DSA_do_sign, DSA_do_verify - raw DSA signature operations

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       Licensed under the Apache License 2.0 (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>.

3.5.0                                              2025-06-04                                  DSA_DO_SIGN(3SSL)

       All of the functions described on this page are deprecated.  Applications should instead use
       EVP_PKEY_sign_init(3), EVP_PKEY_sign(3), EVP_PKEY_verify_init(3) and EVP_PKEY_verify(3).

       DSA_do_sign() computes a digital signature on the len byte message digest dgst using the private key dsa
       and returns it in a newly allocated DSA_SIG structure.

       DSA_sign_setup(3) may be used to precompute part of the signing operation in case signature generation is
       time-critical.

       DSA_do_verify() verifies that the signature sig matches a given message digest dgst of size len.  dsa is
       the signer's public key.

       All of these functions were deprecated in OpenSSL 3.0.

       DSA_do_sign, DSA_do_verify - raw DSA signature operations

DSA_do_sign() returns the signature, NULL on error.  DSA_do_verify() returns 1 for a valid signature, 0
       for an incorrect signature and -1 on error. The error codes can be obtained by ERR_get_error(3).

DSA_new(3), ERR_get_error(3), RAND_bytes(3), DSA_SIG_new(3), DSA_sign(3)

        #include <openssl/dsa.h>

       The following functions have been deprecated since OpenSSL 3.0, and can be hidden entirely by defining
       OPENSSL_API_COMPAT with a suitable version value, see openssl_user_macros(7):

        DSA_SIG *DSA_do_sign(const unsigned char *dgst, int dlen, DSA *dsa);

        int DSA_do_verify(const unsigned char *dgst, int dgst_len,
                          DSA_SIG *sig, DSA *dsa);