gtfoshell

#!/bin/bash

#Author: DeGr4ne

#Colors

greenColor="\e[0;32m\033[1m"
endColor="\033[0m\e[0m"
redColor="\e[0;31m\033[1m"
blueColor="\e[0;34m\033[1m"
yellowColor="\e[0;33m\033[1m"
purpleColor="\e[0;35m\033[1m"
turquoiseColor="\e[0;36m\033[1m"
grayColor="\e[0;37m\033[1m"

# trap ctrl-c and call ctrl_c()
trap ctrl_c INT

function ctrl_c(){

	echo -e "\n${redColor}[!] Exiting...\n${endColor}"
	tput cnorm
       	rm bins.tmp; exit 1
}

function HelpPanel(){

	echo -e "\n\n"
	echo -e "${blueColor}  ██████╗ ████████╗███████╗ █████╗  ██████╗██╗  ██╗███████╗██╗     ██╗"     
	echo -e "${blueColor} ██╔════╝ ╚══██╔══╝██╔════╝██╔══██╗██╔════╝██║  ██║██╔════╝██║     ██║"
	echo -e "${blueColor} ██║  ██╗    ██║   █████╗  ██║  ██║╚█████╗ ███████║█████╗  ██║     ██║"
	echo -e "${blueColor} ██║  ╚██╗   ██║   ██╔══╝  ██║  ██║ ╚═══██╗██╔══██║██╔══╝  ██║     ██║"
	echo -e "${blueColor} ╚██████╔╝   ██║   ██║     ╚█████╔╝██████╔╝██║  ██║███████╗███████╗███████╗"
	echo -e "${blueColor}  ╚═════╝    ╚═╝   ╚═╝      ╚════╝ ╚═════╝ ╚═╝  ╚═╝╚══════╝╚══════╝╚══════╝${endColor}"
	
	echo -e "\n${redColor}[!] Use: ./gtfoshell${endColor}"
	echo -e "\n\n\t${grayColor}[-b]${endColor}${greenColor} Show the binary information.${endColor}"
	echo -e "\t\t${turquoiseColor} Example: gtfoshell -b chown ${endColor}"
	echo -e "\n\t${grayColor}[-f]${endColor}${greenColor} Specify the function of the binary.${endColor}"
	echo -e "\t\t${turquoiseColor} Example: gtfoshell -b bash -f suid ${endColor}"
	echo -e "\n\t${grayColor}[-a]${endColor}${greenColor} Listing Mode. (default: List all binaries)${endColor}"
	echo -e "\t\t${yellowColor} binaries${endColor}${greenColor}:\tList all binaries${endColor}"
	echo -e "\t\t${yellowColor} functions${endColor}${greenColor}:\tList all functions${endColor}"
	echo -e "\t\t${turquoiseColor} Example: gtfoshell -a ${endColor}"
	echo -e "\t\t\t${turquoiseColor}  gtfoshell -a binaries${endColor}"
	echo -e "\t\t\t${turquoiseColor}  gtfoshell -a functions${endColor}"
	echo -e "\n\t${grayColor}[-h]${endColor}${greenColor} Show this panel${endColor}"

	tput cnorm; exit 1
}

# Create a table
# Credits: https://github.com/gdbtek/linux-cookbooks/blob/master/libraries/util.bash
#  ----------- . -----------
function isEmptyString(){
    local -r string="${1}"

    if [[ "$(trimString "${string}")" = '' ]]
    then
        echo 'true' && return 0
    fi

    echo 'false' && return 1
}

function printTable(){
    local -r delimiter="${1}"
    local -r tableData="$(removeEmptyLines "${2}")"
    local -r colorHeader="${3}"
    local -r displayTotalCount="${4}"

    if [[ "${delimiter}" != '' && "$(isEmptyString "${tableData}")" = 'false' ]]
    then
        local -r numberOfLines="$(trimString "$(wc -l <<< "${tableData}")")"

        if [[ "${numberOfLines}" -gt '0' ]]
        then
            local table=''
            local i=1

            for ((i = 1; i <= "${numberOfLines}"; i = i + 1))
            do
                local line=''
                line="$(sed "${i}q;d" <<< "${tableData}")"

                local numberOfColumns=0
                numberOfColumns="$(awk -F "${delimiter}" '{print NF}' <<< "${line}")"

                # Add Line Delimiter

                if [[ "${i}" -eq '1' ]]
                then
                    table="${table}$(printf '%s#+' "$(repeatString '#+' "${numberOfColumns}")")"
                fi

