MerkleDrop v1

A Merkle root gates an airdrop that pays real ugnot. Successor to v0, which moved no coins and whose proof scheme was safe only by accident of encoding lengths.

Drop

How it differs from v0

1. Domain separated leaves. v0 hashed leaves bare and combined nodes commutatively, so an inner-node hash was also a valid leaf hash. It was not exploitable, but only because a v0 leaf preimage tops out at 61 bytes while an inner preimage is always 64. v1 tags leaves 0x00 and inner nodes 0x01.
2. Proofs bound to a position. v0 folded a sibling list of any length. v1 carries index and total, rebuilds the tree shape, and caps the depth.
3. A settable root and a closing height. v0's root was a const.
4. Real coins. v0 kept a uint64 ledger and moved nothing.

Leaf encoding

Reproduce this off chain to rebuild the tree:

leaf = "gno.land/r/moul/x/daily/merkledrop/v1|<index>|<address>|<amount>"
tree = Tendermint simple tree, leaf 0x00, inner 0x01

Example allocations

Seeded at deploy so the drop can be exercised without a generator. A live drop commits only a root and stores none of this.