147 lines
4.7 KiB
HTML
Executable File
147 lines
4.7 KiB
HTML
Executable File
<?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>EVP_PKEY_decrypt</title>
|
|
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
|
|
<link rev="made" href="mailto:root@localhost" />
|
|
</head>
|
|
|
|
<body style="background-color: white">
|
|
|
|
|
|
<!-- INDEX BEGIN -->
|
|
<div name="index">
|
|
<p><a name="__index__"></a></p>
|
|
|
|
<ul>
|
|
|
|
<li><a href="#name">NAME</a></li>
|
|
<li><a href="#synopsis">SYNOPSIS</a></li>
|
|
<li><a href="#description">DESCRIPTION</a></li>
|
|
<li><a href="#notes">NOTES</a></li>
|
|
<li><a href="#return_values">RETURN VALUES</a></li>
|
|
<li><a href="#examples">EXAMPLES</a></li>
|
|
<li><a href="#see_also">SEE ALSO</a></li>
|
|
<li><a href="#history">HISTORY</a></li>
|
|
<li><a href="#copyright">COPYRIGHT</a></li>
|
|
</ul>
|
|
|
|
<hr name="index" />
|
|
</div>
|
|
<!-- INDEX END -->
|
|
|
|
<p>
|
|
</p>
|
|
<hr />
|
|
<h1><a name="name">NAME</a></h1>
|
|
<p>EVP_PKEY_decrypt_init, EVP_PKEY_decrypt - decrypt using a public key algorithm</p>
|
|
<p>
|
|
</p>
|
|
<hr />
|
|
<h1><a name="synopsis">SYNOPSIS</a></h1>
|
|
<pre>
|
|
#include <openssl/evp.h></pre>
|
|
<pre>
|
|
int EVP_PKEY_decrypt_init(EVP_PKEY_CTX *ctx);
|
|
int EVP_PKEY_decrypt(EVP_PKEY_CTX *ctx,
|
|
unsigned char *out, size_t *outlen,
|
|
const unsigned char *in, size_t inlen);</pre>
|
|
<p>
|
|
</p>
|
|
<hr />
|
|
<h1><a name="description">DESCRIPTION</a></h1>
|
|
<p>The <code>EVP_PKEY_decrypt_init()</code> function initializes a public key algorithm
|
|
context using key <strong>pkey</strong> for a decryption operation.</p>
|
|
<p>The <code>EVP_PKEY_decrypt()</code> function performs a public key decryption operation
|
|
using <strong>ctx</strong>. The data to be decrypted is specified using the <strong>in</strong> and
|
|
<strong>inlen</strong> parameters. If <strong>out</strong> is <strong>NULL</strong> then the maximum size of the output
|
|
buffer is written to the <strong>outlen</strong> parameter. If <strong>out</strong> is not <strong>NULL</strong> then
|
|
before the call the <strong>outlen</strong> parameter should contain the length of the
|
|
<strong>out</strong> buffer, if the call is successful the decrypted data is written to
|
|
<strong>out</strong> and the amount of data written to <strong>outlen</strong>.</p>
|
|
<p>
|
|
</p>
|
|
<hr />
|
|
<h1><a name="notes">NOTES</a></h1>
|
|
<p>After the call to <code>EVP_PKEY_decrypt_init()</code> algorithm specific control
|
|
operations can be performed to set any appropriate parameters for the
|
|
operation.</p>
|
|
<p>The function <code>EVP_PKEY_decrypt()</code> can be called more than once on the same
|
|
context if several operations are performed using the same parameters.</p>
|
|
<p>
|
|
</p>
|
|
<hr />
|
|
<h1><a name="return_values">RETURN VALUES</a></h1>
|
|
<p><code>EVP_PKEY_decrypt_init()</code> and <code>EVP_PKEY_decrypt()</code> return 1 for success and 0
|
|
or a negative value for failure. In particular a return value of -2
|
|
indicates the operation is not supported by the public key algorithm.</p>
|
|
<p>
|
|
</p>
|
|
<hr />
|
|
<h1><a name="examples">EXAMPLES</a></h1>
|
|
<p>Decrypt data using OAEP (for RSA keys):</p>
|
|
<pre>
|
|
#include <openssl/evp.h>
|
|
#include <openssl/rsa.h></pre>
|
|
<pre>
|
|
EVP_PKEY_CTX *ctx;
|
|
ENGINE *eng;
|
|
unsigned char *out, *in;
|
|
size_t outlen, inlen;
|
|
EVP_PKEY *key;</pre>
|
|
<pre>
|
|
/*
|
|
* NB: assumes key, eng, in, inlen are already set up
|
|
* and that key is an RSA private key
|
|
*/
|
|
ctx = EVP_PKEY_CTX_new(key, eng);
|
|
if (!ctx)
|
|
/* Error occurred */
|
|
if (EVP_PKEY_decrypt_init(ctx) <= 0)
|
|
/* Error */
|
|
if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_OAEP_PADDING) <= 0)
|
|
/* Error */</pre>
|
|
<pre>
|
|
/* Determine buffer length */
|
|
if (EVP_PKEY_decrypt(ctx, NULL, &outlen, in, inlen) <= 0)
|
|
/* Error */</pre>
|
|
<pre>
|
|
out = OPENSSL_malloc(outlen);</pre>
|
|
<pre>
|
|
if (!out)
|
|
/* malloc failure */</pre>
|
|
<pre>
|
|
if (EVP_PKEY_decrypt(ctx, out, &outlen, in, inlen) <= 0)
|
|
/* Error */</pre>
|
|
<pre>
|
|
/* Decrypted data is outlen bytes written to buffer out */</pre>
|
|
<p>
|
|
</p>
|
|
<hr />
|
|
<h1><a name="see_also">SEE ALSO</a></h1>
|
|
<p><em>EVP_PKEY_CTX_new(3)</em>,
|
|
<em>EVP_PKEY_encrypt(3)</em>,
|
|
<em>EVP_PKEY_sign(3)</em>,
|
|
<em>EVP_PKEY_verify(3)</em>,
|
|
<em>EVP_PKEY_verify_recover(3)</em>,
|
|
<em>EVP_PKEY_derive(3)</em></p>
|
|
<p>
|
|
</p>
|
|
<hr />
|
|
<h1><a name="history">HISTORY</a></h1>
|
|
<p>These functions were added in OpenSSL 1.0.0.</p>
|
|
<p>
|
|
</p>
|
|
<hr />
|
|
<h1><a name="copyright">COPYRIGHT</a></h1>
|
|
<p>Copyright 2006-2018 The OpenSSL Project Authors. All Rights Reserved.</p>
|
|
<p>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
|
|
<a href="https://www.openssl.org/source/license.html">https://www.openssl.org/source/license.html</a>.</p>
|
|
|
|
</body>
|
|
|
|
</html>
|