lukechilds
/
electrum
mirror of https://github.com/lukechilds/electrum.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
13239 Commits
21 Branches
132 Tags
52 MiB
 
 
 
 
Tree: a2122a8c19
Branches Tags
${ item.name }
Create tag ${ searchTerm }
Create branch ${ searchTerm }
from 'a2122a8c19'
${ noResults }
electrum/electrum/interface.py

1104 lines
45 KiB
Raw Blame History

#!/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.
import os
import re
import ssl
import sys
import traceback
import asyncio
import socket
from typing import Tuple, Union, List, TYPE_CHECKING, Optional, Set, NamedTuple, Any, Sequence
from collections import defaultdict
from ipaddress import IPv4Network, IPv6Network, ip_address, IPv6Address, IPv4Address
import itertools
import logging
import hashlib
import aiorpcx
from aiorpcx import TaskGroup
from aiorpcx import RPCSession, Notification, NetAddress, NewlineFramer
from aiorpcx.curio import timeout_after, TaskTimeout
from aiorpcx.jsonrpc import JSONRPC, CodeMessageError
from aiorpcx.rawsocket import RSClient
import certifi
from .util import (ignore_exceptions, log_exceptions, bfh, SilentTaskGroup, MySocksProxy,
is_integer, is_non_negative_integer, is_hash256_str, is_hex_str,
is_int_or_float, is_non_negative_int_or_float)
from . import util
from . import x509
from . import pem
from . import version
from . import blockchain
from .blockchain import Blockchain, HEADER_SIZE
from . import bitcoin
from . import constants
from .i18n import _
from .logging import Logger
from .transaction import Transaction
if TYPE_CHECKING:
from .network import Network
from .simple_config import SimpleConfig
ca_path = certifi.where()
BUCKET_NAME_OF_ONION_SERVERS = 'onion'
MAX_INCOMING_MSG_SIZE = 1_000_000 # in bytes
_KNOWN_NETWORK_PROTOCOLS = {'t', 's'}
PREFERRED_NETWORK_PROTOCOL = 's'
assert PREFERRED_NETWORK_PROTOCOL in _KNOWN_NETWORK_PROTOCOLS
class NetworkTimeout:
# seconds
class Generic:
NORMAL = 30
RELAXED = 45
MOST_RELAXED = 600
class Urgent(Generic):
NORMAL = 10
RELAXED = 20
MOST_RELAXED = 60
def assert_non_negative_integer(val: Any) -> None:
if not is_non_negative_integer(val):
raise RequestCorrupted(f'{val!r} should be a non-negative integer')
def assert_integer(val: Any) -> None:
if not is_integer(val):
raise RequestCorrupted(f'{val!r} should be an integer')
def assert_int_or_float(val: Any) -> None:
if not is_int_or_float(val):
raise RequestCorrupted(f'{val!r} should be int or float')
def assert_non_negative_int_or_float(val: Any) -> None:
if not is_non_negative_int_or_float(val):
raise RequestCorrupted(f'{val!r} should be a non-negative int or float')
def assert_hash256_str(val: Any) -> None:
if not is_hash256_str(val):
raise RequestCorrupted(f'{val!r} should be a hash256 str')
def assert_hex_str(val: Any) -> None:
if not is_hex_str(val):
raise RequestCorrupted(f'{val!r} should be a hex str')
def assert_dict_contains_field(d: Any, *, field_name: str) -> Any:
if not isinstance(d, dict):
raise RequestCorrupted(f'{d!r} should be a dict')
if field_name not in d:
raise RequestCorrupted(f'required field {field_name!r} missing from dict')
return d[field_name]
def assert_list_or_tuple(val: Any) -> None:
if not isinstance(val, (list, tuple)):
raise RequestCorrupted(f'{val!r} should be a list or tuple')
class NotificationSession(RPCSession):
def __init__(self, *args, interface: 'Interface', **kwargs):
super(NotificationSession, self).__init__(*args, **kwargs)
self.subscriptions = defaultdict(list)
self.cache = {}
self.default_timeout = NetworkTimeout.Generic.NORMAL
self._msg_counter = itertools.count(start=1)
self.interface = interface
self.cost_hard_limit = 0 # disable aiorpcx resource limits
async def handle_request(self, request):
self.maybe_log(f"--> {request}")
try:
if isinstance(request, Notification):
params, result = request.args[:-1], request.args[-1]
key = self.get_hashable_key_for_rpc_call(request.method, params)
if key in self.subscriptions:
self.cache[key] = result
for queue in self.subscriptions[key]:
await queue.put(request.args)
else:
raise Exception(f'unexpected notification')
else:
raise Exception(f'unexpected request. not a notification')
except Exception as e:
self.interface.logger.info(f"error handling request {request}. exc: {repr(e)}")
await self.close()
async def send_request(self, *args, timeout=None, **kwargs):
# note: semaphores/timeouts/backpressure etc are handled by
# aiorpcx. the timeout arg here in most cases should not be set
msg_id = next(self._msg_counter)
self.maybe_log(f"<-- {args} {kwargs} (id: {msg_id})")
try:
