2, n4, p)) goto end;
/* n5 = n1 - n3 */
/* n6 = n2 - n4 */
if (BN_is_zero(n5))
{
if (BN_is_zero(n6))
{
/* a is the same point as b */
BN_CTX_end(ctx);
ret = EC_POINT_dbl(group, r, a, ctx);
ctx = NULL;
goto end;
}
else
{
/* a is the inverse of b */
BN_zero(&r->Z);
//.........这里部分代码省略.........
开发者ID:Nymphetaminer，项目名称:dsl-n55u，代码行数:101，代码来源:ecp_smpl.c
示例6: DH_check
int DH_check(const DH *dh, int *ret)
{
int ok=0;
BN_CTX *ctx=NULL;
BN_ULONG l;
BIGNUM *t1=NULL, *t2 = NULL;
*ret=0;
ctx=BN_CTX_new();
if (ctx == NULL) goto err;
BN_CTX_start(ctx);
t1=BN_CTX_get(ctx);
if (t1 == NULL) goto err;
t2=BN_CTX_get(ctx);
if (t2 == NULL) goto err;
if (dh->q)
{
if (BN_cmp(dh->g, BN_value_one()) <= 0)
*ret|=DH_NOT_SUITABLE_GENERATOR;
else if (BN_cmp(dh->g, dh->p) >= 0)
*ret|=DH_NOT_SUITABLE_GENERATOR;
else
{
/* Check g^q == 1 mod p */
if (!BN_mod_exp(t1, dh->g, dh->q, dh->p, ctx))
goto err;
if (!BN_is_one(t1))
*ret|=DH_NOT_SUITABLE_GENERATOR;
}
if (!BN_is_prime_ex(dh->q,BN_prime_checks,ctx,NULL))
*ret|=DH_CHECK_Q_NOT_PRIME;
/* Check p == 1 mod q i.e. q divides p - 1 */
if (!BN_div(t1, t2, dh->p, dh->q, ctx))
goto err;
if (!BN_is_one(t2))
*ret|=DH_CHECK_INVALID_Q_VALUE;
if (dh->j && BN_cmp(dh->j, t1))
*ret|=DH_CHECK_INVALID_J_VALUE;
}
else if (BN_is_word(dh->g,DH_GENERATOR_2))
{
l=BN_mod_word(dh->p,24);
if (l != 11) *ret|=DH_NOT_SUITABLE_GENERATOR;
}
#if 0
else if (BN_is_word(dh->g,DH_GENERATOR_3))
{
l=BN_mod_word(dh->p,12);
if (l != 5) *ret|=DH_NOT_SUITABLE_GENERATOR;
}
#endif
else if (BN_is_word(dh->g,DH_GENERATOR_5))
{
l=BN_mod_word(dh->p,10);
if ((l != 3) && (l != 7))
*ret|=DH_NOT_SUITABLE_GENERATOR;
}
else
*ret|=DH_UNABLE_TO_CHECK_GENERATOR;
if (!BN_is_prime_ex(dh->p,BN_prime_checks,ctx,NULL))
*ret|=DH_CHECK_P_NOT_PRIME;
else if (!dh->q)
{
if (!BN_rshift1(t1,dh->p)) goto err;
if (!BN_is_prime_ex(t1,BN_prime_checks,ctx,NULL))
*ret|=DH_CHECK_P_NOT_SAFE_PRIME;
}
ok=1;
err:
if (ctx != NULL)
{
BN_CTX_end(ctx);
BN_CTX_free(ctx);
}
return(ok);
}
开发者ID:0culus，项目名称:openssl，代码行数:79，代码来源:dh_check.c
示例7: BN_X931_derive_prime_ex
int BN_X931_derive_prime_ex(BIGNUM *p, BIGNUM *p1, BIGNUM *p2,
const BIGNUM *Xp, const BIGNUM *Xp1, const BIGNUM *Xp2,
const BIGNUM *e, BN_CTX *ctx, BN_GENCB *cb)
{
int ret = 0;
BIGNUM *t, *p1p2, *pm1;
/* Only even e supported */
if (!BN_is_odd(e))
return 0;
BN_CTX_start(ctx);
if (!p1)
p1 = BN_CTX_get(ctx);
if (!p2)
p2 = BN_CTX_get(ctx);
t = BN_CTX_get(ctx);
p1p2 = BN_CTX_get(ctx);
pm1 = BN_CTX_get(ctx);
if (!bn_x931_derive_pi(p1, Xp1, ctx, cb))
goto err;
if (!bn_x931_derive_pi(p2, Xp2, ctx, cb))
goto err;
if (!BN_mul(p1p2, p1, p2, ctx))
goto err;
/* First set p to value of Rp */
if (!BN_mod_inverse(p, p2, p1, ctx))
goto err;
if (!BN_mul(p, p, p2, ctx))
goto err;
if (!BN_mod_inverse(t, p1, p2, ctx))
goto err;
if (!BN_mul(t, t, p1, ctx))
goto err;
if (!BN_sub(p, p, t))
goto err;
if (p->neg && !BN_add(p, p, p1p2))
goto err;
/* p now equals Rp */
if (!BN_mod_sub(p, p, Xp, p1p2, ctx))
goto err;
if (!BN_add(p, p, Xp))
goto err;
/* p now equals Yp0 */
for (;;)
{
int i = 1;
BN_GENCB_call(cb, 0, i++);
if (!BN_copy(pm1, p))
goto err;
if (!BN_sub_word(pm1, 1))
goto err;
if (!BN_gcd(t, pm1, e, ctx))
goto err;
if (BN_is_one(t)
/* X9.31 specifies 8 MR and 1 Lucas test or any prime test
* offering similar or better guarantees 50 MR is considerably
* better.
