cloudflare-zero-trust

Cloudflare Zero Trust

使用 Cloudflare 的 Zero Trust 平台（Access、Tunnel、Gateway 和 WARP），无需 VPN 即可安全访问内部服务。

适用场景

• 替代 VPN，访问内部 Web 应用、SSH 或 RDP。
• 对内部工具（仪表板、管理面板）实施基于身份的访问策略。
• 安全地向远程团队开放本地部署或专用网络中的服务。
• 过滤 DNS 流量，阻止恶意软件、网络钓鱼和影子 IT。
• 强制执行设备状态检查（受管设备、OS 版本、磁盘加密）。

前提条件

• Cloudflare 账户，并开通 Zero Trust 套餐（免费层最多支持 50 位用户）。
• 在 Cloudflare 上托管的域名（用于 Access 应用主机名）。
• 已配置身份提供商（Google Workspace、Okta、Azure AD/Entra ID、GitHub）。
• 在托管内部服务的服务器上安装 cloudflared CLI。

# Install cloudflared
# macOS
brew install cloudflared

# Debian/Ubuntu
curl -fsSL https://pkg.cloudflare.com/cloudflare-main.gpg | sudo tee /usr/share/keyrings/cloudflare-main.gpg >/dev/null
echo "deb [signed-by=/usr/share/keyrings/cloudflare-main.gpg] https://pkg.cloudflare.com/cloudflared $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/cloudflared.list
sudo apt update && sudo apt install -y cloudflared

# Docker
docker pull cloudflare/cloudflared:latest

Cloudflare Tunnel 设置

Tunnel 会在你的基础设施与 Cloudflare 边缘之间建立加密的出站连接，无需开放入站端口。

创建和配置 Tunnel

# Authenticate with Cloudflare
cloudflared tunnel login

# Create a named tunnel
cloudflared tunnel create internal-apps

# This creates credentials at ~/.cloudflared/<TUNNEL_ID>.json

# List tunnels
cloudflared tunnel list

# Route DNS to the tunnel (creates a CNAME record)
cloudflared tunnel route dns internal-apps grafana.example.com
cloudflared tunnel route dns internal-apps wiki.example.com
cloudflared tunnel route dns internal-apps ssh.example.com

Tunnel 配置文件

# ~/.cloudflared/config.yml
tunnel: <TUNNEL_ID>
credentials-file: /home/deploy/.cloudflared/<TUNNEL_ID>.json

ingress:
  # Grafana dashboard
  - hostname: grafana.example.com
    service: http://localhost:3000

  # Internal wiki
  - hostname: wiki.example.com
    service: http://localhost:8080
    originRequest:
      noTLSVerify: true

  # SSH access via browser
  - hostname: ssh.example.com
    service: ssh://localhost:22

  # Private network access (CIDR routing)
  - hostname: internal.example.com
    service: http://10.0.0.0/24

  # Catch-all — required as the last rule
  - service: http_status:404

运行 Tunnel

# Run in foreground (for testing)
cloudflared tunnel run internal-apps

# Install as a systemd service
sudo cloudflared service install
sudo systemctl enable cloudflared
sudo systemctl start cloudflared

# Or run via Docker
docker run -d --name cloudflared \
  --restart unless-stopped \
  -v /home/deploy/.cloudflared:/etc/cloudflared \
  cloudflare/cloudflared:latest \
  tunnel run internal-apps

使用 Tunnel 的 Docker Compose

# docker-compose.yml
version: "3.8"
services:
  cloudflared:
    image: cloudflare/cloudflared:latest
    restart: unless-stopped
    command: tunnel run
    environment:
      - TUNNEL_TOKEN=${TUNNEL_TOKEN}
    networks:
      - internal

  grafana:
    image: grafana/grafana:latest
    networks:
      - internal

  wiki:
    image: requarks/wiki:2
    networks:
      - internal

networks:
  internal:
    driver: bridge

Access 策略

Access 策略用于控制谁可以访问 Cloudflare 后方的应用。

创建 Access 应用

# Via API — create a self-hosted application
curl -X POST "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/access/apps" \
  -H "Authorization: Bearer $CF_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Grafana",
    "domain": "grafana.example.com",
    "type": "self_hosted",
    "session_duration": "12h",
    "auto_redirect_to_identity": true,
    "allowed_idps": ["<IDP_UUID>"]
  }'

策略类型和示例

# Allow policy — members of the engineering group
curl -X POST "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/access/apps/<APP_ID>/policies" \
  -H "Authorization: Bearer $CF_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Engineering Team",
    "decision": "allow",
    "include": [
      { "group": { "id": "<GROUP_UUID>" } }
    ],
    "require": [
      { "login_method": { "id": "<MFA_METHOD_UUID>" } }
    ]
  }'

常见策略模式

模式	包含规则	要求规则
所有员工	电子邮件域 @company.com	-
仅限工程团队	Access 组“Engineering”	MFA
承包商（限时）	电子邮件列表	设备状态
CI/CD 自动化	服务令牌	-
外部合作伙伴	指定电子邮件	国家/地区检查