# note: RPCSession.send_request raises TaskTimeout in case of a timeout.
# TaskTimeout is a subclass of CancelledError, which is *suppressed* in TaskGroups
response = await asyncio.wait_for(
super().send_request(*args, **kwargs),
timeout)
except (TaskTimeout, asyncio.TimeoutError) as e:
raise RequestTimedOut(f'request timed out: {args} (id: {msg_id})') from e
except CodeMessageError as e:
self.maybe_log(f"--> {repr(e)} (id: {msg_id})")
raise
else:
self.maybe_log(f"--> {response} (id: {msg_id})")
return response
def set_default_timeout(self, timeout):
self.sent_request_timeout = timeout
self.max_send_delay = timeout
async def subscribe(self, method: str, params: List, queue: asyncio.Queue):
# note: until the cache is written for the first time,
# each 'subscribe' call might make a request on the network.
key = self.get_hashable_key_for_rpc_call(method, params)
self.subscriptions[key].append(queue)
if key in self.cache:
result = self.cache[key]
else:
result = await self.send_request(method, params)
self.cache[key] = result
await queue.put(params + [result])
def unsubscribe(self, queue):
"""Unsubscribe a callback to free object references to enable GC."""
# note: we can't unsubscribe from the server, so we keep receiving
# subsequent notifications
for v in self.subscriptions.values():
if queue in v:
v.remove(queue)
@classmethod
def get_hashable_key_for_rpc_call(cls, method, params):
"""Hashable index for subscriptions and cache"""
return str(method) + repr(params)
def maybe_log(self, msg: str) -> None:
if not self.interface: return
if self.interface.debug or self.interface.network.debug:
self.interface.logger.debug(msg)
def default_framer(self):
# overridden so that max_size can be customized
max_size = int(self.interface.network.config.get('network_max_incoming_msg_size',
MAX_INCOMING_MSG_SIZE))
return NewlineFramer(max_size=max_size)
class NetworkException(Exception): pass
class GracefulDisconnect(NetworkException):
log_level = logging.INFO
def __init__(self, *args, log_level=None, **kwargs):
Exception.__init__(self, *args, **kwargs)
if log_level is not None:
self.log_level = log_level
class RequestTimedOut(GracefulDisconnect):
def __str__(self):
return _("Network request timed out.")
class RequestCorrupted(Exception): pass
class ErrorParsingSSLCert(Exception): pass
class ErrorGettingSSLCertFromServer(Exception): pass
class ErrorSSLCertFingerprintMismatch(Exception): pass
class InvalidOptionCombination(Exception): pass
class ConnectError(NetworkException): pass
class _RSClient(RSClient):
async def create_connection(self):
try:
return await super().create_connection()
except OSError as e:
# note: using "from e" here will set __cause__ of ConnectError
raise ConnectError(e) from e
class ServerAddr:
def __init__(self, host: str, port: Union[int, str], *, protocol: str = None):
assert isinstance(host, str), repr(host)
if protocol is None:
protocol = 's'
if not host:
raise ValueError('host must not be empty')
if host[0] == '[' and host[-1] == ']': # IPv6
host = host[1:-1]
try:
net_addr = NetAddress(host, port) # this validates host and port
except Exception as e:
raise ValueError(f"cannot construct ServerAddr: invalid host or port (host={host}, port={port})") from e
if protocol not in _KNOWN_NETWORK_PROTOCOLS:
raise ValueError(f"invalid network protocol: {protocol}")
self.host = str(net_addr.host) # canonical form (if e.g. IPv6 address)
self.port = int(net_addr.port)
self.protocol = protocol
self._net_addr_str = str(net_addr)
@classmethod
def from_str(cls, s: str) -> 'ServerAddr':
# host might be IPv6 address, hence do rsplit:
host, port, protocol = str(s).rsplit(':', 2)
return ServerAddr(host=host, port=port, protocol=protocol)
@classmethod
def from_str_with_inference(cls, s: str) -> Optional['ServerAddr']:
"""Construct ServerAddr from str, guessing missing details.
Ongoing compatibility not guaranteed.
