forked from mirrors/gotosocial
31 lines
723 B
Go
31 lines
723 B
Go
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// Copyright 2016 The Mellium Contributors.
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// Use of this source code is governed by the BSD 2-clause license that can be
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// found in the LICENSE file.
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package sasl
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import (
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"encoding/base64"
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"io"
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)
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// Generates a nonce with n random bytes base64 encoded to ensure that it meets
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// the criteria for inclusion in a SCRAM message.
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func nonce(n int, r io.Reader) []byte {
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if n < 1 {
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panic("Cannot generate zero or negative length nonce")
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}
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b := make([]byte, n)
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n2, err := r.Read(b)
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switch {
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case err != nil:
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panic(err)
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case n2 != n:
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panic("Could not read enough randomness to generate nonce")
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}
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val := make([]byte, base64.RawStdEncoding.EncodedLen(n))
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base64.RawStdEncoding.Encode(val, b)
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return val
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}
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