rewrite sops backend for secret generation and add tests

This commit is contained in:
Jörg Thalheim
2023-09-19 21:48:39 +02:00
committed by lassulus
parent ead5c6e6a8
commit 0314132a1a
9 changed files with 287 additions and 74 deletions

View File

@@ -0,0 +1,9 @@
from .folders import machine_folder
def machine_has_fact(machine: str, fact: str) -> bool:
return (machine_folder(machine) / "facts" / fact).exists()
def machine_get_fact(machine: str, fact: str) -> str:
return (machine_folder(machine) / "facts" / fact).read_text()

View File

@@ -1,5 +1,8 @@
import json
import os
import subprocess
import tempfile
from typing import Any
from .dirs import nixpkgs_flake, nixpkgs_source, unfree_nixpkgs
@@ -25,6 +28,16 @@ def nix_build(
)
def nix_config() -> dict[str, Any]:
cmd = nix_command(["show-config", "--json"])
proc = subprocess.run(cmd, check=True, text=True, stdout=subprocess.PIPE)
data = json.loads(proc.stdout)
config = {}
for key, value in data.items():
config[key] = value["value"]
return config
def nix_eval(flags: list[str]) -> list[str]:
default_flags = nix_command(
[

View File

@@ -1,31 +1,41 @@
import argparse
import os
import shlex
import shutil
import subprocess
import sys
from pathlib import Path
from tempfile import TemporaryDirectory
from typing import Any
from clan_cli.errors import ClanError
from ..dirs import get_clan_flake_toplevel
from ..nix import nix_build
from ..dirs import get_clan_flake_toplevel, module_root
from ..nix import nix_build, nix_config
from .folders import sops_secrets_folder
from .machines import add_machine, has_machine
from .secrets import encrypt_secret, has_secret
from .sops import generate_private_key
def generate_secrets(machine: str) -> None:
clan_dir = get_clan_flake_toplevel().as_posix().strip()
env = os.environ.copy()
env["CLAN_DIR"] = clan_dir
env["PYTHONPATH"] = str(module_root().parent)
config = nix_config()
system = config["system"]
proc = subprocess.run(
nix_build(
[
f'path:{clan_dir}#nixosConfigurations."{machine}".config.system.clan.generateSecrets'
]
),
capture_output=True,
text=True,
cmd = nix_build(
[
f'path:{clan_dir}#nixosConfigurations."{machine}".config.system.clan.{system}.generateSecrets'
]
)
proc = subprocess.run(cmd, stdout=subprocess.PIPE, text=True)
if proc.returncode != 0:
print(proc.stderr, file=sys.stderr)
raise ClanError(f"failed to generate secrets:\n{proc.stderr}")
raise ClanError(
f"failed to generate secrets:\n{shlex.join(cmd)}\nexited with {proc.returncode}"
)
secret_generator_script = proc.stdout.strip()
print(secret_generator_script)
@@ -40,6 +50,87 @@ def generate_secrets(machine: str) -> None:
print("successfully generated secrets")
def generate_host_key(machine_name: str) -> None:
if has_machine(machine_name):
return
priv_key, pub_key = generate_private_key()
encrypt_secret(sops_secrets_folder() / f"{machine_name}-age.key", priv_key)
add_machine(machine_name, pub_key, False)
def generate_secrets_group(
secret_group: str, machine_name: str, tempdir: Path, secret_options: dict[str, Any]
) -> None:
clan_dir = get_clan_flake_toplevel()
secrets = secret_options["secrets"]
needs_regeneration = any(
not has_secret(f"{machine_name}-{secret['name']}")
for secret in secrets.values()
)
generator = secret_options["generator"]
subdir = tempdir / secret_group
if needs_regeneration:
facts_dir = subdir / "facts"
facts_dir.mkdir(parents=True)
secrets_dir = subdir / "secrets"
secrets_dir.mkdir(parents=True)
text = f"""\
set -euo pipefail
facts={shlex.quote(str(facts_dir))}
secrets={shlex.quote(str(secrets_dir))}
{generator}
"""
try:
subprocess.run(["bash", "-c", text], check=True)
except subprocess.CalledProcessError:
msg = "failed to the following command:\n"
msg += text
raise ClanError(msg)
for secret in secrets.values():
secret_file = secrets_dir / secret["name"]
if not secret_file.is_file():
msg = f"did not generate a file for '{secret['name']}' when running the following command:\n"
msg += text
raise ClanError(msg)
encrypt_secret(
sops_secrets_folder() / f"{machine_name}-{secret['name']}",
secret_file.read_text(),
)
for fact in secret_options["facts"].values():
fact_file = facts_dir / fact["name"]
if not fact_file.is_file():
msg = f"did not generate a file for '{fact['name']}' when running the following command:\n"
msg += text
raise ClanError(msg)
fact_path = clan_dir.joinpath(fact["path"])
fact_path.parent.mkdir(parents=True, exist_ok=True)
shutil.copyfile(fact_file, fact_path)
# this is called by the sops.nix clan core module
def generate_secrets_from_nix(
machine_name: str,
secret_submodules: dict[str, Any],
) -> None:
generate_host_key(machine_name)
errors = {}
with TemporaryDirectory() as d:
# if any of the secrets are missing, we regenerate all connected facts/secrets
for secret_group, secret_options in secret_submodules.items():
try:
generate_secrets_group(
secret_group, machine_name, Path(d), secret_options
)
except ClanError as e:
errors[secret_group] = e
for secret_group, error in errors.items():
print(f"failed to generate secrets for {machine_name}/{secret_group}:")
print(error, file=sys.stderr)
if len(errors) > 0:
sys.exit(1)
def generate_command(args: argparse.Namespace) -> None:
generate_secrets(args.machine)

