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import logging
from argparse import ArgumentParser
from pdb import pm
from miasm2.analysis.binary import Container
from miasm2.core.asmblock import log_asmblock, AsmCFG
from miasm2.core.interval import interval
from miasm2.analysis.machine import Machine
from miasm2.analysis.data_flow import dead_simp, DiGraphDefUse, \
ReachingDefinitions, merge_blocks, remove_empty_assignblks, \
PropagateExpr, replace_stack_vars, load_from_int, \
del_unused_edges
from miasm2.expression.simplifications import expr_simp
from miasm2.analysis.ssa import SSADiGraph
from miasm2.analysis.outofssa import UnSSADiGraph
from miasm2.analysis.data_flow import DiGraphLivenessSSA
from miasm2.ir.ir import AssignBlock, IRBlock
log = logging.getLogger("dis")
console_handler = logging.StreamHandler()
console_handler.setFormatter(logging.Formatter("%(levelname)-5s: %(message)s"))
log.addHandler(console_handler)
log.setLevel(logging.INFO)
parser = ArgumentParser("Disassemble a binary")
parser.add_argument('filename', help="File to disassemble")
parser.add_argument('address', help="Starting address for disassembly engine",
nargs="*")
parser.add_argument('-m', '--architecture', help="architecture: " + \
",".join(Machine.available_machine()))
parser.add_argument('-f', "--followcall", action="store_true",
help="Follow call instructions")
parser.add_argument('-b', "--blockwatchdog", default=None, type=int,
help="Maximum number of basic block to disassemble")
parser.add_argument('-n', "--funcswatchdog", default=None, type=int,
help="Maximum number of function to disassemble")
parser.add_argument('-r', "--recurfunctions", action="store_true",
help="Disassemble founded functions")
parser.add_argument('-v', "--verbose", action="count", help="Verbose mode")
parser.add_argument('-g', "--gen_ir", action="store_true",
help="Compute the intermediate representation")
parser.add_argument('-z', "--dis-nulstart-block", action="store_true",
help="Do not disassemble NULL starting block")
parser.add_argument('-l', "--dontdis-retcall", action="store_true",
help="If set, disassemble only call destinations")
parser.add_argument('-s', "--simplify", action="count",
help="Apply simplifications rules (liveness, graph simplification, ...)")
parser.add_argument("--base-address", default=0,
type=lambda x: int(x, 0),
help="Base address of the input binary")
parser.add_argument('-a', "--try-disasm-all", action="store_true",
help="Try to disassemble the whole binary")
parser.add_argument('-i', "--image", action="store_true",
help="Display image representation of disasm")
parser.add_argument('-c', "--rawbinary", default=False, action="store_true",
help="Don't interpret input as ELF/PE/...")
parser.add_argument('-d', "--defuse", action="store_true",
help="Dump the def-use graph in file 'defuse.dot'."
"The defuse is dumped after simplifications if -s option is specified")
parser.add_argument('-p', "--ssa", action="store_true",
help="Generate the ssa form in 'ssa.dot'.")
parser.add_argument('-x', "--propagexpr", action="store_true",
help="Do Expression propagation.")
parser.add_argument('-y', "--stack2var", action="store_true",
help="*Try* to do transform stack accesses into variables. "
"Use only with --propagexpr option. "
"WARNING: not reliable, may fail.")
parser.add_argument('-e', "--loadint", action="store_true",
help="Load integers from binary in fixed memory lookup.")
parser.add_argument('-j', "--calldontmodstack", action="store_true",
help="Consider stack high is not modified in subcalls")
args = parser.parse_args()
if args.verbose:
log_asmblock.setLevel(logging.DEBUG)
log.info('Load binary')
if args.rawbinary:
cont = Container.fallback_container(open(args.filename, "rb").read(),
vm=None, addr=args.base_address)
else:
with open(args.filename, "rb") as fdesc:
cont = Container.from_stream(fdesc, addr=args.base_address)
default_addr = cont.entry_point
bs = cont.bin_stream
e = cont.executable
log.info('ok')
log.info("import machine...")
