#Requires -Version 5.1
<#
    JbTecWiz Support Centre -- generated fix script

    Fault : CRYPT_E_REVOCATION_OFFLINE -- the revocation function could not check revocation
    Fix   : Republish the CRL and fix the distribution point
    Source: https://jbtecwiz.com/support/srv-cert-revocation

    Run as     : Elevated PowerShell on the CA
    Expect     : 30 minutes
    Risk       : low
    Reversible : yes

    WHEN THIS IS THE RIGHT FIX
    An internal AD CS certificate. The most common cause by far is simply an
    expired CRL.

    HOW TO UNDO IT
    None -- publishing a CRL is additive.

    This script walks the fix one step at a time and asks before each
    one. Steps with no command are things you do yourself -- it prints
    those and waits. Run with -DryRun to print without executing.

    --------------------------------------------------------------------
    NO WARRANTY - USE AT YOUR OWN RISK

    This script is provided by JbTecWiz as-is and with no warranty of any
    kind, express or implied. You run it entirely at your own risk.

    JbTecWiz accepts no liability for any loss or damage arising from its
    use, including but not limited to data loss, downtime, or configuration
    changes that turn out to be wrong for your system.

    You are responsible for reading this script before running it, for
    satisfying yourself that it suits the machine in front of you, and for
    having a working backup first. Some steps cannot be undone.
    --------------------------------------------------------------------
#>

[CmdletBinding()]
param(
    # Print every step and command without running anything.
    [switch]$DryRun,
    # Do not ask before each step. Read the script first if you use this.
    [switch]$Unattended
)

$ErrorActionPreference = 'Stop'
$script:Failed = 0

# - THIS SCRIPT WILL NOT RUN UNTIL YOU EDIT IT -
# The commands below contain values only you can supply. Search the
# script for each one, replace it, then delete this block.
$script:MustEdit = @(
    'C:\path\to\cert.cer'   # a placeholder file path
)
if ($script:MustEdit.Count) {
    Write-Host ""
    Write-Host '  This script needs editing before it can run.' -ForegroundColor Yellow
    Write-Host '  Replace each of these with a real value:' -ForegroundColor Yellow
    $script:MustEdit | ForEach-Object { Write-Host ("    " + $_) -ForegroundColor Yellow }
    Write-Host ""
    Write-Host '  Then delete the $script:MustEdit block near the top.'
    Write-Host ""
    exit 2
}

function Write-Rule { param([string]$Text)
    Write-Host ''
    Write-Host ('-' * 70) -ForegroundColor DarkGray
    if ($Text) { Write-Host $Text -ForegroundColor Cyan }
}

function Show-Prose { param([string]$Text, [string]$Colour = "Gray")
    if (-not $Text) { return }
    $words = $Text -split "\s+"; $line = "  "
    foreach ($w in $words) {
        if (($line.Length + $w.Length) -gt 74) { Write-Host $line -ForegroundColor $Colour; $line = "  " }
        $line += "$w "
    }
    if ($line.Trim()) { Write-Host $line -ForegroundColor $Colour }
}

function Invoke-Step {
    param(
        [int]$Number, [string]$Do, [string]$Why,
        [scriptblock]$Command, [switch]$Manual, [string]$Shell = "powershell"
    )
    Write-Rule "  Step $Number of 5"
    Show-Prose $Do "White"
    if ($Why) { Write-Host ""; Show-Prose $Why "DarkGray" }

    if ($Manual) {
        Write-Host ''
        Write-Host '  -> Do this yourself, then press Enter to carry on.' -ForegroundColor Yellow
        if (-not $Unattended -and -not $DryRun) { [void](Read-Host) }
        return
    }

    Write-Host ''
    foreach ($l in ($Command.ToString().Trim() -split "`n")) {
        Write-Host ("    " + $l.Trim()) -ForegroundColor Green
    }
    Write-Host ''

    if ($DryRun) { Write-Host "  (dry run -- not executed)" -ForegroundColor DarkGray; return }
    if (-not $Unattended) {
        $a = Read-Host "  Run this step? [Y]es / [S]kip / [Q]uit"
        if ($a -match "^[Qq]") { Write-Host "  Stopped at your request."; exit 0 }
        if ($a -match "^[Ss]") { Write-Host "  Skipped." -ForegroundColor DarkGray; return }
    }
    try { & $Command }
    catch {
        $script:Failed++
        Write-Host ("  Step $Number failed: " + $_.Exception.Message) -ForegroundColor Red
        Show-Prose "The rest of the fix may depend on this. Read the write-up before carrying on." "Red"
        if (-not $Unattended) {
            $c = Read-Host "  Carry on anyway? [y/N]"
            if ($c -notmatch "^[Yy]") { exit 1 }
        }
    }
}

Write-Rule
Write-Host '  CRYPT_E_REVOCATION_OFFLINE -- the revocation function could not check revocation' -ForegroundColor White
Write-Host '  Republish the CRL and fix the distribution point' -ForegroundColor Cyan
Write-Host ''
Write-Host '  Risk: low   Reversible   30 minutes'
Write-Host ''
Show-Prose 'No warranty. Use at your own risk - JbTecWiz accepts no liability. Read it before you run it, and have a backup.' 'DarkYellow'
Write-Rule

if (-not $Unattended -and -not $DryRun) {
    $go = Read-Host '  Ready? [y/N]'
    if ($go -notmatch "^[Yy]") { Write-Host "  Nothing was changed."; exit 0 }
}

Invoke-Step -Number 1 -Do 'On the failing machine, read what the certificate says its CDP is, and test it.' -Why 'The URL Retrieval Tool tests every CDP and OCSP URL in the chain and shows exactly which one fails, which saves guessing.' -Command {
    cmd.exe /c 'certutil -URL C:\path\to\cert.cer'
}

Invoke-Step -Number 2 -Do 'On the CA, check when the CRL expires.' -Command {
    cmd.exe /c 'certutil -getreg CA\CRLPeriod & certutil -getreg CA\CRLPeriodUnits & certutil -CRL'
}

Invoke-Step -Number 3 -Do 'Publish a fresh CRL.' -Command {
    cmd.exe /c 'certutil -CRL'
}

Invoke-Step -Number 4 -Do 'Copy it to every location listed as a CDP -- an HTTP path is the one that matters for non-domain clients.' -Manual

Invoke-Step -Number 5 -Do 'Verify the chain now builds on the failing machine.' -Command {
    cmd.exe /c 'certutil -verify -urlfetch C:\path\to\cert.cer'
}

Write-Rule "  Confirm it worked"
Show-Prose 'certutil -verify -urlfetch reports the revocation check succeeded.' 'White'

Write-Rule
if ($script:Failed -gt 0) {
    Write-Host ("  Finished with " + $script:Failed + " failed step(s).") -ForegroundColor Yellow
    Show-Prose 'Read the full write-up at https://jbtecwiz.com/support/srv-cert-revocation' 'Yellow'
} else {
    Write-Host '  Finished.' -ForegroundColor Green
}
Write-Host ''
Show-Prose 'To undo: None -- publishing a CRL is additive.' 'DarkGray'
Write-Rule