Hey,
Firstly, your project coinb.in is really cool, I've used it a bit back in the day :-)
It makes sense why you're looking for this proposal. I'm pretty sure on top of a serialisation of an unsigned tx with the scriptpubkey (it is to deliver signing data to the wallet too?) then you'll also want a protocol to request signatures.
I worked on this problem before, when I was using your site and a tool of mine to carry out transactions. I would up writing a BIP that's basically the same (in message contents, not format) as Jonas's hardware signing BIP.
I think he also realised that it's not just for hardware wallets, it's also perfect for a BitGo wallet to use to talk to a GreenAddress wallet. It seems to cover the web case nicely.
(My app was one where users could supply an xpub for multisigs to the server, get txs, and do signing offline or in the browser)
Maybe have a look over it and see if it starts to capture some of the things you would want!
All the best,
Thomas--
On 9 January 2017 10:36:49 CET, "木ノ下じょな via bitcoin-dev" <bitcoin-dev@lists.linuxfoundation.org > wrote:I have been seeing issues like the following many times on all the different projects that support multisig with users responsible for partial transaction transport.I would like to gather opinions before proposing a BIP, (like whether we need one or not) so please let me know what you think.Basically, Electrum, Copay, Coinb.in, Bitcoin Core, etc. all have different methodology for serializing partially signed multisig raw transactions, as well as not-signed raw transactions regardless of scriptPubkey.I think we should all be on the same page when serializing not-signed and partially signed transactions so that the person could look at the data alone and know what is necessary and how to manipulate it to sign and complete the transaction.- Jon-------BEGIN PGP PUBLIC KEY BLOCK-----Comment: http://openpgpjs.orgxsBNBFTmJ8oBB/9rd+7XLxZG/x/KnhkVK2WBG8ySx91fs+ qQfHIK1JrakSV3 x6x0cK3XLClASLLDomm7Od3Q/fMFzdwCEqj6z60T8wgKxsjWYSGL3mq 8ucdv iBjC3wGauk5dQKtT7tkCFyQQbX/uMsBM4ccGBICoDmIJlwJIj7fAZVqGx GOM bO1RhYb4dbQA2qxYP7wSsHJ6/ZNAXyEphOj6blUzdqO0exAbCOZWWF+ E/1SC EuKO4RmL7Imdep7uc2Qze1UpJCZx7ASHl2IZ4UD0G3Qr3pI6/jvNlaqCTa3U 3/YeJwEubFsd0AVy0zs809RcKKgX3W1q +hVDTeWinem9RiOG/vT+Eec/ABEB AAHNI2tpbm9zaGl0YSA8a2lub3NoaXRham9uYUBnbWFpbC5jb20+wsByBBAB CAAmBQJU5ifRBgsJCAcDAgkQRB9iZ30dlisEFQgCCgMWAgECGwMCHgEAAC6Z B/9otobf0ASHYdlUBeIPXdDopyjQhR2R iZGYaS0VZ5zzHYLDDMW6ZIYm5CjO Fc09ETLGKFxH2RcCOK2dzwz+KRU4xqOrt/l5gyd50cFE1nOhUN9+/ XaPgrou WhyT9xLeGit7Xqhht93z2+VanTtJAG6lWbAZLIZAMGMuLX6sJDCO 0GiO5zxa 02Q2D3kh5GL57A5+oVOna12JBRaIA5eBGKVCp3KToT/ z48pxBe3WAmLo0zXr hEgTSzssfb2zTwtB3Ogoedj+cU2bHJvJ8upS/ jMr3TcdguySmxJlGpocVC/e qxq12Njv+LiETOrD8atGmXCnA+nFNljBkz+ l6ADl93jHzsBNBFTmJ9EBCACu Qq9ZnP+aLU/Rt6clAfiHfTFBsJvLKsdIKeE6qHzsU 1E7A7bGQKTtLEnhCCQE W+OQP+sgbOWowIdH9PpwLJ3Op+NhvLlMxRvbT36LwCmBL0yD7bMqxxmm Vj8n vlMMRSe4wDSIG19Oy7701imnHZPm/pnPlneg/Meu/ UffpcDWYBbAFX8nrXPY vkVULcI/qTcCxW/+S9fwoXjQhWHaiJJ6y3cYOSitN31W9z gcMvLwLX3JgDxE flkwq/M+ZkfCYnS3GAPEt8GkVKy2eHtCJuNkGF lCAmKMX0yWzHRAkqOMN5KP LFbkKY2GQl13ztWp82QYJZpj5af6dmyUosurn6AZABEBAAHCwF8EGAEIABMF AlTmJ9QJEEQfYmd9HZYrAhsMAABKbgf/Ulu5JAk4fXgH0DtkMmdkFiKEFdkW 0Wkw7Vhd5eZ4NzeP9kOkD01OGweT9hqzwhfT2CNXCGxh4UnvEM1ZMFypIKdq 0XpLLJMrDOQO021UjAa56vHZPAVmAM01z5VzHJ7ekjgwrgMLmVkm0jWKEKaO n/MW7CyphG7QcZ6cJX2f6uJcekBlZRw9 TNYRnojMjkutlOVhYJ3J78nc/k0p kcgV63GB6D7wHRF4TVe4xIBqKpbBhhN+ISwFN1z+gx3lfyRMSmiTSrGdKEQe XSIQKG8XZQZUDhLNkqPS+7EMV1g7+lOfT4GhLL68dUXDa1e9YxGH6zkpVEC w Spe3vsHZr6CqFg===/vUJ-----END PGP PUBLIC KEY BLOCK-----
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