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Ts'o" To: Sandy Harris Cc: Linux Crypto Mailing List , Linux Kernel Developers List , labbott@redhat.com Subject: Re: [PATCH] random: addu a config option to trust the CPU's hwrng Message-ID: <20180719142148.GH30706@thunk.org> Mail-Followup-To: "Theodore Y. Ts'o" , Sandy Harris , Linux Crypto Mailing List , Linux Kernel Developers List , labbott@redhat.com References: <20180718014344.1309-1-tytso@mit.edu> <20180718015154.GE3489@thunk.org> <20180718173621.GC30706@thunk.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.0 (2018-05-17) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on imap.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 18, 2018 at 04:22:35PM -0400, Sandy Harris wrote: > > Yes & one of those can also solve any difficulty with random(4) at > startup. Another alternative, perhaps easier on some systems, is > Denker's Turbid trng: > https://www.av8n.com/turbid/paper/turbid.htm In the link above I saw breadboards with resistors plugged in, alligator clips to TRG plugs, shield boxes with aluminum foil, and doing calibrations using voltmeters. While that induced a pleasant flashback to my junior high days when I experimented with electronics, I'm not entirely sure most sysadmins would call that "easy". :-) - Ted