bindata.py

   1 "Module to deal with (binary) data of analyzed code."
   2
   3 import glob
   4 import re
   5 from collections import namedtuple
   6
   7
   8 AreaTuple = namedtuple("AreaTuple", ["start", "end", "data", "props"])
   9
  10 AREAS = []
  11
  12
  13 class InvalidAddrException(Exception):
  14     "Thrown when dereferencing address which doesn't exist in address space."
  15     def __init__(self, addr):
  16         self.args = (addr, hex(addr))
  17
  18
  19 def init(dir):
  20     "Initialize and load binary data structures."
  21     for fname in glob.glob(dir + "/*.bin"):
  22         m = re.search(r".+/([0-9A-Fa-f]+)-([0-9A-Fa-f]+)(-([A-Za-z]+))?", fname)
  23         if not m:
  24             continue
  25         with open(fname, "rb") as f:
  26             data = f.read()
  27         start = int(m.group(1), 16)
  28         end = int(m.group(2), 16)
  29         access = m.group(4).upper()
  30         AREAS.append(AreaTuple(start, end, data, {"access": access}))
  31     AREAS.sort()
  32
  33
  34 def addr2area(addr):
  35     for a in AREAS:
  36         if a.start <= addr < a.end:
  37             return (addr - a.start, a)
  38     return (None, None)
  39
  40
  41 def get_bytes(addr, sz):
  42     off, area = addr2area(addr)
  43     if area is None:
  44         raise InvalidAddrException(addr)
  45     return area.data[off:off + sz]
  46
  47
  48 def deref(addr, bits):
  49     # TODO: hardcodes little-endian
  50     res = 0
  51     bcnt = 0
  52     for b in get_bytes(addr, bits // 8):
  53         res |= b << bcnt
  54         bcnt += 8
  55     return res
  56
  57
  58 if __name__ == "__main__":
  59     init(".")
  60     print(hex(deref(0x40000054, 32)))