Add test of parseFidoSerNumExtension with real enterprise attestation cert

Author: emlun

webauthn-server-attestation/src/test/scala/com/yubico/webauthn/attestation/CertificateUtilSpec.scala

@@ -1,5 +1,7 @@
 package com.yubico.webauthn.attestation
 
+import com.yubico.internal.util.BinaryUtil
+import com.yubico.internal.util.CertificateParser
 import com.yubico.webauthn.TestAuthenticator
 import com.yubico.webauthn.data.ByteArray
 import org.bouncycastle.asn1.DEROctetString
@@ -10,6 +12,7 @@ import org.scalatest.matchers.should.Matchers
 import org.scalatestplus.junit.JUnitRunner
 
 import java.security.cert.X509Certificate
+import scala.jdk.OptionConverters.RichOptional
 
 @RunWith(classOf[JUnitRunner])
 class CertificateUtilSpec extends AnyFunSpec with Matchers {
@@ -39,6 +42,36 @@ class CertificateUtilSpec extends AnyFunSpec with Matchers {
       result should equal(ByteArray.fromHex("00010203"))
     }
 
-  }
+    it("correctly parses the serial number from a real YubiKey enterprise attestation certificate.") {
+      val cert = CertificateParser.parsePem("""-----BEGIN CERTIFICATE-----
+        |MIIC8zCCAdugAwIBAgIJAKr/KiUzkKrgMA0GCSqGSIb3DQEBCwUAMC8xLTArBgNV
+        |BAMMJFl1YmljbyBGSURPIFJvb3QgQ0EgU2VyaWFsIDQ1MDIwMzU1NjAgFw0yNDA1
+        |MDEwMDAwMDBaGA8yMDYwMDQzMDAwMDAwMFowcDELMAkGA1UEBhMCU0UxEjAQBgNV
+        |BAoMCVl1YmljbyBBQjEiMCAGA1UECwwZQXV0aGVudGljYXRvciBBdHRlc3RhdGlv
+        |bjEpMCcGA1UEAwwgWXViaWNvIEZpZG8gRUUgKFNlcmlhbD0yODI5OTAwMykwWTAT
+        |BgcqhkjOPQIBBggqhkjOPQMBBwNCAATImNkI1cwqkW5B3qNrY3pc8zBLhvGyfyfS
+        |WCLrODSe8xaRPcZoXYGGwZ0Ua/Hp5nxyD+w1hjS9O9gx8mSDvp+zo4GZMIGWMBMG
+        |CisGAQQBgsQKDQEEBQQDBQcBMBUGCysGAQQBguUcAQECBAYEBAGvzvswIgYJKwYB
+        |BAGCxAoCBBUxLjMuNi4xLjQuMS40MTQ4Mi4xLjcwEwYLKwYBBAGC5RwCAQEEBAMC
+        |AiQwIQYLKwYBBAGC5RwBAQQEEgQQuQ59wTFuT+6iWlamZqZw/jAMBgNVHRMBAf8E
+        |AjAAMA0GCSqGSIb3DQEBCwUAA4IBAQAFEMXw1HUDC/TfMFxp2ZrmgQLa5fmzs2Jh
+        |C22TUAuY26CYT5dmMUsS5aJd96MtC5gKS57h1auGr2Y4FMxQS9FJHzXAzAtYJfKh
+        |j1uS2BSTXf9GULdFKcWvvv50kJ2VmXLge3UgHDBJ8LwrDlZFyISeMZ8jSbmrNu2c
+        |8uNBBSfqdor+5H91L1brC9yYneHdxYk6YiEvDBxWjiMa9DQuySh/4a21nasgt0cB
+        |prEbfFOLRDm7GDsRTPyefZjZ84yi4Ao+15x+7DM0UwudEVtjOWB2BJtJyxIkXXNF
+        |iWFZaxezq0Xt2Kl2sYnMR97ynw/U4TzZDjgb56pN81oKz8Od9B/u
+        |-----END CERTIFICATE-----""".stripMargin)
+
+      val result =
+        CertificateUtil
+          .parseFidoSerNumExtension(cert)
+          .toScala
+          .map(new ByteArray(_))
 
+      result should equal(Some(ByteArray.fromHex("01AFCEFB")))
+
+      // For YubiKeys, the sernum octet string represents a big-endian integer
+      BinaryUtil.getUint32(result.get.getBytes) should be(28299003)
+    }
+  }
 }