Commit e869d4bd authored by Bodo Möller's avatar Bodo Möller
Browse files

More method functions.

parent 60428dbf

crypto/ec/ec.h

+2 −1
Original line number Diff line number Diff line
@@ -133,7 +133,7 @@ int EC_POINT_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a, BN_CTX *); 
int EC_POINT_is_at_infinity(const EC_GROUP *, const EC_POINT *);

int EC_POINT_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);



int EC_POINT_make_affine(const EC_GROUP *, const EC_POINT *, BN_CTX *);

int EC_POINT_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);
@@ -150,6 +150,7 @@ int EC_POINT_make_affine(const EC_GROUP *, const EC_POINT *, BN_CTX *); 


/* Function codes. */

#define EC_F_EC_GFP_SIMPLE_GROUP_SET_GENERATOR		 117

#define EC_F_EC_GFP_SIMPLE_MAKE_AFFINE			 118

#define EC_F_EC_GROUP_CLEAR_FREE			 103

#define EC_F_EC_GROUP_COPY				 102

#define EC_F_EC_GROUP_FREE				 104

crypto/ec/ec_err.c

+1 −0
Original line number Diff line number Diff line
@@ -67,6 +67,7 @@ 
static ERR_STRING_DATA EC_str_functs[]=

	{

{ERR_PACK(0,EC_F_EC_GFP_SIMPLE_GROUP_SET_GENERATOR,0),	"EC_GFP_SIMPLE_GROUP_SET_GENERATOR"},

{ERR_PACK(0,EC_F_EC_GFP_SIMPLE_MAKE_AFFINE,0),	"EC_GFP_SIMPLE_MAKE_AFFINE"},

{ERR_PACK(0,EC_F_EC_GROUP_CLEAR_FREE,0),	"EC_GROUP_clear_free"},

{ERR_PACK(0,EC_F_EC_GROUP_COPY,0),	"EC_GROUP_copy"},

{ERR_PACK(0,EC_F_EC_GROUP_FREE,0),	"EC_GROUP_free"},

crypto/ec/ec_lcl.h

+3 −3
Original line number Diff line number Diff line
@@ -99,7 +99,7 @@ struct ec_method_st { 
	/* used by EC_POINT_is_at_infinity, EC_POINT_is_on_curve, EC_POINT_make_affine */

	int (*is_at_infinity)(const EC_GROUP *, const EC_POINT *);

	int (*is_on_curve)(const EC_GROUP *, const EC_POINT *, BN_CTX *);

	int (*make_affine)(const EC_GROUP *, const EC_POINT *, BN_CTX *);

	int (*make_affine)(const EC_GROUP *, EC_POINT *, BN_CTX *);





	/* internal functions */
@@ -134,7 +134,7 @@ struct ec_group_st { 
	              * or abused for all kinds of fields, not just GF(p).)

	              * For characteristic  > 3,  the curve is defined

	              * by a Weierstrass equation of the form

	              *     Y^2 = X^3 + a*X + b.

	              *     y^2 = x^3 + a*x + b.

	              */

	int a_is_minus3; /* enable optimized point arithmetics for special case */
@@ -197,7 +197,7 @@ int ec_GFp_simple_add(const EC_GROUP *, EC_POINT *r, const EC_POINT *a, const EC 
int ec_GFp_simple_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a, BN_CTX *);

int ec_GFp_simple_is_at_infinity(const EC_GROUP *, const EC_POINT *);

int ec_GFp_simple_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);

int ec_GFp_simple_make_affine(const EC_GROUP *, const EC_POINT *, BN_CTX *);

int ec_GFp_simple_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);

int ec_GFp_simple_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *);

int ec_GFp_simple_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);

crypto/ec/ec_lib.c

+1 −1
Original line number Diff line number Diff line
@@ -421,7 +421,7 @@ int EC_POINT_is_on_curve(const EC_GROUP *group, const EC_POINT *point, BN_CTX *c 
	}





int EC_POINT_make_affine(const EC_GROUP *group, const EC_POINT *point, BN_CTX *ctx)

int EC_POINT_make_affine(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx)

	{

	if (group->meth->make_affine == 0)

		{

crypto/ec/ecp_smpl.c

+161 −7
Original line number Diff line number Diff line
@@ -385,8 +385,8 @@ int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, con 
			{

			/* a is the same point as b */

			BN_CTX_end(ctx);

			ctx = NULL;

			ret = EC_POINT_dbl(group, r, a, ctx);

			ctx = NULL;

			goto end;

			}

		else
@@ -491,8 +491,6 @@ int ec_GFp_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, BN_ 
	n3 = BN_CTX_get(ctx);

	if (n3 == NULL) goto err;



	/* TODO: optimization for group->a_is_minus3 */



	/* n1 */

	if (a->Z_is_one)

		{
@@ -577,12 +575,168 @@ int ec_GFp_simple_is_at_infinity(const EC_GROUP *group, const EC_POINT *point) 
	}





int ec_GFp_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point, BN_CTX *ctx);

