DH_SET_METHOD(3ossl) OpenSSL DH_SET_METHOD(3ossl)
NAME
DH_set_default_method, DH_get_default_method, DH_set_method,
DH_new_method, DH_OpenSSL - select DH method
SYNOPSIS
#include <openssl/dh.h>
The following functions have been deprecated since OpenSSL 3.0, and can
be hidden entirely by defining OPENSSL_API_COMPAT with a suitable
version value, see openssl_user_macros(7):
void DH_set_default_method(const DH_METHOD *meth);
const DH_METHOD *DH_get_default_method(void);
int DH_set_method(DH *dh, const DH_METHOD *meth);
DH *DH_new_method(ENGINE *engine);
const DH_METHOD *DH_OpenSSL(void);
DESCRIPTION
All of the functions described on this page are deprecated.
Applications should instead use the provider APIs.
A DH_METHOD specifies the functions that OpenSSL uses for
Diffie-Hellman operations. By modifying the method, alternative
implementations such as hardware accelerators may be used. IMPORTANT:
See the NOTES section for important information about how these DH API
functions are affected by the use of ENGINE API calls.
Initially, the default DH_METHOD is the OpenSSL internal
implementation, as returned by DH_OpenSSL().
DH_set_default_method() makes meth the default method for all DH
structures created later. NB: This is true only whilst no ENGINE has
been set as a default for DH, so this function is no longer
recommended. This function is not thread-safe and should not be called
at the same time as other OpenSSL functions.
DH_get_default_method() returns a pointer to the current default
DH_METHOD. However, the meaningfulness of this result is dependent on
whether the ENGINE API is being used, so this function is no longer
recommended.
DH_set_method(3) selects meth to perform all operations using the key
dh. This will replace the DH_METHOD used by the DH key and if the
previous method was supplied by an ENGINE, the handle to that ENGINE
will be released during the change. It is possible to have DH keys that
only work with certain DH_METHOD implementations (e.g. from an ENGINE
module that supports embedded hardware-protected keys), and in such
cases attempting to change the DH_METHOD for the key can have
unexpected results.
DH_new_method() allocates and initializes a DH structure so that engine
will be used for the DH operations. If engine is NULL, the default
ENGINE for DH operations is used, and if no default ENGINE is set, the
DH_METHOD controlled by DH_set_default_method() is used.
A new DH_METHOD object may be constructed using DH_meth_new() (see
DH_meth_new(3)).
RETURN VALUES
DH_OpenSSL() and DH_get_default_method() return pointers to the
respective DH_METHODs.
DH_set_default_method() returns no value.
DH_set_method(3) returns nonzero if the provided meth was successfully
set as the method for dh (including unloading the ENGINE handle if the
previous method was supplied by an ENGINE).
DH_new_method() returns NULL and sets an error code that can be
obtained by ERR_get_error(3) if the allocation fails. Otherwise it
returns a pointer to the newly allocated structure.
SEE ALSO
DH_new(3), DH_new(3), DH_meth_new(3)
HISTORY
All of these functions were deprecated in OpenSSL 3.0.
COPYRIGHT
Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file LICENSE in the source distribution or at
<https://www.openssl.org/source/license.html>.
3.3.2 2024-09-04 DH_SET_METHOD(3ossl)
openssl 3.3.2 - Generated Sun Sep 8 15:59:03 CDT 2024