Otherwise, they're malleable. We only care about our own anchor:
their anchor is their problem (and they'll probably get away with it).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is an address that bitcoind will happily pay to, but we know it's
a witness output so our inputs to the anchor are immalleable.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
You need to be running a bitcoind modified with segregated witness:
https://github.com/sipa/bitcoin/tree/segwit4
It needs 432 blocks to activate it!
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We want this because P2SH is something we can tell bitcoind to pay to;
we can't (yet?) do that with "raw" P2WPKH.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We currently linearize and then measure the string; this is better since
we're about to do it in a second place.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This can be used for proper support for fee negotiation; for the moment
it will be used for our anchor transaction creation.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We need to control the *inputs* to the anchor tx, to make sure they
pay to witness scripts (thus the anchor is immalleable). The easiest
way to do this is to hand out P2SH addresses for the user, and have
them pay into those. Then they hand us that tx and we use it to
create the anchor.
This is not a long-term solution!
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
sign_tx_input() now takes a witness_script arg: P2WPKH doesn't really
have a witness_script, but for signing it behaves as if it does.
This helper constructs that "fake" witness_script.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We need this for signing segwitness txs. Unfortunately, we don't have it
for transactions we received as hex, only ones we created; to make this safe
we use a pointer which is NULL if we don't know, and those will crash if
we try to sign or check their sigs.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This could only happen via our RPC interface (bitcoind should not give
us bad txs!) but it's better to be robust.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We got the -> second translation wrong by a factor of 512, and also we
need to move the median time in our tests otherwise bitcoind won't let
us spend the tx.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Without Alpha, it's superfluous. We're about to add segwit support,
but linearization requires a more powerful approach, and segwit
signature checking is completely different and really deserves its
own function.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I had already disabled it, and this clears the decks for Segregated Witness
which gives us everything we want.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We always set *matches to false (outside the branch, oops). We also
distinguish the case where we ack from the case where they acked,
which removes a FIXME and makes it work.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We now keep a list of commitment transaction states for "us" and
"them", as well as a "struct channel_state" for staged changes.
We manipulate these structures as we send out packets, receive
packets, or receive acknowledgement of packets. In particular, we
update the other nodes' staging_cstate as we send out our requests,
and update our own staging_cstate are we receive acks. When we
receive a request, we update both (as we immediately send out our
ack).
The RPC output is changed; rather than expose the complexity, we
expose our last committed state: what would happen if we have to drop
to the blockchain now.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
BOLT#2 says we MUST NOT send out commit messages with no changes (and
we drop the connection if the peer does). But that's harder than it
sounds: we can have changes in theory which cancel out (eg. fee
adjustments, not yet implemented) or others which don't change the
commit tx (eg. dust outputs). Simplest is to have a generation count,
which also allows us to simply show number of pending changes in RPC.
It's 32 bit, but you can only use it to screw yourself really (each
side can only add 1500 htlcs, so the rest would have to be fee
changes; wrapping will only make us hang up on you).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rather than creating packets then queueing them, call out to functions
which do both. This moves us towards doing more work in those functions
where we send out a request, which is sometimes clearer.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
And divide fees as specified there.
We still use fixed values rather than floating, and we don't send or
handle update_fee messages.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We used to have a hacky close timeout which would immediately fire
when we'd closed because the connection was down. Far better to have
a specific "connection lost" input, and have it respond like CMD_CLOSE.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We don't actually implement closing when we have HTLCs (we should
allow it, as that's what the clearing phase is for), since soon we'll
rewrite HTLC to match the async HTLC protocol of BOLT #2.
Note that this folds the close paths, using a simple check if we have
a close transaction. That's a slight state layer violation, but
reduces code duplication.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
For the change to asynchronous updates as specified by BOLT #2, we
need to know when the other side acknowledged a packet. This creates
a simple callback mechanism for it.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This uses libsodium (we could use openssl, but the required primitives
are only in 1.1.0 which is still in alpha).
It doesn't handle reconnections yet, either.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rusty Russell
philsong
zhibiao.pan