Often we only need a single secret, so it's clearer to have routines
to do just that. When we change to the lnd key scheme, there will be
no benefit in calculating them all together.
This also adds a test!
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Well, it's generated by shachain, so technically it is a sha256, but
that's an internal detail. It's a secret.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This means we'll find anywhere still using the payment key,
even though we still expose the private payment key to channeld.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
To avoid everything pulling in HTLCs stuff to the opening daemon, we
split the channel and commit_tx routines into initial_channel and
initial_commit_tx (no HTLC support) and move full HTLC supporting versions
into channeld.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
