generate zpub for segwit address

[lsching17]

There is an example for generate segwit address

trezorctl get_address --coin Bitcoin --script-type segwit --address "m/84'/0'/0'/0/0"

There is another example to generate xpub

trezorctl get_public_node --coin Bitcoin --address "m/44'/0'/0'"

So, how to generate pub key for p2shsegwit and segwit (e.g. zpub)? if "m/84'/0'/0'/0/0" is passed, "zpub" is still returned.

[prusnak]

@matejcik Currently there is no way how to pass type of requested pubkey via GetPublicKey message. Wallet solves this for Segwit accounts (BIP-49) by deserializing xpub, changing it's version and serializing back to text.

Quick solution would to be to detect first two elements of the path and do the conversion from xpub prefix to another one (according to table here:) https://github.com/satoshilabs/slips/blob/master/slip-0132.md#registered-hd-version-bytes

[matejcik]

@prusnak that sounds about right. The key material is still the same, right? So basically it's only a matter of sticking the right word at start?

[lsching17]

This is too difficult for bitcoin novice: how to convert xpub to zpub in bash or python?

[prusnak]

So basically it's only a matter of sticking the right word at start?

not sticking, deserializing, changing the version and serializing back

[lsching17]

Can the library add support to generate xpub, ypub, zpub in the future?

[prusnak]

Yes, will update this in the future.

[prusnak]

Added script_type param to GetPublicKey in the following commit: https://github.com/trezor/trezor-common/commit/a01a9cef9e8690e998839be719880925c5991231

[prusnak]

Implemented in https://github.com/trezor/python-trezor/commit/555bb62e3f7f5a9fcaca301f10ab9f977c87a8dd

Next firmware release will contain this feature.

[prusnak]

T2 firmware implemented in https://github.com/trezor/trezor-core/commit/ebdd8c9b07537351c7dedec4db6e1fcbeb0426ef

[prusnak]

T1 firmware implemented in https://github.com/trezor/trezor-mcu/commit/efeedbe69b7fa9845462775c7a528c4f1838b7d8