src/lib/libcrypto/man/EC_KEY_METHOD_new.3

320 lines
8 KiB
Groff

.\" $OpenBSD: EC_KEY_METHOD_new.3,v 1.4 2024/07/21 08:36:43 tb Exp $
.\" Copyright (c) 2019 Ingo Schwarze <schwarze@openbsd.org>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd $Mdocdate: July 21 2024 $
.Dt EC_KEY_METHOD_NEW 3
.Os
.Sh NAME
.Nm EC_KEY_METHOD_new ,
.Nm EC_KEY_METHOD_free ,
.Nm EC_KEY_METHOD_set_init ,
.Nm EC_KEY_METHOD_get_init ,
.Nm EC_KEY_METHOD_set_sign ,
.Nm EC_KEY_METHOD_get_sign ,
.Nm EC_KEY_METHOD_set_verify ,
.Nm EC_KEY_METHOD_get_verify ,
.Nm EC_KEY_METHOD_set_keygen ,
.Nm EC_KEY_METHOD_get_keygen ,
.Nm EC_KEY_METHOD_set_compute_key ,
.Nm EC_KEY_METHOD_get_compute_key ,
.Nm EC_KEY_OpenSSL ,
.Nm EC_KEY_set_default_method ,
.Nm EC_KEY_get_default_method ,
.Nm EC_KEY_new_method ,
.Nm EC_KEY_set_method ,
.Nm EC_KEY_get_method
.Nd custom EC_KEY implementations
.Sh SYNOPSIS
.In openssl/ec.h
.Ft EC_KEY_METHOD *
.Fo EC_KEY_METHOD_new
.Fa "const EC_KEY_METHOD *meth"
.Fc
.Ft void
.Fo EC_KEY_METHOD_free
.Fa "EC_KEY_METHOD *meth"
.Fc
.Ft void
.Fo EC_KEY_METHOD_set_init
.Fa "EC_KEY_METHOD *meth"
.Fa "int (*init)(EC_KEY *key)"
.Fa "void (*finish)(EC_KEY *key)"
.Fa "int (*copy)(EC_KEY *dest, const EC_KEY *src)"
.Fa "int (*set_group)(EC_KEY *key, const EC_GROUP *grp)"
.Fa "int (*set_private)(EC_KEY *key, const BIGNUM *priv_key)"
.Fa "int (*set_public)(EC_KEY *key, const EC_POINT *pub_key)"
.Fc
.Ft void
.Fo EC_KEY_METHOD_get_init
.Fa "const EC_KEY_METHOD *meth"
.Fa "int (**pinit)(EC_KEY *key)"
.Fa "void (**pfinish)(EC_KEY *key)"
.Fa "int (**pcopy)(EC_KEY *dest, const EC_KEY *src)"
.Fa "int (**pset_group)(EC_KEY *key, const EC_GROUP *grp)"
.Fa "int (**pset_private)(EC_KEY *key, const BIGNUM *priv_key)"
.Fa "int (**pset_public)(EC_KEY *key, const EC_POINT *pub_key)"
.Fc
.Ft void
.Fo EC_KEY_METHOD_set_sign
.Fa "EC_KEY_METHOD *meth"
.Fa "int (*sign)(int type, const unsigned char *dgst, int dgstlen,\
unsigned char *sig, unsigned int *siglen,\
const BIGNUM *kinv, const BIGNUM *r, EC_KEY *eckey)"
.Fa "int (*sign_setup)(EC_KEY *eckey, BN_CTX *ctx,\
BIGNUM **kinv, BIGNUM **rp)"
.Fa "ECDSA_SIG *(*sign_sig)(const unsigned char *dgst, int dgstlen,\
const BIGNUM *kinv, const BIGNUM *rp, EC_KEY *eckey)"
.Fc
.Ft void
.Fo EC_KEY_METHOD_get_sign
.Fa "const EC_KEY_METHOD *meth"
.Fa "int (**psign)(int type, const unsigned char *dgst, int dgstlen,\
