Commit Graph

23 Commits

Author SHA1 Message Date
Nick Mathewson
c1deabd3b0 Run our #else/#endif annotator on our source code. 2017-09-15 16:24:44 -04:00
teor
033691212a
Make an assert into a BUG warning in the bridge code
If future code asks if there are any running bridges, without checking
if bridges are enabled, log a BUG warning rather than crashing.

Fixes 23524 on 0.3.0.1-alpha
2017-09-15 14:02:22 +10:00
teor
d60e7df2da
Explain where bridge download statuses are initialised
And why we can't initialise them on config

Comment-only change, follow-up to 23347.
2017-09-15 13:50:29 +10:00
Nick Mathewson
63af663b8c Remove a download_status_reset() call that led to a crash -- see 23347 2017-09-14 08:47:11 -04:00
teor
1b5e34badb Add a missing bridge download status reset
17750 made unused download schedules automatically reset.
But we should make that explicit.
2017-09-12 10:38:25 -04:00
teor
93a8ed3b83 Make clients wait to refresh bridges when they have a recent descriptor
But when clients are just starting, make them try each bridge a few times
before giving up on it.

These changes make the bridge download schedules more explicit: before
17750, they relied on undocumented behaviour and specific schedule
entries. (And between 17750 and this fix, they were broken.)

Fixes 23347, not in any released version of tor.
2017-09-12 10:38:25 -04:00
teor
6370fb77c5 Refactor bridge download statuses to increment on attempt
We were always incrementing bridge download statuses on each attempt,
but we were using the "increment on failure" functions to do it.
And we never incremented them on failure.

No behaviour change.
2017-09-12 10:38:25 -04:00
teor
97249c4f5e Make bridge clients download bridge descriptors immediately
The download schedule tells Tor to wait 15 minutes before downloading
bridge descriptors. But 17750 made Tor ignore that and start immediately.
Since we fixed 17750, Tor waits 15 minutes for bridge client bootstrap,
like the schedule says.

This fixes the download schedule to start immediately, and to try each
bridge 3 times in the first 30 seconds. This should make bridge bootstraps
more reliable.

Fixes 23347.
2017-09-12 10:38:25 -04:00
George Kadianakis
52498b8183 Set guard state on bridge descriptor fetches.
We used to not set the guard state in launch_direct_bridge_descriptor_fetch().
So when a bridge descriptor fetch failed, the guard subsystem would never
learn about the fail (and hence the guard's reachability state would not
be updated).
2017-05-22 15:57:33 +03:00
Nick Mathewson
4e393f5318 Make launch_direct_bridge_descriptor_fetch use dirreqs. 2017-04-21 14:47:14 -04:00
Nick Mathewson
7505f452c8 Run the copyright update script. 2017-03-15 16:13:17 -04:00
George Kadianakis
6cab0f8ad7 Fix failing bridges+ipv6-min integration test.
The bridges+ipv6-min integration test has a client with bridges:
    Bridge 127.0.0.1:5003
    Bridge [::1]:5003
which got stuck in guard_selection_have_enough_dir_info_to_build_circuits()
because it couldn't find the descriptor of both bridges.

Specifically, the guard_has_descriptor() function could not find the
node_t of the [::1] bridge, because the [::1] bridge had no identity
digest assigned to it.

After further examination, it seems that during fetching the descriptor
for our bridges, we used the CERTS cell to fill the identity digest of
127.0.0.1:5003 properly. However, when we received a CERTS cell from
[::1]:5003 we actually ignored its identity digest because the
learned_router_identity() function was using
get_configured_bridge_by_addr_port_digest() which was returning the
127.0.0.1 bridge instead of the [::1] bridge (because it prioritizes
digest matching over addrport matching).

The fix replaces get_configured_bridge_by_addr_port_digest() with the
recent get_configured_bridge_by_exact_addr_port_digest() function. It
also relaxes the constraints of the
get_configured_bridge_by_exact_addr_port_digest() function by making it
return bridges whose identity digest is not yet known.

By using the _exact_() function, learned_router_identity() actually
fills in the identity digest of the [::1] bridge, which then allows
guard_has_descriptor() to find the right node_t and verify that the
descriptor is there.

