We were incorrectly saving the *remote's* commitment transaction as the
'last_tx' for a peer, not our own local one.
When we applied the 'remote_commit_sig' to it, it would fail since the
remote's signature doesn't validate for their commitment transaction.
This will make it possible to do RBF, since we can re-start the opening
process in dualopend while waiting for lock-in.
Note the new channel states are being used, DUALOPEND_INIT and
DUALOPEND_AWAITING_LOCKIN, to differentiate from openingd/channeld opens
This is vital for calculating merkle trees; I previously used
towire+fromwire to get this!
Requires generation change so we can magic the ARRAY_SIZE var (the C
pre-processor can't uppercase things).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We let the plugin decide what feerate to accept/whether or not to add
funds to the open. To aid this decision, we also send the plugin what we
(c-lightning) currently have as our max and min acceptable feerates.
We also now use these as our default for max/min acceptable feerate
range when sending an openchannel offer to a peer.
In the future, it might be a good idea to make these more easily
changeable, either via a config setting (?) or a command param.
Note that check-whitespace and check-bolt already do this, so we
can eliminate redundant lines in common/Makefile and bitcoin/Makefile.
We also include the plugin headers in ALL_C_HEADERS so they get
checked.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Fixes#4140
Reported-By: @PsySc0rpi0n
Changelog-Fixed: openingd now uses the correct dust limit for determining the allowable floor for a channel open (affects fundee only)
This is handy/necessary for getting multifundchannel to work, as we need
to know what output to tell all the other peers about.
Changelog-Added: Experimental!! JSON-RPC: openchannel_init returns a field `funding_serial` that indicates the serial_id of the funding output in the provided PSBT
`check_balances` had a weird interface because it was meant to be able
to be used at any 'intermediate' point to verify that a single side had
a valid inputs/output balance.
This was worse than useless. Now it just straight checks for both sides'
balances are correct and that both sides pay their fees. Called after
transaction is constructed.
There's a few structs/wire calls that only exist under experimental features.
These were in a common file that was shared/used a bunch of places but
this causes problems. Here we move one of the problematic methods back
into `openingd`, as it's only used locally and then isolate the
references to the `witness_stack` in a new `common/psbt_internal` file.
This lets us remove the iff EXP_FEATURES inclusion switches in most of
the Makefiles.
Rusty pointed out that having an empty channel_id is suboptimal; adding
another call is probably the right idea rather than re-using an existing
one.
Suggested-By: @rustyrussell
There are 3 commands for opening a channel with dualfunding.
`openchannel_init` is the first of these.
It initializes the open-channel dialog, and stops once we've run out of
updates (input/outputs) to send to the peer.
`test_opening_tiny_channel` fails if EXPERIMENTAL_FEATURES is on because
we don't include the anchor in our reserve if we're the channel opener.
Seems fine to include in all cases?
1. Rename memleak_enter_allocations to memleak_find_allocations.
2. Unify scanning for pointers into memleak_remove_region / memleak_remove_pointer.
3. Document the functions.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
clang did the hard work here:
openingd/dualopend.c:958:42: error: result of comparison of constant 'WIRE_DUAL_OPEN_FAIL' (7003) with expression of type 'u8' (aka 'unsigned char') is always false
[-Werror,-Wtautological-constant-out-of-range-compare]
if ((msg_type = fromwire_peektype(msg)) == WIRE_DUAL_OPEN_FAIL) {
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~
Co-Authored-by: the clang compiler
Signed-off-by: Antoine Poinsot <darosior@protonmail.com>
We can use a fixed value and close the channel if they don't cover their
amount; this wasn't really helping with anything other than setting a
floor for an expected feerate
Greatly simplify the changeset API. Instead of 'diff' we simply generate
the changes.
Also pulls up the 'next message' method, as at some point the
interactive tx protocol will be used for other things as well
(splices/closes etc)
Suggested-By: @rustyrussell
v2 channel open uses a different method to derive the channel_id, so now
we save it to the database so that we dont have to remember how to
derive it for each.
includes a migration for existing channels
There's a lot of it, and it means we can't `make check-source` on
these files.
Also bring bolt quotes up-to-date.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It's now only needed by devtools/mkfunding, so include a reduced one
there, and this also means we remove tx_spending_utxos().
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This avoids overwriting the ones in git, and generally makes things neater.
We have convenience headers wire/peer_wire.h and wire/onion_wire.h to
avoid most #ifdefs: simply include those.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We're going to make experimental versions of these completely separate files.
Also remove the dependency on the Makefile itself: it simply causes
unnecessary churn. We can always force-rebuild when we change a rule.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
And document exactly what it does: insist that an HTLC can pass of
this value (module assumptions of feerate).
