Are wallet passphrases cached?

trezorfan123 · December 21, 2022, 9:40pm

This question involves Trezor One, Trezor Suite, and Metamask Firefox extension on M1 Mac. Latest and greatest firmware/software versions for everything.

I’m a long time user and have a good understanding of Trezor operation (I thought!), but I was confused by something recently. I have two hidden wallets with different passphrases. One of these wallets is connected to Metamask via TrezorConnect(?). I recently used this wallet and was prompted for its passphrase, made my transaction, all normal stuff. Then I went into Suite and made a transaction with my second wallet (and was prompted for its passphrase of course). Then (this is the confusing part) I went back to the first (metamask connected) wallet to make another transaction and I was not asked to re-enter its passphrase (and the transaction completed normally).

So the last passphrase that I approved via button presses on my Trezor was for Wallet 2, but my Wallet 1 (metamask connected) transaction worked fine. This kinda broke my brain because I thought only one wallet could be loaded on my Trezor at a time and I had to manually enter/approve passphrases to switch between them. Is this not the case? Is there some kind of “active session” or passphrase caching going on?

Thanks.

rimaS · December 21, 2022, 11:17pm

@trezorfan123

To my knowledge and understanding no, Passphrases are not stored anywhere…

trezorfan123 · December 23, 2022, 1:07am

My best guess is the behavior I described is somehow related to the “passphrase persistence” described at the bottom of this Trezor Connect documentation:

github.com

trezor/trezor-suite/blob/develop/docs/packages/connect/index.md

# Trezor Connect

## How to use

Initialize in project

```javascript
TrezorConnect.init({
    lazyLoad: true, // this param will prevent iframe injection until TrezorConnect.method will be called
    manifest: {
        email: '[email protected]',
        appUrl: 'http://your.application.com',
    },
});
```

Trezor Connect Manifest requires that you, as a Trezor Connect integrator, share your e-mail and application url with us.
This provides us with the **ability to reach you in case of any required maintenance.**
This subscription is mandatory. Trezor Connect raises an error that reads "Manifest not set" if manifest is not provided. It can be either set via `manifest` method or passed as a param in `init` method.

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(Sorry. I can’t post links.)

Can anyone confirm or point me to more documentation?

matejcik · December 28, 2022, 1:09pm

Yes, this is expected behavior. Since version 1.9.0, Trezor can hold 10 concurrent sessions, so you can have up to 10 “active” passphrases, and don’t need to re-enter the passphrase until the device is disconnected.

Here is more about the feature: Sessions - Trezor Firmware

rimaS · December 28, 2022, 7:29pm

Thank you @matejcik learnt something new…

trezorfan123 · December 31, 2022, 4:37pm

Thank you. That clarifies everything. I think I’ll just stop using Suite and Metamask simultaneously to avoid confusing myself!