diff options
| -rw-r--r-- | mpm/python/usrp_mpm/rpc_server.py | 39 |
1 files changed, 31 insertions, 8 deletions
diff --git a/mpm/python/usrp_mpm/rpc_server.py b/mpm/python/usrp_mpm/rpc_server.py index 0084184f1..4fbaa248f 100644 --- a/mpm/python/usrp_mpm/rpc_server.py +++ b/mpm/python/usrp_mpm/rpc_server.py @@ -34,6 +34,7 @@ from builtins import range from mprpc import RPCServer from .mpmlog import get_main_logger +TIMEOUT_INTERVAL = 3.0 # Seconds before claim expires TOKEN_LEN = 16 # Length of the token string def no_claim(func): @@ -60,6 +61,7 @@ class MPMServer(RPCServer): self.log = get_main_logger().getChild('RPCServer') self._state = state self._timer = Greenlet() + self.session_id = None self.periph_manager = mgr # add public mboard methods without namespace self._update_component_commands(mgr, '', '_mb_methods') @@ -68,6 +70,17 @@ class MPMServer(RPCServer): self._update_component_commands(dboard, 'db_' + str(db_slot) + '_', '_db_methods') super(MPMServer, self).__init__(*args, **kwargs) + def _check_token_valid(self, token): + """ + Returns True iff: + - The device is currently claimed + - The claim token matches the one passed in + """ + return self._state.claim_status.value and \ + len(token) == TOKEN_LEN and \ + self._state.claim_token.value == bytes(token, 'ascii') + + def _update_component_commands(self, component, namespace, storage): """ Detect available methods for an object and add them to the RPC server. @@ -101,9 +114,9 @@ class MPMServer(RPCServer): self.log.trace("adding command %s pointing to %s", command, function) def new_claimed_function(token, *args): " Define a function that requires a claim token check " - if bytes(token[:TOKEN_LEN], 'ascii') != self._state.claim_token.value: + if not self._check_token_valid(token): self.log.warning( - "Stopped attempt to access function `{}' with invalid " \ + "Thwarted attempt to access function `{}' with invalid " \ "token `{}'.".format(command, token) ) raise RuntimeError("Invalid token!") @@ -168,7 +181,7 @@ class MPMServer(RPCServer): """ self._state.lock.acquire() if self._state.claim_status.value: - if self._state.claim_token.value == bytes(token[:TOKEN_LEN], 'ascii'): + if self._check_token_valid(token): self._state.lock.release() self.log.debug("reclaimed from: %s", self.client_host) self._reset_timer() @@ -179,14 +192,19 @@ class MPMServer(RPCServer): self.client_host, token[:TOKEN_LEN] ) return False - self.log.debug("trying to reclaim unclaimed device from: %s", self.client_host) + self.log.debug( + "trying to reclaim unclaimed device from: %s", + self.client_host + ) return False def _unclaim(self): """ unconditional unclaim - for internal use """ - self.log.debug("releasing claim") + self.log.debug("Releasing claim on session `{}' by `{}'".format( + self.session_id, self.client_host + )) self._state.claim_status.value = False self._state.claim_token.value = b'' self.session_id = None @@ -199,15 +217,17 @@ class MPMServer(RPCServer): reset unclaim timer """ self._timer.kill() - self._timer = spawn_later(2.0, self._unclaim) + self._timer = spawn_later(TIMEOUT_INTERVAL, self._unclaim) def unclaim(self, token): """ - unclaim `token` - unclaims the MPM device if it is claimed with this token + unclaim `token` - unclaims the MPM device if it is claimed with this + token """ - if self._state.claim_status.value and self._state.claim_token.value == token: + if self._check_token_valid(token): self._unclaim() return True + self.log.warning("Attempt to unclaim session with invalid token!") return False def get_device_info(self): @@ -227,6 +247,9 @@ class MPMServer(RPCServer): Forwards the call to periph_manager._allocate_sid with the client ip addresss as argument. Should be used to setup interfaces """ + if not self._check_token_valid(token): + self.log.warning("Attempt to allocate SID without valid token!") + return None return self.periph_manager._allocate_sid(self.client_host, *args) |