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Embed certs into Windows deployment scripts (#840)

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- Obviate need to copy separate script and certificate files
- Allow execution from any directory, not just the script's parent
  directory (no assumption of any particular working directory)
- Fix docs that neglected to mention copying cacert.pem
- Fix docs that incorrectly referred to the user cert store

As part of this work, rewrite the windows_client.ps1.j2 deployment
script template

- Add comment-based help
- Require admin privileges
- Use a Param() block
- Use parameter sets with -Add and -Remove switches
- Add the -GetInstalledCerts switch, to list any Algo certificates
  installed the machine's cert store
- Add the -SaveCerts switch, to save the embedded certificates to files
- Put Jinja2 variables inside Powershell variables,
- Use native Powershell cmdlets rather than shell out to certutil.exe
- Add a playbook to regenerate the windows_USER.ps1 scripts
pull/852/head^2
Micah R Ledbetter 6 years ago committed by Dan Guido
parent a8784bc0f4
commit e944ee993a
5 changed files with 319 additions and 29 deletions
Show Stats Download Patch File Download Diff File

4
README.md
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@ -101,9 +101,9 @@ No version of Android supports IKEv2. Install the [strongSwan VPN Client for And
### Windows 10
Copy your PowerShell script `windows_{username}.ps1` and p12 certificate `{username}.p12` to the Windows client and run the following command as Administrator to configure the VPN connection.
Copy your PowerShell script `windows_{username}.ps1` to the Windows client and run the following command as Administrator to configure the VPN connection.
```
powershell -ExecutionPolicy ByPass -File windows_{username}.ps1 Add
powershell -ExecutionPolicy ByPass -File windows_{username}.ps1 -Add
```
For a manual installation, see the [Windows setup instructions](/docs/client-windows.md).

66
docs/client-windows.md
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@ -1,27 +1,69 @@
# Windows client manual setup
Windows clients have a more complicated setup than most others. Follow the steps below to set one up:
## Automatic installtion
1. Copy the CA certificate (`cacert.pem`), user certificate (`$user.p12`), and the user PowerShell script (`windows_$user.ps1`) to the client computer.
2. Import the CA certificate to the local machine Trusted Root certificate store.
3. Open PowerShell as Administrator. Navigate to your copied files.
4. If you haven't already, you will need to change the Execution Policy to allow unsigned scripts to run.
To install automatically, use the generated user Powershell script.
1. Copy the user PowerShell script (`windows_USER.ps1`) to the client computer.
2. Open Powershell as Administrator.
3. Run the following command:
```powershell
Set-ExecutionPolicy Unrestricted -Scope CurrentUser
powershell -ExecutionPolicy ByPass -File C:\path\to\windows_USER.ps1 -Add
```
4. The command has help information available. To view its full help, run this from Powershell:
```powershell
Get-Help -Name .\windows_USER.ps1 -Full | more
```
5. In the same PowerShell window, run the included PowerShell script to import the user certificate, set up a VPN connection, and activate stronger ciphers on it.
6. After you execute the user script, set the Execution Policy back before you close the PowerShell window.
## Manual installation
1. Copy the CA certificate (`cacert.pem`) and user certificate (`USER.p12`) to the client computer
2. Open PowerShell as Administrator. Navigate to your copied files.
3. If you haven't already, you will need to change the Execution Policy to allow unsigned scripts to run.
```powershell
Set-ExecutionPolicy Restricted -Scope CurrentUser
Set-ExecutionPolicy Unrestricted -Scope CurrentUser
```
Your VPN is now installed and ready to use.
4. In the same window, run the necessary commands to install the certificates and create the VPN configuration. Note the lines at the top defining the VPN address, USER.p12 file location, and CA certificate location - change those lines to the IP address of your Algo server and the location you saved those two files. Also note that it will prompt for the "User p12 password", which is printed at the end of a successful Algo deployment.
```powershell
$VpnServerAddress = "1.2.3.4"
$UserP12Path = "$Home\Downloads\USER.p12"
$CaCertPath = "$Home\Downloads\cacert.pem"
$VpnName = "Algo VPN $VpnServerAddress IKEv2"
$p12Pass = Read-Host -AsSecureString -Prompt "User p12 password"
If you want to perform these steps by hand, you will need to import the user certificate to the Personal certificate store, add an IKEv2 connection in the network settings, then activate stronger ciphers on it via the following PowerShell script:
Import-PfxCertificate -FilePath $UserP12Path -CertStoreLocation Cert:\LocalMachine\My -Password $p12Pass
Import-Certificate -FilePath $CaCertPath -CertStoreLocation Cert:\LocalMachine\Root
$addVpnParams = @{
Name = $VpnName
ServerAddress = $VpnServerAddress
TunnelType = "IKEv2"
AuthenticationMethod = "MachineCertificate"
EncryptionLevel = "Required"
}
Add-VpnConnection @addVpnParams
$setVpnParams = @{
ConnectionName = $VpnName
AuthenticationTransformConstants = "GCMAES128"
CipherTransformConstants = "GCMAES128"
EncryptionMethod = "AES128"
IntegrityCheckMethod = "SHA384"
DHGroup = "ECP256"
PfsGroup = "ECP256"
Force = $true
}
Set-VpnConnectionIPsecConfiguration @setVpnParams
```
5. After you execute the user script, set the Execution Policy back before you close the PowerShell window.
```powershell
Set-VpnConnectionIPsecConfiguration -ConnectionName "Algo" -AuthenticationTransformConstants GCMAES128 -CipherTransformConstants GCMAES128 -EncryptionMethod AES128 -IntegrityCheckMethod SHA384 -DHGroup ECP256 -PfsGroup ECP256
Set-ExecutionPolicy Restricted -Scope CurrentUser
```
Your VPN is now installed and ready to use.

