| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="The message digest context."><meta name="keywords" content="rust, rustlang, rust-lang, md_ctx"><title>openssl::md_ctx - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../normalize.css"><link rel="stylesheet" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../ayu.css" disabled><link rel="stylesheet" href="../../dark.css" disabled><link rel="stylesheet" href="../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../storage.js"></script><script defer src="../../main.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../favicon.svg"></head><body class="rustdoc mod"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="mobile-topbar"><button class="sidebar-menu-toggle">☰</button><a class="sidebar-logo" href="../../openssl/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a><h2></h2></nav><nav class="sidebar"><a class="sidebar-logo" href="../../openssl/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a><h2 class="location"><a href="#">Module md_ctx</a></h2><div class="sidebar-elems"><section><ul class="block"><li><a href="#structs">Structs</a></li></ul></section></div></nav><main><div class="width-limiter"><nav class="sub"><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1 class="fqn">Module <a href="../index.html">openssl</a>::<wbr><a class="mod" href="#">md_ctx</a><button id="copy-path" onclick="copy_path(this)" title="Copy item path to clipboard"><img src="../../clipboard.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="srclink" href="../../src/openssl/md_ctx.rs.html#1-540">source</a> · <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class="inner">−</span>]</a></span></div><details class="rustdoc-toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>The message digest context.</p> |
| <h2 id="examples"><a href="#examples">Examples</a></h2> |
| <p>Compute the SHA256 checksum of data</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>openssl::md::Md; |
| <span class="kw">use </span>openssl::md_ctx::MdCtx; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>ctx = MdCtx::new().unwrap(); |
| ctx.digest_init(Md::sha256()).unwrap(); |
| ctx.digest_update(<span class="string">b"Some Crypto Text"</span>).unwrap(); |
| <span class="kw">let </span><span class="kw-2">mut </span>digest = [<span class="number">0</span>; <span class="number">32</span>]; |
| ctx.digest_final(<span class="kw-2">&mut </span>digest).unwrap(); |
| |
| <span class="macro">assert_eq!</span>( |
| digest, |
| <span class="kw-2">*</span><span class="string">b"\x60\x78\x56\x38\x8a\xca\x5c\x51\x83\xc4\xd1\x4d\xc8\xf9\xcc\xf2\ |
| \xa5\x21\xb3\x10\x93\x72\xfa\xd6\x7c\x55\xf5\xc9\xe3\xd1\x83\x19"</span>, |
| );</code></pre></div> |
| <p>Sign and verify data with RSA and SHA256</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>openssl::md::Md; |
| <span class="kw">use </span>openssl::md_ctx::MdCtx; |
| <span class="kw">use </span>openssl::pkey::PKey; |
| <span class="kw">use </span>openssl::rsa::Rsa; |
| |
| <span class="comment">// Generate a random RSA key. |
| </span><span class="kw">let </span>key = Rsa::generate(<span class="number">4096</span>).unwrap(); |
| <span class="kw">let </span>key = PKey::from_rsa(key).unwrap(); |
| |
| <span class="kw">let </span>text = <span class="string">b"Some Crypto Text"</span>; |
| |
| <span class="comment">// Create the signature. |
| </span><span class="kw">let </span><span class="kw-2">mut </span>ctx = MdCtx::new().unwrap(); |
| ctx.digest_sign_init(<span class="prelude-val">Some</span>(Md::sha256()), <span class="kw-2">&</span>key).unwrap(); |
| ctx.digest_sign_update(text).unwrap(); |
| <span class="kw">let </span><span class="kw-2">mut </span>signature = <span class="macro">vec!</span>[]; |
| ctx.digest_sign_final_to_vec(<span class="kw-2">&mut </span>signature).unwrap(); |
| |
| <span class="comment">// Verify the signature. |
| </span><span class="kw">let </span><span class="kw-2">mut </span>ctx = MdCtx::new().unwrap(); |
| ctx.digest_verify_init(<span class="prelude-val">Some</span>(Md::sha256()), <span class="kw-2">&</span>key).unwrap(); |
| ctx.digest_verify_update(text).unwrap(); |
| <span class="kw">let </span>valid = ctx.digest_verify_final(<span class="kw-2">&</span>signature).unwrap(); |
| <span class="macro">assert!</span>(valid);</code></pre></div> |
| <p><br /> |
| Compute and verify an HMAC-SHA256</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>openssl::md::Md; |
| <span class="kw">use </span>openssl::md_ctx::MdCtx; |
| <span class="kw">use </span>openssl::memcmp; |
| <span class="kw">use </span>openssl::pkey::PKey; |
| |
| <span class="comment">// Create a key with the HMAC secret. |
| </span><span class="kw">let </span>key = PKey::hmac(<span class="string">b"my secret"</span>).unwrap(); |
| |
| <span class="kw">let </span>text = <span class="string">b"Some Crypto Text"</span>; |
| |
| <span class="comment">// Compute the HMAC. |
| </span><span class="kw">let </span><span class="kw-2">mut </span>ctx = MdCtx::new().unwrap(); |
| ctx.digest_sign_init(<span class="prelude-val">Some</span>(Md::sha256()), <span class="kw-2">&</span>key).unwrap(); |
| ctx.digest_sign_update(text).unwrap(); |
| <span class="kw">let </span><span class="kw-2">mut </span>hmac = <span class="macro">vec!</span>[]; |
| ctx.digest_sign_final_to_vec(<span class="kw-2">&mut </span>hmac).unwrap(); |
| |
| <span class="comment">// Verify the HMAC. You can't use MdCtx to do this; instead use a constant time equality check. |
| </span><span class="kw">let </span>valid = memcmp::eq(<span class="kw-2">&</span>hmac, <span class="kw-2">&</span>target); |
| <span class="macro">assert!</span>(valid);</code></pre></div> |
| </div></details><h2 id="structs" class="small-section-header"><a href="#structs">Structs</a></h2><div class="item-table"><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.MdCtx.html" title="openssl::md_ctx::MdCtx struct">MdCtx</a></div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.MdCtxRef.html" title="openssl::md_ctx::MdCtxRef struct">MdCtxRef</a></div><div class="item-right docblock-short">A reference to an <a href="struct.MdCtx.html" title="MdCtx"><code>MdCtx</code></a>.</div></div></div></section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="openssl" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
