{"id":437,"date":"2024-10-03T21:58:03","date_gmt":"2024-10-03T13:58:03","guid":{"rendered":"https:\/\/jotaku.cn\/?p=437"},"modified":"2024-10-03T21:58:03","modified_gmt":"2024-10-03T13:58:03","slug":"%e5%9b%9b%e5%b7%9d%e6%9f%90%e5%8d%95%e4%bd%8d%e5%86%85%e9%83%a8%e8%b5%9b%e4%b8%80%e9%81%93crypto","status":"publish","type":"post","link":"https:\/\/jotaku.cn\/index.php\/2024\/10\/03\/%e5%9b%9b%e5%b7%9d%e6%9f%90%e5%8d%95%e4%bd%8d%e5%86%85%e9%83%a8%e8%b5%9b%e4%b8%80%e9%81%93crypto\/","title":{"rendered":"\u56db\u5ddd\u67d0\u5355\u4f4d\u5185\u90e8\u8d5b\u4e00\u9053Crypto"},"content":{"rendered":"\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p>\u597d\u4e45\u6ca1\u6c34\u6587\u7ae0\u4e86\uff0c\u8d34\u4e00\u7bc7\u4ee5\u524d\u505a\u8fc7\u7684\u4e00\u9053\u9898\u76ee<\/p>\n<\/blockquote>\n\n\n\n<h1 class=\"wp-block-heading\">Task<\/h1>\n\n\n\n<pre class=\"wp-block-code\"><code>from Crypto.Util.number import *\nfrom flag import p, q, a, b, c, d, e, flag\n\nassert p.bit_length() == 512\nassert q.bit_length() == 512\nn = p * q\nassert a * a + e * b * b == n\nassert c * c + e * d * d == n\n\nm = bytes_to_long(flag)\ncipher = pow(m, e, n)\nprint('n =', n)\nprint('cipher =', cipher)\nprint('a =', a)\nprint('b =', b)\nprint('c =', c)\nprint('d =', d)\n\n\"\"\"\nn = 60759060882959791909904396677188989949758090199603630243982902422381690538885036721260587316981956179159099537464766520810988299027308891716697721325694989187113132568281096643090555966502943628821584608317087986774067361766441006582461264783625589284748285132591500064467264821214540974749792006934616412217\ncipher = 20458653228553322014465307182393782250675128141639209159045300541287741675246921642347569059959881263633155911063532171465637193709348356233437155581027365642514135793800584667963139842701093152576878356429568990356697857264248093880916698956321511178224500312370845360786231377700287611408999899734512143183\na = 7794809868300816476939749391923181660663599092817735689970830403880360740950291069966802056703842257352942487715953634294627774900178116901736408438781725\nb = 19283995921825875899155714134110227538038032500196406129941198508864582000463560816723795975202107099295086076956040133684\nc = 7794809868300816476939748778965768208814733337627617321244638924271232070361166330324980435743037906985498772947115676315756364476413563742000304770717475\nd = 172332404813056620110912939211150875333966617506319147214329967023854401850532359816888852973202924631133349299841944983684\n\n\"\"\"<\/code><\/pre>\n\n\n\n<h1 class=\"wp-block-heading\">\u601d\u8def<\/h1>\n\n\n\n<p>e\u5f88\u597d\u6c42\uff0c\u95ee\u9898\u662f\u600e\u4e48\u5206\u89e3n<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\"   class=\"lazyload\" data-src=\"https:\/\/jotaku.cn\/wp-content\/uploads\/2024\/10\/\u56db\u5ddd\u6bd4\u8d5bwp\u914d\u56fe-1024x576.jpeg\" src=\"https:\/\/cdn.jsdelivr.net\/gh\/moezx\/cdn@3.0.2\/img\/svg\/loader\/trans.ajax-spinner-preloader.svg\" onerror=\"imgError(this)\"  alt=\"\" class=\"wp-image-439\" srcset=\"https:\/\/jotaku.cn\/wp-content\/uploads\/2024\/10\/\u56db\u5ddd\u6bd4\u8d5bwp\u914d\u56fe-1024x576.jpeg 1024w, https:\/\/jotaku.cn\/wp-content\/uploads\/2024\/10\/\u56db\u5ddd\u6bd4\u8d5bwp\u914d\u56fe-300x169.jpeg 300w, https:\/\/jotaku.cn\/wp-content\/uploads\/2024\/10\/\u56db\u5ddd\u6bd4\u8d5bwp\u914d\u56fe-768x432.jpeg 768w, https:\/\/jotaku.cn\/wp-content\/uploads\/2024\/10\/\u56db\u5ddd\u6bd4\u8d5bwp\u914d\u56fe.jpeg 1280w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure >\n<noscript><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/jotaku.cn\/wp-content\/uploads\/2024\/10\/\u56db\u5ddd\u6bd4\u8d5bwp\u914d\u56fe-1024x576.jpeg\" alt=\"\" class=\"wp-image-439\" srcset=\"https:\/\/jotaku.cn\/wp-content\/uploads\/2024\/10\/\u56db\u5ddd\u6bd4\u8d5bwp\u914d\u56fe-1024x576.jpeg 