67
playbooks/win_script_rebuild.yml
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@ -0,0 +1,67 @@
---
# This playbook is designed to help when modifying the Windows script template
# in roles/vpn/templates/client_windows.ps1.j2
# It rebuilds the client_USER.ps1 scripts for each user defined in config.cfg,
# without redeploying users or opening an SSH connection to the Algo server at
# all.
#
# This playbook is _not_ part of a normal Algo deployment.
# It is only intended to speed up development of the client_USER.ps1 Windows
# Algo install scripts.
#
# REQUIREMENTS
# - Algo must have been deployed once
# - Windows users must have been enabled at deployment time
# - All users defined in config.cfg must not have changed
# - Only one Algo deployment exists in the configs/ directory
# - There must be exactly one subfolder in the configs/ directory:
# the folder named after the IP of the algo server
- hosts: localhost
gather_facts: False
tags: always
vars_files:
- ../config.cfg
tasks:
- name: Get config subdir
shell: find ../configs/* -maxdepth 0 -type d | sed 's/.*\///'
register: config_subdir_result
- fail:
msg:
- "Found wrong number of config subdirs... stdout:"
- "{{ config_subdir_result.split('\n') }}"
when: config_subdir_result.stdout.split('\n') | length != 1
- set_fact:
IP_subject_alt_name: "{{ config_subdir_result.stdout }}"
- debug:
var: IP_subject_alt_name
- name: Register p12 PayloadContent
shell: cat private/{{ item }}.p12 | base64
register: PayloadContent
args:
chdir: "../configs/{{ IP_subject_alt_name }}/pki/"
with_items: "{{ users }}"
- name: Set facts for mobileconfigs
set_fact:
proxy_enabled: false
PayloadContentCA: "{{ lookup('file' , '../configs/{{ IP_subject_alt_name }}/pki/cacert.pem')|b64encode }}"
- name: Build the windows client powershell script
template:
src: ../roles/vpn/templates/client_windows.ps1.j2
dest: ../configs/{{ IP_subject_alt_name }}/windows_{{ item.0 }}.ps1
mode: 0600
with_together:
- "{{ users }}"
- "{{ PayloadContent.results }}"
- name: List windows client powershell scripts
debug:
msg: "configs/{{ IP_subject_alt_name }}/windows_{{ item }}.ps1"
with_items:
- "{{ users }}"

6
roles/vpn/tasks/client_configs.yml
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@ -70,10 +70,12 @@
- name: Build the windows client powershell script
template:
src: client_windows.ps1.j2
dest: configs/{{ IP_subject_alt_name }}/windows_{{ item }}.ps1
dest: configs/{{ IP_subject_alt_name }}/windows_{{ item.0 }}.ps1
mode: 0600
when: Win10_Enabled is defined and Win10_Enabled == "Y" or supports_windows.stat.exists == true
with_items: "{{ users }}"
with_together:
- "{{ users }}"
- "{{ PayloadContent.results }}"
- name: Restrict permissions for the local private directories
file:

