Lunatik

• Index

Contents

• Class RNG
• rng

Modules

• completion
• crypto.aead
• crypto.comp
• crypto.rng
• crypto.shash
• crypto.skcipher
• data
• device
• fib
• fifo
• linux
• lunatik
• lunatik.runner
• mailbox
• net
• netfilter
• notifier
• probe
• rcu
• socket
• socket.inet
• syscall
• syscall.table
• thread
• xdp
• xtable

Topics

• README

Module crypto.rng

Low-level Lua interface to the Linux Kernel Crypto API for synchronous Random Number Generators (RNG).

This module provides a new function to create RNG objects, which can then be used for generating random bytes.

Class RNG

rng

Class RNG

rng:generate (num_bytes[, seed])

Generates a specified number of random bytes, with optional seed.

Parameters:

• num_bytes integer The number of random bytes to generate.
• seed string Optional seed material to mix into the RNG. If nil or omitted, no explicit seed is used. (optional)

Returns:

string A binary string containing the generated random bytes.

Raises:

Error on failure (e.g., allocation error, crypto API error).

rng:getbytes (num_bytes)

Generates a specified number of random bytes. This function does not take an explicit seed as an argument.

Parameters:

• num_bytes integer The number of random bytes to generate.

Returns:

string A binary string containing the generated random bytes.

Raises:

Error on failure (e.g., allocation error, crypto API error).

rng:info ()

Retrieves information about the RNG algorithm.

Returns:

table A table containing algorithm information, e.g., { driver_name = "...", seedsize = num }.

rng:reset ([seed])

Resets the RNG. This can be used to re-initialize the RNG, optionally with new seed material.

Parameters:

• seed string Optional seed material to mix into the RNG. If nil or omitted, the RNG will reseed from its default sources. (optional)

Raises:

Error on failure (e.g., crypto API error).

rng

new (algname)

Creates a new RNG object. This is the constructor function for the crypto_rng module.

Parameters:

• algname string The name of the RNG algorithm (e.g., "stdrng", "drbgnoprctr_aes256"). Defaults to "stdrng" if nil or omitted.

Returns:

crypto_rng The new RNG object.

Raises:

Error if the TFM object cannot be allocated/initialized.

Usage:

local rng_mod = require("crypto.rng")
local rng = rng_mod.new()  -- Uses default "stdrng"
local random_bytes = rng:generate(32)  -- Get 32 random bytes