*/
&& BN_is_prime_fasttest_ex(p, 50, ctx, 1, cb))
break;
if (!BN_add(p, p, p1p2))
goto err;
}
BN_GENCB_call(cb, 3, 0);
ret = 1;
err:
BN_CTX_end(ctx);
return ret;
}
开发者ID:alisw，项目名称:alice-openssl，代码行数:95，代码来源:bn_x931p.c
示例8: RSA_recover_crt_params
int RSA_recover_crt_params(RSA *rsa) {
BN_CTX *ctx;
BIGNUM *totient, *rem, *multiple, *p_plus_q, *p_minus_q;
int ok = 0;
if (rsa->n == NULL || rsa->e == NULL || rsa->d == NULL) {
OPENSSL_PUT_ERROR(RSA, RSA_R_EMPTY_PUBLIC_KEY);
return 0;
}
if (rsa->p || rsa->q || rsa->dmp1 || rsa->dmq1 || rsa->iqmp) {
OPENSSL_PUT_ERROR(RSA, RSA_R_CRT_PARAMS_ALREADY_GIVEN);
return 0;
}
if (rsa->additional_primes != NULL) {
OPENSSL_PUT_ERROR(RSA, RSA_R_CANNOT_RECOVER_MULTI_PRIME_KEY);
return 0;
}
/* This uses the algorithm from section 9B of the RSA paper:
* http://people.csail.mit.edu/rivest/Rsapaper.pdf */
ctx = BN_CTX_new();
if (ctx == NULL) {
OPENSSL_PUT_ERROR(RSA, ERR_R_MALLOC_FAILURE);
return 0;
}
BN_CTX_start(ctx);
totient = BN_CTX_get(ctx);
rem = BN_CTX_get(ctx);
multiple = BN_CTX_get(ctx);
p_plus_q = BN_CTX_get(ctx);
p_minus_q = BN_CTX_get(ctx);
if (totient == NULL || rem == NULL || multiple == NULL || p_plus_q == NULL ||
p_minus_q == NULL) {
OPENSSL_PUT_ERROR(RSA, ERR_R_MALLOC_FAILURE);
goto err;
}
/* ed-1 is a small multiple of φ(n). */
if (!BN_mul(totient, rsa->e, rsa->d, ctx) ||
!BN_sub_word(totient, 1) ||
/* φ(n) =
* pq - p - q + 1 =
* n - (p + q) + 1
*
* Thus n is a reasonable estimate for φ(n). So, (ed-1)/n will be very
* close. But, when we calculate the quotient, we'll be truncating it
* because we discard the remainder. Thus (ed-1)/multiple will be >= n,
* which the totient cannot be. So we add one to the estimate.
