[bayasdev]

From another review of 1.0.3.

• reseal hands the sealer copies of the opened value and of the context and compares the result with its own, so a sealer that changes what it is given can't pass the check.
• A sealed value's two fields are read once and used as read.
• A ciphertext shorter than 81 bytes, the shortest box there is, is refused as malformed by open, encode and decode.
• A shared secret of all zeros is refused here too, not only in noble, with a test for a low-order one-time key.
• The README says a sealer of your own sees every value reseal moves, and names the one exception to old values opening: what 1.0.0 sealed on a big-endian machine.

The format doesn't change.