38 lines
575 B
Go
38 lines
575 B
Go
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// NOT true random number generation on RP2040 but good enough for quick demos.
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// Do not use in important production systems.
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// Seriously, don't.
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package main
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import (
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"machine"
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"crypto/rand"
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)
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func init() {
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rand.Reader = &reader{}
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}
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type reader struct{}
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func (r *reader) Read(b []byte) (n int, err error) {
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if len(b) == 0 {
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return
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}
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var randomByte uint32
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for i := range b {
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if i%4 == 0 {
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randomByte, err = machine.GetRNG()
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if err != nil {
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return n, err
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}
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} else {
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randomByte >>= 8
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}
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b[i] = byte(randomByte)
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}
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return len(b), nil
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}
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