We already removed the on-chain states, now we remove the "clearing" state
(which wasn't fully implemented anyway).
This turns into two smaller state machines: one for clearing, which
still allows HTLCs to be failed and fulfilled, and one for mutual
close negotiation which only allows close_signature messages.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Previous to this, we kept the remote side's 'struct channel_state'
backwards: peer->remote.commit->cstate.side[OURS] was their HTLCs,
and [THEIRS] was our HTLCs. This made some things easier, but was
horrible for readability.
This inverts things so we keep track of the remote side's state from
our point of view: [OURS] is ours, [THEIRS] is theirs. Which makes
much more sense.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
As per lightning-rfc commit 8ee09e749990a11fa53bea03d5961cfde4be4616,
we remove the acks from the protocol now they're no longer needed (and
all the infrastructure).
We also place the commit number in the commit_info where it logically
belongs, removing it from the peer struct.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
From BOLT#2 (rev 8ee09e749990a11fa53bea03d5961cfde4be4616):
Thus each node (conceptually) tracks:
...
3. Two *unacked changesets*: one for the local commitment (their proposals) and one for the remote (our proposals)
4. Two *acked changesets*: one for the local commitment (our proposals, acknowledged) and one for the remote (their proposals, acknowledged).
(Note that an implementation MAY optimize this internally, for
example, pre-applying the changesets in some cases).
In our case, we apply the unacked changes immediately into
staging_cstate, and save them in an unacked_changes array. That array
gets applied to staging_cstate as soon as it's acked (we only allow
one outstanding update_commit, so we only need one array).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
While useful for testing, it doesn't make sense to have an explicit commit
command; we should commit whenever there are outstanding changes.
We have a 10ms timer to allow limited batching, however.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is just generally good practice. All our other txs are single-input,
so we've not needed to permute inputs before.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Once we see an on-chain tx, we ignore the state machine and handle it
as per the onchain.md draft. This specifies a *resolution* for each
output, and we're done when they're irrevocable.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It's not quite true: if we offer the anchor, we have a commitinfo
without their signature yet. So make it a pointer again. Since we
always allocate struct commit_info with talz, it starts as a NULL
pointer.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is called when an HTLC times out, and we need to send it back to
ourselves. We also adjust the locktime, since in practice we should
refuse an HTLC less than our locktime.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We don't report conflicts, just depths. So we report 0 if it's in a
main chain which loses to another, otherwise it's always positive.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Since bitcoind doesn't propagate non-main chains, there's little point
trying to be smart when we see them. This simplifies things immensely.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It's primitive, but we re-broadcast any txs not included in the main
chain every time the tip moves. We only track transactions we are
watching, but that turns out to cover every transaction we generate
anyway.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We watch the anchor output, and separate it into different cases.
This is simpler with segwit (txids are known before sigs), but we also
had missed the case of our own commit transaction spend.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
There's no reason to, it's a simple p2wpkh to our key.
We still spend the "to-us" from our commit tx, since it could be
theoretically be stolen by the revocation value, and it's a complex
p2wsh which a normal wallet won't have the information to spend.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Turns out that we want to pass information about the commit info, the
HTLC number and (sometimes) the R value, so create a struct for that.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
You can't re-enter the state machine from a callback, so this allows you
to queue an input for when it returns.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Since 43729c6856 (protocol: add output script to close_clearing message.)
the close scripts are not p2sh, but arbitrary. Fix the close tx matching.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We just use a p2sh to a single address for the moment, but that's simply for
non-segwit wallets; we'll pay to whatever the other side specifies.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Since any transaction with all segregated-witness inputs is non-malleable,
and all our transactions are that, we can remove normalized txids.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rather than p2sh of a 2of2, it's now a version 0 witness program.
This means that the commit transaction input and mutual close
transaction input are both different.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
There isn't a single blockhash; we may be on multiple forks. But the one
caller which cares is commit_tx_depth(), which wants to know if the tx is
spendable yet. So that uses get_last_mediantime().
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>