From nobody Fri Feb 18 04:54:54 2022 X-Original-To: dev-commits-src-branches@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id DFBD119DEDA1; Fri, 18 Feb 2022 04:54:54 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4K0KB660KVz4vdQ; Fri, 18 Feb 2022 04:54:54 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1645160094; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=1NQLStKjyB6ozK63bg3NJ273v+6k7xVWDcul2z4wuE8=; b=uweC1vf6WgAXJB8LWcauNcAOBvYW/xT4q/08ySjlh3WCCdOg72DgjZs5Os/voDYMecYnju UTdRnJ+8WeRaPJebKzyYBShKeG8dtkqwa2dTGkcijflvcCHhD57evqKvD/VOY8MxFLQpLA kPYGGDFC16jW2Aj8DZMlCGoziZMIZrdMUEELI5WuveuQ5gbKEacdu6tv9kpECBJxkooQax z01ddfzb+fYZ+QqKL52OZ04UdTdEWJpY7ehLL6kGJXIiaYlQFllrQ+NRtaVYv3iSivt014 /2lUNiy0IUq1K292OXkzMEbZTL7FyWfV/TWdKCQuW1MeLyA+kK9P77xDDrwC4A== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id AD73617881; Fri, 18 Feb 2022 04:54:54 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 21I4ssJr070746; Fri, 18 Feb 2022 04:54:54 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 21I4ssvL070745; Fri, 18 Feb 2022 04:54:54 GMT (envelope-from git) Date: Fri, 18 Feb 2022 04:54:54 GMT Message-Id: <202202180454.21I4ssvL070745@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: "David E. O'Brien" Subject: git: dd9548db7a72 - stable/12 - kern: random: collect ~16x less from fast-entropy sources List-Id: Commits to the stable branches of the FreeBSD src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-branches List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-branches@freebsd.org X-BeenThere: dev-commits-src-branches@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: obrien X-Git-Repository: src X-Git-Refname: refs/heads/stable/12 X-Git-Reftype: branch X-Git-Commit: dd9548db7a72644b5ddd822a40162c3b5a1476d1 Auto-Submitted: auto-generated ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1645160094; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=1NQLStKjyB6ozK63bg3NJ273v+6k7xVWDcul2z4wuE8=; b=WpsjgoqWDm64skBRsuN9qcwIauSsKbPF90SzH7FuB9sVf33OfdLVkvt1tj/3E3qd4C2y+/ aldkDIJkFm6QWH01+i8/DC1PIro5TNMpgHRITnGRyhG+rKkUq0baPHT+DLtDXiJmxSfOZo NUDUFI0KsVIBmKmNbvwK2VepMlHtXXiBL2vRACCE7WlH8VJ4ouqT+MsKjApFA/9F+e1aTt OgqVs0Kb4EceQHRNsby9D+9YApWjG8KHx9PCNX4MhnFEhN6Y2Wqil59u1HITBUL4oP7bDS TkklUW38XbAtgRrVnD3RkYoCy4dynD+7wgqMxXdngczwwhRaShqRVdVRhrUTlw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1645160094; a=rsa-sha256; cv=none; b=OmvbnkOQYEBEmbvo2eLeRoOk15ZyWtldNr6ZAr8gMx7oy1Oq7in7j8jRJ0mFubdvZFSMWL H/uAWlPTPeCKV7P/LdZg9/GlpFxyg7UxA+F9+aeqyHu+Lb4RWO1FueGD/RO8e5pcALNXZ8 wOJqoyZsghZ1txX9DYkq5UMpbUE89jCvSRHACAI3NLPOh4arxyxyMuDFnW9ft52hgICL8h 4IdpSHSgLeWVRSAXcpICFq+okKoZq35O3qCDBxwNG6XaL66lyKQEfSA4D05ZKAIPDLT+Sz 17hvmKedC367fsUoVy1u83/gQLCN6co2+wXe+iKQaq8iOHAKJTUWNrtIWtR1YQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none X-ThisMailContainsUnwantedMimeParts: N The branch stable/12 has been updated by obrien: URL: https://cgit.FreeBSD.org/src/commit/?id=dd9548db7a72644b5ddd822a40162c3b5a1476d1 