letsencrypt.sh 
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
- Renewal if a certificate is about to expire or SAN (subdomains) changed
- Certificate revocation
If you want to import existing keys from the official letsencrypt client have a look at Import from official letsencrypt client.
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.
Usage:
Usage: ./letsencrypt.sh [-h] [command [argument]] [parameter [argument]] [parameter [argument]] ...
Default command: help
Commands:
--cron (-c) Sign/renew non-existant/changed/expiring certificates.
--revoke (-r) path/to/cert.pem Revoke specified certificate
--help (-h) Show help text
--env (-e) Output configuration variables for use in other scripts
Parameters:
--domain (-d) domain.tld Use specified domain name(s) instead of domains.txt entry (one certificate!)
--force (-x) Force renew of certificate even if it is longer valid than value in RENEW_DAYS
--privkey (-p) path/to/key.pem Use specified private key instead of account key (useful for revocation)
--config (-f) path/to/config.sh Use specified config file
--hook (-k) path/to/hook.sh Use specified script for hooks
--challenge (-t) http-01|dns-01 Which challenge should be used? Currently http-01 and dns-01 are supported
domains.txt
The file domains.txt should have the following format:
example.com www.example.com
example.net www.example.net wiki.example.net
This states that there should be two certificates example.com and example.net,
with the other domains in the corresponding line being their alternative names.
$WELLKNOWN / challenge-response
Boulder (acme-server) is looking for challenge responses under your domain in the .well-known/acme-challenge directory
This script uses http-01-type verification (for now) so you need to have that directory available over normal http (no ssl).
A full URL would look like http://example.org/.well-known/acme-challenge/c3VjaC1jaGFsbGVuZ2UtbXVjaA-aW52YWxpZC13b3c.
An example setup to get this to work would be:
nginx.conf:
...
location /.well-known/acme-challenge {
alias /var/www/letsencrypt;
}
...
config.sh:
...
WELLKNOWN="/var/www/letsencrypt"
...An alternative to setting the WELLKNOWN variable would be to create a symlink to the default location next to the script (or BASEDIR):
ln -s /var/www/letsencrypt .acme-challenges
dns-01 challenge
This script also supports the new dns-01-type verification. Be aware that at the moment this is not available on the production servers from letsencrypt. Please read https://community.letsencrypt.org/t/dns-challenge-is-in-staging/8322 for the current state of dns-01 support.
You need a hook script that deploys the challenge to your DNS server!