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DH_SET_METHOD(3)		    OpenSSL		      DH_SET_METHOD(3)

       DH_set_default_method, DH_get_default_method, DH_set_method,
       DH_new_method, DH_OpenSSL - select DH method

	#include <openssl/dh.h>

	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);

       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

       DH_set_method() 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_OpenSSL() and	DH_get_default_method()	return pointers	to the
       respective DH_METHODs.

       DH_set_default_method() returns no value.

       DH_set_method() 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.

       DH_new(3), DH_new(3), DH_meth_new(3)

       Copyright 2000-2020 The OpenSSL Project Authors.	All Rights Reserved.

       Licensed	under the OpenSSL license (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

1.1.1h				  2020-09-22		      DH_SET_METHOD(3)


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