mcuboot/scripts/imgtool/keys/general.py

116 lines
4.1 KiB
Python

"""General key class."""
# SPDX-License-Identifier: Apache-2.0
import binascii
import io
import os
import sys
from cryptography.hazmat.primitives.hashes import Hash, SHA256
AUTOGEN_MESSAGE = "/* Autogenerated by imgtool.py, do not edit. */"
class FileHandler(object):
def __init__(self, file, *args, **kwargs):
self.file_in = file
self.args = args
self.kwargs = kwargs
def __enter__(self):
if isinstance(self.file_in, (str, bytes, os.PathLike)):
self.file = open(self.file_in, *self.args, **self.kwargs)
else:
self.file = self.file_in
return self.file
def __exit__(self, *args):
if self.file != self.file_in:
self.file.close()
class KeyClass(object):
def _emit(self, header, trailer, encoded_bytes, indent, file=sys.stdout,
len_format=None):
with FileHandler(file, 'w') as file:
self._emit_to_output(header, trailer, encoded_bytes, indent,
file, len_format)
def _emit_to_output(self, header, trailer, encoded_bytes, indent, file,
len_format):
print(AUTOGEN_MESSAGE, file=file)
print(header, end='', file=file)
for count, b in enumerate(encoded_bytes):
if count % 8 == 0:
print("\n" + indent, end='', file=file)
else:
print(" ", end='', file=file)
print("0x{:02x},".format(b), end='', file=file)
print("\n" + trailer, file=file)
if len_format is not None:
print(len_format.format(len(encoded_bytes)), file=file)
def _emit_raw(self, encoded_bytes, file):
with FileHandler(file, 'wb') as file:
try:
# file.buffer is not part of the TextIOBase API
# and may not exist in some implementations.
file.buffer.write(encoded_bytes)
except AttributeError:
# raw binary data, can be for example io.BytesIO
file.write(encoded_bytes)
def emit_c_public(self, file=sys.stdout):
self._emit(
header="const unsigned char {}_pub_key[] = {{"
.format(self.shortname()),
trailer="};",
encoded_bytes=self.get_public_bytes(),
indent=" ",
len_format="const unsigned int {}_pub_key_len = {{}};"
.format(self.shortname()),
file=file)
def emit_c_public_hash(self, file=sys.stdout):
digest = Hash(SHA256())
digest.update(self.get_public_bytes())
self._emit(
header="const unsigned char {}_pub_key_hash[] = {{"
.format(self.shortname()),
trailer="};",
encoded_bytes=digest.finalize(),
indent=" ",
len_format="const unsigned int {}_pub_key_hash_len = {{}};"
.format(self.shortname()),
file=file)
def emit_raw_public(self, file=sys.stdout):
self._emit_raw(self.get_public_bytes(), file=file)
def emit_raw_public_hash(self, file=sys.stdout):
digest = Hash(SHA256())
digest.update(self.get_public_bytes())
self._emit_raw(digest.finalize(), file=file)
def emit_rust_public(self, file=sys.stdout):
self._emit(
header="static {}_PUB_KEY: &[u8] = &["
.format(self.shortname().upper()),
trailer="];",
encoded_bytes=self.get_public_bytes(),
indent=" ",
file=file)
def emit_public_pem(self, file=sys.stdout):
with FileHandler(file, 'w') as file:
print(str(self.get_public_pem(), 'utf-8'), file=file, end='')
def emit_private(self, minimal, format, file=sys.stdout):
self._emit(
header="const unsigned char enc_priv_key[] = {",
trailer="};",
encoded_bytes=self.get_private_bytes(minimal, format),
indent=" ",
len_format="const unsigned int enc_priv_key_len = {};",
file=file)