81 lines
2.6 KiB
Python
81 lines
2.6 KiB
Python
|
"""LUKS key management plus crypttab/fstab bookkeeping."""
|
||
|
|
|
||
|
|
import re
|
||
|
|
from pathlib import Path
|
||
|
|
|
||
|
|
from lim import fsutil, runner, ui
|
||
|
|
from lim.errors import LimError
|
||
|
|
|
||
|
|
LUKS_KEY_DIRECTORY = Path("/etc/luks-keys")
|
||
|
|
CRYPTTAB_PATH = Path("/etc/crypttab")
|
||
|
|
FSTAB_PATH = Path("/etc/fstab")
|
||
|
|
|
||
|
|
|
||
|
|
def luks_uuid(partition_path: str) -> str:
|
||
|
|
dump = runner.output(["cryptsetup", "luksDump", partition_path], sudo=True)
|
||
|
|
match = re.search(r"UUID:\s*(\S+)", dump)
|
||
|
|
if not match:
|
||
|
|
raise LimError(f"Could not read LUKS UUID of {partition_path}.")
|
||
|
|
return match.group(1)
|
||
|
|
|
||
|
|
|
||
|
|
def create_luks_key_and_update_crypttab(
|
||
|
|
mapper_name: str,
|
||
|
|
partition_path: str,
|
||
|
|
*,
|
||
|
|
key_directory: Path = LUKS_KEY_DIRECTORY,
|
||
|
|
crypttab_path: Path = CRYPTTAB_PATH,
|
||
|
|
) -> None:
|
||
|
|
"""Generate a random keyfile, register it with LUKS and /etc/crypttab."""
|
||
|
|
ui.info("Creating luks-key-directory...")
|
||
|
|
key_directory.mkdir(parents=True, exist_ok=True)
|
||
|
|
secret_key_path = key_directory / f"{mapper_name}.keyfile"
|
||
|
|
ui.info(f"Generate secret key under: {secret_key_path}")
|
||
|
|
if secret_key_path.exists():
|
||
|
|
ui.warning("File already exists. Overwriting!")
|
||
|
|
runner.run(
|
||
|
|
["dd", "if=/dev/urandom", f"of={secret_key_path}", "bs=512", "count=8"],
|
||
|
|
sudo=True,
|
||
|
|
)
|
||
|
|
runner.sync_disks()
|
||
|
|
|
||
|
|
ui.info("Opening and closing device to verify that everything works fine...")
|
||
|
|
closed = runner.run(
|
||
|
|
["cryptsetup", "-v", "luksClose", mapper_name], sudo=True, check=False
|
||
|
|
)
|
||
|
|
if closed.returncode != 0:
|
||
|
|
ui.info(f"No need to luksClose {mapper_name}. Device isn't open.")
|
||
|
|
runner.run(
|
||
|
|
["cryptsetup", "luksAddKey", partition_path, str(secret_key_path)], sudo=True
|
||
|
|
)
|
||
|
|
runner.run(
|
||
|
|
[
|
||
|
|
"cryptsetup",
|
||
|
|
"-v",
|
||
|
|
"luksOpen",
|
||
|
|
partition_path,
|
||
|
|
mapper_name,
|
||
|
|
f"--key-file={secret_key_path}",
|
||
|
|
],
|
||
|
|
sudo=True,
|
||
|
|
)
|
||
|
|
runner.run(["cryptsetup", "-v", "luksClose", mapper_name], sudo=True)
|
||
|
|
|
||
|
|
ui.info("Reading UUID...")
|
||
|
|
uuid = luks_uuid(partition_path)
|
||
|
|
entry = f"{mapper_name} UUID={uuid} {secret_key_path} luks"
|
||
|
|
ui.info("Adding crypttab entry...")
|
||
|
|
fsutil.ensure_line_in_file(entry, crypttab_path)
|
||
|
|
ui.info(f"The file {crypttab_path} contains now the following:")
|
||
|
|
print(crypttab_path.read_text())
|
||
|
|
|
||
|
|
|
||
|
|
def update_fstab(
|
||
|
|
mapper_path: str, mount_path: str, *, fstab_path: Path = FSTAB_PATH
|
||
|
|
) -> None:
|
||
|
|
entry = f"{mapper_path} {mount_path} btrfs defaults 0 2"
|
||
|
|
ui.info("Adding fstab entry...")
|
||
|
|
fsutil.ensure_line_in_file(entry, fstab_path)
|
||
|
|
ui.info(f"The file {fstab_path} contains now the following:")
|
||
|
|
print(fstab_path.read_text())
|