| <!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/registry/src/github.com-1ecc6299db9ec823/rustls-0.19.1/src/key_schedule.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>key_schedule.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> |
| <span id="144">144</span> |
| <span id="145">145</span> |
| <span id="146">146</span> |
| <span id="147">147</span> |
| <span id="148">148</span> |
| <span id="149">149</span> |
| <span id="150">150</span> |
| <span id="151">151</span> |
| <span id="152">152</span> |
| <span id="153">153</span> |
| <span id="154">154</span> |
| <span id="155">155</span> |
| <span id="156">156</span> |
| <span id="157">157</span> |
| <span id="158">158</span> |
| <span id="159">159</span> |
| <span id="160">160</span> |
| <span id="161">161</span> |
| <span id="162">162</span> |
| <span id="163">163</span> |
| <span id="164">164</span> |
| <span id="165">165</span> |
| <span id="166">166</span> |
| <span id="167">167</span> |
| <span id="168">168</span> |
| <span id="169">169</span> |
| <span id="170">170</span> |
| <span id="171">171</span> |
| <span id="172">172</span> |
| <span id="173">173</span> |
| <span id="174">174</span> |
| <span id="175">175</span> |
| <span id="176">176</span> |
| <span id="177">177</span> |
| <span id="178">178</span> |
| <span id="179">179</span> |
| <span id="180">180</span> |
| <span id="181">181</span> |
| <span id="182">182</span> |
| <span id="183">183</span> |
| <span id="184">184</span> |
| <span id="185">185</span> |
| <span id="186">186</span> |
| <span id="187">187</span> |
| <span id="188">188</span> |
| <span id="189">189</span> |
| <span id="190">190</span> |
| <span id="191">191</span> |
| <span id="192">192</span> |
| <span id="193">193</span> |
| <span id="194">194</span> |
| <span id="195">195</span> |
| <span id="196">196</span> |
| <span id="197">197</span> |
| <span id="198">198</span> |
| <span id="199">199</span> |
| <span id="200">200</span> |
| <span id="201">201</span> |
| <span id="202">202</span> |
| <span id="203">203</span> |
| <span id="204">204</span> |
| <span id="205">205</span> |
| <span id="206">206</span> |
| <span id="207">207</span> |
| <span id="208">208</span> |
| <span id="209">209</span> |
| <span id="210">210</span> |
| <span id="211">211</span> |
| <span id="212">212</span> |
| <span id="213">213</span> |
| <span id="214">214</span> |
| <span id="215">215</span> |
| <span id="216">216</span> |
| <span id="217">217</span> |
| <span id="218">218</span> |
| <span id="219">219</span> |
| <span id="220">220</span> |
| <span id="221">221</span> |
| <span id="222">222</span> |
| <span id="223">223</span> |
| <span id="224">224</span> |
| <span id="225">225</span> |
| <span id="226">226</span> |
| <span id="227">227</span> |
| <span id="228">228</span> |
| <span id="229">229</span> |
| <span id="230">230</span> |
| <span id="231">231</span> |
| <span id="232">232</span> |
| <span id="233">233</span> |
| <span id="234">234</span> |
| <span id="235">235</span> |
| <span id="236">236</span> |
| <span id="237">237</span> |
| <span id="238">238</span> |
| <span id="239">239</span> |
| <span id="240">240</span> |
| <span id="241">241</span> |
| <span id="242">242</span> |
| <span id="243">243</span> |
| <span id="244">244</span> |
| <span id="245">245</span> |
| <span id="246">246</span> |
| <span id="247">247</span> |
| <span id="248">248</span> |
| <span id="249">249</span> |
| <span id="250">250</span> |
| <span id="251">251</span> |
| <span id="252">252</span> |
| <span id="253">253</span> |
| <span id="254">254</span> |
| <span id="255">255</span> |
| <span id="256">256</span> |
| <span id="257">257</span> |
| <span id="258">258</span> |
| <span id="259">259</span> |
| <span id="260">260</span> |
| <span id="261">261</span> |
| <span id="262">262</span> |
| <span id="263">263</span> |
| <span id="264">264</span> |
| <span id="265">265</span> |
| <span id="266">266</span> |
| <span id="267">267</span> |
| <span id="268">268</span> |
| <span id="269">269</span> |
| <span id="270">270</span> |
| <span id="271">271</span> |
| <span id="272">272</span> |
| <span id="273">273</span> |
| <span id="274">274</span> |
| <span id="275">275</span> |
| <span id="276">276</span> |
| <span id="277">277</span> |
| <span id="278">278</span> |
| <span id="279">279</span> |
| <span id="280">280</span> |
| <span id="281">281</span> |
| <span id="282">282</span> |
| <span id="283">283</span> |
| <span id="284">284</span> |
| <span id="285">285</span> |
| <span id="286">286</span> |
| <span id="287">287</span> |
| <span id="288">288</span> |
| <span id="289">289</span> |
| <span id="290">290</span> |
| <span id="291">291</span> |
| <span id="292">292</span> |
| <span id="293">293</span> |
| <span id="294">294</span> |
| <span id="295">295</span> |
| <span id="296">296</span> |
| <span id="297">297</span> |
| <span id="298">298</span> |
| <span id="299">299</span> |
| <span id="300">300</span> |
| <span id="301">301</span> |
| <span id="302">302</span> |
| <span id="303">303</span> |
| <span id="304">304</span> |
| <span id="305">305</span> |
| <span id="306">306</span> |
| <span id="307">307</span> |
| <span id="308">308</span> |
| <span id="309">309</span> |
| <span id="310">310</span> |
| <span id="311">311</span> |
| <span id="312">312</span> |
| <span id="313">313</span> |
| <span id="314">314</span> |
| <span id="315">315</span> |
| <span id="316">316</span> |
| <span id="317">317</span> |
| <span id="318">318</span> |
| <span id="319">319</span> |
| <span id="320">320</span> |
| <span id="321">321</span> |
| <span id="322">322</span> |
| <span id="323">323</span> |
| <span id="324">324</span> |
| <span id="325">325</span> |
| <span id="326">326</span> |
| <span id="327">327</span> |
| <span id="328">328</span> |
| <span id="329">329</span> |
| <span id="330">330</span> |
| <span id="331">331</span> |
| <span id="332">332</span> |
| <span id="333">333</span> |
| <span id="334">334</span> |
| <span id="335">335</span> |
| <span id="336">336</span> |
| <span id="337">337</span> |
| <span id="338">338</span> |
| <span id="339">339</span> |
| <span id="340">340</span> |
| <span id="341">341</span> |
| <span id="342">342</span> |
| <span id="343">343</span> |
| <span id="344">344</span> |
| <span id="345">345</span> |
| <span id="346">346</span> |
| <span id="347">347</span> |
| <span id="348">348</span> |
| <span id="349">349</span> |
| <span id="350">350</span> |
| <span id="351">351</span> |
| <span id="352">352</span> |
| <span id="353">353</span> |
| <span id="354">354</span> |
| <span id="355">355</span> |
| <span id="356">356</span> |
| <span id="357">357</span> |
| <span id="358">358</span> |
| <span id="359">359</span> |
| <span id="360">360</span> |
| <span id="361">361</span> |
| <span id="362">362</span> |
| <span id="363">363</span> |
| <span id="364">364</span> |
| <span id="365">365</span> |
| <span id="366">366</span> |
| <span id="367">367</span> |
| <span id="368">368</span> |
| <span id="369">369</span> |
| <span id="370">370</span> |
| <span id="371">371</span> |
| <span id="372">372</span> |
| <span id="373">373</span> |
| <span id="374">374</span> |
| <span id="375">375</span> |
| <span id="376">376</span> |
| <span id="377">377</span> |
| <span id="378">378</span> |
| <span id="379">379</span> |
| <span id="380">380</span> |
| <span id="381">381</span> |
| <span id="382">382</span> |
| <span id="383">383</span> |
| <span id="384">384</span> |
| <span id="385">385</span> |
| <span id="386">386</span> |
| <span id="387">387</span> |
| <span id="388">388</span> |
| <span id="389">389</span> |
| <span id="390">390</span> |
