| // Copyright 2016 The Go Authors. All rights reserved. | |
| // Use of this source code is governed by a BSD-style | |
| // license that can be found in the LICENSE file. | |
| package sysrand | |
| import "internal/syscall/unix" | |
| func read(b []byte) error { | |
| for len(b) > 0 { | |
| size := len(b) | |
| // "Returns independent uniformly distributed bytes at random each time, | |
| // as many as requested up to 256, derived from the system entropy pool; | |
| // see rnd(4)." -- man sysctl(7) | |
| if size > 256 { | |
| size = 256 | |
| } | |
| if err := unix.Arandom(b[:size]); err != nil { | |
| return err | |
| } | |
| b = b[size:] | |
| } | |
| return nil | |
| } | |