{"id":35074,"date":"2019-10-31T22:02:11","date_gmt":"2019-10-31T19:02:11","guid":{"rendered":"https:\/\/prohoster.info\/blog\/kak-apple-privatno-najdyot-v-oflajne-vashe-poteryannoe-ustrojstvo\/"},"modified":"2019-10-31T22:02:11","modified_gmt":"2019-10-31T19:02:11","slug":"kak-apple-privatno-najdyot-v-oflajne-vashe-poteryannoe-ustrojstvo","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/kak-apple-privatno-najdyot-v-oflajne-vashe-poteryannoe-ustrojstvo","title":{"rendered":"Jak Apple (soukrom\u011b) najde va\u0161e ztracen\u00e9 za\u0159\u00edzen\u00ed offline?","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"<p>V pond\u011bl\u00ed na konferenci WWDC p\u0159edstavila spole\u010dnost Apple <noindex><a rel=\"nofollow\" href=\"https:\/\/www.wired.com\/story\/apple-find-my-cryptography-bluetooth\/\">p\u0159edstavila skv\u011blou novou funkci s n\u00e1zvem \u201eNajdi m\u016fj&#187;<\/a><\/noindex>. Na rozd\u00edl od standardn\u00edho <noindex><a rel=\"nofollow\" href=\"https:\/\/www.apple.com\/icloud\/find-my-iphone\/\">\u201eNaj\u00edt m\u016fj iPhone\u201c<\/a><\/noindex>, kter\u00e1 spol\u00e9h\u00e1 na infrastrukturu mobiln\u00edch s\u00edt\u00ed a GPS ztracen\u00e9ho za\u0159\u00edzen\u00ed, funkce \u201eNajdi m\u011b\u201c dok\u00e1\u017ee naj\u00edt i za\u0159\u00edzen\u00ed <i>bez<\/i> bez SIM karty a GPS. Nap\u0159\u00edklad notebooky, nebo dokonce <noindex><a rel=\"nofollow\" href=\"https:\/\/www.theverge.com\/circuitbreaker\/2019\/6\/4\/18652116\/apple-tag-tile-location-tracking-bluetooth-hardware-hint-ios-13-beta\">\u201ehloup\u00e9\u201c lokaliza\u010dn\u00ed \u0161t\u00edtky<\/a><\/noindex>, p\u0159ipevn\u011bn\u00e9 k jak\u00e9mukoli p\u0159edm\u011btu (Apple to nazna\u010dila pouze v \u0161irok\u00e9m slova smyslu).<\/p>\n<p>My\u0161lenka spo\u010d\u00edv\u00e1 v tom, aby se cel\u00e1 st\u00e1vaj\u00edc\u00ed s\u00ed\u0165 iPhon\u016f prom\u011bnila v rozs\u00e1hl\u00fd crowdsourcingov\u00fd syst\u00e9m pro sledov\u00e1n\u00ed okoln\u00edch objekt\u016f. Ka\u017ed\u00fd aktivn\u00ed iPhone bude neust\u00e1le sledovat sign\u00e1ly BLE, kter\u00e9 poch\u00e1zej\u00ed z jin\u00fdch za\u0159\u00edzen\u00ed. Kdy\u017e najde jeden z t\u011bchto sign\u00e1l\u016f, ozna\u010d\u00ed paket sv\u00fdmi GPS sou\u0159adnicemi - a ode\u0161le je na servery Apple. To je skv\u011bl\u00e9 pro lidi jako j\u00e1, kte\u0159\u00ed neust\u00e1le ztr\u00e1cej\u00ed v\u011bci: pokud nech\u00e1m sv\u016fj batoh v turistick\u00e9m autobusu v \u010c\u00edn\u011b, n\u011bkdo se brzy na jeho sign\u00e1l naraz\u00ed - a okam\u017eit\u011b zjist\u00edm, kde ho naj\u00edt.