前言⌗

可能是之前无论是 NPM 还是 Composer 又或者是 Homebrew 在安装所需要的包时，我都会通过环境变量设置代理，来提升下载的速度。我潜意识里就觉得 ALL_PROXY 这个环境变量可能是所有协议都会用这个代理。

但是当我使用 git clone [email protected]:u-boot/u-boot.git 克隆项目时，我发现很长时间并没有任何反应，再一看 Surge 的流量监控，没有流量经过，那应该是没有走我设置的 ALL_PROXY。

经过一番面向搜索引擎学习，发现 Git 支持的协议有下面三种：

HTTP
SSH
Git Protocol

误区⌗

看到网上很多的教程都说的是在 ~/.gitconfig 文件中配置 http 和 https 的代理：

[http "https://github.com/"]
    proxy = http://<host>:<port>/
[https "https://github.com/"]
    proxy = https://<host>:<port>/

又或者是通过下面的命令设置代理：

git config --global http.proxy http://username:[email protected]:8080
git config --global https.proxy http://username:[email protected]:8080

或者是像我之前使用的使用临时环境变量：

export https_proxy=http://127.0.0.1:8234;export http_proxy=http://127.0.0.1:8234;export all_proxy=socks5://127.0.0.1:8235

注意：这种方式只针对使用 HTTP 协议的才有效！如果你在 clone 的时候使用的是 SSH 协议，这些设置并不能起到什么作用。

配置 SSH 代理⌗

与在之前的《使用 ClashX 为 SSH 加速》文中一样，我们只需要在 ~/.ssh/config 文件中添加如下配置：

Host github.com
    User git
    ProxyCommand nc -x 127.0.0.1:8235 -X 5 %h %p

设置好以后，就可以测试使用 SSH 的方式从 Github 上克隆项目了。

对于使用 gh ¹ 的开发者来说，如果使用的是 SSH 协议，那么也是一样的。

gh repo clone u-boot/u-boot

Github CLI clone iTerm 2 tasks

Git Protocol⌗

本来没打算写关于 Git Protocol 的部分，因为很少用单，但是在学习操作系统的时候需要安装 riscv-tools，于是照着 6.S081: Operating System Engineering 的步骤安装，但是发现在克隆 glibc 的源码时因为网络原因，卡主不动了。看了下日志，这个项目仓库的地址是 git://sourceware.org/git/glibc.git。

期初没认出来这个是 Git Protocol，我按照 SSH 的方法在配置文件中设置了 sourceware.org 的代理，但是发现并没有生效，然后琢磨了半天，发现这个不是 SSH 协议。

既然找到问题了，那就好解决了，首先需要创建一个 git-proxy 脚本：

#! /bin/bash

# connect to the Git repository through a SOCKS proxy


# default setting is to use port 1080 on the local host
proxy="localhost:1080"
from="default"

# check if there is a value in the git configuration
if git config --get socks.proxy >& /dev/null; then
    proxy=`git config --get socks.proxy`
    from="git's socks.proxy"
fi

# check if a generic proxy has been defined in the environment
if [ -n "$ALL_PROXY" ]; then
    proxy="$ALL_PROXY"
    from="\$ALL_PROXY"
fi
if [ -n "$all_proxy" ]; then
    proxy="$all_proxy"
    from="\$all_proxy"
fi

# check if a SOCKS proxy has been defined in the environment
if [ -n "$SOCKS_PROXY" ]; then
    proxy="$SOCKS_PROXY"
    from="\$SOCKS_PROXY"
fi
if [ -n "$socks_proxy" ]; then
    proxy="$socks_proxy"
    from="\$socks_proxy"
fi
if [ -n "$SOCKS5_PROXY" ]; then
    proxy="$SOCKS5_PROXY"
    from="\$SOCKS5_PROXY"
fi
if [ -n "$socks5_proxy" ]; then
    proxy="$socks5_proxy"
    from="\$socks5_proxy"
fi

# check if a git specific SOCKS proxy has been defined in the environment
if [ -n "$GIT_SOCKS_PROXY" ]; then
    proxy="$GIT_SOCKS_PROXY"
    from="\$GIT_SOCKS_PROXY"
fi

function usage() {
cat << @EOF
Usage:
  `basename $0` HOST PORT

Helper script to connect to a Git repository over the git:// protocol at host HOST and port PORT through a SOCKS proxy at $proxy ($from).

To use the proxy for all git:// traffic, set the core.gitproxy option to "git-proxy":

  git config core.gitproxy "git-proxy"


To use the proxy only for some reporitories, use the syntax explained in git-config(1).

