paradoxxxzero_butterfly/butterfly/terminal.py
Florian Mounier fbd71d55ef Fix lint
2018-06-04 11:03:06 +02:00

361 lines
12 KiB
Python

# *-* coding: utf-8 *-*
# This file is part of butterfly
#
# butterfly Copyright(C) 2015-2017 Florian Mounier
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import fcntl
import io
import os
import pty
import random
import signal
import string
import struct
import sys
import termios
from logging import getLogger
import tornado.ioloop
import tornado.options
import tornado.process
import tornado.web
import tornado.websocket
from butterfly import __version__, utils
log = getLogger('butterfly')
ioloop = tornado.ioloop.IOLoop.instance()
server = utils.User()
daemon = utils.User(name='daemon')
# Python 2 backward compatibility
try:
input = raw_input
except NameError:
pass
class Terminal(object):
sessions = {}
def __init__(self, user, path, session, socket, uri, render_string,
broadcast):
self.sessions[session] = self
self.history_size = 50000
self.history = ''
self.uri = uri
self.session = session
self.broadcast = broadcast
self.fd = None
self.closed = False
self.socket = socket
log.info('Terminal opening with session: %s and socket %r' % (
self.session, self.socket))
self.path = path
self.user = user if user else None
self.caller = self.callee = None
# If local we have the user connecting
if self.socket.local and self.socket.user is not None:
self.caller = self.socket.user
if tornado.options.options.unsecure:
if self.user:
try:
self.callee = self.user
except LookupError:
log.debug(
"Can't switch to user %s" % self.user, exc_info=True)
self.callee = None
# If no user where given and we are local, keep the same
# user as the one who opened the socket ie: the one
# openning a terminal in browser
if not self.callee and not self.user and self.socket.local:
self.user = self.callee = self.caller
else:
# Authed user
self.callee = self.user
if tornado.options.options.motd != '':
motd = (render_string(
tornado.options.options.motd,
butterfly=self,
version=__version__,
opts=tornado.options.options,
uri=self.uri,
colors=utils.ansi_colors
).decode('utf-8')
.replace('\r', '')
.replace('\n', '\r\n'))
self.send(motd)
log.info('Forking pty for user %r' % self.user)
def send(self, message):
if message is not None:
self.history += message
if len(self.history) > self.history_size:
self.history = self.history[-self.history_size:]
self.broadcast(self.session, message)
def pty(self):
# Make a "unique" id in 4 bytes
self.uid = ''.join(
random.choice(
string.ascii_lowercase + string.ascii_uppercase +
string.digits)
for _ in range(4))
self.pid, self.fd = pty.fork()
if self.pid == 0:
self.determine_user()
log.debug('Pty forked for user %r caller %r callee %r' % (
self.user, self.caller, self.callee))
self.shell()
else:
self.communicate()
def determine_user(self):
if not tornado.options.options.unsecure:
# Secure mode we must have already a callee
assert self.callee is not None
return
# If we should login, login
if tornado.options.options.login:
user = ''
while user == '':
try:
user = input('login: ')
except (KeyboardInterrupt, EOFError):
log.debug("Error in login input", exc_info=True)
pass
try:
self.callee = utils.User(name=user)
except Exception:
log.debug("Can't switch to user %s" % user, exc_info=True)
self.callee = utils.User(name='nobody')
return
# if login is not required, we will use the same user as
# butterfly is executed
self.callee = self.callee or utils.User()
def shell(self):
try:
os.chdir(self.path or self.callee.dir)
except Exception:
log.debug(
"Can't chdir to %s" % (self.path or self.callee.dir),
exc_info=True)
# If local and local user is the same as login user
# We set the env of the user from the browser
# Usefull when running as root
if self.caller == self.callee:
env = os.environ
env.update(self.socket.env)
else:
# May need more?
env = {}
env["TERM"] = "xterm-256color"
env["COLORTERM"] = "butterfly"
env["HOME"] = self.callee.dir
env["LOCATION"] = self.uri
env['BUTTERFLY_PATH'] = os.path.abspath(os.path.join(
os.path.dirname(__file__), 'bin'))
try:
tty = os.ttyname(0).replace('/dev/', '')
except Exception:
log.debug("Can't get ttyname", exc_info=True)
tty = ''
if self.caller != self.callee:
try:
os.chown(os.ttyname(0), self.callee.uid, -1)
except Exception:
log.debug("Can't chown ttyname", exc_info=True)
utils.add_user_info(
self.uid,
tty, os.getpid(),
self.callee.name, self.uri)
local_login = (
self.socket.local and self.caller == self.callee and
server == self.callee)
secure = not tornado.options.options.unsecure
force_login = tornado.options.options.login
ignore_security = (
tornado.options.options.
