esp-idf/examples/protocols/mqtt/ssl_ds/configure_ds.py

315 lines
10 KiB
Python

#!/usr/bin/env python
# Copyright 2020 Espressif Systems (Shanghai) Co., Ltd.
# 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 os
import sys
import hashlib
import hmac
import struct
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.primitives.asymmetric import rsa
from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.utils import int_to_bytes
try:
import esptool
import espefuse
except ImportError:
idf_path = os.getenv("IDF_PATH")
if not idf_path or not os.path.exists(idf_path):
raise Exception("IDF_PATH not found")
sys.path.insert(0, os.path.join(idf_path, "components", "esptool_py", "esptool"))
import esptool
import espefuse
try:
import nvs_partition_gen as nvs_gen
except ImportError:
idf_path = os.getenv("IDF_PATH")
if not idf_path or not os.path.exists(idf_path):
raise Exception("IDF_PATH not found")
sys.path.insert(0, os.path.join(idf_path, "components", "nvs_flash", "nvs_partition_generator"))
import nvs_partition_gen as nvs_gen
esp_ds_data_dir = 'esp_ds_data'
# hmac_key_file is generated when HMAC_KEY is calculated, it is used when burning HMAC_KEY to efuse
hmac_key_file = esp_ds_data_dir + '/hmac_key.bin'
# csv and bin filenames are default filenames for nvs partition files created with this script
csv_filename = esp_ds_data_dir + '/pre_prov.csv'
bin_filename = esp_ds_data_dir + '/pre_prov.bin'
def load_privatekey(key_file_path, password=None):
key_file = open(key_file_path, 'rb')
key = key_file.read()
key_file.close()
return serialization.load_pem_private_key(key, password=password, backend=default_backend())
def number_as_bytes(number, pad_bits=None):
"""
Given a number, format as a little endian array of bytes
"""
result = int_to_bytes(number)[::-1]
while pad_bits is not None and len(result) < (pad_bits // 8):
result += b'\x00'
return result
def calculate_ds_parameters(privkey, priv_key_pass):
private_key = load_privatekey(privkey, priv_key_pass)
if not isinstance(private_key, rsa.RSAPrivateKey):
print("Only RSA private keys are supported")
sys.exit(-1)
priv_numbers = private_key.private_numbers()
pub_numbers = private_key.public_key().public_numbers()
Y = priv_numbers.d
M = pub_numbers.n
key_size = private_key.key_size
supported_key_size = [1024, 2048, 3072, 4096]
if key_size not in supported_key_size:
print("Key size not supported, supported sizes are" + str(supported_key_size))
sys.exit(-1)
hmac_key = os.urandom(32)
with open(hmac_key_file, 'wb') as key_file:
key_file.write(hmac_key)
iv = os.urandom(16)
rr = 1 << (key_size * 2)
rinv = rr % pub_numbers.n
mprime = - rsa._modinv(M, 1 << 32)
mprime &= 0xFFFFFFFF
length = key_size // 32 - 1
aes_key = hmac.HMAC(hmac_key, b"\xFF" * 32, hashlib.sha256).digest()
md_in = number_as_bytes(Y, 4096) + \
number_as_bytes(M, 4096) + \
number_as_bytes(rinv, 4096) + \
struct.pack("<II", mprime, length) + \
iv
assert len(md_in) == 12480 / 8
md = hashlib.sha256(md_in).digest()
# Y4096 || M4096 || Rb4096 || M_prime32 || LENGTH32 || MD256 || 0x08*8
p = number_as_bytes(Y, 4096) + \
number_as_bytes(M, 4096) + \
number_as_bytes(rinv, 4096) + \
md + \
struct.pack("<II", mprime, length) + \
b'\x08' * 8
assert len(p) == 12672 / 8
cipher = Cipher(algorithms.AES(aes_key), modes.CBC(iv), backend=default_backend())
encryptor = cipher.encryptor()
c = encryptor.update(p) + encryptor.finalize()
return c, iv, key_size
class DefineArgs(object):
def __init__(self, attributes):
for key, value in attributes.items():
self.__setattr__(key, value)
def efuse_summary(esp,args):
efuses, _efuse_operations = espefuse.get_efuses(esp, esp.CHIP_NAME, False, False, False)
summary_args = DefineArgs({
'baud': 115200,
'before': 'default_reset',
'chip': esp.CHIP_NAME,
'debug': False,
'do_not_confirm': False,
'file': sys.stdout,
'mode':'w',
'encding': 'utf-8',
'format': 'summary',
'operation': 'summary',
'port':args.port,
})
print("\n\n\n\t---SUMMARY START---\n")
espefuse.summary(esp, efuses, summary_args)
print("\n\t---SUMMARY END---\n\n")
def efuse_burn_key(esp, args):
efuses, efuse_operations = espefuse.get_efuses(esp, esp.CHIP_NAME, False, False, False)
if args.efuse_key_id is None:
print("efuse Key id cannot be None")