"""
if not s:
return None
items = str(s).rsplit(':', 2)
if len(items) < 2:
return None # although maybe we could guess the port too?
host = items[0]
port = items[1]
if len(items) >= 3:
protocol = items[2]
else:
protocol = PREFERRED_NETWORK_PROTOCOL
return ServerAddr(host=host, port=port, protocol=protocol)
def to_friendly_name(self) -> str:
# note: this method is closely linked to from_str_with_inference
if self.protocol == 's': # hide trailing ":s"
return self.net_addr_str()
return str(self)
def __str__(self):
return '{}:{}'.format(self.net_addr_str(), self.protocol)
def to_json(self) -> str:
return str(self)
def __repr__(self):
return f'<ServerAddr host={self.host} port={self.port} protocol={self.protocol}>'
def net_addr_str(self) -> str:
return self._net_addr_str
def __eq__(self, other):
if not isinstance(other, ServerAddr):
return False
return (self.host == other.host
and self.port == other.port
and self.protocol == other.protocol)
def __ne__(self, other):
return not (self == other)
def __hash__(self):
return hash((self.host, self.port, self.protocol))
def _get_cert_path_for_host(*, config: 'SimpleConfig', host: str) -> str:
filename = host
try:
ip = ip_address(host)
except ValueError:
pass
else:
if isinstance(ip, IPv6Address):
filename = f"ipv6_{ip.packed.hex()}"
return os.path.join(config.path, 'certs', filename)
class Interface(Logger):
LOGGING_SHORTCUT = 'i'
def __init__(self, *, network: 'Network', server: ServerAddr, proxy: Optional[dict]):
self.ready = asyncio.Future()
self.got_disconnected = asyncio.Future()
self.server = server
Logger.__init__(self)
assert network.config.path
self.cert_path = _get_cert_path_for_host(config=network.config, host=self.host)
self.blockchain = None # type: Optional[Blockchain]
self._requested_chunks = set() # type: Set[int]
self.network = network
self.proxy = MySocksProxy.from_proxy_dict(proxy)
self.session = None # type: Optional[NotificationSession]
self._ipaddr_bucket = None
# Latest block header and corresponding height, as claimed by the server.
# Note that these values are updated before they are verified.
# Especially during initial header sync, verification can take a long time.
# Failing verification will get the interface closed.
self.tip_header = None
self.tip = 0
self.fee_estimates_eta = {}
# Dump network messages (only for this interface). Set at runtime from the console.
self.debug = False
asyncio.run_coroutine_threadsafe(
self.network.taskgroup.spawn(self.run()), self.network.asyncio_loop)
self.taskgroup = SilentTaskGroup()
@property
def host(self):
return self.server.host
@property
def port(self):
return self.server.port
@property
def protocol(self):
return self.server.protocol
def diagnostic_name(self):
return self.server.net_addr_str()
def __str__(self):
return f"<Interface {self.diagnostic_name()}>"
async def is_server_ca_signed(self, ca_ssl_context):
"""Given a CA enforcing SSL context, returns True if the connection
can be established. Returns False if the server has a self-signed
certificate but otherwise is okay. Any other failures raise.
"""
try:
await self.open_session(ca_ssl_context, exit_early=True)
except ConnectError as e:
cause = e.__cause__
if isinstance(cause, ssl.SSLError) and cause.reason == 'CERTIFICATE_VERIFY_FAILED':
# failures due to self-signed certs are normal
return False
raise
return True
async def _try_saving_ssl_cert_for_first_time(self, ca_ssl_context):
ca_signed = await self.is_server_ca_signed(ca_ssl_context)
if ca_signed:
if self._get_expected_fingerprint():
raise InvalidOptionCombination("cannot use --serverfingerprint with CA signed servers")
with open(self.cert_path, 'w') as f:
# empty file means this is CA signed, not self-signed
f.write('')
else:
await self._save_certificate()
def _is_saved_ssl_cert_available(self):
if not os.path.exists(self.cert_path):
return False
with open(self.cert_path, 'r') as f:
contents = f.read()
if contents == '': # CA signed
if self._get_expected_fingerprint():
raise InvalidOptionCombination("cannot use --serverfingerprint with CA signed servers")
return True
# pinned self-signed cert
try:
b = pem.dePem(contents, 'CERTIFICATE')
except SyntaxError as e:
self.logger.info(f"error parsing already saved cert: {e}")
raise ErrorParsingSSLCert(e) from e
try:
x = x509.X509(b)
except Exception as e:
self.logger.info(f"error parsing already saved cert: {e}")
raise ErrorParsingSSLCert(e) from e
try:
x.check_date()
except x509.CertificateError as e:
