1. Remove the very concept of ONION_REPLY_SIZE, instead make it a
local variable in create_onionreply().
2. Use the proper fromwire_ primitives in unwrap_onionreply() so we
don't have to do explicit length checks.
3. Make fromwire_tal_arrn() return NULL if it fails to pull, instead of
a zero-length allocation.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Fixed: Protocol: we now correctly decrypt non-256-length onion errors (we always forwarded them fine, now we actually can parse them).
a4c482dc07