- see comment in lnaddr.py
- Previously we used feature bit 50/51 for trampoline.
The spec subsequently defined fbit 50/51 as option_zeroconf, which
requires fbit 46/47 (option_scid_alias) to also be set.
We moved the non-standard trampoline fbit to a different int.
However, old wallets might have old invoices saved that set fbit 50/51
for trampoline, and those would not have the dependent bit set.
Invoices are parsed at wallet-open, so if the parser ran these checks,
those wallets could not be opened.
- note: we could potentially also run lnaddr.validate_and_compare_features
when saving new invoices into the wallet but this is not done here
Somewhat a follow-up to 649ce979ab.
This adds some safety belts so we don't accidentally sign a tx that
contains a dummy address.
Specifically we check that tx does not contain output for dummy addr:
- in wallet.sign_transaction
- in network.broadcast_transaction
The second one is perhaps redundant, but I think it does not hurt.
- when creating an invoice, if we had multiple chans with the same trampoline,
were putting duplicate t-hints into the invoice
- when paying an invoice that had duplicate t-hints, we would sometimes
construct invalid paths (SRC>T1->T1->DST)
eclair sends CHANNEL_DISABLED if its peer is offline. E.g. we might be
trying to pay a mobile phone with the app closed. In that case we
should not cache the CHANNEL_DISABLED for too long.
- rename trampoline_forwardings -> final_onion_forwardings,
because this dict is used for both trampoline and hold invoices
- remove timeout from hold_invoice_callbacks (redundant with invoice)
- add test_failure boolean parameter to TestPeer._test_simple_payment,
in order to test correct propagation of OnionRoutingFailures.
- maybe_fulfill_htlc: raise an OnionRoutingFailure if we do not have
the preimage for a payment that does not have a hold invoice callback.
Without this, the above unit tests stall when we use test_failure=True
- introduce SentHtlcInfo named tuple
- some previously unnamed tuples are now much shorter:
create_routes_for_payment no longer returns an 8-tuple!
- sent_htlcs_q (renamed from sent_htlcs), is now keyed on payment_hash+payment_secret
(needed for proper trampoline forwarding)
- add RecvMPPResolution enum for possible states of a pending incoming MPP,
and use it in check_mpp_status
- new state: "FAILED", to allow nicely failing back the whole MPP set
- key more things with payment_hash+payment_secret, for consistency
(just payment_hash is insufficient for trampoline forwarding)
- maybe_fulfill_htlc returns a forwarding callback that
covers both cases.
- previously, the callback of hold invoices was called as a
side-effect of lnworker.check_mpp_status.
- the same data structures (lnworker.trampoline_forwardings,
lnworker.trampoline_forwarding_errors) are used for both
trampoline forwardings and hold invoices.
- maybe_fulfill_htlc still recursively calls itself to perform
checks on trampoline onion. This is ugly, but ugliness is now
contained to that method.
- fix parameters passed to maybe_forward_trampoline
- use lnworker.trampoline_forwardings as a semaphore for ongoing
trampoline payments
- if a trampoline payment fails, fail all received HTLCs
scenario:
- user opens a lightning channel and exports an "imported channel backup"
- user closes channel via local-force-close
- local ctx is published, to_local output has user's funds and they are CSV-locked for days
- user restores wallet file from seed and imports channel backup
- new wallet file should be able to sweep coins from to_local output (after CSV expires)
This was not working previously, as the local_payment_basepoint was not included in the
imported channel backups, and the code was interpreting the lack of this as the channel not
having option_static_remotekey enabled. This resulted in lnutil.extract_ctn_from_tx
using an incorrect funder_payment_basepoint, and lnsweep not recognising the ctx due to
the garbage ctn value.
The imported channel backup serialisation format is slightly changed to include the
previously missing field, and its version number is bumped (0->1). We allow importing
both version 0 and version 1 backups, however v0 backups cannot handle the above
described scenario (they can only be used to request a remote-force-close).
Note that we were/are setting the missing local_payment_basepoint to the pubkey of
one of the wallet change addresses, which is bruteforceable if necessary, but I
think it is not worth the complexity to add this bruteforce logic. Also note
that the bruteforcing could only be done after the local-force-close was broadcast.
Ideally people with existing channels and already exported v0 backups should re-export
v1 backups... Not sure how to handle this.
closes https://github.com/spesmilo/electrum/issues/8516