flo-electrum/lib/interface.py

380 lines
14 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.
import aiosocks
import os
import stat
import re
import ssl
import sys
import threading
import time
import traceback
import asyncio
import json
import asyncio.streams
from asyncio.sslproto import SSLProtocol
import io
import requests
from aiosocks.errors import SocksError
from concurrent.futures import TimeoutError
ca_path = requests.certs.where()
from .util import print_error
from .ssl_in_socks import sslInSocksReaderWriter
from . import util
from . import x509
from . import pem
def get_ssl_context(cert_reqs, ca_certs):
context = ssl.create_default_context(purpose=ssl.Purpose.SERVER_AUTH, cafile=ca_certs)
context.check_hostname = False
context.verify_mode = cert_reqs
context.options |= ssl.OP_NO_SSLv2
context.options |= ssl.OP_NO_SSLv3
context.options |= ssl.OP_NO_TLSv1
return context
class Interface(util.PrintError):
"""The Interface class handles a socket connected to a single remote
electrum server. It's exposed API is:
- Member functions close(), fileno(), get_response(), has_timed_out(),
ping_required(), queue_request(), send_request()
- Member variable server.
"""
def __init__(self, server, config_path, proxy_config, is_running):
self.is_running = is_running
self.addr = self.auth = None
if proxy_config is not None:
if proxy_config["mode"] == "socks5":
self.addr = aiosocks.Socks5Addr(proxy_config["host"], proxy_config["port"])
self.auth = aiosocks.Socks5Auth(proxy_config["user"], proxy_config["password"]) if proxy_config["user"] != "" else None
elif proxy_config["mode"] == "socks4":
self.addr = aiosocks.Socks4Addr(proxy_config["host"], proxy_config["port"])
self.auth = aiosocks.Socks4Auth(proxy_config["password"]) if proxy_config["password"] != "" else None
else:
raise Exception("proxy mode not supported")
self.server = server
self.config_path = config_path
host, port, protocol = self.server.split(':')
self.host = host
self.port = int(port)
self.use_ssl = (protocol=='s')
self.reader = self.writer = None
self.lock = asyncio.Lock()
# Dump network messages. Set at runtime from the console.
self.debug = False
self.unsent_requests = asyncio.PriorityQueue()
self.unanswered_requests = {}
self.last_ping = 0
self.closed_remotely = False
self.buf = bytes()
def conn_coro(self, context):
return asyncio.open_connection(self.host, self.port, ssl=context)
async def _save_certificate(self, cert_path, require_ca):
dercert = None
if require_ca:
context = get_ssl_context(cert_reqs=ssl.CERT_REQUIRED, ca_certs=ca_path)
else:
context = get_ssl_context(cert_reqs=ssl.CERT_NONE, ca_certs=None)
try:
if self.addr is not None:
proto_factory = lambda: SSLProtocol(asyncio.get_event_loop(), asyncio.Protocol(), context, None)
socks_create_coro = aiosocks.create_connection(proto_factory, \
proxy=self.addr, \
proxy_auth=self.auth, \
dst=(self.host, self.port))
transport, protocol = await asyncio.wait_for(socks_create_coro, 5)
async def job(fut):
try:
if protocol._sslpipe is not None:
fut.set_result(protocol._sslpipe.ssl_object.getpeercert(True))
except BaseException as e:
fut.set_exception(e)
while self.is_running():
fut = asyncio.Future()
asyncio.ensure_future(job(fut))
try:
await fut
except:
pass
try:
fut.exception()
dercert = fut.result()
except ValueError:
await asyncio.sleep(1)
continue
except:
if self.is_running():
traceback.print_exc()
print("Previous exception from _save_certificate")
continue
break
if not self.is_running(): return
transport.close()
else:
reader, writer = await asyncio.wait_for(self.conn_coro(context), 3)
dercert = writer.get_extra_info('ssl_object').getpeercert(True)
writer.close()
except OSError as e: # not ConnectionError because we need socket.gaierror too
if self.is_running():
self.print_error(self.server, "Exception in _save_certificate", type(e))
return
except TimeoutError:
return
assert dercert
if not require_ca:
cert = ssl.DER_cert_to_PEM_cert(dercert)
else:
# Don't pin a CA signed certificate
cert = ""
temporary_path = cert_path + '.temp'
with open(temporary_path, "w") as f:
f.write(cert)
return temporary_path
async def _get_read_write(self):
async with self.lock:
if self.reader is not None and self.writer is not None:
return self.reader, self.writer, True
if self.use_ssl:
cert_path = os.path.join(self.config_path, 'certs', self.host)
if not os.path.exists(cert_path):
temporary_path = await self._save_certificate(cert_path, True)
if not temporary_path:
temporary_path = await self._save_certificate(cert_path, False)
if not temporary_path:
raise ConnectionError("Could not get certificate on second try")
is_new = True
else:
is_new = False
ca_certs = temporary_path if is_new else cert_path
size = os.stat(ca_certs)[stat.ST_SIZE]
self_signed = size != 0
if not self_signed:
ca_certs = ca_path
try:
if self.addr is not None:
if not self.use_ssl:
open_coro = aiosocks.open_connection(proxy=self.addr, proxy_auth=self.auth, dst=(self.host, self.port))
self.reader, self.writer = await asyncio.wait_for(open_coro, 5)
else:
ssl_in_socks_coro = sslInSocksReaderWriter(self.addr, self.auth, self.host, self.port, ca_certs)
self.reader, self.writer = await asyncio.wait_for(ssl_in_socks_coro, 5)
else:
context = get_ssl_context(cert_reqs=ssl.CERT_REQUIRED, ca_certs=ca_certs) if self.use_ssl else None
self.reader, self.writer = await asyncio.wait_for(self.conn_coro(context), 5)
except TimeoutError:
self.print_error("TimeoutError after getting certificate successfully...")