commit dd9548db7a72644b5ddd822a40162c3b5a1476d1 Author: Kyle Evans AuthorDate: 2021-09-20 05:46:21 +0000 Commit: David E. O'Brien CommitDate: 2022-02-18 04:09:47 +0000 kern: random: collect ~16x less from fast-entropy sources Previously, we were collecting at a base rate of: 64 bits x 32 pools x 10 Hz = 2.5 kB/s This change drops it to closer to 64-ish bits per pool per second, to work a little better with entropy providers in virtualized environments without compromising the security goals of Fortuna. (cherry picked from commit 5e79bba562bc303eed669dbd0d391b6c6a9c289b) (cherry picked from commit 06248c82158019f30a18494e7ce91ac5f9524452) --- sys/dev/random/random_harvestq.c | 27 ++++++++++++++++++++++++--- 1 file changed, 24 insertions(+), 3 deletions(-) diff --git a/sys/dev/random/random_harvestq.c b/sys/dev/random/random_harvestq.c index 035b5c028fb6..d98730d0054f 100644 --- a/sys/dev/random/random_harvestq.c +++ b/sys/dev/random/random_harvestq.c @@ -64,6 +64,13 @@ __FBSDID("$FreeBSD$"); #include #include +/* + * Note that random_sources_feed() will also use this to try and split up + * entropy into a subset of pools per iteration with the goal of feeding + * HARVESTSIZE into every pool at least once per second. + */ +#define RANDOM_KTHREAD_HZ 10 + static void random_kthread(void); static void random_sources_feed(void); @@ -192,7 +199,8 @@ random_kthread(void) } } /* XXX: FIX!! This is a *great* place to pass hardware/live entropy to random(9) */ - tsleep_sbt(&harvest_context.hc_kthread_proc, 0, "-", SBT_1S/10, 0, C_PREL(1)); + tsleep_sbt(&harvest_context.hc_kthread_proc, 0, "-", + SBT_1S/RANDOM_KTHREAD_HZ, 0, C_PREL(1)); } random_kthread_control = -1; wakeup(&harvest_context.hc_kthread_proc); @@ -213,7 +221,7 @@ random_sources_feed(void) { uint32_t entropy[HARVESTSIZE]; struct random_sources *rrs; - u_int i, n, local_read_rate; + u_int i, n, local_read_rate, npools; /* * Step over all of live entropy sources, and feed their output @@ -229,8 +237,21 @@ random_sources_feed(void) local_read_rate = MAX(local_read_rate, 1); /* But not exceeding RANDOM_KEYSIZE_WORDS */ local_read_rate = MIN(local_read_rate, RANDOM_KEYSIZE_WORDS); + + /* + * Evenly-ish distribute pool population across the second based on how + * frequently random_kthread iterates. + * + * For Fortuna, the math currently works out as such: + * 64 bits * 4 pools = 256 bits per iteration + * 256 bits * 10 Hz = 2560 bits per second, 320 B/s + * + */ + npools = howmany(p_random_alg_context->ra_poolcount * local_read_rate, + RANDOM_KTHREAD_HZ); + LIST_FOREACH(rrs, &source_list, rrs_entries) { - for (i = 0; i < p_random_alg_context->ra_poolcount*local_read_rate; i++) { + for (i = 0; i < npools; i++) { n = rrs->rrs_source->rs_read(entropy, sizeof(entropy)); KASSERT((n <= sizeof(entropy)), ("%s: rs_read returned too much data (%u > %zu)", __func__, n, sizeof(entropy))); /* It would appear that in some circumstances (e.g. virtualisation),