1024w, https:\/\/jotaku.cn\/wp-content\/uploads\/2024\/10\/\u56db\u5ddd\u6bd4\u8d5bwp\u914d\u56fe-300x169.jpeg 300w, https:\/\/jotaku.cn\/wp-content\/uploads\/2024\/10\/\u56db\u5ddd\u6bd4\u8d5bwp\u914d\u56fe-768x432.jpeg 768w, https:\/\/jotaku.cn\/wp-content\/uploads\/2024\/10\/\u56db\u5ddd\u6bd4\u8d5bwp\u914d\u56fe.jpeg 1280w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure><\/noscript>\n\n\n\n<p>\u76f8\u5173\u8bba\u6587<\/p>\n\n\n\n<p><a href=\"https:\/\/cs.uwaterloo.ca\/journals\/JIS\/VOL17\/Matthews\/matt10.pdf\" target=\"_blank\"  rel=\"nofollow\" >https:\/\/cs.uwaterloo.ca\/journals\/JIS\/VOL17\/Matthews\/matt10.pdf<\/a><\/p>\n\n\n\n<p>\u7c7b\u4f3c\u9898\u76ee\uff08plus\u7248<\/p>\n\n\n\n<p><a href=\"https:\/\/github.com\/Sarkoxed\/ctf-writeups\/tree\/master\/hacktm2023\/kaitenzushi\" target=\"_blank\"  rel=\"nofollow\" >https:\/\/github.com\/Sarkoxed\/ctf-writeups\/tree\/master\/hacktm2023\/kaitenzushi<\/a><\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Exp<\/h1>\n\n\n\n<pre class=\"wp-block-code\"><code>from math import gcd\nfrom Crypto.Util.number import inverse, long_to_bytes\n\nn = 60759060882959791909904396677188989949758090199603630243982902422381690538885036721260587316981956179159099537464766520810988299027308891716697721325694989187113132568281096643090555966502943628821584608317087986774067361766441006582461264783625589284748285132591500064467264821214540974749792006934616412217\ncipher = 20458653228553322014465307182393782250675128141639209159045300541287741675246921642347569059959881263633155911063532171465637193709348356233437155581027365642514135793800584667963139842701093152576878356429568990356697857264248093880916698956321511178224500312370845360786231377700287611408999899734512143183\na = 7794809868300816476939749391923181660663599092817735689970830403880360740950291069966802056703842257352942487715953634294627774900178116901736408438781725\nb = 19283995921825875899155714134110227538038032500196406129941198508864582000463560816723795975202107099295086076956040133684\nc = 7794809868300816476939748778965768208814733337627617321244638924271232070361166330324980435743037906985498772947115676315756364476413563742000304770717475\nd = 172332404813056620110912939211150875333966617506319147214329967023854401850532359816888852973202924631133349299841944983684\n\ne = (n - a * a) \/\/ (b * b)\n\nz1 = (a * pow(b, -1, n)) % n\nz2 = (c * pow(d, -1, n)) % n\n\nsum_z = (z1 + z2) % n\n\np = gcd(sum_z, n)\nq = n\/\/p\n\nphi_n = (p - 1) * (q - 1)\nd = inverse(e, phi_n)\n\nm = pow(cipher, d, n)\n\nflag = long_to_bytes(m)\nprint(flag)\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>\u5f88\u6709\u6c34\u5e73\u7684\u4e00\u9053\u9898<\/p>\n","protected":false},"author":3,"featured_media":360,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"class_list":["post-437","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tec"],"_links":{"self":[{"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/posts\/437","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/comments?post=437"}],"version-history":[{"count":1,"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/posts\/437\/revisions"}],"predecessor-version":[{"id":440,"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/posts\/437\/revisions\/440"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/media\/360"}],"wp:attachment":[{"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/media?parent=437"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/categories?post=437"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jotaku.cn\/index.php\/wp-json\/wp\/v2\/tags?post=437"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}