123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285
  1. <?xml version="1.0" encoding="utf-8"?>
  2. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
  3. "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
  4. <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
  5. <head>
  6. <title></title>
  7. <!-- 2018-04-12 Thu 12:20 -->
  8. <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
  9. <meta name="generator" content="Org-mode" />
  10. <meta name="author" content="Bob Mottram" />
  11. <meta name="description" content="How to use KEYSERVER"
  12. />
  13. <meta name="keywords" content="freedombone, keyserver" />
  14. <style type="text/css">
  15. <!--/*--><![CDATA[/*><!--*/
  16. .title { text-align: center; }
  17. .todo { font-family: monospace; color: red; }
  18. .done { color: green; }
  19. .tag { background-color: #eee; font-family: monospace;
  20. padding: 2px; font-size: 80%; font-weight: normal; }
  21. .timestamp { color: #bebebe; }
  22. .timestamp-kwd { color: #5f9ea0; }
  23. .right { margin-left: auto; margin-right: 0px; text-align: right; }
  24. .left { margin-left: 0px; margin-right: auto; text-align: left; }
  25. .center { margin-left: auto; margin-right: auto; text-align: center; }
  26. .underline { text-decoration: underline; }
  27. #postamble p, #preamble p { font-size: 90%; margin: .2em; }
  28. p.verse { margin-left: 3%; }
  29. pre {
  30. border: 1px solid #ccc;
  31. box-shadow: 3px 3px 3px #eee;
  32. padding: 8pt;
  33. font-family: monospace;
  34. overflow: auto;
  35. margin: 1.2em;
  36. }
  37. pre.src {
  38. position: relative;
  39. overflow: visible;
  40. padding-top: 1.2em;
  41. }
  42. pre.src:before {
  43. display: none;
  44. position: absolute;
  45. background-color: white;
  46. top: -10px;
  47. right: 10px;
  48. padding: 3px;
  49. border: 1px solid black;
  50. }
  51. pre.src:hover:before { display: inline;}
  52. pre.src-sh:before { content: 'sh'; }
  53. pre.src-bash:before { content: 'sh'; }
  54. pre.src-emacs-lisp:before { content: 'Emacs Lisp'; }
  55. pre.src-R:before { content: 'R'; }
  56. pre.src-perl:before { content: 'Perl'; }
  57. pre.src-java:before { content: 'Java'; }
  58. pre.src-sql:before { content: 'SQL'; }
  59. table { border-collapse:collapse; }
  60. caption.t-above { caption-side: top; }
  61. caption.t-bottom { caption-side: bottom; }
  62. td, th { vertical-align:top; }
  63. th.right { text-align: center; }
  64. th.left { text-align: center; }
  65. th.center { text-align: center; }
  66. td.right { text-align: right; }
  67. td.left { text-align: left; }
  68. td.center { text-align: center; }
  69. dt { font-weight: bold; }
  70. .footpara:nth-child(2) { display: inline; }
  71. .footpara { display: block; }
  72. .footdef { margin-bottom: 1em; }
  73. .figure { padding: 1em; }
  74. .figure p { text-align: center; }
  75. .inlinetask {
  76. padding: 10px;
  77. border: 2px solid gray;
  78. margin: 10px;
  79. background: #ffffcc;