Note that we remove the "is_opener" test from the capacity calculation
for anchor fees: it doesn't matter which side it is, someone has to pay
for anchor fees to it deducts from capacity.
This change breaks the test, which we rewrite.
Changelog-Changed: config: `min-capacity-sat` is now stricter about checking usable capacity of channels.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We create ALL_PROGRAMS, ALL_TEST_PROGRAMS, ALL_C_SOURCES and
ALL_C_HEADERS. Then the toplevel Makefile knows which are
autogenerated (by wildcard), so it can have all the rules to clean
them or check the source as necessary.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Note that other directories were explicitly depending on the generated
file, instead of relying on their (already existing) dependency on
$(LIGHTNINGD_HSM_CLIENT_OBJS), so we remove that.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Includes:
psbt: Use renamed functions for new wally version
psbt: Set the transaction directly to avoid script workarounds
psbt: Use low-S grinding when computing signatures
tx: Use wally_tx_clone from libwally now that its exported
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>
It's not all that rare to do these operations, and requiring annotations
for it is a little painful.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Fixes: #3815
Changelog-Fixed: Fixed a deviation from BOLT#2: if both nodes advertised `option_upfront_shutdown_script` feature: MUST include ... a zero-length `shutdown_scriptpubkey`.
The main change here is that the previously-optional open/accept
fields and reestablish fields are now compulsory (everyone was
including them anyway). In fact, the open/accept is a TLV
because it was actually the same format.
For more details, see lightning-rfc/f068dd0d8dfa5ae75feedd99f269e23be4777381
Changelog-Removed: protocol: support for optioned form of reestablish messages now compulsory.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
now that witness script data is saved into the tx/psbt which is
serialized across the wire, there's no reason to use witscript to do
this. good bye witscript!
Since we now over-write the wally malloc/free functions, we need to do
so for tests as well. Here we pull up all of the common setup/teardown
logic into a separate place, and update the tests that use libwally to
use the new common_setup core
Changelog-None
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.
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>
Note that now we check capacity once we've figured out which peer, which
broke a test (we returned "unknown peer" instead of "capacity exceeded"),
so we rework that too.
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 don't compile with NDEBUG defined, but if we did, this code would
vanish. I did a quick audit, inspired by @ZmnSCPxj.
I actually hacked up something to compile with NDEBUG (many unused vars
resulted, and of course unit tests are allowed to rely on assert()), and
after this the testsuite still passes.
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.
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>
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>
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>
test_openchannel_hook_1:
MEMLEAK: 0x557593c164e8'
label=wire/fromwire.c:320:char[]'
backtrace:'
ccan/ccan/tal/tal.c:437 (tal_alloc_)'
ccan/ccan/tal/tal.c:466 (tal_alloc_arr_)'
wire/fromwire.c:320 (fromwire_wirestring)'
openingd/gen_opening_wire.c:205 (fromwire_opening_got_offer_reply)'
openingd/openingd.c:1067 (fundee_channel)'
openingd/openingd.c:1279 (handle_peer_in)'
openingd/openingd.c:1535 (main)'
parents:
fromwire_opening_got_offer_reply() allocates two fields off NULL:
err_reason and our_upfront_shutdown_script. err_reason is used
immediately afterwards (and was the leak detected here), so fixing
that is easy.
To fix the leak of our_upfront_shutdown_script, it makes sense to simply
make it a member of 'state'.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rounds out the application of `upfront_shutdown_script`, allowing
an accepting node to specify a close_to address.
Prior to this, only the opening node could specify one.
Changelog-Added: Plugins: Allow the 'accepter' to specify an upfront_shutdown_script for a channel via a `close_to` field in the openchannel hook result
--dev-force-tmp-channel-id flag takes a 64-character hex string
to use as the temporary channel id. Useful for spec tests
[ Fixed crash in non-DEVELOPER mode --RR ]
Changelog-None
Takes advantage of upfront-shutdown-script to permit users to
specify the close-to address for a channel at open, by adding
a `close_to` field to `fundchannel_start`.
Note that this only is in effect if `fundchannel_start` returns
with `close_to` set -- otherwise, peer doesn't
support `option_upfront_shutdown_script`.
This is mainly an internal-only change, especially since we don't
offer any globalfeatures.
However, LND (as of next release) will offer global features, and also
expect option_static_remotekey to be a *global* feature. So we send
our (merged) feature bitset as both global and local in init, and fold
those bitsets together when we get an init msg.
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>
Valgrind error file: valgrind-errors.112365
==112365== Conditional jump or move depends on uninitialised value(s)
==112365== at 0x1105E0: main (openingd.c:1504)
==112365==
==112365== Conditional jump or move depends on uninitialised value(s)
==112365== at 0x110604: main (openingd.c:1507)
==112365==
==112365== Conditional jump or move depends on uninitialised value(s)
==112365== at 0x110628: main (openingd.c:1510)
==112365==
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It's generally clearer to have simple hardcoded numbers with an
#if DEVELOPER around it, than apparent variables which aren't, really.
