slowrand

README

slowrand

Slow deterministic random generator.

Rationale

Some problems might require random deterministic generator, but this might be problematic due to brute-force attacks. This (deterministic) random generator addresses this problem by increasing it's work time.

Note

Inspired by cornfeedhobo/ssh-keydgen

Features

• Slow
• Deterministic
• Random
• Dependency-free

Install

Go version 1.15+

go get github.com/cristalhq/slowrand

Example

seed := []byte("some-secure-seed")
rounds := 3
time := uint32(5)
memory := uint32(7)
threads := uint8(11)

r, err := slowrand.New(seed, rounds, time, memory, threads)
if err != nil {
    t.Fatal(err)
}

var buf [42]byte
n, err := r.Read(buf[:])
if n != 42 {
    panic("not 42")
}
_ = err // is always nil

Documentation

See these docs.

License

MIT License.

Documentation

Index

• type Reader
  • func New(seed []byte, rounds int, time, memory uint32, threads uint8) (*Reader, error)
  • func (r *Reader) Len() int
  • func (r *Reader) Read(b []byte) (int, error)

Types

type Reader

type Reader struct {
	// contains filtered or unexported fields
}

Reader represents a deterministic rand source from seed. Slowness is a feature to prevent brute-force attack.

func New

func New(seed []byte, rounds int, time, memory uint32, threads uint8) (*Reader, error)

New instance of slow reader. Seed as a start of the pseudorandom sequence. Rounds, time, memory and threads are params to the underlying PBKDF2 & Argon2 algorithms.

func (*Reader) Len

func (r *Reader) Len() int

Len returns number of read bytes.

func (*Reader) Read

func (r *Reader) Read(b []byte) (int, error)