A script that can help you encrypt strings in the shell.

enc-helper.sh

#!/bin/bash

set -o errexit
set -o pipefail
set -o nounset

OPENSSL=${OPENSSL:-$(which openssl)}

help() {
    printf "$0 -h\n\tShow help.\n"
    printf "$0 -t\n\tDo not show how to decrypt.\n"
    printf "$0 -i INPUT\n\tInput.\n"
    printf "$0 -k KEY\n\tKey.\n"
    printf "$0 -c CIPHER\n\tCipher. Default \"aes-256-cbc\". See \"openssl enc -list\".\n"
    printf "$0 -d DIGEST\n\tDigest. Default \"sha256\". See \"openssl dgst -list\".\n"
}

check_openssl() {
    if [[ $(${OPENSSL} version) != LibreSSL\ 2.* ]]; then
        return
    fi
    echo "The \"$($OPENSSL version)\" no support, please update LibreSSL to 3.x or use OpenSSL."
    echo "You can specify the OpenSSL bin path through the environment variable \"OPENSSL\", for example:"
    printf "\n\tOPENSSL=/usr/local/opt/openssl@1.1/bin/openssl $0\n\n"
    exit 1
}

main() {
    check_openssl
    while getopts "hi:k:c:d:t" OPT; do
        case ${OPT} in
        h) help && exit 0 ;;
        t) _ht=0 ;;
        i) _input="${OPTARG}" ;;
        k) _key="${OPTARG}" ;;
        c) _cipher="${OPTARG}" ;;
        d) _digest="${OPTARG}" ;;
        ?) help && exit 1 ;;
        esac
    done

    _cipher=${_cipher:-"aes-256-cbc"}
    _digest=${_digest:-"sha256"}

    if [[ ${_input:-} == "" ]]; then
        printf "input is empty\n\n"
        help
        exit 1
    fi

    if [[ ${_key:-} == "" ]]; then
        printf "key is empty\n\n"
        help
        exit 1
    fi

    _enc=$(printf "%s" "${_input}" | $OPENSSL enc -${_cipher} -pbkdf2 -k ${_key} -a -A)
    _checksum=$(printf "%s" "${_input}" | openssl dgst -${_digest} -hmac ${_key} | awk '{print $2}')

    printf "%30s: ${_input}\n%30s: ${_key}\n%30s: ${_enc}\n%30s: ${_checksum}\n" "Input" "Key" "Ciphertext(${_cipher})" "HMAC(${_digest})"

    if [[ ${_ht:-1} == 1 ]]; then
        printf "How to decrypt:\n\techo -n \"${_enc}\" | openssl ${_cipher} -pbkdf2 -k \"${_key}\" -a -A -d\n"
        printf "How to verify:\n\ttest \"${_checksum}\" = \$(echo -n \"${_enc}\" | openssl ${_cipher} -pbkdf2 -k \"${_key}\" -a -A -d | openssl ${_digest} -hmac \"${_key}\" | awk '{print \$2}')\n"
    fi
}

main "$@"

Example:

$ bash <(curl -s https://gist.githubusercontent.com/hr3lxphr6j/f00934e796a3c57beb2145209eae5c5c/raw) -i "AccessKeyID" -k "Password"
                         Input: AccessKeyID
                           Key: Password
       Ciphertext(aes-256-cbc): U2FsdGVkX18GVGq6fNdZvnUieCa2TSi58RIqetgTq+4=
                  HMAC(sha256): ee5395b909d9b5a57b8344c20f687b6c0e881db4a7fcc90f0f3a7375d6d0966c
How to decrypt:
	echo -n "U2FsdGVkX18GVGq6fNdZvnUieCa2TSi58RIqetgTq+4=" | openssl aes-256-cbc -pbkdf2 -k "Password" -a -A -d
How to verify:
	test "ee5395b909d9b5a57b8344c20f687b6c0e881db4a7fcc90f0f3a7375d6d0966c" = $(echo -n "U2FsdGVkX18GVGq6fNdZvnUieCa2TSi58RIqetgTq+4=" | openssl aes-256-cbc -pbkdf2 -k "Password" -a -A -d | openssl sha256 -hmac "Password" | awk '{print $2}')