距离 Istio 1.5 版本发布还有 天。

Egress 网关的 TLS 发起过程

为 Egress 流量发起 TLS 连接 示例中演示了如何配置 Istio 以对外部服务流量实施 TLS origination配置 Egress Gateway 示例中演示了如何配置 Istio 来通过专门的 egress 网关服务引导 egress 流量。 本示例兼容以上两者,描述如何配置 egress 网关,为外部服务流量发起 TLS 连接。

开始之前

  • 遵照安装指南中的指令,安装 Istio。

  • 启动 sleep 样本应用,作为外部请求的测试源。

    若已开启 自动 sidecar 注入,执行

    Zip
    $ kubectl apply -f @samples/sleep/sleep.yaml@
    

    否则,必须在部署 sleep 应用之前手动注入 sidecar:

    Zip
    $ kubectl apply -f <(istioctl kube-inject -f @samples/sleep/sleep.yaml@)
    

    注意每一个可以执行 execcurl 操作的 pod,都需要注入。

  • 创建一个 shell 变量,来保存向外部服务发送请求的源 pod 的名称。 若使用 sleep 样例,运行:

    $ export SOURCE_POD=$(kubectl get pod -l app=sleep -o jsonpath={.items..metadata.name})
    
  • 部署 Istio egress 网关

  • 开启 Envoy 的访问日志

通过 egress 网关发起 TLS 连接

本节描述如何使用 egress 网关发起与示例为 Egress 流量发起 TLS 连接 中一样的 TLS。 注意,这种情况下,TLS 的发起过程由 egress 网关完成,而不是像之前示例演示的那样由 sidecar 完成。

  1. edition.cnn.com 定义一个 ServiceEntry

    $ kubectl apply -f - <<EOF
    apiVersion: networking.istio.io/v1alpha3
    kind: ServiceEntry
    metadata:
      name: cnn
    spec:
      hosts:
      - edition.cnn.com
      ports:
      - number: 80
        name: http
        protocol: HTTP
      - number: 443
        name: https
        protocol: HTTPS
      resolution: DNS
    EOF
    
  2. 发送一个请求至 http://edition.cnn.com/politics,验证 ServiceEntry 已被正确应用。

    $ kubectl exec -it $SOURCE_POD -c sleep -- curl -sL -o /dev/null -D - http://edition.cnn.com/politics
    HTTP/1.1 301 Moved Permanently
    ...
    location: https://edition.cnn.com/politics
    ...
    
    command terminated with exit code 35
    

    如果在输出中看到 _301 Moved Permanently_,说明 ServiceEntry 配置正确。

  3. edition.cnn.com 创建一个 egress Gateway, 端口 443,以及一个 sidecar 请求的目标规则,sidecar 请求被直接导向 egress 网关。

    根据需要开启源 pod 与 egress 网关之间的双向 TLS 认证,选择相应的命令。

    $ kubectl apply -f - <<EOF
    apiVersion: networking.istio.io/v1alpha3
    kind: Gateway
    metadata:
      name: istio-egressgateway
    spec:
      selector:
    istio: egressgateway
      servers:
      - port:
      number: 80
      name: https
      protocol: HTTPS
    hosts:
    - edition.cnn.com
    tls:
      mode: MUTUAL
      serverCertificate: /etc/certs/cert-chain.pem
      privateKey: /etc/certs/key.pem
      caCertificates: /etc/certs/root-cert.pem
    ---
    apiVersion: networking.istio.io/v1alpha3
    kind: DestinationRule
    metadata:
      name: egressgateway-for-cnn
    spec:
      host: istio-egressgateway.istio-system.svc.cluster.local
      subsets:
      - name: cnn
    trafficPolicy:
      loadBalancer:
        simple: ROUND_ROBIN
      portLevelSettings:
      - port:
          number: 80
        tls:
          mode: ISTIO_MUTUAL
          sni: edition.cnn.com
    EOF
    
  4. 定义一个 VirtualService 来引导流量流经 egress 网关,以及一个 DestinationRule 为访问 edition.cnn.com 的请求发起 TLS 连接:

    $ kubectl apply -f - <<EOF
    apiVersion: networking.istio.io/v1alpha3
    kind: VirtualService
    metadata:
      name: direct-cnn-through-egress-gateway
    spec:
      hosts:
      - edition.cnn.com
      gateways:
      - istio-egressgateway
      - mesh
      http:
      - match:
        - gateways:
          - mesh
          port: 80
        route:
        - destination:
            host: istio-egressgateway.istio-system.svc.cluster.local
            subset: cnn
            port:
              number: 80
          weight: 100
      - match:
        - gateways:
          - istio-egressgateway
          port: 80
        route:
        - destination:
            host: edition.cnn.com
            port:
              number: 443
          weight: 100
    ---
    apiVersion: networking.istio.io/v1alpha3
    kind: DestinationRule
    metadata:
      name: originate-tls-for-edition-cnn-com
    spec:
      host: edition.cnn.com
      trafficPolicy:
        loadBalancer:
          simple: ROUND_ROBIN
        portLevelSettings:
        - port:
            number: 443
          tls:
            mode: SIMPLE # initiates HTTPS for connections to edition.cnn.com
    EOF
    
  5. 发送一个 HTTP 请求至 http://edition.cnn.com/politics

    $ kubectl exec -it $SOURCE_POD -c sleep -- curl -sL -o /dev/null -D - http://edition.cnn.com/politics
    HTTP/1.1 200 OK
    ...
    content-length: 150793
    ...
    

    输出将与在示例 为 Egress 流量发起 TLS 连接 中显示的一样,发起 TLS 连接后,不再显示 301 Moved Permanently 消息。

  6. 检查 istio-egressgateway pod 的日志,将看到一行与请求相关的记录。 若 Istio 部署在 istio-system 命名空间中,打印日志的命令为:

    $ kubectl logs -l istio=egressgateway -c istio-proxy -n istio-system | tail
    

    将看到类似如下一行:

    "[2018-06-14T13:49:36.340Z] "GET /politics HTTP/1.1" 200 - 0 148528 5096 90 "172.30.146.87" "curl/7.35.0" "c6bfdfc3-07ec-9c30-8957-6904230fd037" "edition.cnn.com" "151.101.65.67:443"
    

清除 TLS 启动实例

删除创建的 Istio 配置项:

$ kubectl delete gateway istio-egressgateway
$ kubectl delete serviceentry cnn
$ kubectl delete virtualservice direct-cnn-through-egress-gateway
$ kubectl delete destinationrule originate-tls-for-edition-cnn-com
$ kubectl delete destinationrule egressgateway-for-cnn

通过 egress 网关发起双向 TLS 连接

与前一章节类似,本章节描述如何配置一个 egress 网关,为外部服务发起 TLS 连接,只是这次服务要求双向 TLS。

本示例要求更高的参与性,首先需要:

  1. 生成客户端和服务器证书
  2. 部署一个支持双向 TLS 的外部服务
  3. 使用所需的证书重新部署 egress 网关

然后才可以配置出口流量流经 egress 网关,egress 网关将发起 TLS 连接。

生成客户端和服务器的证书与密钥

  1. 克隆示例代码库 https://github.com/nicholasjackson/mtls-go-example

    $ git clone https://github.com/nicholasjackson/mtls-go-example
    
  2. 进入克隆的代码库目录:

    $ cd mtls-go-example
    
  3. nginx.example.com 生成证书。 使用任意 password 执行如下命令:

    $ ./generate.sh nginx.example.com <password>
    

    所有出现的提示,均选择 y

  4. 将证书迁移至 nginx.example.com 目录:

    $ mkdir ../nginx.example.com && mv 1_root 2_intermediate 3_application 4_client ../nginx.example.com
    
  5. 返回至上一级目录:

    $ cd ..
    

部署一个双向 TLS 服务器

为了模拟一个真实的支持双向 TLS 协议的外部服务, 在 Kubernetes 集群中部署一个 NGINX 服务器,该服务器运行在 Istio 服务网格之外,譬如:运行在一个没有开启 Istio sidecar proxy 注入的命名空间中。

  1. 创建一个命名空间,表示 Istio 网格之外的服务, mesh-external。注意在这个命名空间中,sidecar 自动注入是没有开启 的,不会在 pods 中自动注入 sidecar proxy。

    $ kubectl create namespace mesh-external
    
  2. 创建 Kubernetes Secrets ,保存服务器和 CA 的证书。

    $ kubectl create -n mesh-external 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
    $ kubectl create -n mesh-external secret generic nginx-ca-certs --from-file=nginx.example.com/2_intermediate/certs/ca-chain.cert.pem
    
  3. 生成 NGINX 服务器的配置文件:

    $ 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;
        ssl_client_certificate /etc/nginx-ca-certs/ca-chain.cert.pem;
        ssl_verify_client on;
      }
    }
    EOF
    
