commit 88fae60bc7b420ca7f36f92b482401b8a7adebaf Author: Matt Traudt sirmatt@ksu.edu Date: Wed Jun 6 20:43:42 2018 -0400

Fix assertion if stem can't find a relay

2018-06-06 04:42:03 ERROR Thread-5 scanner.py:225 - dispatch_worker_thread - Unhandled exception in worker thread Traceback (most recent call last): File "/home/pastly/src/simple-bw-scanner/sbws/core/scanner.py", line 223, in dispatch_worker_thread return measure_relay(*a, **kw) File "/home/pastly/src/simple-bw-scanner/sbws/core/scanner.py", line 138, in measure_relay dest = destinations.next() File "/home/pastly/src/simple-bw-scanner/sbws/lib/destination.py", line 222, in next self._perform_usability_test() File "/home/pastly/src/simple-bw-scanner/sbws/lib/destination.py", line 171, in _perform_usability_test circ_id = self._cb.build_circuit([None, exit.fingerprint]) File "/home/pastly/src/simple-bw-scanner/sbws/lib/circuitbuilder.py", line 175, in build_circuit for r in path] File "/home/pastly/src/simple-bw-scanner/sbws/lib/circuitbuilder.py", line 175, in <listcomp> for r in path] AttributeError: 'NoneType' object has no attribute 'fingerprint' 2018-06-06 04:42:03 ERROR Thread-10 scanner.py:280 - closure - Unhandled exception caught while measuring torbogen: <class 'AttributeError'> 'NoneType' object has no attribute 'fingerprint' --- sbws/lib/circuitbuilder.py | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/sbws/lib/circuitbuilder.py b/sbws/lib/circuitbuilder.py index d7dbe90..ac5603b 100644 --- a/sbws/lib/circuitbuilder.py +++ b/sbws/lib/circuitbuilder.py @@ -147,8 +147,20 @@ class GapsCircuitBuilder(CircuitBuilder): continue chosen_fps.append(choice) black_fps.append(choice) - return [stem_utils.fp_or_nick_to_relay(self.controller, fp) - for fp in chosen_fps] + relays = [] + for fp in chosen_fps: + relay = stem_utils.fp_or_nick_to_relay(self.controller, fp) + if not relay: + log.warning( + 'We're selecting a handful of random relays and stem ' + 'doesn't think one of the fingerprints we gave it goes ' + 'to a relay. Maybe we got a new consensus since the last ' + 'time we refreshed our list of relays. In any case, we ' + 'could try to recover. But failing inside ' + '_random_sample_relays is easier. Sorry.') + return None + relays.append(relay) + return relays

def build_circuit(self, path): ''' <path> is a list of relays and Falsey values. Relays can be