Paper Wallets using the Openos CLI

This document describes how to create and use a paper wallet with the Openos CLI tools.

We do not intend to advise on how to securely create or manage paper wallets. Please research the security concerns carefully.

Overview

Openos provides a key generation tool to derive keys from BIP39-compliant seed phrases. Openos CLI commands for running a validator and staking tokens all support keypair input via seed phrases.

Paper Wallet Usage

Openos commands can be run without ever saving a keypair to disk on a machine. If avoiding writing a private key to disk is a security concern of yours, you've come to the right place.

Even using this secure input method, it's still possible that a private key gets written to disk by unencrypted memory swaps. It is the user's responsibility to protect against this scenario.

Before You Begin

• Install the Openos command-line tools

Check your installation

Check that openos-keygen is installed correctly by running:

openos-keygen --version

Creating a Paper Wallet

Using the openos-keygen tool, it is possible to generate new seed phrases as well as derive a keypair from an existing seed phrase and (optional) passphrase. The seed phrase and passphrase can be used together as a paper wallet. As long as you keep your seed phrase and passphrase stored safely, you can use them to access your account.

For more information about how seed phrases work, review this Bitcoin Wiki page.

Seed Phrase Generation

Generating a new keypair can be done using the openos-keygen new command. The command will generate a random seed phrase, ask you to enter an optional passphrase, and then will display the derived public key and the generated seed phrase for your paper wallet.

After copying down your seed phrase, you can use the public key derivation instructions to verify that you have not made any errors.

openos-keygen new --no-outfile

If the --no-outfile flag is omitted, the default behavior is to write the keypair to ~/.config/openos/id.json, resulting in a file system wallet.

The output of this command will display a line like this:

pubkey: 9ZNTfG4NyQgxy2SWjSiQoUyBPEvXT2xo7fKc5hPYYJ7b

The value shown after pubkey: is your wallet address.

Note: In working with paper wallets and file system wallets, the terms "pubkey" and "wallet address" are sometimes used interchangeably.

For added security, increase the seed phrase word count using the --word-count argument

For full usage details, run:

openos-keygen new --help

Public Key Derivation

Public keys can be derived from a seed phrase and a passphrase if you choose to use one. This is useful for using an offline-generated seed phrase to derive a valid public key. The openos-keygen pubkey command will walk you through how to use your seed phrase (and a passphrase if you chose to use one) as a signer with the openos command-line tools using the prompt URI scheme.

openos-keygen pubkey prompt://

Note that you could potentially use different passphrases for the same seed phrase. Each unique passphrase will yield a different keypair.

The openos-keygen tool uses the same BIP39 standard English word list as it does to generate seed phrases. If your seed phrase was generated with another tool that uses a different word list, you can still use openos-keygen, but will need to pass the --skip-seed-phrase-validation argument and forego this validation.

openos-keygen pubkey prompt:// --skip-seed-phrase-validation

After entering your seed phrase with openos-keygen pubkey prompt:// the console will display a string of base-58 characters. This is the derived openos BIP44 wallet address associated with your seed phrase.

Copy the derived address to a USB stick for easy usage on networked computers

If needed, you can access the legacy, raw keypair's pubkey by instead passing the ASK keyword:

openos-keygen pubkey ASK

A common next step is to check the balance of the account associated with a public key

For full usage details, run:

openos-keygen pubkey --help

Hierarchical Derivation

The openos-cli supports BIP32 and BIP44 hierarchical derivation of private keys from your seed phrase and passphrase by adding either the ?key= query string or the ?full-path= query string.

By default, prompt: will derive openos's base derivation path m/44'/501'. To derive a child key, supply the ?key=<ACCOUNT>/<CHANGE> query string.

openos-keygen pubkey prompt://?key=0/1

To use a derivation path other than openos's standard BIP44, you can supply ?full-path=m/<PURPOSE>/<COIN_TYPE>/<ACCOUNT>/<CHANGE>.

openos-keygen pubkey prompt://?full-path=m/44/2017/0/1

Because Openos uses Ed25519 keypairs, as per SLIP-0010 all derivation-path indexes will be promoted to hardened indexes -- eg. ?key=0'/0', ?full-path=m/44'/2017'/0'/1' -- regardless of whether ticks are included in the query-string input.

Verifying the Keypair

To verify you control the private key of a paper wallet address, use openos-keygen verify:

openos-keygen verify <PUBKEY> prompt://

where <PUBKEY> is replaced with the wallet address and the keyword prompt:// tells the command to prompt you for the keypair's seed phrase; key and full-path query-strings accepted. Note that for security reasons, your seed phrase will not be displayed as you type. After entering your seed phrase, the command will output "Success" if the given public key matches the keypair generated from your seed phrase, and "Failed" otherwise.

Checking Account Balance

All that is needed to check an account balance is the public key of an account. To retrieve public keys securely from a paper wallet, follow the Public Key Derivation instructions on an air gapped computer. Public keys can then be typed manually or transferred via a USB stick to a networked machine.

Next, configure the openos CLI tool to connect to a particular cluster:

openos config set --url <CLUSTER URL> # (i.e. https://api.mainnet-beta.https://openverse.network/)

Finally, to check the balance, run the following command:

openos balance <PUBKEY>

Creating Multiple Paper Wallet Addresses

You can create as many wallet addresses as you like. Simply re-run the steps in Seed Phrase Generation or Public Key Derivation to create a new address. Multiple wallet addresses can be useful if you want to transfer tokens between your own accounts for different purposes.

Support

You can find additional support and get help on the Openos StackExchange.