1.\" $OpenBSD: DH_new.3,v 1.4 2016/12/10 22:30:54 schwarze Exp $ 2.\" OpenSSL b97fdb57 Nov 11 09:33:09 2016 +0100 3.\" 4.\" This file was written by Ulf Moeller <ulf@openssl.org>. 5.\" Copyright (c) 2000 The OpenSSL Project. All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in 16.\" the documentation and/or other materials provided with the 17.\" distribution. 18.\" 19.\" 3. All advertising materials mentioning features or use of this 20.\" software must display the following acknowledgment: 21.\" "This product includes software developed by the OpenSSL Project 22.\" for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 23.\" 24.\" 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 25.\" endorse or promote products derived from this software without 26.\" prior written permission. For written permission, please contact 27.\" openssl-core@openssl.org. 28.\" 29.\" 5. Products derived from this software may not be called "OpenSSL" 30.\" nor may "OpenSSL" appear in their names without prior written 31.\" permission of the OpenSSL Project. 32.\" 33.\" 6. Redistributions of any form whatsoever must retain the following 34.\" acknowledgment: 35.\" "This product includes software developed by the OpenSSL Project 36.\" for use in the OpenSSL Toolkit (http://www.openssl.org/)" 37.\" 38.\" THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 39.\" EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 40.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 41.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 42.\" ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 43.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 44.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 45.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 46.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 47.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 48.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 49.\" OF THE POSSIBILITY OF SUCH DAMAGE. 50.\" 51.Dd $Mdocdate: December 10 2016 $ 52.Dt DH_NEW 3 53.Os 54.Sh NAME 55.Nm DH_new , 56.Nm DH_free 57.Nd allocate and free DH objects 58.Sh SYNOPSIS 59.In openssl/dh.h 60.Ft DH* 61.Fn DH_new void 62.Ft void 63.Fo DH_free 64.Fa "DH *dh" 65.Fc 66.Sh DESCRIPTION 67The DH functions implement the Diffie-Hellman key agreement protocol. 68.Pp 69.Fn DH_new 70allocates and initializes a 71.Vt DH 72structure. 73.Pp 74.Fn DH_free 75frees the 76.Vt DH 77structure and its components. 78The values are erased before the memory is returned to the system. 79If 80.Fa dh 81is a 82.Dv NULL 83pointer, no action occurs. 84.Sh RETURN VALUES 85If the allocation fails, 86.Fn DH_new 87returns 88.Dv NULL 89and sets an error code that can be obtained by 90.Xr ERR_get_error 3 . 91Otherwise it returns a pointer to the newly allocated structure. 92.Sh SEE ALSO 93.Xr BN_new 3 , 94.Xr d2i_DHparams 3 , 95.Xr DH_generate_key 3 , 96.Xr DH_generate_parameters 3 , 97.Xr DH_get_ex_new_index 3 , 98.Xr DH_set_method 3 , 99.Xr DH_size 3 , 100.Xr DHparams_print 3 , 101.Xr DSA_dup_DH 3 , 102.Xr ERR_get_error 3 103.Sh HISTORY 104.Fn DH_new 105and 106.Fn DH_free 107are available in all versions of SSLeay and OpenSSL. 108