sys.exit(-1)
key_file = open(hmac_key_file, 'rb')
# First element of _KEYBLOCKS is config data so add offset of 1
key_block = efuses._KEYBLOCKS[args.efuse_key_id + 1][0]
burn_key_args = DefineArgs({
'baud': 115200,
'before': 'default_reset',
'chip': esp.CHIP_NAME,
'debug': False,
'do_not_confirm': False,
'block': [key_block],
'keyfile': [key_file],
'keypurpose': ['HMAC_DOWN_DIGITAL_SIGNATURE'],
'operation': 'burn_key',
'force_write_always': False,
'no_read_protect': True,
'no_write_protect': False,
'port': args.port,
})
try:
efuse_operations.burn_key(esp, efuses, burn_key_args, None)
key_file.close()
except esptool.FatalError:
print("\nERROR: The provided key block already contains previously burned key, please use a different key block ID")
sys.exit(-1)
def generate_csv_file(c, iv, hmac_key_id, key_size, csv_file):
with open(csv_file, 'wt', encoding='utf8') as f:
f.write("# This is a generated csv file containing required parameters for the Digital Signature operaiton\n")
f.write("key,type,encoding,value\nesp_ds_ns,namespace,,\n")
f.write("esp_ds_c,data,hex2bin,%s\n" % (c.hex()))
f.write("esp_ds_iv,data,hex2bin,%s\n" % (iv.hex()))
f.write("esp_ds_key_id,data,u8,%d\n" % (hmac_key_id))
f.write("esp_ds_rsa_len,data,u16,%d\n" % (key_size))
def generate_nvs_partition(input_filename, output_filename):
nvs_args = DefineArgs({
'input': input_filename,
'outdir': os.getcwd(),
'output': output_filename,
'size': hex(0x3000),
'version': 2,
'keyfile':None,
})
nvs_gen.generate(nvs_args, is_encr_enabled=False, encr_key=None)
def flash_nvs_partition(bin_path, addr, esp):
esp.connect()
print(bin_path)
abs_bin_path = os.path.dirname(os.path.abspath(__file__)) + '/' + bin_path
print(abs_bin_path)
if (os.path.exists(abs_bin_path) is False):
print("NVS partition not found")
sys.exit(-1)
with open(bin_path, 'rb') as nvs_file:
flash_file = [(addr, nvs_file)]
flash_args = DefineArgs({
'flash_size': '4MB',
'flash_mode': 'qio',
'flash_freq': '80m',
'addr_filename': flash_file,
'no_stub': False,
'compress': False,
'verify': False,
'encrypt': False,
'erase_all': False,
})
esp.change_baud(baud=921600)
esptool.write_flash(esp, flash_args)
def main():
parser = argparse.ArgumentParser(description='''Provision the ESPWROOM32SE device with
device_certificate and signer_certificate required for TLS authentication''')
parser.add_argument(
'--private-key',
dest='privkey',
default='main/client.key',
metavar='relative/path/to/client-priv-key',
help='relative path(from secure_cert_mfg.py) to signer certificate private key')
parser.add_argument(
"--pwd", '--password',
dest='priv_key_pass',
metavar='[password]',
help='the password associated with the private key')
parser.add_argument(
'--summary',
dest='summary',action='store_true',
help='Provide this option to print efuse summary the chip')
parser.add_argument(
'--efuse_key_id',
dest='efuse_key_id', type=int, choices=range(1,6),
metavar='[key_id] ',
default=1,
help='Provide the efuse key_id which contains/will contain HMAC_KEY, default is 1')
parser.add_argument(
"--port", '-p',
dest='port',
metavar='[port]',
required=True,
help='UART com port to which ESP device is connected')
parser.add_argument(
'--overwrite',
dest='overwrite', action='store_true',
help='Overwrite previously generated keys')
args = parser.parse_args()
esp = esptool.ESPLoader.detect_chip(args.port,baud=115200)
if (esp.CHIP_NAME != 'ESP32-S2'):
print("Only ESP32S2 chip is supported")
sys.exit(-1)
if args.summary is not False:
efuse_summary(esp, args)
sys.exit(0)
if (os.path.exists(esp_ds_data_dir) is False):
os.makedirs(esp_ds_data_dir)
else:
if (args.overwrite is False):
print("WARNING: previous ecrypted private key data exists.\nIf you want to overwrite,"
" please execute your command with providing \"--overwrite\" option")
sys.exit(0)
else:
print("overwriting previous encrypted private key data, as you have provided \"--overwrite\" option")
c, iv, key_size = calculate_ds_parameters(args.privkey, args.priv_key_pass)
efuse_burn_key(esp, args)
generate_csv_file(c, iv, args.efuse_key_id, key_size, csv_filename)
generate_nvs_partition(csv_filename, bin_filename)
flash_nvs_partition(bin_filename, 0x10000, esp)
if __name__ == "__main__":
main()