openpgp-card-app/README.md

# GnuPG application

GnuPG application for Nano S and Nano X

This application implements "The OpenPGP card" specification revision 3.3.
This specification is available in *doc* directory and at <https://g10code.com/p-card.html>.

The application supports:

- RSA with key up to 4096 bits
- ECDSA with secp256k1
- EDDSA with Ed25519 curve
- ECDH with secp256k1 and curve25519 curves

This release has known missing parts (see also Add-on) :

- Ledger Blue support
- Seed mode ON/OFF via apdu

## Installation and Usage

See the full doc at <https://github.com/LedgerHQ/blue-app-openpgp-card/blob/master/doc/user/blue-app-openpgp-card.pdf>

## Add-on

The GnuPG application implements the following addon:

- serial modification
- on screen reset
- 3 independent key slots
- seeded key generation

Technical specification is available at <https://github.com/LedgerHQ/blue-app-openpgp-card/blob/master/doc/developer/gpgcard3.0-addon.rst>

### Key slot

"The OpenPGP card" specification specifies:

- 3 asymmetric keys : Signature, Decryption, Authentication
- 1 symmetric key

The application allows you to store 3 different key sets, named slot. Each slot contains the above 4 keys.
You can choose the active slot on the main screen.
When installed the default slot is "1". You can change it in settings.

### seeded key generation

A seeded mode is implemented in order to restore private keys on a new token.
In this mode key material is generated from the global token seeded.

Please consider SEED mode as experimental.

More details to come...

### On screen reset

The application can be reset as if it was fresh installed. In settings, choose reset and confirm.