def get_servers(CFG):
"""
Given a configuration file, instantiate and return a list of enabled
servers.
"""
servers = []
if (CFG.has_section('telnet') and
(not CFG.has_option('telnet', 'enabled')
or CFG.getboolean('telnet', 'enabled'))):
# start telnet server instance
from x84.telnet import TelnetServer
servers.append(TelnetServer(config=CFG))
if (CFG.has_section('ssh') and
not CFG.has_option('ssh', 'enabled')
or CFG.getboolean('ssh', 'enabled')):
# start ssh server instance
#
# may raise an ImportError for systems where pyOpenSSL and etc. could
# not be installed (due to any issues with missing python-dev, libffi,
# cc, etc.). Allow it to raise naturally, the curious user should
# either discover and resolve the root issue, or disable ssh if it
# cannot be resolved.
from x84.ssh import SshServer
servers.append(SshServer(config=CFG))
if (CFG.has_section('rlogin') and
(not CFG.has_option('rlogin', 'enabled')
or CFG.getboolean('rlogin', 'enabled'))):
# start rlogin server instance
from x84.rlogin import RLoginServer
servers.append(RLoginServer(config=CFG))
return servers
def get_servers(CFG):
""" Instantiate and return enabled servers by configuration ``CFG``. """
servers = []
if (CFG.has_section('telnet') and
(not CFG.has_option('telnet', 'enabled')
or CFG.getboolean('telnet', 'enabled'))):
# start telnet server instance
from x84.telnet import TelnetServer
servers.append(TelnetServer(config=CFG))
if (CFG.has_section('ssh') and
not CFG.has_option('ssh', 'enabled')
or CFG.getboolean('ssh', 'enabled')):
# start ssh server instance
#
# may raise an ImportError for systems where pyOpenSSL and etc. could
# not be installed (due to any issues with missing python-dev, libffi,
# cc, etc.). Allow it to raise naturally, the curious user should
# either discover and resolve the root issue, or disable ssh if it
# cannot be resolved.
from x84.ssh import SshServer
servers.append(SshServer(config=CFG))
if (CFG.has_section('rlogin') and
(not CFG.has_option('rlogin', 'enabled')
or CFG.getboolean('rlogin', 'enabled'))):
# start rlogin server instance
from x84.rlogin import RLoginServer
servers.append(RLoginServer(config=CFG))
return servers
def describe_ssh_availability(term, session):
from x84.bbs.ini import CFG
if session.kind == 'ssh':
# what a good citizen!
return
if not (CFG.has_section('ssh') and not CFG.has_option('ssh', 'enabled')
or CFG.getboolean('ssh', 'enabled')):
# ssh not enabled
return
about_key = (u"You may even use an ssh key, which you can configure from "
u"your user profile, "
if not session.user.get('pubkey') else u'')
big_msg = term.bold_blue("Big Brother is Watching You")
description = (
u"\r\n\r\n"
u" {term.red}You are using {session.kind}, but ssh is available "
u"on port {ssh_port} of this server. If you want a secure connection "
u"with shorter latency, we recommend instead to use ssh! {about_key}"
u"Remember: {big_msg}!\r\n\r\n".format(term=term,
session=session,
ssh_port=ssh_port,
about_key=about_key,
big_msg=big_msg))
show_description(term, description, color=None)
waitprompt(term)
def describe_ssh_availability(term, session):
from x84.bbs.ini import CFG
if session.kind == 'ssh':
# what a good citizen!
return
if not (CFG.has_section('ssh') and
not CFG.has_option('ssh', 'enabled')
or CFG.getboolean('ssh', 'enabled')):
# ssh not enabled
return
about_key = (u"You may even use an ssh key, which you can configure from "
u"your user profile, " if not session.user.get('pubkey')
else u'')
big_msg = term.bold_blue("Big Brother is Watching You")
description = (
u"\r\n\r\n"
u" {term.red}You are using {session.kind}, but ssh is available "
u"on port {ssh_port} of this server. If you want a secure connection "
u"with shorter latency, we recommend instead to use ssh! {about_key}"
u"Remember: {big_msg}!\r\n\r\n".format(
term=term, session=session, ssh_port=ssh_port,
about_key=about_key, big_msg=big_msg))
show_description(term, description, color=None)
waitprompt(term)
def describe_ssh_availability(term, session):
from x84.bbs.ini import CFG
if session.kind == 'ssh':
# what a good citizen!
return
if not (CFG.has_section('ssh') and
not CFG.has_option('ssh', 'enabled')
or CFG.getboolean('ssh', 'enabled')):
# ssh not enabled
return
about_key = (u"You may even use an ssh key, which you can configure from "
u"your user profile, " if not session.user.get('pubkey')
else u'')
big_msg = term.bold_blue("Big Brother is Watching You")
description = (
" {term.red}You are using {session.kind}, but ssh is available "
"on port {ssh_port} of this server. If you want a secure connection "
"with shorter latency, we recommend instead to use ssh! {about_key}"
"Remember: {big_msg}!"
.format(term=term,
session=session,
ssh_port=ssh_port,
about_key=about_key,
big_msg=big_msg)
)
echo(u'\r\n\r\n')
for txt in term.wrap(description, width=min(80, term.width)):
echo(term.move_x(max(0, (term.width // 2) - 40)))
echo(term.red(txt.rstrip() + '\r\n'))
echo(u'\r\n\r\n')
echo(term.center(term.bold_black('Press any key to continue: ')).rstrip())
term.inkey()
def main():
"""
x84 main entry point. The system begins and ends here.