Interestingly, our pruning test was always kinda broken: we have to pass
two cycles, since l2 will refresh the channel once to avoid pruning.
Do the more obvious thing, and cut the network in half and check that
l1 and l3 time out.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When the peer sends back an error, we return null, but sending
a NULL message back to lightningd causes a parsing error on their
side. negotiation_failed already calls back the peer, all we need
to do here is exit.
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>
It probably doesn't matter to "fundchannel_cancel" exactly why the
fundchannel didn't work (though it can read the error msg), and we
should always fail any pending fundchannel_complete command.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Big wiring re-org for funding-continue
In openingd, we move the 'persistent' state (their basepoints,
pubkey, and the minimum_depth requirement for the opening tx) into
the state object. We also look to keep code-reuse between
'continue' and normal 'fundchannel' as high as possible. Both
of these call the same 'fundchannel_reply' at the end.
In opening_control.c, we remap fundchannel_reply such that it is
now aware of the difference between an external/internally funded
channel open. It's the same return path, with the difference that
one finishes making and broadcasting the funding transaction; the
other is skips this.
Add an RPC method (not working at the moment) called
`fundchannel_continue` that takes as its parameters a
node_id and a txid for a transaction (that ostensibly has an output
for a channel)
For the `fundchannel_cancel` we're going to want
to 'successfully' fail a funding channel operation. This allows
us to report it a failure back as an RPC success, instead of
automatically failing the RPC request.
This means we intercept the peer's gossip_timestamp_filter request
in the per-peer subdaemon itself. The rest of the semantics are fairly
simple however.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Keeping the uintmap ordering all the broadcastable messages is expensive:
130MB for the million-channels project. But now we delete obsolete entries
from the store, we can have the per-peer daemons simply read that sequentially
and stream the gossip itself.
This is the most primitive version, where all gossip is streamed;
successive patches will bring back proper handling of timestamp filtering
and initial_routing_sync.
We add a gossip_state field to track what's happening with our gossip
streaming: it's initialized in gossipd, and currently always set, but
once we handle timestamps the per-peer daemon may do it when the first
filter is sent.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Encapsulating the peer state was a win for lightningd; not surprisingly,
it's even more of a win for the other daemons, especially as we want
to add a little gossip information.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We ask gossipd for the channel_update for the outgoing channel; any other
messages it sends us get queued for later processing.
But this is overzealous: we can shunt those msgs to the peer while
we're waiting. This fixes a nasty case where we have to handle
WIRE_GOSSIPD_NEW_STORE_FD messages by queuing the fd for later.
This then means that WIRE_GOSSIPD_NEW_STORE_FD can be handled
internally inside handle_gossip_msg(), since it's always dealt with
the same, simplifying all callers.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Instead of lightningd telling us when it's ready, we ask it.
This also provides an opportunity to have a plugin hook at this point.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
My raspberry pi node hung up on my other node:
lightning_openingd-... chan #1: Got bad message from gossipd: 0db1
This is because we didn't handle that message in one path.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Instead of reading the store ourselves, we can just send them an
offset. This saves gossipd a lot of work, putting it where it belongs
(in the daemon responsible for the specific peer).
MCP bench results:
store_load_msec:28509-31001(29206.6+/-9.4e+02)
vsz_kb:580004-580016(580006+/-4.8)
store_rewrite_sec:11.640000-12.730000(11.908+/-0.41)
listnodes_sec:1.790000-1.880000(1.83+/-0.032)
listchannels_sec:21.180000-21.950000(21.476+/-0.27)
routing_sec:2.210000-11.160000(7.126+/-3.1)
peer_write_all_sec:36.270000-41.200000(38.168+/-1.9)
Signficant savings in streaming gossip:
-peer_write_all_sec:48.160000-51.480000(49.608+/-1.1)
+peer_write_all_sec:35.780000-37.980000(36.43+/-0.81)
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>
Basically we tell it that every field ending in '_msat' is a struct
amount_msat, and 'satoshis' is an amount_sat. The exceptions are
channel_update's fee_base_msat which is a u32, and
final_incorrect_htlc_amount's incoming_htlc_amt which is also a
'struct amount_msat'.
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>
They're generally used pass-by-copy (unusual for C structs, but
convenient they're basically u64) and all possibly problematic
operations return WARN_UNUSED_RESULT bool to make you handle the
over/underflow cases.
The new #include in json.h means we bolt11.c sees the amount.h definition
of MSAT_PER_BTC, so delete its local version.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Otherwise recent additional checks in tal() complain that we're freeing a
take() pointer. In this case, we're exiting so it's harmless, but it's
still a latent bug.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This existed previously, but code perturbations seem to have revealed it
now: test_bad_opening reports a leak.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is prep work for when we sign htlc txs with
SIGHASH_SINGLE|SIGHASH_ANYONECANPAY.
