{"id":31080,"date":"2019-10-31T21:39:19","date_gmt":"2019-10-31T18:39:19","guid":{"rendered":"https:\/\/prohoster.info\/blog\/steganografiya-v-fajlovoj-sisteme\/"},"modified":"2019-10-31T21:39:19","modified_gmt":"2019-10-31T18:39:19","slug":"steganografiya-v-fajlovoj-sisteme","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/steganografiya-v-fajlovoj-sisteme","title":{"rendered":"Steganografie v souborov\u00e9m syst\u00e9mu","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"<p>Ahoj, Habr. <\/p>\n<p><\/p>\n<p>Chci v\u00e1m p\u0159edstavit mal\u00fd projekt na <noindex><a rel=\"nofollow\" href=\"https:\/\/ru.wikipedia.org\/wiki\/%D0%A1%D1%82%D0%B5%D0%B3%D0%B0%D0%BD%D0%BE%D0%B3%D1%80%D0%B0%D1%84%D0%B8%D1%8F\">steganografii<\/a><\/noindex>, kter\u00fd byl vytvo\u0159en ve voln\u00e9m \u010dase od studia. <\/p>\n<p><\/p>\n<p>Vytvo\u0159il jsem projekt pro skryt\u00e9 ukl\u00e1d\u00e1n\u00ed informac\u00ed do souborov\u00e9ho syst\u00e9mu (d\u00e1le jen <strong>FS<\/strong>).<br \/>\nTo lze pou\u017e\u00edt k kr\u00e1de\u017ei d\u016fv\u011brn\u00fdch informac\u00ed pro vzd\u011bl\u00e1vac\u00ed \u00fa\u010dely.<\/p>\n<p><\/p>\n<p><img decoding=\"async\" alt=\"Steganografie v souborov\u00e9m syst\u00e9mu\" src=\"\/wp-content\/uploads\/2019\/04\/d6639b37e1b1fe57b80288e671176fe3.jpg\" style=\"display:block;margin: 0 auto;\" \/><\/p>\n<p><\/p>\n<p>Jako experiment\u00e1ln\u00ed vzorek byla zvolena ji\u017e pom\u011brn\u011b star\u00e1 linuxov\u00e1 FS <noindex><a rel=\"nofollow\" href=\"https:\/\/ru.wikipedia.org\/wiki\/Ext2\">ext2<\/a><\/noindex>. <\/p>\n<p>\n<noindex><a rel=\"nofollow\" name=\"habracut\"><\/a><\/noindex><\/p>\n<h3 id=\"realizaciya\">Implementace<\/h3>\n<p><\/p>\n<h4 id=\"soobrazheniya-o-realizacii\">\u00davahy o realizaci<\/h4>\n<p><\/p>\n<p>Pokud d\u016fkladn\u011b \u201erozm\u011bl\u0148ujete\u201c standard ext2, lze nahradit, \u017ee ve FS existuje takzvan\u00fd <noindex><a rel=\"nofollow\" href=\"http:\/\/www.nongnu.org\/ext2-doc\/ext2.html#SUPERBLOCK\"><strong>Superbloks<\/strong><\/a><\/noindex>, ve kter\u00e9m jsou uvedeny z\u00e1kladn\u00ed informace o syst\u00e9mu. Po m\u011b bylo nalezeno <noindex><a rel=\"nofollow\" href=\"http:\/\/www.nongnu.org\/ext2-doc\/ext2.html#BLOCK-BITMAP\"><strong>Bitmapa bloku<\/strong><\/a><\/noindex> a <noindex><a rel=\"nofollow\" href=\"http:\/\/www.nongnu.org\/ext2-doc\/ext2.html#INODE-TABLE\"><strong>Inode tabulka<\/strong><\/a><\/noindex>. T\u00e9m\u011b\u0159 okam\u017eit\u011b vznikl n\u00e1pad zapisovat informace do pr\u00e1zdn\u00fdch v tuto chv\u00edli blok\u016f FS. Nyn\u00ed bylo t\u0159eba promyslet ochranu proti program\u00e1torovi ozbrojen\u00e9mu <noindex><a rel=\"nofollow\" href=\"https:\/\/ru.wikipedia.org\/wiki\/Hex-%D1%80%D0%B5%D0%B4%D0%B0%D0%BA%D1%82%D0%BE%D1%80\">hex-editoru<\/a><\/noindex>. <\/p>\n<p><\/p>\n<p>Pokud se skryt\u00e1 informace ukl\u00e1d\u00e1 bez \u0161ifrov\u00e1n\u00ed, i kdy\u017e je rozpt\u00fdlen\u00e1 po FS, st\u00e1le bude p\u0159\u00edli\u0161 n\u00e1padn\u00e1, zejm\u00e9na pokud program\u00e1tor v\u00ed, co hledat. Proto bylo rozhodnuto \u0161ifrovat v\u0161echny bloky p\u016fvodn\u00edho souboru. Vybral jsem blokov\u00e9 \u0161ifrov\u00e1n\u00ed <noindex><a rel=\"nofollow\" href=\"https:\/\/ru.wikipedia.org\/wiki\/Advanced_Encryption_Standard\">AES<\/a><\/noindex>, ale jak ch\u00e1pete, to nen\u00ed z\u00e1sadn\u00ed.