  4. 生成 Kubernetes ConfigMap 保存 NGINX 服务器的配置文件:

    $ kubectl create configmap nginx-configmap -n mesh-external --from-file=nginx.conf=./nginx.conf
    
  5. 部署 NGINX 服务器:

    $ kubectl apply -f - <<EOF
    apiVersion: v1
    kind: Service
    metadata:
      name: my-nginx
      namespace: mesh-external
      labels:
        run: my-nginx
    spec:
      ports:
      - port: 443
        protocol: TCP
      selector:
        run: my-nginx
    ---
    apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: my-nginx
      namespace: mesh-external
    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
            - name: nginx-ca-certs
              mountPath: /etc/nginx-ca-certs
              readOnly: true
          volumes:
          - name: nginx-config
            configMap:
              name: nginx-configmap
          - name: nginx-server-certs
            secret:
              secretName: nginx-server-certs
          - name: nginx-ca-certs
            secret:
              secretName: nginx-ca-certs
    EOF
    
  6. nginx.example.com 定义一个 ServiceEntry 和一个 VirtualService,指示 Istio 引导目标为 nginx.example.com 的流量流向 NGINX 服务器:

    $ kubectl apply -f - <<EOF
    apiVersion: networking.istio.io/v1alpha3
    kind: ServiceEntry
    metadata:
      name: nginx
    spec:
      hosts:
      - nginx.example.com
      ports:
      - number: 80
        name: http
        protocol: HTTP
      - number: 443
        name: https
        protocol: HTTPS
      resolution: DNS
      endpoints:
      - address: my-nginx.mesh-external.svc.cluster.local
        ports:
          https: 443
    ---
    apiVersion: networking.istio.io/v1alpha3
    kind: VirtualService
    metadata:
      name: nginx
    spec:
      hosts:
      - nginx.example.com
      tls:
      - match:
        - port: 443
          sni_hosts:
          - nginx.example.com
        route:
        - destination:
            host: nginx.example.com
            port:
              number: 443
          weight: 100
    EOF
    

部署一个容器测试 nginx 部署

  1. 生成 Kubernetes Secrets ,保存客户端和 CA 的证书:

    $ kubectl create secret tls nginx-client-certs --key nginx.example.com/4_client/private/nginx.example.com.key.pem --cert nginx.example.com/4_client/certs/nginx.example.com.cert.pem
    $ kubectl create secret generic nginx-ca-certs --from-file=nginx.example.com/2_intermediate/certs/ca-chain.cert.pem
    
  2. 基于挂载的客户端和 CA 证书,部署 sleep 样本应用,测试发送请求至 NGINX 服务器:

    $ kubectl apply -f - <<EOF
    # Copyright 2017 Istio Authors
    #
    #   Licensed under the Apache License, Version 2.0 (the "License");
    #   you may not use this file except in compliance with the License.
    #   You may obtain a copy of the License at
    #
    #       http://www.apache.org/licenses/LICENSE-2.0
    #
    #   Unless required by applicable law or agreed to in writing, software
    #   distributed under the License is distributed on an "AS IS" BASIS,
    #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    #   See the License for the specific language governing permissions and
    #   limitations under the License.
    
    ##################################################################################################
    # Sleep service
    ##################################################################################################
    apiVersion: v1
    kind: Service
    metadata:
      name: sleep
      labels:
        app: sleep
    spec:
      ports:
      - port: 80
        name: http
      selector:
        app: sleep
    ---
    apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: sleep
    spec:
      replicas: 1
      template:
        metadata:
          labels:
            app: sleep
        spec:
          containers:
          - name: sleep
            image: tutum/curl
            command: ["/bin/sleep","infinity"]
            imagePullPolicy: IfNotPresent
            volumeMounts:
            - name: nginx-client-certs
              mountPath: /etc/nginx-client-certs
              readOnly: true
            - name: nginx-ca-certs
              mountPath: /etc/nginx-ca-certs
              readOnly: true
          volumes:
          - name: nginx-client-certs
            secret:
              secretName: nginx-client-certs
          - name: nginx-ca-certs
            secret:
              secretName: nginx-ca-certs
    EOF
    
  3. 定义一个环境变量保存 sleep pod 的名称:

    $ export SOURCE_POD=$(kubectl get pod -l app=sleep -o jsonpath={.items..metadata.name})
    
