03-26 05:29 阅读 175

TCP四层代理透传客户端真实IP

缘起

最近公司准备自建邮箱，大概十年前折腾过自建邮箱的事情，感觉坑很多，这次体会了下确实很多，特别是现在管局对邮箱端口管控越来越严格的情况下，很多之前能行得通的方案需要修改下。
由于SMTP、POP3、IMAP等协议需要做四层代理且还需要能穿透客户端真实IP，硬件网络层代理软件又不能使用的情况下只能考虑软代理，下面是记录的两种解决方案。

方案

Nginx解决方案

1.注意nginx编译时需要加上stream模块及stream_realip_module模块;一个用来四层负载，一个用来获取客户端真实IP
2.开启透传功能proxy_protocol on，用于将连接信息从请求连接的源传递到请求连接到的目标

具体配置如下

# /usr/local/nginx/sbin/nginx -Vnginx version: nginx/1.16.1built by gcc 4.8.5 20150623 (Red Hat 4.8.5-44) (GCC)
built with OpenSSL 1.0.2k-fips  26 Jan 2017TLS SNI support enabled
configure arguments: --prefix=/usr/local/nginx  --with-stream --with-stream_realip_module# cat /usr/local/nginx/conf/nginx.confuser  nginx;worker_processes  auto;events {    worker_connections  10240;
    }include tcp/*.conf;# cat /usr/local/nginx/conf/tcp/mail.confstream {    log_format proxy '$remote_addr [$time_local] '
                 '$protocol $status $bytes_sent $bytes_received '
                 '$session_time "$upstream_addr" '
                 '"$upstream_bytes_sent" "$upstream_bytes_received" "$upstream_connect_time"';    access_log /usr/local/nginx/logs/mail.log proxy;    upstream mail_http {        server 192.168.188.88:80 ;
    }    server {        listen 80;        proxy_connect_timeout 10s;        proxy_timeout 30s;        proxy_pass mail_web;
    }    upstream mail_https {        server 192.168.188.88:443 ;
    }    server {        listen 443;        proxy_connect_timeout 10s;        proxy_timeout 30s;        proxy_pass mail_https;
    }    upstream mail_smtp {        server 192.168.188.88:25 ;
    }    server {        listen 25 ;        proxy_connect_timeout 10s;        proxy_timeout 300s;        proxy_protocol on ;        proxy_pass mail_smtp;
    }    upstream mail_smtps {        server 192.168.188.88:465 ;
    }    server {        listen 465;        proxy_connect_timeout 10s;        proxy_timeout 30s;        proxy_protocol on ;        proxy_pass mail_smtps;
    }    upstream mail_pop3 {        server 192.168.188.88:110 ;
    }    server {        listen 110;        proxy_connect_timeout 10s;        proxy_timeout 30s;        proxy_protocol on ;        proxy_pass mail_pop3;
    }    upstream mail_pop3s {        server 192.168.188.88:995 ;
    }    server {        listen 995;        proxy_connect_timeout 10s;        proxy_timeout 30s;        proxy_protocol on ;        proxy_pass mail_pop3s;
    }    upstream mail_imap {        server 192.168.188.88:143 ;
    }    server {        listen 143;        proxy_connect_timeout 10s;        proxy_timeout 30s;        proxy_protocol on ;        proxy_pass mail_imap;
    }    upstream mail_imaps {        server 192.168.188.88:993 ;
    }    server {        listen 993;        proxy_connect_timeout 10s;        proxy_timeout 30s;        proxy_protocol on ;        proxy_pass mail_imaps;
    }

}

Haproxy解决方案

1.开通tcp 模式 mode tcp
2.开启透传 send-proxy
注意：基本上haproxy参数需结合haproxy -c测试，一条条的来过才能确定最终哪个参数起作用

# haproxy -vHA-Proxy version 1.5.18 2016/05/10Copyright 2000-2016 Willy Tarreau <willy@haproxy.org># cat /etc/haproxy/haproxy.cflisten stats
mode http bind 0.0.0.0:9999
stats enable log global
stats uri     /haproxy-status
stats auth    haadmin:yourpasswordlisten WEB    bind 80
    mode http
    server web01 192.168.188.88:80  check

listen WEBSSL    bind 443
    mode tcp
    server webssl01 192.168.188.88:443  check

listen MAIL    bind 25
    mode tcp
    server mail01 192.168.188.88:25  check send-proxylisten MAILS    bind 465
    mode tcp
    server mailssl01 192.168.188.88:465  check send-proxylisten POP3    bind 110
    mode tcp
    server pop301 192.168.188.88:110  check send-proxylisten POP3S    bind 995
    mode tcp
    server pop3ssl01 192.168.188.88:995  check send-proxylisten IMAP    bind 143
    mode tcp
    server imap01 192.168.188.88:143  check send-proxylisten IMAPS    bind 993
    mode tcp
    server imapssl01 192.168.188.88:993  check send-proxy

尾声

当然了，这只是自建邮件服务器其中一个小小的问题，基本上一步一个问题，所以现在自建邮箱越来越少了，基本上都被云邮箱取代了，就连Postfix 2012年的时候都停止更新维护了，估计再后来懂这门手艺的人会越来越少了。