From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from oss.cyber.gouv.fr (oss.cyber.gouv.fr [51.159.188.251]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 877423515D7; Sat, 26 Sep 2026 20:18:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=51.159.188.251 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790453887; cv=none; b=iHuCSHobAPXf8pYVbKpYcRv+zW1s43Ylhs8SO6U5pZ5mOadKyIOXIer9DwmD7mo37NfBiV2G1FhlmkjrisY3uFOCoRQekzNpmeW3Jr2T9Ie+Rlp8262Fk2STQnGYbMoaNUHUbVQr8MtI3O+iQoiF0H+Ar+sdRmCIB/YOMGD22aI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790453887; c=relaxed/simple; bh=cMPIx83xGeJHwh537+ZmkoMhqHj0AHKD0xEdNxlT8TY=; h=MIME-Version:Date:From:To:Cc:Subject:In-Reply-To:References: Message-ID:Content-Type; b=GSj6TU4KPj/G4eMvsVxQZheb831H/olu2j+3nCdB11hNbjf1v9GnDJsJyjIc0ltb9OXjgW31N6eWRwEqZavKZCR+V+nGUT59fGCW6XTyJnoQO+A4T2bB7OX+arlgEflxHmDOjNRpbW0fH+zW9vS0q4vn8+pQmwmWZCQvN1xKgQc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=oss.cyber.gouv.fr; spf=pass smtp.mailfrom=oss.cyber.gouv.fr; dkim=pass (2048-bit key) header.d=oss.cyber.gouv.fr header.i=@oss.cyber.gouv.fr header.b=EDhpoG7v; arc=none smtp.client-ip=51.159.188.251 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=oss.cyber.gouv.fr Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oss.cyber.gouv.fr Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=oss.cyber.gouv.fr header.i=@oss.cyber.gouv.fr header.b="EDhpoG7v" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=oss.cyber.gouv.fr; s=default; h=Content-Transfer-Encoding:Content-Type: Message-ID:References:In-Reply-To:Subject:Cc:To:From:Date:MIME-Version: Reply-To:Sender:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID; bh=GT/IbKfZEkygAriTq5cxZN3eZBPN9ViphrzqUeFcjVE=; b=EDhpoG7vaG40SjoanO27E9K9TL tssIHEebz1Lw/ZVFm5YJRbQOpx+JHmCjBoAOd4ZaCftRMmRwOv5kQXLcbYYlvZYI5AZyI3zXzgRFG LGOMzTF83RN+g5w3496Y9A9Ku3fPqJTfSu6LUA8PJQOlPP1FkJjvNbNciBcwHk5j8dRIouVc/CgNC 92vuTEQCNDvE9DNdBZZhQs/p03GpI6ADdjUrj2nhQZ7RBuDC2YunWcbk+T/RMw0UdU3f+fiLqDKhg n0LVMPuxwTlxwnXmJqhz2IcVvJVpTfDvBlVxmUSb1iGBTYgmABQz2TafW+zlCbMFIL+v7OHF5fzoP PindA5fA==; Received: from [::1] (port=44806 helo=pf-012.whm.fr-par.scw.cloud) by pf-012.whm.fr-par.scw.cloud with esmtpa (Exim 4.100.1) (envelope-from ) id 1xAYqT-00000000xu1-16cX; Sat, 26 Sep 2026 22:18:03 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Sat, 26 Sep 2026 22:18:01 +0200 From: =?UTF-8?Q?J=C3=A9r=C3=A9my_Jean?= To: Ignat Korchagin Cc: Lukas Wunner , Stefan Berger , Herbert Xu , "David S. Miller" , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] crypto: ecc - Handle exceptional points in Shamir multiplication In-Reply-To: References: <20260925132223.706291-2-Jeremy.Jean@oss.cyber.gouv.fr> User-Agent: Roundcube Webmail/1.6.19 Message-ID: <941ea3bacafb6c6dcc0edfe96a3f3fcd@oss.cyber.gouv.fr> X-Sender: jeremy.jean@oss.cyber.gouv.fr Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - pf-012.whm.fr-par.scw.cloud X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - oss.cyber.gouv.fr X-Get-Message-Sender-Via: pf-012.whm.fr-par.scw.cloud: authenticated_id: jeremy.jean@oss.cyber.gouv.fr X-Authenticated-Sender: pf-012.whm.fr-par.scw.cloud: jeremy.jean@oss.cyber.gouv.fr X-Source: X-Source-Args: X-Source-Dir: On 2026-09-26 16:17, Ignat Korchagin wrote: > On Fri, Sep 25, 2026 at 2:23 PM Jérémy Jean > wrote: >> >> Shamir multiplication mishandles equal points, opposite points and the >> point at infinity. This rejects valid ECDSA signatures and can accept >> invalid digest/signature tuples when the public key is G or -G. The > > Can you provide/construct test vectors for these? The ones that were > accepted, but should fail. Hello Ignat, Thanks for the answer. Good idea, I will add some in a v2. Jérémy