On Wed, Sep 25, 2019 at 01:30:39PM +0000, ZmnSCPxj wrote: > > Since it's off chain, you could also provide R and C and a zero knowledge > > proof that you know an r such that: > > R = SHA256( r ) > > C = SHA256( x || r )
> > in which case you could do it with lightning as it exists today. > I can insist on paying only if the server reveals an `r` that matches some > known `R` such that `R = SHA256(r)`, as currently in Lightning network. > However, how would I prove, knowing only `R` and `x`, and that there exists > some `r` such that `R = SHA256(r)`, that `C = SHA256(x || r)`? If you know x and r, you can generate C and R and a zero knowledge proof of the relationship between x,C,R that doesn't reveal r (eg, I think you could do that with bulletproofs). Unfortunately that zkp already proves that C was generated based on x, so you get your timestamp for free. Ooops. :( Cheers, aj _______________________________________________ Lightning-dev mailing list Lightning-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/lightning-dev