Otherwise libwally pushes the psbt-key for 'witness script' onto the
serialized version and we fail the 'is this identical' check.
Relevant line from libwally, where if bytes, we push a psbt_key.
```
static void push_typed_varbuff(unsigned char **cursor, size_t *max,
uint64_t type,
const unsigned char *bytes, size_t bytes_len)
{
if (bytes) {
push_psbt_key(cursor, max, type, NULL, 0);
push_varbuff(cursor, max, bytes, bytes_len);
}
}
```
Reported-By: @grubles
Changelog-Fixed: openchannel_signed would fail on PSBT comparison of materially identical PSBTs
we only want to sign the inputs that we've reserved via utxopsbt or
fundpsbt. we mark them with a flag (reusing the now defunct max-len
flag is fine), then look for inputs with that flag to pass to signonly
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.
We force use of tal_wally_start/tal_wally_end around every wally
allocation, and with "end" make the caller choose where to reparent
everything.
This is particularly powerful where we allocate a tx or a psbt: we
want that tx or psbt to be the parent of the other allocations, so
this way we can reparent the tx or psbt, then reparent everything
else onto it.
Implementing psbt_finalize (which uses a behavior flag antipattern)
was tricky, so I ended up splitting that into 'psbt_finalize' and
'psbt_final_tx', which I think also makes the callers clearer.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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
Our psbt input/output comparison functions use serialization to compare
the things, but if there's a map with things in it and the map isn't
sorted exactly the same, it's highly likely you'll mark an identical inputs
as different.
To fix this, we sort all the input/output maps before linearizing them.
There's no stable ordering on unknown serialization, so linearizing
identical but mis-ordered unknown data will lead to 'wrong' results.
Instead, we just ignore any data that's in the psbt unknown struct.
There's probably also problems here with other PSBT maps. Really, this
needs a finer grained comparison function .... fuck
includes facilities for
- sorting psbt inputs by serial_id
- sorting psbt outputs by serial_id
- adding a serial_id
- getting a serial_id
- finding the diffset between two psbts
- adding a max_len to a psbt input
- getting a max_len from a psbt input