  80. }
  81. #org-div-home-and-up
  82. { text-align: right; font-size: 70%; white-space: nowrap; }
  83. textarea { overflow-x: auto; }
  84. .linenr { font-size: smaller }
  85. .code-highlighted { background-color: #ffff00; }
  86. .org-info-js_info-navigation { border-style: none; }
  87. #org-info-js_console-label
  88. { font-size: 10px; font-weight: bold; white-space: nowrap; }
  89. .org-info-js_search-highlight
  90. { background-color: #ffff00; color: #000000; font-weight: bold; }
  91. /*]]>*/-->
  92. </style>
  93. <link rel="stylesheet" type="text/css" href="freedombone.css" />
  94. <script type="text/javascript">
  95. /*
  96. @licstart The following is the entire license notice for the
  97. JavaScript code in this tag.
  98. Copyright (C) 2012-2013 Free Software Foundation, Inc.
  99. The JavaScript code in this tag is free software: you can
  100. redistribute it and/or modify it under the terms of the GNU
  101. General Public License (GNU GPL) as published by the Free Software
  102. Foundation, either version 3 of the License, or (at your option)
  103. any later version. The code is distributed WITHOUT ANY WARRANTY;
  104. without even the implied warranty of MERCHANTABILITY or FITNESS
  105. FOR A PARTICULAR PURPOSE. See the GNU GPL for more details.
  106. As additional permission under GNU GPL version 3 section 7, you
  107. may distribute non-source (e.g., minimized or compacted) forms of
  108. that code without the copy of the GNU GPL normally required by
  109. section 4, provided you include this license notice and a URL
  110. through which recipients can access the Corresponding Source.
  111. @licend The above is the entire license notice
  112. for the JavaScript code in this tag.
  113. */
  114. <!--/*--><![CDATA[/*><!--*/
  115. function CodeHighlightOn(elem, id)
  116. {
  117. var target = document.getElementById(id);
  118. if(null != target) {
  119. elem.cacheClassElem = elem.className;
  120. elem.cacheClassTarget = target.className;
  121. target.className = "code-highlighted";
  122. elem.className = "code-highlighted";
  123. }
  124. }
  125. function CodeHighlightOff(elem, id)
  126. {
  127. var target = document.getElementById(id);
  128. if(elem.cacheClassElem)
  129. elem.className = elem.cacheClassElem;
  130. if(elem.cacheClassTarget)
  131. target.className = elem.cacheClassTarget;
  132. }
  133. /*]]>*///-->
  134. </script>
  135. </head>
  136. <body>
  137. <div id="preamble" class="status">
  138. <a name="top" id="top"></a>
  139. </div>
  140. <div id="content">
  141. <h1 class="title"></h1>
  142. <div class="figure">
  143. <p><img src="images/logo.png" alt="logo.png" width="80%" height="10%" align="center" />
  144. </p>
  145. </div>
  146. <div id="outline-container-sec-1" class="outline-2">
  147. <h2 id="sec-1">OpenPGP Key Server</h2>
  148. <div class="outline-text-2" id="text-1">
  149. <p>
  150. The <i>web of trust</i> is a nice idea, but how trustable is it? If you take a look at how many OpenPGP key servers are out there then there are a two or three main ones and not much else. Can you trust those servers? Who is maintaining them and how often? Is any censorship going on? How hard would it be for adversaries to get implants onto them? In terms of technology this infrastructure is quite old and it could have been neglected for a long time. Once vigilant maintainers might have turned lazy and gotten lax with server security, or been recruited over to the dark side.
  151. </p>
  152. <p>
  153. For these kinds of reasons you might prefer to run your own web of trust infrastructure. In simple terms it's a database of GPG public keys which provides a way for users to <i>find out how to communicate with others securely via email</i>. You can meet in person and exchange public keys via sneakernet on USB drives, but most users of GPG don't do that. Instead they just download the public key for a given email address from one of the key servers.
  154. </p>
  155. <div class="figure">
  156. <p><img src="images/keyserver.jpg" alt="keyserver.jpg" width="80%" align="center" />
  157. </p>
  158. </div>
  159. </div>
  160. </div>
  161. <div id="outline-container-sec-2" class="outline-2">
  162. <h2 id="sec-2">Installation</h2>
  163. <div class="outline-text-2" id="text-2">
  164. <p>
  165. ssh into the system with:
  166. </p>
  167. <div class="org-src-container">
  168. <pre class="src src-bash">ssh myusername@mydomain.com -p 2222
  169. </pre>
  170. </div>
  171. <p>
  172. Select <b>Add/Remove Apps</b> then <b>keyserver</b>. You will then be asked for a domain name and if you are using FreeDNS also the code for the domain which can be found under <b>Dynamic DNS</b> on the FreeDNS site (the random string from "<i>quick cron example</i>" which appears after <i>update.php?</i> and before <i>&gt;&gt;</i>). For more details on obtaining a domain and making it accessible via dynamic DNS see the <a href="./faq.html">FAQ</a>. Typically the domain name you use will be a subdomain, such as <i>keys.mydomainname.net</i>. It will need to be a domain which you have bought somewhere and own and not one of the FreeDNS subdomains, otherwise you won't be able to get a SSL/TLS certificate for it.
