Memorable but secure passwords
Command Line – Password Generators
CLI tools for generating passwords have many options that can help you strike a balance between ease of use and security.
How should you generate passwords? You probably know the standard advice of using a variety of characters, but the resulting passwords are hard to remember, especially since the recommended length keeps getting longer as cracking methods become more sophisticated. It's enough to make users choose convenience over security and use the same password everywhere – which is just about the worst thing you can do. Yet even if you choose unique passwords in every circumstance, how random can passwords invented by one person truly be? And what strategies can you use to make random passwords memorable? A password manager can ease the daily burden, but what happens if your password manager becomes corrupted? What were simple issues a couple of decades ago have become complicated today, with no easy answers.
Ask security experts, and the answers to these questions can be conflicting. However, that doesn't stop the developers of password generators illustrating possible solutions. Many implement traditional answers, but others are starting to implement ways of making passwords more memorable, either by tweaking tradition in various ways or taking a new approach altogether.
PWGen
PWGen is one of the oldest password generators for Linux [1]. It is based on the traditional password advice, providing eight character strings for passwords that include lower- and uppercase letters, numerals, and special characters. This pattern can be modified by the options in Table 1 to produce an easier to remember password, but remember that excluding types of characters will probably result in a weaker password. For maximum security, specify --secure
(-s
), which will maximize the mixture of characters (Figure 1).
Table 1
PWGen Customization Options
--no-numerals (-0) |
Exclude numbers |
--no-capitalize (-A) |
Exclude uppercase letters |
--ambiguous (-B) |
Exclude confusing characters, like upper case O and zero (0). |
--capitalize (-c) |
Include at least one capital |
--numerals (-n) |
Include at least one number |
--no-vowels (-v) |
Exclude vowels and numbers that could be mistaken for vowels like 1 or 0 |
--symbols (-y) |
Include at least one special character |
Results are displayed in columns by default. However, you can use --lines
(-l
) to display results one per line. You can also control the number of results with --num-passwords=NUMBER
(-N
).
PWGen provides a wealth of options, but notice that its passwords are eight characters long. That used to be an adequate length and still provides moderate security. However, using traditional password standards, an increasing number of experts suggest a minimum of 12 characters. If the password you are generating is important to you, you might want to use another password generator.
pwmake
pwmake
is a simple utility available in the libpwquality-tools package [2]. It includes only one option: the amount of entropy bits used to generate the password (Figure 2). The minimum number of bits is 56. The man page suggests 64 bits when attackers do not have direct access to the password hash file, or 80-128 bits when attackers might have access or the password is used as an encryption key. However the number of bits can go even higher, if desired. The entropy is generated by /dev/urandom
. After generating the password, you can use pwscore
or pam_pwquality
, two other utilities in libpwquality-tools, to check the strength of the generated password. Since the passwords are random and long, you will probably only want to use pwmake
with a password manager.
gpw
gpw
[3] is another simple password generator. It uses two options: the number of passwords generated, and the length of each password. Unlike pwmake
, gpw
generates passwords that are easy to pronounce for English speakers and should therefore be easy to remember. The price for easier to remember passwords, of course, is less security (Figure 3).
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
New Steam Client Ups the Ante for Linux
The latest release from Steam has some pretty cool tricks up its sleeve.
-
Gnome OS Transitioning Toward a General-Purpose Distro
If you're looking for the perfectly vanilla take on the Gnome desktop, Gnome OS might be for you.
-
Fedora 41 Released with New Features
If you're a Fedora fan or just looking for a Linux distribution to help you migrate from Windows, Fedora 41 might be just the ticket.
-
AlmaLinux OS Kitten 10 Gives Power Users a Sneak Preview
If you're looking to kick the tires of AlmaLinux's upstream version, the developers have a purrfect solution.
-
Gnome 47.1 Released with a Few Fixes
The latest release of the Gnome desktop is all about fixing a few nagging issues and not about bringing new features into the mix.
-
System76 Unveils an Ampere-Powered Thelio Desktop
If you're looking for a new desktop system for developing autonomous driving and software-defined vehicle solutions. System76 has you covered.
-
VirtualBox 7.1.4 Includes Initial Support for Linux kernel 6.12
The latest version of VirtualBox has arrived and it not only adds initial support for kernel 6.12 but another feature that will make using the virtual machine tool much easier.
-
New Slimbook EVO with Raw AMD Ryzen Power
If you're looking for serious power in a 14" ultrabook that is powered by Linux, Slimbook has just the thing for you.
-
The Gnome Foundation Struggling to Stay Afloat
The foundation behind the Gnome desktop environment is having to go through some serious belt-tightening due to continued financial problems.
-
Thousands of Linux Servers Infected with Stealth Malware Since 2021
Perfctl is capable of remaining undetected, which makes it dangerous and hard to mitigate.