mcuboot/scripts/imgtool/main.py

450 lines
17 KiB
Python
Executable File

#! /usr/bin/env python3
#
# Copyright 2017-2020 Linaro Limited
# Copyright 2019-2021 Arm Limited
#
# SPDX-License-Identifier: Apache-2.0
#
# 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 re
import click
import getpass
import imgtool.keys as keys
import sys
import base64
from imgtool import image, imgtool_version
from imgtool.version import decode_version
from .keys import (
RSAUsageError, ECDSAUsageError, Ed25519UsageError, X25519UsageError)
MIN_PYTHON_VERSION = (3, 6)
if sys.version_info < MIN_PYTHON_VERSION:
sys.exit("Python %s.%s or newer is required by imgtool."
% MIN_PYTHON_VERSION)
def gen_rsa2048(keyfile, passwd):
keys.RSA.generate().export_private(path=keyfile, passwd=passwd)
def gen_rsa3072(keyfile, passwd):
keys.RSA.generate(key_size=3072).export_private(path=keyfile,
passwd=passwd)
def gen_ecdsa_p256(keyfile, passwd):
keys.ECDSA256P1.generate().export_private(keyfile, passwd=passwd)
def gen_ecdsa_p224(keyfile, passwd):
print("TODO: p-224 not yet implemented")
def gen_ed25519(keyfile, passwd):
keys.Ed25519.generate().export_private(path=keyfile, passwd=passwd)
def gen_x25519(keyfile, passwd):
keys.X25519.generate().export_private(path=keyfile, passwd=passwd)
valid_langs = ['c', 'rust']
keygens = {
'rsa-2048': gen_rsa2048,
'rsa-3072': gen_rsa3072,
'ecdsa-p256': gen_ecdsa_p256,
'ecdsa-p224': gen_ecdsa_p224,
'ed25519': gen_ed25519,
'x25519': gen_x25519,
}
def load_signature(sigfile):
with open(sigfile, 'rb') as f:
signature = base64.b64decode(f.read())
return signature
def save_signature(sigfile, sig):
with open(sigfile, 'wb') as f:
signature = base64.b64encode(sig)
f.write(signature)
def load_key(keyfile):
# TODO: better handling of invalid pass-phrase
key = keys.load(keyfile)
if key is not None:
return key
passwd = getpass.getpass("Enter key passphrase: ").encode('utf-8')
return keys.load(keyfile, passwd)
def get_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')
@click.option('-p', '--password', is_flag=True,
help='Prompt for password to protect key')
@click.option('-t', '--type', metavar='type', required=True,
type=click.Choice(keygens.keys()), prompt=True,
help='{}'.format('One of: {}'.format(', '.join(keygens.keys()))))
@click.option('-k', '--key', metavar='filename', required=True)
@click.command(help='Generate pub/private keypair')
def keygen(type, key, password):
password = get_password() if password else None
keygens[type](key, password)
@click.option('-l', '--lang', metavar='lang', default=valid_langs[0],
type=click.Choice(valid_langs))
@click.option('-k', '--key', metavar='filename', required=True)
@click.command(help='Dump public key from keypair')
def getpub(key, lang):
key = load_key(key)
if key is None:
print("Invalid passphrase")
elif lang == 'c':
key.emit_c_public()
elif lang == 'rust':
key.emit_rust_public()
else:
raise ValueError("BUG: should never get here!")
@click.option('--minimal', default=False, is_flag=True,
help='Reduce the size of the dumped private key to include only '
'the minimum amount of data required to decrypt. This '
'might require changes to the build config. Check the docs!'
)
@click.option('-k', '--key', metavar='filename', required=True)
@click.command(help='Dump private key from keypair')
def getpriv(key, minimal):
key = load_key(key)
if key is None:
print("Invalid passphrase")
try:
key.emit_private(minimal)
except (RSAUsageError, ECDSAUsageError, Ed25519UsageError,
X25519UsageError) as e:
raise click.UsageError(e)
@click.argument('imgfile')
@click.option('-k', '--key', metavar='filename')
@click.command(help="Check that signed image can be verified by given key")
def verify(key, imgfile):
key = load_key(key) if key else None
ret, version, digest = image.Image.verify(imgfile, key)
if ret == image.VerifyResult.OK:
print("Image was correctly validated")
print("Image version: {}.{}.{}+{}".format(*version))
print("Image digest: {}".format(digest.hex()))
return
elif ret == image.VerifyResult.INVALID_MAGIC:
print("Invalid image magic; is this an MCUboot image?")
elif ret == image.VerifyResult.INVALID_TLV_INFO_MAGIC:
print("Invalid TLV info magic; is this an MCUboot image?")
elif ret == image.VerifyResult.INVALID_HASH:
print("Image has an invalid sha256 digest")
elif ret == image.VerifyResult.INVALID_SIGNATURE:
print("No signature found for the given key")
else:
print("Unknown return code: {}".format(ret))
sys.exit(1)
def validate_version(ctx, param, value):
try:
decode_version(value)
return value
except ValueError as e:
raise click.BadParameter("{}".format(e))
def validate_security_counter(ctx, param, value):
if value is not None:
if value.lower() == 'auto':
return 'auto'
else:
try:
return int(value, 0)
except ValueError:
raise click.BadParameter(
"{} is not a valid integer. Please use code literals "
"prefixed with 0b/0B, 0o/0O, or 0x/0X as necessary."