<\/p>\n<p><\/p>\n<p>Abychom odd\u011blili pot\u0159ebn\u00e9 bloky od v\u0161ech ostatn\u00edch p\u0159i \u010dten\u00ed, rozhodli jsme se p\u0159idat speci\u00e1ln\u00ed marker na za\u010d\u00e1tek ka\u017ed\u00e9ho bloku. Tento marker byl \u0161ifrov\u00e1n v z\u00e1vislosti na \u010d\u00edsle bloku v p\u016fvodn\u00edm souboru. Tato lest nejen umo\u017enila naj\u00edt pot\u0159ebn\u00e9 bloky, ale tak\u00e9 zjistit jejich spr\u00e1vn\u00e9 po\u0159ad\u00ed.<\/p>\n<p><\/p>\n<p>Obecn\u00fd princip fungov\u00e1n\u00ed syst\u00e9mu.<\/p>\n<p><\/p>\n<p><img decoding=\"async\" alt=\"Steganografie v souborov\u00e9m syst\u00e9mu\" src=\"\/wp-content\/uploads\/2019\/04\/cb6e712aeffafe87b1ad10e4ed5b0a39.jpg\" style=\"display:block;margin: 0 auto;\" \/><\/p>\n<p><\/p>\n<h4 id=\"algoritm-zapisi\">Algoritmus z\u00e1pisu<\/h4>\n<p><\/p>\n<p>Po jednotliv\u00fdch bodech:<\/p>\n<p><\/p>\n<ul>\n<li>Nejprve zapsat do p\u016fvodn\u00edho souborov\u00e9ho syst\u00e9mu n\u011bjak\u00e9 informace;<\/li>\n<li>Smazat tyto informace (ne nutn\u011b v\u0161echny); <\/li>\n<li>Soubor pro skryt\u00ed rozd\u011blit na bloky stejn\u00e9 d\u00e9lky a p\u0159idat marker;<\/li>\n<li>\u0160ifrovat tyto bloky;<\/li>\n<li>Um\u00edstit za\u0161ifrovan\u00e9 bloky do pr\u00e1zdn\u00fdch blok\u016f FS.<\/li>\n<\/ul>\n<p>\n<b class=\"spoiler_title\">Pro milovn\u00edky blokov\u00fdch sch\u00e9mat<\/b><\/p>\n<p>N\u00ed\u017ee je uvedeno blokov\u00e9 sch\u00e9ma algoritmu z\u00e1pisu. Na vstupu algoritmus p\u0159ij\u00edm\u00e1 \u010dty\u0159i soubory:<br \/>\n-Obr\u00e1zek m\u011bniteln\u00fd souborov\u00fd syst\u00e9m;<br \/>\n-Soubor ur\u010den\u00fd pro steganografii;<br \/>\n-Soubor s \u0161ifrovac\u00edm kl\u00ed\u010dem pro AES;<br \/>\n-Soubor s markerem.<br \/>\n<img decoding=\"async\" alt=\"Steganografie v souborov\u00e9m syst\u00e9mu\" src=\"\/wp-content\/uploads\/2019\/04\/3089bf0d55cbdca1a98e4ee992089665.jpg\" style=\"display:block;margin: 0 auto;\" \/><\/p>\n<p><\/p>\n<p>Hned je t\u0159eba poznamenat, \u017ee tento algoritmus m\u00e1 jednu nev\u00fdhodu: po zaps\u00e1n\u00ed souboru do FS, <strong>zad\u00e1vat URL (to nikdy nefungovalo, ale vstupn\u00ed pole umo\u017e\u0148ovalo uv\u00e9st URL, co\u017e zm\u00e1tlo u\u017eivatele).<\/strong> zapisovat do FS n\u011bco nov\u00e9ho, proto\u017ee jak\u00e1koli nov\u00e1 informace m\u016f\u017ee skon\u010dit v t\u011bch bloc\u00edch, kter\u00e9 jsme vyhradili na\u0161emu steganografovan\u00e9mu souboru, ale to z\u00e1rove\u0148 otev\u00edr\u00e1 mo\u017enost \u201erychl\u00e9ho zamet\u00e1n\u00ed stop\u201c. <\/p>\n<p><\/p>\n<p>Je v\u0161ak z\u0159ejm\u00e9, jak to lze opravit: je t\u0159eba p\u0159epsat algoritmus z\u00e1pisu blok\u016f do FS. Je to pochopiteln\u00fd, ale nesm\u00edrn\u011b pracn\u00fd \u00fakol.<br \/>\nPro Proof Of Concept jsem to neimplementoval.<\/p>\n<p><\/p>\n<p>V d\u016fsledku toho budou n\u00e1sleduj\u00edc\u00ed zm\u011bny ve FS, takto vypad\u00e1 FS p\u0159ed steganografi\u00ed (p\u0159edem byl zaznamen\u00e1n audiov\u00fd soubor).