# Use the guessed architecture or the specified one
arch = args.architecture if args.architecture else cont.arch
if not arch:
print "Architecture recognition fail. Please specify it in arguments"
exit(-1)
# Instance the arch-dependent machine
machine = Machine(arch)
mn, dis_engine = machine.mn, machine.dis_engine
ira, ir = machine.ira, machine.ir
log.info('ok')
mdis = dis_engine(bs, loc_db=cont.loc_db)
# configure disasm engine
mdis.dontdis_retcall = args.dontdis_retcall
mdis.blocs_wd = args.blockwatchdog
mdis.dont_dis_nulstart_bloc = not args.dis_nulstart_block
mdis.follow_call = args.followcall
todo = []
addrs = []
for addr in args.address:
try:
addrs.append(int(addr, 0))
except ValueError:
# Second chance, try with symbol
loc_key = mdis.loc_db.get_name_location(addr)
offset = mdis.loc_db.get_location_offset(loc_key)
addrs.append(offset)
if len(addrs) == 0 and default_addr is not None:
addrs.append(default_addr)
for ad in addrs:
todo += [(mdis, None, ad)]
done = set()
all_funcs = set()
all_funcs_blocks = {}
done_interval = interval()
finish = False
entry_points = set()
# Main disasm loop
while not finish and todo:
while not finish and todo:
mdis, caller, ad = todo.pop(0)
if ad in done:
continue
done.add(ad)
asmcfg = mdis.dis_multiblock(ad)
entry_points.add(mdis.loc_db.get_offset_location(ad))
log.info('func ok %.16x (%d)' % (ad, len(all_funcs)))
all_funcs.add(ad)
all_funcs_blocks[ad] = asmcfg
for block in asmcfg.blocks:
for l in block.lines:
done_interval += interval([(l.offset, l.offset + l.l)])
if args.funcswatchdog is not None:
args.funcswatchdog -= 1
if args.recurfunctions:
for block in asmcfg.blocks:
instr = block.get_subcall_instr()
if not instr:
continue
for dest in instr.getdstflow(mdis.loc_db):
if not dest.is_loc():
continue
offset = mdis.loc_db.get_location_offset(dest.loc_key)
todo.append((mdis, instr, offset))
if args.funcswatchdog is not None and args.funcswatchdog <= 0:
finish = True
if args.try_disasm_all:
for a, b in done_interval.intervals:
if b in done:
continue
log.debug('add func %s' % hex(b))
todo.append((mdis, None, b))
# Generate dotty graph
all_asmcfg = AsmCFG(mdis.loc_db)
for blocks in all_funcs_blocks.values():
all_asmcfg += blocks
log.info('generate graph file')
open('graph_execflow.dot', 'w').write(all_asmcfg.dot(offset=True))
log.info('generate intervals')
all_lines = []
total_l = 0
print done_interval
if args.image:
log.info('build img')
done_interval.show()
for i, j in done_interval.intervals:
log.debug((hex(i), "->", hex(j)))
all_lines.sort(key=lambda x: x.offset)
open('lines.dot', 'w').write('\n'.join([str(l) for l in all_lines]))
log.info('total lines %s' % total_l)
if args.propagexpr:
args.gen_ir = True
class IRADelModCallStack(ira):
def call_effects(self, addr, instr):
assignblks, extra = super(IRADelModCallStack, self).call_effects(addr, instr)
if not args.calldontmodstack:
return assignblks, extra
out = []
for assignblk in assignblks:
dct = dict(assignblk)
dct = {
dst:src for (dst, src) in dct.iteritems() if dst != self.sp
}
out.append(AssignBlock(dct, assignblk.instr))
return out, extra
# Bonus, generate IR graph
if args.gen_ir:
log.info("generating IR and IR analysis")
ir_arch = ir(mdis.loc_db)
ir_arch_a = IRADelModCallStack(mdis.loc_db)
ircfg = ir_arch.new_ircfg()
ircfg_a = ir_arch.new_ircfg()
ir_arch.blocks = {}
ir_arch_a.blocks = {}
for ad, asmcfg in all_funcs_blocks.items():
log.info("generating IR... %x" % ad)
for block in asmcfg.blocks:
ir_arch.add_asmblock_to_ircfg(block, ircfg)
ir_arch_a.add_asmblock_to_ircfg(block, ircfg_a)
log.info("Print blocks (without analyse)")
for label, block in ir_arch.blocks.iteritems():
print block
log.info("Gen Graph... %x" % ad)
log.info("Print blocks (with analyse)")
for label, block in ir_arch_a.blocks.iteritems():
print block
if args.simplify > 0:
log.info("dead simp...")
dead_simp(ir_arch_a, ircfg_a)
log.info("ok...")
if args.defuse:
reachings = ReachingDefinitions(ircfg_a)
open('graph_defuse.dot', 'w').write(DiGraphDefUse(reachings).dot())
out = ircfg.dot()
open('graph_irflow_raw.dot', 'w').write(out)
out = ircfg_a.dot()
open('graph_irflow.dot', 'w').write(out)
if args.simplify > 1:
ircfg_a.simplify(expr_simp)
modified = True
while modified:
modified = False
modified |= dead_simp(ir_arch_a, ircfg_a)
modified |= remove_empty_assignblks(ircfg_a)
open('graph_irflow_reduced.dot', 'w').write(ircfg_a.dot())
if args.ssa and not args.propagexpr:
if len(entry_points) != 1:
raise RuntimeError("Your graph should have only one head")
head = list(entry_points)[0]
ssa = SSADiGraph(ircfg_a)
ssa.transform(head)
open("ssa.dot", "wb").write(ircfg_a.dot())
if args.propagexpr:
class IRAOutRegs(ira):
def get_out_regs(self, block):
regs_todo = super(self.__class__, self).get_out_regs(block)
out = {}
for assignblk in block:
for dst in assignblk:
reg = self.ssa_var.get(dst, None)
if reg is None:
continue
if reg in regs_todo:
out[reg] = dst
return set(out.values())
# Add dummy dependency to uncover out regs assignment
for loc in ircfg_a.leaves():
irblock = ircfg_a.blocks.get(loc)
if irblock is None:
continue
regs = {}
for reg in ir_arch_a.get_out_regs(irblock):
regs[reg] = reg
assignblks = list(irblock)
new_assiblk = AssignBlock(regs, assignblks[-1].instr)
assignblks.append(new_assiblk)
new_irblock = IRBlock(irblock.loc_key, assignblks)
ircfg_a.blocks[loc] = new_irblock
ir_arch_a = IRAOutRegs(mdis.loc_db)
def is_addr_ro_variable(bs, addr, size):
"""
Return True if address at @addr is a read-only variable.