self.logger.info(f"certificate has expired: {e}")
os.unlink(self.cert_path) # delete pinned cert only in this case
return False
self._verify_certificate_fingerprint(bytearray(b))
return True
async def _get_ssl_context(self):
if self.protocol != 's':
# using plaintext TCP
return None
# see if we already have cert for this server; or get it for the first time
ca_sslc = ssl.create_default_context(purpose=ssl.Purpose.SERVER_AUTH, cafile=ca_path)
if not self._is_saved_ssl_cert_available():
try:
await self._try_saving_ssl_cert_for_first_time(ca_sslc)
except (OSError, ConnectError, aiorpcx.socks.SOCKSError) as e:
raise ErrorGettingSSLCertFromServer(e) from e
# now we have a file saved in our certificate store
siz = os.stat(self.cert_path).st_size
if siz == 0:
# CA signed cert
sslc = ca_sslc
else:
# pinned self-signed cert
sslc = ssl.create_default_context(ssl.Purpose.SERVER_AUTH, cafile=self.cert_path)
sslc.check_hostname = 0
return sslc
def handle_disconnect(func):
async def wrapper_func(self: 'Interface', *args, **kwargs):
try:
return await func(self, *args, **kwargs)
except GracefulDisconnect as e:
self.logger.log(e.log_level, f"disconnecting due to {repr(e)}")
except aiorpcx.jsonrpc.RPCError as e:
self.logger.warning(f"disconnecting due to {repr(e)}")
self.logger.debug(f"(disconnect) trace for {repr(e)}", exc_info=True)
finally:
await self.network.connection_down(self)
if not self.got_disconnected.done():
self.got_disconnected.set_result(1)
# if was not 'ready' yet, schedule waiting coroutines:
self.ready.cancel()
return wrapper_func
@ignore_exceptions # do not kill network.taskgroup
@log_exceptions
@handle_disconnect
async def run(self):
try:
ssl_context = await self._get_ssl_context()
except (ErrorParsingSSLCert, ErrorGettingSSLCertFromServer) as e:
self.logger.info(f'disconnecting due to: {repr(e)}')
return
try:
await self.open_session(ssl_context)
except (asyncio.CancelledError, ConnectError, aiorpcx.socks.SOCKSError) as e:
# make SSL errors for main interface more visible (to help servers ops debug cert pinning issues)
if (isinstance(e, ConnectError) and isinstance(e.__cause__, ssl.SSLError)
and self.is_main_server() and not self.network.auto_connect):
self.logger.warning(f'Cannot connect to main server due to SSL error '
f'(maybe cert changed compared to "{self.cert_path}"). Exc: {repr(e)}')
else:
self.logger.info(f'disconnecting due to: {repr(e)}')
return
def _mark_ready(self) -> None:
if self.ready.cancelled():
raise GracefulDisconnect('conn establishment was too slow; *ready* future was cancelled')
if self.ready.done():
return
assert self.tip_header
chain = blockchain.check_header(self.tip_header)
if not chain:
self.blockchain = blockchain.get_best_chain()
else:
self.blockchain = chain
assert self.blockchain is not None
self.logger.info(f"set blockchain with height {self.blockchain.height()}")
self.ready.set_result(1)
async def _save_certificate(self) -> None:
if not os.path.exists(self.cert_path):
# we may need to retry this a few times, in case the handshake hasn't completed
for _ in range(10):
dercert = await self._fetch_certificate()
if dercert:
self.logger.info("succeeded in getting cert")
self._verify_certificate_fingerprint(dercert)
with open(self.cert_path, 'w') as f:
cert = ssl.DER_cert_to_PEM_cert(dercert)
# workaround android bug
cert = re.sub("([^\n])-----END CERTIFICATE-----","\\1\n-----END CERTIFICATE-----",cert)
f.write(cert)
# even though close flushes we can't fsync when closed.
# and we must flush before fsyncing, cause flush flushes to OS buffer
# fsync writes to OS buffer to disk
f.flush()
os.fsync(f.fileno())
break
await asyncio.sleep(1)
else:
raise GracefulDisconnect("could not get certificate after 10 tries")
async def _fetch_certificate(self) -> bytes:
sslc = ssl.SSLContext()
async with _RSClient(session_factory=RPCSession,
host=self.host, port=self.port,
ssl=sslc, proxy=self.proxy) as session:
asyncio_transport = session.transport._asyncio_transport # type: asyncio.BaseTransport
ssl_object = asyncio_transport.get_extra_info("ssl_object") # type: ssl.SSLObject
return ssl_object.getpeercert(binary_form=True)
def _get_expected_fingerprint(self) -> Optional[str]:
if self.is_main_server():
return self.network.config.get("serverfingerprint")
def _verify_certificate_fingerprint(self, certificate):
expected_fingerprint = self._get_expected_fingerprint()
if not expected_fingerprint:
return
fingerprint = hashlib.sha256(certificate).hexdigest()