To configure which proxy to use, set an appropriate environment variable (see below) or socks.proxy option to the proxy address, for example "localhost:1080":

  git config socks.proxy "localhost:1080"


The address of the proxy is read from (in order of priority):
  - the GIT_SOCKS_PROXY environment variable;
  - the SOCKS_PROXY or SOCKS5_PROXY environment variable;
  - the ALL_PROXY environment variable (see curl(1));
  - the socks.proxy git option;
  - the default value: localhost:1080 .
@EOF
}

if [ -z "$1" ] || [ -z "$2" ] || [ -n "$3" ]; then
  usage
  exit 1
fi

# connect through the specifid proxy

nc -x "$proxy" "$1" "$2"

将上面的代码保存为脚本，然后保存到你的任意 PATH 目录中，例如我这里是放在了 /usr/local/bin/ 的目录中，命名为：git-proxy，然后执行如下命令，验证是否生效：

git-proxy --help

Usage:
  git-proxy HOST PORT

Helper script to connect to a Git repository over the git:// protocol at host HOST and port PORT through a SOCKS proxy at 127.0.0.1:8235 (git's socks.proxy).

To use the proxy for all git:// traffic, set the core.gitproxy option to "git-proxy":

  git config core.gitproxy "git-proxy"


To use the proxy only for some reporitories, use the syntax explained in git-config(1).

To configure which proxy to use, set an appropriate environment variable (see below) or socks.proxy option to the proxy address, for example "localhost:1080":

  git config socks.proxy "localhost:1080"


The address of the proxy is read from (in order of priority):
  - the GIT_SOCKS_PROXY environment variable;
  - the SOCKS_PROXY or SOCKS5_PROXY environment variable;
  - the ALL_PROXY environment variable (see curl(1));
  - the socks.proxy git option;
  - the default value: localhost:1080 .

接着按照提示执行如下命令：

# 脚本的位置建议使用绝对地址，否则可能出现 error: cannot run git-proxy: No such file or directory.
git config core.gitproxy "/usr/local/bin/git-proxy"
git config socks.proxy "127.0.0.1:8235"

另外因为 Surge 的 Copy Shell Export Command 生成的命令中，存在 export all_proxy=socks5://127.0.0.1:8235 这个环境变量，根据 git-proxy 中的脚本逻辑，可以看到如果设置了 all_proxy 环境变量，将会覆盖掉 Git 的全局配置！！！正式因为这样，才导致我发现了下面的坑。

注意：这里的代理地址不需要加协议类型，直接是 HOST:PORT 这种写法。如过包含协议，如 socks5://127.0.0.1:8235，这种写法会导致 nc: getaddrinfo: nodename nor servname provided, or not known. 从而无法代理 Git Protocol。

