tailscale/util/rands/rands.go
Brad Fitzpatrick 7175f06e62 util/rands: add package with HexString func
We use it a number of places in different repos. Might as well make
one. Another use is coming.

Updates #cleanup

Change-Id: Ib7ce38de0db35af998171edee81ca875102349a4
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2023-09-05 09:17:21 -07:00

26 lines
534 B
Go

// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
// Package rands contains utility functions for randomness.
package rands
import (
crand "crypto/rand"
"encoding/hex"
)
// HexString returns a string of n cryptographically random lowercase
// hex characters.
//
// That is, HexString(3) returns something like "0fc", containing 12
// bits of randomness.
func HexString(n int) string {
nb := n / 2
if n%2 == 1 {
nb++
}
b := make([]byte, nb)
crand.Read(b)
return hex.EncodeToString(b)[:n]
}