WARNING: Quick & Dirty
@addr: integer representing the address of the variable
@size: size in bits
"""
try:
_ = bs.getbytes(addr, size/8)
except IOError:
return False
return True
ir_arch_a.ssa_var = {}
index = 0
modified = True
ssa_forbidden_regs = set([
ir_arch_a.pc,
ir_arch_a.IRDst,
ir_arch_a.arch.regs.exception_flags
])
head = list(entry_points)[0]
heads = set([head])
all_ssa_vars = {}
propagate_expr = PropagateExpr()
ssa_variable_to_expr = {}
while modified:
ssa = SSADiGraph(ircfg_a)
ssa.immutable_ids.update(ssa_forbidden_regs)
ssa.ssa_variable_to_expr.update(all_ssa_vars)
ssa.transform(head)
all_ssa_vars.update(ssa.ssa_variable_to_expr)
if args.verbose > 3:
open("ssa_%d.dot" % index, "wb").write(ircfg_a.dot())
ir_arch_a.ssa_var.update(ssa.ssa_variable_to_expr)
if args.verbose > 3:
open("ssa_orig.dot", "wb").write(ircfg_a.dot())
while modified:
log.debug('Loop %d', index)
index += 1
modified = False
if args.verbose > 3:
open('tmp_before_%d.dot' % index, 'w').write(ircfg_a.dot())
modified |= propagate_expr.propagate(ssa, head)
if args.verbose > 3:
open('tmp_adter_%d.dot' % index, 'w').write(ircfg_a.dot())
modified |= ircfg_a.simplify(expr_simp)
if args.verbose > 3:
open('tmp_simp_%d.dot' % index, 'w').write(ircfg_a.dot())
simp_modified = True
while simp_modified:
index += 1
if args.verbose > 3:
open('tmp_before_%d.dot' % index, 'w').write(ircfg_a.dot())
simp_modified = False
log.info("dead simp...")
simp_modified |= dead_simp(ir_arch_a, ircfg_a)
log.info("ok...")
index += 1
if args.verbose > 3:
open('tmp_after_%d.dot' % index, 'w').write(ircfg_a.dot())
simp_modified |= remove_empty_assignblks(ircfg_a)
simp_modified |= del_unused_edges(ircfg_a, heads)
simp_modified |= merge_blocks(ircfg_a, heads)
if args.loadint:
simp_modified |= load_from_int(ircfg_a, bs, is_addr_ro_variable)
modified |= simp_modified
index += 1
if args.verbose > 3:
open('stack_%d.dot' % index, 'w').write(ircfg_a.dot())
if args.stack2var:
modified |= replace_stack_vars(ir_arch_a, ssa)
if args.verbose > 3:
open('final_pre.dot', 'w').write(ircfg_a.dot())
if args.verbose > 3:
open('final_merge.dot', 'w').write(ircfg_a.dot())
ssa = SSADiGraph(ircfg_a)
ssa.immutable_ids.update(ssa_forbidden_regs)
ssa.ssa_variable_to_expr.update(all_ssa_vars)
ssa.transform(head)
print '*'*80, "Remove phi"
if args.verbose > 3:
open('final_ssa.dot', 'w').write(ircfg_a.dot())
cfg_liveness = DiGraphLivenessSSA(ircfg_a)
cfg_liveness.init_var_info(ir_arch_a)
cfg_liveness.compute_liveness()
unssa = UnSSADiGraph(ssa, head, cfg_liveness)
if args.verbose > 3:
open('final_no_phi.dot', 'w').write(ircfg_a.dot())
modified = True
while modified:
log.debug('Loop %d', index)
index += 1
modified = False
modified |= ircfg_a.simplify(expr_simp)
if args.verbose > 3:
open('tmp_simp_%d.dot' % index, 'w').write(ircfg_a.dot())
simp_modified = True
while simp_modified:
index += 1
if args.verbose > 3:
open('tmp_before_%d.dot' % index, 'w').write(ircfg_a.dot())
simp_modified = False
simp_modified |= dead_simp(ir_arch_a, ircfg_a)
index += 1
if args.verbose > 3:
open('tmp_after_%d.dot' % index, 'w').write(ircfg_a.dot())
simp_modified |= remove_empty_assignblks(ircfg_a)
simp_modified |= merge_blocks(ircfg_a, heads)
modified |= simp_modified
index += 1
open('final.dot', 'w').write(ircfg_a.dot())
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