Files
Borealis-Github-Replica/Data/Server/Modules/crypto/signing.py
2025-10-19 07:21:28 -06:00

126 lines
4.2 KiB
Python

"""
Code-signing helpers for delivering scripts to agents.
"""
from __future__ import annotations
from pathlib import Path
from typing import Tuple
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.primitives.asymmetric import ed25519
from Modules.runtime import (
ensure_server_certificates_dir,
server_certificates_path,
runtime_path,
)
from .keys import base64_from_spki_der
_KEY_DIR = server_certificates_path("Code-Signing")
_SIGNING_KEY_FILE = _KEY_DIR / "borealis-script-ed25519.key"
_SIGNING_PUB_FILE = _KEY_DIR / "borealis-script-ed25519.pub"
_LEGACY_KEY_FILE = runtime_path("keys") / "borealis-script-ed25519.key"
_LEGACY_PUB_FILE = runtime_path("keys") / "borealis-script-ed25519.pub"
_OLD_RUNTIME_KEY_DIR = runtime_path("script_signing_keys")
_OLD_RUNTIME_KEY_FILE = _OLD_RUNTIME_KEY_DIR / "borealis-script-ed25519.key"
_OLD_RUNTIME_PUB_FILE = _OLD_RUNTIME_KEY_DIR / "borealis-script-ed25519.pub"
class ScriptSigner:
def __init__(self, private_key: ed25519.Ed25519PrivateKey):
self._private = private_key
self._public = private_key.public_key()
def sign(self, payload: bytes) -> bytes:
return self._private.sign(payload)
def public_spki_der(self) -> bytes:
return self._public.public_bytes(
encoding=serialization.Encoding.DER,
format=serialization.PublicFormat.SubjectPublicKeyInfo,
)
def public_base64_spki(self) -> str:
return base64_from_spki_der(self.public_spki_der())
def load_signer() -> ScriptSigner:
private_key = _load_or_create()
return ScriptSigner(private_key)
def _load_or_create() -> ed25519.Ed25519PrivateKey:
ensure_server_certificates_dir("Code-Signing")
_migrate_legacy_material_if_present()
if _SIGNING_KEY_FILE.exists():
with _SIGNING_KEY_FILE.open("rb") as fh:
return serialization.load_pem_private_key(fh.read(), password=None)
if _LEGACY_KEY_FILE.exists():
with _LEGACY_KEY_FILE.open("rb") as fh:
return serialization.load_pem_private_key(fh.read(), password=None)
private_key = ed25519.Ed25519PrivateKey.generate()
pem = private_key.private_bytes(
encoding=serialization.Encoding.PEM,
format=serialization.PrivateFormat.PKCS8,
encryption_algorithm=serialization.NoEncryption(),
)
with _SIGNING_KEY_FILE.open("wb") as fh:
fh.write(pem)
try:
if hasattr(_SIGNING_KEY_FILE, "chmod"):
_SIGNING_KEY_FILE.chmod(0o600)
except Exception:
pass
pub_der = private_key.public_key().public_bytes(
encoding=serialization.Encoding.DER,
format=serialization.PublicFormat.SubjectPublicKeyInfo,
)
_SIGNING_PUB_FILE.write_bytes(pub_der)
return private_key
def _migrate_legacy_material_if_present() -> None:
if _SIGNING_KEY_FILE.exists():
return
# First migrate from legacy runtime path embedded in Server runtime.
try:
if _OLD_RUNTIME_KEY_FILE.exists() and not _SIGNING_KEY_FILE.exists():
ensure_server_certificates_dir("Code-Signing")
try:
_OLD_RUNTIME_KEY_FILE.replace(_SIGNING_KEY_FILE)
except Exception:
_SIGNING_KEY_FILE.write_bytes(_OLD_RUNTIME_KEY_FILE.read_bytes())
if _OLD_RUNTIME_PUB_FILE.exists() and not _SIGNING_PUB_FILE.exists():
try:
_OLD_RUNTIME_PUB_FILE.replace(_SIGNING_PUB_FILE)
except Exception:
_SIGNING_PUB_FILE.write_bytes(_OLD_RUNTIME_PUB_FILE.read_bytes())
except Exception:
pass
if not _LEGACY_KEY_FILE.exists() or _SIGNING_KEY_FILE.exists():
return
try:
ensure_server_certificates_dir("Code-Signing")
try:
_LEGACY_KEY_FILE.replace(_SIGNING_KEY_FILE)
except Exception:
_SIGNING_KEY_FILE.write_bytes(_LEGACY_KEY_FILE.read_bytes())
if _LEGACY_PUB_FILE.exists() and not _SIGNING_PUB_FILE.exists():
try:
_LEGACY_PUB_FILE.replace(_SIGNING_PUB_FILE)
except Exception:
_SIGNING_PUB_FILE.write_bytes(_LEGACY_PUB_FILE.read_bytes())
except Exception:
return