pkg crypto/tls, type Config struct, GetCertificate func(*ClientHelloInfo) (*Certificate, error)
pkg crypto/tls, type ConnectionState struct, TLSUnique []uint8

# CL 153420045 crypto/x509: continue to recognise MaxPathLen of zero as "no value"., Adam Langley <******@****.***>
pkg crypto/x509, type Certificate struct, MaxPathLenZero bool

		},
		config.HelpKV{
			Key:         config.IdentityLDAPSubSys,
			Description: "enable LDAP SSO support",
		},
		config.HelpKV{
			Key:         config.IdentityTLSSubSys,
			Description: "enable X.509 TLS certificate SSO support",
		},
		config.HelpKV{
			Key:         config.IdentityPluginSubSys,
			Description: "enable Identity Plugin via external hook",
		},
		config.HelpKV{
			Key:         config.PolicyPluginSubSys,

- Fixes an issue where the vsphere cloud provider will not trust a certificate if:
  - The issuer of the certificate is unknown (x509.UnknownAuthorityError)
  - The requested name does not match the set of authorized names (x509.HostnameError)

///

要从用户的视角**了解 HTTPS 的基础知识**，请查看 <a href="https://howhttps.works/" class="external-link" target="_blank">https://howhttps.works/</a>。

现在，从**开发人员的视角**，在了解 HTTPS 时需要记住以下几点：

* 要使用 HTTPS，**服务器**需要拥有由**第三方**生成的**"证书(certificate)"**。
     * 这些证书实际上是从第三方**获取**的，而不是“生成”的。
* 证书有**生命周期**。
     * 它们会**过期**。
     * 然后它们需要**更新**，**再次从第三方获取**。
* 连接的加密发生在 **TCP 层**。
     * 这是 HTTP 协议**下面的一层**。
     * 因此，**证书和加密**处理是在 **HTTP之前**完成的。

                    <mxGeometry x="510" y="400" width="310" height="320" as="geometry"/>
                </mxCell>
                <mxCell id="50" value="&lt;font style=&quot;font-size: 24px&quot; face=&quot;Roboto&quot;&gt;HTTPS certificates&lt;br&gt;&lt;/font&gt;" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;strokeWidth=3;fontFamily=Roboto Mono, mono;FType=g;" parent="1" vertex="1">

- Kubeadm: during execution of the "check expiration" command, treat the etcd CA as external if there is a missing etcd CA key file (etcd/ca.key) and perform the proper validation on certificates signed by the etcd CA. Additionally, make sure that the CA for all...

                    <mxGeometry x="510" y="400" width="310" height="320" as="geometry"/>
                </mxCell>
                <mxCell id="50" value="&lt;font style=&quot;font-size: 24px&quot; face=&quot;Roboto&quot;&gt;HTTPS certificates&lt;br&gt;&lt;/font&gt;" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;strokeWidth=3;fontFamily=Roboto Mono, mono;FType=g;" parent="1" vertex="1">

- Kubeadm: during execution of the "check expiration" command, treat the etcd CA as external if there is a missing etcd CA key file (etcd/ca.key) and perform the proper validation on certificates signed by the etcd CA. Additionally, make sure that the CA for all...

- Fix an error when using external etcd but storing etcd certificates in the same folder with the same name used by kubeadm for local etcd certificates; for an older version of kubeadm, the workaround is to avoid file name used by kubeadm for local etcd. ([#80867](https://github.com/kubernetes/kubernetes/pull/80867), [@fabriziopandini](https://github.c...

    contents = f.read()
    print(contents)
```

Por baixo dos panos, o código `open("./somefile.txt")` cria um objeto que é chamado de "Gerenciador de Contexto".

Quando o bloco `with` finaliza, ele se certifica de fechar o arquivo, mesmo que tenha ocorrido alguma exceção.