mirror of
https://github.com/cea-sec/miasm
synced 2026-06-21 13:48:18 +00:00
Fabrice Desclaux
63 lines
1.5 KiB
Python
63 lines
1.5 KiB
Python
"""
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Parse C expression to access variables and retrieve information:
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* Miasm expression to access this variable
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* variable type
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"""
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from __future__ import print_function
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from miasm.core.ctypesmngr import CTypeStruct, CAstTypes, CTypePtr
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from miasm.arch.x86.ctype import CTypeAMD64_unk
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from miasm.core.objc import CTypesManagerNotPacked, CHandler
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from miasm.expression.expression import ExprId
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"""
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C manipulation example
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"""
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# Digest C information
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text = """
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struct line {
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char color[20];
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int size;
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};
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struct rectangle {
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unsigned int width;
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unsigned int length;
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struct line* line;
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};
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"""
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# Type manager for x86 64: structures not packed
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base_types = CTypeAMD64_unk()
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types_ast = CAstTypes()
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# Add C types definition
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types_ast.add_c_decl(text)
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types_mngr = CTypesManagerNotPacked(types_ast, base_types)
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# Create the ptr variable with type "struct rectangle*"
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ptr_rectangle = types_mngr.get_objc(CTypePtr(CTypeStruct('rectangle')))
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ptr = ExprId('ptr', 64)
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c_context = {ptr.name: ptr_rectangle}
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mychandler = CHandler(types_mngr, C_types=c_context)
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# Parse some C accesses
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c_acceses = ["ptr->width",
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"ptr->length",
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"ptr->line",
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"ptr->line->color",
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"ptr->line->color[3]",
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"ptr->line->size"
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]
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for c_str in c_acceses:
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expr = mychandler.c_to_expr(c_str)
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c_type = mychandler.c_to_type(c_str)
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print('C access:', c_str)
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print('\tExpr:', expr)
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print('\tType:', c_type)
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