PowerShell Script To Configure NetScaler SSL for “A+ Score” At Qualys SSL Labs

Almost a year ago I wrote a post regarding SSL hardening on Netscaler.
Now, Techdrabble guys did a great job in converting a similar configuration using a “Powershell script” to configure Netscaler SSL hardening on any NS 11.x release.

The script does the following:

• Checks and sets all SSL Netscaler managment, load balancer, Netscaler Gateway and content switch VIPS
• Enables TLS 1.2
• Disables SSLv2 and SSLv3
• Removes “Default” ciphers
• Creates new cipher group and binds to VIPs while removing all other ciphers (auto detects VPX with corresponding supported ciphers)
• Creates and binds Diffie-Hellman (DH) 2048 bit key (Forward Secrecy)
• Creates and binds “Strict Transport Security policy”
• Allow secure renegotiation
• Results in A+ on ssllabs

A Special Thanx to Techdrabble and Carl Stalhood for this 🙂

Download PowerShell Script Netscaler SSL Hardening

Or if you prefer to copy and paste the code, here you go!

<#
.SYNOPSIS
A PowerShell script for hardening Netscaler SSL IPs
.DESCRIPTION
A PowerShell script that enables TLS 1.2, disables SSLv2 and SSLv3, creates and binds Diffie-Hellman (DH) key, creates and binds “Strict Transport Security policy” and removes all other ciphers and binds cipher group mentioned in https://www.citrix.com/blogs/2015/05/22/scoring-an-a-at-ssllabs-com-with-citrix-netscaler-the-sequel/
.PARAMETER nsip
DNS Name or IP of the Netscaler that needs to be configured. (MANDATORY)
.PARAMETER adminaccount
Netscaler admin account (Default: nsroot)
.PARAMETER adminpassword
Password for the Netscaler admin account (Default: nsroot)
.PARAMETER https
Use HTTPS for communication
.PARAMETER ciphergroupname
Cipher group name to search for (Default: “custom-ssllabs-cipher”)
.PARAMETER rwactname
ReWrite action name (Default: “act-sts-header”)
.PARAMETER rwpolname
ReWrite policy name (Default: “pol-sts-force”)
.PARAMETER dhname
DH Key to be used (Default: “dhkey2048.key”)
.PARAMETER mgmt
Perform changes on Netsclaer managment IP
.PARAMETER nolb
Do not perform changes on Netscaler Load Balanced SSL VIPs
.PARAMETER nocsw
Do not perform changes on Netscaler Content Switch VIPs
.PARAMETER novpn
Do not perofm change on Netscaler VPN\Netscaler Gateway VIPs
.PARAMETER noneg
Do not adjust SSL renegotiation
.EXAMPLE
./set-nsssl -nsip 10.1.1.2
.EXAMPLE
./set-nsssl -nsip 10.1.1.2 -https
.EXAMPLE
./set-nsssl -nsip 10.1.1.2 -adminaccount nsadmin -adminpassword “mysupersecretpassword” -ciphergroupname “mynewciphers” -rwactname “rw-actionnew” -rwpolname “rw-polnamenew” -dhname “mydhey.key” -mgmt -nocsw
#>

 

Param
(
[Parameter(Mandatory=$true)]$nsip,
[String]$adminaccount=”nsroot”,
[String]$adminpassword=”nsroot”,
[switch]$https,
[string]$ciphergroupname = “custom-ssllabs-cipher”,
[string]$rwactname = “act-sts-header”,
[string]$rwpolname = “pol-sts-force”,
[string]$dhname = “dhkey2048.key”,
[switch]$mgmt,
[switch]$nolb,
[switch]$nocsw,
[switch]$novpn,
[switch]$noneg

)

 

#Netscaler NSIP login information
if ($https)
{
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls
[System.Net.ServicePointManager]::ServerCertificateValidationCallback = {$true}
write-host “Connecting HTTPS” -ForegroundColor Yellow
$hostname = “https://” + $nsip
}
else
{
write-host “Connecting HTTP” -ForegroundColor Yellow
$hostname = “http://” + $nsip
}

$username = $adminaccount
$password = $adminpassword

 

Functions
###############################
#Probably not much you have to edit below this
###############################

