Files
ext4recovery/misc_tools/digging.py
2026-04-30 11:04:05 +00:00

108 lines
3.7 KiB
Python

import struct
CHUNK = 128*512
LV_START = 5120000*512
BSIZE = 4096
IPG = 8192
def read_virt(virt_byte, length):
result = bytearray(length)
pos = virt_byte
remaining = length
with open('/dev/md0','rb') as f:
while remaining > 0:
group = pos // (5*CHUNK)
in_group = pos % (5*CHUNK)
chunk_idx = in_group // CHUNK
intra = in_group % CHUNK
seg_len = min(CHUNK-intra, remaining)
dst_off = pos - virt_byte
if chunk_idx != 4:
phys = LV_START + group*4*CHUNK + chunk_idx*CHUNK + intra
f.seek(phys)
data = f.read(seg_len)
result[dst_off:dst_off+len(data)] = data
pos += seg_len
remaining -= seg_len
return bytes(result)
# Cache GDT
print('Loading full GDT...')
NUM_GROUPS = 35728
gdt_data = read_virt(BSIZE, NUM_GROUPS*64)
print(f'GDT loaded: {len(gdt_data)} bytes')
def get_inode_table_block(group):
entry = gdt_data[group*64:(group+1)*64]
it_lo = struct.unpack_from('<I', entry, 8)[0]
it_hi = struct.unpack_from('<I', entry, 40)[0]
return (it_hi<<32)|it_lo
def read_inode(inode_num):
group = (inode_num-1)//IPG
idx = (inode_num-1)%IPG
it_block = get_inode_table_block(group)
return read_virt(it_block*BSIZE + idx*256, 256)
def get_extents(inode_data):
blocks = []
if struct.unpack_from('<H', inode_data, 40)[0] != 0xf30a:
return blocks
entries = struct.unpack_from('<H', inode_data, 42)[0]
depth = struct.unpack_from('<H', inode_data, 46)[0]
if depth == 0:
for i in range(min(entries,4)):
off = 52+i*12
ee_len = struct.unpack_from('<H', inode_data, off+4)[0]
ee_hi = struct.unpack_from('<H', inode_data, off+6)[0]
ee_lo = struct.unpack_from('<I', inode_data, off+8)[0]
start = (ee_hi<<32)|ee_lo
if ee_len > 1024: continue
for b in range(min(ee_len,8)):
blocks.append(start+b)
return blocks
def list_dir(inode_num):
inode_data = read_inode(inode_num)
mode = struct.unpack_from('<H', inode_data, 0)[0]
if (mode&0xf000) != 0x4000:
return []
entries = []
for blk in get_extents(inode_data):
blk_data = read_virt(blk*BSIZE, BSIZE)
off = 0
while off < BSIZE-8:
ino = struct.unpack_from('<I', blk_data, off)[0]
rec_len = struct.unpack_from('<H', blk_data, off+4)[0]
name_len= blk_data[off+6]
ftype = blk_data[off+7]
if rec_len < 8: break
if ino > 0 and name_len > 0:
name = blk_data[off+8:off+8+name_len].decode('utf-8',errors='replace')
if name not in ('.','..'):
entries.append((ino, name, ftype))
off += rec_len
return entries
# Walk tree from /var
print()
print('=== /var (inode 1310721) ===')
for ino, name, ftype in list_dir(1310721):
tname = {1:'file',2:'dir',7:'link'}.get(ftype,'?')
print(f' {tname:4s} inode={ino:10d} {name!r}')
print()
for ino, name, ftype in list_dir(1310721):
if name == 'lib':
print(f'=== /var/lib (inode {ino}) ===')
for i2,n2,f2 in list_dir(ino):
tname = {1:'file',2:'dir',7:'link'}.get(f2,'?')
print(f' {tname:4s} inode={i2:10d} {n2!r}')
for i2,n2,f2 in list_dir(ino):
if n2 == 'pterodactyl':
print(f'\n=== /var/lib/pterodactyl (inode {i2}) ===')
for i3,n3,f3 in list_dir(i2):
tname = {1:'file',2:'dir',7:'link'}.get(f3,'?')
print(f' {tname:4s} inode={i3:10d} {n3!r}')