{"id":1395,"date":"2024-04-09T15:26:24","date_gmt":"2024-04-09T07:26:24","guid":{"rendered":"https:\/\/www.yizishun.com\/?p=1395"},"modified":"2024-04-09T20:34:14","modified_gmt":"2024-04-09T12:34:14","slug":"glibc-dynamic-link%e7%9b%b8%e5%85%b3%e6%ba%90%e7%a0%81%e9%98%85%e8%af%bb","status":"publish","type":"post","link":"https:\/\/www.yizishun.com\/?p=1395","title":{"rendered":"glibc dynamic-link\u5b66\u4e60\uff08give up\u7248\uff09"},"content":{"rendered":"\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-vivid-green-cyan-color\">\u52a8\u673a<\/mark><\/strong>\uff1a\u56e0\u4e3a\u4e00\u4e2a\u9ad8\u4e2d\u751fCTF\u6709\u8fd140%\u7684pwn\u9898\u662f\u5173\u4e8e\u52a8\u6001\u94fe\u63a5\u548cELF\u6587\u4ef6\u683c\u5f0f\u7684\u4fee\u6539\u7684\uff0c\u867d\u7136\u6211\u4e00\u9053\u9898\u90fd\u6ca1\u6709\u5199\u51fa\u6765\uff08\u501f\u53e3\u662f\u4ece\u6ca1\u505a\u8fc7\u8fd9\u7c7b\u9898\ud83d\ude2c\ud83d\ude2c\uff09\uff0c\u4f46\u662f\u5728\u89e3\u9898\u7684\u8fc7\u7a0b\u4e2d\u6211\u5374\u6536\u83b7\u4e86\u5f88\u591a\u539f\u6765\u4e0d\u77e5\u9053\u7684\u77e5\u8bc6\uff0c\u56e0\u6b64\u4ea7\u751f\u4e86RTFSC\u4e00\u63a2\u7a76\u7adf\u7684\u60f3\u6cd5<\/p>\n\n\n\n<p>\u5199\u7684\u65f6\u5019\u770b\u5230\u4e86\u4e00\u7bc7\u4e0d\u9519\u7684\u535a\u5ba2\uff1a<a href=\"https:\/\/www.cnblogs.com\/linhaostudy\/p\/10544917.html\">\u52a8\u6001\u94fe\u63a5\u7684\u6b65\u9aa4\u4e0e\u5b9e\u73b0 &#8211; yooooooo &#8211; \u535a\u5ba2\u56ed (cnblogs.com<\/a> \u6211\u53d1\u73b0\u8fd9\u4e2a\u535a\u5ba2\u771f\u7684\u662f\u6df1\u5165\u6d45\u51fa\uff0c\u6b63\u60f3\u7740\u600e\u4e48\u6709\u8fd9\u4e48\u597d\u7684\u4e00\u7bc7\u535a\u5ba2\uff0c\u770b\u5230\u4e86\u4e00\u4e2a\u201c\u672c\u4e66\u201d\uff0c\u8fd9\u4e2a\u597d\u50cf\u5c31\u662f\u6211\u4e0a\u5b66\u671f\u5b66\u4e60\u52a8\u6001\u94fe\u63a5\u770b\u7684\u4e00\u672c\u4e66\uff0c\u300a\u7a0b\u5e8f\u5458\u7684\u81ea\u6211\u4fee\u517b\u300b\uff0c\u54ce\uff0c\u679c\u7136\u4e0d\u540c\u7684\u65f6\u5019\u770b\u6709\u5b8c\u5168\u4e0d\u4e00\u6837\u7684\u611f\u89c9<\/p>\n\n\n\n<p>\u7533\u660e\uff0c\u8fd9\u4e00\u90e8\u5206\u5f88\u591a\u6211\u90fd\u662f\u62f7\u95eeGPT\u548c\u81ea\u5df1\u731c\u7684\uff0c\u4e0d\u4fdd\u8bc1\u5b8c\u5168\u662f\u8fd9\u6837\u554a<\/p>\n\n\n\n<p>\u8bf7\u8bfb\u8005\uff