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Azure Key Vault Sign with a Certificate's Private Key

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Signs a hash using the private key of a certificate previously imported to an Azure Key Vault. AutoIt

Local $bSuccess = False

; This requires the Chilkat API to have been previously unlocked.
; See Global Unlock Sample for sample code.

; See Azure Key Vault Get Certificates for a more detailed explanation
; for how Chilkat is automatically getting the OAuth2 access token for your application.

; Provide information needed for Chilkat to automatically get an OAuth2 access token as needed.
$oJson = ObjCreate("Chilkat.JsonObject")
$oJson.UpdateString("client_id","APP_ID")
$oJson.UpdateString("client_secret","APP_PASSWORD")
$oJson.UpdateString("resource","https://vault.azure.net")
$oJson.UpdateString("token_endpoint","https://login.microsoftonline.com/TENANT_ID/oauth2/token")

; In this example, we'll sign the SHA256 hash of the string "This is a test"
$oSb = ObjCreate("Chilkat.StringBuilder")
Local $signedString = "This is a test"
$oSb.Append($signedString)
Local $sHash_base64url = $oSb.GetHash("sha256","base64url","utf-8")

; We're going to send a POST to the following URL:
; POST {vaultBaseUrl}/keys/{key-or-cert-name}/{key-or-cert-version}/sign?api-version=7.4

; For example:

; POST https://VAULT_NAME.vault.azure.net/keys/CERT_NAME/CERT_VERSION/sign?api-version=7.4
; 
; {
;   "alg": "RS512",
;   "value": "RUE3Nzg4NTQ4QjQ5RjFFN0U2NzAyQzhDNEMwMkJDOTA1MTYyOTUzNjI5NDhBNzZDQTlFOTM1NDA2M0ZGMjk2Mg"
; }

; The alg can be one of the following
; ES256  ECDSA using P-256 and SHA-256
; ES256K ECDSA using P-256K and SHA-256
; ES384  ECDSA using P-384 and SHA-384
; ES512  ECDSA using P-521 and SHA-512
; PS256  RSASSA-PSS using SHA-256 and MGF1 with SHA-256
; PS384  RSASSA-PSS using SHA-384 and MGF1 with SHA-384
; PS512  RSASSA-PSS using SHA-512 and MGF1 with SHA-512
; RS256  RSASSA-PKCS1-v1_5 using SHA-256
; RS384  RSASSA-PKCS1-v1_5 using SHA-384
; RS512  RSASSA-PKCS1-v1_5 using SHA-512

; The sample POST above uses SHA512.  We'll instead sign a SHA256 hash..

$oJsonBody = ObjCreate("Chilkat.JsonObject")
$oJsonBody.UpdateString("alg","RS256")
$oJsonBody.UpdateString("value",$sHash_base64url)

$oHttp = ObjCreate("Chilkat.Http")

; Instead of providing an actual access token, we give Chilkat the information that allows it to 
; automatically fetch the access token using the OAuth2 client credentials flow.
$oHttp.AuthToken = $oJson.Emit()

$oHttp.SetUrlVar("certName","importCert01")
$oHttp.SetUrlVar("certVersion","7140c8755ed14839b5d86a9f7e7f0497")
; Note: Replace "VAULT_NAME" with the name of your Azure key vault.
Local $sUrl = "https://VAULT_NAME.vault.azure.net/keys/{$certName}/{$certVersion}/sign?api-version=7.4"
$oResp = ObjCreate("Chilkat.HttpResponse")
$bSuccess = $oHttp.HttpJson("POST",$sUrl,$oJsonBody,"application/json",$oResp)
If ($bSuccess = False) Then
    ConsoleWrite($oHttp.LastErrorText & @CRLF)
    Exit
EndIf

Local $iStatusCode = $oResp.StatusCode

$oJsonResp = ObjCreate("Chilkat.JsonObject")
$oResp.GetBodyJson($oJsonResp)

$oJsonResp.EmitCompact = False
ConsoleWrite($oJsonResp.Emit() & @CRLF)

If ($iStatusCode <> 200) Then
    ConsoleWrite("Failed." & @CRLF)
    Exit
EndIf

; A successful response body contains JSON like this:
; Note: Azure's documentation is not very clear, but base64url is the encoding, not "base64".
; {
;   "kid": "https://kvchilkat.vault.azure.net/keys/importCert01/7140c8755ed14839b5d86a9f7e7f0497",
;   "value": "JzWd2YF21gjtW ... Em37hKOQ"
; }

; Let's validate the signature using the cert's public key.
; This example will load the corresponding certificate from a local file and will verify the signature against the original data.
; 
$oCert = ObjCreate("Chilkat.Cert")
$bSuccess = $oCert.LoadFromFile("qa_data/certs/chilkat_code_signing_2024.cer")
If ($bSuccess = False) Then
    ConsoleWrite($oCert.LastErrorText & @CRLF)
    Exit
EndIf

$oRsa = ObjCreate("Chilkat.Rsa")
; Tell the RSA object to use the cert's public key.
$bSuccess = $oRsa.SetX509Cert($oCert,False)
If ($bSuccess = False) Then
    ConsoleWrite($oRsa.LastErrorText & @CRLF)
    Exit
EndIf

; Verify the signature using the cert's public key against the original string.
$oRsa.EncodingMode = "base64url"
Local $bValid = $oRsa.VerifyStringENC($signedString,"sha-256",$oJsonResp.StringOf("value"))
ConsoleWrite("signature valid = " & $bValid & @CRLF)