if err != nil {
		return nil, nil, fmt.Errorf("Failed to create certificate: %w", err)
	}

	certOut := bytes.NewBuffer([]byte{})
	pem.Encode(certOut, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes})

	keyOut := bytes.NewBuffer([]byte{})
	pem.Encode(keyOut, pemBlockForKey(priv))

	return certOut.Bytes(), keyOut.Bytes(), nil
}

* 3.3 [Use OpenSSL (with IP address) to Generate a Certificate](#using-open-ssl-with-ip)
* 3.4 [Use GnuTLS (for Windows) to Generate a Certificate](#using-gnu-tls)

**Note:**

* MinIO only supports keys and certificates in PEM format on Linux and Windows.
* MinIO doesn't currently support PFX certificates.

### 3.1 Use `certgen` to Generate a Certificate

`client-certificate: /var/lib/kubelet/pki/kubelet-client-current.pem` and `client-key: /var/lib/kubelet/pki/kubelet-client-current.pem`, replacing the embedded client certificate and key. ([#84118](https://github.com/kubernetes/kubernetes/pull/84118), [@neolit123](https://github.com/neolit123))

package cmd

import (
	"bytes"
	"context"
	crand "crypto/rand"
	"crypto/rsa"
	"crypto/subtle"
	"crypto/x509"
	"encoding/base64"
	"encoding/json"
	"encoding/pem"
	"errors"
	"fmt"
	"hash/crc32"
	"io"
	"math"
	"net/http"
	"net/url"
	"os"
	"path"
	"path/filepath"
	"regexp"
	"runtime"
	"sort"
	"strconv"
	"strings"
	"sync/atomic"
	"time"

`kubelet-client.crt`.  Subsequent certificates created by cert rotation were created in a combined PEM file that was atomically rotated as `kubelet-client-DATE.pem` in that directory, which meant clients relying on the `node.kubeconfig` generated by bootstrapping would never use a rotated cert.  The initial bootstrap certificate is now generated into the cert directory as a PEM file and symlinked to `kubelet-client-current.pem` so that the generated kubeconfig remains valid after rotation. ([#62152](https://gi...

    <alias type="application/x-x509-user-cert"/>
    <glob pattern="*.crt"/>
  </mime-type>
  <mime-type type="application/x-x509-cert;format=pem">
    <sub-class-of type="application/x-x509-cert"/>
    <glob pattern="*.pem"/>
    <magic priority="50">
      <match value="-----BEGIN CERTIFICATE-----" type="string" offset="0"/>
    </magic>
  </mime-type>

    builder then use it to sign another certificate or perform a TLS handshake. The
    `certificatePem()` method encodes the certificate in the familiar PEM format
    (`--- BEGIN CERTIFICATE ---`); the `privateKeyPkcs8Pem()` does likewise for the private key.

    `HandshakeCertificates` holds the TLS certificates required for a TLS handshake. On the server

- Kubeadm: tolerate whitespace when validating certificate authority PEM data in kubeconfig files ([#86705](https://github.com/kubernetes/kubernetes/pull/86705), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

- Reduced memory utilization of admission webhook metrics by removing resource related labels. ([#69895](https://github.com/kubernetes/kubernetes/pull/69895), [@jpbetz](https://github.com/jpbetz))
- Kubelet can now parse PEM file containing both TLS certificate and key in arbitrary order. Previously key was always required to be first. ([#69536](https://github.com/kubernetes/kubernetes/pull/69536), [@awly](https://github.com/awly))

- Updated the control plane's trust anchor publisher to create and manage a new ClusterTrustBundle object, associated with the `kubernetes.io/kube-apiserver-serving` X.509 certificate signer. This ClusterTrustBundle contains a PEM bundle in its payload that you can use to verify kube-apiserver serving certificates. ([#127326](https://github.com/kubernetes/kubernetes/pull/127326), [@stlaz](https://github.com/stlaz)) [SIG API Machinery, Apps, Auth, Cluster Lifecycle and Testing]...