<\/p>\n<p>(Je t\u0159eba poznamenat, \u017ee tuto my\u0161lenku nevymyslela Apple. Ve skute\u010dnosti na tomto poli u\u017e n\u011bjakou dobu pracuj\u00ed spole\u010dnosti jako <noindex><a rel=\"nofollow\" href=\"https:\/\/www.thetileapp.com\/en-us\/\">Tile<\/a><\/noindex> . A ano, m\u011bly by se ob\u00e1vat o sv\u00e9 podnik\u00e1n\u00ed).<br \/>\n<noindex><a rel=\"nofollow\" name=\"habracut\"><\/a><\/noindex><br \/>\nPokud v\u00e1s popis v\u00fd\u0161e neoslnil, dovolte mi polo\u017eit ot\u00e1zku, kterou byste m\u011bli polo\u017eit: <i>jak tento syst\u00e9m ochr\u00e1n\u00ed p\u0159ed masov\u00fdmi poru\u0161en\u00edmi soukrom\u00ed?<\/i><\/p>\n<p>Vyjmenujme mo\u017en\u00e9 probl\u00e9my:<\/p>\n<ul>\n<li>Pokud za\u0159\u00edzen\u00ed neust\u00e1le vys\u00edl\u00e1 sign\u00e1l BLE, kter\u00fd jednozna\u010dn\u00fdm zp\u016fsobem identifikuje, m\u00e1 nyn\u00ed ka\u017ed\u00fd (je\u0161t\u011b jeden) zp\u016fsob, jak v\u00e1s sledovat. Marketers ji\u017e k tomu pou\u017e\u00edvaj\u00ed MAC adresy WiFi a Bluetooth, a funkce <i>Najdi m\u011b<\/i> vytv\u00e1\u0159\u00ed dal\u0161\u00ed kan\u00e1l sledov\u00e1n\u00ed.\n<\/li>\n<li>Tak\u00e9 odhaluje ty, kte\u0159\u00ed <i>se \u00fa\u010dastn\u00ed<\/i> tohoto procesu. Nyn\u00ed tito lid\u00e9 budou pos\u00edlat Apple svou aktu\u00e1ln\u00ed polohu (mo\u017en\u00e1 to d\u011blaj\u00ed u\u017e te\u010f). Ale nyn\u00ed budou muset sd\u00edlet tyto informace <i>tak\u00e9<\/i> s ciz\u00edmi lidmi, kte\u0159\u00ed \u201eztr\u00e1cej\u00ed\u201c sv\u00e1 za\u0159\u00edzen\u00ed. To se m\u016f\u017ee \u0161patn\u011b skon\u010dit.\n<\/li>\n<li>Podvodn\u00edci tak\u00e9 mohou spustit aktivn\u00ed \u00fatoky, p\u0159i nich\u017e fal\u0161uj\u00ed polohu va\u0161eho za\u0159\u00edzen\u00ed. I kdy\u017e se to zd\u00e1 nepravd\u011bpodobn\u00e9, lid\u00e9 v\u017edy dok\u00e1\u017e\u00ed p\u0159ekvapit.<\/li>\n<\/ul>\n<p>\nDobr\u00e1 zpr\u00e1va je, \u017ee Apple tvrd\u00ed, \u017ee syst\u00e9m skute\u010dn\u011b zaji\u0161\u0165uje spolehliv\u00e9 soukrom\u00ed d\u00edky chytr\u00e9mu pou\u017eit\u00ed kryptografie. Ale, jak b\u00fdv\u00e1 obvykl\u00e9, odm\u00edtli poskytnout <i>detaily implementace<\/i>. Andy Greenberg v Wired popsal \u010d\u00e1ste\u010dnou <noindex><a rel=\"nofollow\" href=\"https:\/\/www.wired.com\/story\/apple-find-my-cryptography-bluetooth\/\">technickou realizaci<\/a><\/noindex> slovy Apple, kter\u00e1 n\u00e1m mnoho objas\u0148uje. Bohu\u017eel, tento popis st\u00e1le zanech\u00e1v\u00e1 obrovsk\u00e9 mezery. Tyto mezery se chyst\u00e1m zaplnit a nab\u00eddnout nejpravd\u011bpodobn\u011bj\u0161\u00ed popis toho, co Apple skute\u010dn\u011b d\u011bl\u00e1.