def on_rx(self, message):
with self._lock:
log.debug("on_rx: %s" % message)
session_id = message['session_id']
fqdn = message['fqdn']
log.info("AgentRpcMessenger.on_rx: %s/%s" % (fqdn, session_id))
if message['type'] == 'SESSION_CREATE':
if fqdn in self._sessions:
old_session_id = self._sessions[fqdn]
self._abort_session(fqdn, "new session created", old_session_id, session_id)
else:
self._sessions[fqdn] = session_id
elif message['type'] == 'SESSION_TERMINATE':
# An agent has timed out or restarted, we're being told its session is now dead
if message['fqdn'] in self._sessions:
self._abort_session(fqdn, "session terminated", message['session_id'])
elif message['type'] == 'SESSION_TERMINATE_ALL':
# The http_agent service has restarted, all sessions are now over
for fqdn, session in self._sessions.items():
self._abort_session(fqdn, "all sessions terminated", session)
else:
rpc_response = message['body']
if rpc_response['type'] != 'ACTION_COMPLETE':
log.error("Unexpected type '%s'" % rpc_response['type'])
return
if fqdn in self._sessions and self._sessions[fqdn] != session_id:
log.info("AgentRpcMessenger.on_rx: cancelling session %s/%s (replaced by %s)" % (fqdn, self._sessions[fqdn], session_id))
self._abort_session(fqdn, "session cancelled", self._sessions[fqdn])
HttpAgentRpc().reset_session(fqdn, AgentRpcMessenger.PLUGIN_NAME, session_id)
elif fqdn in self._sessions:
log.info("AgentRpcMessenger.on_rx: good session %s/%s" % (fqdn, session_id))
# Find this RPC and complete it
try:
rpc = self._session_rpcs[session_id][rpc_response['id']]
except KeyError:
if rpc_response['id'] in self._cancelled_rpcs:
log.debug("Response received from a cancelled RPC (id: %s)", rpc_response['id'])
else:
log.error("Response received from UNKNOWN RPC of (id: %s)", rpc_response['id'])
else:
del self._session_rpcs[session_id][rpc_response['id']]
rpc.exception = rpc_response['exception']
rpc.result = rpc_response['result']
rpc.subprocesses = rpc_response['subprocesses']
log.info("AgentRpcMessenger.on_rx: completing rpc %s" % rpc.id)
rpc.complete.set()
else:
log.info("AgentRpcMessenger.on_rx: unknown session %s/%s" % (fqdn, session_id))
# A session I never heard of?
HttpAgentRpc().reset_session(fqdn, AgentRpcMessenger.PLUGIN_NAME, session_id)
def run(self):
try:
HttpAgentRpc().reset_plugin_sessions(AgentRpcMessenger.PLUGIN_NAME)
except RpcTimeout:
# Assume this means that the http_agent service isn't running: this
# is acceptable, as our goal of there not being any sessions is
# already the case.
log.warning("Unable to reset %s sessions" % AgentRpcMessenger.PLUGIN_NAME)
self._action_runner_rx_queue.serve(session_callback = self.on_rx)
log.info("AgentRpcMessenger.complete")
def test_revoked_cert(self):
"""Check that I'm bounced if my certificate is revoked"""
# Initially should be able to to operations like open a session
self._open_session()
HttpAgentRpc().remove_host(self.host.fqdn)
# After revokation any access should be bounced
response = self._post([])
self.assertEqual(response.status_code, 403)
response = self._get()
self.assertEqual(response.status_code, 403)
def on_message(self, message):
with self._processing_lock:
fqdn = message["fqdn"]
assert message["plugin"] == self._plugin_name
if message["type"] != "DATA":
# We are session aware in that we check sequence numbers etc, but
# we don't actually require any actions on SESSION_CREATE or
# SESSION_TERMINATE.
assert message["type"] in ("SESSION_CREATE",
"SESSION_TERMINATE")
return
try:
host = ManagedHost.objects.get(fqdn=fqdn)
except ManagedHost.DoesNotExist:
log.error("Received agent message for non-existent host %s" %
fqdn)
return
log.debug("Received agent message for %s/%s/%s" %
(fqdn, message["plugin"], message["session_id"]))
existing_session = self._sessions.get(host.id, None)
if existing_session is None:
if message["session_seq"] == 0:
# No existing session, start a new one
log.info("New session")
self._sessions[host.id] = Session(
message["session_id"],
self._create_plugin_instance(host))
else:
# Partway through a session, reset it
log.info(
"Nonzero counter for new (to me) session, resetting")
HttpAgentRpc().reset_session(fqdn, self._plugin_name,
message["session_id"])
return
elif existing_session.id != message["session_id"]:
if message["session_seq"] == 0:
# Existing session to be replaced with this one
log.info("Replacing session %s/%s with %s/%s" %
(self._plugin_name, existing_session.id,
self._plugin_name, message["session_id"]))
self._sessions[host.id] = Session(
message["session_id"],
self._create_plugin_instance(host))
else:
# Existing session is dead, new session is not at zero, must send a reset
log.info(
"Nonzero counter for new (to me) replacement session, resetting"
)
del self._sessions[host.id]
HttpAgentRpc().reset_session(fqdn, self._plugin_name,
message["session_id"])
return
else:
if message["session_seq"] == existing_session.seq + 1:
# Continuation of session
pass
else:
# Got out of sequence, reset it
log.info(
"Out of sequence message (seq %s, expected %s), resetting"
% (message["session_seq"], existing_session.seq + 1))
del self._sessions[host.id]
HttpAgentRpc().reset_session(fqdn, self._plugin_name,
message["session_id"])
return
session = self._sessions.get(host.id, None)
try:
if message["session_seq"] == 0:
session.plugin.do_agent_session_start(message["body"])
else:
session.seq += 1
session.plugin.do_agent_session_continue(message["body"])
except Exception:
exc_info = sys.exc_info()
backtrace = "\n".join(
traceback.format_exception(*(exc_info or sys.exc_info())))
log.error("Exception in agent session for %s from %s: %s" %
(self._plugin_name, host, backtrace))
log.error("Data: %s" % message["body"])
HttpAgentRpc().reset_session(fqdn, self._plugin_name,
message["session_id"])