isoc-py3/isoc-py3.py
2024-11-09 11:33:07 -05:00

531 lines
16 KiB
Python
Executable file

#!/usr/bin/env python3
import logging
logging.basicConfig(level=logging.ERROR)
import base64
import binascii
import bz2
import calendar
import datetime
import os
import random
import struct
from collections import defaultdict
from errno import ENOENT
from stat import S_IFDIR, S_IFLNK, S_IFREG
from sys import argv, exit
from time import time
from time import localtime
from time import strftime
from time import mktime
from fuse import FUSE, FuseOSError, Operations, LoggingMixIn
ISO9660_BOOT_BLK = bz2.decompress(
base64.b64decode(
"""
QlpoOTFBWSZTWf7EvQUAAFv//fREJgRSAWAALyXeECYGQAQAQBkAABAgCACAEAAACLAAuSEpAk0bS
NNBpoNHqNNHqD1NDAGmho0YjIBoANDBFJINGjQAAAABo67j0bZyRUa5yTYIQ4kKTEIUwAXoAFqrSW
4rKEBSAhABlCEiGmEFTMYxS2moWhFsmA6oWhYpKyEGJZcHEC6HB+P3rMF7qCe92GE9TJlRStvcUio
nnIx8jGJrKA+I80GdJI5JNH6AqxFBNVCiJ+/i7kinChIf2JegoA==
"""
)
)
epoch = datetime.datetime.fromtimestamp(0, datetime.UTC)
CDATE_FREQ = 49710
CDATE_YEAR_DAYS_INT = 36524225
CDIR_FILENAME_LEN = 38
RS_ATTR_READ_ONLY = 0x01 # R
RS_ATTR_HIDDEN = 0x02 # H
RS_ATTR_SYSTEM = 0x04 # S
RS_ATTR_VOL_ID = 0x08 # V
RS_ATTR_DIR = 0x10 # D
RS_ATTR_ARCHIVE = 0x20 # A
RS_ATTR_DELETED = 0x100 # X
RS_ATTR_RESIDENT = 0x200 # T
RS_ATTR_COMPRESSED = 0x400 # Z
RS_ATTR_CONTIGUOUS = 0x800 # C
RS_ATTR_FIXED = 0x1000 # F
RS_BLK_SIZE = 512
RS_DRV_OFFSET = 0xB000
RS_ROOT_CLUS = 0x5A
mon_start_days1 = [0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334]
mon_start_days2 = [0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335]
def roundup(x):
return x if x % 2048 == 0 else x + 2048 - x % 2048
def write_iso_c(self, iso_c_file):
dirs = []
dir_entries = {}
# Create dict for each directory
for i in self.files:
if self.files[i]["st_mode"] & 40000 == 64:
dir_entries[i] = {}
dir_entries[i]["clus"] = 0
dir_entries[i]["files"] = []
dir_entries[i]["files"].append(
{
"filename": ".",
"clus": 0,
"st_size": 0x400,
"st_mode": 64,
"st_mtime": time(),
}
)
dir_entries[i]["files"].append(
{
"filename": "..",
"clus": 0,
"st_size": 0x00,
"st_mode": 64,
"st_mtime": time(),
}
)
dirs.append(i)
# Place files in corresponding dicts
for d in sorted(dirs, reverse=True):
for i in self.files:
if i.find((d + "/").replace("//", "/")) != -1 and i != d:
if "filename" not in self.files[i]:
self.files[i]["filename"] = i.split("/")[len(i.split("/")) - 1]
self.files[i]["clus"] = 0
dir_entries[d]["files"].append(self.files[i])
# Calculate CDirEntry clusters
de_tbl_size = 0
de_clus_ctr = RS_ROOT_CLUS
for d in sorted(dir_entries):
ct_entries = 1 + len(dir_entries[d]["files"])
ct_size = RS_BLK_SIZE * int((1 + (ct_entries * 64) / RS_BLK_SIZE))
de_tbl_size += ct_size
dir_entries[d]["clus"] = de_clus_ctr
de_clus_ctr += int((ct_size / RS_BLK_SIZE))
# Link nested CDirEntries
for d in dirs:
de_filename = d[d.rfind("/") + 1 :]
if len(d.split("/")) > 2:
de_parent = d[: d.rfind("/")]
else:
de_parent = "/"
de_idx = 0
for de in dir_entries[de_parent]["files"]:
if de["filename"] == de_filename:
dir_entries[de_parent]["files"][de_idx]["clus"] = dir_entries[
(de_parent + "/" + de_filename).replace("//", "/")
]["clus"]