205
roles/vpn/templates/client_windows.ps1.j2
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@ -1,19 +1,198 @@
#Requires -RunAsAdministrator
function AddAlgoVPN {
certutil -f -importpfx .\{{ item }}.p12
certutil -addstore root .\cacert.pem
Add-VpnConnection -name "Algo VPN {{ IP_subject_alt_name }} IKEv2" -ServerAddress "{{ IP_subject_alt_name }}" -TunnelType IKEv2 -AuthenticationMethod MachineCertificate -EncryptionLevel Required
Set-VpnConnectionIPsecConfiguration -ConnectionName "Algo VPN {{ IP_subject_alt_name }} IKEv2" -AuthenticationTransformConstants GCMAES128 -CipherTransformConstants GCMAES128 -EncryptionMethod AES128 -IntegrityCheckMethod SHA384 -DHGroup ECP256 -PfsGroup ECP256 -Force
<#
.SYNOPSIS
Add or remove the Algo VPN
.DESCRIPTION
Add or remove the Algo VPN
See the examples for more information
.PARAMETER Add
Add the VPN to the local system
.PARAMETER Remove
Remove the VPN from the local system
.PARAMETER GetInstalledCerts
Retrieve Algo certs, if any, from the system certificate store
.PARAMETER SaveCerts
Save the Algo certs embedded in this file
.PARAMETER OutputDirectory
When saving the Algo certs, save to this directory
.PARAMETER Pkcs12DecryptionPassword
The decryption password for the user's PKCS12 certificate, sometimes called the "p12 password".
Note that this must be passed in as a SecureString, not a regular string.
You can create a secure string with the `Read-Host -AsSecureString` cmdlet.
See the examples for more information.
.EXAMPLE
client_USER.ps1 -Add
Adds the Algo VPN
.EXAMPLE
$p12pass = Read-Host -AsSecureString; client_USER.ps1 -Add -Pkcs12DecryptionPassword $p12pass
Create a variable containing the PKCS12 decryption password, then use it when adding the VPN.
This can be especially useful when troubleshooting, because you can use the same variable with
multiple calls to client_USER.ps1, rather than having to type the PKCS12 password each time.
.EXAMPLE
client_USER.ps1 -Remove
Removes the Algo VPN if installed.
.EXAMPLE
client_USER.ps1 -GetIntalledCerts
Show the Algo VPN's installed certificates, if any.
.EXAMPLE
client_USER.ps1 -SaveCerts -OutputDirectory $Home\Downloads
Save the embedded CA cert and encrypted user PKCS12 file.
#>
[CmdletBinding(DefaultParameterSetName="Add")] Param(
[Parameter(ParameterSetName="Add")]
[Switch] $Add,
[Parameter(ParameterSetName="Add")]
[SecureString] $Pkcs12DecryptionPassword,
[Parameter(Mandatory, ParameterSetName="Remove")]
[Switch] $Remove,
[Parameter(Mandatory, ParameterSetName="GetInstalledCerts")]
[Switch] $GetInstalledCerts,
[Parameter(Mandatory, ParameterSetName="SaveCerts")]
[Switch] $SaveCerts,
[Parameter(ParameterSetName="SaveCerts")]
[string] $OutputDirectory = "$PWD"
)
$ErrorActionPreference = "Stop"
$VpnServerAddress = "{{ IP_subject_alt_name }}"
$VpnName = "Algo VPN {{ IP_subject_alt_name }} IKEv2"
$VpnUser = "{{ item.0 }}"
$CaCertificateBase64 = "{{ PayloadContentCA }}"
$UserPkcs12Base64 = "{{ item.1.stdout }}"
if ($PsCmdlet.ParameterSetName -eq "Add" -and -not $Pkcs12DecryptionPassword) {
$Pkcs12DecryptionPassword = Read-Host -AsSecureString -Prompt "Pkcs12DecryptionPassword"
}
<#
.SYNOPSIS
Create a temporary directory
#>
function New-TemporaryDirectory {
[CmdletBinding()] Param()
do {
$guid = New-Guid | Select-Object -ExpandProperty Guid
$newTempDirPath = Join-Path -Path $env:TEMP -ChildPath $guid