unsigned char *sig, unsigned int *siglen,\
const BIGNUM *kinv, const BIGNUM *r, EC_KEY *eckey)"
.Fa "int (**psign_setup)(EC_KEY *eckey, BN_CTX *ctx,\
BIGNUM **kinv, BIGNUM **rp)"
.Fa "ECDSA_SIG *(**psign_sig)(const unsigned char *dgst, int dgstlen,\
const BIGNUM *kinv, const BIGNUM *rp, EC_KEY *eckey)"
.Fc
.Ft void
.Fo EC_KEY_METHOD_set_verify
.Fa "EC_KEY_METHOD *meth"
.Fa "int (*verify)(int type, const unsigned char *dgst, int dgst_len,\
const unsigned char *sigbuf, int sig_len, EC_KEY *eckey)"
.Fa "int (*verify_sig)(const unsigned char *dgst, int dgst_len,\
const ECDSA_SIG *sig, EC_KEY *eckey)"
.Fc
.Ft void
.Fo EC_KEY_METHOD_get_verify
.Fa "const EC_KEY_METHOD *meth"
.Fa "int (**pverify)(int type, const unsigned char *dgst, int dgst_len,\
const unsigned char *sigbuf, int sig_len, EC_KEY *eckey)"
.Fa "int (**pverify_sig)(const unsigned char *dgst, int dgst_len,\
const ECDSA_SIG *sig, EC_KEY *eckey)"
.Fc
.Ft void
.Fo EC_KEY_METHOD_set_keygen
.Fa "EC_KEY_METHOD *meth"
.Fa "int (*keygen)(EC_KEY *key)"
.Fc
.Ft void
.Fo EC_KEY_METHOD_get_keygen
.Fa "const EC_KEY_METHOD *meth"
.Fa "int (**pkeygen)(EC_KEY *key)"
.Fc
.Ft void
.Fo EC_KEY_METHOD_set_compute_key
.Fa "EC_KEY_METHOD *meth"
.Fa "int (*ckey)(void *out, size_t outlen,\
const EC_POINT *pub_key, EC_KEY *ecdh,\
void *(*KDF) (const void *in, size_t inlen, void *out, size_t *outlen))"
.Fc
.Ft void
.Fo EC_KEY_METHOD_get_compute_key
.Fa "const EC_KEY_METHOD *meth"
.Fa "int (**pck)(void *out, size_t outlen,\
const EC_POINT *pub_key, EC_KEY *ecdh,\
void *(*KDF) (const void *in, size_t inlen, void *out, size_t *outlen))"
.Fc
.Ft const EC_KEY_METHOD *
.Fn EC_KEY_OpenSSL void
.Ft void
.Fo EC_KEY_set_default_method
.Fa "const EC_KEY_METHOD *meth"
.Fc
.Ft const EC_KEY_METHOD *
.Fn EC_KEY_get_default_method void
.Ft EC_KEY *
.Fo EC_KEY_new_method
.Fa "ENGINE *engine"
.Fc
.Ft int
.Fo EC_KEY_set_method
.Fa "EC_KEY *key"
.Fa "const EC_KEY_METHOD *meth"
.Fc
.Ft const EC_KEY_METHOD *
.Fo EC_KEY_get_method
.Fa "const EC_KEY *key"
.Fc
.Sh DESCRIPTION
An
.Vt EC_KEY_METHOD
object holds function pointers used for
.Vt EC_KEY
operations.
.Pp
.Fn EC_KEY_METHOD_new
creates a shallow copy of
.Fa meth ,
or an empty
.Vt EC_KEY_METHOD
object if
.Fa meth
is
.Dv NULL .
.Pp
.Fn EC_KEY_METHOD_free
frees
.Fa meth .
If
.Fa meth
is
.Dv NULL
or the return value of
.Fn EC_KEY_OpenSSL ,
no action occurs.