<br \/>\n<img decoding=\"async\" alt=\"Steganografie v souborov\u00e9m syst\u00e9mu\" src=\"\/wp-content\/uploads\/2019\/04\/a779de50121de2bafacab9d891b5f5df.jpg\" style=\"display:block;margin: 0 auto;\" \/><br \/>\nA takto vypad\u00e1 FS s ji\u017e zakrytou informac\u00ed.<br \/>\n<img decoding=\"async\" alt=\"Steganografie v souborov\u00e9m syst\u00e9mu\" src=\"\/wp-content\/uploads\/2019\/04\/5722200a90d720f96c0aad5b4a5a11ae.jpg\" style=\"display:block;margin: 0 auto;\" \/><\/p>\n<p><\/p>\n<h4 id=\"algoritm-chteniya\">Algoritmus \u010dten\u00ed<\/h4>\n<p><\/p>\n<p>Po jednotliv\u00fdch bodech:<\/p>\n<p><\/p>\n<ul>\n<li>Se znalost\u00ed kl\u00ed\u010de a zp\u016fsobu vytv\u00e1\u0159en\u00ed marker\u016f sestavit prvn\u00edch N marker\u016f, s garanc\u00ed, \u017ee N, n\u00e1soben\u00e9 d\u00e9lkou bloku souborov\u00e9ho syst\u00e9mu, je v\u011bt\u0161\u00ed ne\u017e d\u00e9lka zakryt\u00e9 souboru;<\/li>\n<li>Prove\u010fte vyhled\u00e1v\u00e1n\u00ed blok\u016f ve FS, za\u010d\u00ednaj\u00edc\u00edch s markery; <\/li>\n<li>De\u0161ifrovat z\u00edskan\u00e9 bloky a odd\u011blit markery;<\/li>\n<li>Sestavit z\u00edskan\u00e9 bloky ve spr\u00e1vn\u00e9m po\u0159ad\u00ed a z\u00edskat p\u016fvodn\u00ed soubor.<\/li>\n<\/ul>\n<p>\n<b class=\"spoiler_title\">Pro milovn\u00edky blokov\u00fdch sch\u00e9mat<\/b><\/p>\n<p>N\u00ed\u017ee je zn\u00e1zorn\u011bn blokov\u00fd diagram algoritmu z\u00e1pisu. Na vstupu algoritmu jsou t\u0159i soubory:<br \/>\n- Obraz souborov\u00e9ho syst\u00e9mu;<br \/>\n-Soubor s \u0161ifrovac\u00edm kl\u00ed\u010dem pro AES;<br \/>\n-Soubor s markerem.<br \/>\n<img decoding=\"async\" alt=\"Steganografie v souborov\u00e9m syst\u00e9mu\" src=\"\/wp-content\/uploads\/2019\/04\/9dcfe680121a30c1b17b5a4cdbd76dc3.jpg\" style=\"display:block;margin: 0 auto;\" \/><\/p>\n<p><\/p>\n<p>Po spu\u0161t\u011bn\u00ed programu se objev\u00ed soubor Read, kter\u00fd bude extrahovan\u00fd ze steganografick\u00e9ho FS souboru. Pokud byly kl\u00ed\u010d nebo marker uvedeny nespr\u00e1vn\u011b, soubor Read bude pr\u00e1zdn\u00fd.<br \/>\n(pro milovn\u00edky kr\u00e1sy lze zahrnout nejen soubor, ale tak\u00e9 \u201ehlavi\u010dku\u201c, obsahuj\u00edc\u00ed meta informace: jm\u00e9no souboru, opr\u00e1vn\u011bn\u00ed, \u010das posledn\u00ed zm\u011bny atd.)<\/p>\n<p><\/p>\n<h4 id=\"avtomatizaciya-zapuska\">Automatizace spu\u0161t\u011bn\u00ed<\/h4>\n<p><\/p>\n<p>Pro pohodl\u00ed byly naps\u00e1ny bash skripty, kter\u00e9 automatizuj\u00ed spu\u0161t\u011bn\u00ed na Linuxu (testov\u00e1no na Ubuntu 16.04.3 LTS).<br \/>\nProbereme spu\u0161t\u011bn\u00ed krok za krokem.<br \/>\nZ\u00e1pis:<\/p>\n<p><\/p>\n<ol>\n<li>sudo Copy_Flash.sh \u201cDEVICE\u201d \u2014 z\u00edsk\u00e1me obraz FS z DEVICE (flashe);<\/li>\n<li>.\\\/Write.sh \u201cFILE\u201d \u201cKEY\u201d \u201cMARKER\u201d \u2013 vytvo\u0159\u00edme virtu\u00e1ln\u00ed prost\u0159ed\u00ed, st\u00e1hneme pot\u0159ebn\u00e9 knihovny a spust\u00edme skript na z\u00e1pis;<\/li>\n<li>sudo .\\\/Write_Flash.sh \u201cDEVICE\u201d \u2013 zaps\u00e1n\u00ed upraven\u00e9ho FS op\u011bt na DEVICE.