Command line arguments to engine.py:
- ``--config=`` location of alternate configuration file
- ``--logger=`` location of alternate logging.ini file
"""
import x84.bbs.ini
# load existing .ini files or create default ones.
x84.bbs.ini.init(*parse_args())
from x84.bbs import get_ini
from x84.bbs.ini import CFG
if sys.maxunicode == 65535:
# apple is the only known bastardized variant that does this;
# presumably for memory/speed savings (UCS-2 strings are faster
# than UCS-4). Python 3 dynamically allocates string types by
# their widest content, so such things aren't necessary ...
import warnings
warnings.warn('This python is built without wide unicode support. '
'some internationalized languages will not be possible.')
# retrieve list of managed servers
servers = get_servers(CFG)
# begin unmanaged servers
if (CFG.has_section('web') and
(not CFG.has_option('web', 'enabled')
or CFG.getboolean('web', 'enabled'))):
# start https server for one or more web modules.
from x84 import webserve
webserve.main()
if get_ini(section='msg', key='network_tags'):
# start background timer to poll for new messages
# of message networks we may be a member of.
from x84 import msgpoll
msgpoll.main()
try:
# begin main event loop
_loop(servers)
except KeyboardInterrupt:
# exit on ^C, killing any client sessions.
from x84.terminal import kill_session
for server in servers:
for idx, thread in enumerate(server.threads[:]):
if not thread.stopped:
thread.stopped = True
server.threads.remove(thread)
for key, client in server.clients.items()[:]:
kill_session(client, 'server shutdown')
del server.clients[key]
return 0
def main():
"""
x84 main entry point. The system begins and ends here.
Command line arguments to engine.py:
- ``--config=`` location of alternate configuration file
- ``--logger=`` location of alternate logging.ini file
"""
# load existing .ini files or create default ones.
import x84.bbs.ini
x84.bbs.ini.init(*cmdline.parse_args())
from x84.bbs import get_ini
from x84.bbs.ini import CFG
if sys.maxunicode == 65535:
# apple is the only known bastardized variant that does this;
# presumably for memory/speed savings (UCS-2 strings are faster
# than UCS-4). Python 3 dynamically allocates string types by
# their widest content, so such things aren't necessary, there.
import warnings
warnings.warn('This python is built without wide unicode support. '
'some internationalized languages will not be possible.')
# retrieve list of managed servers
servers = get_servers(CFG)
# begin unmanaged servers
if (CFG.has_section('web') and
(not CFG.has_option('web', 'enabled')
or CFG.getboolean('web', 'enabled'))):
# start https server for one or more web modules.
from x84 import webserve
webserve.main()
if get_ini(section='msg', key='network_tags'):
# start background timer to poll for new messages
# of message networks we may be a member of.
from x84 import msgpoll
msgpoll.main()
try:
# begin main event loop
_loop(servers)
except KeyboardInterrupt:
# exit on ^C, killing any client sessions.
for server in servers:
for thread in server.threads[:]:
if not thread.stopped:
thread.stopped = True
server.threads.remove(thread)
for key, client in server.clients.items()[:]:
kill_session(client, 'server shutdown')
del server.clients[key]
return 0
def _loop(servers):
"""
Main event loop. Never returns.
"""
# pylint: disable=R0912,R0914,R0915
# Too many local variables (24/15)
import logging
import select
import sys
from x84.terminal import get_terminals, kill_session
from x84.bbs.ini import CFG
from x84.fail2ban import get_fail2ban_function
SELECT_POLL = 0.02 # polling time is 20ms
# WIN32 has no session_fds (multiprocess queues are not polled using
# select), use a persistently empty set; for WIN32, sessions are always
# polled for data at every loop.
WIN32 = sys.platform.lower().startswith('win32')
session_fds = set()
log = logging.getLogger('x84.engine')
if not len(servers):
raise ValueError("No servers configured for event loop! (ssh, telnet)")
tap_events = CFG.getboolean('session', 'tap_events')
check_ban = get_fail2ban_function()
locks = dict()
while True:
# shutdown, close & delete inactive clients,
for server in servers:
# bbs sessions that are no longer active on the socket
# level -- send them a 'kill signal'
for key, client in server.clients.items()[:]:
if not client.is_active():
kill_session(client, 'socket shutdown')
del server.clients[key]
# on-connect negotiations that have completed or failed.
# delete their thread instance from further evaluation
for thread in [_thread for _thread in server.threads
if _thread.stopped][:]:
server.threads.remove(thread)
server_fds = [server.server_socket.fileno() for server in servers]
client_fds = [fd for fd in server.client_fds() for server in servers]
check_r = server_fds + client_fds
if not WIN32:
session_fds = get_session_output_fds(servers)
check_r += session_fds
# We'd like to use timeout 'None', but the registration of
# a new client in terminal.start_process surprises us with new
# file descriptors for the session i/o. unless we loop for
# additional `session_fds', a connecting client would block.
ready_r, _, _ = select.select(check_r, [], [], SELECT_POLL)
for fd in ready_r:
# see if any new tcp connections were made
server = find_server(servers, fd)
if server is not None:
accept(log, server, check_ban)
# receive new data from tcp clients.
client_recv(servers, log)
terms = get_terminals()
# receive new data from session terminals
if WIN32 or set(session_fds) & set(ready_r):
try:
session_recv(locks, terms, log, tap_events)
except IOError, err:
# if the ipc closes while we poll, warn and continue
log.warn(err)
# send tcp data to clients
client_send(terms, log)
# send session data, poll for user-timeout and disconnect them
session_send(terms)
