Step CLI

step is a toolkit for working with your public key infrastructure (PKI). It's also the client counterpart to the step-ca online Certificate Authority (CA).

Here's a quick example, combining step oauth and step crypto to get and verify the signature of a Google OAuth OIDC token:

Questions? Ask us on GitHub Discussions.

Website | Documentation | Installation Guide | Examples | FAQs | Contributor's Guide

Features

Step CLI's command groups illustrate some of its uses:

• step certificate: Work with X.509 (TLS/HTTPS) certificates.

  • Create, revoke, validate, lint, and bundle X.509 certificates.
  • Install (and remove) X.509 certificates into your system's (and brower's) trust store.
  • Create key pairs (RSA, ECDSA, EdDSA) and certificate signing requests (CSRs)
  • Sign CSRs
  • Create RFC5280 and CA/Browser Forum-compliant certificates that work for TLS and HTTPS
  • Create CA certificates (root and intermediate signing certificates)
  • Create self-signed & CA-signed certificates
  • Inspect and lint certificates on disk or in use by a remote server
  • Install root certificates so your CA is trusted by default (issue development certificates that work in browsers)

• step ca: Set up your own CA, or make requests of any ACMEv2 (RFC8555) CA, including step-ca. ACME is the protocol used by Let's Encrypt to automate the issuance of HTTPS certificates.

  • Initialize an X.509 and/or SSH CA in one command
  • Authenticate and obtain a certificate using any enrollment mechanism supported by step-ca
  • Securely distribute root certificates and bootstrap PKI relying parties
  • Renew and revoke certificates issued by step-ca
  • Submit CSRs to be signed by step-ca

• step crypto: A general-purpose crypto toolkit

  • Work with JWTs (RFC7519) and other JOSE constructs
    • Sign, verify, and inspect JSON Web Tokens (JWTs)
    • Sign, verify, and inspect arbitrary data using JSON Web Signature (JWS)
    • Encrypt and decrypt data and wrap private keys using JSON Web Encryption (JWE)
    • Create JWKs and manage key sets for use with JWT, JWE, and JWS
  • Generate and verify TOTP tokens for multi-factor authentication (MFA)
  • Work with NaCl's high-speed tools for encryption and signing
  • Apply key derivation functions (KDFs) and verify passwords using scrypt, bcrypt, and argo2
  • Generate and check file hashes

• step oauth: Add an OAuth 2.0 single sign-on flow to any CLI application.

  • Supports OAuth authorization code, out-of-band (OOB), JWT bearer, and refresh token flows
  • Get OAuth access tokens and OIDC identity tokens at the command line from any provider.
  • Verify OIDC identity tokens (step crypto jwt verify)

• step ssh: Create and manage SSH certificates (requires an online or offline step-ca instance)

  • Generate SSH user and host key pairs and short-lived certificates
  • Add and remove certificates to the SSH agent
  • Inspect SSH certificates
  • Login and use single sign-on SSH

Installation

These instructions will install the step binary on your local machine. To build from source, see getting started with development.

macOS

Install step via Homebrew:

$ brew install step

Debian Linux

Download and install the Debian package from our latest release:

$ wget https://github.com/smallstep/cli/releases/download/vX.Y.Z/step-cli_X.Y.Z_amd64.deb
$ sudo dpkg -i step-cli_X.Y.Z_amd64.deb

Arch Linux

We are using the Arch User Repository to distribute step binaries for Arch Linux.

• The step-cli binary tarball can be found here.
• The step-ca binary tarball (for step certificates - a sibling repository) can be found here.

You can use yay or pacman to install the packages.

$ yay -S step-cli-bin step-ca-bin

Linux (other)

We have amd64, arm64, and armv7 releases available to download from our latest release.

Testing your installation

$ step certificate inspect https://smallstep.com
Certificate:
    Data:
        Version: 3 (0x2)
        Serial Number: 326381749415081530968054238478851085504954 (0x3bf265673332db2d0c70e48a163fb7d11ba)
    Signature Algorithm: SHA256-RSA
        Issuer: C=US,O=Let's Encrypt,CN=Let's Encrypt Authority X3
        Validity
            Not Before: Feb 8 13:07:44 2019 UTC
            Not After : May 9 13:07:44 2019 UTC
        Subject: CN=smallstep.com
[...]

Examples

Work with X.509 Certificates from step-ca

This example assumes you already have step-ca running at https://ca.local.