fingerprints_match = fingerprint.lower() == expected_fingerprint.lower()
if not fingerprints_match:
util.trigger_callback('cert_mismatch')
raise ErrorSSLCertFingerprintMismatch('Refusing to connect to server due to cert fingerprint mismatch')
self.logger.info("cert fingerprint verification passed")
async def get_block_header(self, height, assert_mode):
self.logger.info(f'requesting block header {height} in mode {assert_mode}')
# use lower timeout as we usually have network.bhi_lock here
timeout = self.network.get_network_timeout_seconds(NetworkTimeout.Urgent)
res = await self.session.send_request('blockchain.block.header', [height], timeout=timeout)
return blockchain.deserialize_header(bytes.fromhex(res), height)
async def request_chunk(self, height: int, tip=None, *, can_return_early=False):
if not is_non_negative_integer(height):
raise Exception(f"{repr(height)} is not a block height")
index = height // 2016
if can_return_early and index in self._requested_chunks:
return
self.logger.info(f"requesting chunk from height {height}")
size = 2016
if tip is not None:
size = min(size, tip - index * 2016 + 1)
size = max(size, 0)
try:
self._requested_chunks.add(index)
res = await self.session.send_request('blockchain.block.headers', [index * 2016, size])
finally:
self._requested_chunks.discard(index)
assert_dict_contains_field(res, field_name='count')
assert_dict_contains_field(res, field_name='hex')
assert_dict_contains_field(res, field_name='max')
assert_non_negative_integer(res['count'])
assert_non_negative_integer(res['max'])
assert_hex_str(res['hex'])
if len(res['hex']) != HEADER_SIZE * 2 * res['count']:
raise RequestCorrupted('inconsistent chunk hex and count')
if res['count'] != size:
raise RequestCorrupted(f"expected {size} headers but only got {res['count']}")
conn = self.blockchain.connect_chunk(index, res['hex'])
if not conn:
return conn, 0
return conn, res['count']
def is_main_server(self) -> bool:
return (self.network.interface == self or
self.network.interface is None and self.network.default_server == self.server)
async def open_session(self, sslc, exit_early=False):
session_factory = lambda *args, iface=self, **kwargs: NotificationSession(*args, **kwargs, interface=iface)
async with _RSClient(session_factory=session_factory,
host=self.host, port=self.port,
ssl=sslc, proxy=self.proxy) as session:
self.session = session # type: NotificationSession
self.session.set_default_timeout(self.network.get_network_timeout_seconds(NetworkTimeout.Generic))
try:
ver = await session.send_request('server.version', [self.client_name(), version.PROTOCOL_VERSION])
except aiorpcx.jsonrpc.RPCError as e:
raise GracefulDisconnect(e) # probably 'unsupported protocol version'
if exit_early:
return
if ver[1] != version.PROTOCOL_VERSION:
raise GracefulDisconnect(f'server violated protocol-version-negotiation. '
f'we asked for {version.PROTOCOL_VERSION!r}, they sent {ver[1]!r}')
if not self.network.check_interface_against_healthy_spread_of_connected_servers(self):
raise GracefulDisconnect(f'too many connected servers already '
f'in bucket {self.bucket_based_on_ipaddress()}')
self.logger.info(f"connection established. version: {ver}")
try:
async with self.taskgroup as group:
await group.spawn(self.ping)
await group.spawn(self.request_fee_estimates)
await group.spawn(self.run_fetch_blocks)
await group.spawn(self.monitor_connection)
except aiorpcx.jsonrpc.RPCError as e:
if e.code in (JSONRPC.EXCESSIVE_RESOURCE_USAGE,
JSONRPC.SERVER_BUSY,
JSONRPC.METHOD_NOT_FOUND):
raise GracefulDisconnect(e, log_level=logging.WARNING) from e
raise
async def monitor_connection(self):
while True:
await asyncio.sleep(1)
if not self.session or self.session.is_closing():
raise GracefulDisconnect('session was closed')
async def ping(self):
while True:
await asyncio.sleep(300)
await self.session.send_request('server.ping')
async def request_fee_estimates(self):
from .simple_config import FEE_ETA_TARGETS
while True:
async with TaskGroup() as group:
fee_tasks = []
for i in FEE_ETA_TARGETS:
fee_tasks.append((i, await group.spawn(self.get_estimatefee(i))))
for nblock_target, task in fee_tasks:
fee = task.result()
if fee < 0: continue
self.fee_estimates_eta[nblock_target] = fee
self.network.update_fee_estimates()
await asyncio.sleep(60)
async def close(self):
"""Closes the connection and waits for it to be closed.
We try to flush buffered data to the wire, so this can take some time.
