Commit Graph

3 Commits

Author SHA1 Message Date
teor 4d608d3224
Stop doing thousands of time checks each time we connect to a peer (#3106)
* Stop checking the entire AddressBook for each connection attempt

* Stop redundant peer time checks within the address book

* Stop calling `Instant::now` 3 times for each address book update

* Only get the time once each time an address book method is called

* Update outdated comment

* Use an OrderedMap to efficiently store address book peers

* Add address book order tests
2021-12-03 15:09:43 -03:00
Janito Vaqueiro Ferreira Filho 11b5a33651
Security: Avoid reconnecting to peers that are likely unreachable (#3030)
* Add a `Duration32::from_days` constructor

Make it simpler to construct a `Duration32` representing a certain
number of days.

* Add `MetaAddr::was_not_recently_seen` method

A helper method to check if a peer was never seen before or if it was
last seen a long time ago. This will be one of the conditions to
consider a peer as unreachable.

* Add `MetaAddr::is_probably_unreachable` method

A helper method to check if a peer should be considered unreachable. It
is considered unreachable if recent connection attempts have failed and
it was not recently seen.

If a peer is considered unreachable, Zebra shouldn't attempt to connect
to it again.

* Do not keep trying to connect to unreachable peer

A peer is probably unreachable if it was last seen a long time ago and
if it's last connection attempt failed.

* Test `was_not_recently_seen`

Redo the calculation on arbitrary `MetaAddr`s.

* Test `is_probably_unreachable`

Redo the calculation on arbitrary `MetaAddr`s.

* Test if probably unreachable peers are ignored

Given an `AddressBook` with a list of arbitrary `MetaAddr`s, check that
none of the peers listed for a reconnection is probably unreachable.

* Rename unit test to improve clarity

Remove the double negative from the name.

Co-authored-by: teor <teor@riseup.net>

* Rename constant to `MAX_RECENT_PEER_AGE`

Make the purpose of the constant clearer.

Co-authored-by: teor <teor@riseup.net>

* Rename method to `last_seen_is_recent`

Remove the double negative from the name.

* Rename method to `is_probably_reachable`

Avoid having to negate the result of the method in security critical
filter.

* Move check into `is_ready_for_connection_attempt`

Make sure the check is used in any place that requires a peer that's
ready for a connection attempt.

* Improve test documention

Describe the goal of the test better.

Co-authored-by: teor <teor@riseup.net>

* Improve `is_probably_reachable` documentation

List the conditions as bullet points.

Co-authored-by: teor <teor@riseup.net>

* Document what happens when peers have no last seen time

Co-authored-by: teor <teor@riseup.net>
2021-11-10 23:51:22 +00:00
Janito Vaqueiro Ferreira Filho b68202c68a
Security: Zebra should stop gossiping unreachable addresses to other nodes, Action: re-deploy all nodes (#2392)
* Rename some methods and constants for clarity

Using the following commands:

```
fastmod '\bis_ready_for_attempt\b' is_ready_for_connection_attempt
  # One instance required a tweak, because of the ASCII diagram.
fastmod '\bwas_recently_live\b' has_connection_recently_responded
fastmod '\bwas_recently_attempted\b' was_connection_recently_attempted
fastmod '\bwas_recently_failed\b' has_connection_recently_failed
fastmod '\bLIVE_PEER_DURATION\b' MIN_PEER_RECONNECTION_DELAY
```

* Use `Instant::elapsed` for conciseness

Instead of `Instant::now().saturating_duration_since`. They're both
equivalent, and `elapsed` only panics if the `Instant` is somehow
synthetically generated.

* Allow `Duration32` to be created in other crates

Export the `Duration32` from the `zebra_chain::serialization` module.

* Add some new `Duration32` constructors

Create some helper `const` constructors to make it easy to create
constant durations. Add methods to create a `Duration32` from seconds,
minutes and hours.

* Avoid gossiping unreachable peers

When sanitizing the list of peers to gossip, remove those that we
haven't seen in more than three hours.

* Test if unreachable addresses aren't gossiped

Create a property test with random addreses inserted into an
`AddressBook`, and verify that the sanitized list of addresses does not
contain any addresses considered unreachable.

* Test if new alternate address isn't gossipable

Create a new alternate peer, because that type of `MetaAddr` does not
have `last_response` or `untrusted_last_seen` times. Verify that the
peer is not considered gossipable.

* Test if local listener is gossipable

The `MetaAddr` representing the local peer's listening address should
always be considered gossipable.

* Test if gossiped peer recently seen is gossipable

Create a `MetaAddr` representing a gossiped peer that was reported to be
seen recently. Check that the peer is considered gossipable.

* Test peer reportedly last seen in the future

Create a `MetaAddr` representing a peer gossiped and reported to have
been last seen in a time that's in the future. Check that the peer is
considered gossipable, to check that the fallback calculation is working
as intended.

* Test gossiped peer reportedly seen long ago

Create a `MetaAddr` representing a gossiped peer that was reported to
last have been seen a long time ago. Check that the peer is not
considered gossipable.

* Test if just responded peer is gossipable

Create a `MetaAddr` representing a peer that has just responded and
check that it is considered gossipable.

* Test if recently responded peer is gossipable

Create a `MetaAddr` representing a peer that last responded within the
duration a peer is considered reachable. Verify that the peer is
considered gossipable.

* Test peer that responded long ago isn't gossipable

Create a `MetaAddr` representing a peer that last responded outside the
duration a peer is considered reachable. Verify that the peer is not
considered gossipable.
2021-06-29 05:12:27 +00:00