OPENSSL_FORK_PREPARE(3) OpenSSL OPENSSL_FORK_PREPARE(3)
NAME
OPENSSL_fork_prepare, OPENSSL_fork_parent, OPENSSL_fork_child - OpenSSL
fork handlers
SYNOPSIS
#include <openssl/crypto.h>
void OPENSSL_fork_prepare(void);
void OPENSSL_fork_parent(void);
void OPENSSL_fork_child(void);
DESCRIPTION
OpenSSL has state that should be reset when a process forks. For
example, the entropy pool used to generate random numbers (and
therefore encryption keys) should not be shared across multiple
programs. The OPENSSL_fork_prepare(), OPENSSL_fork_parent(), and
OPENSSL_fork_child() functions are used to reset this internal state.
Platforms without fork(2) will probably not need to use these
functions. Platforms with fork(2) but without pthread_atfork(3) will
probably need to call them manually, as described in the following
paragraph. Platforms such as Linux that have both functions will
normally not need to call these functions as the OpenSSL library will
do so automatically.
OPENSSL_init_crypto(3) will register these functions with the
appropriate handler, when the OPENSSL_INIT_ATFORK flag is used. For
other applications, these functions can be called directly. They should
be used according to the calling sequence described by the
pthread_atfork(3) documentation, which is summarized here.
OPENSSL_fork_prepare() should be called before a fork() is done. After
the fork() returns, the parent process should call
OPENSSL_fork_parent() and the child process should call
OPENSSL_fork_child().
RETURN VALUES
OPENSSL_fork_prepare(), OPENSSL_fork_parent() and OPENSSL_fork_child()
do not return values.
SEE ALSO
OPENSSL_init_crypto(3)
HISTORY
These functions were added in OpenSSL 1.1.1.
COPYRIGHT
Copyright 2017-2019 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
<https://www.openssl.org/source/license.html>.
1.1.1k 2021-03-25 OPENSSL_FORK_PREPARE(3)