raise
except BaseException as e:
if self.is_running():
if not isinstance(e, OSError):
traceback.print_exc()
self.print_error("Previous exception will now be reraised")
raise e
if self.use_ssl and is_new:
self.print_error("saving new certificate for", self.host)
os.rename(temporary_path, cert_path)
return self.reader, self.writer, False
async def send_all(self, list_of_requests):
_, w, usedExisting = await self._get_read_write()
starttime = time.time()
for i in list_of_requests:
w.write(json.dumps(i).encode("ascii") + b"\n")
await w.drain()
if time.time() - starttime > 2.5:
self.print_error("send_all: sending is taking too long. Used existing connection: ", usedExisting)
raise ConnectionError("sending is taking too long")
def close(self):
if self.writer:
self.writer.close()
def _try_extract(self):
try:
pos = self.buf.index(b"\n")
except ValueError:
return
obj = self.buf[:pos]
try:
obj = json.loads(obj.decode("ascii"))
except ValueError:
return
else:
self.buf = self.buf[pos+1:]
self.last_action = time.time()
return obj
async def get(self):
reader, _, _ = await self._get_read_write()
while self.is_running():
tried = self._try_extract()
if tried: return tried
temp = io.BytesIO()
try:
data = await asyncio.wait_for(reader.read(2**10), 1)
temp.write(data)
except asyncio.TimeoutError:
continue
self.buf += temp.getvalue()
def idle_time(self):
return time.time() - self.last_action
def diagnostic_name(self):
return self.host
async def queue_request(self, *args): # method, params, _id
'''Queue a request, later to be send with send_requests when the
socket is available for writing.
'''
self.request_time = time.time()
await self.unsent_requests.put((self.request_time, args))
def num_requests(self):
'''Keep unanswered requests below 100'''
n = 100 - len(self.unanswered_requests)
return min(n, self.unsent_requests.qsize())
async def send_request(self):
'''Sends queued requests. Returns False on failure.'''
make_dict = lambda m, p, i: {'method': m, 'params': p, 'id': i}
n = self.num_requests()
try:
prio, request = await asyncio.wait_for(self.unsent_requests.get(), 1.5)
except TimeoutError:
return False
try:
await self.send_all([make_dict(*request)])
except (SocksError, OSError, TimeoutError) as e:
if type(e) is SocksError:
self.print_error(e)
await self.unsent_requests.put((prio, request))
return False
if self.debug:
self.print_error("-->", request)
self.unanswered_requests[request[2]] = request
self.last_action = time.time()
return True
def ping_required(self):
'''Maintains time since last ping. Returns True if a ping should
be sent.
'''
now = time.time()
if now - self.last_ping > 60:
self.last_ping = now
return True
return False
def has_timed_out(self):
'''Returns True if the interface has timed out.'''
if (self.unanswered_requests and time.time() - self.request_time > 10
and self.idle_time() > 10):
self.print_error("timeout", len(self.unanswered_requests))
return True
return False
async def get_response(self):
'''Call if there is data available on the socket. Returns a list of
(request, response) pairs. Notifications are singleton
unsolicited responses presumably as a result of prior
subscriptions, so request is None and there is no 'id' member.
Otherwise it is a response, which has an 'id' member and a
corresponding request. If the connection was closed remotely
or the remote server is misbehaving, a (None, None) will appear.
'''
response = await self.get()
if not type(response) is dict:
if response is None:
self.closed_remotely = True
if self.is_running():
self.print_error("connection closed remotely")
return None, None
if self.debug:
self.print_error("<--", response)
wire_id = response.get('id', None)
if wire_id is None: # Notification
return None, response
else:
request = self.unanswered_requests.pop(wire_id, None)
if request:
return request, response
else:
self.print_error("unknown wire ID", wire_id)
return None, None # Signal
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) as f:
cert = f.read()
check_cert(c, cert)
if __name__ == "__main__":
test_certificates()