Let's Encrypt RouterOS / Mikrotik

Let's Encrypt certificates for RouterOS / Mikrotik

UPD 2018-05-27: Works with wildcard Let's Encrypt Domains

UPD 2019-07-11: Works with OpenSSH 7+

How it works:

• Dedicated Linux renew and push certificates to RouterOS / Mikrotik
• After CertBot renew your certificates
• The script connects to RouterOS / Mikrotik using RSA Key (without password or user input)
• Delete previous certificate files
• Delete the previous certificate
• Upload two new files: Certificate and Key
• Import Certificate and Key
• Change SSTP Server Settings to use new certificate
• Change WWW-SSL Service to use new certificate
• Change API-SSL Service to use new certificate
• Delete certificate and key files from RouterOS / Mikrotik storage

Installation on Ubuntu 16.04

Similar way you can use on Debian/CentOS/AMI Linux/Arch/Others

Download the repo to your system

sudo -s
cd /opt
git clone https://github.com/gitpel/letsencrypt-routeros

Edit the settings file:

vim /opt/letsencrypt-routeros/letsencrypt-routeros.settings

Variable Name	Value	Description
ROUTEROS_USER	admin	user with admin rights to connect to RouterOS
ROUTEROS_HOST	10.0.254.254	RouterOS\Mikrotik IP
ROUTEROS_SSH_PORT	22	RouterOS\Mikrotik PORT
ROUTEROS_PRIVATE_KEY	/opt/letsencrypt-routeros/id_rsa	Private RSA Key to connect to RouterOS
DOMAIN	mydomain.com	Use main domain for wildcard certificate or subdomain for subdomain certificate
SETUP_SERVICES	(SSTP WWW API)	Array of services for which certificate will be installed
SSH_STRICT_KEY_CHECKING	yes	Allows to override SSH option StrictHostKeyChecking

Change permissions:

chmod +x /opt/letsencrypt-routeros/letsencrypt-routeros.sh

Generate RSA Key for RouterOS

Make sure to leave the passphrase blank (-N "")

ssh-keygen -t rsa -f /opt/letsencrypt-routeros/id_rsa -N ""

Send Generated RSA Key to RouterOS / Mikrotik

source /opt/letsencrypt-routeros/letsencrypt-routeros.settings
scp -P $ROUTEROS_SSH_PORT /opt/letsencrypt-routeros/id_rsa.pub "$ROUTEROS_USER"@"$ROUTEROS_HOST":"id_rsa.pub" 

Setup RouterOS / Mikrotik side

Check that user is the same as in the settings file letsencrypt-routeros.settings

Check Mikrotik ssh port in /ip services ssh

Check Mikrotik firewall to accept on SSH port

:put "Enable SSH"
/ip service enable ssh

:put "Add to the user RSA Public Key"
/user ssh-keys import user=admin public-key-file=id_rsa.pub

CertBot Let's Encrypt

Install CertBot using official manuals https://certbot.eff.org/#ubuntuxenial-other

for Ubuntu 16.04

apt update
apt install software-properties-common -y
add-apt-repository ppa:certbot/certbot
apt update
apt install certbot -y

In the first time, you will need to create Certificates manually and put domain TXT record

follow CertBot instructions

source /opt/letsencrypt-routeros/letsencrypt-routeros.settings
certbot certonly --preferred-challenges=dns --manual -d $DOMAIN --manual-public-ip-logging-ok

Usage of the script

To use settings from the settings file:

/opt/letsencrypt-routeros/letsencrypt-routeros.sh -c letsencrypt-routeros.settings

To use script without settings file:

/opt/letsencrypt-routeros/letsencrypt-routeros.sh -u [RouterOS User] -h [RouterOS Host] -p [SSH Port] -k [SSH Private Key] -d [Domain]

To use script with CertBot hooks for wildcard domain:

certbot certonly --preferred-challenges=dns --manual -d *.$DOMAIN --manual-public-ip-logging-ok --post-hook /opt/letsencrypt-routeros/letsencrypt-routeros.sh --server https://acme-v02.api.letsencrypt.org/directory

To use script with CertBot hooks for subdomain:

certbot certonly --preferred-challenges=dns --manual -d $DOMAIN --manual-public-ip-logging-ok --post-hook /opt/letsencrypt-routeros/letsencrypt-routeros.sh

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License MIT

Copyright 2018 Konstantin Gimpel

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.