<\/p>\n<p>Velk\u00e1 v\u00fdhrada: mnoh\u00e9 se m\u016f\u017ee uk\u00e1zat jako zcela \u0161patn\u00e9. \u010cl\u00e1nek ur\u010dit\u011b aktualizuji, jakmile Apple poskytne v\u00edce informac\u00ed.<\/p>\n<h1>N\u011bkter\u00e9 z\u00e1kladn\u00ed probl\u00e9my<\/h1>\n<p>\nAbychom ilustrovali sc\u00e9n\u00e1\u0159, mus\u00edme do obrazu vlo\u017eit n\u011bkolik za\u0159\u00edzen\u00ed. Pro inspiraci vezmeme televizn\u00ed seri\u00e1l z 50. let \u201eLassie\u201c.<\/p>\n<p>Prvn\u00ed za\u0159\u00edzen\u00ed, kter\u00e9 nazveme <b>Timmy<\/b>, je \"ztraceno\". M\u00e1 <b>Timmy<\/b> BLE vys\u00edla\u010d, ale \u017e\u00e1dn\u00e9 GPS ani p\u0159ipojen\u00ed k internetu. Na\u0161t\u011bst\u00ed se ji\u017e sp\u00e1roval s druh\u00fdm za\u0159\u00edzen\u00edm nazvan\u00fdm <b>Ruth<\/b>, kter\u00e1 ho chce naj\u00edt. Na\u0161\u00edm hlavn\u00edm hrdinou je <b>Lassie<\/b>: je to iPhone n\u00e1hodn\u00e9ho (a o tom nev\u011bdom\u00e9ho) cizince, kter\u00fd m\u00e1 (p\u0159edpokl\u00e1dejme) alespo\u0148 ob\u010dasn\u00e9 p\u0159ipojen\u00ed k internetu a spolehliv\u00e9 GPS. A nav\u00edc je Lassie velmi hodn\u00e1 holka. S\u00ed\u0165ov\u00e1 za\u0159\u00edzen\u00ed spolu interaguj\u00ed p\u0159es iCloud servery Apple, jak je zn\u00e1zorn\u011bno n\u00ed\u017ee:<\/p>\n<p><img decoding=\"async\" alt=\"Jak Apple (soukrom\u011b) najde va\u0161e ztracen\u00e9 za\u0159\u00edzen\u00ed offline?\" src=\"\/wp-content\/uploads\/2019\/06\/e583ee12f947c544f581d34b5df7e6cf.png\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<br \/>\n(Proto\u017ee <b>Timmy<\/b> a <b>Ruth<\/b> mus\u00ed b\u00fdt sp\u00e1rov\u00e1na p\u0159edem, pravd\u011bpodobn\u011b pat\u0159\u00ed ob\u011b stejn\u00e9mu \u010dlov\u011bku. Zm\u00ednil jsem, \u017ee budete muset koupit <i>dva<\/i> za\u0159\u00edzen\u00ed Apple, aby syst\u00e9m fungoval? To Apple rozhodn\u011b vyhovuje).<\/p>\n<p>Zkoum\u00e1me bezpe\u010dnostn\u00ed syst\u00e9m, tak\u017ee prvn\u00ed ot\u00e1zka zn\u00ed: <i>kdo je \u0161patn\u00fd chlapec?<\/i>? \u0412 \u044d\u0442\u043e\u0439 \u0441\u0438\u0442\u0443\u0430\u0446\u0438\u0438 \u043e\u0442\u0432\u0435\u0442 \u043d\u0435\u043f\u0440\u0438\u044f\u0442\u043d\u044b\u0439: <i>potenci\u00e1ln\u00edm zlo\u010dincem m\u016f\u017ee b\u00fdt kdokoli<\/i>. Proto je probl\u00e9m tak zaj\u00edmav\u00fd.<\/p>\n<h1>Udr\u017een\u00ed anonymity Timmyho<\/h1>\n<p>\nNejd\u016fle\u017eit\u011bj\u0161\u00edm aspektem syst\u00e9mu je, \u017ee se nesm\u00ed umo\u017enit ciz\u00edm osob\u00e1m sledovat <b>Timmy<\/b>, zejm\u00e9na kdy\u017e nen\u00ed ztracen\u00fd. To vylu\u010duje n\u011bkter\u00e1 docela z\u0159ejm\u00e1 \u0159e\u0161en\u00ed, nap\u0159\u00edklad kdy\u017e se za\u0159\u00edzen\u00ed <b>Timmy<\/b> prost\u011b ozve: <i>\"Ahoj, jmenuji se Timmy, pros\u00edm, zavolejte m\u00e9 m\u00e1m\u011b Ruth a \u0159ekn\u011bte j\u00ed, \u017ee jsem ztracen\u00fd\"<\/i>. To tak\u00e9 vylu\u010duje prakticky jak\u00fdkoli nem\u011bnn\u00fd statick\u00fd identifik\u00e1tor, dokonce i nepr\u016fhledn\u00fd a vypadaj\u00edc\u00ed n\u00e1hodn\u011b.