We still deal with raw signatures for the htlc txs at the moment, since
we send them like that across the wire, and changing that was simply too
painful (for the moment?).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is a bit different from the other cases: we need to iterate through
the peers and ask all the ones in openingd.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This avoids some very ugly switch() statements which mixed the two,
but we also take the chance to rename 'towire_gossip_' to
'towire_gossipd_' for those inter-daemon messages; they're messages to
gossipd, not gossip messages.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
That matches the other CSV names (HSM was the first, so it was written
before the pattern emerged).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
- reduces probability for a deadlock where we block on sending data because
the other peer cannot receive because it blocks on sending data etc.
- when either side sends so much data that it fills up the kernel/network buffer
- however sending out gossip can still block when (malicious) peer never receives
@renepickhardt: why is it actually lightningd.c with a d but hsm.c without d ?
And delete unused gossipd/gossip.h.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
In particular, all opening_read_peer_msg() callers need to know there
was an error (presumably, negotiating) so they can stop, but we should
not exit.
This lets us reenable the final disabled test.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We don't want to exit just because channel parameter negotiation
failed, but we do want to tell the master if it was a channel we were
trying to fund.
Note that lightningd still needs to fail the funding cmd if it gets a
fromwire_opening_fundee (they raced us and won), or an outright
failure.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Previously master would fail once the channel has been negotiated,
which is terrible, since the funder will have already broadcast tx.
Now we tell them if we have an active channel, and update if it goes away.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Prior to this, lightningd would hand uninteresting peers back to connectd,
which would then return it to lightningd if it sent a non-gossip msg,
or if lightningd asked it to release the peer.
Now connectd hands the peer to lightningd once we've done the init
handshake, which hands it off to openingd.
This is a deep structural change, so we do the minimum here and cleanup
in the following patches.
Lightningd:
1. Remove peer_nongossip handling from connect_control and peer_control.
2. Remove list of outstanding fundchannel command; it was only needed to
find the race between us asking connectd to release the peer and it
reconnecting.
3. We can no longer tell if the remote end has started trying to fund a
channel (until it has succeeded): it's very transitory anyway so not
worth fixing.
4. We now always have a struct peer, and allocate an uncommitted_channel
for it, though it may never be used if neither end funds a channel.
5. We start funding on messages for openingd: we can get a funder_reply
or a fundee, or an error in response to our request to fund a channel.
so we handle all of them.
6. A new peer_start_openingd() is called after connectd hands us a peer.
7. json_fund_channel just looks through local peers; there are none
hidden in connectd any more.
8. We sometimes start a new openingd just to send an error message.
Openingd:
1. We always have information we need to accept them funding a channel (in
the init message).
2. We have to listen for three fds: peer, gossip and master, so we opencode
the poll.
3. We have an explicit message to start trying to fund a channel.
4. We can be told to send a message in our init message.
Testing:
1. We don't handle some things gracefully yet, so two tests are disabled.
2. 'hand_back_peer .*: now local again' from connectd is no longer a message,
openingd says 'Handed peer, entering loop' once its managing it.
3. peer['state'] used to be set to 'GOSSIPING' (otherwise this field doesn't
exist; 'state' is now per-channel. It doesn't exist at all now.
4. Some tests now need to turn on IO logging in openingd, not connectd.
5. There's a gap between connecting on one node and having connectd on
the peer hand over the connection to openingd. Our tests sometimes
checked getpeers() on the peer, and didn't see anything, so line_graph
needed updating.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
openingd calculates our reserve based on the channel amount (even if
we're funding, to keep the calculation in one place), but it wasn't
reporting it back to the master daemon. We initialized it to 0 so that
valgrind wouldn't get upset, as it's part of a structure we send over
the wire.
Have openingd report back, and also initialize it to an impossible value
as extra assurance. And remove a stray (harmless but weird) semicolon.
Reported-by: Gálli Zoltán
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Also means we simplify the handle_gossip_msg() since everyone wants it to
use sync_crypto_write().
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We use 'our_commit' for the commit we sign (ie. the remote commitment tx),
and vice versa. Use local/remote nomenclature.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
structeq() is too dangerous: if a structure has padding, it can fail
silently.
The new ccan/structeq instead provides a macro to define foo_eq(),
which does the right thing in case of padding (which none of our
structures currently have anyway).
Upgrade ccan, and use it everywhere. Except run-peer-wire.c, which
is only testing code and can use raw memcmp(): valgrind will tell us
if padding exists.
Interestingly, we still declared short_channel_id_eq, even though
we didn't define it any more!
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
