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>
This requires us to call ecdh() in the corner case where the blinding seed
is in the TLV itself (which is the case for the start of a blinded route).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This happened on my testnet node because I've been failing to reconnect to
a node which created a channel and never exchanged announcement sigs.
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>
For messages, we use the onion but payload lengths 0 and 1 aren't special.
Create a flag to disable that logic.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Even without optimization, it's faster to walk all the channels than
ping another daemon and wait for the response.
Changelog-Changed: Forwarding messages is now much faster (less inter-daemon traffic)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Instead of saving a stripped_update, we use the new
local_fail_in_htlc_needs_update.
One minor change: we return the more correct
towire_temporary_channel_failure when the node is still syncing.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The idea is that gossipd can give us the cupdate we need for an error, and
we wire things up so that we ask for it (async) just before we send the
error to the subdaemon.
I tried many other things, but they were all too high-risk.
1. We need to ask gossipd every time, since it produces these lazily
(in particular, it doesn't actually generate an offline update unless
the channel is used).
2. We can't do async calls in random places, since we'll end up with
an HTLC in limbo. What if another path tries to fail it at the same time?
3. This allows us to use a temporary_node_failure error, and upgrade it
when gossipd replies. This doesn't change any existing assumptions.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is a common thing to do, so create a macro.
Unfortunately, it still needs the type arg, because the paramter may
be const, and the return cannot be, and C doesn't have a general
"(-const)" cast.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This completes the conversion; any in-flight HTLC failures get turned into temporary_node_failures.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This cleans up the "local failure" callers for incoming HTLCs to hand
an onionreply instead of making us generate it from the code inside
make_failmsg.
(The db path still needs make_failmsg, so that's next).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-deprecated: Plugins: htlc_accepted_hook "failure_code" only handles simple cases now, use "failure_message".
Unfortunately the invoice_payment_hook can give us a failcode, so I simply
restrict it to the two sensible ones.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-deprecated: plugins: invoice_payment_hook "failure_code" only handles simple cases now, use "failure_message".
We tell channeld that an htlc is bad by sending it a 'struct
failed_htlc'. This usually contains an onionreply to forward, but for
the case where the onion itself was bad, it contains a failure code
instead.
This makes the "send a failed_htlc for a bad onion" a completely
separate code path, then we can work on removing failcodes from the
other path.
In several places 'failcode' is now changed to 'badonion' to reflect
that it can only be a BADONION failcode.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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're going to change our internal structure next, so this is preparation.
We populate existing errors with temporary node failures, for simplicity.
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>
I hadn't realized that lightningd asks gossipd every time we forward
a payment. But I'm going to abuse it here to get the latest channel_update,
otherwise (as lightningd takes over error message generation) lightningd
needs to do an async request at various painful points.
So have gossipd tell us the lastest update (stripped so compatible with
the strange in-onion-error format).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Turn it into temporary node failure: this only happens if we restart
with a failed htlc in, but it's clearer and more robust to handle it
generically.
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>
1. forward_htlc sets hout to NULL.
2. forward_htlc passes &hout to send_htlc_out.
3. forward_htlc checks the failcode and frees(NULL) and sets hout to NULL
(again). This in fact covers every failcode which send_htlc_out returns.
We should ensure send_htlc_out sets *houtp to NULL on failure; in fact,
both callers pass houtp, so we can make it unconditional.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If the peer is not connected, or other error which means we don't
actually create an outgoing HTLC, we don't record the
short_channel_id. This is unhelpful!
Pass the scid down to the wallet code, and explicitly hand the
scid and amount down to the notification code rather than handing it
the htlc_out (which it doesn't need).
Changelog-Changed: JSON API: `listforwards` now shows `out_channel` even if we couldn't forward.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Make the `htlc_accepted` hook the first chained hook in our repertoire. The
plugins are called one after the other in order until we have no more plugins
or the HTLC was handled by one of the plugins. If no plugins handles the HTLC
we continue to handle it internally like always.
Handling in this case means the plugin returns either `{"result": "resolve",
...}` or `{"result": "fail", ...}`.
Changelog-Changed: plugin: Multiple plugins can now register for the htlc_accepted hook.
The newly introduced type is used to determine what the call semantics of the
hook are. We have `single` corresponding to the old behavior, as well as
`chain` which allows multiple plugins to register for the hook, and they are
then called sequentially (if all plugins return `{"result": "continue"}`) or
exit the chain if the hook event was handled.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Removed: Relative plugin paths are not relative to startup (deprecated v0.7.2.1)
Changelog-Removed: Dummy fields in listforwards (deprecated v0.7.2.1)
This shouldn't happen if channeld is working properly, but I'm going to
change that, and this current code means we stop responding at that point
(not every failpath in peer_accepted_htlc() called channel_internal_error).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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>
`wallet_payment_store` would free the `wallet_payment` instance which would
then cause us to reload it from the DB. Instead of doing the store->free->load
dance we now tell `wallet_payment_store` whether it should take ownership and
leave it alone if not.
Passing the payment around instead of referencing it through payment_hash and
partid is a nice side-effect.
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>
The invoice_try_pay code now takes a set, rather than a single htlc, but
it's basically the same thing.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is a transient field, so rework things so we don't leave it in
struct htlc_out. Instead, load htlc_in first and connect htlc_out to
them as we go.
This also changes one place where we use it instead of the am_origin
flag.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is in preparation for partial payments. For existing payments,
partid is 0 (to match the corresponding payment).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is in preparation for partial payments. For existing payments,
partid is 0 (arbitrarity) and total_msat is msatoshi.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Because my node runs under valgrind, it can take quite a while to
sync; nodes tend to disconnect and reconnect if you block too long.
This is particularly problematic since we often update fees: when the
other side sends its commitment_signed we block.
In particular, this triggers the corner case we have where we
update_fee twice, disconnecting each time, and our state machine gets
confused (which is why we never saw this exact corner case before this
change in 0.7.3!).
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>
Rusty Russell
Christian Decker
Michael Schmoock
Vasil Dimov