| <!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="Source of the Rust file `/root/.cargo/git/checkouts/incubator-teaclave-crates-c8106113f74feefc/ede1f68/rustls-0.19.1/rustls/src/record_layer.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>record_layer.rs - source</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="../../source-script.js"></script><script defer src="../../source-files.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 source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../rustls/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../rustls/index.html"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></a><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="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
| <span id="2">2</span> |
| <span id="3">3</span> |
| <span id="4">4</span> |
| <span id="5">5</span> |
| <span id="6">6</span> |
| <span id="7">7</span> |
| <span id="8">8</span> |
| <span id="9">9</span> |
| <span id="10">10</span> |
| <span id="11">11</span> |
| <span id="12">12</span> |
| <span id="13">13</span> |
| <span id="14">14</span> |
| <span id="15">15</span> |
| <span id="16">16</span> |
| <span id="17">17</span> |
| <span id="18">18</span> |
| <span id="19">19</span> |
| <span id="20">20</span> |
| <span id="21">21</span> |
| <span id="22">22</span> |
| <span id="23">23</span> |
| <span id="24">24</span> |
| <span id="25">25</span> |
| <span id="26">26</span> |
| <span id="27">27</span> |
| <span id="28">28</span> |
| <span id="29">29</span> |
| <span id="30">30</span> |
| <span id="31">31</span> |
| <span id="32">32</span> |
| <span id="33">33</span> |
| <span id="34">34</span> |
| <span id="35">35</span> |
| <span id="36">36</span> |
| <span id="37">37</span> |
| <span id="38">38</span> |
| <span id="39">39</span> |
| <span id="40">40</span> |
| <span id="41">41</span> |
| <span id="42">42</span> |
| <span id="43">43</span> |
| <span id="44">44</span> |
| <span id="45">45</span> |
| <span id="46">46</span> |
| <span id="47">47</span> |
| <span id="48">48</span> |
| <span id="49">49</span> |
| <span id="50">50</span> |
| <span id="51">51</span> |
| <span id="52">52</span> |
| <span id="53">53</span> |
| <span id="54">54</span> |
| <span id="55">55</span> |
| <span id="56">56</span> |
| <span id="57">57</span> |
| <span id="58">58</span> |
| <span id="59">59</span> |
| <span id="60">60</span> |
| <span id="61">61</span> |
| <span id="62">62</span> |
| <span id="63">63</span> |
| <span id="64">64</span> |
| <span id="65">65</span> |
| <span id="66">66</span> |
| <span id="67">67</span> |
| <span id="68">68</span> |
| <span id="69">69</span> |
| <span id="70">70</span> |
| <span id="71">71</span> |
| <span id="72">72</span> |
| <span id="73">73</span> |
| <span id="74">74</span> |
| <span id="75">75</span> |
| <span id="76">76</span> |
| <span id="77">77</span> |
| <span id="78">78</span> |
| <span id="79">79</span> |
| <span id="80">80</span> |
| <span id="81">81</span> |
| <span id="82">82</span> |
| <span id="83">83</span> |
| <span id="84">84</span> |
| <span id="85">85</span> |
| <span id="86">86</span> |
| <span id="87">87</span> |
| <span id="88">88</span> |
| <span id="89">89</span> |
| <span id="90">90</span> |
| <span id="91">91</span> |
| <span id="92">92</span> |
| <span id="93">93</span> |
| <span id="94">94</span> |
| <span id="95">95</span> |
| <span id="96">96</span> |
| <span id="97">97</span> |
| <span id="98">98</span> |
| <span id="99">99</span> |
| <span id="100">100</span> |
| <span id="101">101</span> |
| <span id="102">102</span> |
| <span id="103">103</span> |
| <span id="104">104</span> |
| <span id="105">105</span> |
| <span id="106">106</span> |
| <span id="107">107</span> |
| <span id="108">108</span> |
| <span id="109">109</span> |
| <span id="110">110</span> |
| <span id="111">111</span> |
| <span id="112">112</span> |
| <span id="113">113</span> |
| <span id="114">114</span> |
| <span id="115">115</span> |
| <span id="116">116</span> |
| <span id="117">117</span> |
| <span id="118">118</span> |
| <span id="119">119</span> |
| <span id="120">120</span> |
| <span id="121">121</span> |
| <span id="122">122</span> |
| <span id="123">123</span> |