de_idx += 1
# Link dotted dirs ".", ".."
for de_parent in dir_entries:
de_idx = 0
for de in dir_entries[de_parent]["files"]:
if de["filename"] == ".":
dir_entries[de_parent]["files"][de_idx]["clus"] = dir_entries[
de_parent
]["clus"]
# Calculate length of this directory
dir_entries[de_parent]["files"][de_idx]["st_size"] = RS_BLK_SIZE * (
1 + int(64 * (len(dir_entries[de_parent]["files"])) / RS_BLK_SIZE)
)
if de["filename"] == "..":
dir_entries[de_parent]["files"][de_idx]["clus"] = dir_entries[
("/" + de_parent[: de_parent.rfind("/")]).replace("//", "/")
]["clus"]
de_idx += 1
# Update size for subdir entries
for de_parent in dir_entries:
de_idx = 0
for de in dir_entries[de_parent]["files"]:
if (
de["st_mode"] & 40000 == 64
and de["filename"] != "."
and de["filename"] != ".."
):
for sde in dir_entries[
(de_parent + "/" + de["filename"]).replace("//", "/")
]["files"]:
if sde["filename"] == ".":
dir_entries[de_parent]["files"][de_idx]["st_size"] = sde[
"st_size"
]
de_idx += 1
# Calculate cluster offset for files
for de_parent in dir_entries:
de_idx = 0
for de in dir_entries[de_parent]["files"]:
if de["clus"] == 0:
dir_entries[de_parent]["files"][de_idx]["clus"] = de_clus_ctr
ct_size = RS_BLK_SIZE * int((1 + (de["st_size"]) / RS_BLK_SIZE))
de_clus_ctr += int((ct_size / RS_BLK_SIZE))
de_idx += 1
file = open(iso_c_file, "wb")
# Write ISO9660 boot block
file.seek(0)
file.write(ISO9660_BOOT_BLK)
# Write CDirEntries
for d in sorted(dirs):
de_offset = int(dir_entries[d]["clus"] * RS_BLK_SIZE)
for f in sorted(dir_entries[d]["files"], key=lambda k: k["filename"]):
file.seek(de_offset)
if f["st_mode"] & 40000 == 64:
# Directory
file.write(b"\x10")
else:
# File
file.write(b"\x20")
if f["filename"][-2:] == ".Z":
file.write(b"\x0c")
else:
file.write(b"\x08")
file.write(f["filename"].ljust(CDIR_FILENAME_LEN, "\0").encode("utf-8"))
# Cluster, Size, DateTime
dt = Unix2CDate(localtime(f["st_mtime"] + 1))
file.seek(de_offset + 0x28)
file.write(
struct.pack("<QQLL", int(f["clus"]), int(f["st_size"]), dt[1], dt[0])
)
de_offset += 64
# Write files
for d in sorted(dirs):
de_offset = int(dir_entries[d]["clus"] * RS_BLK_SIZE)
for f in sorted(dir_entries[d]["files"], key=lambda k: k["filename"]):
file.seek(de_offset)
if f["st_mode"] & 40000 != 64:
file.seek(int(f["clus"] * RS_BLK_SIZE))
file.write(self.data[(d + "/" + f["filename"]).replace("//", "/")])
# Set counter to byte multiple 2048
de_clus_ctr = roundup(de_clus_ctr)
# Write to EOF
file.seek(RS_DRV_OFFSET + int(de_clus_ctr * RS_BLK_SIZE) - 1)
file.write(b"\0")
# Write boot sector
bs = [0x00] * RS_BLK_SIZE
bs[0x003] = 0x88 # signature
bs[0x008] = 0x58 # cdrom offset
# -- cluster count
cl_sz = binascii.unhexlify(format(int(de_clus_ctr), "016X"))
cl_sz_ctr = 0
while cl_sz_ctr < 8:
bs[0x10 + cl_sz_ctr] = cl_sz[7 - cl_sz_ctr]
cl_sz_ctr += 1
bs[0x018] = 0x5A # root entry cluster [90]
bs[0x020] = 0x01 # bitmap_sects (unused for ISO.C?)