*
* Consider ed-1 as:
*
* multiple * (n - (p+q) + 1) =
* multiple*n - multiple*(p+q) + multiple
*
* When we divide by n, the first term becomes multiple and, since
* multiple and p+q is tiny compared to n, the second and third terms can
* be ignored. Thus I claim that subtracting one from the estimate is
* sufficient. */
!BN_div(multiple, NULL, totient, rsa->n, ctx) ||
!BN_add_word(multiple, 1) ||
!BN_div(totient, rem, totient, multiple, ctx)) {
OPENSSL_PUT_ERROR(RSA, ERR_R_BN_LIB);
goto err;
}
if (!BN_is_zero(rem)) {
OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_RSA_PARAMETERS);
goto err;
}
rsa->p = BN_new();
rsa->q = BN_new();
rsa->dmp1 = BN_new();
rsa->dmq1 = BN_new();
rsa->iqmp = BN_new();
if (rsa->p == NULL || rsa->q == NULL || rsa->dmp1 == NULL || rsa->dmq1 ==
NULL || rsa->iqmp == NULL) {
OPENSSL_PUT_ERROR(RSA, ERR_R_MALLOC_FAILURE);
goto err;
}
/* φ(n) = n - (p + q) + 1 =>
* n - totient + 1 = p + q */
if (!BN_sub(p_plus_q, rsa->n, totient) ||
!BN_add_word(p_plus_q, 1) ||
/* p - q = sqrt((p+q)^2 - 4n) */
!BN_sqr(rem, p_plus_q, ctx) ||
!BN_lshift(multiple, rsa->n, 2) ||
!BN_sub(rem, rem, multiple) ||
!BN_sqrt(p_minus_q, rem, ctx) ||
/* q is 1/2 (p+q)-(p-q) */
!BN_sub(rsa->q, p_plus_q, p_minus_q) ||
!BN_rshift1(rsa->q, rsa->q) ||
!BN_div(rsa->p, NULL, rsa->n, rsa->q, ctx) ||
!BN_mul(multiple, rsa->p, rsa->q, ctx)) {
//.........这里部分代码省略.........
开发者ID:Cyril2004，项目名称:proto-quic，代码行数:101，代码来源:rsa.c
示例9: gf2m_Mxy
/* Compute the x, y affine coordinates from the point (x1, z1) (x2, z2)
* using Montgomery point multiplication algorithm Mxy() in appendix of
* Lopez, J. and Dahab, R. "Fast multiplication on elliptic curves over
* GF(2^m) without precomputation" (CHES '99, LNCS 1717).
* Returns:
* 0 on error
* 1 if return value should be the point at infinity
* 2 otherwise
*/
static int
gf2m_Mxy(const EC_GROUP *group, const BIGNUM *x, const BIGNUM *y, BIGNUM *x1,
BIGNUM *z1, BIGNUM *x2, BIGNUM *z2, BN_CTX *ctx)
{
BIGNUM *t3, *t4, *t5;
int ret = 0;
if (BN_is_zero(z1)) {
BN_zero(x2);
BN_zero(z2);
return 1;
}
if (BN_is_zero(z2)) {
if (!BN_copy(x2, x))
return 0;
if (!BN_GF2m_add(z2, x, y))
return 0;
return 2;
}
/* Since Mxy is static we can guarantee that ctx != NULL. */
BN_CTX_start(ctx);
if ((t3 = BN_CTX_get(ctx)) == NULL)
goto err;
if ((t4 = BN_CTX_get(ctx)) == NULL)
goto err;
if ((t5 = BN_CTX_get(ctx)) == NULL)
goto err;
if (!BN_one(t5))
goto err;
if (!group->meth->field_mul(group, t3, z1, z2, ctx))
goto err;
if (!group->meth->field_mul(group, z1, z1, x, ctx))
goto err;
if (!BN_GF2m_add(z1, z1, x1))
goto err;
if (!group->meth->field_mul(group, z2, z2, x, ctx))
goto err;
if (!group->meth->field_mul(group, x1, z2, x1, ctx))
goto err;
if (!BN_GF2m_add(z2, z2, x2))
goto err;
if (!group->meth->field_mul(group, z2, z2, z1, ctx))
goto err;
if (!group->meth->field_sqr(group, t4, x, ctx))
goto err;
if (!BN_GF2m_add(t4, t4, y))
goto err;
if (!group->meth->field_mul(group, t4, t4, t3, ctx))
goto err;
if (!BN_GF2m_add(t4, t4, z2))
goto err;
if (!group->meth->field_mul(group, t3, t3, x, ctx))
goto err;
if (!group->meth->field_div(group, t3, t5, t3, ctx))
goto err;
if (!group->meth->field_mul(group, t4, t3, t4, ctx))
goto err;
if (!group->meth->field_mul(group, x2, x1, t3, ctx))
goto err;
if (!BN_GF2m_add(z2, x2, x))
goto err;
if (!group->meth->field_mul(group, z2, z2, t4, ctx))
goto err;
if (!BN_GF2m_add(z2, z2, y))
goto err;
ret = 2;
err:
BN_CTX_end(ctx);
return ret;
}
开发者ID:ajinkya93，项目名称:OpenBSD，代码行数:87，代码来源:ec2_mult.c
