class Exrop(object):
def __init__(self, binary):
self.binary = binary
self.chain_builder = ChainBuilder()
def find_gadgets(self, cache=False):
if cache:
fcname = "./{}.exrop_cache".format(self.binary.replace("/", "_"))
try:
with open(fcname, "rb") as fc:
objpic = fc.read()
self.chain_builder.load_analyzed_gadgets(objpic)
return
except FileNotFoundError:
fc = open(fcname, "wb")
gadgets = parseRopGadget(self.binary)
self.chain_builder.load_list_gadget_string(gadgets)
self.chain_builder.analyzeAll()
if cache:
objpic = self.chain_builder.save_analyzed_gadgets()
fc.write(objpic)
fc.close()
def load_raw_gadgets(self, gadgets):
pass
def set_regs(self, regs, next_call=None, avoid_char=None):
self.chain_builder.set_regs(regs)
self.chain_builder.solve_chain(avoid_char)
ropchain = self.chain_builder.build_chain(next_call)
return ropchain
def set_writes(self, writes, next_call=None):
self.chain_builder.set_writes(writes)
self.chain_builder.solve_chain_write()
ropchain = self.chain_builder.build_chain(next_call)
return ropchain
def set_string(self, strs, next_call=None):
BSIZE = 8
writes = dict()
for addr, sstr in strs.items():
tmpaddr = 0
for i in range(0, len(sstr), BSIZE):
tmpstr = int.from_bytes(
bytes(sstr[i:i + BSIZE] + "\x00", 'utf-8'), 'little')
writes[addr + tmpaddr] = tmpstr
tmpaddr += BSIZE
return self.set_writes(writes, next_call)
def func_call(self, func_addr, args, rwaddr=None, convention="sysv"):
order_reg = ["rdi", "rsi", "rdx", "rcx", "r8", "r9"]
regsx86_64 = [
"rax", "rbx", "rcx", "rdx", "rsi", "rdi", "r8", "r9", "r10", "r11",
"r12", "r13", "r14", "r15"
]
regs = dict()
ropchain = RopChain()
for i in range(len(args)):
arg = args[i]
if isinstance(arg, str) and arg not in regsx86_64:
assert rwaddr, "Please define read write addr"
arg += "\x00"
chain = self.set_string({rwaddr: arg})
ropchain.merge_ropchain(chain)
regs[order_reg[i]] = rwaddr
rwaddr += len(arg)
continue
regs[order_reg[i]] = arg
chain = self.set_regs(regs, func_addr)
ropchain.merge_ropchain(chain)
return ropchain
class Exrop(object):
def __init__(self, binary):
self.binary = binary
self.chain_builder = ChainBuilder()
def find_gadgets(self, cache=False, add_opt="", num_process=1):
if cache:
fcname = "./{}.exrop_cache".format(self.binary.replace("/", "_"))
try:
with open(fcname, "rb") as fc:
objpic = fc.read()
self.chain_builder.load_analyzed_gadgets(objpic)
return
except FileNotFoundError:
fc = open(fcname, "wb")
gadgets = parseRopGadget(self.binary, add_opt)
self.chain_builder.load_list_gadget_string(gadgets)
self.chain_builder.analyzeAll(num_process)
if cache:
objpic = self.chain_builder.save_analyzed_gadgets()
fc.write(objpic)
fc.close()
def load_raw_gadgets(self, gadgets):
pass
def stack_pivot(self, addr, avoid_char=None):
self.chain_builder.solve_pivot(addr, avoid_char)
ropchain = self.chain_builder.build_chain()
return ropchain
def set_regs(self, regs, next_call=None, avoid_char=None):
self.chain_builder.set_regs(regs)
self.chain_builder.solve_chain(avoid_char)
ropchain = self.chain_builder.build_chain(next_call)
return ropchain
def set_writes(self, writes, next_call=None, avoid_char=None):
self.chain_builder.set_writes(writes)
self.chain_builder.solve_chain_write(avoid_char=avoid_char)
ropchain = self.chain_builder.build_chain(next_call)
return ropchain
def set_string(self, strs, next_call=None, avoid_char=None):
BSIZE = 8
writes = dict()
for addr, sstr in strs.items():
tmpaddr = 0
sstr += "\x00"
for i in range(0, len(sstr), BSIZE):
tmpstr = int.from_bytes(bytes(sstr[i:i + BSIZE], 'utf-8'),
'little')
writes[addr + tmpaddr] = tmpstr
tmpaddr += BSIZE
return self.set_writes(writes, next_call, avoid_char=avoid_char)
def func_call(self,
func_addr,
args,
rwaddr=None,
convention="sysv",
type_val_addr=0,
comment=""):
call_convention = {
"sysv": ["rdi", "rsi", "rdx", "rcx", "r8", "r9"],
"syscall_x86-64": ["rax", "rdi", "rsi", "rdx", "r10", "r8", "r9"]
}
order_reg = call_convention[convention]
regsx86_64 = [
"rax", "rbx", "rcx", "rdx", "rsi", "rdi", "r8", "r9", "r10", "r11",
"r12", "r13", "r14", "r15"
]
regs = dict()
ropchain = RopChain()
for i in range(len(args)):
arg = args[i]
if isinstance(arg, str) and arg not in regsx86_64:
assert rwaddr, "Please define read write addr"
chain = self.set_string({rwaddr: arg})
ropchain.merge_ropchain(chain)
regs[order_reg[i]] = rwaddr
rwaddr += len(arg) + 1 # for null byte
continue
regs[order_reg[i]] = arg
chain = self.set_regs(regs)
ropchain.merge_ropchain(chain)
ropchain.set_next_call(func_addr, type_val_addr, comment=comment)
return ropchain
def syscall(self, sysnum, args, rwaddr=None):
reg_used_syscall = set(["rax", "rdi", "rsi", "rdx", "r10", "r8", "r9"])
args = (sysnum, ) + args
syscall = self.chain_builder.get_syscall_addr(
not_write_regs=reg_used_syscall)
assert syscall, "can't find syscall gadget!"
chain = self.func_call(syscall.addr,
args,
rwaddr,
convention="syscall_x86-64",
type_val_addr=1,
comment=str(syscall))
if syscall.end_type != TYPE_RETURN:
chain.is_noreturn = True
return chain