[tor-bugs] #11069 [Tor]: Tor with unreachable PTs should not hang the bootstrap process

[Tor Bug Tracker & Wiki]

#11069: Tor with unreachable PTs should not hang the bootstrap process
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     Reporter:  asn     |      Owner:
         Type:  defect  |     Status:  new
     Priority:  normal  |  Milestone:  Tor: 0.2.5.x-final
    Component:  Tor     |    Version:
   Resolution:          |   Keywords:  tor-pt tor-client
Actual Points:          |  Parent ID:
       Points:          |
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Comment (by asn):

 OK, I did some digging and found out that if you start Tor with bridges,
 Tor will start OR connections for each bridge. It does so because of
 `fetch_bridge_descriptors()` -> `launch_direct_bridge_descriptor_fetch()`
 -> ... -> `circuit_launch_by_extend_info()`.

 In this light, checking if 'we are using bridges && no bridge descriptors
 && we are the last OR connection' in `control_event_bootstrap_problem()`
 kind of makes sense as a fix. Maybe we should make a function called
 `we_are_last_or_conn(const or_connection_t *conn)` that cycles through the
 connection list, and sees if there are any active OR conns apart from
 `conn`? Then use that function instead of
 `any_pending_bridge_descriptor_fetches()`?

 Otherwise, we could mark the current connection as closed before stepping
 into `control_event_bootstrap_problem()` and then checking if there are
 any active OR connections left.

 Also, is there anything that would create extra OR connections during
 bootstrap apart from bridges? We should make sure that there is not,
 because with the current proposed fix we would consider those connection
 as connections to bridges and not raise the warning.

 Nick?

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/11069#comment:9>
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