39 lines
825 B
Go
39 lines
825 B
Go
package net
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import (
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"crypto/rand"
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"crypto/sha256"
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"net"
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)
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func RandomMAC() (net.HardwareAddr, error) {
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mac := make([]byte, 6)
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if _, err := rand.Read(mac); err != nil {
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return nil, err
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}
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setUnicastAndLocal(mac)
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return net.HardwareAddr(mac), nil
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}
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func MACfromUUID(uuid []byte) net.HardwareAddr {
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hash := sha256.New()
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// We salt the input just as a precaution to avoid clashes with
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// other applications who might have had the bright idea of
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// generating MACs in the same way.
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hash.Write([]byte("9oBJ0Jmip-"))
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hash.Write(uuid)
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sum := hash.Sum(nil)
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setUnicastAndLocal(sum)
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return net.HardwareAddr(sum[:6])
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}
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// In the first byte of the MAC, the 'multicast' bit should be
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// clear and 'locally administered' bit should be set.
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func setUnicastAndLocal(mac []byte) {
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mac[0] = (mac[0] & 0xFE) | 0x02
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}
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