* future frames won't arrive on the stream ID.
 */
interface PushObserver {
  /**
   * Describes the request that the server intends to push a response for.
   *
   * @param streamId server-initiated stream ID: an even number.
   * @param requestHeaders minimally includes `:method`, `:scheme`, `:authority`,
   * and `:path`.
   */
  fun onRequest(
    streamId: Int,

var validSSEReplicationHeaders = map[string]string{
	"X-Minio-Internal-Server-Side-Encryption-Sealed-Key":     "X-Minio-Replication-Server-Side-Encryption-Sealed-Key",
	"X-Minio-Internal-Server-Side-Encryption-Seal-Algorithm": "X-Minio-Replication-Server-Side-Encryption-Seal-Algorithm",
	"X-Minio-Internal-Server-Side-Encryption-Iv":             "X-Minio-Replication-Server-Side-Encryption-Iv",

- `X-Amz-Server-Side-Encryption-Customer-Key`: Base64 encoded new key.
- `X-Amz-Copy-Source-Server-Side-Encryption-Customer-Key`: Base64 encoded current key.

Such a special COPY request is also known as S3 SSE-C key rotation.

### Server-Side Encryption with a KMS

SSE-S3 allows an S3 client to en/decrypt an object at the MinIO server using a KMS. The MinIO
server only assumes that the KMS provides two services:

/**
 * Performs either **preemptive** authentication before connecting to a proxy server, or
 * **reactive** authentication after receiving a challenge from either an origin web server or proxy
 * server.
 *
 * ## Preemptive Authentication
 *
 * To make HTTPS calls using an HTTP proxy server OkHttp must first negotiate a connection with
 * the proxy. This proxy connection is called a "TLS Tunnel" and is specified by

        // Note: Due to normalization, all multiple backslashes are reduced to single
        // so \\server\share becomes \server\share
        String path = "\\\\server\\share\\folder";
        String normalized = validator.validatePath(path);
        assertEquals("\\server\\share\\folder", normalized);
    }

    @Test
    public void testUncPathNotAllowed() throws Exception {

    # include /etc/nginx/conf.d/*.conf;

    upstream minio {
        server minio1:9000;
        server minio2:9000;
        server minio3:9000;
        server minio4:9000;
    }

    upstream console {
        ip_hash;
        server minio1:9001;
        server minio2:9001;
        server minio3:9001;
        server minio4:9001;
    }

    server {
        listen       9000;
        listen  [::]:9000;

### Server Binaries

filename | sha256 hash
-------- | -----------
[kubernetes-server-linux-amd64.tar.gz](https://dl.k8s.io/v1.5.8/kubernetes-server-linux-amd64.tar.gz) | `7e17b17e967722546541fdaeead4dc40037ddce4107aa2b2a561ea577aa62101`

    upstream minio {
        server minio1:9000 max_fails=1 fail_timeout=10s;
        server minio2:9000 max_fails=1 fail_timeout=10s;
        server minio3:9000 max_fails=1 fail_timeout=10s;
        server minio4:9000 max_fails=1 fail_timeout=10s;
    }

    upstream console {
        ip_hash;
        server minio1:9001;
        server minio2:9001;
        server minio3:9001;
        server minio4:9001;
    }

    HandshakeCertificates serverCertificates = new HandshakeCertificates.Builder()
        .heldCertificate(localhostCertificate)
        .build();
    MockWebServer server = new MockWebServer();
    server.useHttps(serverCertificates.sslSocketFactory(), false);
    server.enqueue(new MockResponse());

    HandshakeCertificates clientCertificates = new HandshakeCertificates.Builder()
        .addTrustedCertificate(localhostCertificate.certificate())

```

### TLS (FTP)

Unlike SFTP server, FTP server is insecure by default. To operate under TLS mode, you need to provide certificates via

```
--ftp="tls-private-key=path/to/private.key" --ftp="tls-public-cert=path/to/public.crt"
```

> NOTE: if MinIO distributed setup is already configured to run under TLS, FTP will automatically use the relevant