<\/li>\n<\/ol>\n<p><\/p>\n<p>\u010cten\u00ed:<\/p>\n<p><\/p>\n<ol>\n<li>sudo Copy_Flash.sh \u201cDEVICE\u201d \u2014 z\u00edsk\u00e1me obraz FS z DEVICE (flashe);<\/li>\n<li>.\\\/Read.sh \u201cKEY\u201d 'MARKER' \u2014 vytvo\u0159\u00edme virtu\u00e1ln\u00ed prost\u0159ed\u00ed, st\u00e1hneme pot\u0159ebn\u00e9 knihovny a spust\u00edme skript na \u010dten\u00ed;<\/li>\n<li>V aktu\u00e1ln\u00edm adres\u00e1\u0159i otev\u0159eme soubor Read \u2013 to je pr\u00e1v\u011b zakryt\u00e1 informace.<\/li>\n<\/ol>\n<p><\/p>\n<h3 id=\"zaklyuchenie\">Z\u00e1v\u011br<\/h3>\n<p><\/p>\n<p>Tato metoda steganografie pravd\u011bpodobn\u011b pot\u0159ebuje vylep\u0161en\u00ed, dal\u0161\u00ed testov\u00e1n\u00ed a roz\u0161\u00ed\u0159en\u00ed na popul\u00e1rn\u011bj\u0161\u00ed souborov\u00e9 syst\u00e9my, jako jsou <noindex><a rel=\"nofollow\" href=\"https:\/\/ru.wikipedia.org\/wiki\/FAT32\">Fat32<\/a><\/noindex>, <noindex><a rel=\"nofollow\" href=\"https:\/\/ru.wikipedia.org\/wiki\/NTFS\">NTFS<\/a><\/noindex> a <noindex><a rel=\"nofollow\" href=\"https:\/\/ru.wikipedia.org\/wiki\/Ext4\">ext4.<\/a><\/noindex>.<br \/>\nAle c\u00edlem t\u00e9to pr\u00e1ce bylo uk\u00e1zat princip, pomoc\u00ed kter\u00e9ho lze prov\u00e9st skryt\u00e9 ukl\u00e1d\u00e1n\u00ed informac\u00ed do souborov\u00e9ho syst\u00e9mu.<br \/>\nS pomoc\u00ed podobn\u00fdch algoritm\u016f lze bezpe\u010dn\u011b ukl\u00e1dat informace, a pokud je mo\u017en\u00e9 takov\u00fd syst\u00e9m prolomit p\u0159i znalosti kl\u00ed\u010de, a\u010dkoliv p\u0159es velmi dlouh\u00fd algoritmus, bez znalosti kl\u00ed\u010de se mi tento syst\u00e9m jev\u00ed jako zcela odoln\u00fd; nicm\u00e9n\u011b to m\u016f\u017ee b\u00fdt d\u016fvod k samostatn\u00e9mu \u010dl\u00e1nku.<\/p>\n<p><\/p>\n<p>Ve\u0161ker\u00fd k\u00f3d je naps\u00e1n v jazyce Python verze 3.5.2. <noindex><a rel=\"nofollow\" href=\"https:\/\/youtu.be\/FEAE3_xDKkA\">P\u0159\u00edklad pr\u00e1ce<\/a><\/noindex> je uveden na m\u00e9m youtube kan\u00e1le. Kompletn\u00ed k\u00f3d projektu je um\u00edst\u011bn na <noindex><a rel=\"nofollow\" href=\"https:\/\/github.com\/MalahovMV\/Ext2Stego\">github<\/a><\/noindex>.<br \/>\n(Ano, v\u00edm, \u017ee pro produk\u010dn\u00ed verzi je pot\u0159eba ps\u00e1t na n\u011b\u010dem \u201erychl\u00e9m\u201c, nap\u0159\u00edklad v C \ud83d\ude09 )<br \/>\nV t\u00e9to implementaci nesm\u00ed velikost vstupn\u00edho souboru pro steganografii p\u0159ekro\u010dit 1000 kB.<\/p>\n<p><\/p>\n<p>Chci pod\u011bkovat u\u017eivateli <noindex><a rel=\"nofollow\" href=\"https:\/\/habrahabr.ru\/users\/pavelmstu\/\" class=\"user_link\">PavelMSTU<\/a><\/noindex> za cenn\u00e9 rady p\u0159i pl\u00e1nov\u00e1n\u00ed v\u00fdzkumu a doporu\u010den\u00ed k sestaven\u00ed \u010dl\u00e1nku.