| <span id="391">391</span> |
| <span id="392">392</span> |
| <span id="393">393</span> |
| <span id="394">394</span> |
| <span id="395">395</span> |
| <span id="396">396</span> |
| <span id="397">397</span> |
| <span id="398">398</span> |
| <span id="399">399</span> |
| <span id="400">400</span> |
| <span id="401">401</span> |
| <span id="402">402</span> |
| <span id="403">403</span> |
| <span id="404">404</span> |
| <span id="405">405</span> |
| <span id="406">406</span> |
| <span id="407">407</span> |
| <span id="408">408</span> |
| <span id="409">409</span> |
| <span id="410">410</span> |
| <span id="411">411</span> |
| <span id="412">412</span> |
| <span id="413">413</span> |
| <span id="414">414</span> |
| <span id="415">415</span> |
| <span id="416">416</span> |
| <span id="417">417</span> |
| <span id="418">418</span> |
| <span id="419">419</span> |
| <span id="420">420</span> |
| <span id="421">421</span> |
| <span id="422">422</span> |
| <span id="423">423</span> |
| <span id="424">424</span> |
| <span id="425">425</span> |
| <span id="426">426</span> |
| <span id="427">427</span> |
| <span id="428">428</span> |
| <span id="429">429</span> |
| <span id="430">430</span> |
| <span id="431">431</span> |
| <span id="432">432</span> |
| <span id="433">433</span> |
| <span id="434">434</span> |
| <span id="435">435</span> |
| <span id="436">436</span> |
| <span id="437">437</span> |
| <span id="438">438</span> |
| <span id="439">439</span> |
| <span id="440">440</span> |
| <span id="441">441</span> |
| <span id="442">442</span> |
| <span id="443">443</span> |
| <span id="444">444</span> |
| <span id="445">445</span> |
| <span id="446">446</span> |
| <span id="447">447</span> |
| <span id="448">448</span> |
| <span id="449">449</span> |
| <span id="450">450</span> |
| <span id="451">451</span> |
| <span id="452">452</span> |
| <span id="453">453</span> |
| <span id="454">454</span> |
| <span id="455">455</span> |
| <span id="456">456</span> |
| <span id="457">457</span> |
| <span id="458">458</span> |
| <span id="459">459</span> |
| <span id="460">460</span> |
| <span id="461">461</span> |
| <span id="462">462</span> |
| <span id="463">463</span> |
| <span id="464">464</span> |
| <span id="465">465</span> |
| <span id="466">466</span> |
| <span id="467">467</span> |
| <span id="468">468</span> |
| <span id="469">469</span> |
| <span id="470">470</span> |
| <span id="471">471</span> |
| <span id="472">472</span> |
| <span id="473">473</span> |
| <span id="474">474</span> |
| <span id="475">475</span> |
| <span id="476">476</span> |
| <span id="477">477</span> |
| <span id="478">478</span> |
| <span id="479">479</span> |
| <span id="480">480</span> |
| <span id="481">481</span> |
| <span id="482">482</span> |
| <span id="483">483</span> |
| <span id="484">484</span> |
| <span id="485">485</span> |
| <span id="486">486</span> |
| <span id="487">487</span> |
| <span id="488">488</span> |
| <span id="489">489</span> |
| <span id="490">490</span> |
| <span id="491">491</span> |
| <span id="492">492</span> |
| <span id="493">493</span> |
| <span id="494">494</span> |
| <span id="495">495</span> |
| <span id="496">496</span> |
| <span id="497">497</span> |
| <span id="498">498</span> |
| <span id="499">499</span> |
| <span id="500">500</span> |
| <span id="501">501</span> |
| <span id="502">502</span> |
| <span id="503">503</span> |
| <span id="504">504</span> |
| <span id="505">505</span> |
| <span id="506">506</span> |
| <span id="507">507</span> |
| <span id="508">508</span> |
| <span id="509">509</span> |
| <span id="510">510</span> |
| <span id="511">511</span> |
| <span id="512">512</span> |
| <span id="513">513</span> |
| <span id="514">514</span> |
| <span id="515">515</span> |
| <span id="516">516</span> |
| <span id="517">517</span> |
| <span id="518">518</span> |
| <span id="519">519</span> |
| <span id="520">520</span> |
| <span id="521">521</span> |
| <span id="522">522</span> |
| <span id="523">523</span> |
| <span id="524">524</span> |
| <span id="525">525</span> |
| <span id="526">526</span> |
| <span id="527">527</span> |
| <span id="528">528</span> |
| <span id="529">529</span> |
| <span id="530">530</span> |
| <span id="531">531</span> |
| <span id="532">532</span> |
| <span id="533">533</span> |
| <span id="534">534</span> |
| <span id="535">535</span> |
| <span id="536">536</span> |
| <span id="537">537</span> |
| <span id="538">538</span> |
| <span id="539">539</span> |
| <span id="540">540</span> |
| <span id="541">541</span> |
| <span id="542">542</span> |
| <span id="543">543</span> |
| <span id="544">544</span> |
| <span id="545">545</span> |
| <span id="546">546</span> |
| <span id="547">547</span> |
| <span id="548">548</span> |
| <span id="549">549</span> |
| <span id="550">550</span> |
| <span id="551">551</span> |
| <span id="552">552</span> |
| <span id="553">553</span> |
| <span id="554">554</span> |
| <span id="555">555</span> |
| <span id="556">556</span> |
| <span id="557">557</span> |
| <span id="558">558</span> |
| <span id="559">559</span> |
| <span id="560">560</span> |
| <span id="561">561</span> |
| <span id="562">562</span> |
| <span id="563">563</span> |
| <span id="564">564</span> |
| <span id="565">565</span> |
| <span id="566">566</span> |
| <span id="567">567</span> |
| <span id="568">568</span> |
| <span id="569">569</span> |
| <span id="570">570</span> |
| <span id="571">571</span> |
| <span id="572">572</span> |
| <span id="573">573</span> |
| <span id="574">574</span> |
| <span id="575">575</span> |
| <span id="576">576</span> |
| <span id="577">577</span> |
| <span id="578">578</span> |
| <span id="579">579</span> |
| <span id="580">580</span> |
| <span id="581">581</span> |
| <span id="582">582</span> |
| <span id="583">583</span> |
| <span id="584">584</span> |
| <span id="585">585</span> |
| <span id="586">586</span> |
| <span id="587">587</span> |
| <span id="588">588</span> |
| <span id="589">589</span> |
| <span id="590">590</span> |
| <span id="591">591</span> |
| <span id="592">592</span> |
| <span id="593">593</span> |
| <span id="594">594</span> |
| <span id="595">595</span> |
| <span id="596">596</span> |
| <span id="597">597</span> |
| <span id="598">598</span> |
| <span id="599">599</span> |
| <span id="600">600</span> |
| <span id="601">601</span> |
| <span id="602">602</span> |
| <span id="603">603</span> |
| <span id="604">604</span> |
| <span id="605">605</span> |
| <span id="606">606</span> |
| <span id="607">607</span> |
| <span id="608">608</span> |
| <span id="609">609</span> |
| <span id="610">610</span> |
| <span id="611">611</span> |
| <span id="612">612</span> |
| <span id="613">613</span> |
| <span id="614">614</span> |
| <span id="615">615</span> |
| <span id="616">616</span> |
| <span id="617">617</span> |
| <span id="618">618</span> |
| <span id="619">619</span> |
| <span id="620">620</span> |
| <span id="621">621</span> |
| <span id="622">622</span> |
| <span id="623">623</span> |
| <span id="624">624</span> |
| <span id="625">625</span> |
| <span id="626">626</span> |
| <span id="627">627</span> |
| <span id="628">628</span> |
| <span id="629">629</span> |
| <span id="630">630</span> |
| <span id="631">631</span> |
| <span id="632">632</span> |
| <span id="633">633</span> |
| <span id="634">634</span> |
| <span id="635">635</span> |
| <span id="636">636</span> |
| <span id="637">637</span> |
| <span id="638">638</span> |
| <span id="639">639</span> |
| <span id="640">640</span> |
| <span id="641">641</span> |
| <span id="642">642</span> |
| <span id="643">643</span> |
| <span id="644">644</span> |
| <span id="645">645</span> |