View File

@@ -1,20 +1,25 @@
import argparse
import json
import subprocess
from clan_cli.errors import ClanError
import sys
from pathlib import Path
from ..dirs import get_clan_flake_toplevel
from ..nix import nix_build, nix_eval
from ..errors import ClanError
from ..nix import nix_build, nix_config, nix_eval
from ..ssh import parse_deployment_address
from .secrets import decrypt_secret, has_secret
def upload_secrets(machine: str) -> None:
clan_dir = get_clan_flake_toplevel().as_posix()
config = nix_config()
system = config["system"]
proc = subprocess.run(
nix_build(
[
f'{clan_dir}#nixosConfigurations."{machine}".config.system.clan.uploadSecrets'
f'{clan_dir}#nixosConfigurations."{machine}".config.system.clan.{system}.uploadSecrets'
]
),
stdout=subprocess.PIPE,
@@ -48,6 +53,34 @@ def upload_secrets(machine: str) -> None:
print("successfully uploaded secrets")
# this is called by the sops.nix clan core module
def upload_age_key_from_nix(
machine_name: str, deployment_address: str, age_key_file: str
) -> None:
secret_name = f"{machine_name}-age.key"
if not has_secret(secret_name): # skip uploading the secret, not managed by us
return
secret = decrypt_secret(secret_name)
h = parse_deployment_address(machine_name, deployment_address)
path = Path(age_key_file)
proc = h.run(
[
"bash",
"-c",
'mkdir -p "$0" && echo -n "$1" > "$2"',
str(path.parent),
secret,
age_key_file,
],
check=False,
)
if proc.returncode != 0:
print(f"failed to upload age key to {deployment_address}")
sys.exit(1)
def upload_command(args: argparse.Namespace) -> None:
upload_secrets(args.machine)

View File

@@ -11,6 +11,17 @@
machines = {
vm1 = { modulesPath, ... }: {
imports = [ "${toString modulesPath}/virtualisation/qemu-vm.nix" ];
clan.networking.deploymentAddress = "__CLAN_DEPLOYMENT_ADDRESS__";
sops.age.keyFile = "__CLAN_SOPS_KEY_PATH__";
clanCore.secrets.testpassword = {
generator = ''
echo "secret1" > "$secrets/secret1"
echo "fact1" > "$facts/fact1"
'';
secrets.secret1 = { };
facts.fact1 = { };
};
};
};
};

View File

@@ -0,0 +1,38 @@
from pathlib import Path
from typing import TYPE_CHECKING
import pytest
from cli import Cli
from clan_cli.machines.facts import machine_get_fact
from clan_cli.secrets.folders import sops_secrets_folder
from clan_cli.secrets.secrets import has_secret
if TYPE_CHECKING:
from age_keys import KeyPair
@pytest.mark.impure
def test_upload_secret(
monkeypatch: pytest.MonkeyPatch,
test_flake_with_core: Path,
age_keys: list["KeyPair"],
) -> None:
monkeypatch.chdir(test_flake_with_core)
monkeypatch.setenv("SOPS_AGE_KEY", age_keys[0].privkey)
cli = Cli()
cli.run(["secrets", "users", "add", "user1", age_keys[0].pubkey])
cli.run(["secrets", "generate", "vm1"])
has_secret("vm1-age.key")
has_secret("vm1-secret1")
fact1 = machine_get_fact("vm1", "fact1")
assert fact1 == "fact1\n"
age_key = sops_secrets_folder().joinpath("vm1-age.key").joinpath("secret")
secret1 = sops_secrets_folder().joinpath("vm1-secret1").joinpath("secret")
age_key_mtime = age_key.lstat().st_mtime_ns
secret1_mtime = secret1.lstat().st_mtime_ns
# test idempotency
cli.run(["secrets", "generate", "vm1"])
assert age_key.lstat().st_mtime_ns == age_key_mtime
assert secret1.lstat().st_mtime_ns == secret1_mtime

View File

@@ -0,0 +1,40 @@
from pathlib import Path
from typing import TYPE_CHECKING
import pytest
from cli import Cli
from clan_cli.ssh import HostGroup
if TYPE_CHECKING:
from age_keys import KeyPair
@pytest.mark.impure
def test_upload_secret(
monkeypatch: pytest.MonkeyPatch,
test_flake_with_core: Path,
host_group: HostGroup,
age_keys: list["KeyPair"],
) -> None:
monkeypatch.chdir(test_flake_with_core)
monkeypatch.setenv("SOPS_AGE_KEY", age_keys[0].privkey)
cli = Cli()
cli.run(["secrets", "users", "add", "user1", age_keys[0].pubkey])
cli.run(["secrets", "machines", "add", "vm1", age_keys[1].pubkey])
monkeypatch.setenv("SOPS_NIX_SECRET", age_keys[0].privkey)
cli.run(["secrets", "set", "vm1-age.key"])
flake = test_flake_with_core.joinpath("flake.nix")
host = host_group.hosts[0]
addr = f"{host.user}@{host.host}:{host.port}?StrictHostKeyChecking=no&UserKnownHostsFile=/dev/null&IdentityFile={host.key}"
new_text = flake.read_text().replace("__CLAN_DEPLOYMENT_ADDRESS__", addr)
sops_key = test_flake_with_core.joinpath("sops.key")
new_text = new_text.replace("__CLAN_SOPS_KEY_PATH__", str(sops_key))
flake.write_text(new_text)
cli.run(["secrets", "upload", "vm1"])
assert sops_key.exists()
assert sops_key.read_text() == age_keys[0].privkey