gcmd

A command-line wrapper written in Go to avoid commonly used one-liners.

Inspired by @tomnomnom 's gf

Why?

When doing recon and dealing with large amounts of data, I often end up with complex commands. For example I use httpx to probe for hosts like this

$ echo hackerone.com | httpx -silent -json -response-in-json -o data.json

Full output of this command is here

To get only the HTTP response of the host from this file I use

$ cat data.json | jq -r .serverResponse | sed "s/\\\r\\\n/\\n/g"

It's easy to mess up commands like this especially when having complex Regex patterns.

With gcmd you can give names to command combinations and reuse them anytime.

Saving this command is easy as

$ gcmd -save -i httpx-response 'jq -r .serverResponse | sed "s/\\\r\\\n/\\n/g"'

Now I can use it as

$ cat data.json | gcmd httpx-response

Installation

gcmd requires Go

$ go get -v github.com/arjunshibu/gcmd

Usage

$ gcmd -h

This will show help for the tool. Available switches are

Flag	Description	Example
-ls	List available commands	gcmd -ls
-save	Save a command	gcmd -save test-cmd 'cat /etc/passwd | grep root'
-i	Take input from stdin (for -save only)	gcmd -save -i test-cmd 'sort -u | wc -l'
-echo	Prints the command rather than executing it	gcmd -echo test-cmd
-rm	Remove a command	gcmd -rm test-cmd

Command Files

You can create config directory as ~/.config/gcmd or ~/.gcmd

Command files are stored as JSON files like this

$ cat ~/.gcmd/httpx-response.json
{
   "cmds": [
      {
         "name": "jq",
         "args": ".serverResponse"
      },
      {
         "name": "sed",
         "args": "'s/\\\\r\\\\n/\\n/g'"
      }
   ],
   "stdin": true
}

Some example command files are available in examples directory. Copy them to your config directory.

$ cp -r ~/go/src/github.com/arjunshibu/gcmd/examples ~/.gcmd

Auto Completion

Tab autocompletion scripts for bash and zsh are included. So you can hit Tab to show your commands.

$ gcmd <TAB>
httpx-response       test-cmd

Bash

Place this in ~/.bashrc

source ~/go/src/github.com/arjunshibu/gcmd/autocompletion/gcmd.bash

Zsh

Enable autocomplete if haven't done (no need if you have oh-my-zsh) by placing in ~/.zshrc

autoload -U compaudit && compinit

Place this in ~/.zshrc

source ~/go/src/github.com/arjunshibu/gcmd/autocompletion/gcmd.zsh

Issues

When saving commands, seperate pipes with whitespaces like find . | wc -l instead of find .|wc -l because if you do so, it will get saved as

{
   "cmds": [
      {
         "name": "find",
         "args": ".|cat|wc -l"
      }
   ]
}

This may not be a problem, but avoid it.

gcmd cannot run commands in background. Eg: vim &, because it run commands as bash -c "command".

Contribution

Pull requests are always welcome. Feel free to contribute your ideas or bug fixes ❤️.