{"id":981,"date":"2014-04-21T15:10:48","date_gmt":"2014-04-21T15:10:48","guid":{"rendered":"https:\/\/trouble.org\/?p=981"},"modified":"2014-04-21T15:10:48","modified_gmt":"2014-04-21T15:10:48","slug":"random-bits","status":"publish","type":"post","link":"https:\/\/trouble.org\/?p=981","title":{"rendered":"Random bits"},"content":{"rendered":"<p>&#8230; well, literally&#8230; or pseudo literally?<\/p>\n<p>To generate 128 bits of pseudo-randomness:<\/p>\n<div class=\"codecolorer-container bash blackboard\" style=\"overflow:auto;white-space:nowrap;\"><div class=\"bash codecolorer\"><span class=\"kw2\">dd<\/span> <span class=\"re2\">if<\/span>=<span class=\"sy0\">\/<\/span>dev<span class=\"sy0\">\/<\/span>urandom <span class=\"re2\">bs<\/span>=<span class=\"nu0\">16<\/span> <span class=\"re2\">count<\/span>=<span class=\"nu0\">1<\/span> <span class=\"nu0\">2<\/span><span class=\"sy0\">&gt;\/<\/span>dev<span class=\"sy0\">\/<\/span>null<span class=\"sy0\">|<\/span> <span class=\"kw2\">hexdump<\/span> <span class=\"sy0\">|<\/span><span class=\"kw2\">awk<\/span> <span class=\"st_h\">'{$1=&quot;&quot;; printf(&quot;%s&quot;, $0)}'<\/span> <span class=\"sy0\">|<\/span> <span class=\"kw2\">sed<\/span> <span class=\"st_h\">'s\/ \/\/g'<\/span><\/div><\/div>\n<p>Block size 16 = 16 bytes&#8230; do that once (count=1); that&#8217;s 16 bytes * 8 bits\/byte = 128 bits.  I&#8217;ve been using this in scripts lately, like &#8220;foo=$(&#8230;)&#8221;.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>&#8230; well, literally&#8230; or pseudo literally? To generate 128 bits of pseudo-randomness: dd if=\/dev\/urandom bs=16 count=1 2&gt;\/dev\/null| hexdump |awk &#8216;{$1=&quot;&quot;; printf(&quot;%s&quot;, $0)}&#8217; | sed &#8216;s\/ \/\/g&#8217; Block size 16 = 16 bytes&#8230; do that once (count=1); that&#8217;s 16 bytes * 8 bits\/byte = 128 bits. I&#8217;ve been using this in scripts lately, like &#8220;foo=$(&#8230;)&#8221;.<\/p>\n","protected":false},"author":44,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[260,88,4,6],"tags":[342,268,267,269],"class_list":["post-981","post","type-post","status-publish","format-standard","hentry","category-crypto","category-dinosaurs","category-security","category-tech","tag-crypto","tag-misc","tag-random","tag-trivia"],"_links":{"self":[{"href":"https:\/\/trouble.org\/index.php?rest_route=\/wp\/v2\/posts\/981","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/trouble.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/trouble.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/trouble.org\/index.php?rest_route=\/wp\/v2\/users\/44"}],"replies":[{"embeddable":true,"href":"https:\/\/trouble.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=981"}],"version-history":[{"count":1,"href":"https:\/\/trouble.org\/index.php?rest_route=\/wp\/v2\/posts\/981\/revisions"}],"predecessor-version":[{"id":982,"href":"https:\/\/trouble.org\/index.php?rest_route=\/wp\/v2\/posts\/981\/revisions\/982"}],"wp:attachment":[{"href":"https:\/\/trouble.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=981"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/trouble.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=981"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/trouble.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=981"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}