# -- unique id
id_ctr = 0
while id_ctr < 8:
bs[0x028 + id_ctr] = int(random.random() * 256) % 256
id_ctr += 1
bs[0x1FE] = 0x55 # signature
bs[0x1FF] = 0xAA # signature
file.seek(RS_DRV_OFFSET)
file.write(bytes(bs))
file.close()
def CDate2Unix(c_date, c_time):
year = int((c_date + 1) * 100000 / CDATE_YEAR_DAYS_INT)
c_year = int(year)
i = YearStartDate(c_year)
while i > c_date:
c_year -= 1
i = YearStartDate(c_year)
c_date -= i
c_date = int(c_date)
if calendar.isleap(year) and c_date > 29:
c_date += 1
hours = 0
minutes = 0
seconds = c_time / CDATE_FREQ
while seconds > 3599:
hours += 1
seconds -= 3600
while seconds > 59:
minutes += 1
seconds -= 60
return datetime.datetime(year, 1, 1) + datetime.timedelta(
days=int(c_date), hours=hours, minutes=minutes, seconds=seconds
)
def is_dst(dt):
if dt.year < 2007:
# huehuehue
return False
dst_start = datetime.datetime(dt.year, 3, 8, 2, 0)
dst_start += datetime.timedelta(6 - dst_start.weekday())
dst_end = datetime.datetime(dt.year, 11, 1, 2, 0)
dst_end += datetime.timedelta(6 - dst_end.weekday())
return dst_start <= dt < dst_end
def YearStartDate(year):
y1 = year - 1
yd4000 = y1 / 4000
yd400 = y1 / 400
yd100 = y1 / 100
yd4 = y1 / 4
return year * 365 + yd4 - yd100 + yd400 - yd4000
def Unix2CDate(dt):
il = YearStartDate(dt.tm_year)
i2 = YearStartDate(dt.tm_year + 1)
if i2 - il == 365:
il += mon_start_days1[dt.tm_mon - 1]
else:
il += mon_start_days2[dt.tm_mon - 1]
_date = il + (dt.tm_mday - 1)
_time = (100 * (100 * (dt.tm_sec + 60 * (dt.tm_min + 60 * dt.tm_hour))) << 21) / (
15 * 15 * 3 * 625
)
return [int(_date), int(_time)]
class RedSea(LoggingMixIn, Operations):
def __init__(self, iso_c_file):
self.files = {}
self.data = defaultdict(bytes)
self.fd = 0
self.modified = False
now = time()
self.files["/"] = dict(
st_mode=(S_IFDIR | 0o755),
st_ctime=now,
st_mtime=now,
st_atime=now,
st_nlink=2,
)
iso_c_file_exists = os.path.exists(iso_c_file)
if iso_c_file_exists:
f = open(iso_c_file, "rb").read()
blkdev_offset = RS_DRV_OFFSET
de_list = {
"": blkdev_offset
+ int((1 + int(f[blkdev_offset + 0x20])) * RS_BLK_SIZE)
}
else:
de_list = {}
# If iso_c_file exists, read dirs/files
while len(de_list) > 0 and iso_c_file_exists:
current_de = list(de_list.keys())[0]
dir = current_de + "/"
ofs = de_list[current_de]
del de_list[current_de]
