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

Some changes for bn_gf2m.c: better error checking plus some minor

Browse Source 
optimizations.

Submitted by: Nils Larsch
This commit is contained in:
Geoff Thorpe 2003-11-25 03:41:20 +00:00
parent d7559f16cd
commit e1064adfd3
1 changed files with 48 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

76
crypto/bn/bn_gf2m.c
View File

@ -323,8 +323,12 @@ int BN_GF2m_mod_arr(BIGNUM *r, const BIGNUM *a, const unsigned int p[])
int n, dN, d0, d1; int n, dN, d0, d1;
BN_ULONG zz, *z; BN_ULONG zz, *z;
/* Since the algorithm does reduction in the r value, if a != r, copy the if (!p[0])
* contents of a into r so we can do reduction in r. /* reduction mod 1 => return 0 */
return BN_zero(r);
/* Since the algorithm does reduction in the r value, if a != r, copy
* the contents of a into r so we can do reduction in r.
*/ */
if (a != r) if (a != r)
{ {
@ -345,7 +349,7 @@ int BN_GF2m_mod_arr(BIGNUM *r, const BIGNUM *a, const unsigned int p[])
if (z[j] == 0) { j--; continue; } if (z[j] == 0) { j--; continue; }
z[j] = 0; z[j] = 0;
for (k = 1; p[k] > 0; k++) for (k = 1; p[k] != 0; k++)
{ {
/* reducing component t^p[k] */ /* reducing component t^p[k] */
n = p[0] - p[k]; n = p[0] - p[k];
@ -375,7 +379,7 @@ int BN_GF2m_mod_arr(BIGNUM *r, const BIGNUM *a, const unsigned int p[])
if (d0) z[dN] = (z[dN] << d1) >> d1; /* clear up the top d1 bits */ if (d0) z[dN] = (z[dN] << d1) >> d1; /* clear up the top d1 bits */
z[0] ^= zz; /* reduction t^0 component */ z[0] ^= zz; /* reduction t^0 component */
for (k = 1; p[k] > 0; k++) for (k = 1; p[k] != 0; k++)
{ {
BN_ULONG tmp_ulong; BN_ULONG tmp_ulong;
@ -408,7 +412,8 @@ int BN_GF2m_mod(BIGNUM *r, const BIGNUM *a, const BIGNUM *p)
const int max = BN_num_bits(p); const int max = BN_num_bits(p);
unsigned int *arr=NULL, ret = 0; unsigned int *arr=NULL, ret = 0;
if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err; if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err;
if (BN_GF2m_poly2arr(p, arr, max) > max) ret = BN_GF2m_poly2arr(p, arr, max);
if (!ret || ret > max)
{ {
BNerr(BN_F_BN_GF2M_MOD,BN_R_INVALID_LENGTH); BNerr(BN_F_BN_GF2M_MOD,BN_R_INVALID_LENGTH);
goto err; goto err;
@ -459,9 +464,9 @@ int BN_GF2m_mod_mul_arr(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const unsig
} }
bn_correct_top(s); bn_correct_top(s);
BN_GF2m_mod_arr(r, s, p); if (BN_GF2m_mod_arr(r, s, p))
bn_check_top(r);
ret = 1; ret = 1;
bn_check_top(r);
err: err:
BN_CTX_end(ctx); BN_CTX_end(ctx);
@ -481,7 +486,8 @@ int BN_GF2m_mod_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *p
const int max = BN_num_bits(p); const int max = BN_num_bits(p);
unsigned int *arr=NULL, ret = 0; unsigned int *arr=NULL, ret = 0;
if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err; if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err;
if (BN_GF2m_poly2arr(p, arr, max) > max) ret = BN_GF2m_poly2arr(p, arr, max);
if (!ret || ret > max)
{ {
BNerr(BN_F_BN_GF2M_MOD_MUL,BN_R_INVALID_LENGTH); BNerr(BN_F_BN_GF2M_MOD_MUL,BN_R_INVALID_LENGTH);
goto err; goto err;
@ -531,7 +537,8 @@ int BN_GF2m_mod_sqr(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx)