.format(value))
def validate_header_size(ctx, param, value):
min_hdr_size = image.IMAGE_HEADER_SIZE
if value < min_hdr_size:
raise click.BadParameter(
"Minimum value for -H/--header-size is {}".format(min_hdr_size))
return value
def get_dependencies(ctx, param, value):
if value is not None:
versions = []
images = re.findall(r"\((\d+)", value)
if len(images) == 0:
raise click.BadParameter(
"Image dependency format is invalid: {}".format(value))
raw_versions = re.findall(r",\s*([0-9.+]+)\)", value)
if len(images) != len(raw_versions):
raise click.BadParameter(
'''There's a mismatch between the number of dependency images
and versions in: {}'''.format(value))
for raw_version in raw_versions:
try:
versions.append(decode_version(raw_version))
except ValueError as e:
raise click.BadParameter("{}".format(e))
dependencies = dict()
dependencies[image.DEP_IMAGES_KEY] = images
dependencies[image.DEP_VERSIONS_KEY] = versions
return dependencies
class BasedIntParamType(click.ParamType):
name = 'integer'
def convert(self, value, param, ctx):
try:
return int(value, 0)
except ValueError:
self.fail('%s is not a valid integer. Please use code literals '
'prefixed with 0b/0B, 0o/0O, or 0x/0X as necessary.'
% value, param, ctx)
@click.argument('outfile')
@click.argument('infile')
@click.option('--custom-tlv', required=False, nargs=2, default=[],
multiple=True, metavar='[tag] [value]',
help='Custom TLV that will be placed into protected area. '
'Add "0x" prefix if the value should be interpreted as an '
'integer, otherwise it will be interpreted as a string. '
'Specify the option multiple times to add multiple TLVs.')
@click.option('-R', '--erased-val', type=click.Choice(['0', '0xff']),
required=False,
help='The value that is read back from erased flash.')
@click.option('-x', '--hex-addr', type=BasedIntParamType(), required=False,
help='Adjust address in hex output file.')
@click.option('-L', '--load-addr', type=BasedIntParamType(), required=False,
help='Load address for image when it should run from RAM.')
@click.option('-F', '--rom-fixed', type=BasedIntParamType(), required=False,
help='Set flash address the image is built for.')
@click.option('--save-enctlv', default=False, is_flag=True,
help='When upgrading, save encrypted key TLVs instead of plain '
'keys. Enable when BOOT_SWAP_SAVE_ENCTLV config option '
'was set.')
@click.option('-E', '--encrypt', metavar='filename',
help='Encrypt image using the provided public key. '
'(Not supported in direct-xip or ram-load mode.)')
@click.option('--encrypt-keylen', default='128',
type=click.Choice(['128','256']),
help='When encrypting the image using AES, select a 128 bit or '
'256 bit key len.')
@click.option('-c', '--clear', required=False, is_flag=True, default=False,
help='Output a non-encrypted image with encryption capabilities,'
'so it can be installed in the primary slot, and encrypted '
'when swapped to the secondary.')
@click.option('-e', '--endian', type=click.Choice(['little', 'big']),
default='little', help="Select little or big endian")
@click.option('--overwrite-only', default=False, is_flag=True,
help='Use overwrite-only instead of swap upgrades')
@click.option('--boot-record', metavar='sw_type', help='Create CBOR encoded '
'boot record TLV. The sw_type represents the role of the '
'software component (e.g. CoFM for coprocessor firmware). '
'[max. 12 characters]')
@click.option('-M', '--max-sectors', type=int,
help='When padding allow for this amount of sectors (defaults '
'to 128)')
@click.option('--confirm', default=False, is_flag=True,
help='When padding the image, mark it as confirmed (implies '
'--pad)')
@click.option('--pad', default=False, is_flag=True,
help='Pad image to --slot-size bytes, adding trailer magic')
@click.option('-S', '--slot-size', type=BasedIntParamType(), required=True,
help='Size of the slot. If the slots have different sizes, use '
'the size of the secondary slot.')
@click.option('--pad-header', default=False, is_flag=True,
help='Add --header-size zeroed bytes at the beginning of the '
'image')
@click.option('-H', '--header-size', callback=validate_header_size,
type=BasedIntParamType(), required=True)
@click.option('--pad-sig', default=False, is_flag=True,
help='Add 0-2 bytes of padding to ECDSA signature '
'(for mcuboot <1.5)')
@click.option('-d', '--dependencies', callback=get_dependencies,
required=False, help='''Add dependence on another image, format:
"(<image_ID>,<image_version>), ... "''')
@click.option('-s', '--security-counter', callback=validate_security_counter,
help='Specify the value of security counter. Use the `auto` '
'keyword to automatically generate it from the image version.')
