NAME
ENGINE_get_default_RSA,
ENGINE_get_default_DSA,
ENGINE_get_default_EC,
ENGINE_get_default_DH,
ENGINE_get_default_RAND,
ENGINE_get_cipher_engine,
ENGINE_get_digest_engine,
ENGINE_set_table_flags,
ENGINE_get_table_flags —
retrieve the default ENGINE for an
algorithm
SYNOPSIS
#include
<openssl/engine.h>
ENGINE *
ENGINE_get_default_RSA(void);
ENGINE *
ENGINE_get_default_DSA(void);
ENGINE *
ENGINE_get_default_EC(void);
ENGINE *
ENGINE_get_default_DH(void);
ENGINE *
ENGINE_get_default_RAND(void);
ENGINE *
ENGINE_get_cipher_engine(int
nid);
ENGINE *
ENGINE_get_digest_engine(int
nid);
void
ENGINE_set_table_flags(unsigned int
flags);
unsigned int
ENGINE_get_table_flags(void);
DESCRIPTION
These functions retrieve the current default ENGINE implementing the respective algorithm.
If a default engine was previously selected,
ENGINE_init(3) is called on it again and it is used.
Otherwise, these functions inspect the engines registered with the functions
documented in
ENGINE_register_RSA(3) in the order of the table for the
respective algorithm. If an inspected engine is already successfully
initialized,
ENGINE_init(3) is called on it again and it is used as the
new default. Otherwise, unless the global flag
ENGINE_TABLE_FLAG_NOINIT is set,
ENGINE_init(3) is tried on it. If it succeeds, that engine is
used as the new default. If it fails or if
ENGINE_TABLE_FLAG_NOINIT is set, inspection
continues with the next engine.
The global flag can be set by calling
ENGINE_set_table_flags()
with an argument of ENGINE_TABLE_FLAG_NOINIT or
cleared by calling it with an argument of 0. By default, the flag is not
set.
While all the other functions
operate on exactly one algorithm,
ENGINE_get_cipher_engine()
and
ENGINE_get_digest_engine()
are special in so far as they can handle multiple algorithms, identified by
the given nid. The default engine is remembered
separately for each algorithm.
Application programs rarely need to call these functions because they are called automatically when needed, in particular from RSA_new(3), DSA_new(3), EC_KEY_new(3), DH_new(3), EVP_CipherInit_ex(3), and EVP_DigestInit_ex(3).
RETURN VALUES
These functions return a functional reference to an
ENGINE object or NULL on
failure, in particular when no engine implementing the algorithm is
available, when
ENGINE_init(3) fails for all implementations, or when
insufficient memory is available. Even when these functions fail, the
application may still be able to use the algorithm in question because the
built-in implementation is used in that case, if one is available.
ENGINE_get_table_flags() returns
ENGINE_TABLE_FLAG_NOINIT if the global flag is set
or 0 otherwise.
SEE ALSO
ENGINE_init(3), ENGINE_new(3), ENGINE_register_RSA(3), ENGINE_set_default(3)
HISTORY
ENGINE_get_default_RSA(),
ENGINE_get_default_DSA(),
ENGINE_get_default_DH(), and
ENGINE_get_default_RAND() first appeared in OpenSSL
0.9.7 and have been available since OpenBSD 2.9.
ENGINE_get_cipher_engine(),
ENGINE_get_digest_engine(),
ENGINE_set_table_flags(), and
ENGINE_get_table_flags() first appeared in OpenSSL
0.9.7 and have been available since OpenBSD 3.2.
ENGINE_get_default_EC() first appeared in
OpenSSL 1.1.0 and has been available since OpenBSD
6.5.