<\/p>\n<p>Posledn\u00ed po\u017eadavek je zalo\u017een na smutn\u00e9 zku\u0161enosti slu\u017eeb, kter\u00e9 zneu\u017e\u00edvaj\u00ed statick\u00e9 identifik\u00e1tory (nap\u0159\u00edklad, <noindex><a rel=\"nofollow\" href=\"https:\/\/www.ftc.gov\/news-events\/blogs\/techftc\/2014\/02\/my-phone-your-service\">va\u0161i<\/a><\/noindex> <noindex><a rel=\"nofollow\" href=\"https:\/\/medium.com\/@DanieleMiorandi\/i-lie-you-lie-everybody-lies-wifi-tracking-in-the-era-of-mac-randomization-2ab147857b24\">MAC adresu WiFi<\/a><\/noindex>) pro sledov\u00e1n\u00ed pohybu za\u0159\u00edzen\u00ed. Apple <noindex><a rel=\"nofollow\" href=\"https:\/\/arxiv.org\/abs\/1703.02874v1\">s sm\u00ed\u0161en\u00fdm \u00fasp\u011bchem<\/a><\/noindex> bojuje s t\u00edmto sledov\u00e1n\u00edm pomoc\u00ed randomizace identifik\u00e1tor\u016f, jako jsou MAC adresy. Pokud Apple p\u0159id\u00e1 statick\u00fd identifik\u00e1tor pro sledov\u00e1n\u00ed pro 'Find My', v\u0161echny probl\u00e9my se pouze zhor\u0161\u00ed.<\/p>\n<p>Tento po\u017eadavek znamen\u00e1, \u017ee jak\u00e9koli zpr\u00e1vy p\u0159en\u00e1\u0161en\u00e9 <b>Timmy<\/b>, mus\u00ed b\u00fdt nepr\u016fhledn\u00e9. Nav\u00edc by obsah t\u011bchto zpr\u00e1v m\u011bl relativn\u011b \u010dasto m\u011bnit na nov\u00e9 hodnoty, kter\u00e9 nelze p\u0159i\u0159adit ke star\u00fdm. Jeden z o\u010dividn\u00fdch zp\u016fsob\u016f, jak sp\u00e1rovan\u00e9 za\u0159\u00edzen\u00ed rozpoznat takov\u00e9 zpr\u00e1vy, je p\u0159im\u011bt <b>Timmy<\/b> a <b>Ruth<\/b> jednat s dlouh\u00fdm seznamem n\u00e1hodn\u00fdch '<noindex><a rel=\"nofollow\" href=\"https:\/\/en.wikipedia.org\/wiki\/Pseudonym\">p\u0159ezd\u00edvek<\/a><\/noindex>' pro <b>Timmy<\/b>, a nechat <b>Timmy<\/b> ka\u017ed\u00fdkr\u00e1t vybrat jin\u00fd.<\/p>\n<p>To opravdu pom\u00e1h\u00e1. Ka\u017ed\u00fdkr\u00e1t, kdy\u017e <b>Lassie<\/b> vid\u00ed n\u011bjak\u00e9 (nezn\u00e1m\u00e9) za\u0159\u00edzen\u00ed, kter\u00e9 p\u0159en\u00e1\u0161\u00ed identifik\u00e1tor, nebude v\u011bd\u011bt, zda pat\u0159\u00ed <b>Timmy<\/b>: ale m\u016f\u017ee ho poslat na servery Apple spolu se svou vlastn\u00ed GPS polohou. V p\u0159\u00edpad\u011b, \u017ee <b>Timmy<\/b> se ztrat\u00ed, <b>Ruth<\/b> m\u016f\u017ee po\u017e\u00e1dat Apple, aby na\u0161la v\u0161echny mo\u017en\u00e9 p\u0159ezd\u00edvky. <b>Timmy<\/b>V t\u00e9to situaci nikdo mimo Apple se o tomto seznamu nedozv\u00ed, a dokonce ani Apple se o n\u011bm dozv\u00ed pouze tehdy, kdy\u017e se n\u011bkdo ztrat\u00ed, tak\u017ee tento p\u0159\u00edstup zabra\u0148uje v\u011bt\u0161in\u011b mo\u017enost\u00ed sledov\u00e1n\u00ed.