| <span id="646">646</span> |
| <span id="647">647</span> |
| <span id="648">648</span> |
| <span id="649">649</span> |
| <span id="650">650</span> |
| <span id="651">651</span> |
| <span id="652">652</span> |
| <span id="653">653</span> |
| <span id="654">654</span> |
| <span id="655">655</span> |
| <span id="656">656</span> |
| <span id="657">657</span> |
| <span id="658">658</span> |
| <span id="659">659</span> |
| <span id="660">660</span> |
| <span id="661">661</span> |
| <span id="662">662</span> |
| <span id="663">663</span> |
| <span id="664">664</span> |
| <span id="665">665</span> |
| <span id="666">666</span> |
| <span id="667">667</span> |
| <span id="668">668</span> |
| <span id="669">669</span> |
| <span id="670">670</span> |
| <span id="671">671</span> |
| <span id="672">672</span> |
| <span id="673">673</span> |
| <span id="674">674</span> |
| <span id="675">675</span> |
| <span id="676">676</span> |
| <span id="677">677</span> |
| <span id="678">678</span> |
| <span id="679">679</span> |
| <span id="680">680</span> |
| <span id="681">681</span> |
| <span id="682">682</span> |
| <span id="683">683</span> |
| <span id="684">684</span> |
| <span id="685">685</span> |
| <span id="686">686</span> |
| <span id="687">687</span> |
| <span id="688">688</span> |
| <span id="689">689</span> |
| <span id="690">690</span> |
| <span id="691">691</span> |
| <span id="692">692</span> |
| <span id="693">693</span> |
| <span id="694">694</span> |
| <span id="695">695</span> |
| <span id="696">696</span> |
| <span id="697">697</span> |
| <span id="698">698</span> |
| <span id="699">699</span> |
| <span id="700">700</span> |
| <span id="701">701</span> |
| <span id="702">702</span> |
| <span id="703">703</span> |
| <span id="704">704</span> |
| <span id="705">705</span> |
| <span id="706">706</span> |
| <span id="707">707</span> |
| <span id="708">708</span> |
| <span id="709">709</span> |
| <span id="710">710</span> |
| </pre><pre class="rust"><code><span class="kw">use </span><span class="kw">crate</span>::cipher::{Iv, IvLen}; |
| <span class="kw">use </span><span class="kw">crate</span>::error::TLSError; |
| <span class="kw">use </span><span class="kw">crate</span>::msgs::base::PayloadU8; |
| <span class="kw">use </span><span class="kw">crate</span>::KeyLog; |
| <span class="doccomment">/// Key schedule maintenance for TLS1.3 |
| </span><span class="kw">use </span>ring::{ |
| aead, digest, |
| hkdf::{<span class="self">self</span>, KeyType <span class="kw">as _</span>}, |
| hmac, |
| }; |
| |
| <span class="doccomment">/// The kinds of secret we can extract from `KeySchedule`. |
| </span><span class="attribute">#[derive(Debug, Clone, Copy, PartialEq)] |
| </span><span class="kw">enum </span>SecretKind { |
| ResumptionPSKBinderKey, |
| ClientEarlyTrafficSecret, |
| ClientHandshakeTrafficSecret, |
| ServerHandshakeTrafficSecret, |
| ClientApplicationTrafficSecret, |
| ServerApplicationTrafficSecret, |
| ExporterMasterSecret, |
| ResumptionMasterSecret, |
| DerivedSecret, |
| } |
| |
| <span class="kw">impl </span>SecretKind { |
| <span class="kw">fn </span>to_bytes(<span class="self">self</span>) -> <span class="kw-2">&</span><span class="lifetime">'static </span>[u8] { |
| <span class="kw">match </span><span class="self">self </span>{ |
| SecretKind::ResumptionPSKBinderKey => <span class="string">b"res binder"</span>, |
| SecretKind::ClientEarlyTrafficSecret => <span class="string">b"c e traffic"</span>, |
| SecretKind::ClientHandshakeTrafficSecret => <span class="string">b"c hs traffic"</span>, |
| SecretKind::ServerHandshakeTrafficSecret => <span class="string">b"s hs traffic"</span>, |
| SecretKind::ClientApplicationTrafficSecret => <span class="string">b"c ap traffic"</span>, |
| SecretKind::ServerApplicationTrafficSecret => <span class="string">b"s ap traffic"</span>, |
| SecretKind::ExporterMasterSecret => <span class="string">b"exp master"</span>, |
| SecretKind::ResumptionMasterSecret => <span class="string">b"res master"</span>, |
| SecretKind::DerivedSecret => <span class="string">b"derived"</span>, |
| } |
| } |
| |
| <span class="kw">fn </span>log_label(<span class="self">self</span>) -> <span class="prelude-ty">Option</span><<span class="kw-2">&</span><span class="lifetime">'static </span>str> { |
| <span class="kw">use </span><span class="self">self</span>::SecretKind::<span class="kw-2">*</span>; |
| <span class="prelude-val">Some</span>(<span class="kw">match </span><span class="self">self </span>{ |
| ClientEarlyTrafficSecret => <span class="string">"CLIENT_EARLY_TRAFFIC_SECRET"</span>, |
| ClientHandshakeTrafficSecret => <span class="string">"CLIENT_HANDSHAKE_TRAFFIC_SECRET"</span>, |
| ServerHandshakeTrafficSecret => <span class="string">"SERVER_HANDSHAKE_TRAFFIC_SECRET"</span>, |
| ClientApplicationTrafficSecret => <span class="string">"CLIENT_TRAFFIC_SECRET_0"</span>, |
| ServerApplicationTrafficSecret => <span class="string">"SERVER_TRAFFIC_SECRET_0"</span>, |
| ExporterMasterSecret => <span class="string">"EXPORTER_SECRET"</span>, |
| <span class="kw">_ </span>=> { |
| <span class="kw">return </span><span class="prelude-val">None</span>; |
| } |
| }) |
| } |
| } |
| |
| <span class="doccomment">/// This is the TLS1.3 key schedule. It stores the current secret and |
| /// the type of hash. This isn't used directly; but only through the |
| /// typestates. |
| </span><span class="kw">struct </span>KeySchedule { |
| current: hkdf::Prk, |
| algorithm: ring::hkdf::Algorithm, |
| } |
| |
| <span class="comment">// We express the state of a contained KeySchedule using these |
| // typestates. This means we can write code that cannot accidentally |
| // (eg) encrypt application data using a KeySchedule solely constructed |
| // with an empty or trivial secret, or extract the wrong kind of secrets |
| // at a given point. |
| |
| </span><span class="doccomment">/// KeySchedule for early data stage. |
| </span><span class="kw">pub struct </span>KeyScheduleEarly { |
| ks: KeySchedule, |
| } |
| |
| <span class="kw">impl </span>KeyScheduleEarly { |
| <span class="kw">pub fn </span>new(algorithm: hkdf::Algorithm, secret: <span class="kw-2">&</span>[u8]) -> KeyScheduleEarly { |
| KeyScheduleEarly { |
| ks: KeySchedule::new(algorithm, secret), |
| } |
| } |
| |
| <span class="kw">pub fn </span>client_early_traffic_secret( |
| <span class="kw-2">&</span><span class="self">self</span>, |
| hs_hash: <span class="kw-2">&</span>[u8], |
| key_log: <span class="kw-2">&</span><span class="kw">dyn </span>KeyLog, |
| client_random: <span class="kw-2">&</span>[u8; <span class="number">32</span>], |
| ) -> hkdf::Prk { |
| <span class="self">self</span>.ks.derive_logged_secret( |
| SecretKind::ClientEarlyTrafficSecret, |
| hs_hash, |
| key_log, |
| client_random, |
| ) |
| } |
| |
| <span class="kw">pub fn </span>resumption_psk_binder_key_and_sign_verify_data(<span class="kw-2">&</span><span class="self">self</span>, hs_hash: <span class="kw-2">&</span>[u8]) -> Vec<u8> { |
| <span class="kw">let </span>resumption_psk_binder_key = <span class="self">self |
| </span>.ks |
| .derive_for_empty_hash(SecretKind::ResumptionPSKBinderKey); |
| <span class="self">self</span>.ks |
| .sign_verify_data(<span class="kw-2">&</span>resumption_psk_binder_key, hs_hash) |
| } |
| |
| <span class="kw">pub fn </span>into_handshake(<span class="kw-2">mut </span><span class="self">self</span>, secret: <span class="kw-2">&</span>[u8]) -> KeyScheduleHandshake { |
| <span class="self">self</span>.ks.input_secret(secret); |
| KeyScheduleHandshake { |
| ks: <span class="self">self</span>.ks, |