示例10: ec_GFp_simple_point2oct
static size_t ec_GFp_simple_point2oct(const EC_GROUP *group,
const EC_POINT *point,
point_conversion_form_t form,
uint8_t *buf, size_t len, BN_CTX *ctx) {
size_t ret;
BN_CTX *new_ctx = NULL;
int used_ctx = 0;
BIGNUM *x, *y;
size_t field_len, i;
if ((form != POINT_CONVERSION_COMPRESSED) &&
(form != POINT_CONVERSION_UNCOMPRESSED)) {
OPENSSL_PUT_ERROR(EC, EC_R_INVALID_FORM);
goto err;
}
if (EC_POINT_is_at_infinity(group, point)) {
OPENSSL_PUT_ERROR(EC, EC_R_POINT_AT_INFINITY);
goto err;
}
/* ret := required output buffer length */
field_len = BN_num_bytes(&group->field);
ret =
(form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len;
/* if 'buf' is NULL, just return required length */
if (buf != NULL) {
if (len < ret) {
OPENSSL_PUT_ERROR(EC, EC_R_BUFFER_TOO_SMALL);
goto err;
}
if (ctx == NULL) {
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL) {
goto err;
}
}
BN_CTX_start(ctx);
used_ctx = 1;
x = BN_CTX_get(ctx);
y = BN_CTX_get(ctx);
if (y == NULL) {
goto err;
}
if (!EC_POINT_get_affine_coordinates_GFp(group, point, x, y, ctx)) {
goto err;
}
if ((form == POINT_CONVERSION_COMPRESSED) &&
BN_is_odd(y)) {
buf[0] = form + 1;
} else {
buf[0] = form;
}
i = 1;
if (!BN_bn2bin_padded(buf + i, field_len, x)) {
OPENSSL_PUT_ERROR(EC, ERR_R_INTERNAL_ERROR);
goto err;
}
i += field_len;
if (form == POINT_CONVERSION_UNCOMPRESSED) {
if (!BN_bn2bin_padded(buf + i, field_len, y)) {
OPENSSL_PUT_ERROR(EC, ERR_R_INTERNAL_ERROR);
goto err;
}
i += field_len;
}
if (i != ret) {
OPENSSL_PUT_ERROR(EC, ERR_R_INTERNAL_ERROR);
goto err;
}
}
if (used_ctx) {
BN_CTX_end(ctx);
}
BN_CTX_free(new_ctx);
return ret;
err:
if (used_ctx) {
BN_CTX_end(ctx);
}
BN_CTX_free(new_ctx);
return 0;
}
开发者ID:Crawping，项目名称:chromium_extract，代码行数:93，代码来源:oct.c
示例11: BN_MONT_CTX_set
int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, BN_CTX *ctx)
{
int ret = 0;
BIGNUM *Ri,*R;
BN_CTX_start(ctx);
if((Ri = BN_CTX_get(ctx)) == NULL) goto err;
R= &(mont->RR); /* grab RR as a temp */
if (!BN_copy(&(mont->N),mod)) goto err; /* Set N */
mont->N.neg = 0;
#ifdef MONT_WORD
{
BIGNUM tmod;
BN_ULONG buf[2];
BN_init(&tmod);
tmod.d=buf;
tmod.dmax=2;
tmod.neg=0;
mont->ri=(BN_num_bits(mod)+(BN_BITS2-1))/BN_BITS2*BN_BITS2;
#if defined(OPENSSL_BN_ASM_MONT) && (BN_BITS2<=32)
/* Only certain BN_BITS2<=32 platforms actually make use of
* n0[1], and we could use the #else case (with a shorter R
* value) for the others. However, currently only the assembler
* files do know which is which. */
BN_zero(R);
if (!(BN_set_bit(R,2*BN_BITS2))) goto err;
tmod.top=0;
if ((buf[0] = mod->d[0])) tmod.top=1;
if ((buf[1] = mod->top>1 ? mod->d[1] : 0)) tmod.top=2;
if ((BN_mod_inverse(Ri,R,&tmod,ctx)) == NULL)
goto err;
if (!BN_lshift(Ri,Ri,2*BN_BITS2)) goto err; /* R*Ri */
if (!BN_is_zero(Ri))
{
if (!BN_sub_word(Ri,1)) goto err;
}
else /* if N mod word size == 1 */
{
if (bn_expand(Ri,(int)sizeof(BN_ULONG)*2) == NULL)
goto err;
/* Ri-- (mod double word size) */
Ri->neg=0;
Ri->d[0]=BN_MASK2;
Ri->d[1]=BN_MASK2;
Ri->top=2;
}
if (!BN_div(Ri,NULL,Ri,&tmod,ctx)) goto err;
/* Ni = (R*Ri-1)/N,
* keep only couple of least significant words: */
mont->n0[0] = (Ri->top > 0) ? Ri->d[0] : 0;
mont->n0[1] = (Ri->top > 1) ? Ri->d[1] : 0;
#else
BN_zero(R);
if (!(BN_set_bit(R,BN_BITS2))) goto err; /* R */
buf[0]=mod->d[0]; /* tmod = N mod word size */
buf[1]=0;
tmod.top = buf[0] != 0 ? 1 : 0;
/* Ri = R^-1 mod N*/
