| =pod |
| |
| =head1 NAME |
| |
| DSA_sign, DSA_sign_setup, DSA_verify - DSA signatures |
| |
| =head1 SYNOPSIS |
| |
| #include <openssl/dsa.h> |
| |
| The following functions have been deprecated since OpenSSL 3.0, and can be |
| hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value, |
| see L<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); |
| |
| =head1 DESCRIPTION |
| |
| All of the functions described on this page are deprecated. |
| Applications should instead use L<EVP_PKEY_sign_init(3)>, L<EVP_PKEY_sign(3)>, |
| L<EVP_PKEY_verify_init(3)> and L<EVP_PKEY_verify(3)>. |
| |
| DSA_sign() computes a digital signature on the B<len> byte message |
| digest B<dgst> using the private key B<dsa> and places its ASN.1 DER |
| encoding at B<sigret>. The length of the signature is places in |
| *B<siglen>. B<sigret> must point to DSA_size(B<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 B<sigbuf> of size B<siglen> |
| matches a given message digest B<dgst> of size B<len>. |
| B<dsa> is the signer's public key. |
| |
| The B<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 L<RAND(7)>), the operation will fail. |
| |
| =head1 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 |
| L<ERR_get_error(3)>. |
| |
| =head1 CONFORMING TO |
| |
| US Federal Information Processing Standard FIPS186-4 (Digital Signature |
| Standard, DSS), ANSI X9.30 |
| |
| =head1 SEE ALSO |
| |
| L<DSA_new(3)>, L<ERR_get_error(3)>, L<RAND_bytes(3)>, |
| L<DSA_do_sign(3)>, |
| L<RAND(7)> |
| |
| =head1 HISTORY |
| |
| All of these functions were deprecated in OpenSSL 3.0. |
| |
| =head1 COPYRIGHT |
| |
| Copyright 2000-2021 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 |
| L<https://www.openssl.org/source/license.html>. |
| |
| =cut |