| <span id="124">124</span> |
| <span id="125">125</span> |
| <span id="126">126</span> |
| <span id="127">127</span> |
| <span id="128">128</span> |
| <span id="129">129</span> |
| <span id="130">130</span> |
| <span id="131">131</span> |
| <span id="132">132</span> |
| <span id="133">133</span> |
| <span id="134">134</span> |
| <span id="135">135</span> |
| <span id="136">136</span> |
| <span id="137">137</span> |
| <span id="138">138</span> |
| <span id="139">139</span> |
| <span id="140">140</span> |
| <span id="141">141</span> |
| <span id="142">142</span> |
| <span id="143">143</span> |
| </pre><pre class="rust"><code><span class="kw">use </span><span class="kw">crate</span>::cipher::{MessageDecrypter, MessageEncrypter}; |
| <span class="kw">use </span><span class="kw">crate</span>::error::TLSError; |
| <span class="kw">use </span><span class="kw">crate</span>::msgs::message::{BorrowMessage, Message}; |
| |
| <span class="kw">static </span>SEQ_SOFT_LIMIT: u64 = <span class="number">0xffff_ffff_ffff_0000u64</span>; |
| <span class="kw">static </span>SEQ_HARD_LIMIT: u64 = <span class="number">0xffff_ffff_ffff_fffeu64</span>; |
| |
| <span class="attribute">#[derive(PartialEq)] |
| </span><span class="kw">enum </span>DirectionState { |
| <span class="doccomment">/// No keying material. |
| </span>Invalid, |
| |
| <span class="doccomment">/// Keying material present, but not yet in use. |
| </span>Prepared, |
| |
| <span class="doccomment">/// Keying material in use. |
| </span>Active, |
| } |
| |
| <span class="kw">pub struct </span>RecordLayer { |
| message_encrypter: Box<<span class="kw">dyn </span>MessageEncrypter>, |
| message_decrypter: Box<<span class="kw">dyn </span>MessageDecrypter>, |
| write_seq: u64, |
| read_seq: u64, |
| encrypt_state: DirectionState, |
| decrypt_state: DirectionState, |
| } |
| |
| <span class="kw">impl </span>RecordLayer { |
| <span class="kw">pub fn </span>new() -> RecordLayer { |
| RecordLayer { |
| message_encrypter: MessageEncrypter::invalid(), |
| message_decrypter: MessageDecrypter::invalid(), |
| write_seq: <span class="number">0</span>, |
| read_seq: <span class="number">0</span>, |
| encrypt_state: DirectionState::Invalid, |
| decrypt_state: DirectionState::Invalid, |
| } |
| } |
| |
| <span class="kw">pub fn </span>is_encrypting(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.encrypt_state == DirectionState::Active |
| } |
| |
| <span class="kw">pub fn </span>is_decrypting(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.decrypt_state == DirectionState::Active |
| } |
| |
| <span class="doccomment">/// Prepare to use the given `MessageEncrypter` for future message encryption. |
| /// It is not used until you call `start_encrypting`. |
| </span><span class="kw">pub fn </span>prepare_message_encrypter(<span class="kw-2">&mut </span><span class="self">self</span>, cipher: Box<<span class="kw">dyn </span>MessageEncrypter>) { |
| <span class="self">self</span>.message_encrypter = cipher; |
| <span class="self">self</span>.write_seq = <span class="number">0</span>; |
| <span class="self">self</span>.encrypt_state = DirectionState::Prepared; |
| } |
| |
| <span class="doccomment">/// Prepare to use the given `MessageDecrypter` for future message decryption. |
| /// It is not used until you call `start_decrypting`. |
| </span><span class="kw">pub fn </span>prepare_message_decrypter(<span class="kw-2">&mut </span><span class="self">self</span>, cipher: Box<<span class="kw">dyn </span>MessageDecrypter>) { |
| <span class="self">self</span>.message_decrypter = cipher; |
| <span class="self">self</span>.read_seq = <span class="number">0</span>; |
| <span class="self">self</span>.decrypt_state = DirectionState::Prepared; |
| } |
| |
| <span class="doccomment">/// Start using the `MessageEncrypter` previously provided to the previous |
| /// call to `prepare_message_encrypter`. |
| </span><span class="kw">pub fn </span>start_encrypting(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="macro">debug_assert!</span>(<span class="self">self</span>.encrypt_state == DirectionState::Prepared); |
| <span class="self">self</span>.encrypt_state = DirectionState::Active; |
| } |
| |
