You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
trezor-agent/trezor_agent/trezor/client.py

151 lines
5.0 KiB
Python

import io
import re
import struct
import binascii
import logging
from .. import util
from .. import formats
from . import _factory as TrezorFactory
log = logging.getLogger(__name__)
class Client(object):
MIN_VERSION = [1, 3, 4]
def __init__(self, factory=TrezorFactory, curve=formats.CURVE_NIST256):
self.curve = curve
self.factory = factory
self.client = self.factory.client()
f = self.client.features
log.debug('connected to Trezor %s', f.device_id)
log.debug('label : %s', f.label)
log.debug('vendor : %s', f.vendor)
version = [f.major_version, f.minor_version, f.patch_version]
version_str = '.'.join([str(v) for v in version])
log.debug('version : %s', version_str)
log.debug('revision : %s', binascii.hexlify(f.revision))
if version < self.MIN_VERSION:
fmt = 'Please upgrade your TREZOR to v{}+ firmware'
version_str = '.'.join([str(v) for v in self.MIN_VERSION])
raise ValueError(fmt.format(version_str))
def __enter__(self):
msg = 'Hello World!'
assert self.client.ping(msg) == msg
return self
def __exit__(self, *args):
log.info('disconnected from Trezor')
self.client.clear_session() # forget PIN and shutdown screen
self.client.close()
def get_identity(self, label):
identity = string_to_identity(label, self.factory.identity_type)
identity.proto = 'ssh'
return identity
def get_public_key(self, label):
identity = self.get_identity(label=label)
label = identity_to_string(identity) # canonize key label
log.info('getting "%s" public key (%s) from Trezor...',
label, self.curve)
addr = _get_address(identity)
node = self.client.get_public_node(n=addr,
ecdsa_curve_name=self.curve)
pubkey = node.node.public_key
vk = formats.decompress_pubkey(pubkey=pubkey, curve_name=self.curve)
return formats.export_public_key(vk=vk, label=label)
def sign_ssh_challenge(self, label, blob):
identity = self.get_identity(label=label)
msg = _parse_ssh_blob(blob)
log.info('please confirm user "%s" login to "%s" using Trezor...',
msg['user'], label)
visual = identity.path # not signed when proto='ssh'
result = self.client.sign_identity(identity=identity,
challenge_hidden=blob,
challenge_visual=visual,
ecdsa_curve_name=self.curve)
verifying_key = formats.decompress_pubkey(pubkey=result.public_key,
curve_name=self.curve)
key_type, blob = formats.serialize_verifying_key(verifying_key)
assert blob == msg['public_key']['blob']
assert key_type == msg['key_type']
assert len(result.signature) == 65
assert result.signature[:1] == bytearray([0])
return result.signature[1:]
_identity_regexp = re.compile(''.join([
'^'
r'(?:(?P<proto>.*)://)?',
r'(?:(?P<user>.*)@)?',
r'(?P<host>.*?)',
r'(?::(?P<port>\w*))?',
r'(?P<path>/.*)?',
'$'
]))
def string_to_identity(s, identity_type):
m = _identity_regexp.match(s)
result = m.groupdict()
log.debug('parsed identity: %s', result)
kwargs = {k: v for k, v in result.items() if v}
return identity_type(**kwargs)
def identity_to_string(identity):
result = []
if identity.proto:
result.append(identity.proto + '://')
if identity.user:
result.append(identity.user + '@')
result.append(identity.host)
if identity.port:
result.append(':' + identity.port)
if identity.path:
result.append(identity.path)
return ''.join(result)
def _get_address(identity):
index = struct.pack('<L', identity.index)
addr = index + identity_to_string(identity).encode('ascii')
log.debug('address string: %r', addr)
digest = formats.hashfunc(addr).digest()
s = io.BytesIO(bytearray(digest))
hardened = 0x80000000
address_n = [13] + list(util.recv(s, '<LLLL'))
return [(hardened | value) for value in address_n]
def _parse_ssh_blob(data):
res = {}
if data:
i = io.BytesIO(data)
res['nonce'] = util.read_frame(i)
i.read(1) # TBD
res['user'] = util.read_frame(i)
res['conn'] = util.read_frame(i)
res['auth'] = util.read_frame(i)
i.read(1) # TBD
res['key_type'] = util.read_frame(i)
public_key = util.read_frame(i)
res['public_key'] = formats.parse_pubkey(public_key)
assert not i.read()
log.debug('%s: user %r via %r (%r)',
res['conn'], res['user'], res['auth'], res['key_type'])
log.debug('nonce: %s', binascii.hexlify(res['nonce']))
log.debug('fingerprint: %s', res['public_key']['fingerprint'])
return res