if ((BN_mod_inverse(Ri,R,&tmod,ctx)) == NULL)
goto err;
if (!BN_lshift(Ri,Ri,BN_BITS2)) goto err; /* R*Ri */
if (!BN_is_zero(Ri))
{
if (!BN_sub_word(Ri,1)) goto err;
}
else /* if N mod word size == 1 */
{
if (!BN_set_word(Ri,BN_MASK2)) goto err; /* Ri-- (mod word size) */
}
if (!BN_div(Ri,NULL,Ri,&tmod,ctx)) goto err;
/* Ni = (R*Ri-1)/N,
* keep only least significant word: */
mont->n0[0] = (Ri->top > 0) ? Ri->d[0] : 0;
mont->n0[1] = 0;
#endif
}
#else /* !MONT_WORD */
{ /* bignum version */
mont->ri=BN_num_bits(&mont->N);
BN_zero(R);
if (!BN_set_bit(R,mont->ri)) goto err; /* R = 2^ri */
/* Ri = R^-1 mod N*/
if ((BN_mod_inverse(Ri,R,&mont->N,ctx)) == NULL)
goto err;
if (!BN_lshift(Ri,Ri,mont->ri)) goto err; /* R*Ri */
if (!BN_sub_word(Ri,1)) goto err;
/* Ni = (R*Ri-1) / N */
if (!BN_div(&(mont->Ni),NULL,Ri,&mont->N,ctx)) goto err;
}
#endif
/* setup RR for conversions */
//.........这里部分代码省略.........
开发者ID:AdrianaPineda，项目名称:openssl，代码行数:101，代码来源:bn_mont.c
示例12: ec_GFp_simple_oct2point
static int ec_GFp_simple_oct2point(const EC_GROUP *group, EC_POINT *point,
const uint8_t *buf, size_t len,
BN_CTX *ctx) {
point_conversion_form_t form;
int y_bit;
BN_CTX *new_ctx = NULL;
BIGNUM *x, *y;
size_t field_len, enc_len;
int ret = 0;
if (len == 0) {
OPENSSL_PUT_ERROR(EC, EC_R_BUFFER_TOO_SMALL);
return 0;
}
form = buf[0];
y_bit = form & 1;
form = form & ~1U;
if ((form != POINT_CONVERSION_COMPRESSED &&
form != POINT_CONVERSION_UNCOMPRESSED) ||
(form == POINT_CONVERSION_UNCOMPRESSED && y_bit)) {
OPENSSL_PUT_ERROR(EC, EC_R_INVALID_ENCODING);
return 0;
}
field_len = BN_num_bytes(&group->field);
enc_len =
(form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len;
if (len != enc_len) {
OPENSSL_PUT_ERROR(EC, EC_R_INVALID_ENCODING);
return 0;
}
if (ctx == NULL) {
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL) {
return 0;
}
}
BN_CTX_start(ctx);
x = BN_CTX_get(ctx);
y = BN_CTX_get(ctx);
if (x == NULL || y == NULL) {
goto err;
}
if (!BN_bin2bn(buf + 1, field_len, x)) {
goto err;
}
if (BN_ucmp(x, &group->field) >= 0) {
OPENSSL_PUT_ERROR(EC, EC_R_INVALID_ENCODING);
goto err;
}
if (form == POINT_CONVERSION_COMPRESSED) {
if (!EC_POINT_set_compressed_coordinates_GFp(group, point, x, y_bit, ctx)) {
goto err;
}
} else {
if (!BN_bin2bn(buf + 1 + field_len, field_len, y)) {
goto err;
}
if (BN_ucmp(y, &group->field) >= 0) {
OPENSSL_PUT_ERROR(EC, EC_R_INVALID_ENCODING);
goto err;
}
if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx)) {
goto err;
}
}
ret = 1;
err:
BN_CTX_end(ctx);
BN_CTX_free(new_ctx);
return ret;
}
开发者ID:Crawping，项目名称:chromium_extract，代码行数:80，代码来源:oct.c
示例13: EC_GROUP_cmp
int EC_GROUP_cmp(const EC_GROUP *a, const EC_GROUP *b, BN_CTX *ctx)
{
int r = 0;
BIGNUM *a1, *a2, *a3, *b1, *b2, *b3;
BN_CTX *ctx_new = NULL;
/* compare the field types*/
if (EC_METHOD_get_field_type(EC_GROUP_method_of(a)) !=
EC_METHOD_get_field_type(EC_GROUP_method_of(b)))
return 1;
/* compare the curve name (if present) */
if (EC_GROUP_get_curve_name(a) && EC_GROUP_get_curve_name(b) &&
EC_GROUP_get_curve_name(a) == EC_GROUP_get_curve_name(b))
return 0;
if (!ctx)
ctx_new = ctx = BN_CTX_new();
if (!ctx)
return -1;
BN_CTX_start(ctx);
a1 = BN_CTX_get(ctx);
a2 = BN_CTX_get(ctx);
a3 = BN_CTX_get(ctx);
b1 = BN_CTX_get(ctx);
b2 = BN_CTX_get(ctx);
b3 = BN_CTX_get(ctx);
if (!b3)
{
BN_CTX_end(ctx);
if (ctx_new)
BN_CTX_free(ctx);
return -1;
}
/* XXX This approach assumes that the external representation
* of curves over the same field type is the same.