| <span class="doccomment">/// Start using the `MessageDecrypter` previously provided to the previous |
| /// call to `prepare_message_decrypter`. |
| </span><span class="kw">pub fn </span>start_decrypting(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="macro">debug_assert!</span>(<span class="self">self</span>.decrypt_state == DirectionState::Prepared); |
| <span class="self">self</span>.decrypt_state = DirectionState::Active; |
| } |
| |
| <span class="doccomment">/// Set and start using the given `MessageEncrypter` for future outgoing |
| /// message encryption. |
| </span><span class="kw">pub fn </span>set_message_encrypter(<span class="kw-2">&mut </span><span class="self">self</span>, cipher: Box<<span class="kw">dyn </span>MessageEncrypter>) { |
| <span class="self">self</span>.prepare_message_encrypter(cipher); |
| <span class="self">self</span>.start_encrypting(); |
| } |
| |
| <span class="doccomment">/// Set and start using the given `MessageDecrypter` for future incoming |
| /// message decryption. |
| </span><span class="kw">pub fn </span>set_message_decrypter(<span class="kw-2">&mut </span><span class="self">self</span>, cipher: Box<<span class="kw">dyn </span>MessageDecrypter>) { |
| <span class="self">self</span>.prepare_message_decrypter(cipher); |
| <span class="self">self</span>.start_decrypting(); |
| } |
| |
| <span class="doccomment">/// Return true if the peer appears to getting close to encrypting |
| /// too many messages with this key. |
| /// |
| /// Perhaps if we send an alert well before their counter wraps, a |
| /// buggy peer won't make a terrible mistake here? |
| /// |
| /// Note that there's no reason to refuse to decrypt: the security |
| /// failure has already happened. |
| </span><span class="kw">pub fn </span>wants_close_before_decrypt(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.read_seq == SEQ_SOFT_LIMIT |
| } |
| |
| <span class="doccomment">/// Return true if we are getting close to encrypting too many |
| /// messages with our encryption key. |
| </span><span class="kw">pub fn </span>wants_close_before_encrypt(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.write_seq == SEQ_SOFT_LIMIT |
| } |
| |
| <span class="doccomment">/// Return true if we outright refuse to do anything with the |
| /// encryption key. |
| </span><span class="kw">pub fn </span>encrypt_exhausted(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.write_seq >= SEQ_HARD_LIMIT |
| } |
| |
| <span class="doccomment">/// Decrypt a TLS message. |
| /// |
| /// `encr` is a decoded message allegedly received from the peer. |
| /// If it can be decrypted, its decryption is returned. Otherwise, |
| /// an error is returned. |
| </span><span class="kw">pub fn </span>decrypt_incoming(<span class="kw-2">&mut </span><span class="self">self</span>, encr: Message) -> <span class="prelude-ty">Result</span><Message, TLSError> { |
| <span class="macro">debug_assert!</span>(<span class="self">self</span>.decrypt_state == DirectionState::Active); |
| <span class="kw">let </span>seq = <span class="self">self</span>.read_seq; |
| <span class="self">self</span>.read_seq += <span class="number">1</span>; |
| <span class="self">self</span>.message_decrypter |
| .decrypt(encr, seq) |
| } |
| |
| <span class="doccomment">/// Encrypt a TLS message. |
| /// |
| /// `plain` is a TLS message we'd like to send. This function |
| /// panics if the requisite keying material hasn't been established yet. |
| </span><span class="kw">pub fn </span>encrypt_outgoing(<span class="kw-2">&mut </span><span class="self">self</span>, plain: BorrowMessage) -> Message { |
| <span class="macro">debug_assert!</span>(<span class="self">self</span>.encrypt_state == DirectionState::Active); |
| <span class="macro">assert!</span>(!<span class="self">self</span>.encrypt_exhausted()); |
| <span class="kw">let </span>seq = <span class="self">self</span>.write_seq; |
| <span class="self">self</span>.write_seq += <span class="number">1</span>; |
| <span class="self">self</span>.message_encrypter |
| .encrypt(plain, seq) |
| .unwrap() |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="rustls" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
