def make_stdio_sw(fmt_type, types, pointerize):
'''enum -> [str] -> bool -> dict'''
# the printf/scanf parsers can parse nearly all format string types, but we
# do not handle all of them here
fmt_to_type = izip([fmt_type[x] for x in types],
c_type_to_slot)
return {ty: (ep_ct.ptr(val)
if pointerize is True
else val)
for (ty, (_, val)) in fmt_to_type}
def make_stdio_sw(fmt_type, types, pointerize):
'''enum -> [str] -> bool -> dict'''
# the printf/scanf parsers can parse nearly all format string types, but we
# do not handle all of them here
fmt_to_type = izip([fmt_type[x] for x in types],
c_type_to_slot)
return {ty : (ep_ct.ptr(val)
if pointerize is True
else val)
for (ty, (_, val)) in fmt_to_type}
printf_types = [
'TYPE_SCHAR', 'TYPE_UCHAR', 'TYPE_SHORT', 'TYPE_USHORT',
'TYPE_INT', 'TYPE_UINT', 'TYPE_LONGINT', 'TYPE_ULONGINT',
'TYPE_LONGLONGINT', 'TYPE_ULONGLONGINT', 'TYPE_DOUBLE',
'TYPE_DOUBLE', 'TYPE_CHAR'
]
scanf_types = [
'TYPE_SCHAR', 'TYPE_UCHAR', 'TYPE_SHORT', 'TYPE_USHORT',
'TYPE_INT', 'TYPE_UINT', 'TYPE_LONGINT', 'TYPE_ULONGINT',
'TYPE_LONGLONGINT', 'TYPE_ULONGLONGINT', 'TYPE_FLOAT',
'TYPE_DOUBLE', 'TYPE_CHAR'
]
printf_sw = make_stdio_sw(p_Arg_type, printf_types, pointerize=False)
printf_sw[p_Arg_type.TYPE_POINTER] = ep_ct.ptr(ep_ct.simple_typename(['void']))
printf_sw[p_Arg_type.TYPE_STRING] = ep_ct.ptr(ep_ct.simple_typename(['char']))
scanf_sw = make_stdio_sw(s_Arg_type, scanf_types, pointerize=True)
scanf_sw[s_Arg_type.TYPE_POINTER] = ep_ct.ptr(ep_ct.ptr(ep_ct.simple_typename(['void'])))
scanf_sw[s_Arg_type.TYPE_STRING] = ep_ct.ptr(ep_ct.simple_typename(['char']))
scanf_sw[s_Arg_type.TYPE_CHARSEQ] = scanf_sw[s_Arg_type.TYPE_STRING]
def n32ify_regs(regs):
'''[str] -> [str]'''
n32_map = {'$t0': '$a4', '$t1': '$a5', '$t2': '$a6', '$t3': '$a7'}
r = enumerate(regs)
return list(n32_map[reg] if reg in n32_map else regs[i] for (i, reg) in r)
def fmt_op(arg, mnem, op=None):
'''op_ty -> str -> opt:int -> c_ast()'''
insn = insns.insns[mnem]
def addrof_or_deref(arg):
# since addiu cannot touch memory, it must be calculating an address
if mnem == 'addiu' or (insn.ty == insns.types.usefn and insn.subst == 'memcpy'):
return c_ast.UnaryOp('&', arg)
else:
return arg
if arg.ty == ida.op_ty.reg:
try:
slot = insn.slots[op]
except IndexError:
slot = None
reg = fmt_reg(mnem, arg.val, slot)
if insn.ty == insns.types.usefn and insn.subst == 'memcpy':
return c_ast.UnaryOp('&', reg)
else:
return reg
if mnem == 'la':
# XXX the "name" type is neither suitable for a decompiler nor a
# braindead static translator such as this one. i.e., in order to
# translate to C, we have no choice but to deal with C's type system,
# because things like "la ptr" should be translated as "reg = ptr", but
# "la not_ptr" should be translated as "reg = ¬_ptr"
if arg.ty in [ida.op_ty.array, ida.op_ty.ptr]:
