From c9aad1ae6227c434d480d1d3aa8eae3c3c910c18 Mon Sep 17 00:00:00 2001 From: marha Date: Sun, 22 Feb 2015 14:43:31 +0100 Subject: Upgraded to openssl-1.0.2 --- openssl/doc/crypto/EC_POINT_new.pod | 123 ++++++++++++++++++++++++++++++++++++ 1 file changed, 123 insertions(+) create mode 100755 openssl/doc/crypto/EC_POINT_new.pod (limited to 'openssl/doc/crypto/EC_POINT_new.pod') diff --git a/openssl/doc/crypto/EC_POINT_new.pod b/openssl/doc/crypto/EC_POINT_new.pod new file mode 100755 index 000000000..69eb0d1a0 --- /dev/null +++ b/openssl/doc/crypto/EC_POINT_new.pod @@ -0,0 +1,123 @@ +=pod + +=head1 NAME + +EC_POINT_new, EC_POINT_free, EC_POINT_clear_free, EC_POINT_copy, EC_POINT_dup, EC_POINT_method_of, EC_POINT_set_to_infinity, EC_POINT_set_Jprojective_coordinates, EC_POINT_get_Jprojective_coordinates_GFp, EC_POINT_set_affine_coordinates_GFp, EC_POINT_get_affine_coordinates_GFp, EC_POINT_set_compressed_coordinates_GFp, EC_POINT_set_affine_coordinates_GF2m, EC_POINT_get_affine_coordinates_GF2m, EC_POINT_set_compressed_coordinates_GF2m, EC_POINT_point2oct, EC_POINT_oct2point, EC_POINT_point2bn, EC_POINT_bn2point, EC_POINT_point2hex, EC_POINT_hex2point - Functions for creating, destroying and manipulating B objects. + +=head1 SYNOPSIS + + #include + #include + + EC_POINT *EC_POINT_new(const EC_GROUP *group); + void EC_POINT_free(EC_POINT *point); + void EC_POINT_clear_free(EC_POINT *point); + int EC_POINT_copy(EC_POINT *dst, const EC_POINT *src); + EC_POINT *EC_POINT_dup(const EC_POINT *src, const EC_GROUP *group); + const EC_METHOD *EC_POINT_method_of(const EC_POINT *point); + int EC_POINT_set_to_infinity(const EC_GROUP *group, EC_POINT *point); + int EC_POINT_set_Jprojective_coordinates_GFp(const EC_GROUP *group, EC_POINT *p, + const BIGNUM *x, const BIGNUM *y, const BIGNUM *z, BN_CTX *ctx); + int EC_POINT_get_Jprojective_coordinates_GFp(const EC_GROUP *group, + const EC_POINT *p, BIGNUM *x, BIGNUM *y, BIGNUM *z, BN_CTX *ctx); + int EC_POINT_set_affine_coordinates_GFp(const EC_GROUP *group, EC_POINT *p, + const BIGNUM *x, const BIGNUM *y, BN_CTX *ctx); + int EC_POINT_get_affine_coordinates_GFp(const EC_GROUP *group, + const EC_POINT *p, BIGNUM *x, BIGNUM *y, BN_CTX *ctx); + int EC_POINT_set_compressed_coordinates_GFp(const EC_GROUP *group, EC_POINT *p, + const BIGNUM *x, int y_bit, BN_CTX *ctx); + int EC_POINT_set_affine_coordinates_GF2m(const EC_GROUP *group, EC_POINT *p, + const BIGNUM *x, const BIGNUM *y, BN_CTX *ctx); + int EC_POINT_get_affine_coordinates_GF2m(const EC_GROUP *group, + const EC_POINT *p, BIGNUM *x, BIGNUM *y, BN_CTX *ctx); + int EC_POINT_set_compressed_coordinates_GF2m(const EC_GROUP *group, EC_POINT *p, + const BIGNUM *x, int y_bit, BN_CTX *ctx); + size_t EC_POINT_point2oct(const EC_GROUP *group, const EC_POINT *p, + point_conversion_form_t form, + unsigned char *buf, size_t len, BN_CTX *ctx); + int EC_POINT_oct2point(const EC_GROUP *group, EC_POINT *p, + const unsigned char *buf, size_t len, BN_CTX *ctx); + BIGNUM *EC_POINT_point2bn(const EC_GROUP *, const EC_POINT *, + point_conversion_form_t form, BIGNUM *, BN_CTX *); + EC_POINT *EC_POINT_bn2point(const EC_GROUP *, const BIGNUM *, + EC_POINT *, BN_CTX *); + char *EC_POINT_point2hex(const EC_GROUP *, const EC_POINT *, + point_conversion_form_t form, BN_CTX *); + EC_POINT *EC_POINT_hex2point(const EC_GROUP *, const char *, + EC_POINT *, BN_CTX *); + + +=head1 DESCRIPTION + +An EC_POINT represents a point on a curve. A new point is constructed by calling the function EC_POINT_new and providing the B +object that the point relates to. + +EC_POINT_free frees the memory associated with the EC_POINT. + +EC_POINT_clear_free destroys any sensitive data held within the EC_POINT and then frees its memory. + +EC_POINT_copy copies the point B into B. Both B and B must use the same EC_METHOD. + +EC_POINT_dup creates a new EC_POINT object and copies the content from B to the newly created +EC_POINT object. + +EC_POINT_method_of obtains the EC_METHOD associated with B. + +A valid point on a curve is the special point at infinity. A point is set to be at infinity by calling EC_POINT_set_to_infinity. + +The affine co-ordinates for a point describe a point in terms of its x and y position. The functions +EC_POINT_set_affine_coordinates_GFp and EC_POINT_set_affine_coordinates_GF2m set the B and B co-ordinates for the point +B

