From owner-svn-src-stable@freebsd.org Mon Feb 27 14:02:13 2017 Return-Path: Delivered-To: svn-src-stable@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 474EFCEF829 for ; Mon, 27 Feb 2017 14:02:13 +0000 (UTC) (envelope-from ed@nuxi.nl) Received: from mail-yw0-x230.google.com (mail-yw0-x230.google.com [IPv6:2607:f8b0:4002:c05::230]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 10BB5808 for ; Mon, 27 Feb 2017 14:02:12 +0000 (UTC) (envelope-from ed@nuxi.nl) Received: by mail-yw0-x230.google.com with SMTP id l138so11862348ywc.0 for ; Mon, 27 Feb 2017 06:02:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nuxi-nl.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=fHqYQNBv5NxBvRsb+L+5F86AOB4sEIjeRmTQtO02egc=; b=LQyEQwXOLkVC6QAW9CssBW+jLj1YxY/JwNX3fCBRZ01C2yQXP0YOQ0QjpBglVPgMTh kkCAV993oEs1pnLdLQkLxshyewtyxWKPoRY/jPxL4r9IZiCyB+e11Rx4aPrP01lnSQrq DTueFRp11vzlYnOBamXF/RQwGqWvfY+5l7S8EGJJ2aEhUWGlbuP4vGZ4k9xa/8dN2V5E BqEj3vYpivqXEajEM+jk7BpWM5awv7FgXlz3SpkkRzg4/sR6TzSh82jLZEk2x5F6MOKl 5/GZXSPJydMSL/zEp6uc0qdaOxDQJmtD2q7hWvgFuItyCAWBH+9MPZbKeCM7e5yzQK9y fDKA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=fHqYQNBv5NxBvRsb+L+5F86AOB4sEIjeRmTQtO02egc=; b=eEoo8jQjmKn/jeIYuiQgwpoNVAPZqaDIizzhA3GaJvtu5LVjqlDhqzdZBxmQVROFxp kp+udLlr7AmLbTr5lqCGhQk7OVsj9trV7aOBTDlYywGWTXfpSaVYLh1d61+dBLYZwt84 LeWfprwsTtSJ95fD/+E9CfXmDznrTkbK0KON2m4Bzen8EmpY41Rfk6Az26yH+S2fcWwP D/sWTjoVJ68e7vQxRsxiGs8nFyr0SZ2SGhCAd+5SyvsdRFfo8DFkABXgEgzs4rXzehEs oFW1NCrC2zj1OD92v+pRzMAjl1De1jMldYQkWwPU0LtkjgxJzzE2bsD2+mTrOnD5kgxn WJsg== X-Gm-Message-State: AMke39k5BuB88nMJm7Y47W61PZl+aGhYIKo0fX90CVBxkBjVhc8EpJpXG4eq5s2NFetDK9vC1E8uM9hRPfD8RQ== X-Received: by 10.13.220.65 with SMTP id f62mr12184736ywe.6.1488204131878; Mon, 27 Feb 2017 06:02:11 -0800 (PST) MIME-Version: 1.0 Received: by 10.129.51.198 with HTTP; Mon, 27 Feb 2017 06:01:41 -0800 (PST) In-Reply-To: <201702271305.v1RD5HOi077424@repo.freebsd.org> References: <201702271305.v1RD5HOi077424@repo.freebsd.org> From: Ed Schouten Date: Mon, 27 Feb 2017 15:01:41 +0100 Message-ID: Subject: Re: svn commit: r314335 - stable/10/sys/crypto/sha2 To: Andriy Gapon Cc: src-committers , svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-10@freebsd.org Content-Type: text/plain; charset=UTF-8 X-BeenThere: svn-src-stable@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SVN commit messages for all the -stable branches of the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 27 Feb 2017 14:02:13 -0000 Hi Andriy, 2017-02-27 14:05 GMT+01:00 Andriy Gapon : > +/* Message schedule computation */ > +#define MSCH(W, ii, i) \ > + W[i + ii + 16] = s1(W[i + ii + 14]) + W[i + ii + 9] + s0(W[i + ii + 1]) + W[i + ii] [snip] > uint32_t W[64]; [snip] > + for (i = 0; i < 64; i += 16) { > + RNDr(S, W, 1, i); > + RNDr(S, W, 2, i); > + RNDr(S, W, 3, i); > + RNDr(S, W, 4, i); > + RNDr(S, W, 5, i); > + RNDr(S, W, 6, i); > + RNDr(S, W, 7, i); > + RNDr(S, W, 8, i); > + RNDr(S, W, 9, i); > + RNDr(S, W, 10, i); > + RNDr(S, W, 11, i); > + RNDr(S, W, 12, i); > + RNDr(S, W, 13, i); > + RNDr(S, W, 14, i); > + RNDr(S, W, 15, i); > + > + if (i == 48) > + break; > + MSCH(W, 0, i); > + MSCH(W, 1, i); > + MSCH(W, 2, i); > + MSCH(W, 3, i); > + MSCH(W, 4, i); > + MSCH(W, 5, i); > + MSCH(W, 6, i); > + MSCH(W, 7, i); > + MSCH(W, 8, i); > + MSCH(W, 9, i); > + MSCH(W, 10, i); > + MSCH(W, 11, i); > + MSCH(W, 12, i); > + MSCH(W, 13, i); > + MSCH(W, 14, i); > + MSCH(W, 15, i); > + } Something interesting that I noticed some time ago when comparing the various SHA-{256,512} implementations: there is no need to store the entire extended message in W. During every iteration of this loop, RNDr() and MSCH() never go more than 16 elements back. Say, if you were to modify MSCH() to something like this: > +#define MSCH(W, ii) \ > + W[ii] += s1(W[(ii + 14) % 16]) + W[(ii + 9) % 16] + s0(W[(ii + 1)) % 16]) Then it will compute the next chunk of the extended message in-place. RNDr() must then be adjusted to use W[i] instead of W[i + ii], of course. W then only needs to hold 16 elements instead of 64 or 80. -- Ed Schouten Nuxi, 's-Hertogenbosch, the Netherlands KvK-nr.: 62051717