2009-03-29 07:30:54 +00:00
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#!/usr/bin/env ruby
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# This file is part of Metasm, the Ruby assembly manipulation suite
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2010-09-09 18:19:35 +00:00
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# Copyright (C) 2006-2009 Yoann GUILLOT
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2009-03-29 07:30:54 +00:00
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#
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# Licence is LGPL, see LICENCE in the top-level directory
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#
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# in this exemple we can write a shellcode using a C function
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#
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require 'metasm'
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# load and decode the file
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sc = Metasm::Shellcode.new(Metasm::Ia32.new)
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sc.parse <<EOS
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jmp c_func
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some_func:
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mov eax, 42
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ret
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EOS
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cp = sc.cpu.new_cparser
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cp.parse <<EOS
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void some_func(void);
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/* __declspec(naked) */ void c_func() {
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int i;
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for (i=0 ; i<10 ; ++i)
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some_func();
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}
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EOS
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asm = sc.cpu.new_ccompiler(cp, sc).compile
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sc.parse asm
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sc.assemble
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sc.encode_file 'shellcode.raw'
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puts Metasm::Shellcode.load_file('shellcode.raw', Metasm::Ia32.new).disassemble
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