=head1 SYNOPSIS
#include <openssl/dsa.h>
- #include <openssl/engine.h>
void DSA_set_default_method(const DSA_METHOD *meth);
DSA_get_default_method() returns a pointer to the current default
DSA_METHOD. However, the meaningfulness of this result is dependent on
-whether the ENGINE API is being used, so this function is no longer
+whether the ENGINE API is being used, so this function is no longer
recommended.
DSA_set_method() selects B<meth> to perform all operations using the key
work with certain DSA_METHOD implementations (eg. from an ENGINE module
that supports embedded hardware-protected keys), and in such cases
attempting to change the DSA_METHOD for the key can have unexpected
-results.
+results. See L<DSA_meth_new> for information on constructing custom DSA_METHOD
+objects;
DSA_new_method() allocates and initializes a DSA structure so that B<engine>
will be used for the DSA operations. If B<engine> is NULL, the default engine
for DSA operations is used, and if no default ENGINE is set, the DSA_METHOD
controlled by DSA_set_default_method() is used.
-=head1 THE DSA_METHOD STRUCTURE
-
-struct
- {
- /* name of the implementation */
- const char *name;
-
- /* sign */
- DSA_SIG *(*dsa_do_sign)(const unsigned char *dgst, int dlen,
- DSA *dsa);
-
- /* pre-compute k^-1 and r */
- int (*dsa_sign_setup)(DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp,
- BIGNUM **rp);
-
- /* verify */
- int (*dsa_do_verify)(const unsigned char *dgst, int dgst_len,
- DSA_SIG *sig, DSA *dsa);
-
- /* compute rr = a1^p1 * a2^p2 mod m (May be NULL for some
- implementations) */
- int (*dsa_mod_exp)(DSA *dsa, BIGNUM *rr, BIGNUM *a1, BIGNUM *p1,
- BIGNUM *a2, BIGNUM *p2, BIGNUM *m,
- BN_CTX *ctx, BN_MONT_CTX *in_mont);
-
- /* compute r = a ^ p mod m (May be NULL for some implementations) */
- int (*bn_mod_exp)(DSA *dsa, BIGNUM *r, BIGNUM *a,
- const BIGNUM *p, const BIGNUM *m,
- BN_CTX *ctx, BN_MONT_CTX *m_ctx);
-
- /* called at DSA_new */
- int (*init)(DSA *DSA);
-
- /* called at DSA_free */
- int (*finish)(DSA *DSA);
-
- int flags;
-
- char *app_data; /* ?? */
-
- } DSA_METHOD;
-
=head1 RETURN VALUES
DSA_OpenSSL() and DSA_get_default_method() return pointers to the respective
method was supplied by an ENGINE).
DSA_new_method() returns NULL and sets an error code that can be
-obtained by L<ERR_get_error(3)|ERR_get_error(3)> if the allocation
+obtained by L<ERR_get_error(3)> if the allocation
fails. Otherwise it returns a pointer to the newly allocated structure.
-=head1 NOTES
-
-As of version 0.9.7, DSA_METHOD implementations are grouped together with other
-algorithmic APIs (eg. RSA_METHOD, EVP_CIPHER, etc) in B<ENGINE> modules. If a
-default ENGINE is specified for DSA functionality using an ENGINE API function,
-that will override any DSA defaults set using the DSA API (ie.
-DSA_set_default_method()). For this reason, the ENGINE API is the recommended way
-to control default implementations for use in DSA and other cryptographic
-algorithms.
-
=head1 SEE ALSO
-L<dsa(3)|dsa(3)>, L<DSA_new(3)|DSA_new(3)>
+L<dsa(3)>, L<DSA_new(3)>, L<DSA_meth_new(3)>
-=head1 HISTORY
+=head1 COPYRIGHT
-DSA_set_default_method(), DSA_get_default_method(), DSA_set_method(),
-DSA_new_method() and DSA_OpenSSL() were added in OpenSSL 0.9.4.
+Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
-DSA_set_default_openssl_method() and DSA_get_default_openssl_method() replaced
-DSA_set_default_method() and DSA_get_default_method() respectively, and
-DSA_set_method() and DSA_new_method() were altered to use B<ENGINE>s rather than
-B<DSA_METHOD>s during development of the engine version of OpenSSL 0.9.6. For
-0.9.7, the handling of defaults in the ENGINE API was restructured so that this
-change was reversed, and behaviour of the other functions resembled more closely
-the previous behaviour. The behaviour of defaults in the ENGINE API now
-transparently overrides the behaviour of defaults in the DSA API without
-requiring changing these function prototypes.
+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
+L<https://www.openssl.org/source/license.html>.
=cut