OTUS Linux HW6 lsof.sh v2 (works on CentOS 7.4)

lsof.sh

#!/bin/bash
getstate() 
{
	case $1 in
	  '01') st='ESTABLISHED';;
      '02') st='SYN_SENT';;
      '03') st='SYN_RECV';;
      '04') st='FIN_WAIT1';;
      '05') st='FIN_WAIT2';;
	  '06') st='TIME_WAIT';;
      '07') st='CLOSE';;
      '08') st='CLOSE_WAIT';;
      '09') st='LAST_ACK';;
      '0A') st='LISTEN';;
      '0B') st='CLOSING';;
      *) st='UNKNOWN';;	
	esac
	echo $st
}

ipv4()
{
    echo "$((16#${1:6:2})).$((16#${1:4:2})).$((16#${1:2:2})).$((16#${1:0:2}))"
}

ipv6()
{

	#0000 0000 0000 0000 0000
    echo "${1:12:4}:${1:8:4}:${1:4:4}:${1:0:4}"
}

portv4()
{
    echo "$((16#$1))"
}

ipv4tcp(){
	
	echo "TCP: "$(ipv4 $2)":"$(portv4 $( echo $2 | cut -d ":" -f 2))" -> "$(ipv4 $3)":"$(portv4 $( echo $3 | cut -d ":" -f 2)) "[$(getstate $4)]"

}

ipv4udp(){
	
	echo "UDP: "$(ipv4 $2)":"$(portv4 $( echo $2 | cut -d ":" -f 2))

}

ipv6tcp(){
	
	echo "TCP6: "$(ipv6 $2)":"$(portv4 $( echo $2 | cut -d ":" -f 2))" -> "$(ipv6 $3)":"$(portv4 $( echo $3 | cut -d ":" -f 2)) "[$(getstate $4)]"

}

ipv6udp(){
	
	echo "UDP6: "$(ipv6 $6)":"$(portv4 $( echo $2 | cut -d ":" -f 2))

}


procfiles(){

p_pid=$1

exec 2>/dev/null

procpath="/proc/"$p_pid
if ! [ ! -d procpath ]; then continue; fi
p_comm=$(cat $procpath"/comm" | cut -c -9)
#p_cwd=$(cat $1"/cwd")
for f in $( ls $procpath"/fd" | grep -E '^[0-9]+$' | sort -n);  do
    	#echo $(stat -L $procpath"/fd/"$f --format "%i %d (%F) (%U) %t %T %s")
    	regex='([0-9]*) ([a-dA-F0-9]*) \((.*)\) \((.*)\).* ([a-dA-F0-9]*) ([a-dA-F0-9]*) ([0-9]*)'

    	if [[ $(stat -L $procpath"/fd/"$f --format "%i %d (%F) (%U) %t %T %s") =~ $regex ]]; then

			
			#			echo "$(stat -L $procpath"/fd/"$f --format "%i %d (%F) (%U) %t %T %s") "
			p_size=${BASH_REMATCH[7]}
			p_user=$(stat $procpath"/fd/"$f --format "%U")
			p_device=${BASH_REMATCH[2]}
			p_inode=${BASH_REMATCH[1]}
			# echo "0x"${BASH_REMATCH[5]} "0x"${BASH_REMATCH[6]}
			if [ ${BASH_REMATCH[5]} -gt 0 ] || [ ${BASH_REMATCH[6]} -gt 0 ]; then
				major="0x"${BASH_REMATCH[5]}
				minor="0x"${BASH_REMATCH[6]}
			else
				major="0x"$((${BASH_REMATCH[2]} >> 8))
				minor="0x"$((${BASH_REMATCH[2]} & 0xFF))
			fi




			p_path=$( readlink -n $procpath"/fd/"$f)
    		case ${BASH_REMATCH[3]} in
    			"regular file") 
					p_type="REG"
					;;
				"regular empty file")
					p_type="REG"
					;;
				"character special file") 
					p_type="CHR"
					;;
				"directory") 
					p_type="DIR"
					;;
						
				"fifo") 
					p_type="FIFO"
					p_path=$( readlink -n $procpath"/fd/"$f)		
					;;
				"socket") 
					p_type=$(grep -e " "$p_inode" " /proc/net/* 2>/dev/null | cut -d ":" -f 1 | cut -d "/" -f 4)
					if [ ! -z $p_type ]; then
						case $p_type in
							"tcp")
								p_type="IPv4"
								p_path=$(ipv4tcp $(grep -h -e " "$p_inode" " /proc/net/* 2>/dev/null))
							;;
							"udp")
								p_type="IPv4"
								p_path=$(ipv4udp $(grep -h -e " "$p_inode" " /proc/net/* 2>/dev/null))
							;;
							"tcp6")
								p_type="IPv6"
								p_path=$(ipv6tcp $(grep -h -e " "$p_inode" " /proc/net/* 2>/dev/null))
							;;
							"udp6")
								p_type="IPv6"
								p_path=$(ipv6tcp $(grep -h -e " "$p_inode" " /proc/net/* 2>/dev/null))
							;;

							*)
								p_path=$( readlink -n $procpath"/fd/"$f)
							;;		
						esac
					else 
						p_type="socket"
						p_path=$( readlink -n $procpath"/fd/"$f)		
					fi

					
					;;
				"weird file") 
					p_type="a_inode"
					p_path=$( readlink -n $procpath"/fd/"$f | cut -d ":" -f 2 )		
					;;
				*) 
					p_type="?"
					p_path=$( readlink -n $procpath"/fd/"$f)		
					;;
			esac
			#echo $(grep ${BASH_REMATCH[1]} /proc/net/* 2>/dev/null)
			#echo "=-==="

			
	  		printf "%-9s %4s %8s %4s %9s %2d,%2d %16s %16s %s\n" "$p_comm" $p_pid $p_user $f "$p_type" "$major" "$minor" $p_size $p_inode "$p_path" #| cut -c-$(tput cols)
    	fi
done
}


#MAIN
LANG=en_US.UTF8
printf "%-9s %4s %8s %4s %9s %4s %16s %15s %s\n" "COMMAND" "PID" "USER" "FD" "TYPE"  "DEVICE" "SIZE" "NODE" "NAME"

if [ $# -eq 0 ]; then
for i in $(ls /proc/ | grep -E '^[0-9]+$' | sort -n); do
	#echo $i
	procfiles "$i"
done
fi


while getopts ":p:" opt; do
	case $opt in
		(p) procfiles "$OPTARG" ;;
	esac
done