# Go to first CDirEntry, skipping ".", ".."
pos = 128
while int(f[ofs + pos + 2]) != 0x00:
ctr = int(ofs + pos)
de_attrs = struct.unpack("<H", f[ctr : ctr + 2])[0]
ctr += 2
de_filename = (
f[ctr : ctr + CDIR_FILENAME_LEN].decode("utf-8").replace("\0", "")
)
ctr += CDIR_FILENAME_LEN
de_clus = struct.unpack("<q", f[ctr : ctr + 8])[0]
ctr += 8
de_size = struct.unpack("<q", f[ctr : ctr + 8])[0]
ctr += 8
de_time = struct.unpack("<l", f[ctr : ctr + 4])[0]
de_date = struct.unpack("<l", f[ctr + 4 : ctr + 8])[0]
ctr += 8
de_mode = S_IFREG | 0o755
if de_attrs & RS_ATTR_DIR:
de_mode = S_IFDIR | 0o755
de_list[dir + de_filename] = (int(de_clus)) * RS_BLK_SIZE
self.files[dir + de_filename] = dict(
st_mode=de_mode,
st_ctime=mktime(CDate2Unix(de_date, de_time).timetuple()),
st_mtime=mktime(CDate2Unix(de_date, de_time).timetuple()),
st_atime=now,
st_nlink=2,
st_size=de_size,
)
if not de_attrs & RS_ATTR_DIR:
self.data[dir + de_filename] = f[
RS_BLK_SIZE * de_clus : (RS_BLK_SIZE * de_clus) + de_size
]
pos += 64
if iso_c_file_exists:
del f
def chmod(self, path, mode):
self.files[path]["st_mode"] &= 0o770000
self.files[path]["st_mode"] |= mode
return 0
def chown(self, path, uid, gid):
self.files[path]["st_uid"] = uid
self.files[path]["st_gid"] = gid
def create(self, path, mode):
self.files[path] = dict(
st_mode=(S_IFREG | mode),
st_nlink=1,
st_size=0,
st_ctime=time(),
st_mtime=time(),
st_atime=time(),
)
self.fd += 1
self.modified = True
return self.fd
def getattr(self, path, fh=None):
if path not in self.files:
raise FuseOSError(ENOENT)
return self.files[path]
def getxattr(self, path, name, position=0):
attrs = self.files[path].get("attrs", {})
try:
return attrs[name]
except KeyError:
return "" # Should return ENOATTR
def listxattr(self, path):
attrs = self.files[path].get("attrs", {})
return attrs.keys()
def mkdir(self, path, mode):
self.files[path] = dict(
st_mode=(S_IFDIR | mode),
st_nlink=2,
st_size=0,
st_ctime=time(),
st_mtime=time(),
st_atime=time(),
)
self.files["/"]["st_nlink"] += 1
self.modified = True
def open(self, path, flags):
self.fd += 1
return self.fd
def read(self, path, size, offset, fh):
return self.data[path][offset : offset + size]
def readdir(self, path, fh):
dir = [".", ".."]
if path == "/":
for f in self.files:
if f.rfind("/") == 0 and f != "/":
dir.append(str(f)[1:])
else:
for f in self.files:
if len(f.split(path)) > 1:
if f.split(path)[1].rfind("/") == 0 and f.split(path)[1] != "/":
dir.append(str(f.split(path)[1])[1:])
return dir
def readlink(self, path):
return self.data[path]
def removexattr(self, path, name):
attrs = self.files[path].get("attrs", {})
try:
del attrs[name]
except KeyError:
pass # Should return ENOATTR
def rename(self, old, new):
self.files[new] = self.files.pop(old)
self.modified = True
def rmdir(self, path):
self.files.pop(path)
self.files["/"]["st_nlink"] -= 1
self.modified = True
def setxattr(self, path, name, value, options, position=0):
# Ignore options
attrs = self.files[path].setdefault("attrs", {})
attrs[name] = value
def statfs(self, path):
size = 256
return dict(
f_bsize=RS_BLK_SIZE,
f_blocks=((size * 1024) * 2),
f_bavail=((size * 1024) * 2),
)
def symlink(self, target, source):
self.files[target] = dict(
st_mode=(S_IFLNK | 0o777), st_nlink=1, st_size=len(source)
)
self.data[target] = source
def truncate(self, path, length, fh=None):
self.data[path] = self.data[path][:length]
self.files[path]["st_size"] = length
def unlink(self, path):
self.files.pop(path)
self.modified = True
def utimens(self, path, times=None):
now = time()
atime, mtime = times if times else (now, now)
self.files[path]["st_atime"] = atime
self.files[path]["st_mtime"] = mtime
def write(self, path, data, offset, fh):
self.data[path] = self.data[path][:offset] + data
self.files[path]["st_size"] = len(self.data[path])
self.modified = True
return len(data)
def destroy(self, d):
if self.modified and argv[3] == "rw":
write_iso_c(self, argv[1])
if __name__ == "__main__":
fuse = FUSE(RedSea(argv[1]), argv[2], foreground=True)