"""
if self.session:
await self.session.close()
# monitor_connection will cancel tasks
async def run_fetch_blocks(self):
header_queue = asyncio.Queue()
await self.session.subscribe('blockchain.headers.subscribe', [], header_queue)
while True:
item = await header_queue.get()
raw_header = item[0]
height = raw_header['height']
header = blockchain.deserialize_header(bfh(raw_header['hex']), height)
self.tip_header = header
self.tip = height
if self.tip < constants.net.max_checkpoint():
raise GracefulDisconnect('server tip below max checkpoint')
self._mark_ready()
await self._process_header_at_tip()
# header processing done
util.trigger_callback('blockchain_updated')
util.trigger_callback('network_updated')
await self.network.switch_unwanted_fork_interface()
await self.network.switch_lagging_interface()
async def _process_header_at_tip(self):
height, header = self.tip, self.tip_header
async with self.network.bhi_lock:
if self.blockchain.height() >= height and self.blockchain.check_header(header):
# another interface amended the blockchain
self.logger.info(f"skipping header {height}")
return
_, height = await self.step(height, header)
# in the simple case, height == self.tip+1
if height <= self.tip:
await self.sync_until(height)
async def sync_until(self, height, next_height=None):
if next_height is None:
next_height = self.tip
last = None
while last is None or height <= next_height:
prev_last, prev_height = last, height
if next_height > height + 10:
could_connect, num_headers = await self.request_chunk(height, next_height)
if not could_connect:
if height <= constants.net.max_checkpoint():
raise GracefulDisconnect('server chain conflicts with checkpoints or genesis')
last, height = await self.step(height)
continue
util.trigger_callback('network_updated')
height = (height // 2016 * 2016) + num_headers
assert height <= next_height+1, (height, self.tip)
last = 'catchup'
else:
last, height = await self.step(height)
assert (prev_last, prev_height) != (last, height), 'had to prevent infinite loop in interface.sync_until'
return last, height
async def step(self, height, header=None):
assert 0 <= height <= self.tip, (height, self.tip)
if header is None:
header = await self.get_block_header(height, 'catchup')
chain = blockchain.check_header(header) if 'mock' not in header else header['mock']['check'](header)
if chain:
self.blockchain = chain if isinstance(chain, Blockchain) else self.blockchain
# note: there is an edge case here that is not handled.
# we might know the blockhash (enough for check_header) but
# not have the header itself. e.g. regtest chain with only genesis.
# this situation resolves itself on the next block
return 'catchup', height+1
can_connect = blockchain.can_connect(header) if 'mock' not in header else header['mock']['connect'](height)
if not can_connect:
self.logger.info(f"can't connect {height}")
height, header, bad, bad_header = await self._search_headers_backwards(height, header)
chain = blockchain.check_header(header) if 'mock' not in header else header['mock']['check'](header)
can_connect = blockchain.can_connect(header) if 'mock' not in header else header['mock']['connect'](height)
assert chain or can_connect
if can_connect:
self.logger.info(f"could connect {height}")
height += 1
if isinstance(can_connect, Blockchain): # not when mocking
self.blockchain = can_connect
self.blockchain.save_header(header)
return 'catchup', height
good, bad, bad_header = await self._search_headers_binary(height, bad, bad_header, chain)
return await self._resolve_potential_chain_fork_given_forkpoint(good, bad, bad_header)
async def _search_headers_binary(self, height, bad, bad_header, chain):
assert bad == bad_header['block_height']
_assert_header_does_not_check_against_any_chain(bad_header)
self.blockchain = chain if isinstance(chain, Blockchain) else self.blockchain
good = height
while True:
assert good < bad, (good, bad)
height = (good + bad) // 2
self.logger.info(f"binary step. good {good}, bad {bad}, height {height}")
header = await self.get_block_header(height, 'binary')
chain = blockchain.check_header(header) if 'mock' not in header else header['mock']['check'](header)
if chain:
self.blockchain = chain if isinstance(chain, Blockchain) else self.blockchain
good = height
else:
bad = height
bad_header = header
if good + 1 == bad:
break
mock = 'mock' in bad_header and bad_header['mock']['connect'](height)
real = not mock and self.blockchain.can_connect(bad_header, check_height=False)
if not real and not mock:
raise Exception('unexpected bad header during binary: {}'.format(bad_header))
_assert_header_does_not_check_against_any_chain(bad_header)
self.logger.info(f"binary search exited. good {good}, bad {bad}")
return good, bad, bad_header
async def _resolve_potential_chain_fork_given_forkpoint(self, good, bad, bad_header):
assert good + 1 == bad
assert bad == bad_header['block_height']
_assert_header_does_not_check_against_any_chain(bad_header)
