/usr/man/cat.3/OpenSSL_add_all_algorithms.3.Z

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>

        void OpenSSL_add_all_algorithms(void);
        void OpenSSL_add_all_ciphers(void);
        void OpenSSL_add_all_digests(void);

        void EVP_cleanup(void);

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().

       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.

       EVP_cleanup() removes all ciphers and digests from the table.

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 misbe-
       have 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(3), EVP_DigestInit(3), EVP_EncryptInit(3)

1.0.2t                            2019-09-10     OpenSSL_add_all_algorithms(3)
See also EVP_cleanup(3)
See also OpenSSL_add_all_ciphers(3)
See also OpenSSL_add_all_digests(3)