EC_POINT_invert(3)

EC_POINT_add(3)              OpenSSL              EC_POINT_add(3)

NAME

     EC_POINT_add, EC_POINT_dbl, EC_POINT_invert,
     EC_POINT_is_at_infinity, EC_POINT_is_on_curve, EC_POINT_cmp,
     EC_POINT_make_affine, EC_POINTs_make_affine, EC_POINTs_mul,
     EC_POINT_mul, EC_GROUP_precompute_mult,
     EC_GROUP_have_precompute_mult - Functions for performing
     mathematical operations and tests on EC_POINT objects.

SYNOPSIS

      #include <openssl/ec.h>
      #include <openssl/bn.h>

      int EC_POINT_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, const EC_POINT *b, BN_CTX *ctx);
      int EC_POINT_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, BN_CTX *ctx);
      int EC_POINT_invert(const EC_GROUP *group, EC_POINT *a, BN_CTX *ctx);
      int EC_POINT_is_at_infinity(const EC_GROUP *group, const EC_POINT *p);
      int EC_POINT_is_on_curve(const EC_GROUP *group, const EC_POINT *point, BN_CTX *ctx);
      int EC_POINT_cmp(const EC_GROUP *group, const EC_POINT *a, const EC_POINT *b, BN_CTX *ctx);
      int EC_POINT_make_affine(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx);
      int EC_POINTs_make_affine(const EC_GROUP *group, size_t num, EC_POINT *points[], BN_CTX *ctx);
      int EC_POINTs_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *n, size_t num, const EC_POINT *p[], const BIGNUM *m[], BN_CTX *ctx);
      int EC_POINT_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *n, const EC_POINT *q, const BIGNUM *m, BN_CTX *ctx);
      int EC_GROUP_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
      int EC_GROUP_have_precompute_mult(const EC_GROUP *group);

DESCRIPTION

     EC_POINT_add adds the two points a and b and places the
     result in r. Similarly EC_POINT_dbl doubles the point a and
     places the result in r. In both cases it is valid for r to
     be one of a or b.

     EC_POINT_invert calculates the inverse of the supplied point
     a. The result is placed back in a.

     The function EC_POINT_is_at_infinity tests whether the
     supplied point is at infinity or not.

     EC_POINT_is_on_curve tests whether the supplied point is on
     the curve or not.

     EC_POINT_cmp compares the two supplied points and tests
     whether or not they are equal.

     The functions EC_POINT_make_affine and EC_POINTs_make_affine
     force the internal representation of the EC_POINT(s) into
     the affine co-ordinate system. In the case of
     EC_POINTs_make_affine the value num provides the number of
     points in the array points to be forced.

     EC_POINT_mul calculates the value generator * n + q * m and
     stores the result in r. The value n may be NULL in which
     case the result is just q * m.

1.0.2t               Last change: 2019-09-10                    1

EC_POINT_add(3)              OpenSSL              EC_POINT_add(3)

     EC_POINTs_mul calculates the value generator * n + q[0] *
     m[0] + ... + q[num-1] * m[num-1]. As for EC_POINT_mul the
     value n may be NULL.

     The function EC_GROUP_precompute_mult stores multiples of
     the generator for faster point multiplication, whilst
     EC_GROUP_have_precompute_mult tests whether precomputation
     has already been done. See EC_GROUP_copy(3) for information
     about the generator.

RETURN VALUES

     The following functions return 1 on success or 0 on error:
     EC_POINT_add, EC_POINT_dbl, EC_POINT_invert,
     EC_POINT_make_affine, EC_POINTs_make_affine,
     EC_POINTs_make_affine, EC_POINT_mul, EC_POINTs_mul and
     EC_GROUP_precompute_mult.

     EC_POINT_is_at_infinity returns 1 if the point is at
     infinity, or 0 otherwise.

     EC_POINT_is_on_curve returns 1 if the point is on the curve,
     0 if not, or -1 on error.

     EC_POINT_cmp returns 1 if the points are not equal, 0 if
     they are, or -1 on error.

     EC_GROUP_have_precompute_mult return 1 if a precomputation
     has been done, or 0 if not.

SEE ALSO

     crypto(3), ec(3), EC_GROUP_new(3), EC_GROUP_copy(3),
     EC_POINT_new(3), EC_KEY_new(3), EC_GFp_simple_method(3),
     d2i_ECPKParameters(3)

1.0.2t               Last change: 2019-09-10                    2