08\u548c\u4ee5\u540e\u590d\u4e60\u7684\u6211\uff09\u5148\u968f\u6211\u8fdb\u5165glibc\u7684\u6df1\u5904\uff0c\u4ece\u4e00\u6761syscall\u5f00\u59cb\u51fa\u53d1\uff0c\u5148\u4ece\u64cd\u4f5c\u7cfb\u7edf\u7684\u89c6\u89d2\u6765\u770b\u52a8\u6001\u94fe\u63a5\u5668\uff08\u5185\u6838\u6001\uff09\uff0c\u4e4b\u540e\u6211\u4f1a\u5c06\u89c6\u89d2\u62c9\u5230\u52a8\u6001\u94fe\u63a5\u5668\u4e0a\u9762\uff08\u6211\u79f0\u4e4b\u4e3a\u4f2a\u5185\u6838\u6001\u563f\u563f\uff09\uff0c\u518d\u4e4b\u540e\u6211\u4f1a\u5c06\u89c6\u89d2\u62c9\u5230\u666e\u901a\u7a0b\u5e8f\u4e0a\u9762\uff08\u7528\u6237\u6001\uff09\uff0c\u6700\u540e\u89c6\u89d2\u5c06\u662f\u7528\u6237\u7a0b\u5e8ftrap into\u52a8\u6001\u94fe\u63a5\u5668\uff08syscall\u90e8\u5206\u7684\u539f\u7406\u662f\u6211\u7684\u731c\u6d4b\uff08\u5408\u7406\u63a8\u6d4b\uff09\uff09<\/p>\n\n\n\n<p>\u8fd9\u662f\u8fd9\u6761syscall\u7684\u539f\u578b\uff1a<\/p>\n\n\n\n<p>int <strong>execve<\/strong>(const char *path, char *const argv[], char *const envp[]);<\/p>\n\n\n\n<p>os\u63a5\u6536\u5230\u8fd9\u6837\u4e00\u6761syscall\u65f6\uff0c\u4f1a\u8c03\u7528\u5185\u90e8\u7684loader\uff08\u52a0\u8f7d\u5668\uff09\uff0c\u8fd9\u4e2a\u52a0\u8f7d\u5668\u4f1a\u5c06\u8fd9\u4e2aELF\u6587\u4ef6\u6307\u793a\u7684\u90e8\u5206\u52a0\u8f7d\u5230\u5185\u5b58\u4e2d\uff0c\u52a0\u8f7d\u5668\u770b\u7684\u662fELF\u6587\u4ef6\u4e2d\u7684phdr\u7684\u90e8\u5206\uff0c\u4ed6\u5c06ELF\u6587\u4ef6\u4e2dphdr\u6307\u793a\u7684\u7c7b\u578b\u4e3aPT_LOAD\u7684\u6761\u76ee\u6309\u7167\u6307\u793a\u7684\u6743\u9650\uff0c\u5927\u5c0f\uff0c\u88ab\u52a0\u8f7d\u8fdb\u53bb\u7684\u865a\u62df\u5185\u5b58\u5730\u5740\u52a0\u8f7d\u5230\u6307\u5b9a\u7684\u4f4d\u7f6e\uff08\u8fd9\u91cc\u63d2\u4e00\u53e5\uff0c\u5982\u679c\u662f\u4eba\u6765\u770breadelf -a\u7684\u8bdd\u4e0d\u8981\u53bb\u770bphdr\uff0c\u53bb\u770bshdr\uff0csection\u6bd4segment\u5206\u7684\u66f4\u7ec6\uff0c\u5e76\u4e14\u975e\u5e38\u6e05\u6670\uff0c\u987a\u5e8f\u57fa\u672c\u4e0a\u4e5f\u5c31\u662f\u52a0\u8f7d\u8fdb\u5185\u5b58\u7684\u987a\u5e8f\uff0c\u4e5f\u6709\u6743\u9650\u63cf\u8ff0\u5565\u7684\uff0c\u4f60\u53ef\u4ee5\u5728shdr\u4e2d\u770b\u5230\u4e00\u4e9b\u6709\u8da3\u7684\u73b0\u8c61\uff0c\u6bd4\u5982symtab\u548cstrtab\u6ca1\u6709\u52a0\u8f7d\u8fdb\u5185\u5b58\u4e2d\uff0c\u4f46\u662fdynsym\u548cdynstr\u90fd\u88ab\u52a0\u8f7d\u8fdb\u53bb\u4e86\uff09\uff0cloader\u9664\u4e86\u52a0\u8f7dELF