go-rdrand

This library is to access CPU's RDRAND and RDSEED random number generator for some reason like you love Intel's (or AMD) black box instead of Linux's open source CSPRNG.

RDRAND and RDSEED

See Wikipedia.

TL;DR: It's an RNG(Random Number Generator) built in your processor.

RDRAND is broken on AMD processors prior to Zen.

RDSEED is supported after Broadwell (5th Gen and Xeon v4) and AMD Zen series. Using RDSEED with this library will be automatically fallback to RDRAND if not supported.

Run Check before use and fallback to other RNG solutions if it's not supported on your platform.

Usage

This library implements math/rand.Source64 interface, just use it with math/rand to get features like read to a byte slice.

package main

import (
	"fmt"
	"math/rand"
	"os"

	"github.com/fakeboboliu/go-rdrand"
)

func main() {
	// Check before use
	if err := rdrand.Check(); err != nil {
		if err == rdrand.ErrNoRdSeed {
			fmt.Println("Warning: RdSeed is not supported")
		} else {
			fmt.Println("RdRand cannot use:", err)
			os.Exit(1)
		}
	}

	// Init a rng with RDRAND
	rng := rand.New(rdrand.RdRand{})

	// use it as math/rand
	fmt.Println(rng.Intn(10))
	// or read bytes
	buf := make([]byte, 16)
	rng.Read(buf)
	fmt.Println(buf)

	// Or use RDSEED
	rng = rand.New(rdrand.RdSeed{})
}