demo_encrypt_decrypt.sh

#!/bin/sh

keylength=8
algo=$1
[[ "$algo" = "aes" ]] && keylength=16
[[ "$algo" = "3des" ]] && keylength=24

encfile=$(mktemp -t _encXXXXXX) && \
    keyfile=$(mktemp -t _encXXXXXX) && \
    dd if=/dev/urandom of="$keyfile" bs="$keylength" count=1 >/dev/null 2>&1 && \
    encrypt -a "$algo" -k "$keyfile" -i /etc/resolv.conf -o "$encfile" && \
    decrypt -a "$algo" -k "$keyfile" -i "$encfile"
rc=$?

rm "$encfile" "$keyfile"
exit $rc