loader\u6240\u6307\u793a\u7684\u90e8\u5206\uff0c\u4ed6\u8fd8\u4f1a\u770bphdr\u7684INTERP segment\uff0c\u8fd9\u4e2asegment\u6307\u793a\u4e86\u52a8\u6001\u94fe\u63a5\u5668\u7684\u8def\u5f84\uff0c\u4e8e\u662fos\u7684loader\u5c31\u4f1a\u6839\u636e\u64cd\u4f5c\u7cfb\u7edf\u7684\u7b56\u7565\u6765\u51b3\u5b9a\u6765\u5c06ld\u52a0\u8f7d\u5230\u54ea\u91cc\uff08\u5176\u5b9eld.so\u4e5f\u4e0d\u8fc7\u5c31\u662f\u4e00\u4e2aELF\u6587\u4ef6\uff0c\u5e76\u4e14\u8fd9\u4e2a\u6587\u4ef6\u4e5f\u662f\u4e00\u4e2a\u9700\u8981\u52a8\u6001\u94fe\u63a5\u7684\u7a0b\u5e8f\uff0c\u6211\u4e5f\u662f\u5199\u8fd9\u4e9b\u6587\u5b57\u7684\u65f6\u5019\u7a81\u7136\u60f3\u5230\uff0c\u8fd9\u7279\u522b\u50cf\u4e16\u754c\u7b2c\u4e00\u4e2a\u6b3e\u7f16\u8bd1\u5668\u662f\u88ab\u600e\u4e48\u7f16\u8bd1\u7684\u8fd9\u4e2a\u95ee\u9898\uff0c\u6240\u4ee5\u8bf4\u8fd9\u4e2a\u52a8\u6001\u94fe\u63a5\u5668\u80af\u5b9a\u9700\u8981\u548c\u4e00\u822c\u7684ELF\u6587\u4ef6\u4e0d\u540c\uff0c\u4ed6\u901a\u8fc7\u201c\u81ea\u4e3e\u201d\u7684\u65b9\u5f0f\u6765\u5bf9\u81ea\u5df1\u8fdb\u884c\u52a8\u6001\u94fe\u63a5\uff0c\u8fd9\u4e2a\u4e4b\u540e\u5e94\u8be5\u4f1a\u5728\u6e90\u7801\u4e2d\u6709\u6240\u4f53\u73b0\uff09\uff0c\u4e4b\u540eos\u6839\u636e\u52a8\u6001\u94fe\u63a5\u5668\u4e2d\u7684ehdr\u7684e_entry\u6765\u8bbe\u7f6epc\uff0c\u7531\u52a8\u6001\u94fe\u63a5\u5668\u63a5\u7ba1<\/p>\n\n\n\n<p>\u5230\u6b64\u5c31\u662f\u52a8\u6001\u94fe\u63a5\u5668\u5728\u8fdb\u7a0b\u4e2d\u7684\u201c\u8bde\u751f\u201d\u8fc7\u7a0b\u4e86\uff08pc = \u52a8\u6001\u94fe\u63a5\u5668\u7684_start\uff09\uff0c\u73b0\u5728\u5c06\u89c6\u89d2\u62c9\u5230\u52a8\u6001\u94fe\u63a5\u5668\u4e0a\u9762<\/p>\n\n\n\n<p>ok\uff0c\u5f00\u59cb\u770b\u6e90\u7801\u5427<\/p>\n\n\n\n<p>\u5148\u5728glibc\u4e2d\u627e\u5230_start\u51fd\u6570\u7684\u7b26\u53f7\uff0c\u53d1\u73b0\u4ed6\u4e00\u5f00\u59cb\u8c03\u7528\u4e86_dl_start\u51fd\u6570&#8230;&#8230;<\/p>\n\n\n\n<p>give