Well, it's generated by shachain, so technically it is a sha256, but
that's an internal detail. It's a secret.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Just have a "new depth" callback, and let channeld do the right thing.
This makes the channeld paths a bit more straightforward.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If channeld dies for some reason (eg, reconnect) and we didn't yet announce
the channel, we can miss doing so. This is unusual, because if lightningd
restarts it rearms the callback which gives us funding_locked, so it only
happens if just channel dies before sending the announcement message.
This problem applies to both temporary announcement (for gossipd) and
the real one. For the temporary one, simply re-send on startup, and
remote the error msg gossipd gives if it sees a second one. For the
real one, we need a flag to tell us the depth is sufficient; the peer
will ignore re-sends anyway.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
(This was sitting in my gossip-enchancement patch queue, but it simplifies
this set too, so I moved it here).
In 94711969f we added an explicit gossip_index so when gossipd gets
peers back from other daemons, it knows what gossip it has sent (since
gossipd can send gossip after the other daemon is already complete).
This solution is insufficient for the more general case where gossipd
wants to send other messages reliably, so replace it with the other
solution: have gossipd drain the "gossip fd" which the daemon returns.
This turns out to be quite simple, and is probably how I should have
done it originally :(
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We missed it in some corner cases where we crashed/were killed between
being told of the lockin and sending the channel_normal_operation message.
When we were restarted, we were told both sides were locked in already,
so we never updated the state.
Pull the entire "tell channeld" logic into channel_control.c, and make
it clear that we need to keep waching if we cant't tell channeld. I think
we did get this correct in practice, since funding_announce_cb has the
same test, but it's better to be clear.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This simplifies things, and means it's always in the database. Our
previous approach to creating it on the fly had holes when it was
created for onchaind, causing us to use another every time we
restarted.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It's just a sha256_double, but importantly when we convert it to a
string (in type_to_string, which is used in logging) we use
bitcoin_blkid_to_hex() so it's reversed as people expect.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It's just a sha256_double, but importantly when we convert it to a
string (in type_to_string, which is used in logging) we use
bitcoin_txid_to_hex() so it's reversed as people expect.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When gossipd sends a message, have a gossip_index. When it gets back a
peer, the current gossip_index is included, so it can know exactly where
it's up to.
Most of this is mechanical plumbing through openingd, channeld and closingd,
even though openingd and closingd don't (currently) read gossip, so their
gossip_index will be unchanged.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The master now hands channeld either an error code, and channeld
generates the error message, or an error message relayed from another
node to pass through.
This doesn't fill in the channel_update yet: we need to wire up gossipd
to give us that.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Currently lightningd does this, but channeld is perfectly capable of doing it.
channeld is also in a far better position to add channel_updates to it.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We only send them when we're not awaiting revoke_and_ack: our
simplified handling can't deal with multiple in flights.
Closes: #244
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
There is a race we see sometimes under valgrind on Travis which shows
gossipd receiving the node_announce from master before it reads the
channel_announce from channeld, and thus fails. The simplest solution
is to send the channel_announce and channel_update to master as well,
so it can ensure it sends them to gossipd in order
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We were sending a channeld message to onchaind, which was v. confusing
due to overlap. We make all the numbers distinct, which means we can
also add an assert() that it's valid for that daemon, which catches
such errors immediately.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This change is really to allow us to have a --dev-fail-on-subdaemon-fail option
so we can handle failures from subdaemons generically.
It also neatens handling so we can have an explicit callback for "peer
did something wrong" (which matters if we want to close the channel in
that case).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is what it actually is, and makes it clearer when we refer to the
spec. It's the commitment we're currently updating, which is the next
commitment.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We keep the scriptpubkey to send until after a commitment_signed (or,
in the corner case, if there's no pending commitment). When we
receive a shutdown from the peer, we pass it up to the master.
It's up to the master not to add any more HTLCs, which works because
we move from CHANNELD_NORMAL to CHANNELD_SHUTTING_DOWN.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This matters in one case: channeld receiving a bad message is a
permenant failure, whereas losing a connection is transient.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We need the old remote per_commitment_point so we can validate the
per_commitment_secret when we get it.
We unify this housekeeping in the master daemon using
update_per_commit_point().
This patch also saves whether remote funding is locked, and disallows
doing that twice (channeld should ignore it).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
There are two ways we can do retransmission on reconnect: re-derive
what we would have sent, or remember it and simply re-send. The
rederivation is difficult: unwinding state depends on whether we sent
a revoke_and_ack before or after the commitment_signed, and unwinding
a revoke_and_ack would require us to remember HTLCs we would have
normally forgotten at this point.
So we simply tell the master to remember the old signatures for us,
and hand them back in case we need to re-send.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
In the case where we can't decrypt the onion, we can't fail it in the
normal way (which is encrypted using the onion shared secret), we need
to respond with a update_fail_malformed_htlc message.
Moreover, we need to remember this for persistence. This means that
we really have three conclusions for an HTLC: fulfilled, failed,
malformed. Fix up the logic everywhere which assumed failed or
fulfilled.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It's easiest to have the master keep the last commit we sent, for
re-transmission. We could recalculate it, but it's made more difficult
by the before/after revoke case.
And because revoke_and_ack changes the channel state, we need to
remember which order we sent them in for re-transmission.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It needs to save them to the db in case of restart; this means we tell
it about funding_locked, as well as the next_per_commit_point given
in revoke_and_ack.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The channel daemon gets the shared secrets from the HSM to save
the master daemon some work. It used to hand these over at
revoke_and_ack receive, which is when the master daemon needs them.
However, it's a bit simpler to hand them over when we first tell
the master about the incoming HTLC (the first commitsig).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rusty Russell
practicalswift
Christian Decker