BIP-39 Mnemonic Generator

This crate provides a function to generate a BIP-39 mnemonic, which is a sequence of words used for securely storing cryptocurrency keys or other sensitive information. The mnemonic is derived from entropy and can be used for purposes like key generation or recovery.

Features

• Generates BIP-39 mnemonics of valid lengths (12, 15, 18, 21, or 24 words).
• Ensures the mnemonic follows the BIP-39 standard, including checksum calculation.
• Can be integrated for wallets for Bitcoin, Ethereum or Solana.

Installation

To use this crate, include it in your Cargo.toml:

[dependencies]
bip39-mnemonic = "0.1"

or use the command :

cargo add bip39_mnemonic_generator

Ensure you add the appropriate version of the crate based on your requirements.

How to Use

1. Add the crate to your project: In your Rust project, include the crate in Cargo.toml as mentioned above.

2. Use the mnemonic generator: The crate exposes a function generate_mnemonic that takes the number of words you want in your mnemonic. The function returns a Result with either a space-separated string of words or an error message if the input length is invalid.

Example Usage

use bip39_mnemonic::generate_mnemonic;

fn main() {
    let mnemonic_result = generate_mnemonic(12); // 12 words mnemonic

    match mnemonic_result {
        Ok(mnemonic) => println!("Generated Mnemonic: {}", mnemonic),
        Err(err) => eprintln!("Error: {}", err),
    }
}

Explanation

• generate_mnemonic(length: usize) -> Result<String, String>:

  • Parameters:
    • length: The desired number of words in the mnemonic. This must be a multiple of 3 (12, 15, 18, 21, or 24).
  • Returns: A Result:
    • Ok(String) containing the mnemonic, if successful.
    • Err(String) containing an error message if the length is invalid.

• Mnemonic Generation Process:

  • Entropy is generated randomly based on the requested length, where the number of bytes is calculated based on the word count.
  • A checksum is derived by hashing the entropy using SHA-256.
  • The entropy and checksum are combined into a bit string.
  • The bit string is split into chunks of 11 bits, which are then mapped to the corresponding words from a predefined word list.

Valid Lengths

The length parameter must be one of the following values:

• 12 words (128 bits of entropy)
• 15 words (160 bits of entropy)
• 18 words (192 bits of entropy)
• 21 words (224 bits of entropy)
• 24 words (256 bits of entropy)

Error Handling

• Invalid length: The length parameter must be a multiple of 3 and between 12 and 24 (inclusive).
• Other potential errors: In case of any underlying failure (such as entropy generation or checksum calculation), the function returns a descriptive error message.

Dependencies

This crate depends on the following libraries:

• rand: For generating cryptographically secure random numbers.
• sha2: For performing SHA-256 hashing to calculate the checksum.

You can include these dependencies automatically by using the crate, but make sure you have them in your Cargo.toml if you're using them directly.