X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fec%2Fec2_mult.c;h=f41665ac10bcbb8bc3065710506f7c97ed7a7854;hp=a0effa95ad8ba93b95ba3d94afb8a95536bb8576;hb=7eef2b0cd712d987b0bd556ad8ec637332ff32fb;hpb=37c660ff9b22d6f0eb19a9881d3b663ca4f63449 diff --git a/crypto/ec/ec2_mult.c b/crypto/ec/ec2_mult.c index a0effa95ad..f41665ac10 100644 --- a/crypto/ec/ec2_mult.c +++ b/crypto/ec/ec2_mult.c @@ -67,16 +67,20 @@ * */ +#define OPENSSL_FIPSAPI + #include #include "ec_lcl.h" +#ifndef OPENSSL_NO_EC2M + /* Compute the x-coordinate x/z for the point 2*(x/z) in Montgomery projective * coordinates. * Uses algorithm Mdouble in appendix of * Lopez, J. and Dahab, R. "Fast multiplication on elliptic curves over - * GF(2^m) without precomputation". + * GF(2^m) without precomputation" (CHES '99, LNCS 1717). * modified to not require precomputation of c=b^{2^{m-1}}. */ static int gf2m_Mdouble(const EC_GROUP *group, BIGNUM *x, BIGNUM *z, BN_CTX *ctx) @@ -107,8 +111,8 @@ static int gf2m_Mdouble(const EC_GROUP *group, BIGNUM *x, BIGNUM *z, BN_CTX *ctx /* Compute the x-coordinate x1/z1 for the point (x1/z1)+(x2/x2) in Montgomery * projective coordinates. * Uses algorithm Madd in appendix of - * Lopex, J. and Dahab, R. "Fast multiplication on elliptic curves over - * GF(2^m) without precomputation". + * Lopez, J. and Dahab, R. "Fast multiplication on elliptic curves over + * GF(2^m) without precomputation" (CHES '99, LNCS 1717). */ static int gf2m_Madd(const EC_GROUP *group, const BIGNUM *x, BIGNUM *x1, BIGNUM *z1, const BIGNUM *x2, const BIGNUM *z2, BN_CTX *ctx) @@ -140,8 +144,8 @@ static int gf2m_Madd(const EC_GROUP *group, const BIGNUM *x, BIGNUM *x1, BIGNUM /* Compute the x, y affine coordinates from the point (x1, z1) (x2, z2) * using Montgomery point multiplication algorithm Mxy() in appendix of - * Lopex, J. and Dahab, R. "Fast multiplication on elliptic curves over - * GF(2^m) without precomputation". + * 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 @@ -155,8 +159,8 @@ static int gf2m_Mxy(const EC_GROUP *group, const BIGNUM *x, const BIGNUM *y, BIG if (BN_is_zero(z1)) { - if (!BN_zero(x2)) return 0; - if (!BN_zero(z2)) return 0; + BN_zero(x2); + BN_zero(z2); return 1; } @@ -209,19 +213,19 @@ static int gf2m_Mxy(const EC_GROUP *group, const BIGNUM *x, const BIGNUM *y, BIG /* Computes scalar*point and stores the result in r. * point can not equal r. * Uses algorithm 2P of - * Lopex, J. and Dahab, R. "Fast multiplication on elliptic curves over - * GF(2^m) without precomputation". + * Lopez, J. and Dahab, R. "Fast multiplication on elliptic curves over + * GF(2^m) without precomputation" (CHES '99, LNCS 1717). */ 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, j; - BN_ULONG mask; + int ret = 0, i; + BN_ULONG mask,word; if (r == point) { - ECerr(EC_F_EC_POINT_MUL, EC_R_INVALID_ARGUMENT); + ECerr(EC_F_EC_GF2M_MONTGOMERY_POINT_MULTIPLY, EC_R_INVALID_ARGUMENT); return 0; } @@ -251,22 +255,24 @@ static int ec_GF2m_montgomery_point_multiply(const EC_GROUP *group, EC_POINT *r, 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; j = BN_BITS2 - 1; + i = scalar->top - 1; mask = BN_TBIT; - while (!(scalar->d[i] & mask)) { mask >>= 1; j--; } - mask >>= 1; j--; + 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--; j = BN_BITS2 - 1; + i--; mask = BN_TBIT; } for (; i >= 0; i--) { - for (; j >= 0; j--) + word = scalar->d[i]; + while (mask) { - if (scalar->d[i] & mask) + if (word & mask) { if (!gf2m_Madd(group, &point->X, x1, z1, x2, z2, ctx)) goto err; if (!gf2m_Mdouble(group, x2, z2, ctx)) goto err; @@ -278,7 +284,6 @@ static int ec_GF2m_montgomery_point_multiply(const EC_GROUP *group, EC_POINT *r, } mask >>= 1; } - j = BN_BITS2 - 1; mask = BN_TBIT; } @@ -296,8 +301,8 @@ static int ec_GF2m_montgomery_point_multiply(const EC_GROUP *group, EC_POINT *r, } /* GF(2^m) field elements should always have BIGNUM::neg = 0 */ - BN_set_sign(&r->X, 0); - BN_set_sign(&r->Y, 0); + BN_set_negative(&r->X, 0); + BN_set_negative(&r->Y, 0); ret = 1; @@ -315,8 +320,10 @@ int ec_GF2m_simple_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar, size_t num, const EC_POINT *points[], const BIGNUM *scalars[], BN_CTX *ctx) { BN_CTX *new_ctx = NULL; - int ret = 0, i; + int ret = 0; + size_t i; EC_POINT *p=NULL; + EC_POINT *acc = NULL; if (ctx == NULL) { @@ -336,29 +343,33 @@ int ec_GF2m_simple_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar, } if ((p = EC_POINT_new(group)) == NULL) goto err; + if ((acc = EC_POINT_new(group)) == NULL) goto err; - if (!EC_POINT_set_to_infinity(group, r)) goto err; + if (!EC_POINT_set_to_infinity(group, acc)) goto err; if (scalar) { if (!ec_GF2m_montgomery_point_multiply(group, p, scalar, group->generator, ctx)) goto err; - if (BN_get_sign(scalar)) + if (BN_is_negative(scalar)) if (!group->meth->invert(group, p, ctx)) goto err; - if (!group->meth->add(group, r, r, p, ctx)) goto err; + if (!group->meth->add(group, acc, acc, p, ctx)) goto err; } for (i = 0; i < num; i++) { if (!ec_GF2m_montgomery_point_multiply(group, p, scalars[i], points[i], ctx)) goto err; - if (BN_get_sign(scalars[i])) + if (BN_is_negative(scalars[i])) if (!group->meth->invert(group, p, ctx)) goto err; - if (!group->meth->add(group, r, r, p, ctx)) goto err; + if (!group->meth->add(group, acc, acc, p, ctx)) goto err; } + if (!EC_POINT_copy(r, acc)) goto err; + ret = 1; err: if (p) EC_POINT_free(p); + if (acc) EC_POINT_free(acc); if (new_ctx != NULL) BN_CTX_free(new_ctx); return ret; @@ -377,3 +388,5 @@ int ec_GF2m_have_precompute_mult(const EC_GROUP *group) { return ec_wNAF_have_precompute_mult(group); } + +#endif