letsencrypt/acme client implemented as a shell-script
Shell
Latest commit 6192b33 Aug 22, 2016 @leonklingele leonklingele committed with ECDSA is supported since February 10, 2016 (#260)
Let's Encrypt will however sign all ECDSA certs with an RSA intermediate certificate.
https://letsencrypt.org/upcoming-features/

README.md

letsencrypt.sh Build Status

This is a client for signing certificates with an ACME-server (currently only provided by letsencrypt) implemented as a relatively simple bash-script.

It uses the openssl utility for everything related to actually handling keys and certificates, so you need to have that installed.

Other dependencies are: curl, sed, grep, mktemp (all found on almost any system, curl being the only exception)

Current features:

  • Signing of a list of domains
  • Signing of a CSR
  • Renewal if a certificate is about to expire or SAN (subdomains) changed
  • Certificate revocation

Please keep in mind that this software and even the acme-protocol are relatively young and may still have some unresolved issues. Feel free to report any issues you find with this script or contribute by submitting a pullrequest.

Getting started

For getting started I recommend taking a look at docs/domains_txt.md, docs/wellknown.md and the Usage section on this page (you'll probably only need the -c option).

Generally you want to set up your WELLKNOWN path first, and then fill in domains.txt.

Please note that you should use the staging URL when experimenting with this script to not hit letsencrypts rate limits. See docs/staging.md.

If you have any problems take a look at our Troubleshooting guide.

Usage:

Usage: ./letsencrypt.sh [-h] [command [argument]] [parameter [argument]] [parameter [argument]] ...

Default command: help

Commands:
 --cron (-c)                      Sign/renew non-existant/changed/expiring certificates.
 --signcsr (-s) path/to/csr.pem   Sign a given CSR, output CRT on stdout (advanced usage)
 --revoke (-r) path/to/cert.pem   Revoke specified certificate
 --cleanup (-gc)                  Move unused certificate files to archive directory
 --help (-h)                      Show help text
 --env (-e)                       Output configuration variables for use in other scripts

Parameters:
 --full-chain (-fc)               Print full chain when using --signcsr
 --ipv4 (-4)                      Resolve names to IPv4 addresses only
 --ipv6 (-6)                      Resolve names to IPv6 addresses only
 --domain (-d) domain.tld         Use specified domain name(s) instead of domains.txt entry (one certificate!)
 --keep-going (-g)                Keep going after encountering an error while creating/renewing multiple certificates in cron mode
 --force (-x)                     Force renew of certificate even if it is longer valid than value in RENEW_DAYS
 --no-lock (-n)                   Don't use lockfile (potentially dangerous!)
 --ocsp                           Sets option in CSR indicating OCSP stapling to be mandatory
 --privkey (-p) path/to/key.pem   Use specified private key instead of account key (useful for revocation)
 --config (-f) path/to/config     Use specified config file
 --hook (-k) path/to/hook.sh      Use specified script for hooks
 --out (-o) certs/directory       Output certificates into the specified directory
 --challenge (-t) http-01|dns-01  Which challenge should be used? Currently http-01 and dns-01 are supported
 --algo (-a) rsa|prime256v1|secp384r1 Which public key algorithm should be used? Supported: rsa, prime256v1 and secp384r1