| current_client_traffic_secret: <span class="prelude-val">None</span>, |
| current_server_traffic_secret: <span class="prelude-val">None</span>, |
| } |
| } |
| } |
| |
| <span class="doccomment">/// KeySchedule for skipping early data stage. No secrets can be extracted |
| /// (since there are none), but the handshake secret can be input. |
| </span><span class="kw">pub struct </span>KeyScheduleNonSecret { |
| ks: KeySchedule, |
| } |
| |
| <span class="kw">impl </span>KeyScheduleNonSecret { |
| <span class="kw">pub fn </span>new(algorithm: hkdf::Algorithm) -> KeyScheduleNonSecret { |
| KeyScheduleNonSecret { |
| ks: KeySchedule::new_with_empty_secret(algorithm), |
| } |
| } |
| |
| <span class="kw">pub fn </span>into_handshake(<span class="kw-2">mut </span><span class="self">self</span>, secret: <span class="kw-2">&</span>[u8]) -> KeyScheduleHandshake { |
| <span class="self">self</span>.ks.input_secret(secret); |
| KeyScheduleHandshake { |
| ks: <span class="self">self</span>.ks, |
| current_client_traffic_secret: <span class="prelude-val">None</span>, |
| current_server_traffic_secret: <span class="prelude-val">None</span>, |
| } |
| } |
| } |
| |
| <span class="doccomment">/// KeySchedule during handshake. |
| </span><span class="kw">pub struct </span>KeyScheduleHandshake { |
| ks: KeySchedule, |
| current_client_traffic_secret: <span class="prelude-ty">Option</span><hkdf::Prk>, |
| current_server_traffic_secret: <span class="prelude-ty">Option</span><hkdf::Prk>, |
| } |
| |
| <span class="kw">impl </span>KeyScheduleHandshake { |
| <span class="kw">pub fn </span>client_handshake_traffic_secret( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| hs_hash: <span class="kw-2">&</span>[u8], |
| key_log: <span class="kw-2">&</span><span class="kw">dyn </span>KeyLog, |
| client_random: <span class="kw-2">&</span>[u8; <span class="number">32</span>], |
| ) -> hkdf::Prk { |
| <span class="kw">let </span>secret = <span class="self">self</span>.ks.derive_logged_secret( |
| SecretKind::ClientHandshakeTrafficSecret, |
| hs_hash, |
| key_log, |
| client_random, |
| ); |
| <span class="self">self</span>.current_client_traffic_secret = <span class="prelude-val">Some</span>(secret.clone()); |
| secret |
| } |
| |
| <span class="kw">pub fn </span>server_handshake_traffic_secret( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| hs_hash: <span class="kw-2">&</span>[u8], |
| key_log: <span class="kw-2">&</span><span class="kw">dyn </span>KeyLog, |
| client_random: <span class="kw-2">&</span>[u8; <span class="number">32</span>], |
| ) -> hkdf::Prk { |
| <span class="kw">let </span>secret = <span class="self">self</span>.ks.derive_logged_secret( |
| SecretKind::ServerHandshakeTrafficSecret, |
| hs_hash, |
| key_log, |
| client_random, |
| ); |
| <span class="self">self</span>.current_server_traffic_secret = <span class="prelude-val">Some</span>(secret.clone()); |
| secret |
| } |
| |
| <span class="kw">pub fn </span>sign_server_finish(<span class="kw-2">&</span><span class="self">self</span>, hs_hash: <span class="kw-2">&</span>[u8]) -> Vec<u8> { |
| <span class="self">self</span>.ks.sign_finish( |
| <span class="self">self</span>.current_server_traffic_secret |
| .as_ref() |
| .unwrap(), |
| hs_hash, |
| ) |
| } |
| |
| <span class="kw">pub fn </span>into_traffic_with_client_finished_pending( |
| <span class="kw-2">mut </span><span class="self">self</span>, |
| ) -> KeyScheduleTrafficWithClientFinishedPending { |
| <span class="self">self</span>.ks.input_empty(); |
| KeyScheduleTrafficWithClientFinishedPending { |
| ks: <span class="self">self</span>.ks, |
| handshake_client_traffic_secret: <span class="self">self |
| </span>.current_client_traffic_secret |
| .unwrap(), |
| current_client_traffic_secret: <span class="prelude-val">None</span>, |
| current_server_traffic_secret: <span class="prelude-val">None</span>, |
| current_exporter_secret: <span class="prelude-val">None</span>, |
| } |
| } |
| } |
| |
| <span class="doccomment">/// KeySchedule during traffic stage, retaining the ability to calculate the client's |
| /// finished verify_data, and incrementally generate the first traffic keys. |
| </span><span class="kw">pub struct </span>KeyScheduleTrafficWithClientFinishedPending { |
| ks: KeySchedule, |
| handshake_client_traffic_secret: hkdf::Prk, |
| current_client_traffic_secret: <span class="prelude-ty">Option</span><hkdf::Prk>, |
| current_server_traffic_secret: <span class="prelude-ty">Option</span><hkdf::Prk>, |
| current_exporter_secret: <span class="prelude-ty">Option</span><hkdf::Prk>, |
| } |
| |
| <span class="kw">impl </span>KeyScheduleTrafficWithClientFinishedPending { |
| <span class="kw">pub fn </span>sign_client_finish(<span class="kw-2">&</span><span class="self">self</span>, hs_hash: <span class="kw-2">&</span>[u8]) -> Vec<u8> { |
| <span class="self">self</span>.ks |
| .sign_finish(<span class="kw-2">&</span><span class="self">self</span>.handshake_client_traffic_secret, hs_hash) |
| } |
| |
| <span class="kw">pub fn </span>server_application_traffic_secret( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| hs_hash: <span class="kw-2">&</span>[u8], |
| key_log: <span class="kw-2">&</span><span class="kw">dyn </span>KeyLog, |
| client_random: <span class="kw-2">&</span>[u8; <span class="number">32</span>], |
| ) -> hkdf::Prk { |
| <span class="kw">let </span>secret = <span class="self">self</span>.ks.derive_logged_secret( |
| SecretKind::ServerApplicationTrafficSecret, |
| hs_hash, |
| key_log, |
| client_random, |
| ); |
| <span class="self">self</span>.current_server_traffic_secret = <span class="prelude-val">Some</span>(secret.clone()); |
| secret |
| } |
| |
| <span class="kw">pub fn </span>client_application_traffic_secret( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| hs_hash: <span class="kw-2">&</span>[u8], |
| key_log: <span class="kw-2">&</span><span class="kw">dyn </span>KeyLog, |
| client_random: <span class="kw-2">&</span>[u8; <span class="number">32</span>], |
| ) -> hkdf::Prk { |
| <span class="kw">let </span>secret = <span class="self">self</span>.ks.derive_logged_secret( |
| SecretKind::ClientApplicationTrafficSecret, |
| hs_hash, |
| key_log, |
| client_random, |
| ); |
| <span class="self">self</span>.current_client_traffic_secret = <span class="prelude-val">Some</span>(secret.clone()); |
| secret |
| } |
| |
| <span class="kw">pub fn </span>exporter_master_secret( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| hs_hash: <span class="kw-2">&</span>[u8], |
| key_log: <span class="kw-2">&</span><span class="kw">dyn </span>KeyLog, |
| client_random: <span class="kw-2">&</span>[u8; <span class="number">32</span>], |
| ) { |
| <span class="kw">let </span>secret = <span class="self">self</span>.ks.derive_logged_secret( |
| SecretKind::ExporterMasterSecret, |
| hs_hash, |
| key_log, |
| client_random, |
| ); |
| <span class="self">self</span>.current_exporter_secret = <span class="prelude-val">Some</span>(secret); |
| } |
| |
| <span class="kw">pub fn </span>into_traffic(<span class="self">self</span>) -> KeyScheduleTraffic { |
| KeyScheduleTraffic { |
| ks: <span class="self">self</span>.ks, |
| current_client_traffic_secret: <span class="self">self |
| </span>.current_client_traffic_secret |
| .unwrap(), |
| current_server_traffic_secret: <span class="self">self |
| </span>.current_server_traffic_secret |
| .unwrap(), |
| current_exporter_secret: <span class="self">self</span>.current_exporter_secret.unwrap(), |
| } |
| } |
| } |
| |
| <span class="doccomment">/// KeySchedule during traffic stage. All traffic & exporter keys are guaranteed |
| /// to be available. |
