[coinb.in] Open Source, Multi Signature, HD Wallet, SegWit/Bech32 and more!

[OutCast3k]

@ktorn I've been looking into it, its a little trickier than I first thought but should have it resolved over the next couple of days.

No worries, take your time.

Fixed you can now send back to a multisig address.

One of my test cases http://blockchain.info/tx/832679f95685a8178bc7128dd3450fc29d0552a3ee6bcc3f1254f48d0ba4e0c4

[ktorn]

Fixed you can now send back to a multisig address.

I've tested and it works for me as well: https://blockchain.info/tx/13326d4e0aa8ed620d4d28d26810f4ac9ce75e508d84b218f281c681389abdbd

Great work OutCast3k! 

[fbueller]

This is an awesome project, very glad I saw this thread. I'm working on implementing multisig into Bitwasp, and currently support for multisig sucks in the clients. I was hoping someone would come up with a stateless signing tool. Looking forward to your marketplace, I haven't seen another open source one before

[RagnarDanneskjold]

This is an awesome project, very glad I saw this thread.

+1 million!

Great stuff outkast - i will use this EVERY day from now on

[fbueller]

Just ran through a test transaction, this works great! Kudos again. My shitty laptop apparently can't sign transactions, the script crashes, but I've tested it successfully on another machine, works a treat. 3cac39fc4aefc65aaa5419a60ab52aebc01d3c55f178a8ebe274650916cf38d6

[OutCast3k]

Just ran through a test transaction, this works great! Kudos again. My shitty laptop apparently can't sign transactions, the script crashes, but I've tested it successfully on another machine, works a treat. 3cac39fc4aefc65aaa5419a60ab52aebc01d3c55f178a8ebe274650916cf38d6

Good to hear it worked.

[vm_mpn]

I just have to say - It's amazing what you guys are doing...

Thank You!

[OutCast3k]

I just have to say - It's amazing what you guys are doing...

Thank You!

Thanks

This is an awesome project, very glad I saw this thread.

+1 million!

Great stuff outkast - i will use this EVERY day from now on

Thanks

[HostFat]

I would be cool if someone could make an easy android app to arrange and start a poker match.
So everyone will be able to play poker everywhere with just their smartphone and empty pockets

[em]

Maybe I'm missing something, but I think that with this method the Seller is at a disadvantage here, because the Buyer might renege on his promise and not sign the transaction after receiving the goods (e.g., unless the Seller ship an extra amount of goods). True, a mediator could break the tie if two signatures over three were sufficient to release the payment, but it would be much better if recourse to trusted third parties could be minimized.
A scheme that might work better would run as follows:

- After reaching a verbal agreement, Buyer issues a "Conditional payment" for Seller (which at this stage Buyer may cancel at any time)
- Seller accepts the payment by "posting a bond" of, say, X% of the amount.  The payment's status becomes "Committed", and Buyer can't cancel it anymore.
- Seller ships the goods
- Buyer receives the goods, and "releases the payment": the initial amount is paid to Seller, and at the same time the bond is paid back to Buyer.

Is it possible to implement this protocol with p2sh primitives?

[OutCast3k]

Maybe I'm missing something, but I think that with this method the Seller is at a disadvantage here, because the Buyer might renege on his promise and not sign the transaction after receiving the goods (e.g., unless the Seller ship an extra amount of goods). True, a mediator could break the tie if two signatures over three were sufficient to release the payment, but it would be much better if recourse to trusted third parties could be minimized.
A scheme that might work better would run as follows:

- After reaching a verbal agreement, Buyer issues a "Conditional payment" for Seller (which at this stage s/he may cancel at any time)
- Seller accepts the payment by "posting a bond" of, say, X% of the amount.  The payment's status becomes "Committed", and Buyer can't cancel it anymore.
- Seller ships the goods
- Buyer receives the goods, and "releases the payment": the initial amount is paid to Seller, and at the same time the bond is paid back to Buyer.

Is it possible to implement this protocol with p2sh primitives?

Hey,

Thanks for the feedback.

You've mentioned that the sellers maybe put at a disadvantage here because the buyer may not sign the transaction, well, there are many tried and tested sites where this type of system works. Such as; localbitcoins, bitmit, coingig or even all those .onion sites and the mediators do just fine - but these sites require you to fully trust them, as they expect the coins to be deposited in their wallet and the buyer presses a "release button", as opposed to a multisig address, where no single person can steal them or claim they've been hacked, etc etc..

I also suspect many highly trusted sellers would just accept payment directly anyway.

Anyway, unless I've miss understood your suggestion, it is not possible to do as payments can not be "cancelled".

All the best

[OutCast3k]

I would be cool if someone could make an easy android app to arrange and start a poker match.
So everyone will be able to play poker everywhere with just their smartphone and empty pockets

Nice idea... final project could be pretty awesome.

[em]

You've mentioned that the sellers maybe put at a disadvantage here because the buyer may not sign the transaction, well, there are many tried and tested sites where this type of system works. Such as; localbitcoins, bitmit, coingig or even all those .onion sites - but these sites require you to fully trust them, as they expect the coins to be deposited in their wallet and the buyer presses a "release button", as opposed to a multisig address, where no single person can steal them or claim they've been hacked, etc etc..