/* TODO */

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, *tmp1, *tmp2, *Z4, *Z6;

	int ret = -1;



	if (EC_POINT_is_at_infinity(group, point))

		return 1;

	

int ec_GFp_simple_make_affine(const EC_GROUP *group, const EC_POINT *point, BN_CTX *ctx);

/* TODO */

	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);



	rh = BN_CTX_get(ctx);

	tmp1 = BN_CTX_get(ctx);

	tmp2 = 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^3 */

	if (!field_sqr(group, rh, &point->X, ctx)) goto err;

	if (!field_mul(group, rh, rh, &point->X, ctx)) goto err;



	if (!point->Z_is_one)

		{

		if (!field_sqr(group, tmp1, &point->Z, ctx)) goto err;

		if (!field_sqr(group, Z4, tmp1, ctx)) goto err;

		if (!field_mul(group, Z6, Z4, tmp1, ctx)) goto err;



		/* rh := rh + a*X*Z^4 */

		if (!field_mul(group, tmp1, &point->X, Z4, ctx)) goto err;

		if (&group->a_is_minus3)

			{

			if (!BN_mod_lshift1_quick(tmp2, tmp1, p)) goto err;

			if (!BN_mod_add_quick(tmp2, tmp2, tmp1, p)) goto err;

			if (!BN_mod_sub_quick(rh, rh, tmp2, p)) goto err;

			}

		else

			{

			if (!field_mul(group, tmp2, tmp1, &group->a, ctx)) goto err;

			if (!BN_mod_add_quick(rh, rh, tmp2, p)) goto err;

			}



		/* rh := rh + b*Z^6 */

		if (!field_mul(group, tmp1, &group->b, Z6, ctx)) goto err;

		if (!BN_mod_add_quick(rh, rh, tmp1, p)) goto err;

		}

	else

		{

		/* point->Z_is_one */



		/* rh := rh + a*X */

		if (&group->a_is_minus3)

			{

			if (!BN_mod_lshift1_quick(tmp2, &point->X, p)) goto err;

			if (!BN_mod_add_quick(tmp2, tmp2, &point->X, p)) goto err;

			if (!BN_mod_sub_quick(rh, rh, tmp2, p)) goto err;

			}

		else

			{

			if (!field_mul(group, tmp2, &point->X, &group->a, ctx)) goto err;

			if (!BN_mod_add_quick(rh, rh, tmp2, p)) goto err;

			}



		/* rh := rh + b */

		if (!BN_mod_add_quick(rh, rh, &group->b, p)) goto err;

		}



	/* 'lh' := Y^2 */

	if (!field_sqr(group, tmp1, &point->Y, ctx)) goto err;



	ret = (0 == BN_cmp(tmp1, rh));



 err:

	BN_CTX_end(ctx);

	if (new_ctx != NULL)

		BN_CTX_free(new_ctx);

	return ret;

	}





int ec_GFp_simple_make_affine(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx)

	{

	BN_CTX *new_ctx = NULL;

	BIGNUM *Z, *Z_1, *Z_2, *Z_3;

	int ret = 0;



	if (point->Z_is_one || EC_POINT_is_at_infinity(group, point))

		return 1;



	if (ctx == NULL)

		{

		ctx = new_ctx = BN_CTX_new();

		if (ctx == NULL)

			return 0;

		}

	BN_CTX_start(ctx);



	Z = BN_CTX_get(ctx);

	Z_1 = BN_CTX_get(ctx);

	Z_2 = BN_CTX_get(ctx);

	Z_3 = BN_CTX_get(ctx);

	if (Z_3 == NULL) goto end;



	/* transform  (X, Y, Z)  into  (X/Z^2, Y/Z^3, 1) */

	

	if (group->meth->field_decode)

		{

		if (!group->meth->field_decode(group, Z, &point->Z, ctx)) goto end;

		}

	else

		Z = &point->Z;

	

	if (BN_is_one(Z))

		{

		point->Z_is_one = 1;

		ret = 1;

		goto end;

		}



	if (!BN_mod_inverse(Z_1, Z, &group->field, ctx))

		{

		ECerr(EC_F_EC_GFP_SIMPLE_MAKE_AFFINE, ERR_R_BN_LIB);

		goto end;

		}

	if (!BN_mod_sqr(Z_2, Z_1, &group->field, ctx)) goto end;

	if (!BN_mod_mul(Z_3, Z_2, Z_1, &group->field, ctx)) goto end;

	

	if (!BN_mod_mul(&point->X, &point->X, Z_2, &group->field, ctx)) goto end;

	if (!BN_mod_mul(&point->Y, &point->Y, Z_2, &group->field, ctx)) goto end;

	if (!BN_set_word(&point->Z, 1)) goto end;

	point->Z_is_one = 1;



	ret = 1;



 end:

	BN_CTX_end(ctx);

	if (new_ctx != NULL)

		BN_CTX_free(new_ctx);

	return ret;

	}





int ec_GFp_simple_field_mul(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)