from pyvex.block import IRSB
# pylint:disable=attribute-defined-outside-init
[docs]class Lifter:
__slots__ = (
"data",
"bytes_offset",
"opt_level",
"traceflags",
"allow_arch_optimizations",
"strict_block_end",
"collect_data_refs",
"max_inst",
"max_bytes",
"skip_stmts",
"irsb",
"arch",
"addr",
"cross_insn_opt",
"load_from_ro_regions",
)
"""
A lifter is a class of methods for processing a block.
:ivar data: The bytes to lift as either a python string of bytes or a cffi buffer object.
:ivar bytes_offset: The offset into `data` to start lifting at.
:ivar max_bytes: The maximum number of bytes to lift. If set to None, no byte limit is used.
:ivar max_inst: The maximum number of instructions to lift. If set to None, no instruction limit is used.
:ivar opt_level: The level of optimization to apply to the IR, 0-2. Most likely will be ignored in any lifter
other then LibVEX.
:ivar traceflags: The libVEX traceflags, controlling VEX debug prints. Most likely will be ignored in any
lifter other than LibVEX.
:ivar allow_arch_optimizations: Should the LibVEX lifter be allowed to perform lift-time preprocessing
optimizations (e.g., lookback ITSTATE optimization on THUMB)
Most likely will be ignored in any lifter other than LibVEX.
:ivar strict_block_end: Should the LibVEX arm-thumb split block at some instructions, for example CB{N}Z.
:ivar skip_stmts: Should LibVEX ignore statements.
"""
REQUIRE_DATA_C = False
REQUIRE_DATA_PY = False
def __init__(self, arch, addr):
self.arch = arch
self.addr = addr
def _lift(
self,
data,
bytes_offset=None,
max_bytes=None,
max_inst=None,
opt_level=1,
traceflags=None,
allow_arch_optimizations=None,
strict_block_end=None,
skip_stmts=False,
collect_data_refs=False,
cross_insn_opt=True,
load_from_ro_regions=False,
):
"""
Wrapper around the `lift` method on Lifters. Should not be overridden in child classes.
:param data: The bytes to lift as either a python string of bytes or a cffi buffer object.
:param bytes_offset: The offset into `data` to start lifting at.
:param max_bytes: The maximum number of bytes to lift. If set to None, no byte limit is used.
:param max_inst: The maximum number of instructions to lift. If set to None, no instruction limit is
used.
:param opt_level: The level of optimization to apply to the IR, 0-2. Most likely will be ignored in
any lifter other then LibVEX.
:param traceflags: The libVEX traceflags, controlling VEX debug prints. Most likely will be ignored in
any lifter other than LibVEX.
:param allow_arch_optimizations: Should the LibVEX lifter be allowed to perform lift-time preprocessing
optimizations (e.g., lookback ITSTATE optimization on THUMB) Most likely will be
ignored in any lifter other than LibVEX.
:param strict_block_end: Should the LibVEX arm-thumb split block at some instructions, for example CB{N}Z.
:param skip_stmts: Should the lifter skip transferring IRStmts from C to Python.
:param collect_data_refs: Should the LibVEX lifter collect data references in C.
:param cross_insn_opt: If cross-instruction-boundary optimizations are allowed or not.
"""
irsb = IRSB.empty_block(self.arch, self.addr)
self.data = data
self.bytes_offset = bytes_offset
self.opt_level = opt_level
self.traceflags = traceflags
self.allow_arch_optimizations = allow_arch_optimizations
self.strict_block_end = strict_block_end
self.collect_data_refs = collect_data_refs
self.max_inst = max_inst
self.max_bytes = max_bytes
self.skip_stmts = skip_stmts
self.irsb = irsb
self.cross_insn_opt = cross_insn_opt
self.load_from_ro_regions = load_from_ro_regions
self.lift()
return self.irsb
[docs] def lift(self):
"""
Lifts the data using the information passed into _lift. Should be overridden in child classes.
Should set the lifted IRSB to self.irsb.
If a lifter raises a LiftingException on the data, this signals that the lifter cannot lift this data and arch
and the lifter is skipped.
If a lifter can lift any amount of data, it should lift it and return the lifted block with a jumpkind of
Ijk_NoDecode, signalling to pyvex that other lifters should be used on the undecodable data.
"""
raise NotImplementedError()