Re: [bitcoin-dev] Safer sighashes and more granular SIGHASH_NOINPUT

2018-12-21 Thread Johnson Lau via bitcoin-dev
> On 21 Dec 2018, at 7:17 AM, Rusty Russell wrote: > > Johnson Lau writes: > >>> But I don't see how OP_CODESEPARATOR changes anything here, wrt NOINPUT? >>> Remember, anyone can create an output which can be spent by any NOINPUT, >>> whether we go for OP_MASK or simply not commiting to the i

Re: [bitcoin-dev] Safer NOINPUT with output tagging

2018-12-21 Thread Johnson Lau via bitcoin-dev
> On 21 Dec 2018, at 7:15 PM, Christian Decker > wrote: > > Johnson Lau writes: > >> I think the use of OP_CSV (BIP112) is not needed here (although it >> doesn’t really harm except taking a few more bytes). All you need is >> to sign the settlement tx with a BIP68 relative locktime. Since t

Re: [bitcoin-dev] Safer NOINPUT with output tagging

2018-12-21 Thread Johnson Lau via bitcoin-dev
> On 21 Dec 2018, at 7:40 PM, ZmnSCPxj wrote: > > Good morning Johnson, > >> The proposed solution is that an output must be “tagged” for it to be >> spendable with NOINPUT, and the “tag” must be made explicitly by the payer. >> There are 2 possible ways to do the tagging: > > First off, th

Re: [bitcoin-dev] Safer NOINPUT with output tagging

2018-12-21 Thread ZmnSCPxj via bitcoin-dev
Good morning Johnson, > The proposed solution is that an output must be “tagged” for it to be > spendable with NOINPUT, and the “tag” must be made explicitly by the payer. > There are 2 possible ways to do the tagging: First off, this is a very good idea I think. > While this seems fully

Re: [bitcoin-dev] Safer NOINPUT with output tagging

2018-12-21 Thread Christian Decker via bitcoin-dev
Johnson Lau writes: >> If we are using a trigger transaction the output of the setup >> transaction would simply be `2 Au Bu 2 OP_CMS`. If we were to use a CLTV >> in there we would not have an option to later attach a collaborative >> close transaction that is valid immediately. Furthermore the t