This is also required for actually creating usable onions. For the moment,
due to API limitations, we only let them set realm 0.
Note that the privkey parsing was broken, requiring an additional two
hex digits, overflowing the buffer, and were ignored.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Add odd-length string can never be valid hex!
In addition, don't try to print the next hop if there isn't one, but
always print the (raw) payload.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We need to do it in various places, but we shouldn't do it lightly:
the primitives are there to help us get overflow handling correct.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
As a side-effect of using amount_msat in gossipd/routing.c, we explicitly
handle overflows and don't need to pre-prune ridiculous-fee channels.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
