1=pod 2 3=head1 NAME 4 5EVP_PKEY_CTX_new, EVP_PKEY_CTX_new_id, EVP_PKEY_CTX_dup, EVP_PKEY_CTX_free - public key algorithm context functions 6 7=head1 SYNOPSIS 8 9 #include <openssl/evp.h> 10 11 EVP_PKEY_CTX *EVP_PKEY_CTX_new(EVP_PKEY *pkey, ENGINE *e); 12 EVP_PKEY_CTX *EVP_PKEY_CTX_new_id(int id, ENGINE *e); 13 EVP_PKEY_CTX *EVP_PKEY_CTX_dup(EVP_PKEY_CTX *ctx); 14 void EVP_PKEY_CTX_free(EVP_PKEY_CTX *ctx); 15 16=head1 DESCRIPTION 17 18The EVP_PKEY_CTX_new() function allocates public key algorithm context using 19the algorithm specified in B<pkey> and ENGINE B<e>. 20 21The EVP_PKEY_CTX_new_id() function allocates public key algorithm context 22using the algorithm specified by B<id> and ENGINE B<e>. It is normally used 23when no B<EVP_PKEY> structure is associated with the operations, for example 24during parameter generation of key generation for some algorithms. 25 26EVP_PKEY_CTX_dup() duplicates the context B<ctx>. 27 28EVP_PKEY_CTX_free() frees up the context B<ctx>. 29If B<ctx> is NULL, nothing is done. 30 31=head1 NOTES 32 33The B<EVP_PKEY_CTX> structure is an opaque public key algorithm context used 34by the OpenSSL high level public key API. Contexts B<MUST NOT> be shared between 35threads: that is it is not permissible to use the same context simultaneously 36in two threads. 37 38=head1 RETURN VALUES 39 40EVP_PKEY_CTX_new(), EVP_PKEY_CTX_new_id(), EVP_PKEY_CTX_dup() returns either 41the newly allocated B<EVP_PKEY_CTX> structure of B<NULL> if an error occurred. 42 43EVP_PKEY_CTX_free() does not return a value. 44 45=head1 SEE ALSO 46 47L<EVP_PKEY_new(3)> 48 49=head1 HISTORY 50 51These functions were added in OpenSSL 1.0.0. 52 53=head1 COPYRIGHT 54 55Copyright 2006-2016 The OpenSSL Project Authors. All Rights Reserved. 56 57Licensed under the OpenSSL license (the "License"). You may not use 58this file except in compliance with the License. You can obtain a copy 59in the file LICENSE in the source distribution or at 60L<https://www.openssl.org/source/license.html>. 61 62=cut 63