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@murachue
Created June 16, 2012 18:09
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.fds file loader for IDA (IDAPython)
# IDA .fds Loader
# usage:
# 1. Place into $IDA/loader/
# 2. Open .fds file by IDA (select "Python FDS Loader")
# 3. "import fds; fds.add()" and select additional file
# Enjoy!
# reference:
# http://park19.wakwak.com/~fantasy/fds/
import idaapi
import struct
class Struc:
def __init__(self, pairs):
"""
struc = Struc([["8s","name"],["B","id"],...])
"""
self.fmt = "".join(map(lambda e:e[0],pairs))
self.keys = map(lambda e:e[1],pairs)
def read(self, li):
"""
dict = struc.read(li)
"""
#print "reading fmt " + self.fmt
values = struct.unpack(self.fmt, li.read(struct.calcsize(self.fmt)))
self.dict = {}
for i in xrange(len(self.keys)):
self.dict[self.keys[i]] = values[i]
return self.dict
class QuickDisk:
def __init__(self, li):
# IMPORTANT! seek to head!
li.seek(0)
# load files
signat = li.read(4)
if signat != "FDS\x1a":
print "WARNING: FDS without ident? (%s)" % signat
total_sides = struct.unpack("B", li.read(1))
li.read(0x10 - 4 - 1)
self.files = []
self.bootno = []
vlabel = None
filecnt = None
pblkcode = None
nowfilecnt = 0
# support both IDA-linput and Python-File
filesize = 0
try:
filesize = li.size()
except:
ptell = li.tell()
li.seek(0, 2) # TODO 2!? no SEEK_END!?
filesize = li.tell()
li.seek(ptell)
while True:
if filesize <= li.tell():
break
if filecnt != None and filecnt <= nowfilecnt:
# next side
li.seek(((li.tell() - 0x10 + (65500-1)) / 65500) * 65500 + 0x10)
nowfilecnt = 0
if filesize <= li.tell():
break
side = (li.tell() - 0x10) / 65500
if total_sides < side:
print "WARNING: unexpected tail data"
total_sides = side
blkcode = struct.unpack("B", li.read(1))[0]
if blkcode == 0:
# tail or gap??
pass
elif blkcode == 1:
# volume label
vlabel = Struc([
["14s", "chkcode"],
["B", "maker"],
["4s", "gamename"],
["B", "gamever"],
["B", "diskside"],
["B", "diskno"],
["B", "disktype"],
["B", "unk1"],
["B", "bootno"],
["5s", "unk2"],
["3s", "date"],
["B", "unk3"],
["B", "unk4"],
["H", "writerid"], # TODO something goes wrong?
["B", "unk5"],
["B", "rewritecnt"],
["B", "real_diskside"],
["B", "unk6"],
["B", "crc"],
["12s", "no_doced"],
]).read(li)
#print "vlabel>>>",vlabel
filecnt = None
self.bootno.append(vlabel["bootno"])
elif blkcode == 2:
# file count
filecnt = struct.unpack("B", li.read(1))[0]
#print "fcount>>>",filecnt
elif blkcode == 3:
# file header
header = Struc([
["B", "seqno"],
["B", "ldno"],
["8s", "name"],
["H", "addr"],
["H", "size"],
["B", "target"],
]).read(li)
header["side"] = side
header["side_str"] = chr(ord("A") + side)
header["boot"] = (header["ldno"] <= vlabel["bootno"])
#print header
self.files.append(header)
# TODO check seqno sequence, check seqno < filecnt
elif blkcode == 4:
if pblkcode != 3:
print "WARNING: blkcode %X -> 4" % (pblkcode,)
# file data
file = self.files[-1]
file["offset"] = li.tell()
file["data"] = li.read(file["size"])
nowfilecnt += 1
else:
# tell-1 = &blkcode
print "offset %X blkcode %X?" % (li.tell() - 1, blkcode)
pblkcode = blkcode
#def files():
# return self.files
class FileSelector(idaapi.Choose2):
def __init__(self, li):
title = "Choose a file from FDS FileList"
cols = [
["Offset", 5 | idaapi.Choose2.CHCOL_HEX],
["Side", 2 | idaapi.Choose2.CHCOL_PLAIN],
["SeqNo", 2 | idaapi.Choose2.CHCOL_HEX],
["LoadNo", 2 | idaapi.Choose2.CHCOL_HEX],
["Filename", 10 | idaapi.Choose2.CHCOL_PLAIN],
["Addr", 4 | idaapi.Choose2.CHCOL_HEX],
["Size", 4 | idaapi.Choose2.CHCOL_HEX],
["Target", 2 | idaapi.Choose2.CHCOL_HEX],
]
idaapi.Choose2.__init__(self, title, cols)
files = QuickDisk(li).files
#files = filter(lambda x:x["target"] == 0, files) # TODO filter: only texts?
