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Keyring

Create, import, export and delete keys using the CLI keyring.

The keyring holds the private/public keypairs used to interact with the node. For instance, a validator key needs to be set up before running the node, so that blocks can be correctly signed. The private key can be stored in different locations, called "backends", such as a file or the operating system's own key storage.

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In case, you need a refresher on private key and key management, please reference our Key Management.

Add keys​

You can use the following commands for help with the keys command and for more information about a particular subcommand, respectively:

evmosd keys
evmosd keys [command] --help

To create a new key in the keyring, run the add subcommand with a <key_name> argument. You will have to provide a password for the newly generated key. This key will be used in the next section.

evmosd keys add dev0

# Put the generated address in a variable for later use.
MY_VALIDATOR_ADDRESS=$(evmosd keys show dev0 -a)

This command generates a new 24-word mnemonic phrase, persists it to the relevant backend, and outputs information about the keypair. If this keypair will be used to hold value-bearing tokens, be sure to write down the mnemonic phrase somewhere safe!

By default, the keyring generates a eth_secp256k1 key. The keyring also supports ed25519 keys, which may be created by passing the --algo flag. A keyring can of course hold both types of keys simultaneously.

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Note: The Ethereum address associated with a public key can be derived by taking the full Ethereum public key of type eth_secp256k1, computing the Keccak-256 hash, and truncating the first twelve bytes.

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NOTE: Cosmos secp256k1 keys are not supported on Evmos due to compatibility issues with Ethereum transactions.

Keyring Backends​

OS​

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os is the default option since operating system's default credentials managers are designed to meet users' most common needs and provide them with a comfortable experience without compromising on security.

The os backend relies on operating system-specific defaults to handle key storage securely. Typically, an operating system's credential sub-system handles password prompts, private keys storage, and user sessions according to the user's password policies. Here is a list of the most popular operating systems and their respective passwords manager:

GNU/Linux distributions that use GNOME as default desktop environment typically come with Seahorse. Users of KDE based distributions are commonly provided with KDE Wallet Manager. Whilst the former is in fact a libsecret convenient frontend, the latter is a kwallet client.

The recommended backends for headless environments are file and pass.

File​

The file stores the keyring encrypted within the app's configuration directory. This keyring will request a password each time it is accessed, which may occur multiple times in a single command resulting in repeated password prompts. If using bash scripts to execute commands using the file option you may want to utilize the following format for multiple prompts:

# assuming that KEYPASSWD is set in the environment
yes $KEYPASSWD | evmosd keys add me
yes $KEYPASSWD | evmosd keys show me
# start evmosd with keyring-backend flag
evmosd --keyring-backend=file start
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The first time you add a key to an empty keyring, you will be prompted to type the password twice.

Password Store​

The pass backend uses the pass utility to manage on-disk encryption of keys' sensitive data and metadata. Keys are stored inside gpg encrypted files within app-specific directories. pass is available for the most popular UNIX operating systems as well as GNU/Linux distributions. Please refer to its manual page for information on how to download and install it.

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pass uses GnuPG for encryption. gpg automatically invokes the gpg-agent daemon upon execution, which handles the caching of GnuPG credentials. Please refer to gpg-agent man page for more information on how to configure cache parameters such as credentials TTL and passphrase expiration.

The password store must be set up prior to first use:

pass init <GPG_KEY_ID>

Replace <GPG_KEY_ID> with your GPG key ID. You can use your personal GPG key or an alternative one you may want to use specifically to encrypt the password store.

KDE Wallet Manager​

The kwallet backend uses KDE Wallet Manager, which comes installed by default on the GNU/Linux distributions that ships KDE as default desktop environment. Please refer to KWallet Handbook for more information.

Testing​

The test backend is a password-less variation of the file backend. Keys are stored unencrypted on disk. This keyring is provided for testing purposes only. Use at your own risk!

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🚨 DANGER: Never create your mainnet validator keys using a test keying backend. Doing so might result in a loss of funds by making your funds remotely accessible via the eth_sendTransaction JSON-RPC endpoint.

Ref: Security Advisory: Insecurely configured geth can make funds remotely accessible

In Memory​

The memory backend stores keys in memory. The keys are immediately deleted after the program has exited.

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IMPORTANT: Provided for testing purposes only. The memory backend is not recommended for use in production environments. Use at your own risk!