| </span><span class="kw">pub struct </span>KeyScheduleTraffic { |
| ks: KeySchedule, |
| current_client_traffic_secret: hkdf::Prk, |
| current_server_traffic_secret: hkdf::Prk, |
| current_exporter_secret: hkdf::Prk, |
| } |
| |
| <span class="kw">impl </span>KeyScheduleTraffic { |
| <span class="kw">pub fn </span>next_server_application_traffic_secret(<span class="kw-2">&mut </span><span class="self">self</span>) -> hkdf::Prk { |
| <span class="kw">let </span>secret = <span class="self">self |
| </span>.ks |
| .derive_next(<span class="kw-2">&</span><span class="self">self</span>.current_server_traffic_secret); |
| <span class="self">self</span>.current_server_traffic_secret = secret.clone(); |
| secret |
| } |
| |
| <span class="kw">pub fn </span>next_client_application_traffic_secret(<span class="kw-2">&mut </span><span class="self">self</span>) -> hkdf::Prk { |
| <span class="kw">let </span>secret = <span class="self">self |
| </span>.ks |
| .derive_next(<span class="kw-2">&</span><span class="self">self</span>.current_client_traffic_secret); |
| <span class="self">self</span>.current_client_traffic_secret = secret.clone(); |
| secret |
| } |
| |
| <span class="kw">pub fn </span>resumption_master_secret_and_derive_ticket_psk( |
| <span class="kw-2">&</span><span class="self">self</span>, |
| hs_hash: <span class="kw-2">&</span>[u8], |
| nonce: <span class="kw-2">&</span>[u8], |
| ) -> Vec<u8> { |
| <span class="kw">let </span>resumption_master_secret = <span class="self">self</span>.ks.derive( |
| <span class="self">self</span>.ks.algorithm(), |
| SecretKind::ResumptionMasterSecret, |
| hs_hash, |
| ); |
| <span class="self">self</span>.ks |
| .derive_ticket_psk(<span class="kw-2">&</span>resumption_master_secret, nonce) |
| } |
| |
| <span class="kw">pub fn </span>export_keying_material( |
| <span class="kw-2">&</span><span class="self">self</span>, |
| out: <span class="kw-2">&mut </span>[u8], |
| label: <span class="kw-2">&</span>[u8], |
| context: <span class="prelude-ty">Option</span><<span class="kw-2">&</span>[u8]>, |
| ) -> <span class="prelude-ty">Result</span><(), TLSError> { |
| <span class="self">self</span>.ks |
| .export_keying_material(<span class="kw-2">&</span><span class="self">self</span>.current_exporter_secret, out, label, context) |
| } |
| } |
| |
| <span class="kw">impl </span>KeySchedule { |
| <span class="kw">fn </span>new(algorithm: hkdf::Algorithm, secret: <span class="kw-2">&</span>[u8]) -> KeySchedule { |
| <span class="kw">let </span>zeroes = [<span class="number">0u8</span>; digest::MAX_OUTPUT_LEN]; |
| <span class="kw">let </span>zeroes = <span class="kw-2">&</span>zeroes[..algorithm.len()]; |
| <span class="kw">let </span>salt = hkdf::Salt::new(algorithm, <span class="kw-2">&</span>zeroes); |
| KeySchedule { |
| current: salt.extract(secret), |
| algorithm, |
| } |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>algorithm(<span class="kw-2">&</span><span class="self">self</span>) -> hkdf::Algorithm { |
| <span class="self">self</span>.algorithm |
| } |
| |
| <span class="kw">fn </span>new_with_empty_secret(algorithm: hkdf::Algorithm) -> KeySchedule { |
| <span class="kw">let </span>zeroes = [<span class="number">0u8</span>; digest::MAX_OUTPUT_LEN]; |
| <span class="self">Self</span>::new(algorithm, <span class="kw-2">&</span>zeroes[..algorithm.len()]) |
| } |
| |
| <span class="doccomment">/// Input the empty secret. |
| </span><span class="kw">fn </span>input_empty(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="kw">let </span>zeroes = [<span class="number">0u8</span>; digest::MAX_OUTPUT_LEN]; |
| <span class="self">self</span>.input_secret(<span class="kw-2">&</span>zeroes[..<span class="self">self</span>.algorithm.len()]); |
| } |
| |
| <span class="doccomment">/// Input the given secret. |
| </span><span class="kw">fn </span>input_secret(<span class="kw-2">&mut </span><span class="self">self</span>, secret: <span class="kw-2">&</span>[u8]) { |
| <span class="kw">let </span>salt: hkdf::Salt = <span class="self">self</span>.derive_for_empty_hash(SecretKind::DerivedSecret); |
| <span class="self">self</span>.current = salt.extract(secret); |
| } |
| |
| <span class="doccomment">/// Derive a secret of given `kind`, using current handshake hash `hs_hash`. |
| </span><span class="kw">fn </span>derive<T, L>(<span class="kw-2">&</span><span class="self">self</span>, key_type: L, kind: SecretKind, hs_hash: <span class="kw-2">&</span>[u8]) -> T |
| <span class="kw">where |
| </span>T: <span class="kw">for</span><<span class="lifetime">'a</span>> From<hkdf::Okm<<span class="lifetime">'a</span>, L>>, |
| L: hkdf::KeyType, |
| { |
| hkdf_expand(<span class="kw-2">&</span><span class="self">self</span>.current, key_type, kind.to_bytes(), hs_hash) |
| } |
| |
| <span class="kw">fn </span>derive_logged_secret( |
| <span class="kw-2">&</span><span class="self">self</span>, |
| kind: SecretKind, |
| hs_hash: <span class="kw-2">&</span>[u8], |
| key_log: <span class="kw-2">&</span><span class="kw">dyn </span>KeyLog, |
| client_random: <span class="kw-2">&</span>[u8; <span class="number">32</span>], |
| ) -> hkdf::Prk { |
| <span class="kw">let </span>log_label = kind |
| .log_label() |
| .expect(<span class="string">"not a loggable secret"</span>); |
| <span class="kw">if </span>key_log.will_log(log_label) { |
| <span class="kw">let </span>secret = <span class="self">self |
| </span>.derive::<PayloadU8, <span class="kw">_</span>>(PayloadU8Len(<span class="self">self</span>.algorithm.len()), kind, hs_hash) |
| .into_inner(); |
| key_log.log(log_label, client_random, <span class="kw-2">&</span>secret); |
| } |
| <span class="self">self</span>.derive(<span class="self">self</span>.algorithm, kind, hs_hash) |
| } |
| |
| <span class="doccomment">/// Derive a secret of given `kind` using the hash of the empty string |
| /// for the handshake hash. Useful only for |
| /// `SecretKind::ResumptionPSKBinderKey` and |
| /// `SecretKind::DerivedSecret`. |
| </span><span class="kw">fn </span>derive_for_empty_hash<T>(<span class="kw-2">&</span><span class="self">self</span>, kind: SecretKind) -> T |
| <span class="kw">where |
| </span>T: <span class="kw">for</span><<span class="lifetime">'a</span>> From<hkdf::Okm<<span class="lifetime">'a</span>, hkdf::Algorithm>>, |
| { |
| <span class="kw">let </span>digest_alg = <span class="self">self |
| </span>.algorithm |
| .hmac_algorithm() |
| .digest_algorithm(); |
| <span class="kw">let </span>empty_hash = digest::digest(digest_alg, <span class="kw-2">&</span>[]); |
| <span class="self">self</span>.derive(<span class="self">self</span>.algorithm, kind, empty_hash.as_ref()) |
| } |
| |
| <span class="doccomment">/// Sign the finished message consisting of `hs_hash` using a current |
| /// traffic secret. |
| </span><span class="kw">fn </span>sign_finish(<span class="kw-2">&</span><span class="self">self</span>, base_key: <span class="kw-2">&</span>hkdf::Prk, hs_hash: <span class="kw-2">&</span>[u8]) -> Vec<u8> { |
| <span class="self">self</span>.sign_verify_data(base_key, hs_hash) |
| } |
| |
| <span class="doccomment">/// Sign the finished message consisting of `hs_hash` using the key material |
| /// `base_key`. |
| </span><span class="kw">fn </span>sign_verify_data(<span class="kw-2">&</span><span class="self">self</span>, base_key: <span class="kw-2">&</span>hkdf::Prk, hs_hash: <span class="kw-2">&</span>[u8]) -> Vec<u8> { |
| <span class="kw">let </span>hmac_alg = <span class="self">self</span>.algorithm.hmac_algorithm(); |
| <span class="kw">let </span>hmac_key = hkdf_expand(base_key, hmac_alg, <span class="string">b"finished"</span>, <span class="kw-2">&</span>[]); |
