mirror of https://github.com/coder/coder.git
61 lines
1.3 KiB
Go
61 lines
1.3 KiB
Go
package cryptorand
|
|
|
|
import (
|
|
"crypto/rand"
|
|
"encoding/binary"
|
|
insecurerand "math/rand"
|
|
)
|
|
|
|
type cryptoSource struct {
|
|
err error
|
|
}
|
|
|
|
func (*cryptoSource) Seed(_ int64) {
|
|
// Intentionally disregard seed
|
|
}
|
|
|
|
func (c *cryptoSource) Int63() int64 {
|
|
var n int64
|
|
err := binary.Read(rand.Reader, binary.BigEndian, &n)
|
|
if err != nil {
|
|
c.err = err
|
|
}
|
|
// The sign bit must be cleared to ensure the final value is non-negative.
|
|
n &= 0x7fffffffffffffff
|
|
return n
|
|
}
|
|
|
|
func (c *cryptoSource) Uint64() uint64 {
|
|
var n uint64
|
|
err := binary.Read(rand.Reader, binary.BigEndian, &n)
|
|
if err != nil {
|
|
c.err = err
|
|
}
|
|
return n
|
|
}
|
|
|
|
// secureRand returns a cryptographically secure random number generator.
|
|
func secureRand() (*insecurerand.Rand, *cryptoSource) {
|
|
var cs cryptoSource
|
|
//nolint:gosec
|
|
return insecurerand.New(&cs), &cs
|
|
}
|
|
|
|
// Int64 returns a non-negative random 63-bit integer as a int64.
|
|
func Int63() (int64, error) {
|
|
rng, cs := secureRand()
|
|
return rng.Int63(), cs.err
|
|
}
|
|
|
|
// Intn returns a non-negative integer in [0,max) as an int.
|
|
func Intn(max int) (int, error) {
|
|
rng, cs := secureRand()
|
|
return rng.Intn(max), cs.err
|
|
}
|
|
|
|
// Float64 returns a random number in [0.0,1.0) as a float64.
|
|
func Float64() (float64, error) {
|
|
rng, cs := secureRand()
|
|
return rng.Float64(), cs.err
|
|
}
|