return c_ast.ID(arg.val)
elif arg.ty == ida.op_ty.name:
return c_ast.UnaryOp('&', c_ast.ID(arg.val))
else: # an address
return c_ast.Constant('int', str(arg.val))
elif arg.ty == ida.op_ty.array:
(idx, rem) = ida.item_off(arg.target)
arr = c_ast.ArrayRef(c_ast.ID(arg.val), c_ast.Constant('int', str(idx)))
return addrof_or_deref(arr)
# retained in case we ever come across some strange pointer math. this
# will generate a nonsense lvalue anyway, so we'd need to handle it some
# other way
# left = addrof_or_deref(arr)
#return c_ast.BinaryOp('+', left, c_ast.Constant('int', str(rem)))
elif arg.ty == ida.op_ty.ptr:
# dereferencing of pointers is handled by the "displ" case, so just
# return an address here too
(_, rem) = ida.item_off(arg.target)
return c_ast.ID(arg.val)
# same as above
# return c_ast.BinaryOp('+',
# c_ast.ID(arg.val),
# c_ast.Constant('int', str(rem)))
elif arg.ty == ida.op_ty.name:
nameval = c_ast.ID(arg.val)
return addrof_or_deref(nameval)
elif arg.ty == ida.op_ty.displ:
r = fmt_reg(mnem, arg.val.reg, ep_ct.slot_types.u32)
off = c_ast.BinaryOp('+', r, c_ast.Constant('int', str(arg.val.displ)))
tyns = ['char' if insns.types.usefn and insn.subst == 'memcpy'
else insn.subst]
cast = ep_ct.simple_cast(ep_ct.ptr(ep_ct.simple_typename(tyns)), off)
if insn.ty == insns.types.usefn and insn.subst == 'memcpy':
return cast
else:
return c_ast.UnaryOp('*', cast)
else:
return c_ast.Constant('int', str(arg.val))
printf_types = [
'TYPE_SCHAR', 'TYPE_UCHAR', 'TYPE_SHORT', 'TYPE_USHORT',
'TYPE_INT', 'TYPE_UINT', 'TYPE_LONGINT', 'TYPE_ULONGINT',
'TYPE_LONGLONGINT', 'TYPE_ULONGLONGINT', 'TYPE_DOUBLE',
'TYPE_DOUBLE', 'TYPE_CHAR'
]
scanf_types = [
'TYPE_SCHAR', 'TYPE_UCHAR', 'TYPE_SHORT', 'TYPE_USHORT',
'TYPE_INT', 'TYPE_UINT', 'TYPE_LONGINT', 'TYPE_ULONGINT',
'TYPE_LONGLONGINT', 'TYPE_ULONGLONGINT', 'TYPE_FLOAT',
'TYPE_DOUBLE', 'TYPE_CHAR'
]
printf_sw = make_stdio_sw(p_Arg_type, printf_types, pointerize=False)
printf_sw[p_Arg_type.TYPE_POINTER] = ep_ct.ptr(
ep_ct.simple_typename(['void']))
printf_sw[p_Arg_type.TYPE_STRING] = ep_ct.ptr(
ep_ct.simple_typename(['char']))
scanf_sw = make_stdio_sw(s_Arg_type, scanf_types, pointerize=True)
scanf_sw[s_Arg_type.TYPE_POINTER] = ep_ct.ptr(ep_ct.ptr(
ep_ct.simple_typename(['void'])))
scanf_sw[s_Arg_type.TYPE_STRING] = ep_ct.ptr(
ep_ct.simple_typename(['char']))
scanf_sw[s_Arg_type.TYPE_CHARSEQ] = scanf_sw[s_Arg_type.TYPE_STRING]
def n32ify_regs(regs):
'''[str] -> [str]'''
n32_map = {'$t0' : '$a4', '$t1' : '$a5', '$t2' : '$a6', '$t3' : '$a7'}
r = enumerate(regs)