firstgold/.agents/skills/sysadmin-toolbox/references/shell-tricks.md

Shell Tricks  ^[TOC]

When you get a shell, it is generally not very clean, but after following these steps, you will have a fairly clean and comfortable shell to work with.

1. script /dev/null -c bash
2. Ctrl-Z (to send it to background)
3. stty raw -echo; fg (returns the shell to foreground)
4. reset (to reset terminal)
5. xterm (when asked for terminal type)
6. export TERM=xterm; export SHELL=bash

Shell functions  ^[TOC]

Table of Contents

• Domain resolve
• Get ASN

Domain resolve

# Dependencies:
#   - curl
#   - jq

function DomainResolve() {

  local _host="$1"

  local _curl_base="curl --request GET"
  local _timeout="15"

  _host_ip=$($_curl_base -ks -m "$_timeout" "https://dns.google.com/resolve?name=${_host}&type=A" | \
  jq '.Answer[0].data' | tr -d "\"" 2>/dev/null)

  if [[ -z "$_host_ip" ]] || [[ "$_host_ip" == "null" ]] ; then

    echo -en "Unsuccessful domain name resolution.\\n"

  else

    echo -en "$_host > $_host_ip\\n"

  fi

}

Example:

shell> DomainResolve nmap.org
nmap.org > 45.33.49.119

shell> DomainResolve nmap.org
Unsuccessful domain name resolution.

Get ASN

# Dependencies:
#   - curl

function GetASN() {

  local _ip="$1"

  local _curl_base="curl --request GET"
  local _timeout="15"

  _asn=$($_curl_base -ks -m "$_timeout" "http://ip-api.com/line/${_ip}?fields=as")

  _state=$(echo $?)

  if [[ -z "$_ip" ]] || [[ "$_ip" == "null" ]] || [[ "$_state" -ne 0 ]]; then

    echo -en "Unsuccessful ASN gathering.\\n"

  else

    echo -en "$_ip > $_asn\\n"

  fi

}

Example:

shell> GetASN 1.1.1.1
1.1.1.1 > AS13335 Cloudflare, Inc.

shell> GetASN 0.0.0.0
Unsuccessful ASN gathering.