| hmac::sign(<span class="kw-2">&</span>hmac_key, hs_hash) |
| .as_ref() |
| .to_vec() |
| } |
| |
| <span class="doccomment">/// Derive the next application traffic secret, returning it. |
| </span><span class="kw">fn </span>derive_next(<span class="kw-2">&</span><span class="self">self</span>, base_key: <span class="kw-2">&</span>hkdf::Prk) -> hkdf::Prk { |
| hkdf_expand(<span class="kw-2">&</span>base_key, <span class="self">self</span>.algorithm, <span class="string">b"traffic upd"</span>, <span class="kw-2">&</span>[]) |
| } |
| |
| <span class="doccomment">/// Derive the PSK to use given a resumption_master_secret and |
| /// ticket_nonce. |
| </span><span class="kw">fn </span>derive_ticket_psk(<span class="kw-2">&</span><span class="self">self</span>, rms: <span class="kw-2">&</span>hkdf::Prk, nonce: <span class="kw-2">&</span>[u8]) -> Vec<u8> { |
| <span class="kw">let </span>payload: PayloadU8 = hkdf_expand( |
| rms, |
| PayloadU8Len(<span class="self">self</span>.algorithm.len()), |
| <span class="string">b"resumption"</span>, |
| nonce, |
| ); |
| payload.into_inner() |
| } |
| |
| <span class="kw">fn </span>export_keying_material( |
| <span class="kw-2">&</span><span class="self">self</span>, |
| current_exporter_secret: <span class="kw-2">&</span>hkdf::Prk, |
| out: <span class="kw-2">&mut </span>[u8], |
| label: <span class="kw-2">&</span>[u8], |
| context: <span class="prelude-ty">Option</span><<span class="kw-2">&</span>[u8]>, |
| ) -> <span class="prelude-ty">Result</span><(), TLSError> { |
| <span class="kw">let </span>digest_alg = <span class="self">self |
| </span>.algorithm |
| .hmac_algorithm() |
| .digest_algorithm(); |
| |
| <span class="kw">let </span>h_empty = digest::digest(digest_alg, <span class="kw-2">&</span>[]); |
| <span class="kw">let </span>secret: hkdf::Prk = hkdf_expand( |
| current_exporter_secret, |
| <span class="self">self</span>.algorithm, |
| label, |
| h_empty.as_ref(), |
| ); |
| |
| <span class="kw">let </span>h_context = digest::digest(digest_alg, context.unwrap_or(<span class="kw-2">&</span>[])); |
| |
| <span class="comment">// TODO: Test what happens when this fails |
| </span>hkdf_expand_info( |
| <span class="kw-2">&</span>secret, |
| PayloadU8Len(out.len()), |
| <span class="string">b"exporter"</span>, |
| h_context.as_ref(), |
| |okm| okm.fill(out), |
| ) |
| .map_err(|<span class="kw">_</span>| TLSError::General(<span class="string">"exporting too much"</span>.to_string())) |
| } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>hkdf_expand<T, L>(secret: <span class="kw-2">&</span>hkdf::Prk, key_type: L, label: <span class="kw-2">&</span>[u8], context: <span class="kw-2">&</span>[u8]) -> T |
| <span class="kw">where |
| </span>T: <span class="kw">for</span><<span class="lifetime">'a</span>> From<hkdf::Okm<<span class="lifetime">'a</span>, L>>, |
| L: hkdf::KeyType, |
| { |
| hkdf_expand_info(secret, key_type, label, context, |okm| okm.into()) |
| } |
| |
| <span class="kw">fn </span>hkdf_expand_info<F, T, L>( |
| secret: <span class="kw-2">&</span>hkdf::Prk, |
| key_type: L, |
| label: <span class="kw-2">&</span>[u8], |
| context: <span class="kw-2">&</span>[u8], |
| f: F, |
| ) -> T |
| <span class="kw">where |
| </span>F: <span class="kw">for</span><<span class="lifetime">'b</span>> FnOnce(hkdf::Okm<<span class="lifetime">'b</span>, L>) -> T, |
| L: hkdf::KeyType, |
| { |
| <span class="kw">const </span>LABEL_PREFIX: <span class="kw-2">&</span>[u8] = <span class="string">b"tls13 "</span>; |
| |
| <span class="kw">let </span>output_len = u16::to_be_bytes(key_type.len() <span class="kw">as </span>u16); |
| <span class="kw">let </span>label_len = u8::to_be_bytes((LABEL_PREFIX.len() + label.len()) <span class="kw">as </span>u8); |
| <span class="kw">let </span>context_len = u8::to_be_bytes(context.len() <span class="kw">as </span>u8); |
| |
| <span class="kw">let </span>info = <span class="kw-2">&</span>[ |
| <span class="kw-2">&</span>output_len[..], |
| <span class="kw-2">&</span>label_len[..], |
| LABEL_PREFIX, |
| label, |
| <span class="kw-2">&</span>context_len[..], |
| context, |
| ]; |
| <span class="kw">let </span>okm = secret.expand(info, key_type).unwrap(); |
| |
| f(okm) |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>PayloadU8Len(<span class="kw">pub</span>(<span class="kw">crate</span>) usize); |
| <span class="kw">impl </span>hkdf::KeyType <span class="kw">for </span>PayloadU8Len { |
| <span class="kw">fn </span>len(<span class="kw-2">&</span><span class="self">self</span>) -> usize { |
| <span class="self">self</span>.<span class="number">0 |
| </span>} |
| } |
| |
| <span class="kw">impl </span>From<hkdf::Okm<<span class="lifetime">'_</span>, PayloadU8Len>> <span class="kw">for </span>PayloadU8 { |
| <span class="kw">fn </span>from(okm: hkdf::Okm<PayloadU8Len>) -> <span class="self">Self </span>{ |
| <span class="kw">let </span><span class="kw-2">mut </span>r = <span class="macro">vec!</span>[<span class="number">0u8</span>; okm.len().<span class="number">0</span>]; |
| okm.fill(<span class="kw-2">&mut </span>r[..]).unwrap(); |
| PayloadU8::new(r) |
| } |
| } |
| |
| <span class="kw">pub fn </span>derive_traffic_key( |
| secret: <span class="kw-2">&</span>hkdf::Prk, |
| aead_algorithm: <span class="kw-2">&</span><span class="lifetime">'static </span>aead::Algorithm, |
| ) -> aead::UnboundKey { |
| hkdf_expand(secret, aead_algorithm, <span class="string">b"key"</span>, <span class="kw-2">&</span>[]) |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>derive_traffic_iv(secret: <span class="kw-2">&</span>hkdf::Prk) -> Iv { |
| hkdf_expand(secret, IvLen, <span class="string">b"iv"</span>, <span class="kw-2">&</span>[]) |
| } |
| |
| <span class="attribute">#[cfg(test)] |
| </span><span class="kw">mod </span>test { |
| <span class="kw">use super</span>::{derive_traffic_iv, derive_traffic_key, KeySchedule, SecretKind}; |
| <span class="kw">use </span><span class="kw">crate</span>::KeyLog; |
| <span class="kw">use </span>ring::{aead, hkdf}; |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_vectors() { |
| <span class="comment">/* These test vectors generated with OpenSSL. */ |
| </span><span class="kw">let </span>hs_start_hash = [ |
| <span class="number">0xec</span>, <span class="number">0x14</span>, <span class="number">0x7a</span>, <span class="number">0x06</span>, <span class="number">0xde</span>, <span class="number">0xa3</span>, <span class="number">0xc8</span>, <span class="number">0x84</span>, <span class="number">0x6c</span>, <span class="number">0x02</span>, <span class="number">0xb2</span>, <span class="number">0x23</span>, <span class="number">0x8e</span>, <span class="number">0x41</span>, |
| <span class="number">0xbd</span>, <span class="number">0xdc</span>, <span class="number">0x9d</span>, <span class="number">0x89</span>, <span class="number">0xf9</span>, <span class="number">0xae</span>, <span class="number">0xa1</span>, <span class="number">0x7b</span>, <span class="number">0x5e</span>, <span class="number">0xfd</span>, <span class="number">0x4d</span>, <span class="number">0x74</span>, <span class="number">0x82</span>, <span class="number">0xaf</span>, |
| <span class="number">0x75</span>, <span class="number">0x88</span>, <span class="number">0x1c</span>, <span class="number">0x0a</span>, |
| ]; |
| |
| <span class="kw">let </span>hs_full_hash = [ |
| <span class="number">0x75</span>, <span class="number">0x1a</span>, <span class="number">0x3d</span>, <span class="number">0x4a</span>, <span class="number">0x14</span>, <span class="number">0xdf</span>, <span class="number">0xab</span>, <span class="number">0xeb</span>, <span class="number">0x68</span>, <span class="number">0xe9</span>, <span class="number">0x2c</span>, <span class="number">0xa5</span>, <span class="number">0x91</span>, <span class="number">0x8e</span>, |