<\/p>\n<p>O n\u011bco efektivn\u011bj\u0161\u00ed zp\u016fsob, jak tuto my\u0161lenku realizovat, je pou\u017e\u00edt kryptografickou funkci (nap\u0159. MAC nebo hash funkci), aby se vygeneroval seznam p\u0159ezd\u00edvek z jednoho kr\u00e1tk\u00e9ho 'seed', jeho\u017e kopii uchov\u00e1v\u00e1 <b>Timmy<\/b> a <b>Ruth<\/b>. To je dobr\u00e9, proto\u017ee to sni\u017euje objem uchov\u00e1van\u00fdch dat. Ale aby na\u0161la <b>Timmy<\/b>, <b>Ruth<\/b> , stejn\u011b mus\u00ed poslat v\u0161echny p\u0159ezd\u00edvky \u2013 nebo seed \u2013 spole\u010dnosti Apple, kter\u00e1 mus\u00ed hledat ka\u017edou p\u0159ezd\u00edvku ve sv\u00e9 datab\u00e1zi.<\/p>\n<h1>Skr\u00fdv\u00e1n\u00ed polohy Lassie<\/h1>\n<p>\nOpopisovan\u00fd p\u0159\u00edstup s p\u0159ezd\u00edvkami by m\u011bl dob\u0159e skr\u00fdvat <i>identitu<\/i> <b>Timmy<\/b> od <b>Lassie<\/b> i p\u0159ed Applem (a\u017e do okam\u017eiku, kdy <b>Ruth<\/b> za\u010dne hledat). Nicm\u00e9n\u011b existuje velk\u00e1 nev\u00fdhoda: <i>to neskr\u00fdv\u00e1 GPS sou\u0159adnice <b>Lassie<\/b><\/i>.<\/p>\n<p>To je \u0161patn\u00e9, alespo\u0148 z n\u011bkolika d\u016fvod\u016f. Ka\u017ed\u00fdkr\u00e1t, kdy\u017e <b>Lassie<\/b> pokud za\u0159\u00edzen\u00ed s BLE sign\u00e1lem zjist\u00ed jak\u00e9koli za\u0159\u00edzen\u00ed, m\u011blo by odeslat sv\u00e9 aktu\u00e1ln\u00ed um\u00edst\u011bn\u00ed na servery Apple (spolu s pseudonymem, kter\u00fd vid\u00ed). To znamen\u00e1, \u017ee <b>Lassie<\/b> neust\u00e1le informuje Apple, kde se nach\u00e1z\u00ed. A co v\u00edc, i kdy\u017e Apple slibuje, \u017ee nebude uchov\u00e1vat identit\u00e9 <b>Lassie<\/b>, v\u00fdsledkem v\u0161ech t\u011bchto zpr\u00e1v je obrovsk\u00e1 centralizovan\u00e1 datab\u00e1ze, kter\u00e1 ukazuje v\u0161echna GPS um\u00edst\u011bn\u00ed, kde bylo zji\u0161t\u011bno <i>jak\u00e9koli<\/i> za\u0159\u00edzen\u00ed Apple.<\/p>\n<p>Vezm\u011bte na v\u011bdom\u00ed, \u017ee samotn\u00fd tento soubor dat poskytuje velk\u00e9 mno\u017estv\u00ed informac\u00ed. Ano, identifik\u00e1tory za\u0159\u00edzen\u00ed mohou b\u00fdt pseudonymy \u2014 ale to ned\u011bl\u00e1 informace bezcenn\u00fdmi. Nap\u0159\u00edklad pokud <i>n\u011bjak\u00e9<\/i> za\u0159\u00edzen\u00ed Apple vys\u00edl\u00e1 stejn\u00e9 sou\u0159adnice ka\u017ed\u00fd ve\u010der, ukazuje to pravd\u011bpodobnou adresu bydli\u0161t\u011b u\u017eivatele.