You can use rs->nextcase, but we don't always keep that around, so
keep a flag in onion_payload.
We'll use this in the "do we need to return a blinded error code"
patch.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
And check it in invoice.c, insead of a hack where we compare against invhash.
Restore checking, too.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We actually want lightningd to create these, since it wants to put the
path_id secret in the last element. So best API is actually a generic
one, rather than separate APIs to create first and last ones.
And really, the more explicit initialization makes the users clearer.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