| <span class="number">0x24</span>, <span class="number">0x08</span>, <span class="number">0xb9</span>, <span class="number">0xbc</span>, <span class="number">0xb0</span>, <span class="number">0x74</span>, <span class="number">0x89</span>, <span class="number">0x82</span>, <span class="number">0xec</span>, <span class="number">0x9c</span>, <span class="number">0x32</span>, <span class="number">0x30</span>, <span class="number">0xac</span>, <span class="number">0x30</span>, |
| <span class="number">0xbb</span>, <span class="number">0xeb</span>, <span class="number">0x23</span>, <span class="number">0xe2</span>, |
| ]; |
| |
| <span class="kw">let </span>ecdhe_secret = [ |
| <span class="number">0xe7</span>, <span class="number">0xb8</span>, <span class="number">0xfe</span>, <span class="number">0xf8</span>, <span class="number">0x90</span>, <span class="number">0x3b</span>, <span class="number">0x52</span>, <span class="number">0x0c</span>, <span class="number">0xb9</span>, <span class="number">0xa1</span>, <span class="number">0x89</span>, <span class="number">0x71</span>, <span class="number">0xb6</span>, <span class="number">0x9d</span>, |
| <span class="number">0xd4</span>, <span class="number">0x5d</span>, <span class="number">0xca</span>, <span class="number">0x53</span>, <span class="number">0xce</span>, <span class="number">0x2f</span>, <span class="number">0x12</span>, <span class="number">0xbf</span>, <span class="number">0x3b</span>, <span class="number">0xef</span>, <span class="number">0x93</span>, <span class="number">0x15</span>, <span class="number">0xe3</span>, <span class="number">0x12</span>, |
| <span class="number">0x71</span>, <span class="number">0xdf</span>, <span class="number">0x4b</span>, <span class="number">0x40</span>, |
| ]; |
| |
| <span class="kw">let </span>client_hts = [ |
| <span class="number">0x61</span>, <span class="number">0x7b</span>, <span class="number">0x35</span>, <span class="number">0x07</span>, <span class="number">0x6b</span>, <span class="number">0x9d</span>, <span class="number">0x0e</span>, <span class="number">0x08</span>, <span class="number">0xcf</span>, <span class="number">0x73</span>, <span class="number">0x1d</span>, <span class="number">0x94</span>, <span class="number">0xa8</span>, <span class="number">0x66</span>, |
| <span class="number">0x14</span>, <span class="number">0x78</span>, <span class="number">0x41</span>, <span class="number">0x09</span>, <span class="number">0xef</span>, <span class="number">0x25</span>, <span class="number">0x55</span>, <span class="number">0x51</span>, <span class="number">0x92</span>, <span class="number">0x1d</span>, <span class="number">0xd4</span>, <span class="number">0x6e</span>, <span class="number">0x04</span>, <span class="number">0x01</span>, |
| <span class="number">0x35</span>, <span class="number">0xcf</span>, <span class="number">0x46</span>, <span class="number">0xab</span>, |
| ]; |
| |
| <span class="kw">let </span>client_hts_key = [ |
| <span class="number">0x62</span>, <span class="number">0xd0</span>, <span class="number">0xdd</span>, <span class="number">0x00</span>, <span class="number">0xf6</span>, <span class="number">0x96</span>, <span class="number">0x19</span>, <span class="number">0xd3</span>, <span class="number">0xb8</span>, <span class="number">0x19</span>, <span class="number">0x3a</span>, <span class="number">0xb4</span>, <span class="number">0xa0</span>, <span class="number">0x95</span>, |
| <span class="number">0x85</span>, <span class="number">0xa7</span>, |
| ]; |
| |
| <span class="kw">let </span>client_hts_iv = [ |
| <span class="number">0xff</span>, <span class="number">0xf7</span>, <span class="number">0x5d</span>, <span class="number">0xf5</span>, <span class="number">0xad</span>, <span class="number">0x35</span>, <span class="number">0xd5</span>, <span class="number">0xcb</span>, <span class="number">0x3c</span>, <span class="number">0x53</span>, <span class="number">0xf3</span>, <span class="number">0xa9</span>, |
| ]; |
| |
| <span class="kw">let </span>server_hts = [ |
| <span class="number">0xfc</span>, <span class="number">0xf7</span>, <span class="number">0xdf</span>, <span class="number">0xe6</span>, <span class="number">0x4f</span>, <span class="number">0xa2</span>, <span class="number">0xc0</span>, <span class="number">0x4f</span>, <span class="number">0x62</span>, <span class="number">0x35</span>, <span class="number">0x38</span>, <span class="number">0x7f</span>, <span class="number">0x43</span>, <span class="number">0x4e</span>, |
| <span class="number">0x01</span>, <span class="number">0x42</span>, <span class="number">0x23</span>, <span class="number">0x36</span>, <span class="number">0xd9</span>, <span class="number">0xc0</span>, <span class="number">0x39</span>, <span class="number">0xde</span>, <span class="number">0x68</span>, <span class="number">0x47</span>, <span class="number">0xa0</span>, <span class="number">0xb9</span>, <span class="number">0xdd</span>, <span class="number">0xcf</span>, |
| <span class="number">0x29</span>, <span class="number">0xa8</span>, <span class="number">0x87</span>, <span class="number">0x59</span>, |
| ]; |
| |
| <span class="kw">let </span>server_hts_key = [ |
| <span class="number">0x04</span>, <span class="number">0x67</span>, <span class="number">0xf3</span>, <span class="number">0x16</span>, <span class="number">0xa8</span>, <span class="number">0x05</span>, <span class="number">0xb8</span>, <span class="number">0xc4</span>, <span class="number">0x97</span>, <span class="number">0xee</span>, <span class="number">0x67</span>, <span class="number">0x04</span>, <span class="number">0x7b</span>, <span class="number">0xbc</span>, |
| <span class="number">0xbc</span>, <span class="number">0x54</span>, |
| ]; |
| |
| <span class="kw">let </span>server_hts_iv = [ |
| <span class="number">0xde</span>, <span class="number">0x83</span>, <span class="number">0xa7</span>, <span class="number">0x3e</span>, <span class="number">0x9d</span>, <span class="number">0x81</span>, <span class="number">0x4b</span>, <span class="number">0x04</span>, <span class="number">0xc4</span>, <span class="number">0x8b</span>, <span class="number">0x78</span>, <span class="number">0x09</span>, |
| ]; |
| |
| <span class="kw">let </span>client_ats = [ |
| <span class="number">0xc1</span>, <span class="number">0x4a</span>, <span class="number">0x6d</span>, <span class="number">0x79</span>, <span class="number">0x76</span>, <span class="number">0xd8</span>, <span class="number">0x10</span>, <span class="number">0x2b</span>, <span class="number">0x5a</span>, <span class="number">0x0c</span>, <span class="number">0x99</span>, <span class="number">0x51</span>, <span class="number">0x49</span>, <span class="number">0x3f</span>, |
| <span class="number">0xee</span>, <span class="number">0x87</span>, <span class="number">0xdc</span>, <span class="number">0xaf</span>, <span class="number">0xf8</span>, <span class="number">0x2c</span>, <span class="number">0x24</span>, <span class="number">0xca</span>, <span class="number">0xb2</span>, <span class="number">0x14</span>, <span class="number">0xe8</span>, <span class="number">0xbe</span>, <span class="number">0x71</span>, <span class="number">0xa8</span>, |
| <span class="number">0x20</span>, <span class="number">0x6d</span>, <span class="number">0xbd</span>, <span class="number">0xa5</span>, |
