From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp2 ([2001:41d0:8:6d80::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms0.migadu.com with LMTPS id yMEeOaP/SmGdygAAgWs5BA (envelope-from ) for ; Wed, 22 Sep 2021 12:04:19 +0200 Received: from aspmx1.migadu.com ([2001:41d0:8:6d80::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp2 with LMTPS id /anQNKP/SmEtNQAAB5/wlQ (envelope-from ) for ; Wed, 22 Sep 2021 10:04:19 +0000 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by aspmx1.migadu.com (Postfix) with ESMTPS id 65CBFE7CB for ; Wed, 22 Sep 2021 12:04:15 +0200 (CEST) Received: from localhost ([::1]:35978 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mSz6r-0003ns-MG for larch@yhetil.org; Wed, 22 Sep 2021 06:04:13 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42012) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mSz6g-0003lw-MV for bug-guix@gnu.org; Wed, 22 Sep 2021 06:04:02 -0400 Received: from debbugs.gnu.org ([209.51.188.43]:37357) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1mSz6g-0005OH-CZ for bug-guix@gnu.org; Wed, 22 Sep 2021 06:04:02 -0400 Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1mSz6g-00075k-6Z for bug-guix@gnu.org; Wed, 22 Sep 2021 06:04:02 -0400 X-Loop: help-debbugs@gnu.org Subject: bug#44187: Channel clones lack SWH fallback Resent-From: Ludovic =?UTF-8?Q?Court=C3=A8s?= Original-Sender: "Debbugs-submit" Resent-CC: bug-guix@gnu.org Resent-Date: Wed, 22 Sep 2021 10:04:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 44187 X-GNU-PR-Package: guix X-GNU-PR-Keywords: To: zimoun Received: via spool by 44187-done@debbugs.gnu.org id=D44187.163230502527234 (code D ref 44187); Wed, 22 Sep 2021 10:04:02 +0000 Received: (at 44187-done) by debbugs.gnu.org; 22 Sep 2021 10:03:45 +0000 Received: from localhost ([127.0.0.1]:48903 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1mSz6P-00075C-4z for submit@debbugs.gnu.org; Wed, 22 Sep 2021 06:03:45 -0400 Received: from eggs.gnu.org ([209.51.188.92]:52982) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1mSz6J-00074t-U3 for 44187-done@debbugs.gnu.org; Wed, 22 Sep 2021 06:03:43 -0400 Received: from fencepost.gnu.org ([2001:470:142:3::e]:58322) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mSz6E-0004ys-NE; Wed, 22 Sep 2021 06:03:34 -0400 Received: from [2a01:e0a:1d:7270:af76:b9b:ca24:c465] (port=35964 helo=ribbon) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mSz6E-0004U5-Dq; Wed, 22 Sep 2021 06:03:34 -0400 From: Ludovic =?UTF-8?Q?Court=C3=A8s?= References: <87pn0dk61v.fsf@gnu.org> <20210910143415.14783-1-ludo@gnu.org> <86o88r1vfe.fsf@gmail.com> <87pmt5si8b.fsf@gnu.org> X-URL: http://www.fdn.fr/~lcourtes/ X-Revolutionary-Date: 1 =?UTF-8?Q?Vend=C3=A9miaire?= an 230 de la =?UTF-8?Q?R=C3=A9volution?= X-PGP-Key-ID: 0x090B11993D9AEBB5 X-PGP-Key: http://www.fdn.fr/~lcourtes/ludovic.asc X-PGP-Fingerprint: 3CE4 6455 8A84 FDC6 9DB4 0CFB 090B 1199 3D9A EBB5 X-OS: x86_64-pc-linux-gnu Date: Wed, 22 Sep 2021 12:03:32 +0200 In-Reply-To: (zimoun's message of "Mon, 20 Sep 2021 11:27:32 +0200") Message-ID: <87fstxhqq3.fsf@gnu.