Good morning Christopher, > >> But more importantly, adding limitations on OP_RETURN transactions is not > >> helpful. Users who want to embed arbitrary data in their transactions can > >> always do so by encoding their data inside the values of legacy > >> multi-signature scriptpubkeys (pubkeys can be generated without knowing > >> the private key in order to encode non-key related data). Not only can > >> users do this, users have done this in the past. However, this behaviour > >> is problematic because such multi-signature "data" scriptpubkeys are > >> indistinguishable from "real" multisignature scriptpubkeys, and thus must > >> be kept in the UTXO set. This differs from outputs using OP_RETURN which > >> are provably unspendable, and therefore can be safely omitted from the > >> UTXO set. > > This sounds like a good justification to remove the legacy multi-signature > capabilities as well.
The same technique can be used on P2PKH as well --- the "pubkey hash" need not be a hash of a public key, it can be a 20-byte commitment, or even an ASCII message like "ZmnSCPxj is the best" (20 characters, I counted). There is nothing that *can* check if the hash of a public key is indeed the hash of a public key unless you actually reveal the public key. If you need a 32-byte commitment, a P2WSH would work --- again the "script hash" need not be a hash of a script, it can be any 32-byte commitment. In all these cases you have to waste 547 satoshi, but that tends to be small compared to tx fees currently. Regards, ZmnSCPxj _______________________________________________ bitcoin-dev mailing list bitcoin-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
