mirror of
https://github.com/trezor/trezor-firmware.git
synced 2024-11-17 21:22:10 +00:00
84 lines
2.6 KiB
Python
84 lines
2.6 KiB
Python
# This file is part of the TREZOR project.
|
|
#
|
|
# Copyright (C) 2012-2016 Marek Palatinus <slush@satoshilabs.com>
|
|
# Copyright (C) 2012-2016 Pavol Rusnak <stick@satoshilabs.com>
|
|
#
|
|
# This library is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU Lesser General Public License as published by
|
|
# the Free Software Foundation, either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
#
|
|
# This library 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 Lesser General Public License for more details.
|
|
#
|
|
# You should have received a copy of the GNU Lesser General Public License
|
|
# along with this library. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
from __future__ import absolute_import
|
|
|
|
from io import BytesIO
|
|
import struct
|
|
from . import mapping
|
|
from . import protobuf
|
|
|
|
REPLEN = 64
|
|
|
|
|
|
class ProtocolV1(object):
|
|
|
|
def session_begin(self, transport):
|
|
pass
|
|
|
|
def session_end(self, transport):
|
|
pass
|
|
|
|
def write(self, transport, msg):
|
|
data = BytesIO()
|
|
protobuf.dump_message(data, msg)
|
|
ser = data.getvalue()
|
|
header = struct.pack(">HL", mapping.get_type(msg), len(ser))
|
|
data = bytearray(b"##" + header + ser)
|
|
|
|
while data:
|
|
# Report ID, data padded to 63 bytes
|
|
chunk = b'?' + data[:REPLEN - 1]
|
|
chunk = chunk.ljust(REPLEN, b'\x00')
|
|
transport.write_chunk(chunk)
|
|
data = data[63:]
|
|
|
|
def read(self, transport):
|
|
# Read header with first part of message data
|
|
chunk = transport.read_chunk()
|
|
(msg_type, datalen, data) = self.parse_first(chunk)
|
|
|
|
# Read the rest of the message
|
|
while len(data) < datalen:
|
|
chunk = transport.read_chunk()
|
|
data.extend(self.parse_next(chunk))
|
|
|
|
# Strip padding
|
|
data = BytesIO(data[:datalen])
|
|
|
|
# Parse to protobuf
|
|
msg = protobuf.load_message(data, mapping.get_class(msg_type))
|
|
return msg
|
|
|
|
def parse_first(self, chunk):
|
|
if chunk[:3] != b'?##':
|
|
raise RuntimeError('Unexpected magic characters')
|
|
try:
|
|
headerlen = struct.calcsize('>HL')
|
|
(msg_type, datalen) = struct.unpack('>HL', chunk[3:3 + headerlen])
|
|
except:
|
|
raise RuntimeError('Cannot parse header')
|
|
|
|
data = chunk[3 + headerlen:]
|
|
return (msg_type, datalen, data)
|
|
|
|
def parse_next(self, chunk):
|
|
if chunk[:1] != b'?':
|
|
raise RuntimeError('Unexpected magic characters')
|
|
return chunk[1:]
|