projects / thirdparty / openssl.git / blame
| Commit | Line | Data |
|---|---|---|
| 2915fe19 RS |
1 | =pod |
| 2 | ||
| 3 | =head1 NAME | |
| 4 | ||
| 5 | OPENSSL_fork_prepare, | |
| 6 | OPENSSL_fork_parent, | |
| 7 | OPENSSL_fork_child | |
| 8 | - OpenSSL fork handlers | |
| 9 | ||
| 10 | =head1 SYNOPSIS | |
| 11 | ||
| 12 | #include <openssl/crypto.h> | |
| 13 | ||
| 14 | void OPENSSL_fork_prepare(void); | |
| 15 | void OPENSSL_fork_parent(void); | |
| 16 | void OPENSSL_fork_child(void); | |
| 17 | ||
| 18 | =head1 DESCRIPTION | |
| 19 | ||
| 20 | OpenSSL has state that should be reset when a process forks. For example, | |
| 21 | the entropy pool used to generate random numbers (and therefore encryption | |
| 22 | keys) should not be shared across multiple programs. | |
| 23 | The OPENSSL_fork_prepare(), OPENSSL_fork_parent(), and OPENSSL_fork_child() | |
| 24 | functions are used to reset this internal state. | |
| 25 | ||
| 26 | Platforms without fork(2) will probably not need to use these functions. | |
| 933a73b9 | 27 | Platforms with fork(2) but without pthread_atfork(3) will probably need |
| 2915fe19 RS |
28 | to call them manually, as described in the following paragraph. Platforms |
| 29 | such as Linux that have both functions will normally not need to call these | |
| 30 | functions as the OpenSSL library will do so automatically. | |
| 31 | ||
| a970b14f | 32 | L<OPENSSL_init_crypto(3)> will register these functions with the appropriate |
| aa3b3285 | 33 | handler, when the B<OPENSSL_INIT_ATFORK> flag is used. For other |
| 2915fe19 | 34 | applications, these functions can be called directly. They should be used |
| 933a73b9 | 35 | according to the calling sequence described by the pthread_atfork(3) |
| 2915fe19 RS |
36 | documentation, which is summarized here. OPENSSL_fork_prepare() should |
| 37 | be called before a fork() is done. After the fork() returns, the parent | |
| 38 | process should call OPENSSL_fork_parent() and the child process should | |
| 39 | call OPENSSL_fork_child(). | |
| 40 | ||
| 1f13ad31 PY |
41 | =head1 RETURN VALUES |
| 42 | ||
| 43 | OPENSSL_fork_prepare(), OPENSSL_fork_parent() and OPENSSL_fork_child() do not | |
| 44 | return values. | |
| 45 | ||
| 2915fe19 RS |
46 | =head1 SEE ALSO |
| 47 | ||
| 48 | L<OPENSSL_init_crypto(3)> | |
| 49 | ||
| 50 | =head1 HISTORY | |
| 51 | ||
| 52 | These functions were added in OpenSSL 1.1.1. | |
| 53 | ||
| 54 | =head1 COPYRIGHT | |
| 55 | ||
| 61f805c1 | 56 | Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved. |
| 2915fe19 | 57 | |
| 4746f25a | 58 | Licensed under the Apache License 2.0 (the "License"). You may not use |
| 2915fe19 RS |
59 | this file except in compliance with the License. You can obtain a copy |
| 60 | in the file LICENSE in the source distribution or at | |
| 61 | L<https://www.openssl.org/source/license.html>. | |
| 62 | ||
| 63 | =cut |