(PowerShell) RSA Signature using Private Key from .snk File

See more RSA Examples

A .snk file (Strong Name Key file) is a file format used in the .NET ecosystem to store an RSA public/private key pair. This key pair is typically used for strong-naming assemblies, which is a process of signing .NET assemblies to ensure their integrity and to uniquely identify them.

This example loads a private key from a .snk file and creates an RSA signature.

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Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$rsa = New-Object Chilkat.Rsa

# Load the .snk and return the private key as XML.
$xmlStr = $rsa.SnkToXml("./test.snk")
if ($rsa.LastMethodSuccess -eq $false) {
    $($rsa.LastErrorText)
    exit
}

$success = $rsa.ImportPrivateKey($xmlStr)
if ($success -eq $false) {
    $($rsa.LastErrorText)
    exit
}

# Sign the SHA-256 hash of the utf-8 byte representation of the contents of sb
# Return the signature in base64 format.
$rsa.EncodingMode = "base64"
$rsa.Charset = "utf-8"
$sigBase64 = $rsa.SignStringENC("This is the text to be hashed and signed.","sha256")
if ($rsa.LastMethodSuccess -eq $false) {
    $($rsa.LastErrorText)
    exit
}

$("RSA signature as base64: " + $sigBase64)