 

function Login {

# Login to NetScaler and save session to global variable
$body = ConvertTo-JSON @{
“login”=@{
“username”=”$username”;
“password”=”$password”
}
}
try {
Invoke-RestMethod -uri “$hostname/nitro/v1/config/login” -body $body -SessionVariable NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.login+json”} -Method POST|Out-Null
$Script:NSSession = $local:NSSession
}
Catch
{
throw $_
}
}

 

function Cipher ($Name, $Cipher) {

# Support function called by CipherGroup
$body = @{
“sslcipher_binding”=[ordered]@{
“ciphergroupname”=”$Name”;
“ciphername”=”$Cipher”;
}
}
$body = ConvertTo-JSON $body
Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslcipher_binding/$Name” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.sslcipher_binding+json”} -Method PUT|Out-Null
}

 

function get-ciphers ($Name) {
#Get cipher groups already on netscaler
$ciphers = Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslcipher” -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method GET
return $ciphers.sslcipher
}

 

function CipherGroup ($Name) {
#Ciphers from https://www.citrix.com/blogs/2015/05/22/scoring-an-a-at-ssllabs-com-with-citrix-netscaler-the-sequel/
$body = @{
“sslcipher”=@{
“ciphergroupname”=”$Name”;
}
}
$body = ConvertTo-JSON $body
Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslcipher?action=add” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.sslcipher+json”} -Method POST|Out-Null
#feel free to edit these
Cipher $Name TLS1.2-ECDHE-RSA-AES256-GCM-SHA384
Cipher $Name TLS1.2-ECDHE-RSA-AES128-GCM-SHA256
Cipher $Name TLS1.2-ECDHE-RSA-AES-256-SHA384
Cipher $Name TLS1.2-ECDHE-RSA-AES-128-SHA256
Cipher $Name TLS1-ECDHE-RSA-AES256-SHA
Cipher $Name TLS1-ECDHE-RSA-AES128-SHA
Cipher $Name TLS1.2-DHE-RSA-AES256-GCM-SHA384
Cipher $Name TLS1.2-DHE-RSA-AES128-GCM-SHA256
Cipher $Name TLS1-DHE-RSA-AES-256-CBC-SHA
Cipher $Name TLS1-DHE-RSA-AES-128-CBC-SHA
Cipher $Name TLS1-AES-256-CBC-SHA
Cipher $Name TLS1-AES-128-CBC-SHA
Cipher $Name SSL3-DES-CBC3-SHA
}

 

function CipherGroup-vpx ($Name) {
#Ciphers from https://www.citrix.com/blogs/2015/05/22/scoring-an-a-at-ssllabs-com-with-citrix-netscaler-the-sequel/
#for VPXs had to remove TLS1.2-ECDHE-RSA-AES-128-SHA256
$body = @{
“sslcipher”=@{
“ciphergroupname”=”$Name”;
}
}
$body = ConvertTo-JSON $body
Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslcipher?action=add” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.sslcipher+json”} -Method POST|Out-Null
#feel free to edit these
Cipher $Name TLS1.2-ECDHE-RSA-AES256-GCM-SHA384
Cipher $Name TLS1.2-ECDHE-RSA-AES128-GCM-SHA256
Cipher $Name TLS1.2-ECDHE-RSA-AES-256-SHA384
Cipher $Name TLS1.2-ECDHE-RSA-AES-128-SHA256
Cipher $Name TLS1-ECDHE-RSA-AES256-SHA
Cipher $Name TLS1-ECDHE-RSA-AES128-SHA
Cipher $Name TLS1.2-DHE-RSA-AES256-GCM-SHA384
Cipher $Name TLS1.2-DHE-RSA-AES128-GCM-SHA256
Cipher $Name TLS1-DHE-RSA-AES-256-CBC-SHA
Cipher $Name TLS1-DHE-RSA-AES-128-CBC-SHA
Cipher $Name TLS1-AES-256-CBC-SHA
Cipher $Name TLS1-AES-128-CBC-SHA
Cipher $Name SSL3-DES-CBC3-SHA
}

 

function get-vpnservers{
#gets netscaler gateway VIPs
$vips = Invoke-RestMethod -uri “$hostname/nitro/v1/config/vpnvserver” -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method GET
return $vips.vpnvserver
}

