# Copyright (c) 2016, Neil Booth
#
# All rights reserved.
#
# See the file "LICENCE" for information about the copyright
# and warranty status of this software.
'''Class for handling environment configuration and defaults.'''
import resource
from collections import namedtuple
from ipaddress import ip_address
from lib.coins import Coin
from lib.env_base import EnvBase
import lib.util as lib_util
import server.version as version
NetIdentity = namedtuple('NetIdentity', 'host tcp_port ssl_port nick_suffix')
class Env(EnvBase):
'''Wraps environment configuration.'''
# Peer discovery
PD_OFF, PD_SELF, PD_ON = range(3)
def __init__(self):
super().__init__()
self.obsolete(['UTXO_MB', 'HIST_MB', 'NETWORK'])
self.db_dir = self.required('DB_DIRECTORY')
self.db_engine = self.default('DB_ENGINE', 'leveldb')
self.daemon_url = self.required('DAEMON_URL')
coin_name = self.required('COIN').strip()
network = self.default('NET', 'mainnet').strip()
self.coin = Coin.lookup_coin_class(coin_name, network)
self.cache_MB = self.integer('CACHE_MB', 1200)
self.host = self.default('HOST', 'localhost')
self.reorg_limit = self.integer('REORG_LIMIT', self.coin.REORG_LIMIT)
# Server stuff
self.tcp_port = self.integer('TCP_PORT', None)
self.ssl_port = self.integer('SSL_PORT', None)
if self.ssl_port:
self.ssl_certfile = self.required('SSL_CERTFILE')
self.ssl_keyfile = self.required('SSL_KEYFILE')
self.rpc_port = self.integer('RPC_PORT', 8000)
self.max_subscriptions = self.integer('MAX_SUBSCRIPTIONS', 10000)
self.banner_file = self.default('BANNER_FILE', None)
self.tor_banner_file = self.default('TOR_BANNER_FILE',
self.banner_file)
self.anon_logs = self.boolean('ANON_LOGS', False)
self.log_sessions = self.integer('LOG_SESSIONS', 3600)
# Peer discovery
self.peer_discovery = self.peer_discovery_enum()
self.peer_announce = self.boolean('PEER_ANNOUNCE', True)
self.force_proxy = self.boolean('FORCE_PROXY', False)
self.tor_proxy_host = self.default('TOR_PROXY_HOST', 'localhost')
self.tor_proxy_port = self.integer('TOR_PROXY_PORT', None)
# The electrum client takes the empty string as unspecified
self.donation_address = self.default('DONATION_ADDRESS', '')
# Server limits to help prevent DoS
self.max_send = self.integer('MAX_SEND', 1000000)
self.max_subs = self.integer('MAX_SUBS', 250000)
self.max_sessions = self.sane_max_sessions()
self.max_session_subs = self.integer('MAX_SESSION_SUBS', 50000)
self.bandwidth_limit = self.integer('BANDWIDTH_LIMIT', 2000000)
self.session_timeout = self.integer('SESSION_TIMEOUT', 600)
# Identities
clearnet_identity = self.clearnet_identity()
tor_identity = self.tor_identity(clearnet_identity)
self.identities = [identity
for identity in (clearnet_identity, tor_identity)
if identity is not None]
def sane_max_sessions(self):
'''Return the maximum number of sessions to permit. Normally this
is MAX_SESSIONS. However, to prevent open file exhaustion, ajdust
downwards if running with a small open file rlimit.'''
env_value = self.integer('MAX_SESSIONS', 1000)
nofile_limit = resource.getrlimit(resource.RLIMIT_NOFILE)[0]
# We give the DB 250 files; allow ElectrumX 100 for itself
value = max(0, min(env_value, nofile_limit - 350))
if value < env_value:
self.log_warning('lowered maximum sessions from {:,d} to {:,d} '
'because your open file limit is {:,d}'
.format(env_value, value, nofile_limit))
return value
def clearnet_identity(self):
host = self.default('REPORT_HOST', None)
if host is None:
return None
try:
ip = ip_address(host)
except ValueError:
bad = (not lib_util.is_valid_hostname(host)
or host.lower() == 'localhost')
else:
bad = (ip.is_multicast or ip.is_unspecified
or (ip.is_private and self.peer_announce))
if bad:
raise self.Error('"{}" is not a valid REPORT_HOST'.format(host))
tcp_port = self.integer('REPORT_TCP_PORT', self.tcp_port) or None
ssl_port = self.integer('REPORT_SSL_PORT', self.ssl_port) or None
if tcp_port == ssl_port:
raise self.Error('REPORT_TCP_PORT and REPORT_SSL_PORT '
'both resolve to {}'.format(tcp_port))
return NetIdentity(
host,
tcp_port,
ssl_port,
''
)
def tor_identity(self, clearnet):
host = self.default('REPORT_HOST_TOR', None)
if host is None:
return None
if not host.endswith('.onion'):
raise self.Error('tor host "{}" must end with ".onion"'
.format(host))
def port(port_kind):
'''Returns the clearnet identity port, if any and not zero,
otherwise the listening port.'''
result = 0
if clearnet:
result = getattr(clearnet, port_kind)
return result or getattr(self, port_kind)
tcp_port = self.integer('REPORT_TCP_PORT_TOR', port('tcp_port')) or None
ssl_port = self.integer('REPORT_SSL_PORT_TOR', port('ssl_port')) or None
if tcp_port == ssl_port:
raise self.Error('REPORT_TCP_PORT_TOR and REPORT_SSL_PORT_TOR '
'both resolve to {}'.format(tcp_port))
return NetIdentity(
host,
tcp_port,
ssl_port,
'_tor',
)
def server_features(self):
'''Return the server features dictionary.'''
hosts = {identity.host: {'tcp_port': identity.tcp_port,
'ssl_port': identity.ssl_port}
for identity in self.identities}
return {
'hosts': hosts,
'pruning': None,
'server_version': version.VERSION,
'protocol_min': version.PROTOCOL_MIN,
'protocol_max': version.PROTOCOL_MAX,
'genesis_hash': self.coin.GENESIS_HASH,
'hash_function': 'sha256',
}
def peer_discovery_enum(self):
pd = self.default('PEER_DISCOVERY', 'on').strip().lower()
if pd in ('off', ''):
return self.PD_OFF
elif pd == 'self':
return self.PD_SELF
else:
return self.PD_ON