<div dir="ltr"><div>I've joked that BIP62 is the "whack-a-mole" BIP in that it addresses many vectors for txid malleability, but maybe there are more. And more importantly, it addresses 3rd party malleability. It's not helpful in the context of lightning channel creation because ECDSA sigs are inherently malleable. You can always re-sign the same message with a different k-value and get a different signature.<br><br></div><div>The functionality that's needed is to be able to reliably spend from unconfirmed transactions. Segregated witness can accomplish that, but it quite a large hard-fork change. sighash_noinput can also accomplish that: as input txids are not signed, if they change, the spending transaction can be modified while leaving counterparty signatures intact.<br><br></div><div>I'm hoping to start a new "testnet-L" similar to testnet3, with this sighash type so that we can test malleability mitigation out.<br><br></div><div>(Oh also, hi mailing list, sorry I have not posted till now! But I will start posting!)<br></div><div><br></div><div>-Tadge<br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Nov 19, 2015 at 9:56 AM, Mark Friedenbach <span dir="ltr"><<a href="mailto:mark@friedenbach.org" target="_blank">mark@friedenbach.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">The basic idea of the soft-fork plan is very simple --- have the scriptPubKey be just the 20-byte hash of the redeem script. The scriptSig of the spending input is empty. The actual scriptSig, with the redeem script and signatures, is contained in a separate Merkle tree committed to elsewhere in the block (e.g. in the last output of the coinbase, or the last output of the last transaction).<br></div><div class="HOEnZb"><div class="h5"><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Nov 19, 2015 at 7:31 AM, Greg Sanders <span dir="ltr"><<a href="mailto:gsanders87@gmail.com" target="_blank">gsanders87@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">The hardfork variant is quite simple, if I understood it correctly. You just stick the signatures in another parallel merkle tree. So if you don't want to validate signatures, just don't download them, and validate everything else. TXIDs don't use the signature at all. Nothing to malleate, AFAIK. Not sure what the softfork plan is, but it will be a talk at Scaling Bitcoin HK.</div><div class="gmail_extra"><br><div class="gmail_quote"><div><div>On Thu, Nov 19, 2015 at 10:28 AM, Glenn Tarbox, PhD <span dir="ltr"><<a href="mailto:glenn@tarbox.org" target="_blank">glenn@tarbox.org</a>></span> wrote:<br></div></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div><div dir="ltr"><div class="gmail_extra"><span><br><div class="gmail_quote">On Thu, Nov 19, 2015 at 4:33 AM, <a href="mailto:sickpig@gmail.com" target="_blank">sickpig@gmail.com</a> <span dir="ltr"><<a href="mailto:sickpig@gmail.com" target="_blank">sickpig@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div>Hi Pierre <br><br></div>you could start here <span style="font-size:12px"><br><br><a href="https://github.com/ElementsProject/elementsproject.github.io#segregated-witness" rel="nofollow" target="_blank">https://github.com/ElementsProject/elementsproject.github.io#segregated-witness</a><br><a href="https://people.xiph.org/~greg/blockstream.gmaxwell.elements.talk.060815.pdf" target="_blank">https://people.xiph.org/~greg/blockstream.gmaxwell.elements.talk.060815.pdf</a><br><a href="https://github.com/ElementsProject/elements" target="_blank">https://github.com/ElementsProject/elements</a></span></blockquote></div><br></span>There was a brief blip on Reddit:</div><div class="gmail_extra"><br></div><div class="gmail_extra"><a href="https://www.reddit.com/r/Bitcoin/comments/3ngtx5/could_the_segregated_witness_part_of_the/cwnthlh" target="_blank">https://www.reddit.com/r/Bitcoin/comments/3ngtx5/could_the_segregated_witness_part_of_the/cwnthlh</a></div><div class="gmail_extra"><br></div><div class="gmail_extra">Its weird how little information there is on Segregated Witness. I'm guessing its a simple concept and those working on it (sipa / gmaxwell) haven't felt the need to write it up.</div><div class="gmail_extra"><br></div><div class="gmail_extra">That it "apparently" can be done with a soft fork similar to P2SH is good news... I guess...<span><font color="#888888"><br><br clear="all"><div><br></div>-- <br><div><div dir="ltr"><div><div dir="ltr"><div>Glenn H. Tarbox, PhD<br></div><div> =]|[=</div></div></div></div></div>
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