Software engineering has a strong distinction between abstract model and concrete implementation, yes? The properties of the interface of &#x2F;dev&#x2F;random indicate an attempt at being information-theoretically secure. I&#x27;ve <i>repeatedly</i> disclaimed that I&#x27;m well aware the implementation falls <i>well</i> short of such.<p>To me, XOR using &#x2F;dev&#x2F;random <i>should</i> be usable for a true OTP [0] whereas XOR using &#x2F;dev&#x2F;urandom has the security of the effective stream cipher.<p>[0] (malleability disclaimer, lest you think I&#x27;m arguing for the practicalities of &quot;OTP&quot; or something)