  4. 使用部署的 sleep pod 向 NGINX 服务器发送请求。 由于 nginx.example.com 不是真实存在的,DNS 无法解析,后面的 curl 命令使用 --resolve 选项手动解析主机名。 –resolve 选项传递的 IP 值(下方所示,1.1.1.1)没有意义。除 127.0.0.1 之外的任意值都可以使用。 一般情况下,目标主机名对应着一个 DNS 项,无需使用 curl--resolve 选项。

    $ kubectl exec -it $SOURCE_POD -c sleep -- curl -v --resolve nginx.example.com:443:1.1.1.1 --cacert /etc/nginx-ca-certs/ca-chain.cert.pem --cert /etc/nginx-client-certs/tls.crt --key /etc/nginx-client-certs/tls.key https://nginx.example.com
    ...
    Server certificate:
      subject: C=US; ST=Denial; L=Springfield; O=Dis; CN=nginx.example.com
      start date: 2018-08-16 04:31:20 GMT
      expire date: 2019-08-26 04:31:20 GMT
      common name: nginx.example.com (matched)
      issuer: C=US; ST=Denial; O=Dis; CN=nginx.example.com
      SSL certificate verify ok.
    > 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>
    ...
    
  5. 验证服务器要求客户端的证书:

    $ kubectl exec -it $(kubectl get pod -l app=sleep -o jsonpath={.items..metadata.name}) -c sleep -- curl -k --resolve nginx.example.com:443:1.1.1.1 https://nginx.example.com
    <html>
    <head><title>400 No required SSL certificate was sent</title></head>
    <body bgcolor="white">
    <center><h1>400 Bad Request</h1></center>
    <center>No required SSL certificate was sent</center>
    <hr><center>nginx/1.15.2</center>
    </body>
    </html>
    

使用客户端证书重新部署 egress 网关

  1. 生成 Kubernetes Secrets 保存客户端和 CA 的证书。

    $ kubectl create -n istio-system secret tls nginx-client-certs --key nginx.example.com/4_client/private/nginx.example.com.key.pem --cert nginx.example.com/4_client/certs/nginx.example.com.cert.pem
    $ kubectl create -n istio-system secret generic nginx-ca-certs --from-file=nginx.example.com/2_intermediate/certs/ca-chain.cert.pem
    
  2. 部署 istio-egressgateway 挂载新生成的 secrets 的 volume。使用的参数选项与生成 istio.yaml 中的一致:

    $ istioctl manifest generate --set values.gateways.istio-ingressgateway.enabled=false \
    --set values.gateways.istio-egressgateway.enabled=true \
    --set 'values.gateways.istio-egressgateway.secretVolumes[0].name'=egressgateway-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[0].secretName'=istio-egressgateway-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[0].mountPath'=/etc/istio/egressgateway-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[1].name'=egressgateway-ca-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[1].secretName'=istio-egressgateway-ca-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[1].mountPath'=/etc/istio/egressgateway-ca-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[2].name'=nginx-client-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[2].secretName'=nginx-client-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[2].mountPath'=/etc/nginx-client-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[3].name'=nginx-ca-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[3].secretName'=nginx-ca-certs \
    --set 'values.gateways.istio-egressgateway.secretVolumes[3].mountPath'=/etc/nginx-ca-certs > \
    ./istio-egressgateway.yaml
    
  3. 重新部署 istio-egressgateway

    $ kubectl apply -f ./istio-egressgateway.yaml
    deployment "istio-egressgateway" configured
    
  4. 验证密钥和证书被成功装载入 istio-egressgateway pod:

    $ kubectl exec -it -n istio-system $(kubectl -n istio-system get pods -l istio=egressgateway -o jsonpath='{.items[0].metadata.name}') -- ls -al /etc/nginx-client-certs /etc/nginx-ca-certs
    

    tls.crttls.key/etc/istio/nginx-client-certs 中, 而 ca-chain.cert.pem/etc/istio/nginx-ca-certs 中。

为 egress 流量配置双向 TLS

  1. nginx.example.com 创建一个 egress Gateway 端口为 443,以及目标规则和虚拟服务来引导流量流经 egress 网关并从 egress 网关流向外部服务。