# 'good' is the height of a block 'good_header', somewhere in self.blockchain.
# bad_header connects to good_header; bad_header itself is NOT in self.blockchain.
bh = self.blockchain.height()
assert bh >= good, (bh, good)
if bh == good:
height = good + 1
self.logger.info(f"catching up from {height}")
return 'no_fork', height
# this is a new fork we don't yet have
height = bad + 1
self.logger.info(f"new fork at bad height {bad}")
forkfun = self.blockchain.fork if 'mock' not in bad_header else bad_header['mock']['fork']
b = forkfun(bad_header) # type: Blockchain
self.blockchain = b
assert b.forkpoint == bad
return 'fork', height
async def _search_headers_backwards(self, height, header):
async def iterate():
nonlocal height, header
checkp = False
if height <= constants.net.max_checkpoint():
height = constants.net.max_checkpoint()
checkp = True
header = await self.get_block_header(height, 'backward')
chain = blockchain.check_header(header) if 'mock' not in header else header['mock']['check'](header)
can_connect = blockchain.can_connect(header) if 'mock' not in header else header['mock']['connect'](height)
if chain or can_connect:
return False
if checkp:
raise GracefulDisconnect("server chain conflicts with checkpoints")
return True
bad, bad_header = height, header
_assert_header_does_not_check_against_any_chain(bad_header)
with blockchain.blockchains_lock: chains = list(blockchain.blockchains.values())
local_max = max([0] + [x.height() for x in chains]) if 'mock' not in header else float('inf')
height = min(local_max + 1, height - 1)
while await iterate():
bad, bad_header = height, header
delta = self.tip - height
height = self.tip - 2 * delta
_assert_header_does_not_check_against_any_chain(bad_header)
self.logger.info(f"exiting backward mode at {height}")
return height, header, bad, bad_header
@classmethod
def client_name(cls) -> str:
return f'electrum/{version.ELECTRUM_VERSION}'
def is_tor(self):
return self.host.endswith('.onion')
def ip_addr(self) -> Optional[str]:
session = self.session
if not session: return None
peer_addr = session.remote_address()
if not peer_addr: return None
return str(peer_addr.host)
def bucket_based_on_ipaddress(self) -> str:
def do_bucket():
if self.is_tor():
return BUCKET_NAME_OF_ONION_SERVERS
try:
ip_addr = ip_address(self.ip_addr()) # type: Union[IPv4Address, IPv6Address]
except ValueError:
return ''
if not ip_addr:
return ''
if ip_addr.is_loopback: # localhost is exempt
return ''
if ip_addr.version == 4:
slash16 = IPv4Network(ip_addr).supernet(prefixlen_diff=32-16)
return str(slash16)
elif ip_addr.version == 6:
slash48 = IPv6Network(ip_addr).supernet(prefixlen_diff=128-48)
return str(slash48)
return ''
if not self._ipaddr_bucket:
self._ipaddr_bucket = do_bucket()
return self._ipaddr_bucket
async def get_merkle_for_transaction(self, tx_hash: str, tx_height: int) -> dict:
if not is_hash256_str(tx_hash):
raise Exception(f"{repr(tx_hash)} is not a txid")
if not is_non_negative_integer(tx_height):
raise Exception(f"{repr(tx_height)} is not a block height")
# do request
res = await self.session.send_request('blockchain.transaction.get_merkle', [tx_hash, tx_height])
# check response
block_height = assert_dict_contains_field(res, field_name='block_height')
merkle = assert_dict_contains_field(res, field_name='merkle')
pos = assert_dict_contains_field(res, field_name='pos')
# note: tx_height was just a hint to the server, don't enforce the response to match it
assert_non_negative_integer(block_height)
assert_non_negative_integer(pos)
assert_list_or_tuple(merkle)
for item in merkle:
assert_hash256_str(item)
return res
async def get_transaction(self, tx_hash: str, *, timeout=None) -> str:
if not is_hash256_str(tx_hash):
raise Exception(f"{repr(tx_hash)} is not a txid")
raw = await self.session.send_request('blockchain.transaction.get', [tx_hash], timeout=timeout)
# validate response
tx = Transaction(raw)
try:
tx.deserialize() # see if raises
except Exception as e:
raise RequestCorrupted(f"cannot deserialize received transaction (txid {tx_hash})") from e
if tx.txid() != tx_hash:
raise RequestCorrupted(f"received tx does not match expected txid {tx_hash} (got {tx.txid()})")
return raw
async def get_history_for_scripthash(self, sh: str) -> List[dict]:
if not is_hash256_str(sh):
raise Exception(f"{repr(sh)} is not a scripthash")
# do request
res = await self.session.send_request('blockchain.scripthash.get_history', [sh])
# check response
assert_list_or_tuple(res)
for tx_item in res:
assert_dict_contains_field(tx_item, field_name='height')
assert_dict_contains_field(tx_item, field_name='tx_hash')
assert_integer(tx_item['height'])
assert_hash256_str(tx_item['tx_hash'])
if tx_item['height'] in (-1, 0):
assert_dict_contains_field(tx_item, field_name='fee')
