How to use openssl to output encrypted/decrypted message to stdout - bash

Question

I am just trying to encrypt/decrypt a password with the shell (non-interactively - it's for an automated script). I am following this example:
https://superuser.com/a/20552/362669
I tried converting it to this so that it doesn't use a file output.bin to store the encrypted text:
#!/usr/bin/env bash
cd `dirname "$BASH_SOURCE"`
# generate a 2048-bit RSA key and store it in key.txt
openssl genrsa -out key.txt 2048
# encrypt "hello world" using the RSA key in key.txt
encrypted="$(echo "hello world" | openssl rsautl -inkey key.txt -encrypt)"
echo "encrypted: $encrypted"
# decrypt the message and output to stdout
decrypted="$(echo "$encrypted" | openssl rsautl -inkey key.txt -decrypt)"
echo "decrypted: $decrypted";
but all I get is this garbully-guk:
Generating RSA private key, 2048 bit long modulus
........................................................................................................................+++
............................+++
e is 65537 (0x10001)
��◆J��┌ܥײ��R▒��%⎽F�� 1l�}�%��?�0���+��%���C�8|_/!�A"Ꜵ:�������.��W2Pras��1���� ��(�a
��]�[�남␍◆�=┬─�з≤�ɦ�;�└�1MFP��^␋�#D� �T_⎺F�Eπ�2��U2Ÿ┌π��N│�� ⎽��_\2�� 8V��%��(�^���␍4�#�π���*^D ���/�└�
RSA ⎺⎻␊⎼▒├␋⎺┼ ␊⎼⎼⎺⎼
4662363756:␊⎼⎼⎺⎼:04FFF06B:⎼⎽▒ ⎼⎺┤├␋┼␊⎽:CRYPTO_␋┼├␊⎼┼▒┌:␉┌⎺␌┐ ├≤⎻␊ ␋⎽ ┼⎺├ 02:/B┤␋┌␍R⎺⎺├/L␋␉⎼▒⎼≤/C▒␌␤␊⎽/␌⎺└.▒⎻⎻┌␊.│␉⎽/S⎺┤⎼␌␊⎽/┌␋␉⎼␊⎽⎽┌/┌␋␉⎼␊⎽⎽┌-22.260.1/┌␋␉⎼␊⎽⎽┌-2.6/␌⎼≤⎻├⎺/⎼⎽▒/⎼⎽▒_⎻┐1.␌:185:
4662363756:␊⎼⎼⎺⎼:04FFF072:⎼⎽▒ ⎼⎺┤├␋┼␊⎽:CRYPTO_␋┼├␊⎼┼▒┌:⎻▒␍␍␋┼± ␌␤␊␌┐ °▒␋┌␊␍:/B┤␋┌␍R⎺⎺├/L␋␉⎼▒⎼≤/C▒␌␤␊⎽/␌⎺└.▒⎻⎻┌␊.│␉⎽/S⎺┤⎼␌␊⎽/┌␋␉⎼␊⎽⎽┌/┌␋␉⎼␊⎽⎽┌-22.260.1/┌␋␉⎼␊⎽⎽┌-2.6/␌⎼≤⎻├⎺/⎼⎽▒/⎼⎽▒_␊▒≤.␌:580:
␍␊␌⎼≤⎻├␊␍:
▒┌␊│⎽-└▒␌:␋┼├␊⎼⎺⎽ ▒┌␊│$
and my shell session is basically messed up.
Anyone know what that is? Maybe it's outputting characters that the shell can't handle?
Update: if I don't log the encrypted value, then I get this:
Generating RSA private key, 2048 bit long modulus
........................+++
..........+++
e is 65537 (0x10001)
RSA operation error
4558829164:error:04FFF06B:rsa routines:CRYPTO_internal:block type is not 02:/BuildRoot/Library/Caches/com.apple.xbs/Sources/libressl/libressl-22.260.1/libressl-2.6/crypto/rsa/rsa_pk1.c:185:
4558829164:error:04FFF072:rsa routines:CRYPTO_internal:padding check failed:/BuildRoot/Library/Caches/com.apple.xbs/Sources/libressl/libressl-22.260.1/libressl-2.6/crypto/rsa/rsa_eay.c:580:
decrypted:

Answer 1

I think the best idea would be to convert the binary to/from base64.
Just pipe output through a "openssl base64" to command to enable and "openssl base64 -d" command to decode.
so:
encrypted="$(echo "hello world" | openssl rsautl -inkey key.txt
-encrypt | openssl base64)"
and
decrypted="$(echo "$encrypted" | openssl base64 -d | openssl rsautl
-inkey key.txt -decrypt)"