*/
if (!a->meth->group_get_curve(a, a1, a2, a3, ctx) ||
!b->meth->group_get_curve(b, b1, b2, b3, ctx))
r = 1;
if (r || BN_cmp(a1, b1) || BN_cmp(a2, b2) || BN_cmp(a3, b3))
r = 1;
/* XXX EC_POINT_cmp() assumes that the methods are equal */
if (r || EC_POINT_cmp(a, EC_GROUP_get0_generator(a),
EC_GROUP_get0_generator(b), ctx))
r = 1;
if (!r)
{
/* compare the order and cofactor */
if (!EC_GROUP_get_order(a, a1, ctx) ||
!EC_GROUP_get_order(b, b1, ctx) ||
!EC_GROUP_get_cofactor(a, a2, ctx) ||
!EC_GROUP_get_cofactor(b, b2, ctx))
{
BN_CTX_end(ctx);
if (ctx_new)
BN_CTX_free(ctx);
return -1;
}
if (BN_cmp(a1, b1) || BN_cmp(a2, b2))
r = 1;
}
BN_CTX_end(ctx);
if (ctx_new)
BN_CTX_free(ctx);
return r;
}
开发者ID:AustinWise，项目名称:Netduino-Micro-Framework，代码行数:73，代码来源:ec_lib.cpp
示例14: ssl_ec_point_finish
static int ssl_ec_point_finish(SSL_ECDH_CTX *ctx, uint8_t **out_secret,
size_t *out_secret_len, uint8_t *out_alert,
const uint8_t *peer_key, size_t peer_key_len) {
BIGNUM *private_key = (BIGNUM *)ctx->data;
assert(private_key != NULL);
*out_alert = SSL_AD_INTERNAL_ERROR;
/* Set up a shared |BN_CTX| for all operations. */
BN_CTX *bn_ctx = BN_CTX_new();
if (bn_ctx == NULL) {
return 0;
}
BN_CTX_start(bn_ctx);
int ret = 0;
EC_GROUP *group = EC_GROUP_new_by_curve_name(ctx->method->nid);
EC_POINT *peer_point = NULL, *result = NULL;
uint8_t *secret = NULL;
if (group == NULL) {
goto err;
}
/* Compute the x-coordinate of |peer_key| * |private_key|. */
peer_point = EC_POINT_new(group);
result = EC_POINT_new(group);
if (peer_point == NULL || result == NULL) {
goto err;
}
BIGNUM *x = BN_CTX_get(bn_ctx);
if (x == NULL) {
goto err;
}
if (!EC_POINT_oct2point(group, peer_point, peer_key, peer_key_len, bn_ctx)) {
*out_alert = SSL_AD_DECODE_ERROR;
goto err;
}
if (!EC_POINT_mul(group, result, NULL, peer_point, private_key, bn_ctx) ||
!EC_POINT_get_affine_coordinates_GFp(group, result, x, NULL, bn_ctx)) {
goto err;
}
/* Encode the x-coordinate left-padded with zeros. */
size_t secret_len = (EC_GROUP_get_degree(group) + 7) / 8;
secret = OPENSSL_malloc(secret_len);
if (secret == NULL || !BN_bn2bin_padded(secret, secret_len, x)) {
goto err;
}
*out_secret = secret;
*out_secret_len = secret_len;
secret = NULL;
ret = 1;
err:
EC_GROUP_free(group);
EC_POINT_free(peer_point);
EC_POINT_free(result);
BN_CTX_end(bn_ctx);
BN_CTX_free(bn_ctx);
OPENSSL_free(secret);
return ret;
}
开发者ID:chjp2046，项目名称:boringssl，代码行数:62，代码来源:ssl_ecdh.c
示例15: BN_new
BIGNUM *BN_mod_sqrt(BIGNUM *in, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx) {
// Compute a square root of |a| mod |p| using the Tonelli/Shanks algorithm
// (cf. Henri Cohen, "A Course in Algebraic Computational Number Theory",
// algorithm 1.5.1). |p| is assumed to be a prime.
