24 lines
1.3 KiB
Plaintext
24 lines
1.3 KiB
Plaintext
The task requires poking machine code directly into memory and executing it. The machine code is the architecture-specific opcodes which have the simple task of adding two unsigned bytes together and making the result available to the high-level language.
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For example, the following assembly language program is given for x86 (32 bit) architectures:
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<syntaxhighlight lang="asm">mov EAX, [ESP+4]
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add EAX, [ESP+8]
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ret</syntaxhighlight>
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This would translate into the following opcode bytes:
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<syntaxhighlight lang="text">139 68 36 4 3 68 36 8 195</syntaxhighlight>
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Or in hexadecimal:
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<syntaxhighlight lang="text">8B 44 24 04 03 44 24 08 C3</syntaxhighlight>
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;Task:
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If different than 32-bit x86, specify the target architecture of the machine code for your example. It may be helpful to also include an assembly version of the machine code for others to reference and understand what is being executed. Then, implement the following in your favorite programming language:
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* Poke the necessary opcodes into a memory location.
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* Provide a means to pass two values to the machine code.
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* Execute the machine code with the following arguments: unsigned-byte argument of value 7; unsigned-byte argument of value 12; The result would be 19.
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* Perform any clean up actions that are appropriate for your chosen language (free the pointer or memory allocations, etc.)
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