I’m sick of the “this doesn’t have a certificate” warnings. I:
- have a Windows 10 Pro machine
- want to use a LetsEncrypt certificate for RDP connections.
- don’t have an AD/IPA/whatever domain to join
- have the machine’s hostname in Cloudflare DNS
In this example I’ll use workstation.example.com
as the hostname I’ll connect to, change this for your own hostname.
- Install CertifyTheWeb.
- Copy this powershell script to somewhere you won’t delete it (eg.
c:\scripts\update_rdp_certificate.ps1
):
# this grabs the certificate thumbprint and tells RDP to use it
$HOSTNAME="workstation.example.com"
$THUMBPRINT = (ls Cert:\LocalMachine\my | WHERE {$_.Subject -match $HOSTNAME } | Select -First 1).Thumbprint
if (!$THUMBPRINT) {
write-host "Failed to find certificate thumbprint for ${HOSTNAME}, quitting."
} else {
write-host "Found certificate thumbprint for ${HOSTNAME}: ${THUMBPRINT}"
write-host "Configuring RDP"
& wmic /namespace:\\root\CIMV2\TerminalServices PATH Win32_TSGeneralSetting Set SSLCertificateSHA1Hash="$THUMBPRINT"
write-host `Done!`
}
- Open CertifyTheWeb.
- Register a contact for LetsEncrypt with some contact details under both the normal and
test
modes. Test mode is enabled by clicking on the advanced tab and ticking theUse staging Mode (Test Certificates)
box. - Click New Certificate.
- Select
Certificate
on the right if it’s not already selected. - In the
Domains
tab , enter the full hostname you’ll use to connect to the machine. ie.workstation.example.com
. Remember to click the green+
next to the domain name to add it to the list. - On the
Advanced
tab, set the Certificate Authority toLetsEncrypt
. Until you’re sure everything works, tick theUse staging Mode (Test Certificates)
box. - Click on Authorisation on the right.
- Change the
Challenge Type
todns-01
and the DNS Update Method toCloudflare DNS API
. - Add the a new Credential Cloudflare API token.
- You’ll need to give it permission to edit the DNS zone you want to issue certificates for.
- Select the Zone you want to issue the certificate under by clicking the
...
next to DNS Zone ID and selecting the zone name. - Click
Deployment
on the right. - Set the Deployment Mode to
Certificate Store Only
since we won’t be assigning this to any IIS Websites. - Click
Tasks
on the right and add a Deployment Task ofRun PowerShell Script
. - On the Task Parameters tab, set the Program/Script to the path of your script (eg.
c:\scripts\update_rdp_certificate.ps1
). - Click
Preview
on the right and check everything seems OK. - Click
Test
to make sure things work the way they should. - Click
Request certificate
and see how it works!
Remember to set the authority back to the production one and re-issue when you’re done. :)
[Read More]