国密SSL/TLS双证书自适应方案详解

客户端                          服务器
  |                              |
  |--- ClientHello ------------->|
  |  (包含supported_groups,     |
  |   signature_algorithms,     |
  |   key_share扩展)            |
  |                              |
  |  检测客户端能力:             |
  |  - 是否支持TLS_GM扩展?      |
  |  - 是否支持SM2签名算法?     |
  |  - Client UA是否为国密浏览器?|
  |                              |
  |<-- ServerHello -------------|
  |  (选择密码套件):            |
  |  - 国密: TLS_SM4_GCM_SM3   |
  |  - 国际: TLS_AES_256_GCM_SHA384 |
  |  (返回对应证书):            |
  |  - 国密: SM2服务器证书       |
  |  - 国际: RSA/ECC服务器证书   |
  |                              |
  |--- Certificate ------------>|
  |--- ServerKeyExchange ------>|
  |--- CertificateRequest ----->| (可选，双向认证)
  |--- ServerHelloDone -------->|
  |                              |
  |--- ClientKeyExchange ------->|
  |--- CertificateVerify ------>| (如有客户端证书)
  |--- Finished --------------->|
  |                              |
  |<-- Finished ----------------|
  |                              |
  [TLS连接建立，使用协商的密码套件]

# ⚠️ 环境要求：需编译Tongsuo或BabaSSL国密版Nginx
server {
    listen 443 ssl;
    server_name example.com;

    # --- 国际证书（默认，兼容所有浏览器）---
    ssl_certificate     /etc/nginx/ssl/intl-cert.pem;
    ssl_certificate_key /etc/nginx/ssl/intl-key.pem;

    # --- 国密证书（国密浏览器自动协商）---
    # Tongsuo/Nginx国密版通过ssl_gmtls指令启用
    ssl_gmtls_certificate     /etc/nginx/ssl/gm-cert.pem;
    ssl_gmtls_certificate_key /etc/nginx/ssl/gm-key.pem;

    # --- 国际密码套件（从高到低排序）---
    ssl_ciphers ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305;
    ssl_prefer_server_ciphers on;

    # --- 国密密码套件 ---
    ssl_gmtls_ciphers TLS_SM4_GCM_SM3;
    ssl_gmtls_prefer_server_ciphers on;

    # --- 椭圆曲线 ---
    ssl_ecdh_curve secp256r1:x25519;
    # 国密SM2曲线由gmssl库内置定义

    # --- 会话缓存 ---
    ssl_session_cache shared:SSL:10m;
    ssl_session_timeout 1d;
    ssl_session_tickets off;

    # --- HSTS ---
    add_header Strict-Transport-Security "max-age=63072000" always;

    location / {
        proxy_pass http://backend;
    }
}

# ⚠️ 环境要求：需编译Tongsuo版HAProxy
# 标准HAProxy不支持国密TLS

global
    ssl-default-bind-options no-sslv3 tlsv12
    ssl-default-bind-ciphers ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384

frontend gm_https
    bind *:443 ssl crt /etc/haproxy/certs/
    bind *:443 ssl crt /etc/haproxy/certs/gm.pem alpn h2,http/1.1 gmtls

    # 国密证书优先匹配
    acl is_gm_browser ssl_ocsp_mbu -m str 1
    use_backend gm_servers if is_gm_browser
    default_backend intl_servers

backend gm_servers
    server gm1 10.0.1.10:443 check ssl verify none
    server gm2 10.0.1.11:443 check ssl verify none

backend intl_servers
    server intl1 10.0.2.10:443 check ssl verify none
    server intl2 10.0.2.11:443 check ssl verify none

客户端 → CDN边缘节点 → 源站
              │
         ┌────┴────┐
         │ 智能路由 │
         └────┬────┘
       ┌──────┴──────┐
       ▼             ▼
  国密证书路径    国际证书路径
  (SM2+SM4+SM3)  (RSA+AES+SHA)
       │             │
       └──────┬──────┘
              ▼
         后端应用服务器