| <!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="Writes a version negotiation packet."><title>negotiate_version in quiche - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-46f98efaafac5295.ttf.woff2,FiraSans-Regular-018c141bf0843ffd.woff2,FiraSans-Medium-8f9a781e4970d388.woff2,SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2,SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2" crossorigin href="../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../static.files/rustdoc-b21aa549bf6d91ff.css"><meta name="rustdoc-vars" data-root-path="../" data-static-root-path="../static.files/" data-current-crate="quiche" data-themes="" data-resource-suffix="" data-rustdoc-version="1.80.0-nightly (79734f1db 2024-05-02)" data-channel="nightly" data-search-js="search-bf21c90c8c1d92b1.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../static.files/storage-e32f0c247825364d.js"></script><script defer src="sidebar-items.js"></script><script defer src="../static.files/main-20a3ad099b048cf2.js"></script><noscript><link rel="stylesheet" href="../static.files/noscript-09095024cf37855e.css"></noscript><link rel="alternate icon" type="image/png" href="../static.files/favicon-32x32-422f7d1d52889060.png"><link rel="icon" type="image/svg+xml" href="../static.files/favicon-2c020d218678b618.svg"></head><body class="rustdoc fn"><!--[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" title="show sidebar"></button></nav><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../quiche/index.html">quiche</a><span class="version">0.21.0</span></h2></div><div class="sidebar-elems"></div></nav><div class="sidebar-resizer"></div><main><div class="width-limiter"><nav class="sub"><form class="search-form"><span></span><div id="sidebar-button" tabindex="-1"><a href="../quiche/all.html" title="show sidebar"></a></div><input class="search-input" name="search" aria-label="Run search in the documentation" autocomplete="off" spellcheck="false" placeholder="Type ‘S’ or ‘/’ to search, ‘?’ for more options…" type="search"><div id="help-button" tabindex="-1"><a href="../help.html" title="help">?</a></div><div id="settings-menu" tabindex="-1"><a href="../settings.html" title="settings">Settings</a></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1>Function <a href="index.html">quiche</a>::<wbr><a class="fn" href="#">negotiate_version</a><button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><span class="out-of-band"><a class="src" href="../src/quiche/lib.rs.html#1642-1646">source</a> · <button id="toggle-all-docs" title="collapse all docs">[<span>−</span>]</button></span></div><pre class="rust item-decl"><code>pub fn negotiate_version( |
| scid: &<a class="struct" href="struct.ConnectionId.html" title="struct quiche::ConnectionId">ConnectionId</a><'_>, |
| dcid: &<a class="struct" href="struct.ConnectionId.html" title="struct quiche::ConnectionId">ConnectionId</a><'_>, |
| out: &mut [<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u8.html">u8</a>] |
| ) -> <a class="type" href="type.Result.html" title="type quiche::Result">Result</a><<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.usize.html">usize</a>></code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Writes a version negotiation packet.</p> |
| <p>The <code>scid</code> and <code>dcid</code> parameters are the source connection ID and the |
| destination connection ID extracted from the received client’s Initial |
| packet that advertises an unsupported version.</p> |
| <h3 id="examples"><a class="doc-anchor" href="#examples">§</a>Examples:</h3> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>(len, src) = socket.recv_from(<span class="kw-2">&mut </span>buf).unwrap(); |
| |
| <span class="kw">let </span>hdr = |
| quiche::Header::from_slice(<span class="kw-2">&mut </span>buf[..len], quiche::MAX_CONN_ID_LEN)<span class="question-mark">?</span>; |
| |
| <span class="kw">if </span>hdr.version != quiche::PROTOCOL_VERSION { |
| <span class="kw">let </span>len = quiche::negotiate_version(<span class="kw-2">&</span>hdr.scid, <span class="kw-2">&</span>hdr.dcid, <span class="kw-2">&mut </span>out)<span class="question-mark">?</span>; |
| socket.send_to(<span class="kw-2">&</span>out[..len], <span class="kw-2">&</span>src).unwrap(); |
| }</code></pre></div> |
| </div></details></section></div></main></body></html> |