BIGNUM *ret = in;
int err = 1;
int r;
BIGNUM *A, *b, *q, *t, *x, *y;
int e, i, j;
if (!BN_is_odd(p) || BN_abs_is_word(p, 1)) {
if (BN_abs_is_word(p, 2)) {
if (ret == NULL) {
ret = BN_new();
}
if (ret == NULL) {
goto end;
}
if (!BN_set_word(ret, BN_is_bit_set(a, 0))) {
if (ret != in) {
BN_free(ret);
}
return NULL;
}
return ret;
}
OPENSSL_PUT_ERROR(BN, BN_R_P_IS_NOT_PRIME);
return (NULL);
}
if (BN_is_zero(a) || BN_is_one(a)) {
if (ret == NULL) {
ret = BN_new();
}
if (ret == NULL) {
goto end;
}
if (!BN_set_word(ret, BN_is_one(a))) {
if (ret != in) {
BN_free(ret);
}
return NULL;
}
return ret;
}
BN_CTX_start(ctx);
A = BN_CTX_get(ctx);
b = BN_CTX_get(ctx);
q = BN_CTX_get(ctx);
t = BN_CTX_get(ctx);
x = BN_CTX_get(ctx);
y = BN_CTX_get(ctx);
if (y == NULL) {
goto end;
}
if (ret == NULL) {
ret = BN_new();
}
if (ret == NULL) {
goto end;
}
// A = a mod p
if (!BN_nnmod(A, a, p, ctx)) {
goto end;
}
// now write |p| - 1 as 2^e*q where q is odd
e = 1;
while (!BN_is_bit_set(p, e)) {
e++;
}
// we'll set q later (if needed)
if (e == 1) {
// The easy case: (|p|-1)/2 is odd, so 2 has an inverse
// modulo (|p|-1)/2, and square roots can be computed
// directly by modular exponentiation.
// We have
// 2 * (|p|+1)/4 == 1 (mod (|p|-1)/2),
// so we can use exponent (|p|+1)/4, i.e. (|p|-3)/4 + 1.
if (!BN_rshift(q, p, 2)) {
goto end;
}
q->neg = 0;
if (!BN_add_word(q, 1) ||
!BN_mod_exp_mont(ret, A, q, p, ctx, NULL)) {
goto end;
}
err = 0;
goto vrfy;
}
if (e == 2) {
// |p| == 5 (mod 8)
//
//.........这里部分代码省略.........
开发者ID:MateusDeSousa，项目名称:FiqueRico，代码行数:101，代码来源:sqrt.c
示例16: ec_GF2m_montgomery_point_multiply
/* Computes scalar*point and stores the result in r.
* point can not equal r.
* Uses a modified algorithm 2P of
* Lopez, J. and Dahab, R. "Fast multiplication on elliptic curves over
* GF(2^m) without precomputation" (CHES '99, LNCS 1717).
*
* To protect against side-channel attack the function uses constant time swap,
* avoiding conditional branches.
*/
static int
ec_GF2m_montgomery_point_multiply(const EC_GROUP *group, EC_POINT *r,
const BIGNUM *scalar, const EC_POINT *point, BN_CTX *ctx)
{
BIGNUM *x1, *x2, *z1, *z2;
int ret = 0, i;
BN_ULONG mask, word;
if (r == point) {
ECerr(EC_F_EC_GF2M_MONTGOMERY_POINT_MULTIPLY, EC_R_INVALID_ARGUMENT);
return 0;
}
/* if result should be point at infinity */
if ((scalar == NULL) || BN_is_zero(scalar) || (point == NULL) ||
EC_POINT_is_at_infinity(group, point) > 0) {
return EC_POINT_set_to_infinity(group, r);
}
/* only support affine coordinates */
if (!point->Z_is_one)
return 0;
/* Since point_multiply is static we can guarantee that ctx != NULL. */
BN_CTX_start(ctx);
if ((x1 = BN_CTX_get(ctx)) == NULL)
goto err;
if ((z1 = BN_CTX_get(ctx)) == NULL)
goto err;
x2 = &r->X;
z2 = &r->Y;
if (!bn_wexpand(x1, group->field.top))
goto err;
if (!bn_wexpand(z1, group->field.top))
goto err;
if (!bn_wexpand(x2, group->field.top))
goto err;
if (!bn_wexpand(z2, group->field.top))
goto err;
if (!BN_GF2m_mod_arr(x1, &point->X, group->poly))
goto err; /* x1 = x */
if (!BN_one(z1))
goto err; /* z1 = 1 */
if (!group->meth->field_sqr(group, z2, x1, ctx))
goto err; /* z2 = x1^2 = x^2 */
if (!group->meth->field_sqr(group, x2, z2, ctx))
goto err;
if (!BN_GF2m_add(x2, x2, &group->b))
goto err; /* x2 = x^4 + b */
/* find top most bit and go one past it */
i = scalar->top - 1;
mask = BN_TBIT;
word = scalar->d[i];
while (!(word & mask))
mask >>= 1;
mask >>= 1;
/* if top most bit was at word break, go to next word */
if (!mask) {
i--;
mask = BN_TBIT;
}
for (; i >= 0; i--) {
word = scalar->d[i];
while (mask) {
BN_consttime_swap(word & mask, x1, x2, group->field.top);
BN_consttime_swap(word & mask, z1, z2, group->field.top);
if (!gf2m_Madd(group, &point->X, x2, z2, x1, z1, ctx))
goto err;
if (!gf2m_Mdouble(group, x1, z1, ctx))
goto err;
BN_consttime_swap(word & mask, x1, x2, group->field.top);
BN_consttime_swap(word & mask, z1, z2, group->field.top);
mask >>= 1;
}
mask = BN_TBIT;
}
/* convert out of "projective" coordinates */
i = gf2m_Mxy(group, &point->X, &point->Y, x1, z1, x2, z2, ctx);
if (i == 0)
goto err;
else if (i == 1) {
if (!EC_POINT_set_to_infinity(group, r))
goto err;
} else {
if (!BN_one(&r->Z))
goto err;
r->Z_is_one = 1;
}
//.........这里部分代码省略.........