const int max = BN_num_bits(p); const int max = BN_num_bits(p);
unsigned int *arr=NULL, ret = 0; unsigned int *arr=NULL, ret = 0;
if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err; if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err;
if (BN_GF2m_poly2arr(p, arr, max) > max) ret = BN_GF2m_poly2arr(p, arr, max);
if (!ret || ret > max)
{ {
BNerr(BN_F_BN_GF2M_MOD_SQR,BN_R_INVALID_LENGTH); BNerr(BN_F_BN_GF2M_MOD_SQR,BN_R_INVALID_LENGTH);
goto err; goto err;
@ -567,10 +574,6 @@ int BN_GF2m_mod_inv(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx)
if (!BN_GF2m_mod(u, a, p)) goto err; if (!BN_GF2m_mod(u, a, p)) goto err;
if (!BN_copy(v, p)) goto err; if (!BN_copy(v, p)) goto err;
u->neg = 0; /* Need to set u->neg = 0 because BN_is_one(u) checks
* the neg flag of the bignum.
*/
if (BN_is_zero(u)) goto err; if (BN_is_zero(u)) goto err;
while (1) while (1)
@ -585,7 +588,7 @@ int BN_GF2m_mod_inv(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx)
if (!BN_rshift1(b, b)) goto err; if (!BN_rshift1(b, b)) goto err;
} }
if (BN_is_one(u)) break; if (BN_abs_is_word(u, 1)) break;
if (BN_num_bits(u) < BN_num_bits(v)) if (BN_num_bits(u) < BN_num_bits(v))
{ {
@ -679,10 +682,6 @@ int BN_GF2m_mod_div(BIGNUM *r, const BIGNUM *y, const BIGNUM *x, const BIGNUM *p
if (!BN_copy(b, p)) goto err; if (!BN_copy(b, p)) goto err;
if (!BN_zero(v)) goto err; if (!BN_zero(v)) goto err;
a->neg = 0; /* Need to set a->neg = 0 because BN_is_one(a) checks
* the neg flag of the bignum.
*/
while (!BN_is_odd(a)) while (!BN_is_odd(a))
{ {
if (!BN_rshift1(a, a)) goto err; if (!BN_rshift1(a, a)) goto err;
@ -703,7 +702,7 @@ int BN_GF2m_mod_div(BIGNUM *r, const BIGNUM *y, const BIGNUM *x, const BIGNUM *p
if (!BN_rshift1(v, v)) goto err; if (!BN_rshift1(v, v)) goto err;
} while (!BN_is_odd(b)); } while (!BN_is_odd(b));
} }
else if (BN_is_one(a)) else if (BN_abs_is_word(a, 1))
break; break;
else else
{ {
@ -763,9 +762,10 @@ int BN_GF2m_mod_exp_arr(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const unsig
BIGNUM *u; BIGNUM *u;
if (BN_is_zero(b)) if (BN_is_zero(b))
{
return(BN_one(r)); return(BN_one(r));
}
if (BN_abs_is_word(b, 1))
return (BN_copy(r, a) != NULL);
BN_CTX_start(ctx); BN_CTX_start(ctx);
@ -804,7 +804,8 @@ int BN_GF2m_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *p
const int max = BN_num_bits(p); const int max = BN_num_bits(p);
unsigned int *arr=NULL, ret = 0; unsigned int *arr=NULL, ret = 0;
if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err; if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err;
if (BN_GF2m_poly2arr(p, arr, max) > max) ret = BN_GF2m_poly2arr(p, arr, max);
if (!ret || ret > max)
{ {
BNerr(BN_F_BN_GF2M_MOD_EXP,BN_R_INVALID_LENGTH); BNerr(BN_F_BN_GF2M_MOD_EXP,BN_R_INVALID_LENGTH);
goto err; goto err;
@ -825,6 +826,10 @@ int BN_GF2m_mod_sqrt_arr(BIGNUM *r, const BIGNUM *a, const unsigned int p[], BN_
int ret = 0; int ret = 0;
BIGNUM *u; BIGNUM *u;
if (!p[0])
/* reduction mod 1 => return 0 */
return BN_zero(r);
BN_CTX_start(ctx); BN_CTX_start(ctx);
if ((u = BN_CTX_get(ctx)) == NULL) goto err; if ((u = BN_CTX_get(ctx)) == NULL) goto err;
