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