开发者ID:ajinkya93，项目名称:OpenBSD，代码行数:101，代码来源:ec2_mult.c
示例17: BN_mod_sqrt
BIGNUM *
BN_mod_sqrt(BIGNUM *in, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx)
/* Returns 'ret' such that
* ret^2 == a (mod p),
* using the Tonelli/Shanks algorithm (cf. Henri Cohen, "A Course
* in Algebraic Computational Number Theory", algorithm 1.5.1).
* 'p' must be prime!
*/
{
BIGNUM *ret = in;
int err = 1;
int r;
BIGNUM *A, *b, *q, *t, *x, *y;
int e, i, j;
if (!BN_is_odd(p) || BN_abs_is_word(p, 1)) {
if (BN_abs_is_word(p, 2)) {
if (ret == NULL)
ret = BN_new();
if (ret == NULL)
goto end;
if (!BN_set_word(ret, BN_is_bit_set(a, 0))) {
if (ret != in)
BN_free(ret);
return NULL;
}
bn_check_top(ret);
return ret;
}
BNerr(BN_F_BN_MOD_SQRT, BN_R_P_IS_NOT_PRIME);
return (NULL);
}
if (BN_is_zero(a) || BN_is_one(a)) {
if (ret == NULL)
ret = BN_new();
if (ret == NULL)
goto end;
if (!BN_set_word(ret, BN_is_one(a))) {
if (ret != in)
BN_free(ret);
return NULL;
}
bn_check_top(ret);
return ret;
}
BN_CTX_start(ctx);
A = BN_CTX_get(ctx);
b = BN_CTX_get(ctx);
q = BN_CTX_get(ctx);
t = BN_CTX_get(ctx);
x = BN_CTX_get(ctx);
y = BN_CTX_get(ctx);
if (y == NULL)
goto end;
if (ret == NULL)
ret = BN_new();
if (ret == NULL)
goto end;
/* A = a mod p */
if (!BN_nnmod(A, a, p, ctx))
goto end;
/* now write |p| - 1 as 2^e*q where q is odd */
e = 1;
while (!BN_is_bit_set(p, e))
e++;
/* we'll set q later (if needed) */
if (e == 1) {
/* The easy case: (|p|-1)/2 is odd, so 2 has an inverse
* modulo (|p|-1)/2, and square roots can be computed
* directly by modular exponentiation.
* We have
* 2 * (|p|+1)/4 == 1 (mod (|p|-1)/2),
* so we can use exponent (|p|+1)/4, i.e. (|p|-3)/4 + 1.
*/
if (!BN_rshift(q, p, 2))
goto end;
q->neg = 0;
if (!BN_add_word(q, 1))
goto end;
if (!BN_mod_exp(ret, A, q, p, ctx))
goto end;
err = 0;
goto vrfy;
}
if (e == 2) {
/* |p| == 5 (mod 8)
*
* In this case 2 is always a non-square since
* Legendre(2,p) = (-1)^((p^2-1)/8) for any odd prime.
* So if a really is a square, then 2*a is a non-square.
* Thus for
* b := (2*a)^((|p|-5)/8),
//.........这里部分代码省略.........
开发者ID:busterb，项目名称:libssl-openbsd，代码行数:101，代码来源:bn_sqrt.c
示例18: ECDSA_SIG_recover_key_GFp
|
客服电话
APP下载
官方微信
请发表评论