It usually means we're missing something, but there's no way to ask what.
Simply start a broad scid probe.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This should give more reliable results, though it risks us getting
suckered into always consulting the same peer.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We assume that the time for gossip propagation is < 10 minutes, so by
going back that far from last gossip we won't miss anything,
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It's simple: if we wouldn't accept the timestamp we see, don't put
the channel in the stale_scid_map.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Just try to choose another. Under Travis, this causes many failures due
to slowness (they only get 10 seconds in -dev mode).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We eliminate the "need peer" states and instead check if the
random_peer_softref has been cleared.
We can also unify our restart handlers for all these cases; even the
probe_scids case, by giving gossip credit for the scids as they come
in (at a discount, since scids are 8 bytes vs the ~200 bytes for
normal gossip messages).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Build up a map of short_channel_ids which we have old info for (only
if peer supports gossip_query_ex).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This asks peers to append the timestamps or checksums: if it has
gossip_query_ex support, it will, otherwise it's ignored.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If the peer supports `gossip_query_ex` we can use query_flags to simply
request the node_announcements when probing for nodes, rather than
getting everything. If a peer doesn't support `gossip_query_ex` then
it's harmless to add it.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We pick some nodes which don't seem to have node_announcements and we
ask a channel associated with them. Again, if this reveals more
node_announcements, we probe for twice as many next time.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If we have any unknown short_channel_ids, we ask a random peer for
those channels. Once it responds, we probe again for a small random
range in case more are missing, again enlarging if we find some.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Instead of a linear array which is fairly inefficient if it turns out
we know nothing at all.
We remove the gossip_missing() call by changing the api to
remove_unknown_scid() to include a flag as to whether the scid turned
out to be real or not.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Once we've finished streaming gossip from the first peer, we ask a
random peer (maybe the same one) for all short_channel_ids in the last
6 blocks from the latest channel we know about.
If this reveals new channels we didn't know about, we expand the probe
by a factor of 2 each time.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The seeker starts by asking a peer (the first peer!) for all gossip
since a minute before the modified time of the gossip store.
This algorithm is enhanced in successive patches.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Since we have to validate, there can be a delay (and peer might
vanish) between receiving the gossip and actually confirming it, hence
the use of softref.
We will use this information to check that the peers are making progress
as we start asking them for specific information.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is the modified-time of the file. We have to store it internally
since we overwrite the gossip file with compaction on startup.
This means the "are we behind on gossip?" heuristic is no longer inside
gossip_store.c, which is cleaner.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We now have a pointer to chainparams, that fails valgrind if we do anything
chain-specific before setting it.
Suggested-by: Rusty Russell <@rustyrussell>
We do this by keeping a current and an old map, and moving the current to old
every hour or 10,000 entries.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This encoding scheme is no longer just used for short_channel_ids, so make
the names more generic.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I was seeing some accidental pruning under load / Travis, and in
particular we stopped accepting channel_updates because they were 103
seconds old. But making it too long makes the prune test untenable,
so restore a separate flag that this test can use.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The only real change is dump_gossip() used to call
maybe_create_next_scid_reply(), but now I've simply renamed
that to maybe_send_query_responses() and we call it directly.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Now we queue them, we should place a limit. It's not the worst thing in
the world if we discard them (we'll catch up eventually), but we should
try not to in case we're just a bit behind.
Our behaviour here is also O(n^2) so we don't want a massive queue
anyway.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The first one means we don't discard channels just because we're not
synced, and the second is implied by the spec: don't accept
channel_announcement if the channel isn't 6 deep. Since LND defers in
such cases, we do too (unless it's newer than the current block, in
which case we simply discard). Otherwise there's a risk that a slow
node might discard valid gossip.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This will let gossipd be more intelligent about gossiping before we're
synced, and also it might know how far behind we are.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Happened under Travis with --dev-fast-gossip (90 second prune time), but can
happen anyway if gossip is almost 2 weeks old when we receive it:
2019-09-20T19:16:51.367Z DEBUG lightning_gossipd(20972): Received node_announcement for node 022d223620a359a47ff7f7ac447c85c46c923da53389221a0054c11c1e3ca31d59
2019-09-20T19:16:51.376Z DEBUG lightning_gossipd(20972): Ignoring node_announcement timestamp 1569006918 for 022d223620a359a47ff7f7ac447c85c46c923da53389221a0054c11c1e3ca31d59
2019-09-20T19:16:51.669Z **BROKEN** lightning_gossipd(20972): pending node_announcement 01013094af771d60f4de69bb39ce045e4edf4a06fe6c80078dfa4fab58ab5617d6ad4fa34b6d3437380db0a8293cea348bbc77f714ef71fcd8515bfc82336667441f00005d852546022d223620a359a47ff7f7ac447c85c46c923da53389221a0054c11c1e3ca31d59022d2253494c454e544152544953542d633961313734610000000000000000000000000000 malformed? (version c9a174a)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>