Re: [Bitcoin-development] 75%/95% threshold for transaction versions
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 touch v1 anyway. I am trying to build a bitcoin contract which will relay on 3 things: - coinjoin / txes with inputs from multiple users which are signed by all users after they are merged together (every user is sure his coins will not be spent without the other users to spend anything, as per agreed contract); - pre-signed txes with nLockTime 'n' weeks. These txes will be signed before the inputs being spent are broadcasted/confirmed, using the txid provided by the user before broadcasting it. Malleability hurts here. - P2SH In simple terms, how malleable transactions really are in the network at this moment? Who can alter a txid without invalidating the tx? Just the parties who sign it? The miners? Anyone in the network? This is a little bit unclear to me. Another thing I would like to confirm, the 3 pieces of the bitcoin protocol mentioned above will be supported in _any_ future transaction version or block version, regardless what changes are made or features added to bitcoin core? The contract needs to be built and left unchanged for a very very long period of time... On 4/16/2015 8:22 AM, Pieter Wuille wrote: On Apr 16, 2015 1:46 AM, s7r s...@sky-ip.org mailto:s...@sky-ip.org 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 version 'n' mark all previous transaction versions as invalid. What problem are you trying to solve? The reason why BIP62 (as specified, it is just a draft) does not make v1 transactions invalid is because it is opt-in. The creator of a transaction needs to agree to protect it from malleability, and this subjects him to extra rules in the creation. Forcing v3 transactions would require every piece of wallet software to be changed. -- Pieter -- BPM Camp - Free Virtual Workshop May 6th at 10am PDT/1PM EDT Develop your own process in accordance with the BPMN 2 standard Learn Process modeling best practices with Bonita BPM through live exercises http://www.bonitasoft.com/be-part-of-it/events/bpm-camp-virtual- event?utm_ source=Sourceforge_BPM_Camp_5_6_15utm_medium=emailutm_campaign=VA_SF ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] 75%/95% threshold for transaction versions
At this moment anyone can alter the txid. Assume transactions are 100% malleable. On Apr 16, 2015 9:13 AM, s7r s...@sky-ip.org 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 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 touch v1 anyway. I am trying to build a bitcoin contract which will relay on 3 things: - coinjoin / txes with inputs from multiple users which are signed by all users after they are merged together (every user is sure his coins will not be spent without the other users to spend anything, as per agreed contract); - pre-signed txes with nLockTime 'n' weeks. These txes will be signed before the inputs being spent are broadcasted/confirmed, using the txid provided by the user before broadcasting it. Malleability hurts here. - P2SH In simple terms, how malleable transactions really are in the network at this moment? Who can alter a txid without invalidating the tx? Just the parties who sign it? The miners? Anyone in the network? This is a little bit unclear to me. Another thing I would like to confirm, the 3 pieces of the bitcoin protocol mentioned above will be supported in _any_ future transaction version or block version, regardless what changes are made or features added to bitcoin core? The contract needs to be built and left unchanged for a very very long period of time... On 4/16/2015 8:22 AM, Pieter Wuille wrote: On Apr 16, 2015 1:46 AM, s7r s...@sky-ip.org mailto:s...@sky-ip.org 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 version 'n' mark all previous transaction versions as invalid. What problem are you trying to solve? The reason why BIP62 (as specified, it is just a draft) does not make v1 transactions invalid is because it is opt-in. The creator of a transaction needs to agree to protect it from malleability, and this subjects him to extra rules in the creation. Forcing v3 transactions would require every piece of wallet software to be changed. -- Pieter -- BPM Camp - Free Virtual Workshop May 6th at 10am PDT/1PM EDT Develop your own process in accordance with the BPMN 2 standard Learn Process modeling best practices with Bonita BPM through live exercises http://www.bonitasoft.com/be-part-of-it/events/bpm-camp-virtual- event?utm_ source=Sourceforge_BPM_Camp_5_6_15utm_medium=emailutm_campaign=VA_SF ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- BPM Camp - Free Virtual Workshop May 6th at 10am PDT/1PM EDT Develop your own process in accordance with the BPMN 2 standard Learn Process modeling best practices with Bonita BPM through live exercises http://www.bonitasoft.com/be-part-of-it/events/bpm-camp-virtual- event?utm_ source=Sourceforge_BPM_Camp_5_6_15utm_medium=emailutm_campaign=VA_SF___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] 75%/95% threshold for transaction versions
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 is obvious that all current bitcoin transactions are malleable, but not by anyone and not that easy. At least I like to think so. From your answer I understand that right now if I create a transaction (tx1) and broadcast it, you can alter its txid at your will, without any mining power and/or access to my private keys so I would end up not recognizing my own transaction and probably my change too (if my systems rely hardly on txid)? On Apr 16, 2015 9:13 AM, s7r s...@sky-ip.org mailto:s...@sky-ip.org 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 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 touch v1 anyway. I am trying to build a bitcoin contract which will relay on 3 things: - coinjoin / txes with inputs from multiple users which are signed by all users after they are merged together (every user is sure his coins will not be spent without the other users to spend anything, as per agreed contract); - pre-signed txes with nLockTime 'n' weeks. These txes will be signed before the inputs being spent are broadcasted/confirmed, using the txid provided by the user before broadcasting it. Malleability hurts here. - P2SH In simple terms, how malleable transactions really are in the network at this moment? Who can alter a txid without invalidating the tx? Just the parties who sign it? The miners? Anyone in the network? This is a little bit unclear to me. Another thing I would like to confirm, the 3 pieces of the bitcoin protocol mentioned above will be supported in _any_ future transaction version or block version, regardless what changes are made or features added to bitcoin core? The contract needs to be built and left unchanged for a very very long period of time... On 4/16/2015 8:22 AM, Pieter Wuille wrote: On Apr 16, 2015 1:46 AM, s7r s...@sky-ip.org mailto:s...@sky-ip.org mailto:s...@sky-ip.org mailto:s...@sky-ip.org 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 version 'n' mark all previous transaction versions as invalid. What problem are you trying to solve? The reason why BIP62 (as specified, it is just a draft) does not make v1 transactions invalid is because it is opt-in. The creator of a transaction needs to agree to protect it from malleability, and this subjects him to extra rules in the creation. Forcing v3 transactions would require every piece of wallet software to be changed. -- Pieter -- BPM Camp - Free Virtual Workshop May 6th at 10am PDT/1PM EDT Develop your own process in accordance with the BPMN 2 standard Learn Process modeling best practices with Bonita BPM through live exercises http://www.bonitasoft.com/be-part-of-it/events/bpm-camp-virtual- event?utm_ source=Sourceforge_BPM_Camp_5_6_15utm_medium=emailutm_campaign=VA_SF ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net mailto:Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- BPM Camp - Free Virtual Workshop May 6th at 10am PDT/1PM EDT Develop your own process in accordance with the BPMN 2 standard Learn Process modeling best practices with Bonita BPM through live exercises http://www.bonitasoft.com/be-part-of-it/events/bpm-camp-virtual- event?utm_ source=Sourceforge_BPM_Camp_5_6_15utm_medium=emailutm_campaign=VA_SF ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