                # Add Header Or Body

                table="${table}\n"

                local j=1

                for ((j = 1; j <= "${numberOfColumns}"; j = j + 1))
                do
                    table="${table}$(printf '#|  %s' "$(cut -d "${delimiter}" -f "${j}" <<< "${line}")")"
                done

                table="${table}#|\n"

                # Add Line Delimiter

                if [[ "${i}" -eq '1' ]] || [[ "${numberOfLines}" -gt '1' && "${i}" -eq "${numberOfLines}" ]]
                then
                    table="${table}$(printf '%s#+' "$(repeatString '#+' "${numberOfColumns}")")"
                fi
            done

            if [[ "$(isEmptyString "${table}")" = 'false' ]]
            then
                local output=''
                #output="$(echo -e "${table}" | column -s '#' -t | awk '/^\+/{gsub(" ", "-", $0)}1')"
		output="$(echo -e "${table}" | column -s '#' -t | awk '/+/{gsub(" ", "-", $0)}1' | sed 's/^--\|^ //g')"
                if [[ "${colorHeader}" = 'true' ]]
                then
                    echo -e "\033[1;32m$(head -n 3 <<< "${output}")\033[0m"
                    tail -n +4 <<< "${output}"
                else
                    echo "${output}"
                fi
            fi
        fi

        if [[ "${displayTotalCount}" = 'true' && "${numberOfLines}" -ge '0' ]]
        then
            echo -e "\n\033[1;36mTOTAL ROWS : $((numberOfLines - 1))\033[0m"
        fi
    fi
}

function removeEmptyLines(){
    local -r content="${1}"

    echo -e "${content}" | sed '/^\s*$/d'
}

function repeatString(){
    local -r string="${1}"
    local -r numberToRepeat="${2}"

    if [[ "${string}" != '' && "$(isPositiveInteger "${numberToRepeat}")" = 'true' ]]
    then
        local -r result="$(printf "%${numberToRepeat}s")"
        echo -e "${result// /${string}}"
    fi
}
function trimString(){
    local -r string="${1}"

    sed 's,^[[:blank:]]*,,' <<< "${string}" | sed 's,[[:blank:]]*$,,'
}
function isPositiveInteger(){
    local -r string="${1}"
    if [[ "${string}" =~ ^[1-9][0-9]*$ ]]
    then
        echo 'true' && return 0
    fi
    echo 'false' && return 1
}

#  ----------- . -----------


# Global Variables

url="https://gtfobins.github.io/"
url_functions="https://raw.githubusercontent.com/GTFOBins/GTFOBins.github.io/master/_data/functions.yml"
url_info_binary="https://raw.githubusercontent.com/GTFOBins/GTFOBins.github.io/master/_gtfobins/"

function getbinary(){
 
	echo " " > bins.tmp
	while [ "$(cat bins.tmp | wc -l)" == "1" ]; do
		curl -s "$url_info_binary$1.md" > bins.tmp
	done
	
	output=$(cat bins.tmp | grep -vE "\-\-\-|functions:" | sed -e "s/- code/code/g" -e "s/code: |/code:/g" -e "s/description: |/Description:/g" -e "s/- description/Description/g" -e "s/- Description/Description/")
	counter=0
	while IFS= read -r line; do
	
		if [[ $line == *"Description:"* ]]; then
			echo -en "${turquoiseColor}\n\t"
			echo $line
			echo -en "${endColor}"
			counter=1
		else
			if [[ $line == *"code:"* ]]; then
				if [ "$counter" -eq 1 ]; then
					echo -en "\t"
				else
					echo -en "\n\t"
				fi
				counter=0
				echo $line | sed "s/code:/Code:/"
			else
				if [[ $(echo "$line" | grep "^\ .*:$") && $(echo "$line"| wc -w) -eq 1 ]];then	

					line=$(echo $line | tr ":" " "  )
					echo -e "\n${greenColor} Function: ${endColor}$line" 
					
				else
					echo "   $line"
				fi
			fi
		fi
	done < <(printf '%s\n' "$output")     

	tput cnorm
	rm bins.tmp	
} 

function getListBins(){

	list=$(curl -s "$url" | grep 'bin-name' | grep -o -P '(?<=\>).*?(?=\<)')
	echo "$list"
}

function showAllBins(){
	
	echo "BINARIES,BINARIES,BINARIES,BINARIES,BINARIES,BINARIES" > bins.tmp
	while [ "$(cat bins.tmp | wc -l)" == "1" ]; do
		curl -s "$url" | grep 'bin-name' | grep -o -P '(?<=\>).*?(?=\<)' | sed "s/$/,/" | sed -e "0~6 s/,/ /" | tr -d '\n'| tr ' ' '\n' >> bins.tmp
	done
	
