【BUG】服务器 v2ray_simple grpc 时，部分终端无法通过代理连上 ssh

[5l2]

环境

• 服务器系统：debian 11
• 服务器应用：verysimple v1.2.5 docker
• 客户端系统：windows 11
• 客户端应用：clash premium 2022.11.25
• 终端：mobaxterm
• ssh 服务器：公网任意

描述

使用 v2ray_simple 作为代理服务器且协议为 trojan+grpc+tls 时，部分终端（如 mobaxterm）通过代理连接 ssh 会卡在终端画面（光标原地闪烁），无法登录。

作为实验，部署 v2ray/hysteria/naiveproxy 等不同应用、为 v2ray_simple 增加 vmess+ws+tls+cdn 的协议组合，接着使用 clash 的 tunnel 功能通过前述代理将服务器 ssh 端口映射到本地不同端口，最后使用 nc/telnet 连接这些本地端口。现象如下。

组 1（对照）：无代理直连服务器 ssh 端口

使用 nc/telnet 直连服务器 ssh 端口，会打印版本信息。如：

SSH-2.0-OpenSSH_8.4p1 Debian-5+deb11u1

组 2：使用 hysteria/naiveproxy 作为代理服务器

使用 nc/telnet 连接映射后的本地端口，会打印版本信息。

组 3：使用 v2ray 作为代理服务器，协议为 trojan+grpc+tls

使用 nc/telnet 连接映射后的本地端口，会打印版本信息。

组 4：使用 v2ray_simple 作为代理服务器，协议为 vmess+ws+tls+cdn

使用 nc/telnet 连接映射后的本地端口，会打印版本信息。

组 5：使用 v2ray_simple 作为代理服务器，协议为 trojan+grpc+tls

使用 nc/telnet 连接映射后的本地端口，卡在终端画面（光标原地闪烁），不打印任何字符。

经测试发现，若在卡住时键入任何按键，则又会打印版本信息。

如何复现

1. 搭建 web 服务器作为反向代理。

2. 搭建 v2ray_simple，协议为 trojan+grpc。

   cat vs_config.toml

   
   [app]
   loglevel = 2
   logfile = "/var/log/verysimple/error.log"
   default_uuid = ************
   [[listen]]
   protocol = "trojan"
   #uuid = ************
   users = ************
   ip = "[::1]"
   port = 8080
   adv = "grpc"
   path = "string"
   [[dial]]
   protocol = "direct"
   fullcone = false
   

3. 安装 clash 客户端。

   cat clash.yaml

   
     - name: clash
       server: 233.252.0.1
       port: 443
       type: trojan
       password: ************
       network: grpc
       sni: example.org
       skip-cert-verify: false
       udp: true
       grpc-opts:
         grpc-service-name: "string"
   

4. 安装 mobaxterm，新建 ssh 连接，配置使用代理。

5. 登录 ssh。

日志

v2ray_simple debug 级日志

cat error.log

{"L":"WARN ","T":"230129 160942.072","M":"Failed in reading first payload, not because of timeout, will hung up","connid":852675,"target":"233.252.0.1:22","error":"EOF"}
{"L":"WARN ","T":"230129 161008.953","M":"Failed in reading first payload, not because of timeout, will hung up","connid":852675,"target":"233.252.0.1:22","error":"EOF"}
{"L":"INFO ","T":"230129 161038.471","M":"Program started","loglvl":0}
{"L":"INFO ","T":"230129 161038.473","M":"zap log init complete.","logfile":"/var/log/verysimple/error.log"}
{"L":"INFO ","T":"230129 161038.473","M":"verysimple [ commit: ff93818, all_go_files_md5: ************  -, tags: ], go1.19.4 linux amd64, with advLayer packages: [quic grpcSimple ws] \n"}
{"L":"INFO ","T":"230129 161038.474","M":"Working at","dir":"/"}
{"L":"DEBUG","T":"230129 161038.474","M":"All Given Flags","flags":{"c":"my string representation"}}
{"L":"INFO ","T":"230129 161038.476","M":"Options","Log Level":"debug","UseReadv":true}
{"L":"INFO ","T":"230129 161038.478","M":"Starting..."}
{"L":"INFO ","T":"230129 161038.479","M":"Listening","tag":"","protocol":"grpc+trojan","listen_addr":"[::1]:8080","defaultClient":"dual+direct","dial_addr":""}
{"L":"INFO ","T":"230129 161041.230","M":"New Accepted Conn","connid":816535,"from":"[::1]:45754","handler":"grpc+trojan://[::1]:8080/string"}
{"L":"DEBUG","T":"230129 161124.585","M":"Default Route","connid":816535,"source":"233.252.0.1:22","client":"dual+direct","addr":""}
{"L":"INFO ","T":"230129 161124.588","M":"Request","connid":816535,"From":"[::1]:45754","Target":"tcp://233.252.0.1:22","through":"dual+direct://"}
{"L":"DEBUG","T":"230129 161124.588","M":"handshake client with first payload","connid":816535,"len":1}
{"L":"DEBUG","T":"230129 161124.849","M":"TryCopy","id":816535,"from":"*net.TCPConn","->":"*trojan.UserTCPConn"}
{"L":"DEBUG","T":"230129 161124.852","M":"copying with readv","id":816535}
{"L":"DEBUG","T":"230129 161124.851","M":"TryCopy","id":816535,"from":"*trojan.UserTCPConn","->":"*net.TCPConn"}
{"L":"DEBUG","T":"230129 161124.853","M":"copying with classic method","id":816535}
{"L":"DEBUG","T":"230129 161126.640","M":"Relay End","id":816535,"direction":"R->L","target":"233.252.0.1:22","bytes":76,"error":"EOF"}
{"L":"DEBUG","T":"230129 161126.643","M":"Relay End","id":816535,"direction":"L->R","target":"233.252.0.1:22","bytes":2,"error":"readfrom tcp 233.252.0.2:48854->233.252.0.1:22: body closed by handler"}

解决

经研究发现，若将 mobaxterm 等终端的协议版本由 auto 变更为 SSHv2 可解决 v2ray_simple 使用 trojan+grpc+tls 时无法通过代理连上 ssh 的问题。此时可正常登录。

但是，此方案不能解决使用 nc/telnet 连接 ssh 映射后的本地端口，不打印版本信息的问题。

[5l2]

应该是 v2ray_simple 读取 first payload 的机制导致了以上 nc/telnet 的现象？

[e1732a364fed]

有可能，需详查

[lw4free]

应该还是grpc服务器端的bug没有完全修复
#159 (comment)

[e1732a364fed]

在vs的 grpc server 收到grpc握手后，确实，如果客户端没发任何信息，就会陷入等待中.

我看了一下代码，忘 Flush了。

[e1732a364fed]

我在最新代码里加了 flush, 请你用最新代码编译并再试一次，然后看看如何

[5l2]

已按组 5 条件测试，依旧不打印 ssh 服务器版本信息。

执行的编译命令：

sudo snap install go --classic
git clone https://github.com/e1732a364fed/v2ray_simple
cd v2ray_simple/cmd/verysimple/
go build

./verysimple -v:

verysimple [version_undefined], go1.19.5 linux amd64, with advLayer packages: [quic grpcSimple ws]

[HeXis-YS]

虽然没有经过严格的测试，但是在我的配置（从gRPC回落到TCP）下也会有类似的行为。