  173. </p>
  174. <p>
  175. After the install has completed go to <b>Security settings</b> and select <b>Create a new Let's Encrypt certificate</b> and enter the domain name that you are using for the Key server. If the certificate is obtained successfully then you will see a congratulations message.
  176. </p>
  177. </div>
  178. </div>
  179. <div id="outline-container-sec-3" class="outline-2">
  180. <h2 id="sec-3">How to use it</h2>
  181. <div class="outline-text-2" id="text-3">
  182. <p>
  183. Interaction with the web user interface is pretty minimal and obvious, but most likely you will also want to be able to use your keyserver from the commandline. To do that use the <b>&#x2013;keyserver</b> option. For example to search for a key on your server:
  184. </p>
  185. <div class="org-src-container">
  186. <pre class="src src-bash">gpg --keyserver [your keyserver domain] --search-keys [email address]
  187. </pre>
  188. </div>
  189. <p>
  190. Or to send a key to it:
  191. </p>
  192. <div class="org-src-container">
  193. <pre class="src src-bash">gpg --keyserver [your keyserver domain] --send-keys [email address or key ID]
  194. </pre>
  195. </div>
  196. <p>
  197. Or to get a key:
  198. </p>
  199. <div class="org-src-container">
  200. <pre class="src src-bash">gpg --keyserver [your keyserver domain] --recv-keys [email address or key ID]
  201. </pre>
  202. </div>
  203. </div>
  204. </div>
  205. <div id="outline-container-sec-4" class="outline-2">
  206. <h2 id="sec-4">Sync with other keyservers</h2>
  207. <div class="outline-text-2" id="text-4">
  208. <p>
  209. Key servers avoid censorship or errors by gossiping between each other and cross referencing the data. You can define which other servers your key server will gossip with by going to the <b>Administrator control panel</b>, selecting <b>App Settings</b> then <b>keyserver</b> then <b>Sync with other keyserver</b>.
  210. </p>
  211. <p>
  212. It's a good idea not to try to sync with the popular OpenPGP key servers, because those have gigantic databases which may make your server unstable and certainly would make it hard to create backups within a tractable amount of time. This option is mainly intended to sync with other Freedombone systems or small home servers within a particular community.
  213. </p>
  214. </div>
  215. </div>
  216. <div id="outline-container-sec-5" class="outline-2">
  217. <h2 id="sec-5">Possible problems</h2>
  218. <div class="outline-text-2" id="text-5">
  219. <p>
  220. OpenPGP key servers are not very well defended from flooding attacks. This means that an adversary could just upload a billion keys to destabilize the server and fill it with nonsense to make it unusable. Since key servers are <i>fully open to the public</i> there isn't anything to prevent that from happening.
  221. </p>
  222. <p>
  223. Within the Freedombone system there is a watchdog script which keeps track of the key server database size, and disables the key server if that gets too large. Apart from the usual firewall and web server traffic rate limits, this is a crude but probably practical way of defending against flooding.
  224. </p>
  225. <p>
  226. If a flood attack does happen then really the only way to recover is to restore from the last known good backup, which can be done from the <b>Administrator control panel</b>.
  227. </p>
  228. </div>
  229. </div>
  230. </div>
  231. <div id="postamble" class="status">
  232. <style type="text/css">
  233. .back-to-top {
  234. position: fixed;
  235. bottom: 2em;
  236. right: 0px;
  237. text-decoration: none;
  238. color: #000000;
  239. background-color: rgba(235, 235, 235, 0.80);
  240. font-size: 12px;
  241. padding: 1em;
  242. display: none;
  243. }
  244. .back-to-top:hover {
  245. background-color: rgba(135, 135, 135, 0.50);
  246. }
  247. </style>
  248. <div class="back-to-top">
  249. <a href="#top">Back to top</a> | <a href="mailto:bob@freedombone.net">E-mail me</a>
  250. </div>
  251. </div>
  252. </body>
  253. </html>