wownero-python/monero/seed.py
2018-06-04 12:53:45 +02:00

173 lines
6.8 KiB
Python

#!/usr/bin/env python
# Electrum - lightweight Bitcoin client
# Copyright (C) 2011 thomasv@gitorious
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation files
# (the "Software"), to deal in the Software without restriction,
# including without limitation the rights to use, copy, modify, merge,
# publish, distribute, sublicense, and/or sell copies of the Software,
# and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
#
# Note about US patent no 5892470: Here each word does not represent a given digit.
# Instead, the digit represented by a word is variable, it depends on the previous word.
#
# Copied 17 February 2018 from MoneroPy, originally from Electrum:
# https://github.com/bigreddmachine/MoneroPy/blob/master/moneropy/mnemonic.py ch: 80cc16c39b16c55a8d052fbf7fae68644f7a5f02
# https://github.com/spesmilo/electrum/blob/master/lib/old_mnemonic.py ch:9a0aa9b4783ea03ea13c6d668e080e0cdf261c5b
#
# Significantly modified on 26 May 2018 by Michal Salaban:
# + support for 12/13-word seeds
# + simplified interface, changed exceptions (assertions -> explicit raise)
# + optimization
from monero import wordlists
from monero import ed25519
from monero import base58
from monero.address import address
from binascii import hexlify, unhexlify
from os import urandom
from sha3 import keccak_256
class Seed(object):
"""Creates a seed object either from local system randomness or an imported phrase.
:rtype: :class:`Seed <monero.seed.Seed>`
"""
def __init__(self, phrase_or_hex="", wordlist="English"):
"""If user supplied a seed string to the class, break it down and determine
if it's hexadecimal or mnemonic word string. Gather the values and store them.
If no seed is passed, automatically generate a new one from local system randomness.
:rtype: :class:`Seed <monero.seed.Seed>`
"""
self.phrase = "" #13 or 25 word mnemonic word string
self.hex = "" # hexadecimal
self.word_list = wordlists.get_wordlist(wordlist)
if phrase_or_hex:
seed_split = phrase_or_hex.split(" ")
if len(seed_split) >= 24:
# standard mnemonic
self.phrase = phrase_or_hex
if len(seed_split) == 25:
# with checksum
self._validate_checksum()
self._decode_seed()
elif len(seed_split) >= 12:
# mymonero mnemonic
self.phrase = phrase_or_hex
if len(seed_split) == 13:
# with checksum
self._validate_checksum()
self._decode_seed()
elif len(seed_split) == 1:
# single string, probably hex, but confirm
if not len(phrase_or_hex) % 8 == 0:
raise ValueError("Not valid hexadecimal: {hex}".format(hex=phrase_or_hex))
self.hex = phrase_or_hex
self._encode_seed()
else:
raise ValueError("Not valid mnemonic phrase or hex: {arg}".format(arg=phrase_or_hex))
else:
self.hex = generate_hex()
self._encode_seed()
def is_mymonero(self):
"""Returns True if the seed is MyMonero-style (12/13-word)."""
return len(self.hex) == 32
def _encode_seed(self):
"""Convert hexadecimal string to mnemonic word representation with checksum.
"""
self.phrase = self.word_list.encode(self.hex)
def _decode_seed(self):
"""Calculate hexadecimal representation of the phrase.
"""
self.hex = self.word_list.decode(self.phrase)
def _validate_checksum(self):
"""Given a mnemonic word string, confirm seed checksum (last word) matches the computed checksum.
:rtype: bool
"""
phrase = self.phrase.split(" ")
if self.word_list.get_checksum(self.phrase) == phrase[-1]:
return True
raise ValueError("Invalid checksum")
def sc_reduce(self, input):
integer = ed25519.decodeint(input)
modulo = integer % ed25519.l
return hexlify(ed25519.encodeint(modulo)).decode()
def hex_seed(self):
return self.hex
def _hex_seed_keccak(self):
h = keccak_256()
h.update(unhexlify(self.hex))
return h.digest()
def secret_spend_key(self):
a = self._hex_seed_keccak() if self.is_mymonero() else unhexlify(self.hex)
return self.sc_reduce(a)
def secret_view_key(self):
b = self._hex_seed_keccak() if self.is_mymonero() else unhexlify(self.secret_spend_key())
h = keccak_256()
h.update(b)
return self.sc_reduce(h.digest())
def public_spend_key(self):
keyInt = ed25519.decodeint(unhexlify(self.secret_spend_key()))
aG = ed25519.scalarmultbase(keyInt)
return hexlify(ed25519.encodepoint(aG)).decode()
def public_view_key(self):
keyInt = ed25519.decodeint(unhexlify(self.secret_view_key()))
aG = ed25519.scalarmultbase(keyInt)
return hexlify(ed25519.encodepoint(aG)).decode()
def public_address(self, net='mainnet'):
"""Returns the master :class:`Address <monero.address.Address>` represented by the seed.
:param net: the network, one of 'mainnet', 'testnet', 'stagenet'. Default is 'mainnet'.
:rtype: :class:`Address <monero.address.Address>`
"""
if net not in ('mainnet', 'testnet', 'stagenet'):
raise ValueError(
"Invalid net argument. Must be one of ('mainnet', 'testnet', 'stagenet').")
netbyte = 18 if net == 'mainnet' else 53 if net == 'testnet' else 24
data = "{:x}{:s}{:s}".format(netbyte, self.public_spend_key(), self.public_view_key())
h = keccak_256()
h.update(unhexlify(data))
checksum = h.hexdigest()
return address(base58.encode(data + checksum[0:8]))
def generate_hex(n_bytes=32):
"""Generate a secure and random hexadecimal string. 32 bytes by default, but arguments can override.
:rtype: str
"""
h = hexlify(urandom(n_bytes))
return "".join(h.decode("utf-8"))