} while (Test-Path -Path $newTempDirPath)
New-Item -ItemType Directory -Path $newTempDirPath
}
<#
.SYNOPSIS
Retrieve any installed Algo VPN certificates
#>
function Get-InstalledAlgoVpnCertificates {
[CmdletBinding()] Param()
Get-ChildItem -LiteralPath Cert:\LocalMachine\Root |
Where-Object {
$_.Subject -match "^CN=${VpnServerAddress}$" -and $_.Issuer -match "^CN=${VpnServerAddress}$"
}
Get-ChildItem -LiteralPath Cert:\LocalMachine\My |
Where-Object {
$_.Subject -match "^CN=${VpnUser}$" -and $_.Issuer -match "^CN=${VpnServerAddress}$"
}
}
function Save-AlgoVpnCertificates {
[CmdletBinding()] Param(
[String] $OutputDirectory = $PWD
)
$caCertPath = Join-Path -Path $OutputDirectory -ChildPath "cacert.pem"
$userP12Path = Join-Path -Path $OutputDirectory -ChildPath "$VpnUser.p12"
# NOTE: We cannot use ConvertFrom-Base64 here because it is not designed for binary data
[IO.File]::WriteAllBytes(
$caCertPath,
[Convert]::FromBase64String($CaCertificateBase64))
[IO.File]::WriteAllBytes(
$userP12Path,
[Convert]::FromBase64String($UserPkcs12Base64))
return New-Object -TypeName PSObject -Property @{
CaPem = $caCertPath
UserPkcs12 = $userP12Path
}
}
function Add-AlgoVPN {
[Cmdletbinding()] Param()
$workDir = New-TemporaryDirectory
try {
$certs = Save-AlgoVpnCertificates -OutputDirectory $workDir
$importPfxCertParams = @{
Password = $Pkcs12DecryptionPassword
FilePath = $certs.UserPkcs12
CertStoreLocation = "Cert:\LocalMachine\My"
}
Import-PfxCertificate @importPfxCertParams
$importCertParams = @{
FilePath = $certs.CaPem
CertStoreLocation = "Cert:\LocalMachine\Root"
}
Import-Certificate @importCertParams
} finally {
Remove-Item -Recurse -Force -LiteralPath $workDir
}
$addVpnParams = @{
Name = $VpnName
ServerAddress = $VpnServerAddress
TunnelType = "IKEv2"
AuthenticationMethod = "MachineCertificate"
EncryptionLevel = "Required"
}
Add-VpnConnection @addVpnParams
$setVpnParams = @{
ConnectionName = $VpnName
AuthenticationTransformConstants = "GCMAES128"
CipherTransformConstants = "GCMAES128"
EncryptionMethod = "AES128"
IntegrityCheckMethod = "SHA384"
DHGroup = "ECP256"
PfsGroup = "ECP256"
Force = $true
}
Set-VpnConnectionIPsecConfiguration @setVpnParams
}
function RemoveAlgoVPN {
Get-ChildItem cert:LocalMachine/Root | Where-Object { $_.Subject -match '^CN={{ IP_subject_alt_name }}$' -and $_.Issuer -match '^CN={{ IP_subject_alt_name }}$' } | Remove-Item
Get-ChildItem cert:LocalMachine/My | Where-Object { $_.Subject -match '^CN={{ item }}$' -and $_.Issuer -match '^CN={{ IP_subject_alt_name }}$' } | Remove-Item
Remove-VpnConnection -name "Algo VPN {{ IP_subject_alt_name }} IKEv2" -Force
function Remove-AlgoVPN {
[CmdletBinding()] Param()
Get-InstalledAlgoVpnCertificates | Remove-Item -Force
Remove-VpnConnection -Name $VpnName -Force
}
switch ($args[0]) {
"Add" { AddAlgoVPN }
"Remove" { RemoveAlgoVPN }
default { Write-Host Usage: $MyInvocation.MyCommand.Name "(Add|Remove)" }
switch ($PsCmdlet.ParameterSetName) {
"Add" { Add-AlgoVPN }
"Remove" { Remove-AlgoVPN }
"GetInstalledCerts" { Get-InstalledAlgoVpnCertificates }
"SaveCerts" {
$certs = Save-AlgoVpnCertificates -OutputDirectory $OutputDirectory
Get-Item -LiteralPath $certs.UserPkcs12, $certs.CaPem
}
default { throw "Unknown parameter set: '$($PsCmdlet.ParameterSetName)'" }
}

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