*/
abstract class EventListener {
  /**
   * Invoked as soon as a call is enqueued or executed by a client. In case of thread or stream
   * limits, this call may be executed well before processing the request is able to begin.
   *
   * This will be invoked only once for a single [Call]. Retries of different routes or redirects
   * will be handled within the boundaries of a single [callStart] and [callEnd]/[callFailed] pair.
   */

      |
      """.trimMargin()
    val pkcs8Pem =
      """
      |-----BEGIN PRIVATE KEY-----
      |MEECAQAwEwYHKoZIzj0CAQYIKoZIzj0DAQcEJzAlAgEBBCA7ODT0xhGSNn4ESj6J
      |lu/GJQZoU9lDrCPeUcQ28tzOWw==
      |-----END PRIVATE KEY-----
      |
      """.trimMargin()
    val bcPkcs8Pem =
      """
      |-----BEGIN PRIVATE KEY-----
      |ME0CAQAwEwYHKoZIzj0CAQYIKoZIzj0DAQcEMzAxAgEBBCA7ODT0xhGSNn4ESj6J

  val decoded = Punycode.decode(bufferA.readUtf8()) ?: return null

  // 4.1 Validate.

  // Must be NFC.
  if (decoded != normalizeNfc(decoded)) return null

  // TODO: Must not begin with a combining mark.
  // TODO: Each character must be 'valid' or 'deviation'. Not mapped.
  // TODO: CheckJoiners from IDNA 2008
  // TODO: CheckBidi from IDNA 2008, RFC 5893, Section 2.

    string containing both a certificate and PKCS #8-encoded private key.

    ```kotlin
    val heldCertificate = HeldCertificate.decode("""
        |-----BEGIN CERTIFICATE-----
        |MIIBYTCCAQegAwIBAgIBKjAKBggqhkjOPQQDAjApMRQwEgYDVQQLEwtlbmdpbmVl
        |cmluZzERMA8GA1UEAxMIY2FzaC5hcHAwHhcNNzAwMTAxMDAwMDA1WhcNNzAwMTAx

      |jaA9VEhgdaVhxBsT2qzUNDsXlOzGsliznDfoqETb
      |
      """.trimMargin()
    val certificateByteString = certificateBase64.decodeBase64()!!
    val certificatePem =
      """
      |-----BEGIN CERTIFICATE-----
      |$certificateBase64
      |-----END CERTIFICATE-----
      |
      """.trimMargin()

    val javaCertificate = certificatePem.decodeCertificatePem()
    val okHttpCertificate =

  companion object {
    private val PEM_REGEX = Regex("""-----BEGIN ([!-,.-~ ]*)-----([^-]*)-----END \1-----""")

    /**
     * Decodes a multiline string that contains both a [certificate][certificatePem] and a
     * [private key][privateKeyPkcs8Pem], both [PEM-encoded][rfc_7468]. A typical input string looks
     * like this:
     *
     * ```
     * -----BEGIN CERTIFICATE-----

    val session = FakeSSLSession()
    assertThat(verifier.verify("localhost", session)).isFalse()
  }

  @Test fun verifyCn() {
    // CN=foo.com
    val session =
      session(
        """
        -----BEGIN CERTIFICATE-----
        MIIERjCCAy6gAwIBAgIJAIz+EYMBU6aQMA0GCSqGSIb3DQEBBQUAMIGiMQswCQYD
        VQQGEwJDQTELMAkGA1UECBMCQkMxEjAQBgNVBAcTCVZhbmNvdXZlcjEWMBQGA1UE