DSA_DO_SIGN
Section: OpenSSL (3)
Updated: 2021-03-26
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NAME
DSA_do_sign, DSA_do_verify - raw DSA signature operations
SYNOPSIS
#include <openssl/dsa.h>
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);
DESCRIPTION
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.
RETURN VALUES
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).
SEE ALSO
DSA_new(3),
ERR_get_error(3),
RAND_bytes(3),
DSA_SIG_new(3),
DSA_sign(3)
COPYRIGHT
Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
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
<https://www.openssl.org/source/license.html>.