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-guix@gnu.org List-Id: Bug reports for GNU Guix List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: 44187-done@debbugs.gnu.org Errors-To: bug-guix-bounces+larch=yhetil.org@gnu.org Sender: "bug-Guix" X-Migadu-Flow: FLOW_IN ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1632305055; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding:resent-cc: resent-from:resent-sender:resent-message-id:in-reply-to:in-reply-to: references:references:list-id:list-help:list-unsubscribe: list-subscribe:list-post; bh=eFxl/uOIkcQqVhWOPRjyrsmHTcM/h3c32TU5Dgs2hdE=; b=bYeIjCiqZJlax/F3L8dC0kQiHBcPT69Aem8XDrVz4TKs0Bv0qaHbhVFjwGzcxST1hnKvg0 MKOM+F6+J0dj6Uc8ZaR4kXRRkDpnje5uyCtYOZX8ex7YgxROq5s8F82jEiQbToftfvscv3 IP7vhGZkuhF17P63nE/FIxsltI4YB5g3cd9lD06agWxMPIqSJ8n689GiNaiecCrzon8S32 ocaQY0vx8+qhBo1nlQSSQHNLofH3quoqbQTNFWro2wth+cSf4GrW+VXjlBEOfxdHRo8Zl+ ifDjPBhjb2v+yxTbd3FWkM9Oa3u3i0V7KlPU7ixGz1ItTbmcn0ML+stFS3diRQ== ARC-Seal: i=1; s=key1; d=yhetil.org; t=1632305055; a=rsa-sha256; cv=none; b=J0t93wmO7rFS15bDF6kxXXSkSY0hFaNG+EZWVFD9Rgx+Zl3TgAIKgcAb4qeY8vXDll+D9E hK3rI55hg5BAQg9DLUXnlwxji/ZRF3VGCztpvnhzpjA/EByCp8o66IKO4lluHmgLncObn9 x2Z109HRmPV8LksaY1qRk9DsGHWgUIuz/LN3ptEC2tI5Cl3JBAZfAZTbO0T7vFNz0rBuwk 4TO3ec2u0Qiy9mxMg1eP6I5pQlMa7IA9gTYNCDGLskX5mbz8SxWmEQexMHVEltv2o3hP8u mQfDx03kJSESI7hFqYwXkm0rXxIwV4NR8lw2bim20tmKgZFSuWQib+m73x/jfw== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=none; spf=pass (aspmx1.migadu.com: domain of bug-guix-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=bug-guix-bounces@gnu.org X-Migadu-Spam-Score: -2.89 Authentication-Results: aspmx1.migadu.com; dkim=none; dmarc=pass (policy=none) header.from=gnu.org; spf=pass (aspmx1.migadu.com: domain of bug-guix-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=bug-guix-bounces@gnu.org X-Migadu-Queue-Id: 65CBFE7CB X-Spam-Score: -2.89 X-Migadu-Scanner: scn0.migadu.com X-TUID: g+0IxFjgfifa Hi, zimoun skribis: > On Sat, 18 Sept 2021 at 23:10, Ludovic Court=C3=A8s wrote: [...] >> > How a chosen-prefix attack could work here? I understand why the seco= nd >> > preimage attack is an issue. But I miss how the SHA-1 chosen-prefix a= ttack >> > could be exploited here to compromise the user, because this hash is p= rovided >> > by this very same user. >> >> I think you=E2=80=99re right, it=E2=80=99s rather second-preimage attack= s that would be >> a serious problem. My point is: as time passes, assuming that a SHA1 >> resolves to a single revision on SWH is becoming more and more >> questionable. > > Well, SHA-1 is 2^160 (~10^48.2) and compared to 10^50 which is the > estimated number of atoms in Earth. Speaking about > content-addressability, SHA-1 seems fine. However, for security, yeah > time flies. :-) True! >> >> swh: Support downloads of bare Git repositories. >> >> git: 'update-cached-checkout' can fall back to SWH when cloning. >> >> git: 'reference-available?' recognizes 'tag-or-commit'. >> >> I=E2=80=99ve pushed this after adding the warning as you suggested: >> >> dce2cf311b * git: 'reference-available?' recognizes 'tag-or-commit'. >> 05f44c2d85 * git: 'update-cached-checkout' can fall back to SWH when c= loning. >> 6ec81c31c0 * swh: Support downloads of bare Git repositories. > > Cool! I would deserve a --news entry. ;-) That=E2=80=99s a good idea, I=E2=80=99ve added one. Thanks, Ludo=E2=80=99.