up\u4e86\uff0c\u653e\u5f03\u4e86\uff0c\u6211\u539f\u672c\u4ee5\u4e3a\u4e0d\u96be\u7684\uff0c\u8fd8\u662f\u773c\u9ad8\u624b\u4f4e\u4e86\u54ce\uff0c\u53ef\u662f\u8fd9\u5176\u5b9e\u662flibc\u7684\u542f\u52a8\u4ee3\u7801\uff0c\u6bd4\u6211\u4e4b\u524d\u770b\u7684malloc\u4ec0\u4e48\u7684\u6e90\u7801\u8fd8\u96be\u7684\u591a\uff0c\u6211\u89c9\u5f97\u90a3\u672c\u4e66\u4e2d\u6709\u6bb5\u8bdd\u8bf4\u5230\u6211\u5fc3\u91cc\u53bb\u4e86\uff1a<\/p>\n\n\n\n<p>\u201c\u6e90\u4ee3\u7801\u5728\u7ecf\u8fc7\u591a\u5e74\u7684\u53d1\u5c55\u548c\u9524\u70bc\u540e\uff0c\u53d8\u5f97\u975e\u5e38\u6ce8\u91cd\u6027\u80fd\u548c\u6548\u7387\uff0c\u800c\u5f88\u5c11\u8003\u8651\u53ef\u8bfb\u6027\uff0c\u8fd9\u4f7f\u5f97\u901a\u8fc7\u6316\u6398\u6e90\u4ee3\u7801\u7406\u89e3\u673a\u5236\u53d8\u5f97\u66f4\u4e3a\u56f0\u96be\u201d<\/p>\n\n\n\n<p>\u6700\u4e3b\u8981\u7684\u662fmalloc\uff0cprintf\u8fd9\u4e9b\u51fd\u6570\u7684\u884c\u4e3a\u6211\u592a\u6e05\u695a\u4e86\uff0c\u539f\u7406\u6e05\u695a\u90a3\u81ea\u7136\u770b\u4ee3\u7801\u4e0d\u96be\u4e86\uff0c\u4f46\u662f\u8fd9\u4e2a\u542f\u52a8\u7684\u539f\u7406\u6211\u5c31\u6709\u70b9\u641e\u4e0d\u660e\u767d\uff0c\u4f46\u662f\u6211\u53d1\u73b0\u4e86\u624b\u518c\u4e0a\u4f3c\u4e4e\u6e05\u695a\u7684\u5b9a\u4e49\u4e86libc\u542f\u52a8\u7684\u8be6\u7ec6\u8fc7\u7a0b<\/p>\n\n\n\n<p><a href=\"https:\/\/www.gnu.org\/software\/hurd\/glibc\/startup.html\">startup (gnu.org)<\/a>\uff08\u8fd9\u4e2a\u624b\u518c\u4f3c\u4e4e\u63cf\u8ff0\u7684\u4e0d\u662flinux\u5185\u6838\u7684\uff09<br><a href=\"https:\/\/sourceware.org\/glibc\/wiki\/DynamicLoader\">DynamicLoader &#8211; glibc wiki (sourceware.org)<\/a>\uff08ftrace\uff09<\/p>\n\n\n\n<p>\u8fd8\u662f\u624b\u518c\u7ba1\u7528\uff0c\u76f4\u63a5\u628a\u6211\u60f3\u8981\u4e86\u89e3\u7684\u5168\u90e8\u5199\u7684\u6e05\u6e05\u695a\u695a\uff0c\u4e0d\u7981\u53cd\u601d\uff0c\u4e3a\u4ec0\u4e48\u6211\u4e4b\u524d\u60f3\u8981\u4e86\u89e3\u4e00\u4e2a\u7a0b\u5e8f\u7684\u884c\u4e3a\u7b2c\u4e00\u53cd\u5e94\u662f\u76f4\u63a5RTFSC\u800c\u4e0d\u662fRTFM\uff0c\u8fd9\u4e0b\u78b0\u58c1\u4e86\u5427\uff0c\u4e0d\u8fc7\u8fd9\u6837\u6211\u4e5f\u8bb0\u5fc6\u6df1\u523b\uff0c\u6bcf\u5f53\u60f3RTFSC\u7684\u65f6\u5019\u60f3\u4e00\u60f3\u6211\u6709\u6ca1\u6709\u5148\u597d\u597d\u8bfb\u624b\u518c\u3002<\/p>\n\n\n\n<p>\u4f3c\u4e4e\u4e3b\u8981\u7684\u51fd\u6570\u662fdl_main\uff0c\u4f46\u662f\u6211\u8fd8\u6ca1\u770b\u5230\u90a3\u5c31\u653e\u5f03\u4e86&#8230;&#8230;(\u8d85\uff0c\u597d\u70e6\uff0c\u6211\u89c9\u5f97\u6211\u8fd8\u662f\u6709\u5fc5\u8981\u770b\u4e00\u4e0bdl_main\u8fd9\u4e2a\u51fd\u6570\u7684\uff0c\u4f46\u662f\u4ed6\u67091000\u884c\u554a\uff0c\u4e4b\u540e\u6709\u65f6\u95f4\u518d\u770b\u5427)<\/p>\n\n\n\n<p>\u4e22\u51e0\u4e2a\u94fe\u63a5<\/p>\n\n\n\n<p><a