<\/p>\n<p>Zdroj: <a content=\"nofollow\" rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/post\/347604\/\">habr.com<\/a><\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"<p>\u041f\u0440\u0438\u0432\u0435\u0442, \u0425\u0430\u0431\u0440. \u0425\u043e\u0447\u0443 \u043f\u0440\u0435\u0434\u0441\u0442\u0430\u0432\u0438\u0442\u044c \u0432\u0430\u043c \u043d\u0435\u0431\u043e\u043b\u044c\u0448\u043e\u0439 \u043f\u0440\u043e\u0435\u043a\u0442 \u043f\u043e \u0441\u0442\u0435\u0433\u0430\u043d\u043e\u0433\u0440\u0430\u0444\u0438\u0438, \u0441\u0434\u0435\u043b\u0430\u043d\u043d\u044b\u0439 \u0432 \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0435 \u043e\u0442 \u0443\u0447\u0435\u0431\u044b \u0432\u0440\u0435\u043c\u044f. \u042f \u0441\u0434\u0435\u043b\u0430\u043b \u043f\u0440\u043e\u0435\u043a\u0442 \u043f\u043e \u0441\u043a\u0440\u044b\u0442\u043e\u043c\u0443 \u0445\u0440\u0430\u043d\u0435\u043d\u0438\u044e \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u0438 \u0432 \u0444\u0430\u0439\u043b\u043e\u0432\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u0435 (\u0434\u0430\u043b\u0435\u0435 \u0424\u0421). \u042d\u0442\u043e \u043c\u043e\u0436\u043d\u043e \u043f\u0440\u0438\u043c\u0435\u043d\u0438\u0442\u044c \u0434\u043b\u044f \u043a\u0440\u0430\u0436\u0438 \u043a\u043e\u043d\u0444\u0438\u0434\u0435\u043d\u0446\u0438\u0430\u043b\u044c\u043d\u043e\u0439 \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u0438 \u0432 \u043e\u0431\u0440\u0430\u0437\u043e\u0432\u0430\u0442\u0435\u043b\u044c\u043d\u044b\u0445 \u0446\u0435\u043b\u044f\u0445. \u0412 \u0432\u0438\u0434\u0435 \u043e\u043f\u044b\u0442\u043d\u043e\u0433\u043e \u043e\u0431\u0440\u0430\u0437\u0446\u0430 \u0431\u044b\u043b\u0430 \u0432\u044b\u0431\u0440\u0430\u043d\u0430 \u0432\u0435\u0441\u044c\u043c\u0430 \u0441\u0442\u0430\u0440\u0435\u043d\u044c\u043a\u0430\u044f \u043b\u0438\u043d\u0443\u043a\u0441\u043e\u0432\u0430\u044f \u0424\u0421 ext2. \u0420\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u044f \u0421\u043e\u043e\u0431\u0440\u0430\u0436\u0435\u043d\u0438\u044f \u043e \u0440\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438 \u0415\u0441\u043b\u0438 \u0445\u043e\u0440\u043e\u0448\u043e &#171;\u0440\u0430\u0437\u0434\u0440\u0430\u043a\u043e\u043d\u0438\u0442\u044c&#187; [&hellip;]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":23051,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[688],"tags":[],"class_list":["post-31080","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-administrirovanie"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 5.0.3 - aioseo.com -->\n\t<meta name=\"description\" content=\"\u041f\u0440\u0438\u0432\u0435\u0442, \u0425\u0430\u0431\u0440.\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<meta name=\"author\" content=\"Yuri Gagarin\"\/>\n\t<link rel=\"canonical\" href=\"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/steganografiya-v-fajlovoj-sisteme\" \/>\n\t\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 5.0.3\" \/>\n\t\t<meta property=\"og:locale\" content=\"cs_CZ\" \/>\n\t\t<meta property=\"og:site_name\" content=\"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"\ud83e\udd47\u0421\u0442\u0435\u0433\u0430\u043d\u043e\u0433\u0440\u0430\u0444\u0438\u044f \u0432 \u0444\u0430\u0439\u043b\u043e\u0432\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u0435 | ProHoster\" \/>\n\t\t<meta property=\"og:description\" content=\"\u041f\u0440\u0438\u0432\u0435\u0442, \u0425\u0430\u0431\u0440.