Edit File: DSA_verify.html
<?xml version="1.0" ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>DSA_sign</title> <meta http-equiv="content-type" content="text/html; charset=utf-8" /> <link rev="made" href="mailto:root@localhost" /> </head> <body> <ul id="index"> <li><a href="#NAME">NAME</a></li> <li><a href="#SYNOPSIS">SYNOPSIS</a></li> <li><a href="#DESCRIPTION">DESCRIPTION</a></li> <li><a href="#RETURN-VALUES">RETURN VALUES</a></li> <li><a href="#CONFORMING-TO">CONFORMING TO</a></li> <li><a href="#SEE-ALSO">SEE ALSO</a></li> <li><a href="#COPYRIGHT">COPYRIGHT</a></li> </ul> <h1 id="NAME">NAME</h1> <p>DSA_sign, DSA_sign_setup, DSA_verify - DSA signatures</p> <h1 id="SYNOPSIS">SYNOPSIS</h1> <pre><code> #include <openssl/dsa.h> 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);</code></pre> <h1 id="DESCRIPTION">DESCRIPTION</h1> <p>DSA_sign() computes a digital signature on the <b>len</b> byte message digest <b>dgst</b> using the private key <b>dsa</b> and places its ASN.1 DER encoding at <b>sigret</b>. The length of the signature is places in *<b>siglen</b>. <b>sigret</b> must point to DSA_size(<b>dsa</b>) bytes of memory.</p> <p>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.</p> <p>DSA_verify() verifies that the signature <b>sigbuf</b> of size <b>siglen</b> matches a given message digest <b>dgst</b> of size <b>len</b>. <b>dsa</b> is the signer's public key.</p> <p>The <b>type</b> parameter is ignored.</p> <p>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 <a href="../man7/RAND.html">RAND(7)</a>), the operation will fail.</p> <h1 id="RETURN-VALUES">RETURN VALUES</h1> <p>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 <a href="../man3/ERR_get_error.html">ERR_get_error(3)</a>.</p> <h1 id="CONFORMING-TO">CONFORMING TO</h1> <p>US Federal Information Processing Standard FIPS 186 (Digital Signature Standard, DSS), ANSI X9.30</p> <h1 id="SEE-ALSO">SEE ALSO</h1> <p><a href="../man3/DSA_new.html">DSA_new(3)</a>, <a href="../man3/ERR_get_error.html">ERR_get_error(3)</a>, <a href="../man3/RAND_bytes.html">RAND_bytes(3)</a>, <a href="../man3/DSA_do_sign.html">DSA_do_sign(3)</a>, <a href="../man7/RAND.html">RAND(7)</a></p> <h1 id="COPYRIGHT">COPYRIGHT</h1> <p>Copyright 2000-2019 The OpenSSL Project Authors. All Rights Reserved.</p> <p>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 <a href="https://www.openssl.org/source/license.html">https://www.openssl.org/source/license.html</a>.</p> </body> </html>