binaryninja-api/python/examples/jump_table.py at dev · Vector35/binaryninja-api · GitHub

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# Permission is hereby granted, free of charge, to any person obtaining a copy

# of this software and associated documentation files (the "Software"), to

# deal in the Software without restriction, including without limitation the

# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or

# sell copies of the Software, and to permit persons to whom the Software is

# furnished to do so, subject to the following conditions:

# The above copyright notice and this permission notice shall be included in

# all copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS

# IN THE SOFTWARE.

# This plugin will attempt to resolve simple jump tables (an array of code pointers) and add the destinations

# as indirect branch targets so that the flow graph reflects the jump table's control flow.

from binaryninja.plugin import PluginCommand

from binaryninja.enums import InstructionTextTokenType

import struct

def find_jump_table(bv, addr):

for block in bv.get_basic_blocks_at(addr):

func = block.function

arch = func.arch

addrsize = arch.address_size

# Grab the instruction tokens so that we can look for the table's starting address

tokens, length = arch.get_instruction_text(bv.read(addr, 16), addr)

# Look for the next jump instruction, which may be the current instruction. Some jump tables will

# compute the address first then jump to the computed address as a separate instruction.

jump_addr = addr

while jump_addr < block.end:

info = arch.get_instruction_info(bv.read(jump_addr, 16), jump_addr)

if len(info.branches) != 0:

break

jump_addr += info.length

if jump_addr >= block.end:

print("Unable to find jump after instruction 0x%x" % addr)

continue

print("Jump at 0x%x" % jump_addr)

# Collect the branch targets for any tables referenced by the clicked instruction

branches = []

for token in tokens:

if InstructionTextTokenType(

token.type

) == InstructionTextTokenType.PossibleAddressToken: # Table addresses will be a "possible address" token

tbl = token.value

print("Found possible table at 0x%x" % tbl)

i = 0

while True:

# Read the next pointer from the table

data = bv.read(tbl + (i*addrsize), addrsize)

if len(data) == addrsize:

if addrsize == 4:

ptr = struct.unpack("<I", data)[0]

else:

ptr = struct.unpack("<Q", data)[0]

# If the pointer is within the binary, add it as a destination and continue

# to the next entry

if (ptr >= bv.start) and (ptr < bv.end):

print("Found destination 0x%x" % ptr)

branches.append((arch, ptr))

else:

# Once a value that is not a pointer is encountered, the jump table is ended

break

else:

# Reading invalid memory

break

i += 1

# Set the indirect branch targets on the jump instruction to be the list of targets discovered

func.set_user_indirect_branches(jump_addr, branches)

# Create a plugin command so that the user can right click on an instruction referencing a jump table and

# invoke the command

PluginCommand.register_for_address("Process jump table", "Look for jump table destinations", find_jump_table)

binaryninja-api/python/examples/jump_table.py at dev · Vector35/binaryninja-api · GitHub

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