npwg - Secure Password Generator

npwg is a secure password generator written in Rust. With npwg, you can easily generate strong and random passwords or passphrases to protect your online accounts.

Features

• Generate passwords with custom length and count
• Support various defined character sets
• Generate diceware passwords
• Generate pronounceable passwords
• Customizable password length, count, character sets, and separators
• Avoid repeating characters in passwords
• Display statistics about the generated passwords
• Show the estimated strength of the generated passwords
• Interactive mode for easy password generation
• Deterministic mode for password derivation from a master password and service

Installation

Using Cargo

If you have Rust and Cargo installed, you can install npwg using the following command:

cargo install npwg

This will download and compile the latest version of npwg and install it in your Cargo binary directory.

Manual Installation

1. Make sure you have Rust installed on your system. If not, you can download it from the official Rust website: https://www.rust-lang.org/tools/install
2. Clone this repository:

   git clone https://github.com/vschwaberow/npwg.git
   

3. Navigate to the project directory:

   cd npwg
   

4. Build the project:

   cargo build --release
   

5. The executable can be found at target/release/npwg.

Usage

npwg [OPTIONS]

Options

• -l, --length <LENGTH>: Sets the length of the password [default: 16]
• -c, --count <COUNT>: Sets the number of passwords to generate [default: 1]
• --avoid-repeating: Avoid repeating characters in the password
• --stats: Show statistics about the generated passwords
• --strength: Show strength meter for the generated passwords
• -a, --allowed <CHARS>: Sets the allowed characters [default: allprint]
• --use-words: Use words instead of characters
• -i, --interactive: Start interactive console mode
• --separator <SEPARATOR>: Sets the separator for diceware passphrases (single character or 'random')
• --pronounceable: Generate pronounceable passwords
• --mutate: Mutate the passwords
• --mutation-type <TYPE>: Type of mutation to apply [default: replace]
• --mutation-strength <STRENGTH>: Strength of mutation [default: 1]
• --lengthen <INCREASE>: Increase the length of passwords during mutation
• --copy: Copy the generated password to the clipboard
• --qr: Print the generated passwords as QR codes
• --deterministic: Generate passwords deterministically from a master password and service
• -S, --service <SERVICE>: Service or context name used as salt for deterministic generation
• -u, --username <USERNAME>: Optional username for deterministic generation
• --counter <COUNTER>: Counter for deterministic generation [default: 1]
• -h, --help: Print help
• -V, --version: Print version

Predefined Character Sets

• symbol1, symbol2, symbol3: Different sets of symbols
• digit: Numeric digits
• lowerletter: Lowercase letters
• upperletter: Uppercase letters
• shell: Shell-safe characters
• homoglyph1 to homoglyph8: Various homoglyph sets
• slashes, brackets, punctuation: Specific character types
• all, allprint, allprintnoquote, etc.: Various combinations of character types

Example Recipes

Quick Passwords

Generate default credentials:

npwg

Specify length, count, and character sets:

npwg --length 20 --count 3 --allowed upperletter,lowerletter,digit

Inspect entropy and statistics in one pass:

npwg --strength --stats

Copy freshly generated secrets to the clipboard:

npwg --copy

Render passwords as QR codes (one per password):

npwg --qr --count 2

Diceware Passphrases

First run downloads and verifies the EFF wordlist automatically. Generate six-word phrases separated by spaces:

npwg --use-words --length 6

Customise separators or request random punctuation between words:

npwg --use-words --separator "-" --length 5
npwg --use-words --separator random --length 7

Pronounceable and Pattern Modes

Create pronounceable strings that alternate consonants and vowels:

npwg --pronounceable --length 10

Enforce structural patterns (L=letter, D=digit, S=symbol):

npwg --pattern LLDDS --length 16

Mutation Workflow

Tweak existing passwords by applying deterministic mutations and optional lengthening:

npwg --mutate --mutation-type swap --mutation-strength 2 --lengthen 3

Deterministic Mode

Derive a stable password from a master password and service context (no randomness):

npwg --deterministic --service example.com --length 24

Include an optional username and counter to create distinct variants:

npwg --deterministic --service example.com --username alice --counter 2 --length 24

Use interactive mode for guided generation and mutation prompts:

npwg --interactive

Configuration Profiles

Create a config.toml in ~/.config/npwg/ (or ~/.npwg/ on systems without XDG directories) to store defaults and reusable profiles:

[defaults]
length = 20
allowed = "upperletter,lowerletter,digit"

[profiles.work]
count = 5
use_words = true
separator = "-"

Invoke a profile at runtime:

npwg --profile work

Provide a custom config path when needed:

npwg --config ./fixtures/npwg.toml --profile personal

Use built-in policies for common compliance regimes; these enforce minimum length and character-set expectations before applying your overrides:

npwg --policy windows-ad
npwg --policy pci-dss --count 10

Contributing

Contributions are welcome! If you find a bug or have a suggestion for improvement, please open an issue or submit a pull request.

When contributing Rust code, include only the SPDX license header at the top of each *.rs file—avoid additional inline or block comments elsewhere.

License

This project is licensed under the MIT License.