Exactly: here we are trying to avoid the need for trusted third parties policing the transactions. And often they rely on a separate trust metrics for assessing the participants: for example, Bitcoin.de has a system of mutual ratings among users based on the number of successful settlements, and each user's rating is visible to all other users. But this requires a centralized database and someone to maintain it, and we don't want that.

Anyway, unless I've miss understood your suggestion, it is not possible to do as payments can not be "cancelled".

However (please correct me if I'm wrong), I guess it's possible to make a transaction that will pay part of the amount sent to the script hash to one address (the Seller) and part to another (the Buyer). If the Buyer reneged on his agreement and refused to sign and broadcast the transaction after receiving the goods, he would have to forfeit the bond.

[RagnarDanneskjold]

You've mentioned that the sellers maybe put at a disadvantage here because the buyer may not sign the transaction, well, there are many tried and tested sites where this type of system works. Such as; localbitcoins, bitmit, coingig or even all those .onion sites - but these sites require you to fully trust them, as they expect the coins to be deposited in their wallet and the buyer presses a "release button", as opposed to a multisig address, where no single person can steal them or claim they've been hacked, etc etc..

Exactly: here we are trying to avoid the need for trusted third parties policing the transactions. And often they rely on a separate trust metrics for assessing the participants: for example, Bitcoin.de has a system of mutual ratings among users based on the number of successful settlements, and each user's rating is visible to all other users. But this requires a centralized database and someone to maintain it, and we don't want that.

Anyway, unless I've miss understood your suggestion, it is not possible to do as payments can not be "cancelled".

However (please correct me if I'm wrong), I guess it's possible to make a transaction that will pay part of the amount sent to the script hash to one address (the Seller) and part to another (the Buyer). If the Buyer reneged on his agreement and refused to sign and broadcast the transaction after receiving the goods, he would have to forfeit the bond.

there are a number of ways you could arrange a multisig contract to address what you call bond forfeiture.  Just to be sure, in its basic form, if the multisig address requires more signatures than are available to sign the tx, then funds will remain locked, yes.  So there is extra burden on all parties to be sure keys are safe & available on time.... or, depending on the details & complexity of agreement - additional signer keys could be used, shared, split or other tricks to build in failsafes.

here is an example of an exchange implementation using Outkast's multisig [thanks again - much fun]
http://isx.io

your question 'is it possible to implement this protocol with p2sh primitives?" - p2sh could be html javascripted just like this one if thats what you mean.

See also:
https://github.com/bitcoin/bips/blob/master/bip-0016.mediawiki
https://github.com/bitcoin/bips/blob/master/bip-0017.mediawiki
https://github.com/bitcoin/bips/blob/master/bip-0012.mediawiki
http://bitcoin.stackexchange.com/questions/2749/what-is-an-explanation-of-the-p2sh-voting-in-laymans-terms

[em]

here is an example of an exchange implementation using Outkast's multisig [thanks again - much fun]
http://isx.io

Very interesting, thanks.

[Miner538]

I would be cool if someone could make an easy android app to arrange and start a poker match.
So everyone will be able to play poker everywhere with just their smartphone and empty pockets

Nice idea... final project could be pretty awesome.

OutCast3k +10000

Great idea, this is going to change the way people view crypto's
Thank you for finding a really neat solution to a safer pay method

[OutCast3k]

I would be cool if someone could make an easy android app to arrange and start a poker match.
So everyone will be able to play poker everywhere with just their smartphone and empty pockets

Nice idea... final project could be pretty awesome.

OutCast3k +10000

Great idea, this is going to change the way people view crypto's
Thank you for finding a really neat solution to a safer pay method

No problem, I'm just glad to see others find this useful

[fbueller]

bitcoinqt and electrum send to them.
Which is ridiculous, p2sh addresses have been out for years.

Bitcoinj recently added support for p2sh, so I'm expecting the android clients will support them soon.

[Abdussamad]

How does your mediation service work? Specifically:

- Does your 1% fee apply to every transaction or only those transactions involving disputes?

- bitrated has a field where you can enter a transaction agreement or contract that specifies, among other things, what the modes of payment will be and what proof of payment must be provided in the event of a dispute. There is no such field on coinb.in. So how would you decide what to do in the event of a dispute?

[OutCast3k]

How does your mediation service work? Specifically:

- Does your 1% fee apply to every transaction or only those transactions involving disputes?

- bitrated has a field where you can enter a transaction agreement or contract that specifies, among other things, what the modes of payment will be and what proof of payment must be provided in the event of a dispute. There is no such field on coinb.in. So how would you decide what to do in the event of a dispute?

Hey,

As it stands, the 1% fee would only be applied to those transactions involving disputes.

Most users here seem to make an agreement and sign it with their PGP key in the event a dispute arises, a few other users will get in touch first. Saying that, I suppose a possible solution could be to have users create a message/agreement and sign it (in the browser) with their corresponding private key and then that could be used by the mediator if their is a dispute.

Do you have suggestions or preferences yourself? (or anybody else?)