Command-line utility to manage passwords, protected by sudo

userpass.sh

#!/bin/bash

file=/home/$SUDO_USER/.local/share/userpass.list

function showHelp {
version=0.0.2
versionDate="2014-06-24"
echo "$0 - manage passwords


Mainted at: https://gist.github.com/swarminglogic/??
Author:     Roald Fernandez (github@swarminglogic.com)
Version:    $version ($versionDate)
License:    CC-zero (public domain)
"
    exit $1
}

function echoerr {
    echo -e "$@" 1>&2;
}

tmp=$@
while test $# -gt 0; do
    case "$1" in
        -h|--help)
            showHelp 0
            ;;
        -a)
            shift
            isAdd=yes
            add=$1
            shift
            ;;
        --add=)
            isAdd=yes
            add=`echo $1 | sed -e 's/^[^=]*=//g'`
            shift
            ;;
        -u)
            shift
            isUser=yes
            username=$1
            shift
            ;;
        --username=*)
            isUser=yes
            username=`echo $1 | sed -e 's/^[^=]*=//g'`
            shift
            ;;
        -m)
            shift
            isMeta=yes
            meta="$1"
            shift
            ;;
        --meta=*)
            isMeta=yes
            meta=`echo $1 | sed -e 's/^[^=]*=//g'`
            shift
            ;;
        -p)
            shift
            isPass=yes
            pass=$1
            shift
            ;;
        --password=*)
            isPass=yes
            pass=`echo $1 | sed -e 's/^[^=]*=//g'`
            shift
            ;;
        --script)
            shift
            isScript=yes
            ;;
        *)
            shift
            ;;
    esac
done

function configureFile {
    if [ ! -d "`dirname $file`" ] ; then
        mkdir -p "`dirname $file`"
    fi
    if [ ! -e "$file" ] ; then
        touch "$file"
        chmod -r "$file"
    fi
}


function lcsubstr {
    word1="${1,,}"
    word2="${2,,}"
    if [ ${#word1} -lt ${#word2} ]
    then
        word1="$2"
        word2="$1"
    fi
    for ((i=${#word2}; i>0; i--)); do
        for ((j=0; j<=${#word2}-i; j++)); do
            if [[ $word1 =~ ${word2:j:i} ]]
            then
                echo ${word2:j:i}
                exit
            fi
        done
    done
}

# $1: userpass entry  $2:column (1:key, 2:username, 3:pass, 4:meta)
function extractColumn {
    echo $1 | cut -d":" -f${2} | sed -e 's/^ *//' -e 's/ *$//'
}

function queryExactEntry {
    line=$(grep "^[^:]*${1}.*:"  $file)
    if [[ $line ]] ; then
        key=$(extractColumn "$line" 1)
        username=$(extractColumn "$line" 2)
        pass=$(extractColumn "$line" 3)
        meta=$(extractColumn "$line" 4)
        echo "key:      $key"
        echo "username: $username"
        echo "password: $pass"
        echo "meta:     $meta"
    fi
}

if [[ $EUID -ne 0 ]] ; then
   echo "This script must be run as root" 1>&2
   showHelp 1
fi

configureFile

if [[ $isAdd ]] ; then
    if [[ $isUser ]] && [[ $isPass ]] && [[ $isMeta ]] ; then
        if [[ $add ]] && [[ $username ]] && [[ $pass ]] && [[ $meta ]] ; then
            echo "${add} : ${username} : ${pass} : ${meta}" >> $file
        else
            echo "Missing paramater information";
            exit 1
        fi
    else
        showHelp 1
    fi
else
    set -- $tmp
    if [[ $isScript ]] ; then
        if [[ $meta ]] ; then
            mfile=""
            cfile=""
            while read l; do
                entry=`echo $l | cut -d":" -f4 | sed -e 's/^ *//' -e 's/ *$//'`
                lcss=`lcsubstr "${entry,,}" "${meta,,}"`
                if [[ ${#lcss} -ge ${#entry} ]] ; then
                    mfile+="${#lcss}  $l"$'\n'
                fi
            done <$file

            echo "$mfile" | sort -n | cut -d" " -f2- | tail -n1 | \
                 cut -d":" -f1 | sed -e 's/^ *//' -e 's/ *$//'

        else
            line=`grep "^$2 " $file`
            if [[ $isUser ]] ; then
                extractColumn "$line" 2
            elif [[ $isPass ]] ; then
                extractColumn "$line" 3
            elif [[ $isMeta ]] ; then
                extractColumn "$line" 4
            else
                echo $line
            fi
        fi
    else
        queryExactEntry $1
    fi
fi

What do you think about encrypting the file with passwords rather than rely on root to protect it? It should be very similar for the user, because ssh-agent would ask the master password to the key and remember it for the session (if it's configured to do so).