commit fa9314123b702feee230f7974bfbad2d783d8365 Author: juga0 juga@riseup.net Date: Tue Feb 2 11:56:05 2021 +0000

fix: scanner: extract method to create paths

because `measure_relay` method is too long, confusing and we have had several bugs in this part of the code. --- sbws/core/scanner.py | 42 ++++++++++++++++++++++++++---------------- 1 file changed, 26 insertions(+), 16 deletions(-)

diff --git a/sbws/core/scanner.py b/sbws/core/scanner.py index 2736059..228ad74 100644 --- a/sbws/core/scanner.py +++ b/sbws/core/scanner.py @@ -244,6 +244,27 @@ def _pick_ideal_second_hop(relay, dest, rl, cont, is_exit): return chosen

+def create_path_relay_as_entry(relay, dest, rl, cb): + circ_fps = nicknames = [] + helper = _pick_ideal_second_hop( + relay, dest, rl, cb.controller, is_exit=True) + if helper: + circ_fps = [relay.fingerprint, helper.fingerprint] + nicknames = [relay.nickname, helper.nickname] + return helper, circ_fps, nicknames + + +def create_path_relay_as_exit(relay, dest, rl, cb): + circ_fps = nicknames = [] + helper = _pick_ideal_second_hop( + relay, dest, rl, cb.controller, is_exit=False) + if helper: + circ_fps = [helper.fingerprint, relay.fingerprint] + # stored for debugging + nicknames = [helper.nickname, relay.nickname] + return helper, circ_fps, nicknames + + def measure_relay(args, conf, destinations, cb, rl, relay): """ Select a Web server, a relay to build the circuit, @@ -295,18 +316,11 @@ def measure_relay(args, conf, destinations, cb, rl, relay): helper = None circ_fps = None if relay.is_exit_not_bad_allowing_port_all_ips(dest.port): - helper = _pick_ideal_second_hop( - relay, dest, rl, cb.controller, is_exit=False) - if helper: - circ_fps = [helper.fingerprint, relay.fingerprint] - # stored for debugging - nicknames = [helper.nickname, relay.nickname] + helper, circ_fps, nicknames = create_path_relay_as_exit( + relay, dest, rl, cb) else: - helper = _pick_ideal_second_hop( - relay, dest, rl, cb.controller, is_exit=True) - if helper: - circ_fps = [relay.fingerprint, helper.fingerprint] - nicknames = [relay.nickname, helper.nickname] + helper, circ_fps, nicknames = create_path_relay_as_entry( + relay, dest, rl, cb) if not helper: reason = 'Unable to select a second relay' log.debug(reason + ' to help measure %s (%s)', @@ -323,11 +337,7 @@ def measure_relay(args, conf, destinations, cb, rl, relay): # If that's the case, try again using them as 2nd hop. # We could reuse the helper, but it does not need to be an exit now, # so choose other again. - helper = _pick_ideal_second_hop( - relay, dest, rl, cb.controller, is_exit=False) - if helper: - circ_fps = [helper.fingerprint, relay.fingerprint] - nicknames = [helper.nickname, relay.nickname] + create_path_relay_as_exit(relay, dest, rl, cb) circ_id, reason = cb.build_circuit(circ_fps) if not circ_id: log.debug('Could not build circuit with path %s (%s): %s ',