assert_non_negative_integer(tx_item['fee'])
return res
async def listunspent_for_scripthash(self, sh: str) -> List[dict]:
if not is_hash256_str(sh):
raise Exception(f"{repr(sh)} is not a scripthash")
# do request
res = await self.session.send_request('blockchain.scripthash.listunspent', [sh])
# check response
assert_list_or_tuple(res)
for utxo_item in res:
assert_dict_contains_field(utxo_item, field_name='tx_pos')
assert_dict_contains_field(utxo_item, field_name='value')
assert_dict_contains_field(utxo_item, field_name='tx_hash')
assert_dict_contains_field(utxo_item, field_name='height')
assert_non_negative_integer(utxo_item['tx_pos'])
assert_non_negative_integer(utxo_item['value'])
assert_non_negative_integer(utxo_item['height'])
assert_hash256_str(utxo_item['tx_hash'])
return res
async def get_balance_for_scripthash(self, sh: str) -> dict:
if not is_hash256_str(sh):
raise Exception(f"{repr(sh)} is not a scripthash")
# do request
res = await self.session.send_request('blockchain.scripthash.get_balance', [sh])
# check response
assert_dict_contains_field(res, field_name='confirmed')
assert_dict_contains_field(res, field_name='unconfirmed')
assert_non_negative_integer(res['confirmed'])
assert_non_negative_integer(res['unconfirmed'])
return res
async def get_txid_from_txpos(self, tx_height: int, tx_pos: int, merkle: bool):
if not is_non_negative_integer(tx_height):
raise Exception(f"{repr(tx_height)} is not a block height")
if not is_non_negative_integer(tx_pos):
raise Exception(f"{repr(tx_pos)} should be non-negative integer")
# do request
res = await self.session.send_request(
'blockchain.transaction.id_from_pos',
[tx_height, tx_pos, merkle],
)
# check response
if merkle:
assert_dict_contains_field(res, field_name='tx_hash')
assert_dict_contains_field(res, field_name='merkle')
assert_hash256_str(res['tx_hash'])
assert_list_or_tuple(res['merkle'])
for node_hash in res['merkle']:
assert_hash256_str(node_hash)
else:
assert_hash256_str(res)
return res
async def get_fee_histogram(self) -> Sequence[Tuple[Union[float, int], int]]:
# do request
res = await self.session.send_request('mempool.get_fee_histogram')
# check response
assert_list_or_tuple(res)
prev_fee = float('inf')
for fee, s in res:
assert_non_negative_int_or_float(fee)
assert_non_negative_integer(s)
if fee >= prev_fee: # check monotonicity
raise RequestCorrupted(f'fees must be in decreasing order')
prev_fee = fee
return res
async def get_server_banner(self) -> str:
# do request
res = await self.session.send_request('server.banner')
# check response
if not isinstance(res, str):
raise RequestCorrupted(f'{res!r} should be a str')
return res
async def get_donation_address(self) -> str:
# do request
res = await self.session.send_request('server.donation_address')
# check response
if not res: # ignore empty string
return ''
if not bitcoin.is_address(res):
# note: do not hard-fail -- allow server to use future-type
# bitcoin address we do not recognize
self.logger.info(f"invalid donation address from server: {repr(res)}")
res = ''
return res
async def get_relay_fee(self) -> int:
"""Returns the min relay feerate in sat/kbyte."""
# do request
res = await self.session.send_request('blockchain.relayfee')
# check response
assert_non_negative_int_or_float(res)
relayfee = int(res * bitcoin.COIN)
relayfee = max(0, relayfee)
return relayfee
async def get_estimatefee(self, num_blocks: int) -> int:
"""Returns a feerate estimate for getting confirmed within
num_blocks blocks, in sat/kbyte.
"""
if not is_non_negative_integer(num_blocks):
raise Exception(f"{repr(num_blocks)} is not a num_blocks")
# do request
res = await self.session.send_request('blockchain.estimatefee', [num_blocks])
# check response
if res != -1:
assert_non_negative_int_or_float(res)
res = int(res * bitcoin.COIN)
return res
def _assert_header_does_not_check_against_any_chain(header: dict) -> None:
chain_bad = blockchain.check_header(header) if 'mock' not in header else header['mock']['check'](header)
if chain_bad:
raise Exception('bad_header must not check!')
def check_cert(host, cert):
try:
b = pem.dePem(cert, 'CERTIFICATE')
x = x509.X509(b)
except:
traceback.print_exc(file=sys.stdout)
return
try:
x.check_date()
expired = False
except:
expired = True
m = "host: %s\n"%host
m += "has_expired: %s\n"% expired
util.print_msg(m)
# Used by tests
def _match_hostname(name, val):
if val == name:
return True
return val.startswith('*.') and name.endswith(val[1:])
def test_certificates():
from .simple_config import SimpleConfig
config = SimpleConfig()
mydir = os.path.join(config.path, "certs")
certs = os.listdir(mydir)
for c in certs:
p = os.path.join(mydir,c)
with open(p, encoding='utf-8') as f:
cert = f.read()
check_cert(c, cert)
if __name__ == "__main__":
test_certificates()