How to Generate, Encrypt, and Decrypt Random Passwords on Linux with pwgen and OpenSSL

Generate Random Passwords

Use pwgen to produce random strings containing uppercase, lowercase letters and digits. The following command creates 20 passwords, each 10 characters long: $ pwgen -1 -s 10 20 The output consists of one password per line, for example:

Rav0iusaPh
yoo1IeNo6G
oh d0oiThao
eit8Aeje8V
Chah5naoXa
oob0coh2Ph
Phei7oong2
EiQuai2shu
iM6ahne2ju
Ohd9ahteez
Qua4ruFohc
Jeeva5dofa
Ush5phohqu
ieNgieJo0m
Pheiphye8S
yohxie0Doh
Zei7ooThie
mohd4Aethi
kae9aiXaiP
eiZ3seeHah

Encrypt Passwords

First generate an RSA private key with OpenSSL:

$ openssl genpkey -algorithm RSA -out private.key

This creates private.key, which can be used for encryption and decryption. To encrypt a file password.txt containing the passwords, run:

$ openssl pkeyutl -in password.txt -out password.enc -encrypt -inkey private.key

The result is the encrypted file password.enc.

Decrypt Passwords

Use the same private key to decrypt:

$ openssl pkeyutl -in password.enc -out password.txt -decrypt -inkey private.key

The decrypted content is written back to password.txt.

Security Considerations

Always choose strong passwords for the generated keys and store the private key in a secure location to maintain confidentiality.