Get your root certificate fingerprint (run this on the step-ca server):

$ step certificate fingerprint $(step path)/certs/root_ca.crt
0eea955785796f0a103637df88f29d8dfc8c1f4260f35c8e744be155f06fd82d

On a new machine, connect to step-ca and configure your local CA client:

$ step ca bootstrap --ca-url https://ca.local \
                    --fingerprint 0eea955785796f0a103637df88f29d8dfc8c1f4260f35c8e744be155f06fd82d

Now create a key pair, generate a CSR, and get a certificate from step-ca:

$ step ca certificate foo.local foo.crt foo.key
Use the arrow keys to navigate: ↓ ↑ → ←
What provisioner key do you want to use?
  ▸ [email protected] (JWK) [kid: XXX]
✔ Please enter the password to decrypt the provisioner key: ...
✔ CA: https://ca.local
✔ Certificate: foo.crt
✔ Private Key: foo.key

Use step certificate inspect to check our work:

$ step certificate inspect --short foo.crt
X.509v3 TLS Certificate (ECDSA P-256) [Serial: 2982...2760]
  Subject:     foo.local
  Issuer:      Intermediate CA
  Provisioner: [email protected] [ID: EVct...2B-I]
  Valid from:  2019-08-31T00:14:50Z
          to:  2019-09-01T00:14:50Z

Renew a certificate, using the CA's default validity policy:

$ step ca renew foo.crt foo.key --force
Your certificate has been saved in foo.crt.

Revoke a certificate:

$ step ca revoke --cert foo.crt --key foo.key
✔ CA: https://ca.local
Certificate with Serial Number 202784089649824696691681223134769107758 has been revoked.

$ step ca renew foo.crt foo.key --force
error renewing certificate: Unauthorized

You can install your root certificate locally:

$ step certificate install $(step path)/certs/root_ca.crt

Now, all certificates issued by your CA will work in your browser and with tools like curl. See our blog post for more info.

Alternatively, for internal service-to-service communication, you can configure your code and infrastructure to trust your root certificate.

More X.509 Examples

The step certificate command group can also be used to create an offline CA and self-signed certificates.

Create a self-signed certificate:

$ step certificate create foo.local foo.crt foo.key --profile self-signed --subtle
Your certificate has been saved in foo.crt.
Your private key has been saved in foo.key.

Create a root CA, an intermediate, and a leaf X.509 certificate. Bundle the leaf with the intermediate for use with TLS:

$ step certificate create --profile root-ca \
     "Example Root CA" root-ca.crt root-ca.key
Please enter the password to encrypt the private key:
Your certificate has been saved in root-ca.crt.
Your private key has been saved in root-ca.key.

$ step certificate create \
     "Example Intermediate CA 1" intermediate-ca.crt intermediate-ca.key \
     --profile intermediate-ca --ca ./root-ca.crt --ca-key ./root-ca.key
Please enter the password to decrypt ./root-ca.key:
Please enter the password to encrypt the private key:
Your certificate has been saved in intermediate-ca.crt.
Your private key has been saved in intermediate-ca.key.

$ step certificate create \
     example.com example.com.crt example.com.key \
     --profile leaf --ca ./intermediate-ca.crt --ca-key ./intermediate-ca.key
Please enter the password to decrypt ./intermediate-ca.key:
Please enter the password to encrypt the private key:
Your certificate has been saved in example.com.crt.
Your private key has been saved in example.com.key.

$ step certificate bundle \
     example.com.crt intermediate-ca.crt example.com-bundle.crt
Your certificate has been saved in example.com-bundle.crt.

Extract the expiration date from a certificate (requires jq):

$ step certificate inspect example.com.crt --format json | jq -r .validity.end
2019-02-28T17:46:16Z

$ step certificate inspect https://smallstep.com --format json | jq -r .validity.end
2019-05-09T13:07:44Z

Work with JOSE objects (JWK, JWT)

Create a JSON Web Key (JWK), add the public key to a keyset, and sign a JSON Web Token (JWT):

$ step crypto jwk create pub.json key.json
Please enter the password to encrypt the private JWK:
Your public key has been saved in pub.json.
Your private key has been saved in key.json.

