25 lines
633 B
Go
25 lines
633 B
Go
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package crypto
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import (
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"errors"
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"fmt"
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// note: this is aliased so that it's more noticeable if someone
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// accidentally swaps it out for math/rand via running goimports
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cryptorand "crypto/rand"
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)
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// Bytes gets a slice of cryptographically random bytes of the given length and
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// enforces that we check for short reads to avoid entropy exhaustion.
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func Bytes(length int) ([]byte, error) {
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key := make([]byte, length)
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n, err := cryptorand.Read(key)
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if err != nil {
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return nil, fmt.Errorf("could not read from random source: %v", err)
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}
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if n < length {
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return nil, errors.New("entropy exhausted")
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}
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return key, nil
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}
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