\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/steganografiya-v-fajlovoj-sisteme\" \/>\n\t\t<meta property=\"og:image\" content=\"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg\" \/>\n\t\t<meta property=\"og:image:secure_url\" content=\"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg\" \/>\n\t\t<meta property=\"og:image:width\" content=\"350\" \/>\n\t\t<meta property=\"og:image:height\" content=\"350\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2019-10-31T18:39:19+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2019-10-31T18:39:19+00:00\" \/>\n\t\t<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/prohoster\" \/>\n\t\t<meta property=\"article:author\" content=\"https:\/\/www.facebook.com\/prohoster\" \/>\n\t\t<!-- All in One SEO -->\n\n","aioseo_head_json":{"title":"\ud83e\udd47Steganografie v souborov\u00e9m syst\u00e9mu | ProHoster","description":"Ahoj, Habr.","canonical_url":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/steganografiya-v-fajlovoj-sisteme","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"cs_CZ","og:site_name":"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b","og:type":"article","og:title":"\ud83e\udd47\u0421\u0442\u0435\u0433\u0430\u043d\u043e\u0433\u0440\u0430\u0444\u0438\u044f \u0432 \u0444\u0430\u0439\u043b\u043e\u0432\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u0435 | ProHoster","og:description":"\u041f\u0440\u0438\u0432\u0435\u0442, \u0425\u0430\u0431\u0440.","og:url":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/steganografiya-v-fajlovoj-sisteme","og:image":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:secure_url":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:width":350,"og:image:height":350,"article:published_time":"2019-10-31T18:39:19+00:00","article:modified_time":"2019-10-31T18:39:19+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":{"post_id":"31080","title":null,"description":null,"keywords":null,"keyphrases":null,"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"default","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":null,"og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":false,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"","isEnabled":true},"graphs":[]},"schema_type":null,"schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":null,"robots_max_videopreview":null,"robots_max_imagepreview":"large","priority":null,"frequency":null,"local_seo":null,"seo_analyzer_scan_date":"2026-01-21 04:26:19","breadcrumb_settings":null,"limit_modified_date":false,"reviewed_by":null,"ai":null,"created":"2021-03-01 03:22:35","updated":"2026-01-21 04:26:19","focus_keyword":null,"additional_keywords":null,"truseo_locale":null},"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/31080","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/comments?post=31080"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/31080\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media\/23051"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media?parent=31080"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/categories?post=31080"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/tags?post=31080"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}