DSA_SIGN

Section: OpenSSL (3SSL)
Updated: 2024-03-03
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NAME

DSA_sign, DSA_sign_setup, DSA_verify - DSA signatures  

SYNOPSIS

 #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):

 int DSA_sign(int type, const unsigned char *dgst, int len,
              unsigned char *sigret, unsigned int *siglen, DSA *dsa);

 int DSA_sign_setup(DSA *dsa, BN_CTX *ctx, BIGNUM **kinvp, BIGNUM **rp);

 int DSA_verify(int type, const unsigned char *dgst, int len,
                unsigned char *sigbuf, int siglen, DSA *dsa);

 

DESCRIPTION

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_sign() computes a digital signature on the len byte message digest dgst using the private key dsa and places its ASN.1 DER encoding at sigret. The length of the signature is places in *siglen. sigret must point to DSA_size(dsa) bytes of memory.

DSA_sign_setup() is defined only for backward binary compatibility and should not be used. Since OpenSSL 1.1.0 the DSA type is opaque and the output of DSA_sign_setup() cannot be used anyway: calling this function will only cause overhead, and does not affect the actual signature (pre-)computation.

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

The type parameter is ignored.

The random generator must be seeded when DSA_sign() (or DSA_sign_setup()) is called. If the automatic seeding or reseeding of the OpenSSL CSPRNG fails due to external circumstances (see RAND(7)), the operation will fail.  

RETURN VALUES

DSA_sign() and DSA_sign_setup() return 1 on success, 0 on error. DSA_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).  

CONFORMING TO

US Federal Information Processing Standard FIPS186-4 (Digital Signature Standard, DSS), ANSI X9.30  

SEE ALSO

DSA_new(3), ERR_get_error(3), RAND_bytes(3), DSA_do_sign(3), RAND(7)  

HISTORY

All of these functions were deprecated in OpenSSL 3.0.  

COPYRIGHT

Copyright 2000-2022 The OpenSSL Project Authors. All Rights Reserved.

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>.


 

Index

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUES
CONFORMING TO
SEE ALSO
HISTORY
COPYRIGHT

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Time: 13:35:44 GMT, March 28, 2024