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LedgerUsbDevice initial cleanup
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- remove ledgerblue dependency
- pack all device comm in LedgerUsbDevice class
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@bargst
bargst committed Jun 20, 2018
1 parent 935c1fc commit b181bc4
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Showing 2 changed files with 105 additions and 166 deletions.
269 changes: 104 additions & 165 deletions eth_account/signers/ledger.py
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4,8 +4,6 @@
import eth_utils
import rlp

import ledgerblue.comm

from hexbytes import HexBytes

from eth_account import (
Expand Down Expand Up @@ -38,122 +36,17 @@
ETH_DERIVATION_PATH_PREFIX = "m/44'/60'/0'/"



TIMEOUT=20000
import sys
from binascii import hexlify
def hexstr(bstr):
if (sys.version_info.major == 3):
return hexlify(bstr).decode()
if (sys.version_info.major == 2):
return hexlify(bstr)
return "<undecoded APDU<"

class CommException(Exception):

def __init__(self, message, sw=0x6f00, data=None):
self.message = message
self.sw = sw
self.data = data

def __str__(self):
buf = "Exception : " + self.message
return buf

def wrapCommandAPDU(channel, command, packetSize, ble=False):
if packetSize < 3:
raise CommException("Can't handle Ledger framing with less than 3 bytes for the report")
sequenceIdx = 0
offset = 0
if not ble:
result = struct.pack(">H", channel)
extraHeaderSize = 2
else:
result = ""
extraHeaderSize = 0
result += struct.pack(">BHH", 0x05, sequenceIdx, len(command))
sequenceIdx = sequenceIdx + 1
if len(command) > packetSize - 5 - extraHeaderSize:
blockSize = packetSize - 5 - extraHeaderSize
else:
blockSize = len(command)
result += command[offset : offset + blockSize]
offset = offset + blockSize
while offset != len(command):
if not ble:
result += struct.pack(">H", channel)
result += struct.pack(">BH", 0x05, sequenceIdx)
sequenceIdx = sequenceIdx + 1
if (len(command) - offset) > packetSize - 3 - extraHeaderSize:
blockSize = packetSize - 3 - extraHeaderSize
else:
blockSize = len(command) - offset
result += command[offset : offset + blockSize]
offset = offset + blockSize
if not ble:
while (len(result) % packetSize) != 0:
result += b"\x00"
return bytearray(result)

def unwrapResponseAPDU(channel, data, packetSize, ble=False):
sequenceIdx = 0
offset = 0
if not ble:
extraHeaderSize = 2
else:
extraHeaderSize = 0
if ((data is None) or (len(data) < 5 + extraHeaderSize + 5)):
return None
if not ble:
if struct.unpack(">H", data[offset : offset + 2])[0] != channel:
raise CommException("Invalid channel")
offset += 2
if data[offset] != 0x05:
raise CommException("Invalid tag")
offset += 1
if struct.unpack(">H", data[offset : offset + 2])[0] != sequenceIdx:
raise CommException("Invalid sequence")
offset += 2
responseLength = struct.unpack(">H", data[offset : offset + 2])[0]
offset += 2
if len(data) < 5 + extraHeaderSize + responseLength:
return None
if responseLength > packetSize - 5 - extraHeaderSize:
blockSize = packetSize - 5 - extraHeaderSize
else:
blockSize = responseLength
result = data[offset : offset + blockSize]
offset += blockSize
while (len(result) != responseLength):
sequenceIdx = sequenceIdx + 1
if (offset == len(data)):
return None
if not ble:
if struct.unpack(">H", data[offset : offset + 2])[0] != channel:
raise CommException("Invalid channel")
offset += 2
if data[offset] != 0x05:
raise CommException("Invalid tag")
offset += 1
if struct.unpack(">H", data[offset : offset + 2])[0] != sequenceIdx:
raise CommException("Invalid sequence")
offset += 2
if (responseLength - len(result)) > packetSize - 3 - extraHeaderSize:
blockSize = packetSize - 3 - extraHeaderSize
else:
blockSize = responseLength - len(result)
result += data[offset : offset + blockSize]
offset += blockSize
return bytearray(result)