然后测试通过 Git Protocol 克隆的流量是否按照预期走我们的 Surge 代理：

brew install riscv-tools
==> Downloading https://ghcr.io/v2/homebrew/core/mpfr/manifests/4.1.0
Already downloaded: /Users/George/Library/Caches/Homebrew/downloads/e8b18e060649c00d9e1e351e3e05515c365e52dbd7bd392e2b99808d1f355b5b--mpfr-4.1.0.bottle_manifest.json
==> Downloading https://ghcr.io/v2/homebrew/core/mpfr/blobs/sha256:81ced499f237acfc2773711a3f8aa985572eaab2344a70485c06f72405e4a5e7
Already downloaded: /Users/George/Library/Caches/Homebrew/downloads/1816ae3e6ff09ea7ad42b8f5ff16142fd0a973c41c5633dfa3b1cf4fa2e1d51b--mpfr--4.1.0.arm64_monterey.bottle.tar.gz
==> Downloading https://ghcr.io/v2/homebrew/core/gawk/manifests/5.1.1
Already downloaded: /Users/George/Library/Caches/Homebrew/downloads/13f45768bf43ccad0a4fabeca4923e0a6836a412b1255585fba6260956e53b70--gawk-5.1.1.bottle_manifest.json
==> Downloading https://ghcr.io/v2/homebrew/core/gawk/blobs/sha256:093465f34b94ec8ddeb4ff8dab2a02dafbccf8ec05f6ef0391673b7c4fd0a91f
Already downloaded: /Users/George/Library/Caches/Homebrew/downloads/0e765b98a270520e3539fb021f555e78705e08b6f24da7e20a56d1f228be9ff1--gawk--5.1.1.arm64_monterey.bottle.tar.gz
==> Downloading https://ghcr.io/v2/homebrew/core/gnu-sed/manifests/4.8
Already downloaded: /Users/George/Library/Caches/Homebrew/downloads/71fd4a7118e6fb954728ce6a8f92871d721711578de17baa01337b3570581179--gnu-sed-4.8.bottle_manifest.json
==> Downloading https://ghcr.io/v2/homebrew/core/gnu-sed/blobs/sha256:78481cc3509f617328d3c361c21beef829f24f4b130cabfc08ed6e4ce83f2286
Already downloaded: /Users/George/Library/Caches/Homebrew/downloads/c0d5ea51ee74ae84aee90d77161075b8567d8c949e99a85582e2fa1570eb824b--gnu-sed--4.8.arm64_monterey.bottle.tar.gz
==> Downloading https://ghcr.io/v2/homebrew/core/isl/manifests/0.24
Already downloaded: /Users/George/Library/Caches/Homebrew/downloads/cf108f3cbdbad48a5ecbe0a148e97b47590045a58151ad768bcf7219ec23305a--isl-0.24.bottle_manifest.json
==> Downloading https://ghcr.io/v2/homebrew/core/isl/blobs/sha256:be08c3e9765655ad5bfd227f9b97acb0ef88ad2307dc214ea4064cc1f51db641
Already downloaded: /Users/George/Library/Caches/Homebrew/downloads/65e4670b48d6dda0e181978e35cf506256f350f33cf7e1371b9451856ad21d41--isl--0.24.arm64_monterey.bottle.tar.gz
==> Downloading https://ghcr.io/v2/homebrew/core/libmpc/manifests/1.2.1
Already downloaded: /Users/George/Library/Caches/Homebrew/downloads/3f193de9dd7f9e68742cf207cfadd3a63b695a8026d343b668e10a9b7bcf6e52--libmpc-1.2.1.bottle_manifest.json
==> Downloading https://ghcr.io/v2/homebrew/core/libmpc/blobs/sha256:658a1d260b6f77c431451a554ef8fa36ea2b6db19b38adc05c52821598ce2647
Already downloaded: /Users/George/Library/Caches/Homebrew/downloads/d18d439506c54ddbad35cc4dc0c77e5fc3fd442c9ec926ff212d6fed1a11c8b6--libmpc--1.2.1.arm64_monterey.bottle.tar.gz
==> Cloning https://github.com/riscv/riscv-gnu-toolchain.git
Updating /Users/George/Library/Caches/Homebrew/riscv-gnu-toolchain--git
==> Checking out branch master
Already on 'master'
Your branch is up to date with 'origin/master'.
HEAD is now at 1342cd7 Merge pull request #1073 from palmer-dabbelt/qemu-system
Entering 'qemu'
Entering 'riscv-binutils'
Entering 'riscv-dejagnu'
Entering 'riscv-gcc'
Entering 'riscv-gdb'
Cloning into '/Users/George/Library/Caches/Homebrew/riscv-gnu-toolchain--git/glibc'...
Cloning into '/Users/George/Library/Caches/Homebrew/riscv-gnu-toolchain--git/musl'...
Cloning into '/Users/George/Library/Caches/Homebrew/riscv-gnu-toolchain--git/newlib'..

ps -ef | grep "nc -x 127.0.0.1:8235" | grep -v grep
  501 53932 53462   0 11:58PM ttys002    0:00.00 nc -x 127.0.0.1:8235 sourceware.org 9418

可以看到，在执行 Homebrew 安装命令的时候，启动了一个 netcat 进程，并通过代理与 sourceware.org 的 9418 端口建立了连接。9418 就是 Git Protocol 所使用的端口！

SSH 协议使用 HTTP 端口进行项目克隆⌗

最近因为速蛙云跑路，不得不更换其他机场。但是更换后发现无法通过 SSH 协议正常克隆 Github 项目，出现如下错误：

gh repo clone golang-module/carbon
Cloning into 'carbon'...
kex_exchange_identification: Connection closed by remote host
Connection closed by UNKNOWN port 65535
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.
exit status 128

询问后得知机场运维人员处于安全考虑禁止了 22 端口的流量，同时也给出了解决方案，在 Github 官方文档中有说明：Using SSH over the HTTPS port。

参照文档我修改了 ~/.ssh/config 的配置：

Host github.com
	User git
	HostName ssh.github.com
	Port 443
	ProxyCommand nc -x 127.0.0.1:8235 -X 5 %h %p

然后就可以正常加速 SSH 协议的 Git 操作了！

I hope this is helpful, Happy hacking…

Github CLI. ↩︎

通过配置 Git Proxy 加速克隆 Github 项目

前言⌗

误区⌗

配置 SSH 代理⌗

Git Protocol⌗

SSH 协议使用 HTTP 端口进行项目克隆⌗