diff options
Diffstat (limited to 'controller/fw/tools/presig_gen.py')
| -rw-r--r-- | controller/fw/tools/presig_gen.py | 184 |
1 files changed, 91 insertions, 93 deletions
diff --git a/controller/fw/tools/presig_gen.py b/controller/fw/tools/presig_gen.py index 2d97391..ff9dffe 100644 --- a/controller/fw/tools/presig_gen.py +++ b/controller/fw/tools/presig_gen.py @@ -4,19 +4,14 @@ import os import sys import textwrap import uuid -import hashlib +import hmac import binascii -import sqlite3 import time +from datetime import datetime -import nacl.signing -import nacl.encoding - -from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes -from cryptography.hazmat.backends import default_backend - - +LINKING_KEY_SIZE = 16 PRESIG_VERSION = '000.001' +DOMAINS = ['all', 'country', 'region', 'vendor', 'series'] def format_hex(data, indent=4, wrap=True): indent = ' '*indent @@ -28,48 +23,47 @@ def format_hex(data, indent=4, wrap=True): return f'{{\n{par}\n}}' return par -def domain_string(domain_name, value, serial): - return f'smart reset domain string v{PRESIG_VERSION}: domain:{domain_name}={value}@{serial}' +def domain_string(domain, value): + return f'smart reset domain string v{PRESIG_VERSION}: domain:{domain}={value}' -if __name__ == '__main__': - import argparse - parser = argparse.ArgumentParser() - parser.add_argument('keyfile', help='Key file to use') - parser.add_argument('presig_db', nargs='?', help='sqlite3 dbfile for generated presig authorization keys') - parser.add_argument('-g', '--generate', action='store_true', help='Generate signing keypair') - parser.add_argument('-v', '--vendor', type=str, default='Darthenschmidt Cyberei und Verschleierungstechnik GmbH', help='Vendor name for vendor domain') - parser.add_argument('-s', '--series', type=str, default='Frobnicator v0.23.7', help='Series identifier for series domain') - parser.add_argument('-r', '--region', type=str, default='Neuland', help='Region name for region domain') - parser.add_argument('-c', '--country', type=str, default='Germany', help='Country name for country domain') - parser.add_argument('-p', '--start-serial', type=int, default=0, help='First presig serial number to use') - parser.add_argument('-n', '--presig-count', type=int, default=3, help='Number of presigs to generate') - parser.add_argument('-i', '--iv', type=str, default='safety reset oob presig iv', help='IV for presig generation') - args = parser.parse_args() +def keygen_cmd(args): + if os.path.exists(args.keyfile) and not args.force: + print("Error: keyfile already exists. We won't overwrite it. Instead please remove it manually.", + file=sys.stderr) + return 1 + + root_key = os.urandom(LINKING_KEY_SIZE) - if args.generate: - if os.path.exists(args.keyfile): - print("Error: keyfile already exists. We won't overwrite it. Instead please remove it manually.", - file=sys.stderr) - sys.exit(1) - signing_key = nacl.signing.SigningKey.generate() - with open(args.keyfile, 'wb') as f: - f.write(signing_key.encode(encoder=nacl.encoding.Base64Encoder)) - f.write(b'\n') - sys.exit(0) + with open(args.keyfile, 'wb') as f: + f.write(binascii.hexlify(root_key)) + f.write(b'\n') + return 0 +def gen_at_height(domain, value, height, key): + # nanananananana BLOCKCHAIN! + + ds = domain_string(domain, value).encode('utf-8') + + for height in range(height+1): + key = hmac.digest(key, ds, 'sha512')[:LINKING_KEY_SIZE] + + return key + +def auth_cmd(args): with open(args.keyfile, 'r') as f: - signing_key = nacl.signing.SigningKey(f.read().strip(), encoder=nacl.encoding.Base64Encoder) - pubkey_bytes = signing_key.verify_key.encode(encoder=nacl.encoding.RawEncoder) - pubkey_hash = hashlib.sha512(pubkey_bytes).digest()[:16] + root_key = binascii.unhexlify(f.read().strip()) - if not args.presig_db: - print('The presig_db parameter is required.', file=sys.stderr) - sys.exit(1) + vals = [ (domain, getattr(args, domain)) for domain in DOMAINS if getattr(args, domain) is not None ] + if not vals: + vals = [('all', 'all')] + for domain, value in vals: + auth = gen_at_height(domain, value, args.height, root_key) + print(f'{domain}="{value}" @{args.height}: {binascii.hexlify(auth).decode()}') - db = sqlite3.connect(args.presig_db) - db.execute('CREATE TABLE IF NOT EXISTS presig_authkey (timestamp, pubkey_hash, bundle_id, presig_ver, domain, value, serial, authkey)') - bundle_id = uuid.uuid4().bytes +def prekey_cmd(args): + with open(args.keyfile, 'r') as f: + root_key = binascii.unhexlify(f.read().strip()) print('#include <stdint.h>') print('#include <assert.h>') @@ -77,67 +71,71 @@ if __name__ == '__main__': print('#include "crypto.h"') print() + bundle_id = uuid.uuid4().bytes print(f'/* bundle id {binascii.hexlify(bundle_id).decode()} */') print(f'uint8_t presig_bundle_id[16] = {format_hex(bundle_id)};') - print(f'int presig_first_serial = {args.start_serial};') print() - - print(f'uint8_t oob_trigger_pubkey[crypto_sign_PUBLICKEYBYTES] = {format_hex(pubkey_bytes)};') + print(f'/* generated