 

function get-vservers {
#gets load balancers
$vips = Invoke-RestMethod -uri “$hostname/nitro/v1/config/lbvserver” -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method GET
return $vips.lbvserver
}

 

function get-csservers {
#gets content switches
$vips = Invoke-RestMethod -uri “$hostname/nitro/v1/config/csvserver” -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method GET
return $vips.csvserver
}

 

function Logout {
#logs out
$body = ConvertTo-JSON @{
“logout”=@{
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/logout” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.logout+json”} -Method POST|Out-Null
}

 

function set-cipher ($Name, $cipher){

#unbinds all cipher groups
$foundflag = 0 #flag if cipher already found
$cgs = Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslvserver_sslciphersuite_binding/$Name” -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method GET

$cgs = $cgs.sslvserver_sslciphersuite_binding

foreach ($cg in $cgs)
{

if ($cg.ciphername -notlike $cipher)
{
write-host “Unbinding” $cg.ciphername -ForegroundColor yellow

Invoke-RestMethod -uri (“$hostname/nitro/v1/config/sslvserver_sslciphersuite_binding/$Name” + “?args=cipherName:” + $cg.ciphername ) -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.sslvserver_sslciphersuite_binding+json”} -Method DELETE|Out-Null
}
else
{
write-host $cipher “already present..” -ForegroundColor Green
$foundflag = 1
}

}

 

if ($foundflag -eq 0)
{
#binds new cipher group created if not already present
write-host “Binding $cipher” -ForegroundColor Yellow
$body = ConvertTo-JSON @{
“sslvserver_sslciphersuite_binding”=@{
“vservername”=”$Name”;
“ciphername”=”$Cipher”;
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslvserver_sslciphersuite_binding/$Name” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.sslvserver_sslciphersuite_binding+json”} -Method PUT|Out-Null
}

#disables sslv2 and sslv3
$body = ConvertTo-JSON @{
“sslvserver”=@{
“vservername”=”$Name”;
“tls12″=”ENABLED”;
“ssl3″=”DISABLED”;
“ssl2″=”DISABLED”;
“dh”=”ENABLED”;
“dhfile”= $dhname;
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslvserver/$Name” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.sslvserver+json”} -Method PUT|Out-Null

}

 

function set-nscipher ($Name, $cipher){

#unbinds all cipher groups
$foundflag = 0 #flag if cipher already found
$cgs = Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslservice_sslciphersuite_binding/$Name” -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method GET

$cgs = $cgs.sslservice_sslciphersuite_binding

foreach ($cg in $cgs)
{

if ($cg.ciphername -notlike $cipher)
{
write-host “Unbinding” $cg.ciphername -ForegroundColor yellow

Invoke-RestMethod -uri (“$hostname/nitro/v1/config/sslservice_sslciphersuite_binding/$Name” + “?args=cipherName:” + $cg.ciphername ) -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.sslservice_sslciphersuite_binding+json”} -Method DELETE|Out-Null
}
else
{
write-host $cipher “already present..” -ForegroundColor Green
$foundflag = 1
}

}

 

if ($foundflag -eq 0)
{
#binds new cipher group created if not already present
write-host “Binding $cipher” -ForegroundColor Yellow
$body = ConvertTo-JSON @{
“sslservice_sslciphersuite_binding”=@{
“servicename”=”$Name”;
“ciphername”=”$Cipher”;
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslservice_sslciphersuite_binding/$Name” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.sslservice_sslciphersuite_binding+json”} -Method PUT|Out-Null
}

}

function set-nsip {
#Adjusts SSL setting for IPV4 and IPV6 on 443
$services = Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslservice” -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method GET
$services = $services.sslservice

#only want nshttps services
$nsips = $services|where{($_.servicename -like “nshttps-*”) -or ($_.servicename -like “nskrpcs-*”) -or ($_.servicename -like “nsrpcs-*”) }
foreach ($nsip in $nsips)
{
$name = $nsip.servicename
write-host $name

