Refactor code, increase security

master
root 2022-12-05 18:45:58 +00:00
parent 51304e3426
commit d5a2326d2a
3 changed files with 61 additions and 63 deletions

View File

@ -12,11 +12,10 @@ def create_instance(container_name: str, instance_password: str):
instance = lxd_client.instances.create(config, wait=True) instance = lxd_client.instances.create(config, wait=True)
instance.start(wait=True) instance.start(wait=True)
setup_ssh(container_name, instance_password)
while type(ipaddress.ip_address(instance.state().network['eth0']['addresses'][0]['address'])) != ipaddress.IPv4Address: while type(ipaddress.ip_address(instance.state().network['eth0']['addresses'][0]['address'])) != ipaddress.IPv4Address:
time.sleep(0.1) time.sleep(0.1)
setup_ssh(container_name, instance_password)
return instance.state().network['eth0']['addresses'][0] return instance.state().network['eth0']['addresses'][0]
@ -58,6 +57,10 @@ def setup_ssh(container_name: str, instance_password: str):
def get_networking(container_name: str): def get_networking(container_name: str):
instance = lxd_client.instances.get(container_name) instance = lxd_client.instances.get(container_name)
while instance.state().network is None or \
type(ipaddress.ip_address(instance.state().network['eth0']['addresses'][0]['address'])) != ipaddress.IPv4Address:
time.sleep(0.1)
return instance.state().network['eth0']['addresses'][0] return instance.state().network['eth0']['addresses'][0]

View File

@ -15,7 +15,8 @@ def connect_handler(script: sshim.Script):
pass pass
server = sshim.Server(connect_handler, address='127.0.0.1', port=3022) server = sshim.Server(connect_handler, address='0.0.0.0'
'', port=3022)
try: try:
server.run() server.run()
except KeyboardInterrupt: except KeyboardInterrupt:

