Trezor Multi Signature

[RustyNomad]

Can anybody possibly give me a grade 5 ( ) explanation of how Trezor works with multi signature.

From what I've tried it seems like you cannot setup a multi sig wallet on a Trezor but rather use the Trezor, or one of the wallets on it, to act as one of the signatures on a multi sig wallet on say Electrum?

Is this correct or have I lost the plot?

[johoe]

Can anybody possibly give me a grade 5 ( ) explanation of how Trezor works with multi signature.

From what I've tried it seems like you cannot setup a multi sig wallet on a Trezor but rather use the Trezor, or one of the wallets on it, to act as one of the signatures on a multi sig wallet on say Electrum?

Is this correct or have I lost the plot?

I think you are correct.  I only tried multi-sig on Trezor once with greenaddress.  I haven't tried Electrum yet. The idea is that the Trezor controls one address, the other addresses are controlled by other bip32 compatible wallets, e.g., other Trezors.

AFAIK it only works if all input addresses and the change address are multisig addresses with the same number of keys and the public keys are derived from the same bip32 master keys.

[RustyNomad]

Is there anybody who actually have a multi signature setup on Electrum with Trezor who can give me a quick short step by step of how it works?

I've been thinking of setting up a multi signature wallet but don't really see how it could add any more security to the setup I currently have. I currently make use of a Trezor on which my primary wallets are. These are all replicated on Electrum which essentially acts as watch only wallets unless I plug the Trezor in.

So currently I'm essentially working with offline wallets which for me seems secure enough so not sure whether a multi signature setup could add more security and or whether it will just complicate things.

Any thoughts on this?

[AussieHash]

Electrum multisig + Trezor was just fixed by 2 pull requests in the past 48 hours, however you will need to clone the latest repository (or wait until 2.4.5 binaries are released)

git clone https://github.com/spesmilo/electrum
cd electrum
python setup.py install
./electrum

Create a Trezor electrum wallet (or open an existing one)
Copy the xpub from this Trezor electrum wallet
Close the Trezor electrum wallet

Create a new multisig electrum wallet
For this example try 2 of 2
Paste the Trezor electrum wallet xpub in the second box

Send some bits to your multisig address, should start with 3XXXXXXX

Create a spend transaction - optional whether you sign or not.
Either copy or save transaction, either unsigned or with 1 signature
Close your multisig electrum wallet

Open your Trezor electrum  wallet, enter PIN/Passphrase as required.
Load transaction from text (paste the transaction from earlier)
Sign
Optionally broadcast

Addendum : this was broken until about 12 hours ago, I wouldn't trust your life's savings with this yet.
I think the only production ready multisig solutions at the moment are Coinkite +/- Ledger multisig, Bitgo and Armory.

Copay and GreenAddress have been working alot longer than 12 hours, but are not production ready IMHO

[RustyNomad]

Thanks for the update and the detailed steps.

I'll keep an eye out for the 2.4.5 binaries and will give the multisig a test drive.

[Fiat_Hodler]

Electrum multisig + Trezor was just fixed by 2 pull requests in the past 48 hours, however you will need to clone the latest repository (or wait until 2.4.5 binaries are released)

git clone https://github.com/spesmilo/electrum
cd electrum
python setup.py install
./electrum

Create a Trezor electrum wallet (or open an existing one)
Copy the xpub from this Trezor electrum wallet
Close the Trezor electrum wallet

Create a new multisig electrum wallet
For this example try 2 of 2
Paste the Trezor electrum wallet xpub in the second box

Send some bits to your multisig address, should start with 3XXXXXXX

Create a spend transaction - optional whether you sign or not.
Either copy or save transaction, either unsigned or with 1 signature
Close your multisig electrum wallet

Open your Trezor electrum  wallet, enter PIN/Passphrase as required.
Load transaction from text (paste the transaction from earlier)
Sign
Optionally broadcast

Addendum : this was broken until about 12 hours ago, I wouldn't trust your life's savings with this yet.
I think the only production ready multisig solutions at the moment are Coinkite +/- Ledger multisig, Bitgo and Armory.

Copay and GreenAddress have been working alot longer than 12 hours, but are not production ready IMHO

thanks for your post, I am wondering when there will be a fully functional multiple trezor multisig address feature available. this will really help with a cold storage solution (eg. spread the keys/trezors accross multiple locations).

[AussieHash]

thanks for your post, I am wondering when there will be a fully functional multiple trezor multisig address feature available. this will really help with a cold storage solution (eg. spread the keys/trezors accross multiple locations).

Apparently you can have an all Trezor multisig setup, although I haven't tried it.
https://bitcointalk.org/index.php?topic=1188182.msg12545241#msg12545241