import hid
import time
class USBDevice:
class LedgerUsbDevice:
'''
References:
- https://github.com/LedgerHQ/blue-loader-python/blob/master/ledgerblue/comm.py#L56
- https://github.com/ethereum/go-ethereum/blob/master/accounts/usbwallet/ledger.go
'''

def __init__(self, debug=False):
dev = None
hidDevicePath = None
ledger = True
for hidDevice in hid.enumerate(0, 0):
if hidDevice['vendor_id'] == 0x2c97:
if ('interface_number' in hidDevice and hidDevice['interface_number'] == 0) or ('usage_page' in hidDevice and hidDevice['usage_page'] == 0xffa0):
Expand All @@ -163,67 +56,49 @@ def __init__(self, debug=False):
dev.open_path(hidDevicePath)
dev.set_nonblocking(True)
else:
raise CommException("No dongle found")
raise Exception("No dongle found")
self.device = dev
self.ledger = ledger
self.debug = debug
self.waitImpl = self
self.opened = True

def exchange(self, apdu, timeout=TIMEOUT):
def exchange(self, apdu, timeout=20000):
if self.debug:
print("HID => %s" % hexstr(apdu))
if self.ledger:
apdu = wrapCommandAPDU(0x0101, apdu, 64)
print("HID => %s" % to_hex(apdu))

# Construct the wraped payload
apdu = self.wrapCommandAPDU(0x0101, apdu, 64)
padSize = len(apdu) % 64
tmp = apdu
if padSize != 0:
tmp.extend([0] * (64 - padSize))

# Send to device
offset = 0
while(offset != len(tmp)):
data = tmp[offset:offset + 64]
data = bytearray([0]) + data
if self.device.write(data) < 0:
raise BaseException("Error while writing")
offset += 64

# Receive reply
dataLength = 0
dataStart = 2
result = self.waitImpl.waitFirstResponse(timeout)
if not self.ledger:
if result[0] == 0x61: # 61xx : data available
self.device.set_nonblocking(False)
dataLength = result[1]
dataLength += 2
if dataLength > 62:
remaining = dataLength - 62
while(remaining != 0):
if remaining > 64:
blockLength = 64
else:
blockLength = remaining
result.extend(bytearray(self.device.read(65))[0:blockLength])
remaining -= blockLength
swOffset = dataLength
dataLength -= 2
result = self.waitFirstResponse(timeout)
self.device.set_nonblocking(False)
while True:
response = self.unwrapResponseAPDU(0x0101, result, 64)
if response is not None:
result = response
dataStart = 0
swOffset = len(response) - 2
dataLength = len(response) - 2
self.device.set_nonblocking(True)
else:
swOffset = 0
else:
self.device.set_nonblocking(False)
while True:
response = unwrapResponseAPDU(0x0101, result, 64)
if response is not None:
result = response
dataStart = 0
swOffset = len(response) - 2
dataLength = len(response) - 2
self.device.set_nonblocking(True)
break
result.extend(bytearray(self.device.read(65)))
break
result.extend(bytearray(self.device.read(65)))
sw = (result[swOffset] << 8) + result[swOffset + 1]
response = result[dataStart : dataLength + dataStart]
if self.debug:
print("HID <= %s%.2x" % (hexstr(response), sw))
print("HID <= %s %.2x" % (to_hex(response), sw))
if sw != 0x9000:
possibleCause = "Unknown reason"
if sw == 0x6982:
Expand All @@ -234,7 +109,7 @@ def exchange(self, apdu, timeout=TIMEOUT):
possibleCause = "Not enough space?"
if sw == 0x6484:
possibleCause = "Are you using the correct targetId?"
raise CommException("Invalid status %04x (%s)" % (sw, possibleCause), sw, response)
raise Exception("Invalid status %04x (%s)" % (sw, possibleCause))
return response

