forked from sneak/util
clawbot
4937903190
RandomHexString returns the requested number of bytes from crypto/rand as lowercase hexadecimal, so callers reaching for a token do not end up using the predictable math/rand instead. Comes with a doc comment and table-driven tests. (closes #13) Model: opus-5
29 lines
843 B
Go
29 lines
843 B
Go
package util
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import (
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"crypto/rand"
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"encoding/hex"
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"errors"
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)
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// RandomHexString returns byteLength random bytes from the operating system's
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// random source, written as lowercase hexadecimal, so the returned string is
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// twice as long as byteLength. The bytes come from crypto/rand, which means the
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// result is fit for session tokens, temporary filenames and anything else a
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// stranger should not be able to guess.
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//
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// An error comes back only for a negative length or if the random source
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// itself fails, which does not happen on a working system.
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func RandomHexString(byteLength int) (string, error) {
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if byteLength < 0 {
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return "", errors.New("byte length cannot be negative")
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}
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buffer := make([]byte, byteLength)
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if _, err := rand.Read(buffer); err != nil {
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return "", err
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}
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return hex.EncodeToString(buffer), nil
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}
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