#disables sslv2 and sslv3
$body = ConvertTo-JSON @{
“sslservice”=@{
“servicename”=”$Name”;
“tls12″=”ENABLED”;
“ssl3″=”DISABLED”;
“ssl2″=”DISABLED”;
“dh”=”ENABLED”;
“dhfile”= $dhname;
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslservice/$Name” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.sslservice+json”} -Method PUT|Out-Null
set-nscipher $name $ciphergroupname
}
}

function SaveConfig {
#Saves NS config
$body = ConvertTo-JSON @{
“nsconfig”=@{
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/nsconfig?action=save” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.nsconfig+json”} -Method POST|Out-Null
}

function get-rewritepol {
#gets rewrite policies
$pols = Invoke-RestMethod -uri “$hostname/nitro/v1/config/rewritepolicy” -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method GET
return $pols.rewritepolicy
}

function EnableFeature ($feature) {
#enables NS feature
$body = @{
“nsfeature”=@{
“feature”=$feature;
}
}
$body = ConvertTo-JSON $body
Invoke-RestMethod -uri “$hostname/nitro/v1/config/nsfeature?action=enable” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.nsfeature+json”} -Method POST|Out-Null
}

Function SetupSTS ($rwactname, $rwpolname) {

# Strict Transport Security Policy creation

EnableFeature Rewrite

$body = ConvertTo-JSON @{
“rewriteaction”=@{
“name”=$rwactname;
“type”=”insert_http_header”;
“target”=”Strict-Transport-Security”;
“stringbuilderexpr”='”max-age=157680000″‘;
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/rewriteaction?action=add” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.rewriteaction+json”} -Method POST|Out-Null

$body = ConvertTo-JSON @{
“rewritepolicy”=@{
“name”=$rwpolname;
“action”=$rwactname;
“rule”=’true’;
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/rewritepolicy?action=add” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.rewritepolicy+json”} -Method POST|Out-Null

}

Function set-lbpols ($vip, $rwpolname){
#binds LB policy
$name = $vip.name

$body = ConvertTo-JSON @{
“lbvserver_rewritepolicy_binding”=@{
“name”=$Name;
“policyname”=$rwpolname;
“priority”=100;
“bindpoint” = “RESPONSE”;
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/lbvserver_rewritepolicy_binding/$Name” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.lbvserver_rewritepolicy_binding+json”} -Method POST|Out-Null

}

Function set-cspols ($vip, $rwpolname){
#binds CS policy
$name = $vip.name

$body = ConvertTo-JSON @{
“csvserver_rewritepolicy_binding”=@{
“name”=$Name;
“policyname”=$rwpolname;
“priority”=100;
“bindpoint” = “RESPONSE”;
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/csvserver_rewritepolicy_binding/$Name” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.csvserver_rewritepolicy_binding+json”} -Method PUT|Out-Null

}

Function set-vpnpols ($vip, $rwpolname){
#binds NG policy
$name = $vip.name

$body = ConvertTo-JSON @{
“vpnvserver_rewritepolicy_binding”=@{
“name”=$Name;
“policy”=$rwpolname;
“priority”=100;
“gotopriorityexpression” = “END”;
“bindpoint” = “RESPONSE”;
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/vpnvserver_rewritepolicy_binding/$Name” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/vnd.com.citrix.netscaler.vpnvserver_rewritepolicy_binding+json”} -Method POST|Out-Null

}

function checkvpx {
#Checks if NS is a VPX or not
$info = Invoke-RestMethod -uri “$hostname/nitro/v1/config/nshardware” -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method GET
$info = $info.nshardware
if ($info.hwdescription -like “NetScaler Virtual Appliance”)
{
write-host “VPX FOUND…” -ForegroundColor Gray
$found = $true
}
else
{
$found = $false
}
Return $found
}

function new-dhkey ($name) {

#Creates new DH Key
$body = @{

“ssldhparam”= @{
“dhfile”= $name;
“bits”=”2048”;
“gen”=”2”;
}
}
try {
$body = ConvertTo-JSON $body
Invoke-RestMethod -uri “$hostname/nitro/v1/config/ssldhparam?action=create” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method POST -TimeoutSec 240
}
Catch
{
$ErrorMessage = $_.Exception.Response
$FailedItem = $_.Exception.ItemName
}
if ($ErrorMessage.Response.StatusCode -like “Conflict”)
{
write-host $name “already present” -ForegroundColor Green
}

