frpc客户端不能通过X-Forwarded-For获取到 realip

[acmookey]

Bug Description

• 网络结构
  外网Nginx <=> frps <=> 内网frpc
• 问题描述
  保持以上网络结构以及配置不变的情况下，在0.55.1和 目前最新版本0.56.0的frpc客户端中，使用 X-Forwarded-For不能获取到客户端IP。tcp报文见 logs部分

frpc Version

0.55.1

frps Version

0.55.1

System Architecture

linux/arm64

Configurations

• 外网Nginx

map $http_upgrade $connection_upgrade {
  default upgrade;
  ''      close;
}
server {
  listen 443 ssl http2;
  server_name umami.test.com;

  include tls/_.test.conf;

  location / {
    proxy_pass http://127.0.0.1:9999;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;

    proxy_http_version 1.1;
    proxy_set_header   Upgrade $http_upgrade;
    proxy_set_header   Connection $connection_upgrade;

    proxy_connect_timeout 3m;
    proxy_send_timeout 3m;
    proxy_read_timeout 3m;

    client_max_body_size 0; # Stream request body to backend

    proxy_buffering off;
    proxy_request_buffering off;
    proxy_redirect off;
  }
}

• frps.toml

vhostHTTPPort    = 9999

• frpc.toml

[[proxies]]
name      = "umami"
type      = "http"
localPort = 8092
customDomains = ["umami.test.com"]

Logs

使用tcpdump抓取了frpc客户端所在机器中 8092 端口TCP报文

tcpdump -i lo -n  tcp port 8092 -XXvvvnn -s0

不同版本的frp报文如下：

• frps: 0.54.0 frpc: 0.54.0

	0x0280:  2d53 6974 653a 2073 616d 652d 7369 7465  -Site:.same-site
	0x0290:  0d0a 582d 466f 7277 6172 6465 642d 466f  ..X-Forwarded-Fo
	0x02a0:  723a 2031 3230 2e32 3330 2e38 302e 3730  r:.120.230.80.70
	0x02b0:  2c20 3132 372e 302e 302e 310d 0a58 2d46  ,.127.0.0.1..X-F

• frps: 0.55.1 frpc: 0.55.1

	0x0280:  2d53 6974 653a 2073 616d 652d 7369 7465  -Site:.same-site
	0x0290:  0d0a 582d 466f 7277 6172 6465 642d 466f  ..X-Forwarded-Fo
	0x02a0:  723a 2031 3237 2e30 2e30 2e31 0d0a 582d  r:.127.0.0.1..X-

• frps: 0.56.0 frpc: 0.56.0

	0x0280:  2d53 6974 653a 2073 616d 652d 7369 7465  -Site:.same-site
	0x0290:  0d0a 582d 466f 7277 6172 6465 642d 466f  ..X-Forwarded-Fo
	0x02a0:  723a 2031 3237 2e30 2e30 2e31 0d0a 582d  r:.127.0.0.1..X-

Steps to reproduce

1、将frps以及frpc 从0.54.0版本升级到 0.55.1版本，访问代理服务时通过tcpdump抓取报文发现 X-Forwarded-For相较0.54.0版本缺少了客户端真实ip 120.230.80.70
2、当前最新版本 0.56.0也存在该问题

Affected area

• Docs
• Installation
• Performance and Scalability
• Security
• User Experience
• Test and Release
• Developer Infrastructure
• Client Plugin
• Server Plugin
• Extensions
• Others