| ]; |
| |
| <span class="kw">let </span>client_ats_key = [ |
| <span class="number">0xcc</span>, <span class="number">0x9f</span>, <span class="number">0x5f</span>, <span class="number">0x98</span>, <span class="number">0x0b</span>, <span class="number">0x5f</span>, <span class="number">0x10</span>, <span class="number">0x30</span>, <span class="number">0x6c</span>, <span class="number">0xba</span>, <span class="number">0xd7</span>, <span class="number">0xbe</span>, <span class="number">0x98</span>, <span class="number">0xd7</span>, |
| <span class="number">0x57</span>, <span class="number">0x2e</span>, |
| ]; |
| |
| <span class="kw">let </span>client_ats_iv = [ |
| <span class="number">0xb8</span>, <span class="number">0x09</span>, <span class="number">0x29</span>, <span class="number">0xe8</span>, <span class="number">0xd0</span>, <span class="number">0x2c</span>, <span class="number">0x70</span>, <span class="number">0xf6</span>, <span class="number">0x11</span>, <span class="number">0x62</span>, <span class="number">0xed</span>, <span class="number">0x6b</span>, |
| ]; |
| |
| <span class="kw">let </span>server_ats = [ |
| <span class="number">0x2c</span>, <span class="number">0x90</span>, <span class="number">0x77</span>, <span class="number">0x38</span>, <span class="number">0xd3</span>, <span class="number">0xf8</span>, <span class="number">0x37</span>, <span class="number">0x02</span>, <span class="number">0xd1</span>, <span class="number">0xe4</span>, <span class="number">0x59</span>, <span class="number">0x8f</span>, <span class="number">0x48</span>, <span class="number">0x48</span>, |
| <span class="number">0x53</span>, <span class="number">0x1d</span>, <span class="number">0x9f</span>, <span class="number">0x93</span>, <span class="number">0x65</span>, <span class="number">0x49</span>, <span class="number">0x1b</span>, <span class="number">0x9f</span>, <span class="number">0x7f</span>, <span class="number">0x52</span>, <span class="number">0xc8</span>, <span class="number">0x22</span>, <span class="number">0x29</span>, <span class="number">0x0d</span>, |
| <span class="number">0x4c</span>, <span class="number">0x23</span>, <span class="number">0x21</span>, <span class="number">0x92</span>, |
| ]; |
| |
| <span class="kw">let </span>server_ats_key = [ |
| <span class="number">0x0c</span>, <span class="number">0xb2</span>, <span class="number">0x95</span>, <span class="number">0x62</span>, <span class="number">0xd8</span>, <span class="number">0xd8</span>, <span class="number">0x8f</span>, <span class="number">0x48</span>, <span class="number">0xb0</span>, <span class="number">0x2c</span>, <span class="number">0xbf</span>, <span class="number">0xbe</span>, <span class="number">0xd7</span>, <span class="number">0xe6</span>, |
| <span class="number">0x2b</span>, <span class="number">0xb3</span>, |
| ]; |
| |
| <span class="kw">let </span>server_ats_iv = [ |
| <span class="number">0x0d</span>, <span class="number">0xb2</span>, <span class="number">0x8f</span>, <span class="number">0x98</span>, <span class="number">0x85</span>, <span class="number">0x86</span>, <span class="number">0xa1</span>, <span class="number">0xb7</span>, <span class="number">0xe4</span>, <span class="number">0xd5</span>, <span class="number">0xc6</span>, <span class="number">0x9c</span>, |
| ]; |
| |
| <span class="kw">let </span>hkdf = hkdf::HKDF_SHA256; |
| <span class="kw">let </span><span class="kw-2">mut </span>ks = KeySchedule::new_with_empty_secret(hkdf); |
| ks.input_secret(<span class="kw-2">&</span>ecdhe_secret); |
| |
| assert_traffic_secret( |
| <span class="kw-2">&</span>ks, |
| SecretKind::ClientHandshakeTrafficSecret, |
| <span class="kw-2">&</span>hs_start_hash, |
| <span class="kw-2">&</span>client_hts, |
| <span class="kw-2">&</span>client_hts_key, |
| <span class="kw-2">&</span>client_hts_iv, |
| ); |
| |
| assert_traffic_secret( |
| <span class="kw-2">&</span>ks, |
| SecretKind::ServerHandshakeTrafficSecret, |
| <span class="kw-2">&</span>hs_start_hash, |
| <span class="kw-2">&</span>server_hts, |
| <span class="kw-2">&</span>server_hts_key, |
| <span class="kw-2">&</span>server_hts_iv, |
| ); |
| |
| ks.input_empty(); |
| |
| assert_traffic_secret( |
| <span class="kw-2">&</span>ks, |
| SecretKind::ClientApplicationTrafficSecret, |
| <span class="kw-2">&</span>hs_full_hash, |
| <span class="kw-2">&</span>client_ats, |
| <span class="kw-2">&</span>client_ats_key, |
| <span class="kw-2">&</span>client_ats_iv, |
| ); |
| |
| assert_traffic_secret( |
| <span class="kw-2">&</span>ks, |
| SecretKind::ServerApplicationTrafficSecret, |
| <span class="kw-2">&</span>hs_full_hash, |
| <span class="kw-2">&</span>server_ats, |
| <span class="kw-2">&</span>server_ats_key, |
| <span class="kw-2">&</span>server_ats_iv, |
| ); |
| } |
| |
| <span class="kw">fn </span>assert_traffic_secret( |
| ks: <span class="kw-2">&</span>KeySchedule, |
| kind: SecretKind, |
| hash: <span class="kw-2">&</span>[u8], |
| expected_traffic_secret: <span class="kw-2">&</span>[u8], |
| expected_key: <span class="kw-2">&</span>[u8], |
| expected_iv: <span class="kw-2">&</span>[u8], |
| ) { |
| <span class="kw">struct </span>Log<<span class="lifetime">'a</span>>(<span class="kw-2">&</span><span class="lifetime">'a </span>[u8]); |
| <span class="kw">impl </span>KeyLog <span class="kw">for </span>Log<<span class="lifetime">'_</span>> { |
| <span class="kw">fn </span>log(<span class="kw-2">&</span><span class="self">self</span>, _label: <span class="kw-2">&</span>str, _client_random: <span class="kw-2">&</span>[u8], secret: <span class="kw-2">&</span>[u8]) { |
| <span class="macro">assert_eq!</span>(<span class="self">self</span>.<span class="number">0</span>, secret); |
| } |
| } |
| <span class="kw">let </span>log = Log(expected_traffic_secret); |
| <span class="kw">let </span>traffic_secret = ks.derive_logged_secret(kind, <span class="kw-2">&</span>hash, <span class="kw-2">&</span>log, <span class="kw-2">&</span>[<span class="number">0</span>; <span class="number">32</span>]); |
| |
| <span class="comment">// Since we can't test key equality, we test the output of sealing with the key instead. |
| </span><span class="kw">let </span>aead_alg = <span class="kw-2">&</span>aead::AES_128_GCM; |
| <span class="kw">let </span>key = derive_traffic_key(<span class="kw-2">&</span>traffic_secret, aead_alg); |
| <span class="kw">let </span>seal_output = seal_zeroes(key); |
| <span class="kw">let </span>expected_key = aead::UnboundKey::new(aead_alg, expected_key).unwrap(); |
| <span class="kw">let </span>expected_seal_output = seal_zeroes(expected_key); |
| <span class="macro">assert_eq!</span>(seal_output, expected_seal_output); |
| <span class="macro">assert!</span>(seal_output.len() >= <span class="number">48</span>); <span class="comment">// Sanity check. |
| |
| </span><span class="kw">let </span>iv = derive_traffic_iv(<span class="kw-2">&</span>traffic_secret); |
| <span class="macro">assert_eq!</span>(iv.value(), expected_iv); |
| } |
| |
| <span class="kw">fn </span>seal_zeroes(key: aead::UnboundKey) -> Vec<u8> { |
| <span class="kw">let </span>key = aead::LessSafeKey::new(key); |
| <span class="kw">let </span><span class="kw-2">mut </span>seal_output = <span class="macro">vec!</span>[<span class="number">0</span>; <span class="number">32</span>]; |
| key.seal_in_place_append_tag( |
| aead::Nonce::assume_unique_for_key([<span class="number">0</span>; aead::NONCE_LEN]), |
| aead::Aad::empty(), |
| <span class="kw-2">&mut </span>seal_output, |
| ) |
| .unwrap(); |
| seal_output |
| } |
| } |
| </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> |