on {datetime.now()} */') + print(f'uint64_t bundle_timestamp = {int(time.time())};') + print() + print(f'int presig_height = {args.max_height};') print() - print('uint8_t presig_messages[_TRIGGER_DOMAIN_COUNT][PRESIG_STORE_SIZE][PRESIG_MSG_LEN] = {') - device_domains = { - 'all': 'all', - 'country': args.country, - 'region': args.region, - 'vendor': args.vendor, - 'series': args.series - } - presigs = { dom: [] for dom in device_domains } - for dom, val in device_domains.items(): - print(' {') - for i in range(args.presig_count): - serial = args.start_serial + i - ds = domain_string(dom, val, serial) - ds_hash = hashlib.sha512(ds.encode()).digest()[:16] - presigs[dom].append((ds_hash, val, serial)) - print(f' {{ /* "{ds}" */') - print(format_hex(ds_hash, indent=8, wrap=False)) - print(f' }},') - print(' },') + print('const char *presig_domain_strings[_TRIGGER_DOMAIN_COUNT] = {') + for domain in DOMAINS: + ds = domain_string(domain, getattr(args, domain)) + assert '"' not in ds + print(f' [TRIGGER_DOMAIN_{domain.upper()}] = "{ds}",') print('};') print() - presig_iv = hashlib.sha512(args.iv.encode()).digest()[:16] - print(f'uint8_t oob_presig_iv[16] = {{ /* sha512("{args.iv}")[:16] */') - print(format_hex(presig_iv, wrap=False)) - print(f'}};') + print('uint8_t presig_keys[_TRIGGER_DOMAIN_COUNT][PRESIG_MSG_LEN] = {') + for domain in DOMAINS: + key = gen_at_height(domain, getattr(args, domain), args.max_height, root_key) + print(f' [TRIGGER_DOMAIN_{domain.upper()}] = {{{format_hex(key, indent=0, wrap=False)}}},') + print('};') + + print() + print('static inline void __hack_asserts_only(void) {') + print(f' static_assert(_TRIGGER_DOMAIN_COUNT == {len(DOMAINS)});') + print(f' static_assert(PRESIG_MSG_LEN == {LINKING_KEY_SIZE});') + print('}') print() - print('uint8_t presig_store[_TRIGGER_DOMAIN_COUNT][PRESIG_STORE_SIZE][crypto_sign_BYTES] = {') - for dom, hashes in presigs.items(): - print(f' {{ /* domain {dom} */') - for ds_hash, val, serial in hashes: - authkey = os.urandom(16) - cipher = Cipher(algorithms.AES(authkey), modes.CTR(presig_iv), backend=default_backend()) - enc = cipher.encryptor() - ciphertext = enc.update(ds_hash) - assert len(enc.finalize()) == 0 +TEST_VENDOR = 'Darthenschmidt Cyberei und Verschleierungstechnik GmbH' +TEST_SERIES = 'Frobnicator v0.23.7' +TEST_REGION = 'Neuland' +TEST_COUNTRY = 'Germany' + +if __name__ == '__main__': + import argparse + parser = argparse.ArgumentParser() + parser.add_argument('keyfile', help='Key file to use') - with db: - db.execute('INSERT INTO presig_authkey VALUES (?, ?, ?, ?, ?, ?, ?, ?)', - (int(time.time()*1000), pubkey_hash, binascii.hexlify(bundle_id).decode(), PRESIG_VERSION, dom, - print(format_hex(ciphertext, indent=8, wrap=False)) - print(f' }},') + subparsers = parser.add_subparsers(title='subcommands') + keygen_parser = subparsers.add_parser('keygen', help='Generate a new key') + keygen_parser.add_argument('-f', '--force', action='store_true', help='Force overwriting existing keyfile') + keygen_parser.set_defaults(func=keygen_cmd) + + auth_parser = subparsers.add_parser('auth', help='Generate one-time authentication string') + auth_parser.add_argument('height', type=int, help='Authentication string height, counting from 0 (root key)') + auth_parser.set_defaults(func=auth_cmd) + auth_parser.add_argument('-a', '--all', action='store_const', const='all', help='Vendor name for vendor domain') + auth_parser.add_argument('-v', '--vendor', type=str, nargs='?', const=test_vendor, help='Vendor name for vendor domain') + auth_parser.add_argument('-s', '--series', type=str, nargs='?', const=test_series, help='Series identifier for series domain') + auth_parser.add_argument('-r', '--region', type=str, nargs='?', const=test_region, help='Region name for region domain') + auth_parser.add_argument('-c', '--country', type=str, nargs='?', const=test_country, help='Country name for country domain') + + prekey_parser = subparsers.add_parser('prekey', help='Generate prekey data .C source code file') + prekey_parser.add_argument('-m', '--max-height', type=int, default=8, help='Height of generated prekey') + prekey_parser.add_argument('-v', '--vendor', type=str, default=test_vendor, help='Vendor name for vendor domain') + prekey_parser.add_argument('-s', '--series', type=str, default=test_series, help='Series identifier for series domain') + prekey_parser.add_argument('-r', '--region', type=str, default=test_region, help='Region name for region domain') + prekey_parser.add_argument('-c', '--country', type=str, default=test_country, help='Country name for country domain') + prekey_parser.set_defaults(func=prekey_cmd, all='all') - print(f' }},') - print(f'}};') + args = parser.parse_args() + sys.exit(args.func(args)) - print() - print('static inline void __hack_asserts_only(void) {') - print(f' static_assert(_TRIGGER_DOMAIN_COUNT == {len(presigs)});') - print(f' static_assert(PRESIG_STORE_SIZE == {args.presig_count});') - print('}') - print() |