@click.option('-v', '--version', callback=validate_version, required=True)
@click.option('--align', type=click.Choice(['1', '2', '4', '8', '16', '32']),
required=True)
@click.option('--max-align', type=click.Choice(['8', '16', '32']),
required=False,
help='Maximum flash alignment. Set if flash alignment of the '
'primary and secondary slot differ and any of them is larger '
'than 8.')
@click.option('--public-key-format', type=click.Choice(['hash', 'full']),
default='hash', help='In what format to add the public key to '
'the image manifest: full key or hash of the key.')
@click.option('-k', '--key', metavar='filename')
@click.option('--fix-sig', metavar='filename',
help='fixed signature for the image. It will be used instead of'
'the signature calculated using the public key')
@click.option('--fix-sig-pubkey', metavar='filename',
help='public key relevant to fixed signature')
@click.option('--sig-out', metavar='filename',
help='Path to the file to which signature will be written'
'The image signature will be encoded as base64 formatted string')
@click.option('--vector-to-sign', type=click.Choice(['payload', 'digest']),
help='send to OUTFILE the payload or payload''s digest instead of'
'complied image. These data can be used for external image'
'signing')
@click.command(help='''Create a signed or unsigned image\n
INFILE and OUTFILE are parsed as Intel HEX if the params have
.hex extension, otherwise binary format is used''')
def sign(key, public_key_format, align, version, pad_sig, header_size,
pad_header, slot_size, pad, confirm, max_sectors, overwrite_only,
endian, encrypt_keylen, encrypt, infile, outfile, dependencies,
load_addr, hex_addr, erased_val, save_enctlv, security_counter,
boot_record, custom_tlv, rom_fixed, max_align, clear, fix_sig,
fix_sig_pubkey, sig_out, vector_to_sign):
if confirm:
# Confirmed but non-padded images don't make much sense, because
# otherwise there's no trailer area for writing the confirmed status.
pad = True
img = image.Image(version=decode_version(version), header_size=header_size,
pad_header=pad_header, pad=pad, confirm=confirm,
align=int(align), slot_size=slot_size,
max_sectors=max_sectors, overwrite_only=overwrite_only,
endian=endian, load_addr=load_addr, rom_fixed=rom_fixed,
erased_val=erased_val, save_enctlv=save_enctlv,
security_counter=security_counter, max_align=max_align)
img.load(infile)
key = load_key(key) if key else None
enckey = load_key(encrypt) if encrypt else None
if enckey and key:
if ((isinstance(key, keys.ECDSA256P1) and
not isinstance(enckey, keys.ECDSA256P1Public))
or (isinstance(key, keys.RSA) and
not isinstance(enckey, keys.RSAPublic))):
# FIXME
raise click.UsageError("Signing and encryption must use the same "
"type of key")
if pad_sig and hasattr(key, 'pad_sig'):
key.pad_sig = True
# Get list of custom protected TLVs from the command-line
custom_tlvs = {}
for tlv in custom_tlv:
tag = int(tlv[0], 0)
if tag in custom_tlvs:
raise click.UsageError('Custom TLV %s already exists.' % hex(tag))
if tag in image.TLV_VALUES.values():
raise click.UsageError(
'Custom TLV %s conflicts with predefined TLV.' % hex(tag))
value = tlv[1]
if value.startswith('0x'):
if len(value[2:]) % 2:
raise click.UsageError('Custom TLV length is odd.')
custom_tlvs[tag] = bytes.fromhex(value[2:])
else:
custom_tlvs[tag] = value.encode('utf-8')
# Allow signature calculated externally.
raw_signature = load_signature(fix_sig) if fix_sig else None
baked_signature = None
pub_key = None
if raw_signature is not None:
if fix_sig_pubkey is None:
raise click.UsageError(
'public key of the fixed signature is not specified')
pub_key = load_key(fix_sig_pubkey)
baked_signature = {
'value' : raw_signature
}
img.create(key, public_key_format, enckey, dependencies, boot_record,
custom_tlvs, int(encrypt_keylen), clear, baked_signature, pub_key,
vector_to_sign)
img.save(outfile, hex_addr)
if sig_out is not None:
new_signature = img.get_signature()
save_signature(sig_out, new_signature)
class AliasesGroup(click.Group):
_aliases = {
"create": "sign",
}
def list_commands(self, ctx):
cmds = [k for k in self.commands]
aliases = [k for k in self._aliases]
return sorted(cmds + aliases)
def get_command(self, ctx, cmd_name):
rv = click.Group.get_command(self, ctx, cmd_name)
if rv is not None:
return rv
if cmd_name in self._aliases:
return click.Group.get_command(self, ctx, self._aliases[cmd_name])
return None
@click.command(help='Print imgtool version information')
def version():
print(imgtool_version)
@click.command(cls=AliasesGroup,
context_settings=dict(help_option_names=['-h', '--help']))
def imgtool():
pass
imgtool.add_command(keygen)
imgtool.add_command(getpub)
imgtool.add_command(getpriv)
imgtool.add_command(verify)
imgtool.add_command(sign)
imgtool.add_command(version)
if __name__ == '__main__':
imgtool()