.Pp
.Fn EC_KEY_METHOD_set_init
and
.Fn EC_KEY_METHOD_get_init
set and retrieve optional callback functions called at the following places:
.Pp
.Bl -tag -width set_private -compact
.It Fa init
at the end of
.Fn EC_KEY_new_method
and
.Fn EC_KEY_set_method
.It Fa finish
at the beginning of
.Xr EC_KEY_free 3 ,
.Xr EC_KEY_copy 3 ,
and
.Fn EC_KEY_set_method
.It Fa copy
at the end of
.Xr EC_KEY_copy 3
.It Fa set_group
at the end of
.Xr EC_KEY_set_group 3
and
.Xr EC_KEY_new_by_curve_name 3
.It Fa set_private
at the beginning of
.Xr EC_KEY_set_private_key 3
.It Fa set_public
at the beginning of
.Xr EC_KEY_set_public_key 3
.El
.Pp
If any of these callbacks returns 0, the calling function fails.
By default, all these callbacks are
.Dv NULL .
Arguments of
.Fn EC_KEY_METHOD_get_init
can be set to
.Dv NULL
to selectively retrieve callback function pointers.
.Pp
.Fn EC_KEY_METHOD_set_sign
and
.Fn EC_KEY_METHOD_get_sign
set and retrieve the functions implementing
.Xr ECDSA_sign 3
and
.Xr ECDSA_do_sign 3 .
.Pp
.Fn EC_KEY_METHOD_set_verify
and
.Fn EC_KEY_METHOD_get_verify
set and retrieve the functions implementing
.Xr ECDSA_verify 3
and
.Xr ECDSA_do_verify 3 .
.Pp
.Fn EC_KEY_METHOD_set_keygen
and
.Fn EC_KEY_METHOD_get_keygen
set and retrieve the function implementing
.Xr EC_KEY_generate_key 3 .
.Pp
.Fn EC_KEY_METHOD_set_compute_key
and
.Fn EC_KEY_METHOD_get_compute_key
set and retrieve the function implementing
.Xr ECDH_compute_key 3 .
.Pp
.Fn EC_KEY_set_default_method
chooses the
.Fa meth
to be used for the creation of new
.Vt EC_KEY
objects by future invocations of
.Fn EC_KEY_new_method ,
or reverts to the default implementation if
.Fa meth
is
.Dv NULL .
.Pp
.Fn EC_KEY_new_method
creates and initializes a new
.Vt EC_KEY
object using the
.Vt EC_KEY_METHOD
set with
.Fn EC_KEY_set_default_method .
The
.Fa ENGINE *engine
argument is always ignored and passing
.Dv NULL
is recommended.
.Pp
.Fn EC_KEY_set_method
dissociates the
.Fa key
from the
.Vt ENGINE
it is using, if any, and causes it to use
.Fa meth
in the future.
.Sh RETURN VALUES
.Fn EC_KEY_METHOD_new
returns the newly allocated
.Vt EC_KEY_METHOD
object or
.Dv NULL
if an error occurs.
.Pp
.Fn EC_KEY_OpenSSL
returns a static object representing the default EC_KEY implementation.
.Pp
.Fn EC_KEY_get_default_method
returns the
.Vt EC_KEY_METHOD
that
.Fn EC_KEY_new_method
will use for the creation of new
.Vt EC_KEY
objects in the future.
.Pp
.Fn EC_KEY_new_method
returns the newly allocated
.Vt EC_KEY
object or NULL if an error occurs.
.Pp
.Fn EC_KEY_set_method
returns 1 for success or 0 for failure.
.Pp
.Fn EC_KEY_get_method
returns the EC_KEY implementation used by the given
.Fa key .
.Sh SEE ALSO
.Xr EC_KEY_new 3 ,
.Xr ECDSA_sign 3
.Sh HISTORY
These functions first appeared in OpenSSL 1.1.0
and have been available since
.Ox 6.5 .