import android.os.Build;
import androidx.test.ext.junit.runners.AndroidJUnit4;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.security.cert.Certificate;
import java.security.cert.CertificateException;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;

import okhttp3.OkHttpClient;
import okhttp3.Protocol;
import okhttp3.Request;
import okhttp3.Response;

track][tls_history] the dynamic TLS ecosystem and adjust OkHttp to improve connectivity and
security.

OkHttp uses your platform's built-in TLS implementation. On Java platforms OkHttp also supports
[Conscrypt][conscrypt], which integrates [BoringSSL](https://github.com/google/boringssl) with Java. OkHttp will use Conscrypt if it is
the first security provider:

```java

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.internal.tls

import java.security.GeneralSecurityException
import java.security.cert.Certificate
import java.security.cert.X509Certificate
import java.util.ArrayDeque
import java.util.Deque
import javax.net.ssl.SSLPeerUnverifiedException

/**

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.recipes;

import java.io.IOException;
import java.security.cert.X509Certificate;
import okhttp3.Headers;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
import okhttp3.tls.Certificates;
import okhttp3.tls.HandshakeCertificates;

 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package okhttp3.internal.tls

import java.security.cert.Certificate
import java.security.cert.X509Certificate
import javax.net.ssl.SSLPeerUnverifiedException
import javax.net.ssl.X509TrustManager
import okhttp3.internal.platform.Platform

/**

          Security.insertProviderAt(BouncyCastleProvider(), 1)
          Security.insertProviderAt(BouncyCastleJsseProvider(), 2)
        } else if (platformSystemProperty == CORRETTO_PROPERTY) {
          AmazonCorrettoCryptoProvider.install()

          AmazonCorrettoCryptoProvider.INSTANCE.assertHealthy()
        }

        Platform.resetForTests()

 * limitations under the License.
 */
@file:Suppress("INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")

package okhttp3.tls

import java.security.KeyStoreException
import java.security.SecureRandom
import java.security.cert.X509Certificate
import java.util.Collections
import javax.net.ssl.HostnameVerifier
import javax.net.ssl.KeyManager
import javax.net.ssl.SSLContext

Specific security vs. connectivity decisions are implemented by [ConnectionSpec](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-connection-spec/). OkHttp includes four built-in connection specs:

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.internal.platform

import java.security.KeyStore
import java.security.Provider
import java.security.cert.X509Certificate
import javax.net.ssl.SSLContext
import javax.net.ssl.SSLSession
import javax.net.ssl.SSLSocket
import javax.net.ssl.SSLSocketFactory
import javax.net.ssl.TrustManager

 * limitations under the License.
 */

@file:JvmName("Certificates")

package okhttp3.tls

import java.security.GeneralSecurityException
import java.security.cert.CertificateFactory
import java.security.cert.X509Certificate
import okio.Buffer
import okio.ByteString
import okio.ByteString.Companion.toByteString

/**