<\/p>\n<p>Z\u0159ejm\u00fd zp\u016fsob, jak zabr\u00e1nit odhalen\u00ed t\u011bchto dat Apple, je \u0161ifrovat je, aby informace vid\u011bli pouze ti, kdo opravdu <i>je t\u0159eba<\/i> pot\u0159ebuj\u00ed zn\u00e1t um\u00edst\u011bn\u00ed za\u0159\u00edzen\u00ed. Pokud <b>Lassie<\/b> obdr\u017e\u00ed zpr\u00e1vu od <b>Timmy<\/b>, jedin\u00fd, kdo skute\u010dn\u011b pot\u0159ebuje zn\u00e1t um\u00edst\u011bn\u00ed <b>Lassie<\/b>, to je <b>Ruth<\/b>. Aby tuto informaci uchoval v tajnosti, <b>Lassie<\/b> by m\u011bl \u0161ifrovat sv\u00e9 sou\u0159adnice ve\u0159ejn\u00fdm kl\u00ed\u010dem <b>Ruth<\/b>.<\/p>\n<p>Samoz\u0159ejm\u011b vyvst\u00e1v\u00e1 ot\u00e1zka: jak <b>Lassie<\/b> z\u00edsk\u00e1 kl\u00ed\u010d <b>Ruth<\/b>? \u041e\u0447\u0435\u0432\u0438\u0434\u043d\u043e\u0435 \u0440\u0435\u0448\u0435\u043d\u0438\u0435 \u0434\u043b\u044f <b>Timmy<\/b>\u00a0\u2014 k\u0159i\u010den\u00edm ve\u0159ejn\u00e9ho kl\u00ed\u010de <b>Ruth<\/b> v ka\u017ed\u00e9m sv\u00e9m vys\u00edl\u00e1n\u00ed. Ale to by vytvo\u0159ilo statick\u00fd identifik\u00e1tor, kter\u00fd by op\u011bt umo\u017enil sledov\u00e1n\u00ed <b>Timmy<\/b>.<\/p>\n<p>Aby se tento probl\u00e9m vy\u0159e\u0161il, pot\u0159ebuje <b>Ruth<\/b> to bylo <i>mnoho nep\u0159idru\u017een\u00fdch ve\u0159ejn\u00fdch kl\u00ed\u010d\u016f<\/i>, aby <b>Timmy<\/b> mohl vyd\u00e1vat r\u016fzn\u00e9 kl\u00ed\u010de s ka\u017ed\u00fdm vys\u00edl\u00e1n\u00edm. Jednou z mo\u017enost\u00ed je donutit <b>Ruth<\/b> a <b>Timmy<\/b> generovat mnoho r\u016fzn\u00fdch p\u00e1r\u016f kl\u00ed\u010d\u016f (nebo generovat mnoho takov\u00fdch p\u00e1r\u016f ze spole\u010dn\u00e9ho semene). Ale to je otravn\u00e9 a <b>Ruth<\/b> by bylo nutn\u00e9 uchov\u00e1vat mnoho tajn\u00fdch kl\u00ed\u010d\u016f. A identifik\u00e1tory zm\u00edn\u011bn\u00e9 v p\u0159edchoz\u00ed kapitole mohou b\u00fdt z\u00edsk\u00e1ny hashov\u00e1n\u00edm ka\u017ed\u00e9ho ve\u0159ejn\u00e9ho kl\u00ed\u010de.<\/p>\n<p>O n\u011bco lep\u0161\u00ed p\u0159\u00edstup (kter\u00fd Apple m\u016f\u017ee nebo nemus\u00ed pou\u017e\u00edt) p\u0159edpokl\u00e1d\u00e1 <i>randomizaci<\/i> kl\u00ed\u010d\u016f. To je vlastnost n\u011bkter\u00fdch kryptosyst\u00e9m\u016f, jako jsou <noindex><a rel=\"nofollow\" href=\"https:\/\/en.wikipedia.org\/wiki\/ElGamal_encryption\">Elgamal<\/a><\/noindex>: umo\u017e\u0148uje jak\u00e9koli stran\u011b randomizovat ve\u0159ejn\u00fd kl\u00ed\u010d <noindex><a rel=\"nofollow\" href=\"https:\/\/crypto.stanford.edu\/~pgolle\/papers\/univrenc.pdf\">, tak\u017ee nebude nijak spojen s origin\u00e1lem. Nejlep\u0161\u00ed \u010d\u00e1st t\u00e9to funkce spo\u010d\u00edv\u00e1 v tom, \u017ee<\/a><\/noindex>jeden tajn\u00fd kl\u00ed\u010d nez\u00e1visle na tom, jak\u00e1 randomizovan\u00e1 verze jej\u00edho ve\u0159ejn\u00e9ho kl\u00ed\u010de byla pou\u017eita pro \u0161ifrov\u00e1n\u00ed. <b>Ruth<\/b> m\u016f\u017ee pou\u017e\u00edvat <i>jeden tajn\u00fd kl\u00ed\u010d, bez ohledu na to, kter\u00e1 n\u00e1hodn\u011b generovan\u00e1 verze jej\u00edho ve\u0159ejn\u00e9ho kl\u00ed\u010de byla pou\u017eita pro \u0161ifrov\u00e1n\u00ed<\/i>.