	echo -en "${greenColor}" 
	printTable ',' "$(cat bins.tmp)"
	echo -e "${endColor}$line"
	
	rm bins.tmp	
	tput cnorm
}

function getFunctions(){
	output=$(curl -s $url_functions | grep -vE "\-\-\-|#" | sed -e "s/description: |/Description:/g" -e "s/label:/Label:/" -e $"s/description:/Description:/")
	while IFS= read -r line; do
	
		if [[ "$line" == *"Description:"* ]]; then
			line=$(echo "$line" | sed "s/Description://")
			echo -en "${turquoiseColor}  Description:${endColor}\n"
			echo " $line"
		elif [[ $line == *"Label:"* ]]; then
			echo -e "${purpleColor}"
			echo "$line"
			echo -en "${endColor}"
		else
			if [[ $( echo "$line" | grep "^[a-z].*:$" ) ]];then	
				echo -e "\n${greenColor}$line${endColor}" 
			else
				echo "$line"
			fi
		fi
	done < <(printf '%s\n' "$output")     

	tput cnorm
}

function getBinFunc(){
	echo " " > bins.tmp
	while [ "$(cat bins.tmp | wc -l)" == "1" ]; do
		curl -s "$url_info_binary$1.md" > bins.tmp
	done
	listFunc=$(curl -s $url_functions |  grep -o "^[a-z].*:$" | tr ":" " ")
	search=$(echo "$2" | tr '[A-Z]' '[a-z]')
	if [[ ! $listFunc =~ "$search" ]]; then
		echo -e "\n${redColor}[!] This function not found on GTFOBins.\n${endColor}"
		rm bins.tmp; tput cnorm; exit 1
	fi

	aux=0
	counter=0
	output=$(cat bins.tmp | grep -vE "\-\-\-|functions:" | sed -e "s/- code/code/g" -e "s/code: |/code:/g" -e "s/description: |/Description:/g" -e "s/- description/Description/g" -e "s/- Description/Description/")
	
	while IFiS= read -r line; do
		if [[ $(echo "$line" | grep -o "$search") && $aux -eq 0 && $(echo "$line"| wc -w) -eq 1 ]];then	
			line=$(echo $line | tr ":" " ")
			echo -e "\n${greenColor} Function: ${endColor}$line" 
			aux=1
			continue	
		fi
		if [[ $aux -eq 1 ]]; then
			if [[ $line == *"Description:"* ]]; then
				echo -en "${turquoiseColor}\n\t"
				echo $line
				echo -en "${endColor}"
				counter=1
			elif [[ $line == *"code:"* ]]; then
				if [ "$counter" -eq 1 ]; then
					echo -en "\t"
				else
					echo -en "\n\t"
				fi
				echo $line | sed "s/code:/Code:/"
				counter=0
			elif [[ $( echo "$line" | grep "^[a-z].*:$" ) ]];then	
				rm bins.tmp; tput cnorm
				exit 0 
			else
				echo -en "\t    "
				echo "$line"
			fi
		fi
	done < <(printf '%s\n' "$output")     
	rm bins.tmp
	tput cnorm
}

counter=0
while getopts ":b:f:ha" arg; do
	case $arg in
		b) binary=$OPTARG; let counter+=1;;
		f) specify_function=$OPTARG; let counter+=1;;
		a) search_all=$OPTARG;
    			eval nextopt=\${$OPTIND}
    			if [[ -n $nextopt && $nextopt != -* ]] ; then
		  		OPTIND=$((OPTIND + 1))
      				search_all=$nextopt
    			else
      				search_all=1
    			fi
    			let counter+=1;;
		h) HelpPanel;;
	esac
done

tput civis

if [[ "$binary" && "$search_all" || "$counter" -eq 0 || "$counter" -eq 3 ]] ; then

	HelpPanel
else
	
	if [ "$binary" ]; then
		allBins="$(getListBins)"
		if [[ $allBins =~ "$binary" ]]; then
			if [ "$specify_function" ]; then
				getBinFunc "$binary" "$specify_function"
			else 
				getbinary "$binary"
			fi
		
		else
			echo -e "\n${redColor}[!] This binary not found on GTFOBins.\n${endColor}"
			tput cnorm
			exit 1
		fi

	elif [[ "$search_all" == "binaries" || "$search_all" -eq 1 ]]; then
		showAllBins
	elif [ "$search_all" == "functions" ]; then
		getFunctions
	else
		HelpPanel
	fi
	
fi