Added check-credentials.ps1

scripts/check-credentials.ps1

@@ -0,0 +1,38 @@
+<#
+.SYNOPSIS
+	Checks credentials 
+.DESCRIPTION
+	This PowerShell script asks for credentials and checks them against saved ones ("$HOME\my.credentials" by default).
+.PARAMETER TargetFile
+	Specifies the target file ("$HOME\my.credentials" by default)
+.EXAMPLE
+	PS> ./check-credentials.ps1
+	Enter username and password, please.
+ 	✔️ Your credentials are correct.
+.LINK
+	https://github.com/fleschutz/PowerShell
+.NOTES
+	Author: Markus Fleschutz | License: CC0
+#>
+
+param([string]$TargetFile = "$HOME\my.credentials")
+
+try {
+	Write-Host "Enter username and password, please." -foreground red
+	$credsFromUser = Get-Credential
+
+	$secureString = Get-Content "$TargetFile" | ConvertTo-SecureString
+	$credsFromFile = New-Object System.Management.Automation.PSCredential($credsFromUser.UserName, $secureString)
+
+	if ($credsFromUser.UserName -ne $credsFromFile.UserName) { throw "Sorry, your username is wrong." }
+
+	$pw1 = [Runtime.InteropServices.Marshal]::PtrToStringAuto([Runtime.InteropServices.Marshal]::SecureStringToBSTR($credsFromUser.Password))
+	$pw2 = [Runtime.InteropServices.Marshal]::PtrToStringAuto([Runtime.InteropServices.Marshal]::SecureStringToBSTR($credsFromFile.Password))
+	if ($pw1 -cne $pw2) { throw "Sorry, your password is wrong." }
+
+	"✔️ Your credentials are correct."
+	exit 0 # success
+} catch {
+	"⚠️ Error in line $($_.InvocationInfo.ScriptLineNumber): $($Error[0])"
+	exit 1
+}