defined over the curve given in B. + +As well as the affine co-ordinates, a point can alternatively be described in terms of its Jacobian +projective co-ordinates (for Fp curves only). Jacobian projective co-ordinates are expressed as three values x, y and z. Working in +this co-ordinate system provides more efficient point multiplication operations. +A mapping exists between Jacobian projective co-ordinates and affine co-ordinates. A Jacobian projective co-ordinate (x, y, z) can be written as an affine co-ordinate as (x/(z^2), y/(z^3)). Conversion to Jacobian projective to affine co-ordinates is simple. The co-ordinate (x, y) is +mapped to (x, y, 1). To set or get the projective co-ordinates use EC_POINT_set_Jprojective_coordinates_GFp and +EC_POINT_get_Jprojective_coordinates_GFp respectively. + +Points can also be described in terms of their compressed co-ordinates. For a point (x, y), for any given value for x such that the point is +on the curve there will only ever be two possible values for y. Therefore a point can be set using the EC_POINT_set_compressed_coordinates_GFp +and EC_POINT_set_compressed_coordinates_GF2m functions where B is the x co-ordinate and B is a value 0 or 1 to identify which of +the two possible values for y should be used. + +In addition EC_POINTs can be converted to and from various external representations. Supported representations are octet strings, BIGNUMs and hexadecimal. The format of the external representation is described by the point_conversion_form. See L for +a description of point_conversion_form. Octet strings are stored in a buffer along with an associated buffer length. A point held in a BIGNUM is calculated by converting the point to an octet string and then converting that octet string into a BIGNUM integer. Points in hexadecimal format are stored in a NULL terminated character string where each character is one of the printable values 0-9 or A-F (or a-f). + +The functions EC_POINT_point2oct, EC_POINT_oct2point, EC_POINT_point2bn, EC_POINT_bn2point, EC_POINT_point2hex and EC_POINT_hex2point convert +from and to EC_POINTs for the formats: octet string, BIGNUM and hexadecimal respectively. + +The function EC_POINT_point2oct must be supplied with a buffer long enough to store the octet string. The return value provides the number of +octets stored. Calling the function with a NULL buffer will not perform the conversion but will still return the required buffer length. + +The function EC_POINT_point2hex will allocate sufficient memory to store the hexadecimal string. It is the caller's responsibility to free +this memory with a subsequent call to OPENSSL_free(). + +=head1 RETURN VALUES + +EC_POINT_new and EC_POINT_dup return the newly allocated EC_POINT or NULL on error. + +The following functions return 1 on success or 0 on error: EC_POINT_copy, EC_POINT_set_to_infinity, EC_POINT_set_Jprojective_coordinates_GFp, +EC_POINT_get_Jprojective_coordinates_GFp, EC_POINT_set_affine_coordinates_GFp, EC_POINT_get_affine_coordinates_GFp, +EC_POINT_set_compressed_coordinates_GFp, EC_POINT_set_affine_coordinates_GF2m, EC_POINT_get_affine_coordinates_GF2m, +EC_POINT_set_compressed_coordinates_GF2m and EC_POINT_oct2point. + +EC_POINT_method_of returns the EC_METHOD associated with the supplied EC_POINT. + +EC_POINT_point2oct returns the length of the required buffer, or 0 on error. + +EC_POINT_point2bn returns the pointer to the BIGNUM supplied, or NULL on error. + +EC_POINT_bn2point returns the pointer to the EC_POINT supplied, or NULL on error. + +EC_POINT_point2hex returns a pointer to the hex string, or NULL on error. + +EC_POINT_hex2point returns the pointer to the EC_POINT supplied, or NULL on error. + +=head1 SEE ALSO + +L, L, L, L, +L, L, +L, L + +=cut -- cgit v1.2.3