没有 TLS 的 Ingress gateway

阅读大约需要 3 分钟

使用 HTTPS 保护网关任务描述了如何配置 HTTPS 入口访问 HTTP 服务。此示例介绍如何配置对 HTTPS 服务的入口访问，即配置 Ingress Gateway 以执行 SNI 直通，而不是终止 TLS 请求的传入。

用于此任务的示例 HTTPS 服务是一个简单的 NGINX 服务器。在以下步骤中，首先在 Kubernetes 集群中部署 NGINX 服务。然后配置网关以通过主机 nginx.example.com 提供对此服务的入口访问。

生成客户端和服务器证书和密钥

以与使用 HTTPS 保护网关任务相同的方式生成证书和密钥。

克隆 https://github.com/nicholasjackson/mtls-go-example 存储库：
```
$ git clone https://github.com/nicholasjackson/mtls-go-example
```
将目录更改为克隆的存储库：
```
$ pushd mtls-go-example
```
为 nginx.example.com 生成证书。使用以下命令的任何密码：
```
$ ./generate.sh nginx.example.com password
```
遇见所有的问题请输入 y 来回答。

将证书移动到 nginx.example.com 目录：

$ mkdir ../nginx.example.com && mv 1_root 2_intermediate 3_application 4_client ../nginx.example.com

返回根目录：
```
$ popd
```

部署 NGINX 服务器

创建一个 Kubernetes Secret来保存服务器的证书。

$ kubectl create secret tls nginx-server-certs --key nginx.example.com/3_application/private/nginx.example.com.key.pem --cert nginx.example.com/3_application/certs/nginx.example.com.cert.pem

为 NGINX 服务器创建配置文件：

$ cat <<EOF > ./nginx.conf
events {
}

http {
  log_format main '$remote_addr - $remote_user [$time_local]  $status '
  '"$request" $body_bytes_sent "$http_referer" '
  '"$http_user_agent" "$http_x_forwarded_for"';
  access_log /var/log/nginx/access.log main;
  error_log  /var/log/nginx/error.log;

  server {
    listen 443 ssl;

    root /usr/share/nginx/html;
    index index.html;

    server_name nginx.example.com;
    ssl_certificate /etc/nginx-server-certs/tls.crt;
    ssl_certificate_key /etc/nginx-server-certs/tls.key;
  }
}
EOF

创建 Kubernetes ConfigMap 保持 NGINX 服务器的配置：

$ kubectl create configmap nginx-configmap --from-file=nginx.conf=./nginx.conf

部署 NGINX 服务器：

$ kubectl apply -f - <<EOF
apiVersion: v1
kind: Service
metadata:
  name: my-nginx
  labels:
    run: my-nginx
spec:
  ports:
  - port: 443
    protocol: TCP
  selector:
    run: my-nginx
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-nginx
spec:
  selector:
    matchLabels:
      run: my-nginx
  replicas: 1
  template:
    metadata:
      labels:
        run: my-nginx
    spec:
      containers:
      - name: my-nginx
        image: nginx
        ports:
        - containerPort: 443
        volumeMounts:
        - name: nginx-config
          mountPath: /etc/nginx
          readOnly: true
        - name: nginx-server-certs
          mountPath: /etc/nginx-server-certs
          readOnly: true
      volumes:
      - name: nginx-config
        configMap:
          name: nginx-configmap
      - name: nginx-server-certs
        secret:
          secretName: nginx-server-certs
EOF

要测试 NGINX 服务器是否已成功部署，请从其 sidecar 代理向服务器发送请求，而不检查服务器的证书（使用 curl 的 -k 选项）。确保正确打印服务器的证书，即 common name 等于 nginx.example.com。

$ kubectl exec -it $(kubectl get pod  -l run=my-nginx -o jsonpath={.items..metadata.name}) -c istio-proxy -- curl -v -k --resolve nginx.example.com:443:127.0.0.1 https://nginx.example.com
...
SSL connection using TLS1.2 / ECDHE_RSA_AES_128_GCM_SHA256
  server certificate verification SKIPPED
  server certificate status verification SKIPPED
  common name: nginx.example.com (matched)
  server certificate expiration date OK
  server certificate activation date OK
  certificate public key: RSA
  certificate version: #3
  subject: C=US,ST=Denial,L=Springfield,O=Dis,CN=nginx.example.com
  start date: Wed, 15 Aug 2018 07:29:07 GMT
  expire date: Sun, 25 Aug 2019 07:29:07 GMT
  issuer: C=US,ST=Denial,O=Dis,CN=nginx.example.com

> GET / HTTP/1.1
> User-Agent: curl/7.35.0
> Host: nginx.example.com
...
< HTTP/1.1 200 OK

< Server: nginx/1.15.2
...
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
...

配置 Ingress Gateway

为端口 443 定义一个带有 server 部分的 Gateway 。注意 PASSTHROUGH tls mode 指示网关按原样传递入口流量，而不终止 TLS。

$ kubectl apply -f - <<EOF
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: mygateway
spec:
  selector:
    istio: ingressgateway # 使用 istio 默认的 ingress gateway
  servers:
  - port:
      number: 443
      name: https
      protocol: HTTPS
    tls:
      mode: PASSTHROUGH
    hosts:
    - nginx.example.com
EOF

配置通过 Gateway 进入的流量路由：

$ kubectl apply -f - <<EOF
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: nginx
spec:
  hosts:
  - nginx.example.com
  gateways:
  - mygateway
  tls:
  - match:
    - port: 443
      sni_hosts:
      - nginx.example.com
    route:
    - destination:
        host: my-nginx
        port:
          number: 443
EOF

按照确定入口IP和端口中的说明定义 SECURE_INGRESS_PORT 和 INGRESS_HOST 环境变量。

从群集外部访问 NGINX 服务。请注意，服务器返回正确的证书并成功验证（打印 SSL certificate verify ok ）。

$ curl -v --resolve nginx.example.com:$SECURE_INGRESS_PORT:$INGRESS_HOST --cacert nginx.example.com/2_intermediate/certs/ca-chain.cert.pem https://nginx.example.com:$SECURE_INGRESS_PORT
Server certificate:
  subject: C=US; ST=Denial; L=Springfield; O=Dis; CN=nginx.example.com
  start date: Aug 15 07:29:07 2018 GMT
  expire date: Aug 25 07:29:07 2019 GMT
  common name: nginx.example.com (matched)
  issuer: C=US; ST=Denial; O=Dis; CN=nginx.example.com
  SSL certificate verify ok.

  < HTTP/1.1 200 OK
  < Server: nginx/1.15.2
  ...
  <html>
  <head>
  <title>Welcome to nginx!</title>

清理

删除创建的 Kubernetes 资源：

$ kubectl delete secret nginx-server-certs
$ kubectl delete configmap nginx-configmap
$ kubectl delete service my-nginx
$ kubectl delete deployment my-nginx
$ kubectl delete gateway mygateway
$ kubectl delete virtualservice nginx

删除包含证书的目录和用于生成证书的存储库：
```
$ rm -rf nginx.example.com mtls-go-example
```
删除此示例中使用的生成的配置文件：
```
$ rm -f ./nginx.conf
```