i_hereby_declare_i_dont_want_any_security_whatsoever)
if not force_login and (ignore_security or secure or local_login):
# User has been auth with ssl or is the same user as server
# or login is explicitly turned off
if secure and not local_login:
# User is authed by ssl, setting groups
try:
os.initgroups(self.callee.name, self.callee.gid)
os.setgid(self.callee.gid)
os.setuid(self.callee.uid)
# Apparently necessary for some cmd
env['LOGNAME'] = env['USER'] = self.callee.name
except Exception:
log.error(
'The server must be run as root '
'if you want to log as different user\n',
exc_info=True)
sys.exit(1)
if tornado.options.options.cmd:
args = tornado.options.options.cmd.split(' ')
else:
args = [tornado.options.options.shell or self.callee.shell]
args.append('-il')
# In some cases some shells don't export SHELL var
env['SHELL'] = args[0]
os.execvpe(args[0], args, env)
# This process has been replaced
if tornado.options.options.pam_profile:
if not server.root:
print('You must be root to use pam_profile option.')
sys.exit(3)
pam_path = os.path.join(
os.path.dirname(os.path.realpath(__file__)), 'pam.py')
os.execvpe(sys.executable, [
sys.executable, pam_path, self.callee.name,
tornado.options.options.pam_profile], env)
# Unsecure connection with su
if server.root:
if self.socket.local:
if self.callee != self.caller:
# Force password prompt by dropping rights
# to the daemon user
os.setuid(daemon.uid)
else:
# We are not local so we should always get a password prompt
if self.callee == daemon:
# No logging from daemon
sys.exit(1)
os.setuid(daemon.uid)
if os.path.exists('/usr/bin/su'):
args = ['/usr/bin/su']
else:
args = ['/bin/su']
args.append('-l')
if sys.platform.startswith('linux') and tornado.options.options.shell:
args.append('-s')
args.append(tornado.options.options.shell)
args.append(self.callee.name)
os.execvpe(args[0], args, env)
def communicate(self):
fcntl.fcntl(self.fd, fcntl.F_SETFL, os.O_NONBLOCK)
def utf8_error(e):
log.error(e)
self.reader = io.open(
self.fd,
'rb',
buffering=0,
closefd=False
)
self.writer = io.open(
self.fd,
'wt',
encoding='utf-8',
closefd=False
)
ioloop.add_handler(
self.fd, self.shell_handler, ioloop.READ | ioloop.ERROR)
def write(self, message):
if not hasattr(self, 'writer'):
self.on_close()
self.close()
log.debug('WRIT<%r' % message)
self.writer.write(message)
self.writer.flush()
def ctl(self, message):
if message['cmd'] == 'size':
cols = message['cols']
rows = message['rows']
s = struct.pack("HHHH", rows, cols, 0, 0)
fcntl.ioctl(self.fd, termios.TIOCSWINSZ, s)
log.info('SIZE (%d, %d)' % (cols, rows))
def shell_handler(self, fd, events):
if events & ioloop.READ:
try:
read = self.reader.read()
except IOError:
read = ''
log.debug('READ>%r' % read)
if read and len(read) != 0:
self.send(read.decode('utf-8', 'replace'))
else:
events = ioloop.ERROR
if events & ioloop.ERROR:
log.info('Error on fd %d, closing' % fd)
# Terminated
self.send(None) # Close all
self.close()
def close(self):
if self.closed:
return
self.closed = True
if self.fd is not None:
log.info('Closing fd %d' % self.fd)
if getattr(self, 'pid', 0) == 0:
log.info('pid is 0')
return
utils.rm_user_info(self.uid, self.pid)
try:
ioloop.remove_handler(self.fd)
except Exception:
log.error('handler removal fail', exc_info=True)
try:
os.close(self.fd)
except Exception:
log.debug('closing fd fail', exc_info=True)
try:
os.kill(self.pid, signal.SIGHUP)
os.kill(self.pid, signal.SIGCONT)
os.waitpid(self.pid, 0)
except Exception:
log.debug('waitpid fail', exc_info=True)
del self.sessions[self.session]