EC_POINT_add(3) LibreSSL 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);
DESCRIPTIONEC_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.
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 ALSOcrypto(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)LibreSSL 2015-12-05 EC_POINT_add(3)