def waitFirstResponse(self, timeout):
Expand All @@ -244,20 +119,84 @@ def waitFirstResponse(self, timeout):
data = self.device.read(65)
if not len(data):
if time.time() - start > timeout:
raise CommException("Timeout")
raise Exception("Timeout")
time.sleep(0.0001)
return bytearray(data)

def apduMaxDataSize(self):
return 255
def wrapCommandAPDU(self, channel, command, packetSize):
if packetSize < 3:
raise Exception("Can't handle Ledger framing with less than 3 bytes for the report")
sequenceIdx = 0
offset = 0
result = struct.pack(">H", channel)
extraHeaderSize = 2
result += struct.pack(">BHH", 0x05, sequenceIdx, len(command))
sequenceIdx = sequenceIdx + 1
if len(command) > packetSize - 5 - extraHeaderSize:
blockSize = packetSize - 5 - extraHeaderSize
else:
blockSize = len(command)
result += command[offset : offset + blockSize]
offset = offset + blockSize
while offset != len(command):
result += struct.pack(">H", channel)
result += struct.pack(">BH", 0x05, sequenceIdx)
sequenceIdx = sequenceIdx + 1
if (len(command) - offset) > packetSize - 3 - extraHeaderSize:
blockSize = packetSize - 3 - extraHeaderSize
else:
blockSize = len(command) - offset
result += command[offset : offset + blockSize]
offset = offset + blockSize
while (len(result) % packetSize) != 0:
result += b"\x00"
return bytearray(result)

def close(self):
if self.opened:
try:
self.device.close()
except:
pass
self.opened = False
def unwrapResponseAPDU(self, channel, data, packetSize):
sequenceIdx = 0
offset = 0
extraHeaderSize = 2
if ((data is None) or (len(data) < 5 + extraHeaderSize + 5)):
return None
if struct.unpack(">H", data[offset : offset + 2])[0] != channel:
raise Exception("Invalid channel")
offset += 2
if data[offset] != 0x05:
raise Exception("Invalid tag")
offset += 1
if struct.unpack(">H", data[offset : offset + 2])[0] != sequenceIdx:
raise Exception("Invalid sequence")
offset += 2
responseLength = struct.unpack(">H", data[offset : offset + 2])[0]
offset += 2
if len(data) < 5 + extraHeaderSize + responseLength:
return None
if responseLength > packetSize - 5 - extraHeaderSize:
blockSize = packetSize - 5 - extraHeaderSize
else:
blockSize = responseLength
result = data[offset : offset + blockSize]
offset += blockSize
while (len(result) != responseLength):
sequenceIdx = sequenceIdx + 1
if (offset == len(data)):
return None
if struct.unpack(">H", data[offset : offset + 2])[0] != channel:
raise Exception("Invalid channel")
offset += 2
if data[offset] != 0x05:
raise Exception("Invalid tag")
offset += 1
if struct.unpack(">H", data[offset : offset + 2])[0] != sequenceIdx:
raise Exception("Invalid sequence")
offset += 2
if (responseLength - len(result)) > packetSize - 3 - extraHeaderSize:
blockSize = packetSize - 3 - extraHeaderSize
else:
blockSize = responseLength - len(result)
result += data[offset : offset + blockSize]
offset += blockSize
return bytearray(result)


class LedgerAccount(BaseAccount):
Expand Down Expand Up @@ -327,7 +266,7 @@ def _path_to_bytes(self, path):

def _send_to_device(self, apdu):
if self.device is None:
self.device = USBDevice(debug=True)
self.device = LedgerUsbDevice(debug=True)

reply = self.device.exchange(apdu, timeout=60)

Expand Down
2 changes: 1 addition & 1 deletion setup.py
View file
Original file line number Diff line number Diff line change
Expand Up @@ -7,7 +7,7 @@

extras_require={
'ledger': [
"ledgerblue>=0.1.17,<0.2.0",
"hidapi>=0.7.99",
],
'test': [
"pytest==3.3.2",
Expand Down

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