add OP_DATASIGVERIFY

[gandrewstone]

OP_DATASIGVERIFY allows signed data to be imported into a script. This data can then have many uses, depending on the rest of the script, such as deciding spendability of several possible addresses. This opcode therefore enables the powerful blockchain concept of an "oracle" -- an entity that publishes authoritative statements about extra-blockchain events -- to be used in the Bitcoin Cash blockchain. For an example use of how this opcode can be used to enable binary contracts on any security or betting on any quantitatively decidable event (such as a sports match) please click here. But this is just one example; as the Bitcoin Cash Script language grows in expressiveness, it is anticipated that this opcode will be used in many other applications.

[dexX7]

I really like this proposal, though I'm wondering about the following:

1. All other CHECKSIG opcodes use public keys instead of addresses. What's the rationale behind using the hash160 instead of a pubkey?

2. And why prepending data with "Bitcoin Signed Message:\n"?

3. Also I'm wondering, whether it could make more sense to simply check the signature for the data provided, without hashing the data first. If anyone wants to sign a hash, he or she could just do so and provide a hash instead of the data. With (2) this would allow to spend coins based on the status of other transactions, even without direct link by reusing the signature of that transaction.

[shadders]

Probably obfuscation until spend time similar to p2pkh. Along with saving some bytes. Would like to see a distinction madr in the spec between an address and a pk hash though. Address has a version byte. Pk hash doesn't.

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On Feb 21, 2018 5:40 PM, "dexX7" ***@***.***> wrote: I really like this proposal, though I'm wondering about the following: All other CHECKSIG opcodes use public keys instead of addresses. What's the rationale behind using the hash160 instead of a pubkey? — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#6 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AA52iNtmQzbE8s6QR4GWNlkccdQq9cyGks5tW8hZgaJpZM4SC7w5> .