self.files = files
def OnGetSize(self):
return len(self.files)
def OnGetLine(self, n):
file = self.files[n]
return [
hex(file["offset"]),
file["side_str"] + ("*" if file["boot"] else ""),
hex(file["seqno"]),
hex(file["ldno"]),
file["name"],
hex(file["addr"]),
hex(file["size"]),
hex(file["target"]),
]
def OnClose(self):
pass
def show(self):
i = self.Show(True)
if i == -1:
return None
else:
return self.files[i]
def accept_file(li, n):
if n > 0:
return 0
if li.read(4) != "FDS\x1a":
return 0
return "Python FDS Loader"
def make_io():
# TODO make name to io-port... and DISK-BIOS functions?
idaapi.add_segm(0, 0x0000, 0x0800, "RAM", "DATA")
idaapi.add_segm(0, 0x2000, 0x2008, "PPU", "DATA")
idaapi.add_segm(0, 0x4000, 0x4018, "CPU", "DATA")
idaapi.add_segm(0, 0x4022, 0x408B, "DISKIO", "DATA")
#idaapi.add_segm(0, 0x4100, 0x6000, "EXT", "DATA") # non-need?
#idaapi.add_segm(0, 0xE000, 0x10000, "BIOS", "UNK") # add BIOS image by yourself...
def load_file(li, neflags, format):
if format != "Python FDS Loader":
return 0
# 6502 (2A03 is best)
idaapi.set_processor_type("M6502", SETPROC_ALL|SETPROC_FATAL)
# try to user to be choose?
#return add_li(li)
# or autoload boot-files?
# only see side-A.
qd = QuickDisk(li)
for file in filter(lambda f:f["target"] == 0 and f["ldno"] <= qd.bootno[0], qd.files):
load_li(li, file)
make_io()
return 1
def make_offs_name(ea, name):
idaapi.set_name(ea, name)
idaapi.doWord(ea, 2)
idaapi.set_offset(ea, 0, 0)
def load_li(li, file):
# file2base(li,pos,ea1,ea2,patchable) FILEREG_NOTPATCHABLE
# mem2base(mem,ea,fpos)
#idaapi.file2base(li, file["offset"], file["addr"], file["addr"]+file["size"], idaapi.FILEREG_NOTPATCHABLE)
#idaapi.mem2base(file["data"], file["addr"], file["addr"]+file["size"], file["offset"])
# TODO I want to make segment type "CODE" but IDA tries to analysis...
idaapi.add_segm(0, file["addr"], file["addr"]+file["size"], "%s%X" % (file["side_str"], file["seqno"]), "UNK")
idaapi.mem2base(file["data"], file["addr"], file["offset"])
# special-handling: vectors
if file["addr"] <= 0xDFFA and 0xDFFF <= file["addr"]+file["size"]:
make_offs_name(0xDFFA, "NMIVEC")
make_offs_name(0xDFFC, "RSTVEC")
make_offs_name(0xDFFE, "IRQVEC")
def add_li(li):
"""
@hide
"""
file = FileSelector(li).show()
if file == None:
return 0
load_li(li, file)
return 1
def add():
"""
user accessible API.
fds.add()
"""
f = None
try:
f = open(idaapi.get_input_file_path(), "rb")
except IOError:
print "fds: Can't open input file."
return 0
r = add_li(f)
f.close()
return r
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