Add one-time NinjaOne installation script

scripts/install-ocsentinel-ninja-once.ps1

@@ -0,0 +1,70 @@
+[CmdletBinding()]
+param(
+    [string]$ManifestUrl = "https://gitea.officecom.cloud/officecom/oc-sentinel/raw/main/release/stable/version.json",
+    [string]$WebhookUrl = "",
+    [string]$SecretValue = ""
+)
+
+$ErrorActionPreference = "Stop"
+$ProgressPreference = "SilentlyContinue"
+[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
+
+function Get-NinjaValue {
+    param([Parameter(Mandatory)][string]$Name)
+
+    $value = [Environment]::GetEnvironmentVariable($Name, "Process")
+    return if ($null -eq $value) { "" } else { $value.Trim() }
+}
+
+if ([string]::IsNullOrWhiteSpace($WebhookUrl)) { $WebhookUrl = Get-NinjaValue -Name "webhookurl" }
+if ([string]::IsNullOrWhiteSpace($SecretValue)) { $SecretValue = Get-NinjaValue -Name "secretvalue" }
+if ([string]::IsNullOrWhiteSpace($WebhookUrl) -or [string]::IsNullOrWhiteSpace($SecretValue)) {
+    throw "WebhookUrl and SecretValue must be set as NinjaOne script variables."
+}
+
+$manifest = Invoke-RestMethod -Method Get -Uri $ManifestUrl -TimeoutSec 60
+if ([string]::IsNullOrWhiteSpace($manifest.artifactUrl) -or [string]::IsNullOrWhiteSpace($manifest.sha256)) {
+    throw "The release manifest is incomplete."
+}
+
+$downloadRoot = Join-Path $env:ProgramData ("OCSentinel\\install-" + [Guid]::NewGuid().ToString("N"))
+$zipPath = Join-Path $downloadRoot "OCSentinelClient.zip"
+$extractPath = Join-Path $downloadRoot "payload"
+
+try {
+    New-Item -ItemType Directory -Force -Path $extractPath | Out-Null
+    Write-Host "Downloading OCSentinel $($manifest.version)."
+    Invoke-WebRequest -Uri $manifest.artifactUrl -OutFile $zipPath -TimeoutSec 300
+    $actualHash = (Get-FileHash -LiteralPath $zipPath -Algorithm SHA256).Hash.ToLowerInvariant()
+    if ($actualHash -ne ([string]$manifest.sha256).ToLowerInvariant()) {
+        throw "Release package SHA-256 validation failed."
+    }
+
+    Expand-Archive -LiteralPath $zipPath -DestinationPath $extractPath -Force
+    $installer = Get-ChildItem -Path $extractPath -Recurse -Filter "install-ocsentinel.ps1" | Select-Object -First 1
+    if ($null -eq $installer) { throw "The release package does not contain the installer." }
+
+    & powershell.exe -NoProfile -ExecutionPolicy Bypass -File $installer.FullName
+    if ($LASTEXITCODE -ne 0) { throw "Installer failed with code $LASTEXITCODE" }
+}
+finally {
+    if (Test-Path -LiteralPath $downloadRoot) { Remove-Item -LiteralPath $downloadRoot -Recurse -Force }
+}
+
+$installRoot = Join-Path $env:ProgramFiles "OCSentinel"
+$configPath = Join-Path $installRoot "config\ocsentinel-client.json"
+$secretScript = Join-Path $installRoot "scripts\protect-ocsentinel-secret.ps1"
+$monitorScript = Join-Path $installRoot "scripts\run-ocsentinel-monitor.ps1"
+$secretPath = "C:\ProgramData\OCSentinel\secrets\ocsentinel-upload-secret.dat"
+
+$config = Get-Content -LiteralPath $configPath -Raw | ConvertFrom-Json
+$config.n8nWebhookUrl = $WebhookUrl
+$config.environment = "production"
+$config | ConvertTo-Json -Depth 10 | Set-Content -LiteralPath $configPath -Encoding UTF8
+
+& powershell.exe -NoProfile -ExecutionPolicy Bypass -File $secretScript -SecretValue $SecretValue
+if ($LASTEXITCODE -ne 0) { throw "Writing the protected upload secret failed with code $LASTEXITCODE" }
+
+Write-Host "Running initial signed scan and upload."
+& powershell.exe -NoProfile -ExecutionPolicy Bypass -File $monitorScript -Mode status -ClientConfigPath $configPath -SecretPath $secretPath -UploadMode required
+exit $LASTEXITCODE