Safe rm

safe-rm.sh

#!/bin/bash
# Laytan Laats - 1012512 - INFD 20-1

# Check if file is being sourced, which will need to add the alias
if [[ "${BASH_SOURCE[0]}" != "${0}" ]]
then
    echo "Adding safe delete alias."
    alias rm="$(pwd)/1012512.sh"
    return
fi

# Need at least one argument
if [[ $# -lt 1 ]]
then
    echo "Please enter the file to be deleted."
    exit
fi

# Parse arguments: https://stackoverflow.com/questions/192249/how-do-i-parse-command-line-arguments-in-bash
POSITIONAL=()
while [[ $# -gt 0 ]]
do
    key="$1"

    case $key in
        -u)
        UNDELETE=YES
        shift
        ;;
        -r)
        RECURSIVE=YES
        shift
        ;;
        -p)
        PASSWORD="$2"
        shift
        shift
        ;;
        *)    # unknown option
        POSITIONAL+=("$1") # save it in an array for later
        shift # pass argument
        ;;
    esac
done
set -- "${POSITIONAL[@]}" # restore positional parameters
TARGET="$1"

REGISTER="$HOME/trash/register"
ZIPPED="$HOME/trash/zipped"

# check if ~/trash does not exist
if [ ! -d $HOME/trash ]
then
    # create it
    mkdir $HOME/trash
    # create zipped folder
    mkdir $HOME/trash/zipped
    # create trash register file
    touch $HOME/trash/register
fi

# if -u
if [ "$UNDELETE" == "YES" ]
then
    # find the target in the register
    lineNumber=0
    while IFS= read -r line
    do
        lineNumber=$((lineNumber+1))
        seperated=($line) # turn string into array seperated by spaces
        if [ "${seperated[0]}" == "$TARGET" ]
        then
            found=YES
            hash="${seperated[1]}"
            break
        fi
    done < "$REGISTER"

    if [ "$found" != "YES" ]
    then
        echo "File not found in trash"
        exit
    fi

    # if password protected
    if [ $hash ]
    then
        # ask for password 3 times
        for i in {1..3}
        do
            echo "Please enter the password for this file/directory:"
            read password
            # verify password hash
            hashedInput=$(openssl passwd -salt "$TARGET" "$password")
            if [ "$hash" != "$hashedInput" ]
            then
                echo "Try again"
            else
                echo "Password correct"
                correct="YES"
                break
            fi
        done

        # Make sure password has been correctly filled in
        if [ "$correct" != "YES" ]
        then
            echo "Password incorrect"
            exit
        fi
    fi
    # unzip the file
    unzip "$ZIPPED/$TARGET.zip"
    # remove zip file
    rm "$ZIPPED/$TARGET.zip"
    # remove lines starting with target from ~/trash/register
    sed -i "/^${TARGET}/d" "$REGISTER"
    # done
    echo "File undeleted"
else
    # confirm delete
    echo "Type \"yes\" to delete $TARGET"
    read confirm
    if [ "$confirm" != "yes" ]
    then
        echo "Not deleting"
        exit
    fi
    # check argument is a directory
    if [ -d $TARGET ]
    then
        echo "Target is a directory"
        # check -r argument passed, error if not
        if [ "$RECURSIVE" != "YES" ]
        then
            echo "Not deleting a directory without -r passed"
            exit
        fi
    fi
    # check -p is given
    if [ $PASSWORD ]
    then
        # hash password
        hashedPassword=$(openssl passwd -salt "$TARGET" "$PASSWORD")
    fi
    # enter line into ~/trash/register
    echo "$TARGET $hashedPassword" >> "$REGISTER"
    # zip file/directory
    zip -r "${TARGET}.zip" "$TARGET"
    # move to ~/trash/zipped
    mv "${TARGET}.zip" "$ZIPPED/${TARGET}.zip"
    # remove original file/directory
    rm -rf "$TARGET"
    echo "File/Directory deleted"
fi