Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-28 Thread Oleg Andreev
> On 27 Apr 2015, at 21:21, Peter Todd wrote: > > Even right now there are edge cases without > good solutions, like how in a multisig environment any of the key > holders can mutate transactions. Can't we add requirement for RFC6979 signatures to mitigate this? Of course, multiple signers ca

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-27 Thread Peter Todd
On Sat, Apr 25, 2015 at 10:32:36AM -0400, Stephen Morse wrote: > Hi William, > > I personally prefer this solution, since it nails the problem > > completely with one simple and obvious change. The BIP 62 approach is > > more like a game of wac-a-mole. > > > > The two are complementary, not compe

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-26 Thread Joseph Poon
On Sat, Apr 25, 2015 at 11:51:37PM -0700, Joseph Poon wrote: > signs the sigScript of the redeemed output. Err, typo, I meant: ... signs the *scriptPubKey* of the redeemed output. -- Joseph Poon -- One dashboard for ser

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-26 Thread Joseph Poon
On Sun, Apr 26, 2015 at 03:01:10AM +0300, s7r wrote: > It's true that malleability is not the end of the world, but it is > annoying for contracts and micropayment channels, especially refunds > spending the fund tx before it is even in the blockchain, relying > solely on its txid. Agreed, needing

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-25 Thread s7r
Thank you all for your comments. The youtube video was indeed very educative and nice to watch. It's true that malleability is not the end of the world, but it is annoying for contracts and micropayment channels, especially refunds spending the fund tx before it is even in the blockchain, relying

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-25 Thread Stephen Morse
Hi Gregory, In particular not covering the ID allows for transaction replay which > can result in monetary losses far more severe than any possible > mishandling of malleability could result in. Byzantine attackers can > costlessly replay your old transactions any time anyone reuses an > address,

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-25 Thread Stephen Morse
Hi William, I personally prefer this solution, since it nails the problem > completely with one simple and obvious change. The BIP 62 approach is > more like a game of wac-a-mole. > The two are complementary, not competing. BIP62 prevents *non-signers* from mutating the transactions, which is ver

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-24 Thread Gregory Maxwell
On Fri, Apr 24, 2015 at 7:58 PM, William Swanson wrote: > On Thu, Apr 16, 2015 at 9:12 AM, s7r wrote: >> Thanks for your reply. I agree. Allen has a good point in the previous >> email too, so the suggestion might not fix anything and complicate things. > > The BIP 62 approach to malleability isn

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-24 Thread William Swanson
On Thu, Apr 16, 2015 at 9:12 AM, s7r wrote: > Thanks for your reply. I agree. Allen has a good point in the previous > email too, so the suggestion might not fix anything and complicate things. The BIP 62 approach to malleability isn't the only option. Another approach is to sign the transaction

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-24 Thread Jorge Timón
s7r you may be interested in this video explaining several aspects of malleability: https://www.youtube.com/watch?v=jyDE-aFqJTs It is pre BIP62, but I believe it is very relevant and will hopefully clear some of your doubts. The signer of TX1 will always be able to change the signature and thus the

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-24 Thread Jorge Timón
Oh, no, sorry, it also covers bip62. On Fri, Apr 24, 2015 at 10:55 AM, Jorge Timón wrote: > s7r you may be interested in this video explaining several aspects of > malleability: https://www.youtube.com/watch?v=jyDE-aFqJTs > It is pre BIP62, but I believe it is very relevant and will hopefully > c

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-18 Thread s7r
Understood. That is unfortunate, but not the end of the world. If you could please give feedback also to these last comments / questions: How far are we at this moment from BIP62? Can an user send a non-malleable tx now, if enforces some additional rules? As for the security of the system, it doe

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-17 Thread Pieter Wuille
> Anyone can alter the txid - more details needed. The number of altered > txids in practice is not so high in order to make us believe anyone can > do it easily. It is obvious that all current bitcoin transactions are > malleable, but not by anyone and not that easy. At least I like to think so.

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-16 Thread s7r
On 4/16/2015 8:34 PM, Mark Friedenbach wrote: > At this moment anyone can alter the txid. Assume transactions are 100% > malleable. > Anyone can alter the txid - more details needed. The number of altered txids in practice is not so high in order to make us believe anyone can do it easily. It i

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-16 Thread Mark Friedenbach
At this moment anyone can alter the txid. Assume transactions are 100% malleable. On Apr 16, 2015 9:13 AM, "s7r" wrote: > Hi Pieter, > > Thanks for your reply. I agree. Allen has a good point in the previous > email too, so the suggestion might not fix anything and complicate things. > > The prob

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-16 Thread s7r
Hi Pieter, Thanks for your reply. I agree. Allen has a good point in the previous email too, so the suggestion might not fix anything and complicate things. The problem I am trying to solve is making all transactions non-malleable by default. I guess there is a very good reason why BIP62 will not

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-15 Thread Pieter Wuille
On Apr 16, 2015 1:46 AM, "s7r" wrote: > but for transaction versions? In simple terms, if > 75% from all the > transactions in the latest 1000 blocks are version 'n', mark all > previous transaction versions as non-standard and if > 95% from all the > transactions in the latest 1000 blocks are ver

Re: [Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-15 Thread Allen Piscitello
If I had a time locked signed transaction where I threw away the key, this would potentially invalidate my transaction. What is the point of such a rule? On Wed, Apr 15, 2015 at 6:43 PM, s7r wrote: > Hi, > > Would it be wise to add a consensus rule like the one we have for blocks, > > (if > 75%

[Bitcoin-development] 75%/95% threshold for transaction versions

2015-04-15 Thread s7r
Hi, Would it be wise to add a consensus rule like the one we have for blocks, (if > 75% from last 1000 blocks are version 'n' mark version 'n' as standard for blocks and if > 95% from the last 1000 blocks are version 'n' mark previous block versions as invalid) but for transaction versions? In s