用于自动化的服务令牌

# Create a service token for CI/CD
curl -X POST "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/access/service_tokens" \
  -H "Authorization: Bearer $CF_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"name": "github-actions-deploy"}'

# Response includes Client ID and Client Secret
# Use in CI with headers:
# CF-Access-Client-Id: <CLIENT_ID>
# CF-Access-Client-Secret: <CLIENT_SECRET>

# Use service token in CI/CD
curl -H "CF-Access-Client-Id: $CF_CLIENT_ID" \
     -H "CF-Access-Client-Secret: $CF_CLIENT_SECRET" \
     https://grafana.example.com/api/health

设备状态检查

在授予访问权限前强制检查终端设备是否符合要求。

配置状态检查（控制面板）

1. 前往 Settings > WARP Client > Device posture。
2. 添加检查项：
   • 磁盘加密：要求启用 FileVault（macOS）或 BitLocker（Windows）。
   • OS 版本：最低要求为 macOS 14.0 或 Windows 11。
   • 防火墙：确保已启用主机防火墙。
   • Crowdstrike/SentinelOne：确认 EDR Agent 正在运行。
3. 在 Access 策略的 Require 规则中引用状态检查。

Gateway DNS 过滤

在 DNS 层阻止恶意域名并强制执行可接受使用策略。

DNS 位置

# Configure DNS endpoints for offices or networks
# Dashboard: Gateway > DNS Locations > Add a location
# Assign the Gateway DNS IPs to your network's DNS resolver:
# IPv4: 172.64.36.1, 172.64.36.2
# IPv6: 2606:4700:4700::1111
# DoH: https://<UNIQUE_ID>.cloudflare-gateway.com/dns-query

DNS 策略

# Create a DNS policy to block malware and phishing
curl -X POST "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/gateway/rules" \
  -H "Authorization: Bearer $CF_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Block Security Threats",
    "enabled": true,
    "action": "block",
    "traffic": "any(dns.security_category[*] in {80 83 131 134 151 153})",
    "filters": ["dns"]
  }'

常见 DNS 策略规则

规则名称	流量表达式	操作
阻止恶意软件	any(dns.security_category[*] in {80 83})	阻止
阻止网络钓鱼	any(dns.security_category[*] in {131 134})	阻止
阻止社交媒体	any(dns.content_category[*] in {75})	阻止
允许例外	dns.fqdn == "allowed.example.com"	允许

WARP 客户端部署

部署 Cloudflare WARP 客户端，通过 Gateway 路由流量。

# MDM deployment — macOS configuration profile
# Use Cloudflare's managed deployment:
# Dashboard: Settings > WARP Client > Device enrollment

# Manual enrollment
# 1. Install WARP client from https://1.1.1.1
# 2. Click gear icon > Account > Login with Cloudflare Zero Trust
# 3. Enter your team name (from Settings > General)

# Verify WARP is connected
curl https://connectivity.cloudflare.com/cdn-cgi/trace
# Look for: warp=on

WARP 分流隧道

# Configure split tunnels to exclude certain traffic from WARP
# Dashboard: Settings > WARP Client > Device settings > Split Tunnels

# Exclude mode (default): WARP handles everything except listed IPs
# Include mode: WARP only handles listed IPs/domains

# Common exclusions:
# - Local network: 192.168.0.0/16, 10.0.0.0/8
# - Video conferencing: zoom.us, *.teams.microsoft.com
# - Printer subnets

SSH 和基于浏览器的终端

# In cloudflared config.yml — expose SSH via browser rendering
ingress:
  - hostname: ssh.example.com
    service: ssh://localhost:22

# Users access ssh.example.com in their browser
# Cloudflare renders an in-browser terminal after Access authentication

# Or use cloudflared on the client side for native SSH
cloudflared access ssh --hostname ssh.example.com

# Add to SSH config for seamless access
# ~/.ssh/config
# Host ssh.example.com
#   ProxyCommand /usr/local/bin/cloudflared access ssh --hostname %h

故障排查

症状	原因	修复方法
隧道在仪表板中显示 ERR	cloudflared 未运行或配置有误	检查 systemctl status cloudflared；验证配置 YAML
身份正确但访问仍返回 403	策略顺序有误或缺少 require 规则	策略按从上到下的顺序评估；确保 Allow 位于 Block 上方
WARP 显示“无法连接”	团队名称错误或已禁用注册	在 Settings > General 中验证团队名称；检查注册权限
服务令牌身份验证失败	令牌已过期或请求头错误	重新生成令牌；同时使用 CF-Access-Client-Id 和 CF-Access-Client-Secret
DNS 过滤未生效	客户端未使用 Gateway DNS 解析器	确认 DNS 设置为 172.64.36.1；检查 WARP 是否已连接
隧道延迟激增	隧道运行在负载过高的主机上	监控 cloudflared 的资源使用情况；在专用基础设施上运行
“没有健康的源站”错误	后端服务已停止	检查配置的 ingress 端口上的服务；查看 cloudflared 日志

相关技能

• cloudflare-workers - Access 策略背后的边缘计算
• dns-management - DNS 路由和记录管理
• reverse-proxy - 替代网关模式
• service-mesh - 服务间内部安全