OpenSSL

Cryptography and SSL/TLS Toolkit

OpenSSL_add_all_algorithms

NAME

OpenSSL_add_all_algorithms, OpenSSL_add_all_ciphers, OpenSSL_add_all_digests, EVP_cleanup - add algorithms to internal table

SYNOPSIS

 #include <openssl/evp.h>

Deprecated:

 # if OPENSSL_API_COMPAT < 0x10100000L
 void OpenSSL_add_all_algorithms(void);
 void OpenSSL_add_all_ciphers(void);
 void OpenSSL_add_all_digests(void);

 void EVP_cleanup(void)
# endif

DESCRIPTION

OpenSSL keeps an internal table of digest algorithms and ciphers. It uses this table to lookup ciphers via functions such as EVP_get_cipher_byname(). In OpenSSL versions prior to 1.1.0 these functions initialised and de-initialised this table. From OpenSSL 1.1.0 they are deprecated. No explicit initialisation or de-initialisation is required. See OPENSSL_init_crypto for further information.

OpenSSL_add_all_digests() adds all digest algorithms to the table.

OpenSSL_add_all_algorithms() adds all algorithms to the table (digests and ciphers).

OpenSSL_add_all_ciphers() adds all encryption algorithms to the table including password based encryption algorithms.

In versions prior to 1.1.0 EVP_cleanup() removed all ciphers and digests from the table. It no longer has any effect in OpenSSL 1.1.0.

RETURN VALUES

None of the functions return a value.

NOTES

A typical application will call OpenSSL_add_all_algorithms() initially and EVP_cleanup() before exiting.

An application does not need to add algorithms to use them explicitly, for example by EVP_sha1(). It just needs to add them if it (or any of the functions it calls) needs to lookup algorithms.

The cipher and digest lookup functions are used in many parts of the library. If the table is not initialized several functions will misbehave and complain they cannot find algorithms. This includes the PEM, PKCS#12, SSL and S/MIME libraries. This is a common query in the OpenSSL mailing lists.

Calling OpenSSL_add_all_algorithms() links in all algorithms: as a result a statically linked executable can be quite large. If this is important it is possible to just add the required ciphers and digests.

BUGS

Although the functions do not return error codes it is possible for them to fail. This will only happen as a result of a memory allocation failure so this is not too much of a problem in practice.

SEE ALSO

evp, EVP_DigestInit, EVP_EncryptInit

HISTORY

The OpenSSL_add_all_algorithms(), OpenSSL_add_all_ciphers(), OpenSSL_add_all_digests(), and EVP_cleanup(), functions were deprecated in OpenSSL 1.1.0 by OPENSSL_init_crypto().

Copyright 2000-2016 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.