@ -850,7 +855,8 @@ int BN_GF2m_mod_sqrt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx)
const int max = BN_num_bits(p); const int max = BN_num_bits(p);
unsigned int *arr=NULL, ret = 0; unsigned int *arr=NULL, ret = 0;
if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err; if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err;
if (BN_GF2m_poly2arr(p, arr, max) > max) ret = BN_GF2m_poly2arr(p, arr, max);
if (!ret || ret > max)
{ {
BNerr(BN_F_BN_GF2M_MOD_EXP,BN_R_INVALID_LENGTH); BNerr(BN_F_BN_GF2M_MOD_EXP,BN_R_INVALID_LENGTH);
goto err; goto err;
@ -871,6 +877,10 @@ int BN_GF2m_mod_solve_quad_arr(BIGNUM *r, const BIGNUM *a_, const unsigned int p
unsigned int j; unsigned int j;
BIGNUM *a, *z, *rho, *w, *w2, *tmp; BIGNUM *a, *z, *rho, *w, *w2, *tmp;
if (!p[0])
/* reduction mod 1 => return 0 */
return BN_zero(r);
BN_CTX_start(ctx); BN_CTX_start(ctx);
a = BN_CTX_get(ctx); a = BN_CTX_get(ctx);
z = BN_CTX_get(ctx); z = BN_CTX_get(ctx);
@ -951,7 +961,8 @@ int BN_GF2m_mod_solve_quad(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *
const int max = BN_num_bits(p); const int max = BN_num_bits(p);
unsigned int *arr=NULL, ret = 0; unsigned int *arr=NULL, ret = 0;
if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err; if ((arr = (unsigned int *)OPENSSL_malloc(sizeof(unsigned int) * max)) == NULL) goto err;
if (BN_GF2m_poly2arr(p, arr, max) > max) ret = BN_GF2m_poly2arr(p, arr, max);
if (!ret || ret > max)
{ {
BNerr(BN_F_BN_GF2M_MOD_SOLVE_QUAD,BN_R_INVALID_LENGTH); BNerr(BN_F_BN_GF2M_MOD_SOLVE_QUAD,BN_R_INVALID_LENGTH);
goto err; goto err;
@ -963,21 +974,28 @@ int BN_GF2m_mod_solve_quad(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *
return ret; return ret;
} }
/* Convert the bit-string representation of a polynomial a into an array /* Convert the bit-string representation of a polynomial
* ( \sum_{i=0}^n a_i * x^i , where a_0 is *not* zero) into an array
* of integers corresponding to the bits with non-zero coefficient. * of integers corresponding to the bits with non-zero coefficient.
* Up to max elements of the array will be filled. Return value is total * Up to max elements of the array will be filled. Return value is total
* number of coefficients that would be extracted if array was large enough. * number of coefficients that would be extracted if array was large enough.
*/ */
int BN_GF2m_poly2arr(const BIGNUM *a, unsigned int p[], int max) int BN_GF2m_poly2arr(const BIGNUM *a, unsigned int p[], int max)
{ {
int i, j, k; int i, j, k = 0;
BN_ULONG mask; BN_ULONG mask;
for (k = 0; k < max; k++) p[k] = 0; if (BN_is_zero(a) || !BN_is_bit_set(a, 0))
k = 0; /* a_0 == 0 => return error (the unsigned int array
* must be terminated by 0)
*/
return 0;
for (i = a->top - 1; i >= 0; i--) for (i = a->top - 1; i >= 0; i--)
{ {
if (!a->d[i])
/* skip word if a->d[i] == 0 */
continue;
mask = BN_TBIT; mask = BN_TBIT;
for (j = BN_BITS2 - 1; j >= 0; j--) for (j = BN_BITS2 - 1; j >= 0; j--)
{ {
@ -1001,7 +1019,7 @@ int BN_GF2m_arr2poly(const unsigned int p[], BIGNUM *a)
int i; int i;
BN_zero(a); BN_zero(a);
for (i = 0; p[i] > 0; i++) for (i = 0; p[i] != 0; i++)
{ {
BN_set_bit(a, p[i]); BN_set_bit(a, p[i]);
} }