href=\"https:\/\/blog.csdn.net\/conansonic\/article\/details\/63254223\">_dl_start_user\u6e90\u7801\u5206\u6790\uff08\u4e00\uff09-CSDN\u535a\u5ba2<\/a><\/p>\n\n\n\n<p>\u6211\u5728\u4e0a\u5b66\u671f\u521a\u5b66pwn\u7684\u65f6\u5019\u5c31\u770b\u4e86\u300a\u7a0b\u5e8f\u5458\u7684\u81ea\u6211\u4fee\u517b\u300b\u90a3\u672c\u4e66\uff0c\u548c\u6211\u73b0\u5728\u770b\u7684\u611f\u89c9\u5b8c\u5168\u4e0d\u540c\uff0c\u6211\u6253\u7b97\u597d\u597d\u7422\u78e8\u4e00\u4e0b\u8fd9\u672c\u4e66\ud83d\udcaa\ud83d\udcaa<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u52a8\u673a\uff1a\u56e0\u4e3a\u4e00\u4e2a\u9ad8\u4e2d\u751fCTF\u6709\u8fd140%\u7684pwn\u9898\u662f\u5173\u4e8e\u52a8\u6001\u94fe\u63a5&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[18,48,35],"tags":[33,49],"class_list":["post-1395","post","type-post","status-publish","format-standard","hentry","category-ctf","category-libc","category-pwn","tag-pwn","tag-rtfsc"],"_links":{"self":[{"href":"https:\/\/www.yizishun.com\/index.php?rest_route=\/wp\/v2\/posts\/1395","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.yizishun.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.yizishun.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.yizishun.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.yizishun.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1395"}],"version-history":[{"count":21,"href":"https:\/\/www.yizishun.com\/index.php?rest_route=\/wp\/v2\/posts\/1395\/revisions"}],"predecessor-version":[{"id":1425,"href":"https:\/\/www.yizishun.com\/index.php?rest_route=\/wp\/v2\/posts\/1395\/revisions\/1425"}],"wp:attachment":[{"href":"https:\/\/www.yizishun.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1395"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.yizishun.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1395"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.yizishun.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1395"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}