NAME
EVP_add_cipher,
EVP_add_cipher_alias,
EVP_delete_cipher_alias,
EVP_add_digest,
EVP_add_digest_alias,
EVP_delete_digest_alias —
maintain lookup tables for cipher and
digest names
SYNOPSIS
#include
<openssl/evp.h>
int
EVP_add_cipher(const EVP_CIPHER
*cipher);
int
EVP_add_cipher_alias(const char
*name, const char *alias);
int
EVP_delete_cipher_alias(const char
*alias);
int
EVP_add_digest(const EVP_MD
*md);
int
EVP_add_digest_alias(const char
*name, const char *alias);
int
EVP_delete_digest_alias(const char
*alias);
DESCRIPTION
EVP_add_cipher()
adds cipher to a global lookup table so that it can be
retrieved with
EVP_get_cipherbyname(3) using both its long and short names,
as determined by the cipher's NID via
OBJ_nid2ln(3) and
OBJ_nid2sn(3). It is the caller's responsibility to ensure
that the long and short names are not NULL.
Internally, the lookup table is the global associative array and
OBJ_NAME_add(3) is used to add two key-value pairs with value
pointer cipher and the keys consisting of the names
and the type OBJ_NAME_TYPE_CIPHER_METH.
EVP_add_cipher_alias()
and
EVP_delete_cipher_alias()
add and remove the alias for the cipher
name. They are implemented as macros wrapping
OBJ_NAME_add(3) and
OBJ_NAME_remove(3) with type set to the
bitwise or of OBJ_NAME_TYPE_CIPHER_METH and
OBJ_NAME_ALIAS.
EVP_add_digest()
adds md to a global lookup table so that it can be
retrieved with
EVP_get_digestbyname(3) using both its long and short names,
as determined by the md's NID via
OBJ_nid2ln(3) and
OBJ_nid2sn(3). If the md has an
associated public key signing algorithm (see
EVP_MD_pkey_type(3)) distinct from the
md, the signing algorithm's short and long names are
added as aliases for the short name of md. It is the
caller's responsibility to ensure that all long and short names are not
NULL. Internally, the lookup table is the global
associative array and
OBJ_NAME_add(3) is used to add two key-value pairs with value
pointer md and the keys consisting of the names and
the type OBJ_NAME_TYPE_MD_METH. The aliases are
added with EVP_add_digest_alias().
EVP_add_digest_alias()
and
EVP_delete_digest_alias()
add and remove the alias for the digest
name. They are implemented as macros wrapping
OBJ_NAME_add(3) and
OBJ_NAME_remove(3) with type set to the
bitwise or of OBJ_NAME_TYPE_MD_METH and
OBJ_NAME_ALIAS.
RETURN VALUES
EVP_add_cipher(),
EVP_add_cipher_alias(),
EVP_add_digest(), and
EVP_add_digest_alias() return 1 on success or 0 if
memory allocation fails.
EVP_delete_cipher_alias() and
EVP_delete_digest_alias() return 1 if one alias was
removed or 0 otherwise.
SEE ALSO
evp(3), EVP_CIPHER_meth_new(3), EVP_get_cipherbyname(3), EVP_get_digestbyname(3), EVP_MD_meth_new(3), OBJ_create(3), OBJ_NAME_add(3), OpenSSL_add_all_algorithms(3)
HISTORY
EVP_add_cipher() and
EVP_add_digest() first appeared in OpenSSL 0.9.0 and
have been available since OpenBSD 2.4.
EVP_add_cipher_alias(),
EVP_delete_cipher_alias(),
EVP_add_digest_alias(), and
EVP_delete_digest_alias() first appeared in OpenSSL
0.9.4 and have been available since OpenBSD 2.6.
BUGS
Key-value pairs already added before an error occurred remain in the global associative array, leaving it in an unknown state.
While aliases can be added and removed, there is no dedicated API to remove added ciphers or digests.