From nobody Fri Oct 30 12:26:35 2020 Return-Path: X-Original-To: lwip@ietfa.amsl.com Delivered-To: lwip@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id B08CF3A116E; Fri, 30 Oct 2020 12:26:33 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -2.347 X-Spam-Level: X-Spam-Status: No, score=-2.347 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.247, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=iki.fi Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id CJjAeJ5j7L7Y; Fri, 30 Oct 2020 12:26:31 -0700 (PDT) Received: from meesny.iki.fi (meesny.iki.fi [IPv6:2001:67c:2b0:1c1::201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 56FE43A116D; Fri, 30 Oct 2020 12:26:30 -0700 (PDT) Received: from fireball.acr.fi (fireball.kivinen.iki.fi [IPv6:2001:1bc8:100d::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: kivinen) by meesny.iki.fi (Postfix) with ESMTPSA id D759820AD3; Fri, 30 Oct 2020 21:26:26 +0200 (EET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=iki.fi; s=meesny; t=1604085986; h=from:from: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: in-reply-to:in-reply-to:references:references; bh=p4bcr5mDGgC4+UN5bjZjOQN6rANuAHsfk2XVtSwwbM8=; b=UzabmDrPxvLDe3iJCgJWOQcdRXFukajUwweHBtSCIOFfupy9JHhl8Wy1r736b9E0pCnTIz ng6BT6STViveGKC/XxJj4YksnDY5pNgoTdninipcNfVgELXeoCEbH9+ADwY9BJWvaDypYj G+Y19o8qj6plgmjxN4i/0wZL2AZhuvs= Received: by fireball.acr.fi (Postfix, from userid 15204) id 9D4F625C131F; Fri, 30 Oct 2020 21:26:26 +0200 (EET) MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Message-ID: <24476.26850.591422.567867@fireball.acr.fi> Date: Fri, 30 Oct 2020 21:26:26 +0200 From: Tero Kivinen To: Daniel Migault Cc: Valery Smyslov , IPsecME WG , lwip@ietf.org, Tobias Guggemos In-Reply-To: References: <060501d5a9da$b8552490$28ff6db0$@gmail.com> X-Mailer: VM 8.2.0b under 26.3 (x86_64--netbsd) X-Edit-Time: 5 min X-Total-Time: 7 min ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=iki.fi; s=meesny; t=1604085986; h=from:from: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: in-reply-to:in-reply-to:references:references; bh=p4bcr5mDGgC4+UN5bjZjOQN6rANuAHsfk2XVtSwwbM8=; b=Tgf1L8hjw0ETK2sluEXzdZUwk8cYA9mRnDi+ppyWSEsjzoZNbZG5P4ttVBuW6VEnAVzmPB AM1T/b0lAqbpyrfdFE0acpEEpkp6bcL4gD1mIDkic0UA/7Qq7xdfZQelPdtJRDOSV9Z8vT ISdlvsR3sIvitVuEWP9XNd4RDio2CLU= ARC-Authentication-Results: i=1; ORIGINATING; auth=pass smtp.auth=kivinen smtp.mailfrom=kivinen@iki.fi ARC-Seal: i=1; s=meesny; d=iki.fi; t=1604085986; a=rsa-sha256; cv=none; b=lMOadup9TRTfm4HQ0a7u/eCHxCRYR6tYIqY+wXRNfMajuFoDiz29Ou/ZH5S7qqnoNn1rPM 0uDsowJbConLIoVXdlKYnqnUvf7acPHPcPG43i2xgXYp4DHTi35rjT3/rPr/0JD+KkwKD/ 745gU69S1DcFr0+Cd1tkKUYTeeWArSU= Archived-At: Subject: Re: [Lwip] Review of draft-ietf-lwig-minimal-esp-00 X-BeenThere: lwip@ietf.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Lightweight IP stack. Official mailing list for IETF LWIG Working Group." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Oct 2020 19:26:34 -0000 Daniel Migault writes: > =A0 =A0value SN needs to be considered instead.=A0 Note that the limi= t of > =A0 =A0messages being sent is primary determined by the security asso= ciated > =A0 =A0to the key rather than the SN.=A0 The security of the key used= to > =A0 =A0encrypt decreases with the each message being sent and a node = MUST > =A0 =A0ensure the limit is not reached - even though the SN would per= mit it. > =A0 =A0In a constrained environment, it is likely that the implementa= tion of a > =A0 =A0rekey mechanism is preferred over the use of ESN. No. The security of the key does not decrease, but the ability for the attacker to attack the key might incrase, and the value of attacking that one key also increases when more data is encrypted with it. Also with short block length algorithms there were stricter limits of data that can be encrypted with one key. --=20 kivinen@iki.fi