View File

@ -8,6 +8,8 @@ import threading
import logging import logging
import select import select
import time import time
import ipaddress
import secrets
import inspect import inspect
logger = logging.getLogger(__name__) logger = logging.getLogger(__name__)
@ -22,37 +24,38 @@ def check_channel_request(self, kind, channel_id):
def check_channel_shell_request(self, channel): def check_channel_shell_request(self, channel):
logger.debug("Check channel shell request: %s" % channel.get_id()) logger.debug("Check channel shell request: %s" % channel.get_id())
self.runner.set_shell_channel(channel) Runner(self, self.username, 'shell', channel).start()
return True return True
def check_channel_exec_request(self, channel): def check_channel_exec_request(self, channel):
logger.debug("Check channel exec request: %s" % channel.get_id()) logger.debug("Check channel exec request: %s" % channel.get_id())
self.runner.set_shell_channel(channel) Runner(self, self.username, 'exec', channel).start()
return True return True
def check_channel_subsystem_request(self, channel, name): def check_channel_subsystem_request(self, channel, name):
if name == 'sftp': if name == 'sftp':
self.runner.set_sftp_channel(channel) Runner(self, self.username, 'sftp', channel).start()
return True return True
else: else:
return False return False
def check_auth_none(self, username): def check_auth_none(self, username):
if username == os.environ["SSH_USERNAME"]:
return paramiko.AUTH_PARTIALLY_SUCCESSFUL
return paramiko.AUTH_FAILED return paramiko.AUTH_FAILED
def check_auth_password(self, username, password): def check_auth_password(self, username, password):
logger.debug(f"{username} just tried to connect") logger.debug(f"{username} just tried to connect")
if username == os.environ["SSH_USERNAME"] and password == os.environ["SSH_PASSWORD"]: # ensure that the connection is made from a local ip
self.runner = Runner(self, os.environ["SSH_USERNAME"], self.transport) if ipaddress.ip_address(self.address).is_private is not True:
self.runner.start() return paramiko.AUTH_FAILED
if secrets.compare_digest(password, os.environ["SSH_PASSWORD"]):
self.username = username
Runner(self, self.username).start()
return paramiko.AUTH_SUCCESSFUL return paramiko.AUTH_SUCCESSFUL
return paramiko.AUTH_FAILED return paramiko.AUTH_FAILED
@ -62,17 +65,15 @@ def check_auth_publickey(self, username, key):
class Runner(threading.Thread): class Runner(threading.Thread):
def __init__(self, client, username: str, transport: paramiko.Transport, start_instance: bool = True): def __init__(self, client, username: str, channel_type: str = None, channel: paramiko.Channel = None):
self.instance_name = "instance-" + username self.instance_name = "instance-" + username
self.runner_identifier = "runner-" + str(uuid.uuid4()) self.runner_identifier = "runner-" + str(uuid.uuid4())
threading.Thread.__init__(self, name=f'sshim.Runner {self.instance_name} {self.runner_identifier}') threading.Thread.__init__(self, name=f'sshim.Runner {self.instance_name} {self.runner_identifier}')
self.instance_password = self.instance_name # TODO: fix - VERY INSECURE! self.instance_password = self.instance_name # TODO: fix - VERY INSECURE!
self.daemon = True self.daemon = True
self.client = client self.client = client
self.transport = transport self.channel_type = channel_type
self.start_instance = start_instance self.channel = channel
self.shell_channel = None
self.sftp_channel = None
def run(self) -> None: def run(self) -> None:
try: try:
@ -81,56 +82,38 @@ class Runner(threading.Thread):
logger.debug(e) logger.debug(e)
vm_ip = lxd_interface.get_networking(self.instance_name)['address'] vm_ip = lxd_interface.get_networking(self.instance_name)['address']
if self.channel is None:
return None
with paramiko.SSHClient() as ssh_client: with paramiko.SSHClient() as ssh_client:
ssh_client.set_missing_host_key_policy(paramiko.WarningPolicy) ssh_client.set_missing_host_key_policy(paramiko.WarningPolicy)
try_limit = 10 # TODO: load from config
tries = 0
while tries <= try_limit:
try:
ssh_client.connect(vm_ip, username='root', password=self.instance_password) ssh_client.connect(vm_ip, username='root', password=self.instance_password)
client_shell_channel = ssh_client.invoke_shell() break
client_sftp_channel = ssh_client.open_sftp().get_channel() except Exception as e: # TODO: narrow exception
if tries >= try_limit:
raise
logger.debug(e)
tries += 1
time.sleep(0.2)
if self.channel_type == "shell" or self.channel_type == "exec":
client_channel = ssh_client.invoke_shell()
elif self.channel_type == "sftp":
client_channel = ssh_client.open_sftp().get_channel()
last_save_time = round(time.time()) last_save_time = round(time.time())
lxd_interface.set_description(self.instance_name, str(last_save_time)) lxd_interface.set_description(self.instance_name, str(last_save_time))
while True: forward_channel_return = True
while forward_channel_return is True:
current_time_rounded = round(time.time()) current_time_rounded = round(time.time())
if current_time_rounded != last_save_time: if current_time_rounded != last_save_time:
lxd_interface.set_description(self.instance_name, str(current_time_rounded)) lxd_interface.set_description(self.instance_name, str(current_time_rounded))
last_save_time = current_time_rounded last_save_time = current_time_rounded
if self.shell_channel is not None: forward_channel_return = self.forward_channel(client_channel)
r, w, e = select.select([client_shell_channel, self.shell_channel], [], [])
if self.shell_channel in r:
x = self.shell_channel.recv(1024)
if len(x) == 0:
self.shell_channel.close()
self.shell_channel = None
break
client_shell_channel.send(x)
if client_shell_channel in r:
x = client_shell_channel.recv(1024)
if len(x) == 0:
self.shell_channel.close()
self.shell_channel = None
break
self.shell_channel.send(x)
if self.sftp_channel is not None: # TODO: move this to function
r, w, e = select.select([client_sftp_channel, self.sftp_channel], [], [])
if self.sftp_channel in r:
x = self.sftp_channel.recv(1024)
if len(x) == 0:
self.sftp_channel.close()
self.sftp_channel = None
break
client_sftp_channel.send(x)
if client_sftp_channel in r:
x = client_sftp_channel.recv(1024)
if len(x) == 0:
self.sftp_channel.close()
self.sftp_channel = None
break
self.sftp_channel.send(x)
if self.transport.is_active() is False:
break
exit_time = round(time.time()) exit_time = round(time.time())
time.sleep(10) time.sleep(10)
@ -143,13 +126,24 @@ class Runner(threading.Thread):
lxd_interface.destroy_instance(self.instance_name) lxd_interface.destroy_instance(self.instance_name)
break break
def set_shell_channel(self, channel): def forward_channel(self, client_channel) -> bool:
self.shell_channel = channel if self.channel is None:
self.shell_channel.settimeout(None) return False
else:
def set_sftp_channel(self, channel): r, w, e = select.select([client_channel, self.channel], [], [])
self.sftp_channel = channel if self.channel in r:
self.sftp_channel.settimeout(None) x = self.channel.recv(1024)
if len(x) == 0:
self.channel.close()
return False
client_channel.send(x)
if client_channel in r:
x = client_channel.recv(1024)
if len(x) == 0:
self.channel.close()
return False
self.channel.send(x)
return True
Handler.check_channel_request = check_channel_request Handler.check_channel_request = check_channel_request