This also means we subtract 660 satoshis more everywhere we subtract
the base fee (except for mutual close, where the base fee is still
used).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
HTLC fees increase (larger weight), and the fee paid by the opener
has to include the anchor outputs (i.e. 660 sats).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Update the `bitcoin_tx_add_input` interface to accept a witness script
and or scriptPubkey.
We save the amount + witness script + witness program (if known) to
the PSBT object for a transaction when creating an input.
Previously we've used the term 'funder' to refer to the peer
paying the fees for a transaction; v2 of openchannel will make
this no longer true. Instead we rename this to 'opener', or the
peer sending the 'open_channel' message, since this will be universally
true in a dual-funding world.
Note that it's channeld which calculates the shared secret, too. This
minimizes the work that lightningd has to do, at cost of passing this
through.
We also don't yet save the blinding field(s) to the database.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We currently abuse the added_htlc and failed_htlc messages to tell channeld
about existing htlcs when it restarts. It's clearer to have an explicit
'existing_htlc' type which contains all the information for this case.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Instead of making it ourselves, lightningd does it. Now we only have
two cases of failed htlcs: completely malformed (BADONION), and with
an already-wrapped onion reply to send.
This makes channeld's job much simpler.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
For incoming htlcs, we need failure details in case we need to
re-xmit them. But for outgoing htlcs, lightningd is telling us it
already knows they've failed, so we just need to flag them failed
and don't need the details.
Internally, we set the ->fail to a dummy non-NULL value; this is
cleaned up next.
This matters for the next patch, which moves onion handling into
lightningd.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Add new check if we're funder trying to add HTLC, keeping us
with enough extra funds to pay for another HTLC the peer might add.
We also need to adjust the spendable_msat calculation, and update
various tests which try to unbalance channels. We eliminate
the now-redundant test_channel_drainage entirely.
Changelog-Fixed: Corner case where channel could become unusable (https://github.com/lightningnetwork/lightning-rfc/issues/728)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This makes it clear we're dealing with a message which is a wrapped error
reply (needing unwrap_onionreply), not an already-wrapped one.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is the final step: we pass the complete fee_states to and from
channeld.
Changelog-Fixed: "Bad commitment signature" closing channels when we sent back-to-back update_fee messages across multiple reconnects.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
These used to be necessary as we could have feerate changes which
we couldn't track: now we do, we don't need these flags.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is an intermediary step: we still don't save it to the database,
but we do use the fee_states struct to track it internally.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Travis randomly picked up an error in test_feerate_stress:
**BROKEN** 0266e4598d1d3c415f572a8488830b60f7e744ed9235eb0b1ba93283b315c03518-channeld-chan#1: Cannot add htlc #0 10000msat to LOCAL (version a2541b9-modded)
This is because it hit an unlikely corner case involving applying multiple HTLCs
(similar to the previous c96cee9b8d).
In this case, the test sends a 500,000,000 "balancing" setup payment L1->L2.
It waits for L2 to get the preimage (which is the when pay() helper returns),
but crucially, it starts spamming with HTLCs before that HTLC is completely
removed.
From L2's point of view, the setup HTLC is in state RCVD_REMOVE_REVOCATION;
gone from L1's commitment tx, but still waiting for the commitment_signed
from L1 to remove it from L2's.
Note that each side keeps a local and remove view of both sides' current
balances: at this point, L2's view is REMOTE: "500,000,000 to L1, 499,900,000
to L2", LOCAL: "500,000,000 to L1, 0 to L2".
L2 sends a 10,000 msat HTLC to L1: legal, since L1 will allow it,
then the commitment_signed. L1 sends the revoke-and-ack for this,
*then* belatedly follows with the commitment_signed which both completes the
removal of the setup HTLC and adds the new one.
But L2 processes the HTLCs in hashtable (i.e. random) order: so if it
tries to apply its own HTLC first, it freaks out because it doesn't have
funds in its local view.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Fixed: Unlikely corner case is simultanous HTLCs near balance limits fixed.
A long time ago (93dcd5fed7), I
simplified the htlc reload code so it adjusted the amounts for HTLCs
in id order. As we presumably allowed them to be added in that order,
this avoided special-casing overflow (which was about to deliberately
be made harder by the new amount_msat code).
Unfortunately, htlc id order is not canonical, since htlc ids are
assigned consecutively in both directions! Concretely, we can have two HTLCs:
HTLC #0 LOCAL->REMOTE: 500,000,000 msat, state RCVD_REMOVE_REVOCATION
HTLC #0 REMOTE->LOCAL: 10,000 msat, state SENT_ADD_COMMIT
On a new remote-funded channel, in which we have 0 balance, these
commits *only* work in this order. Sorting by HTLC ID is not enough!
In fact, we'd have to worry about redemption order as well, as that
matters.
So, regretfully, we offset the balances halfway to UINT64_MAX, then check
they didn't underflow at the end. This loses us this one sanity check,
but that's probably OK.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
WIRE_REQUIRED_CHANNEL_FEATURE_MISSING anticipates a glorious Wumbo future,
and is closer to correct (it's a PERM failure).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The largest change is inside hsmd: it hands a null per-commitment key
to the wallet to tell it to spend the to_remote output.
It can also now resolve unknown commitments, even if it doesn't have a
possible_remote_per_commitment_point from the peer.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rather than reaching into data structures, let them register their own
callbacks. This avoids us having to expose "memleak_remove_xxx"
functions, and call them manually.
Under the hood, this is done by having a specially-named tal child of
the thing we want to assist, containing the callback.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The way we build transactions, serialize them, and compute fees depends on the
chain we are working on, so let's add some context to the transactions.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
And clean up some dev ones which actually happen (mainly by calling
channel_fail_permanent which logs UNUSUAL, rather than
channel_internal_error which logs BROKEN).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We track whether each change is affordable as we go;
test_channel_drainage got us so close that the difference mattered; we
hit an assert when we tried to commit the tx and realized we couldn't
afford it.
We should not be trying to add an HTLC if it will result in the funder
being unable to afford it on either the local *or remote* commitments.
Note the test still "fails" because it refuses to send the final
payment.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
1. Rename channel_funding_locked to channel_funding_depth in
channeld/channel_wire.csv.
2. Add minimum_depth in struct channel in common/initial_channel.h and
change corresponding init function: new_initial_channel().
3. Add confirmation_needed in struct peer in channeld/channeld.c.
4. Rename channel_tell_funding_locked to channel_tell_depth.
5. Call channel_tell_depth even if depth < minimum, and still call
lockin_complete in channel_tell_depth, iff depth > minimum_depth.
6. channeld ignore the channel_funding_depth unless its >
minimum_depth(except to update billboard, and set
peer->confirmation_needed = minimum_depth - depth).
We need to do it in various places, but we shouldn't do it lightly:
the primitives are there to help us get overflow handling correct.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
As a side-effect of using amount_msat in gossipd/routing.c, we explicitly
handle overflows and don't need to pre-prune ridiculous-fee channels.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
