gokey

A simple vaultless password manager in Go

gokey is a password manager, which does not require a password vault. Instead of storing your passwords in a vault it derives your password on the fly from your master password and supplied realm string (for example, resource URL). This way you do not have to manage, backup or sync your password vault (or trust its management to a third party) as your passwords are available immediately anywhere.

example

gokey -p super-secret-master-password -r example.com

options

• -o <output path> - by default gokey outputs generated data to stdout
• -P </path/to/password> - path to master password file which will be used to generate other passwords/keys or to encrypt seed file (see Modes of operation below, if no master password or master password file is provided, gokey will ask for it interactively)
• -p <master password> - master password which will be used to generate other passwords/keys or to encrypt seed file (see Modes of operation below, if no master password or master password file is provided, gokey will ask for it interactively)
• -r <password/key realm> - any string which identifies requested password/key, most likely key usage or resource URL
• -s <path to seed file> - needed, if you want to use seed file instead of master password as an entropy source (see Modes of operation below); can be generated with -t seed flag as described below
• -skip <number of bytes> - number of bytes to skip when reading seed file
• -u - UNSAFE, allow generating keys without using a seed file (see Modes of operation below)
• -t <password/key type> - requested password/key output type
• -l <length> - number of characters in the generated password or number of bytes in the generated raw stream (default 10 for "pass" type and 32 for "raw" type)

Supported password/key types:

• pass - default, generates a password
• seed - generates a seed file, which can be used with -s option later
• raw - generates 32 random bytes (can be used as a symmetric key)
• ec256 - generates ECC P-256 private key
• ec521 - generates ECC P-521 private key
• rsa2048 - generates 2048-bit RSA private key
• rsa4096 - generates 4096-bit RSA private key
• x25519 - generates x25519 (also known as curve25519) ECC private key
• ed25519 - generates ed25519 ECC private key

Installation

gokey command-line utility can be downloaded and compiled using standard go get approach. Assuming you have Go installed and $GOPATH set, just do

go get github.com/cloudflare/gokey/cmd/gokey

The gokey binary should appear in your $GOPATH/bin directory.

Modes of operation

gokey can generate passwords and cryptographic private keys (ECC and RSA keys are currently supported). However, without any additional options specified it uses your master password as a single source of entropy for generated data. For passwords it is acceptable most of the time, but keys usually have much higher entropy requirements.

For cases, where higher entropy is required for generated passwords/keys, gokey can use a seed file (a blob with random data) instead of the master password as a source of entropy.

Simple mode (without a seed file)

In simple mode passwords are derived directly from your master password and the realm string. That is each unique combination of a master password and a realm string will produce a unique password.

For example, if your master password is super-secret-master-password and you want to generate a password for example.com, you would invoke gokey like

gokey -p super-secret-master-password -r example.com

If you need a password for a different resource, (example2.com), you would change the real string

gokey -p super-secret-master-password -r example2.com

This way you need to remember only your master password and you can always recreate passwords for your services/resources.

NOTE: In this mode generated passwords are as strong as your master password, so do have your master password strong enough. You can also derive private keys from your master password, but keep in mind, that these keys will have low entropy. That is why it is considered unsafe, so gokey does not allow it by default. If you're really know what you are doing, you can override this default by supplying -u flag.

Using a seed file

If you plan to generate not only passwords, but also private keys or you want to have your passwords/keys with higher entropy, you can use a seed file instead of the master password. You still need to supply a master password, when invoking gokey, but it will be used only to protect the seed file itself; all generated passwords/keys will be derived from the data in the seed file. gokey uses seed files protected (encrypted) with your master password, so it is reasonably safe to store/backup seed files to a third party location, such as Google Drive or Dropbox.

To generate an encrypted seed file, use

gokey -p super-secret-master-password -t seed -o seedfile

This will create a seed file seedfile with 256 bytes of random data. The data is encrypted using AES-256-GCM mode and super-secret-master-password as a key.

Then, to generate EC-256 private key for example.com, use

gokey -p super-secret-master-password -s seedfile -r example.com -t ec256

NOTE: you still need to remember your master password and keep a backup copy of your seed file. If you forget your master password or loose your seed file, you loose all derived passwords/keys as well.