mcuboot/scripts/imgtool.py

146 lines
4.6 KiB
Python
Executable File

#! /usr/bin/env python3
#
# Copyright 2017 Linaro Limited
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import argparse
import getpass
from imgtool import keys
from imgtool import image
from imgtool import version
import sys
def get_password(args):
if args.password:
while True:
passwd = getpass.getpass("Enter key passphrase: ")
passwd2 = getpass.getpass("Reenter passphrase: ")
if passwd == passwd2:
break
print("Passwords do not match, try again")
# Password must be bytes, always use UTF-8 for consistent
# encoding.
return passwd.encode('utf-8')
else:
return None
def gen_rsa2048(args):
passwd = get_password(args)
keys.RSA2048.generate().export_private(path=args.key, passwd=passwd)
def gen_ecdsa_p256(args):
passwd = get_password(args)
keys.ECDSA256P1.generate().export_private(args.key, passwd=passwd)
def gen_ecdsa_p224(args):
print("TODO: p-224 not yet implemented")
keygens = {
'rsa-2048': gen_rsa2048,
'ecdsa-p256': gen_ecdsa_p256,
'ecdsa-p224': gen_ecdsa_p224, }
def do_keygen(args):
if args.type not in keygens:
msg = "Unexpected key type: {}".format(args.type)
raise argparse.ArgumentTypeError(msg)
keygens[args.type](args)
def load_key(args):
key = keys.load(args.key)
if key is not None:
return key
passwd = getpass.getpass("Enter key passphrase: ")
passwd = passwd.encode('utf-8')
return keys.load(args.key, passwd)
def do_getpub(args):
key = load_key(args)
if args.lang == 'c':
key.emit_c()
elif args.lang == 'rust':
key.emit_rust()
else:
msg = "Unsupported language, valid are: c, or rust"
raise argparse.ArgumentTypeError(msg)
def do_sign(args):
img = image.Image.load(args.infile, version=args.version,
header_size=args.header_size,
included_header=args.included_header,
pad=args.pad)
key = load_key(args) if args.key else None
img.sign(key)
if args.pad:
img.pad_to(args.pad, args.align)
img.save(args.outfile)
subcmds = {
'keygen': do_keygen,
'getpub': do_getpub,
'sign': do_sign, }
def alignment_value(text):
value = int(text)
if value not in [1, 2, 4, 8]:
msg = "{} must be one of 1, 2, 4 or 8".format(value)
raise argparse.ArgumentTypeError(msg)
return value
def intparse(text):
"""Parse a command line argument as an integer.
Accepts 0x and other prefixes to allow other bases to be used."""
return int(text, 0)
def args():
parser = argparse.ArgumentParser()
subs = parser.add_subparsers(help='subcommand help', dest='subcmd')
keygenp = subs.add_parser('keygen', help='Generate pub/private keypair')
keygenp.add_argument('-k', '--key', metavar='filename', required=True)
keygenp.add_argument('-t', '--type', metavar='type',
choices=keygens.keys(), required=True)
keygenp.add_argument('-p', '--password', default=False, action='store_true',
help='Prompt for password to protect key')
getpub = subs.add_parser('getpub', help='Get public key from keypair')
getpub.add_argument('-k', '--key', metavar='filename', required=True)
getpub.add_argument('-l', '--lang', metavar='lang', default='c')
sign = subs.add_parser('sign', help='Sign an image with a private key')
sign.add_argument('-k', '--key', metavar='filename')
sign.add_argument("--align", type=alignment_value, required=True)
sign.add_argument("-v", "--version", type=version.decode_version, required=True)
sign.add_argument("-H", "--header-size", type=intparse, required=True)
sign.add_argument("--included-header", default=False, action='store_true',
help='Image has gap for header')
sign.add_argument("--pad", type=intparse,
help='Pad image to this many bytes, adding trailer magic')
sign.add_argument("infile")
sign.add_argument("outfile")
args = parser.parse_args()
if args.subcmd is None:
print('Must specify a subcommand', file=sys.stderr)
sys.exit(1)
subcmds[args.subcmd](args)
if __name__ == '__main__':
args()