<\/p>\n<p><img decoding=\"async\" alt=\"Jak Apple (soukrom\u011b) najde va\u0161e ztracen\u00e9 za\u0159\u00edzen\u00ed offline?\" src=\"\/wp-content\/uploads\/2019\/06\/f25b5a32e89883283fa6046c326751ca.png\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<br \/>\nV\u0161echny tyto faktory vedou k kone\u010dn\u00e9 my\u0161lence protokolu. V ka\u017ed\u00e9m p\u0159enosu <b>Timmy<\/b> p\u0159en\u00e1\u0161\u00ed nov\u00fd alias a randomizovanou kopii ve\u0159ejn\u00e9ho kl\u00ed\u010de <b>Ruth<\/b>. Kdy\u017e <b>Lassie<\/b> obdr\u017e\u00ed p\u0159enos, za\u0161ifruje sv\u00e9 GPS sou\u0159adnice ve\u0159ejn\u00fdm kl\u00ed\u010dem a ode\u0161le za\u0161ifrovanou zpr\u00e1vu do Apple. <b>Ruth<\/b> m\u016f\u017ee poslat aliasy <b>Timmy<\/b> na servery Apple, a pokud Apple najde shodu, bude schopna z\u00edskat a de\u0161ifrovat GPS sou\u0159adnice.<\/p>\n<h1>\u0158e\u0161\u00ed to v\u0161echny probl\u00e9my?<\/h1>\n<p>\nNep\u0159\u00edjemn\u00e1 v\u011bc je, \u017ee neexistuje dokonal\u00e9 \u0159e\u0161en\u00ed pro mnoho podivn\u00fdch mezn\u00edch situac\u00ed. Nap\u0159\u00edklad, co kdy\u017e m\u00e1 <b>Timmy<\/b> \u0161patn\u00e9 \u00famysly a chce donutit <b>Lassie<\/b> odhalit svou polohu Apple? Co kdy\u017e se pan Smith pokus\u00ed un\u00e9st <b>Lassie<\/b>?<\/p>\n<p>Nakonec se odpov\u011b\u010f na tuto ot\u00e1zku ohledn\u011b toho, co jsme ud\u011blali pro to nejlep\u0161\u00ed, z\u00fa\u017e\u00ed na fakt, \u017ee jsme ud\u011blali v\u0161e, co bylo mo\u017en\u00e9: jak\u00e9koli zbyl\u00e9 probl\u00e9my by m\u011bly b\u00fdt vylou\u010deny ze sch\u00e9matu hrozby. N\u011bkdy dokonce i Lassie v\u00ed, kdy p\u0159estat.<br \/>\n<br \/>Zdroj: <a content=\"nofollow\" rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/post\/455054\/\">habr.com<\/a><\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"<p>\u0412 \u043f\u043e\u043d\u0435\u0434\u0435\u043b\u044c\u043d\u0438\u043a \u043d\u0430 \u043a\u043e\u043d\u0444\u0435\u0440\u0435\u043d\u0446\u0438\u0438 WWDC \u043a\u043e\u043c\u043f\u0430\u043d\u0438\u044f Apple \u043f\u0440\u0435\u0434\u0441\u0442\u0430\u0432\u0438\u043b\u0430 \u043a\u043b\u0430\u0441\u0441\u043d\u0443\u044e \u043d\u043e\u0432\u0443\u044e \u0444\u0443\u043d\u043a\u0446\u0438\u044e \u043f\u043e\u0434 \u043d\u0430\u0437\u0432\u0430\u043d\u0438\u0435\u043c \u201cFind My&#187;. \u0412 \u043e\u0442\u043b\u0438\u0447\u0438\u0435 \u043e\u0442 \u0441\u0442\u0430\u043d\u0434\u0430\u0440\u0442\u043d\u043e\u0439 \u00ab\u041d\u0430\u0439\u0442\u0438 \u043c\u043e\u0439 iPhone\u00bb, \u043a\u043e\u0442\u043e\u0440\u0430\u044f \u043f\u043e\u043b\u0430\u0433\u0430\u0435\u0442\u0441\u044f \u043d\u0430 \u0438\u043d\u0444\u0440\u0430\u0441\u0442\u0440\u0443\u043a\u0442\u0443\u0440\u0443 \u0441\u043e\u0442\u043e\u0432\u043e\u0439 \u0441\u0432\u044f\u0437\u0438 \u0438 GPS \u043f\u043e\u0442\u0435\u0440\u044f\u043d\u043d\u043e\u0433\u043e \u0443\u0441\u0442\u0440\u043e\u0439\u0441\u0442\u0432\u0430, \u0444\u0443\u043d\u043a\u0446\u0438\u044f \u00ab\u041d\u0430\u0439\u0434\u0438 \u043c\u0435\u043d\u044f\u00bb \u0441\u043f\u043e\u0441\u043e\u0431\u043d\u0430 \u043d\u0430\u0439\u0442\u0438 \u0434\u0430\u0436\u0435 \u0443\u0441\u0442\u0440\u043e\u0439\u0441\u0442\u0432\u0430 \u0431\u0435\u0437 \u0441\u0438\u043c-\u043a\u0430\u0440\u0442\u044b \u0438 GPS. \u041d\u0430\u043f\u0440\u0438\u043c\u0435\u0440, \u043d\u043e\u0443\u0442\u0431\u0443\u043a\u0438, \u0438\u043b\u0438 \u0434\u0430\u0436\u0435 \u00ab\u0442\u0443\u043f\u044b\u0435\u00bb \u043c\u0435\u0442\u043a\u0438 \u043b\u043e\u043a\u0430\u0446\u0438\u0438, \u043f\u0440\u0438\u043a\u0440\u0435\u043f\u043b\u0451\u043d\u043d\u044b\u0435 \u043a \u043b\u044e\u0431\u043e\u043c\u0443 \u043f\u0440\u0435\u0434\u043c\u0435\u0442\u0443 (Apple [&hellip;]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":26375,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[688],"tags":[],"class_list":["post-35074","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=\"\u0412 \u043f\u043e\u043d\u0435\u0434\u0435\u043b\u044c\u043d\u0438\u043a \u043d\u0430 \u043a\u043e\u043d\u0444\u0435\u0440\u0435\u043d\u0446\u0438\u0438 WWDC \u043a\u043e\u043c\u043f\u0430\u043d\u0438\u044f Apple \u043f\u0440\u0435\u0434\u0441\u0442\u0430\u0432\u0438\u043b\u0430 \u043a\u043b\u0430\u0441\u0441\u043d\u0443\u044e \u043d\u043e\u0432\u0443\u044e \u0444\u0443\u043d\u043a\u0446\u0438\u044e \u043f\u043e\u0434 \u043d\u0430\u0437\u0432\u0430\u043d\u0438\u0435\u043c \u201cFind.\" \/>\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\/kak-apple-privatno-najdyot-v-oflajne-vashe-poteryannoe-ustrojstvo\" \/>\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\u041a\u0430\u043a Apple (\u043f\u0440\u0438\u0432\u0430\u0442\u043d\u043e) \u043d\u0430\u0439\u0434\u0451\u0442 \u0432 \u043e\u0444\u043b\u0430\u0439\u043d\u0435 \u0432\u0430\u0448\u0435 \u043f\u043e\u0442\u0435\u0440\u044f\u043d\u043d\u043e\u0435 \u0443\u0441\u0442\u0440\u043e\u0439\u0441\u0442\u0432\u043e? 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