}

function checkfordhkey ($dhname) {
#Checks if DHKEY is present
$urlstring = “$hostname” + “/nitro/v1/config/systemfile/” + $dhname + “?args=filelocation:%2Fnsconfig%2Fssl”
try {
$info = Invoke-RestMethod -uri $urlstring -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method GET
$msg = $info.message
}
Catch
{
$ErrorMessage = $_.Exception.Response
$FailedItem = $_.Exception.ItemName
}
if ($msg -like “Done”)
{
write-host “DHKEY alredy present…” -ForegroundColor Green
$found = $true
}
else
{
write-host “DHKEY NOT present…” -ForegroundColor Yellow
$found = $false
}
Return $found
}

Function set-sslparams {
#Allow secure renegotiation

$body = ConvertTo-JSON @{
“sslparameter”=@{
“denysslreneg”=”FRONTEND_CLIENT”;
}
}
Invoke-RestMethod -uri “$hostname/nitro/v1/config/sslparameter/” -body $body -WebSession $NSSession `
-Headers @{“Content-Type”=”application/json”} -Method PUT|Out-Null

}

###Script starts here

#Logs into netscaler
write-host “Logging in…”
Login

write-host “Checking for DHKEY: ” $dhname  -ForegroundColor White
#Checks for and creates DH key
if ((checkfordhkey $dhname) -eq $false)
{
write-host “DHKEY creation in process.  Can take a couple of minutes…” -ForegroundColor yellow
new-dhkey $dhname
}

write-host “Checking for cipher group…” -ForegroundColor White
#Checks for cipher group we will be creating
if (((get-ciphers).ciphergroupname) -notcontains $ciphergroupname)
{
write-host “Creating” $ciphergroupname -ForegroundColor Gray
if (checkvpx)
{
write-host “Creating cipher group for VPX…”
CipherGroup-vpx $ciphergroupname
}
else
{
write-host “Creating cipher group for NON-VPX…”
ciphergroup $ciphergroupname
}
}
else
{
write-host $ciphergroupname “already present” -ForegroundColor Green
}

write-host “Checking for rewrite policy…” -ForegroundColor White
#Checks for rewrite policy
if (((get-rewritepol).name) -notcontains $rwpolname)
{
write-host “Creating ” $rwpolname -ForegroundColor Gray
SetupSTS $rwactname $rwpolname
}
else
{
write-host $rwpolname “already present” -ForegroundColor Green
}

if ($mgmt)
{
write-host “Adjusting SSL managment IPs…” -ForegroundColor White
#adjusts all managment IPs.  Does not adjust ciphers
set-nsip

}
else
{
write-host “Skipping SSL managment IPs…”
}

if($nolb)
{
write-host “Skipping LB VIPs…” -ForegroundColor White
}
else
{
write-host “Checking LB VIPs…” -ForegroundColor White
#Gets all LB servers that are SSL and makes changes
$lbservers = (get-vservers)
$ssls = $lbservers|where{$_.servicetype -like “SSL”}

foreach ($ssl in $ssls){
write-host $ssl.name
(set-cipher $ssl.name $ciphergroupname)
(set-lbpols $ssl $rwpolname).message
}
}

if($novpn)
{
write-host “Skiping VPN VIPS…”
}
else
{
write-host “Checking VPN VIPs…” -ForegroundColor White
#Gets all Netscaler Gateways and makes changes
$vpnservers = get-vpnservers

foreach ($ssl in $vpnservers){
write-host $ssl.name
(set-cipher $ssl.name $ciphergroupname)
(set-vpnpols $ssl $rwpolname).message
}
}

if($nocsw)
{
write-host “Skipping CSW IPs…” -ForegroundColor White
}
else
{
write-host “Checking CS VIPs…” -ForegroundColor White
#Gets all Content Switches and makes changes
$csservers = get-csservers
#Filters for only SSL
$csssls = $csservers|where{$_.servicetype -like “SSL”}
foreach ($sslcs in $csssls){
write-host $sslcs.name
(set-cipher $sslcs.name $ciphergroupname)
(set-cspols $sslcs $rwpolname).message
}
}

if($noneg)
{
write-host “Skipping SSL renegotiation…” -ForegroundColor White
}
else
{
write-host “Setting SSL renegotiation…”  -ForegroundColor White
set-sslparams
}

write-host “Saving NS config..” -ForegroundColor White
#Save NS Config
SaveConfig

write-host “Logging out…” -ForegroundColor White
#Logout
Logout