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.
The peer will fail the channel on reconnect if we send an 'add' we
don't have balance for yet; we can avoid this issue by always sending
fulfills (+) before sending adds (-)
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>
Sending update_fee immediately after channel establishment seems to
upset LND, so work around it by deferring it. The reason we increase
the fee after establishment is because now we might need to close the
channel in a hurry due to htlcs, but until there are htlcs that's
unnecessary.
Fixes: #3596
Changelog-Changed: Added workaround for lnd rejecting our commitment_signed when we send an update_fee after channel confirmed.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We don't free the signatures in this case, and for some reason leak checking
on my build machine just found it:
MEMLEAK: 0x560f7dc69fc8'
label=channeld/gen_channel_wire.c:266:secp256k1_ecdsa_signature'
backtrace:'
ccan/ccan/tal/tal.c:442 (tal_alloc_)'
channeld/gen_channel_wire.c:266 (fromwire_channel_init)'
channeld/channeld.c:3060 (init_channel)'
channeld/channeld.c:3254 (main)'
parents:'
channeld/channeld.c:3227:struct peer'
MEMLEAK: 0x560f7dc6a288'
label=channeld/gen_channel_wire.c:272:secp256k1_ecdsa_signature'
backtrace:'
ccan/ccan/tal/tal.c:442 (tal_alloc_)'
channeld/gen_channel_wire.c:272 (fromwire_channel_init)'
channeld/channeld.c:3060 (init_channel)'
channeld/channeld.c:3254 (main)'
parents:'
channeld/channeld.c:3227:struct peer'
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
common/onion is going to need to use this for the case where it finds a blinding
seed inside the TLV. But how it does ecdh is daemon-specific.
We already had this problem for devtools/gossipwith, which supplied a
special hsm_do_ecdh(). This just makes it more general.
So we create a generic ecdh() interface, with a specific implementation
which subdaemons and lightningd can use.
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>
It's almost always "their_features" and "our_features" respectively, so
make those names clear.
Suggested-by: @cdecker
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Turns out that unnecessary: all callers can access the feature_set,
so make it much more like a normal primitive.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We roll the `elements_add_fee_output` function and the cropping of
overallocated arrays into the `bitcoin_tx_finalize` function. This is supposed
to be the final cleanup and compaction step before a tx can be sent to bitcoin
or passed off to other daemons.
This is the cleanup promised in #3491
At the moment, we store e.g. WIRE_TEMPORARY_CHANNEL_FAILURE, and then
lightningd has a large demux function which turns that into the correct
error message.
Such an enum demuxer is an anti-pattern.
Instead, store the message directly for output HTLCs; channeld now
sends us an error message rather than an error code.
For input HTLCs we will still need the failure code if the onion was
bad (since we need to prompt channeld to send a completely different
message than normal), though we can (and will!) eliminate its use in
non-BADONION failure cases.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We'll use this in the next patch for when we need to create errors to
send back to lightningd; most commonly when the channel doesn't have
capacity for the HTLC.
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 sets the nLockTime to the tip (and accordingly each input's nSequence to
0xfffffffe) for withdrawal transactions.
Even if the anti fee-sniping argument might not be valid until some time yet,
this makes our regular wallet transactions far less distinguishable from
bitcoind's ones since it now defaults to using native Segwit transactions
(like us). Moreover other wallets are likely to implement this (if they
haven't already).
Changelog-Added: wallet: withdrawal transactions now sets nlocktime to the current tip.
We could use sendonion to do this, but it actually takes a different path through
pay, and I wanted to test all of it, so I made a new dev flag.
We currently get upset with the response:
lightningd/pay.c:556: payment_failed: Assertion `!hout->failcode' failed.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
These messages may be exchanged between the master and any daemon. For now
these are just the daemons that a peer may be attached to at any time since
the first example of this is the custommsg infrastructure.
Generally I prefer structures over u8, since the size is enforced at
runtime; and in several places we were doing conversions as the code
using Sphinx does treat struct secret as type of the secret.
Note that passing an array is the same as passing the address, so
changing from 'u8 secret[32]' to 'struct secret secret' means various
'secret' parameters change to '&secret'. Technically, '&secret' also
would have worked before, since '&' is a noop on array, but that's
always seemed a bit weird.
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>
We still close the channel if we *send* an error, but we seem to have hit
another case where LND sends an error which seems transient, so this will
make a best-effort attempt to preserve our channel in that case.
Some test have to be modified, since they don't terminate as they did
previously :(
Changelog-Changed: quirks: We'll now reconnect and retry if we get an error on an established channel. This works around lnd sending error messages that may be non-fatal.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Thanks to @t-bast, who made this possible by interop testing with Eclair!
Changelog-Added: Protocol: can now send and receive TLV-style onion messages.
Changelog-Added: Protocol: can now send and receive BOLT11 payment_secrets.
Changelog-Added: Protocol: can now receive basic multi-part payments.
Changelog-Added: RPC: low-level commands sendpay and waitsendpay can now be used to manually send multi-part payments.
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>
The `channel_got_commitsig` we send the lightningd also implies we sent
the revoke_and_ack, as an optimization. It doesn't currently matter,
since channel_sending_revoke_and_ack doesn't do anything important to the
state, but that changes once we start uploading the entire fee_states.
So now we move our state machine *before* sending to lightningd, in
preparation for sending fee_states too.
Unfortunately, we need to marshall the info to send before we
increment the state, as lightningd expects that.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This uses the same state machine as HTLCs, but they're only
ever added, not removed. Since we can only have one in each
state, we use a simple array; mostly NULL.
We could make this more space-efficient by folding everything into the
first 5 states, but that would be more complex than just using the
identical state machine.
One subtlety: we don't send uncommitted fee_states over the wire.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Now "raw_payload" is always the complete string (including realm or length
bytes at the front).
This has several effects:
1. We can receive an decrypt an onion which is grossly malformed.
2. We can still hand this to the htlc_accepted hook.
3. We then fail it unless the htlc_accepted accepts it manually.
4. The createonion API now takes the raw payload, and does not know
anything about "style".
The only caveat is that the sphinx code needs to know the payload
length: we have a call for that, which simply tells it to copy the
entire onion (and treat us as the final node) if it's invalid.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>