#!/usr/bin/env python3 # # mmgen = Multi-Mode GENerator, command-line Bitcoin cold storage solution # Copyright (C)2013-2023 The MMGen Project # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . """ autosign: Auto-sign MMGen transactions, message files and XMR wallet output files """ import sys from .cfg import Config from .util import msg,die,fmt_list,exit_if_mswin,async_run exit_if_mswin('autosigning') opts_data = { 'sets': [('stealth_led', True, 'led', True)], 'text': { 'desc': 'Auto-sign MMGen transactions, message files and XMR wallet output files', 'usage':'[opts] [operation]', 'options': """ -h, --help Print this help message --, --longhelp Print help message for long options (common options) -c, --coins=c Coins to sign for (comma-separated list) -I, --no-insert-check Don’t check for device insertion -l, --led Use status LED to signal standby, busy and error -m, --mountpoint=M Specify an alternate mountpoint 'M' (default: {asi.dfl_mountpoint!r}) -M, --mnemonic-fmt=F During setup, prompt for mnemonic seed phrase of format 'F' (choices: {mn_fmts}; default: {asi.dfl_mn_fmt!r}) -n, --no-summary Don’t print a transaction summary -s, --stealth-led Stealth LED mode - signal busy and error only, and only after successful authorization. -S, --full-summary Print a full summary of each signed transaction after each autosign run. The default list of non-MMGen outputs will not be printed. -q, --quiet Produce quieter output -v, --verbose Produce more verbose output -w, --wallet-dir=D Specify an alternate wallet dir (default: {asi.dfl_wallet_dir!r}) -x, --xmrwallets=L Range or list of wallets to be used for XMR autosigning """, 'notes': """ OPERATIONS gen_key - generate the wallet encryption key and copy it to the mountpoint {asi.mountpoint!r} (as currently configured) setup - generate both wallet encryption key and temporary signing wallet wait - start in loop mode: wait-mount-sign-unmount-wait USAGE NOTES If no operation is specified, this program mounts a removable device (typically a USB flash drive) containing unsigned MMGen transactions, message files, and/or XMR wallet output files, signs them, unmounts the removable device and exits. If invoked with ‘wait’, the program waits in a loop, mounting the removable device, performing signing operations and unmounting the device every time it is inserted. On supported platforms (currently Orange Pi, Rock Pi and Raspberry Pi boards), the status LED indicates whether the program is busy or in standby mode, i.e. ready for device insertion or removal. The removable device must have a partition labeled MMGEN_TX with a user- writable root directory and a directory named ‘/tx’, where unsigned MMGen transactions are placed. Optionally, the directory ‘/msg’ may be created and unsigned message files produced by ‘mmgen-msg’ placed there. On both the signing and online machines the mountpoint ‘{asi.mountpoint}’ (as currently configured) must exist and ‘/etc/fstab’ must contain the following entry: LABEL=MMGEN_TX {asi.mountpoint} auto noauto,user 0 0 Signing is performed with a temporary wallet created in volatile memory in the directory ‘{asi.wallet_dir}’ (as currently configured). The wallet is encrypted with a 32-byte password saved in the file ‘autosign.key’ in the root of the removable device’s filesystem. The password and temporary wallet may be created in one operation by invoking ‘mmgen-autosign setup’ with the removable device inserted. In this case, the temporary wallet is created from the user’s default wallet, if it exists and the user so desires. If not, the user is prompted to enter a seed phrase. Alternatively, the password and temporary wallet may be created separately by first invoking ‘mmgen-autosign gen_key’ and then creating and encrypting the wallet using the -P (--passwd-file) option: $ mmgen-walletconv -iwords -d{asi.wallet_dir} -p1 -N -P{asi.mountpoint}/autosign.key -Lfoo Note that the hash preset must be ‘1’. To use a wallet file as the source instead of an MMGen seed phrase, omit the ‘-i’ option and add the wallet file path to the end of the command line. Multiple temporary wallets may be created in this way and used for signing (note, however, that for XMR operations only one wallet is supported). Autosigning is currently available only on Linux-based platforms. SECURITY NOTE By placing wallet and password on separate devices, this program creates a two-factor authentication setup whereby an attacker must gain physical control of both the removable device and signing machine in order to sign transactions. It’s therefore recommended to always keep the removable device secure, separated from the signing machine and hidden (in your pocket, for example) when not transacting. In addition, since login access on the signing machine is required to steal the user’s seed, it’s good practice to lock the signing machine’s screen once the setup process is complete. As a last resort, cutting power to the signing machine will destroy the volatile memory where the temporary wallet resides and foil any attack, even if you’ve lost control of the removable device. Always remember to power off the signing machine when your signing session is over. """ }, 'code': { 'options': lambda s: s.format( asi = asi, mn_fmts = fmt_list( asi.mn_fmts, fmt='no_spc' ), ), 'notes': lambda s: s.format(asi=asi) } } def main(do_loop): asi.init_led() asi.init_exit_handler() async def do(): await asi.check_daemons_running() if do_loop: await asi.do_loop() else: ret = await asi.do_sign() asi.at_exit(not ret) async_run(do()) from .autosign import Autosign,AutosignConfig cfg = AutosignConfig( opts_data = opts_data, init_opts = { 'quiet': True, 'out_fmt': 'wallet', 'usr_randchars': 0, 'hash_preset': '1', 'label': 'Autosign Wallet', }, do_post_init = True ) cmd_args = cfg._args asi = Autosign(cfg) cfg._post_init() if len(cmd_args) not in (0,1): cfg._opts.usage() if cmd_args: cmd = cmd_args[0] if cmd == 'gen_key': asi.gen_key() elif cmd == 'setup': asi.setup() from .ui import keypress_confirm if cfg.xmrwallets and keypress_confirm( cfg, '\nContinue with Monero setup?', default_yes=True ): msg('') asi.xmr_setup() elif cmd == 'wait': main(do_loop=True) else: die(1,f'{cmd!r}: unrecognized command') else: main(do_loop=False)