$ cat pub.json | step crypto jwk keyset add keys.json

$ JWT=$(step crypto jwt sign \
    --key key.json \
    --iss "[email protected]" \
    --aud "[email protected]" \
    --sub "[email protected]" \
    --exp $(date -v+15M +"%s"))
Please enter the password to decrypt key.json:

# Verify your JWT and return the payload:
$ echo $JWT | step crypto jwt verify \
    --jwks keys.json --iss "[email protected]" --aud "[email protected]"
{
  "header": {
    "alg": "ES256",
    "kid": "X6yaHYNyxr-psAqvSNKCWc9oYDetvGdo2n2PSRZjxss",
    "typ": "JWT"
  },
  "payload": {
    "aud": "[email protected]",
    "exp": 1551290879,
    "iat": 1551289983,
    "iss": "[email protected]",
    "nbf": 1551289983,
    "sub": "[email protected]"
  },
  "signature": "JU7fPGqBJcIfauJHA7KP9Wp292g_G9s4bLMVLyRgEQDpL5faaG-3teJ81_igPz1zP7IjHmz8D6Gigt7kbnlasw"
}

Single Sign-On OAuth OIDC tokens

Here we'll use step to run through an OAuth 2.0 authorization code flow with Google, and obtain an OIDC token. You'll need an OAuth Client ID and Client Secret from Google Cloud Platform's Credentials panel.

Login with Google and obtain an OAuth OIDC identity token for single sign-on:

$ step oauth \
    --provider https://accounts.google.com \
    --client-id 1087160488420-8qt7bavg3qesdhs6it824mhnfgcfe8il.apps.googleusercontent.com \
    --client-secret udTrOT3gzrO7W9fDPgZQLfYJ \
    --bare --oidc
Your default web browser has been opened to visit:

https://accounts.google.com/o/oauth2/v2/auth?client_id=[...]

xxx-google-xxx.yyy-oauth-yyy.zzz-token-zzz

That outputs the raw JWT. Now let's decode it and verify its signature:

$ step oauth \
     --provider https://accounts.google.com \
     --client-id 1087160488420-8qt7bavg3qesdhs6it824mhnfgcfe8il.apps.googleusercontent.com \
     --client-secret udTrOT3gzrO7W9fDPgZQLfYJ \
     --bare --oidc \
     | step crypto jwt verify \
       --jwks https://www.googleapis.com/oauth2/v3/certs \
       --iss https://accounts.google.com \
       --aud 1087160488420-8qt7bavg3qesdhs6it824mhnfgcfe8il.apps.googleusercontent.com
Your default web browser has been opened to visit:

https://accounts.google.com/o/oauth2/v2/auth?client_id=[...]

{
  "header": {
    "alg": "RS256",
    "kid": "f24d6a1930669cb75f19",
    "typ": "JWT"
  },
  "payload": {
    "iss": "https://accounts.google.com",
    "azp": "1087160488420-8qt7bavg3qesdhs6it824mhnfgcfe8il.apps.googleusercontent.com",
    "aud": "1087160488420-8qt7bavg3qesdhs6it824mhnfgcfe8il.apps.googleusercontent.com",
    "sub": "103209689286000948507",
    "hd": "smallstep.com",
    "email": "[email protected]",
    "email_verified": true,
    "at_hash": "euBvS34BVu0SJQ-EsbBT3A",
    "iat": 1551293134,
    "exp": 1551296734
  },
  "signature": "[...]"
}

OAuth 2.0 API calls

Here's another flow. Let's use step to get a Google bearer token using OAuth 2.0, make an HTTP Authorization: header from it, and use curl to make a request to Google's APIs:

$ curl -H"$(step oauth --header)" https://www.googleapis.com/oauth2/v3/userinfo
Your default web browser has been opened to visit:

https://accounts.google.com/o/oauth2/v2/auth?client_id=1087160488420-AAAAAAAAAAAAAAA.apps.googleusercontent.com&code_challenge=XXXXX

{
  "sub": "AAAAAAAAAAAAA",
  "picture": "https://lh6.googleusercontent.com/photo.jpg",
  "email": "[email protected]",
  "email_verified": true,
  "hd": "smallstep.com"
}

Multi-factor Authentication

Generate a TOTP token and a QR code:

$ step crypto otp generate \
    --issuer smallstep.com --account [email protected] \
    --qr smallstep.png > smallstep.totp

Scan the QR Code (smallstep.png) using Google Authenticator, Authy or similar software and use it to verify the TOTP token:

$ step crypto otp verify --secret smallstep.totp

Community

• Connect with step users on GitHub Discussions
• Open an issue and tell us what features you'd like to see
• Follow Smallstep on Twitter

Further Reading

• Full documentation for step
• We have more examples of step and step-ca in action on the Smallstep blog.
• If you're new to PKI and X.509 certificates, or you want a refresher on the core concepts, you may enjoy Everything PKI.