FWIW, in the bridges+ipv6-min test both 127.0.0.1 and [::1] bridges
correspond to the same node_t, which I guess makes sense given that it's
actually the same underlying bridge.
2017-03-09 09:19:19 -05:00
Nick Mathewson
1582adabbb Change approach to preventing duplicate guards.
Previously I'd made a bad assumption in the implementation of
prop271 in 0.3.0.1-alpha: I'd assumed that there couldn't be two
guards with the same identity.  That's true for non-bridges, but in
the bridge case, we allow two bridges to have the same ID if they
have different addr:port combinations -- in order to have the same
bridge ID running multiple PTs.

Fortunately, this assumption wasn't deeply ingrained: we stop
enforcing the "one guard per ID" rule in the bridge case, and
instead enforce "one guard per <id,addr,port>".

We also needed to tweak our implementation of
get_bridge_info_for_guard, since it made the same incorrect
assumption.

Fixes bug 21027; bugfix on 0.3.0.1-alpha.
2017-02-28 08:16:33 -05:00
Nick Mathewson
a31a5581ee Remove UseDeprecatedGuardAlgorithm. 2017-01-18 15:33:26 -05:00
Nick Mathewson
472b277207 Remove the (no longer compiled) code for legacy guard selection.
Part of 20830.
2017-01-18 15:27:10 -05:00
Nick Mathewson
2cee38f76a Merge branch 'prop271_030_v1_squashed' 2016-12-16 11:20:59 -05:00
Nick Mathewson
6867950432 Wrap all of the legacy guard code, and its users, in #ifdefs
This will make it easier to see what we remove down the line.
2016-12-16 11:06:22 -05:00
Nick Mathewson
3bcbbea350 More progress on bridge implementation with prop271 guards
Here we handle most (all?) of the remaining tasks, and fix some
bugs, in the prop271 bridge implementation.

  * We record bridge identities as we learn them.
  * We only call deprecated functions from bridges.c when the
    deprecated guard algorithm is in use.
  * We update any_bridge_descriptors_known() and
    num_bridges_usable() to work correctly with the new backend
    code. (Previously, they called into the guard selection logic.
  * We update bridge directory fetches to work with the new
    guard code.
  * We remove some erroneous assertions where we assumed that we'd
    never load a guard that wasn't for the current selection.

Also, we fix a couple of typos.
2016-12-16 11:06:18 -05:00
Nick Mathewson
53f248f6c9 Add some needed accessors/inspectors for bridge/guard convergence 2016-12-16 11:06:18 -05:00
Nick Mathewson
1d52ac4d3f Lay down some infrastructure for bridges in the New Guard Order.
This includes:
  * making bridge_info_t exposed but opaque
  * allowing guards where we don't know an identity
  * making it possible to learn the identity of a guard
  * creating a guard that lacks a node_t
  * remembering a guard's address and port.
  * Looking up a guard by address and port.
  * Only enforcing the rule that we need a live consensus to update
    the "listed" status for guards when we are not using bridges.
2016-12-16 11:06:18 -05:00
Nick Mathewson
dbbaa51518 Use the new guard notification/selection APIs throughout Tor
This patch doesn't cover every case; omitted cases are marked with
"XXXX prop271", as usual.  It leaves both the old interface and the
new interface for guard status notification, since they don't
actually work in the same way: the new API wants to be told when a
circuit has failed or succeeded, whereas the old API wants to know
when a channel has failed or succeeded.

I ran into some trouble with directory guard stuff, since when we
pick the directory guard, we don't actually have a circuit to
associate it with.  I solved that by allowing guard states to be
associated with directory connections, not just circuits.
2016-11-30 14:42:53 -05:00
Nick Mathewson
c74542c51a Add accessors as needed to repair compilation
The previous commit, in moving a bunch of functions to bridges.c,
broke compilation because bridges.c required two entry points to
entrynodes.c it didn't have.
2016-11-30 14:42:52 -05:00
Nick Mathewson
8da24c99bd Split bridge functions into a new module.
This patch is just:
   * Code movement
   * Adding headers here and there as needed
   * Adding a bridges_free_all() with a call to it.

It breaks compilation, since the bridge code needed to make exactly
2 calls into entrynodes.c internals.  I'll fix those in the next
commit.
2016-11-30 14:42:52 -05:00