    $ kubectl apply -f - <<EOF
    apiVersion: networking.istio.io/v1alpha3
    kind: Gateway
    metadata:
      name: istio-egressgateway
    spec:
      selector:
        istio: egressgateway
      servers:
      - port:
          number: 443
          name: https
          protocol: HTTPS
        hosts:
        - nginx.example.com
        tls:
          mode: MUTUAL
          serverCertificate: /etc/certs/cert-chain.pem
          privateKey: /etc/certs/key.pem
          caCertificates: /etc/certs/root-cert.pem
    ---
    apiVersion: networking.istio.io/v1alpha3
    kind: DestinationRule
    metadata:
      name: egressgateway-for-nginx
    spec:
      host: istio-egressgateway.istio-system.svc.cluster.local
      subsets:
      - name: nginx
        trafficPolicy:
          loadBalancer:
            simple: ROUND_ROBIN
          portLevelSettings:
          - port:
              number: 443
            tls:
              mode: ISTIO_MUTUAL
              sni: nginx.example.com
    EOF
    
  2. 定义一个 VirtualService 引导流量流经 egress 网关,一个 DestinationRule 发起双向 TLS 连接:

    $ kubectl apply -f - <<EOF
    apiVersion: networking.istio.io/v1alpha3
    kind: VirtualService
    metadata:
      name: direct-nginx-through-egress-gateway
    spec:
      hosts:
      - nginx.example.com
      gateways:
      - istio-egressgateway
      - mesh
      http:
      - match:
        - gateways:
          - mesh
          port: 80
        route:
        - destination:
            host: istio-egressgateway.istio-system.svc.cluster.local
            subset: nginx
            port:
              number: 443
          weight: 100
      - match:
        - gateways:
          - istio-egressgateway
          port: 443
        route:
        - destination:
            host: nginx.example.com
            port:
              number: 443
          weight: 100
    ---
    apiVersion: networking.istio.io/v1alpha3
    kind: DestinationRule
    metadata:
      name: originate-mtls-for-nginx
    spec:
      host: nginx.example.com
      trafficPolicy:
        loadBalancer:
          simple: ROUND_ROBIN
        portLevelSettings:
        - port:
            number: 443
          tls:
            mode: MUTUAL
            clientCertificate: /etc/nginx-client-certs/tls.crt
            privateKey: /etc/nginx-client-certs/tls.key
            caCertificates: /etc/nginx-ca-certs/ca-chain.cert.pem
            sni: nginx.example.com
    EOF
    
  3. 发送一个 HTTP 请求至 http://nginx.example.com

    $ kubectl exec -it $SOURCE_POD -c sleep -- curl -s --resolve nginx.example.com:80:1.1.1.1 http://nginx.example.com
    <!DOCTYPE html>
    <html>
    <head>
    <title>Welcome to nginx!</title>
    ...
    
  4. 检查 istio-egressgateway pod 日志,有一行与请求相关的日志记录。 如果 Istio 部署在命名空间 istio-system 中,打印日志的命令为:

    $ kubectl logs -l istio=egressgateway -n istio-system | grep 'nginx.example.com' | grep HTTP
    

    将显示类似如下的一行:

    [2018-08-19T18:20:40.096Z] "GET / HTTP/1.1" 200 - 0 612 7 5 "172.30.146.114" "curl/7.35.0" "b942b587-fac2-9756-8ec6-303561356204" "nginx.example.com" "172.21.72.197:443"
    

清除双向 TLS 连接示例

  1. 删除创建的 Kubernetes 资源:

    $ kubectl delete secret nginx-server-certs nginx-ca-certs -n mesh-external
    $ kubectl delete secret nginx-client-certs nginx-ca-certs
    $ kubectl delete secret nginx-client-certs nginx-ca-certs -n istio-system
    $ kubectl delete configmap nginx-configmap -n mesh-external
    $ kubectl delete service my-nginx -n mesh-external
    $ kubectl delete deployment my-nginx -n mesh-external
    $ kubectl delete namespace mesh-external
    $ kubectl delete gateway istio-egressgateway
    $ kubectl delete serviceentry nginx
    $ kubectl delete virtualservice direct-nginx-through-egress-gateway
    $ kubectl delete destinationrule originate-mtls-for-nginx
    $ kubectl delete destinationrule egressgateway-for-nginx
    
  2. 删除用于生成证书和仓库的路径:

    $ rm -rf nginx.example.com mtls-go-example
    
  3. 删除生成并应用于示例中的配置文件

    $ rm -f ./nginx.conf ./istio-egressgateway.yaml
    

清除

删除 sleep 服务和部署:

$ kubectl delete service sleep
$ kubectl delete deployment sleep
这些信息有用吗?
Do you have any suggestions for improvement?

Thanks for your feedback!